[PATCH] md: teach raid5 the difference between 'check' and 'repair'.

With this, raid5 can be asked to check parity without repairing it.  It also
keeps a count of the number of incorrect parity blocks found (mismatches) and
reports them through sysfs.

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
NeilBrown 2005-11-08 21:39:26 -08:00 committed by Linus Torvalds
parent 24dd469d72
commit 9d88883e68
3 changed files with 25 additions and 2 deletions

View File

@ -1758,16 +1758,29 @@ md_store_scan(mddev_t *mddev, const char *page, size_t len)
return len;
}
static ssize_t
md_show_mismatch(mddev_t *mddev, char *page)
{
return sprintf(page, "%llu\n",
(unsigned long long) mddev->resync_mismatches);
}
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 md_sysfs_entry md_mismatches = {
.attr = {.name = "mismatch_cnt", .mode = S_IRUGO },
.show = md_show_mismatch,
};
static struct attribute *md_default_attrs[] = {
&md_level.attr,
&md_raid_disks.attr,
&md_scan_mode.attr,
&md_mismatches.attr,
NULL,
};
@ -3888,12 +3901,13 @@ static void md_do_sync(mddev_t *mddev)
}
} while (mddev->curr_resync < 2);
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
/* resync follows the size requested by the personality,
* which defaults to physical size, but can be virtual size
*/
max_sectors = mddev->resync_max_sectors;
else
mddev->resync_mismatches = 0;
} else
/* recovery follows the physical size of devices */
max_sectors = mddev->size << 1;

View File

@ -1292,6 +1292,11 @@ static void handle_stripe(struct stripe_head *sh)
!memcmp(pagea, pagea+4, STRIPE_SIZE-4)) {
/* parity is correct (on disc, not in buffer any more) */
set_bit(STRIPE_INSYNC, &sh->state);
} else {
conf->mddev->resync_mismatches += STRIPE_SECTORS;
if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery))
/* don't try to repair!! */
set_bit(STRIPE_INSYNC, &sh->state);
}
}
if (!test_bit(STRIPE_INSYNC, &sh->state)) {

View File

@ -175,6 +175,10 @@ struct mddev_s
sector_t resync_mark_cnt;/* blocks written at resync_mark */
sector_t resync_max_sectors; /* may be set by personality */
sector_t resync_mismatches; /* count of sectors where
* parity/replica mismatch found
*/
/* recovery/resync flags
* NEEDED: we might need to start a resync/recover
* RUNNING: a thread is running, or about to be started