tmpfs: make lseek(SEEK_DATA/SEK_HOLE) return ENXIO with a negative offset
authorYufen Yu <yuyufen@huawei.com>
Fri, 16 Nov 2018 23:08:39 +0000 (15:08 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sun, 18 Nov 2018 18:15:10 +0000 (10:15 -0800)
commit1a413646931cb14442065cfc17561e50f5b5bb44
tree4de7ceeadbf4261f07510921e23bd83b603d0f64
parent1c23b4108d716cc848b38532063a8aca4f86add8
tmpfs: make lseek(SEEK_DATA/SEK_HOLE) return ENXIO with a negative offset

Other filesystems such as ext4, f2fs and ubifs all return ENXIO when
lseek (SEEK_DATA or SEEK_HOLE) requests a negative offset.

man 2 lseek says

:      EINVAL whence  is  not  valid.   Or: the resulting file offset would be
:             negative, or beyond the end of a seekable device.
:
:      ENXIO  whence is SEEK_DATA or SEEK_HOLE, and the file offset is  beyond
:             the end of the file.

Make tmpfs return ENXIO under these circumstances as well.  After this,
tmpfs also passes xfstests's generic/448.

[akpm@linux-foundation.org: rewrite changelog]
Link: http://lkml.kernel.org/r/1540434176-14349-1-git-send-email-yuyufen@huawei.com
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Hugh Dickins <hughd@google.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/shmem.c