diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 1a67b2d928..9acc6ce4ae 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1719,6 +1719,10 @@ out: * clusters (or subclusters) if necessary. The result can span a * combination of allocated and previously unallocated clusters. * + * Note that offset may not be cluster aligned. In this case, the returned + * *host_offset points to exact byte referenced by offset and therefore + * isn't cluster aligned as well. + * * On return, @host_offset is set to the beginning of the requested * area. This area is guaranteed to be contiguous on the qcow2 file * but it can be smaller than initially requested. In this case @bytes @@ -1736,9 +1740,9 @@ out: * * Return 0 on success and -errno in error cases */ -int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, - unsigned int *bytes, uint64_t *host_offset, - QCowL2Meta **m) +int qcow2_alloc_host_offset(BlockDriverState *bs, uint64_t offset, + unsigned int *bytes, uint64_t *host_offset, + QCowL2Meta **m) { BDRVQcow2State *s = bs->opaque; uint64_t start, remaining; @@ -1759,7 +1763,7 @@ again: while (true) { if (*host_offset == INV_OFFSET && cluster_offset != INV_OFFSET) { - *host_offset = start_of_cluster(s, cluster_offset); + *host_offset = cluster_offset; } assert(remaining >= cur_bytes); @@ -1842,6 +1846,8 @@ again: *bytes -= remaining; assert(*bytes > 0); assert(*host_offset != INV_OFFSET); + assert(offset_into_cluster(s, *host_offset) == + offset_into_cluster(s, offset)); return 0; } diff --git a/block/qcow2.c b/block/qcow2.c index 1cb5daf39a..b05512718c 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2559,7 +2559,7 @@ static coroutine_fn int qcow2_co_pwritev_part( int offset_in_cluster; int ret; unsigned int cur_bytes; /* number of sectors in current iteration */ - uint64_t cluster_offset; + uint64_t host_offset; QCowL2Meta *l2meta = NULL; AioTaskPool *aio = NULL; @@ -2580,16 +2580,13 @@ static coroutine_fn int qcow2_co_pwritev_part( qemu_co_mutex_lock(&s->lock); - ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes, - &cluster_offset, &l2meta); + ret = qcow2_alloc_host_offset(bs, offset, &cur_bytes, + &host_offset, &l2meta); if (ret < 0) { goto out_locked; } - assert(offset_into_cluster(s, cluster_offset) == 0); - - ret = qcow2_pre_write_overlap_check(bs, 0, - cluster_offset + offset_in_cluster, + ret = qcow2_pre_write_overlap_check(bs, 0, host_offset, cur_bytes, true); if (ret < 0) { goto out_locked; @@ -2601,7 +2598,7 @@ static coroutine_fn int qcow2_co_pwritev_part( aio = aio_task_pool_new(QCOW2_MAX_WORKERS); } ret = qcow2_add_task(bs, aio, qcow2_co_pwritev_task_entry, 0, - cluster_offset + offset_in_cluster, offset, + host_offset, offset, cur_bytes, qiov, qiov_offset, l2meta); l2meta = NULL; /* l2meta is consumed by qcow2_co_pwritev_task() */ if (ret < 0) { @@ -3129,13 +3126,12 @@ static int coroutine_fn preallocate_co(BlockDriverState *bs, uint64_t offset, while (bytes) { cur_bytes = MIN(bytes, QEMU_ALIGN_DOWN(INT_MAX, s->cluster_size)); - ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes, - &host_offset, &meta); + ret = qcow2_alloc_host_offset(bs, offset, &cur_bytes, + &host_offset, &meta); if (ret < 0) { error_setg_errno(errp, -ret, "Allocating clusters failed"); goto out; } - host_offset += offset_into_cluster(s, offset); for (m = meta; m != NULL; m = m->next) { m->prealloc = true; @@ -4043,10 +4039,9 @@ qcow2_co_copy_range_to(BlockDriverState *bs, BdrvRequestFlags write_flags) { BDRVQcow2State *s = bs->opaque; - int offset_in_cluster; int ret; unsigned int cur_bytes; /* number of sectors in current iteration */ - uint64_t cluster_offset; + uint64_t host_offset; QCowL2Meta *l2meta = NULL; assert(!bs->encrypted); @@ -4057,31 +4052,26 @@ qcow2_co_copy_range_to(BlockDriverState *bs, l2meta = NULL; - offset_in_cluster = offset_into_cluster(s, dst_offset); cur_bytes = MIN(bytes, INT_MAX); /* TODO: * If src->bs == dst->bs, we could simply copy by incrementing * the refcnt, without copying user data. * Or if src->bs == dst->bs->backing->bs, we could copy by discarding. */ - ret = qcow2_alloc_cluster_offset(bs, dst_offset, &cur_bytes, - &cluster_offset, &l2meta); + ret = qcow2_alloc_host_offset(bs, dst_offset, &cur_bytes, + &host_offset, &l2meta); if (ret < 0) { goto fail; } - assert(offset_into_cluster(s, cluster_offset) == 0); - - ret = qcow2_pre_write_overlap_check(bs, 0, - cluster_offset + offset_in_cluster, cur_bytes, true); + ret = qcow2_pre_write_overlap_check(bs, 0, host_offset, cur_bytes, + true); if (ret < 0) { goto fail; } qemu_co_mutex_unlock(&s->lock); - ret = bdrv_co_copy_range_to(src, src_offset, - s->data_file, - cluster_offset + offset_in_cluster, + ret = bdrv_co_copy_range_to(src, src_offset, s->data_file, host_offset, cur_bytes, read_flags, write_flags); qemu_co_mutex_lock(&s->lock); if (ret < 0) { diff --git a/block/qcow2.h b/block/qcow2.h index b73a4cf1f8..b71e444fca 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -901,9 +901,9 @@ int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num, int qcow2_get_host_offset(BlockDriverState *bs, uint64_t offset, unsigned int *bytes, uint64_t *host_offset, QCow2SubclusterType *subcluster_type); -int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, - unsigned int *bytes, uint64_t *host_offset, - QCowL2Meta **m); +int qcow2_alloc_host_offset(BlockDriverState *bs, uint64_t offset, + unsigned int *bytes, uint64_t *host_offset, + QCowL2Meta **m); int qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, uint64_t offset, int compressed_size,