[PATCH] md/raid1: clear bitmap when fullsync completes

We need to be careful differentiating between a resync of a complete array,
in which we can clear the bitmap, and a resync of a degraded array, in
which we cannot.

This patch cleans all that up.

Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 24 insertions, 22 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 95980ad6b27b..0c2ed99a3832 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1345,7 +1345,8 @@ void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long secto
         }
 }
 
-int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks)
+int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks,
+                        int degraded)
 {
         bitmap_counter_t *bmc;
         int rv;
@@ -1362,8 +1363,10 @@ int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks)
                         rv = 1;
                 else if (NEEDED(*bmc)) {
                         rv = 1;
-                        *bmc |= RESYNC_MASK;
-                        *bmc &= ~NEEDED_MASK;
+                        if (!degraded) { /* don't set/clear bits if degraded */
+                                *bmc |= RESYNC_MASK;
+                                *bmc &= ~NEEDED_MASK;
+                        }
                 }
         }
         spin_unlock_irq(&bitmap->lock);
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index ff1dbec864af..5f253ee536bb 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1126,21 +1126,19 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
                  * only be one in raid1 resync.
                  * We can find the current addess in mddev->curr_resync
                  */
-                if (!conf->fullsync) {
-                        if (mddev->curr_resync < max_sector)
-                                bitmap_end_sync(mddev->bitmap,
-                                                mddev->curr_resync,
+                if (mddev->curr_resync < max_sector) /* aborted */
+                        bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
                                                 &sync_blocks, 1);
-                        bitmap_close_sync(mddev->bitmap);
-                }
-                if (mddev->curr_resync >= max_sector)
+                else /* completed sync */
                         conf->fullsync = 0;
+
+                bitmap_close_sync(mddev->bitmap);
                 close_sync(conf);
                 return 0;
         }
 
-        if (!conf->fullsync &&
-            !bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks)) {
+        if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, mddev->degraded) &&
+            !conf->fullsync) {
                 /* We can skip this block, and probably several more */
                 *skipped = 1;
                 return sync_blocks;
@@ -1243,15 +1241,15 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
                         len = (max_sector - sector_nr) << 9;
                 if (len == 0)
                         break;
-                if (!conf->fullsync) {
-                        if (sync_blocks == 0) {
-                                if (!bitmap_start_sync(mddev->bitmap,
-                                                       sector_nr, &sync_blocks))
-                                        break;
-                                if (sync_blocks < (PAGE_SIZE>>9))
-                                        BUG();
-                                if (len > (sync_blocks<<9)) len = sync_blocks<<9;
-                        }
+                if (sync_blocks == 0) {
+                        if (!bitmap_start_sync(mddev->bitmap, sector_nr,
+                                        &sync_blocks, mddev->degraded) &&
+                                        !conf->fullsync)
+                                break;
+                        if (sync_blocks < (PAGE_SIZE>>9))
+                                BUG();
+                        if (len > (sync_blocks<<9))
+                                len = sync_blocks<<9;
                 }
 
                 for (i=0 ; i < conf->raid_disks; i++) {
@@ -1264,7 +1262,8 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
                                         while (i > 0) {
                                                 i--;
                                                 bio = r1_bio->bios[i];
-                                                if (bio->bi_end_io==NULL) continue;
+                                                if (bio->bi_end_io==NULL)
+                                                        continue;
                                                 /* remove last page from this bio */
                                                 bio->bi_vcnt--;
                                                 bio->bi_size -= len;