dd if=/dev/zero of=file bs=4k count=5 xfs_io file -c "fiemap -v 2 16384" file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..31]: 139272..139303 32 0x1000 1: [32..39]: 139304..139311 8 0x1001 xfs_io file -c "fiemap -v 0 16384" file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..31]: 139272..139303 32 0x1000 xfs_io file -c "fiemap -v 0 16385" file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..39]: 139272..139311 40 0x1001

There are two problems: - continuous extent is split to two - FIEMAP_EXTENT_LAST is missing in last extent

The root cause is: if upper boundary of inquiry crosses extent, f2fs_map_blocks() will truncate length of returned extent to F2FS_BYTES_TO_BLK(len), and also, it will stop to query latter extent or hole to make sure current extent is last or not.

In order to fix this issue, once we found an extent locates in the end of inquiry range by f2fs_map_blocks(), we need to expand inquiry range to requiry.

Cc: stable@vger.kernel.org Fixes: 7f63eb77af7b ("f2fs: report unwritten area in f2fs_fiemap") Reported-by: Zhiguo Niu zhiguo.niu@unisoc.com Signed-off-by: Chao Yu chao@kernel.org --- fs/f2fs/data.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 69f1cb0490ee..ee5614324df0 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1896,7 +1896,7 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len) { struct f2fs_map_blocks map; - sector_t start_blk, last_blk; + sector_t start_blk, last_blk, blk_len, max_len; pgoff_t next_pgofs; u64 logical = 0, phys = 0, size = 0; u32 flags = 0; @@ -1940,14 +1940,13 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,

start_blk = F2FS_BYTES_TO_BLK(start); last_blk = F2FS_BYTES_TO_BLK(start + len - 1); - - if (len & F2FS_BLKSIZE_MASK) - len = round_up(len, F2FS_BLKSIZE); + blk_len = last_blk - start_blk + 1; + max_len = F2FS_BYTES_TO_BLK(maxbytes) - start_blk;

next: memset(&map, 0, sizeof(map)); map.m_lblk = start_blk; - map.m_len = F2FS_BYTES_TO_BLK(len); + map.m_len = blk_len; map.m_next_pgofs = &next_pgofs; map.m_seg_type = NO_CHECK_TYPE;

@@ -1970,6 +1969,17 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, flags |= FIEMAP_EXTENT_LAST; }

+ /* + * current extent may cross boundary of inquiry, increase len to + * requery. + */ + if (!compr_cluster && (map.m_flags & F2FS_MAP_MAPPED) && + map.m_lblk + map.m_len - 1 == last_blk && + blk_len != max_len) { + blk_len = max_len; + goto next; + } + compr_appended = false; /* In a case of compressed cluster, append this to the last extent */ if (compr_cluster && ((map.m_flags & F2FS_MAP_DELALLOC) ||