ceph: use i_ceph_lock instead of i_lock

We have been using i_lock to protect all kinds of data structures in the
ceph_inode_info struct, including lists of inodes that we need to iterate
over while avoiding races with inode destruction.  That requires grabbing
a reference to the inode with the list lock protected, but igrab() now
takes i_lock to check the inode flags.

Changing the list lock ordering would be a painful process.

However, using a ceph-specific i_ceph_lock in the ceph inode instead of
i_lock is a simple mechanical change and avoids the ordering constraints
imposed by igrab().

Reported-by: Amon Ott <a.ott@m-privacy.de>
Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 94 insertions, 93 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 0f327c6..8b53193 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -309,7 +309,7 @@ void ceph_reservation_status(struct ceph_fs_client *fsc,
 /*
  * Find ceph_cap for given mds, if any.
  *
- * Called with i_lock held.
+ * Called with i_ceph_lock held.
  */
 static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 {
@@ -332,9 +332,9 @@ struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 {
 	struct ceph_cap *cap;
 
-	spin_lock(&ci->vfs_inode.i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	cap = __get_cap_for_mds(ci, mds);
-	spin_unlock(&ci->vfs_inode.i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	return cap;
 }
 
@@ -361,15 +361,16 @@ static int __ceph_get_cap_mds(struct ceph_inode_info *ci)
 
 int ceph_get_cap_mds(struct inode *inode)
 {
+	struct ceph_inode_info *ci = ceph_inode(inode);
 	int mds;
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	mds = __ceph_get_cap_mds(ceph_inode(inode));
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	return mds;
 }
 
 /*
- * Called under i_lock.
+ * Called under i_ceph_lock.
  */
 static void __insert_cap_node(struct ceph_inode_info *ci,
 			      struct ceph_cap *new)
@@ -415,7 +416,7 @@ static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
  *
  * If I_FLUSH is set, leave the inode at the front of the list.
  *
- * Caller holds i_lock
+ * Caller holds i_ceph_lock
  *    -> we take mdsc->cap_delay_lock
  */
 static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
@@ -457,7 +458,7 @@ static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
 /*
  * Cancel delayed work on cap.
  *
- * Caller must hold i_lock.
+ * Caller must hold i_ceph_lock.
  */
 static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
 			       struct ceph_inode_info *ci)
@@ -532,14 +533,14 @@ int ceph_add_cap(struct inode *inode,
 		wanted |= ceph_caps_for_mode(fmode);
 
 retry:
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	cap = __get_cap_for_mds(ci, mds);
 	if (!cap) {
 		if (new_cap) {
 			cap = new_cap;
 			new_cap = NULL;
 		} else {
-			spin_unlock(&inode->i_lock);
+			spin_unlock(&ci->i_ceph_lock);
 			new_cap = get_cap(mdsc, caps_reservation);
 			if (new_cap == NULL)
 				return -ENOMEM;
@@ -625,7 +626,7 @@ retry:
 
 	if (fmode >= 0)
 		__ceph_get_fmode(ci, fmode);
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	wake_up_all(&ci->i_cap_wq);
 	return 0;
 }
@@ -792,7 +793,7 @@ int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 	struct rb_node *p;
 	int ret = 0;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 		cap = rb_entry(p, struct ceph_cap, ci_node);
 		if (__cap_is_valid(cap) &&
@@ -801,7 +802,7 @@ int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 			break;
 		}
 	}
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	dout("ceph_caps_revoking %p %s = %d\n", inode,
 	     ceph_cap_string(mask), ret);
 	return ret;
@@ -855,7 +856,7 @@ int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
 }
 
 /*
- * called under i_lock
+ * called under i_ceph_lock
  */
 static int __ceph_is_any_caps(struct ceph_inode_info *ci)
 {
@@ -865,7 +866,7 @@ static int __ceph_is_any_caps(struct ceph_inode_info *ci)
 /*
  * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
  *
- * caller should hold i_lock.
+ * caller should hold i_ceph_lock.
  * caller will not hold session s_mutex if called from destroy_inode.
  */
 void __ceph_remove_cap(struct ceph_cap *cap)
@@ -1028,7 +1029,7 @@ static void __queue_cap_release(struct ceph_mds_session *session,
 
 /*
  * Queue cap releases when an inode is dropped from our cache.  Since
- * inode is about to be destroyed, there is no need for i_lock.
+ * inode is about to be destroyed, there is no need for i_ceph_lock.
  */
 void ceph_queue_caps_release(struct inode *inode)
 {
@@ -1049,7 +1050,7 @@ void ceph_queue_caps_release(struct inode *inode)
 
 /*
  * Send a cap msg on the given inode.  Update our caps state, then
- * drop i_lock and send the message.
+ * drop i_ceph_lock and send the message.
  *
  * Make note of max_size reported/requested from mds, revoked caps
  * that have now been implemented.
@@ -1061,13 +1062,13 @@ void ceph_queue_caps_release(struct inode *inode)
  * Return non-zero if delayed release, or we experienced an error
  * such that the caller should requeue + retry later.
  *
- * called with i_lock, then drops it.
+ * called with i_ceph_lock, then drops it.
  * caller should hold snap_rwsem (read), s_mutex.
  */
 static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
 		      int op, int used, int want, int retain, int flushing,
 		      unsigned *pflush_tid)
-	__releases(cap->ci->vfs_inode->i_lock)
+	__releases(cap->ci->i_ceph_lock)
 {
 	struct ceph_inode_info *ci = cap->ci;
 	struct inode *inode = &ci->vfs_inode;
@@ -1170,7 +1171,7 @@ static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
 		xattr_version = ci->i_xattrs.version;
 	}
 
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 
 	ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id,
 		op, keep, want, flushing, seq, flush_tid, issue_seq, mseq,
@@ -1198,13 +1199,13 @@ static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
  * Unless @again is true, skip cap_snaps that were already sent to
  * the MDS (i.e., during this session).
  *
- * Called under i_lock.  Takes s_mutex as needed.
+ * Called under i_ceph_lock.  Takes s_mutex as needed.
  */
 void __ceph_flush_snaps(struct ceph_inode_info *ci,
 			struct ceph_mds_session **psession,
 			int again)
-		__releases(ci->vfs_inode->i_lock)
-		__acquires(ci->vfs_inode->i_lock)
+		__releases(ci->i_ceph_lock)
+		__acquires(ci->i_ceph_lock)
 {
 	struct inode *inode = &ci->vfs_inode;
 	int mds;
@@ -1261,7 +1262,7 @@ retry:
 			session = NULL;
 		}
 		if (!session) {
-			spin_unlock(&inode->i_lock);
+			spin_unlock(&ci->i_ceph_lock);
 			mutex_lock(&mdsc->mutex);
 			session = __ceph_lookup_mds_session(mdsc, mds);
 			mutex_unlock(&mdsc->mutex);
@@ -1275,7 +1276,7 @@ retry:
 			 * deletion or migration.  retry, and we'll
 			 * get a better @mds value next time.
 			 */
-			spin_lock(&inode->i_lock);
+			spin_lock(&ci->i_ceph_lock);
 			goto retry;
 		}
 
@@ -1285,7 +1286,7 @@ retry:
 			list_del_init(&capsnap->flushing_item);
 		list_add_tail(&capsnap->flushing_item,
 			      &session->s_cap_snaps_flushing);
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&ci->i_ceph_lock);
 
 		dout("flush_snaps %p cap_snap %p follows %lld tid %llu\n",
 		     inode, capsnap, capsnap->follows, capsnap->flush_tid);
@@ -1302,7 +1303,7 @@ retry:
 		next_follows = capsnap->follows + 1;
 		ceph_put_cap_snap(capsnap);
 
-		spin_lock(&inode->i_lock);
+		spin_lock(&ci->i_ceph_lock);
 		goto retry;
 	}
 
@@ -1322,11 +1323,9 @@ out:
 
 static void ceph_flush_snaps(struct ceph_inode_info *ci)
 {
-	struct inode *inode = &ci->vfs_inode;
-
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	__ceph_flush_snaps(ci, NULL, 0);
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 }
 
 /*
@@ -1373,7 +1372,7 @@ int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
  * Add dirty inode to the flushing list.  Assigned a seq number so we
  * can wait for caps to flush without starving.
  *
- * Called under i_lock.
+ * Called under i_ceph_lock.
  */
 static int __mark_caps_flushing(struct inode *inode,
 				 struct ceph_mds_session *session)
@@ -1421,9 +1420,9 @@ static int try_nonblocking_invalidate(struct inode *inode)
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	u32 invalidating_gen = ci->i_rdcache_gen;
 
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	invalidate_mapping_pages(&inode->i_data, 0, -1);
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 
 	if (inode->i_data.nrpages == 0 &&
 	    invalidating_gen == ci->i_rdcache_gen) {
@@ -1470,7 +1469,7 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags,
 	if (mdsc->stopping)
 		is_delayed = 1;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 
 	if (ci->i_ceph_flags & CEPH_I_FLUSH)
 		flags |= CHECK_CAPS_FLUSH;
@@ -1480,7 +1479,7 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags,
 		__ceph_flush_snaps(ci, &session, 0);
 	goto retry_locked;
 retry:
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 retry_locked:
 	file_wanted = __ceph_caps_file_wanted(ci);
 	used = __ceph_caps_used(ci);
@@ -1634,7 +1633,7 @@ ack:
 			if (mutex_trylock(&session->s_mutex) == 0) {
 				dout("inverting session/ino locks on %p\n",
 				     session);
-				spin_unlock(&inode->i_lock);
+				spin_unlock(&ci->i_ceph_lock);
 				if (took_snap_rwsem) {
 					up_read(&mdsc->snap_rwsem);
 					took_snap_rwsem = 0;
@@ -1648,7 +1647,7 @@ ack:
 			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
 				dout("inverting snap/in locks on %p\n",
 				     inode);
-				spin_unlock(&inode->i_lock);
+				spin_unlock(&ci->i_ceph_lock);
 				down_read(&mdsc->snap_rwsem);
 				took_snap_rwsem = 1;
 				goto retry;
@@ -1664,10 +1663,10 @@ ack:
 		mds = cap->mds;  /* remember mds, so we don't repeat */
 		sent++;
 
-		/* __send_cap drops i_lock */
+		/* __send_cap drops i_ceph_lock */
 		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, used, want,
 				      retain, flushing, NULL);
-		goto retry; /* retake i_lock and restart our cap scan. */
+		goto retry; /* retake i_ceph_lock and restart our cap scan. */
 	}
 
 	/*
@@ -1681,7 +1680,7 @@ ack:
 	else if (!is_delayed || force_requeue)
 		__cap_delay_requeue(mdsc, ci);
 
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 
 	if (queue_invalidate)
 		ceph_queue_invalidate(inode);
@@ -1704,7 +1703,7 @@ static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session,
 	int flushing = 0;
 
 retry:
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
 		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
 		goto out;
@@ -1716,7 +1715,7 @@ retry:
 		int delayed;
 
 		if (!session) {
-			spin_unlock(&inode->i_lock);
+			spin_unlock(&ci->i_ceph_lock);
 			session = cap->session;
 			mutex_lock(&session->s_mutex);
 			goto retry;
@@ -1727,18 +1726,18 @@ retry:
 
 		flushing = __mark_caps_flushing(inode, session);
 
-		/* __send_cap drops i_lock */
+		/* __send_cap drops i_ceph_lock */
 		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want,
 				     cap->issued | cap->implemented, flushing,
 				     flush_tid);
 		if (!delayed)
 			goto out_unlocked;
 
-		spin_lock(&inode->i_lock);
+		spin_lock(&ci->i_ceph_lock);
 		__cap_delay_requeue(mdsc, ci);
 	}
 out:
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 out_unlocked:
 	if (session && unlock_session)
 		mutex_unlock(&session->s_mutex);
@@ -1753,7 +1752,7 @@ static int caps_are_flushed(struct inode *inode, unsigned tid)
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	int i, ret = 1;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	for (i = 0; i < CEPH_CAP_BITS; i++)
 		if ((ci->i_flushing_caps & (1 << i)) &&
 		    ci->i_cap_flush_tid[i] <= tid) {
@@ -1761,7 +1760,7 @@ static int caps_are_flushed(struct inode *inode, unsigned tid)
 			ret = 0;
 			break;
 		}
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	return ret;
 }
 
@@ -1868,10 +1867,10 @@ int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
 		struct ceph_mds_client *mdsc =
 			ceph_sb_to_client(inode->i_sb)->mdsc;
 
-		spin_lock(&inode->i_lock);
+		spin_lock(&ci->i_ceph_lock);
 		if (__ceph_caps_dirty(ci))
 			__cap_delay_requeue_front(mdsc, ci);
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&ci->i_ceph_lock);
 	}
 	return err;
 }
@@ -1894,7 +1893,7 @@ static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
 		struct inode *inode = &ci->vfs_inode;
 		struct ceph_cap *cap;
 
-		spin_lock(&inode->i_lock);
+		spin_lock(&ci->i_ceph_lock);
 		cap = ci->i_auth_cap;
 		if (cap && cap->session == session) {
 			dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
@@ -1904,7 +1903,7 @@ static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
 			pr_err("%p auth cap %p not mds%d ???\n", inode,
 			       cap, session->s_mds);
 		}
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&ci->i_ceph_lock);
 	}
 }
 
@@ -1921,7 +1920,7 @@ void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
 		struct ceph_cap *cap;
 		int delayed = 0;
 
-		spin_lock(&inode->i_lock);
+		spin_lock(&ci->i_ceph_lock);
 		cap = ci->i_auth_cap;
 		if (cap && cap->session == session) {
 			dout("kick_flushing_caps %p cap %p %s\n", inode,
@@ -1932,14 +1931,14 @@ void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
 					     cap->issued | cap->implemented,
 					     ci->i_flushing_caps, NULL);
 			if (delayed) {
-				spin_lock(&inode->i_lock);
+				spin_lock(&ci->i_ceph_lock);
 				__cap_delay_requeue(mdsc, ci);
-				spin_unlock(&inode->i_lock);
+				spin_unlock(&ci->i_ceph_lock);
 			}
 		} else {
 			pr_err("%p auth cap %p not mds%d ???\n", inode,
 			       cap, session->s_mds);
-			spin_unlock(&inode->i_lock);
+			spin_unlock(&ci->i_ceph_lock);
 		}
 	}
 }
@@ -1952,7 +1951,7 @@ static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
 	struct ceph_cap *cap;
 	int delayed = 0;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	cap = ci->i_auth_cap;
 	dout("kick_flushing_inode_caps %p flushing %s flush_seq %lld\n", inode,
 	     ceph_cap_string(ci->i_flushing_caps), ci->i_cap_flush_seq);
@@ -1964,12 +1963,12 @@ static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
 				     cap->issued | cap->implemented,
 				     ci->i_flushing_caps, NULL);
 		if (delayed) {
-			spin_lock(&inode->i_lock);
+			spin_lock(&ci->i_ceph_lock);
 			__cap_delay_requeue(mdsc, ci);
-			spin_unlock(&inode->i_lock);
+			spin_unlock(&ci->i_ceph_lock);
 		}
 	} else {
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&ci->i_ceph_lock);
 	}
 }
 
@@ -1978,7 +1977,7 @@ static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
  * Take references to capabilities we hold, so that we don't release
  * them to the MDS prematurely.
  *
- * Protected by i_lock.
+ * Protected by i_ceph_lock.
  */
 static void __take_cap_refs(struct ceph_inode_info *ci, int got)
 {
@@ -2016,7 +2015,7 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
 
 	dout("get_cap_refs %p need %s want %s\n", inode,
 	     ceph_cap_string(need), ceph_cap_string(want));
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 
 	/* make sure file is actually open */
 	file_wanted = __ceph_caps_file_wanted(ci);
@@ -2077,7 +2076,7 @@ static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
 		     ceph_cap_string(have), ceph_cap_string(need));
 	}
 out:
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	dout("get_cap_refs %p ret %d got %s\n", inode,
 	     ret, ceph_cap_string(*got));
 	return ret;
@@ -2094,7 +2093,7 @@ static void check_max_size(struct inode *inode, loff_t endoff)
 	int check = 0;
 
 	/* do we need to explicitly request a larger max_size? */
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	if ((endoff >= ci->i_max_size ||
 	     endoff > (inode->i_size << 1)) &&
 	    endoff > ci->i_wanted_max_size) {
@@ -2103,7 +2102,7 @@ static void check_max_size(struct inode *inode, loff_t endoff)
 		ci->i_wanted_max_size = endoff;
 		check = 1;
 	}
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	if (check)
 		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
 }
@@ -2140,9 +2139,9 @@ retry:
  */
 void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
 {
-	spin_lock(&ci->vfs_inode.i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	__take_cap_refs(ci, caps);
-	spin_unlock(&ci->vfs_inode.i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 }
 
 /*
@@ -2160,7 +2159,7 @@ void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
 	int last = 0, put = 0, flushsnaps = 0, wake = 0;
 	struct ceph_cap_snap *capsnap;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	if (had & CEPH_CAP_PIN)
 		--ci->i_pin_ref;
 	if (had & CEPH_CAP_FILE_RD)
@@ -2193,7 +2192,7 @@ void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
 				}
 			}
 		}
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 
 	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
 	     last ? " last" : "", put ? " put" : "");
@@ -2225,7 +2224,7 @@ void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
 	int found = 0;
 	struct ceph_cap_snap *capsnap = NULL;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	ci->i_wrbuffer_ref -= nr;
 	last = !ci->i_wrbuffer_ref;
 
@@ -2274,7 +2273,7 @@ void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
 		}
 	}
 
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 
 	if (last) {
 		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
@@ -2291,7 +2290,7 @@ void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
  * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
  * actually be a revocation if it specifies a smaller cap set.)
  *
- * caller holds s_mutex and i_lock, we drop both.
+ * caller holds s_mutex and i_ceph_lock, we drop both.
  *
  * return value:
  *  0 - ok
@@ -2302,7 +2301,7 @@ static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
 			     struct ceph_mds_session *session,
 			     struct ceph_cap *cap,
 			     struct ceph_buffer *xattr_buf)
-		__releases(inode->i_lock)
+		__releases(ci->i_ceph_lock)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	int mds = session->s_mds;
@@ -2453,7 +2452,7 @@ static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
 	}
 	BUG_ON(cap->issued & ~cap->implemented);
 
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	if (writeback)
 		/*
 		 * queue inode for writeback: we can't actually call
@@ -2483,7 +2482,7 @@ static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
 				 struct ceph_mds_caps *m,
 				 struct ceph_mds_session *session,
 				 struct ceph_cap *cap)
-	__releases(inode->i_lock)
+	__releases(ci->i_ceph_lock)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
@@ -2539,7 +2538,7 @@ static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
 	wake_up_all(&ci->i_cap_wq);
 
 out:
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	if (drop)
 		iput(inode);
 }
@@ -2562,7 +2561,7 @@ static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
 	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
 	     inode, ci, session->s_mds, follows);
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
 		if (capsnap->follows == follows) {
 			if (capsnap->flush_tid != flush_tid) {
@@ -2585,7 +2584,7 @@ static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
 			     capsnap, capsnap->follows);
 		}
 	}
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	if (drop)
 		iput(inode);
 }
@@ -2598,7 +2597,7 @@ static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
 static void handle_cap_trunc(struct inode *inode,
 			     struct ceph_mds_caps *trunc,
 			     struct ceph_mds_session *session)
-	__releases(inode->i_lock)
+	__releases(ci->i_ceph_lock)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	int mds = session->s_mds;
@@ -2617,7 +2616,7 @@ static void handle_cap_trunc(struct inode *inode,
 	     inode, mds, seq, truncate_size, truncate_seq);
 	queue_trunc = ceph_fill_file_size(inode, issued,
 					  truncate_seq, truncate_size, size);
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 
 	if (queue_trunc)
 		ceph_queue_vmtruncate(inode);
@@ -2646,7 +2645,7 @@ static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
 	dout("handle_cap_export inode %p ci %p mds%d mseq %d\n",
 	     inode, ci, mds, mseq);
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 
 	/* make sure we haven't seen a higher mseq */
 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
@@ -2690,7 +2689,7 @@ static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
 	}
 	/* else, we already released it */
 
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 }
 
 /*
@@ -2745,9 +2744,9 @@ static void handle_cap_import(struct ceph_mds_client *mdsc,
 	up_read(&mdsc->snap_rwsem);
 
 	/* make sure we re-request max_size, if necessary */
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	ci->i_requested_max_size = 0;
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 }
 
 /*
@@ -2762,6 +2761,7 @@ void ceph_handle_caps(struct ceph_mds_session *session,
 	struct ceph_mds_client *mdsc = session->s_mdsc;
 	struct super_block *sb = mdsc->fsc->sb;
 	struct inode *inode;
+	struct ceph_inode_info *ci;
 	struct ceph_cap *cap;
 	struct ceph_mds_caps *h;
 	int mds = session->s_mds;
@@ -2815,6 +2815,7 @@ void ceph_handle_caps(struct ceph_mds_session *session,
 
 	/* lookup ino */
 	inode = ceph_find_inode(sb, vino);
+	ci = ceph_inode(inode);
 	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
 	     vino.snap, inode);
 	if (!inode) {
@@ -2844,16 +2845,16 @@ void ceph_handle_caps(struct ceph_mds_session *session,
 	}
 
 	/* the rest require a cap */
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	cap = __get_cap_for_mds(ceph_inode(inode), mds);
 	if (!cap) {
 		dout(" no cap on %p ino %llx.%llx from mds%d\n",
 		     inode, ceph_ino(inode), ceph_snap(inode), mds);
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&ci->i_ceph_lock);
 		goto flush_cap_releases;
 	}
 
-	/* note that each of these drops i_lock for us */
+	/* note that each of these drops i_ceph_lock for us */
 	switch (op) {
 	case CEPH_CAP_OP_REVOKE:
 	case CEPH_CAP_OP_GRANT:
@@ -2869,7 +2870,7 @@ void ceph_handle_caps(struct ceph_mds_session *session,
 		break;
 
 	default:
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&ci->i_ceph_lock);
 		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
 		       ceph_cap_op_name(op));
 	}
@@ -2962,13 +2963,13 @@ void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
 	struct inode *inode = &ci->vfs_inode;
 	int last = 0;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
 	     ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
 	BUG_ON(ci->i_nr_by_mode[fmode] == 0);
 	if (--ci->i_nr_by_mode[fmode] == 0)
 		last++;
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 
 	if (last && ci->i_vino.snap == CEPH_NOSNAP)
 		ceph_check_caps(ci, 0, NULL);
@@ -2991,7 +2992,7 @@ int ceph_encode_inode_release(void **p, struct inode *inode,
 	int used, dirty;
 	int ret = 0;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&ci->i_ceph_lock);
 	used = __ceph_caps_used(ci);
 	dirty = __ceph_caps_dirty(ci);
 
@@ -3046,7 +3047,7 @@ int ceph_encode_inode_release(void **p, struct inode *inode,
 			     inode, cap, ceph_cap_string(cap->issued));
 		}
 	}
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&ci->i_ceph_lock);
 	return ret;
 }
 
@@ -3061,7 +3062,7 @@ int ceph_encode_dentry_release(void **p, struct dentry *dentry,
 
 	/*
 	 * force an record for the directory caps if we have a dentry lease.
-	 * this is racy (can't take i_lock and d_lock together), but it
+	 * this is racy (can't take i_ceph_lock and d_lock together), but it
 	 * doesn't have to be perfect; the mds will revoke anything we don't
 	 * release.
 	 */