thp: fix page_referenced to modify mapcount/vm_flags only if page is found

[mv-sheeva.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 5e23152d04ad02b8c871beb230e95389a5c79c90..889287019599a861d90a51d6808cfb2d032fc255 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -873,6 +873,11 @@ int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk)
        ret = add_symlink(bdev->bd_part->holder_dir, &disk_to_dev(disk)->kobj);
        if (ret)
                goto out_del;
+       /*
+        * bdev could be deleted beneath us which would implicitly destroy
+        * the holder directory.  Hold on to it.
+        */
+       kobject_get(bdev->bd_part->holder_dir);
 
        list_add(&holder->list, &bdev->bd_holder_disks);
        goto out_unlock;
@@ -909,6 +914,7 @@ void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk)
                del_symlink(disk->slave_dir, &part_to_dev(bdev->bd_part)->kobj);
                del_symlink(bdev->bd_part->holder_dir,
                            &disk_to_dev(disk)->kobj);
+               kobject_put(bdev->bd_part->holder_dir);
                list_del_init(&holder->list);
                kfree(holder);
        }
@@ -922,6 +928,7 @@ EXPORT_SYMBOL_GPL(bd_unlink_disk_holder);
  * flush_disk - invalidates all buffer-cache entries on a disk
  *
  * @bdev:      struct block device to be flushed
+ * @kill_dirty: flag to guide handling of dirty inodes
  *
  * Invalidates all buffer-cache entries on a disk. It should be called
  * when a disk has been changed -- either by a media change or online
@@ -1215,12 +1222,6 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder)
 
        res = __blkdev_get(bdev, mode, 0);
 
-       /* __blkdev_get() may alter read only status, check it afterwards */
-       if (!res && (mode & FMODE_WRITE) && bdev_read_only(bdev)) {
-               __blkdev_put(bdev, mode, 0);
-               res = -EACCES;
-       }
-
        if (whole) {
                /* finish claiming */
                mutex_lock(&bdev->bd_mutex);
@@ -1298,6 +1299,11 @@ struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
        if (err)
                return ERR_PTR(err);
 
+       if ((mode & FMODE_WRITE) && bdev_read_only(bdev)) {
+               blkdev_put(bdev, mode);
+               return ERR_PTR(-EACCES);
+       }
+
        return bdev;
 }
 EXPORT_SYMBOL(blkdev_get_by_path);