Merge branch 'for-linus' of git://neil.brown.name/md

* 'for-linus' of git://neil.brown.name/md:
  md: cancel check/repair requests when recovery is needed
  Allow raid10 resync to happening in larger chunks.
  Allow faulty devices to be removed from a readonly array.
  Don't let a blocked_rdev interfere with read request in raid5/6
  Fail safely when trying to grow an array with a write-intent bitmap.
  Restore force switch of md array to readonly at reboot time.
  Make writes to md/safe_mode_delay immediately effective.

3 files changed, 59 insertions, 15 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index c7aae66c6f9b..8cfadc5bd2ba 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2393,6 +2393,8 @@ static void analyze_sbs(mddev_t * mddev)
 
 }
 
+static void md_safemode_timeout(unsigned long data);
+
 static ssize_t
 safe_delay_show(mddev_t *mddev, char *page)
 {
@@ -2432,9 +2434,12 @@ safe_delay_store(mddev_t *mddev, const char *cbuf, size_t len)
         if (msec == 0)
                 mddev->safemode_delay = 0;
         else {
+                unsigned long old_delay = mddev->safemode_delay;
                 mddev->safemode_delay = (msec*HZ)/1000;
                 if (mddev->safemode_delay == 0)
                         mddev->safemode_delay = 1;
+                if (mddev->safemode_delay < old_delay)
+                        md_safemode_timeout((unsigned long)mddev);
         }
         return len;
 }
@@ -4634,6 +4639,11 @@ static int update_size(mddev_t *mddev, sector_t num_sectors)
          */
         if (mddev->sync_thread)
                 return -EBUSY;
+        if (mddev->bitmap)
+                /* Sorry, cannot grow a bitmap yet, just remove it,
+                 * grow, and re-add.
+                 */
+                return -EBUSY;
         rdev_for_each(rdev, tmp, mddev) {
                 sector_t avail;
                 avail = rdev->size * 2;
@@ -5993,7 +6003,7 @@ static int remove_and_add_spares(mddev_t *mddev)
                         }
                 }
 
-        if (mddev->degraded) {
+        if (mddev->degraded && ! mddev->ro) {
                 rdev_for_each(rdev, rtmp, mddev) {
                         if (rdev->raid_disk >= 0 &&
                             !test_bit(In_sync, &rdev->flags) &&
@@ -6067,6 +6077,8 @@ void md_check_recovery(mddev_t *mddev)
                 flush_signals(current);
         }
 
+        if (mddev->ro && !test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
+                return;
         if ( ! (
                 (mddev->flags && !mddev->external) ||
                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
@@ -6080,6 +6092,15 @@ void md_check_recovery(mddev_t *mddev)
         if (mddev_trylock(mddev)) {
                 int spares = 0;
 
+                if (mddev->ro) {
+                        /* Only thing we do on a ro array is remove
+                         * failed devices.
+                         */
+                        remove_and_add_spares(mddev);
+                        clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+                        goto unlock;
+                }
+
                 if (!mddev->external) {
                         int did_change = 0;
                         spin_lock_irq(&mddev->write_lock);
@@ -6117,7 +6138,8 @@ void md_check_recovery(mddev_t *mddev)
                         /* resync has finished, collect result */
                         md_unregister_thread(mddev->sync_thread);
                         mddev->sync_thread = NULL;
-                        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
+                        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
+                            !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
                                 /* success...*/
                                 /* activate any spares */
                                 if (mddev->pers->spare_active(mddev))
@@ -6169,6 +6191,7 @@ void md_check_recovery(mddev_t *mddev)
                 } else if ((spares = remove_and_add_spares(mddev))) {
                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
+                        clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
                 } else if (mddev->recovery_cp < MaxSector) {
                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
@@ -6232,7 +6255,11 @@ static int md_notify_reboot(struct notifier_block *this,
 
                 for_each_mddev(mddev, tmp)
                         if (mddev_trylock(mddev)) {
-                                do_md_stop (mddev, 1, 0);
+                                /* Force a switch to readonly even array
+                                 * appears to still be in use.  Hence
+                                 * the '100'.
+                                 */
+                                do_md_stop (mddev, 1, 100);
                                 mddev_unlock(mddev);
                         }
                 /*
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index d41bebb6da0f..e34cd0e62473 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -76,11 +76,13 @@ static void r10bio_pool_free(void *r10_bio, void *data)
         kfree(r10_bio);
 }
 
+/* Maximum size of each resync request */
 #define RESYNC_BLOCK_SIZE (64*1024)
-//#define RESYNC_BLOCK_SIZE PAGE_SIZE
-#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
 #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
-#define RESYNC_WINDOW (2048*1024)
+/* amount of memory to reserve for resync requests */
+#define RESYNC_WINDOW (1024*1024)
+/* maximum number of concurrent requests, memory permitting */
+#define RESYNC_DEPTH (32*1024*1024/RESYNC_BLOCK_SIZE)
 
 /*
  * When performing a resync, we need to read and compare, so
@@ -690,7 +692,6 @@ static int flush_pending_writes(conf_t *conf)
  *    there is no normal IO happeing.  It must arrange to call
  *    lower_barrier when the particular background IO completes.
  */
-#define RESYNC_DEPTH 32
 
 static void raise_barrier(conf_t *conf, int force)
 {
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 40e939675657..224de022e7c5 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2568,10 +2568,10 @@ static bool handle_stripe5(struct stripe_head *sh)
                 if (dev->written)
                         s.written++;
                 rdev = rcu_dereference(conf->disks[i].rdev);
-                if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
+                if (blocked_rdev == NULL &&
+                    rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
                         blocked_rdev = rdev;
                         atomic_inc(&rdev->nr_pending);
-                        break;
                 }
                 if (!rdev || !test_bit(In_sync, &rdev->flags)) {
                         /* The ReadError flag will just be confusing now */
@@ -2588,8 +2588,14 @@ static bool handle_stripe5(struct stripe_head *sh)
         rcu_read_unlock();
 
         if (unlikely(blocked_rdev)) {
-                set_bit(STRIPE_HANDLE, &sh->state);
-                goto unlock;
+                if (s.syncing || s.expanding || s.expanded ||
+                    s.to_write || s.written) {
+                        set_bit(STRIPE_HANDLE, &sh->state);
+                        goto unlock;
+                }
+                /* There is nothing for the blocked_rdev to block */
+                rdev_dec_pending(blocked_rdev, conf->mddev);
+                blocked_rdev = NULL;
         }
 
         if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) {
@@ -2832,10 +2838,10 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
                 if (dev->written)
                         s.written++;
                 rdev = rcu_dereference(conf->disks[i].rdev);
-                if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
+                if (blocked_rdev == NULL &&
+                    rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
                         blocked_rdev = rdev;
                         atomic_inc(&rdev->nr_pending);
-                        break;
                 }
                 if (!rdev || !test_bit(In_sync, &rdev->flags)) {
                         /* The ReadError flag will just be confusing now */
@@ -2853,9 +2859,16 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
         rcu_read_unlock();
 
         if (unlikely(blocked_rdev)) {
-                set_bit(STRIPE_HANDLE, &sh->state);
-                goto unlock;
+                if (s.syncing || s.expanding || s.expanded ||
+                    s.to_write || s.written) {
+                        set_bit(STRIPE_HANDLE, &sh->state);
+                        goto unlock;
+                }
+                /* There is nothing for the blocked_rdev to block */
+                rdev_dec_pending(blocked_rdev, conf->mddev);
+                blocked_rdev = NULL;
         }
+
         pr_debug("locked=%d uptodate=%d to_read=%d"
                " to_write=%d failed=%d failed_num=%d,%d\n",
                s.locked, s.uptodate, s.to_read, s.to_write, s.failed,
@@ -4446,6 +4459,9 @@ static int raid5_check_reshape(mddev_t *mddev)
                 return -EINVAL; /* Cannot shrink array or change level yet */
         if (mddev->delta_disks == 0)
                 return 0; /* nothing to do */
+        if (mddev->bitmap)
+                /* Cannot grow a bitmap yet */
+                return -EBUSY;
 
         /* Can only proceed if there are plenty of stripe_heads.
          * We need a minimum of one full stripe,, and for sensible progress