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vmdk: Implement .bdrv_co_create callback

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This makes VMDK support blockdev-create. The implementation reuses the
image creation code in vmdk_co_create_opts which now acceptes a callback
pointer to "retrieve" BlockBackend pointers from the caller. This way we
separate the logic between file/extent acquisition and initialization.

The QAPI command parameters are mostly the same as the old create_opts
except the dropped legacy @compat6 switch, which is redundant with
@hwversion.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Fam Zheng 2018-05-15 23:36:32 +08:00 committed by Kevin Wolf
parent 5be28490ca
commit 3015372dd0
3 changed files with 401 additions and 135 deletions
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450
block/vmdk.c
View file

@ -1932,33 +1932,56 @@ static int filename_decompose(const char *filename, char *path, char *prefix,
return VMDK_OK;
}
static int coroutine_fn vmdk_co_create_opts(const char *filename, QemuOpts *opts,
Error **errp)
/*
* idx == 0: get or create the descriptor file (also the image file if in a
* non-split format.
* idx >= 1: get the n-th extent if in a split subformat
*/
typedef BlockBackend *(*vmdk_create_extent_fn)(int64_t size,
int idx,
bool flat,
bool split,
bool compress,
bool zeroed_grain,
void *opaque,
Error **errp);
static void vmdk_desc_add_extent(GString *desc,
const char *extent_line_fmt,
int64_t size, const char *filename)
{
int idx = 0;
BlockBackend *new_blk = NULL;
char *basename = g_path_get_basename(filename);
g_string_append_printf(desc, extent_line_fmt,
DIV_ROUND_UP(size, BDRV_SECTOR_SIZE), basename);
g_free(basename);
}
static int coroutine_fn vmdk_co_do_create(int64_t size,
BlockdevVmdkSubformat subformat,
BlockdevVmdkAdapterType adapter_type,
const char *backing_file,
const char *hw_version,
bool compat6,
bool zeroed_grain,
vmdk_create_extent_fn extent_fn,
void *opaque,
Error **errp)
{
int extent_idx;
BlockBackend *blk = NULL;
Error *local_err = NULL;
char *desc = NULL;
int64_t total_size = 0, filesize;
char *adapter_type = NULL;
char *backing_file = NULL;
char *hw_version = NULL;
char *fmt = NULL;
int ret = 0;
bool flat, split, compress;
GString *ext_desc_lines;
char *path = g_malloc0(PATH_MAX);
char *prefix = g_malloc0(PATH_MAX);
char *postfix = g_malloc0(PATH_MAX);
char *desc_line = g_malloc0(BUF_SIZE);
char *ext_filename = g_malloc0(PATH_MAX);
char *desc_filename = g_malloc0(PATH_MAX);
const int64_t split_size = 0x80000000; /* VMDK has constant split size */
const char *desc_extent_line;
int64_t extent_size;
int64_t created_size = 0;
const char *extent_line_fmt;
char *parent_desc_line = g_malloc0(BUF_SIZE);
uint32_t parent_cid = 0xffffffff;
uint32_t number_heads = 16;
bool zeroed_grain = false;
uint32_t desc_offset = 0, desc_len;
const char desc_template[] =
"# Disk DescriptorFile\n"
@ -1982,71 +2005,35 @@ static int coroutine_fn vmdk_co_create_opts(const char *filename, QemuOpts *opts
ext_desc_lines = g_string_new(NULL);
if (filename_decompose(filename, path, prefix, postfix, PATH_MAX, errp)) {
ret = -EINVAL;
goto exit;
}
/* Read out options */
total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
BDRV_SECTOR_SIZE);
adapter_type = qemu_opt_get_del(opts, BLOCK_OPT_ADAPTER_TYPE);
backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
hw_version = qemu_opt_get_del(opts, BLOCK_OPT_HWVERSION);
if (qemu_opt_get_bool_del(opts, BLOCK_OPT_COMPAT6, false)) {
if (strcmp(hw_version, "undefined")) {
if (compat6) {
if (hw_version) {
error_setg(errp,
"compat6 cannot be enabled with hwversion set");
ret = -EINVAL;
goto exit;
}
g_free(hw_version);
hw_version = g_strdup("6");
hw_version = "6";
}
if (strcmp(hw_version, "undefined") == 0) {
g_free(hw_version);
hw_version = g_strdup("4");
}
fmt = qemu_opt_get_del(opts, BLOCK_OPT_SUBFMT);
if (qemu_opt_get_bool_del(opts, BLOCK_OPT_ZEROED_GRAIN, false)) {
zeroed_grain = true;
if (!hw_version) {
hw_version = "4";
}
if (!adapter_type) {
adapter_type = g_strdup("ide");
} else if (strcmp(adapter_type, "ide") &&
strcmp(adapter_type, "buslogic") &&
strcmp(adapter_type, "lsilogic") &&
strcmp(adapter_type, "legacyESX")) {
error_setg(errp, "Unknown adapter type: '%s'", adapter_type);
ret = -EINVAL;
goto exit;
}
if (strcmp(adapter_type, "ide") != 0) {
if (adapter_type != BLOCKDEV_VMDK_ADAPTER_TYPE_IDE) {
/* that's the number of heads with which vmware operates when
creating, exporting, etc. vmdk files with a non-ide adapter type */
number_heads = 255;
}
if (!fmt) {
/* Default format to monolithicSparse */
fmt = g_strdup("monolithicSparse");
} else if (strcmp(fmt, "monolithicFlat") &&
strcmp(fmt, "monolithicSparse") &&
strcmp(fmt, "twoGbMaxExtentSparse") &&
strcmp(fmt, "twoGbMaxExtentFlat") &&
strcmp(fmt, "streamOptimized")) {
error_setg(errp, "Unknown subformat: '%s'", fmt);
ret = -EINVAL;
goto exit;
}
split = !(strcmp(fmt, "twoGbMaxExtentFlat") &&
strcmp(fmt, "twoGbMaxExtentSparse"));
flat = !(strcmp(fmt, "monolithicFlat") &&
strcmp(fmt, "twoGbMaxExtentFlat"));
compress = !strcmp(fmt, "streamOptimized");
split = (subformat == BLOCKDEV_VMDK_SUBFORMAT_TWOGBMAXEXTENTFLAT) ||
(subformat == BLOCKDEV_VMDK_SUBFORMAT_TWOGBMAXEXTENTSPARSE);
flat = (subformat == BLOCKDEV_VMDK_SUBFORMAT_MONOLITHICFLAT) ||
(subformat == BLOCKDEV_VMDK_SUBFORMAT_TWOGBMAXEXTENTFLAT);
compress = subformat == BLOCKDEV_VMDK_SUBFORMAT_STREAMOPTIMIZED;
if (flat) {
desc_extent_line = "RW %" PRId64 " FLAT \"%s\" 0\n";
extent_line_fmt = "RW %" PRId64 " FLAT \"%s\" 0\n";
} else {
desc_extent_line = "RW %" PRId64 " SPARSE \"%s\"\n";
extent_line_fmt = "RW %" PRId64 " SPARSE \"%s\"\n";
}
if (flat && backing_file) {
error_setg(errp, "Flat image can't have backing file");
@ -2058,10 +2045,34 @@ static int coroutine_fn vmdk_co_create_opts(const char *filename, QemuOpts *opts
ret = -ENOTSUP;
goto exit;
}
/* Create extents */
if (split) {
extent_size = split_size;
} else {
extent_size = size;
}
if (!split && !flat) {
created_size = extent_size;
} else {
created_size = 0;
}
/* Get the descriptor file BDS */
blk = extent_fn(created_size, 0, flat, split, compress, zeroed_grain,
opaque, errp);
if (!blk) {
ret = -EIO;
goto exit;
}
if (!split && !flat) {
vmdk_desc_add_extent(ext_desc_lines, extent_line_fmt, created_size,
blk_bs(blk)->filename);
}
if (backing_file) {
BlockBackend *blk;
BlockBackend *backing;
char *full_backing = g_new0(char, PATH_MAX);
bdrv_get_full_backing_filename_from_filename(filename, backing_file,
bdrv_get_full_backing_filename_from_filename(blk_bs(blk)->filename, backing_file,
full_backing, PATH_MAX,
&local_err);
if (local_err) {
@ -2071,93 +2082,64 @@ static int coroutine_fn vmdk_co_create_opts(const char *filename, QemuOpts *opts
goto exit;
}
blk = blk_new_open(full_backing, NULL, NULL,
BDRV_O_NO_BACKING, errp);
backing = blk_new_open(full_backing, NULL, NULL,
BDRV_O_NO_BACKING, errp);
g_free(full_backing);
if (blk == NULL) {
if (backing == NULL) {
ret = -EIO;
goto exit;
}
if (strcmp(blk_bs(blk)->drv->format_name, "vmdk")) {
blk_unref(blk);
if (strcmp(blk_bs(backing)->drv->format_name, "vmdk")) {
error_setg(errp, "Invalid backing file format: %s. Must be vmdk",
blk_bs(backing)->drv->format_name);
blk_unref(backing);
ret = -EINVAL;
goto exit;
}
ret = vmdk_read_cid(blk_bs(blk), 0, &parent_cid);
blk_unref(blk);
ret = vmdk_read_cid(blk_bs(backing), 0, &parent_cid);
blk_unref(backing);
if (ret) {
error_setg(errp, "Failed to read parent CID");
goto exit;
}
snprintf(parent_desc_line, BUF_SIZE,
"parentFileNameHint=\"%s\"", backing_file);
}
/* Create extents */
filesize = total_size;
while (filesize > 0) {
int64_t size = filesize;
if (split && size > split_size) {
size = split_size;
}
if (split) {
snprintf(desc_filename, PATH_MAX, "%s-%c%03d%s",
prefix, flat ? 'f' : 's', ++idx, postfix);
} else if (flat) {
snprintf(desc_filename, PATH_MAX, "%s-flat%s", prefix, postfix);
} else {
snprintf(desc_filename, PATH_MAX, "%s%s", prefix, postfix);
}
snprintf(ext_filename, PATH_MAX, "%s%s", path, desc_filename);
if (vmdk_create_extent(ext_filename, size,
flat, compress, zeroed_grain, NULL, opts, errp)) {
extent_idx = 1;
while (created_size < size) {
BlockBackend *extent_blk;
int64_t cur_size = MIN(size - created_size, extent_size);
extent_blk = extent_fn(cur_size, extent_idx, flat, split, compress,
zeroed_grain, opaque, errp);
if (!extent_blk) {
ret = -EINVAL;
goto exit;
}
filesize -= size;
/* Format description line */
snprintf(desc_line, BUF_SIZE,
desc_extent_line, size / BDRV_SECTOR_SIZE, desc_filename);
g_string_append(ext_desc_lines, desc_line);
vmdk_desc_add_extent(ext_desc_lines, extent_line_fmt, cur_size,
blk_bs(extent_blk)->filename);
created_size += cur_size;
extent_idx++;
blk_unref(extent_blk);
}
/* generate descriptor file */
desc = g_strdup_printf(desc_template,
g_random_int(),
parent_cid,
fmt,
BlockdevVmdkSubformat_str(subformat),
parent_desc_line,
ext_desc_lines->str,
hw_version,
total_size /
size /
(int64_t)(63 * number_heads * BDRV_SECTOR_SIZE),
number_heads,
adapter_type);
BlockdevVmdkAdapterType_str(adapter_type));
desc_len = strlen(desc);
/* the descriptor offset = 0x200 */
if (!split && !flat) {
desc_offset = 0x200;
} else {
ret = bdrv_create_file(filename, opts, &local_err);
if (ret < 0) {
error_propagate(errp, local_err);
goto exit;
}
}
new_blk = blk_new_open(filename, NULL, NULL,
BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL,
&local_err);
if (new_blk == NULL) {
error_propagate(errp, local_err);
ret = -EIO;
goto exit;
}
blk_set_allow_write_beyond_eof(new_blk, true);
ret = blk_pwrite(new_blk, desc_offset, desc, desc_len, 0);
ret = blk_pwrite(blk, desc_offset, desc, desc_len, 0);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not write description");
goto exit;
@ -2165,12 +2147,146 @@ static int coroutine_fn vmdk_co_create_opts(const char *filename, QemuOpts *opts
/* bdrv_pwrite write padding zeros to align to sector, we don't need that
* for description file */
if (desc_offset == 0) {
ret = blk_truncate(new_blk, desc_len, PREALLOC_MODE_OFF, errp);
ret = blk_truncate(blk, desc_len, PREALLOC_MODE_OFF, errp);
if (ret < 0) {
goto exit;
}
}
ret = 0;
exit:
if (new_blk) {
blk_unref(new_blk);
if (blk) {
blk_unref(blk);
}
g_free(desc);
g_free(parent_desc_line);
g_string_free(ext_desc_lines, true);
return ret;
}
typedef struct {
char *path;
char *prefix;
char *postfix;
QemuOpts *opts;
} VMDKCreateOptsData;
static BlockBackend *vmdk_co_create_opts_cb(int64_t size, int idx,
bool flat, bool split, bool compress,
bool zeroed_grain, void *opaque,
Error **errp)
{
BlockBackend *blk = NULL;
BlockDriverState *bs = NULL;
VMDKCreateOptsData *data = opaque;
char *ext_filename = NULL;
char *rel_filename = NULL;
if (idx == 0) {
rel_filename = g_strdup_printf("%s%s", data->prefix, data->postfix);
} else if (split) {
rel_filename = g_strdup_printf("%s-%c%03d%s",
data->prefix,
flat ? 'f' : 's', idx, data->postfix);
} else {
assert(idx == 1);
rel_filename = g_strdup_printf("%s-flat%s", data->prefix, data->postfix);
}
ext_filename = g_strdup_printf("%s%s", data->path, rel_filename);
g_free(rel_filename);
if (vmdk_create_extent(ext_filename, size,
flat, compress, zeroed_grain, &blk, data->opts,
errp)) {
goto exit;
}
bdrv_unref(bs);
exit:
g_free(ext_filename);
return blk;
}
static int coroutine_fn vmdk_co_create_opts(const char *filename, QemuOpts *opts,
Error **errp)
{
Error *local_err = NULL;
char *desc = NULL;
int64_t total_size = 0;
char *adapter_type = NULL;
BlockdevVmdkAdapterType adapter_type_enum;
char *backing_file = NULL;
char *hw_version = NULL;
char *fmt = NULL;
BlockdevVmdkSubformat subformat;
int ret = 0;
char *path = g_malloc0(PATH_MAX);
char *prefix = g_malloc0(PATH_MAX);
char *postfix = g_malloc0(PATH_MAX);
char *desc_line = g_malloc0(BUF_SIZE);
char *ext_filename = g_malloc0(PATH_MAX);
char *desc_filename = g_malloc0(PATH_MAX);
char *parent_desc_line = g_malloc0(BUF_SIZE);
bool zeroed_grain;
bool compat6;
VMDKCreateOptsData data;
if (filename_decompose(filename, path, prefix, postfix, PATH_MAX, errp)) {
ret = -EINVAL;
goto exit;
}
/* Read out options */
total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
BDRV_SECTOR_SIZE);
adapter_type = qemu_opt_get_del(opts, BLOCK_OPT_ADAPTER_TYPE);
backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
hw_version = qemu_opt_get_del(opts, BLOCK_OPT_HWVERSION);
compat6 = qemu_opt_get_bool_del(opts, BLOCK_OPT_COMPAT6, false);
if (strcmp(hw_version, "undefined") == 0) {
g_free(hw_version);
hw_version = g_strdup("4");
}
fmt = qemu_opt_get_del(opts, BLOCK_OPT_SUBFMT);
zeroed_grain = qemu_opt_get_bool_del(opts, BLOCK_OPT_ZEROED_GRAIN, false);
if (adapter_type) {
adapter_type_enum = qapi_enum_parse(&BlockdevVmdkAdapterType_lookup,
adapter_type,
BLOCKDEV_VMDK_ADAPTER_TYPE_IDE,
&local_err);
if (local_err) {
error_propagate(errp, local_err);
ret = -EINVAL;
goto exit;
}
} else {
adapter_type_enum = BLOCKDEV_VMDK_ADAPTER_TYPE_IDE;
}
if (!fmt) {
/* Default format to monolithicSparse */
subformat = BLOCKDEV_VMDK_SUBFORMAT_MONOLITHICSPARSE;
} else {
subformat = qapi_enum_parse(&BlockdevVmdkSubformat_lookup,
fmt,
BLOCKDEV_VMDK_SUBFORMAT_MONOLITHICSPARSE,
&local_err);
if (local_err) {
error_propagate(errp, local_err);
ret = -EINVAL;
goto exit;
}
}
data = (VMDKCreateOptsData){
.prefix = prefix,
.postfix = postfix,
.path = path,
.opts = opts,
};
ret = vmdk_co_do_create(total_size, subformat, adapter_type_enum,
backing_file, hw_version, compat6, zeroed_grain,
vmdk_co_create_opts_cb, &data, errp);
exit:
g_free(adapter_type);
g_free(backing_file);
g_free(hw_version);
@ -2183,7 +2299,84 @@ exit:
g_free(ext_filename);
g_free(desc_filename);
g_free(parent_desc_line);
g_string_free(ext_desc_lines, true);
return ret;
}
static BlockBackend *vmdk_co_create_cb(int64_t size, int idx,
bool flat, bool split, bool compress,
bool zeroed_grain, void *opaque,
Error **errp)
{
int ret;
BlockDriverState *bs;
BlockBackend *blk;
BlockdevCreateOptionsVmdk *opts = opaque;
if (idx == 0) {
bs = bdrv_open_blockdev_ref(opts->file, errp);
} else {
int i;
BlockdevRefList *list = opts->extents;
for (i = 1; i < idx; i++) {
if (!list || !list->next) {
error_setg(errp, "Extent [%d] not specified", i);
return NULL;
}
list = list->next;
}
if (!list) {
error_setg(errp, "Extent [%d] not specified", idx - 1);
return NULL;
}
bs = bdrv_open_blockdev_ref(list->value, errp);
}
if (!bs) {
return NULL;
}
blk = blk_new(BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | BLK_PERM_RESIZE,
BLK_PERM_ALL);
if (blk_insert_bs(blk, bs, errp)) {
bdrv_unref(bs);
return NULL;
}
blk_set_allow_write_beyond_eof(blk, true);
bdrv_unref(bs);
ret = vmdk_init_extent(blk, size, flat, compress, zeroed_grain, errp);
if (ret) {
blk_unref(blk);
blk = NULL;
}
return blk;
}
static int coroutine_fn vmdk_co_create(BlockdevCreateOptions *create_options,
Error **errp)
{
int ret;
BlockdevCreateOptionsVmdk *opts;
opts = &create_options->u.vmdk;
/* Validate options */
if (!QEMU_IS_ALIGNED(opts->size, BDRV_SECTOR_SIZE)) {
error_setg(errp, "Image size must be a multiple of 512 bytes");
ret = -EINVAL;
goto out;
}
ret = vmdk_co_do_create(opts->size,
opts->subformat,
opts->adapter_type,
opts->backing_file,
opts->hwversion,
false,
opts->zeroed_grain,
vmdk_co_create_cb,
opts, errp);
return ret;
out:
return ret;
}
@ -2451,6 +2644,7 @@ static BlockDriver bdrv_vmdk = {
.bdrv_co_pwrite_zeroes = vmdk_co_pwrite_zeroes,
.bdrv_close = vmdk_close,
.bdrv_co_create_opts = vmdk_co_create_opts,
.bdrv_co_create = vmdk_co_create,
.bdrv_co_flush_to_disk = vmdk_co_flush,
.bdrv_co_block_status = vmdk_co_block_status,
.bdrv_get_allocated_file_size = vmdk_get_allocated_file_size,

70
qapi/block-core.json
View file

@ -4137,6 +4137,75 @@
'size': 'size',
'*cluster-size' : 'size' } }
##
# @BlockdevVmdkSubformat:
#
# Subformat options for VMDK images
#
# @monolithicSparse: Single file image with sparse cluster allocation
#
# @monolithicFlat: Single flat data image and a descriptor file
#
# @twoGbMaxExtentSparse: Data is split into 2GB (per virtual LBA) sparse extent
# files, in addition to a descriptor file
#
# @twoGbMaxExtentFlat: Data is split into 2GB (per virtual LBA) flat extent
# files, in addition to a descriptor file
#
# @streamOptimized: Single file image sparse cluster allocation, optimized
# for streaming over network.
#
# Since: 4.0
##
{ 'enum': 'BlockdevVmdkSubformat',
'data': [ 'monolithicSparse', 'monolithicFlat', 'twoGbMaxExtentSparse',
'twoGbMaxExtentFlat', 'streamOptimized'] }
##
# @BlockdevVmdkAdapterType:
#
# Adapter type info for VMDK images
#
# Since: 4.0
##
{ 'enum': 'BlockdevVmdkAdapterType',
'data': [ 'ide', 'buslogic', 'lsilogic', 'legacyESX'] }
##
# @BlockdevCreateOptionsVmdk:
#
# Driver specific image creation options for VMDK.
#
# @file Where to store the new image file. This refers to the image
# file for monolithcSparse and streamOptimized format, or the
# descriptor file for other formats.
# @size Size of the virtual disk in bytes
# @extents Where to store the data extents. Required for monolithcFlat,
# twoGbMaxExtentSparse and twoGbMaxExtentFlat formats. For
# monolithicFlat, only one entry is required; for
# twoGbMaxExtent* formats, the number of entries required is
# calculated as extent_number = virtual_size / 2GB.
# @subformat The subformat of the VMDK image. Default: "monolithicSparse".
# @backing-file The path of backing file. Default: no backing file is used.
# @adapter-type The adapter type used to fill in the descriptor. Default: ide.
# @hwversion Hardware version. The meaningful options are "4" or "6".
# Default: "4".
# @zeroed-grain Whether to enable zeroed-grain feature for sparse subformats.
# Default: false.
#
# Since: 4.0
##
{ 'struct': 'BlockdevCreateOptionsVmdk',
'data': { 'file': 'BlockdevRef',
'size': 'size',
'*extents': ['BlockdevRef'],
'*subformat': 'BlockdevVmdkSubformat',
'*backing-file': 'str',
'*adapter-type': 'BlockdevVmdkAdapterType',
'*hwversion': 'str',
'*zeroed-grain': 'bool' } }
##
# @SheepdogRedundancyType:
#
@ -4331,6 +4400,7 @@
'ssh': 'BlockdevCreateOptionsSsh',
'vdi': 'BlockdevCreateOptionsVdi',
'vhdx': 'BlockdevCreateOptionsVhdx',
'vmdk': 'BlockdevCreateOptionsVmdk',
'vpc': 'BlockdevCreateOptionsVpc'
} }

16
qapi/qapi-schema.json
View file

@ -63,13 +63,15 @@
'query-tpm-types',
'ringbuf-read' ],
'name-case-whitelist': [
'ACPISlotType', # DIMM, visible through query-acpi-ospm-status
'CpuInfoMIPS', # PC, visible through query-cpu
'CpuInfoTricore', # PC, visible through query-cpu
'QapiErrorClass', # all members, visible through errors
'UuidInfo', # UUID, visible through query-uuid
'X86CPURegister32', # all members, visible indirectly through qom-get
'q_obj_CpuInfo-base' # CPU, visible through query-cpu
'ACPISlotType', # DIMM, visible through query-acpi-ospm-status
'CpuInfoMIPS', # PC, visible through query-cpu
'CpuInfoTricore', # PC, visible through query-cpu
'BlockdevVmdkSubformat', # all members, to match VMDK spec spellings
'BlockdevVmdkAdapterType', # legacyESX, to match VMDK spec spellings
'QapiErrorClass', # all members, visible through errors
'UuidInfo', # UUID, visible through query-uuid
'X86CPURegister32', # all members, visible indirectly through qom-get
'q_obj_CpuInfo-base' # CPU, visible through query-cpu
] } }
# Documentation generated with qapi-gen.py is in source order, with