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

From: Jaegeuk Kim
Date: Fri Apr 07 2023 - 16:59:30 EST


This breaks generic/009?

On 04/05, Chao Yu wrote:
> 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