diff options
| -rw-r--r-- | fs/btrfs/reflink.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c index 6746460fd219..f4ec06b53aa0 100644 --- a/fs/btrfs/reflink.c +++ b/fs/btrfs/reflink.c @@ -834,6 +834,16 @@ static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in, len, remap_flags); } +static bool file_sync_write(const struct file *file) +{ + if (file->f_flags & (__O_SYNC | O_DSYNC)) + return true; + if (IS_SYNC(file_inode(file))) + return true; + + return false; +} + loff_t btrfs_remap_file_range(struct file *src_file, loff_t off, struct file *dst_file, loff_t destoff, loff_t len, unsigned int remap_flags) @@ -871,5 +881,20 @@ out_unlock: unlock_two_nondirectories(src_inode, dst_inode); } + /* + * If either the source or the destination file was opened with O_SYNC, + * O_DSYNC or has the S_SYNC attribute, fsync both the destination and + * source files/ranges, so that after a successful return (0) followed + * by a power failure results in the reflinked data to be readable from + * both files/ranges. + */ + if (ret == 0 && len > 0 && + (file_sync_write(src_file) || file_sync_write(dst_file))) { + ret = btrfs_sync_file(src_file, off, off + len - 1, 0); + if (ret == 0) + ret = btrfs_sync_file(dst_file, destoff, + destoff + len - 1, 0); + } + return ret < 0 ? ret : len; } |