Commit 72a8d129 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-linus' of git://neil.brown.name/md 

* 'for-linus' of git://neil.brown.name/md:
  Fix problem with waiting while holding rcu read lock in md/bitmap.c
  Remove invalidate_partition call from do_md_stop.
parents 7ed77e80 b2d2c4ce

drivers/md/bitmap.c

+38 −7
Original line number Diff line number Diff line
@@ -238,15 +238,47 @@ static struct page *read_sb_page(mddev_t *mddev, long offset, unsigned long inde 


}



static mdk_rdev_t *next_active_rdev(mdk_rdev_t *rdev, mddev_t *mddev)

{

	/* Iterate the disks of an mddev, using rcu to protect access to the

	 * linked list, and raising the refcount of devices we return to ensure

	 * they don't disappear while in use.

	 * As devices are only added or removed when raid_disk is < 0 and

	 * nr_pending is 0 and In_sync is clear, the entries we return will

	 * still be in the same position on the list when we re-enter

	 * list_for_each_continue_rcu.

	 */

	struct list_head *pos;

	rcu_read_lock();

	if (rdev == NULL)

		/* start at the beginning */

		pos = &mddev->disks;

	else {

		/* release the previous rdev and start from there. */

		rdev_dec_pending(rdev, mddev);

		pos = &rdev->same_set;

	}

	list_for_each_continue_rcu(pos, &mddev->disks) {

		rdev = list_entry(pos, mdk_rdev_t, same_set);

		if (rdev->raid_disk >= 0 &&

		    test_bit(In_sync, &rdev->flags) &&

		    !test_bit(Faulty, &rdev->flags)) {

			/* this is a usable devices */

			atomic_inc(&rdev->nr_pending);

			rcu_read_unlock();

			return rdev;

		}

	}

	rcu_read_unlock();

	return NULL;

}



static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)

{

	mdk_rdev_t *rdev;

	mdk_rdev_t *rdev = NULL;

	mddev_t *mddev = bitmap->mddev;



	rcu_read_lock();

	rdev_for_each_rcu(rdev, mddev)

		if (test_bit(In_sync, &rdev->flags)

		    && !test_bit(Faulty, &rdev->flags)) {

	while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {

			int size = PAGE_SIZE;

			if (page->index == bitmap->file_pages-1)

				size = roundup(bitmap->last_page_size,
@@ -282,7 +314,6 @@ static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait) 
				       size,

				       page);

	}

	rcu_read_unlock();



	if (wait)

		md_super_wait(mddev);

drivers/md/md.c

+0 −2
Original line number Diff line number Diff line
@@ -3841,8 +3841,6 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open) 


		del_timer_sync(&mddev->safemode_timer);



		invalidate_partition(disk, 0);



		switch(mode) {

		case 1: /* readonly */

			err  = -ENXIO;