block: Image file option amendment
This patch adds the "amend" option to qemu-img which allows changing
image options on existing image files. It also adds the generic bdrv
implementation which is basically just a wrapper for the image format
specific function.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block.c b/block.c
index a325efc..b81d1e2 100644
--- a/block.c
+++ b/block.c
@@ -4579,3 +4579,11 @@
{
notifier_with_return_list_add(&bs->before_write_notifiers, notifier);
}
+
+int bdrv_amend_options(BlockDriverState *bs, QEMUOptionParameter *options)
+{
+ if (bs->drv->bdrv_amend_options == NULL) {
+ return -ENOTSUP;
+ }
+ return bs->drv->bdrv_amend_options(bs, options);
+}
diff --git a/include/block/block.h b/include/block/block.h
index 728ec1a..1c5f939 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -241,6 +241,8 @@
int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
+int bdrv_amend_options(BlockDriverState *bs_new, QEMUOptionParameter *options);
+
/* async block I/O */
typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector,
int sector_num);
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 7c35198..1541777 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -188,6 +188,9 @@
int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result,
BdrvCheckMode fix);
+ int (*bdrv_amend_options)(BlockDriverState *bs,
+ QEMUOptionParameter *options);
+
void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
/* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx
index 0c36e59..da1d965 100644
--- a/qemu-img-cmds.hx
+++ b/qemu-img-cmds.hx
@@ -67,5 +67,11 @@
"resize [-q] filename [+ | -]size")
STEXI
@item resize [-q] @var{filename} [+ | -]@var{size}
+ETEXI
+
+DEF("amend", img_amend,
+ "amend [-q] [-f fmt] -o options filename")
+STEXI
+@item amend [-q] [-f @var{fmt}] -o @var{options} @var{filename}
@end table
ETEXI
diff --git a/qemu-img.c b/qemu-img.c
index 3e5e388..0cf6be2 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -2525,6 +2525,90 @@
return 0;
}
+static int img_amend(int argc, char **argv)
+{
+ int c, ret = 0;
+ char *options = NULL;
+ QEMUOptionParameter *create_options = NULL, *options_param = NULL;
+ const char *fmt = NULL, *filename;
+ bool quiet = false;
+ BlockDriverState *bs = NULL;
+
+ for (;;) {
+ c = getopt(argc, argv, "hqf:o:");
+ if (c == -1) {
+ break;
+ }
+
+ switch (c) {
+ case 'h':
+ case '?':
+ help();
+ break;
+ case 'o':
+ options = optarg;
+ break;
+ case 'f':
+ fmt = optarg;
+ break;
+ case 'q':
+ quiet = true;
+ break;
+ }
+ }
+
+ if (optind != argc - 1) {
+ help();
+ }
+
+ if (!options) {
+ help();
+ }
+
+ filename = argv[argc - 1];
+
+ bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR, true, quiet);
+ if (!bs) {
+ error_report("Could not open image '%s'", filename);
+ ret = -1;
+ goto out;
+ }
+
+ fmt = bs->drv->format_name;
+
+ if (is_help_option(options)) {
+ ret = print_block_option_help(filename, fmt);
+ goto out;
+ }
+
+ create_options = append_option_parameters(create_options,
+ bs->drv->create_options);
+ options_param = parse_option_parameters(options, create_options,
+ options_param);
+ if (options_param == NULL) {
+ error_report("Invalid options for file format '%s'", fmt);
+ ret = -1;
+ goto out;
+ }
+
+ ret = bdrv_amend_options(bs, options_param);
+ if (ret < 0) {
+ error_report("Error while amending options: %s", strerror(-ret));
+ goto out;
+ }
+
+out:
+ if (bs) {
+ bdrv_unref(bs);
+ }
+ free_option_parameters(create_options);
+ free_option_parameters(options_param);
+ if (ret) {
+ return 1;
+ }
+ return 0;
+}
+
static const img_cmd_t img_cmds[] = {
#define DEF(option, callback, arg_string) \
{ option, callback },
diff --git a/qemu-img.texi b/qemu-img.texi
index 43ee4eb..768054e 100644
--- a/qemu-img.texi
+++ b/qemu-img.texi
@@ -350,6 +350,11 @@
After using this command to grow a disk image, you must use file system and
partitioning tools inside the VM to actually begin using the new space on the
device.
+
+@item amend [-f @var{fmt}] -o @var{options} @var{filename}
+
+Amends the image format specific @var{options} for the image file
+@var{filename}. Not all file formats support this operation.
@end table
@c man end
