aboutsummaryrefslogtreecommitdiff
path: root/block/qcow2-cluster.c
diff options
context:
space:
mode:
Diffstat (limited to 'block/qcow2-cluster.c')
-rw-r--r--block/qcow2-cluster.c79
1 files changed, 30 insertions, 49 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 26f9e0e4b8..558c23957f 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -321,8 +321,7 @@ static int count_contiguous_clusters(int nb_clusters, int cluster_size,
/* must be allocated */
first_cluster_type = qcow2_get_cluster_type(first_entry);
assert(first_cluster_type == QCOW2_CLUSTER_NORMAL ||
- (first_cluster_type == QCOW2_CLUSTER_ZERO &&
- (first_entry & L2E_OFFSET_MASK) != 0));
+ first_cluster_type == QCOW2_CLUSTER_ZERO_ALLOC);
for (i = 0; i < nb_clusters; i++) {
uint64_t l2_entry = be64_to_cpu(l2_table[i]) & mask;
@@ -344,13 +343,13 @@ static int count_contiguous_clusters_unallocated(int nb_clusters,
{
int i;
- assert(wanted_type == QCOW2_CLUSTER_ZERO ||
+ assert(wanted_type == QCOW2_CLUSTER_ZERO_PLAIN ||
wanted_type == QCOW2_CLUSTER_UNALLOCATED);
for (i = 0; i < nb_clusters; i++) {
uint64_t entry = be64_to_cpu(l2_table[i]);
QCow2ClusterType type = qcow2_get_cluster_type(entry);
- if (type != wanted_type || entry & L2E_OFFSET_MASK) {
+ if (type != wanted_type) {
break;
}
}
@@ -559,55 +558,36 @@ int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
assert(nb_clusters <= INT_MAX);
type = qcow2_get_cluster_type(*cluster_offset);
+ 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"
+ " in pre-v3 image (L2 offset: %#" PRIx64
+ ", L2 index: %#x)", l2_offset, l2_index);
+ ret = -EIO;
+ goto fail;
+ }
switch (type) {
case QCOW2_CLUSTER_COMPRESSED:
/* Compressed clusters can only be processed one by one */
c = 1;
*cluster_offset &= L2E_COMPRESSED_OFFSET_SIZE_MASK;
break;
- case QCOW2_CLUSTER_ZERO:
- if (s->qcow_version < 3) {
- qcow2_signal_corruption(bs, true, -1, -1, "Zero cluster entry found"
- " in pre-v3 image (L2 offset: %#" PRIx64
- ", L2 index: %#x)", l2_offset, l2_index);
- ret = -EIO;
- goto fail;
- }
- /* Distinguish between pure zero clusters and pre-allocated ones */
- if (*cluster_offset & L2E_OFFSET_MASK) {
- c = count_contiguous_clusters(nb_clusters, s->cluster_size,
- &l2_table[l2_index], QCOW_OFLAG_ZERO);
- *cluster_offset &= L2E_OFFSET_MASK;
- if (offset_into_cluster(s, *cluster_offset)) {
- qcow2_signal_corruption(bs, true, -1, -1,
- "Preallocated zero cluster offset %#"
- PRIx64 " unaligned (L2 offset: %#"
- PRIx64 ", L2 index: %#x)",
- *cluster_offset, l2_offset, l2_index);
- ret = -EIO;
- goto fail;
- }
- } else {
- c = count_contiguous_clusters_unallocated(nb_clusters,
- &l2_table[l2_index],
- QCOW2_CLUSTER_ZERO);
- *cluster_offset = 0;
- }
- break;
+ case QCOW2_CLUSTER_ZERO_PLAIN:
case QCOW2_CLUSTER_UNALLOCATED:
/* how many empty clusters ? */
c = count_contiguous_clusters_unallocated(nb_clusters,
- &l2_table[l2_index],
- QCOW2_CLUSTER_UNALLOCATED);
+ &l2_table[l2_index], type);
*cluster_offset = 0;
break;
+ case QCOW2_CLUSTER_ZERO_ALLOC:
case QCOW2_CLUSTER_NORMAL:
/* how many allocated clusters ? */
c = count_contiguous_clusters(nb_clusters, s->cluster_size,
- &l2_table[l2_index], QCOW_OFLAG_ZERO);
+ &l2_table[l2_index], QCOW_OFLAG_ZERO);
*cluster_offset &= L2E_OFFSET_MASK;
if (offset_into_cluster(s, *cluster_offset)) {
- qcow2_signal_corruption(bs, true, -1, -1, "Data cluster offset %#"
+ qcow2_signal_corruption(bs, true, -1, -1,
+ "Cluster allocation offset %#"
PRIx64 " unaligned (L2 offset: %#" PRIx64
", L2 index: %#x)", *cluster_offset,
l2_offset, l2_index);
@@ -902,7 +882,8 @@ static int count_cow_clusters(BDRVQcow2State *s, int nb_clusters,
break;
case QCOW2_CLUSTER_UNALLOCATED:
case QCOW2_CLUSTER_COMPRESSED:
- case QCOW2_CLUSTER_ZERO:
+ case QCOW2_CLUSTER_ZERO_PLAIN:
+ case QCOW2_CLUSTER_ZERO_ALLOC:
break;
default:
abort();
@@ -1203,8 +1184,8 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset,
* wrong with our code. */
assert(nb_clusters > 0);
- if (qcow2_get_cluster_type(entry) == QCOW2_CLUSTER_ZERO &&
- (entry & L2E_OFFSET_MASK) != 0 && (entry & QCOW_OFLAG_COPIED) &&
+ if (qcow2_get_cluster_type(entry) == QCOW2_CLUSTER_ZERO_ALLOC &&
+ (entry & QCOW_OFLAG_COPIED) &&
(!*host_offset ||
start_of_cluster(s, *host_offset) == (entry & L2E_OFFSET_MASK)))
{
@@ -1536,13 +1517,13 @@ static int discard_single_l2(BlockDriverState *bs, uint64_t offset,
}
break;
- case QCOW2_CLUSTER_ZERO:
- /* Preallocated zero clusters should be discarded in any case */
- if (!full_discard && (old_l2_entry & L2E_OFFSET_MASK) == 0) {
+ case QCOW2_CLUSTER_ZERO_PLAIN:
+ if (!full_discard) {
continue;
}
break;
+ case QCOW2_CLUSTER_ZERO_ALLOC:
case QCOW2_CLUSTER_NORMAL:
case QCOW2_CLUSTER_COMPRESSED:
break;
@@ -1759,13 +1740,13 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
uint64_t l2_entry = be64_to_cpu(l2_table[j]);
int64_t offset = l2_entry & L2E_OFFSET_MASK;
QCow2ClusterType cluster_type = qcow2_get_cluster_type(l2_entry);
- bool preallocated = offset != 0;
- if (cluster_type != QCOW2_CLUSTER_ZERO) {
+ if (cluster_type != QCOW2_CLUSTER_ZERO_PLAIN &&
+ cluster_type != QCOW2_CLUSTER_ZERO_ALLOC) {
continue;
}
- if (!preallocated) {
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
if (!bs->backing) {
/* not backed; therefore we can simply deallocate the
* cluster */
@@ -1800,7 +1781,7 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
"%#" PRIx64 " unaligned (L2 offset: %#"
PRIx64 ", L2 index: %#x)", offset,
l2_offset, j);
- if (!preallocated) {
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
qcow2_free_clusters(bs, offset, s->cluster_size,
QCOW2_DISCARD_ALWAYS);
}
@@ -1810,7 +1791,7 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
ret = qcow2_pre_write_overlap_check(bs, 0, offset, s->cluster_size);
if (ret < 0) {
- if (!preallocated) {
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
qcow2_free_clusters(bs, offset, s->cluster_size,
QCOW2_DISCARD_ALWAYS);
}
@@ -1819,7 +1800,7 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
ret = bdrv_pwrite_zeroes(bs->file, offset, s->cluster_size, 0);
if (ret < 0) {
- if (!preallocated) {
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
qcow2_free_clusters(bs, offset, s->cluster_size,
QCOW2_DISCARD_ALWAYS);
}
generated by cgit v1.2.3 (git 2.26.2) at 2025-02-13 09:36:58 +0000