Re: [RFC PATCH 05/18] qemu-storage-daemon: Add --blockdev option

[Markus Armbruster]

Kevin Wolf <address@hidden> writes:

> This adds a --blockdev option to the storage daemon that works the same
> as the -blockdev option of the system emulator.
>
> In order to be able to link with blockdev.o, we also need to change
> stream.o from common-obj to block-obj, which is where all other block
> jobs already are.
>
> Signed-off-by: Kevin Wolf <address@hidden>
> ---
>  qemu-storage-daemon.c | 29 +++++++++++++++++++++++++++++
>  Makefile              |  5 ++++-
>  Makefile.objs         |  7 +++++++
>  block/Makefile.objs   |  2 +-
>  4 files changed, 41 insertions(+), 2 deletions(-)
>
> diff --git a/qemu-storage-daemon.c b/qemu-storage-daemon.c
> index 48d6af43a6..904e3c3a46 100644
> --- a/qemu-storage-daemon.c
> +++ b/qemu-storage-daemon.c
> @@ -28,6 +28,10 @@
>  #include "crypto/init.h"
>  
>  #include "qapi/error.h"
> +#include "qapi/qapi-visit-block-core.h"
> +#include "qapi/qapi-commands-block-core.h"
> +#include "qapi/qobject-input-visitor.h"
> +
>  #include "qemu-common.h"
>  #include "qemu-version.h"
>  #include "qemu/config-file.h"
> @@ -53,6 +57,13 @@ static void help(void)
>  "                         specify tracing options\n"
>  "  -V, --version          output version information and exit\n"
>  "\n"
> +"  --blockdev [driver=]<driver>[,node-name=<N>][,discard=ignore|unmap]\n"
> +"             [,cache.direct=on|off][,cache.no-flush=on|off]\n"
> +"             [,read-only=on|off][,auto-read-only=on|off]\n"
> +"             [,force-share=on|off][,detect-zeroes=on|off|unmap]\n"
> +"             [,driver specific parameters...]\n"
> +"                         configure a block backend\n"
> +"\n"
>  "  --object <properties>  define a QOM object such as 'secret' for\n"
>  "                         passwords and/or encryption keys\n"
>  "\n"
> @@ -62,6 +73,7 @@ QEMU_HELP_BOTTOM "\n",
>  
>  enum {
>      OPTION_OBJECT = 256,
> +    OPTION_BLOCKDEV,
>  };
>  
>  static QemuOptsList qemu_object_opts = {
> @@ -82,6 +94,7 @@ static int process_options(int argc, char *argv[], Error 
> **errp)
>      static const struct option long_options[] = {
>          {"help", no_argument, 0, 'h'},
>          {"object", required_argument, 0, OPTION_OBJECT},
> +        {"blockdev", required_argument, 0, OPTION_BLOCKDEV},
>          {"version", no_argument, 0, 'V'},
>          {"trace", required_argument, NULL, 'T'},
>          {0, 0, 0, 0}
> @@ -123,6 +136,22 @@ static int process_options(int argc, char *argv[], Error 
> **errp)
>                  qemu_opts_del(opts);
>                  break;
>              }
> +            break;
> +        case OPTION_BLOCKDEV:
> +            {
> +                Visitor *v;
> +                BlockdevOptions *options;
> +
> +                v = qobject_input_visitor_new_str(optarg, "driver",
> +                                                  &error_fatal);
> +
> +                visit_type_BlockdevOptions(v, NULL, &options, &error_fatal);
> +                visit_free(v);
> +
> +                qmp_blockdev_add(options, &error_fatal);
> +                qapi_free_BlockdevOptions(options);
> +                break;
> +            }
>          }
>      }
>      if (optind != argc) {

Unlike --object, --blockdev is already QAPIfied, albeit crudely.

Similar difference to vl.c as for --object: vl.c records the option for
later processing, while here you process it right away.  Simpler and
saner.

I figure you intend to do all options this way.

Should you explain the difference in a commit message?  A comment?

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