Re: [Qemu-devel] [PATCH v3 5/5] block/rbd: add support for 'mon_host', 'auth_supported' via QAPI

[Markus Armbruster]

Jeff Cody <address@hidden> writes:

> This adds support for three additional options that may be specified
> by QAPI in blockdev-add:
>
>     server: host, port
>     auth method: either 'cephx' or 'none'
>
> The "server" and "auth-supported" QAPI parameters are arrays.  To conform
> with the rados API, the array items are join as a single string with a ';'
> character as a delimiter when setting the configuration values.
>
> Signed-off-by: Jeff Cody <address@hidden>
> ---
>  block/rbd.c          | 119 
> +++++++++++++++++++++++++++++++++++++++++++++++++++
>  qapi/block-core.json |  29 +++++++++++++
>  2 files changed, 148 insertions(+)
>
> diff --git a/block/rbd.c b/block/rbd.c
> index cc43f42..dfa52cc 100644
> --- a/block/rbd.c
> +++ b/block/rbd.c
> @@ -405,6 +405,19 @@ static QemuOptsList runtime_opts = {
>              .type = QEMU_OPT_STRING,
>              .help = "Legacy rados key/value option parameters",
>          },
> +        {
> +            .name = "host",
> +            .type = QEMU_OPT_STRING,
> +        },
> +        {
> +            .name = "port",
> +            .type = QEMU_OPT_STRING,
> +        },
> +        {
> +            .name = "auth",
> +            .type = QEMU_OPT_STRING,
> +            .help = "Supported authentication method, either cephx or none",
> +        },
>          { /* end of list */ }
>      },
>  };
> @@ -565,14 +578,89 @@ static void qemu_rbd_complete_aio(RADOSCB *rcb)
>      qemu_aio_unref(acb);
>  }
>  
> +#define RBD_MON_HOST          0
> +#define RBD_AUTH_SUPPORTED    1

Blank line here, please.

> +static char *qemu_rbd_array_opts(QDict *options, const char *prefix, int 
> type,
> +                                 Error **errp)
> +{
> +    size_t num_entries;
> +    QemuOpts *opts = NULL;
> +    QDict *sub_options;
> +    const char *host;
> +    const char *port;
> +    char *str;
> +    char *rados_str = NULL;
> +    Error *local_err = NULL;
> +
> +    assert(type == RBD_MON_HOST || type == RBD_AUTH_SUPPORTED);
> +
> +    num_entries = qdict_array_entries(options, prefix);

Can this fail?

> +
> +    if (num_entries) {

Superfluous conditional: if !num_entries, the loop rejects.

> +        for (int i = 0; i < num_entries; i++) {
> +            char *tmp = NULL;
> +            const char *value;
> +            char *rados_str_tmp;
> +
> +            str = g_strdup_printf("%s%d.", prefix, i);
> +            qdict_extract_subqdict(options, &sub_options, str);
> +            g_free(str);
> +
> +            opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
> +            qemu_opts_absorb_qdict(opts, sub_options, &local_err);
> +            QDECREF(sub_options);
> +            if (local_err) {
> +                error_propagate(errp, local_err);
> +                goto exit;

Hmm.  Unless this is the first iteration, rados_str is already non-null,
i.e. we fail and return a string the caller must free.  That's bad
practice; it's better to return NULL on failre.

> +            }
> +
> +            if (type == RBD_MON_HOST) {
> +                host = qemu_opt_get(opts, "host");
> +                port = qemu_opt_get(opts, "port");
> +
> +                value = host;
> +                if (port) {
> +                    tmp = g_strdup_printf("%s:%s", host, port);

Problematic when @host is numeric IPv6.  What syntax does ceph expect in
that case?

> +                    value = tmp;
> +                }
> +            } else {
> +                value = qemu_opt_get(opts, "auth");
> +            }
> +
> +
> +            /* each iteration in the for loop will build upon the string,
> +             * and if rados_str is NULL then it is our first pass */
> +            if (rados_str) {
> +                /* separate options with ';', as that  is what 
> rados_conf_set()
> +                 * requires */
> +                rados_str_tmp = rados_str;
> +                rados_str = g_strdup_printf("%s;%s", rados_str_tmp, value);
> +                g_free(rados_str_tmp);

I'd make rados_str a GString.  But your code isn't wrong.

> +            } else {
> +                rados_str = g_strdup(value);
> +            }
> +
> +            g_free(tmp);

Aha, @tmp is just for getting the g_strdup_printf() freed.  Rename to
strbuf?

> +            qemu_opts_del(opts);
> +            opts = NULL;
> +        }
> +    }
> +
> +exit:
> +    qemu_opts_del(opts);
> +    return rados_str;
> +}
> +
>  static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
>                           Error **errp)
>  {
>      BDRVRBDState *s = bs->opaque;
>      const char *pool, *snap, *conf, *clientname, *name, *keypairs;
> +    const char *auth_supported;
>      const char *secretid;
>      QemuOpts *opts;
>      Error *local_err = NULL;
> +    char *mon_host = NULL;
>      int r;
>  
>      opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
> @@ -583,6 +671,22 @@ static int qemu_rbd_open(BlockDriverState *bs, QDict 
> *options, int flags,
>          return -EINVAL;
>      }
>  
> +   auth_supported = qemu_rbd_array_opts(options, "auth-supported.",

Indentation's off.

> +                                         RBD_AUTH_SUPPORTED, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        r = -EINVAL;
> +        goto failed_opts;
> +    }
> +
> +    mon_host = qemu_rbd_array_opts(options, "server.",
> +                                   RBD_MON_HOST, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        r = -EINVAL;
> +        goto failed_opts;
> +    }
> +
>      secretid = qemu_opt_get(opts, "password-secret");
>  
>      pool           = qemu_opt_get(opts, "pool");
> @@ -615,6 +719,20 @@ static int qemu_rbd_open(BlockDriverState *bs, QDict 
> *options, int flags,
>          goto failed_shutdown;
>      }
>  
> +    if (mon_host) {
> +        r = rados_conf_set(s->cluster, "mon_host", mon_host);
> +        if (r < 0) {
> +            goto failed_shutdown;
> +        }
> +    }
> +
> +    if (auth_supported) {
> +        r = rados_conf_set(s->cluster, "auth_supported", auth_supported);
> +        if (r < 0) {
> +            goto failed_shutdown;
> +        }
> +    }
> +
>      if (qemu_rbd_set_auth(s->cluster, secretid, errp) < 0) {
>          r = -EIO;
>          goto failed_shutdown;
> @@ -663,6 +781,7 @@ failed_shutdown:
>      g_free(s->snap);
>  failed_opts:
>      qemu_opts_del(opts);
> +    g_free(mon_host);

Need to free auth_supported.

>      return r;
>  }
>  
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index f152953..5f74f92 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -2666,6 +2666,28 @@
>              '*header-digest': 'IscsiHeaderDigest',
>              '*timeout': 'int' } }
>  
> +
> +##
> +# @RbdAuthSupport:
> +#
> +# An enumeration of RBD auth support
> +#
> +# Since: 2.9
> +##
> +{ 'enum': 'RbdAuthSupport',
> +  'data': [ 'cephx', 'none' ] }
> +
> +
> +##
> +# @RbdAuthMethod:
> +#
> +# An enumeration of rados auth_supported types
> +#
> +# Since: 2.9
> +##
> +{ 'struct': 'RbdAuthMethod',
> +  'data': { 'auth': 'RbdAuthSupport' } }
> +
>  ##
>  # @BlockdevOptionsRbd:
>  #
> @@ -2681,6 +2703,11 @@
>  #
>  # @user:               #optional Ceph id name.
>  #
> +# @server:             #optional Monitor host address and port.  This maps
> +#                      to the "mon_host" Ceph option.
> +#
> +# @auth-supported:     #optional Authentication supported.
> +#
>  # @password-secret:    #optional The ID of a QCryptoSecret object providing
>  #                      the password for the login.
>  #
> @@ -2692,6 +2719,8 @@
>              '*conf': 'str',
>              '*snapshot': 'str',
>              '*user': 'str',
> +            '*server': ['InetSocketAddress'],
> +            '*auth-supported': ['RbdAuthMethod'],
>              '*password-secret': 'str' } }
>  
>  ##