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Diffstat (limited to 'block/qcow2.c')
-rw-r--r--block/qcow2.c66
1 files changed, 60 insertions, 6 deletions
diff --git a/block/qcow2.c b/block/qcow2.c
index 7c03d41170..00cda5696b 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1449,6 +1449,12 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
s->subcluster_size = s->cluster_size / s->subclusters_per_cluster;
s->subcluster_bits = ctz32(s->subcluster_size);
+ if (s->subcluster_size < (1 << MIN_CLUSTER_BITS)) {
+ error_setg(errp, "Unsupported subcluster size: %d", s->subcluster_size);
+ ret = -EINVAL;
+ goto fail;
+ }
+
/* Check support for various header values */
if (header.refcount_order > 6) {
error_setg(errp, "Reference count entry width too large; may not "
@@ -2935,6 +2941,11 @@ int qcow2_update_header(BlockDriverState *bs)
.name = "compression type",
},
{
+ .type = QCOW2_FEAT_TYPE_INCOMPATIBLE,
+ .bit = QCOW2_INCOMPAT_EXTL2_BITNR,
+ .name = "extended L2 entries",
+ },
+ {
.type = QCOW2_FEAT_TYPE_COMPATIBLE,
.bit = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
.name = "lazy refcounts",
@@ -3270,7 +3281,8 @@ static int64_t qcow2_calc_prealloc_size(int64_t total_size,
return meta_size + aligned_total_size;
}
-static bool validate_cluster_size(size_t cluster_size, Error **errp)
+static bool validate_cluster_size(size_t cluster_size, bool extended_l2,
+ Error **errp)
{
int cluster_bits = ctz32(cluster_size);
if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS ||
@@ -3280,16 +3292,28 @@ static bool validate_cluster_size(size_t cluster_size, Error **errp)
"%dk", 1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10));
return false;
}
+
+ if (extended_l2) {
+ unsigned min_cluster_size =
+ (1 << MIN_CLUSTER_BITS) * QCOW_EXTL2_SUBCLUSTERS_PER_CLUSTER;
+ if (cluster_size < min_cluster_size) {
+ error_setg(errp, "Extended L2 entries are only supported with "
+ "cluster sizes of at least %u bytes", min_cluster_size);
+ return false;
+ }
+ }
+
return true;
}
-static size_t qcow2_opt_get_cluster_size_del(QemuOpts *opts, Error **errp)
+static size_t qcow2_opt_get_cluster_size_del(QemuOpts *opts, bool extended_l2,
+ Error **errp)
{
size_t cluster_size;
cluster_size = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE,
DEFAULT_CLUSTER_SIZE);
- if (!validate_cluster_size(cluster_size, errp)) {
+ if (!validate_cluster_size(cluster_size, extended_l2, errp)) {
return 0;
}
return cluster_size;
@@ -3403,7 +3427,20 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
cluster_size = DEFAULT_CLUSTER_SIZE;
}
- if (!validate_cluster_size(cluster_size, errp)) {
+ if (!qcow2_opts->has_extended_l2) {
+ qcow2_opts->extended_l2 = false;
+ }
+ if (qcow2_opts->extended_l2) {
+ if (version < 3) {
+ error_setg(errp, "Extended L2 entries are only supported with "
+ "compatibility level 1.1 and above (use version=v3 or "
+ "greater)");
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ if (!validate_cluster_size(cluster_size, qcow2_opts->extended_l2, errp)) {
ret = -EINVAL;
goto out;
}
@@ -3554,6 +3591,11 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
cpu_to_be64(QCOW2_INCOMPAT_COMPRESSION);
}
+ if (qcow2_opts->extended_l2) {
+ header->incompatible_features |=
+ cpu_to_be64(QCOW2_INCOMPAT_EXTL2);
+ }
+
ret = blk_pwrite(blk, 0, header, cluster_size, 0);
g_free(header);
if (ret < 0) {
@@ -3731,6 +3773,7 @@ static int coroutine_fn qcow2_co_create_opts(BlockDriver *drv,
{ BLOCK_OPT_BACKING_FMT, "backing-fmt" },
{ BLOCK_OPT_CLUSTER_SIZE, "cluster-size" },
{ BLOCK_OPT_LAZY_REFCOUNTS, "lazy-refcounts" },
+ { BLOCK_OPT_EXTL2, "extended-l2" },
{ BLOCK_OPT_REFCOUNT_BITS, "refcount-bits" },
{ BLOCK_OPT_ENCRYPT, BLOCK_OPT_ENCRYPT_FORMAT },
{ BLOCK_OPT_COMPAT_LEVEL, "version" },
@@ -4847,11 +4890,14 @@ static BlockMeasureInfo *qcow2_measure(QemuOpts *opts, BlockDriverState *in_bs,
PreallocMode prealloc;
bool has_backing_file;
bool has_luks;
- bool extended_l2 = false; /* Set to false until the option is added */
+ bool extended_l2;
size_t l2e_size;
/* Parse image creation options */
- cluster_size = qcow2_opt_get_cluster_size_del(opts, &local_err);
+ extended_l2 = qemu_opt_get_bool_del(opts, BLOCK_OPT_EXTL2, false);
+
+ cluster_size = qcow2_opt_get_cluster_size_del(opts, extended_l2,
+ &local_err);
if (local_err) {
goto err;
}
@@ -5047,6 +5093,8 @@ static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs,
.corrupt = s->incompatible_features &
QCOW2_INCOMPAT_CORRUPT,
.has_corrupt = true,
+ .has_extended_l2 = true,
+ .extended_l2 = has_subclusters(s),
.refcount_bits = s->refcount_bits,
.has_bitmaps = !!bitmaps,
.bitmaps = bitmaps,
@@ -5775,6 +5823,12 @@ static QemuOptsList qcow2_create_opts = {
.def_value_str = stringify(DEFAULT_CLUSTER_SIZE) \
}, \
{ \
+ .name = BLOCK_OPT_EXTL2, \
+ .type = QEMU_OPT_BOOL, \
+ .help = "Extended L2 tables", \
+ .def_value_str = "off" \
+ }, \
+ { \
.name = BLOCK_OPT_PREALLOC, \
.type = QEMU_OPT_STRING, \
.help = "Preallocation mode (allowed values: off, " \