@@ -332,6 +332,83 @@ static QEMUOptionParameter cow_create_options[] = {
{ NULL }
};
+static int cow_create_new(const char *filename, QemuOpts *opts)
+{
+ struct cow_header_v2 cow_header;
+ struct stat st;
+ int64_t image_sectors = 0;
+ char *image_filename = NULL;
+ int ret;
+ BlockDriverState *cow_bs;
+
+ /* Read out opts */
+ image_sectors = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0) / 512;
+ image_filename = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
+
+ ret = bdrv_create_file_new(filename, opts);
+ if (ret < 0) {
+ goto finish;
+ }
+
+ ret = bdrv_file_open(&cow_bs, filename, NULL, BDRV_O_RDWR);
+ if (ret < 0) {
+ goto finish;
+ }
+
+ memset(&cow_header, 0, sizeof(cow_header));
+ cow_header.magic = cpu_to_be32(COW_MAGIC);
+ cow_header.version = cpu_to_be32(COW_VERSION);
+ if (image_filename) {
+ /* Note: if no file, we put a dummy mtime */
+ cow_header.mtime = cpu_to_be32(0);
+
+ if (stat(image_filename, &st) != 0) {
+ goto mtime_fail;
+ }
+ cow_header.mtime = cpu_to_be32(st.st_mtime);
+ mtime_fail:
+ pstrcpy(cow_header.backing_file, sizeof(cow_header.backing_file),
+ image_filename);
+ }
+ cow_header.sectorsize = cpu_to_be32(512);
+ cow_header.size = cpu_to_be64(image_sectors * 512);
+ ret = bdrv_pwrite(cow_bs, 0, &cow_header, sizeof(cow_header));
+ if (ret < 0) {
+ goto exit;
+ }
+
+ /* resize to include at least all the bitmap */
+ ret = bdrv_truncate(cow_bs,
+ sizeof(cow_header) + ((image_sectors + 7) >> 3));
+ if (ret < 0) {
+ goto exit;
+ }
+
+exit:
+ bdrv_delete(cow_bs);
+finish:
+ g_free(image_filename);
+ return ret;
+}
+
+static QemuOptsList cow_create_opts = {
+ .name = "cow-create-opts",
+ .head = QTAILQ_HEAD_INITIALIZER(cow_create_opts.head),
+ .desc = {
+ {
+ .name = BLOCK_OPT_SIZE,
+ .type = QEMU_OPT_SIZE,
+ .help = "Virtual disk size"
+ },
+ {
+ .name = BLOCK_OPT_BACKING_FILE,
+ .type = QEMU_OPT_STRING,
+ .help = "File name of a base image"
+ },
+ { /* end of list */ }
+ }
+};
+
static BlockDriver bdrv_cow = {
.format_name = "cow",
.instance_size = sizeof(BDRVCowState),
@@ -340,6 +417,7 @@ static BlockDriver bdrv_cow = {
.bdrv_open = cow_open,
.bdrv_close = cow_close,
.bdrv_create = cow_create,
+ .bdrv_create_new = cow_create_new,
.bdrv_has_zero_init = bdrv_has_zero_init_1,
.bdrv_read = cow_co_read,
@@ -347,6 +425,7 @@ static BlockDriver bdrv_cow = {
.bdrv_co_is_allocated = cow_co_is_allocated,
.create_options = cow_create_options,
+ .bdrv_create_opts = &cow_create_opts,
};
static void bdrv_cow_init(void)
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com> --- block/cow.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+)