X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=fs%2Fblock_dev.c;h=c7bda5cd3da74daa998d1fda16c3e78240d7e872;hb=868f6fea8fa63f09acbfa93256d0d2abdcabff79;hp=bb43ce081d6ecef40b552d27f2b846a0d1a7606c;hpb=7644a448ccf200d95ad4426e84a486dec5cc1703;p=~andy%2Flinux

diff --git a/fs/block_dev.c b/fs/block_dev.c
index bb43ce081d6..c7bda5cd3da 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -58,17 +58,24 @@ static void bdev_inode_switch_bdi(struct inode *inode,
 			struct backing_dev_info *dst)
 {
 	struct backing_dev_info *old = inode->i_data.backing_dev_info;
+	bool wakeup_bdi = false;
 
 	if (unlikely(dst == old))		/* deadlock avoidance */
 		return;
 	bdi_lock_two(&old->wb, &dst->wb);
 	spin_lock(&inode->i_lock);
 	inode->i_data.backing_dev_info = dst;
-	if (inode->i_state & I_DIRTY)
+	if (inode->i_state & I_DIRTY) {
+		if (bdi_cap_writeback_dirty(dst) && !wb_has_dirty_io(&dst->wb))
+			wakeup_bdi = true;
 		list_move(&inode->i_wb_list, &dst->wb.b_dirty);
+	}
 	spin_unlock(&inode->i_lock);
 	spin_unlock(&old->wb.list_lock);
 	spin_unlock(&dst->wb.list_lock);
+
+	if (wakeup_bdi)
+		bdi_wakeup_thread_delayed(dst);
 }
 
 /* Kill _all_ buffers and pagecache , dirty or not.. */