Re: [Qemu-devel] [PATCH v5 2/4] rbd: allow configuration of rados from the rbd filename

[Josh Durgin <josh.durgin@dreamhost.com>]

On 05/26/2011 01:13 AM, Kevin Wolf wrote:
> Am 25.05.2011 22:34, schrieb Josh Durgin:
>> The new format is rbd:pool/image[@snapshot][:option1=value1[:option2=value2...]]
>> Each option is used to configure rados, and may be any Ceph option, or "conf".
>> The "conf" option specifies a Ceph configuration file to read.
>>
>> This allows rbd volumes from more than one Ceph cluster to be used by
>> specifying different monitor addresses, as well as having different
>> logging levels or locations for different volumes.
>>
>> Signed-off-by: Josh Durgin<josh.durgin@dreamhost.com>
>> ---
>>   block/rbd.c |  119 ++++++++++++++++++++++++++++++++++++++++++++++++++--------
>>   1 files changed, 102 insertions(+), 17 deletions(-)
>>
>> diff --git a/block/rbd.c b/block/rbd.c
>> index 2cee70d..d346a21 100644
>> --- a/block/rbd.c
>> +++ b/block/rbd.c
>> @@ -23,13 +23,17 @@
>>   /*
>>    * When specifying the image filename use:
>>    *
>> - * rbd:poolname/devicename
>> + * rbd:poolname/devicename[@snapshotname][:option1=value1[:option2=value2...]]
>>    *
>>    * poolname must be the name of an existing rados pool
>>    *
>>    * devicename is the basename for all objects used to
>>    * emulate the raw device.
>>    *
>> + * Each option given is used to configure rados, and may be
>> + * any Ceph option, or "conf". The "conf" option specifies
>> + * a Ceph configuration file to read.
>> + *
>>    * Metadata information (image size, ...) is stored in an
>>    * object with the name "devicename.rbd".
>>    *
>> @@ -123,7 +127,8 @@ static int qemu_rbd_next_tok(char *dst, int dst_len,
>>   static int qemu_rbd_parsename(const char *filename,
>>                                 char *pool, int pool_len,
>>                                 char *snap, int snap_len,
>> -                              char *name, int name_len)
>> +                              char *name, int name_len,
>> +                              char *conf, int conf_len)
>>   {
>>       const char *start;
>>       char *p, *buf;
>> @@ -135,28 +140,84 @@ static int qemu_rbd_parsename(const char *filename,
>>
>>       buf = qemu_strdup(start);
>>       p = buf;
>> +    *snap = '\0';
>> +    *conf = '\0';
>>
>>       ret = qemu_rbd_next_tok(pool, pool_len, p, '/', "pool name",&p);
>>       if (ret<  0 || !p) {
>>           ret = -EINVAL;
>>           goto done;
>>       }
>> -    ret = qemu_rbd_next_tok(name, name_len, p, '@', "object name",&p);
>> -    if (ret<  0) {
>> -        goto done;
>> +
>> +    if (strchr(p, '@')) {
>> +        ret = qemu_rbd_next_tok(name, name_len, p, '@', "object name",&p);
>> +        if (ret<  0) {
>> +            goto done;
>> +        }
>> +        ret = qemu_rbd_next_tok(snap, snap_len, p, ':', "snap name",&p);
>> +    } else {
>> +        ret = qemu_rbd_next_tok(name, name_len, p, ':', "object name",&p);
>>       }
>> -    if (!p) {
>> -        *snap = '\0';
>> +    if (ret<  0 || !p) {
>>           goto done;
>>       }
>>
>> -    ret = qemu_rbd_next_tok(snap, snap_len, p, '\0', "snap name",&p);
>> +    ret = qemu_rbd_next_tok(conf, conf_len, p, '\0', "configuration",&p);
>>
>>   done:
>>       qemu_free(buf);
>>       return ret;
>>   }
>>
>> +static int qemu_rbd_set_conf(rados_t cluster, const char *conf)
>> +{
>> +    char *p, *buf;
>> +    char name[RBD_MAX_CONF_NAME_SIZE];
>> +    char value[RBD_MAX_CONF_VAL_SIZE];
>> +    int ret = 0;
>> +
>> +    buf = qemu_strdup(conf);
>> +    p = buf;
>> +
>> +    while (p) {
>> +        ret = qemu_rbd_next_tok(name, sizeof(name), p,
>> +                                '=', "conf option name",&p);
>> +        if (ret<  0) {
>> +            break;
>> +        }
>> +
>> +        if (!p) {
>> +            error_report("conf option %s has no value", name);
>> +            ret = -EINVAL;
>> +            break;
>> +        }
>> +
>> +        ret = qemu_rbd_next_tok(value, sizeof(value), p,
>> +                                ':', "conf option value",&p);
>> +        if (ret<  0) {
>> +            break;
>> +        }
>> +
>> +        if (strncmp(name, "conf", strlen("conf"))) {
>
> Do you really only want to check if name _starts_ with "conf"?
>
> Kevin

That should just be strcmp.

Josh