Re: [PATCH v2 2/2] ceph: add CEPH_IOC_GET_CLUSTER_AND_CLIENT_IDS ioctl cmd support

[Xiubo Li <xiubli@xxxxxxxxxx>]

On 2020/11/10 21:43, Jeff Layton wrote:
> On Tue, 2020-11-10 at 21:34 +0800, Xiubo Li wrote:
> > On 2020/11/10 21:32, Jeff Layton wrote:
> > > On Tue, 2020-11-10 at 21:25 +0800, Xiubo Li wrote:
> > > > On 2020/11/10 20:24, Jeff Layton wrote:
> > > > > On Tue, 2020-11-10 at 18:57 +0800, xiubli@xxxxxxxxxx wrote:
> > > > > > From: Xiubo Li <xiubli@xxxxxxxxxx>
> > > > > >
> > > > > > This ioctl will return the cluster and client ids back to userspace.
> > > > > > With this we can easily know which mountpoint the file belongs to and
> > > > > > also they can help locate the debugfs path quickly.
> > > > > >
> > > > > > URL: https://tracker.ceph.com/issues/48124
> > > > > > Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
> > > > > > ---
> > > > > >     fs/ceph/ioctl.c | 23 +++++++++++++++++++++++
> > > > > >     fs/ceph/ioctl.h | 15 +++++++++++++++
> > > > > >     2 files changed, 38 insertions(+)
> > > > > I know I opened this bug and suggested an ioctl for this, but I think
> > > > > that this may be better presented as new vxattrs. Driving ioctls from
> > > > > scripts is difficult (in particular). An xattr is easier for them to
> > > > > deal with. Maybe:
> > > > >
> > > > >        ceph.clusterid
> > > > >        ceph.clientid
> > > > How about :
> > > >
> > > > [root@lxbceph1 kcephfs]# getfattr -n ceph.local.clusterid file
> > > > # file: file
> > > > ceph.local.clusterid="6ff21dc9-36b0-45a9-bec2-75aeaf0414cf"
> > > >
> > > > [root@lxbceph1 kcephfs]# getfattr -n ceph.local.clientid file
> > > > # file: file
> > > > ceph.local.clientid="client4360"
> > > >
> > > > ??
> > > What does "local" signify in these names?
> > Which means only existing in local client side. If this make no sense I
> > will remove them.
> >
> > Thanks
> >
> > BRs
> Yeah, I don't think it helps anything. I'd just remove that.

Sure, will do.

BRs


> Thanks,
> Jeff
>
> > > > > ...or you could even make one that gives you the same format as the
> > > > > dirnames in /sys/kernel/debug/ceph.
> > > > >
> > > > > > diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c
> > > > > > index 6e061bf62ad4..a4b69c1026ce 100644
> > > > > > --- a/fs/ceph/ioctl.c
> > > > > > +++ b/fs/ceph/ioctl.c
> > > > > > @@ -268,6 +268,27 @@ static long ceph_ioctl_syncio(struct file *file)
> > > > > >     	return 0;
> > > > > >     }
> > > > > >     
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > +/*
> > > > > > + * Return the cluster and client ids
> > > > > > + */
> > > > > > +static long ceph_ioctl_get_fs_ids(struct file *file, void __user *arg)
> > > > > > +{
> > > > > > +	struct inode *inode = file_inode(file);
> > > > > > +	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
> > > > > > +	struct cluster_client_ids ids;
> > > > > > +
> > > > > > +	snprintf(ids.cluster_id, sizeof(ids.cluster_id), "%pU",
> > > > > > +		 &fsc->client->fsid);
> > > > > > +	snprintf(ids.client_id, sizeof(ids.client_id), "client%lld",
> > > > > > +		 ceph_client_gid(fsc->client));
> > > > > > +
> > > > > > +	/* send result back to user */
> > > > > > +	if (copy_to_user(arg, &ids, sizeof(ids)))
> > > > > > +		return -EFAULT;
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > >     long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> > > > > >     {
> > > > > >     	dout("ioctl file %p cmd %u arg %lu\n", file, cmd, arg);
> > > > > > @@ -289,6 +310,8 @@ long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> > > > > >     
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >     	case CEPH_IOC_SYNCIO:
> > > > > >     		return ceph_ioctl_syncio(file);
> > > > > > +	case CEPH_IOC_GET_CLUSTER_AND_CLIENT_IDS:
> > > > > > +		return ceph_ioctl_get_fs_ids(file, (void __user *)arg);
> > > > > >     	}
> > > > > >     
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >     	return -ENOTTY;
> > > > > > diff --git a/fs/ceph/ioctl.h b/fs/ceph/ioctl.h
> > > > > > index 51f7f1d39a94..9879d58854fb 100644
> > > > > > --- a/fs/ceph/ioctl.h
> > > > > > +++ b/fs/ceph/ioctl.h
> > > > > > @@ -98,4 +98,19 @@ struct ceph_ioctl_dataloc {
> > > > > >      */
> > > > > >     #define CEPH_IOC_SYNCIO _IO(CEPH_IOCTL_MAGIC, 5)
> > > > > >     
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > +/*
> > > > > > + * CEPH_IOC_GET_CLUSTER_AND_CLIENT_IDS - get the cluster and client ids
> > > > > > + *
> > > > > > + * This ioctl will return the cluster and client ids back to user space.
> > > > > > + * With this we can easily know which mountpoint the file belongs to and
> > > > > > + * also they can help locate the debugfs path quickly.
> > > > > > + */
> > > > > > +
> > > > > > +struct cluster_client_ids {
> > > > > > +	char cluster_id[40];
> > > > > > +	char client_id[24];
> > > > > > +};
> > > > > > +#define CEPH_IOC_GET_CLUSTER_AND_CLIENT_IDS _IOR(CEPH_IOCTL_MAGIC, 6, \
> > > > > > +					struct cluster_client_ids)
> > > > > > +
> > > > > >     #endif