If returned parameters of statx() are: a)STATX_DIOALIGN is set in
stx_mask, b)stx.stx_dio_offset_align is zero, it indicates filesystem
supports DIO, but the file doesn't.
It needs to avoid returning zeroed stx.stx_dio_offset_align value,
instead, we can fallthrough to get alignment size of block device or
page size, otherwise, it may cause potential deadloop, e.g.
generic/465:
align=stx_dio_offset_align(it equals to zero)
page_size=4096
while [ $align -le $page_size ]; do
echo "$AIO_TEST -a $align -d $testfile.$align" >> $seqres.full
$AIO_TEST -a $align -d $testfile.$align 2>&1 | tee -a $seqres.full
align=$((align * 2))
done
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
src/min_dio_alignment.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/src/min_dio_alignment.c b/src/min_dio_alignment.c
index 131f6023..c1d7112d 100644
--- a/src/min_dio_alignment.c
+++ b/src/min_dio_alignment.c
@@ -28,7 +28,7 @@ static int min_dio_alignment(const char *mntpnt, const char *devname)
fd = open(mntpnt, O_TMPFILE | O_RDWR | O_EXCL, 0600);
if (fd >= 0 &&
xfstests_statx(fd, "", AT_EMPTY_PATH, STATX_DIOALIGN, &stx) == 0 &&
- (stx.stx_mask & STATX_DIOALIGN))
+ (stx.stx_mask & STATX_DIOALIGN) && stx.stx_dio_offset_align != 0)
return stx.stx_dio_offset_align;
/*
--
2.40.1
