Commit b4c4c7b8 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

[PATCH] md: restart a (raid5) reshape that has been aborted due to a read/write error 



An error always aborts any resync/recovery/reshape on the understanding that
it will immediately be restarted if that still makes sense.  However a reshape
currently doesn't get restarted.  With this patch it does.

To avoid restarting when it is not possible to do work, we call into the
personality to check that a reshape is ok, and strengthen raid5_check_reshape
to fail if there are too many failed devices.

We also break some code out into a separate function: remove_and_add_spares as
the indent level for that code was getting crazy.

Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d1b5380c

drivers/md/md.c

+45 −29
Original line number Diff line number Diff line
@@ -5357,6 +5357,44 @@ void md_do_sync(mddev_t *mddev) 
EXPORT_SYMBOL_GPL(md_do_sync);





static int remove_and_add_spares(mddev_t *mddev)

{

	mdk_rdev_t *rdev;

	struct list_head *rtmp;

	int spares = 0;



	ITERATE_RDEV(mddev,rdev,rtmp)

		if (rdev->raid_disk >= 0 &&

		    (test_bit(Faulty, &rdev->flags) ||

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

		    atomic_read(&rdev->nr_pending)==0) {

			if (mddev->pers->hot_remove_disk(

				    mddev, rdev->raid_disk)==0) {

				char nm[20];

				sprintf(nm,"rd%d", rdev->raid_disk);

				sysfs_remove_link(&mddev->kobj, nm);

				rdev->raid_disk = -1;

			}

		}



	if (mddev->degraded) {

		ITERATE_RDEV(mddev,rdev,rtmp)

			if (rdev->raid_disk < 0

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

				rdev->recovery_offset = 0;

				if (mddev->pers->hot_add_disk(mddev,rdev)) {

					char nm[20];

					sprintf(nm, "rd%d", rdev->raid_disk);

					sysfs_create_link(&mddev->kobj,

							  &rdev->kobj, nm);

					spares++;

					md_new_event(mddev);

				} else

					break;

			}

	}

	return spares;

}

/*

 * This routine is regularly called by all per-raid-array threads to

 * deal with generic issues like resync and super-block update.
@@ -5474,35 +5512,13 @@ void md_check_recovery(mddev_t *mddev) 
		 * Spare are also removed and re-added, to allow

		 * the personality to fail the re-add.

		 */

		ITERATE_RDEV(mddev,rdev,rtmp)

			if (rdev->raid_disk >= 0 &&

			    (test_bit(Faulty, &rdev->flags) || ! test_bit(In_sync, &rdev->flags)) &&

			    atomic_read(&rdev->nr_pending)==0) {

				if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0) {

					char nm[20];

					sprintf(nm,"rd%d", rdev->raid_disk);

					sysfs_remove_link(&mddev->kobj, nm);

					rdev->raid_disk = -1;

				}

			}



		if (mddev->degraded) {

			ITERATE_RDEV(mddev,rdev,rtmp)

				if (rdev->raid_disk < 0

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

					rdev->recovery_offset = 0;

					if (mddev->pers->hot_add_disk(mddev,rdev)) {

						char nm[20];

						sprintf(nm, "rd%d", rdev->raid_disk);

						sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);

						spares++;

						md_new_event(mddev);

					} else

						break;

				}

		}



		if (spares) {

		if (mddev->reshape_position != MaxSector) {

			if (mddev->pers->check_reshape(mddev) != 0)

				/* Cannot proceed */

				goto unlock;

			set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);

		} else if ((spares = remove_and_add_spares(mddev))) {

			clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);

			clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);

		} else if (mddev->recovery_cp < MaxSector) {

drivers/md/raid5.c

+2 −0
Original line number Diff line number Diff line
@@ -3814,6 +3814,8 @@ static int raid5_check_reshape(mddev_t *mddev) 
	if (err)

		return err;



	if (mddev->degraded > conf->max_degraded)

		return -EINVAL;

	/* looks like we might be able to manage this */

	return 0;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE