Add support for restarting rebuilds on RAID 5.

ok krw@

diff --git a/sys/dev/softraid_raid5.c b/sys/dev/softraid_raid5.c
index 60f9a06..181129a 100644 (file)
--- a/sys/dev/softraid_raid5.c
+++ b/sys/dev/softraid_raid5.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: softraid_raid5.c,v 1.17 2014/11/18 02:37:30 tedu Exp $ */
+/* $OpenBSD: softraid_raid5.c,v 1.18 2015/04/11 16:23:34 jsing Exp $ */
 /*
  * Copyright (c) 2014 Joel Sing <jsing@openbsd.org>
  * Copyright (c) 2009 Marco Peereboom <marco@peereboom.us>
@@ -766,7 +766,7 @@ sr_raid5_xor(void *a, void *b, int len)
 void
 sr_raid5_rebuild(struct sr_discipline *sd)
 {
-       int64_t strip_no, strip_size, strip_bits, i, psz, rb;
+       int64_t strip_no, strip_size, strip_bits, i, psz, rb, restart;
        int64_t chunk_count, chunk_strips, chunk_lba, chunk_size, row_size;
        struct sr_workunit *wu_r, *wu_w;
        int s, slept, percent = 0, old_percent = -1;
@@ -790,14 +790,30 @@ sr_raid5_rebuild(struct sr_discipline *sd)
        chunk_strips = (chunk_size << DEV_BSHIFT) >> strip_bits;
        row_size = (chunk_count << strip_bits) >> DEV_BSHIFT;
 
-       /* XXX - handle restarts. */
        DNPRINTF(SR_D_REBUILD, "%s: %s sr_raid5_rebuild volume size = %lld, "
            "chunk count = %lld, chunk size = %lld, chunk strips = %lld, "
            "row size = %lld\n", DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
            sd->sd_meta->ssdi.ssd_size, chunk_count, chunk_size, chunk_strips,
            row_size);
 
-       for (strip_no = 0; strip_no < chunk_strips; strip_no++) {
+       restart = sd->sd_meta->ssd_rebuild / row_size;
+       if (restart > chunk_strips) {
+               printf("%s: bogus rebuild restart offset, starting from 0\n",
+                   DEVNAME(sd->sd_sc));
+               restart = 0;
+       }
+       if (restart != 0) {
+               psz = sd->sd_meta->ssdi.ssd_size;
+               rb = sd->sd_meta->ssd_rebuild;
+               if (rb > 0)
+                       percent = 100 - ((psz * 100 - rb * 100) / psz) - 1;
+               else
+                       percent = 0;
+               printf("%s: resuming rebuild on %s at %d%%\n",
+                   DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname, percent);
+       }
+
+       for (strip_no = restart; strip_no < chunk_strips; strip_no++) {
                chunk_lba = (strip_size >> DEV_BSHIFT) * strip_no +
                    sd->sd_meta->ssd_data_offset;