libceph: add ceph_monc_wait_osdmap()

Add ceph_monc_wait_osdmap(), which will block until the osdmap with the
specified epoch is received or timeout occurs.

Export both of these as they are going to be needed by rbd.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

diff --git a/include/linux/ceph/mon_client.h b/include/linux/ceph/mon_client.h
index 585ef9450e9d21258192880c80ae47fda3960bfa..deb47e45ac7c29b11642842a733a351f05bedbb3 100644 (file)
--- a/include/linux/ceph/mon_client.h
+++ b/include/linux/ceph/mon_client.h
@@ -104,6 +104,8 @@ extern int ceph_monc_got_mdsmap(struct ceph_mon_client *monc, u32 have);
 extern int ceph_monc_got_osdmap(struct ceph_mon_client *monc, u32 have);
 
 extern void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc);
+extern int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
+                                unsigned long timeout);
 
 extern int ceph_monc_do_statfs(struct ceph_mon_client *monc,
                               struct ceph_statfs *buf);

diff --git a/net/ceph/mon_client.c b/net/ceph/mon_client.c
index 11d8d2f2708ac2abbcf9661e80434a3eebc350d8..067d3af2eaf61be41d601dc4324fc1a1565ab27d 100644 (file)
--- a/net/ceph/mon_client.c
+++ b/net/ceph/mon_client.c
@@ -296,6 +296,33 @@ void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc)
                __send_subscribe(monc);
        mutex_unlock(&monc->mutex);
 }
+EXPORT_SYMBOL(ceph_monc_request_next_osdmap);
+
+int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
+                         unsigned long timeout)
+{
+       unsigned long started = jiffies;
+       int ret;
+
+       mutex_lock(&monc->mutex);
+       while (monc->have_osdmap < epoch) {
+               mutex_unlock(&monc->mutex);
+
+               if (timeout != 0 && time_after_eq(jiffies, started + timeout))
+                       return -ETIMEDOUT;
+
+               ret = wait_event_interruptible_timeout(monc->client->auth_wq,
+                                        monc->have_osdmap >= epoch, timeout);
+               if (ret < 0)
+                       return ret;
+
+               mutex_lock(&monc->mutex);
+       }
+
+       mutex_unlock(&monc->mutex);
+       return 0;
+}
+EXPORT_SYMBOL(ceph_monc_wait_osdmap);
 
 /*
  *