X-Git-Url: http://git.agner.ch/gitweb/?a=blobdiff_plain;f=fs%2Fbtrfs%2Fdisk-io.c;h=a9aadb2ad5254cfe98d36a6eed1f12d4ae5e7925;hb=31b7a57c9eb3d90c87b6c2b855720ec709d2f6be;hp=b59deb2c63f4e2fe6cfb83cbbada6e4a45f8f002;hpb=67c5e7d464bc466471b05e027abe8a6b29687ebd;p=linux-drm-fsl-dcu.git

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b59deb2c63f4..a9aadb2ad525 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1744,13 +1744,14 @@ static void end_workqueue_fn(struct btrfs_work *work)
 	bio->bi_private = end_io_wq->private;
 	bio->bi_end_io = end_io_wq->end_io;
 	kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
-	bio_endio_nodec(bio, error);
+	bio_endio(bio, error);
 }
 
 static int cleaner_kthread(void *arg)
 {
 	struct btrfs_root *root = arg;
 	int again;
+	struct btrfs_trans_handle *trans;
 
 	do {
 		again = 0;
@@ -1798,6 +1799,34 @@ sleep:
 			__set_current_state(TASK_RUNNING);
 		}
 	} while (!kthread_should_stop());
+
+	/*
+	 * Transaction kthread is stopped before us and wakes us up.
+	 * However we might have started a new transaction and COWed some
+	 * tree blocks when deleting unused block groups for example. So
+	 * make sure we commit the transaction we started to have a clean
+	 * shutdown when evicting the btree inode - if it has dirty pages
+	 * when we do the final iput() on it, eviction will trigger a
+	 * writeback for it which will fail with null pointer dereferences
+	 * since work queues and other resources were already released and
+	 * destroyed by the time the iput/eviction/writeback is made.
+	 */
+	trans = btrfs_attach_transaction(root);
+	if (IS_ERR(trans)) {
+		if (PTR_ERR(trans) != -ENOENT)
+			btrfs_err(root->fs_info,
+				  "cleaner transaction attach returned %ld",
+				  PTR_ERR(trans));
+	} else {
+		int ret;
+
+		ret = btrfs_commit_transaction(trans, root);
+		if (ret)
+			btrfs_err(root->fs_info,
+				  "cleaner open transaction commit returned %d",
+				  ret);
+	}
+
 	return 0;
 }
 
@@ -3296,11 +3325,8 @@ static int write_dev_supers(struct btrfs_device *device,
  */
 static void btrfs_end_empty_barrier(struct bio *bio, int err)
 {
-	if (err) {
-		if (err == -EOPNOTSUPP)
-			set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
+	if (err)
 		clear_bit(BIO_UPTODATE, &bio->bi_flags);
-	}
 	if (bio->bi_private)
 		complete(bio->bi_private);
 	bio_put(bio);
@@ -3328,11 +3354,7 @@ static int write_dev_flush(struct btrfs_device *device, int wait)
 
 		wait_for_completion(&device->flush_wait);
 
-		if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
-			printk_in_rcu("BTRFS: disabling barriers on dev %s\n",
-				      rcu_str_deref(device->name));
-			device->nobarriers = 1;
-		} else if (!bio_flagged(bio, BIO_UPTODATE)) {
+		if (!bio_flagged(bio, BIO_UPTODATE)) {
 			ret = -EIO;
 			btrfs_dev_stat_inc_and_print(device,
 				BTRFS_DEV_STAT_FLUSH_ERRS);