Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvar...

[pandora-kernel.git] / fs / dlm / plock.c

diff --git a/fs/dlm/plock.c b/fs/dlm/plock.c
index 30d8b85..e2b8780 100644 (file)
--- a/fs/dlm/plock.c
+++ b/fs/dlm/plock.c
@@ -71,6 +71,36 @@ static void send_op(struct plock_op *op)
        wake_up(&send_wq);
 }
 
+/* If a process was killed while waiting for the only plock on a file,
+   locks_remove_posix will not see any lock on the file so it won't
+   send an unlock-close to us to pass on to userspace to clean up the
+   abandoned waiter.  So, we have to insert the unlock-close when the
+   lock call is interrupted. */
+
+static void do_unlock_close(struct dlm_ls *ls, u64 number,
+                           struct file *file, struct file_lock *fl)
+{
+       struct plock_op *op;
+
+       op = kzalloc(sizeof(*op), GFP_NOFS);
+       if (!op)
+               return;
+
+       op->info.optype         = DLM_PLOCK_OP_UNLOCK;
+       op->info.pid            = fl->fl_pid;
+       op->info.fsid           = ls->ls_global_id;
+       op->info.number         = number;
+       op->info.start          = 0;
+       op->info.end            = OFFSET_MAX;
+       if (fl->fl_lmops && fl->fl_lmops->fl_grant)
+               op->info.owner  = (__u64) fl->fl_pid;
+       else
+               op->info.owner  = (__u64)(long) fl->fl_owner;
+
+       op->info.flags |= DLM_PLOCK_FL_CLOSE;
+       send_op(op);
+}
+
 int dlm_posix_lock(dlm_lockspace_t *lockspace, u64 number, struct file *file,
                   int cmd, struct file_lock *fl)
 {
@@ -114,9 +144,19 @@ int dlm_posix_lock(dlm_lockspace_t *lockspace, u64 number, struct file *file,
 
        send_op(op);
 
-       if (xop->callback == NULL)
-               wait_event(recv_wq, (op->done != 0));
-       else {
+       if (xop->callback == NULL) {
+               rv = wait_event_killable(recv_wq, (op->done != 0));
+               if (rv == -ERESTARTSYS) {
+                       log_debug(ls, "dlm_posix_lock: wait killed %llx",
+                                 (unsigned long long)number);
+                       spin_lock(&ops_lock);
+                       list_del(&op->list);
+                       spin_unlock(&ops_lock);
+                       kfree(xop);
+                       do_unlock_close(ls, number, file, fl);
+                       goto out;
+               }
+       } else {
                rv = FILE_LOCK_DEFERRED;
                goto out;
        }
@@ -233,6 +273,13 @@ int dlm_posix_unlock(dlm_lockspace_t *lockspace, u64 number, struct file *file,
        else
                op->info.owner  = (__u64)(long) fl->fl_owner;
 
+       if (fl->fl_flags & FL_CLOSE) {
+               op->info.flags |= DLM_PLOCK_FL_CLOSE;
+               send_op(op);
+               rv = 0;
+               goto out;
+       }
+
        send_op(op);
        wait_event(recv_wq, (op->done != 0));
 
@@ -334,7 +381,10 @@ static ssize_t dev_read(struct file *file, char __user *u, size_t count,
        spin_lock(&ops_lock);
        if (!list_empty(&send_list)) {
                op = list_entry(send_list.next, struct plock_op, list);
-               list_move(&op->list, &recv_list);
+               if (op->info.flags & DLM_PLOCK_FL_CLOSE)
+                       list_del(&op->list);
+               else
+                       list_move(&op->list, &recv_list);
                memcpy(&info, &op->info, sizeof(info));
        }
        spin_unlock(&ops_lock);
@@ -342,6 +392,13 @@ static ssize_t dev_read(struct file *file, char __user *u, size_t count,
        if (!op)
                return -EAGAIN;
 
+       /* there is no need to get a reply from userspace for unlocks
+          that were generated by the vfs cleaning up for a close
+          (the process did not make an unlock call). */
+
+       if (op->info.flags & DLM_PLOCK_FL_CLOSE)
+               kfree(op);
+
        if (copy_to_user(u, &info, sizeof(info)))
                return -EFAULT;
        return sizeof(info);