Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (28 commits)
  ceph: update discussion list address in MAINTAINERS
  ceph: some documentations fixes
  ceph: fix use after free on mds __unregister_request
  ceph: avoid loaded term 'OSD' in documention
  ceph: fix possible double-free of mds request reference
  ceph: fix session check on mds reply
  ceph: handle kmalloc() failure
  ceph: propagate mds session allocation failures to caller
  ceph: make write_begin wait propagate ERESTARTSYS
  ceph: fix snap rebuild condition
  ceph: avoid reopening osd connections when address hasn't changed
  ceph: rename r_sent_stamp r_stamp
  ceph: fix connection fault con_work reentrancy problem
  ceph: prevent dup stale messages to console for restarting mds
  ceph: fix pg pool decoding from incremental osdmap update
  ceph: fix mds sync() race with completing requests
  ceph: only release unused caps with mds requests
  ceph: clean up handle_cap_grant, handle_caps wrt session mutex
  ceph: fix session locking in handle_caps, ceph_check_caps
  ceph: drop unnecessary WARN_ON in caps migration
  ...

1 files changed, 8 insertions, 2 deletions

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 23bb0ceabe31..ce8ef6107727 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -919,6 +919,10 @@ static int context_is_writeable_or_written(struct inode *inode,
 /*
  * We are only allowed to write into/dirty the page if the page is
  * clean, or already dirty within the same snap context.
+ *
+ * called with page locked.
+ * return success with page locked,
+ * or any failure (incl -EAGAIN) with page unlocked.
  */
 static int ceph_update_writeable_page(struct file *file,
                             loff_t pos, unsigned len,
@@ -961,9 +965,11 @@ retry_locked:
                         snapc = ceph_get_snap_context((void *)page->private);
                         unlock_page(page);
                         ceph_queue_writeback(inode);
-                        wait_event_interruptible(ci->i_cap_wq,
+                        r = wait_event_interruptible(ci->i_cap_wq,
                                context_is_writeable_or_written(inode, snapc));
                         ceph_put_snap_context(snapc);
+                        if (r == -ERESTARTSYS)
+                                return r;
                         return -EAGAIN;
                 }
 
@@ -1035,7 +1041,7 @@ static int ceph_write_begin(struct file *file, struct address_space *mapping,
         int r;
 
         do {
-                /* get a page*/
+                /* get a page */
                 page = grab_cache_page_write_begin(mapping, index, 0);
                 if (!page)
                         return -ENOMEM;