From b0ad5a455d7e5352d4c86ba945112011dbeadfb8 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Fri, 18 Jun 2010 16:31:14 +0200 Subject: cow: Use bdrv_(p)write_sync for metadata writes Use bdrv_(p)write_sync to ensure metadata integrity in case of a crash. While at it, correct the wrong usage of errno. Signed-off-by: Kevin Wolf --- block/cow.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) (limited to 'block') diff --git a/block/cow.c b/block/cow.c index d146434181..eedcc48772 100644 --- a/block/cow.c +++ b/block/cow.c @@ -97,17 +97,18 @@ static inline int cow_set_bit(BlockDriverState *bs, int64_t bitnum) { uint64_t offset = sizeof(struct cow_header_v2) + bitnum / 8; uint8_t bitmap; + int ret; - if (bdrv_pread(bs->file, offset, &bitmap, sizeof(bitmap)) != - sizeof(bitmap)) { - return -errno; + ret = bdrv_pread(bs->file, offset, &bitmap, sizeof(bitmap)); + if (ret < 0) { + return ret; } bitmap |= (1 << (bitnum % 8)); - if (bdrv_pwrite(bs->file, offset, &bitmap, sizeof(bitmap)) != - sizeof(bitmap)) { - return -errno; + ret = bdrv_pwrite_sync(bs->file, offset, &bitmap, sizeof(bitmap)); + if (ret < 0) { + return ret; } return 0; } @@ -116,10 +117,11 @@ static inline int is_bit_set(BlockDriverState *bs, int64_t bitnum) { uint64_t offset = sizeof(struct cow_header_v2) + bitnum / 8; uint8_t bitmap; + int ret; - if (bdrv_pread(bs->file, offset, &bitmap, sizeof(bitmap)) != - sizeof(bitmap)) { - return -errno; + ret = bdrv_pread(bs->file, offset, &bitmap, sizeof(bitmap)); + if (ret < 0) { + return ret; } return !!(bitmap & (1 << (bitnum % 8))); -- cgit v1.2.3