Signed-off-by: Dong Xu Wang <wdon...@linux.vnet.ibm.com>
---
block/qcow2.c | 265 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 265 insertions(+)
diff --git a/block/qcow2.c b/block/qcow2.c
index 3376901..1c3249d 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1460,6 +1460,218 @@ static int qcow2_create(const char *filename,
QEMUOptionParameter *options)
cluster_size, prealloc, options, version);
}
+static int qcow2_create2_new(const char *filename, int64_t total_size,
+ char *backing_file, char *backing_format,
+ int flags, size_t cluster_size, int prealloc,
+ QemuOpts *opts, int version)
+{
+ /* Calculate cluster_bits */
+ int cluster_bits;
+ int ret = 0;
+ cluster_bits = ffs(cluster_size) - 1;
+ if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS ||
+ (1 << cluster_bits) != cluster_size) {
+ error_report(
+ "Cluster size must be a power of two between %d and %dk",
+ 1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10));
+ ret = -EINVAL;
+ goto finish;
+ }
+
+ /*
+ * Open the image file and write a minimal qcow2 header.
+ *
+ * We keep things simple and start with a zero-sized image. We also
+ * do without refcount blocks or a L1 table for now. We'll fix the
+ * inconsistency later.
+ *
+ * We do need a refcount table because growing the refcount table means
+ * allocating two new refcount blocks - the seconds of which would be at
+ * 2 GB for 64k clusters, and we don't want to have a 2 GB initial file
+ * size for any qcow2 image.
+ */
+ BlockDriverState *bs;
+ QCowHeader header;
+ uint8_t *refcount_table;
+
+ ret = bdrv_create_file_new(filename, opts);
+ if (ret < 0) {
+ goto finish;
+ }
+
+ ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR);
+ if (ret < 0) {
+ goto finish;
+ }
+
+ /* Write the header */
+ memset(&header, 0, sizeof(header));
+ header.magic = cpu_to_be32(QCOW_MAGIC);
+ header.version = cpu_to_be32(version);
+ header.cluster_bits = cpu_to_be32(cluster_bits);
+ header.size = cpu_to_be64(0);
+ header.l1_table_offset = cpu_to_be64(0);
+ header.l1_size = cpu_to_be32(0);
+ header.refcount_table_offset = cpu_to_be64(cluster_size);
+ header.refcount_table_clusters = cpu_to_be32(1);
+ header.refcount_order = cpu_to_be32(3 + REFCOUNT_SHIFT);
+ header.header_length = cpu_to_be32(sizeof(header));
+
+ if (flags & BLOCK_FLAG_ENCRYPT) {
+ header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
+ } else {
+ header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
+ }
+
+ if (flags & BLOCK_FLAG_LAZY_REFCOUNTS) {
+ header.compatible_features |=
+ cpu_to_be64(QCOW2_COMPAT_LAZY_REFCOUNTS);
+ }
+
+ ret = bdrv_pwrite(bs, 0, &header, sizeof(header));
+ if (ret < 0) {
+ goto out;
+ }
+
+ /* Write an empty refcount table */
+ refcount_table = g_malloc0(cluster_size);
+ ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size);
+ g_free(refcount_table);
+
+ if (ret < 0) {
+ goto out;
+ }
+
+ bdrv_close(bs);
+
+ /*
+ * And now open the image and make it consistent first (i.e. increase the
+ * refcount of the cluster that is occupied by the header and the refcount
+ * table)
+ */
+ BlockDriver *drv = bdrv_find_format("qcow2");
+ assert(drv != NULL);
+ ret = bdrv_open(bs, filename, NULL,
+ BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv);
+ if (ret < 0) {
+ goto out;
+ }
+
+ ret = qcow2_alloc_clusters(bs, 2 * cluster_size);
+ if (ret < 0) {
+ goto out;
+
+ } else if (ret != 0) {
+ error_report("Huh, first cluster in empty image is already in use?");
+ abort();
+ }
+
+ /* Okay, now that we have a valid image, let's give it the right size */
+ ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE);
+ if (ret < 0) {
+ goto out;
+ }
+
+ /* Want a backing file? There you go.*/
+ if (backing_file) {
+ ret = bdrv_change_backing_file(bs, backing_file, backing_format);
+ if (ret < 0) {
+ goto out;
+ }
+ }
+
+ /* And if we're supposed to preallocate metadata, do that now */
+ if (prealloc) {
+ BDRVQcowState *s = bs->opaque;
+ qemu_co_mutex_lock(&s->lock);
+ ret = preallocate(bs);
+ qemu_co_mutex_unlock(&s->lock);
+ if (ret < 0) {
+ goto out;
+ }
+ }
+
+ ret = 0;
+out:
+ bdrv_delete(bs);
+finish:
+ g_free(backing_file);
+ g_free(backing_format);
+ return ret;
+}
+
+static int qcow2_create_new(const char *filename, QemuOpts *opts)
+{
+ char *backing_file = NULL;
+ char *backing_fmt = NULL;
+ uint64_t sectors = 0;
+ int flags = 0;
+ size_t cluster_size = DEFAULT_CLUSTER_SIZE;
+ int prealloc = 0;
+ int version = 2;
+ char *buf;
+ int ret = 0;
+
+ /* Read out options */
+ sectors = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0) / 512;
+ backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
+ backing_fmt = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FMT);
+ if (qemu_opt_get_bool_del(opts, BLOCK_OPT_ENCRYPT, false)) {
+ flags |= BLOCK_FLAG_ENCRYPT;
+ }
+ cluster_size = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE,
+ DEFAULT_CLUSTER_SIZE);
+ buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);
+ if (!buf || !strcmp(buf, "off")) {
+ prealloc = 0;
+ } else if (!strcmp(buf, "metadata")) {
+ prealloc = 1;
+ } else {
+ fprintf(stderr, "Invalid preallocation mode: '%s'\n",
+ buf);
+ ret = -EINVAL;
+ goto finish;
+ }
+ g_free(buf);
+ buf = qemu_opt_get_del(opts, BLOCK_OPT_COMPAT_LEVEL);
+ if (!buf || !strcmp(buf, "0.10")) {
+ version = 2;
+ } else if (!strcmp(buf, "1.1")) {
+ version = 3;
+ } else {
+ fprintf(stderr, "Invalid compatibility level: '%s'\n",
+ buf);
+ ret = -EINVAL;
+ goto finish;
+ }
+
+ if (qemu_opt_get_bool_del(opts, BLOCK_OPT_LAZY_REFCOUNTS, false)) {
+ flags |= BLOCK_FLAG_LAZY_REFCOUNTS;
+ }
+
+ if (backing_file && prealloc) {
+ fprintf(stderr, "Backing file and preallocation cannot be used at "
+ "the same time\n");
+ ret = -EINVAL;
+ goto finish;
+ }
+
+ if (version < 3 && (flags & BLOCK_FLAG_LAZY_REFCOUNTS)) {
+ fprintf(stderr, "Lazy refcounts only supported with compatibility "
+ "level 1.1 and above (use compat=1.1 or greater)\n");
+ ret = -EINVAL;
+ goto finish;
+ }
+
+ return qcow2_create2_new(filename, sectors, backing_file, backing_fmt,
flags,
+ cluster_size, prealloc, opts, version);
+finish:
+ g_free(backing_file);
+ g_free(backing_fmt);
+ g_free(buf);
+ return ret;
+}
+
static int qcow2_make_empty(BlockDriverState *bs)
{
#if 0
@@ -1777,6 +1989,57 @@ static QEMUOptionParameter qcow2_create_options[] = {
{ NULL }
};
+static QemuOptsList qcow2_create_opts = {
+ .name = "qcow2-create-opts",
+ .head = QTAILQ_HEAD_INITIALIZER(qcow2_create_opts.head),
+ .desc = {
+ {
+ .name = BLOCK_OPT_SIZE,
+ .type = QEMU_OPT_SIZE,
+ .help = "Virtual disk size"
+ },
+ {
+ .name = BLOCK_OPT_COMPAT_LEVEL,
+ .type = QEMU_OPT_STRING,
+ .help = "Compatibility level (0.10 or 1.1)"
+ },
+ {
+ .name = BLOCK_OPT_BACKING_FILE,
+ .type = QEMU_OPT_STRING,
+ .help = "File name of a base image"
+ },
+ {
+ .name = BLOCK_OPT_BACKING_FMT,
+ .type = QEMU_OPT_STRING,
+ .help = "Image format of the base image"
+ },
+ {
+ .name = BLOCK_OPT_ENCRYPT,
+ .type = QEMU_OPT_BOOL,
+ .help = "Encrypt the image",
+ .def_value_str = "off"
+ },
+ {
+ .name = BLOCK_OPT_CLUSTER_SIZE,
+ .type = QEMU_OPT_SIZE,
+ .help = "qcow2 cluster size",
+ .def_value_str = stringify(DEFAULT_CLUSTER_SIZE)
+ },
+ {
+ .name = BLOCK_OPT_PREALLOC,
+ .type = QEMU_OPT_STRING,
+ .help = "Preallocation mode (allowed values: off, metadata)"
+ },
+ {
+ .name = BLOCK_OPT_LAZY_REFCOUNTS,
+ .type = QEMU_OPT_BOOL,
+ .help = "Postpone refcount updates",
+ .def_value_str = "off"
+ },
+ { /* end of list */ }
+ }
+};
+
static BlockDriver bdrv_qcow2 = {
.format_name = "qcow2",
.instance_size = sizeof(BDRVQcowState),
@@ -1785,6 +2048,7 @@ static BlockDriver bdrv_qcow2 = {
.bdrv_close = qcow2_close,
.bdrv_reopen_prepare = qcow2_reopen_prepare,
.bdrv_create = qcow2_create,
+ .bdrv_create_new = qcow2_create_new,
.bdrv_has_zero_init = bdrv_has_zero_init_1,
.bdrv_co_is_allocated = qcow2_co_is_allocated,
.bdrv_set_key = qcow2_set_key,
@@ -1814,6 +2078,7 @@ static BlockDriver bdrv_qcow2 = {
.bdrv_invalidate_cache = qcow2_invalidate_cache,
.create_options = qcow2_create_options,
+ .bdrv_create_opts = &qcow2_create_opts,
.bdrv_check = qcow2_check,
};
--
1.7.11.7
