[DLM] fix leaking user locks

User NOQUEUE lock requests to a remote node that failed with -EAGAIN were
never being removed from a process's list of locks.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

2 files changed, 20 insertions, 3 deletions

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 82e1ac25184..22744321816 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -526,6 +526,7 @@ static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
         lkb->lkb_nodeid = -1;
         lkb->lkb_grmode = DLM_LOCK_IV;
         kref_init(&lkb->lkb_ref);
+        INIT_LIST_HEAD(&lkb->lkb_ownqueue);
 
         get_random_bytes(&bucket, sizeof(bucket));
         bucket &= (ls->ls_lkbtbl_size - 1);
@@ -3705,7 +3706,7 @@ int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
                 goto out_put;
 
         spin_lock(&ua->proc->locks_spin);
-        list_del(&lkb->lkb_ownqueue);
+        list_del_init(&lkb->lkb_ownqueue);
         spin_unlock(&ua->proc->locks_spin);
 
         /* this removes the reference for the proc->locks list added by
@@ -3749,7 +3750,7 @@ int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
         /* this lkb was removed from the WAITING queue */
         if (lkb->lkb_grmode == DLM_LOCK_IV) {
                 spin_lock(&ua->proc->locks_spin);
-                list_del(&lkb->lkb_ownqueue);
+                list_del_init(&lkb->lkb_ownqueue);
                 spin_unlock(&ua->proc->locks_spin);
                 unhold_lkb(lkb);
         }
@@ -3817,7 +3818,7 @@ void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
                         unhold_lkb(lkb);
                 }
 
-                list_del(&lkb->lkb_ownqueue);
+                list_del_init(&lkb->lkb_ownqueue);
 
                 if (lkb->lkb_exflags & DLM_LKF_PERSISTENT) {
                         lkb->lkb_flags |= DLM_IFL_ORPHAN;
diff --git a/fs/dlm/user.c b/fs/dlm/user.c
index 1f05960a916..fd19caf9af9 100644
--- a/fs/dlm/user.c
+++ b/fs/dlm/user.c
@@ -133,6 +133,7 @@ void dlm_user_add_ast(struct dlm_lkb *lkb, int type)
         struct dlm_ls *ls;
         struct dlm_user_args *ua;
         struct dlm_user_proc *proc;
+        int remove_ownqueue = 0;
 
         /* dlm_clear_proc_locks() sets ORPHAN/DEAD flag on each
            lkb before dealing with it.  We need to check this
@@ -171,6 +172,14 @@ void dlm_user_add_ast(struct dlm_lkb *lkb, int type)
                 wake_up_interruptible(&proc->wait);
         }
 
+        /* noqueue requests that fail may need to be removed from the
+           proc's locks list, there should be a better way of detecting
+           this situation than checking all these things... */
+           
+        if (type == AST_COMP && lkb->lkb_grmode == DLM_LOCK_IV &&
+            ua->lksb.sb_status == -EAGAIN && !list_empty(&lkb->lkb_ownqueue))
+                remove_ownqueue = 1;
+
         /* We want to copy the lvb to userspace when the completion
            ast is read if the status is 0, the lock has an lvb and
            lvb_ops says we should.  We could probably have set_lvb_lock()
@@ -185,6 +194,13 @@ void dlm_user_add_ast(struct dlm_lkb *lkb, int type)
                 ua->update_user_lvb = 0;
 
         spin_unlock(&proc->asts_spin);
+
+        if (remove_ownqueue) {
+                spin_lock(&ua->proc->locks_spin);
+                list_del_init(&lkb->lkb_ownqueue);
+                spin_unlock(&ua->proc->locks_spin);
+                dlm_put_lkb(lkb);
+        }
  out:
         mutex_unlock(&ls->ls_clear_proc_locks);
 }