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-rw-r--r--fs/btrfs/ioctl.c4741
1 files changed, 4741 insertions, 0 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
new file mode 100644
index 0000000000..908215928d
--- /dev/null
+++ b/fs/btrfs/ioctl.c
@@ -0,0 +1,4741 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2007 Oracle. All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/bio.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/fsnotify.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+#include <linux/time.h>
+#include <linux/string.h>
+#include <linux/backing-dev.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/writeback.h>
+#include <linux/compat.h>
+#include <linux/security.h>
+#include <linux/xattr.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include <linux/uuid.h>
+#include <linux/btrfs.h>
+#include <linux/uaccess.h>
+#include <linux/iversion.h>
+#include <linux/fileattr.h>
+#include <linux/fsverity.h>
+#include <linux/sched/xacct.h>
+#include "ctree.h"
+#include "disk-io.h"
+#include "export.h"
+#include "transaction.h"
+#include "btrfs_inode.h"
+#include "print-tree.h"
+#include "volumes.h"
+#include "locking.h"
+#include "backref.h"
+#include "rcu-string.h"
+#include "send.h"
+#include "dev-replace.h"
+#include "props.h"
+#include "sysfs.h"
+#include "qgroup.h"
+#include "tree-log.h"
+#include "compression.h"
+#include "space-info.h"
+#include "delalloc-space.h"
+#include "block-group.h"
+#include "subpage.h"
+#include "fs.h"
+#include "accessors.h"
+#include "extent-tree.h"
+#include "root-tree.h"
+#include "defrag.h"
+#include "dir-item.h"
+#include "uuid-tree.h"
+#include "ioctl.h"
+#include "file.h"
+#include "scrub.h"
+#include "super.h"
+
+#ifdef CONFIG_64BIT
+/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
+ * structures are incorrect, as the timespec structure from userspace
+ * is 4 bytes too small. We define these alternatives here to teach
+ * the kernel about the 32-bit struct packing.
+ */
+struct btrfs_ioctl_timespec_32 {
+ __u64 sec;
+ __u32 nsec;
+} __attribute__ ((__packed__));
+
+struct btrfs_ioctl_received_subvol_args_32 {
+ char uuid[BTRFS_UUID_SIZE]; /* in */
+ __u64 stransid; /* in */
+ __u64 rtransid; /* out */
+ struct btrfs_ioctl_timespec_32 stime; /* in */
+ struct btrfs_ioctl_timespec_32 rtime; /* out */
+ __u64 flags; /* in */
+ __u64 reserved[16]; /* in */
+} __attribute__ ((__packed__));
+
+#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
+ struct btrfs_ioctl_received_subvol_args_32)
+#endif
+
+#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
+struct btrfs_ioctl_send_args_32 {
+ __s64 send_fd; /* in */
+ __u64 clone_sources_count; /* in */
+ compat_uptr_t clone_sources; /* in */
+ __u64 parent_root; /* in */
+ __u64 flags; /* in */
+ __u32 version; /* in */
+ __u8 reserved[28]; /* in */
+} __attribute__ ((__packed__));
+
+#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
+ struct btrfs_ioctl_send_args_32)
+
+struct btrfs_ioctl_encoded_io_args_32 {
+ compat_uptr_t iov;
+ compat_ulong_t iovcnt;
+ __s64 offset;
+ __u64 flags;
+ __u64 len;
+ __u64 unencoded_len;
+ __u64 unencoded_offset;
+ __u32 compression;
+ __u32 encryption;
+ __u8 reserved[64];
+};
+
+#define BTRFS_IOC_ENCODED_READ_32 _IOR(BTRFS_IOCTL_MAGIC, 64, \
+ struct btrfs_ioctl_encoded_io_args_32)
+#define BTRFS_IOC_ENCODED_WRITE_32 _IOW(BTRFS_IOCTL_MAGIC, 64, \
+ struct btrfs_ioctl_encoded_io_args_32)
+#endif
+
+/* Mask out flags that are inappropriate for the given type of inode. */
+static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
+ unsigned int flags)
+{
+ if (S_ISDIR(inode->i_mode))
+ return flags;
+ else if (S_ISREG(inode->i_mode))
+ return flags & ~FS_DIRSYNC_FL;
+ else
+ return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
+}
+
+/*
+ * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
+ * ioctl.
+ */
+static unsigned int btrfs_inode_flags_to_fsflags(struct btrfs_inode *binode)
+{
+ unsigned int iflags = 0;
+ u32 flags = binode->flags;
+ u32 ro_flags = binode->ro_flags;
+
+ if (flags & BTRFS_INODE_SYNC)
+ iflags |= FS_SYNC_FL;
+ if (flags & BTRFS_INODE_IMMUTABLE)
+ iflags |= FS_IMMUTABLE_FL;
+ if (flags & BTRFS_INODE_APPEND)
+ iflags |= FS_APPEND_FL;
+ if (flags & BTRFS_INODE_NODUMP)
+ iflags |= FS_NODUMP_FL;
+ if (flags & BTRFS_INODE_NOATIME)
+ iflags |= FS_NOATIME_FL;
+ if (flags & BTRFS_INODE_DIRSYNC)
+ iflags |= FS_DIRSYNC_FL;
+ if (flags & BTRFS_INODE_NODATACOW)
+ iflags |= FS_NOCOW_FL;
+ if (ro_flags & BTRFS_INODE_RO_VERITY)
+ iflags |= FS_VERITY_FL;
+
+ if (flags & BTRFS_INODE_NOCOMPRESS)
+ iflags |= FS_NOCOMP_FL;
+ else if (flags & BTRFS_INODE_COMPRESS)
+ iflags |= FS_COMPR_FL;
+
+ return iflags;
+}
+
+/*
+ * Update inode->i_flags based on the btrfs internal flags.
+ */
+void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
+{
+ struct btrfs_inode *binode = BTRFS_I(inode);
+ unsigned int new_fl = 0;
+
+ if (binode->flags & BTRFS_INODE_SYNC)
+ new_fl |= S_SYNC;
+ if (binode->flags & BTRFS_INODE_IMMUTABLE)
+ new_fl |= S_IMMUTABLE;
+ if (binode->flags & BTRFS_INODE_APPEND)
+ new_fl |= S_APPEND;
+ if (binode->flags & BTRFS_INODE_NOATIME)
+ new_fl |= S_NOATIME;
+ if (binode->flags & BTRFS_INODE_DIRSYNC)
+ new_fl |= S_DIRSYNC;
+ if (binode->ro_flags & BTRFS_INODE_RO_VERITY)
+ new_fl |= S_VERITY;
+
+ set_mask_bits(&inode->i_flags,
+ S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |
+ S_VERITY, new_fl);
+}
+
+/*
+ * Check if @flags are a supported and valid set of FS_*_FL flags and that
+ * the old and new flags are not conflicting
+ */
+static int check_fsflags(unsigned int old_flags, unsigned int flags)
+{
+ if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
+ FS_NOATIME_FL | FS_NODUMP_FL | \
+ FS_SYNC_FL | FS_DIRSYNC_FL | \
+ FS_NOCOMP_FL | FS_COMPR_FL |
+ FS_NOCOW_FL))
+ return -EOPNOTSUPP;
+
+ /* COMPR and NOCOMP on new/old are valid */
+ if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
+ return -EINVAL;
+
+ if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
+ return -EINVAL;
+
+ /* NOCOW and compression options are mutually exclusive */
+ if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
+ return -EINVAL;
+ if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,
+ unsigned int flags)
+{
+ if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))
+ return -EPERM;
+
+ return 0;
+}
+
+/*
+ * Set flags/xflags from the internal inode flags. The remaining items of
+ * fsxattr are zeroed.
+ */
+int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
+{
+ struct btrfs_inode *binode = BTRFS_I(d_inode(dentry));
+
+ fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode));
+ return 0;
+}
+
+int btrfs_fileattr_set(struct mnt_idmap *idmap,
+ struct dentry *dentry, struct fileattr *fa)
+{
+ struct inode *inode = d_inode(dentry);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_inode *binode = BTRFS_I(inode);
+ struct btrfs_root *root = binode->root;
+ struct btrfs_trans_handle *trans;
+ unsigned int fsflags, old_fsflags;
+ int ret;
+ const char *comp = NULL;
+ u32 binode_flags;
+
+ if (btrfs_root_readonly(root))
+ return -EROFS;
+
+ if (fileattr_has_fsx(fa))
+ return -EOPNOTSUPP;
+
+ fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags);
+ old_fsflags = btrfs_inode_flags_to_fsflags(binode);
+ ret = check_fsflags(old_fsflags, fsflags);
+ if (ret)
+ return ret;
+
+ ret = check_fsflags_compatible(fs_info, fsflags);
+ if (ret)
+ return ret;
+
+ binode_flags = binode->flags;
+ if (fsflags & FS_SYNC_FL)
+ binode_flags |= BTRFS_INODE_SYNC;
+ else
+ binode_flags &= ~BTRFS_INODE_SYNC;
+ if (fsflags & FS_IMMUTABLE_FL)
+ binode_flags |= BTRFS_INODE_IMMUTABLE;
+ else
+ binode_flags &= ~BTRFS_INODE_IMMUTABLE;
+ if (fsflags & FS_APPEND_FL)
+ binode_flags |= BTRFS_INODE_APPEND;
+ else
+ binode_flags &= ~BTRFS_INODE_APPEND;
+ if (fsflags & FS_NODUMP_FL)
+ binode_flags |= BTRFS_INODE_NODUMP;
+ else
+ binode_flags &= ~BTRFS_INODE_NODUMP;
+ if (fsflags & FS_NOATIME_FL)
+ binode_flags |= BTRFS_INODE_NOATIME;
+ else
+ binode_flags &= ~BTRFS_INODE_NOATIME;
+
+ /* If coming from FS_IOC_FSSETXATTR then skip unconverted flags */
+ if (!fa->flags_valid) {
+ /* 1 item for the inode */
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+ goto update_flags;
+ }
+
+ if (fsflags & FS_DIRSYNC_FL)
+ binode_flags |= BTRFS_INODE_DIRSYNC;
+ else
+ binode_flags &= ~BTRFS_INODE_DIRSYNC;
+ if (fsflags & FS_NOCOW_FL) {
+ if (S_ISREG(inode->i_mode)) {
+ /*
+ * It's safe to turn csums off here, no extents exist.
+ * Otherwise we want the flag to reflect the real COW
+ * status of the file and will not set it.
+ */
+ if (inode->i_size == 0)
+ binode_flags |= BTRFS_INODE_NODATACOW |
+ BTRFS_INODE_NODATASUM;
+ } else {
+ binode_flags |= BTRFS_INODE_NODATACOW;
+ }
+ } else {
+ /*
+ * Revert back under same assumptions as above
+ */
+ if (S_ISREG(inode->i_mode)) {
+ if (inode->i_size == 0)
+ binode_flags &= ~(BTRFS_INODE_NODATACOW |
+ BTRFS_INODE_NODATASUM);
+ } else {
+ binode_flags &= ~BTRFS_INODE_NODATACOW;
+ }
+ }
+
+ /*
+ * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
+ * flag may be changed automatically if compression code won't make
+ * things smaller.
+ */
+ if (fsflags & FS_NOCOMP_FL) {
+ binode_flags &= ~BTRFS_INODE_COMPRESS;
+ binode_flags |= BTRFS_INODE_NOCOMPRESS;
+ } else if (fsflags & FS_COMPR_FL) {
+
+ if (IS_SWAPFILE(inode))
+ return -ETXTBSY;
+
+ binode_flags |= BTRFS_INODE_COMPRESS;
+ binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
+
+ comp = btrfs_compress_type2str(fs_info->compress_type);
+ if (!comp || comp[0] == 0)
+ comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
+ } else {
+ binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
+ }
+
+ /*
+ * 1 for inode item
+ * 2 for properties
+ */
+ trans = btrfs_start_transaction(root, 3);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
+ if (comp) {
+ ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
+ strlen(comp), 0);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out_end_trans;
+ }
+ } else {
+ ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
+ 0, 0);
+ if (ret && ret != -ENODATA) {
+ btrfs_abort_transaction(trans, ret);
+ goto out_end_trans;
+ }
+ }
+
+update_flags:
+ binode->flags = binode_flags;
+ btrfs_sync_inode_flags_to_i_flags(inode);
+ inode_inc_iversion(inode);
+ inode_set_ctime_current(inode);
+ ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
+
+ out_end_trans:
+ btrfs_end_transaction(trans);
+ return ret;
+}
+
+/*
+ * Start exclusive operation @type, return true on success
+ */
+bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
+ enum btrfs_exclusive_operation type)
+{
+ bool ret = false;
+
+ spin_lock(&fs_info->super_lock);
+ if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) {
+ fs_info->exclusive_operation = type;
+ ret = true;
+ }
+ spin_unlock(&fs_info->super_lock);
+
+ return ret;
+}
+
+/*
+ * Conditionally allow to enter the exclusive operation in case it's compatible
+ * with the running one. This must be paired with btrfs_exclop_start_unlock and
+ * btrfs_exclop_finish.
+ *
+ * Compatibility:
+ * - the same type is already running
+ * - when trying to add a device and balance has been paused
+ * - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller
+ * must check the condition first that would allow none -> @type
+ */
+bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
+ enum btrfs_exclusive_operation type)
+{
+ spin_lock(&fs_info->super_lock);
+ if (fs_info->exclusive_operation == type ||
+ (fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED &&
+ type == BTRFS_EXCLOP_DEV_ADD))
+ return true;
+
+ spin_unlock(&fs_info->super_lock);
+ return false;
+}
+
+void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info)
+{
+ spin_unlock(&fs_info->super_lock);
+}
+
+void btrfs_exclop_finish(struct btrfs_fs_info *fs_info)
+{
+ spin_lock(&fs_info->super_lock);
+ WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE);
+ spin_unlock(&fs_info->super_lock);
+ sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation");
+}
+
+void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,
+ enum btrfs_exclusive_operation op)
+{
+ switch (op) {
+ case BTRFS_EXCLOP_BALANCE_PAUSED:
+ spin_lock(&fs_info->super_lock);
+ ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE ||
+ fs_info->exclusive_operation == BTRFS_EXCLOP_DEV_ADD ||
+ fs_info->exclusive_operation == BTRFS_EXCLOP_NONE ||
+ fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
+ fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE_PAUSED;
+ spin_unlock(&fs_info->super_lock);
+ break;
+ case BTRFS_EXCLOP_BALANCE:
+ 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);
+ break;
+ default:
+ btrfs_warn(fs_info,
+ "invalid exclop balance operation %d requested", op);
+ }
+}
+
+static int btrfs_ioctl_getversion(struct inode *inode, int __user *arg)
+{
+ return put_user(inode->i_generation, arg);
+}
+
+static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_device *device;
+ struct fstrim_range range;
+ u64 minlen = ULLONG_MAX;
+ u64 num_devices = 0;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ /*
+ * btrfs_trim_block_group() depends on space cache, which is not
+ * available in zoned filesystem. So, disallow fitrim on a zoned
+ * filesystem for now.
+ */
+ if (btrfs_is_zoned(fs_info))
+ return -EOPNOTSUPP;
+
+ /*
+ * If the fs is mounted with nologreplay, which requires it to be
+ * mounted in RO mode as well, we can not allow discard on free space
+ * inside block groups, because log trees refer to extents that are not
+ * pinned in a block group's free space cache (pinning the extents is
+ * precisely the first phase of replaying a log tree).
+ */
+ if (btrfs_test_opt(fs_info, NOLOGREPLAY))
+ return -EROFS;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
+ dev_list) {
+ if (!device->bdev || !bdev_max_discard_sectors(device->bdev))
+ continue;
+ num_devices++;
+ minlen = min_t(u64, bdev_discard_granularity(device->bdev),
+ minlen);
+ }
+ rcu_read_unlock();
+
+ if (!num_devices)
+ return -EOPNOTSUPP;
+ if (copy_from_user(&range, arg, sizeof(range)))
+ return -EFAULT;
+
+ /*
+ * NOTE: Don't truncate the range using super->total_bytes. Bytenr of
+ * block group is in the logical address space, which can be any
+ * sectorsize aligned bytenr in the range [0, U64_MAX].
+ */
+ if (range.len < fs_info->sb->s_blocksize)
+ return -EINVAL;
+
+ range.minlen = max(range.minlen, minlen);
+ ret = btrfs_trim_fs(fs_info, &range);
+ if (ret < 0)
+ return ret;
+
+ if (copy_to_user(arg, &range, sizeof(range)))
+ return -EFAULT;
+
+ return 0;
+}
+
+int __pure btrfs_is_empty_uuid(u8 *uuid)
+{
+ int i;
+
+ for (i = 0; i < BTRFS_UUID_SIZE; i++) {
+ if (uuid[i])
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * Calculate the number of transaction items to reserve for creating a subvolume
+ * or snapshot, not including the inode, directory entries, or parent directory.
+ */
+static unsigned int create_subvol_num_items(struct btrfs_qgroup_inherit *inherit)
+{
+ /*
+ * 1 to add root block
+ * 1 to add root item
+ * 1 to add root ref
+ * 1 to add root backref
+ * 1 to add UUID item
+ * 1 to add qgroup info
+ * 1 to add qgroup limit
+ *
+ * Ideally the last two would only be accounted if qgroups are enabled,
+ * but that can change between now and the time we would insert them.
+ */
+ unsigned int num_items = 7;
+
+ if (inherit) {
+ /* 2 to add qgroup relations for each inherited qgroup */
+ num_items += 2 * inherit->num_qgroups;
+ }
+ return num_items;
+}
+
+static noinline int create_subvol(struct mnt_idmap *idmap,
+ struct inode *dir, struct dentry *dentry,
+ struct btrfs_qgroup_inherit *inherit)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
+ struct btrfs_trans_handle *trans;
+ struct btrfs_key key;
+ struct btrfs_root_item *root_item;
+ struct btrfs_inode_item *inode_item;
+ struct extent_buffer *leaf;
+ struct btrfs_root *root = BTRFS_I(dir)->root;
+ struct btrfs_root *new_root;
+ struct btrfs_block_rsv block_rsv;
+ struct timespec64 cur_time = current_time(dir);
+ struct btrfs_new_inode_args new_inode_args = {
+ .dir = dir,
+ .dentry = dentry,
+ .subvol = true,
+ };
+ unsigned int trans_num_items;
+ int ret;
+ dev_t anon_dev;
+ u64 objectid;
+
+ root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
+ if (!root_item)
+ return -ENOMEM;
+
+ ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid);
+ if (ret)
+ goto out_root_item;
+
+ /*
+ * Don't create subvolume whose level is not zero. Or qgroup will be
+ * screwed up since it assumes subvolume qgroup's level to be 0.
+ */
+ if (btrfs_qgroup_level(objectid)) {
+ ret = -ENOSPC;
+ goto out_root_item;
+ }
+
+ ret = get_anon_bdev(&anon_dev);
+ if (ret < 0)
+ goto out_root_item;
+
+ new_inode_args.inode = btrfs_new_subvol_inode(idmap, dir);
+ if (!new_inode_args.inode) {
+ ret = -ENOMEM;
+ goto out_anon_dev;
+ }
+ ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items);
+ if (ret)
+ goto out_inode;
+ trans_num_items += create_subvol_num_items(inherit);
+
+ btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
+ ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
+ trans_num_items, false);
+ if (ret)
+ goto out_new_inode_args;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ btrfs_subvolume_release_metadata(root, &block_rsv);
+ goto out_new_inode_args;
+ }
+ trans->block_rsv = &block_rsv;
+ trans->bytes_reserved = block_rsv.size;
+ /* Tree log can't currently deal with an inode which is a new root. */
+ btrfs_set_log_full_commit(trans);
+
+ ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
+ if (ret)
+ goto out;
+
+ leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
+ BTRFS_NESTING_NORMAL);
+ if (IS_ERR(leaf)) {
+ ret = PTR_ERR(leaf);
+ goto out;
+ }
+
+ btrfs_mark_buffer_dirty(trans, leaf);
+
+ inode_item = &root_item->inode;
+ btrfs_set_stack_inode_generation(inode_item, 1);
+ btrfs_set_stack_inode_size(inode_item, 3);
+ btrfs_set_stack_inode_nlink(inode_item, 1);
+ btrfs_set_stack_inode_nbytes(inode_item,
+ fs_info->nodesize);
+ btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
+
+ btrfs_set_root_flags(root_item, 0);
+ btrfs_set_root_limit(root_item, 0);
+ btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
+
+ btrfs_set_root_bytenr(root_item, leaf->start);
+ btrfs_set_root_generation(root_item, trans->transid);
+ btrfs_set_root_level(root_item, 0);
+ btrfs_set_root_refs(root_item, 1);
+ btrfs_set_root_used(root_item, leaf->len);
+ btrfs_set_root_last_snapshot(root_item, 0);
+
+ btrfs_set_root_generation_v2(root_item,
+ btrfs_root_generation(root_item));
+ generate_random_guid(root_item->uuid);
+ btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
+ btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
+ root_item->ctime = root_item->otime;
+ btrfs_set_root_ctransid(root_item, trans->transid);
+ btrfs_set_root_otransid(root_item, trans->transid);
+
+ btrfs_tree_unlock(leaf);
+
+ btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID);
+
+ key.objectid = objectid;
+ key.offset = 0;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+ ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
+ root_item);
+ if (ret) {
+ /*
+ * Since we don't abort the transaction in this case, free the
+ * tree block so that we don't leak space and leave the
+ * filesystem in an inconsistent state (an extent item in the
+ * extent tree with a backreference for a root that does not
+ * exists).
+ */
+ btrfs_tree_lock(leaf);
+ btrfs_clear_buffer_dirty(trans, leaf);
+ btrfs_tree_unlock(leaf);
+ btrfs_free_tree_block(trans, objectid, leaf, 0, 1);
+ free_extent_buffer(leaf);
+ goto out;
+ }
+
+ free_extent_buffer(leaf);
+ leaf = NULL;
+
+ new_root = btrfs_get_new_fs_root(fs_info, objectid, anon_dev);
+ if (IS_ERR(new_root)) {
+ ret = PTR_ERR(new_root);
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+ /* anon_dev is owned by new_root now. */
+ anon_dev = 0;
+ BTRFS_I(new_inode_args.inode)->root = new_root;
+ /* ... and new_root is owned by new_inode_args.inode now. */
+
+ ret = btrfs_record_root_in_trans(trans, new_root);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ ret = btrfs_uuid_tree_add(trans, root_item->uuid,
+ BTRFS_UUID_KEY_SUBVOL, objectid);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ ret = btrfs_create_new_inode(trans, &new_inode_args);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ goto out;
+ }
+
+ d_instantiate_new(dentry, new_inode_args.inode);
+ new_inode_args.inode = NULL;
+
+out:
+ trans->block_rsv = NULL;
+ trans->bytes_reserved = 0;
+ btrfs_subvolume_release_metadata(root, &block_rsv);
+
+ btrfs_end_transaction(trans);
+out_new_inode_args:
+ btrfs_new_inode_args_destroy(&new_inode_args);
+out_inode:
+ iput(new_inode_args.inode);
+out_anon_dev:
+ if (anon_dev)
+ free_anon_bdev(anon_dev);
+out_root_item:
+ kfree(root_item);
+ return ret;
+}
+
+static int create_snapshot(struct btrfs_root *root, struct inode *dir,
+ struct dentry *dentry, bool readonly,
+ struct btrfs_qgroup_inherit *inherit)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
+ struct inode *inode;
+ struct btrfs_pending_snapshot *pending_snapshot;
+ unsigned int trans_num_items;
+ struct btrfs_trans_handle *trans;
+ int ret;
+
+ /* We do not support snapshotting right now. */
+ if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
+ btrfs_warn(fs_info,
+ "extent tree v2 doesn't support snapshotting yet");
+ return -EOPNOTSUPP;
+ }
+
+ if (btrfs_root_refs(&root->root_item) == 0)
+ return -ENOENT;
+
+ if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
+ return -EINVAL;
+
+ if (atomic_read(&root->nr_swapfiles)) {
+ btrfs_warn(fs_info,
+ "cannot snapshot subvolume with active swapfile");
+ return -ETXTBSY;
+ }
+
+ pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
+ if (!pending_snapshot)
+ return -ENOMEM;
+
+ ret = get_anon_bdev(&pending_snapshot->anon_dev);
+ if (ret < 0)
+ goto free_pending;
+ pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
+ GFP_KERNEL);
+ pending_snapshot->path = btrfs_alloc_path();
+ if (!pending_snapshot->root_item || !pending_snapshot->path) {
+ ret = -ENOMEM;
+ goto free_pending;
+ }
+
+ btrfs_init_block_rsv(&pending_snapshot->block_rsv,
+ BTRFS_BLOCK_RSV_TEMP);
+ /*
+ * 1 to add dir item
+ * 1 to add dir index
+ * 1 to update parent inode item
+ */
+ trans_num_items = create_subvol_num_items(inherit) + 3;
+ ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
+ &pending_snapshot->block_rsv,
+ trans_num_items, false);
+ if (ret)
+ goto free_pending;
+
+ pending_snapshot->dentry = dentry;
+ pending_snapshot->root = root;
+ pending_snapshot->readonly = readonly;
+ pending_snapshot->dir = dir;
+ pending_snapshot->inherit = inherit;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto fail;
+ }
+
+ trans->pending_snapshot = pending_snapshot;
+
+ ret = btrfs_commit_transaction(trans);
+ if (ret)
+ goto fail;
+
+ ret = pending_snapshot->error;
+ if (ret)
+ goto fail;
+
+ ret = btrfs_orphan_cleanup(pending_snapshot->snap);
+ if (ret)
+ goto fail;
+
+ inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
+ if (IS_ERR(inode)) {
+ ret = PTR_ERR(inode);
+ goto fail;
+ }
+
+ d_instantiate(dentry, inode);
+ ret = 0;
+ pending_snapshot->anon_dev = 0;
+fail:
+ /* Prevent double freeing of anon_dev */
+ if (ret && pending_snapshot->snap)
+ pending_snapshot->snap->anon_dev = 0;
+ btrfs_put_root(pending_snapshot->snap);
+ btrfs_subvolume_release_metadata(root, &pending_snapshot->block_rsv);
+free_pending:
+ if (pending_snapshot->anon_dev)
+ free_anon_bdev(pending_snapshot->anon_dev);
+ kfree(pending_snapshot->root_item);
+ btrfs_free_path(pending_snapshot->path);
+ kfree(pending_snapshot);
+
+ return ret;
+}
+
+/* copy of may_delete in fs/namei.c()
+ * Check whether we can remove a link victim from directory dir, check
+ * whether the type of victim is right.
+ * 1. We can't do it if dir is read-only (done in permission())
+ * 2. We should have write and exec permissions on dir
+ * 3. We can't remove anything from append-only dir
+ * 4. We can't do anything with immutable dir (done in permission())
+ * 5. If the sticky bit on dir is set we should either
+ * a. be owner of dir, or
+ * b. be owner of victim, or
+ * c. have CAP_FOWNER capability
+ * 6. If the victim is append-only or immutable we can't do anything with
+ * links pointing to it.
+ * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
+ * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
+ * 9. We can't remove a root or mountpoint.
+ * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
+ * nfs_async_unlink().
+ */
+
+static int btrfs_may_delete(struct mnt_idmap *idmap,
+ struct inode *dir, struct dentry *victim, int isdir)
+{
+ int error;
+
+ if (d_really_is_negative(victim))
+ return -ENOENT;
+
+ BUG_ON(d_inode(victim->d_parent) != dir);
+ audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
+
+ error = inode_permission(idmap, dir, MAY_WRITE | MAY_EXEC);
+ if (error)
+ return error;
+ if (IS_APPEND(dir))
+ return -EPERM;
+ if (check_sticky(idmap, dir, d_inode(victim)) ||
+ IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||
+ IS_SWAPFILE(d_inode(victim)))
+ return -EPERM;
+ if (isdir) {
+ if (!d_is_dir(victim))
+ return -ENOTDIR;
+ if (IS_ROOT(victim))
+ return -EBUSY;
+ } else if (d_is_dir(victim))
+ return -EISDIR;
+ if (IS_DEADDIR(dir))
+ return -ENOENT;
+ if (victim->d_flags & DCACHE_NFSFS_RENAMED)
+ return -EBUSY;
+ return 0;
+}
+
+/* copy of may_create in fs/namei.c() */
+static inline int btrfs_may_create(struct mnt_idmap *idmap,
+ struct inode *dir, struct dentry *child)
+{
+ if (d_really_is_positive(child))
+ return -EEXIST;
+ if (IS_DEADDIR(dir))
+ return -ENOENT;
+ if (!fsuidgid_has_mapping(dir->i_sb, idmap))
+ return -EOVERFLOW;
+ return inode_permission(idmap, dir, MAY_WRITE | MAY_EXEC);
+}
+
+/*
+ * Create a new subvolume below @parent. This is largely modeled after
+ * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
+ * inside this filesystem so it's quite a bit simpler.
+ */
+static noinline int btrfs_mksubvol(const struct path *parent,
+ struct mnt_idmap *idmap,
+ const char *name, int namelen,
+ struct btrfs_root *snap_src,
+ bool readonly,
+ struct btrfs_qgroup_inherit *inherit)
+{
+ struct inode *dir = d_inode(parent->dentry);
+ struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
+ struct dentry *dentry;
+ struct fscrypt_str name_str = FSTR_INIT((char *)name, namelen);
+ int error;
+
+ error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
+ if (error == -EINTR)
+ return error;
+
+ dentry = lookup_one(idmap, name, parent->dentry, namelen);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out_unlock;
+
+ error = btrfs_may_create(idmap, dir, dentry);
+ if (error)
+ goto out_dput;
+
+ /*
+ * even if this name doesn't exist, we may get hash collisions.
+ * check for them now when we can safely fail
+ */
+ error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
+ dir->i_ino, &name_str);
+ if (error)
+ goto out_dput;
+
+ down_read(&fs_info->subvol_sem);
+
+ if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
+ goto out_up_read;
+
+ if (snap_src)
+ error = create_snapshot(snap_src, dir, dentry, readonly, inherit);
+ else
+ error = create_subvol(idmap, dir, dentry, inherit);
+
+ if (!error)
+ fsnotify_mkdir(dir, dentry);
+out_up_read:
+ up_read(&fs_info->subvol_sem);
+out_dput:
+ dput(dentry);
+out_unlock:
+ btrfs_inode_unlock(BTRFS_I(dir), 0);
+ return error;
+}
+
+static noinline int btrfs_mksnapshot(const struct path *parent,
+ struct mnt_idmap *idmap,
+ const char *name, int namelen,
+ struct btrfs_root *root,
+ bool readonly,
+ struct btrfs_qgroup_inherit *inherit)
+{
+ int ret;
+ bool snapshot_force_cow = false;
+
+ /*
+ * Force new buffered writes to reserve space even when NOCOW is
+ * possible. This is to avoid later writeback (running dealloc) to
+ * fallback to COW mode and unexpectedly fail with ENOSPC.
+ */
+ btrfs_drew_read_lock(&root->snapshot_lock);
+
+ ret = btrfs_start_delalloc_snapshot(root, false);
+ if (ret)
+ goto out;
+
+ /*
+ * All previous writes have started writeback in NOCOW mode, so now
+ * we force future writes to fallback to COW mode during snapshot
+ * creation.
+ */
+ atomic_inc(&root->snapshot_force_cow);
+ snapshot_force_cow = true;
+
+ btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
+
+ ret = btrfs_mksubvol(parent, idmap, name, namelen,
+ root, readonly, inherit);
+out:
+ if (snapshot_force_cow)
+ atomic_dec(&root->snapshot_force_cow);
+ btrfs_drew_read_unlock(&root->snapshot_lock);
+ return ret;
+}
+
+/*
+ * Try to start exclusive operation @type or cancel it if it's running.
+ *
+ * Return:
+ * 0 - normal mode, newly claimed op started
+ * >0 - normal mode, something else is running,
+ * return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space
+ * ECANCELED - cancel mode, successful cancel
+ * ENOTCONN - cancel mode, operation not running anymore
+ */
+static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info,
+ enum btrfs_exclusive_operation type, bool cancel)
+{
+ if (!cancel) {
+ /* Start normal op */
+ if (!btrfs_exclop_start(fs_info, type))
+ return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
+ /* Exclusive operation is now claimed */
+ return 0;
+ }
+
+ /* Cancel running op */
+ if (btrfs_exclop_start_try_lock(fs_info, type)) {
+ /*
+ * This blocks any exclop finish from setting it to NONE, so we
+ * request cancellation. Either it runs and we will wait for it,
+ * or it has finished and no waiting will happen.
+ */
+ atomic_inc(&fs_info->reloc_cancel_req);
+ btrfs_exclop_start_unlock(fs_info);
+
+ if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags))
+ wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING,
+ TASK_INTERRUPTIBLE);
+
+ return -ECANCELED;
+ }
+
+ /* Something else is running or none */
+ return -ENOTCONN;
+}
+
+static noinline int btrfs_ioctl_resize(struct file *file,
+ void __user *arg)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ u64 new_size;
+ u64 old_size;
+ u64 devid = 1;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_ioctl_vol_args *vol_args;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_device *device = NULL;
+ char *sizestr;
+ char *retptr;
+ char *devstr = NULL;
+ int ret = 0;
+ int mod = 0;
+ bool cancel;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ /*
+ * Read the arguments before checking exclusivity to be able to
+ * distinguish regular resize and cancel
+ */
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args)) {
+ ret = PTR_ERR(vol_args);
+ goto out_drop;
+ }
+ vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+ sizestr = vol_args->name;
+ cancel = (strcmp("cancel", sizestr) == 0);
+ ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel);
+ if (ret)
+ goto out_free;
+ /* Exclusive operation is now claimed */
+
+ devstr = strchr(sizestr, ':');
+ if (devstr) {
+ sizestr = devstr + 1;
+ *devstr = '\0';
+ devstr = vol_args->name;
+ ret = kstrtoull(devstr, 10, &devid);
+ if (ret)
+ goto out_finish;
+ if (!devid) {
+ ret = -EINVAL;
+ goto out_finish;
+ }
+ btrfs_info(fs_info, "resizing devid %llu", devid);
+ }
+
+ args.devid = devid;
+ device = btrfs_find_device(fs_info->fs_devices, &args);
+ if (!device) {
+ btrfs_info(fs_info, "resizer unable to find device %llu",
+ devid);
+ ret = -ENODEV;
+ goto out_finish;
+ }
+
+ if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
+ btrfs_info(fs_info,
+ "resizer unable to apply on readonly device %llu",
+ devid);
+ ret = -EPERM;
+ goto out_finish;
+ }
+
+ if (!strcmp(sizestr, "max"))
+ new_size = bdev_nr_bytes(device->bdev);
+ else {
+ if (sizestr[0] == '-') {
+ mod = -1;
+ sizestr++;
+ } else if (sizestr[0] == '+') {
+ mod = 1;
+ sizestr++;
+ }
+ new_size = memparse(sizestr, &retptr);
+ if (*retptr != '\0' || new_size == 0) {
+ ret = -EINVAL;
+ goto out_finish;
+ }
+ }
+
+ if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
+ ret = -EPERM;
+ goto out_finish;
+ }
+
+ old_size = btrfs_device_get_total_bytes(device);
+
+ if (mod < 0) {
+ if (new_size > old_size) {
+ ret = -EINVAL;
+ goto out_finish;
+ }
+ new_size = old_size - new_size;
+ } else if (mod > 0) {
+ if (new_size > ULLONG_MAX - old_size) {
+ ret = -ERANGE;
+ goto out_finish;
+ }
+ new_size = old_size + new_size;
+ }
+
+ if (new_size < SZ_256M) {
+ ret = -EINVAL;
+ goto out_finish;
+ }
+ if (new_size > bdev_nr_bytes(device->bdev)) {
+ ret = -EFBIG;
+ goto out_finish;
+ }
+
+ new_size = round_down(new_size, fs_info->sectorsize);
+
+ if (new_size > old_size) {
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_finish;
+ }
+ ret = btrfs_grow_device(trans, device, new_size);
+ btrfs_commit_transaction(trans);
+ } else if (new_size < old_size) {
+ ret = btrfs_shrink_device(device, new_size);
+ } /* equal, nothing need to do */
+
+ if (ret == 0 && new_size != old_size)
+ btrfs_info_in_rcu(fs_info,
+ "resize device %s (devid %llu) from %llu to %llu",
+ btrfs_dev_name(device), device->devid,
+ old_size, new_size);
+out_finish:
+ btrfs_exclop_finish(fs_info);
+out_free:
+ kfree(vol_args);
+out_drop:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static noinline int __btrfs_ioctl_snap_create(struct file *file,
+ struct mnt_idmap *idmap,
+ const char *name, unsigned long fd, int subvol,
+ bool readonly,
+ struct btrfs_qgroup_inherit *inherit)
+{
+ int namelen;
+ int ret = 0;
+
+ if (!S_ISDIR(file_inode(file)->i_mode))
+ return -ENOTDIR;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ goto out;
+
+ namelen = strlen(name);
+ if (strchr(name, '/')) {
+ ret = -EINVAL;
+ goto out_drop_write;
+ }
+
+ if (name[0] == '.' &&
+ (namelen == 1 || (name[1] == '.' && namelen == 2))) {
+ ret = -EEXIST;
+ goto out_drop_write;
+ }
+
+ if (subvol) {
+ ret = btrfs_mksubvol(&file->f_path, idmap, name,
+ namelen, NULL, readonly, inherit);
+ } else {
+ struct fd src = fdget(fd);
+ struct inode *src_inode;
+ if (!src.file) {
+ ret = -EINVAL;
+ goto out_drop_write;
+ }
+
+ src_inode = file_inode(src.file);
+ if (src_inode->i_sb != file_inode(file)->i_sb) {
+ btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
+ "Snapshot src from another FS");
+ ret = -EXDEV;
+ } else if (!inode_owner_or_capable(idmap, src_inode)) {
+ /*
+ * Subvolume creation is not restricted, but snapshots
+ * are limited to own subvolumes only
+ */
+ ret = -EPERM;
+ } else if (btrfs_ino(BTRFS_I(src_inode)) != BTRFS_FIRST_FREE_OBJECTID) {
+ /*
+ * Snapshots must be made with the src_inode referring
+ * to the subvolume inode, otherwise the permission
+ * checking above is useless because we may have
+ * permission on a lower directory but not the subvol
+ * itself.
+ */
+ ret = -EINVAL;
+ } else {
+ ret = btrfs_mksnapshot(&file->f_path, idmap,
+ name, namelen,
+ BTRFS_I(src_inode)->root,
+ readonly, inherit);
+ }
+ fdput(src);
+ }
+out_drop_write:
+ mnt_drop_write_file(file);
+out:
+ return ret;
+}
+
+static noinline int btrfs_ioctl_snap_create(struct file *file,
+ void __user *arg, int subvol)
+{
+ struct btrfs_ioctl_vol_args *vol_args;
+ int ret;
+
+ if (!S_ISDIR(file_inode(file)->i_mode))
+ return -ENOTDIR;
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+ vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+
+ ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file),
+ vol_args->name, vol_args->fd, subvol,
+ false, NULL);
+
+ kfree(vol_args);
+ return ret;
+}
+
+static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
+ void __user *arg, int subvol)
+{
+ struct btrfs_ioctl_vol_args_v2 *vol_args;
+ int ret;
+ bool readonly = false;
+ struct btrfs_qgroup_inherit *inherit = NULL;
+
+ if (!S_ISDIR(file_inode(file)->i_mode))
+ return -ENOTDIR;
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+ vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
+
+ if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {
+ ret = -EOPNOTSUPP;
+ goto free_args;
+ }
+
+ if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
+ readonly = true;
+ if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
+ u64 nums;
+
+ if (vol_args->size < sizeof(*inherit) ||
+ vol_args->size > PAGE_SIZE) {
+ ret = -EINVAL;
+ goto free_args;
+ }
+ inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
+ if (IS_ERR(inherit)) {
+ ret = PTR_ERR(inherit);
+ goto free_args;
+ }
+
+ if (inherit->num_qgroups > PAGE_SIZE ||
+ inherit->num_ref_copies > PAGE_SIZE ||
+ inherit->num_excl_copies > PAGE_SIZE) {
+ ret = -EINVAL;
+ goto free_inherit;
+ }
+
+ nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
+ 2 * inherit->num_excl_copies;
+ if (vol_args->size != struct_size(inherit, qgroups, nums)) {
+ ret = -EINVAL;
+ goto free_inherit;
+ }
+ }
+
+ ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file),
+ vol_args->name, vol_args->fd, subvol,
+ readonly, inherit);
+ if (ret)
+ goto free_inherit;
+free_inherit:
+ kfree(inherit);
+free_args:
+ kfree(vol_args);
+ return ret;
+}
+
+static noinline int btrfs_ioctl_subvol_getflags(struct inode *inode,
+ void __user *arg)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ int ret = 0;
+ u64 flags = 0;
+
+ if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
+ return -EINVAL;
+
+ down_read(&fs_info->subvol_sem);
+ if (btrfs_root_readonly(root))
+ flags |= BTRFS_SUBVOL_RDONLY;
+ up_read(&fs_info->subvol_sem);
+
+ if (copy_to_user(arg, &flags, sizeof(flags)))
+ ret = -EFAULT;
+
+ return ret;
+}
+
+static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
+ void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+ u64 root_flags;
+ u64 flags;
+ int ret = 0;
+
+ if (!inode_owner_or_capable(file_mnt_idmap(file), inode))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ goto out;
+
+ if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
+ ret = -EINVAL;
+ goto out_drop_write;
+ }
+
+ if (copy_from_user(&flags, arg, sizeof(flags))) {
+ ret = -EFAULT;
+ goto out_drop_write;
+ }
+
+ if (flags & ~BTRFS_SUBVOL_RDONLY) {
+ ret = -EOPNOTSUPP;
+ goto out_drop_write;
+ }
+
+ down_write(&fs_info->subvol_sem);
+
+ /* nothing to do */
+ if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
+ goto out_drop_sem;
+
+ root_flags = btrfs_root_flags(&root->root_item);
+ if (flags & BTRFS_SUBVOL_RDONLY) {
+ btrfs_set_root_flags(&root->root_item,
+ root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
+ } else {
+ /*
+ * Block RO -> RW transition if this subvolume is involved in
+ * send
+ */
+ spin_lock(&root->root_item_lock);
+ if (root->send_in_progress == 0) {
+ btrfs_set_root_flags(&root->root_item,
+ root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
+ spin_unlock(&root->root_item_lock);
+ } else {
+ spin_unlock(&root->root_item_lock);
+ btrfs_warn(fs_info,
+ "Attempt to set subvolume %llu read-write during send",
+ root->root_key.objectid);
+ ret = -EPERM;
+ goto out_drop_sem;
+ }
+ }
+
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_reset;
+ }
+
+ ret = btrfs_update_root(trans, fs_info->tree_root,
+ &root->root_key, &root->root_item);
+ if (ret < 0) {
+ btrfs_end_transaction(trans);
+ goto out_reset;
+ }
+
+ ret = btrfs_commit_transaction(trans);
+
+out_reset:
+ if (ret)
+ btrfs_set_root_flags(&root->root_item, root_flags);
+out_drop_sem:
+ up_write(&fs_info->subvol_sem);
+out_drop_write:
+ mnt_drop_write_file(file);
+out:
+ return ret;
+}
+
+static noinline int key_in_sk(struct btrfs_key *key,
+ struct btrfs_ioctl_search_key *sk)
+{
+ struct btrfs_key test;
+ int ret;
+
+ test.objectid = sk->min_objectid;
+ test.type = sk->min_type;
+ test.offset = sk->min_offset;
+
+ ret = btrfs_comp_cpu_keys(key, &test);
+ if (ret < 0)
+ return 0;
+
+ test.objectid = sk->max_objectid;
+ test.type = sk->max_type;
+ test.offset = sk->max_offset;
+
+ ret = btrfs_comp_cpu_keys(key, &test);
+ if (ret > 0)
+ return 0;
+ return 1;
+}
+
+static noinline int copy_to_sk(struct btrfs_path *path,
+ struct btrfs_key *key,
+ struct btrfs_ioctl_search_key *sk,
+ u64 *buf_size,
+ char __user *ubuf,
+ unsigned long *sk_offset,
+ int *num_found)
+{
+ u64 found_transid;
+ struct extent_buffer *leaf;
+ struct btrfs_ioctl_search_header sh;
+ struct btrfs_key test;
+ unsigned long item_off;
+ unsigned long item_len;
+ int nritems;
+ int i;
+ int slot;
+ int ret = 0;
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ nritems = btrfs_header_nritems(leaf);
+
+ if (btrfs_header_generation(leaf) > sk->max_transid) {
+ i = nritems;
+ goto advance_key;
+ }
+ found_transid = btrfs_header_generation(leaf);
+
+ for (i = slot; i < nritems; i++) {
+ item_off = btrfs_item_ptr_offset(leaf, i);
+ item_len = btrfs_item_size(leaf, i);
+
+ btrfs_item_key_to_cpu(leaf, key, i);
+ if (!key_in_sk(key, sk))
+ continue;
+
+ if (sizeof(sh) + item_len > *buf_size) {
+ if (*num_found) {
+ ret = 1;
+ goto out;
+ }
+
+ /*
+ * return one empty item back for v1, which does not
+ * handle -EOVERFLOW
+ */
+
+ *buf_size = sizeof(sh) + item_len;
+ item_len = 0;
+ ret = -EOVERFLOW;
+ }
+
+ if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
+ ret = 1;
+ goto out;
+ }
+
+ sh.objectid = key->objectid;
+ sh.offset = key->offset;
+ sh.type = key->type;
+ sh.len = item_len;
+ sh.transid = found_transid;
+
+ /*
+ * Copy search result header. If we fault then loop again so we
+ * can fault in the pages and -EFAULT there if there's a
+ * problem. Otherwise we'll fault and then copy the buffer in
+ * properly this next time through
+ */
+ if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
+ ret = 0;
+ goto out;
+ }
+
+ *sk_offset += sizeof(sh);
+
+ if (item_len) {
+ char __user *up = ubuf + *sk_offset;
+ /*
+ * Copy the item, same behavior as above, but reset the
+ * * sk_offset so we copy the full thing again.
+ */
+ if (read_extent_buffer_to_user_nofault(leaf, up,
+ item_off, item_len)) {
+ ret = 0;
+ *sk_offset -= sizeof(sh);
+ goto out;
+ }
+
+ *sk_offset += item_len;
+ }
+ (*num_found)++;
+
+ if (ret) /* -EOVERFLOW from above */
+ goto out;
+
+ if (*num_found >= sk->nr_items) {
+ ret = 1;
+ goto out;
+ }
+ }
+advance_key:
+ ret = 0;
+ test.objectid = sk->max_objectid;
+ test.type = sk->max_type;
+ test.offset = sk->max_offset;
+ if (btrfs_comp_cpu_keys(key, &test) >= 0)
+ ret = 1;
+ else if (key->offset < (u64)-1)
+ key->offset++;
+ else if (key->type < (u8)-1) {
+ key->offset = 0;
+ key->type++;
+ } else if (key->objectid < (u64)-1) {
+ key->offset = 0;
+ key->type = 0;
+ key->objectid++;
+ } else
+ ret = 1;
+out:
+ /*
+ * 0: all items from this leaf copied, continue with next
+ * 1: * more items can be copied, but unused buffer is too small
+ * * all items were found
+ * Either way, it will stops the loop which iterates to the next
+ * leaf
+ * -EOVERFLOW: item was to large for buffer
+ * -EFAULT: could not copy extent buffer back to userspace
+ */
+ return ret;
+}
+
+static noinline int search_ioctl(struct inode *inode,
+ struct btrfs_ioctl_search_key *sk,
+ u64 *buf_size,
+ char __user *ubuf)
+{
+ struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root;
+ struct btrfs_key key;
+ struct btrfs_path *path;
+ int ret;
+ int num_found = 0;
+ unsigned long sk_offset = 0;
+
+ if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
+ *buf_size = sizeof(struct btrfs_ioctl_search_header);
+ return -EOVERFLOW;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ if (sk->tree_id == 0) {
+ /* search the root of the inode that was passed */
+ root = btrfs_grab_root(BTRFS_I(inode)->root);
+ } else {
+ root = btrfs_get_fs_root(info, sk->tree_id, true);
+ if (IS_ERR(root)) {
+ btrfs_free_path(path);
+ return PTR_ERR(root);
+ }
+ }
+
+ key.objectid = sk->min_objectid;
+ key.type = sk->min_type;
+ key.offset = sk->min_offset;
+
+ while (1) {
+ ret = -EFAULT;
+ /*
+ * Ensure that the whole user buffer is faulted in at sub-page
+ * granularity, otherwise the loop may live-lock.
+ */
+ if (fault_in_subpage_writeable(ubuf + sk_offset,
+ *buf_size - sk_offset))
+ break;
+
+ ret = btrfs_search_forward(root, &key, path, sk->min_transid);
+ if (ret != 0) {
+ if (ret > 0)
+ ret = 0;
+ goto err;
+ }
+ ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
+ &sk_offset, &num_found);
+ btrfs_release_path(path);
+ if (ret)
+ break;
+
+ }
+ if (ret > 0)
+ ret = 0;
+err:
+ sk->nr_items = num_found;
+ btrfs_put_root(root);
+ btrfs_free_path(path);
+ return ret;
+}
+
+static noinline int btrfs_ioctl_tree_search(struct inode *inode,
+ void __user *argp)
+{
+ struct btrfs_ioctl_search_args __user *uargs = argp;
+ struct btrfs_ioctl_search_key sk;
+ int ret;
+ u64 buf_size;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
+ return -EFAULT;
+
+ buf_size = sizeof(uargs->buf);
+
+ ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
+
+ /*
+ * In the origin implementation an overflow is handled by returning a
+ * search header with a len of zero, so reset ret.
+ */
+ if (ret == -EOVERFLOW)
+ ret = 0;
+
+ if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
+ ret = -EFAULT;
+ return ret;
+}
+
+static noinline int btrfs_ioctl_tree_search_v2(struct inode *inode,
+ void __user *argp)
+{
+ struct btrfs_ioctl_search_args_v2 __user *uarg = argp;
+ struct btrfs_ioctl_search_args_v2 args;
+ int ret;
+ u64 buf_size;
+ const u64 buf_limit = SZ_16M;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ /* copy search header and buffer size */
+ if (copy_from_user(&args, uarg, sizeof(args)))
+ return -EFAULT;
+
+ buf_size = args.buf_size;
+
+ /* limit result size to 16MB */
+ if (buf_size > buf_limit)
+ buf_size = buf_limit;
+
+ ret = search_ioctl(inode, &args.key, &buf_size,
+ (char __user *)(&uarg->buf[0]));
+ if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
+ ret = -EFAULT;
+ else if (ret == -EOVERFLOW &&
+ copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
+ ret = -EFAULT;
+
+ return ret;
+}
+
+/*
+ * Search INODE_REFs to identify path name of 'dirid' directory
+ * in a 'tree_id' tree. and sets path name to 'name'.
+ */
+static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
+ u64 tree_id, u64 dirid, char *name)
+{
+ struct btrfs_root *root;
+ struct btrfs_key key;
+ char *ptr;
+ int ret = -1;
+ int slot;
+ int len;
+ int total_len = 0;
+ struct btrfs_inode_ref *iref;
+ struct extent_buffer *l;
+ struct btrfs_path *path;
+
+ if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
+ name[0]='\0';
+ return 0;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
+
+ root = btrfs_get_fs_root(info, tree_id, true);
+ if (IS_ERR(root)) {
+ ret = PTR_ERR(root);
+ root = NULL;
+ goto out;
+ }
+
+ key.objectid = dirid;
+ key.type = BTRFS_INODE_REF_KEY;
+ key.offset = (u64)-1;
+
+ while (1) {
+ ret = btrfs_search_backwards(root, &key, path);
+ if (ret < 0)
+ goto out;
+ else if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ l = path->nodes[0];
+ slot = path->slots[0];
+
+ iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
+ len = btrfs_inode_ref_name_len(l, iref);
+ ptr -= len + 1;
+ total_len += len + 1;
+ if (ptr < name) {
+ ret = -ENAMETOOLONG;
+ goto out;
+ }
+
+ *(ptr + len) = '/';
+ read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
+
+ if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
+ break;
+
+ btrfs_release_path(path);
+ key.objectid = key.offset;
+ key.offset = (u64)-1;
+ dirid = key.objectid;
+ }
+ memmove(name, ptr, total_len);
+ name[total_len] = '\0';
+ ret = 0;
+out:
+ btrfs_put_root(root);
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap,
+ struct inode *inode,
+ struct btrfs_ioctl_ino_lookup_user_args *args)
+{
+ struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
+ struct super_block *sb = inode->i_sb;
+ struct btrfs_key upper_limit = BTRFS_I(inode)->location;
+ u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
+ u64 dirid = args->dirid;
+ unsigned long item_off;
+ unsigned long item_len;
+ struct btrfs_inode_ref *iref;
+ struct btrfs_root_ref *rref;
+ struct btrfs_root *root = NULL;
+ struct btrfs_path *path;
+ struct btrfs_key key, key2;
+ struct extent_buffer *leaf;
+ struct inode *temp_inode;
+ char *ptr;
+ int slot;
+ int len;
+ int total_len = 0;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ /*
+ * If the bottom subvolume does not exist directly under upper_limit,
+ * construct the path in from the bottom up.
+ */
+ if (dirid != upper_limit.objectid) {
+ ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
+
+ root = btrfs_get_fs_root(fs_info, treeid, true);
+ if (IS_ERR(root)) {
+ ret = PTR_ERR(root);
+ goto out;
+ }
+
+ key.objectid = dirid;
+ key.type = BTRFS_INODE_REF_KEY;
+ key.offset = (u64)-1;
+ while (1) {
+ ret = btrfs_search_backwards(root, &key, path);
+ if (ret < 0)
+ goto out_put;
+ else if (ret > 0) {
+ ret = -ENOENT;
+ goto out_put;
+ }
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+
+ iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
+ len = btrfs_inode_ref_name_len(leaf, iref);
+ ptr -= len + 1;
+ total_len += len + 1;
+ if (ptr < args->path) {
+ ret = -ENAMETOOLONG;
+ goto out_put;
+ }
+
+ *(ptr + len) = '/';
+ read_extent_buffer(leaf, ptr,
+ (unsigned long)(iref + 1), len);
+
+ /* Check the read+exec permission of this directory */
+ ret = btrfs_previous_item(root, path, dirid,
+ BTRFS_INODE_ITEM_KEY);
+ if (ret < 0) {
+ goto out_put;
+ } else if (ret > 0) {
+ ret = -ENOENT;
+ goto out_put;
+ }
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ btrfs_item_key_to_cpu(leaf, &key2, slot);
+ if (key2.objectid != dirid) {
+ ret = -ENOENT;
+ goto out_put;
+ }
+
+ /*
+ * We don't need the path anymore, so release it and
+ * avoid deadlocks and lockdep warnings in case
+ * btrfs_iget() needs to lookup the inode from its root
+ * btree and lock the same leaf.
+ */
+ btrfs_release_path(path);
+ temp_inode = btrfs_iget(sb, key2.objectid, root);
+ if (IS_ERR(temp_inode)) {
+ ret = PTR_ERR(temp_inode);
+ goto out_put;
+ }
+ ret = inode_permission(idmap, temp_inode,
+ MAY_READ | MAY_EXEC);
+ iput(temp_inode);
+ if (ret) {
+ ret = -EACCES;
+ goto out_put;
+ }
+
+ if (key.offset == upper_limit.objectid)
+ break;
+ if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
+ ret = -EACCES;
+ goto out_put;
+ }
+
+ key.objectid = key.offset;
+ key.offset = (u64)-1;
+ dirid = key.objectid;
+ }
+
+ memmove(args->path, ptr, total_len);
+ args->path[total_len] = '\0';
+ btrfs_put_root(root);
+ root = NULL;
+ btrfs_release_path(path);
+ }
+
+ /* Get the bottom subvolume's name from ROOT_REF */
+ key.objectid = treeid;
+ key.type = BTRFS_ROOT_REF_KEY;
+ key.offset = args->treeid;
+ ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
+ if (ret < 0) {
+ goto out;
+ } else if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+
+ item_off = btrfs_item_ptr_offset(leaf, slot);
+ item_len = btrfs_item_size(leaf, slot);
+ /* Check if dirid in ROOT_REF corresponds to passed dirid */
+ rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
+ if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Copy subvolume's name */
+ item_off += sizeof(struct btrfs_root_ref);
+ item_len -= sizeof(struct btrfs_root_ref);
+ read_extent_buffer(leaf, args->name, item_off, item_len);
+ args->name[item_len] = 0;
+
+out_put:
+ btrfs_put_root(root);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static noinline int btrfs_ioctl_ino_lookup(struct btrfs_root *root,
+ void __user *argp)
+{
+ struct btrfs_ioctl_ino_lookup_args *args;
+ int ret = 0;
+
+ args = memdup_user(argp, sizeof(*args));
+ if (IS_ERR(args))
+ return PTR_ERR(args);
+
+ /*
+ * Unprivileged query to obtain the containing subvolume root id. The
+ * path is reset so it's consistent with btrfs_search_path_in_tree.
+ */
+ if (args->treeid == 0)
+ args->treeid = root->root_key.objectid;
+
+ if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
+ args->name[0] = 0;
+ goto out;
+ }
+
+ if (!capable(CAP_SYS_ADMIN)) {
+ ret = -EPERM;
+ goto out;
+ }
+
+ ret = btrfs_search_path_in_tree(root->fs_info,
+ args->treeid, args->objectid,
+ args->name);
+
+out:
+ if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
+ ret = -EFAULT;
+
+ kfree(args);
+ return ret;
+}
+
+/*
+ * Version of ino_lookup ioctl (unprivileged)
+ *
+ * The main differences from ino_lookup ioctl are:
+ *
+ * 1. Read + Exec permission will be checked using inode_permission() during
+ * path construction. -EACCES will be returned in case of failure.
+ * 2. Path construction will be stopped at the inode number which corresponds
+ * to the fd with which this ioctl is called. If constructed path does not
+ * exist under fd's inode, -EACCES will be returned.
+ * 3. The name of bottom subvolume is also searched and filled.
+ */
+static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
+{
+ struct btrfs_ioctl_ino_lookup_user_args *args;
+ struct inode *inode;
+ int ret;
+
+ args = memdup_user(argp, sizeof(*args));
+ if (IS_ERR(args))
+ return PTR_ERR(args);
+
+ inode = file_inode(file);
+
+ if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
+ BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
+ /*
+ * The subvolume does not exist under fd with which this is
+ * called
+ */
+ kfree(args);
+ return -EACCES;
+ }
+
+ ret = btrfs_search_path_in_tree_user(file_mnt_idmap(file), inode, args);
+
+ if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
+ ret = -EFAULT;
+
+ kfree(args);
+ return ret;
+}
+
+/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
+static int btrfs_ioctl_get_subvol_info(struct inode *inode, void __user *argp)
+{
+ struct btrfs_ioctl_get_subvol_info_args *subvol_info;
+ struct btrfs_fs_info *fs_info;
+ struct btrfs_root *root;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct btrfs_root_item *root_item;
+ struct btrfs_root_ref *rref;
+ struct extent_buffer *leaf;
+ unsigned long item_off;
+ unsigned long item_len;
+ int slot;
+ int ret = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
+ if (!subvol_info) {
+ btrfs_free_path(path);
+ return -ENOMEM;
+ }
+
+ fs_info = BTRFS_I(inode)->root->fs_info;
+
+ /* Get root_item of inode's subvolume */
+ key.objectid = BTRFS_I(inode)->root->root_key.objectid;
+ root = btrfs_get_fs_root(fs_info, key.objectid, true);
+ if (IS_ERR(root)) {
+ ret = PTR_ERR(root);
+ goto out_free;
+ }
+ root_item = &root->root_item;
+
+ subvol_info->treeid = key.objectid;
+
+ subvol_info->generation = btrfs_root_generation(root_item);
+ subvol_info->flags = btrfs_root_flags(root_item);
+
+ memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
+ memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
+ BTRFS_UUID_SIZE);
+ memcpy(subvol_info->received_uuid, root_item->received_uuid,
+ BTRFS_UUID_SIZE);
+
+ subvol_info->ctransid = btrfs_root_ctransid(root_item);
+ subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
+ subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
+
+ subvol_info->otransid = btrfs_root_otransid(root_item);
+ subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
+ subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
+
+ subvol_info->stransid = btrfs_root_stransid(root_item);
+ subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
+ subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
+
+ subvol_info->rtransid = btrfs_root_rtransid(root_item);
+ subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
+ subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
+
+ if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
+ /* Search root tree for ROOT_BACKREF of this subvolume */
+ key.type = BTRFS_ROOT_BACKREF_KEY;
+ key.offset = 0;
+ ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
+ if (ret < 0) {
+ goto out;
+ } else if (path->slots[0] >=
+ btrfs_header_nritems(path->nodes[0])) {
+ ret = btrfs_next_leaf(fs_info->tree_root, path);
+ if (ret < 0) {
+ goto out;
+ } else if (ret > 0) {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ }
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+ if (key.objectid == subvol_info->treeid &&
+ key.type == BTRFS_ROOT_BACKREF_KEY) {
+ subvol_info->parent_id = key.offset;
+
+ rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
+ subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
+
+ item_off = btrfs_item_ptr_offset(leaf, slot)
+ + sizeof(struct btrfs_root_ref);
+ item_len = btrfs_item_size(leaf, slot)
+ - sizeof(struct btrfs_root_ref);
+ read_extent_buffer(leaf, subvol_info->name,
+ item_off, item_len);
+ } else {
+ ret = -ENOENT;
+ goto out;
+ }
+ }
+
+ btrfs_free_path(path);
+ path = NULL;
+ if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
+ ret = -EFAULT;
+
+out:
+ btrfs_put_root(root);
+out_free:
+ btrfs_free_path(path);
+ kfree(subvol_info);
+ return ret;
+}
+
+/*
+ * Return ROOT_REF information of the subvolume containing this inode
+ * except the subvolume name.
+ */
+static int btrfs_ioctl_get_subvol_rootref(struct btrfs_root *root,
+ void __user *argp)
+{
+ struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
+ struct btrfs_root_ref *rref;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct extent_buffer *leaf;
+ u64 objectid;
+ int slot;
+ int ret;
+ u8 found;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ rootrefs = memdup_user(argp, sizeof(*rootrefs));
+ if (IS_ERR(rootrefs)) {
+ btrfs_free_path(path);
+ return PTR_ERR(rootrefs);
+ }
+
+ objectid = root->root_key.objectid;
+ key.objectid = objectid;
+ key.type = BTRFS_ROOT_REF_KEY;
+ key.offset = rootrefs->min_treeid;
+ found = 0;
+
+ root = root->fs_info->tree_root;
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0) {
+ goto out;
+ } else if (path->slots[0] >=
+ btrfs_header_nritems(path->nodes[0])) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret < 0) {
+ goto out;
+ } else if (ret > 0) {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ }
+ while (1) {
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+ if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
+ ret = 0;
+ goto out;
+ }
+
+ if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
+ ret = -EOVERFLOW;
+ goto out;
+ }
+
+ rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
+ rootrefs->rootref[found].treeid = key.offset;
+ rootrefs->rootref[found].dirid =
+ btrfs_root_ref_dirid(leaf, rref);
+ found++;
+
+ ret = btrfs_next_item(root, path);
+ if (ret < 0) {
+ goto out;
+ } else if (ret > 0) {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ }
+
+out:
+ btrfs_free_path(path);
+
+ if (!ret || ret == -EOVERFLOW) {
+ rootrefs->num_items = found;
+ /* update min_treeid for next search */
+ if (found)
+ rootrefs->min_treeid =
+ rootrefs->rootref[found - 1].treeid + 1;
+ if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
+ ret = -EFAULT;
+ }
+
+ kfree(rootrefs);
+
+ return ret;
+}
+
+static noinline int btrfs_ioctl_snap_destroy(struct file *file,
+ void __user *arg,
+ bool destroy_v2)
+{
+ struct dentry *parent = file->f_path.dentry;
+ struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
+ struct dentry *dentry;
+ struct inode *dir = d_inode(parent);
+ struct inode *inode;
+ struct btrfs_root *root = BTRFS_I(dir)->root;
+ struct btrfs_root *dest = NULL;
+ struct btrfs_ioctl_vol_args *vol_args = NULL;
+ struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
+ struct mnt_idmap *idmap = file_mnt_idmap(file);
+ char *subvol_name, *subvol_name_ptr = NULL;
+ int subvol_namelen;
+ int err = 0;
+ bool destroy_parent = false;
+
+ /* We don't support snapshots with extent tree v2 yet. */
+ if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
+ btrfs_err(fs_info,
+ "extent tree v2 doesn't support snapshot deletion yet");
+ return -EOPNOTSUPP;
+ }
+
+ if (destroy_v2) {
+ vol_args2 = memdup_user(arg, sizeof(*vol_args2));
+ if (IS_ERR(vol_args2))
+ return PTR_ERR(vol_args2);
+
+ if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
+ err = -EOPNOTSUPP;
+ goto out;
+ }
+
+ /*
+ * If SPEC_BY_ID is not set, we are looking for the subvolume by
+ * name, same as v1 currently does.
+ */
+ if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
+ vol_args2->name[BTRFS_SUBVOL_NAME_MAX] = 0;
+ subvol_name = vol_args2->name;
+
+ err = mnt_want_write_file(file);
+ if (err)
+ goto out;
+ } else {
+ struct inode *old_dir;
+
+ if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ err = mnt_want_write_file(file);
+ if (err)
+ goto out;
+
+ dentry = btrfs_get_dentry(fs_info->sb,
+ BTRFS_FIRST_FREE_OBJECTID,
+ vol_args2->subvolid, 0);
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
+ goto out_drop_write;
+ }
+
+ /*
+ * Change the default parent since the subvolume being
+ * deleted can be outside of the current mount point.
+ */
+ parent = btrfs_get_parent(dentry);
+
+ /*
+ * At this point dentry->d_name can point to '/' if the
+ * subvolume we want to destroy is outsite of the
+ * current mount point, so we need to release the
+ * current dentry and execute the lookup to return a new
+ * one with ->d_name pointing to the
+ * <mount point>/subvol_name.
+ */
+ dput(dentry);
+ if (IS_ERR(parent)) {
+ err = PTR_ERR(parent);
+ goto out_drop_write;
+ }
+ old_dir = dir;
+ dir = d_inode(parent);
+
+ /*
+ * If v2 was used with SPEC_BY_ID, a new parent was
+ * allocated since the subvolume can be outside of the
+ * current mount point. Later on we need to release this
+ * new parent dentry.
+ */
+ destroy_parent = true;
+
+ /*
+ * On idmapped mounts, deletion via subvolid is
+ * restricted to subvolumes that are immediate
+ * ancestors of the inode referenced by the file
+ * descriptor in the ioctl. Otherwise the idmapping
+ * could potentially be abused to delete subvolumes
+ * anywhere in the filesystem the user wouldn't be able
+ * to delete without an idmapped mount.
+ */
+ if (old_dir != dir && idmap != &nop_mnt_idmap) {
+ err = -EOPNOTSUPP;
+ goto free_parent;
+ }
+
+ subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
+ fs_info, vol_args2->subvolid);
+ if (IS_ERR(subvol_name_ptr)) {
+ err = PTR_ERR(subvol_name_ptr);
+ goto free_parent;
+ }
+ /* subvol_name_ptr is already nul terminated */
+ subvol_name = (char *)kbasename(subvol_name_ptr);
+ }
+ } else {
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+
+ vol_args->name[BTRFS_PATH_NAME_MAX] = 0;
+ subvol_name = vol_args->name;
+
+ err = mnt_want_write_file(file);
+ if (err)
+ goto out;
+ }
+
+ subvol_namelen = strlen(subvol_name);
+
+ if (strchr(subvol_name, '/') ||
+ strncmp(subvol_name, "..", subvol_namelen) == 0) {
+ err = -EINVAL;
+ goto free_subvol_name;
+ }
+
+ if (!S_ISDIR(dir->i_mode)) {
+ err = -ENOTDIR;
+ goto free_subvol_name;
+ }
+
+ err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
+ if (err == -EINTR)
+ goto free_subvol_name;
+ dentry = lookup_one(idmap, subvol_name, parent, subvol_namelen);
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
+ goto out_unlock_dir;
+ }
+
+ if (d_really_is_negative(dentry)) {
+ err = -ENOENT;
+ goto out_dput;
+ }
+
+ inode = d_inode(dentry);
+ dest = BTRFS_I(inode)->root;
+ if (!capable(CAP_SYS_ADMIN)) {
+ /*
+ * Regular user. Only allow this with a special mount
+ * option, when the user has write+exec access to the
+ * subvol root, and when rmdir(2) would have been
+ * allowed.
+ *
+ * Note that this is _not_ check that the subvol is
+ * empty or doesn't contain data that we wouldn't
+ * otherwise be able to delete.
+ *
+ * Users who want to delete empty subvols should try
+ * rmdir(2).
+ */
+ err = -EPERM;
+ if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
+ goto out_dput;
+
+ /*
+ * Do not allow deletion if the parent dir is the same
+ * as the dir to be deleted. That means the ioctl
+ * must be called on the dentry referencing the root
+ * of the subvol, not a random directory contained
+ * within it.
+ */
+ err = -EINVAL;
+ if (root == dest)
+ goto out_dput;
+
+ err = inode_permission(idmap, inode, MAY_WRITE | MAY_EXEC);
+ if (err)
+ goto out_dput;
+ }
+
+ /* check if subvolume may be deleted by a user */
+ err = btrfs_may_delete(idmap, dir, dentry, 1);
+ if (err)
+ goto out_dput;
+
+ if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
+ err = -EINVAL;
+ goto out_dput;
+ }
+
+ btrfs_inode_lock(BTRFS_I(inode), 0);
+ err = btrfs_delete_subvolume(BTRFS_I(dir), dentry);
+ btrfs_inode_unlock(BTRFS_I(inode), 0);
+ if (!err)
+ d_delete_notify(dir, dentry);
+
+out_dput:
+ dput(dentry);
+out_unlock_dir:
+ btrfs_inode_unlock(BTRFS_I(dir), 0);
+free_subvol_name:
+ kfree(subvol_name_ptr);
+free_parent:
+ if (destroy_parent)
+ dput(parent);
+out_drop_write:
+ mnt_drop_write_file(file);
+out:
+ kfree(vol_args2);
+ kfree(vol_args);
+ return err;
+}
+
+static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_ioctl_defrag_range_args range = {0};
+ int ret;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ if (btrfs_root_readonly(root)) {
+ ret = -EROFS;
+ goto out;
+ }
+
+ switch (inode->i_mode & S_IFMT) {
+ case S_IFDIR:
+ if (!capable(CAP_SYS_ADMIN)) {
+ ret = -EPERM;
+ goto out;
+ }
+ ret = btrfs_defrag_root(root);
+ break;
+ case S_IFREG:
+ /*
+ * Note that this does not check the file descriptor for write
+ * access. This prevents defragmenting executables that are
+ * running and allows defrag on files open in read-only mode.
+ */
+ if (!capable(CAP_SYS_ADMIN) &&
+ inode_permission(&nop_mnt_idmap, inode, MAY_WRITE)) {
+ ret = -EPERM;
+ goto out;
+ }
+
+ if (argp) {
+ if (copy_from_user(&range, argp, sizeof(range))) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (range.flags & ~BTRFS_DEFRAG_RANGE_FLAGS_SUPP) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+ /* compression requires us to start the IO */
+ if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
+ range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
+ range.extent_thresh = (u32)-1;
+ }
+ } else {
+ /* the rest are all set to zero by kzalloc */
+ range.len = (u64)-1;
+ }
+ ret = btrfs_defrag_file(file_inode(file), &file->f_ra,
+ &range, BTRFS_OLDEST_GENERATION, 0);
+ if (ret > 0)
+ ret = 0;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+out:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
+{
+ struct btrfs_ioctl_vol_args *vol_args;
+ bool restore_op = false;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
+ btrfs_err(fs_info, "device add not supported on extent tree v2 yet");
+ return -EINVAL;
+ }
+
+ if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) {
+ if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD))
+ return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
+
+ /*
+ * We can do the device add because we have a paused balanced,
+ * change the exclusive op type and remember we should bring
+ * back the paused balance
+ */
+ fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD;
+ btrfs_exclop_start_unlock(fs_info);
+ restore_op = true;
+ }
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args)) {
+ ret = PTR_ERR(vol_args);
+ goto out;
+ }
+
+ vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+ ret = btrfs_init_new_device(fs_info, vol_args->name);
+
+ if (!ret)
+ btrfs_info(fs_info, "disk added %s", vol_args->name);
+
+ kfree(vol_args);
+out:
+ if (restore_op)
+ btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
+ else
+ btrfs_exclop_finish(fs_info);
+ return ret;
+}
+
+static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_ioctl_vol_args_v2 *vol_args;
+ struct block_device *bdev = NULL;
+ void *holder;
+ int ret;
+ bool cancel = false;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+
+ if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
+ if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
+ args.devid = vol_args->devid;
+ } else if (!strcmp("cancel", vol_args->name)) {
+ cancel = true;
+ } else {
+ ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
+ if (ret)
+ goto out;
+ }
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ goto out;
+
+ ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
+ cancel);
+ if (ret)
+ goto err_drop;
+
+ /* Exclusive operation is now claimed */
+ ret = btrfs_rm_device(fs_info, &args, &bdev, &holder);
+
+ btrfs_exclop_finish(fs_info);
+
+ if (!ret) {
+ if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
+ btrfs_info(fs_info, "device deleted: id %llu",
+ vol_args->devid);
+ else
+ btrfs_info(fs_info, "device deleted: %s",
+ vol_args->name);
+ }
+err_drop:
+ mnt_drop_write_file(file);
+ if (bdev)
+ blkdev_put(bdev, holder);
+out:
+ btrfs_put_dev_args_from_path(&args);
+ kfree(vol_args);
+ return ret;
+}
+
+static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_ioctl_vol_args *vol_args;
+ struct block_device *bdev = NULL;
+ void *holder;
+ int ret;
+ bool cancel = false;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+
+ vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+ if (!strcmp("cancel", vol_args->name)) {
+ cancel = true;
+ } else {
+ ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
+ if (ret)
+ goto out;
+ }
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ goto out;
+
+ ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
+ cancel);
+ if (ret == 0) {
+ ret = btrfs_rm_device(fs_info, &args, &bdev, &holder);
+ if (!ret)
+ btrfs_info(fs_info, "disk deleted %s", vol_args->name);
+ btrfs_exclop_finish(fs_info);
+ }
+
+ mnt_drop_write_file(file);
+ if (bdev)
+ blkdev_put(bdev, holder);
+out:
+ btrfs_put_dev_args_from_path(&args);
+ kfree(vol_args);
+ return ret;
+}
+
+static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_ioctl_fs_info_args *fi_args;
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ u64 flags_in;
+ int ret = 0;
+
+ fi_args = memdup_user(arg, sizeof(*fi_args));
+ if (IS_ERR(fi_args))
+ return PTR_ERR(fi_args);
+
+ flags_in = fi_args->flags;
+ memset(fi_args, 0, sizeof(*fi_args));
+
+ rcu_read_lock();
+ fi_args->num_devices = fs_devices->num_devices;
+
+ list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
+ if (device->devid > fi_args->max_id)
+ fi_args->max_id = device->devid;
+ }
+ rcu_read_unlock();
+
+ memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
+ fi_args->nodesize = fs_info->nodesize;
+ fi_args->sectorsize = fs_info->sectorsize;
+ fi_args->clone_alignment = fs_info->sectorsize;
+
+ if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
+ fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
+ fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
+ fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
+ }
+
+ if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
+ fi_args->generation = fs_info->generation;
+ fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
+ }
+
+ if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
+ memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
+ sizeof(fi_args->metadata_uuid));
+ fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
+ }
+
+ if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
+ ret = -EFAULT;
+
+ kfree(fi_args);
+ return ret;
+}
+
+static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ BTRFS_DEV_LOOKUP_ARGS(args);
+ struct btrfs_ioctl_dev_info_args *di_args;
+ struct btrfs_device *dev;
+ int ret = 0;
+
+ di_args = memdup_user(arg, sizeof(*di_args));
+ if (IS_ERR(di_args))
+ return PTR_ERR(di_args);
+
+ args.devid = di_args->devid;
+ if (!btrfs_is_empty_uuid(di_args->uuid))
+ args.uuid = di_args->uuid;
+
+ rcu_read_lock();
+ dev = btrfs_find_device(fs_info->fs_devices, &args);
+ if (!dev) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ di_args->devid = dev->devid;
+ di_args->bytes_used = btrfs_device_get_bytes_used(dev);
+ di_args->total_bytes = btrfs_device_get_total_bytes(dev);
+ memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
+ memcpy(di_args->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
+ if (dev->name)
+ strscpy(di_args->path, btrfs_dev_name(dev), sizeof(di_args->path));
+ else
+ di_args->path[0] = '\0';
+
+out:
+ rcu_read_unlock();
+ if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
+ ret = -EFAULT;
+
+ kfree(di_args);
+ return ret;
+}
+
+static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_root *new_root;
+ struct btrfs_dir_item *di;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_path *path = NULL;
+ struct btrfs_disk_key disk_key;
+ struct fscrypt_str name = FSTR_INIT("default", 7);
+ u64 objectid = 0;
+ u64 dir_id;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ if (copy_from_user(&objectid, argp, sizeof(objectid))) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ if (!objectid)
+ objectid = BTRFS_FS_TREE_OBJECTID;
+
+ new_root = btrfs_get_fs_root(fs_info, objectid, true);
+ if (IS_ERR(new_root)) {
+ ret = PTR_ERR(new_root);
+ goto out;
+ }
+ if (!is_fstree(new_root->root_key.objectid)) {
+ ret = -ENOENT;
+ goto out_free;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_free;
+ }
+
+ dir_id = btrfs_super_root_dir(fs_info->super_copy);
+ di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
+ dir_id, &name, 1);
+ if (IS_ERR_OR_NULL(di)) {
+ btrfs_release_path(path);
+ btrfs_end_transaction(trans);
+ btrfs_err(fs_info,
+ "Umm, you don't have the default diritem, this isn't going to work");
+ ret = -ENOENT;
+ goto out_free;
+ }
+
+ btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
+ btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
+ btrfs_mark_buffer_dirty(trans, path->nodes[0]);
+ btrfs_release_path(path);
+
+ btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
+ btrfs_end_transaction(trans);
+out_free:
+ btrfs_put_root(new_root);
+ btrfs_free_path(path);
+out:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static void get_block_group_info(struct list_head *groups_list,
+ struct btrfs_ioctl_space_info *space)
+{
+ struct btrfs_block_group *block_group;
+
+ space->total_bytes = 0;
+ space->used_bytes = 0;
+ space->flags = 0;
+ list_for_each_entry(block_group, groups_list, list) {
+ space->flags = block_group->flags;
+ space->total_bytes += block_group->length;
+ space->used_bytes += block_group->used;
+ }
+}
+
+static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_ioctl_space_args space_args = { 0 };
+ struct btrfs_ioctl_space_info space;
+ struct btrfs_ioctl_space_info *dest;
+ struct btrfs_ioctl_space_info *dest_orig;
+ struct btrfs_ioctl_space_info __user *user_dest;
+ struct btrfs_space_info *info;
+ static const u64 types[] = {
+ BTRFS_BLOCK_GROUP_DATA,
+ BTRFS_BLOCK_GROUP_SYSTEM,
+ BTRFS_BLOCK_GROUP_METADATA,
+ BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
+ };
+ int num_types = 4;
+ int alloc_size;
+ int ret = 0;
+ u64 slot_count = 0;
+ int i, c;
+
+ if (copy_from_user(&space_args,
+ (struct btrfs_ioctl_space_args __user *)arg,
+ sizeof(space_args)))
+ return -EFAULT;
+
+ for (i = 0; i < num_types; i++) {
+ struct btrfs_space_info *tmp;
+
+ info = NULL;
+ list_for_each_entry(tmp, &fs_info->space_info, list) {
+ if (tmp->flags == types[i]) {
+ info = tmp;
+ break;
+ }
+ }
+
+ if (!info)
+ continue;
+
+ down_read(&info->groups_sem);
+ for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
+ if (!list_empty(&info->block_groups[c]))
+ slot_count++;
+ }
+ up_read(&info->groups_sem);
+ }
+
+ /*
+ * Global block reserve, exported as a space_info
+ */
+ slot_count++;
+
+ /* space_slots == 0 means they are asking for a count */
+ if (space_args.space_slots == 0) {
+ space_args.total_spaces = slot_count;
+ goto out;
+ }
+
+ slot_count = min_t(u64, space_args.space_slots, slot_count);
+
+ alloc_size = sizeof(*dest) * slot_count;
+
+ /* we generally have at most 6 or so space infos, one for each raid
+ * level. So, a whole page should be more than enough for everyone
+ */
+ if (alloc_size > PAGE_SIZE)
+ return -ENOMEM;
+
+ space_args.total_spaces = 0;
+ dest = kmalloc(alloc_size, GFP_KERNEL);
+ if (!dest)
+ return -ENOMEM;
+ dest_orig = dest;
+
+ /* now we have a buffer to copy into */
+ for (i = 0; i < num_types; i++) {
+ struct btrfs_space_info *tmp;
+
+ if (!slot_count)
+ break;
+
+ info = NULL;
+ list_for_each_entry(tmp, &fs_info->space_info, list) {
+ if (tmp->flags == types[i]) {
+ info = tmp;
+ break;
+ }
+ }
+
+ if (!info)
+ continue;
+ down_read(&info->groups_sem);
+ for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
+ if (!list_empty(&info->block_groups[c])) {
+ get_block_group_info(&info->block_groups[c],
+ &space);
+ memcpy(dest, &space, sizeof(space));
+ dest++;
+ space_args.total_spaces++;
+ slot_count--;
+ }
+ if (!slot_count)
+ break;
+ }
+ up_read(&info->groups_sem);
+ }
+
+ /*
+ * Add global block reserve
+ */
+ if (slot_count) {
+ struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
+
+ spin_lock(&block_rsv->lock);
+ space.total_bytes = block_rsv->size;
+ space.used_bytes = block_rsv->size - block_rsv->reserved;
+ spin_unlock(&block_rsv->lock);
+ space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
+ memcpy(dest, &space, sizeof(space));
+ space_args.total_spaces++;
+ }
+
+ user_dest = (struct btrfs_ioctl_space_info __user *)
+ (arg + sizeof(struct btrfs_ioctl_space_args));
+
+ if (copy_to_user(user_dest, dest_orig, alloc_size))
+ ret = -EFAULT;
+
+ kfree(dest_orig);
+out:
+ if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
+ ret = -EFAULT;
+
+ return ret;
+}
+
+static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
+ void __user *argp)
+{
+ struct btrfs_trans_handle *trans;
+ u64 transid;
+
+ /*
+ * Start orphan cleanup here for the given root in case it hasn't been
+ * started already by other means. Errors are handled in the other
+ * functions during transaction commit.
+ */
+ btrfs_orphan_cleanup(root);
+
+ trans = btrfs_attach_transaction_barrier(root);
+ if (IS_ERR(trans)) {
+ if (PTR_ERR(trans) != -ENOENT)
+ return PTR_ERR(trans);
+
+ /* No running transaction, don't bother */
+ transid = root->fs_info->last_trans_committed;
+ goto out;
+ }
+ transid = trans->transid;
+ btrfs_commit_transaction_async(trans);
+out:
+ if (argp)
+ if (copy_to_user(argp, &transid, sizeof(transid)))
+ return -EFAULT;
+ return 0;
+}
+
+static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
+ void __user *argp)
+{
+ /* By default wait for the current transaction. */
+ u64 transid = 0;
+
+ if (argp)
+ if (copy_from_user(&transid, argp, sizeof(transid)))
+ return -EFAULT;
+
+ return btrfs_wait_for_commit(fs_info, transid);
+}
+
+static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
+ struct btrfs_ioctl_scrub_args *sa;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
+ btrfs_err(fs_info, "scrub is not supported on extent tree v2 yet");
+ return -EINVAL;
+ }
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa))
+ return PTR_ERR(sa);
+
+ if (sa->flags & ~BTRFS_SCRUB_SUPPORTED_FLAGS) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
+ ret = mnt_want_write_file(file);
+ if (ret)
+ goto out;
+ }
+
+ ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
+ &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
+ 0);
+
+ /*
+ * Copy scrub args to user space even if btrfs_scrub_dev() returned an
+ * error. This is important as it allows user space to know how much
+ * progress scrub has done. For example, if scrub is canceled we get
+ * -ECANCELED from btrfs_scrub_dev() and return that error back to user
+ * space. Later user space can inspect the progress from the structure
+ * btrfs_ioctl_scrub_args and resume scrub from where it left off
+ * previously (btrfs-progs does this).
+ * If we fail to copy the btrfs_ioctl_scrub_args structure to user space
+ * then return -EFAULT to signal the structure was not copied or it may
+ * be corrupt and unreliable due to a partial copy.
+ */
+ if (copy_to_user(arg, sa, sizeof(*sa)))
+ ret = -EFAULT;
+
+ if (!(sa->flags & BTRFS_SCRUB_READONLY))
+ mnt_drop_write_file(file);
+out:
+ kfree(sa);
+ return ret;
+}
+
+static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ return btrfs_scrub_cancel(fs_info);
+}
+
+static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_ioctl_scrub_args *sa;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa))
+ return PTR_ERR(sa);
+
+ ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
+
+ if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
+ ret = -EFAULT;
+
+ kfree(sa);
+ return ret;
+}
+
+static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_ioctl_get_dev_stats *sa;
+ int ret;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa))
+ return PTR_ERR(sa);
+
+ if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
+ kfree(sa);
+ return -EPERM;
+ }
+
+ ret = btrfs_get_dev_stats(fs_info, sa);
+
+ if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
+ ret = -EFAULT;
+
+ kfree(sa);
+ return ret;
+}
+
+static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_ioctl_dev_replace_args *p;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
+ btrfs_err(fs_info, "device replace not supported on extent tree v2 yet");
+ return -EINVAL;
+ }
+
+ p = memdup_user(arg, sizeof(*p));
+ if (IS_ERR(p))
+ return PTR_ERR(p);
+
+ switch (p->cmd) {
+ case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
+ if (sb_rdonly(fs_info->sb)) {
+ ret = -EROFS;
+ goto out;
+ }
+ if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) {
+ ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
+ } else {
+ ret = btrfs_dev_replace_by_ioctl(fs_info, p);
+ btrfs_exclop_finish(fs_info);
+ }
+ break;
+ case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
+ btrfs_dev_replace_status(fs_info, p);
+ ret = 0;
+ break;
+ case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
+ p->result = btrfs_dev_replace_cancel(fs_info);
+ ret = 0;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
+ ret = -EFAULT;
+out:
+ kfree(p);
+ return ret;
+}
+
+static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
+{
+ int ret = 0;
+ int i;
+ u64 rel_ptr;
+ int size;
+ struct btrfs_ioctl_ino_path_args *ipa = NULL;
+ struct inode_fs_paths *ipath = NULL;
+ struct btrfs_path *path;
+
+ if (!capable(CAP_DAC_READ_SEARCH))
+ return -EPERM;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ipa = memdup_user(arg, sizeof(*ipa));
+ if (IS_ERR(ipa)) {
+ ret = PTR_ERR(ipa);
+ ipa = NULL;
+ goto out;
+ }
+
+ size = min_t(u32, ipa->size, 4096);
+ ipath = init_ipath(size, root, path);
+ if (IS_ERR(ipath)) {
+ ret = PTR_ERR(ipath);
+ ipath = NULL;
+ goto out;
+ }
+
+ ret = paths_from_inode(ipa->inum, ipath);
+ if (ret < 0)
+ goto out;
+
+ for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
+ rel_ptr = ipath->fspath->val[i] -
+ (u64)(unsigned long)ipath->fspath->val;
+ ipath->fspath->val[i] = rel_ptr;
+ }
+
+ btrfs_free_path(path);
+ path = NULL;
+ ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
+ ipath->fspath, size);
+ if (ret) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+out:
+ btrfs_free_path(path);
+ free_ipath(ipath);
+ kfree(ipa);
+
+ return ret;
+}
+
+static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
+ void __user *arg, int version)
+{
+ int ret = 0;
+ int size;
+ struct btrfs_ioctl_logical_ino_args *loi;
+ struct btrfs_data_container *inodes = NULL;
+ struct btrfs_path *path = NULL;
+ bool ignore_offset;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ loi = memdup_user(arg, sizeof(*loi));
+ if (IS_ERR(loi))
+ return PTR_ERR(loi);
+
+ if (version == 1) {
+ ignore_offset = false;
+ size = min_t(u32, loi->size, SZ_64K);
+ } else {
+ /* All reserved bits must be 0 for now */
+ if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
+ ret = -EINVAL;
+ goto out_loi;
+ }
+ /* Only accept flags we have defined so far */
+ if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
+ ret = -EINVAL;
+ goto out_loi;
+ }
+ ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
+ size = min_t(u32, loi->size, SZ_16M);
+ }
+
+ inodes = init_data_container(size);
+ if (IS_ERR(inodes)) {
+ ret = PTR_ERR(inodes);
+ goto out_loi;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
+ inodes, ignore_offset);
+ btrfs_free_path(path);
+ if (ret == -EINVAL)
+ ret = -ENOENT;
+ if (ret < 0)
+ goto out;
+
+ ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
+ size);
+ if (ret)
+ ret = -EFAULT;
+
+out:
+ kvfree(inodes);
+out_loi:
+ kfree(loi);
+
+ return ret;
+}
+
+void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
+ struct btrfs_ioctl_balance_args *bargs)
+{
+ struct btrfs_balance_control *bctl = fs_info->balance_ctl;
+
+ bargs->flags = bctl->flags;
+
+ if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
+ bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
+ if (atomic_read(&fs_info->balance_pause_req))
+ bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
+ if (atomic_read(&fs_info->balance_cancel_req))
+ bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
+
+ memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
+ memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
+ memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
+
+ spin_lock(&fs_info->balance_lock);
+ memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
+ spin_unlock(&fs_info->balance_lock);
+}
+
+/*
+ * Try to acquire fs_info::balance_mutex as well as set BTRFS_EXLCOP_BALANCE as
+ * required.
+ *
+ * @fs_info: the filesystem
+ * @excl_acquired: ptr to boolean value which is set to false in case balance
+ * is being resumed
+ *
+ * Return 0 on success in which case both fs_info::balance is acquired as well
+ * as exclusive ops are blocked. In case of failure return an error code.
+ */
+static int btrfs_try_lock_balance(struct btrfs_fs_info *fs_info, bool *excl_acquired)
+{
+ int ret;
+
+ /*
+ * Exclusive operation is locked. Three possibilities:
+ * (1) some other op is running
+ * (2) balance is running
+ * (3) balance is paused -- special case (think resume)
+ */
+ while (1) {
+ if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
+ *excl_acquired = true;
+ mutex_lock(&fs_info->balance_mutex);
+ return 0;
+ }
+
+ mutex_lock(&fs_info->balance_mutex);
+ if (fs_info->balance_ctl) {
+ /* This is either (2) or (3) */
+ if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
+ /* This is (2) */
+ ret = -EINPROGRESS;
+ goto out_failure;
+
+ } 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 &&
+ !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
+ /* This is (3) */
+ *excl_acquired = false;
+ return 0;
+ }
+ }
+ } else {
+ /* This is (1) */
+ ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
+ goto out_failure;
+ }
+
+ mutex_unlock(&fs_info->balance_mutex);
+ }
+
+out_failure:
+ mutex_unlock(&fs_info->balance_mutex);
+ *excl_acquired = false;
+ return ret;
+}
+
+static long btrfs_ioctl_balance(struct file *file, void __user *arg)
+{
+ struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_ioctl_balance_args *bargs;
+ struct btrfs_balance_control *bctl;
+ bool need_unlock = true;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ bargs = memdup_user(arg, sizeof(*bargs));
+ if (IS_ERR(bargs)) {
+ ret = PTR_ERR(bargs);
+ bargs = NULL;
+ goto out;
+ }
+
+ ret = btrfs_try_lock_balance(fs_info, &need_unlock);
+ if (ret)
+ goto out;
+
+ lockdep_assert_held(&fs_info->balance_mutex);
+
+ if (bargs->flags & BTRFS_BALANCE_RESUME) {
+ if (!fs_info->balance_ctl) {
+ ret = -ENOTCONN;
+ goto out_unlock;
+ }
+
+ bctl = fs_info->balance_ctl;
+ spin_lock(&fs_info->balance_lock);
+ bctl->flags |= BTRFS_BALANCE_RESUME;
+ spin_unlock(&fs_info->balance_lock);
+ btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE);
+
+ goto do_balance;
+ }
+
+ if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ if (fs_info->balance_ctl) {
+ ret = -EINPROGRESS;
+ goto out_unlock;
+ }
+
+ bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
+ if (!bctl) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+
+ memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
+ memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
+ memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
+
+ bctl->flags = bargs->flags;
+do_balance:
+ /*
+ * Ownership of bctl and exclusive operation goes to btrfs_balance.
+ * bctl is freed in reset_balance_state, or, if restriper was paused
+ * all the way until unmount, in free_fs_info. The flag should be
+ * cleared after reset_balance_state.
+ */
+ need_unlock = false;
+
+ ret = btrfs_balance(fs_info, bctl, bargs);
+ bctl = NULL;
+
+ if (ret == 0 || ret == -ECANCELED) {
+ if (copy_to_user(arg, bargs, sizeof(*bargs)))
+ ret = -EFAULT;
+ }
+
+ kfree(bctl);
+out_unlock:
+ mutex_unlock(&fs_info->balance_mutex);
+ if (need_unlock)
+ btrfs_exclop_finish(fs_info);
+out:
+ mnt_drop_write_file(file);
+ kfree(bargs);
+ return ret;
+}
+
+static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ switch (cmd) {
+ case BTRFS_BALANCE_CTL_PAUSE:
+ return btrfs_pause_balance(fs_info);
+ case BTRFS_BALANCE_CTL_CANCEL:
+ return btrfs_cancel_balance(fs_info);
+ }
+
+ return -EINVAL;
+}
+
+static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_ioctl_balance_args *bargs;
+ int ret = 0;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ mutex_lock(&fs_info->balance_mutex);
+ if (!fs_info->balance_ctl) {
+ ret = -ENOTCONN;
+ goto out;
+ }
+
+ bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
+ if (!bargs) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ btrfs_update_ioctl_balance_args(fs_info, bargs);
+
+ if (copy_to_user(arg, bargs, sizeof(*bargs)))
+ ret = -EFAULT;
+
+ kfree(bargs);
+out:
+ mutex_unlock(&fs_info->balance_mutex);
+ return ret;
+}
+
+static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_ioctl_quota_ctl_args *sa;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa)) {
+ ret = PTR_ERR(sa);
+ goto drop_write;
+ }
+
+ down_write(&fs_info->subvol_sem);
+
+ switch (sa->cmd) {
+ case BTRFS_QUOTA_CTL_ENABLE:
+ ret = btrfs_quota_enable(fs_info);
+ break;
+ case BTRFS_QUOTA_CTL_DISABLE:
+ ret = btrfs_quota_disable(fs_info);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ kfree(sa);
+ up_write(&fs_info->subvol_sem);
+drop_write:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_ioctl_qgroup_assign_args *sa;
+ struct btrfs_trans_handle *trans;
+ int ret;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa)) {
+ ret = PTR_ERR(sa);
+ goto drop_write;
+ }
+
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out;
+ }
+
+ if (sa->assign) {
+ ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
+ } else {
+ ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
+ }
+
+ /* update qgroup status and info */
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ err = btrfs_run_qgroups(trans);
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+ if (err < 0)
+ btrfs_handle_fs_error(fs_info, err,
+ "failed to update qgroup status and info");
+ err = btrfs_end_transaction(trans);
+ if (err && !ret)
+ ret = err;
+
+out:
+ kfree(sa);
+drop_write:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_ioctl_qgroup_create_args *sa;
+ struct btrfs_trans_handle *trans;
+ int ret;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa)) {
+ ret = PTR_ERR(sa);
+ goto drop_write;
+ }
+
+ if (!sa->qgroupid) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out;
+ }
+
+ if (sa->create) {
+ ret = btrfs_create_qgroup(trans, sa->qgroupid);
+ } else {
+ ret = btrfs_remove_qgroup(trans, sa->qgroupid);
+ }
+
+ err = btrfs_end_transaction(trans);
+ if (err && !ret)
+ ret = err;
+
+out:
+ kfree(sa);
+drop_write:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_ioctl_qgroup_limit_args *sa;
+ struct btrfs_trans_handle *trans;
+ int ret;
+ int err;
+ u64 qgroupid;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa)) {
+ ret = PTR_ERR(sa);
+ goto drop_write;
+ }
+
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out;
+ }
+
+ qgroupid = sa->qgroupid;
+ if (!qgroupid) {
+ /* take the current subvol as qgroup */
+ qgroupid = root->root_key.objectid;
+ }
+
+ ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
+
+ err = btrfs_end_transaction(trans);
+ if (err && !ret)
+ ret = err;
+
+out:
+ kfree(sa);
+drop_write:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_ioctl_quota_rescan_args *qsa;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ qsa = memdup_user(arg, sizeof(*qsa));
+ if (IS_ERR(qsa)) {
+ ret = PTR_ERR(qsa);
+ goto drop_write;
+ }
+
+ if (qsa->flags) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = btrfs_qgroup_rescan(fs_info);
+
+out:
+ kfree(qsa);
+drop_write:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_ioctl_quota_rescan_args qsa = {0};
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
+ qsa.flags = 1;
+ qsa.progress = fs_info->qgroup_rescan_progress.objectid;
+ }
+
+ if (copy_to_user(arg, &qsa, sizeof(qsa)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ return btrfs_qgroup_wait_for_completion(fs_info, true);
+}
+
+static long _btrfs_ioctl_set_received_subvol(struct file *file,
+ struct mnt_idmap *idmap,
+ struct btrfs_ioctl_received_subvol_args *sa)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_root_item *root_item = &root->root_item;
+ struct btrfs_trans_handle *trans;
+ struct timespec64 ct = current_time(inode);
+ int ret = 0;
+ int received_uuid_changed;
+
+ if (!inode_owner_or_capable(idmap, inode))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret < 0)
+ return ret;
+
+ down_write(&fs_info->subvol_sem);
+
+ if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (btrfs_root_readonly(root)) {
+ ret = -EROFS;
+ goto out;
+ }
+
+ /*
+ * 1 - root item
+ * 2 - uuid items (received uuid + subvol uuid)
+ */
+ trans = btrfs_start_transaction(root, 3);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ trans = NULL;
+ goto out;
+ }
+
+ sa->rtransid = trans->transid;
+ sa->rtime.sec = ct.tv_sec;
+ sa->rtime.nsec = ct.tv_nsec;
+
+ received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
+ BTRFS_UUID_SIZE);
+ if (received_uuid_changed &&
+ !btrfs_is_empty_uuid(root_item->received_uuid)) {
+ ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
+ BTRFS_UUID_KEY_RECEIVED_SUBVOL,
+ root->root_key.objectid);
+ if (ret && ret != -ENOENT) {
+ btrfs_abort_transaction(trans, ret);
+ btrfs_end_transaction(trans);
+ goto out;
+ }
+ }
+ memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
+ btrfs_set_root_stransid(root_item, sa->stransid);
+ btrfs_set_root_rtransid(root_item, sa->rtransid);
+ btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
+ btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
+ btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
+ btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
+
+ ret = btrfs_update_root(trans, fs_info->tree_root,
+ &root->root_key, &root->root_item);
+ if (ret < 0) {
+ btrfs_end_transaction(trans);
+ goto out;
+ }
+ if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
+ ret = btrfs_uuid_tree_add(trans, sa->uuid,
+ BTRFS_UUID_KEY_RECEIVED_SUBVOL,
+ root->root_key.objectid);
+ if (ret < 0 && ret != -EEXIST) {
+ btrfs_abort_transaction(trans, ret);
+ btrfs_end_transaction(trans);
+ goto out;
+ }
+ }
+ ret = btrfs_commit_transaction(trans);
+out:
+ up_write(&fs_info->subvol_sem);
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+#ifdef CONFIG_64BIT
+static long btrfs_ioctl_set_received_subvol_32(struct file *file,
+ void __user *arg)
+{
+ struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
+ struct btrfs_ioctl_received_subvol_args *args64 = NULL;
+ int ret = 0;
+
+ args32 = memdup_user(arg, sizeof(*args32));
+ if (IS_ERR(args32))
+ return PTR_ERR(args32);
+
+ args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
+ if (!args64) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
+ args64->stransid = args32->stransid;
+ args64->rtransid = args32->rtransid;
+ args64->stime.sec = args32->stime.sec;
+ args64->stime.nsec = args32->stime.nsec;
+ args64->rtime.sec = args32->rtime.sec;
+ args64->rtime.nsec = args32->rtime.nsec;
+ args64->flags = args32->flags;
+
+ ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), args64);
+ if (ret)
+ goto out;
+
+ memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
+ args32->stransid = args64->stransid;
+ args32->rtransid = args64->rtransid;
+ args32->stime.sec = args64->stime.sec;
+ args32->stime.nsec = args64->stime.nsec;
+ args32->rtime.sec = args64->rtime.sec;
+ args32->rtime.nsec = args64->rtime.nsec;
+ args32->flags = args64->flags;
+
+ ret = copy_to_user(arg, args32, sizeof(*args32));
+ if (ret)
+ ret = -EFAULT;
+
+out:
+ kfree(args32);
+ kfree(args64);
+ return ret;
+}
+#endif
+
+static long btrfs_ioctl_set_received_subvol(struct file *file,
+ void __user *arg)
+{
+ struct btrfs_ioctl_received_subvol_args *sa = NULL;
+ int ret = 0;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa))
+ return PTR_ERR(sa);
+
+ ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), sa);
+
+ if (ret)
+ goto out;
+
+ ret = copy_to_user(arg, sa, sizeof(*sa));
+ if (ret)
+ ret = -EFAULT;
+
+out:
+ kfree(sa);
+ return ret;
+}
+
+static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ size_t len;
+ int ret;
+ char label[BTRFS_LABEL_SIZE];
+
+ spin_lock(&fs_info->super_lock);
+ memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
+ spin_unlock(&fs_info->super_lock);
+
+ len = strnlen(label, BTRFS_LABEL_SIZE);
+
+ if (len == BTRFS_LABEL_SIZE) {
+ btrfs_warn(fs_info,
+ "label is too long, return the first %zu bytes",
+ --len);
+ }
+
+ ret = copy_to_user(arg, label, len);
+
+ return ret ? -EFAULT : 0;
+}
+
+static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_super_block *super_block = fs_info->super_copy;
+ struct btrfs_trans_handle *trans;
+ char label[BTRFS_LABEL_SIZE];
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (copy_from_user(label, arg, sizeof(label)))
+ return -EFAULT;
+
+ if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
+ btrfs_err(fs_info,
+ "unable to set label with more than %d bytes",
+ BTRFS_LABEL_SIZE - 1);
+ return -EINVAL;
+ }
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_unlock;
+ }
+
+ spin_lock(&fs_info->super_lock);
+ strcpy(super_block->label, label);
+ spin_unlock(&fs_info->super_lock);
+ ret = btrfs_commit_transaction(trans);
+
+out_unlock:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+#define INIT_FEATURE_FLAGS(suffix) \
+ { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
+ .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
+ .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
+
+int btrfs_ioctl_get_supported_features(void __user *arg)
+{
+ static const struct btrfs_ioctl_feature_flags features[3] = {
+ INIT_FEATURE_FLAGS(SUPP),
+ INIT_FEATURE_FLAGS(SAFE_SET),
+ INIT_FEATURE_FLAGS(SAFE_CLEAR)
+ };
+
+ if (copy_to_user(arg, &features, sizeof(features)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,
+ void __user *arg)
+{
+ struct btrfs_super_block *super_block = fs_info->super_copy;
+ struct btrfs_ioctl_feature_flags features;
+
+ features.compat_flags = btrfs_super_compat_flags(super_block);
+ features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
+ features.incompat_flags = btrfs_super_incompat_flags(super_block);
+
+ if (copy_to_user(arg, &features, sizeof(features)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int check_feature_bits(struct btrfs_fs_info *fs_info,
+ enum btrfs_feature_set set,
+ u64 change_mask, u64 flags, u64 supported_flags,
+ u64 safe_set, u64 safe_clear)
+{
+ const char *type = btrfs_feature_set_name(set);
+ char *names;
+ u64 disallowed, unsupported;
+ u64 set_mask = flags & change_mask;
+ u64 clear_mask = ~flags & change_mask;
+
+ unsupported = set_mask & ~supported_flags;
+ if (unsupported) {
+ names = btrfs_printable_features(set, unsupported);
+ if (names) {
+ btrfs_warn(fs_info,
+ "this kernel does not support the %s feature bit%s",
+ names, strchr(names, ',') ? "s" : "");
+ kfree(names);
+ } else
+ btrfs_warn(fs_info,
+ "this kernel does not support %s bits 0x%llx",
+ type, unsupported);
+ return -EOPNOTSUPP;
+ }
+
+ disallowed = set_mask & ~safe_set;
+ if (disallowed) {
+ names = btrfs_printable_features(set, disallowed);
+ if (names) {
+ btrfs_warn(fs_info,
+ "can't set the %s feature bit%s while mounted",
+ names, strchr(names, ',') ? "s" : "");
+ kfree(names);
+ } else
+ btrfs_warn(fs_info,
+ "can't set %s bits 0x%llx while mounted",
+ type, disallowed);
+ return -EPERM;
+ }
+
+ disallowed = clear_mask & ~safe_clear;
+ if (disallowed) {
+ names = btrfs_printable_features(set, disallowed);
+ if (names) {
+ btrfs_warn(fs_info,
+ "can't clear the %s feature bit%s while mounted",
+ names, strchr(names, ',') ? "s" : "");
+ kfree(names);
+ } else
+ btrfs_warn(fs_info,
+ "can't clear %s bits 0x%llx while mounted",
+ type, disallowed);
+ return -EPERM;
+ }
+
+ return 0;
+}
+
+#define check_feature(fs_info, change_mask, flags, mask_base) \
+check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
+ BTRFS_FEATURE_ ## mask_base ## _SUPP, \
+ BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
+ BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
+
+static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_super_block *super_block = fs_info->super_copy;
+ struct btrfs_ioctl_feature_flags flags[2];
+ struct btrfs_trans_handle *trans;
+ u64 newflags;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (copy_from_user(flags, arg, sizeof(flags)))
+ return -EFAULT;
+
+ /* Nothing to do */
+ if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
+ !flags[0].incompat_flags)
+ return 0;
+
+ ret = check_feature(fs_info, flags[0].compat_flags,
+ flags[1].compat_flags, COMPAT);
+ if (ret)
+ return ret;
+
+ ret = check_feature(fs_info, flags[0].compat_ro_flags,
+ flags[1].compat_ro_flags, COMPAT_RO);
+ if (ret)
+ return ret;
+
+ ret = check_feature(fs_info, flags[0].incompat_flags,
+ flags[1].incompat_flags, INCOMPAT);
+ if (ret)
+ return ret;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_drop_write;
+ }
+
+ spin_lock(&fs_info->super_lock);
+ newflags = btrfs_super_compat_flags(super_block);
+ newflags |= flags[0].compat_flags & flags[1].compat_flags;
+ newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
+ btrfs_set_super_compat_flags(super_block, newflags);
+
+ newflags = btrfs_super_compat_ro_flags(super_block);
+ newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
+ newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
+ btrfs_set_super_compat_ro_flags(super_block, newflags);
+
+ newflags = btrfs_super_incompat_flags(super_block);
+ newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
+ newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
+ btrfs_set_super_incompat_flags(super_block, newflags);
+ spin_unlock(&fs_info->super_lock);
+
+ ret = btrfs_commit_transaction(trans);
+out_drop_write:
+ mnt_drop_write_file(file);
+
+ return ret;
+}
+
+static int _btrfs_ioctl_send(struct inode *inode, void __user *argp, bool compat)
+{
+ struct btrfs_ioctl_send_args *arg;
+ int ret;
+
+ if (compat) {
+#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
+ struct btrfs_ioctl_send_args_32 args32 = { 0 };
+
+ ret = copy_from_user(&args32, argp, sizeof(args32));
+ if (ret)
+ return -EFAULT;
+ arg = kzalloc(sizeof(*arg), GFP_KERNEL);
+ if (!arg)
+ return -ENOMEM;
+ arg->send_fd = args32.send_fd;
+ arg->clone_sources_count = args32.clone_sources_count;
+ arg->clone_sources = compat_ptr(args32.clone_sources);
+ arg->parent_root = args32.parent_root;
+ arg->flags = args32.flags;
+ arg->version = args32.version;
+ memcpy(arg->reserved, args32.reserved,
+ sizeof(args32.reserved));
+#else
+ return -ENOTTY;
+#endif
+ } else {
+ arg = memdup_user(argp, sizeof(*arg));
+ if (IS_ERR(arg))
+ return PTR_ERR(arg);
+ }
+ ret = btrfs_ioctl_send(inode, arg);
+ kfree(arg);
+ return ret;
+}
+
+static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp,
+ bool compat)
+{
+ struct btrfs_ioctl_encoded_io_args args = { 0 };
+ size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args,
+ flags);
+ size_t copy_end;
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ loff_t pos;
+ struct kiocb kiocb;
+ ssize_t ret;
+
+ if (!capable(CAP_SYS_ADMIN)) {
+ ret = -EPERM;
+ goto out_acct;
+ }
+
+ if (compat) {
+#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
+ struct btrfs_ioctl_encoded_io_args_32 args32;
+
+ copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32,
+ flags);
+ if (copy_from_user(&args32, argp, copy_end)) {
+ ret = -EFAULT;
+ goto out_acct;
+ }
+ args.iov = compat_ptr(args32.iov);
+ args.iovcnt = args32.iovcnt;
+ args.offset = args32.offset;
+ args.flags = args32.flags;
+#else
+ return -ENOTTY;
+#endif
+ } else {
+ copy_end = copy_end_kernel;
+ if (copy_from_user(&args, argp, copy_end)) {
+ ret = -EFAULT;
+ goto out_acct;
+ }
+ }
+ if (args.flags != 0) {
+ ret = -EINVAL;
+ goto out_acct;
+ }
+
+ ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
+ &iov, &iter);
+ if (ret < 0)
+ goto out_acct;
+
+ if (iov_iter_count(&iter) == 0) {
+ ret = 0;
+ goto out_iov;
+ }
+ pos = args.offset;
+ ret = rw_verify_area(READ, file, &pos, args.len);
+ if (ret < 0)
+ goto out_iov;
+
+ init_sync_kiocb(&kiocb, file);
+ kiocb.ki_pos = pos;
+
+ ret = btrfs_encoded_read(&kiocb, &iter, &args);
+ if (ret >= 0) {
+ fsnotify_access(file);
+ if (copy_to_user(argp + copy_end,
+ (char *)&args + copy_end_kernel,
+ sizeof(args) - copy_end_kernel))
+ ret = -EFAULT;
+ }
+
+out_iov:
+ kfree(iov);
+out_acct:
+ if (ret > 0)
+ add_rchar(current, ret);
+ inc_syscr(current);
+ return ret;
+}
+
+static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool compat)
+{
+ struct btrfs_ioctl_encoded_io_args args;
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ loff_t pos;
+ struct kiocb kiocb;
+ ssize_t ret;
+
+ if (!capable(CAP_SYS_ADMIN)) {
+ ret = -EPERM;
+ goto out_acct;
+ }
+
+ if (!(file->f_mode & FMODE_WRITE)) {
+ ret = -EBADF;
+ goto out_acct;
+ }
+
+ if (compat) {
+#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
+ struct btrfs_ioctl_encoded_io_args_32 args32;
+
+ if (copy_from_user(&args32, argp, sizeof(args32))) {
+ ret = -EFAULT;
+ goto out_acct;
+ }
+ args.iov = compat_ptr(args32.iov);
+ args.iovcnt = args32.iovcnt;
+ args.offset = args32.offset;
+ args.flags = args32.flags;
+ args.len = args32.len;
+ args.unencoded_len = args32.unencoded_len;
+ args.unencoded_offset = args32.unencoded_offset;
+ args.compression = args32.compression;
+ args.encryption = args32.encryption;
+ memcpy(args.reserved, args32.reserved, sizeof(args.reserved));
+#else
+ return -ENOTTY;
+#endif
+ } else {
+ if (copy_from_user(&args, argp, sizeof(args))) {
+ ret = -EFAULT;
+ goto out_acct;
+ }
+ }
+
+ ret = -EINVAL;
+ if (args.flags != 0)
+ goto out_acct;
+ if (memchr_inv(args.reserved, 0, sizeof(args.reserved)))
+ goto out_acct;
+ if (args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE &&
+ args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE)
+ goto out_acct;
+ if (args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES ||
+ args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES)
+ goto out_acct;
+ if (args.unencoded_offset > args.unencoded_len)
+ goto out_acct;
+ if (args.len > args.unencoded_len - args.unencoded_offset)
+ goto out_acct;
+
+ ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
+ &iov, &iter);
+ if (ret < 0)
+ goto out_acct;
+
+ file_start_write(file);
+
+ if (iov_iter_count(&iter) == 0) {
+ ret = 0;
+ goto out_end_write;
+ }
+ pos = args.offset;
+ ret = rw_verify_area(WRITE, file, &pos, args.len);
+ if (ret < 0)
+ goto out_end_write;
+
+ init_sync_kiocb(&kiocb, file);
+ ret = kiocb_set_rw_flags(&kiocb, 0);
+ if (ret)
+ goto out_end_write;
+ kiocb.ki_pos = pos;
+
+ ret = btrfs_do_write_iter(&kiocb, &iter, &args);
+ if (ret > 0)
+ fsnotify_modify(file);
+
+out_end_write:
+ file_end_write(file);
+ kfree(iov);
+out_acct:
+ if (ret > 0)
+ add_wchar(current, ret);
+ inc_syscw(current);
+ return ret;
+}
+
+long btrfs_ioctl(struct file *file, unsigned int
+ cmd, unsigned long arg)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ void __user *argp = (void __user *)arg;
+
+ switch (cmd) {
+ case FS_IOC_GETVERSION:
+ return btrfs_ioctl_getversion(inode, argp);
+ case FS_IOC_GETFSLABEL:
+ return btrfs_ioctl_get_fslabel(fs_info, argp);
+ case FS_IOC_SETFSLABEL:
+ return btrfs_ioctl_set_fslabel(file, argp);
+ case FITRIM:
+ return btrfs_ioctl_fitrim(fs_info, argp);
+ case BTRFS_IOC_SNAP_CREATE:
+ return btrfs_ioctl_snap_create(file, argp, 0);
+ case BTRFS_IOC_SNAP_CREATE_V2:
+ return btrfs_ioctl_snap_create_v2(file, argp, 0);
+ case BTRFS_IOC_SUBVOL_CREATE:
+ return btrfs_ioctl_snap_create(file, argp, 1);
+ case BTRFS_IOC_SUBVOL_CREATE_V2:
+ return btrfs_ioctl_snap_create_v2(file, argp, 1);
+ case BTRFS_IOC_SNAP_DESTROY:
+ return btrfs_ioctl_snap_destroy(file, argp, false);
+ case BTRFS_IOC_SNAP_DESTROY_V2:
+ return btrfs_ioctl_snap_destroy(file, argp, true);
+ case BTRFS_IOC_SUBVOL_GETFLAGS:
+ return btrfs_ioctl_subvol_getflags(inode, argp);
+ case BTRFS_IOC_SUBVOL_SETFLAGS:
+ return btrfs_ioctl_subvol_setflags(file, argp);
+ case BTRFS_IOC_DEFAULT_SUBVOL:
+ return btrfs_ioctl_default_subvol(file, argp);
+ case BTRFS_IOC_DEFRAG:
+ return btrfs_ioctl_defrag(file, NULL);
+ case BTRFS_IOC_DEFRAG_RANGE:
+ return btrfs_ioctl_defrag(file, argp);
+ case BTRFS_IOC_RESIZE:
+ return btrfs_ioctl_resize(file, argp);
+ case BTRFS_IOC_ADD_DEV:
+ return btrfs_ioctl_add_dev(fs_info, argp);
+ case BTRFS_IOC_RM_DEV:
+ return btrfs_ioctl_rm_dev(file, argp);
+ case BTRFS_IOC_RM_DEV_V2:
+ return btrfs_ioctl_rm_dev_v2(file, argp);
+ case BTRFS_IOC_FS_INFO:
+ return btrfs_ioctl_fs_info(fs_info, argp);
+ case BTRFS_IOC_DEV_INFO:
+ return btrfs_ioctl_dev_info(fs_info, argp);
+ case BTRFS_IOC_TREE_SEARCH:
+ return btrfs_ioctl_tree_search(inode, argp);
+ case BTRFS_IOC_TREE_SEARCH_V2:
+ return btrfs_ioctl_tree_search_v2(inode, argp);
+ case BTRFS_IOC_INO_LOOKUP:
+ return btrfs_ioctl_ino_lookup(root, argp);
+ case BTRFS_IOC_INO_PATHS:
+ return btrfs_ioctl_ino_to_path(root, argp);
+ case BTRFS_IOC_LOGICAL_INO:
+ return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
+ case BTRFS_IOC_LOGICAL_INO_V2:
+ return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
+ case BTRFS_IOC_SPACE_INFO:
+ return btrfs_ioctl_space_info(fs_info, argp);
+ case BTRFS_IOC_SYNC: {
+ int ret;
+
+ ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
+ if (ret)
+ return ret;
+ ret = btrfs_sync_fs(inode->i_sb, 1);
+ /*
+ * The transaction thread may want to do more work,
+ * namely it pokes the cleaner kthread that will start
+ * processing uncleaned subvols.
+ */
+ wake_up_process(fs_info->transaction_kthread);
+ return ret;
+ }
+ case BTRFS_IOC_START_SYNC:
+ return btrfs_ioctl_start_sync(root, argp);
+ case BTRFS_IOC_WAIT_SYNC:
+ return btrfs_ioctl_wait_sync(fs_info, argp);
+ case BTRFS_IOC_SCRUB:
+ return btrfs_ioctl_scrub(file, argp);
+ case BTRFS_IOC_SCRUB_CANCEL:
+ return btrfs_ioctl_scrub_cancel(fs_info);
+ case BTRFS_IOC_SCRUB_PROGRESS:
+ return btrfs_ioctl_scrub_progress(fs_info, argp);
+ case BTRFS_IOC_BALANCE_V2:
+ return btrfs_ioctl_balance(file, argp);
+ case BTRFS_IOC_BALANCE_CTL:
+ return btrfs_ioctl_balance_ctl(fs_info, arg);
+ case BTRFS_IOC_BALANCE_PROGRESS:
+ return btrfs_ioctl_balance_progress(fs_info, argp);
+ case BTRFS_IOC_SET_RECEIVED_SUBVOL:
+ return btrfs_ioctl_set_received_subvol(file, argp);
+#ifdef CONFIG_64BIT
+ case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
+ return btrfs_ioctl_set_received_subvol_32(file, argp);
+#endif
+ case BTRFS_IOC_SEND:
+ return _btrfs_ioctl_send(inode, argp, false);
+#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
+ case BTRFS_IOC_SEND_32:
+ return _btrfs_ioctl_send(inode, argp, true);
+#endif
+ case BTRFS_IOC_GET_DEV_STATS:
+ return btrfs_ioctl_get_dev_stats(fs_info, argp);
+ case BTRFS_IOC_QUOTA_CTL:
+ return btrfs_ioctl_quota_ctl(file, argp);
+ case BTRFS_IOC_QGROUP_ASSIGN:
+ return btrfs_ioctl_qgroup_assign(file, argp);
+ case BTRFS_IOC_QGROUP_CREATE:
+ return btrfs_ioctl_qgroup_create(file, argp);
+ case BTRFS_IOC_QGROUP_LIMIT:
+ return btrfs_ioctl_qgroup_limit(file, argp);
+ case BTRFS_IOC_QUOTA_RESCAN:
+ return btrfs_ioctl_quota_rescan(file, argp);
+ case BTRFS_IOC_QUOTA_RESCAN_STATUS:
+ return btrfs_ioctl_quota_rescan_status(fs_info, argp);
+ case BTRFS_IOC_QUOTA_RESCAN_WAIT:
+ return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
+ case BTRFS_IOC_DEV_REPLACE:
+ return btrfs_ioctl_dev_replace(fs_info, argp);
+ case BTRFS_IOC_GET_SUPPORTED_FEATURES:
+ return btrfs_ioctl_get_supported_features(argp);
+ case BTRFS_IOC_GET_FEATURES:
+ return btrfs_ioctl_get_features(fs_info, argp);
+ case BTRFS_IOC_SET_FEATURES:
+ return btrfs_ioctl_set_features(file, argp);
+ case BTRFS_IOC_GET_SUBVOL_INFO:
+ return btrfs_ioctl_get_subvol_info(inode, argp);
+ case BTRFS_IOC_GET_SUBVOL_ROOTREF:
+ return btrfs_ioctl_get_subvol_rootref(root, argp);
+ case BTRFS_IOC_INO_LOOKUP_USER:
+ return btrfs_ioctl_ino_lookup_user(file, argp);
+ case FS_IOC_ENABLE_VERITY:
+ return fsverity_ioctl_enable(file, (const void __user *)argp);
+ case FS_IOC_MEASURE_VERITY:
+ return fsverity_ioctl_measure(file, argp);
+ case BTRFS_IOC_ENCODED_READ:
+ return btrfs_ioctl_encoded_read(file, argp, false);
+ case BTRFS_IOC_ENCODED_WRITE:
+ return btrfs_ioctl_encoded_write(file, argp, false);
+#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
+ case BTRFS_IOC_ENCODED_READ_32:
+ return btrfs_ioctl_encoded_read(file, argp, true);
+ case BTRFS_IOC_ENCODED_WRITE_32:
+ return btrfs_ioctl_encoded_write(file, argp, true);
+#endif
+ }
+
+ return -ENOTTY;
+}
+
+#ifdef CONFIG_COMPAT
+long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ /*
+ * These all access 32-bit values anyway so no further
+ * handling is necessary.
+ */
+ switch (cmd) {
+ case FS_IOC32_GETVERSION:
+ cmd = FS_IOC_GETVERSION;
+ break;
+ }
+
+ return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
+}
+#endif