From d663640c04f2aab810915c556390211d75457704 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 4 Sep 2013 19:00:25 +0200 Subject: [PATCH] block: expect errors from bdrv_co_is_allocated Some bdrv_is_allocated callers do not expect errors, but the fallback in qcow2.c might make other callers trip on assertion failures or infinite loops. Fix the callers to always look for errors. Cc: qemu-stable@nongnu.org Reviewed-by: Eric Blake Signed-off-by: Paolo Bonzini Signed-off-by: Stefan Hajnoczi --- block.c | 7 +++++-- block/cow.c | 6 +++++- block/qcow2.c | 4 +--- block/stream.c | 2 +- qemu-img.c | 16 ++++++++++++++-- qemu-io-cmds.c | 4 ++++ 6 files changed, 30 insertions(+), 9 deletions(-) diff --git a/block.c b/block.c index c6404ebbf8e..5df17de5a48 100644 --- a/block.c +++ b/block.c @@ -1857,8 +1857,11 @@ int bdrv_commit(BlockDriverState *bs) buf = g_malloc(COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE); for (sector = 0; sector < total_sectors; sector += n) { - if (bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n)) { - + ret = bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n); + if (ret < 0) { + goto ro_cleanup; + } + if (ret) { if (bdrv_read(bs, sector, buf, n) != 0) { ret = -EIO; goto ro_cleanup; diff --git a/block/cow.c b/block/cow.c index f4eca10e3f1..7450801cb73 100644 --- a/block/cow.c +++ b/block/cow.c @@ -212,7 +212,11 @@ static int coroutine_fn cow_read(BlockDriverState *bs, int64_t sector_num, int ret, n; while (nb_sectors > 0) { - if (cow_co_is_allocated(bs, sector_num, nb_sectors, &n)) { + ret = cow_co_is_allocated(bs, sector_num, nb_sectors, &n); + if (ret < 0) { + return ret; + } + if (ret) { ret = bdrv_pread(bs->file, s->cow_sectors_offset + sector_num * 512, buf, n * 512); diff --git a/block/qcow2.c b/block/qcow2.c index 4d7bd78b94a..cf03a14ae0e 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -696,13 +696,11 @@ static int coroutine_fn qcow2_co_is_allocated(BlockDriverState *bs, int ret; *pnum = nb_sectors; - /* FIXME We can get errors here, but the bdrv_co_is_allocated interface - * can't pass them on today */ qemu_co_mutex_lock(&s->lock); ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset); qemu_co_mutex_unlock(&s->lock); if (ret < 0) { - *pnum = 0; + return ret; } return (cluster_offset != 0) || (ret == QCOW2_CLUSTER_ZERO); diff --git a/block/stream.c b/block/stream.c index e640bc57e57..078ce4aa6a3 100644 --- a/block/stream.c +++ b/block/stream.c @@ -124,7 +124,7 @@ wait: if (ret == 1) { /* Allocated in the top, no need to copy. */ copy = false; - } else { + } else if (ret >= 0) { /* Copy if allocated in the intermediate images. Limit to the * known-unallocated area [sector_num, sector_num+n). */ ret = bdrv_is_allocated_above(bs->backing_hd, base, diff --git a/qemu-img.c b/qemu-img.c index 744c0d9e4dc..27cc0064b67 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1508,8 +1508,15 @@ static int img_convert(int argc, char **argv) are present in both the output's and input's base images (no need to copy them). */ if (out_baseimg) { - if (!bdrv_is_allocated(bs[bs_i], sector_num - bs_offset, - n, &n1)) { + ret = bdrv_is_allocated(bs[bs_i], sector_num - bs_offset, + n, &n1); + if (ret < 0) { + error_report("error while reading metadata for sector " + "%" PRId64 ": %s", + sector_num - bs_offset, strerror(-ret)); + goto out; + } + if (!ret) { sector_num += n1; continue; } @@ -2099,6 +2106,11 @@ static int img_rebase(int argc, char **argv) /* If the cluster is allocated, we don't need to take action */ ret = bdrv_is_allocated(bs, sector, n, &n); + if (ret < 0) { + error_report("error while reading image metadata: %s", + strerror(-ret)); + goto out; + } if (ret) { continue; } diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c index f91b6c4f029..8565d49336a 100644 --- a/qemu-io-cmds.c +++ b/qemu-io-cmds.c @@ -1830,6 +1830,10 @@ static int alloc_f(BlockDriverState *bs, int argc, char **argv) sector_num = offset >> 9; while (remaining) { ret = bdrv_is_allocated(bs, sector_num, remaining, &num); + if (ret < 0) { + printf("is_allocated failed: %s\n", strerror(-ret)); + return 0; + } sector_num += num; remaining -= num; if (ret) { -- 2.39.5