diff options
| author | aliguori <aliguori@c046a42c-6fe2-441c-8c8c-71466251a162> | 2009-03-13 03:12:03 +0000 |
|---|---|---|
| committer | aliguori <aliguori@c046a42c-6fe2-441c-8c8c-71466251a162> | 2009-03-13 03:12:03 +0000 |
| commit | 537a1d4bb02b7c5d21c8f3c853f7c7ae3782bc3f (patch) | |
| tree | 93f68beb4ac7fc625c08cd06a690bf170c0fba0e /block-raw-posix.c | |
| parent | 610626af30fc142e3d420cbce6ac8bdb70377b50 (diff) | |
Fix regression introduced by r6824
The changes introduced by r6824 broke a subtle, and admittedly obscure, aspect
of the block API. While bdrv_{pread,pwrite} return the number of bytes read
or written upon success, bdrv_{read,write} returns a zero upon success.
When using bdrv_pread for bdrv_read, special care must be taken to handle this
case.
This fixes certain guest images (notably linux-0.2 provided on the qemu
website).
Reported-by: malc <av1474@comtv.ru>
Reported-by: Herve Poussineau <hpoussin@reactos.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6828 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'block-raw-posix.c')
| -rw-r--r-- | block-raw-posix.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/block-raw-posix.c b/block-raw-posix.c index 696128b80b..1a1a1781bc 100644 --- a/block-raw-posix.c +++ b/block-raw-posix.c @@ -361,7 +361,12 @@ static int raw_pread(BlockDriverState *bs, int64_t offset, static int raw_read(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, int nb_sectors) { - return raw_pread(bs, sector_num * 512, buf, (uint64_t)nb_sectors * 512); + int ret; + + ret = raw_pread(bs, sector_num * 512, buf, nb_sectors * 512); + if (ret == (nb_sectors * 512)) + ret = 0; + return ret; } /* @@ -445,7 +450,11 @@ static int raw_pwrite(BlockDriverState *bs, int64_t offset, static int raw_write(BlockDriverState *bs, int64_t sector_num, const uint8_t *buf, int nb_sectors) { - return raw_pwrite(bs, sector_num * 512, buf, (uint64_t)nb_sectors * 512); + int ret; + ret = raw_pwrite(bs, sector_num * 512, buf, nb_sectors * 512); + if (ret == (nb_sectors * 512)) + ret = 0; + return ret; } #ifdef CONFIG_AIO |