diff options
| -rw-r--r-- | block/qcow2-cluster.c | 41 | ||||
| -rw-r--r-- | block/qcow2.c | 24 | ||||
| -rw-r--r-- | block/qcow2.h | 4 |
3 files changed, 32 insertions, 37 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 550850b264..71ddb0c462 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -496,10 +496,15 @@ static int coroutine_fn do_perform_cow_write(BlockDriverState *bs, /* - * get_cluster_offset + * get_host_offset * - * For a given offset of the virtual disk, find the cluster type and offset in - * the qcow2 file. The offset is stored in *cluster_offset. + * For a given offset of the virtual disk find the equivalent host + * offset in the qcow2 file and store it in *host_offset. Neither + * offset needs to be aligned to a cluster boundary. + * + * If the cluster is unallocated then *host_offset will be 0. + * If the cluster is compressed then *host_offset will contain the + * complete compressed cluster descriptor. * * On entry, *bytes is the maximum number of contiguous bytes starting at * offset that we are interested in. @@ -511,12 +516,12 @@ static int coroutine_fn do_perform_cow_write(BlockDriverState *bs, * Returns the cluster type (QCOW2_CLUSTER_*) on success, -errno in error * cases. */ -int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, - unsigned int *bytes, uint64_t *cluster_offset) +int qcow2_get_host_offset(BlockDriverState *bs, uint64_t offset, + unsigned int *bytes, uint64_t *host_offset) { BDRVQcow2State *s = bs->opaque; unsigned int l2_index; - uint64_t l1_index, l2_offset, *l2_slice; + uint64_t l1_index, l2_offset, *l2_slice, l2_entry; int c; unsigned int offset_in_cluster; uint64_t bytes_available, bytes_needed, nb_clusters; @@ -537,7 +542,7 @@ int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, bytes_needed = bytes_available; } - *cluster_offset = 0; + *host_offset = 0; /* seek to the l2 offset in the l1 table */ @@ -570,7 +575,7 @@ int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, /* find the cluster offset for the given disk offset */ l2_index = offset_to_l2_slice_index(s, offset); - *cluster_offset = be64_to_cpu(l2_slice[l2_index]); + l2_entry = be64_to_cpu(l2_slice[l2_index]); nb_clusters = size_to_clusters(s, bytes_needed); /* bytes_needed <= *bytes + offset_in_cluster, both of which are unsigned @@ -578,7 +583,7 @@ int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, * true */ assert(nb_clusters <= INT_MAX); - type = qcow2_get_cluster_type(bs, *cluster_offset); + type = qcow2_get_cluster_type(bs, l2_entry); if (s->qcow_version < 3 && (type == QCOW2_CLUSTER_ZERO_PLAIN || type == QCOW2_CLUSTER_ZERO_ALLOC)) { qcow2_signal_corruption(bs, true, -1, -1, "Zero cluster entry found" @@ -599,42 +604,42 @@ int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, } /* Compressed clusters can only be processed one by one */ c = 1; - *cluster_offset &= L2E_COMPRESSED_OFFSET_SIZE_MASK; + *host_offset = l2_entry & L2E_COMPRESSED_OFFSET_SIZE_MASK; break; case QCOW2_CLUSTER_ZERO_PLAIN: case QCOW2_CLUSTER_UNALLOCATED: /* how many empty clusters ? */ c = count_contiguous_clusters_unallocated(bs, nb_clusters, &l2_slice[l2_index], type); - *cluster_offset = 0; break; case QCOW2_CLUSTER_ZERO_ALLOC: - case QCOW2_CLUSTER_NORMAL: + case QCOW2_CLUSTER_NORMAL: { + uint64_t host_cluster_offset = l2_entry & L2E_OFFSET_MASK; + *host_offset = host_cluster_offset + offset_in_cluster; /* how many allocated clusters ? */ c = count_contiguous_clusters(bs, nb_clusters, s->cluster_size, &l2_slice[l2_index], QCOW_OFLAG_ZERO); - *cluster_offset &= L2E_OFFSET_MASK; - if (offset_into_cluster(s, *cluster_offset)) { + if (offset_into_cluster(s, host_cluster_offset)) { qcow2_signal_corruption(bs, true, -1, -1, "Cluster allocation offset %#" PRIx64 " unaligned (L2 offset: %#" PRIx64 - ", L2 index: %#x)", *cluster_offset, + ", L2 index: %#x)", host_cluster_offset, l2_offset, l2_index); ret = -EIO; goto fail; } - if (has_data_file(bs) && *cluster_offset != offset - offset_in_cluster) - { + if (has_data_file(bs) && *host_offset != offset) { qcow2_signal_corruption(bs, true, -1, -1, "External data file host cluster offset %#" PRIx64 " does not match guest cluster " "offset: %#" PRIx64 - ", L2 index: %#x)", *cluster_offset, + ", L2 index: %#x)", host_cluster_offset, offset - offset_in_cluster, l2_index); ret = -EIO; goto fail; } break; + } default: abort(); } diff --git a/block/qcow2.c b/block/qcow2.c index 5ab1f45fe2..6738daa247 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2036,7 +2036,7 @@ static int coroutine_fn qcow2_co_block_status(BlockDriverState *bs, BlockDriverState **file) { BDRVQcow2State *s = bs->opaque; - uint64_t cluster_offset; + uint64_t host_offset; unsigned int bytes; int ret, status = 0; @@ -2049,7 +2049,7 @@ static int coroutine_fn qcow2_co_block_status(BlockDriverState *bs, } bytes = MIN(INT_MAX, count); - ret = qcow2_get_cluster_offset(bs, offset, &bytes, &cluster_offset); + ret = qcow2_get_host_offset(bs, offset, &bytes, &host_offset); qemu_co_mutex_unlock(&s->lock); if (ret < 0) { return ret; @@ -2059,7 +2059,7 @@ static int coroutine_fn qcow2_co_block_status(BlockDriverState *bs, if ((ret == QCOW2_CLUSTER_NORMAL || ret == QCOW2_CLUSTER_ZERO_ALLOC) && !s->crypto) { - *map = cluster_offset | offset_into_cluster(s, offset); + *map = host_offset; *file = s->data_file->bs; status |= BDRV_BLOCK_OFFSET_VALID; } @@ -2273,7 +2273,7 @@ static coroutine_fn int qcow2_co_preadv_part(BlockDriverState *bs, BDRVQcow2State *s = bs->opaque; int ret = 0; unsigned int cur_bytes; /* number of bytes in current iteration */ - uint64_t cluster_offset = 0; + uint64_t host_offset = 0; AioTaskPool *aio = NULL; while (bytes != 0 && aio_task_pool_status(aio) == 0) { @@ -2285,7 +2285,7 @@ static coroutine_fn int qcow2_co_preadv_part(BlockDriverState *bs, } qemu_co_mutex_lock(&s->lock); - ret = qcow2_get_cluster_offset(bs, offset, &cur_bytes, &cluster_offset); + ret = qcow2_get_host_offset(bs, offset, &cur_bytes, &host_offset); qemu_co_mutex_unlock(&s->lock); if (ret < 0) { goto out; @@ -2297,15 +2297,6 @@ static coroutine_fn int qcow2_co_preadv_part(BlockDriverState *bs, { qemu_iovec_memset(qiov, qiov_offset, 0, cur_bytes); } else { - /* - * For compressed clusters the variable cluster_offset - * does not actually store the offset but the full - * descriptor. We need to leave it unchanged because - * that's what qcow2_co_preadv_compressed() expects. - */ - uint64_t host_offset = (ret == QCOW2_CLUSTER_COMPRESSED) ? - cluster_offset : - cluster_offset + offset_into_cluster(s, offset); if (!aio && cur_bytes != bytes) { aio = aio_task_pool_new(QCOW2_MAX_WORKERS); } @@ -3853,7 +3844,7 @@ static coroutine_fn int qcow2_co_pwrite_zeroes(BlockDriverState *bs, offset = QEMU_ALIGN_DOWN(offset, s->cluster_size); bytes = s->cluster_size; nr = s->cluster_size; - ret = qcow2_get_cluster_offset(bs, offset, &nr, &off); + ret = qcow2_get_host_offset(bs, offset, &nr, &off); if (ret != QCOW2_CLUSTER_UNALLOCATED && ret != QCOW2_CLUSTER_ZERO_PLAIN && ret != QCOW2_CLUSTER_ZERO_ALLOC) { @@ -3924,7 +3915,7 @@ qcow2_co_copy_range_from(BlockDriverState *bs, cur_bytes = MIN(bytes, INT_MAX); cur_write_flags = write_flags; - ret = qcow2_get_cluster_offset(bs, src_offset, &cur_bytes, ©_offset); + ret = qcow2_get_host_offset(bs, src_offset, &cur_bytes, ©_offset); if (ret < 0) { goto out; } @@ -3956,7 +3947,6 @@ qcow2_co_copy_range_from(BlockDriverState *bs, case QCOW2_CLUSTER_NORMAL: child = s->data_file; - copy_offset += offset_into_cluster(s, src_offset); break; default: diff --git a/block/qcow2.h b/block/qcow2.h index 7ce2c23bdb..06475e0849 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -694,8 +694,8 @@ int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index); int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num, uint8_t *buf, int nb_sectors, bool enc, Error **errp); -int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, - unsigned int *bytes, uint64_t *cluster_offset); +int qcow2_get_host_offset(BlockDriverState *bs, uint64_t offset, + unsigned int *bytes, uint64_t *host_offset); int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, unsigned int *bytes, uint64_t *host_offset, QCowL2Meta **m); |