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@xxxxxxx>
### Diffstat output
./drivers/md/md.c | 18 ++++++++++++++++--
./drivers/md/raid5.c | 5 +++++
./include/linux/raid/md_k.h | 4 ++++
3 files changed, 25 insertions(+), 2 deletions(-)
diff ./drivers/md/md.c~current~ ./drivers/md/md.c
--- ./drivers/md/md.c~current~ 2005-10-04 14:19:35.000000000 +1000
+++ ./drivers/md/md.c 2005-10-04 14:42:04.000000000 +1000
@@ -1758,16 +1758,29 @@ md_store_scan(mddev_t *mddev, const char
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,
};
@@ -3884,12 +3897,13 @@ 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;
diff ./drivers/md/raid5.c~current~ ./drivers/md/raid5.c
--- ./drivers/md/raid5.c~current~ 2005-10-04 13:08:44.000000000 +1000
+++ ./drivers/md/raid5.c 2005-10-04 14:42:32.000000000 +1000
@@ -1292,6 +1292,11 @@ static void handle_stripe(struct stripe_
!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)) {
diff ./include/linux/raid/md_k.h~current~ ./include/linux/raid/md_k.h
--- ./include/linux/raid/md_k.h~current~ 2005-10-04 14:15:54.000000000 +1000
+++ ./include/linux/raid/md_k.h 2005-10-04 14:35:29.000000000 +1000
@@ -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
-
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
