[PATCH] f2fs: fix to tag FIEMAP_EXTENT_DELALLOC in fiemap() for delay allocated extent

From: Chao Yu
Date: Wed Apr 05 2023 - 12:21:46 EST


xfstest generic/614 fails to run due below reason:

generic/614 1s ... [not run] test requires delayed allocation buffered writes

The root cause is f2fs tags wrong fiemap flag for delay allocated
extent.

Quoted from fiemap.h:
FIEMAP_EXTENT_UNKNOWN 0x00000002 /* Data location unknown. */
FIEMAP_EXTENT_DELALLOC 0x00000004 /* Location still pending.
* Sets EXTENT_UNKNOWN. */
FIEMAP_EXTENT_UNWRITTEN 0x00000800 /* Space allocated, but
* no data (i.e. zero). */

FIEMAP_EXTENT_UNWRITTEN means block address is preallocated, but w/o
been written any data, which status f2fs is not supported now, for all
NEW_ADDR block addresses, it means delay allocated blocks, so let's
tag FIEMAP_EXTENT_DELALLOC instead.

Testcase:
xfs_io -f -c 'pwrite 0 64k' /mnt/f2fs/file;
filefrag -v /mnt/f2fs/file

Output:
- Before
Filesystem type is: f2f52010
Fize of /mnt/f2fs/file is 65536 (16 blocks of 4096 bytes)
ext: logical_offset: physical_offset: length: expected: flags:
0: 0.. 15: 0.. 15: 16: last,unwritten,merged,eof
/mnt/f2fs/file: 1 extent found

After:
Filesystem type is: f2f52010
File size of /mnt/f2fs/file is 65536 (16 blocks of 4096 bytes)
ext: logical_offset: physical_offset: length: expected: flags:
0: 0.. 15: 0.. 0: 0: last,unknown_loc,delalloc,eof
/mnt/f2fs/file: 1 extent found

Fixes: 7f63eb77af7b ("f2fs: report unwritten area in f2fs_fiemap")
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
fs/f2fs/data.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 359de650772e..3afc9764743e 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1995,7 +1995,10 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
}

if (size) {
- flags |= FIEMAP_EXTENT_MERGED;
+ if (flags & FIEMAP_EXTENT_DELALLOC)
+ phys = 0;
+ else
+ flags |= FIEMAP_EXTENT_MERGED;
if (IS_ENCRYPTED(inode))
flags |= FIEMAP_EXTENT_DATA_ENCRYPTED;

@@ -2035,7 +2038,7 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
size += blks_to_bytes(inode, 1);
}
} else if (map.m_flags & F2FS_MAP_DELALLOC) {
- flags = FIEMAP_EXTENT_UNWRITTEN;
+ flags = FIEMAP_EXTENT_DELALLOC;
}

start_blk += bytes_to_blks(inode, size);
--
2.36.1