]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - fs/ocfs2/journal.c
[PATCH] ocfs2: fix hang in dlm lock resource mastery
[linux-2.6-omap-h63xx.git] / fs / ocfs2 / journal.c
index d329c9df90ae8f19f03d03af7d8bd4036b22bf94..4be801f4559b5411261e4e23cac5836cd0c357e6 100644 (file)
@@ -1408,21 +1408,17 @@ bail:
        return status;
 }
 
-static int ocfs2_recover_orphans(struct ocfs2_super *osb,
-                                int slot)
+static int ocfs2_queue_orphans(struct ocfs2_super *osb,
+                              int slot,
+                              struct inode **head)
 {
-       int status = 0;
-       int have_disk_lock = 0;
-       struct inode *inode = NULL;
-       struct inode *iter;
+       int status;
        struct inode *orphan_dir_inode = NULL;
+       struct inode *iter;
        unsigned long offset, blk, local;
        struct buffer_head *bh = NULL;
        struct ocfs2_dir_entry *de;
        struct super_block *sb = osb->sb;
-       struct ocfs2_inode_info *oi;
-
-       mlog(0, "Recover inodes from orphan dir in slot %d\n", slot);
 
        orphan_dir_inode = ocfs2_get_system_file_inode(osb,
                                                       ORPHAN_DIR_SYSTEM_INODE,
@@ -1430,17 +1426,15 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
        if  (!orphan_dir_inode) {
                status = -ENOENT;
                mlog_errno(status);
-               goto out;
-       }
+               return status;
+       }       
 
        mutex_lock(&orphan_dir_inode->i_mutex);
        status = ocfs2_meta_lock(orphan_dir_inode, NULL, NULL, 0);
        if (status < 0) {
-               mutex_unlock(&orphan_dir_inode->i_mutex);
                mlog_errno(status);
                goto out;
        }
-       have_disk_lock = 1;
 
        offset = 0;
        iter = NULL;
@@ -1451,11 +1445,10 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
                if (!bh)
                        status = -EINVAL;
                if (status < 0) {
-                       mutex_unlock(&orphan_dir_inode->i_mutex);
                        if (bh)
                                brelse(bh);
                        mlog_errno(status);
-                       goto out;
+                       goto out_unlock;
                }
 
                local = 0;
@@ -1465,11 +1458,10 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
 
                        if (!ocfs2_check_dir_entry(orphan_dir_inode,
                                                  de, bh, local)) {
-                               mutex_unlock(&orphan_dir_inode->i_mutex);
                                status = -EINVAL;
                                mlog_errno(status);
                                brelse(bh);
-                               goto out;
+                               goto out_unlock;
                        }
 
                        local += le16_to_cpu(de->rec_len);
@@ -1504,18 +1496,95 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
 
                        mlog(0, "queue orphan %"MLFu64"\n",
                             OCFS2_I(iter)->ip_blkno);
-                       OCFS2_I(iter)->ip_next_orphan = inode;
-                       inode = iter;
+                       /* No locking is required for the next_orphan
+                        * queue as there is only ever a single
+                        * process doing orphan recovery. */
+                       OCFS2_I(iter)->ip_next_orphan = *head;
+                       *head = iter;
                }
                brelse(bh);
        }
-       mutex_unlock(&orphan_dir_inode->i_mutex);
 
+out_unlock:
        ocfs2_meta_unlock(orphan_dir_inode, 0);
-       have_disk_lock = 0;
-
+out:
+       mutex_unlock(&orphan_dir_inode->i_mutex);
        iput(orphan_dir_inode);
-       orphan_dir_inode = NULL;
+       return status;
+}
+
+static int ocfs2_orphan_recovery_can_continue(struct ocfs2_super *osb,
+                                             int slot)
+{
+       int ret;
+
+       spin_lock(&osb->osb_lock);
+       ret = !osb->osb_orphan_wipes[slot];
+       spin_unlock(&osb->osb_lock);
+       return ret;
+}
+
+static void ocfs2_mark_recovering_orphan_dir(struct ocfs2_super *osb,
+                                            int slot)
+{
+       spin_lock(&osb->osb_lock);
+       /* Mark ourselves such that new processes in delete_inode()
+        * know to quit early. */
+       ocfs2_node_map_set_bit(osb, &osb->osb_recovering_orphan_dirs, slot);
+       while (osb->osb_orphan_wipes[slot]) {
+               /* If any processes are already in the middle of an
+                * orphan wipe on this dir, then we need to wait for
+                * them. */
+               spin_unlock(&osb->osb_lock);
+               wait_event_interruptible(osb->osb_wipe_event,
+                                        ocfs2_orphan_recovery_can_continue(osb, slot));
+               spin_lock(&osb->osb_lock);
+       }
+       spin_unlock(&osb->osb_lock);
+}
+
+static void ocfs2_clear_recovering_orphan_dir(struct ocfs2_super *osb,
+                                             int slot)
+{
+       ocfs2_node_map_clear_bit(osb, &osb->osb_recovering_orphan_dirs, slot);
+}
+
+/*
+ * Orphan recovery. Each mounted node has it's own orphan dir which we
+ * must run during recovery. Our strategy here is to build a list of
+ * the inodes in the orphan dir and iget/iput them. The VFS does
+ * (most) of the rest of the work.
+ *
+ * Orphan recovery can happen at any time, not just mount so we have a
+ * couple of extra considerations.
+ *
+ * - We grab as many inodes as we can under the orphan dir lock -
+ *   doing iget() outside the orphan dir risks getting a reference on
+ *   an invalid inode.
+ * - We must be sure not to deadlock with other processes on the
+ *   system wanting to run delete_inode(). This can happen when they go
+ *   to lock the orphan dir and the orphan recovery process attempts to
+ *   iget() inside the orphan dir lock. This can be avoided by
+ *   advertising our state to ocfs2_delete_inode().
+ */
+static int ocfs2_recover_orphans(struct ocfs2_super *osb,
+                                int slot)
+{
+       int ret = 0;
+       struct inode *inode = NULL;
+       struct inode *iter;
+       struct ocfs2_inode_info *oi;
+
+       mlog(0, "Recover inodes from orphan dir in slot %d\n", slot);
+
+       ocfs2_mark_recovering_orphan_dir(osb, slot);
+       ret = ocfs2_queue_orphans(osb, slot, &inode);
+       ocfs2_clear_recovering_orphan_dir(osb, slot);
+
+       /* Error here should be noted, but we want to continue with as
+        * many queued inodes as we've got. */
+       if (ret)
+               mlog_errno(ret);
 
        while (inode) {
                oi = OCFS2_I(inode);
@@ -1541,14 +1610,7 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
                inode = iter;
        }
 
-out:
-       if (have_disk_lock)
-               ocfs2_meta_unlock(orphan_dir_inode, 0);
-
-       if (orphan_dir_inode)
-               iput(orphan_dir_inode);
-
-       return status;
+       return ret;
 }
 
 static int ocfs2_wait_on_mount(struct ocfs2_super *osb)