Commit 24dd469d authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

[PATCH] md: allow a manual resync with md 



You can trigger a 'check' with
  echo check > /sys/block/mdX/md/scan_mode
or a check-and-repair errors with
  echo repair > /sys/block/mdX/md/scan_mode

and read the current state from the same file.

Note: personalities need to know the different between 'check' and 'repair',
but don't yet.  Until they do, 'check' will be the same as 'repair' and will
just do a normal resync pass.

Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 3f294f4f

drivers/md/md.c

+68 −9
Original line number Diff line number Diff line
@@ -1714,9 +1714,60 @@ static struct md_sysfs_entry md_raid_disks = { 
	.show = md_show_rdisks,

};



static ssize_t

md_show_scan(mddev_t *mddev, char *page)

{

	char *type = "none";

	if (mddev->recovery &

	    ((1<<MD_RECOVERY_RUNNING) || (1<<MD_RECOVERY_NEEDED))) {

		if (mddev->recovery & (1<<MD_RECOVERY_SYNC)) {

			if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))

				type = "resync";

			else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))

				type = "check";

			else

				type = "repair";

		} else

			type = "recover";

	}

	return sprintf(page, "%s\n", type);

}



static ssize_t

md_store_scan(mddev_t *mddev, const char *page, size_t len)

{

	int canscan=0;

	if (mddev->recovery &

	    ((1<<MD_RECOVERY_RUNNING) || (1<<MD_RECOVERY_NEEDED)))

		return -EBUSY;

	down(&mddev->reconfig_sem);

	if (mddev->pers && mddev->pers->sync_request)

		canscan=1;

	up(&mddev->reconfig_sem);

	if (!canscan)

		return -EINVAL;



	if (strcmp(page, "check")==0 || strcmp(page, "check\n")==0)

		set_bit(MD_RECOVERY_CHECK, &mddev->recovery);

	else if (strcmp(page, "repair")!=0 && strcmp(page, "repair\n")!=0)

		return -EINVAL;

	set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);

	set_bit(MD_RECOVERY_SYNC, &mddev->recovery);

	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

	md_wakeup_thread(mddev->thread);

	return len;

}



static struct md_sysfs_entry md_scan_mode = {

	.attr = {.name = "scan_mode", .mode = S_IRUGO|S_IWUSR },

	.show = md_show_scan,

	.store = md_store_scan,

};



static struct attribute *md_default_attrs[] = {

	&md_level.attr,

	&md_raid_disks.attr,

	&md_scan_mode.attr,

	NULL,

};
@@ -3855,7 +3906,8 @@ static void md_do_sync(mddev_t *mddev) 


	is_mddev_idle(mddev); /* this also initializes IO event counters */

	/* we don't use the checkpoint if there's a bitmap */

	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap)

	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap

	    && ! test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))

		j = mddev->recovery_cp;

	else

		j = 0;
@@ -4093,9 +4145,13 @@ void md_check_recovery(mddev_t *mddev) 
			set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

			goto unlock;

		}

		if (mddev->recovery)

			/* probably just the RECOVERY_NEEDED flag */

			mddev->recovery = 0;

		/* Clear some bits that don't mean anything, but

		 * might be left set

		 */

		clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

		clear_bit(MD_RECOVERY_ERR, &mddev->recovery);

		clear_bit(MD_RECOVERY_INTR, &mddev->recovery);

		clear_bit(MD_RECOVERY_DONE, &mddev->recovery);



		/* no recovery is running.

		 * remove any failed drives, then
@@ -4129,14 +4185,17 @@ void md_check_recovery(mddev_t *mddev) 
				}

		}



		if (!spares && (mddev->recovery_cp == MaxSector )) {

			/* nothing we can do ... */

		if (spares) {

			clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);

			clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);

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

			set_bit(MD_RECOVERY_SYNC, &mddev->recovery);

		} else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))

			/* nothing to be done ... */

			goto unlock;

		}



		if (mddev->pers->sync_request) {

			set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);

			if (!spares)

				set_bit(MD_RECOVERY_SYNC, &mddev->recovery);

			if (spares && mddev->bitmap && ! mddev->bitmap->file) {

				/* We are adding a device or devices to an array

				 * which has the bitmap stored on all devices.

include/linux/raid/md_k.h

+4 −0
Original line number Diff line number Diff line
@@ -182,6 +182,8 @@ struct mddev_s 
	 * ERR:      and IO error was detected - abort the resync/recovery

	 * INTR:     someone requested a (clean) early abort.

	 * DONE:     thread is done and is waiting to be reaped

	 * REQUEST:  user-space has requested a sync (used with SYNC)

	 * CHECK:    user-space request for for check-only, no repair

	 */

#define	MD_RECOVERY_RUNNING	0

#define	MD_RECOVERY_SYNC	1
@@ -189,6 +191,8 @@ struct mddev_s 
#define	MD_RECOVERY_INTR	3

#define	MD_RECOVERY_DONE	4

#define	MD_RECOVERY_NEEDED	5

#define	MD_RECOVERY_REQUESTED	6

#define	MD_RECOVERY_CHECK	7

	unsigned long			recovery;



	int				in_sync;	/* know to not need resync */

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