diff options
| author | Hugh Dickins <hughd@google.com> | 2023-07-23 14:05:54 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-07-27 13:07:03 -0700 |
| commit | fa598952fac059054316dccb2213478ccb81a0d1 (patch) | |
| tree | e1af0830fa7eb13a73c2688784a399704a9380a1 /mm | |
| parent | 253e5df8b8f0145adb090f57c6f4e6efa52d738e (diff) | |
shmem: minor fixes to splice-read implementation
HWPoison: my reading of folio_test_hwpoison() is that it only tests the
head page of a large folio, whereas splice_folio_into_pipe() will splice
as much of the folio as it can: so for safety we should also check the
has_hwpoisoned flag, set if any of the folio's pages are hwpoisoned.
(Perhaps that ugliness can be improved at the mm end later.)
The call to splice_zeropage_into_pipe() risked overrunning past EOF: ask
it for "part" not "len".
Link: https://lkml.kernel.org/r/32c72c9c-72a8-115f-407d-f0148f368@google.com
Fixes: bd194b187115 ("shmem: Implement splice-read")
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/shmem.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 2f2e0e618072..f5af4b943e42 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2796,7 +2796,8 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos, if (*ppos >= i_size_read(inode)) break; - error = shmem_get_folio(inode, *ppos / PAGE_SIZE, &folio, SGP_READ); + error = shmem_get_folio(inode, *ppos / PAGE_SIZE, &folio, + SGP_READ); if (error) { if (error == -EINVAL) error = 0; @@ -2805,7 +2806,9 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos, if (folio) { folio_unlock(folio); - if (folio_test_hwpoison(folio)) { + if (folio_test_hwpoison(folio) || + (folio_test_large(folio) && + folio_test_has_hwpoisoned(folio))) { error = -EIO; break; } @@ -2841,7 +2844,7 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos, folio_put(folio); folio = NULL; } else { - n = splice_zeropage_into_pipe(pipe, *ppos, len); + n = splice_zeropage_into_pipe(pipe, *ppos, part); } if (!n) |