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diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2007 Oracle. All rights reserved.
+ */
+
+#ifndef BTRFS_VOLUMES_H
+#define BTRFS_VOLUMES_H
+
+#include <linux/sort.h>
+#include <linux/btrfs.h>
+#include "async-thread.h"
+#include "messages.h"
+#include "tree-checker.h"
+#include "rcu-string.h"
+
+#define BTRFS_MAX_DATA_CHUNK_SIZE (10ULL * SZ_1G)
+
+extern struct mutex uuid_mutex;
+
+#define BTRFS_STRIPE_LEN SZ_64K
+#define BTRFS_STRIPE_LEN_SHIFT (16)
+#define BTRFS_STRIPE_LEN_MASK (BTRFS_STRIPE_LEN - 1)
+
+static_assert(const_ilog2(BTRFS_STRIPE_LEN) == BTRFS_STRIPE_LEN_SHIFT);
+
+/* Used by sanity check for btrfs_raid_types. */
+#define const_ffs(n) (__builtin_ctzll(n) + 1)
+
+/*
+ * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires
+ * RAID0 always to be the lowest profile bit.
+ * Although it's part of on-disk format and should never change, do extra
+ * compile-time sanity checks.
+ */
+static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <
+ const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));
+static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) >
+ ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK));
+
+/* ilog2() can handle both constants and variables */
+#define BTRFS_BG_FLAG_TO_INDEX(profile) \
+ ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1))
+
+enum btrfs_raid_types {
+ /* SINGLE is the special one as it doesn't have on-disk bit. */
+ BTRFS_RAID_SINGLE = 0,
+
+ BTRFS_RAID_RAID0 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0),
+ BTRFS_RAID_RAID1 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1),
+ BTRFS_RAID_DUP = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP),
+ BTRFS_RAID_RAID10 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10),
+ BTRFS_RAID_RAID5 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5),
+ BTRFS_RAID_RAID6 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6),
+ BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3),
+ BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4),
+
+ BTRFS_NR_RAID_TYPES
+};
+
+/*
+ * Use sequence counter to get consistent device stat data on
+ * 32-bit processors.
+ */
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#include <linux/seqlock.h>
+#define __BTRFS_NEED_DEVICE_DATA_ORDERED
+#define btrfs_device_data_ordered_init(device) \
+ seqcount_init(&device->data_seqcount)
+#else
+#define btrfs_device_data_ordered_init(device) do { } while (0)
+#endif
+
+#define BTRFS_DEV_STATE_WRITEABLE (0)
+#define BTRFS_DEV_STATE_IN_FS_METADATA (1)
+#define BTRFS_DEV_STATE_MISSING (2)
+#define BTRFS_DEV_STATE_REPLACE_TGT (3)
+#define BTRFS_DEV_STATE_FLUSH_SENT (4)
+#define BTRFS_DEV_STATE_NO_READA (5)
+
+struct btrfs_zoned_device_info;
+
+struct btrfs_device {
+ struct list_head dev_list; /* device_list_mutex */
+ struct list_head dev_alloc_list; /* chunk mutex */
+ struct list_head post_commit_list; /* chunk mutex */
+ struct btrfs_fs_devices *fs_devices;
+ struct btrfs_fs_info *fs_info;
+
+ struct rcu_string __rcu *name;
+
+ u64 generation;
+
+ struct block_device *bdev;
+
+ struct btrfs_zoned_device_info *zone_info;
+
+ /* block device holder for blkdev_get/put */
+ void *holder;
+
+ /*
+ * Device's major-minor number. Must be set even if the device is not
+ * opened (bdev == NULL), unless the device is missing.
+ */
+ dev_t devt;
+ unsigned long dev_state;
+ blk_status_t last_flush_error;
+
+#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
+ seqcount_t data_seqcount;
+#endif
+
+ /* the internal btrfs device id */
+ u64 devid;
+
+ /* size of the device in memory */
+ u64 total_bytes;
+
+ /* size of the device on disk */
+ u64 disk_total_bytes;
+
+ /* bytes used */
+ u64 bytes_used;
+
+ /* optimal io alignment for this device */
+ u32 io_align;
+
+ /* optimal io width for this device */
+ u32 io_width;
+ /* type and info about this device */
+ u64 type;
+
+ /* minimal io size for this device */
+ u32 sector_size;
+
+ /* physical drive uuid (or lvm uuid) */
+ u8 uuid[BTRFS_UUID_SIZE];
+
+ /*
+ * size of the device on the current transaction
+ *
+ * This variant is update when committing the transaction,
+ * and protected by chunk mutex
+ */
+ u64 commit_total_bytes;
+
+ /* bytes used on the current transaction */
+ u64 commit_bytes_used;
+
+ /* Bio used for flushing device barriers */
+ struct bio flush_bio;
+ struct completion flush_wait;
+
+ /* per-device scrub information */
+ struct scrub_ctx *scrub_ctx;
+
+ /* disk I/O failure stats. For detailed description refer to
+ * enum btrfs_dev_stat_values in ioctl.h */
+ int dev_stats_valid;
+
+ /* Counter to record the change of device stats */
+ atomic_t dev_stats_ccnt;
+ atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
+
+ struct extent_io_tree alloc_state;
+
+ struct completion kobj_unregister;
+ /* For sysfs/FSID/devinfo/devid/ */
+ struct kobject devid_kobj;
+
+ /* Bandwidth limit for scrub, in bytes */
+ u64 scrub_speed_max;
+};
+
+/*
+ * Block group or device which contains an active swapfile. Used for preventing
+ * unsafe operations while a swapfile is active.
+ *
+ * These are sorted on (ptr, inode) (note that a block group or device can
+ * contain more than one swapfile). We compare the pointer values because we
+ * don't actually care what the object is, we just need a quick check whether
+ * the object exists in the rbtree.
+ */
+struct btrfs_swapfile_pin {
+ struct rb_node node;
+ void *ptr;
+ struct inode *inode;
+ /*
+ * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr
+ * points to a struct btrfs_device.
+ */
+ bool is_block_group;
+ /*
+ * Only used when 'is_block_group' is true and it is the number of
+ * extents used by a swapfile for this block group ('ptr' field).
+ */
+ int bg_extent_count;
+};
+
+/*
+ * If we read those variants at the context of their own lock, we needn't
+ * use the following helpers, reading them directly is safe.
+ */
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#define BTRFS_DEVICE_GETSET_FUNCS(name) \
+static inline u64 \
+btrfs_device_get_##name(const struct btrfs_device *dev) \
+{ \
+ u64 size; \
+ unsigned int seq; \
+ \
+ do { \
+ seq = read_seqcount_begin(&dev->data_seqcount); \
+ size = dev->name; \
+ } while (read_seqcount_retry(&dev->data_seqcount, seq)); \
+ return size; \
+} \
+ \
+static inline void \
+btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
+{ \
+ preempt_disable(); \
+ write_seqcount_begin(&dev->data_seqcount); \
+ dev->name = size; \
+ write_seqcount_end(&dev->data_seqcount); \
+ preempt_enable(); \
+}
+#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
+#define BTRFS_DEVICE_GETSET_FUNCS(name) \
+static inline u64 \
+btrfs_device_get_##name(const struct btrfs_device *dev) \
+{ \
+ u64 size; \
+ \
+ preempt_disable(); \
+ size = dev->name; \
+ preempt_enable(); \
+ return size; \
+} \
+ \
+static inline void \
+btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
+{ \
+ preempt_disable(); \
+ dev->name = size; \
+ preempt_enable(); \
+}
+#else
+#define BTRFS_DEVICE_GETSET_FUNCS(name) \
+static inline u64 \
+btrfs_device_get_##name(const struct btrfs_device *dev) \
+{ \
+ return dev->name; \
+} \
+ \
+static inline void \
+btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
+{ \
+ dev->name = size; \
+}
+#endif
+
+BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
+BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
+BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
+
+enum btrfs_chunk_allocation_policy {
+ BTRFS_CHUNK_ALLOC_REGULAR,
+ BTRFS_CHUNK_ALLOC_ZONED,
+};
+
+/*
+ * Read policies for mirrored block group profiles, read picks the stripe based
+ * on these policies.
+ */
+enum btrfs_read_policy {
+ /* Use process PID to choose the stripe */
+ BTRFS_READ_POLICY_PID,
+ BTRFS_NR_READ_POLICY,
+};
+
+struct btrfs_fs_devices {
+ u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
+
+ /*
+ * UUID written into the btree blocks:
+ *
+ * - If metadata_uuid != fsid then super block must have
+ * BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag set.
+ *
+ * - Following shall be true at all times:
+ * - metadata_uuid == btrfs_header::fsid
+ * - metadata_uuid == btrfs_dev_item::fsid
+ */
+ u8 metadata_uuid[BTRFS_FSID_SIZE];
+
+ struct list_head fs_list;
+
+ /*
+ * Number of devices under this fsid including missing and
+ * replace-target device and excludes seed devices.
+ */
+ u64 num_devices;
+
+ /*
+ * The number of devices that successfully opened, including
+ * replace-target, excludes seed devices.
+ */
+ u64 open_devices;
+
+ /* The number of devices that are under the chunk allocation list. */
+ u64 rw_devices;
+
+ /* Count of missing devices under this fsid excluding seed device. */
+ u64 missing_devices;
+ u64 total_rw_bytes;
+
+ /*
+ * Count of devices from btrfs_super_block::num_devices for this fsid,
+ * which includes the seed device, excludes the transient replace-target
+ * device.
+ */
+ u64 total_devices;
+
+ /* Highest generation number of seen devices */
+ u64 latest_generation;
+
+ /*
+ * The mount device or a device with highest generation after removal
+ * or replace.
+ */
+ struct btrfs_device *latest_dev;
+
+ /*
+ * All of the devices in the filesystem, protected by a mutex so we can
+ * safely walk it to write out the super blocks without worrying about
+ * adding/removing by the multi-device code. Scrubbing super block can
+ * kick off supers writing by holding this mutex lock.
+ */
+ struct mutex device_list_mutex;
+
+ /* List of all devices, protected by device_list_mutex */
+ struct list_head devices;
+
+ /* Devices which can satisfy space allocation. Protected by * chunk_mutex. */
+ struct list_head alloc_list;
+
+ struct list_head seed_list;
+
+ /* Count fs-devices opened. */
+ int opened;
+
+ /* Set when we find or add a device that doesn't have the nonrot flag set. */
+ bool rotating;
+ /* Devices support TRIM/discard commands. */
+ bool discardable;
+ bool fsid_change;
+ /* The filesystem is a seed filesystem. */
+ bool seeding;
+
+ struct btrfs_fs_info *fs_info;
+ /* sysfs kobjects */
+ struct kobject fsid_kobj;
+ struct kobject *devices_kobj;
+ struct kobject *devinfo_kobj;
+ struct completion kobj_unregister;
+
+ enum btrfs_chunk_allocation_policy chunk_alloc_policy;
+
+ /* Policy used to read the mirrored stripes. */
+ enum btrfs_read_policy read_policy;
+};
+
+#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info) \
+ - sizeof(struct btrfs_chunk)) \
+ / sizeof(struct btrfs_stripe) + 1)
+
+#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
+ - 2 * sizeof(struct btrfs_disk_key) \
+ - 2 * sizeof(struct btrfs_chunk)) \
+ / sizeof(struct btrfs_stripe) + 1)
+
+struct btrfs_io_stripe {
+ struct btrfs_device *dev;
+ union {
+ /* Block mapping */
+ u64 physical;
+ /* For the endio handler */
+ struct btrfs_io_context *bioc;
+ };
+};
+
+struct btrfs_discard_stripe {
+ struct btrfs_device *dev;
+ u64 physical;
+ u64 length;
+};
+
+/*
+ * Context for IO subsmission for device stripe.
+ *
+ * - Track the unfinished mirrors for mirror based profiles
+ * Mirror based profiles are SINGLE/DUP/RAID1/RAID10.
+ *
+ * - Contain the logical -> physical mapping info
+ * Used by submit_stripe_bio() for mapping logical bio
+ * into physical device address.
+ *
+ * - Contain device replace info
+ * Used by handle_ops_on_dev_replace() to copy logical bios
+ * into the new device.
+ *
+ * - Contain RAID56 full stripe logical bytenrs
+ */
+struct btrfs_io_context {
+ refcount_t refs;
+ struct btrfs_fs_info *fs_info;
+ u64 map_type; /* get from map_lookup->type */
+ struct bio *orig_bio;
+ atomic_t error;
+ u16 max_errors;
+
+ /*
+ * The total number of stripes, including the extra duplicated
+ * stripe for replace.
+ */
+ u16 num_stripes;
+
+ /*
+ * The mirror_num of this bioc.
+ *
+ * This is for reads which use 0 as mirror_num, thus we should return a
+ * valid mirror_num (>0) for the reader.
+ */
+ u16 mirror_num;
+
+ /*
+ * The following two members are for dev-replace case only.
+ *
+ * @replace_nr_stripes: Number of duplicated stripes which need to be
+ * written to replace target.
+ * Should be <= 2 (2 for DUP, otherwise <= 1).
+ * @replace_stripe_src: The array indicates where the duplicated stripes
+ * are from.
+ *
+ * The @replace_stripe_src[] array is mostly for RAID56 cases.
+ * As non-RAID56 stripes share the same contents of the mapped range,
+ * thus no need to bother where the duplicated ones are from.
+ *
+ * But for RAID56 case, all stripes contain different contents, thus
+ * we need a way to know the mapping.
+ *
+ * There is an example for the two members, using a RAID5 write:
+ *
+ * num_stripes: 4 (3 + 1 duplicated write)
+ * stripes[0]: dev = devid 1, physical = X
+ * stripes[1]: dev = devid 2, physical = Y
+ * stripes[2]: dev = devid 3, physical = Z
+ * stripes[3]: dev = devid 0, physical = Y
+ *
+ * replace_nr_stripes = 1
+ * replace_stripe_src = 1 <- Means stripes[1] is involved in replace.
+ * The duplicated stripe index would be
+ * (@num_stripes - 1).
+ *
+ * Note, that we can still have cases replace_nr_stripes = 2 for DUP.
+ * In that case, all stripes share the same content, thus we don't
+ * need to bother @replace_stripe_src value at all.
+ */
+ u16 replace_nr_stripes;
+ s16 replace_stripe_src;
+ /*
+ * Logical bytenr of the full stripe start, only for RAID56 cases.
+ *
+ * When this value is set to other than (u64)-1, the stripes[] should
+ * follow this pattern:
+ *
+ * (real_stripes = num_stripes - replace_nr_stripes)
+ * (data_stripes = (is_raid6) ? (real_stripes - 2) : (real_stripes - 1))
+ *
+ * stripes[0]: The first data stripe
+ * stripes[1]: The second data stripe
+ * ...
+ * stripes[data_stripes - 1]: The last data stripe
+ * stripes[data_stripes]: The P stripe
+ * stripes[data_stripes + 1]: The Q stripe (only for RAID6).
+ */
+ u64 full_stripe_logical;
+ struct btrfs_io_stripe stripes[];
+};
+
+struct btrfs_device_info {
+ struct btrfs_device *dev;
+ u64 dev_offset;
+ u64 max_avail;
+ u64 total_avail;
+};
+
+struct btrfs_raid_attr {
+ u8 sub_stripes; /* sub_stripes info for map */
+ u8 dev_stripes; /* stripes per dev */
+ u8 devs_max; /* max devs to use */
+ u8 devs_min; /* min devs needed */
+ u8 tolerated_failures; /* max tolerated fail devs */
+ u8 devs_increment; /* ndevs has to be a multiple of this */
+ u8 ncopies; /* how many copies to data has */
+ u8 nparity; /* number of stripes worth of bytes to store
+ * parity information */
+ u8 mindev_error; /* error code if min devs requisite is unmet */
+ const char raid_name[8]; /* name of the raid */
+ u64 bg_flag; /* block group flag of the raid */
+};
+
+extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
+
+struct map_lookup {
+ u64 type;
+ int io_align;
+ int io_width;
+ int num_stripes;
+ int sub_stripes;
+ int verified_stripes; /* For mount time dev extent verification */
+ struct btrfs_io_stripe stripes[];
+};
+
+#define map_lookup_size(n) (sizeof(struct map_lookup) + \
+ (sizeof(struct btrfs_io_stripe) * (n)))
+
+struct btrfs_balance_args;
+struct btrfs_balance_progress;
+struct btrfs_balance_control {
+ struct btrfs_balance_args data;
+ struct btrfs_balance_args meta;
+ struct btrfs_balance_args sys;
+
+ u64 flags;
+
+ struct btrfs_balance_progress stat;
+};
+
+/*
+ * Search for a given device by the set parameters
+ */
+struct btrfs_dev_lookup_args {
+ u64 devid;
+ u8 *uuid;
+ u8 *fsid;
+ bool missing;
+};
+
+/* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */
+#define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }
+
+#define BTRFS_DEV_LOOKUP_ARGS(name) \
+ struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT
+
+enum btrfs_map_op {
+ BTRFS_MAP_READ,
+ BTRFS_MAP_WRITE,
+ BTRFS_MAP_GET_READ_MIRRORS,
+};
+
+static inline enum btrfs_map_op btrfs_op(struct bio *bio)
+{
+ switch (bio_op(bio)) {
+ case REQ_OP_WRITE:
+ case REQ_OP_ZONE_APPEND:
+ return BTRFS_MAP_WRITE;
+ default:
+ WARN_ON_ONCE(1);
+ fallthrough;
+ case REQ_OP_READ:
+ return BTRFS_MAP_READ;
+ }
+}
+
+static inline unsigned long btrfs_chunk_item_size(int num_stripes)
+{
+ ASSERT(num_stripes);
+ return sizeof(struct btrfs_chunk) +
+ sizeof(struct btrfs_stripe) * (num_stripes - 1);
+}
+
+/*
+ * Do the type safe converstion from stripe_nr to offset inside the chunk.
+ *
+ * @stripe_nr is u32, with left shift it can overflow u32 for chunks larger
+ * than 4G. This does the proper type cast to avoid overflow.
+ */
+static inline u64 btrfs_stripe_nr_to_offset(u32 stripe_nr)
+{
+ return (u64)stripe_nr << BTRFS_STRIPE_LEN_SHIFT;
+}
+
+void btrfs_get_bioc(struct btrfs_io_context *bioc);
+void btrfs_put_bioc(struct btrfs_io_context *bioc);
+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);
+int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,
+ struct btrfs_io_stripe *smap, u64 logical,
+ u32 length, int mirror_num);
+struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 *length_ret,
+ u32 *num_stripes);
+int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
+int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
+struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
+ u64 type);
+void btrfs_mapping_tree_free(struct extent_map_tree *tree);
+int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
+ blk_mode_t flags, void *holder);
+struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags);
+int btrfs_forget_devices(dev_t devt);
+void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
+void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);
+void btrfs_assign_next_active_device(struct btrfs_device *device,
+ struct btrfs_device *this_dev);
+struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
+ u64 devid,
+ const char *devpath);
+int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
+ struct btrfs_dev_lookup_args *args,
+ const char *path);
+struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
+ const u64 *devid, const u8 *uuid,
+ const char *path);
+void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
+int btrfs_rm_device(struct btrfs_fs_info *fs_info,
+ struct btrfs_dev_lookup_args *args,
+ struct block_device **bdev, void **holder);
+void __exit btrfs_cleanup_fs_uuids(void);
+int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
+int btrfs_grow_device(struct btrfs_trans_handle *trans,
+ struct btrfs_device *device, u64 new_size);
+struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
+ const struct btrfs_dev_lookup_args *args);
+int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
+int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
+int btrfs_balance(struct btrfs_fs_info *fs_info,
+ struct btrfs_balance_control *bctl,
+ struct btrfs_ioctl_balance_args *bargs);
+void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
+int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
+int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
+int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
+int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);
+int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
+int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
+int btrfs_uuid_scan_kthread(void *data);
+bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);
+void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
+int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
+ struct btrfs_ioctl_get_dev_stats *stats);
+int btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
+int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
+int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);
+void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
+void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
+void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
+int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 len);
+unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
+ u64 logical);
+u64 btrfs_calc_stripe_length(const struct extent_map *em);
+int btrfs_nr_parity_stripes(u64 type);
+int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
+ struct btrfs_block_group *bg);
+int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
+struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 length);
+void btrfs_release_disk_super(struct btrfs_super_block *super);
+
+static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
+ int index)
+{
+ atomic_inc(dev->dev_stat_values + index);
+ /*
+ * This memory barrier orders stores updating statistics before stores
+ * updating dev_stats_ccnt.
+ *
+ * It pairs with smp_rmb() in btrfs_run_dev_stats().
+ */
+ smp_mb__before_atomic();
+ atomic_inc(&dev->dev_stats_ccnt);
+}
+
+static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
+ int index)
+{
+ return atomic_read(dev->dev_stat_values + index);
+}
+
+static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
+ int index)
+{
+ int ret;
+
+ ret = atomic_xchg(dev->dev_stat_values + index, 0);
+ /*
+ * atomic_xchg implies a full memory barriers as per atomic_t.txt:
+ * - RMW operations that have a return value are fully ordered;
+ *
+ * This implicit memory barriers is paired with the smp_rmb in
+ * btrfs_run_dev_stats
+ */
+ atomic_inc(&dev->dev_stats_ccnt);
+ return ret;
+}
+
+static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
+ int index, unsigned long val)
+{
+ atomic_set(dev->dev_stat_values + index, val);
+ /*
+ * This memory barrier orders stores updating statistics before stores
+ * updating dev_stats_ccnt.
+ *
+ * It pairs with smp_rmb() in btrfs_run_dev_stats().
+ */
+ smp_mb__before_atomic();
+ atomic_inc(&dev->dev_stats_ccnt);
+}
+
+static inline const char *btrfs_dev_name(const struct btrfs_device *device)
+{
+ if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
+ return "<missing disk>";
+ else
+ return rcu_str_deref(device->name);
+}
+
+void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
+
+struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
+bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
+ struct btrfs_device *failing_dev);
+void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
+ struct block_device *bdev,
+ const char *device_path);
+
+enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);
+int btrfs_bg_type_to_factor(u64 flags);
+const char *btrfs_bg_type_to_raid_name(u64 flags);
+int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
+bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
+
+bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
+u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb);
+
+#endif