| Message ID | 537fc4aabfc15d24166464fe851958b74cb37082.1719366258.git.wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: detect and fix the ram_bytes mismatch | expand |
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 2cc61c792ee6..e815fefaffe1 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -1306,6 +1306,13 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode, if (compress_type != BTRFS_COMPRESS_NONE) { extent_map_set_compression(em, compress_type); } else { + /* + * Older kernels can create regular non-hole data + * extents with ram_bytes smaller than disk_num_bytes. + * Not a big deal, just always use disk_num_bytes + * for ram_bytes. + */ + em->ram_bytes = em->disk_num_bytes; if (type == BTRFS_FILE_EXTENT_PREALLOC) em->flags |= EXTENT_FLAG_PREALLOC; }
[HICCUP] Kernels can create file extent items with incorrect ram_bytes like this: item 6 key (257 EXTENT_DATA 0) itemoff 15816 itemsize 53 generation 7 type 1 (regular) extent data disk byte 13631488 nr 32768 extent data offset 0 nr 4096 ram 4096 extent compression 0 (none) Thankfully kernel can handle them properly, as in that case ram_bytes is not utilized at all. [ENHANCEMENT] Since the hiccup is not going to cause any data-loss and is only a minor violation of on-disk format, here we only need to ignore the incorrect ram_bytes value, and use the correct one from btrfs_file_extent_item::disk_num_bytes. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/file-item.c | 7 +++++++ 1 file changed, 7 insertions(+)