Commit 6eef4b21 authored by NeilBrown's avatar NeilBrown
Browse files

md: add honouring of suspend_{lo,hi} to raid1. 



This will allow us to stop writeout to portions of the array
while  they are resynced by someone else - e.g. another node in
a cluster.

Signed-off-by: default avatarNeilBrown <neilb@suse.de>
parent 729a1866

drivers/md/raid1.c

+22 −0
Original line number Diff line number Diff line
@@ -801,6 +801,25 @@ static int make_request(struct request_queue *q, struct bio * bio) 


	md_write_start(mddev, bio); /* wait on superblock update early */



	if (bio_data_dir(bio) == WRITE &&

	    bio->bi_sector + bio->bi_size/512 > mddev->suspend_lo &&

	    bio->bi_sector < mddev->suspend_hi) {

		/* As the suspend_* range is controlled by

		 * userspace, we want an interruptible

		 * wait.

		 */

		DEFINE_WAIT(w);

		for (;;) {

			flush_signals(current);

			prepare_to_wait(&conf->wait_barrier,

					&w, TASK_INTERRUPTIBLE);

			if (bio->bi_sector + bio->bi_size/512 <= mddev->suspend_lo ||

			    bio->bi_sector >= mddev->suspend_hi)

				break;

			schedule();

		}

		finish_wait(&conf->wait_barrier, &w);

	}

	if (unlikely(!mddev->barriers_work &&

		     bio_rw_flagged(bio, BIO_RW_BARRIER))) {

		if (rw == WRITE)
@@ -2271,6 +2290,9 @@ static void raid1_quiesce(mddev_t *mddev, int state) 
	conf_t *conf = mddev->private;



	switch(state) {

	case 2: /* wake for suspend */

		wake_up(&conf->wait_barrier);

		break;

	case 1:

		raise_barrier(conf);

		break;