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-rw-r--r--fs/btrfs/volumes.c8497
1 files changed, 8497 insertions, 0 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
new file mode 100644
index 000000000..6fc2d9927
--- /dev/null
+++ b/fs/btrfs/volumes.c
@@ -0,0 +1,8497 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2007 Oracle. All rights reserved.
+ */
+
+#include <linux/sched.h>
+#include <linux/sched/mm.h>
+#include <linux/bio.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include <linux/ratelimit.h>
+#include <linux/kthread.h>
+#include <linux/raid/pq.h>
+#include <linux/semaphore.h>
+#include <linux/uuid.h>
+#include <linux/list_sort.h>
+#include <linux/namei.h>
+#include "misc.h"
+#include "ctree.h"
+#include "extent_map.h"
+#include "disk-io.h"
+#include "transaction.h"
+#include "print-tree.h"
+#include "volumes.h"
+#include "raid56.h"
+#include "async-thread.h"
+#include "check-integrity.h"
+#include "rcu-string.h"
+#include "dev-replace.h"
+#include "sysfs.h"
+#include "tree-checker.h"
+#include "space-info.h"
+#include "block-group.h"
+#include "discard.h"
+#include "zoned.h"
+
+static struct bio_set btrfs_bioset;
+
+#define BTRFS_BLOCK_GROUP_STRIPE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \
+ BTRFS_BLOCK_GROUP_RAID10 | \
+ BTRFS_BLOCK_GROUP_RAID56_MASK)
+
+const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
+ [BTRFS_RAID_RAID10] = {
+ .sub_stripes = 2,
+ .dev_stripes = 1,
+ .devs_max = 0, /* 0 == as many as possible */
+ .devs_min = 2,
+ .tolerated_failures = 1,
+ .devs_increment = 2,
+ .ncopies = 2,
+ .nparity = 0,
+ .raid_name = "raid10",
+ .bg_flag = BTRFS_BLOCK_GROUP_RAID10,
+ .mindev_error = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET,
+ },
+ [BTRFS_RAID_RAID1] = {
+ .sub_stripes = 1,
+ .dev_stripes = 1,
+ .devs_max = 2,
+ .devs_min = 2,
+ .tolerated_failures = 1,
+ .devs_increment = 2,
+ .ncopies = 2,
+ .nparity = 0,
+ .raid_name = "raid1",
+ .bg_flag = BTRFS_BLOCK_GROUP_RAID1,
+ .mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET,
+ },
+ [BTRFS_RAID_RAID1C3] = {
+ .sub_stripes = 1,
+ .dev_stripes = 1,
+ .devs_max = 3,
+ .devs_min = 3,
+ .tolerated_failures = 2,
+ .devs_increment = 3,
+ .ncopies = 3,
+ .nparity = 0,
+ .raid_name = "raid1c3",
+ .bg_flag = BTRFS_BLOCK_GROUP_RAID1C3,
+ .mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET,
+ },
+ [BTRFS_RAID_RAID1C4] = {
+ .sub_stripes = 1,
+ .dev_stripes = 1,
+ .devs_max = 4,
+ .devs_min = 4,
+ .tolerated_failures = 3,
+ .devs_increment = 4,
+ .ncopies = 4,
+ .nparity = 0,
+ .raid_name = "raid1c4",
+ .bg_flag = BTRFS_BLOCK_GROUP_RAID1C4,
+ .mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET,
+ },
+ [BTRFS_RAID_DUP] = {
+ .sub_stripes = 1,
+ .dev_stripes = 2,
+ .devs_max = 1,
+ .devs_min = 1,
+ .tolerated_failures = 0,
+ .devs_increment = 1,
+ .ncopies = 2,
+ .nparity = 0,
+ .raid_name = "dup",
+ .bg_flag = BTRFS_BLOCK_GROUP_DUP,
+ .mindev_error = 0,
+ },
+ [BTRFS_RAID_RAID0] = {
+ .sub_stripes = 1,
+ .dev_stripes = 1,
+ .devs_max = 0,
+ .devs_min = 1,
+ .tolerated_failures = 0,
+ .devs_increment = 1,
+ .ncopies = 1,
+ .nparity = 0,
+ .raid_name = "raid0",
+ .bg_flag = BTRFS_BLOCK_GROUP_RAID0,
+ .mindev_error = 0,
+ },
+ [BTRFS_RAID_SINGLE] = {
+ .sub_stripes = 1,
+ .dev_stripes = 1,
+ .devs_max = 1,
+ .devs_min = 1,
+ .tolerated_failures = 0,
+ .devs_increment = 1,
+ .ncopies = 1,
+ .nparity = 0,
+ .raid_name = "single",
+ .bg_flag = 0,
+ .mindev_error = 0,
+ },
+ [BTRFS_RAID_RAID5] = {
+ .sub_stripes = 1,
+ .dev_stripes = 1,
+ .devs_max = 0,
+ .devs_min = 2,
+ .tolerated_failures = 1,
+ .devs_increment = 1,
+ .ncopies = 1,
+ .nparity = 1,
+ .raid_name = "raid5",
+ .bg_flag = BTRFS_BLOCK_GROUP_RAID5,
+ .mindev_error = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET,
+ },
+ [BTRFS_RAID_RAID6] = {
+ .sub_stripes = 1,
+ .dev_stripes = 1,
+ .devs_max = 0,
+ .devs_min = 3,
+ .tolerated_failures = 2,
+ .devs_increment = 1,
+ .ncopies = 1,
+ .nparity = 2,
+ .raid_name = "raid6",
+ .bg_flag = BTRFS_BLOCK_GROUP_RAID6,
+ .mindev_error = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET,
+ },
+};
+
+/*
+ * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
+ * can be used as index to access btrfs_raid_array[].
+ */
+enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags)
+{
+ const u64 profile = (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK);
+
+ if (!profile)
+ return BTRFS_RAID_SINGLE;
+
+ return BTRFS_BG_FLAG_TO_INDEX(profile);
+}
+
+const char *btrfs_bg_type_to_raid_name(u64 flags)
+{
+ const int index = btrfs_bg_flags_to_raid_index(flags);
+
+ if (index >= BTRFS_NR_RAID_TYPES)
+ return NULL;
+
+ return btrfs_raid_array[index].raid_name;
+}
+
+int btrfs_nr_parity_stripes(u64 type)
+{
+ enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(type);
+
+ return btrfs_raid_array[index].nparity;
+}
+
+/*
+ * Fill @buf with textual description of @bg_flags, no more than @size_buf
+ * bytes including terminating null byte.
+ */
+void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf)
+{
+ int i;
+ int ret;
+ char *bp = buf;
+ u64 flags = bg_flags;
+ u32 size_bp = size_buf;
+
+ if (!flags) {
+ strcpy(bp, "NONE");
+ return;
+ }
+
+#define DESCRIBE_FLAG(flag, desc) \
+ do { \
+ if (flags & (flag)) { \
+ ret = snprintf(bp, size_bp, "%s|", (desc)); \
+ if (ret < 0 || ret >= size_bp) \
+ goto out_overflow; \
+ size_bp -= ret; \
+ bp += ret; \
+ flags &= ~(flag); \
+ } \
+ } while (0)
+
+ DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data");
+ DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system");
+ DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata");
+
+ DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single");
+ for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
+ DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag,
+ btrfs_raid_array[i].raid_name);
+#undef DESCRIBE_FLAG
+
+ if (flags) {
+ ret = snprintf(bp, size_bp, "0x%llx|", flags);
+ size_bp -= ret;
+ }
+
+ if (size_bp < size_buf)
+ buf[size_buf - size_bp - 1] = '\0'; /* remove last | */
+
+ /*
+ * The text is trimmed, it's up to the caller to provide sufficiently
+ * large buffer
+ */
+out_overflow:;
+}
+
+static int init_first_rw_device(struct btrfs_trans_handle *trans);
+static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info);
+static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
+static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
+ enum btrfs_map_op op, u64 logical, u64 *length,
+ struct btrfs_io_context **bioc_ret,
+ struct btrfs_io_stripe *smap,
+ int *mirror_num_ret, int need_raid_map);
+
+/*
+ * Device locking
+ * ==============
+ *
+ * There are several mutexes that protect manipulation of devices and low-level
+ * structures like chunks but not block groups, extents or files
+ *
+ * uuid_mutex (global lock)
+ * ------------------------
+ * protects the fs_uuids list that tracks all per-fs fs_devices, resulting from
+ * the SCAN_DEV ioctl registration or from mount either implicitly (the first
+ * device) or requested by the device= mount option
+ *
+ * the mutex can be very coarse and can cover long-running operations
+ *
+ * protects: updates to fs_devices counters like missing devices, rw devices,
+ * seeding, structure cloning, opening/closing devices at mount/umount time
+ *
+ * global::fs_devs - add, remove, updates to the global list
+ *
+ * does not protect: manipulation of the fs_devices::devices list in general
+ * but in mount context it could be used to exclude list modifications by eg.
+ * scan ioctl
+ *
+ * btrfs_device::name - renames (write side), read is RCU
+ *
+ * fs_devices::device_list_mutex (per-fs, with RCU)
+ * ------------------------------------------------
+ * protects updates to fs_devices::devices, ie. adding and deleting
+ *
+ * simple list traversal with read-only actions can be done with RCU protection
+ *
+ * may be used to exclude some operations from running concurrently without any
+ * modifications to the list (see write_all_supers)
+ *
+ * Is not required at mount and close times, because our device list is
+ * protected by the uuid_mutex at that point.
+ *
+ * balance_mutex
+ * -------------
+ * protects balance structures (status, state) and context accessed from
+ * several places (internally, ioctl)
+ *
+ * chunk_mutex
+ * -----------
+ * protects chunks, adding or removing during allocation, trim or when a new
+ * device is added/removed. Additionally it also protects post_commit_list of
+ * individual devices, since they can be added to the transaction's
+ * post_commit_list only with chunk_mutex held.
+ *
+ * cleaner_mutex
+ * -------------
+ * a big lock that is held by the cleaner thread and prevents running subvolume
+ * cleaning together with relocation or delayed iputs
+ *
+ *
+ * Lock nesting
+ * ============
+ *
+ * uuid_mutex
+ * device_list_mutex
+ * chunk_mutex
+ * balance_mutex
+ *
+ *
+ * Exclusive operations
+ * ====================
+ *
+ * Maintains the exclusivity of the following operations that apply to the
+ * whole filesystem and cannot run in parallel.
+ *
+ * - Balance (*)
+ * - Device add
+ * - Device remove
+ * - Device replace (*)
+ * - Resize
+ *
+ * The device operations (as above) can be in one of the following states:
+ *
+ * - Running state
+ * - Paused state
+ * - Completed state
+ *
+ * Only device operations marked with (*) can go into the Paused state for the
+ * following reasons:
+ *
+ * - ioctl (only Balance can be Paused through ioctl)
+ * - filesystem remounted as read-only
+ * - filesystem unmounted and mounted as read-only
+ * - system power-cycle and filesystem mounted as read-only
+ * - filesystem or device errors leading to forced read-only
+ *
+ * The status of exclusive operation is set and cleared atomically.
+ * During the course of Paused state, fs_info::exclusive_operation remains set.
+ * A device operation in Paused or Running state can be canceled or resumed
+ * either by ioctl (Balance only) or when remounted as read-write.
+ * The exclusive status is cleared when the device operation is canceled or
+ * completed.
+ */
+
+DEFINE_MUTEX(uuid_mutex);
+static LIST_HEAD(fs_uuids);
+struct list_head * __attribute_const__ btrfs_get_fs_uuids(void)
+{
+ return &fs_uuids;
+}
+
+/*
+ * alloc_fs_devices - allocate struct btrfs_fs_devices
+ * @fsid: if not NULL, copy the UUID to fs_devices::fsid
+ * @metadata_fsid: if not NULL, copy the UUID to fs_devices::metadata_fsid
+ *
+ * Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR().
+ * The returned struct is not linked onto any lists and can be destroyed with
+ * kfree() right away.
+ */
+static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid,
+ const u8 *metadata_fsid)
+{
+ struct btrfs_fs_devices *fs_devs;
+
+ fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL);
+ if (!fs_devs)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&fs_devs->device_list_mutex);
+
+ INIT_LIST_HEAD(&fs_devs->devices);
+ INIT_LIST_HEAD(&fs_devs->alloc_list);
+ INIT_LIST_HEAD(&fs_devs->fs_list);
+ INIT_LIST_HEAD(&fs_devs->seed_list);
+ if (fsid)
+ memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
+
+ if (metadata_fsid)
+ memcpy(fs_devs->metadata_uuid, metadata_fsid, BTRFS_FSID_SIZE);
+ else if (fsid)
+ memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE);
+
+ return fs_devs;
+}
+
+void btrfs_free_device(struct btrfs_device *device)
+{
+ WARN_ON(!list_empty(&device->post_commit_list));
+ rcu_string_free(device->name);
+ extent_io_tree_release(&device->alloc_state);
+ btrfs_destroy_dev_zone_info(device);
+ kfree(device);
+}
+
+static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
+{
+ struct btrfs_device *device;
+
+ WARN_ON(fs_devices->opened);
+ while (!list_empty(&fs_devices->devices)) {
+ device = list_entry(fs_devices->devices.next,
+ struct btrfs_device, dev_list);
+ list_del(&device->dev_list);
+ btrfs_free_device(device);
+ }
+ kfree(fs_devices);
+}
+
+void __exit btrfs_cleanup_fs_uuids(void)
+{
+ struct btrfs_fs_devices *fs_devices;
+
+ while (!list_empty(&fs_uuids)) {
+ fs_devices = list_entry(fs_uuids.next,
+ struct btrfs_fs_devices, fs_list);
+ list_del(&fs_devices->fs_list);
+ free_fs_devices(fs_devices);
+ }
+}
+
+static noinline struct btrfs_fs_devices *find_fsid(
+ const u8 *fsid, const u8 *metadata_fsid)
+{
+ struct btrfs_fs_devices *fs_devices;
+
+ ASSERT(fsid);
+
+ /* Handle non-split brain cases */
+ list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
+ if (metadata_fsid) {
+ if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0
+ && memcmp(metadata_fsid, fs_devices->metadata_uuid,
+ BTRFS_FSID_SIZE) == 0)
+ return fs_devices;
+ } else {
+ if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
+ return fs_devices;
+ }
+ }
+ return NULL;
+}
+
+static struct btrfs_fs_devices *find_fsid_with_metadata_uuid(
+ struct btrfs_super_block *disk_super)
+{
+
+ struct btrfs_fs_devices *fs_devices;
+
+ /*
+ * Handle scanned device having completed its fsid change but
+ * belonging to a fs_devices that was created by first scanning
+ * a device which didn't have its fsid/metadata_uuid changed
+ * at all and the CHANGING_FSID_V2 flag set.
+ */
+ list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
+ if (fs_devices->fsid_change &&
+ memcmp(disk_super->metadata_uuid, fs_devices->fsid,
+ BTRFS_FSID_SIZE) == 0 &&
+ memcmp(fs_devices->fsid, fs_devices->metadata_uuid,
+ BTRFS_FSID_SIZE) == 0) {
+ return fs_devices;
+ }
+ }
+ /*
+ * Handle scanned device having completed its fsid change but
+ * belonging to a fs_devices that was created by a device that
+ * has an outdated pair of fsid/metadata_uuid and
+ * CHANGING_FSID_V2 flag set.
+ */
+ list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
+ if (fs_devices->fsid_change &&
+ memcmp(fs_devices->metadata_uuid,
+ fs_devices->fsid, BTRFS_FSID_SIZE) != 0 &&
+ memcmp(disk_super->metadata_uuid, fs_devices->metadata_uuid,
+ BTRFS_FSID_SIZE) == 0) {
+ return fs_devices;
+ }
+ }
+
+ return find_fsid(disk_super->fsid, disk_super->metadata_uuid);
+}
+
+
+static int
+btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
+ int flush, struct block_device **bdev,
+ struct btrfs_super_block **disk_super)
+{
+ int ret;
+
+ *bdev = blkdev_get_by_path(device_path, flags, holder);
+
+ if (IS_ERR(*bdev)) {
+ ret = PTR_ERR(*bdev);
+ goto error;
+ }
+
+ if (flush)
+ sync_blockdev(*bdev);
+ ret = set_blocksize(*bdev, BTRFS_BDEV_BLOCKSIZE);
+ if (ret) {
+ blkdev_put(*bdev, flags);
+ goto error;
+ }
+ invalidate_bdev(*bdev);
+ *disk_super = btrfs_read_dev_super(*bdev);
+ if (IS_ERR(*disk_super)) {
+ ret = PTR_ERR(*disk_super);
+ blkdev_put(*bdev, flags);
+ goto error;
+ }
+
+ return 0;
+
+error:
+ *bdev = NULL;
+ return ret;
+}
+
+/**
+ * Search and remove all stale devices (which are not mounted).
+ * When both inputs are NULL, it will search and release all stale devices.
+ *
+ * @devt: Optional. When provided will it release all unmounted devices
+ * matching this devt only.
+ * @skip_device: Optional. Will skip this device when searching for the stale
+ * devices.
+ *
+ * Return: 0 for success or if @devt is 0.
+ * -EBUSY if @devt is a mounted device.
+ * -ENOENT if @devt does not match any device in the list.
+ */
+static int btrfs_free_stale_devices(dev_t devt, struct btrfs_device *skip_device)
+{
+ struct btrfs_fs_devices *fs_devices, *tmp_fs_devices;
+ struct btrfs_device *device, *tmp_device;
+ int ret = 0;
+
+ lockdep_assert_held(&uuid_mutex);
+
+ if (devt)
+ ret = -ENOENT;
+
+ list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) {
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ list_for_each_entry_safe(device, tmp_device,
+ &fs_devices->devices, dev_list) {
+ if (skip_device && skip_device == device)
+ continue;
+ if (devt && devt != device->devt)
+ continue;
+ if (fs_devices->opened) {
+ /* for an already deleted device return 0 */
+ if (devt && ret != 0)
+ ret = -EBUSY;
+ break;
+ }
+
+ /* delete the stale device */
+ fs_devices->num_devices--;
+ list_del(&device->dev_list);
+ btrfs_free_device(device);
+
+ ret = 0;
+ }
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ if (fs_devices->num_devices == 0) {
+ btrfs_sysfs_remove_fsid(fs_devices);
+ list_del(&fs_devices->fs_list);
+ free_fs_devices(fs_devices);
+ }
+ }
+
+ return ret;
+}
+
+/*
+ * This is only used on mount, and we are protected from competing things
+ * messing with our fs_devices by the uuid_mutex, thus we do not need the
+ * fs_devices->device_list_mutex here.
+ */
+static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
+ struct btrfs_device *device, fmode_t flags,
+ void *holder)
+{
+ struct block_device *bdev;
+ struct btrfs_super_block *disk_super;
+ u64 devid;
+ int ret;
+
+ if (device->bdev)
+ return -EINVAL;
+ if (!device->name)
+ return -EINVAL;
+
+ ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
+ &bdev, &disk_super);
+ if (ret)
+ return ret;
+
+ devid = btrfs_stack_device_id(&disk_super->dev_item);
+ if (devid != device->devid)
+ goto error_free_page;
+
+ if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE))
+ goto error_free_page;
+
+ device->generation = btrfs_super_generation(disk_super);
+
+ if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
+ if (btrfs_super_incompat_flags(disk_super) &
+ BTRFS_FEATURE_INCOMPAT_METADATA_UUID) {
+ pr_err(
+ "BTRFS: Invalid seeding and uuid-changed device detected\n");
+ goto error_free_page;
+ }
+
+ clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
+ fs_devices->seeding = true;
+ } else {
+ if (bdev_read_only(bdev))
+ clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
+ else
+ set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
+ }
+
+ if (!bdev_nonrot(bdev))
+ fs_devices->rotating = true;
+
+ device->bdev = bdev;
+ clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
+ device->mode = flags;
+
+ fs_devices->open_devices++;
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
+ device->devid != BTRFS_DEV_REPLACE_DEVID) {
+ fs_devices->rw_devices++;
+ list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list);
+ }
+ btrfs_release_disk_super(disk_super);
+
+ return 0;
+
+error_free_page:
+ btrfs_release_disk_super(disk_super);
+ blkdev_put(bdev, flags);
+
+ return -EINVAL;
+}
+
+u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb)
+{
+ bool has_metadata_uuid = (btrfs_super_incompat_flags(sb) &
+ BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
+
+ return has_metadata_uuid ? sb->metadata_uuid : sb->fsid;
+}
+
+/*
+ * Handle scanned device having its CHANGING_FSID_V2 flag set and the fs_devices
+ * being created with a disk that has already completed its fsid change. Such
+ * disk can belong to an fs which has its FSID changed or to one which doesn't.
+ * Handle both cases here.
+ */
+static struct btrfs_fs_devices *find_fsid_inprogress(
+ struct btrfs_super_block *disk_super)
+{
+ struct btrfs_fs_devices *fs_devices;
+
+ list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
+ if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid,
+ BTRFS_FSID_SIZE) != 0 &&
+ memcmp(fs_devices->metadata_uuid, disk_super->fsid,
+ BTRFS_FSID_SIZE) == 0 && !fs_devices->fsid_change) {
+ return fs_devices;
+ }
+ }
+
+ return find_fsid(disk_super->fsid, NULL);
+}
+
+
+static struct btrfs_fs_devices *find_fsid_changed(
+ struct btrfs_super_block *disk_super)
+{
+ struct btrfs_fs_devices *fs_devices;
+
+ /*
+ * Handles the case where scanned device is part of an fs that had
+ * multiple successful changes of FSID but currently device didn't
+ * observe it. Meaning our fsid will be different than theirs. We need
+ * to handle two subcases :
+ * 1 - The fs still continues to have different METADATA/FSID uuids.
+ * 2 - The fs is switched back to its original FSID (METADATA/FSID
+ * are equal).
+ */
+ list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
+ /* Changed UUIDs */
+ if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid,
+ BTRFS_FSID_SIZE) != 0 &&
+ memcmp(fs_devices->metadata_uuid, disk_super->metadata_uuid,
+ BTRFS_FSID_SIZE) == 0 &&
+ memcmp(fs_devices->fsid, disk_super->fsid,
+ BTRFS_FSID_SIZE) != 0)
+ return fs_devices;
+
+ /* Unchanged UUIDs */
+ if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid,
+ BTRFS_FSID_SIZE) == 0 &&
+ memcmp(fs_devices->fsid, disk_super->metadata_uuid,
+ BTRFS_FSID_SIZE) == 0)
+ return fs_devices;
+ }
+
+ return NULL;
+}
+
+static struct btrfs_fs_devices *find_fsid_reverted_metadata(
+ struct btrfs_super_block *disk_super)
+{
+ struct btrfs_fs_devices *fs_devices;
+
+ /*
+ * Handle the case where the scanned device is part of an fs whose last
+ * metadata UUID change reverted it to the original FSID. At the same
+ * time * fs_devices was first created by another constitutent device
+ * which didn't fully observe the operation. This results in an
+ * btrfs_fs_devices created with metadata/fsid different AND
+ * btrfs_fs_devices::fsid_change set AND the metadata_uuid of the
+ * fs_devices equal to the FSID of the disk.
+ */
+ list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
+ if (memcmp(fs_devices->fsid, fs_devices->metadata_uuid,
+ BTRFS_FSID_SIZE) != 0 &&
+ memcmp(fs_devices->metadata_uuid, disk_super->fsid,
+ BTRFS_FSID_SIZE) == 0 &&
+ fs_devices->fsid_change)
+ return fs_devices;
+ }
+
+ return NULL;
+}
+/*
+ * Add new device to list of registered devices
+ *
+ * Returns:
+ * device pointer which was just added or updated when successful
+ * error pointer when failed
+ */
+static noinline struct btrfs_device *device_list_add(const char *path,
+ struct btrfs_super_block *disk_super,
+ bool *new_device_added)
+{
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *fs_devices = NULL;
+ struct rcu_string *name;
+ u64 found_transid = btrfs_super_generation(disk_super);
+ u64 devid = btrfs_stack_device_id(&disk_super->dev_item);
+ dev_t path_devt;
+ int error;
+ bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
+ BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
+ bool fsid_change_in_progress = (btrfs_super_flags(disk_super) &
+ BTRFS_SUPER_FLAG_CHANGING_FSID_V2);
+
+ error = lookup_bdev(path, &path_devt);
+ if (error) {
+ btrfs_err(NULL, "failed to lookup block device for path %s: %d",
+ path, error);
+ return ERR_PTR(error);
+ }
+
+ if (fsid_change_in_progress) {
+ if (!has_metadata_uuid)
+ fs_devices = find_fsid_inprogress(disk_super);
+ else
+ fs_devices = find_fsid_changed(disk_super);
+ } else if (has_metadata_uuid) {
+ fs_devices = find_fsid_with_metadata_uuid(disk_super);
+ } else {
+ fs_devices = find_fsid_reverted_metadata(disk_super);
+ if (!fs_devices)
+ fs_devices = find_fsid(disk_super->fsid, NULL);
+ }
+
+
+ if (!fs_devices) {
+ if (has_metadata_uuid)
+ fs_devices = alloc_fs_devices(disk_super->fsid,
+ disk_super->metadata_uuid);
+ else
+ fs_devices = alloc_fs_devices(disk_super->fsid, NULL);
+
+ if (IS_ERR(fs_devices))
+ return ERR_CAST(fs_devices);
+
+ fs_devices->fsid_change = fsid_change_in_progress;
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ list_add(&fs_devices->fs_list, &fs_uuids);
+
+ device = NULL;
+ } else {
+ struct btrfs_dev_lookup_args args = {
+ .devid = devid,
+ .uuid = disk_super->dev_item.uuid,
+ };
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ device = btrfs_find_device(fs_devices, &args);
+
+ /*
+ * If this disk has been pulled into an fs devices created by
+ * a device which had the CHANGING_FSID_V2 flag then replace the
+ * metadata_uuid/fsid values of the fs_devices.
+ */
+ if (fs_devices->fsid_change &&
+ found_transid > fs_devices->latest_generation) {
+ memcpy(fs_devices->fsid, disk_super->fsid,
+ BTRFS_FSID_SIZE);
+
+ if (has_metadata_uuid)
+ memcpy(fs_devices->metadata_uuid,
+ disk_super->metadata_uuid,
+ BTRFS_FSID_SIZE);
+ else
+ memcpy(fs_devices->metadata_uuid,
+ disk_super->fsid, BTRFS_FSID_SIZE);
+
+ fs_devices->fsid_change = false;
+ }
+ }
+
+ if (!device) {
+ if (fs_devices->opened) {
+ btrfs_err(NULL,
+ "device %s belongs to fsid %pU, and the fs is already mounted",
+ path, fs_devices->fsid);
+ mutex_unlock(&fs_devices->device_list_mutex);
+ return ERR_PTR(-EBUSY);
+ }
+
+ device = btrfs_alloc_device(NULL, &devid,
+ disk_super->dev_item.uuid);
+ if (IS_ERR(device)) {
+ mutex_unlock(&fs_devices->device_list_mutex);
+ /* we can safely leave the fs_devices entry around */
+ return device;
+ }
+
+ name = rcu_string_strdup(path, GFP_NOFS);
+ if (!name) {
+ btrfs_free_device(device);
+ mutex_unlock(&fs_devices->device_list_mutex);
+ return ERR_PTR(-ENOMEM);
+ }
+ rcu_assign_pointer(device->name, name);
+ device->devt = path_devt;
+
+ list_add_rcu(&device->dev_list, &fs_devices->devices);
+ fs_devices->num_devices++;
+
+ device->fs_devices = fs_devices;
+ *new_device_added = true;
+
+ if (disk_super->label[0])
+ pr_info(
+ "BTRFS: device label %s devid %llu transid %llu %s scanned by %s (%d)\n",
+ disk_super->label, devid, found_transid, path,
+ current->comm, task_pid_nr(current));
+ else
+ pr_info(
+ "BTRFS: device fsid %pU devid %llu transid %llu %s scanned by %s (%d)\n",
+ disk_super->fsid, devid, found_transid, path,
+ current->comm, task_pid_nr(current));
+
+ } else if (!device->name || strcmp(device->name->str, path)) {
+ /*
+ * When FS is already mounted.
+ * 1. If you are here and if the device->name is NULL that
+ * means this device was missing at time of FS mount.
+ * 2. If you are here and if the device->name is different
+ * from 'path' that means either
+ * a. The same device disappeared and reappeared with
+ * different name. or
+ * b. The missing-disk-which-was-replaced, has
+ * reappeared now.
+ *
+ * We must allow 1 and 2a above. But 2b would be a spurious
+ * and unintentional.
+ *
+ * Further in case of 1 and 2a above, the disk at 'path'
+ * would have missed some transaction when it was away and
+ * in case of 2a the stale bdev has to be updated as well.
+ * 2b must not be allowed at all time.
+ */
+
+ /*
+ * For now, we do allow update to btrfs_fs_device through the
+ * btrfs dev scan cli after FS has been mounted. We're still
+ * tracking a problem where systems fail mount by subvolume id
+ * when we reject replacement on a mounted FS.
+ */
+ if (!fs_devices->opened && found_transid < device->generation) {
+ /*
+ * That is if the FS is _not_ mounted and if you
+ * are here, that means there is more than one
+ * disk with same uuid and devid.We keep the one
+ * with larger generation number or the last-in if
+ * generation are equal.
+ */
+ mutex_unlock(&fs_devices->device_list_mutex);
+ btrfs_err(NULL,
+"device %s already registered with a higher generation, found %llu expect %llu",
+ path, found_transid, device->generation);
+ return ERR_PTR(-EEXIST);
+ }
+
+ /*
+ * We are going to replace the device path for a given devid,
+ * make sure it's the same device if the device is mounted
+ *
+ * NOTE: the device->fs_info may not be reliable here so pass
+ * in a NULL to message helpers instead. This avoids a possible
+ * use-after-free when the fs_info and fs_info->sb are already
+ * torn down.
+ */
+ if (device->bdev) {
+ if (device->devt != path_devt) {
+ mutex_unlock(&fs_devices->device_list_mutex);
+ btrfs_warn_in_rcu(NULL,
+ "duplicate device %s devid %llu generation %llu scanned by %s (%d)",
+ path, devid, found_transid,
+ current->comm,
+ task_pid_nr(current));
+ return ERR_PTR(-EEXIST);
+ }
+ btrfs_info_in_rcu(NULL,
+ "devid %llu device path %s changed to %s scanned by %s (%d)",
+ devid, rcu_str_deref(device->name),
+ path, current->comm,
+ task_pid_nr(current));
+ }
+
+ name = rcu_string_strdup(path, GFP_NOFS);
+ if (!name) {
+ mutex_unlock(&fs_devices->device_list_mutex);
+ return ERR_PTR(-ENOMEM);
+ }
+ rcu_string_free(device->name);
+ rcu_assign_pointer(device->name, name);
+ if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
+ fs_devices->missing_devices--;
+ clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
+ }
+ device->devt = path_devt;
+ }
+
+ /*
+ * Unmount does not free the btrfs_device struct but would zero
+ * generation along with most of the other members. So just update
+ * it back. We need it to pick the disk with largest generation
+ * (as above).
+ */
+ if (!fs_devices->opened) {
+ device->generation = found_transid;
+ fs_devices->latest_generation = max_t(u64, found_transid,
+ fs_devices->latest_generation);
+ }
+
+ fs_devices->total_devices = btrfs_super_num_devices(disk_super);
+
+ mutex_unlock(&fs_devices->device_list_mutex);
+ return device;
+}
+
+static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
+{
+ struct btrfs_fs_devices *fs_devices;
+ struct btrfs_device *device;
+ struct btrfs_device *orig_dev;
+ int ret = 0;
+
+ lockdep_assert_held(&uuid_mutex);
+
+ fs_devices = alloc_fs_devices(orig->fsid, NULL);
+ if (IS_ERR(fs_devices))
+ return fs_devices;
+
+ fs_devices->total_devices = orig->total_devices;
+
+ list_for_each_entry(orig_dev, &orig->devices, dev_list) {
+ struct rcu_string *name;
+
+ device = btrfs_alloc_device(NULL, &orig_dev->devid,
+ orig_dev->uuid);
+ if (IS_ERR(device)) {
+ ret = PTR_ERR(device);
+ goto error;
+ }
+
+ /*
+ * This is ok to do without rcu read locked because we hold the
+ * uuid mutex so nothing we touch in here is going to disappear.
+ */
+ if (orig_dev->name) {
+ name = rcu_string_strdup(orig_dev->name->str,
+ GFP_KERNEL);
+ if (!name) {
+ btrfs_free_device(device);
+ ret = -ENOMEM;
+ goto error;
+ }
+ rcu_assign_pointer(device->name, name);
+ }
+
+ if (orig_dev->zone_info) {
+ struct btrfs_zoned_device_info *zone_info;
+
+ zone_info = btrfs_clone_dev_zone_info(orig_dev);
+ if (!zone_info) {
+ btrfs_free_device(device);
+ ret = -ENOMEM;
+ goto error;
+ }
+ device->zone_info = zone_info;
+ }
+
+ list_add(&device->dev_list, &fs_devices->devices);
+ device->fs_devices = fs_devices;
+ fs_devices->num_devices++;
+ }
+ return fs_devices;
+error:
+ free_fs_devices(fs_devices);
+ return ERR_PTR(ret);
+}
+
+static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices,
+ struct btrfs_device **latest_dev)
+{
+ struct btrfs_device *device, *next;
+
+ /* This is the initialized path, it is safe to release the devices. */
+ list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
+ if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)) {
+ if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT,
+ &device->dev_state) &&
+ !test_bit(BTRFS_DEV_STATE_MISSING,
+ &device->dev_state) &&
+ (!*latest_dev ||
+ device->generation > (*latest_dev)->generation)) {
+ *latest_dev = device;
+ }
+ continue;
+ }
+
+ /*
+ * We have already validated the presence of BTRFS_DEV_REPLACE_DEVID,
+ * in btrfs_init_dev_replace() so just continue.
+ */
+ if (device->devid == BTRFS_DEV_REPLACE_DEVID)
+ continue;
+
+ if (device->bdev) {
+ blkdev_put(device->bdev, device->mode);
+ device->bdev = NULL;
+ fs_devices->open_devices--;
+ }
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ list_del_init(&device->dev_alloc_list);
+ clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
+ fs_devices->rw_devices--;
+ }
+ list_del_init(&device->dev_list);
+ fs_devices->num_devices--;
+ btrfs_free_device(device);
+ }
+
+}
+
+/*
+ * After we have read the system tree and know devids belonging to this
+ * filesystem, remove the device which does not belong there.
+ */
+void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices)
+{
+ struct btrfs_device *latest_dev = NULL;
+ struct btrfs_fs_devices *seed_dev;
+
+ mutex_lock(&uuid_mutex);
+ __btrfs_free_extra_devids(fs_devices, &latest_dev);
+
+ list_for_each_entry(seed_dev, &fs_devices->seed_list, seed_list)
+ __btrfs_free_extra_devids(seed_dev, &latest_dev);
+
+ fs_devices->latest_dev = latest_dev;
+
+ mutex_unlock(&uuid_mutex);
+}
+
+static void btrfs_close_bdev(struct btrfs_device *device)
+{
+ if (!device->bdev)
+ return;
+
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ sync_blockdev(device->bdev);
+ invalidate_bdev(device->bdev);
+ }
+
+ blkdev_put(device->bdev, device->mode);
+}
+
+static void btrfs_close_one_device(struct btrfs_device *device)
+{
+ struct btrfs_fs_devices *fs_devices = device->fs_devices;
+
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
+ device->devid != BTRFS_DEV_REPLACE_DEVID) {
+ list_del_init(&device->dev_alloc_list);
+ fs_devices->rw_devices--;
+ }
+
+ if (device->devid == BTRFS_DEV_REPLACE_DEVID)
+ clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
+
+ if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
+ clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
+ fs_devices->missing_devices--;
+ }
+
+ btrfs_close_bdev(device);
+ if (device->bdev) {
+ fs_devices->open_devices--;
+ device->bdev = NULL;
+ }
+ clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
+ btrfs_destroy_dev_zone_info(device);
+
+ device->fs_info = NULL;
+ atomic_set(&device->dev_stats_ccnt, 0);
+ extent_io_tree_release(&device->alloc_state);
+
+ /*
+ * Reset the flush error record. We might have a transient flush error
+ * in this mount, and if so we aborted the current transaction and set
+ * the fs to an error state, guaranteeing no super blocks can be further
+ * committed. However that error might be transient and if we unmount the
+ * filesystem and mount it again, we should allow the mount to succeed
+ * (btrfs_check_rw_degradable() should not fail) - if after mounting the
+ * filesystem again we still get flush errors, then we will again abort
+ * any transaction and set the error state, guaranteeing no commits of
+ * unsafe super blocks.
+ */
+ device->last_flush_error = 0;
+
+ /* Verify the device is back in a pristine state */
+ ASSERT(!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state));
+ ASSERT(!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state));
+ ASSERT(list_empty(&device->dev_alloc_list));
+ ASSERT(list_empty(&device->post_commit_list));
+}
+
+static void close_fs_devices(struct btrfs_fs_devices *fs_devices)
+{
+ struct btrfs_device *device, *tmp;
+
+ lockdep_assert_held(&uuid_mutex);
+
+ if (--fs_devices->opened > 0)
+ return;
+
+ list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list)
+ btrfs_close_one_device(device);
+
+ WARN_ON(fs_devices->open_devices);
+ WARN_ON(fs_devices->rw_devices);
+ fs_devices->opened = 0;
+ fs_devices->seeding = false;
+ fs_devices->fs_info = NULL;
+}
+
+void btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
+{
+ LIST_HEAD(list);
+ struct btrfs_fs_devices *tmp;
+
+ mutex_lock(&uuid_mutex);
+ close_fs_devices(fs_devices);
+ if (!fs_devices->opened) {
+ list_splice_init(&fs_devices->seed_list, &list);
+
+ /*
+ * If the struct btrfs_fs_devices is not assembled with any
+ * other device, it can be re-initialized during the next mount
+ * without the needing device-scan step. Therefore, it can be
+ * fully freed.
+ */
+ if (fs_devices->num_devices == 1) {
+ list_del(&fs_devices->fs_list);
+ free_fs_devices(fs_devices);
+ }
+ }
+
+
+ list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) {
+ close_fs_devices(fs_devices);
+ list_del(&fs_devices->seed_list);
+ free_fs_devices(fs_devices);
+ }
+ mutex_unlock(&uuid_mutex);
+}
+
+static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
+ fmode_t flags, void *holder)
+{
+ struct btrfs_device *device;
+ struct btrfs_device *latest_dev = NULL;
+ struct btrfs_device *tmp_device;
+
+ flags |= FMODE_EXCL;
+
+ list_for_each_entry_safe(device, tmp_device, &fs_devices->devices,
+ dev_list) {
+ int ret;
+
+ ret = btrfs_open_one_device(fs_devices, device, flags, holder);
+ if (ret == 0 &&
+ (!latest_dev || device->generation > latest_dev->generation)) {
+ latest_dev = device;
+ } else if (ret == -ENODATA) {
+ fs_devices->num_devices--;
+ list_del(&device->dev_list);
+ btrfs_free_device(device);
+ }
+ }
+ if (fs_devices->open_devices == 0)
+ return -EINVAL;
+
+ fs_devices->opened = 1;
+ fs_devices->latest_dev = latest_dev;
+ fs_devices->total_rw_bytes = 0;
+ fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR;
+ fs_devices->read_policy = BTRFS_READ_POLICY_PID;
+
+ return 0;
+}
+
+static int devid_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
+{
+ const struct btrfs_device *dev1, *dev2;
+
+ dev1 = list_entry(a, struct btrfs_device, dev_list);
+ dev2 = list_entry(b, struct btrfs_device, dev_list);
+
+ if (dev1->devid < dev2->devid)
+ return -1;
+ else if (dev1->devid > dev2->devid)
+ return 1;
+ return 0;
+}
+
+int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
+ fmode_t flags, void *holder)
+{
+ int ret;
+
+ lockdep_assert_held(&uuid_mutex);
+ /*
+ * The device_list_mutex cannot be taken here in case opening the
+ * underlying device takes further locks like open_mutex.
+ *
+ * We also don't need the lock here as this is called during mount and
+ * exclusion is provided by uuid_mutex
+ */
+
+ if (fs_devices->opened) {
+ fs_devices->opened++;
+ ret = 0;
+ } else {
+ list_sort(NULL, &fs_devices->devices, devid_cmp);
+ ret = open_fs_devices(fs_devices, flags, holder);
+ }
+
+ return ret;
+}
+
+void btrfs_release_disk_super(struct btrfs_super_block *super)
+{
+ struct page *page = virt_to_page(super);
+
+ put_page(page);
+}
+
+static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
+ u64 bytenr, u64 bytenr_orig)
+{
+ struct btrfs_super_block *disk_super;
+ struct page *page;
+ void *p;
+ pgoff_t index;
+
+ /* make sure our super fits in the device */
+ if (bytenr + PAGE_SIZE >= bdev_nr_bytes(bdev))
+ return ERR_PTR(-EINVAL);
+
+ /* make sure our super fits in the page */
+ if (sizeof(*disk_super) > PAGE_SIZE)
+ return ERR_PTR(-EINVAL);
+
+ /* make sure our super doesn't straddle pages on disk */
+ index = bytenr >> PAGE_SHIFT;
+ if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index)
+ return ERR_PTR(-EINVAL);
+
+ /* pull in the page with our super */
+ page = read_cache_page_gfp(bdev->bd_inode->i_mapping, index, GFP_KERNEL);
+
+ if (IS_ERR(page))
+ return ERR_CAST(page);
+
+ p = page_address(page);
+
+ /* align our pointer to the offset of the super block */
+ disk_super = p + offset_in_page(bytenr);
+
+ if (btrfs_super_bytenr(disk_super) != bytenr_orig ||
+ btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
+ btrfs_release_disk_super(p);
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1])
+ disk_super->label[BTRFS_LABEL_SIZE - 1] = 0;
+
+ return disk_super;
+}
+
+int btrfs_forget_devices(dev_t devt)
+{
+ int ret;
+
+ mutex_lock(&uuid_mutex);
+ ret = btrfs_free_stale_devices(devt, NULL);
+ mutex_unlock(&uuid_mutex);
+
+ return ret;
+}
+
+/*
+ * Look for a btrfs signature on a device. This may be called out of the mount path
+ * and we are not allowed to call set_blocksize during the scan. The superblock
+ * is read via pagecache
+ */
+struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags,
+ void *holder)
+{
+ struct btrfs_super_block *disk_super;
+ bool new_device_added = false;
+ struct btrfs_device *device = NULL;
+ struct block_device *bdev;
+ u64 bytenr, bytenr_orig;
+ int ret;
+
+ lockdep_assert_held(&uuid_mutex);
+
+ /*
+ * we would like to check all the supers, but that would make
+ * a btrfs mount succeed after a mkfs from a different FS.
+ * So, we need to add a special mount option to scan for
+ * later supers, using BTRFS_SUPER_MIRROR_MAX instead
+ */
+
+ /*
+ * Avoid using flag |= FMODE_EXCL here, as the systemd-udev may
+ * initiate the device scan which may race with the user's mount
+ * or mkfs command, resulting in failure.
+ * Since the device scan is solely for reading purposes, there is
+ * no need for FMODE_EXCL. Additionally, the devices are read again
+ * during the mount process. It is ok to get some inconsistent
+ * values temporarily, as the device paths of the fsid are the only
+ * required information for assembling the volume.
+ */
+ bdev = blkdev_get_by_path(path, flags, holder);
+ if (IS_ERR(bdev))
+ return ERR_CAST(bdev);
+
+ bytenr_orig = btrfs_sb_offset(0);
+ ret = btrfs_sb_log_location_bdev(bdev, 0, READ, &bytenr);
+ if (ret) {
+ device = ERR_PTR(ret);
+ goto error_bdev_put;
+ }
+
+ disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr_orig);
+ if (IS_ERR(disk_super)) {
+ device = ERR_CAST(disk_super);
+ goto error_bdev_put;
+ }
+
+ device = device_list_add(path, disk_super, &new_device_added);
+ if (!IS_ERR(device) && new_device_added)
+ btrfs_free_stale_devices(device->devt, device);
+
+ btrfs_release_disk_super(disk_super);
+
+error_bdev_put:
+ blkdev_put(bdev, flags);
+
+ return device;
+}
+
+/*
+ * Try to find a chunk that intersects [start, start + len] range and when one
+ * such is found, record the end of it in *start
+ */
+static bool contains_pending_extent(struct btrfs_device *device, u64 *start,
+ u64 len)
+{
+ u64 physical_start, physical_end;
+
+ lockdep_assert_held(&device->fs_info->chunk_mutex);
+
+ if (!find_first_extent_bit(&device->alloc_state, *start,
+ &physical_start, &physical_end,
+ CHUNK_ALLOCATED, NULL)) {
+
+ if (in_range(physical_start, *start, len) ||
+ in_range(*start, physical_start,
+ physical_end - physical_start)) {
+ *start = physical_end + 1;
+ return true;
+ }
+ }
+ return false;
+}
+
+static u64 dev_extent_search_start(struct btrfs_device *device, u64 start)
+{
+ switch (device->fs_devices->chunk_alloc_policy) {
+ case BTRFS_CHUNK_ALLOC_REGULAR:
+ return max_t(u64, start, BTRFS_DEVICE_RANGE_RESERVED);
+ case BTRFS_CHUNK_ALLOC_ZONED:
+ /*
+ * We don't care about the starting region like regular
+ * allocator, because we anyway use/reserve the first two zones
+ * for superblock logging.
+ */
+ return ALIGN(start, device->zone_info->zone_size);
+ default:
+ BUG();
+ }
+}
+
+static bool dev_extent_hole_check_zoned(struct btrfs_device *device,
+ u64 *hole_start, u64 *hole_size,
+ u64 num_bytes)
+{
+ u64 zone_size = device->zone_info->zone_size;
+ u64 pos;
+ int ret;
+ bool changed = false;
+
+ ASSERT(IS_ALIGNED(*hole_start, zone_size));
+
+ while (*hole_size > 0) {
+ pos = btrfs_find_allocatable_zones(device, *hole_start,
+ *hole_start + *hole_size,
+ num_bytes);
+ if (pos != *hole_start) {
+ *hole_size = *hole_start + *hole_size - pos;
+ *hole_start = pos;
+ changed = true;
+ if (*hole_size < num_bytes)
+ break;
+ }
+
+ ret = btrfs_ensure_empty_zones(device, pos, num_bytes);
+
+ /* Range is ensured to be empty */
+ if (!ret)
+ return changed;
+
+ /* Given hole range was invalid (outside of device) */
+ if (ret == -ERANGE) {
+ *hole_start += *hole_size;
+ *hole_size = 0;
+ return true;
+ }
+
+ *hole_start += zone_size;
+ *hole_size -= zone_size;
+ changed = true;
+ }
+
+ return changed;
+}
+
+/**
+ * dev_extent_hole_check - check if specified hole is suitable for allocation
+ * @device: the device which we have the hole
+ * @hole_start: starting position of the hole
+ * @hole_size: the size of the hole
+ * @num_bytes: the size of the free space that we need
+ *
+ * This function may modify @hole_start and @hole_size to reflect the suitable
+ * position for allocation. Returns 1 if hole position is updated, 0 otherwise.
+ */
+static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start,
+ u64 *hole_size, u64 num_bytes)
+{
+ bool changed = false;
+ u64 hole_end = *hole_start + *hole_size;
+
+ for (;;) {
+ /*
+ * Check before we set max_hole_start, otherwise we could end up
+ * sending back this offset anyway.
+ */
+ if (contains_pending_extent(device, hole_start, *hole_size)) {
+ if (hole_end >= *hole_start)
+ *hole_size = hole_end - *hole_start;
+ else
+ *hole_size = 0;
+ changed = true;
+ }
+
+ switch (device->fs_devices->chunk_alloc_policy) {
+ case BTRFS_CHUNK_ALLOC_REGULAR:
+ /* No extra check */
+ break;
+ case BTRFS_CHUNK_ALLOC_ZONED:
+ if (dev_extent_hole_check_zoned(device, hole_start,
+ hole_size, num_bytes)) {
+ changed = true;
+ /*
+ * The changed hole can contain pending extent.
+ * Loop again to check that.
+ */
+ continue;
+ }
+ break;
+ default:
+ BUG();
+ }
+
+ break;
+ }
+
+ return changed;
+}
+
+/*
+ * find_free_dev_extent_start - find free space in the specified device
+ * @device: the device which we search the free space in
+ * @num_bytes: the size of the free space that we need
+ * @search_start: the position from which to begin the search
+ * @start: store the start of the free space.
+ * @len: the size of the free space. that we find, or the size
+ * of the max free space if we don't find suitable free space
+ *
+ * this uses a pretty simple search, the expectation is that it is
+ * called very infrequently and that a given device has a small number
+ * of extents
+ *
+ * @start is used to store the start of the free space if we find. But if we
+ * don't find suitable free space, it will be used to store the start position
+ * of the max free space.
+ *
+ * @len is used to store the size of the free space that we find.
+ * But if we don't find suitable free space, it is used to store the size of
+ * the max free space.
+ *
+ * NOTE: This function will search *commit* root of device tree, and does extra
+ * check to ensure dev extents are not double allocated.
+ * This makes the function safe to allocate dev extents but may not report
+ * correct usable device space, as device extent freed in current transaction
+ * is not reported as available.
+ */
+static int find_free_dev_extent_start(struct btrfs_device *device,
+ u64 num_bytes, u64 search_start, u64 *start,
+ u64 *len)
+{
+ struct btrfs_fs_info *fs_info = device->fs_info;
+ struct btrfs_root *root = fs_info->dev_root;
+ struct btrfs_key key;
+ struct btrfs_dev_extent *dev_extent;
+ struct btrfs_path *path;
+ u64 hole_size;
+ u64 max_hole_start;
+ u64 max_hole_size;
+ u64 extent_end;
+ u64 search_end = device->total_bytes;
+ int ret;
+ int slot;
+ struct extent_buffer *l;
+
+ search_start = dev_extent_search_start(device, search_start);
+
+ WARN_ON(device->zone_info &&
+ !IS_ALIGNED(num_bytes, device->zone_info->zone_size));
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ max_hole_start = search_start;
+ max_hole_size = 0;
+
+again:
+ if (search_start >= search_end ||
+ test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
+ ret = -ENOSPC;
+ goto out;
+ }
+
+ path->reada = READA_FORWARD;
+ path->search_commit_root = 1;
+ path->skip_locking = 1;
+
+ key.objectid = device->devid;
+ key.offset = search_start;
+ key.type = BTRFS_DEV_EXTENT_KEY;
+
+ ret = btrfs_search_backwards(root, &key, path);
+ if (ret < 0)
+ goto out;
+
+ while (search_start < search_end) {
+ l = path->nodes[0];
+ slot = path->slots[0];
+ if (slot >= btrfs_header_nritems(l)) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret == 0)
+ continue;
+ if (ret < 0)
+ goto out;
+
+ break;
+ }
+ btrfs_item_key_to_cpu(l, &key, slot);
+
+ if (key.objectid < device->devid)
+ goto next;
+
+ if (key.objectid > device->devid)
+ break;
+
+ if (key.type != BTRFS_DEV_EXTENT_KEY)
+ goto next;
+
+ if (key.offset > search_end)
+ break;
+
+ if (key.offset > search_start) {
+ hole_size = key.offset - search_start;
+ dev_extent_hole_check(device, &search_start, &hole_size,
+ num_bytes);
+
+ if (hole_size > max_hole_size) {
+ max_hole_start = search_start;
+ max_hole_size = hole_size;
+ }
+
+ /*
+ * If this free space is greater than which we need,
+ * it must be the max free space that we have found
+ * until now, so max_hole_start must point to the start
+ * of this free space and the length of this free space
+ * is stored in max_hole_size. Thus, we return
+ * max_hole_start and max_hole_size and go back to the
+ * caller.
+ */
+ if (hole_size >= num_bytes) {
+ ret = 0;
+ goto out;
+ }
+ }
+
+ dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
+ extent_end = key.offset + btrfs_dev_extent_length(l,
+ dev_extent);
+ if (extent_end > search_start)
+ search_start = extent_end;
+next:
+ path->slots[0]++;
+ cond_resched();
+ }
+
+ /*
+ * At this point, search_start should be the end of
+ * allocated dev extents, and when shrinking the device,
+ * search_end may be smaller than search_start.
+ */
+ if (search_end > search_start) {
+ hole_size = search_end - search_start;
+ if (dev_extent_hole_check(device, &search_start, &hole_size,
+ num_bytes)) {
+ btrfs_release_path(path);
+ goto again;
+ }
+
+ if (hole_size > max_hole_size) {
+ max_hole_start = search_start;
+ max_hole_size = hole_size;
+ }
+ }
+
+ /* See above. */
+ if (max_hole_size < num_bytes)
+ ret = -ENOSPC;
+ else
+ ret = 0;
+
+ ASSERT(max_hole_start + max_hole_size <= search_end);
+out:
+ btrfs_free_path(path);
+ *start = max_hole_start;
+ if (len)
+ *len = max_hole_size;
+ return ret;
+}
+
+int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
+ u64 *start, u64 *len)
+{
+ /* FIXME use last free of some kind */
+ return find_free_dev_extent_start(device, num_bytes, 0, start, len);
+}
+
+static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_device *device,
+ u64 start, u64 *dev_extent_len)
+{
+ struct btrfs_fs_info *fs_info = device->fs_info;
+ struct btrfs_root *root = fs_info->dev_root;
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ struct extent_buffer *leaf = NULL;
+ struct btrfs_dev_extent *extent = NULL;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = device->devid;
+ key.offset = start;
+ key.type = BTRFS_DEV_EXTENT_KEY;
+again:
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret > 0) {
+ ret = btrfs_previous_item(root, path, key.objectid,
+ BTRFS_DEV_EXTENT_KEY);
+ if (ret)
+ goto out;
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ extent = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_dev_extent);
+ BUG_ON(found_key.offset > start || found_key.offset +
+ btrfs_dev_extent_length(leaf, extent) < start);
+ key = found_key;
+ btrfs_release_path(path);
+ goto again;
+ } else if (ret == 0) {
+ leaf = path->nodes[0];
+ extent = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_dev_extent);
+ } else {
+ goto out;
+ }
+
+ *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
+
+ ret = btrfs_del_item(trans, root, path);
+ if (ret == 0)
+ set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
+{
+ struct extent_map_tree *em_tree;
+ struct extent_map *em;
+ struct rb_node *n;
+ u64 ret = 0;
+
+ em_tree = &fs_info->mapping_tree;
+ read_lock(&em_tree->lock);
+ n = rb_last(&em_tree->map.rb_root);
+ if (n) {
+ em = rb_entry(n, struct extent_map, rb_node);
+ ret = em->start + em->len;
+ }
+ read_unlock(&em_tree->lock);
+
+ return ret;
+}
+
+static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
+ u64 *devid_ret)
+{
+ int ret;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ struct btrfs_path *path;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+ key.type = BTRFS_DEV_ITEM_KEY;
+ key.offset = (u64)-1;
+
+ ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
+ if (ret < 0)
+ goto error;
+
+ if (ret == 0) {
+ /* Corruption */
+ btrfs_err(fs_info, "corrupted chunk tree devid -1 matched");
+ ret = -EUCLEAN;
+ goto error;
+ }
+
+ ret = btrfs_previous_item(fs_info->chunk_root, path,
+ BTRFS_DEV_ITEMS_OBJECTID,
+ BTRFS_DEV_ITEM_KEY);
+ if (ret) {
+ *devid_ret = 1;
+ } else {
+ btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+ path->slots[0]);
+ *devid_ret = found_key.offset + 1;
+ }
+ ret = 0;
+error:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * the device information is stored in the chunk root
+ * the btrfs_device struct should be fully filled in
+ */
+static int btrfs_add_dev_item(struct btrfs_trans_handle *trans,
+ struct btrfs_device *device)
+{
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_dev_item *dev_item;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+ unsigned long ptr;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+ key.type = BTRFS_DEV_ITEM_KEY;
+ key.offset = device->devid;
+
+ btrfs_reserve_chunk_metadata(trans, true);
+ ret = btrfs_insert_empty_item(trans, trans->fs_info->chunk_root, path,
+ &key, sizeof(*dev_item));
+ btrfs_trans_release_chunk_metadata(trans);
+ if (ret)
+ goto out;
+
+ leaf = path->nodes[0];
+ dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
+
+ btrfs_set_device_id(leaf, dev_item, device->devid);
+ btrfs_set_device_generation(leaf, dev_item, 0);
+ btrfs_set_device_type(leaf, dev_item, device->type);
+ btrfs_set_device_io_align(leaf, dev_item, device->io_align);
+ btrfs_set_device_io_width(leaf, dev_item, device->io_width);
+ btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
+ btrfs_set_device_total_bytes(leaf, dev_item,
+ btrfs_device_get_disk_total_bytes(device));
+ btrfs_set_device_bytes_used(leaf, dev_item,
+ btrfs_device_get_bytes_used(device));
+ btrfs_set_device_group(leaf, dev_item, 0);
+ btrfs_set_device_seek_speed(leaf, dev_item, 0);
+ btrfs_set_device_bandwidth(leaf, dev_item, 0);
+ btrfs_set_device_start_offset(leaf, dev_item, 0);
+
+ ptr = btrfs_device_uuid(dev_item);
+ write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
+ ptr = btrfs_device_fsid(dev_item);
+ write_extent_buffer(leaf, trans->fs_info->fs_devices->metadata_uuid,
+ ptr, BTRFS_FSID_SIZE);
+ btrfs_mark_buffer_dirty(leaf);
+
+ ret = 0;
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * Function to update ctime/mtime for a given device path.
+ * Mainly used for ctime/mtime based probe like libblkid.
+ *
+ * We don't care about errors here, this is just to be kind to userspace.
+ */
+static void update_dev_time(const char *device_path)
+{
+ struct path path;
+ struct timespec64 now;
+ int ret;
+
+ ret = kern_path(device_path, LOOKUP_FOLLOW, &path);
+ if (ret)
+ return;
+
+ now = current_time(d_inode(path.dentry));
+ inode_update_time(d_inode(path.dentry), &now, S_MTIME | S_CTIME);
+ path_put(&path);
+}
+
+static int btrfs_rm_dev_item(struct btrfs_trans_handle *trans,
+ struct btrfs_device *device)
+{
+ struct btrfs_root *root = device->fs_info->chunk_root;
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+ key.type = BTRFS_DEV_ITEM_KEY;
+ key.offset = device->devid;
+
+ btrfs_reserve_chunk_metadata(trans, false);
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ btrfs_trans_release_chunk_metadata(trans);
+ if (ret) {
+ if (ret > 0)
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = btrfs_del_item(trans, root, path);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * Verify that @num_devices satisfies the RAID profile constraints in the whole
+ * filesystem. It's up to the caller to adjust that number regarding eg. device
+ * replace.
+ */
+static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
+ u64 num_devices)
+{
+ u64 all_avail;
+ unsigned seq;
+ int i;
+
+ do {
+ seq = read_seqbegin(&fs_info->profiles_lock);
+
+ all_avail = fs_info->avail_data_alloc_bits |
+ fs_info->avail_system_alloc_bits |
+ fs_info->avail_metadata_alloc_bits;
+ } while (read_seqretry(&fs_info->profiles_lock, seq));
+
+ for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
+ if (!(all_avail & btrfs_raid_array[i].bg_flag))
+ continue;
+
+ if (num_devices < btrfs_raid_array[i].devs_min)
+ return btrfs_raid_array[i].mindev_error;
+ }
+
+ return 0;
+}
+
+static struct btrfs_device * btrfs_find_next_active_device(
+ struct btrfs_fs_devices *fs_devs, struct btrfs_device *device)
+{
+ struct btrfs_device *next_device;
+
+ list_for_each_entry(next_device, &fs_devs->devices, dev_list) {
+ if (next_device != device &&
+ !test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state)
+ && next_device->bdev)
+ return next_device;
+ }
+
+ return NULL;
+}
+
+/*
+ * Helper function to check if the given device is part of s_bdev / latest_dev
+ * and replace it with the provided or the next active device, in the context
+ * where this function called, there should be always be another device (or
+ * this_dev) which is active.
+ */
+void __cold btrfs_assign_next_active_device(struct btrfs_device *device,
+ struct btrfs_device *next_device)
+{
+ struct btrfs_fs_info *fs_info = device->fs_info;
+
+ if (!next_device)
+ next_device = btrfs_find_next_active_device(fs_info->fs_devices,
+ device);
+ ASSERT(next_device);
+
+ if (fs_info->sb->s_bdev &&
+ (fs_info->sb->s_bdev == device->bdev))
+ fs_info->sb->s_bdev = next_device->bdev;
+
+ if (fs_info->fs_devices->latest_dev->bdev == device->bdev)
+ fs_info->fs_devices->latest_dev = next_device;
+}
+
+/*
+ * Return btrfs_fs_devices::num_devices excluding the device that's being
+ * currently replaced.
+ */
+static u64 btrfs_num_devices(struct btrfs_fs_info *fs_info)
+{
+ u64 num_devices = fs_info->fs_devices->num_devices;
+
+ down_read(&fs_info->dev_replace.rwsem);
+ if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
+ ASSERT(num_devices > 1);
+ num_devices--;
+ }
+ up_read(&fs_info->dev_replace.rwsem);
+
+ return num_devices;
+}
+
+void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
+ struct block_device *bdev,
+ const char *device_path)
+{
+ struct btrfs_super_block *disk_super;
+ int copy_num;
+
+ if (!bdev)
+ return;
+
+ for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX; copy_num++) {
+ struct page *page;
+ int ret;
+
+ disk_super = btrfs_read_dev_one_super(bdev, copy_num, false);
+ if (IS_ERR(disk_super))
+ continue;
+
+ if (bdev_is_zoned(bdev)) {
+ btrfs_reset_sb_log_zones(bdev, copy_num);
+ continue;
+ }
+
+ memset(&disk_super->magic, 0, sizeof(disk_super->magic));
+
+ page = virt_to_page(disk_super);
+ set_page_dirty(page);
+ lock_page(page);
+ /* write_on_page() unlocks the page */
+ ret = write_one_page(page);
+ if (ret)
+ btrfs_warn(fs_info,
+ "error clearing superblock number %d (%d)",
+ copy_num, ret);
+ btrfs_release_disk_super(disk_super);
+
+ }
+
+ /* Notify udev that device has changed */
+ btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
+
+ /* Update ctime/mtime for device path for libblkid */
+ update_dev_time(device_path);
+}
+
+int btrfs_rm_device(struct btrfs_fs_info *fs_info,
+ struct btrfs_dev_lookup_args *args,
+ struct block_device **bdev, fmode_t *mode)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *cur_devices;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ u64 num_devices;
+ int ret = 0;
+
+ if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
+ btrfs_err(fs_info, "device remove not supported on extent tree v2 yet");
+ return -EINVAL;
+ }
+
+ /*
+ * The device list in fs_devices is accessed without locks (neither
+ * uuid_mutex nor device_list_mutex) as it won't change on a mounted
+ * filesystem and another device rm cannot run.
+ */
+ num_devices = btrfs_num_devices(fs_info);
+
+ ret = btrfs_check_raid_min_devices(fs_info, num_devices - 1);
+ if (ret)
+ return ret;
+
+ device = btrfs_find_device(fs_info->fs_devices, args);
+ if (!device) {
+ if (args->missing)
+ ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
+ else
+ ret = -ENOENT;
+ return ret;
+ }
+
+ if (btrfs_pinned_by_swapfile(fs_info, device)) {
+ btrfs_warn_in_rcu(fs_info,
+ "cannot remove device %s (devid %llu) due to active swapfile",
+ rcu_str_deref(device->name), device->devid);
+ return -ETXTBSY;
+ }
+
+ if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
+ return BTRFS_ERROR_DEV_TGT_REPLACE;
+
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
+ fs_info->fs_devices->rw_devices == 1)
+ return BTRFS_ERROR_DEV_ONLY_WRITABLE;
+
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ mutex_lock(&fs_info->chunk_mutex);
+ list_del_init(&device->dev_alloc_list);
+ device->fs_devices->rw_devices--;
+ mutex_unlock(&fs_info->chunk_mutex);
+ }
+
+ ret = btrfs_shrink_device(device, 0);
+ if (ret)
+ goto error_undo;
+
+ trans = btrfs_start_transaction(fs_info->chunk_root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto error_undo;
+ }
+
+ ret = btrfs_rm_dev_item(trans, device);
+ if (ret) {
+ /* Any error in dev item removal is critical */
+ btrfs_crit(fs_info,
+ "failed to remove device item for devid %llu: %d",
+ device->devid, ret);
+ btrfs_abort_transaction(trans, ret);
+ btrfs_end_transaction(trans);
+ return ret;
+ }
+
+ clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
+ btrfs_scrub_cancel_dev(device);
+
+ /*
+ * the device list mutex makes sure that we don't change
+ * the device list while someone else is writing out all
+ * the device supers. Whoever is writing all supers, should
+ * lock the device list mutex before getting the number of
+ * devices in the super block (super_copy). Conversely,
+ * whoever updates the number of devices in the super block
+ * (super_copy) should hold the device list mutex.
+ */
+
+ /*
+ * In normal cases the cur_devices == fs_devices. But in case
+ * of deleting a seed device, the cur_devices should point to
+ * its own fs_devices listed under the fs_devices->seed_list.
+ */
+ cur_devices = device->fs_devices;
+ mutex_lock(&fs_devices->device_list_mutex);
+ list_del_rcu(&device->dev_list);
+
+ cur_devices->num_devices--;
+ cur_devices->total_devices--;
+ /* Update total_devices of the parent fs_devices if it's seed */
+ if (cur_devices != fs_devices)
+ fs_devices->total_devices--;
+
+ if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
+ cur_devices->missing_devices--;
+
+ btrfs_assign_next_active_device(device, NULL);
+
+ if (device->bdev) {
+ cur_devices->open_devices--;
+ /* remove sysfs entry */
+ btrfs_sysfs_remove_device(device);
+ }
+
+ num_devices = btrfs_super_num_devices(fs_info->super_copy) - 1;
+ btrfs_set_super_num_devices(fs_info->super_copy, num_devices);
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ /*
+ * At this point, the device is zero sized and detached from the
+ * devices list. All that's left is to zero out the old supers and
+ * free the device.
+ *
+ * We cannot call btrfs_close_bdev() here because we're holding the sb
+ * write lock, and blkdev_put() will pull in the ->open_mutex on the
+ * block device and it's dependencies. Instead just flush the device
+ * and let the caller do the final blkdev_put.
+ */
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ btrfs_scratch_superblocks(fs_info, device->bdev,
+ device->name->str);
+ if (device->bdev) {
+ sync_blockdev(device->bdev);
+ invalidate_bdev(device->bdev);
+ }
+ }
+
+ *bdev = device->bdev;
+ *mode = device->mode;
+ synchronize_rcu();
+ btrfs_free_device(device);
+
+ /*
+ * This can happen if cur_devices is the private seed devices list. We
+ * cannot call close_fs_devices() here because it expects the uuid_mutex
+ * to be held, but in fact we don't need that for the private
+ * seed_devices, we can simply decrement cur_devices->opened and then
+ * remove it from our list and free the fs_devices.
+ */
+ if (cur_devices->num_devices == 0) {
+ list_del_init(&cur_devices->seed_list);
+ ASSERT(cur_devices->opened == 1);
+ cur_devices->opened--;
+ free_fs_devices(cur_devices);
+ }
+
+ ret = btrfs_commit_transaction(trans);
+
+ return ret;
+
+error_undo:
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ mutex_lock(&fs_info->chunk_mutex);
+ list_add(&device->dev_alloc_list,
+ &fs_devices->alloc_list);
+ device->fs_devices->rw_devices++;
+ mutex_unlock(&fs_info->chunk_mutex);
+ }
+ return ret;
+}
+
+void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev)
+{
+ struct btrfs_fs_devices *fs_devices;
+
+ lockdep_assert_held(&srcdev->fs_info->fs_devices->device_list_mutex);
+
+ /*
+ * in case of fs with no seed, srcdev->fs_devices will point
+ * to fs_devices of fs_info. However when the dev being replaced is
+ * a seed dev it will point to the seed's local fs_devices. In short
+ * srcdev will have its correct fs_devices in both the cases.
+ */
+ fs_devices = srcdev->fs_devices;
+
+ list_del_rcu(&srcdev->dev_list);
+ list_del(&srcdev->dev_alloc_list);
+ fs_devices->num_devices--;
+ if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state))
+ fs_devices->missing_devices--;
+
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state))
+ fs_devices->rw_devices--;
+
+ if (srcdev->bdev)
+ fs_devices->open_devices--;
+}
+
+void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev)
+{
+ struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
+
+ mutex_lock(&uuid_mutex);
+
+ btrfs_close_bdev(srcdev);
+ synchronize_rcu();
+ btrfs_free_device(srcdev);
+
+ /* if this is no devs we rather delete the fs_devices */
+ if (!fs_devices->num_devices) {
+ /*
+ * On a mounted FS, num_devices can't be zero unless it's a
+ * seed. In case of a seed device being replaced, the replace
+ * target added to the sprout FS, so there will be no more
+ * device left under the seed FS.
+ */
+ ASSERT(fs_devices->seeding);
+
+ list_del_init(&fs_devices->seed_list);
+ close_fs_devices(fs_devices);
+ free_fs_devices(fs_devices);
+ }
+ mutex_unlock(&uuid_mutex);
+}
+
+void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev)
+{
+ struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices;
+
+ mutex_lock(&fs_devices->device_list_mutex);
+
+ btrfs_sysfs_remove_device(tgtdev);
+
+ if (tgtdev->bdev)
+ fs_devices->open_devices--;
+
+ fs_devices->num_devices--;
+
+ btrfs_assign_next_active_device(tgtdev, NULL);
+
+ list_del_rcu(&tgtdev->dev_list);
+
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev->bdev,
+ tgtdev->name->str);
+
+ btrfs_close_bdev(tgtdev);
+ synchronize_rcu();
+ btrfs_free_device(tgtdev);
+}
+
+/**
+ * Populate args from device at path
+ *
+ * @fs_info: the filesystem
+ * @args: the args to populate
+ * @path: the path to the device
+ *
+ * This will read the super block of the device at @path and populate @args with
+ * the devid, fsid, and uuid. This is meant to be used for ioctls that need to
+ * lookup a device to operate on, but need to do it before we take any locks.
+ * This properly handles the special case of "missing" that a user may pass in,
+ * and does some basic sanity checks. The caller must make sure that @path is
+ * properly NUL terminated before calling in, and must call
+ * btrfs_put_dev_args_from_path() in order to free up the temporary fsid and
+ * uuid buffers.
+ *
+ * Return: 0 for success, -errno for failure
+ */
+int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
+ struct btrfs_dev_lookup_args *args,
+ const char *path)
+{
+ struct btrfs_super_block *disk_super;
+ struct block_device *bdev;
+ int ret;
+
+ if (!path || !path[0])
+ return -EINVAL;
+ if (!strcmp(path, "missing")) {
+ args->missing = true;
+ return 0;
+ }
+
+ args->uuid = kzalloc(BTRFS_UUID_SIZE, GFP_KERNEL);
+ args->fsid = kzalloc(BTRFS_FSID_SIZE, GFP_KERNEL);
+ if (!args->uuid || !args->fsid) {
+ btrfs_put_dev_args_from_path(args);
+ return -ENOMEM;
+ }
+
+ ret = btrfs_get_bdev_and_sb(path, FMODE_READ, fs_info->bdev_holder, 0,
+ &bdev, &disk_super);
+ if (ret) {
+ btrfs_put_dev_args_from_path(args);
+ return ret;
+ }
+
+ args->devid = btrfs_stack_device_id(&disk_super->dev_item);
+ memcpy(args->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE);
+ if (btrfs_fs_incompat(fs_info, METADATA_UUID))
+ memcpy(args->fsid, disk_super->metadata_uuid, BTRFS_FSID_SIZE);
+ else
+ memcpy(args->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
+ btrfs_release_disk_super(disk_super);
+ blkdev_put(bdev, FMODE_READ);
+ return 0;
+}
+
+/*
+ * Only use this jointly with btrfs_get_dev_args_from_path() because we will
+ * allocate our ->uuid and ->fsid pointers, everybody else uses local variables
+ * that don't need to be freed.
+ */
+void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args)
+{
+ kfree(args->uuid);
+ kfree(args->fsid);
+ args->uuid = NULL;
+ args->fsid = NULL;
+}
+
+struct btrfs_device *btrfs_find_device_by_devspec(
+ struct btrfs_fs_info *fs_info, u64 devid,
+ const char *device_path)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct btrfs_device *device;
+ int ret;
+
+ if (devid) {
+ args.devid = devid;
+ device = btrfs_find_device(fs_info->fs_devices, &args);
+ if (!device)
+ return ERR_PTR(-ENOENT);
+ return device;
+ }
+
+ ret = btrfs_get_dev_args_from_path(fs_info, &args, device_path);
+ if (ret)
+ return ERR_PTR(ret);
+ device = btrfs_find_device(fs_info->fs_devices, &args);
+ btrfs_put_dev_args_from_path(&args);
+ if (!device)
+ return ERR_PTR(-ENOENT);
+ return device;
+}
+
+static struct btrfs_fs_devices *btrfs_init_sprout(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ struct btrfs_fs_devices *old_devices;
+ struct btrfs_fs_devices *seed_devices;
+
+ lockdep_assert_held(&uuid_mutex);
+ if (!fs_devices->seeding)
+ return ERR_PTR(-EINVAL);
+
+ /*
+ * Private copy of the seed devices, anchored at
+ * fs_info->fs_devices->seed_list
+ */
+ seed_devices = alloc_fs_devices(NULL, NULL);
+ if (IS_ERR(seed_devices))
+ return seed_devices;
+
+ /*
+ * It's necessary to retain a copy of the original seed fs_devices in
+ * fs_uuids so that filesystems which have been seeded can successfully
+ * reference the seed device from open_seed_devices. This also supports
+ * multiple fs seed.
+ */
+ old_devices = clone_fs_devices(fs_devices);
+ if (IS_ERR(old_devices)) {
+ kfree(seed_devices);
+ return old_devices;
+ }
+
+ list_add(&old_devices->fs_list, &fs_uuids);
+
+ memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
+ seed_devices->opened = 1;
+ INIT_LIST_HEAD(&seed_devices->devices);
+ INIT_LIST_HEAD(&seed_devices->alloc_list);
+ mutex_init(&seed_devices->device_list_mutex);
+
+ return seed_devices;
+}
+
+/*
+ * Splice seed devices into the sprout fs_devices.
+ * Generate a new fsid for the sprouted read-write filesystem.
+ */
+static void btrfs_setup_sprout(struct btrfs_fs_info *fs_info,
+ struct btrfs_fs_devices *seed_devices)
+{
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ struct btrfs_super_block *disk_super = fs_info->super_copy;
+ struct btrfs_device *device;
+ u64 super_flags;
+
+ /*
+ * We are updating the fsid, the thread leading to device_list_add()
+ * could race, so uuid_mutex is needed.
+ */
+ lockdep_assert_held(&uuid_mutex);
+
+ /*
+ * The threads listed below may traverse dev_list but can do that without
+ * device_list_mutex:
+ * - All device ops and balance - as we are in btrfs_exclop_start.
+ * - Various dev_list readers - are using RCU.
+ * - btrfs_ioctl_fitrim() - is using RCU.
+ *
+ * For-read threads as below are using device_list_mutex:
+ * - Readonly scrub btrfs_scrub_dev()
+ * - Readonly scrub btrfs_scrub_progress()
+ * - btrfs_get_dev_stats()
+ */
+ lockdep_assert_held(&fs_devices->device_list_mutex);
+
+ list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
+ synchronize_rcu);
+ list_for_each_entry(device, &seed_devices->devices, dev_list)
+ device->fs_devices = seed_devices;
+
+ fs_devices->seeding = false;
+ fs_devices->num_devices = 0;
+ fs_devices->open_devices = 0;
+ fs_devices->missing_devices = 0;
+ fs_devices->rotating = false;
+ list_add(&seed_devices->seed_list, &fs_devices->seed_list);
+
+ generate_random_uuid(fs_devices->fsid);
+ memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE);
+ memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
+
+ super_flags = btrfs_super_flags(disk_super) &
+ ~BTRFS_SUPER_FLAG_SEEDING;
+ btrfs_set_super_flags(disk_super, super_flags);
+}
+
+/*
+ * Store the expected generation for seed devices in device items.
+ */
+static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_root *root = fs_info->chunk_root;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_dev_item *dev_item;
+ struct btrfs_device *device;
+ struct btrfs_key key;
+ u8 fs_uuid[BTRFS_FSID_SIZE];
+ u8 dev_uuid[BTRFS_UUID_SIZE];
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+ key.offset = 0;
+ key.type = BTRFS_DEV_ITEM_KEY;
+
+ while (1) {
+ btrfs_reserve_chunk_metadata(trans, false);
+ ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+ btrfs_trans_release_chunk_metadata(trans);
+ if (ret < 0)
+ goto error;
+
+ leaf = path->nodes[0];
+next_slot:
+ if (path->slots[0] >= btrfs_header_nritems(leaf)) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret > 0)
+ break;
+ if (ret < 0)
+ goto error;
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+ btrfs_release_path(path);
+ continue;
+ }
+
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+ if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
+ key.type != BTRFS_DEV_ITEM_KEY)
+ break;
+
+ dev_item = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_dev_item);
+ args.devid = btrfs_device_id(leaf, dev_item);
+ read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
+ BTRFS_UUID_SIZE);
+ read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
+ BTRFS_FSID_SIZE);
+ args.uuid = dev_uuid;
+ args.fsid = fs_uuid;
+ device = btrfs_find_device(fs_info->fs_devices, &args);
+ BUG_ON(!device); /* Logic error */
+
+ if (device->fs_devices->seeding) {
+ btrfs_set_device_generation(leaf, dev_item,
+ device->generation);
+ btrfs_mark_buffer_dirty(leaf);
+ }
+
+ path->slots[0]++;
+ goto next_slot;
+ }
+ ret = 0;
+error:
+ btrfs_free_path(path);
+ return ret;
+}
+
+int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path)
+{
+ struct btrfs_root *root = fs_info->dev_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_device *device;
+ struct block_device *bdev;
+ struct super_block *sb = fs_info->sb;
+ struct rcu_string *name;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ struct btrfs_fs_devices *seed_devices = NULL;
+ u64 orig_super_total_bytes;
+ u64 orig_super_num_devices;
+ int ret = 0;
+ bool seeding_dev = false;
+ bool locked = false;
+
+ if (sb_rdonly(sb) && !fs_devices->seeding)
+ return -EROFS;
+
+ bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
+ fs_info->bdev_holder);
+ if (IS_ERR(bdev))
+ return PTR_ERR(bdev);
+
+ if (!btrfs_check_device_zone_type(fs_info, bdev)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ if (fs_devices->seeding) {
+ seeding_dev = true;
+ down_write(&sb->s_umount);
+ mutex_lock(&uuid_mutex);
+ locked = true;
+ }
+
+ sync_blockdev(bdev);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
+ if (device->bdev == bdev) {
+ ret = -EEXIST;
+ rcu_read_unlock();
+ goto error;
+ }
+ }
+ rcu_read_unlock();
+
+ device = btrfs_alloc_device(fs_info, NULL, NULL);
+ if (IS_ERR(device)) {
+ /* we can safely leave the fs_devices entry around */
+ ret = PTR_ERR(device);
+ goto error;
+ }
+
+ name = rcu_string_strdup(device_path, GFP_KERNEL);
+ if (!name) {
+ ret = -ENOMEM;
+ goto error_free_device;
+ }
+ rcu_assign_pointer(device->name, name);
+
+ device->fs_info = fs_info;
+ device->bdev = bdev;
+ ret = lookup_bdev(device_path, &device->devt);
+ if (ret)
+ goto error_free_device;
+
+ ret = btrfs_get_dev_zone_info(device, false);
+ if (ret)
+ goto error_free_device;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto error_free_zone;
+ }
+
+ set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
+ device->generation = trans->transid;
+ device->io_width = fs_info->sectorsize;
+ device->io_align = fs_info->sectorsize;
+ device->sector_size = fs_info->sectorsize;
+ device->total_bytes =
+ round_down(bdev_nr_bytes(bdev), fs_info->sectorsize);
+ device->disk_total_bytes = device->total_bytes;
+ device->commit_total_bytes = device->total_bytes;
+ set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
+ clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
+ device->mode = FMODE_EXCL;
+ device->dev_stats_valid = 1;
+ set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE);
+
+ if (seeding_dev) {
+ btrfs_clear_sb_rdonly(sb);
+
+ /* GFP_KERNEL allocation must not be under device_list_mutex */
+ seed_devices = btrfs_init_sprout(fs_info);
+ if (IS_ERR(seed_devices)) {
+ ret = PTR_ERR(seed_devices);
+ btrfs_abort_transaction(trans, ret);
+ goto error_trans;
+ }
+ }
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ if (seeding_dev) {
+ btrfs_setup_sprout(fs_info, seed_devices);
+ btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev,
+ device);
+ }
+
+ device->fs_devices = fs_devices;
+
+ mutex_lock(&fs_info->chunk_mutex);
+ list_add_rcu(&device->dev_list, &fs_devices->devices);
+ list_add(&device->dev_alloc_list, &fs_devices->alloc_list);
+ fs_devices->num_devices++;
+ fs_devices->open_devices++;
+ fs_devices->rw_devices++;
+ fs_devices->total_devices++;
+ fs_devices->total_rw_bytes += device->total_bytes;
+
+ atomic64_add(device->total_bytes, &fs_info->free_chunk_space);
+
+ if (!bdev_nonrot(bdev))
+ fs_devices->rotating = true;
+
+ orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
+ btrfs_set_super_total_bytes(fs_info->super_copy,
+ round_down(orig_super_total_bytes + device->total_bytes,
+ fs_info->sectorsize));
+
+ orig_super_num_devices = btrfs_super_num_devices(fs_info->super_copy);
+ btrfs_set_super_num_devices(fs_info->super_copy,
+ orig_super_num_devices + 1);
+
+ /*
+ * we've got more storage, clear any full flags on the space
+ * infos
+ */
+ btrfs_clear_space_info_full(fs_info);
+
+ mutex_unlock(&fs_info->chunk_mutex);
+
+ /* Add sysfs device entry */
+ btrfs_sysfs_add_device(device);
+
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ if (seeding_dev) {
+ mutex_lock(&fs_info->chunk_mutex);
+ ret = init_first_rw_device(trans);
+ mutex_unlock(&fs_info->chunk_mutex);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto error_sysfs;
+ }
+ }
+
+ ret = btrfs_add_dev_item(trans, device);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto error_sysfs;
+ }
+
+ if (seeding_dev) {
+ ret = btrfs_finish_sprout(trans);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto error_sysfs;
+ }
+
+ /*
+ * fs_devices now represents the newly sprouted filesystem and
+ * its fsid has been changed by btrfs_sprout_splice().
+ */
+ btrfs_sysfs_update_sprout_fsid(fs_devices);
+ }
+
+ ret = btrfs_commit_transaction(trans);
+
+ if (seeding_dev) {
+ mutex_unlock(&uuid_mutex);
+ up_write(&sb->s_umount);
+ locked = false;
+
+ if (ret) /* transaction commit */
+ return ret;
+
+ ret = btrfs_relocate_sys_chunks(fs_info);
+ if (ret < 0)
+ btrfs_handle_fs_error(fs_info, ret,
+ "Failed to relocate sys chunks after device initialization. This can be fixed using the \"btrfs balance\" command.");
+ trans = btrfs_attach_transaction(root);
+ if (IS_ERR(trans)) {
+ if (PTR_ERR(trans) == -ENOENT)
+ return 0;
+ ret = PTR_ERR(trans);
+ trans = NULL;
+ goto error_sysfs;
+ }
+ ret = btrfs_commit_transaction(trans);
+ }
+
+ /*
+ * Now that we have written a new super block to this device, check all
+ * other fs_devices list if device_path alienates any other scanned
+ * device.
+ * We can ignore the return value as it typically returns -EINVAL and
+ * only succeeds if the device was an alien.
+ */
+ btrfs_forget_devices(device->devt);
+
+ /* Update ctime/mtime for blkid or udev */
+ update_dev_time(device_path);
+
+ return ret;
+
+error_sysfs:
+ btrfs_sysfs_remove_device(device);
+ mutex_lock(&fs_info->fs_devices->device_list_mutex);
+ mutex_lock(&fs_info->chunk_mutex);
+ list_del_rcu(&device->dev_list);
+ list_del(&device->dev_alloc_list);
+ fs_info->fs_devices->num_devices--;
+ fs_info->fs_devices->open_devices--;
+ fs_info->fs_devices->rw_devices--;
+ fs_info->fs_devices->total_devices--;
+ fs_info->fs_devices->total_rw_bytes -= device->total_bytes;
+ atomic64_sub(device->total_bytes, &fs_info->free_chunk_space);
+ btrfs_set_super_total_bytes(fs_info->super_copy,
+ orig_super_total_bytes);
+ btrfs_set_super_num_devices(fs_info->super_copy,
+ orig_super_num_devices);
+ mutex_unlock(&fs_info->chunk_mutex);
+ mutex_unlock(&fs_info->fs_devices->device_list_mutex);
+error_trans:
+ if (seeding_dev)
+ btrfs_set_sb_rdonly(sb);
+ if (trans)
+ btrfs_end_transaction(trans);
+error_free_zone:
+ btrfs_destroy_dev_zone_info(device);
+error_free_device:
+ btrfs_free_device(device);
+error:
+ blkdev_put(bdev, FMODE_EXCL);
+ if (locked) {
+ mutex_unlock(&uuid_mutex);
+ up_write(&sb->s_umount);
+ }
+ return ret;
+}
+
+static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
+ struct btrfs_device *device)
+{
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_root *root = device->fs_info->chunk_root;
+ struct btrfs_dev_item *dev_item;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+ key.type = BTRFS_DEV_ITEM_KEY;
+ key.offset = device->devid;
+
+ ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+ if (ret < 0)
+ goto out;
+
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ leaf = path->nodes[0];
+ dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
+
+ btrfs_set_device_id(leaf, dev_item, device->devid);
+ btrfs_set_device_type(leaf, dev_item, device->type);
+ btrfs_set_device_io_align(leaf, dev_item, device->io_align);
+ btrfs_set_device_io_width(leaf, dev_item, device->io_width);
+ btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
+ btrfs_set_device_total_bytes(leaf, dev_item,
+ btrfs_device_get_disk_total_bytes(device));
+ btrfs_set_device_bytes_used(leaf, dev_item,
+ btrfs_device_get_bytes_used(device));
+ btrfs_mark_buffer_dirty(leaf);
+
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+int btrfs_grow_device(struct btrfs_trans_handle *trans,
+ struct btrfs_device *device, u64 new_size)
+{
+ struct btrfs_fs_info *fs_info = device->fs_info;
+ struct btrfs_super_block *super_copy = fs_info->super_copy;
+ u64 old_total;
+ u64 diff;
+ int ret;
+
+ if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
+ return -EACCES;
+
+ new_size = round_down(new_size, fs_info->sectorsize);
+
+ mutex_lock(&fs_info->chunk_mutex);
+ old_total = btrfs_super_total_bytes(super_copy);
+ diff = round_down(new_size - device->total_bytes, fs_info->sectorsize);
+
+ if (new_size <= device->total_bytes ||
+ test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
+ mutex_unlock(&fs_info->chunk_mutex);
+ return -EINVAL;
+ }
+
+ btrfs_set_super_total_bytes(super_copy,
+ round_down(old_total + diff, fs_info->sectorsize));
+ device->fs_devices->total_rw_bytes += diff;
+
+ btrfs_device_set_total_bytes(device, new_size);
+ btrfs_device_set_disk_total_bytes(device, new_size);
+ btrfs_clear_space_info_full(device->fs_info);
+ if (list_empty(&device->post_commit_list))
+ list_add_tail(&device->post_commit_list,
+ &trans->transaction->dev_update_list);
+ mutex_unlock(&fs_info->chunk_mutex);
+
+ btrfs_reserve_chunk_metadata(trans, false);
+ ret = btrfs_update_device(trans, device);
+ btrfs_trans_release_chunk_metadata(trans);
+
+ return ret;
+}
+
+static int btrfs_free_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_root *root = fs_info->chunk_root;
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
+ key.offset = chunk_offset;
+ key.type = BTRFS_CHUNK_ITEM_KEY;
+
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret < 0)
+ goto out;
+ else if (ret > 0) { /* Logic error or corruption */
+ btrfs_handle_fs_error(fs_info, -ENOENT,
+ "Failed lookup while freeing chunk.");
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = btrfs_del_item(trans, root, path);
+ if (ret < 0)
+ btrfs_handle_fs_error(fs_info, ret,
+ "Failed to delete chunk item.");
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
+{
+ struct btrfs_super_block *super_copy = fs_info->super_copy;
+ struct btrfs_disk_key *disk_key;
+ struct btrfs_chunk *chunk;
+ u8 *ptr;
+ int ret = 0;
+ u32 num_stripes;
+ u32 array_size;
+ u32 len = 0;
+ u32 cur;
+ struct btrfs_key key;
+
+ lockdep_assert_held(&fs_info->chunk_mutex);
+ array_size = btrfs_super_sys_array_size(super_copy);
+
+ ptr = super_copy->sys_chunk_array;
+ cur = 0;
+
+ while (cur < array_size) {
+ disk_key = (struct btrfs_disk_key *)ptr;
+ btrfs_disk_key_to_cpu(&key, disk_key);
+
+ len = sizeof(*disk_key);
+
+ if (key.type == BTRFS_CHUNK_ITEM_KEY) {
+ chunk = (struct btrfs_chunk *)(ptr + len);
+ num_stripes = btrfs_stack_chunk_num_stripes(chunk);
+ len += btrfs_chunk_item_size(num_stripes);
+ } else {
+ ret = -EIO;
+ break;
+ }
+ if (key.objectid == BTRFS_FIRST_CHUNK_TREE_OBJECTID &&
+ key.offset == chunk_offset) {
+ memmove(ptr, ptr + len, array_size - (cur + len));
+ array_size -= len;
+ btrfs_set_super_sys_array_size(super_copy, array_size);
+ } else {
+ ptr += len;
+ cur += len;
+ }
+ }
+ return ret;
+}
+
+/*
+ * btrfs_get_chunk_map() - Find the mapping containing the given logical extent.
+ * @logical: Logical block offset in bytes.
+ * @length: Length of extent in bytes.
+ *
+ * Return: Chunk mapping or ERR_PTR.
+ */
+struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 length)
+{
+ struct extent_map_tree *em_tree;
+ struct extent_map *em;
+
+ em_tree = &fs_info->mapping_tree;
+ read_lock(&em_tree->lock);
+ em = lookup_extent_mapping(em_tree, logical, length);
+ read_unlock(&em_tree->lock);
+
+ if (!em) {
+ btrfs_crit(fs_info,
+ "unable to find chunk map for logical %llu length %llu",
+ logical, length);
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (em->start > logical || em->start + em->len <= logical) {
+ btrfs_crit(fs_info,
+ "found a bad chunk map, wanted %llu-%llu, found %llu-%llu",
+ logical, logical + length, em->start, em->start + em->len);
+ free_extent_map(em);
+ return ERR_PTR(-EINVAL);
+ }
+
+ /* callers are responsible for dropping em's ref. */
+ return em;
+}
+
+static int remove_chunk_item(struct btrfs_trans_handle *trans,
+ struct map_lookup *map, u64 chunk_offset)
+{
+ int i;
+
+ /*
+ * Removing chunk items and updating the device items in the chunks btree
+ * requires holding the chunk_mutex.
+ * See the comment at btrfs_chunk_alloc() for the details.
+ */
+ lockdep_assert_held(&trans->fs_info->chunk_mutex);
+
+ for (i = 0; i < map->num_stripes; i++) {
+ int ret;
+
+ ret = btrfs_update_device(trans, map->stripes[i].dev);
+ if (ret)
+ return ret;
+ }
+
+ return btrfs_free_chunk(trans, chunk_offset);
+}
+
+int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct extent_map *em;
+ struct map_lookup *map;
+ u64 dev_extent_len = 0;
+ int i, ret = 0;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+
+ em = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
+ if (IS_ERR(em)) {
+ /*
+ * This is a logic error, but we don't want to just rely on the
+ * user having built with ASSERT enabled, so if ASSERT doesn't
+ * do anything we still error out.
+ */
+ ASSERT(0);
+ return PTR_ERR(em);
+ }
+ map = em->map_lookup;
+
+ /*
+ * First delete the device extent items from the devices btree.
+ * We take the device_list_mutex to avoid racing with the finishing phase
+ * of a device replace operation. See the comment below before acquiring
+ * fs_info->chunk_mutex. Note that here we do not acquire the chunk_mutex
+ * because that can result in a deadlock when deleting the device extent
+ * items from the devices btree - COWing an extent buffer from the btree
+ * may result in allocating a new metadata chunk, which would attempt to
+ * lock again fs_info->chunk_mutex.
+ */
+ mutex_lock(&fs_devices->device_list_mutex);
+ for (i = 0; i < map->num_stripes; i++) {
+ struct btrfs_device *device = map->stripes[i].dev;
+ ret = btrfs_free_dev_extent(trans, device,
+ map->stripes[i].physical,
+ &dev_extent_len);
+ if (ret) {
+ mutex_unlock(&fs_devices->device_list_mutex);
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ if (device->bytes_used > 0) {
+ mutex_lock(&fs_info->chunk_mutex);
+ btrfs_device_set_bytes_used(device,
+ device->bytes_used - dev_extent_len);
+ atomic64_add(dev_extent_len, &fs_info->free_chunk_space);
+ btrfs_clear_space_info_full(fs_info);
+ mutex_unlock(&fs_info->chunk_mutex);
+ }
+ }
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ /*
+ * We acquire fs_info->chunk_mutex for 2 reasons:
+ *
+ * 1) Just like with the first phase of the chunk allocation, we must
+ * reserve system space, do all chunk btree updates and deletions, and
+ * update the system chunk array in the superblock while holding this
+ * mutex. This is for similar reasons as explained on the comment at
+ * the top of btrfs_chunk_alloc();
+ *
+ * 2) Prevent races with the final phase of a device replace operation
+ * that replaces the device object associated with the map's stripes,
+ * because the device object's id can change at any time during that
+ * final phase of the device replace operation
+ * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
+ * replaced device and then see it with an ID of
+ * BTRFS_DEV_REPLACE_DEVID, which would cause a failure when updating
+ * the device item, which does not exists on the chunk btree.
+ * The finishing phase of device replace acquires both the
+ * device_list_mutex and the chunk_mutex, in that order, so we are
+ * safe by just acquiring the chunk_mutex.
+ */
+ trans->removing_chunk = true;
+ mutex_lock(&fs_info->chunk_mutex);
+
+ check_system_chunk(trans, map->type);
+
+ ret = remove_chunk_item(trans, map, chunk_offset);
+ /*
+ * Normally we should not get -ENOSPC since we reserved space before
+ * through the call to check_system_chunk().
+ *
+ * Despite our system space_info having enough free space, we may not
+ * be able to allocate extents from its block groups, because all have
+ * an incompatible profile, which will force us to allocate a new system
+ * block group with the right profile, or right after we called
+ * check_system_space() above, a scrub turned the only system block group
+ * with enough free space into RO mode.
+ * This is explained with more detail at do_chunk_alloc().
+ *
+ * So if we get -ENOSPC, allocate a new system chunk and retry once.
+ */
+ if (ret == -ENOSPC) {
+ const u64 sys_flags = btrfs_system_alloc_profile(fs_info);
+ struct btrfs_block_group *sys_bg;
+
+ sys_bg = btrfs_create_chunk(trans, sys_flags);
+ if (IS_ERR(sys_bg)) {
+ ret = PTR_ERR(sys_bg);
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ ret = btrfs_chunk_alloc_add_chunk_item(trans, sys_bg);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ ret = remove_chunk_item(trans, map, chunk_offset);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+ } else if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ trace_btrfs_chunk_free(fs_info, map, chunk_offset, em->len);
+
+ if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
+ ret = btrfs_del_sys_chunk(fs_info, chunk_offset);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+ }
+
+ mutex_unlock(&fs_info->chunk_mutex);
+ trans->removing_chunk = false;
+
+ /*
+ * We are done with chunk btree updates and deletions, so release the
+ * system space we previously reserved (with check_system_chunk()).
+ */
+ btrfs_trans_release_chunk_metadata(trans);
+
+ ret = btrfs_remove_block_group(trans, chunk_offset, em);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+out:
+ if (trans->removing_chunk) {
+ mutex_unlock(&fs_info->chunk_mutex);
+ trans->removing_chunk = false;
+ }
+ /* once for us */
+ free_extent_map(em);
+ return ret;
+}
+
+int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
+{
+ struct btrfs_root *root = fs_info->chunk_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_block_group *block_group;
+ u64 length;
+ int ret;
+
+ if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
+ btrfs_err(fs_info,
+ "relocate: not supported on extent tree v2 yet");
+ return -EINVAL;
+ }
+
+ /*
+ * Prevent races with automatic removal of unused block groups.
+ * After we relocate and before we remove the chunk with offset
+ * chunk_offset, automatic removal of the block group can kick in,
+ * resulting in a failure when calling btrfs_remove_chunk() below.
+ *
+ * Make sure to acquire this mutex before doing a tree search (dev
+ * or chunk trees) to find chunks. Otherwise the cleaner kthread might
+ * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
+ * we release the path used to search the chunk/dev tree and before
+ * the current task acquires this mutex and calls us.
+ */
+ lockdep_assert_held(&fs_info->reclaim_bgs_lock);
+
+ /* step one, relocate all the extents inside this chunk */
+ btrfs_scrub_pause(fs_info);
+ ret = btrfs_relocate_block_group(fs_info, chunk_offset);
+ btrfs_scrub_continue(fs_info);
+ if (ret) {
+ /*
+ * If we had a transaction abort, stop all running scrubs.
+ * See transaction.c:cleanup_transaction() why we do it here.
+ */
+ if (BTRFS_FS_ERROR(fs_info))
+ btrfs_scrub_cancel(fs_info);
+ return ret;
+ }
+
+ block_group = btrfs_lookup_block_group(fs_info, chunk_offset);
+ if (!block_group)
+ return -ENOENT;
+ btrfs_discard_cancel_work(&fs_info->discard_ctl, block_group);
+ length = block_group->length;
+ btrfs_put_block_group(block_group);
+
+ /*
+ * On a zoned file system, discard the whole block group, this will
+ * trigger a REQ_OP_ZONE_RESET operation on the device zone. If
+ * resetting the zone fails, don't treat it as a fatal problem from the
+ * filesystem's point of view.
+ */
+ if (btrfs_is_zoned(fs_info)) {
+ ret = btrfs_discard_extent(fs_info, chunk_offset, length, NULL);
+ if (ret)
+ btrfs_info(fs_info,
+ "failed to reset zone %llu after relocation",
+ chunk_offset);
+ }
+
+ trans = btrfs_start_trans_remove_block_group(root->fs_info,
+ chunk_offset);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ btrfs_handle_fs_error(root->fs_info, ret, NULL);
+ return ret;
+ }
+
+ /*
+ * step two, delete the device extents and the
+ * chunk tree entries
+ */
+ ret = btrfs_remove_chunk(trans, chunk_offset);
+ btrfs_end_transaction(trans);
+ return ret;
+}
+
+static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *chunk_root = fs_info->chunk_root;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_chunk *chunk;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ u64 chunk_type;
+ bool retried = false;
+ int failed = 0;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+again:
+ key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
+ key.offset = (u64)-1;
+ key.type = BTRFS_CHUNK_ITEM_KEY;
+
+ while (1) {
+ mutex_lock(&fs_info->reclaim_bgs_lock);
+ ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
+ if (ret < 0) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ goto error;
+ }
+ BUG_ON(ret == 0); /* Corruption */
+
+ ret = btrfs_previous_item(chunk_root, path, key.objectid,
+ key.type);
+ if (ret)
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ if (ret < 0)
+ goto error;
+ if (ret > 0)
+ break;
+
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+
+ chunk = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_chunk);
+ chunk_type = btrfs_chunk_type(leaf, chunk);
+ btrfs_release_path(path);
+
+ if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
+ ret = btrfs_relocate_chunk(fs_info, found_key.offset);
+ if (ret == -ENOSPC)
+ failed++;
+ else
+ BUG_ON(ret);
+ }
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+
+ if (found_key.offset == 0)
+ break;
+ key.offset = found_key.offset - 1;
+ }
+ ret = 0;
+ if (failed && !retried) {
+ failed = 0;
+ retried = true;
+ goto again;
+ } else if (WARN_ON(failed && retried)) {
+ ret = -ENOSPC;
+ }
+error:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * return 1 : allocate a data chunk successfully,
+ * return <0: errors during allocating a data chunk,
+ * return 0 : no need to allocate a data chunk.
+ */
+static int btrfs_may_alloc_data_chunk(struct btrfs_fs_info *fs_info,
+ u64 chunk_offset)
+{
+ struct btrfs_block_group *cache;
+ u64 bytes_used;
+ u64 chunk_type;
+
+ cache = btrfs_lookup_block_group(fs_info, chunk_offset);
+ ASSERT(cache);
+ chunk_type = cache->flags;
+ btrfs_put_block_group(cache);
+
+ if (!(chunk_type & BTRFS_BLOCK_GROUP_DATA))
+ return 0;
+
+ spin_lock(&fs_info->data_sinfo->lock);
+ bytes_used = fs_info->data_sinfo->bytes_used;
+ spin_unlock(&fs_info->data_sinfo->lock);
+
+ if (!bytes_used) {
+ struct btrfs_trans_handle *trans;
+ int ret;
+
+ trans = btrfs_join_transaction(fs_info->tree_root);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
+ ret = btrfs_force_chunk_alloc(trans, BTRFS_BLOCK_GROUP_DATA);
+ btrfs_end_transaction(trans);
+ if (ret < 0)
+ return ret;
+ return 1;
+ }
+
+ return 0;
+}
+
+static int insert_balance_item(struct btrfs_fs_info *fs_info,
+ struct btrfs_balance_control *bctl)
+{
+ struct btrfs_root *root = fs_info->tree_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_balance_item *item;
+ struct btrfs_disk_balance_args disk_bargs;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+ int ret, err;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ btrfs_free_path(path);
+ return PTR_ERR(trans);
+ }
+
+ key.objectid = BTRFS_BALANCE_OBJECTID;
+ key.type = BTRFS_TEMPORARY_ITEM_KEY;
+ key.offset = 0;
+
+ ret = btrfs_insert_empty_item(trans, root, path, &key,
+ sizeof(*item));
+ if (ret)
+ goto out;
+
+ leaf = path->nodes[0];
+ item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
+
+ memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item));
+
+ btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
+ btrfs_set_balance_data(leaf, item, &disk_bargs);
+ btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
+ btrfs_set_balance_meta(leaf, item, &disk_bargs);
+ btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
+ btrfs_set_balance_sys(leaf, item, &disk_bargs);
+
+ btrfs_set_balance_flags(leaf, item, bctl->flags);
+
+ btrfs_mark_buffer_dirty(leaf);
+out:
+ btrfs_free_path(path);
+ err = btrfs_commit_transaction(trans);
+ if (err && !ret)
+ ret = err;
+ return ret;
+}
+
+static int del_balance_item(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *root = fs_info->tree_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ int ret, err;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ trans = btrfs_start_transaction_fallback_global_rsv(root, 0);
+ if (IS_ERR(trans)) {
+ btrfs_free_path(path);
+ return PTR_ERR(trans);
+ }
+
+ key.objectid = BTRFS_BALANCE_OBJECTID;
+ key.type = BTRFS_TEMPORARY_ITEM_KEY;
+ key.offset = 0;
+
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = btrfs_del_item(trans, root, path);
+out:
+ btrfs_free_path(path);
+ err = btrfs_commit_transaction(trans);
+ if (err && !ret)
+ ret = err;
+ return ret;
+}
+
+/*
+ * This is a heuristic used to reduce the number of chunks balanced on
+ * resume after balance was interrupted.
+ */
+static void update_balance_args(struct btrfs_balance_control *bctl)
+{
+ /*
+ * Turn on soft mode for chunk types that were being converted.
+ */
+ if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
+ bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
+ if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
+ bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
+ if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
+ bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
+
+ /*
+ * Turn on usage filter if is not already used. The idea is
+ * that chunks that we have already balanced should be
+ * reasonably full. Don't do it for chunks that are being
+ * converted - that will keep us from relocating unconverted
+ * (albeit full) chunks.
+ */
+ if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
+ !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
+ !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
+ bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
+ bctl->data.usage = 90;
+ }
+ if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
+ !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
+ !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
+ bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
+ bctl->sys.usage = 90;
+ }
+ if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
+ !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
+ !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
+ bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
+ bctl->meta.usage = 90;
+ }
+}
+
+/*
+ * Clear the balance status in fs_info and delete the balance item from disk.
+ */
+static void reset_balance_state(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_balance_control *bctl = fs_info->balance_ctl;
+ int ret;
+
+ BUG_ON(!fs_info->balance_ctl);
+
+ spin_lock(&fs_info->balance_lock);
+ fs_info->balance_ctl = NULL;
+ spin_unlock(&fs_info->balance_lock);
+
+ kfree(bctl);
+ ret = del_balance_item(fs_info);
+ if (ret)
+ btrfs_handle_fs_error(fs_info, ret, NULL);
+}
+
+/*
+ * Balance filters. Return 1 if chunk should be filtered out
+ * (should not be balanced).
+ */
+static int chunk_profiles_filter(u64 chunk_type,
+ struct btrfs_balance_args *bargs)
+{
+ chunk_type = chunk_to_extended(chunk_type) &
+ BTRFS_EXTENDED_PROFILE_MASK;
+
+ if (bargs->profiles & chunk_type)
+ return 0;
+
+ return 1;
+}
+
+static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
+ struct btrfs_balance_args *bargs)
+{
+ struct btrfs_block_group *cache;
+ u64 chunk_used;
+ u64 user_thresh_min;
+ u64 user_thresh_max;
+ int ret = 1;
+
+ cache = btrfs_lookup_block_group(fs_info, chunk_offset);
+ chunk_used = cache->used;
+
+ if (bargs->usage_min == 0)
+ user_thresh_min = 0;
+ else
+ user_thresh_min = div_factor_fine(cache->length,
+ bargs->usage_min);
+
+ if (bargs->usage_max == 0)
+ user_thresh_max = 1;
+ else if (bargs->usage_max > 100)
+ user_thresh_max = cache->length;
+ else
+ user_thresh_max = div_factor_fine(cache->length,
+ bargs->usage_max);
+
+ if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max)
+ ret = 0;
+
+ btrfs_put_block_group(cache);
+ return ret;
+}
+
+static int chunk_usage_filter(struct btrfs_fs_info *fs_info,
+ u64 chunk_offset, struct btrfs_balance_args *bargs)
+{
+ struct btrfs_block_group *cache;
+ u64 chunk_used, user_thresh;
+ int ret = 1;
+
+ cache = btrfs_lookup_block_group(fs_info, chunk_offset);
+ chunk_used = cache->used;
+
+ if (bargs->usage_min == 0)
+ user_thresh = 1;
+ else if (bargs->usage > 100)
+ user_thresh = cache->length;
+ else
+ user_thresh = div_factor_fine(cache->length, bargs->usage);
+
+ if (chunk_used < user_thresh)
+ ret = 0;
+
+ btrfs_put_block_group(cache);
+ return ret;
+}
+
+static int chunk_devid_filter(struct extent_buffer *leaf,
+ struct btrfs_chunk *chunk,
+ struct btrfs_balance_args *bargs)
+{
+ struct btrfs_stripe *stripe;
+ int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
+ int i;
+
+ for (i = 0; i < num_stripes; i++) {
+ stripe = btrfs_stripe_nr(chunk, i);
+ if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
+ return 0;
+ }
+
+ return 1;
+}
+
+static u64 calc_data_stripes(u64 type, int num_stripes)
+{
+ const int index = btrfs_bg_flags_to_raid_index(type);
+ const int ncopies = btrfs_raid_array[index].ncopies;
+ const int nparity = btrfs_raid_array[index].nparity;
+
+ return (num_stripes - nparity) / ncopies;
+}
+
+/* [pstart, pend) */
+static int chunk_drange_filter(struct extent_buffer *leaf,
+ struct btrfs_chunk *chunk,
+ struct btrfs_balance_args *bargs)
+{
+ struct btrfs_stripe *stripe;
+ int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
+ u64 stripe_offset;
+ u64 stripe_length;
+ u64 type;
+ int factor;
+ int i;
+
+ if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
+ return 0;
+
+ type = btrfs_chunk_type(leaf, chunk);
+ factor = calc_data_stripes(type, num_stripes);
+
+ for (i = 0; i < num_stripes; i++) {
+ stripe = btrfs_stripe_nr(chunk, i);
+ if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
+ continue;
+
+ stripe_offset = btrfs_stripe_offset(leaf, stripe);
+ stripe_length = btrfs_chunk_length(leaf, chunk);
+ stripe_length = div_u64(stripe_length, factor);
+
+ if (stripe_offset < bargs->pend &&
+ stripe_offset + stripe_length > bargs->pstart)
+ return 0;
+ }
+
+ return 1;
+}
+
+/* [vstart, vend) */
+static int chunk_vrange_filter(struct extent_buffer *leaf,
+ struct btrfs_chunk *chunk,
+ u64 chunk_offset,
+ struct btrfs_balance_args *bargs)
+{
+ if (chunk_offset < bargs->vend &&
+ chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
+ /* at least part of the chunk is inside this vrange */
+ return 0;
+
+ return 1;
+}
+
+static int chunk_stripes_range_filter(struct extent_buffer *leaf,
+ struct btrfs_chunk *chunk,
+ struct btrfs_balance_args *bargs)
+{
+ int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
+
+ if (bargs->stripes_min <= num_stripes
+ && num_stripes <= bargs->stripes_max)
+ return 0;
+
+ return 1;
+}
+
+static int chunk_soft_convert_filter(u64 chunk_type,
+ struct btrfs_balance_args *bargs)
+{
+ if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
+ return 0;
+
+ chunk_type = chunk_to_extended(chunk_type) &
+ BTRFS_EXTENDED_PROFILE_MASK;
+
+ if (bargs->target == chunk_type)
+ return 1;
+
+ return 0;
+}
+
+static int should_balance_chunk(struct extent_buffer *leaf,
+ struct btrfs_chunk *chunk, u64 chunk_offset)
+{
+ struct btrfs_fs_info *fs_info = leaf->fs_info;
+ struct btrfs_balance_control *bctl = fs_info->balance_ctl;
+ struct btrfs_balance_args *bargs = NULL;
+ u64 chunk_type = btrfs_chunk_type(leaf, chunk);
+
+ /* type filter */
+ if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
+ (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
+ return 0;
+ }
+
+ if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
+ bargs = &bctl->data;
+ else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
+ bargs = &bctl->sys;
+ else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
+ bargs = &bctl->meta;
+
+ /* profiles filter */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
+ chunk_profiles_filter(chunk_type, bargs)) {
+ return 0;
+ }
+
+ /* usage filter */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
+ chunk_usage_filter(fs_info, chunk_offset, bargs)) {
+ return 0;
+ } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
+ chunk_usage_range_filter(fs_info, chunk_offset, bargs)) {
+ return 0;
+ }
+
+ /* devid filter */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
+ chunk_devid_filter(leaf, chunk, bargs)) {
+ return 0;
+ }
+
+ /* drange filter, makes sense only with devid filter */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
+ chunk_drange_filter(leaf, chunk, bargs)) {
+ return 0;
+ }
+
+ /* vrange filter */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
+ chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
+ return 0;
+ }
+
+ /* stripes filter */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) &&
+ chunk_stripes_range_filter(leaf, chunk, bargs)) {
+ return 0;
+ }
+
+ /* soft profile changing mode */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
+ chunk_soft_convert_filter(chunk_type, bargs)) {
+ return 0;
+ }
+
+ /*
+ * limited by count, must be the last filter
+ */
+ if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
+ if (bargs->limit == 0)
+ return 0;
+ else
+ bargs->limit--;
+ } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
+ /*
+ * Same logic as the 'limit' filter; the minimum cannot be
+ * determined here because we do not have the global information
+ * about the count of all chunks that satisfy the filters.
+ */
+ if (bargs->limit_max == 0)
+ return 0;
+ else
+ bargs->limit_max--;
+ }
+
+ return 1;
+}
+
+static int __btrfs_balance(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_balance_control *bctl = fs_info->balance_ctl;
+ struct btrfs_root *chunk_root = fs_info->chunk_root;
+ u64 chunk_type;
+ struct btrfs_chunk *chunk;
+ struct btrfs_path *path = NULL;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ struct extent_buffer *leaf;
+ int slot;
+ int ret;
+ int enospc_errors = 0;
+ bool counting = true;
+ /* The single value limit and min/max limits use the same bytes in the */
+ u64 limit_data = bctl->data.limit;
+ u64 limit_meta = bctl->meta.limit;
+ u64 limit_sys = bctl->sys.limit;
+ u32 count_data = 0;
+ u32 count_meta = 0;
+ u32 count_sys = 0;
+ int chunk_reserved = 0;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ /* zero out stat counters */
+ spin_lock(&fs_info->balance_lock);
+ memset(&bctl->stat, 0, sizeof(bctl->stat));
+ spin_unlock(&fs_info->balance_lock);
+again:
+ if (!counting) {
+ /*
+ * The single value limit and min/max limits use the same bytes
+ * in the
+ */
+ bctl->data.limit = limit_data;
+ bctl->meta.limit = limit_meta;
+ bctl->sys.limit = limit_sys;
+ }
+ key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
+ key.offset = (u64)-1;
+ key.type = BTRFS_CHUNK_ITEM_KEY;
+
+ while (1) {
+ if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
+ atomic_read(&fs_info->balance_cancel_req)) {
+ ret = -ECANCELED;
+ goto error;
+ }
+
+ mutex_lock(&fs_info->reclaim_bgs_lock);
+ ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
+ if (ret < 0) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ goto error;
+ }
+
+ /*
+ * this shouldn't happen, it means the last relocate
+ * failed
+ */
+ if (ret == 0)
+ BUG(); /* FIXME break ? */
+
+ ret = btrfs_previous_item(chunk_root, path, 0,
+ BTRFS_CHUNK_ITEM_KEY);
+ if (ret) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ ret = 0;
+ break;
+ }
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ btrfs_item_key_to_cpu(leaf, &found_key, slot);
+
+ if (found_key.objectid != key.objectid) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ break;
+ }
+
+ chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
+ chunk_type = btrfs_chunk_type(leaf, chunk);
+
+ if (!counting) {
+ spin_lock(&fs_info->balance_lock);
+ bctl->stat.considered++;
+ spin_unlock(&fs_info->balance_lock);
+ }
+
+ ret = should_balance_chunk(leaf, chunk, found_key.offset);
+
+ btrfs_release_path(path);
+ if (!ret) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ goto loop;
+ }
+
+ if (counting) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ spin_lock(&fs_info->balance_lock);
+ bctl->stat.expected++;
+ spin_unlock(&fs_info->balance_lock);
+
+ if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
+ count_data++;
+ else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
+ count_sys++;
+ else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
+ count_meta++;
+
+ goto loop;
+ }
+
+ /*
+ * Apply limit_min filter, no need to check if the LIMITS
+ * filter is used, limit_min is 0 by default
+ */
+ if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
+ count_data < bctl->data.limit_min)
+ || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) &&
+ count_meta < bctl->meta.limit_min)
+ || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) &&
+ count_sys < bctl->sys.limit_min)) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ goto loop;
+ }
+
+ if (!chunk_reserved) {
+ /*
+ * We may be relocating the only data chunk we have,
+ * which could potentially end up with losing data's
+ * raid profile, so lets allocate an empty one in
+ * advance.
+ */
+ ret = btrfs_may_alloc_data_chunk(fs_info,
+ found_key.offset);
+ if (ret < 0) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ goto error;
+ } else if (ret == 1) {
+ chunk_reserved = 1;
+ }
+ }
+
+ ret = btrfs_relocate_chunk(fs_info, found_key.offset);
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ if (ret == -ENOSPC) {
+ enospc_errors++;
+ } else if (ret == -ETXTBSY) {
+ btrfs_info(fs_info,
+ "skipping relocation of block group %llu due to active swapfile",
+ found_key.offset);
+ ret = 0;
+ } else if (ret) {
+ goto error;
+ } else {
+ spin_lock(&fs_info->balance_lock);
+ bctl->stat.completed++;
+ spin_unlock(&fs_info->balance_lock);
+ }
+loop:
+ if (found_key.offset == 0)
+ break;
+ key.offset = found_key.offset - 1;
+ }
+
+ if (counting) {
+ btrfs_release_path(path);
+ counting = false;
+ goto again;
+ }
+error:
+ btrfs_free_path(path);
+ if (enospc_errors) {
+ btrfs_info(fs_info, "%d enospc errors during balance",
+ enospc_errors);
+ if (!ret)
+ ret = -ENOSPC;
+ }
+
+ return ret;
+}
+
+/**
+ * alloc_profile_is_valid - see if a given profile is valid and reduced
+ * @flags: profile to validate
+ * @extended: if true @flags is treated as an extended profile
+ */
+static int alloc_profile_is_valid(u64 flags, int extended)
+{
+ u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
+ BTRFS_BLOCK_GROUP_PROFILE_MASK);
+
+ flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
+
+ /* 1) check that all other bits are zeroed */
+ if (flags & ~mask)
+ return 0;
+
+ /* 2) see if profile is reduced */
+ if (flags == 0)
+ return !extended; /* "0" is valid for usual profiles */
+
+ return has_single_bit_set(flags);
+}
+
+/*
+ * Validate target profile against allowed profiles and return true if it's OK.
+ * Otherwise print the error message and return false.
+ */
+static inline int validate_convert_profile(struct btrfs_fs_info *fs_info,
+ const struct btrfs_balance_args *bargs,
+ u64 allowed, const char *type)
+{
+ if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
+ return true;
+
+ /* Profile is valid and does not have bits outside of the allowed set */
+ if (alloc_profile_is_valid(bargs->target, 1) &&
+ (bargs->target & ~allowed) == 0)
+ return true;
+
+ btrfs_err(fs_info, "balance: invalid convert %s profile %s",
+ type, btrfs_bg_type_to_raid_name(bargs->target));
+ return false;
+}
+
+/*
+ * Fill @buf with textual description of balance filter flags @bargs, up to
+ * @size_buf including the terminating null. The output may be trimmed if it
+ * does not fit into the provided buffer.
+ */
+static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf,
+ u32 size_buf)
+{
+ int ret;
+ u32 size_bp = size_buf;
+ char *bp = buf;
+ u64 flags = bargs->flags;
+ char tmp_buf[128] = {'\0'};
+
+ if (!flags)
+ return;
+
+#define CHECK_APPEND_NOARG(a) \
+ do { \
+ ret = snprintf(bp, size_bp, (a)); \
+ if (ret < 0 || ret >= size_bp) \
+ goto out_overflow; \
+ size_bp -= ret; \
+ bp += ret; \
+ } while (0)
+
+#define CHECK_APPEND_1ARG(a, v1) \
+ do { \
+ ret = snprintf(bp, size_bp, (a), (v1)); \
+ if (ret < 0 || ret >= size_bp) \
+ goto out_overflow; \
+ size_bp -= ret; \
+ bp += ret; \
+ } while (0)
+
+#define CHECK_APPEND_2ARG(a, v1, v2) \
+ do { \
+ ret = snprintf(bp, size_bp, (a), (v1), (v2)); \
+ if (ret < 0 || ret >= size_bp) \
+ goto out_overflow; \
+ size_bp -= ret; \
+ bp += ret; \
+ } while (0)
+
+ if (flags & BTRFS_BALANCE_ARGS_CONVERT)
+ CHECK_APPEND_1ARG("convert=%s,",
+ btrfs_bg_type_to_raid_name(bargs->target));
+
+ if (flags & BTRFS_BALANCE_ARGS_SOFT)
+ CHECK_APPEND_NOARG("soft,");
+
+ if (flags & BTRFS_BALANCE_ARGS_PROFILES) {
+ btrfs_describe_block_groups(bargs->profiles, tmp_buf,
+ sizeof(tmp_buf));
+ CHECK_APPEND_1ARG("profiles=%s,", tmp_buf);
+ }
+
+ if (flags & BTRFS_BALANCE_ARGS_USAGE)
+ CHECK_APPEND_1ARG("usage=%llu,", bargs->usage);
+
+ if (flags & BTRFS_BALANCE_ARGS_USAGE_RANGE)
+ CHECK_APPEND_2ARG("usage=%u..%u,",
+ bargs->usage_min, bargs->usage_max);
+
+ if (flags & BTRFS_BALANCE_ARGS_DEVID)
+ CHECK_APPEND_1ARG("devid=%llu,", bargs->devid);
+
+ if (flags & BTRFS_BALANCE_ARGS_DRANGE)
+ CHECK_APPEND_2ARG("drange=%llu..%llu,",
+ bargs->pstart, bargs->pend);
+
+ if (flags & BTRFS_BALANCE_ARGS_VRANGE)
+ CHECK_APPEND_2ARG("vrange=%llu..%llu,",
+ bargs->vstart, bargs->vend);
+
+ if (flags & BTRFS_BALANCE_ARGS_LIMIT)
+ CHECK_APPEND_1ARG("limit=%llu,", bargs->limit);
+
+ if (flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)
+ CHECK_APPEND_2ARG("limit=%u..%u,",
+ bargs->limit_min, bargs->limit_max);
+
+ if (flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE)
+ CHECK_APPEND_2ARG("stripes=%u..%u,",
+ bargs->stripes_min, bargs->stripes_max);
+
+#undef CHECK_APPEND_2ARG
+#undef CHECK_APPEND_1ARG
+#undef CHECK_APPEND_NOARG
+
+out_overflow:
+
+ if (size_bp < size_buf)
+ buf[size_buf - size_bp - 1] = '\0'; /* remove last , */
+ else
+ buf[0] = '\0';
+}
+
+static void describe_balance_start_or_resume(struct btrfs_fs_info *fs_info)
+{
+ u32 size_buf = 1024;
+ char tmp_buf[192] = {'\0'};
+ char *buf;
+ char *bp;
+ u32 size_bp = size_buf;
+ int ret;
+ struct btrfs_balance_control *bctl = fs_info->balance_ctl;
+
+ buf = kzalloc(size_buf, GFP_KERNEL);
+ if (!buf)
+ return;
+
+ bp = buf;
+
+#define CHECK_APPEND_1ARG(a, v1) \
+ do { \
+ ret = snprintf(bp, size_bp, (a), (v1)); \
+ if (ret < 0 || ret >= size_bp) \
+ goto out_overflow; \
+ size_bp -= ret; \
+ bp += ret; \
+ } while (0)
+
+ if (bctl->flags & BTRFS_BALANCE_FORCE)
+ CHECK_APPEND_1ARG("%s", "-f ");
+
+ if (bctl->flags & BTRFS_BALANCE_DATA) {
+ describe_balance_args(&bctl->data, tmp_buf, sizeof(tmp_buf));
+ CHECK_APPEND_1ARG("-d%s ", tmp_buf);
+ }
+
+ if (bctl->flags & BTRFS_BALANCE_METADATA) {
+ describe_balance_args(&bctl->meta, tmp_buf, sizeof(tmp_buf));
+ CHECK_APPEND_1ARG("-m%s ", tmp_buf);
+ }
+
+ if (bctl->flags & BTRFS_BALANCE_SYSTEM) {
+ describe_balance_args(&bctl->sys, tmp_buf, sizeof(tmp_buf));
+ CHECK_APPEND_1ARG("-s%s ", tmp_buf);
+ }
+
+#undef CHECK_APPEND_1ARG
+
+out_overflow:
+
+ if (size_bp < size_buf)
+ buf[size_buf - size_bp - 1] = '\0'; /* remove last " " */
+ btrfs_info(fs_info, "balance: %s %s",
+ (bctl->flags & BTRFS_BALANCE_RESUME) ?
+ "resume" : "start", buf);
+
+ kfree(buf);
+}
+
+/*
+ * Should be called with balance mutexe held
+ */
+int btrfs_balance(struct btrfs_fs_info *fs_info,
+ struct btrfs_balance_control *bctl,
+ struct btrfs_ioctl_balance_args *bargs)
+{
+ u64 meta_target, data_target;
+ u64 allowed;
+ int mixed = 0;
+ int ret;
+ u64 num_devices;
+ unsigned seq;
+ bool reducing_redundancy;
+ bool paused = false;
+ int i;
+
+ if (btrfs_fs_closing(fs_info) ||
+ atomic_read(&fs_info->balance_pause_req) ||
+ btrfs_should_cancel_balance(fs_info)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ allowed = btrfs_super_incompat_flags(fs_info->super_copy);
+ if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
+ mixed = 1;
+
+ /*
+ * In case of mixed groups both data and meta should be picked,
+ * and identical options should be given for both of them.
+ */
+ allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
+ if (mixed && (bctl->flags & allowed)) {
+ if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
+ !(bctl->flags & BTRFS_BALANCE_METADATA) ||
+ memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
+ btrfs_err(fs_info,
+ "balance: mixed groups data and metadata options must be the same");
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ /*
+ * rw_devices will not change at the moment, device add/delete/replace
+ * are exclusive
+ */
+ num_devices = fs_info->fs_devices->rw_devices;
+
+ /*
+ * SINGLE profile on-disk has no profile bit, but in-memory we have a
+ * special bit for it, to make it easier to distinguish. Thus we need
+ * to set it manually, or balance would refuse the profile.
+ */
+ allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
+ for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++)
+ if (num_devices >= btrfs_raid_array[i].devs_min)
+ allowed |= btrfs_raid_array[i].bg_flag;
+
+ if (!validate_convert_profile(fs_info, &bctl->data, allowed, "data") ||
+ !validate_convert_profile(fs_info, &bctl->meta, allowed, "metadata") ||
+ !validate_convert_profile(fs_info, &bctl->sys, allowed, "system")) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /*
+ * Allow to reduce metadata or system integrity only if force set for
+ * profiles with redundancy (copies, parity)
+ */
+ allowed = 0;
+ for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) {
+ if (btrfs_raid_array[i].ncopies >= 2 ||
+ btrfs_raid_array[i].tolerated_failures >= 1)
+ allowed |= btrfs_raid_array[i].bg_flag;
+ }
+ do {
+ seq = read_seqbegin(&fs_info->profiles_lock);
+
+ if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
+ (fs_info->avail_system_alloc_bits & allowed) &&
+ !(bctl->sys.target & allowed)) ||
+ ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
+ (fs_info->avail_metadata_alloc_bits & allowed) &&
+ !(bctl->meta.target & allowed)))
+ reducing_redundancy = true;
+ else
+ reducing_redundancy = false;
+
+ /* if we're not converting, the target field is uninitialized */
+ meta_target = (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
+ bctl->meta.target : fs_info->avail_metadata_alloc_bits;
+ data_target = (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
+ bctl->data.target : fs_info->avail_data_alloc_bits;
+ } while (read_seqretry(&fs_info->profiles_lock, seq));
+
+ if (reducing_redundancy) {
+ if (bctl->flags & BTRFS_BALANCE_FORCE) {
+ btrfs_info(fs_info,
+ "balance: force reducing metadata redundancy");
+ } else {
+ btrfs_err(fs_info,
+ "balance: reduces metadata redundancy, use --force if you want this");
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) <
+ btrfs_get_num_tolerated_disk_barrier_failures(data_target)) {
+ btrfs_warn(fs_info,
+ "balance: metadata profile %s has lower redundancy than data profile %s",
+ btrfs_bg_type_to_raid_name(meta_target),
+ btrfs_bg_type_to_raid_name(data_target));
+ }
+
+ ret = insert_balance_item(fs_info, bctl);
+ if (ret && ret != -EEXIST)
+ goto out;
+
+ if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
+ BUG_ON(ret == -EEXIST);
+ BUG_ON(fs_info->balance_ctl);
+ spin_lock(&fs_info->balance_lock);
+ fs_info->balance_ctl = bctl;
+ spin_unlock(&fs_info->balance_lock);
+ } else {
+ BUG_ON(ret != -EEXIST);
+ spin_lock(&fs_info->balance_lock);
+ update_balance_args(bctl);
+ spin_unlock(&fs_info->balance_lock);
+ }
+
+ ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
+ set_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
+ describe_balance_start_or_resume(fs_info);
+ mutex_unlock(&fs_info->balance_mutex);
+
+ ret = __btrfs_balance(fs_info);
+
+ mutex_lock(&fs_info->balance_mutex);
+ if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
+ btrfs_info(fs_info, "balance: paused");
+ btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
+ paused = true;
+ }
+ /*
+ * Balance can be canceled by:
+ *
+ * - Regular cancel request
+ * Then ret == -ECANCELED and balance_cancel_req > 0
+ *
+ * - Fatal signal to "btrfs" process
+ * Either the signal caught by wait_reserve_ticket() and callers
+ * got -EINTR, or caught by btrfs_should_cancel_balance() and
+ * got -ECANCELED.
+ * Either way, in this case balance_cancel_req = 0, and
+ * ret == -EINTR or ret == -ECANCELED.
+ *
+ * So here we only check the return value to catch canceled balance.
+ */
+ else if (ret == -ECANCELED || ret == -EINTR)
+ btrfs_info(fs_info, "balance: canceled");
+ else
+ btrfs_info(fs_info, "balance: ended with status: %d", ret);
+
+ clear_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
+
+ if (bargs) {
+ memset(bargs, 0, sizeof(*bargs));
+ btrfs_update_ioctl_balance_args(fs_info, bargs);
+ }
+
+ /* We didn't pause, we can clean everything up. */
+ if (!paused) {
+ reset_balance_state(fs_info);
+ btrfs_exclop_finish(fs_info);
+ }
+
+ wake_up(&fs_info->balance_wait_q);
+
+ return ret;
+out:
+ if (bctl->flags & BTRFS_BALANCE_RESUME)
+ reset_balance_state(fs_info);
+ else
+ kfree(bctl);
+ btrfs_exclop_finish(fs_info);
+
+ return ret;
+}
+
+static int balance_kthread(void *data)
+{
+ struct btrfs_fs_info *fs_info = data;
+ int ret = 0;
+
+ sb_start_write(fs_info->sb);
+ mutex_lock(&fs_info->balance_mutex);
+ if (fs_info->balance_ctl)
+ ret = btrfs_balance(fs_info, fs_info->balance_ctl, NULL);
+ mutex_unlock(&fs_info->balance_mutex);
+ sb_end_write(fs_info->sb);
+
+ return ret;
+}
+
+int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
+{
+ struct task_struct *tsk;
+
+ mutex_lock(&fs_info->balance_mutex);
+ if (!fs_info->balance_ctl) {
+ mutex_unlock(&fs_info->balance_mutex);
+ return 0;
+ }
+ mutex_unlock(&fs_info->balance_mutex);
+
+ if (btrfs_test_opt(fs_info, SKIP_BALANCE)) {
+ btrfs_info(fs_info, "balance: resume skipped");
+ return 0;
+ }
+
+ spin_lock(&fs_info->super_lock);
+ ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
+ fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
+ spin_unlock(&fs_info->super_lock);
+ /*
+ * A ro->rw remount sequence should continue with the paused balance
+ * regardless of who pauses it, system or the user as of now, so set
+ * the resume flag.
+ */
+ spin_lock(&fs_info->balance_lock);
+ fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME;
+ spin_unlock(&fs_info->balance_lock);
+
+ tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
+ return PTR_ERR_OR_ZERO(tsk);
+}
+
+int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_balance_control *bctl;
+ struct btrfs_balance_item *item;
+ struct btrfs_disk_balance_args disk_bargs;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = BTRFS_BALANCE_OBJECTID;
+ key.type = BTRFS_TEMPORARY_ITEM_KEY;
+ key.offset = 0;
+
+ ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) { /* ret = -ENOENT; */
+ ret = 0;
+ goto out;
+ }
+
+ bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
+ if (!bctl) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ leaf = path->nodes[0];
+ item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
+
+ bctl->flags = btrfs_balance_flags(leaf, item);
+ bctl->flags |= BTRFS_BALANCE_RESUME;
+
+ btrfs_balance_data(leaf, item, &disk_bargs);
+ btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
+ btrfs_balance_meta(leaf, item, &disk_bargs);
+ btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
+ btrfs_balance_sys(leaf, item, &disk_bargs);
+ btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
+
+ /*
+ * This should never happen, as the paused balance state is recovered
+ * during mount without any chance of other exclusive ops to collide.
+ *
+ * This gives the exclusive op status to balance and keeps in paused
+ * state until user intervention (cancel or umount). If the ownership
+ * cannot be assigned, show a message but do not fail. The balance
+ * is in a paused state and must have fs_info::balance_ctl properly
+ * set up.
+ */
+ if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED))
+ btrfs_warn(fs_info,
+ "balance: cannot set exclusive op status, resume manually");
+
+ btrfs_release_path(path);
+
+ mutex_lock(&fs_info->balance_mutex);
+ BUG_ON(fs_info->balance_ctl);
+ spin_lock(&fs_info->balance_lock);
+ fs_info->balance_ctl = bctl;
+ spin_unlock(&fs_info->balance_lock);
+ mutex_unlock(&fs_info->balance_mutex);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
+{
+ int ret = 0;
+
+ mutex_lock(&fs_info->balance_mutex);
+ if (!fs_info->balance_ctl) {
+ mutex_unlock(&fs_info->balance_mutex);
+ return -ENOTCONN;
+ }
+
+ if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
+ atomic_inc(&fs_info->balance_pause_req);
+ mutex_unlock(&fs_info->balance_mutex);
+
+ wait_event(fs_info->balance_wait_q,
+ !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
+
+ mutex_lock(&fs_info->balance_mutex);
+ /* we are good with balance_ctl ripped off from under us */
+ BUG_ON(test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
+ atomic_dec(&fs_info->balance_pause_req);
+ } else {
+ ret = -ENOTCONN;
+ }
+
+ mutex_unlock(&fs_info->balance_mutex);
+ return ret;
+}
+
+int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
+{
+ mutex_lock(&fs_info->balance_mutex);
+ if (!fs_info->balance_ctl) {
+ mutex_unlock(&fs_info->balance_mutex);
+ return -ENOTCONN;
+ }
+
+ /*
+ * A paused balance with the item stored on disk can be resumed at
+ * mount time if the mount is read-write. Otherwise it's still paused
+ * and we must not allow cancelling as it deletes the item.
+ */
+ if (sb_rdonly(fs_info->sb)) {
+ mutex_unlock(&fs_info->balance_mutex);
+ return -EROFS;
+ }
+
+ atomic_inc(&fs_info->balance_cancel_req);
+ /*
+ * if we are running just wait and return, balance item is
+ * deleted in btrfs_balance in this case
+ */
+ if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
+ mutex_unlock(&fs_info->balance_mutex);
+ wait_event(fs_info->balance_wait_q,
+ !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
+ mutex_lock(&fs_info->balance_mutex);
+ } else {
+ mutex_unlock(&fs_info->balance_mutex);
+ /*
+ * Lock released to allow other waiters to continue, we'll
+ * reexamine the status again.
+ */
+ mutex_lock(&fs_info->balance_mutex);
+
+ if (fs_info->balance_ctl) {
+ reset_balance_state(fs_info);
+ btrfs_exclop_finish(fs_info);
+ btrfs_info(fs_info, "balance: canceled");
+ }
+ }
+
+ ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
+ atomic_dec(&fs_info->balance_cancel_req);
+ mutex_unlock(&fs_info->balance_mutex);
+ return 0;
+}
+
+int btrfs_uuid_scan_kthread(void *data)
+{
+ struct btrfs_fs_info *fs_info = data;
+ struct btrfs_root *root = fs_info->tree_root;
+ struct btrfs_key key;
+ struct btrfs_path *path = NULL;
+ int ret = 0;
+ struct extent_buffer *eb;
+ int slot;
+ struct btrfs_root_item root_item;
+ u32 item_size;
+ struct btrfs_trans_handle *trans = NULL;
+ bool closing = false;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ key.objectid = 0;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+ key.offset = 0;
+
+ while (1) {
+ if (btrfs_fs_closing(fs_info)) {
+ closing = true;
+ break;
+ }
+ ret = btrfs_search_forward(root, &key, path,
+ BTRFS_OLDEST_GENERATION);
+ if (ret) {
+ if (ret > 0)
+ ret = 0;
+ break;
+ }
+
+ if (key.type != BTRFS_ROOT_ITEM_KEY ||
+ (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
+ key.objectid != BTRFS_FS_TREE_OBJECTID) ||
+ key.objectid > BTRFS_LAST_FREE_OBJECTID)
+ goto skip;
+
+ eb = path->nodes[0];
+ slot = path->slots[0];
+ item_size = btrfs_item_size(eb, slot);
+ if (item_size < sizeof(root_item))
+ goto skip;
+
+ read_extent_buffer(eb, &root_item,
+ btrfs_item_ptr_offset(eb, slot),
+ (int)sizeof(root_item));
+ if (btrfs_root_refs(&root_item) == 0)
+ goto skip;
+
+ if (!btrfs_is_empty_uuid(root_item.uuid) ||
+ !btrfs_is_empty_uuid(root_item.received_uuid)) {
+ if (trans)
+ goto update_tree;
+
+ btrfs_release_path(path);
+ /*
+ * 1 - subvol uuid item
+ * 1 - received_subvol uuid item
+ */
+ trans = btrfs_start_transaction(fs_info->uuid_root, 2);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ break;
+ }
+ continue;
+ } else {
+ goto skip;
+ }
+update_tree:
+ btrfs_release_path(path);
+ if (!btrfs_is_empty_uuid(root_item.uuid)) {
+ ret = btrfs_uuid_tree_add(trans, root_item.uuid,
+ BTRFS_UUID_KEY_SUBVOL,
+ key.objectid);
+ if (ret < 0) {
+ btrfs_warn(fs_info, "uuid_tree_add failed %d",
+ ret);
+ break;
+ }
+ }
+
+ if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
+ ret = btrfs_uuid_tree_add(trans,
+ root_item.received_uuid,
+ BTRFS_UUID_KEY_RECEIVED_SUBVOL,
+ key.objectid);
+ if (ret < 0) {
+ btrfs_warn(fs_info, "uuid_tree_add failed %d",
+ ret);
+ break;
+ }
+ }
+
+skip:
+ btrfs_release_path(path);
+ if (trans) {
+ ret = btrfs_end_transaction(trans);
+ trans = NULL;
+ if (ret)
+ break;
+ }
+
+ if (key.offset < (u64)-1) {
+ key.offset++;
+ } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
+ key.offset = 0;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+ } else if (key.objectid < (u64)-1) {
+ key.offset = 0;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+ key.objectid++;
+ } else {
+ break;
+ }
+ cond_resched();
+ }
+
+out:
+ btrfs_free_path(path);
+ if (trans && !IS_ERR(trans))
+ btrfs_end_transaction(trans);
+ if (ret)
+ btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
+ else if (!closing)
+ set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
+ up(&fs_info->uuid_tree_rescan_sem);
+ return 0;
+}
+
+int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct btrfs_root *uuid_root;
+ struct task_struct *task;
+ int ret;
+
+ /*
+ * 1 - root node
+ * 1 - root item
+ */
+ trans = btrfs_start_transaction(tree_root, 2);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
+ uuid_root = btrfs_create_tree(trans, BTRFS_UUID_TREE_OBJECTID);
+ if (IS_ERR(uuid_root)) {
+ ret = PTR_ERR(uuid_root);
+ btrfs_abort_transaction(trans, ret);
+ btrfs_end_transaction(trans);
+ return ret;
+ }
+
+ fs_info->uuid_root = uuid_root;
+
+ ret = btrfs_commit_transaction(trans);
+ if (ret)
+ return ret;
+
+ down(&fs_info->uuid_tree_rescan_sem);
+ task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
+ if (IS_ERR(task)) {
+ /* fs_info->update_uuid_tree_gen remains 0 in all error case */
+ btrfs_warn(fs_info, "failed to start uuid_scan task");
+ up(&fs_info->uuid_tree_rescan_sem);
+ return PTR_ERR(task);
+ }
+
+ return 0;
+}
+
+/*
+ * shrinking a device means finding all of the device extents past
+ * the new size, and then following the back refs to the chunks.
+ * The chunk relocation code actually frees the device extent
+ */
+int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
+{
+ struct btrfs_fs_info *fs_info = device->fs_info;
+ struct btrfs_root *root = fs_info->dev_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_dev_extent *dev_extent = NULL;
+ struct btrfs_path *path;
+ u64 length;
+ u64 chunk_offset;
+ int ret;
+ int slot;
+ int failed = 0;
+ bool retried = false;
+ struct extent_buffer *l;
+ struct btrfs_key key;
+ struct btrfs_super_block *super_copy = fs_info->super_copy;
+ u64 old_total = btrfs_super_total_bytes(super_copy);
+ u64 old_size = btrfs_device_get_total_bytes(device);
+ u64 diff;
+ u64 start;
+
+ new_size = round_down(new_size, fs_info->sectorsize);
+ start = new_size;
+ diff = round_down(old_size - new_size, fs_info->sectorsize);
+
+ if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
+ return -EINVAL;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ path->reada = READA_BACK;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ btrfs_free_path(path);
+ return PTR_ERR(trans);
+ }
+
+ mutex_lock(&fs_info->chunk_mutex);
+
+ btrfs_device_set_total_bytes(device, new_size);
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ device->fs_devices->total_rw_bytes -= diff;
+ atomic64_sub(diff, &fs_info->free_chunk_space);
+ }
+
+ /*
+ * Once the device's size has been set to the new size, ensure all
+ * in-memory chunks are synced to disk so that the loop below sees them
+ * and relocates them accordingly.
+ */
+ if (contains_pending_extent(device, &start, diff)) {
+ mutex_unlock(&fs_info->chunk_mutex);
+ ret = btrfs_commit_transaction(trans);
+ if (ret)
+ goto done;
+ } else {
+ mutex_unlock(&fs_info->chunk_mutex);
+ btrfs_end_transaction(trans);
+ }
+
+again:
+ key.objectid = device->devid;
+ key.offset = (u64)-1;
+ key.type = BTRFS_DEV_EXTENT_KEY;
+
+ do {
+ mutex_lock(&fs_info->reclaim_bgs_lock);
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ goto done;
+ }
+
+ ret = btrfs_previous_item(root, path, 0, key.type);
+ if (ret) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ if (ret < 0)
+ goto done;
+ ret = 0;
+ btrfs_release_path(path);
+ break;
+ }
+
+ l = path->nodes[0];
+ slot = path->slots[0];
+ btrfs_item_key_to_cpu(l, &key, path->slots[0]);
+
+ if (key.objectid != device->devid) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ btrfs_release_path(path);
+ break;
+ }
+
+ dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
+ length = btrfs_dev_extent_length(l, dev_extent);
+
+ if (key.offset + length <= new_size) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ btrfs_release_path(path);
+ break;
+ }
+
+ chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
+ btrfs_release_path(path);
+
+ /*
+ * We may be relocating the only data chunk we have,
+ * which could potentially end up with losing data's
+ * raid profile, so lets allocate an empty one in
+ * advance.
+ */
+ ret = btrfs_may_alloc_data_chunk(fs_info, chunk_offset);
+ if (ret < 0) {
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ goto done;
+ }
+
+ ret = btrfs_relocate_chunk(fs_info, chunk_offset);
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ if (ret == -ENOSPC) {
+ failed++;
+ } else if (ret) {
+ if (ret == -ETXTBSY) {
+ btrfs_warn(fs_info,
+ "could not shrink block group %llu due to active swapfile",
+ chunk_offset);
+ }
+ goto done;
+ }
+ } while (key.offset-- > 0);
+
+ if (failed && !retried) {
+ failed = 0;
+ retried = true;
+ goto again;
+ } else if (failed && retried) {
+ ret = -ENOSPC;
+ goto done;
+ }
+
+ /* Shrinking succeeded, else we would be at "done". */
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto done;
+ }
+
+ mutex_lock(&fs_info->chunk_mutex);
+ /* Clear all state bits beyond the shrunk device size */
+ clear_extent_bits(&device->alloc_state, new_size, (u64)-1,
+ CHUNK_STATE_MASK);
+
+ btrfs_device_set_disk_total_bytes(device, new_size);
+ if (list_empty(&device->post_commit_list))
+ list_add_tail(&device->post_commit_list,
+ &trans->transaction->dev_update_list);
+
+ WARN_ON(diff > old_total);
+ btrfs_set_super_total_bytes(super_copy,
+ round_down(old_total - diff, fs_info->sectorsize));
+ mutex_unlock(&fs_info->chunk_mutex);
+
+ btrfs_reserve_chunk_metadata(trans, false);
+ /* Now btrfs_update_device() will change the on-disk size. */
+ ret = btrfs_update_device(trans, device);
+ btrfs_trans_release_chunk_metadata(trans);
+ if (ret < 0) {
+ btrfs_abort_transaction(trans, ret);
+ btrfs_end_transaction(trans);
+ } else {
+ ret = btrfs_commit_transaction(trans);
+ }
+done:
+ btrfs_free_path(path);
+ if (ret) {
+ mutex_lock(&fs_info->chunk_mutex);
+ btrfs_device_set_total_bytes(device, old_size);
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
+ device->fs_devices->total_rw_bytes += diff;
+ atomic64_add(diff, &fs_info->free_chunk_space);
+ mutex_unlock(&fs_info->chunk_mutex);
+ }
+ return ret;
+}
+
+static int btrfs_add_system_chunk(struct btrfs_fs_info *fs_info,
+ struct btrfs_key *key,
+ struct btrfs_chunk *chunk, int item_size)
+{
+ struct btrfs_super_block *super_copy = fs_info->super_copy;
+ struct btrfs_disk_key disk_key;
+ u32 array_size;
+ u8 *ptr;
+
+ lockdep_assert_held(&fs_info->chunk_mutex);
+
+ array_size = btrfs_super_sys_array_size(super_copy);
+ if (array_size + item_size + sizeof(disk_key)
+ > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
+ return -EFBIG;
+
+ ptr = super_copy->sys_chunk_array + array_size;
+ btrfs_cpu_key_to_disk(&disk_key, key);
+ memcpy(ptr, &disk_key, sizeof(disk_key));
+ ptr += sizeof(disk_key);
+ memcpy(ptr, chunk, item_size);
+ item_size += sizeof(disk_key);
+ btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
+
+ return 0;
+}
+
+/*
+ * sort the devices in descending order by max_avail, total_avail
+ */
+static int btrfs_cmp_device_info(const void *a, const void *b)
+{
+ const struct btrfs_device_info *di_a = a;
+ const struct btrfs_device_info *di_b = b;
+
+ if (di_a->max_avail > di_b->max_avail)
+ return -1;
+ if (di_a->max_avail < di_b->max_avail)
+ return 1;
+ if (di_a->total_avail > di_b->total_avail)
+ return -1;
+ if (di_a->total_avail < di_b->total_avail)
+ return 1;
+ return 0;
+}
+
+static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
+{
+ if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
+ return;
+
+ btrfs_set_fs_incompat(info, RAID56);
+}
+
+static void check_raid1c34_incompat_flag(struct btrfs_fs_info *info, u64 type)
+{
+ if (!(type & (BTRFS_BLOCK_GROUP_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4)))
+ return;
+
+ btrfs_set_fs_incompat(info, RAID1C34);
+}
+
+/*
+ * Structure used internally for btrfs_create_chunk() function.
+ * Wraps needed parameters.
+ */
+struct alloc_chunk_ctl {
+ u64 start;
+ u64 type;
+ /* Total number of stripes to allocate */
+ int num_stripes;
+ /* sub_stripes info for map */
+ int sub_stripes;
+ /* Stripes per device */
+ int dev_stripes;
+ /* Maximum number of devices to use */
+ int devs_max;
+ /* Minimum number of devices to use */
+ int devs_min;
+ /* ndevs has to be a multiple of this */
+ int devs_increment;
+ /* Number of copies */
+ int ncopies;
+ /* Number of stripes worth of bytes to store parity information */
+ int nparity;
+ u64 max_stripe_size;
+ u64 max_chunk_size;
+ u64 dev_extent_min;
+ u64 stripe_size;
+ u64 chunk_size;
+ int ndevs;
+};
+
+static void init_alloc_chunk_ctl_policy_regular(
+ struct btrfs_fs_devices *fs_devices,
+ struct alloc_chunk_ctl *ctl)
+{
+ struct btrfs_space_info *space_info;
+
+ space_info = btrfs_find_space_info(fs_devices->fs_info, ctl->type);
+ ASSERT(space_info);
+
+ ctl->max_chunk_size = READ_ONCE(space_info->chunk_size);
+ ctl->max_stripe_size = min_t(u64, ctl->max_chunk_size, SZ_1G);
+
+ if (ctl->type & BTRFS_BLOCK_GROUP_SYSTEM)
+ ctl->devs_max = min_t(int, ctl->devs_max, BTRFS_MAX_DEVS_SYS_CHUNK);
+
+ /* We don't want a chunk larger than 10% of writable space */
+ ctl->max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
+ ctl->max_chunk_size);
+ ctl->dev_extent_min = BTRFS_STRIPE_LEN * ctl->dev_stripes;
+}
+
+static void init_alloc_chunk_ctl_policy_zoned(
+ struct btrfs_fs_devices *fs_devices,
+ struct alloc_chunk_ctl *ctl)
+{
+ u64 zone_size = fs_devices->fs_info->zone_size;
+ u64 limit;
+ int min_num_stripes = ctl->devs_min * ctl->dev_stripes;
+ int min_data_stripes = (min_num_stripes - ctl->nparity) / ctl->ncopies;
+ u64 min_chunk_size = min_data_stripes * zone_size;
+ u64 type = ctl->type;
+
+ ctl->max_stripe_size = zone_size;
+ if (type & BTRFS_BLOCK_GROUP_DATA) {
+ ctl->max_chunk_size = round_down(BTRFS_MAX_DATA_CHUNK_SIZE,
+ zone_size);
+ } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
+ ctl->max_chunk_size = ctl->max_stripe_size;
+ } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
+ ctl->max_chunk_size = 2 * ctl->max_stripe_size;
+ ctl->devs_max = min_t(int, ctl->devs_max,
+ BTRFS_MAX_DEVS_SYS_CHUNK);
+ } else {
+ BUG();
+ }
+
+ /* We don't want a chunk larger than 10% of writable space */
+ limit = max(round_down(div_factor(fs_devices->total_rw_bytes, 1),
+ zone_size),
+ min_chunk_size);
+ ctl->max_chunk_size = min(limit, ctl->max_chunk_size);
+ ctl->dev_extent_min = zone_size * ctl->dev_stripes;
+}
+
+static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices,
+ struct alloc_chunk_ctl *ctl)
+{
+ int index = btrfs_bg_flags_to_raid_index(ctl->type);
+
+ ctl->sub_stripes = btrfs_raid_array[index].sub_stripes;
+ ctl->dev_stripes = btrfs_raid_array[index].dev_stripes;
+ ctl->devs_max = btrfs_raid_array[index].devs_max;
+ if (!ctl->devs_max)
+ ctl->devs_max = BTRFS_MAX_DEVS(fs_devices->fs_info);
+ ctl->devs_min = btrfs_raid_array[index].devs_min;
+ ctl->devs_increment = btrfs_raid_array[index].devs_increment;
+ ctl->ncopies = btrfs_raid_array[index].ncopies;
+ ctl->nparity = btrfs_raid_array[index].nparity;
+ ctl->ndevs = 0;
+
+ switch (fs_devices->chunk_alloc_policy) {
+ case BTRFS_CHUNK_ALLOC_REGULAR:
+ init_alloc_chunk_ctl_policy_regular(fs_devices, ctl);
+ break;
+ case BTRFS_CHUNK_ALLOC_ZONED:
+ init_alloc_chunk_ctl_policy_zoned(fs_devices, ctl);
+ break;
+ default:
+ BUG();
+ }
+}
+
+static int gather_device_info(struct btrfs_fs_devices *fs_devices,
+ struct alloc_chunk_ctl *ctl,
+ struct btrfs_device_info *devices_info)
+{
+ struct btrfs_fs_info *info = fs_devices->fs_info;
+ struct btrfs_device *device;
+ u64 total_avail;
+ u64 dev_extent_want = ctl->max_stripe_size * ctl->dev_stripes;
+ int ret;
+ int ndevs = 0;
+ u64 max_avail;
+ u64 dev_offset;
+
+ /*
+ * in the first pass through the devices list, we gather information
+ * about the available holes on each device.
+ */
+ list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
+ if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ WARN(1, KERN_ERR
+ "BTRFS: read-only device in alloc_list\n");
+ continue;
+ }
+
+ if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
+ &device->dev_state) ||
+ test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
+ continue;
+
+ if (device->total_bytes > device->bytes_used)
+ total_avail = device->total_bytes - device->bytes_used;
+ else
+ total_avail = 0;
+
+ /* If there is no space on this device, skip it. */
+ if (total_avail < ctl->dev_extent_min)
+ continue;
+
+ ret = find_free_dev_extent(device, dev_extent_want, &dev_offset,
+ &max_avail);
+ if (ret && ret != -ENOSPC)
+ return ret;
+
+ if (ret == 0)
+ max_avail = dev_extent_want;
+
+ if (max_avail < ctl->dev_extent_min) {
+ if (btrfs_test_opt(info, ENOSPC_DEBUG))
+ btrfs_debug(info,
+ "%s: devid %llu has no free space, have=%llu want=%llu",
+ __func__, device->devid, max_avail,
+ ctl->dev_extent_min);
+ continue;
+ }
+
+ if (ndevs == fs_devices->rw_devices) {
+ WARN(1, "%s: found more than %llu devices\n",
+ __func__, fs_devices->rw_devices);
+ break;
+ }
+ devices_info[ndevs].dev_offset = dev_offset;
+ devices_info[ndevs].max_avail = max_avail;
+ devices_info[ndevs].total_avail = total_avail;
+ devices_info[ndevs].dev = device;
+ ++ndevs;
+ }
+ ctl->ndevs = ndevs;
+
+ /*
+ * now sort the devices by hole size / available space
+ */
+ sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
+ btrfs_cmp_device_info, NULL);
+
+ return 0;
+}
+
+static int decide_stripe_size_regular(struct alloc_chunk_ctl *ctl,
+ struct btrfs_device_info *devices_info)
+{
+ /* Number of stripes that count for block group size */
+ int data_stripes;
+
+ /*
+ * The primary goal is to maximize the number of stripes, so use as
+ * many devices as possible, even if the stripes are not maximum sized.
+ *
+ * The DUP profile stores more than one stripe per device, the
+ * max_avail is the total size so we have to adjust.
+ */
+ ctl->stripe_size = div_u64(devices_info[ctl->ndevs - 1].max_avail,
+ ctl->dev_stripes);
+ ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
+
+ /* This will have to be fixed for RAID1 and RAID10 over more drives */
+ data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
+
+ /*
+ * Use the number of data stripes to figure out how big this chunk is
+ * really going to be in terms of logical address space, and compare
+ * that answer with the max chunk size. If it's higher, we try to
+ * reduce stripe_size.
+ */
+ if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
+ /*
+ * Reduce stripe_size, round it up to a 16MB boundary again and
+ * then use it, unless it ends up being even bigger than the
+ * previous value we had already.
+ */
+ ctl->stripe_size = min(round_up(div_u64(ctl->max_chunk_size,
+ data_stripes), SZ_16M),
+ ctl->stripe_size);
+ }
+
+ /* Stripe size should not go beyond 1G. */
+ ctl->stripe_size = min_t(u64, ctl->stripe_size, SZ_1G);
+
+ /* Align to BTRFS_STRIPE_LEN */
+ ctl->stripe_size = round_down(ctl->stripe_size, BTRFS_STRIPE_LEN);
+ ctl->chunk_size = ctl->stripe_size * data_stripes;
+
+ return 0;
+}
+
+static int decide_stripe_size_zoned(struct alloc_chunk_ctl *ctl,
+ struct btrfs_device_info *devices_info)
+{
+ u64 zone_size = devices_info[0].dev->zone_info->zone_size;
+ /* Number of stripes that count for block group size */
+ int data_stripes;
+
+ /*
+ * It should hold because:
+ * dev_extent_min == dev_extent_want == zone_size * dev_stripes
+ */
+ ASSERT(devices_info[ctl->ndevs - 1].max_avail == ctl->dev_extent_min);
+
+ ctl->stripe_size = zone_size;
+ ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
+ data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
+
+ /* stripe_size is fixed in zoned filesysmte. Reduce ndevs instead. */
+ if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
+ ctl->ndevs = div_u64(div_u64(ctl->max_chunk_size * ctl->ncopies,
+ ctl->stripe_size) + ctl->nparity,
+ ctl->dev_stripes);
+ ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
+ data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
+ ASSERT(ctl->stripe_size * data_stripes <= ctl->max_chunk_size);
+ }
+
+ ctl->chunk_size = ctl->stripe_size * data_stripes;
+
+ return 0;
+}
+
+static int decide_stripe_size(struct btrfs_fs_devices *fs_devices,
+ struct alloc_chunk_ctl *ctl,
+ struct btrfs_device_info *devices_info)
+{
+ struct btrfs_fs_info *info = fs_devices->fs_info;
+
+ /*
+ * Round down to number of usable stripes, devs_increment can be any
+ * number so we can't use round_down() that requires power of 2, while
+ * rounddown is safe.
+ */
+ ctl->ndevs = rounddown(ctl->ndevs, ctl->devs_increment);
+
+ if (ctl->ndevs < ctl->devs_min) {
+ if (btrfs_test_opt(info, ENOSPC_DEBUG)) {
+ btrfs_debug(info,
+ "%s: not enough devices with free space: have=%d minimum required=%d",
+ __func__, ctl->ndevs, ctl->devs_min);
+ }
+ return -ENOSPC;
+ }
+
+ ctl->ndevs = min(ctl->ndevs, ctl->devs_max);
+
+ switch (fs_devices->chunk_alloc_policy) {
+ case BTRFS_CHUNK_ALLOC_REGULAR:
+ return decide_stripe_size_regular(ctl, devices_info);
+ case BTRFS_CHUNK_ALLOC_ZONED:
+ return decide_stripe_size_zoned(ctl, devices_info);
+ default:
+ BUG();
+ }
+}
+
+static struct btrfs_block_group *create_chunk(struct btrfs_trans_handle *trans,
+ struct alloc_chunk_ctl *ctl,
+ struct btrfs_device_info *devices_info)
+{
+ struct btrfs_fs_info *info = trans->fs_info;
+ struct map_lookup *map = NULL;
+ struct extent_map_tree *em_tree;
+ struct btrfs_block_group *block_group;
+ struct extent_map *em;
+ u64 start = ctl->start;
+ u64 type = ctl->type;
+ int ret;
+ int i;
+ int j;
+
+ map = kmalloc(map_lookup_size(ctl->num_stripes), GFP_NOFS);
+ if (!map)
+ return ERR_PTR(-ENOMEM);
+ map->num_stripes = ctl->num_stripes;
+
+ for (i = 0; i < ctl->ndevs; ++i) {
+ for (j = 0; j < ctl->dev_stripes; ++j) {
+ int s = i * ctl->dev_stripes + j;
+ map->stripes[s].dev = devices_info[i].dev;
+ map->stripes[s].physical = devices_info[i].dev_offset +
+ j * ctl->stripe_size;
+ }
+ }
+ map->stripe_len = BTRFS_STRIPE_LEN;
+ map->io_align = BTRFS_STRIPE_LEN;
+ map->io_width = BTRFS_STRIPE_LEN;
+ map->type = type;
+ map->sub_stripes = ctl->sub_stripes;
+
+ trace_btrfs_chunk_alloc(info, map, start, ctl->chunk_size);
+
+ em = alloc_extent_map();
+ if (!em) {
+ kfree(map);
+ return ERR_PTR(-ENOMEM);
+ }
+ set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
+ em->map_lookup = map;
+ em->start = start;
+ em->len = ctl->chunk_size;
+ em->block_start = 0;
+ em->block_len = em->len;
+ em->orig_block_len = ctl->stripe_size;
+
+ em_tree = &info->mapping_tree;
+ write_lock(&em_tree->lock);
+ ret = add_extent_mapping(em_tree, em, 0);
+ if (ret) {
+ write_unlock(&em_tree->lock);
+ free_extent_map(em);
+ return ERR_PTR(ret);
+ }
+ write_unlock(&em_tree->lock);
+
+ block_group = btrfs_make_block_group(trans, 0, type, start, ctl->chunk_size);
+ if (IS_ERR(block_group))
+ goto error_del_extent;
+
+ for (i = 0; i < map->num_stripes; i++) {
+ struct btrfs_device *dev = map->stripes[i].dev;
+
+ btrfs_device_set_bytes_used(dev,
+ dev->bytes_used + ctl->stripe_size);
+ if (list_empty(&dev->post_commit_list))
+ list_add_tail(&dev->post_commit_list,
+ &trans->transaction->dev_update_list);
+ }
+
+ atomic64_sub(ctl->stripe_size * map->num_stripes,
+ &info->free_chunk_space);
+
+ free_extent_map(em);
+ check_raid56_incompat_flag(info, type);
+ check_raid1c34_incompat_flag(info, type);
+
+ return block_group;
+
+error_del_extent:
+ write_lock(&em_tree->lock);
+ remove_extent_mapping(em_tree, em);
+ write_unlock(&em_tree->lock);
+
+ /* One for our allocation */
+ free_extent_map(em);
+ /* One for the tree reference */
+ free_extent_map(em);
+
+ return block_group;
+}
+
+struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
+ u64 type)
+{
+ struct btrfs_fs_info *info = trans->fs_info;
+ struct btrfs_fs_devices *fs_devices = info->fs_devices;
+ struct btrfs_device_info *devices_info = NULL;
+ struct alloc_chunk_ctl ctl;
+ struct btrfs_block_group *block_group;
+ int ret;
+
+ lockdep_assert_held(&info->chunk_mutex);
+
+ if (!alloc_profile_is_valid(type, 0)) {
+ ASSERT(0);
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (list_empty(&fs_devices->alloc_list)) {
+ if (btrfs_test_opt(info, ENOSPC_DEBUG))
+ btrfs_debug(info, "%s: no writable device", __func__);
+ return ERR_PTR(-ENOSPC);
+ }
+
+ if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
+ btrfs_err(info, "invalid chunk type 0x%llx requested", type);
+ ASSERT(0);
+ return ERR_PTR(-EINVAL);
+ }
+
+ ctl.start = find_next_chunk(info);
+ ctl.type = type;
+ init_alloc_chunk_ctl(fs_devices, &ctl);
+
+ devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
+ GFP_NOFS);
+ if (!devices_info)
+ return ERR_PTR(-ENOMEM);
+
+ ret = gather_device_info(fs_devices, &ctl, devices_info);
+ if (ret < 0) {
+ block_group = ERR_PTR(ret);
+ goto out;
+ }
+
+ ret = decide_stripe_size(fs_devices, &ctl, devices_info);
+ if (ret < 0) {
+ block_group = ERR_PTR(ret);
+ goto out;
+ }
+
+ block_group = create_chunk(trans, &ctl, devices_info);
+
+out:
+ kfree(devices_info);
+ return block_group;
+}
+
+/*
+ * This function, btrfs_chunk_alloc_add_chunk_item(), typically belongs to the
+ * phase 1 of chunk allocation. It belongs to phase 2 only when allocating system
+ * chunks.
+ *
+ * See the comment at btrfs_chunk_alloc() for details about the chunk allocation
+ * phases.
+ */
+int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
+ struct btrfs_block_group *bg)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_root *chunk_root = fs_info->chunk_root;
+ struct btrfs_key key;
+ struct btrfs_chunk *chunk;
+ struct btrfs_stripe *stripe;
+ struct extent_map *em;
+ struct map_lookup *map;
+ size_t item_size;
+ int i;
+ int ret;
+
+ /*
+ * We take the chunk_mutex for 2 reasons:
+ *
+ * 1) Updates and insertions in the chunk btree must be done while holding
+ * the chunk_mutex, as well as updating the system chunk array in the
+ * superblock. See the comment on top of btrfs_chunk_alloc() for the
+ * details;
+ *
+ * 2) To prevent races with the final phase of a device replace operation
+ * that replaces the device object associated with the map's stripes,
+ * because the device object's id can change at any time during that
+ * final phase of the device replace operation
+ * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
+ * replaced device and then see it with an ID of BTRFS_DEV_REPLACE_DEVID,
+ * which would cause a failure when updating the device item, which does
+ * not exists, or persisting a stripe of the chunk item with such ID.
+ * Here we can't use the device_list_mutex because our caller already
+ * has locked the chunk_mutex, and the final phase of device replace
+ * acquires both mutexes - first the device_list_mutex and then the
+ * chunk_mutex. Using any of those two mutexes protects us from a
+ * concurrent device replace.
+ */
+ lockdep_assert_held(&fs_info->chunk_mutex);
+
+ em = btrfs_get_chunk_map(fs_info, bg->start, bg->length);
+ if (IS_ERR(em)) {
+ ret = PTR_ERR(em);
+ btrfs_abort_transaction(trans, ret);
+ return ret;
+ }
+
+ map = em->map_lookup;
+ item_size = btrfs_chunk_item_size(map->num_stripes);
+
+ chunk = kzalloc(item_size, GFP_NOFS);
+ if (!chunk) {
+ ret = -ENOMEM;
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ for (i = 0; i < map->num_stripes; i++) {
+ struct btrfs_device *device = map->stripes[i].dev;
+
+ ret = btrfs_update_device(trans, device);
+ if (ret)
+ goto out;
+ }
+
+ stripe = &chunk->stripe;
+ for (i = 0; i < map->num_stripes; i++) {
+ struct btrfs_device *device = map->stripes[i].dev;
+ const u64 dev_offset = map->stripes[i].physical;
+
+ btrfs_set_stack_stripe_devid(stripe, device->devid);
+ btrfs_set_stack_stripe_offset(stripe, dev_offset);
+ memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
+ stripe++;
+ }
+
+ btrfs_set_stack_chunk_length(chunk, bg->length);
+ btrfs_set_stack_chunk_owner(chunk, BTRFS_EXTENT_TREE_OBJECTID);
+ btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
+ btrfs_set_stack_chunk_type(chunk, map->type);
+ btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
+ btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
+ btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
+ btrfs_set_stack_chunk_sector_size(chunk, fs_info->sectorsize);
+ btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
+
+ key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
+ key.type = BTRFS_CHUNK_ITEM_KEY;
+ key.offset = bg->start;
+
+ ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
+ if (ret)
+ goto out;
+
+ set_bit(BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED, &bg->runtime_flags);
+
+ if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
+ ret = btrfs_add_system_chunk(fs_info, &key, chunk, item_size);
+ if (ret)
+ goto out;
+ }
+
+out:
+ kfree(chunk);
+ free_extent_map(em);
+ return ret;
+}
+
+static noinline int init_first_rw_device(struct btrfs_trans_handle *trans)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ u64 alloc_profile;
+ struct btrfs_block_group *meta_bg;
+ struct btrfs_block_group *sys_bg;
+
+ /*
+ * When adding a new device for sprouting, the seed device is read-only
+ * so we must first allocate a metadata and a system chunk. But before
+ * adding the block group items to the extent, device and chunk btrees,
+ * we must first:
+ *
+ * 1) Create both chunks without doing any changes to the btrees, as
+ * otherwise we would get -ENOSPC since the block groups from the
+ * seed device are read-only;
+ *
+ * 2) Add the device item for the new sprout device - finishing the setup
+ * of a new block group requires updating the device item in the chunk
+ * btree, so it must exist when we attempt to do it. The previous step
+ * ensures this does not fail with -ENOSPC.
+ *
+ * After that we can add the block group items to their btrees:
+ * update existing device item in the chunk btree, add a new block group
+ * item to the extent btree, add a new chunk item to the chunk btree and
+ * finally add the new device extent items to the devices btree.
+ */
+
+ alloc_profile = btrfs_metadata_alloc_profile(fs_info);
+ meta_bg = btrfs_create_chunk(trans, alloc_profile);
+ if (IS_ERR(meta_bg))
+ return PTR_ERR(meta_bg);
+
+ alloc_profile = btrfs_system_alloc_profile(fs_info);
+ sys_bg = btrfs_create_chunk(trans, alloc_profile);
+ if (IS_ERR(sys_bg))
+ return PTR_ERR(sys_bg);
+
+ return 0;
+}
+
+static inline int btrfs_chunk_max_errors(struct map_lookup *map)
+{
+ const int index = btrfs_bg_flags_to_raid_index(map->type);
+
+ return btrfs_raid_array[index].tolerated_failures;
+}
+
+bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset)
+{
+ struct extent_map *em;
+ struct map_lookup *map;
+ int miss_ndevs = 0;
+ int i;
+ bool ret = true;
+
+ em = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
+ if (IS_ERR(em))
+ return false;
+
+ map = em->map_lookup;
+ for (i = 0; i < map->num_stripes; i++) {
+ if (test_bit(BTRFS_DEV_STATE_MISSING,
+ &map->stripes[i].dev->dev_state)) {
+ miss_ndevs++;
+ continue;
+ }
+ if (!test_bit(BTRFS_DEV_STATE_WRITEABLE,
+ &map->stripes[i].dev->dev_state)) {
+ ret = false;
+ goto end;
+ }
+ }
+
+ /*
+ * If the number of missing devices is larger than max errors, we can
+ * not write the data into that chunk successfully.
+ */
+ if (miss_ndevs > btrfs_chunk_max_errors(map))
+ ret = false;
+end:
+ free_extent_map(em);
+ return ret;
+}
+
+void btrfs_mapping_tree_free(struct extent_map_tree *tree)
+{
+ struct extent_map *em;
+
+ while (1) {
+ write_lock(&tree->lock);
+ em = lookup_extent_mapping(tree, 0, (u64)-1);
+ if (em)
+ remove_extent_mapping(tree, em);
+ write_unlock(&tree->lock);
+ if (!em)
+ break;
+ /* once for us */
+ free_extent_map(em);
+ /* once for the tree */
+ free_extent_map(em);
+ }
+}
+
+int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
+{
+ struct extent_map *em;
+ struct map_lookup *map;
+ enum btrfs_raid_types index;
+ int ret = 1;
+
+ em = btrfs_get_chunk_map(fs_info, logical, len);
+ if (IS_ERR(em))
+ /*
+ * We could return errors for these cases, but that could get
+ * ugly and we'd probably do the same thing which is just not do
+ * anything else and exit, so return 1 so the callers don't try
+ * to use other copies.
+ */
+ return 1;
+
+ map = em->map_lookup;
+ index = btrfs_bg_flags_to_raid_index(map->type);
+
+ /* Non-RAID56, use their ncopies from btrfs_raid_array. */
+ if (!(map->type & BTRFS_BLOCK_GROUP_RAID56_MASK))
+ ret = btrfs_raid_array[index].ncopies;
+ else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
+ ret = 2;
+ else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
+ /*
+ * There could be two corrupted data stripes, we need
+ * to loop retry in order to rebuild the correct data.
+ *
+ * Fail a stripe at a time on every retry except the
+ * stripe under reconstruction.
+ */
+ ret = map->num_stripes;
+ free_extent_map(em);
+
+ down_read(&fs_info->dev_replace.rwsem);
+ if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace) &&
+ fs_info->dev_replace.tgtdev)
+ ret++;
+ up_read(&fs_info->dev_replace.rwsem);
+
+ return ret;
+}
+
+unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
+ u64 logical)
+{
+ struct extent_map *em;
+ struct map_lookup *map;
+ unsigned long len = fs_info->sectorsize;
+
+ if (!btrfs_fs_incompat(fs_info, RAID56))
+ return len;
+
+ em = btrfs_get_chunk_map(fs_info, logical, len);
+
+ if (!WARN_ON(IS_ERR(em))) {
+ map = em->map_lookup;
+ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
+ len = map->stripe_len * nr_data_stripes(map);
+ free_extent_map(em);
+ }
+ return len;
+}
+
+int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
+{
+ struct extent_map *em;
+ struct map_lookup *map;
+ int ret = 0;
+
+ if (!btrfs_fs_incompat(fs_info, RAID56))
+ return 0;
+
+ em = btrfs_get_chunk_map(fs_info, logical, len);
+
+ if(!WARN_ON(IS_ERR(em))) {
+ map = em->map_lookup;
+ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
+ ret = 1;
+ free_extent_map(em);
+ }
+ return ret;
+}
+
+static int find_live_mirror(struct btrfs_fs_info *fs_info,
+ struct map_lookup *map, int first,
+ int dev_replace_is_ongoing)
+{
+ int i;
+ int num_stripes;
+ int preferred_mirror;
+ int tolerance;
+ struct btrfs_device *srcdev;
+
+ ASSERT((map->type &
+ (BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10)));
+
+ if (map->type & BTRFS_BLOCK_GROUP_RAID10)
+ num_stripes = map->sub_stripes;
+ else
+ num_stripes = map->num_stripes;
+
+ switch (fs_info->fs_devices->read_policy) {
+ default:
+ /* Shouldn't happen, just warn and use pid instead of failing */
+ btrfs_warn_rl(fs_info,
+ "unknown read_policy type %u, reset to pid",
+ fs_info->fs_devices->read_policy);
+ fs_info->fs_devices->read_policy = BTRFS_READ_POLICY_PID;
+ fallthrough;
+ case BTRFS_READ_POLICY_PID:
+ preferred_mirror = first + (current->pid % num_stripes);
+ break;
+ }
+
+ if (dev_replace_is_ongoing &&
+ fs_info->dev_replace.cont_reading_from_srcdev_mode ==
+ BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
+ srcdev = fs_info->dev_replace.srcdev;
+ else
+ srcdev = NULL;
+
+ /*
+ * try to avoid the drive that is the source drive for a
+ * dev-replace procedure, only choose it if no other non-missing
+ * mirror is available
+ */
+ for (tolerance = 0; tolerance < 2; tolerance++) {
+ if (map->stripes[preferred_mirror].dev->bdev &&
+ (tolerance || map->stripes[preferred_mirror].dev != srcdev))
+ return preferred_mirror;
+ for (i = first; i < first + num_stripes; i++) {
+ if (map->stripes[i].dev->bdev &&
+ (tolerance || map->stripes[i].dev != srcdev))
+ return i;
+ }
+ }
+
+ /* we couldn't find one that doesn't fail. Just return something
+ * and the io error handling code will clean up eventually
+ */
+ return preferred_mirror;
+}
+
+/* Bubble-sort the stripe set to put the parity/syndrome stripes last */
+static void sort_parity_stripes(struct btrfs_io_context *bioc, int num_stripes)
+{
+ int i;
+ int again = 1;
+
+ while (again) {
+ again = 0;
+ for (i = 0; i < num_stripes - 1; i++) {
+ /* Swap if parity is on a smaller index */
+ if (bioc->raid_map[i] > bioc->raid_map[i + 1]) {
+ swap(bioc->stripes[i], bioc->stripes[i + 1]);
+ swap(bioc->raid_map[i], bioc->raid_map[i + 1]);
+ again = 1;
+ }
+ }
+ }
+}
+
+static struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
+ int total_stripes,
+ int real_stripes)
+{
+ struct btrfs_io_context *bioc = kzalloc(
+ /* The size of btrfs_io_context */
+ sizeof(struct btrfs_io_context) +
+ /* Plus the variable array for the stripes */
+ sizeof(struct btrfs_io_stripe) * (total_stripes) +
+ /* Plus the variable array for the tgt dev */
+ sizeof(int) * (real_stripes) +
+ /*
+ * Plus the raid_map, which includes both the tgt dev
+ * and the stripes.
+ */
+ sizeof(u64) * (total_stripes),
+ GFP_NOFS|__GFP_NOFAIL);
+
+ refcount_set(&bioc->refs, 1);
+
+ bioc->fs_info = fs_info;
+ bioc->tgtdev_map = (int *)(bioc->stripes + total_stripes);
+ bioc->raid_map = (u64 *)(bioc->tgtdev_map + real_stripes);
+
+ return bioc;
+}
+
+void btrfs_get_bioc(struct btrfs_io_context *bioc)
+{
+ WARN_ON(!refcount_read(&bioc->refs));
+ refcount_inc(&bioc->refs);
+}
+
+void btrfs_put_bioc(struct btrfs_io_context *bioc)
+{
+ if (!bioc)
+ return;
+ if (refcount_dec_and_test(&bioc->refs))
+ kfree(bioc);
+}
+
+/*
+ * Please note that, discard won't be sent to target device of device
+ * replace.
+ */
+struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 *length_ret,
+ u32 *num_stripes)
+{
+ struct extent_map *em;
+ struct map_lookup *map;
+ struct btrfs_discard_stripe *stripes;
+ u64 length = *length_ret;
+ u64 offset;
+ u64 stripe_nr;
+ u64 stripe_nr_end;
+ u64 stripe_end_offset;
+ u64 stripe_cnt;
+ u64 stripe_len;
+ u64 stripe_offset;
+ u32 stripe_index;
+ u32 factor = 0;
+ u32 sub_stripes = 0;
+ u64 stripes_per_dev = 0;
+ u32 remaining_stripes = 0;
+ u32 last_stripe = 0;
+ int ret;
+ int i;
+
+ em = btrfs_get_chunk_map(fs_info, logical, length);
+ if (IS_ERR(em))
+ return ERR_CAST(em);
+
+ map = em->map_lookup;
+
+ /* we don't discard raid56 yet */
+ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+ ret = -EOPNOTSUPP;
+ goto out_free_map;
+}
+
+ offset = logical - em->start;
+ length = min_t(u64, em->start + em->len - logical, length);
+ *length_ret = length;
+
+ stripe_len = map->stripe_len;
+ /*
+ * stripe_nr counts the total number of stripes we have to stride
+ * to get to this block
+ */
+ stripe_nr = div64_u64(offset, stripe_len);
+
+ /* stripe_offset is the offset of this block in its stripe */
+ stripe_offset = offset - stripe_nr * stripe_len;
+
+ stripe_nr_end = round_up(offset + length, map->stripe_len);
+ stripe_nr_end = div64_u64(stripe_nr_end, map->stripe_len);
+ stripe_cnt = stripe_nr_end - stripe_nr;
+ stripe_end_offset = stripe_nr_end * map->stripe_len -
+ (offset + length);
+ /*
+ * after this, stripe_nr is the number of stripes on this
+ * device we have to walk to find the data, and stripe_index is
+ * the number of our device in the stripe array
+ */
+ *num_stripes = 1;
+ stripe_index = 0;
+ if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
+ BTRFS_BLOCK_GROUP_RAID10)) {
+ if (map->type & BTRFS_BLOCK_GROUP_RAID0)
+ sub_stripes = 1;
+ else
+ sub_stripes = map->sub_stripes;
+
+ factor = map->num_stripes / sub_stripes;
+ *num_stripes = min_t(u64, map->num_stripes,
+ sub_stripes * stripe_cnt);
+ stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
+ stripe_index *= sub_stripes;
+ stripes_per_dev = div_u64_rem(stripe_cnt, factor,
+ &remaining_stripes);
+ div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
+ last_stripe *= sub_stripes;
+ } else if (map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK |
+ BTRFS_BLOCK_GROUP_DUP)) {
+ *num_stripes = map->num_stripes;
+ } else {
+ stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
+ &stripe_index);
+ }
+
+ stripes = kcalloc(*num_stripes, sizeof(*stripes), GFP_NOFS);
+ if (!stripes) {
+ ret = -ENOMEM;
+ goto out_free_map;
+ }
+
+ for (i = 0; i < *num_stripes; i++) {
+ stripes[i].physical =
+ map->stripes[stripe_index].physical +
+ stripe_offset + stripe_nr * map->stripe_len;
+ stripes[i].dev = map->stripes[stripe_index].dev;
+
+ if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
+ BTRFS_BLOCK_GROUP_RAID10)) {
+ stripes[i].length = stripes_per_dev * map->stripe_len;
+
+ if (i / sub_stripes < remaining_stripes)
+ stripes[i].length += map->stripe_len;
+
+ /*
+ * Special for the first stripe and
+ * the last stripe:
+ *
+ * |-------|...|-------|
+ * |----------|
+ * off end_off
+ */
+ if (i < sub_stripes)
+ stripes[i].length -= stripe_offset;
+
+ if (stripe_index >= last_stripe &&
+ stripe_index <= (last_stripe +
+ sub_stripes - 1))
+ stripes[i].length -= stripe_end_offset;
+
+ if (i == sub_stripes - 1)
+ stripe_offset = 0;
+ } else {
+ stripes[i].length = length;
+ }
+
+ stripe_index++;
+ if (stripe_index == map->num_stripes) {
+ stripe_index = 0;
+ stripe_nr++;
+ }
+ }
+
+ free_extent_map(em);
+ return stripes;
+out_free_map:
+ free_extent_map(em);
+ return ERR_PTR(ret);
+}
+
+/*
+ * In dev-replace case, for repair case (that's the only case where the mirror
+ * is selected explicitly when calling btrfs_map_block), blocks left of the
+ * left cursor can also be read from the target drive.
+ *
+ * For REQ_GET_READ_MIRRORS, the target drive is added as the last one to the
+ * array of stripes.
+ * For READ, it also needs to be supported using the same mirror number.
+ *
+ * If the requested block is not left of the left cursor, EIO is returned. This
+ * can happen because btrfs_num_copies() returns one more in the dev-replace
+ * case.
+ */
+static int get_extra_mirror_from_replace(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 length,
+ u64 srcdev_devid, int *mirror_num,
+ u64 *physical)
+{
+ struct btrfs_io_context *bioc = NULL;
+ int num_stripes;
+ int index_srcdev = 0;
+ int found = 0;
+ u64 physical_of_found = 0;
+ int i;
+ int ret = 0;
+
+ ret = __btrfs_map_block(fs_info, BTRFS_MAP_GET_READ_MIRRORS,
+ logical, &length, &bioc, NULL, NULL, 0);
+ if (ret) {
+ ASSERT(bioc == NULL);
+ return ret;
+ }
+
+ num_stripes = bioc->num_stripes;
+ if (*mirror_num > num_stripes) {
+ /*
+ * BTRFS_MAP_GET_READ_MIRRORS does not contain this mirror,
+ * that means that the requested area is not left of the left
+ * cursor
+ */
+ btrfs_put_bioc(bioc);
+ return -EIO;
+ }
+
+ /*
+ * process the rest of the function using the mirror_num of the source
+ * drive. Therefore look it up first. At the end, patch the device
+ * pointer to the one of the target drive.
+ */
+ for (i = 0; i < num_stripes; i++) {
+ if (bioc->stripes[i].dev->devid != srcdev_devid)
+ continue;
+
+ /*
+ * In case of DUP, in order to keep it simple, only add the
+ * mirror with the lowest physical address
+ */
+ if (found &&
+ physical_of_found <= bioc->stripes[i].physical)
+ continue;
+
+ index_srcdev = i;
+ found = 1;
+ physical_of_found = bioc->stripes[i].physical;
+ }
+
+ btrfs_put_bioc(bioc);
+
+ ASSERT(found);
+ if (!found)
+ return -EIO;
+
+ *mirror_num = index_srcdev + 1;
+ *physical = physical_of_found;
+ return ret;
+}
+
+static bool is_block_group_to_copy(struct btrfs_fs_info *fs_info, u64 logical)
+{
+ struct btrfs_block_group *cache;
+ bool ret;
+
+ /* Non zoned filesystem does not use "to_copy" flag */
+ if (!btrfs_is_zoned(fs_info))
+ return false;
+
+ cache = btrfs_lookup_block_group(fs_info, logical);
+
+ ret = test_bit(BLOCK_GROUP_FLAG_TO_COPY, &cache->runtime_flags);
+
+ btrfs_put_block_group(cache);
+ return ret;
+}
+
+static void handle_ops_on_dev_replace(enum btrfs_map_op op,
+ struct btrfs_io_context **bioc_ret,
+ struct btrfs_dev_replace *dev_replace,
+ u64 logical,
+ int *num_stripes_ret, int *max_errors_ret)
+{
+ struct btrfs_io_context *bioc = *bioc_ret;
+ u64 srcdev_devid = dev_replace->srcdev->devid;
+ int tgtdev_indexes = 0;
+ int num_stripes = *num_stripes_ret;
+ int max_errors = *max_errors_ret;
+ int i;
+
+ if (op == BTRFS_MAP_WRITE) {
+ int index_where_to_add;
+
+ /*
+ * A block group which have "to_copy" set will eventually
+ * copied by dev-replace process. We can avoid cloning IO here.
+ */
+ if (is_block_group_to_copy(dev_replace->srcdev->fs_info, logical))
+ return;
+
+ /*
+ * duplicate the write operations while the dev replace
+ * procedure is running. Since the copying of the old disk to
+ * the new disk takes place at run time while the filesystem is
+ * mounted writable, the regular write operations to the old
+ * disk have to be duplicated to go to the new disk as well.
+ *
+ * Note that device->missing is handled by the caller, and that
+ * the write to the old disk is already set up in the stripes
+ * array.
+ */
+ index_where_to_add = num_stripes;
+ for (i = 0; i < num_stripes; i++) {
+ if (bioc->stripes[i].dev->devid == srcdev_devid) {
+ /* write to new disk, too */
+ struct btrfs_io_stripe *new =
+ bioc->stripes + index_where_to_add;
+ struct btrfs_io_stripe *old =
+ bioc->stripes + i;
+
+ new->physical = old->physical;
+ new->dev = dev_replace->tgtdev;
+ bioc->tgtdev_map[i] = index_where_to_add;
+ index_where_to_add++;
+ max_errors++;
+ tgtdev_indexes++;
+ }
+ }
+ num_stripes = index_where_to_add;
+ } else if (op == BTRFS_MAP_GET_READ_MIRRORS) {
+ int index_srcdev = 0;
+ int found = 0;
+ u64 physical_of_found = 0;
+
+ /*
+ * During the dev-replace procedure, the target drive can also
+ * be used to read data in case it is needed to repair a corrupt
+ * block elsewhere. This is possible if the requested area is
+ * left of the left cursor. In this area, the target drive is a
+ * full copy of the source drive.
+ */
+ for (i = 0; i < num_stripes; i++) {
+ if (bioc->stripes[i].dev->devid == srcdev_devid) {
+ /*
+ * In case of DUP, in order to keep it simple,
+ * only add the mirror with the lowest physical
+ * address
+ */
+ if (found &&
+ physical_of_found <= bioc->stripes[i].physical)
+ continue;
+ index_srcdev = i;
+ found = 1;
+ physical_of_found = bioc->stripes[i].physical;
+ }
+ }
+ if (found) {
+ struct btrfs_io_stripe *tgtdev_stripe =
+ bioc->stripes + num_stripes;
+
+ tgtdev_stripe->physical = physical_of_found;
+ tgtdev_stripe->dev = dev_replace->tgtdev;
+ bioc->tgtdev_map[index_srcdev] = num_stripes;
+
+ tgtdev_indexes++;
+ num_stripes++;
+ }
+ }
+
+ *num_stripes_ret = num_stripes;
+ *max_errors_ret = max_errors;
+ bioc->num_tgtdevs = tgtdev_indexes;
+ *bioc_ret = bioc;
+}
+
+static bool need_full_stripe(enum btrfs_map_op op)
+{
+ return (op == BTRFS_MAP_WRITE || op == BTRFS_MAP_GET_READ_MIRRORS);
+}
+
+/*
+ * Calculate the geometry of a particular (address, len) tuple. This
+ * information is used to calculate how big a particular bio can get before it
+ * straddles a stripe.
+ *
+ * @fs_info: the filesystem
+ * @em: mapping containing the logical extent
+ * @op: type of operation - write or read
+ * @logical: address that we want to figure out the geometry of
+ * @io_geom: pointer used to return values
+ *
+ * Returns < 0 in case a chunk for the given logical address cannot be found,
+ * usually shouldn't happen unless @logical is corrupted, 0 otherwise.
+ */
+int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *em,
+ enum btrfs_map_op op, u64 logical,
+ struct btrfs_io_geometry *io_geom)
+{
+ struct map_lookup *map;
+ u64 len;
+ u64 offset;
+ u64 stripe_offset;
+ u64 stripe_nr;
+ u32 stripe_len;
+ u64 raid56_full_stripe_start = (u64)-1;
+ int data_stripes;
+
+ ASSERT(op != BTRFS_MAP_DISCARD);
+
+ map = em->map_lookup;
+ /* Offset of this logical address in the chunk */
+ offset = logical - em->start;
+ /* Len of a stripe in a chunk */
+ stripe_len = map->stripe_len;
+ /*
+ * Stripe_nr is where this block falls in
+ * stripe_offset is the offset of this block in its stripe.
+ */
+ stripe_nr = div64_u64_rem(offset, stripe_len, &stripe_offset);
+ ASSERT(stripe_offset < U32_MAX);
+
+ data_stripes = nr_data_stripes(map);
+
+ /* Only stripe based profiles needs to check against stripe length. */
+ if (map->type & BTRFS_BLOCK_GROUP_STRIPE_MASK) {
+ u64 max_len = stripe_len - stripe_offset;
+
+ /*
+ * In case of raid56, we need to know the stripe aligned start
+ */
+ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+ unsigned long full_stripe_len = stripe_len * data_stripes;
+ raid56_full_stripe_start = offset;
+
+ /*
+ * Allow a write of a full stripe, but make sure we
+ * don't allow straddling of stripes
+ */
+ raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
+ full_stripe_len);
+ raid56_full_stripe_start *= full_stripe_len;
+
+ /*
+ * For writes to RAID[56], allow a full stripeset across
+ * all disks. For other RAID types and for RAID[56]
+ * reads, just allow a single stripe (on a single disk).
+ */
+ if (op == BTRFS_MAP_WRITE) {
+ max_len = stripe_len * data_stripes -
+ (offset - raid56_full_stripe_start);
+ }
+ }
+ len = min_t(u64, em->len - offset, max_len);
+ } else {
+ len = em->len - offset;
+ }
+
+ io_geom->len = len;
+ io_geom->offset = offset;
+ io_geom->stripe_len = stripe_len;
+ io_geom->stripe_nr = stripe_nr;
+ io_geom->stripe_offset = stripe_offset;
+ io_geom->raid56_stripe_offset = raid56_full_stripe_start;
+
+ return 0;
+}
+
+static void set_io_stripe(struct btrfs_io_stripe *dst, const struct map_lookup *map,
+ u32 stripe_index, u64 stripe_offset, u64 stripe_nr)
+{
+ dst->dev = map->stripes[stripe_index].dev;
+ dst->physical = map->stripes[stripe_index].physical +
+ stripe_offset + stripe_nr * map->stripe_len;
+}
+
+static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
+ enum btrfs_map_op op, u64 logical, u64 *length,
+ struct btrfs_io_context **bioc_ret,
+ struct btrfs_io_stripe *smap,
+ int *mirror_num_ret, int need_raid_map)
+{
+ struct extent_map *em;
+ struct map_lookup *map;
+ u64 stripe_offset;
+ u64 stripe_nr;
+ u64 stripe_len;
+ u32 stripe_index;
+ int data_stripes;
+ int i;
+ int ret = 0;
+ int mirror_num = (mirror_num_ret ? *mirror_num_ret : 0);
+ int num_stripes;
+ int max_errors = 0;
+ int tgtdev_indexes = 0;
+ struct btrfs_io_context *bioc = NULL;
+ struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
+ int dev_replace_is_ongoing = 0;
+ int num_alloc_stripes;
+ int patch_the_first_stripe_for_dev_replace = 0;
+ u64 physical_to_patch_in_first_stripe = 0;
+ u64 raid56_full_stripe_start = (u64)-1;
+ struct btrfs_io_geometry geom;
+
+ ASSERT(bioc_ret);
+ ASSERT(op != BTRFS_MAP_DISCARD);
+
+ em = btrfs_get_chunk_map(fs_info, logical, *length);
+ ASSERT(!IS_ERR(em));
+
+ ret = btrfs_get_io_geometry(fs_info, em, op, logical, &geom);
+ if (ret < 0)
+ return ret;
+
+ map = em->map_lookup;
+
+ *length = geom.len;
+ stripe_len = geom.stripe_len;
+ stripe_nr = geom.stripe_nr;
+ stripe_offset = geom.stripe_offset;
+ raid56_full_stripe_start = geom.raid56_stripe_offset;
+ data_stripes = nr_data_stripes(map);
+
+ down_read(&dev_replace->rwsem);
+ dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
+ /*
+ * Hold the semaphore for read during the whole operation, write is
+ * requested at commit time but must wait.
+ */
+ if (!dev_replace_is_ongoing)
+ up_read(&dev_replace->rwsem);
+
+ if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
+ !need_full_stripe(op) && dev_replace->tgtdev != NULL) {
+ ret = get_extra_mirror_from_replace(fs_info, logical, *length,
+ dev_replace->srcdev->devid,
+ &mirror_num,
+ &physical_to_patch_in_first_stripe);
+ if (ret)
+ goto out;
+ else
+ patch_the_first_stripe_for_dev_replace = 1;
+ } else if (mirror_num > map->num_stripes) {
+ mirror_num = 0;
+ }
+
+ num_stripes = 1;
+ stripe_index = 0;
+ if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
+ stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
+ &stripe_index);
+ if (!need_full_stripe(op))
+ mirror_num = 1;
+ } else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) {
+ if (need_full_stripe(op))
+ num_stripes = map->num_stripes;
+ else if (mirror_num)
+ stripe_index = mirror_num - 1;
+ else {
+ stripe_index = find_live_mirror(fs_info, map, 0,
+ dev_replace_is_ongoing);
+ mirror_num = stripe_index + 1;
+ }
+
+ } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
+ if (need_full_stripe(op)) {
+ num_stripes = map->num_stripes;
+ } else if (mirror_num) {
+ stripe_index = mirror_num - 1;
+ } else {
+ mirror_num = 1;
+ }
+
+ } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
+ u32 factor = map->num_stripes / map->sub_stripes;
+
+ stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
+ stripe_index *= map->sub_stripes;
+
+ if (need_full_stripe(op))
+ num_stripes = map->sub_stripes;
+ else if (mirror_num)
+ stripe_index += mirror_num - 1;
+ else {
+ int old_stripe_index = stripe_index;
+ stripe_index = find_live_mirror(fs_info, map,
+ stripe_index,
+ dev_replace_is_ongoing);
+ mirror_num = stripe_index - old_stripe_index + 1;
+ }
+
+ } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+ ASSERT(map->stripe_len == BTRFS_STRIPE_LEN);
+ if (need_raid_map && (need_full_stripe(op) || mirror_num > 1)) {
+ /* push stripe_nr back to the start of the full stripe */
+ stripe_nr = div64_u64(raid56_full_stripe_start,
+ stripe_len * data_stripes);
+
+ /* RAID[56] write or recovery. Return all stripes */
+ num_stripes = map->num_stripes;
+ max_errors = btrfs_chunk_max_errors(map);
+
+ /* Return the length to the full stripe end */
+ *length = min(logical + *length,
+ raid56_full_stripe_start + em->start +
+ data_stripes * stripe_len) - logical;
+ stripe_index = 0;
+ stripe_offset = 0;
+ } else {
+ /*
+ * Mirror #0 or #1 means the original data block.
+ * Mirror #2 is RAID5 parity block.
+ * Mirror #3 is RAID6 Q block.
+ */
+ stripe_nr = div_u64_rem(stripe_nr,
+ data_stripes, &stripe_index);
+ if (mirror_num > 1)
+ stripe_index = data_stripes + mirror_num - 2;
+
+ /* We distribute the parity blocks across stripes */
+ div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
+ &stripe_index);
+ if (!need_full_stripe(op) && mirror_num <= 1)
+ mirror_num = 1;
+ }
+ } else {
+ /*
+ * after this, stripe_nr is the number of stripes on this
+ * device we have to walk to find the data, and stripe_index is
+ * the number of our device in the stripe array
+ */
+ stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
+ &stripe_index);
+ mirror_num = stripe_index + 1;
+ }
+ if (stripe_index >= map->num_stripes) {
+ btrfs_crit(fs_info,
+ "stripe index math went horribly wrong, got stripe_index=%u, num_stripes=%u",
+ stripe_index, map->num_stripes);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ num_alloc_stripes = num_stripes;
+ if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL) {
+ if (op == BTRFS_MAP_WRITE)
+ num_alloc_stripes <<= 1;
+ if (op == BTRFS_MAP_GET_READ_MIRRORS)
+ num_alloc_stripes++;
+ tgtdev_indexes = num_stripes;
+ }
+
+ /*
+ * If this I/O maps to a single device, try to return the device and
+ * physical block information on the stack instead of allocating an
+ * I/O context structure.
+ */
+ if (smap && num_alloc_stripes == 1 &&
+ !((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) && mirror_num > 1) &&
+ (!need_full_stripe(op) || !dev_replace_is_ongoing ||
+ !dev_replace->tgtdev)) {
+ if (patch_the_first_stripe_for_dev_replace) {
+ smap->dev = dev_replace->tgtdev;
+ smap->physical = physical_to_patch_in_first_stripe;
+ if (mirror_num_ret)
+ *mirror_num_ret = map->num_stripes + 1;
+ } else {
+ set_io_stripe(smap, map, stripe_index, stripe_offset,
+ stripe_nr);
+ if (mirror_num_ret)
+ *mirror_num_ret = mirror_num;
+ }
+ *bioc_ret = NULL;
+ ret = 0;
+ goto out;
+ }
+
+ bioc = alloc_btrfs_io_context(fs_info, num_alloc_stripes, tgtdev_indexes);
+ if (!bioc) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ for (i = 0; i < num_stripes; i++) {
+ set_io_stripe(&bioc->stripes[i], map, stripe_index, stripe_offset,
+ stripe_nr);
+ stripe_index++;
+ }
+
+ /* Build raid_map */
+ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK && need_raid_map &&
+ (need_full_stripe(op) || mirror_num > 1)) {
+ u64 tmp;
+ unsigned rot;
+
+ /* Work out the disk rotation on this stripe-set */
+ div_u64_rem(stripe_nr, num_stripes, &rot);
+
+ /* Fill in the logical address of each stripe */
+ tmp = stripe_nr * data_stripes;
+ for (i = 0; i < data_stripes; i++)
+ bioc->raid_map[(i + rot) % num_stripes] =
+ em->start + (tmp + i) * map->stripe_len;
+
+ bioc->raid_map[(i + rot) % map->num_stripes] = RAID5_P_STRIPE;
+ if (map->type & BTRFS_BLOCK_GROUP_RAID6)
+ bioc->raid_map[(i + rot + 1) % num_stripes] =
+ RAID6_Q_STRIPE;
+
+ sort_parity_stripes(bioc, num_stripes);
+ }
+
+ if (need_full_stripe(op))
+ max_errors = btrfs_chunk_max_errors(map);
+
+ if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
+ need_full_stripe(op)) {
+ handle_ops_on_dev_replace(op, &bioc, dev_replace, logical,
+ &num_stripes, &max_errors);
+ }
+
+ *bioc_ret = bioc;
+ bioc->map_type = map->type;
+ bioc->num_stripes = num_stripes;
+ bioc->max_errors = max_errors;
+ bioc->mirror_num = mirror_num;
+
+ /*
+ * this is the case that REQ_READ && dev_replace_is_ongoing &&
+ * mirror_num == num_stripes + 1 && dev_replace target drive is
+ * available as a mirror
+ */
+ if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
+ WARN_ON(num_stripes > 1);
+ bioc->stripes[0].dev = dev_replace->tgtdev;
+ bioc->stripes[0].physical = physical_to_patch_in_first_stripe;
+ bioc->mirror_num = map->num_stripes + 1;
+ }
+out:
+ if (dev_replace_is_ongoing) {
+ lockdep_assert_held(&dev_replace->rwsem);
+ /* Unlock and let waiting writers proceed */
+ up_read(&dev_replace->rwsem);
+ }
+ free_extent_map(em);
+ return ret;
+}
+
+int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
+ u64 logical, u64 *length,
+ struct btrfs_io_context **bioc_ret, int mirror_num)
+{
+ return __btrfs_map_block(fs_info, op, logical, length, bioc_ret,
+ NULL, &mirror_num, 0);
+}
+
+/* For Scrub/replace */
+int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
+ u64 logical, u64 *length,
+ struct btrfs_io_context **bioc_ret)
+{
+ return __btrfs_map_block(fs_info, op, logical, length, bioc_ret,
+ NULL, NULL, 1);
+}
+
+/*
+ * Initialize a btrfs_bio structure. This skips the embedded bio itself as it
+ * is already initialized by the block layer.
+ */
+static inline void btrfs_bio_init(struct btrfs_bio *bbio,
+ btrfs_bio_end_io_t end_io, void *private)
+{
+ memset(bbio, 0, offsetof(struct btrfs_bio, bio));
+ bbio->end_io = end_io;
+ bbio->private = private;
+}
+
+/*
+ * Allocate a btrfs_bio structure. The btrfs_bio is the main I/O container for
+ * btrfs, and is used for all I/O submitted through btrfs_submit_bio.
+ *
+ * Just like the underlying bio_alloc_bioset it will not fail as it is backed by
+ * a mempool.
+ */
+struct bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
+ btrfs_bio_end_io_t end_io, void *private)
+{
+ struct bio *bio;
+
+ bio = bio_alloc_bioset(NULL, nr_vecs, opf, GFP_NOFS, &btrfs_bioset);
+ btrfs_bio_init(btrfs_bio(bio), end_io, private);
+ return bio;
+}
+
+struct bio *btrfs_bio_clone_partial(struct bio *orig, u64 offset, u64 size,
+ btrfs_bio_end_io_t end_io, void *private)
+{
+ struct bio *bio;
+ struct btrfs_bio *bbio;
+
+ ASSERT(offset <= UINT_MAX && size <= UINT_MAX);
+
+ bio = bio_alloc_clone(orig->bi_bdev, orig, GFP_NOFS, &btrfs_bioset);
+ bbio = btrfs_bio(bio);
+ btrfs_bio_init(bbio, end_io, private);
+
+ bio_trim(bio, offset >> 9, size >> 9);
+ bbio->iter = bio->bi_iter;
+ return bio;
+}
+
+static void btrfs_log_dev_io_error(struct bio *bio, struct btrfs_device *dev)
+{
+ if (!dev || !dev->bdev)
+ return;
+ if (bio->bi_status != BLK_STS_IOERR && bio->bi_status != BLK_STS_TARGET)
+ return;
+
+ if (btrfs_op(bio) == BTRFS_MAP_WRITE)
+ btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS);
+ else if (!(bio->bi_opf & REQ_RAHEAD))
+ btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
+ if (bio->bi_opf & REQ_PREFLUSH)
+ btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_FLUSH_ERRS);
+}
+
+static struct workqueue_struct *btrfs_end_io_wq(struct btrfs_fs_info *fs_info,
+ struct bio *bio)
+{
+ if (bio->bi_opf & REQ_META)
+ return fs_info->endio_meta_workers;
+ return fs_info->endio_workers;
+}
+
+static void btrfs_end_bio_work(struct work_struct *work)
+{
+ struct btrfs_bio *bbio =
+ container_of(work, struct btrfs_bio, end_io_work);
+
+ bbio->end_io(bbio);
+}
+
+static void btrfs_simple_end_io(struct bio *bio)
+{
+ struct btrfs_fs_info *fs_info = bio->bi_private;
+ struct btrfs_bio *bbio = btrfs_bio(bio);
+
+ btrfs_bio_counter_dec(fs_info);
+
+ if (bio->bi_status)
+ btrfs_log_dev_io_error(bio, bbio->device);
+
+ if (bio_op(bio) == REQ_OP_READ) {
+ INIT_WORK(&bbio->end_io_work, btrfs_end_bio_work);
+ queue_work(btrfs_end_io_wq(fs_info, bio), &bbio->end_io_work);
+ } else {
+ bbio->end_io(bbio);
+ }
+}
+
+static void btrfs_raid56_end_io(struct bio *bio)
+{
+ struct btrfs_io_context *bioc = bio->bi_private;
+ struct btrfs_bio *bbio = btrfs_bio(bio);
+
+ btrfs_bio_counter_dec(bioc->fs_info);
+ bbio->mirror_num = bioc->mirror_num;
+ bbio->end_io(bbio);
+
+ btrfs_put_bioc(bioc);
+}
+
+static void btrfs_orig_write_end_io(struct bio *bio)
+{
+ struct btrfs_io_stripe *stripe = bio->bi_private;
+ struct btrfs_io_context *bioc = stripe->bioc;
+ struct btrfs_bio *bbio = btrfs_bio(bio);
+
+ btrfs_bio_counter_dec(bioc->fs_info);
+
+ if (bio->bi_status) {
+ atomic_inc(&bioc->error);
+ btrfs_log_dev_io_error(bio, stripe->dev);
+ }
+
+ /*
+ * Only send an error to the higher layers if it is beyond the tolerance
+ * threshold.
+ */
+ if (atomic_read(&bioc->error) > bioc->max_errors)
+ bio->bi_status = BLK_STS_IOERR;
+ else
+ bio->bi_status = BLK_STS_OK;
+
+ bbio->end_io(bbio);
+ btrfs_put_bioc(bioc);
+}
+
+static void btrfs_clone_write_end_io(struct bio *bio)
+{
+ struct btrfs_io_stripe *stripe = bio->bi_private;
+
+ if (bio->bi_status) {
+ atomic_inc(&stripe->bioc->error);
+ btrfs_log_dev_io_error(bio, stripe->dev);
+ }
+
+ /* Pass on control to the original bio this one was cloned from */
+ bio_endio(stripe->bioc->orig_bio);
+ bio_put(bio);
+}
+
+static void btrfs_submit_dev_bio(struct btrfs_device *dev, struct bio *bio)
+{
+ if (!dev || !dev->bdev ||
+ test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) ||
+ (btrfs_op(bio) == BTRFS_MAP_WRITE &&
+ !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))) {
+ bio_io_error(bio);
+ return;
+ }
+
+ bio_set_dev(bio, dev->bdev);
+
+ /*
+ * For zone append writing, bi_sector must point the beginning of the
+ * zone
+ */
+ if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
+ u64 physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
+
+ if (btrfs_dev_is_sequential(dev, physical)) {
+ u64 zone_start = round_down(physical,
+ dev->fs_info->zone_size);
+
+ bio->bi_iter.bi_sector = zone_start >> SECTOR_SHIFT;
+ } else {
+ bio->bi_opf &= ~REQ_OP_ZONE_APPEND;
+ bio->bi_opf |= REQ_OP_WRITE;
+ }
+ }
+ btrfs_debug_in_rcu(dev->fs_info,
+ "%s: rw %d 0x%x, sector=%llu, dev=%lu (%s id %llu), size=%u",
+ __func__, bio_op(bio), bio->bi_opf, bio->bi_iter.bi_sector,
+ (unsigned long)dev->bdev->bd_dev, rcu_str_deref(dev->name),
+ dev->devid, bio->bi_iter.bi_size);
+
+ btrfsic_check_bio(bio);
+ submit_bio(bio);
+}
+
+static void btrfs_submit_mirrored_bio(struct btrfs_io_context *bioc, int dev_nr)
+{
+ struct bio *orig_bio = bioc->orig_bio, *bio;
+
+ ASSERT(bio_op(orig_bio) != REQ_OP_READ);
+
+ /* Reuse the bio embedded into the btrfs_bio for the last mirror */
+ if (dev_nr == bioc->num_stripes - 1) {
+ bio = orig_bio;
+ bio->bi_end_io = btrfs_orig_write_end_io;
+ } else {
+ bio = bio_alloc_clone(NULL, orig_bio, GFP_NOFS, &fs_bio_set);
+ bio_inc_remaining(orig_bio);
+ bio->bi_end_io = btrfs_clone_write_end_io;
+ }
+
+ bio->bi_private = &bioc->stripes[dev_nr];
+ bio->bi_iter.bi_sector = bioc->stripes[dev_nr].physical >> SECTOR_SHIFT;
+ bioc->stripes[dev_nr].bioc = bioc;
+ btrfs_submit_dev_bio(bioc->stripes[dev_nr].dev, bio);
+}
+
+void btrfs_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, int mirror_num)
+{
+ u64 logical = bio->bi_iter.bi_sector << 9;
+ u64 length = bio->bi_iter.bi_size;
+ u64 map_length = length;
+ struct btrfs_io_context *bioc = NULL;
+ struct btrfs_io_stripe smap;
+ int ret;
+
+ btrfs_bio_counter_inc_blocked(fs_info);
+ ret = __btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length,
+ &bioc, &smap, &mirror_num, 1);
+ if (ret) {
+ btrfs_bio_counter_dec(fs_info);
+ btrfs_bio_end_io(btrfs_bio(bio), errno_to_blk_status(ret));
+ return;
+ }
+
+ if (map_length < length) {
+ btrfs_crit(fs_info,
+ "mapping failed logical %llu bio len %llu len %llu",
+ logical, length, map_length);
+ BUG();
+ }
+
+ if (!bioc) {
+ /* Single mirror read/write fast path */
+ btrfs_bio(bio)->mirror_num = mirror_num;
+ btrfs_bio(bio)->device = smap.dev;
+ bio->bi_iter.bi_sector = smap.physical >> SECTOR_SHIFT;
+ bio->bi_private = fs_info;
+ bio->bi_end_io = btrfs_simple_end_io;
+ btrfs_submit_dev_bio(smap.dev, bio);
+ } else if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+ /* Parity RAID write or read recovery */
+ bio->bi_private = bioc;
+ bio->bi_end_io = btrfs_raid56_end_io;
+ if (bio_op(bio) == REQ_OP_READ)
+ raid56_parity_recover(bio, bioc, mirror_num);
+ else
+ raid56_parity_write(bio, bioc);
+ } else {
+ /* Write to multiple mirrors */
+ int total_devs = bioc->num_stripes;
+ int dev_nr;
+
+ bioc->orig_bio = bio;
+ for (dev_nr = 0; dev_nr < total_devs; dev_nr++)
+ btrfs_submit_mirrored_bio(bioc, dev_nr);
+ }
+}
+
+static bool dev_args_match_fs_devices(const struct btrfs_dev_lookup_args *args,
+ const struct btrfs_fs_devices *fs_devices)
+{
+ if (args->fsid == NULL)
+ return true;
+ if (memcmp(fs_devices->metadata_uuid, args->fsid, BTRFS_FSID_SIZE) == 0)
+ return true;
+ return false;
+}
+
+static bool dev_args_match_device(const struct btrfs_dev_lookup_args *args,
+ const struct btrfs_device *device)
+{
+ if (args->missing) {
+ if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state) &&
+ !device->bdev)
+ return true;
+ return false;
+ }
+
+ if (device->devid != args->devid)
+ return false;
+ if (args->uuid && memcmp(device->uuid, args->uuid, BTRFS_UUID_SIZE) != 0)
+ return false;
+ return true;
+}
+
+/*
+ * Find a device specified by @devid or @uuid in the list of @fs_devices, or
+ * return NULL.
+ *
+ * If devid and uuid are both specified, the match must be exact, otherwise
+ * only devid is used.
+ */
+struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
+ const struct btrfs_dev_lookup_args *args)
+{
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *seed_devs;
+
+ if (dev_args_match_fs_devices(args, fs_devices)) {
+ list_for_each_entry(device, &fs_devices->devices, dev_list) {
+ if (dev_args_match_device(args, device))
+ return device;
+ }
+ }
+
+ list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
+ if (!dev_args_match_fs_devices(args, seed_devs))
+ continue;
+ list_for_each_entry(device, &seed_devs->devices, dev_list) {
+ if (dev_args_match_device(args, device))
+ return device;
+ }
+ }
+
+ return NULL;
+}
+
+static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices,
+ u64 devid, u8 *dev_uuid)
+{
+ struct btrfs_device *device;
+ unsigned int nofs_flag;
+
+ /*
+ * We call this under the chunk_mutex, so we want to use NOFS for this
+ * allocation, however we don't want to change btrfs_alloc_device() to
+ * always do NOFS because we use it in a lot of other GFP_KERNEL safe
+ * places.
+ */
+ nofs_flag = memalloc_nofs_save();
+ device = btrfs_alloc_device(NULL, &devid, dev_uuid);
+ memalloc_nofs_restore(nofs_flag);
+ if (IS_ERR(device))
+ return device;
+
+ list_add(&device->dev_list, &fs_devices->devices);
+ device->fs_devices = fs_devices;
+ fs_devices->num_devices++;
+
+ set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
+ fs_devices->missing_devices++;
+
+ return device;
+}
+
+/**
+ * btrfs_alloc_device - allocate struct btrfs_device
+ * @fs_info: used only for generating a new devid, can be NULL if
+ * devid is provided (i.e. @devid != NULL).
+ * @devid: a pointer to devid for this device. If NULL a new devid
+ * is generated.
+ * @uuid: a pointer to UUID for this device. If NULL a new UUID
+ * is generated.
+ *
+ * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
+ * on error. Returned struct is not linked onto any lists and must be
+ * destroyed with btrfs_free_device.
+ */
+struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
+ const u64 *devid,
+ const u8 *uuid)
+{
+ struct btrfs_device *dev;
+ u64 tmp;
+
+ if (WARN_ON(!devid && !fs_info))
+ return ERR_PTR(-EINVAL);
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&dev->dev_list);
+ INIT_LIST_HEAD(&dev->dev_alloc_list);
+ INIT_LIST_HEAD(&dev->post_commit_list);
+
+ atomic_set(&dev->dev_stats_ccnt, 0);
+ btrfs_device_data_ordered_init(dev);
+ extent_io_tree_init(fs_info, &dev->alloc_state,
+ IO_TREE_DEVICE_ALLOC_STATE, NULL);
+
+ if (devid)
+ tmp = *devid;
+ else {
+ int ret;
+
+ ret = find_next_devid(fs_info, &tmp);
+ if (ret) {
+ btrfs_free_device(dev);
+ return ERR_PTR(ret);
+ }
+ }
+ dev->devid = tmp;
+
+ if (uuid)
+ memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
+ else
+ generate_random_uuid(dev->uuid);
+
+ return dev;
+}
+
+static void btrfs_report_missing_device(struct btrfs_fs_info *fs_info,
+ u64 devid, u8 *uuid, bool error)
+{
+ if (error)
+ btrfs_err_rl(fs_info, "devid %llu uuid %pU is missing",
+ devid, uuid);
+ else
+ btrfs_warn_rl(fs_info, "devid %llu uuid %pU is missing",
+ devid, uuid);
+}
+
+u64 btrfs_calc_stripe_length(const struct extent_map *em)
+{
+ const struct map_lookup *map = em->map_lookup;
+ const int data_stripes = calc_data_stripes(map->type, map->num_stripes);
+
+ return div_u64(em->len, data_stripes);
+}
+
+#if BITS_PER_LONG == 32
+/*
+ * Due to page cache limit, metadata beyond BTRFS_32BIT_MAX_FILE_SIZE
+ * can't be accessed on 32bit systems.
+ *
+ * This function do mount time check to reject the fs if it already has
+ * metadata chunk beyond that limit.
+ */
+static int check_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 length, u64 type)
+{
+ if (!(type & BTRFS_BLOCK_GROUP_METADATA))
+ return 0;
+
+ if (logical + length < MAX_LFS_FILESIZE)
+ return 0;
+
+ btrfs_err_32bit_limit(fs_info);
+ return -EOVERFLOW;
+}
+
+/*
+ * This is to give early warning for any metadata chunk reaching
+ * BTRFS_32BIT_EARLY_WARN_THRESHOLD.
+ * Although we can still access the metadata, it's not going to be possible
+ * once the limit is reached.
+ */
+static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 length, u64 type)
+{
+ if (!(type & BTRFS_BLOCK_GROUP_METADATA))
+ return;
+
+ if (logical + length < BTRFS_32BIT_EARLY_WARN_THRESHOLD)
+ return;
+
+ btrfs_warn_32bit_limit(fs_info);
+}
+#endif
+
+static struct btrfs_device *handle_missing_device(struct btrfs_fs_info *fs_info,
+ u64 devid, u8 *uuid)
+{
+ struct btrfs_device *dev;
+
+ if (!btrfs_test_opt(fs_info, DEGRADED)) {
+ btrfs_report_missing_device(fs_info, devid, uuid, true);
+ return ERR_PTR(-ENOENT);
+ }
+
+ dev = add_missing_dev(fs_info->fs_devices, devid, uuid);
+ if (IS_ERR(dev)) {
+ btrfs_err(fs_info, "failed to init missing device %llu: %ld",
+ devid, PTR_ERR(dev));
+ return dev;
+ }
+ btrfs_report_missing_device(fs_info, devid, uuid, false);
+
+ return dev;
+}
+
+static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
+ struct btrfs_chunk *chunk)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct btrfs_fs_info *fs_info = leaf->fs_info;
+ struct extent_map_tree *map_tree = &fs_info->mapping_tree;
+ struct map_lookup *map;
+ struct extent_map *em;
+ u64 logical;
+ u64 length;
+ u64 devid;
+ u64 type;
+ u8 uuid[BTRFS_UUID_SIZE];
+ int index;
+ int num_stripes;
+ int ret;
+ int i;
+
+ logical = key->offset;
+ length = btrfs_chunk_length(leaf, chunk);
+ type = btrfs_chunk_type(leaf, chunk);
+ index = btrfs_bg_flags_to_raid_index(type);
+ num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
+
+#if BITS_PER_LONG == 32
+ ret = check_32bit_meta_chunk(fs_info, logical, length, type);
+ if (ret < 0)
+ return ret;
+ warn_32bit_meta_chunk(fs_info, logical, length, type);
+#endif
+
+ /*
+ * Only need to verify chunk item if we're reading from sys chunk array,
+ * as chunk item in tree block is already verified by tree-checker.
+ */
+ if (leaf->start == BTRFS_SUPER_INFO_OFFSET) {
+ ret = btrfs_check_chunk_valid(leaf, chunk, logical);
+ if (ret)
+ return ret;
+ }
+
+ read_lock(&map_tree->lock);
+ em = lookup_extent_mapping(map_tree, logical, 1);
+ read_unlock(&map_tree->lock);
+
+ /* already mapped? */
+ if (em && em->start <= logical && em->start + em->len > logical) {
+ free_extent_map(em);
+ return 0;
+ } else if (em) {
+ free_extent_map(em);
+ }
+
+ em = alloc_extent_map();
+ if (!em)
+ return -ENOMEM;
+ map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
+ if (!map) {
+ free_extent_map(em);
+ return -ENOMEM;
+ }
+
+ set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
+ em->map_lookup = map;
+ em->start = logical;
+ em->len = length;
+ em->orig_start = 0;
+ em->block_start = 0;
+ em->block_len = em->len;
+
+ map->num_stripes = num_stripes;
+ map->io_width = btrfs_chunk_io_width(leaf, chunk);
+ map->io_align = btrfs_chunk_io_align(leaf, chunk);
+ map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
+ map->type = type;
+ /*
+ * We can't use the sub_stripes value, as for profiles other than
+ * RAID10, they may have 0 as sub_stripes for filesystems created by
+ * older mkfs (<v5.4).
+ * In that case, it can cause divide-by-zero errors later.
+ * Since currently sub_stripes is fixed for each profile, let's
+ * use the trusted value instead.
+ */
+ map->sub_stripes = btrfs_raid_array[index].sub_stripes;
+ map->verified_stripes = 0;
+ em->orig_block_len = btrfs_calc_stripe_length(em);
+ for (i = 0; i < num_stripes; i++) {
+ map->stripes[i].physical =
+ btrfs_stripe_offset_nr(leaf, chunk, i);
+ devid = btrfs_stripe_devid_nr(leaf, chunk, i);
+ args.devid = devid;
+ read_extent_buffer(leaf, uuid, (unsigned long)
+ btrfs_stripe_dev_uuid_nr(chunk, i),
+ BTRFS_UUID_SIZE);
+ args.uuid = uuid;
+ map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, &args);
+ if (!map->stripes[i].dev) {
+ map->stripes[i].dev = handle_missing_device(fs_info,
+ devid, uuid);
+ if (IS_ERR(map->stripes[i].dev)) {
+ ret = PTR_ERR(map->stripes[i].dev);
+ free_extent_map(em);
+ return ret;
+ }
+ }
+
+ set_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
+ &(map->stripes[i].dev->dev_state));
+ }
+
+ write_lock(&map_tree->lock);
+ ret = add_extent_mapping(map_tree, em, 0);
+ write_unlock(&map_tree->lock);
+ if (ret < 0) {
+ btrfs_err(fs_info,
+ "failed to add chunk map, start=%llu len=%llu: %d",
+ em->start, em->len, ret);
+ }
+ free_extent_map(em);
+
+ return ret;
+}
+
+static void fill_device_from_item(struct extent_buffer *leaf,
+ struct btrfs_dev_item *dev_item,
+ struct btrfs_device *device)
+{
+ unsigned long ptr;
+
+ device->devid = btrfs_device_id(leaf, dev_item);
+ device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
+ device->total_bytes = device->disk_total_bytes;
+ device->commit_total_bytes = device->disk_total_bytes;
+ device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
+ device->commit_bytes_used = device->bytes_used;
+ device->type = btrfs_device_type(leaf, dev_item);
+ device->io_align = btrfs_device_io_align(leaf, dev_item);
+ device->io_width = btrfs_device_io_width(leaf, dev_item);
+ device->sector_size = btrfs_device_sector_size(leaf, dev_item);
+ WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
+ clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
+
+ ptr = btrfs_device_uuid(dev_item);
+ read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
+}
+
+static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info,
+ u8 *fsid)
+{
+ struct btrfs_fs_devices *fs_devices;
+ int ret;
+
+ lockdep_assert_held(&uuid_mutex);
+ ASSERT(fsid);
+
+ /* This will match only for multi-device seed fs */
+ list_for_each_entry(fs_devices, &fs_info->fs_devices->seed_list, seed_list)
+ if (!memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE))
+ return fs_devices;
+
+
+ fs_devices = find_fsid(fsid, NULL);
+ if (!fs_devices) {
+ if (!btrfs_test_opt(fs_info, DEGRADED))
+ return ERR_PTR(-ENOENT);
+
+ fs_devices = alloc_fs_devices(fsid, NULL);
+ if (IS_ERR(fs_devices))
+ return fs_devices;
+
+ fs_devices->seeding = true;
+ fs_devices->opened = 1;
+ return fs_devices;
+ }
+
+ /*
+ * Upon first call for a seed fs fsid, just create a private copy of the
+ * respective fs_devices and anchor it at fs_info->fs_devices->seed_list
+ */
+ fs_devices = clone_fs_devices(fs_devices);
+ if (IS_ERR(fs_devices))
+ return fs_devices;
+
+ ret = open_fs_devices(fs_devices, FMODE_READ, fs_info->bdev_holder);
+ if (ret) {
+ free_fs_devices(fs_devices);
+ return ERR_PTR(ret);
+ }
+
+ if (!fs_devices->seeding) {
+ close_fs_devices(fs_devices);
+ free_fs_devices(fs_devices);
+ return ERR_PTR(-EINVAL);
+ }
+
+ list_add(&fs_devices->seed_list, &fs_info->fs_devices->seed_list);
+
+ return fs_devices;
+}
+
+static int read_one_dev(struct extent_buffer *leaf,
+ struct btrfs_dev_item *dev_item)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct btrfs_fs_info *fs_info = leaf->fs_info;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ struct btrfs_device *device;
+ u64 devid;
+ int ret;
+ u8 fs_uuid[BTRFS_FSID_SIZE];
+ u8 dev_uuid[BTRFS_UUID_SIZE];
+
+ devid = btrfs_device_id(leaf, dev_item);
+ args.devid = devid;
+ read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
+ BTRFS_UUID_SIZE);
+ read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
+ BTRFS_FSID_SIZE);
+ args.uuid = dev_uuid;
+ args.fsid = fs_uuid;
+
+ if (memcmp(fs_uuid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE)) {
+ fs_devices = open_seed_devices(fs_info, fs_uuid);
+ if (IS_ERR(fs_devices))
+ return PTR_ERR(fs_devices);
+ }
+
+ device = btrfs_find_device(fs_info->fs_devices, &args);
+ if (!device) {
+ if (!btrfs_test_opt(fs_info, DEGRADED)) {
+ btrfs_report_missing_device(fs_info, devid,
+ dev_uuid, true);
+ return -ENOENT;
+ }
+
+ device = add_missing_dev(fs_devices, devid, dev_uuid);
+ if (IS_ERR(device)) {
+ btrfs_err(fs_info,
+ "failed to add missing dev %llu: %ld",
+ devid, PTR_ERR(device));
+ return PTR_ERR(device);
+ }
+ btrfs_report_missing_device(fs_info, devid, dev_uuid, false);
+ } else {
+ if (!device->bdev) {
+ if (!btrfs_test_opt(fs_info, DEGRADED)) {
+ btrfs_report_missing_device(fs_info,
+ devid, dev_uuid, true);
+ return -ENOENT;
+ }
+ btrfs_report_missing_device(fs_info, devid,
+ dev_uuid, false);
+ }
+
+ if (!device->bdev &&
+ !test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
+ /*
+ * this happens when a device that was properly setup
+ * in the device info lists suddenly goes bad.
+ * device->bdev is NULL, and so we have to set
+ * device->missing to one here
+ */
+ device->fs_devices->missing_devices++;
+ set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
+ }
+
+ /* Move the device to its own fs_devices */
+ if (device->fs_devices != fs_devices) {
+ ASSERT(test_bit(BTRFS_DEV_STATE_MISSING,
+ &device->dev_state));
+
+ list_move(&device->dev_list, &fs_devices->devices);
+ device->fs_devices->num_devices--;
+ fs_devices->num_devices++;
+
+ device->fs_devices->missing_devices--;
+ fs_devices->missing_devices++;
+
+ device->fs_devices = fs_devices;
+ }
+ }
+
+ if (device->fs_devices != fs_info->fs_devices) {
+ BUG_ON(test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state));
+ if (device->generation !=
+ btrfs_device_generation(leaf, dev_item))
+ return -EINVAL;
+ }
+
+ fill_device_from_item(leaf, dev_item, device);
+ if (device->bdev) {
+ u64 max_total_bytes = bdev_nr_bytes(device->bdev);
+
+ if (device->total_bytes > max_total_bytes) {
+ btrfs_err(fs_info,
+ "device total_bytes should be at most %llu but found %llu",
+ max_total_bytes, device->total_bytes);
+ return -EINVAL;
+ }
+ }
+ set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
+ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
+ !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
+ device->fs_devices->total_rw_bytes += device->total_bytes;
+ atomic64_add(device->total_bytes - device->bytes_used,
+ &fs_info->free_chunk_space);
+ }
+ ret = 0;
+ return ret;
+}
+
+int btrfs_read_sys_array(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_super_block *super_copy = fs_info->super_copy;
+ struct extent_buffer *sb;
+ struct btrfs_disk_key *disk_key;
+ struct btrfs_chunk *chunk;
+ u8 *array_ptr;
+ unsigned long sb_array_offset;
+ int ret = 0;
+ u32 num_stripes;
+ u32 array_size;
+ u32 len = 0;
+ u32 cur_offset;
+ u64 type;
+ struct btrfs_key key;
+
+ ASSERT(BTRFS_SUPER_INFO_SIZE <= fs_info->nodesize);
+
+ /*
+ * We allocated a dummy extent, just to use extent buffer accessors.
+ * There will be unused space after BTRFS_SUPER_INFO_SIZE, but
+ * that's fine, we will not go beyond system chunk array anyway.
+ */
+ sb = alloc_dummy_extent_buffer(fs_info, BTRFS_SUPER_INFO_OFFSET);
+ if (!sb)
+ return -ENOMEM;
+ set_extent_buffer_uptodate(sb);
+
+ write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
+ array_size = btrfs_super_sys_array_size(super_copy);
+
+ array_ptr = super_copy->sys_chunk_array;
+ sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
+ cur_offset = 0;
+
+ while (cur_offset < array_size) {
+ disk_key = (struct btrfs_disk_key *)array_ptr;
+ len = sizeof(*disk_key);
+ if (cur_offset + len > array_size)
+ goto out_short_read;
+
+ btrfs_disk_key_to_cpu(&key, disk_key);
+
+ array_ptr += len;
+ sb_array_offset += len;
+ cur_offset += len;
+
+ if (key.type != BTRFS_CHUNK_ITEM_KEY) {
+ btrfs_err(fs_info,
+ "unexpected item type %u in sys_array at offset %u",
+ (u32)key.type, cur_offset);
+ ret = -EIO;
+ break;
+ }
+
+ chunk = (struct btrfs_chunk *)sb_array_offset;
+ /*
+ * At least one btrfs_chunk with one stripe must be present,
+ * exact stripe count check comes afterwards
+ */
+ len = btrfs_chunk_item_size(1);
+ if (cur_offset + len > array_size)
+ goto out_short_read;
+
+ num_stripes = btrfs_chunk_num_stripes(sb, chunk);
+ if (!num_stripes) {
+ btrfs_err(fs_info,
+ "invalid number of stripes %u in sys_array at offset %u",
+ num_stripes, cur_offset);
+ ret = -EIO;
+ break;
+ }
+
+ type = btrfs_chunk_type(sb, chunk);
+ if ((type & BTRFS_BLOCK_GROUP_SYSTEM) == 0) {
+ btrfs_err(fs_info,
+ "invalid chunk type %llu in sys_array at offset %u",
+ type, cur_offset);
+ ret = -EIO;
+ break;
+ }
+
+ len = btrfs_chunk_item_size(num_stripes);
+ if (cur_offset + len > array_size)
+ goto out_short_read;
+
+ ret = read_one_chunk(&key, sb, chunk);
+ if (ret)
+ break;
+
+ array_ptr += len;
+ sb_array_offset += len;
+ cur_offset += len;
+ }
+ clear_extent_buffer_uptodate(sb);
+ free_extent_buffer_stale(sb);
+ return ret;
+
+out_short_read:
+ btrfs_err(fs_info, "sys_array too short to read %u bytes at offset %u",
+ len, cur_offset);
+ clear_extent_buffer_uptodate(sb);
+ free_extent_buffer_stale(sb);
+ return -EIO;
+}
+
+/*
+ * Check if all chunks in the fs are OK for read-write degraded mount
+ *
+ * If the @failing_dev is specified, it's accounted as missing.
+ *
+ * Return true if all chunks meet the minimal RW mount requirements.
+ * Return false if any chunk doesn't meet the minimal RW mount requirements.
+ */
+bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
+ struct btrfs_device *failing_dev)
+{
+ struct extent_map_tree *map_tree = &fs_info->mapping_tree;
+ struct extent_map *em;
+ u64 next_start = 0;
+ bool ret = true;
+
+ read_lock(&map_tree->lock);
+ em = lookup_extent_mapping(map_tree, 0, (u64)-1);
+ read_unlock(&map_tree->lock);
+ /* No chunk at all? Return false anyway */
+ if (!em) {
+ ret = false;
+ goto out;
+ }
+ while (em) {
+ struct map_lookup *map;
+ int missing = 0;
+ int max_tolerated;
+ int i;
+
+ map = em->map_lookup;
+ max_tolerated =
+ btrfs_get_num_tolerated_disk_barrier_failures(
+ map->type);
+ for (i = 0; i < map->num_stripes; i++) {
+ struct btrfs_device *dev = map->stripes[i].dev;
+
+ if (!dev || !dev->bdev ||
+ test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) ||
+ dev->last_flush_error)
+ missing++;
+ else if (failing_dev && failing_dev == dev)
+ missing++;
+ }
+ if (missing > max_tolerated) {
+ if (!failing_dev)
+ btrfs_warn(fs_info,
+ "chunk %llu missing %d devices, max tolerance is %d for writable mount",
+ em->start, missing, max_tolerated);
+ free_extent_map(em);
+ ret = false;
+ goto out;
+ }
+ next_start = extent_map_end(em);
+ free_extent_map(em);
+
+ read_lock(&map_tree->lock);
+ em = lookup_extent_mapping(map_tree, next_start,
+ (u64)(-1) - next_start);
+ read_unlock(&map_tree->lock);
+ }
+out:
+ return ret;
+}
+
+static void readahead_tree_node_children(struct extent_buffer *node)
+{
+ int i;
+ const int nr_items = btrfs_header_nritems(node);
+
+ for (i = 0; i < nr_items; i++)
+ btrfs_readahead_node_child(node, i);
+}
+
+int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *root = fs_info->chunk_root;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ int ret;
+ int slot;
+ int iter_ret = 0;
+ u64 total_dev = 0;
+ u64 last_ra_node = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ /*
+ * uuid_mutex is needed only if we are mounting a sprout FS
+ * otherwise we don't need it.
+ */
+ mutex_lock(&uuid_mutex);
+
+ /*
+ * It is possible for mount and umount to race in such a way that
+ * we execute this code path, but open_fs_devices failed to clear
+ * total_rw_bytes. We certainly want it cleared before reading the
+ * device items, so clear it here.
+ */
+ fs_info->fs_devices->total_rw_bytes = 0;
+
+ /*
+ * Lockdep complains about possible circular locking dependency between
+ * a disk's open_mutex (struct gendisk.open_mutex), the rw semaphores
+ * used for freeze procection of a fs (struct super_block.s_writers),
+ * which we take when starting a transaction, and extent buffers of the
+ * chunk tree if we call read_one_dev() while holding a lock on an
+ * extent buffer of the chunk tree. Since we are mounting the filesystem
+ * and at this point there can't be any concurrent task modifying the
+ * chunk tree, to keep it simple, just skip locking on the chunk tree.
+ */
+ ASSERT(!test_bit(BTRFS_FS_OPEN, &fs_info->flags));
+ path->skip_locking = 1;
+
+ /*
+ * Read all device items, and then all the chunk items. All
+ * device items are found before any chunk item (their object id
+ * is smaller than the lowest possible object id for a chunk
+ * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
+ */
+ key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+ key.offset = 0;
+ key.type = 0;
+ btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) {
+ struct extent_buffer *node = path->nodes[1];
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+
+ if (node) {
+ if (last_ra_node != node->start) {
+ readahead_tree_node_children(node);
+ last_ra_node = node->start;
+ }
+ }
+ if (found_key.type == BTRFS_DEV_ITEM_KEY) {
+ struct btrfs_dev_item *dev_item;
+ dev_item = btrfs_item_ptr(leaf, slot,
+ struct btrfs_dev_item);
+ ret = read_one_dev(leaf, dev_item);
+ if (ret)
+ goto error;
+ total_dev++;
+ } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
+ struct btrfs_chunk *chunk;
+
+ /*
+ * We are only called at mount time, so no need to take
+ * fs_info->chunk_mutex. Plus, to avoid lockdep warnings,
+ * we always lock first fs_info->chunk_mutex before
+ * acquiring any locks on the chunk tree. This is a
+ * requirement for chunk allocation, see the comment on
+ * top of btrfs_chunk_alloc() for details.
+ */
+ chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
+ ret = read_one_chunk(&found_key, leaf, chunk);
+ if (ret)
+ goto error;
+ }
+ }
+ /* Catch error found during iteration */
+ if (iter_ret < 0) {
+ ret = iter_ret;
+ goto error;
+ }
+
+ /*
+ * After loading chunk tree, we've got all device information,
+ * do another round of validation checks.
+ */
+ if (total_dev != fs_info->fs_devices->total_devices) {
+ btrfs_warn(fs_info,
+"super block num_devices %llu mismatch with DEV_ITEM count %llu, will be repaired on next transaction commit",
+ btrfs_super_num_devices(fs_info->super_copy),
+ total_dev);
+ fs_info->fs_devices->total_devices = total_dev;
+ btrfs_set_super_num_devices(fs_info->super_copy, total_dev);
+ }
+ if (btrfs_super_total_bytes(fs_info->super_copy) <
+ fs_info->fs_devices->total_rw_bytes) {
+ btrfs_err(fs_info,
+ "super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu",
+ btrfs_super_total_bytes(fs_info->super_copy),
+ fs_info->fs_devices->total_rw_bytes);
+ ret = -EINVAL;
+ goto error;
+ }
+ ret = 0;
+error:
+ mutex_unlock(&uuid_mutex);
+
+ btrfs_free_path(path);
+ return ret;
+}
+
+int btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
+ struct btrfs_device *device;
+ int ret = 0;
+
+ fs_devices->fs_info = fs_info;
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ list_for_each_entry(device, &fs_devices->devices, dev_list)
+ device->fs_info = fs_info;
+
+ list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
+ list_for_each_entry(device, &seed_devs->devices, dev_list) {
+ device->fs_info = fs_info;
+ ret = btrfs_get_dev_zone_info(device, false);
+ if (ret)
+ break;
+ }
+
+ seed_devs->fs_info = fs_info;
+ }
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ return ret;
+}
+
+static u64 btrfs_dev_stats_value(const struct extent_buffer *eb,
+ const struct btrfs_dev_stats_item *ptr,
+ int index)
+{
+ u64 val;
+
+ read_extent_buffer(eb, &val,
+ offsetof(struct btrfs_dev_stats_item, values) +
+ ((unsigned long)ptr) + (index * sizeof(u64)),
+ sizeof(val));
+ return val;
+}
+
+static void btrfs_set_dev_stats_value(struct extent_buffer *eb,
+ struct btrfs_dev_stats_item *ptr,
+ int index, u64 val)
+{
+ write_extent_buffer(eb, &val,
+ offsetof(struct btrfs_dev_stats_item, values) +
+ ((unsigned long)ptr) + (index * sizeof(u64)),
+ sizeof(val));
+}
+
+static int btrfs_device_init_dev_stats(struct btrfs_device *device,
+ struct btrfs_path *path)
+{
+ struct btrfs_dev_stats_item *ptr;
+ struct extent_buffer *eb;
+ struct btrfs_key key;
+ int item_size;
+ int i, ret, slot;
+
+ if (!device->fs_info->dev_root)
+ return 0;
+
+ key.objectid = BTRFS_DEV_STATS_OBJECTID;
+ key.type = BTRFS_PERSISTENT_ITEM_KEY;
+ key.offset = device->devid;
+ ret = btrfs_search_slot(NULL, device->fs_info->dev_root, &key, path, 0, 0);
+ if (ret) {
+ for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
+ btrfs_dev_stat_set(device, i, 0);
+ device->dev_stats_valid = 1;
+ btrfs_release_path(path);
+ return ret < 0 ? ret : 0;
+ }
+ slot = path->slots[0];
+ eb = path->nodes[0];
+ item_size = btrfs_item_size(eb, slot);
+
+ ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_stats_item);
+
+ for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
+ if (item_size >= (1 + i) * sizeof(__le64))
+ btrfs_dev_stat_set(device, i,
+ btrfs_dev_stats_value(eb, ptr, i));
+ else
+ btrfs_dev_stat_set(device, i, 0);
+ }
+
+ device->dev_stats_valid = 1;
+ btrfs_dev_stat_print_on_load(device);
+ btrfs_release_path(path);
+
+ return 0;
+}
+
+int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
+ struct btrfs_device *device;
+ struct btrfs_path *path = NULL;
+ int ret = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ list_for_each_entry(device, &fs_devices->devices, dev_list) {
+ ret = btrfs_device_init_dev_stats(device, path);
+ if (ret)
+ goto out;
+ }
+ list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
+ list_for_each_entry(device, &seed_devs->devices, dev_list) {
+ ret = btrfs_device_init_dev_stats(device, path);
+ if (ret)
+ goto out;
+ }
+ }
+out:
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int update_dev_stat_item(struct btrfs_trans_handle *trans,
+ struct btrfs_device *device)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_root *dev_root = fs_info->dev_root;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct extent_buffer *eb;
+ struct btrfs_dev_stats_item *ptr;
+ int ret;
+ int i;
+
+ key.objectid = BTRFS_DEV_STATS_OBJECTID;
+ key.type = BTRFS_PERSISTENT_ITEM_KEY;
+ key.offset = device->devid;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
+ if (ret < 0) {
+ btrfs_warn_in_rcu(fs_info,
+ "error %d while searching for dev_stats item for device %s",
+ ret, rcu_str_deref(device->name));
+ goto out;
+ }
+
+ if (ret == 0 &&
+ btrfs_item_size(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
+ /* need to delete old one and insert a new one */
+ ret = btrfs_del_item(trans, dev_root, path);
+ if (ret != 0) {
+ btrfs_warn_in_rcu(fs_info,
+ "delete too small dev_stats item for device %s failed %d",
+ rcu_str_deref(device->name), ret);
+ goto out;
+ }
+ ret = 1;
+ }
+
+ if (ret == 1) {
+ /* need to insert a new item */
+ btrfs_release_path(path);
+ ret = btrfs_insert_empty_item(trans, dev_root, path,
+ &key, sizeof(*ptr));
+ if (ret < 0) {
+ btrfs_warn_in_rcu(fs_info,
+ "insert dev_stats item for device %s failed %d",
+ rcu_str_deref(device->name), ret);
+ goto out;
+ }
+ }
+
+ eb = path->nodes[0];
+ ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
+ for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
+ btrfs_set_dev_stats_value(eb, ptr, i,
+ btrfs_dev_stat_read(device, i));
+ btrfs_mark_buffer_dirty(eb);
+
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * called from commit_transaction. Writes all changed device stats to disk.
+ */
+int btrfs_run_dev_stats(struct btrfs_trans_handle *trans)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ struct btrfs_device *device;
+ int stats_cnt;
+ int ret = 0;
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ list_for_each_entry(device, &fs_devices->devices, dev_list) {
+ stats_cnt = atomic_read(&device->dev_stats_ccnt);
+ if (!device->dev_stats_valid || stats_cnt == 0)
+ continue;
+
+
+ /*
+ * There is a LOAD-LOAD control dependency between the value of
+ * dev_stats_ccnt and updating the on-disk values which requires
+ * reading the in-memory counters. Such control dependencies
+ * require explicit read memory barriers.
+ *
+ * This memory barriers pairs with smp_mb__before_atomic in
+ * btrfs_dev_stat_inc/btrfs_dev_stat_set and with the full
+ * barrier implied by atomic_xchg in
+ * btrfs_dev_stats_read_and_reset
+ */
+ smp_rmb();
+
+ ret = update_dev_stat_item(trans, device);
+ if (!ret)
+ atomic_sub(stats_cnt, &device->dev_stats_ccnt);
+ }
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ return ret;
+}
+
+void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
+{
+ btrfs_dev_stat_inc(dev, index);
+
+ if (!dev->dev_stats_valid)
+ return;
+ btrfs_err_rl_in_rcu(dev->fs_info,
+ "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
+ rcu_str_deref(dev->name),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
+}
+
+static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
+{
+ int i;
+
+ for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
+ if (btrfs_dev_stat_read(dev, i) != 0)
+ break;
+ if (i == BTRFS_DEV_STAT_VALUES_MAX)
+ return; /* all values == 0, suppress message */
+
+ btrfs_info_in_rcu(dev->fs_info,
+ "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
+ rcu_str_deref(dev->name),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
+ btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
+}
+
+int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
+ struct btrfs_ioctl_get_dev_stats *stats)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct btrfs_device *dev;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ int i;
+
+ mutex_lock(&fs_devices->device_list_mutex);
+ args.devid = stats->devid;
+ dev = btrfs_find_device(fs_info->fs_devices, &args);
+ mutex_unlock(&fs_devices->device_list_mutex);
+
+ if (!dev) {
+ btrfs_warn(fs_info, "get dev_stats failed, device not found");
+ return -ENODEV;
+ } else if (!dev->dev_stats_valid) {
+ btrfs_warn(fs_info, "get dev_stats failed, not yet valid");
+ return -ENODEV;
+ } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
+ for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
+ if (stats->nr_items > i)
+ stats->values[i] =
+ btrfs_dev_stat_read_and_reset(dev, i);
+ else
+ btrfs_dev_stat_set(dev, i, 0);
+ }
+ btrfs_info(fs_info, "device stats zeroed by %s (%d)",
+ current->comm, task_pid_nr(current));
+ } else {
+ for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
+ if (stats->nr_items > i)
+ stats->values[i] = btrfs_dev_stat_read(dev, i);
+ }
+ if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
+ stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
+ return 0;
+}
+
+/*
+ * Update the size and bytes used for each device where it changed. This is
+ * delayed since we would otherwise get errors while writing out the
+ * superblocks.
+ *
+ * Must be invoked during transaction commit.
+ */
+void btrfs_commit_device_sizes(struct btrfs_transaction *trans)
+{
+ struct btrfs_device *curr, *next;
+
+ ASSERT(trans->state == TRANS_STATE_COMMIT_DOING);
+
+ if (list_empty(&trans->dev_update_list))
+ return;
+
+ /*
+ * We don't need the device_list_mutex here. This list is owned by the
+ * transaction and the transaction must complete before the device is
+ * released.
+ */
+ mutex_lock(&trans->fs_info->chunk_mutex);
+ list_for_each_entry_safe(curr, next, &trans->dev_update_list,
+ post_commit_list) {
+ list_del_init(&curr->post_commit_list);
+ curr->commit_total_bytes = curr->disk_total_bytes;
+ curr->commit_bytes_used = curr->bytes_used;
+ }
+ mutex_unlock(&trans->fs_info->chunk_mutex);
+}
+
+/*
+ * Multiplicity factor for simple profiles: DUP, RAID1-like and RAID10.
+ */
+int btrfs_bg_type_to_factor(u64 flags)
+{
+ const int index = btrfs_bg_flags_to_raid_index(flags);
+
+ return btrfs_raid_array[index].ncopies;
+}
+
+
+
+static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
+ u64 chunk_offset, u64 devid,
+ u64 physical_offset, u64 physical_len)
+{
+ struct btrfs_dev_lookup_args args = { .devid = devid };
+ struct extent_map_tree *em_tree = &fs_info->mapping_tree;
+ struct extent_map *em;
+ struct map_lookup *map;
+ struct btrfs_device *dev;
+ u64 stripe_len;
+ bool found = false;
+ int ret = 0;
+ int i;
+
+ read_lock(&em_tree->lock);
+ em = lookup_extent_mapping(em_tree, chunk_offset, 1);
+ read_unlock(&em_tree->lock);
+
+ if (!em) {
+ btrfs_err(fs_info,
+"dev extent physical offset %llu on devid %llu doesn't have corresponding chunk",
+ physical_offset, devid);
+ ret = -EUCLEAN;
+ goto out;
+ }
+
+ map = em->map_lookup;
+ stripe_len = btrfs_calc_stripe_length(em);
+ if (physical_len != stripe_len) {
+ btrfs_err(fs_info,
+"dev extent physical offset %llu on devid %llu length doesn't match chunk %llu, have %llu expect %llu",
+ physical_offset, devid, em->start, physical_len,
+ stripe_len);
+ ret = -EUCLEAN;
+ goto out;
+ }
+
+ /*
+ * Very old mkfs.btrfs (before v4.1) will not respect the reserved
+ * space. Although kernel can handle it without problem, better to warn
+ * the users.
+ */
+ if (physical_offset < BTRFS_DEVICE_RANGE_RESERVED)
+ btrfs_warn(fs_info,
+ "devid %llu physical %llu len %llu inside the reserved space",
+ devid, physical_offset, physical_len);
+
+ for (i = 0; i < map->num_stripes; i++) {
+ if (map->stripes[i].dev->devid == devid &&
+ map->stripes[i].physical == physical_offset) {
+ found = true;
+ if (map->verified_stripes >= map->num_stripes) {
+ btrfs_err(fs_info,
+ "too many dev extents for chunk %llu found",
+ em->start);
+ ret = -EUCLEAN;
+ goto out;
+ }
+ map->verified_stripes++;
+ break;
+ }
+ }
+ if (!found) {
+ btrfs_err(fs_info,
+ "dev extent physical offset %llu devid %llu has no corresponding chunk",
+ physical_offset, devid);
+ ret = -EUCLEAN;
+ }
+
+ /* Make sure no dev extent is beyond device boundary */
+ dev = btrfs_find_device(fs_info->fs_devices, &args);
+ if (!dev) {
+ btrfs_err(fs_info, "failed to find devid %llu", devid);
+ ret = -EUCLEAN;
+ goto out;
+ }
+
+ if (physical_offset + physical_len > dev->disk_total_bytes) {
+ btrfs_err(fs_info,
+"dev extent devid %llu physical offset %llu len %llu is beyond device boundary %llu",
+ devid, physical_offset, physical_len,
+ dev->disk_total_bytes);
+ ret = -EUCLEAN;
+ goto out;
+ }
+
+ if (dev->zone_info) {
+ u64 zone_size = dev->zone_info->zone_size;
+
+ if (!IS_ALIGNED(physical_offset, zone_size) ||
+ !IS_ALIGNED(physical_len, zone_size)) {
+ btrfs_err(fs_info,
+"zoned: dev extent devid %llu physical offset %llu len %llu is not aligned to device zone",
+ devid, physical_offset, physical_len);
+ ret = -EUCLEAN;
+ goto out;
+ }
+ }
+
+out:
+ free_extent_map(em);
+ return ret;
+}
+
+static int verify_chunk_dev_extent_mapping(struct btrfs_fs_info *fs_info)
+{
+ struct extent_map_tree *em_tree = &fs_info->mapping_tree;
+ struct extent_map *em;
+ struct rb_node *node;
+ int ret = 0;
+
+ read_lock(&em_tree->lock);
+ for (node = rb_first_cached(&em_tree->map); node; node = rb_next(node)) {
+ em = rb_entry(node, struct extent_map, rb_node);
+ if (em->map_lookup->num_stripes !=
+ em->map_lookup->verified_stripes) {
+ btrfs_err(fs_info,
+ "chunk %llu has missing dev extent, have %d expect %d",
+ em->start, em->map_lookup->verified_stripes,
+ em->map_lookup->num_stripes);
+ ret = -EUCLEAN;
+ goto out;
+ }
+ }
+out:
+ read_unlock(&em_tree->lock);
+ return ret;
+}
+
+/*
+ * Ensure that all dev extents are mapped to correct chunk, otherwise
+ * later chunk allocation/free would cause unexpected behavior.
+ *
+ * NOTE: This will iterate through the whole device tree, which should be of
+ * the same size level as the chunk tree. This slightly increases mount time.
+ */
+int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_path *path;
+ struct btrfs_root *root = fs_info->dev_root;
+ struct btrfs_key key;
+ u64 prev_devid = 0;
+ u64 prev_dev_ext_end = 0;
+ int ret = 0;
+
+ /*
+ * We don't have a dev_root because we mounted with ignorebadroots and
+ * failed to load the root, so we want to skip the verification in this
+ * case for sure.
+ *
+ * However if the dev root is fine, but the tree itself is corrupted
+ * we'd still fail to mount. This verification is only to make sure
+ * writes can happen safely, so instead just bypass this check
+ * completely in the case of IGNOREBADROOTS.
+ */
+ if (btrfs_test_opt(fs_info, IGNOREBADROOTS))
+ return 0;
+
+ key.objectid = 1;
+ key.type = BTRFS_DEV_EXTENT_KEY;
+ key.offset = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ path->reada = READA_FORWARD;
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+
+ if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret < 0)
+ goto out;
+ /* No dev extents at all? Not good */
+ if (ret > 0) {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ }
+ while (1) {
+ struct extent_buffer *leaf = path->nodes[0];
+ struct btrfs_dev_extent *dext;
+ int slot = path->slots[0];
+ u64 chunk_offset;
+ u64 physical_offset;
+ u64 physical_len;
+ u64 devid;
+
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+ if (key.type != BTRFS_DEV_EXTENT_KEY)
+ break;
+ devid = key.objectid;
+ physical_offset = key.offset;
+
+ dext = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
+ chunk_offset = btrfs_dev_extent_chunk_offset(leaf, dext);
+ physical_len = btrfs_dev_extent_length(leaf, dext);
+
+ /* Check if this dev extent overlaps with the previous one */
+ if (devid == prev_devid && physical_offset < prev_dev_ext_end) {
+ btrfs_err(fs_info,
+"dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu",
+ devid, physical_offset, prev_dev_ext_end);
+ ret = -EUCLEAN;
+ goto out;
+ }
+
+ ret = verify_one_dev_extent(fs_info, chunk_offset, devid,
+ physical_offset, physical_len);
+ if (ret < 0)
+ goto out;
+ prev_devid = devid;
+ prev_dev_ext_end = physical_offset + physical_len;
+
+ ret = btrfs_next_item(root, path);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ ret = 0;
+ break;
+ }
+ }
+
+ /* Ensure all chunks have corresponding dev extents */
+ ret = verify_chunk_dev_extent_mapping(fs_info);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * Check whether the given block group or device is pinned by any inode being
+ * used as a swapfile.
+ */
+bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr)
+{
+ struct btrfs_swapfile_pin *sp;
+ struct rb_node *node;
+
+ spin_lock(&fs_info->swapfile_pins_lock);
+ node = fs_info->swapfile_pins.rb_node;
+ while (node) {
+ sp = rb_entry(node, struct btrfs_swapfile_pin, node);
+ if (ptr < sp->ptr)
+ node = node->rb_left;
+ else if (ptr > sp->ptr)
+ node = node->rb_right;
+ else
+ break;
+ }
+ spin_unlock(&fs_info->swapfile_pins_lock);
+ return node != NULL;
+}
+
+static int relocating_repair_kthread(void *data)
+{
+ struct btrfs_block_group *cache = data;
+ struct btrfs_fs_info *fs_info = cache->fs_info;
+ u64 target;
+ int ret = 0;
+
+ target = cache->start;
+ btrfs_put_block_group(cache);
+
+ sb_start_write(fs_info->sb);
+ if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
+ btrfs_info(fs_info,
+ "zoned: skip relocating block group %llu to repair: EBUSY",
+ target);
+ sb_end_write(fs_info->sb);
+ return -EBUSY;
+ }
+
+ mutex_lock(&fs_info->reclaim_bgs_lock);
+
+ /* Ensure block group still exists */
+ cache = btrfs_lookup_block_group(fs_info, target);
+ if (!cache)
+ goto out;
+
+ if (!test_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags))
+ goto out;
+
+ ret = btrfs_may_alloc_data_chunk(fs_info, target);
+ if (ret < 0)
+ goto out;
+
+ btrfs_info(fs_info,
+ "zoned: relocating block group %llu to repair IO failure",
+ target);
+ ret = btrfs_relocate_chunk(fs_info, target);
+
+out:
+ if (cache)
+ btrfs_put_block_group(cache);
+ mutex_unlock(&fs_info->reclaim_bgs_lock);
+ btrfs_exclop_finish(fs_info);
+ sb_end_write(fs_info->sb);
+
+ return ret;
+}
+
+bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical)
+{
+ struct btrfs_block_group *cache;
+
+ if (!btrfs_is_zoned(fs_info))
+ return false;
+
+ /* Do not attempt to repair in degraded state */
+ if (btrfs_test_opt(fs_info, DEGRADED))
+ return true;
+
+ cache = btrfs_lookup_block_group(fs_info, logical);
+ if (!cache)
+ return true;
+
+ if (test_and_set_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags)) {
+ btrfs_put_block_group(cache);
+ return true;
+ }
+
+ kthread_run(relocating_repair_kthread, cache,
+ "btrfs-relocating-repair");
+
+ return true;
+}
+
+int __init btrfs_bioset_init(void)
+{
+ if (bioset_init(&btrfs_bioset, BIO_POOL_SIZE,
+ offsetof(struct btrfs_bio, bio),
+ BIOSET_NEED_BVECS))
+ return -ENOMEM;
+ return 0;
+}
+
+void __cold btrfs_bioset_exit(void)
+{
+ bioset_exit(&btrfs_bioset);
+}