dm: refactor dm_suspend completion wait

Move completion wait to separate function

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 11f422ecfda000a6ee35ead97dbf8d4c0d433e08..9ca012e639a8dcf5bac68c50fe27ff73a12b1f0e 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1259,6 +1259,29 @@ void dm_put(struct mapped_device *md)
 }
 EXPORT_SYMBOL_GPL(dm_put);
 
+static int dm_wait_for_completion(struct mapped_device *md)
+{
+       int r = 0;
+
+       while (1) {
+               set_current_state(TASK_INTERRUPTIBLE);
+
+               smp_mb();
+               if (!atomic_read(&md->pending))
+                       break;
+
+               if (signal_pending(current)) {
+                       r = -EINTR;
+                       break;
+               }
+
+               io_schedule();
+       }
+       set_current_state(TASK_RUNNING);
+
+       return r;
+}
+
 /*
  * Process the deferred bios
  */
@@ -1357,7 +1380,7 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
 {
        struct dm_table *map = NULL;
        DECLARE_WAITQUEUE(wait, current);
-       int pending, r = 0;
+       int r = 0;
        int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0;
        int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0;
 
@@ -1414,20 +1437,9 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
                dm_table_unplug_all(map);
 
        /*
-        * Then we wait for the already mapped ios to
-        * complete.
+        * Wait for the already-mapped ios to complete.
         */
-       while (1) {
-               set_current_state(TASK_INTERRUPTIBLE);
-
-               smp_mb();
-               pending = atomic_read(&md->pending);
-               if (!pending || signal_pending(current))
-                       break;
-
-               io_schedule();
-       }
-       set_current_state(TASK_RUNNING);
+       r = dm_wait_for_completion(md);
 
        down_write(&md->io_lock);
        remove_wait_queue(&md->wait, &wait);
@@ -1437,13 +1449,12 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
        up_write(&md->io_lock);
 
        /* were we interrupted ? */
-       if (pending) {
+       if (r < 0) {
                down_write(&md->io_lock);
                __flush_deferred_io(md);
                up_write(&md->io_lock);
 
                unlock_fs(md);
-               r = -EINTR;
                goto out; /* pushback list is already flushed, so skip flush */
        }