diff options
Diffstat (limited to 'block/qcow2-refcount.c')
| -rw-r--r-- | block/qcow2-refcount.c | 545 |
1 files changed, 373 insertions, 172 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 9b80ca79ea..dc8d186a82 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -29,8 +29,52 @@ static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size); static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, - int64_t offset, int64_t length, - int addend, enum qcow2_discard_type type); + int64_t offset, int64_t length, uint64_t addend, + bool decrease, enum qcow2_discard_type type); + +static uint64_t get_refcount_ro0(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro1(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro2(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro3(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro4(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro5(const void *refcount_array, uint64_t index); +static uint64_t get_refcount_ro6(const void *refcount_array, uint64_t index); + +static void set_refcount_ro0(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro1(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro2(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro3(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro4(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro5(void *refcount_array, uint64_t index, + uint64_t value); +static void set_refcount_ro6(void *refcount_array, uint64_t index, + uint64_t value); + + +static Qcow2GetRefcountFunc *const get_refcount_funcs[] = { + &get_refcount_ro0, + &get_refcount_ro1, + &get_refcount_ro2, + &get_refcount_ro3, + &get_refcount_ro4, + &get_refcount_ro5, + &get_refcount_ro6 +}; + +static Qcow2SetRefcountFunc *const set_refcount_funcs[] = { + &set_refcount_ro0, + &set_refcount_ro1, + &set_refcount_ro2, + &set_refcount_ro3, + &set_refcount_ro4, + &set_refcount_ro5, + &set_refcount_ro6 +}; /*********************************************************/ @@ -42,6 +86,11 @@ int qcow2_refcount_init(BlockDriverState *bs) unsigned int refcount_table_size2, i; int ret; + assert(s->refcount_order >= 0 && s->refcount_order <= 6); + + s->get_refcount = get_refcount_funcs[s->refcount_order]; + s->set_refcount = set_refcount_funcs[s->refcount_order]; + assert(s->refcount_table_size <= INT_MAX / sizeof(uint64_t)); refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t); s->refcount_table = g_try_malloc(refcount_table_size2); @@ -72,6 +121,95 @@ void qcow2_refcount_close(BlockDriverState *bs) } +static uint64_t get_refcount_ro0(const void *refcount_array, uint64_t index) +{ + return (((const uint8_t *)refcount_array)[index / 8] >> (index % 8)) & 0x1; +} + +static void set_refcount_ro0(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 1)); + ((uint8_t *)refcount_array)[index / 8] &= ~(0x1 << (index % 8)); + ((uint8_t *)refcount_array)[index / 8] |= value << (index % 8); +} + +static uint64_t get_refcount_ro1(const void *refcount_array, uint64_t index) +{ + return (((const uint8_t *)refcount_array)[index / 4] >> (2 * (index % 4))) + & 0x3; +} + +static void set_refcount_ro1(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 2)); + ((uint8_t *)refcount_array)[index / 4] &= ~(0x3 << (2 * (index % 4))); + ((uint8_t *)refcount_array)[index / 4] |= value << (2 * (index % 4)); +} + +static uint64_t get_refcount_ro2(const void *refcount_array, uint64_t index) +{ + return (((const uint8_t *)refcount_array)[index / 2] >> (4 * (index % 2))) + & 0xf; +} + +static void set_refcount_ro2(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 4)); + ((uint8_t *)refcount_array)[index / 2] &= ~(0xf << (4 * (index % 2))); + ((uint8_t *)refcount_array)[index / 2] |= value << (4 * (index % 2)); +} + +static uint64_t get_refcount_ro3(const void *refcount_array, uint64_t index) +{ + return ((const uint8_t *)refcount_array)[index]; +} + +static void set_refcount_ro3(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 8)); + ((uint8_t *)refcount_array)[index] = value; +} + +static uint64_t get_refcount_ro4(const void *refcount_array, uint64_t index) +{ + return be16_to_cpu(((const uint16_t *)refcount_array)[index]); +} + +static void set_refcount_ro4(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 16)); + ((uint16_t *)refcount_array)[index] = cpu_to_be16(value); +} + +static uint64_t get_refcount_ro5(const void *refcount_array, uint64_t index) +{ + return be32_to_cpu(((const uint32_t *)refcount_array)[index]); +} + +static void set_refcount_ro5(void *refcount_array, uint64_t index, + uint64_t value) +{ + assert(!(value >> 32)); + ((uint32_t *)refcount_array)[index] = cpu_to_be32(value); +} + +static uint64_t get_refcount_ro6(const void *refcount_array, uint64_t index) +{ + return be64_to_cpu(((const uint64_t *)refcount_array)[index]); +} + +static void set_refcount_ro6(void *refcount_array, uint64_t index, + uint64_t value) +{ + ((uint64_t *)refcount_array)[index] = cpu_to_be64(value); +} + + static int load_refcount_block(BlockDriverState *bs, int64_t refcount_block_offset, void **refcount_block) @@ -87,26 +225,29 @@ 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, + uint64_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; + void *refcount_block; 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 @@ -116,21 +257,20 @@ int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index) } ret = qcow2_cache_get(bs, s->refcount_block_cache, refcount_block_offset, - (void**) &refcount_block); + &refcount_block); if (ret < 0) { return ret; } block_index = cluster_index & (s->refcount_block_size - 1); - refcount = be16_to_cpu(refcount_block[block_index]); + *refcount = s->get_refcount(refcount_block, block_index); - ret = qcow2_cache_put(bs, s->refcount_block_cache, - (void**) &refcount_block); + ret = qcow2_cache_put(bs, s->refcount_block_cache, &refcount_block); if (ret < 0) { return ret; } - return refcount; + return 0; } /* @@ -169,7 +309,7 @@ static int in_same_refcount_block(BDRVQcowState *s, uint64_t offset_a, * Returns 0 on success or -errno in error case */ static int alloc_refcount_block(BlockDriverState *bs, - int64_t cluster_index, uint16_t **refcount_block) + int64_t cluster_index, void **refcount_block) { BDRVQcowState *s = bs->opaque; unsigned int refcount_table_index; @@ -196,7 +336,7 @@ static int alloc_refcount_block(BlockDriverState *bs, } return load_refcount_block(bs, refcount_block_offset, - (void**) refcount_block); + refcount_block); } } @@ -246,7 +386,7 @@ static int alloc_refcount_block(BlockDriverState *bs, if (in_same_refcount_block(s, new_block, cluster_index << s->cluster_bits)) { /* Zero the new refcount block before updating it */ ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block, - (void**) refcount_block); + refcount_block); if (ret < 0) { goto fail_block; } @@ -256,11 +396,11 @@ static int alloc_refcount_block(BlockDriverState *bs, /* The block describes itself, need to update the cache */ int block_index = (new_block >> s->cluster_bits) & (s->refcount_block_size - 1); - (*refcount_block)[block_index] = cpu_to_be16(1); + s->set_refcount(*refcount_block, block_index, 1); } else { /* Described somewhere else. This can recurse at most twice before we * arrive at a block that describes itself. */ - ret = update_refcount(bs, new_block, s->cluster_size, 1, + ret = update_refcount(bs, new_block, s->cluster_size, 1, false, QCOW2_DISCARD_NEVER); if (ret < 0) { goto fail_block; @@ -274,7 +414,7 @@ static int alloc_refcount_block(BlockDriverState *bs, /* Initialize the new refcount block only after updating its refcount, * update_refcount uses the refcount cache itself */ ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block, - (void**) refcount_block); + refcount_block); if (ret < 0) { goto fail_block; } @@ -308,7 +448,7 @@ static int alloc_refcount_block(BlockDriverState *bs, return -EAGAIN; } - ret = qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block); + ret = qcow2_cache_put(bs, s->refcount_block_cache, refcount_block); if (ret < 0) { goto fail_block; } @@ -362,7 +502,7 @@ static int alloc_refcount_block(BlockDriverState *bs, s->cluster_size; uint64_t table_offset = meta_offset + blocks_clusters * s->cluster_size; uint64_t *new_table = g_try_new0(uint64_t, table_size); - uint16_t *new_blocks = g_try_malloc0(blocks_clusters * s->cluster_size); + void *new_blocks = g_try_malloc0(blocks_clusters * s->cluster_size); assert(table_size > 0 && blocks_clusters > 0); if (new_table == NULL || new_blocks == NULL) { @@ -384,7 +524,7 @@ static int alloc_refcount_block(BlockDriverState *bs, uint64_t table_clusters = size_to_clusters(s, table_size * sizeof(uint64_t)); int block = 0; for (i = 0; i < table_clusters + blocks_clusters; i++) { - new_blocks[block++] = cpu_to_be16(1); + s->set_refcount(new_blocks, block++, 1); } /* Write refcount blocks to disk */ @@ -437,7 +577,7 @@ static int alloc_refcount_block(BlockDriverState *bs, qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t), QCOW2_DISCARD_OTHER); - ret = load_refcount_block(bs, new_block, (void**) refcount_block); + ret = load_refcount_block(bs, new_block, refcount_block); if (ret < 0) { return ret; } @@ -452,7 +592,7 @@ fail_table: g_free(new_table); fail_block: if (*refcount_block != NULL) { - qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block); + qcow2_cache_put(bs, s->refcount_block_cache, refcount_block); } return ret; } @@ -527,18 +667,25 @@ found: } /* XXX: cache several refcount block clusters ? */ +/* @addend is the absolute value of the addend; if @decrease is set, @addend + * will be subtracted from the current refcount, otherwise it will be added */ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, - int64_t offset, int64_t length, int addend, enum qcow2_discard_type type) + int64_t offset, + int64_t length, + uint64_t addend, + bool decrease, + enum qcow2_discard_type type) { BDRVQcowState *s = bs->opaque; int64_t start, last, cluster_offset; - uint16_t *refcount_block = NULL; + void *refcount_block = NULL; int64_t old_table_index = -1; int ret; #ifdef DEBUG_ALLOC2 - fprintf(stderr, "update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n", - offset, length, addend); + fprintf(stderr, "update_refcount: offset=%" PRId64 " size=%" PRId64 + " addend=%s%" PRIu64 "\n", offset, length, decrease ? "-" : "", + addend); #endif if (length < 0) { return -EINVAL; @@ -546,7 +693,7 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, return 0; } - if (addend < 0) { + if (decrease) { qcow2_cache_set_dependency(bs, s->refcount_block_cache, s->l2_table_cache); } @@ -556,7 +703,8 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, for(cluster_offset = start; cluster_offset <= last; cluster_offset += s->cluster_size) { - int block_index, refcount; + int block_index; + uint64_t refcount; int64_t cluster_index = cluster_offset >> s->cluster_bits; int64_t table_index = cluster_index >> s->refcount_block_bits; @@ -564,7 +712,7 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, if (table_index != old_table_index) { if (refcount_block) { ret = qcow2_cache_put(bs, s->refcount_block_cache, - (void**) &refcount_block); + &refcount_block); if (ret < 0) { goto fail; } @@ -582,16 +730,23 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, /* we can update the count and save it */ block_index = cluster_index & (s->refcount_block_size - 1); - refcount = be16_to_cpu(refcount_block[block_index]); - refcount += addend; - if (refcount < 0 || refcount > 0xffff) { + refcount = s->get_refcount(refcount_block, block_index); + if (decrease ? (refcount - addend > refcount) + : (refcount + addend < refcount || + refcount + addend > s->refcount_max)) + { ret = -EINVAL; goto fail; } + if (decrease) { + refcount -= addend; + } else { + refcount += addend; + } if (refcount == 0 && cluster_index < s->free_cluster_index) { s->free_cluster_index = cluster_index; } - refcount_block[block_index] = cpu_to_be16(refcount); + s->set_refcount(refcount_block, block_index, refcount); if (refcount == 0 && s->discard_passthrough[type]) { update_refcount_discard(bs, cluster_offset, s->cluster_size); @@ -607,8 +762,7 @@ fail: /* Write last changed block to disk */ if (refcount_block) { int wret; - wret = qcow2_cache_put(bs, s->refcount_block_cache, - (void**) &refcount_block); + wret = qcow2_cache_put(bs, s->refcount_block_cache, &refcount_block); if (wret < 0) { return ret < 0 ? ret : wret; } @@ -620,8 +774,8 @@ fail: */ if (ret < 0) { int dummy; - dummy = update_refcount(bs, offset, cluster_offset - offset, -addend, - QCOW2_DISCARD_NEVER); + dummy = update_refcount(bs, offset, cluster_offset - offset, addend, + !decrease, QCOW2_DISCARD_NEVER); (void)dummy; } @@ -631,24 +785,26 @@ fail: /* * Increases or decreases the refcount of a given cluster. * - * If the return value is non-negative, it is the new refcount of the cluster. - * If it is negative, it is -errno and indicates an error. + * @addend is the absolute value of the addend; if @decrease is set, @addend + * will be subtracted from the current refcount, otherwise it will be added. + * + * On success 0 is returned; on failure -errno is returned. */ int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index, - int addend, + uint64_t addend, bool decrease, enum qcow2_discard_type type) { BDRVQcowState *s = bs->opaque; int ret; ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend, - type); + decrease, type); if (ret < 0) { return ret; } - return qcow2_get_refcount(bs, cluster_index); + return 0; } @@ -662,17 +818,17 @@ int qcow2_update_cluster_refcount(BlockDriverState *bs, static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size) { BDRVQcowState *s = bs->opaque; - uint64_t i, nb_clusters; - int refcount; + uint64_t i, nb_clusters, 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; } @@ -706,7 +862,7 @@ int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size) return offset; } - ret = update_refcount(bs, offset, size, 1, QCOW2_DISCARD_NEVER); + ret = update_refcount(bs, offset, size, 1, false, QCOW2_DISCARD_NEVER); } while (ret == -EAGAIN); if (ret < 0) { @@ -720,9 +876,9 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, int nb_clusters) { BDRVQcowState *s = bs->opaque; - uint64_t cluster_index; + uint64_t cluster_index, refcount; uint64_t i; - int refcount, ret; + int ret; assert(nb_clusters >= 0); if (nb_clusters == 0) { @@ -733,17 +889,16 @@ 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; } } /* And then allocate them */ - ret = update_refcount(bs, offset, i << s->cluster_bits, 1, + ret = update_refcount(bs, offset, i << s->cluster_bits, 1, false, QCOW2_DISCARD_NEVER); } while (ret == -EAGAIN); @@ -770,12 +925,13 @@ 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; + uint64_t refcount; + ret = qcow2_get_refcount(bs, offset >> s->cluster_bits, &refcount); + if (ret < 0) { + return ret; } - if (refcount == 0xffff) { + if (refcount == s->refcount_max) { offset = 0; } } @@ -793,7 +949,7 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size) } assert(offset); - ret = update_refcount(bs, offset, size, 1, QCOW2_DISCARD_NEVER); + ret = update_refcount(bs, offset, size, 1, false, QCOW2_DISCARD_NEVER); if (ret < 0) { return ret; } @@ -817,7 +973,7 @@ void qcow2_free_clusters(BlockDriverState *bs, int ret; BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE); - ret = update_refcount(bs, offset, size, -1, type); + ret = update_refcount(bs, offset, size, 1, true, type); if (ret < 0) { fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret)); /* TODO Remember the clusters to free them later and avoid leaking */ @@ -876,12 +1032,14 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, int64_t l1_table_offset, int l1_size, int addend) { BDRVQcowState *s = bs->opaque; - uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2; + uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, refcount; 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; int ret; + assert(addend >= -1 && addend <= 1); + l2_table = NULL; l1_table = NULL; l1_size2 = l1_size * sizeof(uint64_t); @@ -946,7 +1104,7 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, if (addend != 0) { ret = update_refcount(bs, (offset & s->cluster_offset_mask) & ~511, - nb_csectors * 512, addend, + nb_csectors * 512, abs(addend), addend < 0, QCOW2_DISCARD_SNAPSHOT); if (ret < 0) { goto fail; @@ -976,15 +1134,16 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, break; } if (addend != 0) { - refcount = qcow2_update_cluster_refcount(bs, - cluster_index, addend, + ret = qcow2_update_cluster_refcount(bs, + cluster_index, abs(addend), addend < 0, QCOW2_DISCARD_SNAPSHOT); - } else { - refcount = qcow2_get_refcount(bs, cluster_index); + if (ret < 0) { + goto fail; + } } - if (refcount < 0) { - ret = refcount; + ret = qcow2_get_refcount(bs, cluster_index, &refcount); + if (ret < 0) { goto fail; } break; @@ -1017,13 +1176,17 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, if (addend != 0) { - refcount = qcow2_update_cluster_refcount(bs, l2_offset >> - s->cluster_bits, addend, QCOW2_DISCARD_SNAPSHOT); - } else { - refcount = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits); + ret = qcow2_update_cluster_refcount(bs, l2_offset >> + s->cluster_bits, + abs(addend), addend < 0, + QCOW2_DISCARD_SNAPSHOT); + if (ret < 0) { + goto fail; + } } - 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; @@ -1068,6 +1231,63 @@ fail: /* refcount checking functions */ +static size_t refcount_array_byte_size(BDRVQcowState *s, uint64_t entries) +{ + /* This assertion holds because there is no way we can address more than + * 2^(64 - 9) clusters at once (with cluster size 512 = 2^9, and because + * offsets have to be representable in bytes); due to every cluster + * corresponding to one refcount entry, we are well below that limit */ + assert(entries < (UINT64_C(1) << (64 - 9))); + + /* Thanks to the assertion this will not overflow, because + * s->refcount_order < 7. + * (note: x << s->refcount_order == x * s->refcount_bits) */ + return DIV_ROUND_UP(entries << s->refcount_order, 8); +} + +/** + * Reallocates *array so that it can hold new_size entries. *size must contain + * the current number of entries in *array. If the reallocation fails, *array + * and *size will not be modified and -errno will be returned. If the + * reallocation is successful, *array will be set to the new buffer, *size + * will be set to new_size and 0 will be returned. The size of the reallocated + * refcount array buffer will be aligned to a cluster boundary, and the newly + * allocated area will be zeroed. + */ +static int realloc_refcount_array(BDRVQcowState *s, void **array, + int64_t *size, int64_t new_size) +{ + size_t old_byte_size, new_byte_size; + void *new_ptr; + + /* Round to clusters so the array can be directly written to disk */ + old_byte_size = size_to_clusters(s, refcount_array_byte_size(s, *size)) + * s->cluster_size; + new_byte_size = size_to_clusters(s, refcount_array_byte_size(s, new_size)) + * s->cluster_size; + + if (new_byte_size == old_byte_size) { + *size = new_size; + return 0; + } + + assert(new_byte_size > 0); + + new_ptr = g_try_realloc(*array, new_byte_size); + if (!new_ptr) { + return -ENOMEM; + } + + if (new_byte_size > old_byte_size) { + memset((void *)((uintptr_t)new_ptr + old_byte_size), 0, + new_byte_size - old_byte_size); + } + + *array = new_ptr; + *size = new_size; + + return 0; +} /* * Increases the refcount for a range of clusters in a given refcount table. @@ -1078,12 +1298,13 @@ fail: */ static int inc_refcounts(BlockDriverState *bs, BdrvCheckResult *res, - uint16_t **refcount_table, + void **refcount_table, int64_t *refcount_table_size, int64_t offset, int64_t size) { BDRVQcowState *s = bs->opaque; - uint64_t start, last, cluster_offset, k; + uint64_t start, last, cluster_offset, k, refcount; + int ret; if (size <= 0) { return 0; @@ -1095,30 +1316,22 @@ static int inc_refcounts(BlockDriverState *bs, cluster_offset += s->cluster_size) { k = cluster_offset >> s->cluster_bits; if (k >= *refcount_table_size) { - int64_t old_refcount_table_size = *refcount_table_size; - uint16_t *new_refcount_table; - - *refcount_table_size = k + 1; - new_refcount_table = g_try_realloc(*refcount_table, - *refcount_table_size * - sizeof(**refcount_table)); - if (!new_refcount_table) { - *refcount_table_size = old_refcount_table_size; + ret = realloc_refcount_array(s, refcount_table, + refcount_table_size, k + 1); + if (ret < 0) { res->check_errors++; - return -ENOMEM; + return ret; } - *refcount_table = new_refcount_table; - - memset(*refcount_table + old_refcount_table_size, 0, - (*refcount_table_size - old_refcount_table_size) * - sizeof(**refcount_table)); } - if (++(*refcount_table)[k] == 0) { + refcount = s->get_refcount(*refcount_table, k); + if (refcount == s->refcount_max) { fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64 "\n", cluster_offset); res->corruptions++; + continue; } + s->set_refcount(*refcount_table, k, refcount + 1); } return 0; @@ -1138,8 +1351,9 @@ enum { * error occurred. */ static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res, - uint16_t **refcount_table, int64_t *refcount_table_size, int64_t l2_offset, - int flags) + void **refcount_table, + int64_t *refcount_table_size, int64_t l2_offset, + int flags) { BDRVQcowState *s = bs->opaque; uint64_t *l2_table, l2_entry; @@ -1256,7 +1470,7 @@ fail: */ static int check_refcounts_l1(BlockDriverState *bs, BdrvCheckResult *res, - uint16_t **refcount_table, + void **refcount_table, int64_t *refcount_table_size, int64_t l1_table_offset, int l1_size, int flags) @@ -1341,7 +1555,7 @@ 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; + uint64_t refcount; int i, j; for (i = 0; i < s->l1_size; i++) { @@ -1353,14 +1567,15 @@ 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; } if ((refcount == 1) != ((l1_entry & QCOW_OFLAG_COPIED) != 0)) { fprintf(stderr, "%s OFLAG_COPIED L2 cluster: l1_index=%d " - "l1_entry=%" PRIx64 " refcount=%d\n", + "l1_entry=%" PRIx64 " refcount=%" PRIu64 "\n", fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR", i, l1_entry, refcount); @@ -1395,15 +1610,16 @@ 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; } if ((refcount == 1) != ((l2_entry & QCOW_OFLAG_COPIED) != 0)) { fprintf(stderr, "%s OFLAG_COPIED data cluster: " - "l2_entry=%" PRIx64 " refcount=%d\n", + "l2_entry=%" PRIx64 " refcount=%" PRIu64 "\n", fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR", l2_entry, refcount); @@ -1453,7 +1669,7 @@ fail: */ static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix, bool *rebuild, - uint16_t **refcount_table, int64_t *nb_clusters) + void **refcount_table, int64_t *nb_clusters) { BDRVQcowState *s = bs->opaque; int64_t i, size; @@ -1478,8 +1694,7 @@ static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res, fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR", i); if (fix & BDRV_FIX_ERRORS) { - int64_t old_nb_clusters = *nb_clusters; - uint16_t *new_refcount_table; + int64_t new_nb_clusters; if (offset > INT64_MAX - s->cluster_size) { ret = -EINVAL; @@ -1496,22 +1711,15 @@ static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res, goto resize_fail; } - *nb_clusters = size_to_clusters(s, size); - assert(*nb_clusters >= old_nb_clusters); + new_nb_clusters = size_to_clusters(s, size); + assert(new_nb_clusters >= *nb_clusters); - new_refcount_table = g_try_realloc(*refcount_table, - *nb_clusters * - sizeof(**refcount_table)); - if (!new_refcount_table) { - *nb_clusters = old_nb_clusters; + ret = realloc_refcount_array(s, refcount_table, + nb_clusters, new_nb_clusters); + if (ret < 0) { res->check_errors++; - return -ENOMEM; + return ret; } - *refcount_table = new_refcount_table; - - memset(*refcount_table + old_nb_clusters, 0, - (*nb_clusters - old_nb_clusters) * - sizeof(**refcount_table)); if (cluster >= *nb_clusters) { ret = -EINVAL; @@ -1546,9 +1754,10 @@ resize_fail: if (ret < 0) { return ret; } - if ((*refcount_table)[cluster] != 1) { + if (s->get_refcount(*refcount_table, cluster) != 1) { fprintf(stderr, "ERROR refcount block %" PRId64 - " refcount=%d\n", i, (*refcount_table)[cluster]); + " refcount=%" PRIu64 "\n", i, + s->get_refcount(*refcount_table, cluster)); res->corruptions++; *rebuild = true; } @@ -1563,7 +1772,7 @@ resize_fail: */ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix, bool *rebuild, - uint16_t **refcount_table, int64_t *nb_clusters) + void **refcount_table, int64_t *nb_clusters) { BDRVQcowState *s = bs->opaque; int64_t i; @@ -1571,10 +1780,12 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res, int ret; if (!*refcount_table) { - *refcount_table = g_try_new0(uint16_t, *nb_clusters); - if (*nb_clusters && *refcount_table == NULL) { + int64_t old_size = 0; + ret = realloc_refcount_array(s, refcount_table, + &old_size, *nb_clusters); + if (ret < 0) { res->check_errors++; - return -ENOMEM; + return ret; } } @@ -1625,22 +1836,23 @@ static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res, static void compare_refcounts(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix, bool *rebuild, int64_t *highest_cluster, - uint16_t *refcount_table, int64_t nb_clusters) + void *refcount_table, int64_t nb_clusters) { BDRVQcowState *s = bs->opaque; int64_t i; - int refcount1, refcount2, ret; + uint64_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; } - refcount2 = refcount_table[i]; + refcount2 = s->get_refcount(refcount_table, i); if (refcount1 > 0 || refcount2 > 0) { *highest_cluster = i; @@ -1657,7 +1869,8 @@ static void compare_refcounts(BlockDriverState *bs, BdrvCheckResult *res, num_fixed = &res->corruptions_fixed; } - fprintf(stderr, "%s cluster %" PRId64 " refcount=%d reference=%d\n", + fprintf(stderr, "%s cluster %" PRId64 " refcount=%" PRIu64 + " reference=%" PRIu64 "\n", num_fixed != NULL ? "Repairing" : refcount1 < refcount2 ? "ERROR" : "Leaked", @@ -1665,7 +1878,8 @@ static void compare_refcounts(BlockDriverState *bs, BdrvCheckResult *res, if (num_fixed) { ret = update_refcount(bs, i << s->cluster_bits, 1, - refcount2 - refcount1, + refcount_diff(refcount1, refcount2), + refcount1 > refcount2, QCOW2_DISCARD_ALWAYS); if (ret >= 0) { (*num_fixed)++; @@ -1697,7 +1911,7 @@ static void compare_refcounts(BlockDriverState *bs, BdrvCheckResult *res, */ static int64_t alloc_clusters_imrt(BlockDriverState *bs, int cluster_count, - uint16_t **refcount_table, + void **refcount_table, int64_t *imrt_nb_clusters, int64_t *first_free_cluster) { @@ -1705,6 +1919,7 @@ static int64_t alloc_clusters_imrt(BlockDriverState *bs, int64_t cluster = *first_free_cluster, i; bool first_gap = true; int contiguous_free_clusters; + int ret; /* Starting at *first_free_cluster, find a range of at least cluster_count * continuously free clusters */ @@ -1713,7 +1928,7 @@ static int64_t alloc_clusters_imrt(BlockDriverState *bs, contiguous_free_clusters < cluster_count; cluster++) { - if (!(*refcount_table)[cluster]) { + if (!s->get_refcount(*refcount_table, cluster)) { contiguous_free_clusters++; if (first_gap) { /* If this is the first free cluster found, update @@ -1734,34 +1949,24 @@ static int64_t alloc_clusters_imrt(BlockDriverState *bs, /* If no such range could be found, grow the in-memory refcount table * accordingly to append free clusters at the end of the image */ if (contiguous_free_clusters < cluster_count) { - int64_t old_imrt_nb_clusters = *imrt_nb_clusters; - uint16_t *new_refcount_table; - /* contiguous_free_clusters clusters are already empty at the image end; * we need cluster_count clusters; therefore, we have to allocate * cluster_count - contiguous_free_clusters new clusters at the end of * the image (which is the current value of cluster; note that cluster * may exceed old_imrt_nb_clusters if *first_free_cluster pointed beyond * the image end) */ - *imrt_nb_clusters = cluster + cluster_count - contiguous_free_clusters; - new_refcount_table = g_try_realloc(*refcount_table, - *imrt_nb_clusters * - sizeof(**refcount_table)); - if (!new_refcount_table) { - *imrt_nb_clusters = old_imrt_nb_clusters; - return -ENOMEM; + ret = realloc_refcount_array(s, refcount_table, imrt_nb_clusters, + cluster + cluster_count + - contiguous_free_clusters); + if (ret < 0) { + return ret; } - *refcount_table = new_refcount_table; - - memset(*refcount_table + old_imrt_nb_clusters, 0, - (*imrt_nb_clusters - old_imrt_nb_clusters) * - sizeof(**refcount_table)); } /* Go back to the first free cluster */ cluster -= contiguous_free_clusters; for (i = 0; i < cluster_count; i++) { - (*refcount_table)[cluster + i] = 1; + s->set_refcount(*refcount_table, cluster + i, 1); } return cluster << s->cluster_bits; @@ -1777,7 +1982,7 @@ static int64_t alloc_clusters_imrt(BlockDriverState *bs, */ static int rebuild_refcount_structure(BlockDriverState *bs, BdrvCheckResult *res, - uint16_t **refcount_table, + void **refcount_table, int64_t *nb_clusters) { BDRVQcowState *s = bs->opaque; @@ -1785,8 +1990,8 @@ static int rebuild_refcount_structure(BlockDriverState *bs, int64_t refblock_offset, refblock_start, refblock_index; uint32_t reftable_size = 0; uint64_t *on_disk_reftable = NULL; - uint16_t *on_disk_refblock; - int i, ret = 0; + void *on_disk_refblock; + int ret = 0; struct { uint64_t reftable_offset; uint32_t reftable_clusters; @@ -1796,7 +2001,7 @@ static int rebuild_refcount_structure(BlockDriverState *bs, write_refblocks: for (; cluster < *nb_clusters; cluster++) { - if (!(*refcount_table)[cluster]) { + if (!s->get_refcount(*refcount_table, cluster)) { continue; } @@ -1869,17 +2074,13 @@ write_refblocks: goto fail; } - on_disk_refblock = qemu_blockalign0(bs->file, s->cluster_size); - for (i = 0; i < s->refcount_block_size && - refblock_start + i < *nb_clusters; i++) - { - on_disk_refblock[i] = - cpu_to_be16((*refcount_table)[refblock_start + i]); - } + /* The size of *refcount_table is always cluster-aligned, therefore the + * write operation will not overflow */ + on_disk_refblock = (void *)((char *) *refcount_table + + refblock_index * s->cluster_size); ret = bdrv_write(bs->file, refblock_offset / BDRV_SECTOR_SIZE, - (void *)on_disk_refblock, s->cluster_sectors); - qemu_vfree(on_disk_refblock); + on_disk_refblock, s->cluster_sectors); if (ret < 0) { fprintf(stderr, "ERROR writing refblock: %s\n", strerror(-ret)); goto fail; @@ -1974,7 +2175,7 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, BDRVQcowState *s = bs->opaque; BdrvCheckResult pre_compare_res; int64_t size, highest_cluster, nb_clusters; - uint16_t *refcount_table = NULL; + void *refcount_table = NULL; bool rebuild = false; int ret; @@ -2023,7 +2224,7 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, /* Because the old reftable has been exchanged for a new one the * references have to be recalculated */ rebuild = false; - memset(refcount_table, 0, nb_clusters * sizeof(uint16_t)); + memset(refcount_table, 0, refcount_array_byte_size(s, nb_clusters)); ret = calculate_refcounts(bs, res, 0, &rebuild, &refcount_table, &nb_clusters); if (ret < 0) { |