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Diffstat (limited to 'block/qcow2.c')
-rw-r--r--block/qcow2.c129
1 files changed, 117 insertions, 12 deletions
diff --git a/block/qcow2.c b/block/qcow2.c
index 4a9888cc7f..c1abaffa19 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -354,10 +354,67 @@ static QemuOptsList qcow2_runtime_opts = {
.type = QEMU_OPT_BOOL,
.help = "Generate discard requests when other clusters are freed",
},
+ {
+ .name = QCOW2_OPT_OVERLAP,
+ .type = QEMU_OPT_STRING,
+ .help = "Selects which overlap checks to perform from a range of "
+ "templates (none, constant, cached, all)",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_MAIN_HEADER,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the main qcow2 header",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_ACTIVE_L1,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the active L1 table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_ACTIVE_L2,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into an active L2 table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_REFCOUNT_TABLE,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the refcount table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into a refcount block",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the snapshot table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_INACTIVE_L1,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into an inactive L1 table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_INACTIVE_L2,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into an inactive L2 table",
+ },
{ /* end of list */ }
},
};
+static const char *overlap_bool_option_names[QCOW2_OL_MAX_BITNR] = {
+ [QCOW2_OL_MAIN_HEADER_BITNR] = QCOW2_OPT_OVERLAP_MAIN_HEADER,
+ [QCOW2_OL_ACTIVE_L1_BITNR] = QCOW2_OPT_OVERLAP_ACTIVE_L1,
+ [QCOW2_OL_ACTIVE_L2_BITNR] = QCOW2_OPT_OVERLAP_ACTIVE_L2,
+ [QCOW2_OL_REFCOUNT_TABLE_BITNR] = QCOW2_OPT_OVERLAP_REFCOUNT_TABLE,
+ [QCOW2_OL_REFCOUNT_BLOCK_BITNR] = QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK,
+ [QCOW2_OL_SNAPSHOT_TABLE_BITNR] = QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE,
+ [QCOW2_OL_INACTIVE_L1_BITNR] = QCOW2_OPT_OVERLAP_INACTIVE_L1,
+ [QCOW2_OL_INACTIVE_L2_BITNR] = QCOW2_OPT_OVERLAP_INACTIVE_L2,
+};
+
static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
@@ -368,6 +425,8 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
Error *local_err = NULL;
uint64_t ext_end;
uint64_t l1_vm_state_index;
+ const char *opt_overlap_check;
+ int overlap_check_template = 0;
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
if (ret < 0) {
@@ -631,6 +690,33 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
s->discard_passthrough[QCOW2_DISCARD_OTHER] =
qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false);
+ opt_overlap_check = qemu_opt_get(opts, "overlap-check") ?: "cached";
+ if (!strcmp(opt_overlap_check, "none")) {
+ overlap_check_template = 0;
+ } else if (!strcmp(opt_overlap_check, "constant")) {
+ overlap_check_template = QCOW2_OL_CONSTANT;
+ } else if (!strcmp(opt_overlap_check, "cached")) {
+ overlap_check_template = QCOW2_OL_CACHED;
+ } else if (!strcmp(opt_overlap_check, "all")) {
+ overlap_check_template = QCOW2_OL_ALL;
+ } else {
+ error_setg(errp, "Unsupported value '%s' for qcow2 option "
+ "'overlap-check'. Allowed are either of the following: "
+ "none, constant, cached, all", opt_overlap_check);
+ qemu_opts_del(opts);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ s->overlap_check = 0;
+ for (i = 0; i < QCOW2_OL_MAX_BITNR; i++) {
+ /* overlap-check defines a template bitmask, but every flag may be
+ * overwritten through the associated boolean option */
+ s->overlap_check |=
+ qemu_opt_get_bool(opts, overlap_bool_option_names[i],
+ overlap_check_template & (1 << i)) << i;
+ }
+
qemu_opts_del(opts);
if (s->use_lazy_refcounts && s->qcow_version < 3) {
@@ -965,7 +1051,7 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
cur_nr_sectors * 512);
}
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
+ ret = qcow2_pre_write_overlap_check(bs, 0,
cluster_offset + index_in_cluster * BDRV_SECTOR_SIZE,
cur_nr_sectors * BDRV_SECTOR_SIZE);
if (ret < 0) {
@@ -1738,14 +1824,6 @@ static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num,
if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
/* could not compress: write normal cluster */
-
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
- sector_num * BDRV_SECTOR_SIZE,
- s->cluster_sectors * BDRV_SECTOR_SIZE);
- if (ret < 0) {
- goto fail;
- }
-
ret = bdrv_write(bs, sector_num, buf, s->cluster_sectors);
if (ret < 0) {
goto fail;
@@ -1759,8 +1837,7 @@ static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num,
}
cluster_offset &= s->cluster_offset_mask;
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
- cluster_offset, out_len);
+ ret = qcow2_pre_write_overlap_check(bs, 0, cluster_offset, out_len);
if (ret < 0) {
goto fail;
}
@@ -1810,6 +1887,33 @@ static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
return 0;
}
+static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ ImageInfoSpecific *spec_info = g_new(ImageInfoSpecific, 1);
+
+ *spec_info = (ImageInfoSpecific){
+ .kind = IMAGE_INFO_SPECIFIC_KIND_QCOW2,
+ {
+ .qcow2 = g_new(ImageInfoSpecificQCow2, 1),
+ },
+ };
+ if (s->qcow_version == 2) {
+ *spec_info->qcow2 = (ImageInfoSpecificQCow2){
+ .compat = g_strdup("0.10"),
+ };
+ } else if (s->qcow_version == 3) {
+ *spec_info->qcow2 = (ImageInfoSpecificQCow2){
+ .compat = g_strdup("1.1"),
+ .lazy_refcounts = s->compatible_features &
+ QCOW2_COMPAT_LAZY_REFCOUNTS,
+ .has_lazy_refcounts = true,
+ };
+ }
+
+ return spec_info;
+}
+
#if 0
static void dump_refcounts(BlockDriverState *bs)
{
@@ -1888,7 +1992,7 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version)
* support anything different than 4 anyway, there is no point in doing
* so right now; however, we should error out (if qemu supports this in
* the future and this code has not been adapted) */
- error_report("qcow2_downgrade: Image refcount orders other than 4 are"
+ error_report("qcow2_downgrade: Image refcount orders other than 4 are "
"currently not supported.");
return -ENOTSUP;
}
@@ -2130,6 +2234,7 @@ static BlockDriver bdrv_qcow2 = {
.bdrv_snapshot_list = qcow2_snapshot_list,
.bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp,
.bdrv_get_info = qcow2_get_info,
+ .bdrv_get_specific_info = qcow2_get_specific_info,
.bdrv_save_vmstate = qcow2_save_vmstate,
.bdrv_load_vmstate = qcow2_load_vmstate,