kclient: fix snap_realm leak

Separate lookup/create from get (this is safe because we always
hold span_rwsem during these operations).

diff --git a/src/kernel/caps.c b/src/kernel/caps.c
index a89f2c9abba7d7ec9676f76ce25d90659c47e5c9..7b796df14ad35b1d399b6f24c00af652990fb1ad 100644 (file)
--- a/src/kernel/caps.c
+++ b/src/kernel/caps.c
@@ -273,9 +273,10 @@ retry:
        __adjust_cap_rdcaps_listing(ci, cap, __ceph_caps_wanted(ci) | wanted);
 
        if (!ci->i_snap_realm) {
-               struct ceph_snap_realm *realm = ceph_get_snap_realm(mdsc,
-                                                                   realmino);
+               struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
+                                                              realmino);
                if (realm) {
+                       ceph_get_snap_realm(mdsc, realm);
                        ci->i_snap_realm = realm;
                        list_add(&ci->i_snap_realm_item, &realm->inodes_with_caps);
                } else {

diff --git a/src/kernel/snap.c b/src/kernel/snap.c
index 0137ecc167189d0951a16127f97a28f0321cd94d..f034b1ff72251a971dcba2706b63a28222e2c52d 100644 (file)
--- a/src/kernel/snap.c
+++ b/src/kernel/snap.c
@@ -62,9 +62,11 @@ int ceph_debug_snap __read_mostly = -1;
  *
  * caller must hold snap_rwsem for write.
  */
-static void get_realm(struct ceph_mds_client *mdsc,
-                     struct ceph_snap_realm *realm)
+void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
+                        struct ceph_snap_realm *realm)
 {
+       dout(20, "get_realm %p %d -> %d\n", realm,
+            atomic_read(&realm->nref), atomic_read(&realm->nref)+1);
        /*
         * since we _only_ increment realm refs or empty the empty
         * list with snap_rwsem held, adjusting the empty list here is
@@ -111,17 +113,14 @@ static struct ceph_snap_realm *ceph_create_snap_realm(struct ceph_mds_client *md
  *
  * caller must hold snap_rwsem for write.
  */
-struct ceph_snap_realm *ceph_get_snap_realm(struct ceph_mds_client *mdsc,
-                                           u64 ino)
+struct ceph_snap_realm *ceph_lookup_snap_realm(struct ceph_mds_client *mdsc,
+                                              u64 ino)
 {
        struct ceph_snap_realm *realm;
 
        realm = radix_tree_lookup(&mdsc->snap_realms, ino);
-       if (realm) {
-               dout(20, "get_snap_realm %llx %p %d -> %d\n", realm->ino, realm,
-                    atomic_read(&realm->nref), atomic_read(&realm->nref)+1);
-               get_realm(mdsc, realm);
-       }
+       if (realm)
+               dout(20, "lookup_snap_realm %llx %p\n", realm->ino, realm);
        return realm;
 }
 
@@ -229,7 +228,7 @@ static int adjust_snap_realm_parent(struct ceph_mds_client *mdsc,
        if (realm->parent_ino == parentino)
                return 0;
 
-       parent = ceph_get_snap_realm(mdsc, parentino);
+       parent = ceph_lookup_snap_realm(mdsc, parentino);
        if (IS_ERR(parent))
                return PTR_ERR(parent);
        if (!parent) {
@@ -246,7 +245,7 @@ static int adjust_snap_realm_parent(struct ceph_mds_client *mdsc,
        }
        realm->parent_ino = parentino;
        realm->parent = parent;
-       get_realm(mdsc, parent);
+       ceph_get_snap_realm(mdsc, parent);
        list_add(&realm->child_item, &parent->children);
        return 1;
 }
@@ -540,7 +539,7 @@ more:
        prior_parent_snaps = p;
        p += sizeof(u64) * le32_to_cpu(ri->num_prior_parent_snaps);
 
-       realm = ceph_get_snap_realm(mdsc, le64_to_cpu(ri->ino));
+       realm = ceph_lookup_snap_realm(mdsc, le64_to_cpu(ri->ino));
        if (IS_ERR(realm)) {
                err = PTR_ERR(realm);
                goto fail;
@@ -613,15 +612,14 @@ more:
        dout(10, "done with %llx %p, invalidated=%d, %p %p\n", realm->ino,
             realm, invalidate, p, e);
 
-       /* invalidate when we reach the _end_ (root) of the trace */
-       if (p == e && invalidate)
-               rebuild_snap_realms(realm);
-
        if (p < e)
                goto more;
 
-       __cleanup_empty_realms(mdsc);
+       /* invalidate when we reach the _end_ (root) of the trace */
+       if (invalidate)
+               rebuild_snap_realms(realm);
 
+       __cleanup_empty_realms(mdsc);
        return 0;
 
 bad:
@@ -751,15 +749,15 @@ void ceph_handle_snap(struct ceph_mds_client *mdsc,
                 * ceph_update_snap_trace. */
                ri = p;
 
-               realm = ceph_get_snap_realm(mdsc, split);
+               realm = ceph_lookup_snap_realm(mdsc, split);
                if (IS_ERR(realm))
                        goto out;
                if (!realm) {
                        realm = ceph_create_snap_realm(mdsc, split);
                        if (IS_ERR(realm))
                                goto out;
-                       get_realm(mdsc, realm);
                }
+               ceph_get_snap_realm(mdsc, realm);
 
                dout(10, "splitting snap_realm %llx %p\n", realm->ino, realm);
                for (i = 0; i < num_split_inos; i++) {
@@ -817,14 +815,13 @@ void ceph_handle_snap(struct ceph_mds_client *mdsc,
                /* we may have taken some of the old realm's children. */
                for (i = 0; i < num_split_realms; i++) {
                        struct ceph_snap_realm *child =
-                               ceph_get_snap_realm(mdsc,
+                               ceph_lookup_snap_realm(mdsc,
                                           le64_to_cpu(split_realms[i]));
                        if (IS_ERR(child))
                                continue;
                        if (!child)
                                continue;
                        adjust_snap_realm_parent(mdsc, child, realm->ino);
-                       ceph_put_snap_realm(mdsc, child);
                }
        }
 
@@ -857,7 +854,7 @@ void ceph_handle_snap(struct ceph_mds_client *mdsc,
                        list_add(&ci->i_snap_realm_item,
                                 &realm->inodes_with_caps);
                        ci->i_snap_realm = realm;
-                       get_realm(mdsc, realm);
+                       ceph_get_snap_realm(mdsc, realm);
                split_skip_inode:
                        spin_unlock(&inode->i_lock);
                        iput(inode);

diff --git a/src/kernel/super.h b/src/kernel/super.h
index b8b36dde2866cb47a1808b5b8c3c986866086a98..f0a554dca6a06b09d21be74d153d3276a2f8cc79 100644 (file)
--- a/src/kernel/super.h
+++ b/src/kernel/super.h
@@ -620,8 +620,10 @@ static inline int calc_pages_for(u64 off, u64 len)
 
 
 /* snap.c */
-struct ceph_snap_realm *ceph_get_snap_realm(struct ceph_mds_client *mdsc,
-                                           u64 ino);
+struct ceph_snap_realm *ceph_lookup_snap_realm(struct ceph_mds_client *mdsc,
+                                              u64 ino);
+extern void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
+                               struct ceph_snap_realm *realm);
 extern void ceph_put_snap_realm(struct ceph_mds_client *mdsc,
                                struct ceph_snap_realm *realm);
 extern int ceph_update_snap_trace(struct ceph_mds_client *m,