From 77e023ff79222191e8cc3d377504da8f19926837 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Wed, 27 Feb 2019 10:26:24 +0100 Subject: [PATCH] qcow2: Return 0/-errno in qcow2_alloc_compressed_cluster_offset() qcow2_alloc_compressed_cluster_offset() used to return the cluster offset for success and 0 for error. This doesn't only conflict with 0 as a valid host offset, but also loses the error code. Similar to the change made to qcow2_alloc_cluster_offset() for uncompressed clusters in commit 148da7ea9d6, make the function return 0/-errno and return the allocated cluster offset in a by-reference parameter. Signed-off-by: Kevin Wolf --- block/qcow2-cluster.c | 28 +++++++++++++--------------- block/qcow2.c | 19 ++++++++----------- block/qcow2.h | 7 ++++--- tests/qemu-iotests/220.out | 2 +- 4 files changed, 26 insertions(+), 30 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 1d09f5454e..8c4b4005ff 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -736,19 +736,16 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset, /* * alloc_compressed_cluster_offset * - * For a given offset of the disk image, return cluster offset in - * qcow2 file. - * - * If the offset is not found, allocate a new compressed cluster. - * - * Return the cluster offset if successful, - * Return 0, otherwise. + * For a given offset on the virtual disk, allocate a new compressed cluster + * and put the host offset of the cluster into *host_offset. If a cluster is + * already allocated at the offset, return an error. * + * Return 0 on success and -errno in error cases */ - -uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, - uint64_t offset, - int compressed_size) +int qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, + uint64_t offset, + int compressed_size, + uint64_t *host_offset) { BDRVQcow2State *s = bs->opaque; int l2_index, ret; @@ -758,7 +755,7 @@ uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, ret = get_cluster_table(bs, offset, &l2_slice, &l2_index); if (ret < 0) { - return 0; + return ret; } /* Compression can't overwrite anything. Fail if the cluster was already @@ -766,13 +763,13 @@ uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, cluster_offset = be64_to_cpu(l2_slice[l2_index]); if (cluster_offset & L2E_OFFSET_MASK) { qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); - return 0; + return -EIO; } cluster_offset = qcow2_alloc_bytes(bs, compressed_size); if (cluster_offset < 0) { qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); - return 0; + return cluster_offset; } nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) - @@ -790,7 +787,8 @@ uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, l2_slice[l2_index] = cpu_to_be64(cluster_offset); qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); - return cluster_offset; + *host_offset = cluster_offset & s->cluster_offset_mask; + return 0; } static int perform_cow(BlockDriverState *bs, QCowL2Meta *m) diff --git a/block/qcow2.c b/block/qcow2.c index 59cf706dc2..eaccd1c11a 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3896,17 +3896,16 @@ qcow2_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset, int ret; size_t out_len; uint8_t *buf, *out_buf; - int64_t cluster_offset; + uint64_t cluster_offset; if (bytes == 0) { /* align end of file to a sector boundary to ease reading with sector based I/Os */ - cluster_offset = bdrv_getlength(bs->file->bs); - if (cluster_offset < 0) { - return cluster_offset; + int64_t len = bdrv_getlength(bs->file->bs); + if (len < 0) { + return len; } - return bdrv_co_truncate(bs->file, cluster_offset, PREALLOC_MODE_OFF, - NULL); + return bdrv_co_truncate(bs->file, len, PREALLOC_MODE_OFF, NULL); } if (offset_into_cluster(s, offset)) { @@ -3943,14 +3942,12 @@ qcow2_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset, } qemu_co_mutex_lock(&s->lock); - cluster_offset = - qcow2_alloc_compressed_cluster_offset(bs, offset, out_len); - if (!cluster_offset) { + ret = qcow2_alloc_compressed_cluster_offset(bs, offset, out_len, + &cluster_offset); + if (ret < 0) { qemu_co_mutex_unlock(&s->lock); - ret = -EIO; goto fail; } - cluster_offset &= s->cluster_offset_mask; ret = qcow2_pre_write_overlap_check(bs, 0, cluster_offset, out_len); qemu_co_mutex_unlock(&s->lock); diff --git a/block/qcow2.h b/block/qcow2.h index e3bf322be1..fad6abf602 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -647,9 +647,10 @@ int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, unsigned int *bytes, uint64_t *host_offset, QCowL2Meta **m); -uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, - uint64_t offset, - int compressed_size); +int qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, + uint64_t offset, + int compressed_size, + uint64_t *host_offset); int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m); void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m); diff --git a/tests/qemu-iotests/220.out b/tests/qemu-iotests/220.out index af3021fd88..33b994b8a1 100644 --- a/tests/qemu-iotests/220.out +++ b/tests/qemu-iotests/220.out @@ -38,7 +38,7 @@ wrote 2097152/2097152 bytes at offset 37748736 No errors were found on the image. image size 39845888 == Trying to write compressed cluster == -write failed: Input/output error +write failed: File too large image size 562949957615616 == Writing normal cluster == wrote 2097152/2097152 bytes at offset 0