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Diffstat (limited to 'block/qcow2-refcount.c')
-rw-r--r--block/qcow2-refcount.c86
1 files changed, 47 insertions, 39 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 1a85bcd..d853490 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)++;
generated by cgit v1.1 at 2024-11-01 00:56:21 +0000