diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 183177d51804..ee50500a076d 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1640,7 +1640,7 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, for (i = 0; i < l1_size; i++) { uint64_t l2_offset = l1_table[i] & L1E_OFFSET_MASK; bool l2_dirty = false; - int l2_refcount; + uint16_t l2_refcount; if (!l2_offset) { /* unallocated */ @@ -1672,9 +1672,9 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, goto fail; } - l2_refcount = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits); - if (l2_refcount < 0) { - ret = l2_refcount; + ret = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits, + &l2_refcount); + if (ret < 0) { goto fail; } diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 1a85bcd49c71..d8534903c33b 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -87,26 +87,29 @@ static int load_refcount_block(BlockDriverState *bs, } /* - * Returns the refcount of the cluster given by its index. Any non-negative - * return value is the refcount of the cluster, negative values are -errno - * and indicate an error. + * Retrieves the refcount of the cluster given by its index and stores it in + * *refcount. Returns 0 on success and -errno on failure. */ -int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index) +int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index, + uint16_t *refcount) { BDRVQcowState *s = bs->opaque; uint64_t refcount_table_index, block_index; int64_t refcount_block_offset; int ret; uint16_t *refcount_block; - uint16_t refcount; refcount_table_index = cluster_index >> s->refcount_block_bits; - if (refcount_table_index >= s->refcount_table_size) + if (refcount_table_index >= s->refcount_table_size) { + *refcount = 0; return 0; + } refcount_block_offset = s->refcount_table[refcount_table_index] & REFT_OFFSET_MASK; - if (!refcount_block_offset) + if (!refcount_block_offset) { + *refcount = 0; return 0; + } if (offset_into_cluster(s, refcount_block_offset)) { qcow2_signal_corruption(bs, true, -1, -1, "Refblock offset %#" PRIx64 @@ -122,7 +125,7 @@ int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index) } block_index = cluster_index & (s->refcount_block_size - 1); - refcount = be16_to_cpu(refcount_block[block_index]); + *refcount = be16_to_cpu(refcount_block[block_index]); ret = qcow2_cache_put(bs, s->refcount_block_cache, (void**) &refcount_block); @@ -130,7 +133,7 @@ int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index) return ret; } - return refcount; + return 0; } /* @@ -662,16 +665,17 @@ static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size) { BDRVQcowState *s = bs->opaque; uint64_t i, nb_clusters; - int refcount; + uint16_t refcount; + int ret; nb_clusters = size_to_clusters(s, size); retry: for(i = 0; i < nb_clusters; i++) { uint64_t next_cluster_index = s->free_cluster_index++; - refcount = qcow2_get_refcount(bs, next_cluster_index); + ret = qcow2_get_refcount(bs, next_cluster_index, &refcount); - if (refcount < 0) { - return refcount; + if (ret < 0) { + return ret; } else if (refcount != 0) { goto retry; } @@ -721,7 +725,8 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, BDRVQcowState *s = bs->opaque; uint64_t cluster_index; uint64_t i; - int refcount, ret; + uint16_t refcount; + int ret; assert(nb_clusters >= 0); if (nb_clusters == 0) { @@ -732,10 +737,9 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, /* Check how many clusters there are free */ cluster_index = offset >> s->cluster_bits; for(i = 0; i < nb_clusters; i++) { - refcount = qcow2_get_refcount(bs, cluster_index++); - - if (refcount < 0) { - return refcount; + ret = qcow2_get_refcount(bs, cluster_index++, &refcount); + if (ret < 0) { + return ret; } else if (refcount != 0) { break; } @@ -769,9 +773,10 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size) offset = s->free_byte_offset; if (offset) { - int refcount = qcow2_get_refcount(bs, offset >> s->cluster_bits); - if (refcount < 0) { - return refcount; + uint16_t refcount; + ret = qcow2_get_refcount(bs, offset >> s->cluster_bits, &refcount); + if (ret < 0) { + return ret; } if (refcount == s->refcount_max) { @@ -878,7 +883,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2; bool l1_allocated = false; int64_t old_offset, old_l2_offset; - int i, j, l1_modified = 0, nb_csectors, refcount; + int i, j, l1_modified = 0, nb_csectors; + uint16_t refcount; int ret; l2_table = NULL; @@ -983,9 +989,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, } } - refcount = qcow2_get_refcount(bs, cluster_index); - if (refcount < 0) { - ret = refcount; + ret = qcow2_get_refcount(bs, cluster_index, &refcount); + if (ret < 0) { goto fail; } break; @@ -1026,9 +1031,9 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, goto fail; } } - refcount = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits); - if (refcount < 0) { - ret = refcount; + ret = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits, + &refcount); + if (ret < 0) { goto fail; } else if (refcount == 1) { l2_offset |= QCOW_OFLAG_COPIED; @@ -1346,7 +1351,7 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res, BDRVQcowState *s = bs->opaque; uint64_t *l2_table = qemu_blockalign(bs, s->cluster_size); int ret; - int refcount; + uint16_t refcount; int i, j; for (i = 0; i < s->l1_size; i++) { @@ -1358,8 +1363,9 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res, continue; } - refcount = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits); - if (refcount < 0) { + ret = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits, + &refcount); + if (ret < 0) { /* don't print message nor increment check_errors */ continue; } @@ -1400,9 +1406,10 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res, if ((cluster_type == QCOW2_CLUSTER_NORMAL) || ((cluster_type == QCOW2_CLUSTER_ZERO) && (data_offset != 0))) { - refcount = qcow2_get_refcount(bs, - data_offset >> s->cluster_bits); - if (refcount < 0) { + ret = qcow2_get_refcount(bs, + data_offset >> s->cluster_bits, + &refcount); + if (ret < 0) { /* don't print message nor increment check_errors */ continue; } @@ -1634,13 +1641,14 @@ static void compare_refcounts(BlockDriverState *bs, BdrvCheckResult *res, { BDRVQcowState *s = bs->opaque; int64_t i; - int refcount1, refcount2, ret; + uint16_t refcount1, refcount2; + int ret; for (i = 0, *highest_cluster = 0; i < nb_clusters; i++) { - refcount1 = qcow2_get_refcount(bs, i); - if (refcount1 < 0) { + ret = qcow2_get_refcount(bs, i, &refcount1); + if (ret < 0) { fprintf(stderr, "Can't get refcount for cluster %" PRId64 ": %s\n", - i, strerror(-refcount1)); + i, strerror(-ret)); res->check_errors++; continue; } @@ -1670,7 +1678,7 @@ static void compare_refcounts(BlockDriverState *bs, BdrvCheckResult *res, if (num_fixed) { ret = update_refcount(bs, i << s->cluster_bits, 1, - refcount2 - refcount1, + (int)refcount2 - (int)refcount1, QCOW2_DISCARD_ALWAYS); if (ret >= 0) { (*num_fixed)++; diff --git a/block/qcow2.h b/block/qcow2.h index 55138c9d9203..a33431f05a91 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -478,7 +478,8 @@ void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset, int qcow2_refcount_init(BlockDriverState *bs); void qcow2_refcount_close(BlockDriverState *bs); -int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index); +int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index, + uint16_t *refcount); int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index, int addend, enum qcow2_discard_type type);