On 07/11/2012 02:36 PM, Josh Durgin wrote: > On 07/11/2012 07:02 AM, Alex Elder wrote: >> An rbd device's pool name is used to specify the pool to use for an >> rbd image when it gets mapped (via rbd_add()). However, only the >> pool id can be relied on to be invariant--the name of a pool can >> change at any time. >> >> This means that the name of the pool is potentially stale as soon as >> the image is mapped, so it's a bad idea to record this information. >> So only store the pool id, not its name, in an rbd_dev. >> >> Here are a few specific notes about this change: >> - The "pool" name device attribute (/sys/bus/rbd/devices/<N>/pool) >> goes away. In its place is a "pool_id" attribute that provide >> the numeric pool id for the rbd image. > > We're using the pool name for udev to provide a predictable device name > (/dev/rbd/poolname/imagename[@snapname]), so we probably want to keep > the sysfs attribute. I don't think there's a good way for us to detect > pool renames right now though, so we should document that the pool > name reported does not reflect any potential renames. OK. I'll put the "pool" name entry back, but will still include the new "pool_id" entry as well. Do you want me to re-post after that, or can I consider this reviewed? -Alex >> - rbd_add_parse_args() now returns a pointer to a dynamically- >> allocated copy of the pool name taken from the arguments. >> - rbd_add() has been changed to handle freeing the pool name, >> both in error cases and in the normal case after the pool id >> has been recorded. >> >> Signed-off-by: Alex Elder<elder@xxxxxxxxxxx> . . . -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
