Merge tag 'md/3.14' of git://neil.brown.name/md

Pull md updates from Neil Brown:
 "All bug fixes, two tagged for -stable"

* tag 'md/3.14' of git://neil.brown.name/md:
  md/raid5: close recently introduced race in stripe_head management.
  md/raid5: fix long-standing problem with bitmap handling on write failure.
  md: check command validity early in md_ioctl().
  md: ensure metadata is writen after raid level change.
  md/raid10: avoid fullsync when not necessary.
  md: allow a partially recovered device to be hot-added to an array.
  md: Change handling of save_raid_disk and metadata update during recovery.

4 files changed, 68 insertions, 26 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 369d919bdafe..40c531359a15 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1173,6 +1173,7 @@ static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
                             desc->raid_disk < mddev->raid_disks */) {
                         set_bit(In_sync, &rdev->flags);
                         rdev->raid_disk = desc->raid_disk;
+                        rdev->saved_raid_disk = desc->raid_disk;
                 } else if (desc->state & (1<<MD_DISK_ACTIVE)) {
                         /* active but not in sync implies recovery up to
                          * reshape position.  We don't know exactly where
@@ -1671,10 +1672,14 @@ static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
                         set_bit(Faulty, &rdev->flags);
                         break;
                 default:
+                        rdev->saved_raid_disk = role;
                         if ((le32_to_cpu(sb->feature_map) &
-                             MD_FEATURE_RECOVERY_OFFSET))
+                             MD_FEATURE_RECOVERY_OFFSET)) {
                                 rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
-                        else
+                                if (!(le32_to_cpu(sb->feature_map) &
+                                      MD_FEATURE_RECOVERY_BITMAP))
+                                        rdev->saved_raid_disk = -1;
+                        } else
                                 set_bit(In_sync, &rdev->flags);
                         rdev->raid_disk = role;
                         break;
@@ -1736,6 +1741,9 @@ static void super_1_sync(struct mddev *mddev, struct md_rdev *rdev)
                         cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
                 sb->recovery_offset =
                         cpu_to_le64(rdev->recovery_offset);
+                if (rdev->saved_raid_disk >= 0 && mddev->bitmap)
+                        sb->feature_map |=
+                                cpu_to_le32(MD_FEATURE_RECOVERY_BITMAP);
         }
         if (test_bit(Replacement, &rdev->flags))
                 sb->feature_map |=
@@ -2477,8 +2485,7 @@ repeat:
                 if (rdev->sb_loaded != 1)
                         continue; /* no noise on spare devices */
 
-                if (!test_bit(Faulty, &rdev->flags) &&
-                    rdev->saved_raid_disk == -1) {
+                if (!test_bit(Faulty, &rdev->flags)) {
                         md_super_write(mddev,rdev,
                                        rdev->sb_start, rdev->sb_size,
                                        rdev->sb_page);
@@ -2494,11 +2501,9 @@ repeat:
                                 rdev->badblocks.size = 0;
                         }
 
-                } else if (test_bit(Faulty, &rdev->flags))
+                } else
                         pr_debug("md: %s (skipping faulty)\n",
                                  bdevname(rdev->bdev, b));
-                else
-                        pr_debug("(skipping incremental s/r ");
 
                 if (mddev->level == LEVEL_MULTIPATH)
                         /* only need to write one superblock... */
@@ -2614,6 +2619,8 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
          *  blocked - sets the Blocked flags
          *  -blocked - clears the Blocked and possibly simulates an error
          *  insync - sets Insync providing device isn't active
+         *  -insync - clear Insync for a device with a slot assigned,
+         *            so that it gets rebuilt based on bitmap
          *  write_error - sets WriteErrorSeen
          *  -write_error - clears WriteErrorSeen
          */
@@ -2662,6 +2669,11 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
         } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
                 set_bit(In_sync, &rdev->flags);
                 err = 0;
+        } else if (cmd_match(buf, "-insync") && rdev->raid_disk >= 0) {
+                clear_bit(In_sync, &rdev->flags);
+                rdev->saved_raid_disk = rdev->raid_disk;
+                rdev->raid_disk = -1;
+                err = 0;
         } else if (cmd_match(buf, "write_error")) {
                 set_bit(WriteErrorSeen, &rdev->flags);
                 err = 0;
@@ -3589,6 +3601,8 @@ level_store(struct mddev *mddev, const char *buf, size_t len)
         pers->run(mddev);
         set_bit(MD_CHANGE_DEVS, &mddev->flags);
         mddev_resume(mddev);
+        if (!mddev->thread)
+                md_update_sb(mddev, 1);
         sysfs_notify(&mddev->kobj, NULL, "level");
         md_new_event(mddev);
         return rv;
@@ -5770,6 +5784,7 @@ static int add_new_disk(struct mddev * mddev, mdu_disk_info_t *info)
                                 clear_bit(Bitmap_sync, &rdev->flags);
                         } else
                                 rdev->raid_disk = -1;
+                        rdev->saved_raid_disk = rdev->raid_disk;
                 } else
                         super_types[mddev->major_version].
                                 validate_super(mddev, rdev);
@@ -5782,11 +5797,6 @@ static int add_new_disk(struct mddev * mddev, mdu_disk_info_t *info)
                         return -EINVAL;
                 }
 
-                if (test_bit(In_sync, &rdev->flags))
-                        rdev->saved_raid_disk = rdev->raid_disk;
-                else
-                        rdev->saved_raid_disk = -1;
-
                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
                         set_bit(WriteMostly, &rdev->flags);
@@ -6336,6 +6346,32 @@ static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
         return 0;
 }
 
+static inline bool md_ioctl_valid(unsigned int cmd)
+{
+        switch (cmd) {
+        case ADD_NEW_DISK:
+        case BLKROSET:
+        case GET_ARRAY_INFO:
+        case GET_BITMAP_FILE:
+        case GET_DISK_INFO:
+        case HOT_ADD_DISK:
+        case HOT_REMOVE_DISK:
+        case PRINT_RAID_DEBUG:
+        case RAID_AUTORUN:
+        case RAID_VERSION:
+        case RESTART_ARRAY_RW:
+        case RUN_ARRAY:
+        case SET_ARRAY_INFO:
+        case SET_BITMAP_FILE:
+        case SET_DISK_FAULTY:
+        case STOP_ARRAY:
+        case STOP_ARRAY_RO:
+                return true;
+        default:
+                return false;
+        }
+}
+
 static int md_ioctl(struct block_device *bdev, fmode_t mode,
                         unsigned int cmd, unsigned long arg)
 {
@@ -6344,6 +6380,9 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode,
         struct mddev *mddev = NULL;
         int ro;
 
+        if (!md_ioctl_valid(cmd))
+                return -ENOTTY;
+
         switch (cmd) {
         case RAID_VERSION:
         case GET_ARRAY_INFO:
@@ -7718,7 +7757,8 @@ static int remove_and_add_spares(struct mddev *mddev,
                        !test_bit(Bitmap_sync, &rdev->flags)))
                         continue;
 
-                rdev->recovery_offset = 0;
+                if (rdev->saved_raid_disk < 0)
+                        rdev->recovery_offset = 0;
                 if (mddev->pers->
                     hot_add_disk(mddev, rdev) == 0) {
                         if (sysfs_link_rdev(mddev, rdev))
@@ -7938,14 +7978,10 @@ void md_reap_sync_thread(struct mddev *mddev)
                 mddev->pers->finish_reshape(mddev);
 
         /* If array is no-longer degraded, then any saved_raid_disk
-         * information must be scrapped.  Also if any device is now
-         * In_sync we must scrape the saved_raid_disk for that device
-         * do the superblock for an incrementally recovered device
-         * written out.
+         * information must be scrapped.
          */
-        rdev_for_each(rdev, mddev)
-                if (!mddev->degraded ||
-                    test_bit(In_sync, &rdev->flags))
+        if (!mddev->degraded)
+                rdev_for_each(rdev, mddev)
                         rdev->saved_raid_disk = -1;
 
         md_update_sb(mddev, 1);
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 06eeb99ea6fc..8d39d63281b9 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3747,7 +3747,8 @@ static int run(struct mddev *mddev)
                     !test_bit(In_sync, &disk->rdev->flags)) {
                         disk->head_position = 0;
                         mddev->degraded++;
-                        if (disk->rdev)
+                        if (disk->rdev &&
+                            disk->rdev->saved_raid_disk < 0)
                                 conf->fullsync = 1;
                 }
                 disk->recovery_disabled = mddev->recovery_disabled - 1;
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index cbb15716a5db..03f82ab87d9e 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -675,8 +675,10 @@ get_active_stripe(struct r5conf *conf, sector_t sector,
                                          || !conf->inactive_blocked),
                                         *(conf->hash_locks + hash));
                                 conf->inactive_blocked = 0;
-                        } else
+                        } else {
                                 init_stripe(sh, sector, previous);
+                                atomic_inc(&sh->count);
+                        }
                 } else {
                         spin_lock(&conf->device_lock);
                         if (atomic_read(&sh->count)) {
@@ -695,13 +697,11 @@ get_active_stripe(struct r5conf *conf, sector_t sector,
                                         sh->group = NULL;
                                 }
                         }
+                        atomic_inc(&sh->count);
                         spin_unlock(&conf->device_lock);
                 }
         } while (sh == NULL);
 
-        if (sh)
-                atomic_inc(&sh->count);
-
         spin_unlock_irq(conf->hash_locks + hash);
         return sh;
 }
@@ -2111,6 +2111,7 @@ static void raid5_end_write_request(struct bio *bi, int error)
                         set_bit(R5_MadeGoodRepl, &sh->dev[i].flags);
         } else {
                 if (!uptodate) {
+                        set_bit(STRIPE_DEGRADED, &sh->state);
                         set_bit(WriteErrorSeen, &rdev->flags);
                         set_bit(R5_WriteError, &sh->dev[i].flags);
                         if (!test_and_set_bit(WantReplacement, &rdev->flags))
diff --git a/include/uapi/linux/raid/md_p.h b/include/uapi/linux/raid/md_p.h
index f7cf7f351144..49f4210d4394 100644
--- a/include/uapi/linux/raid/md_p.h
+++ b/include/uapi/linux/raid/md_p.h
@@ -292,6 +292,9 @@ struct mdp_superblock_1 {
                                             * backwards anyway.
                                             */
 #define MD_FEATURE_NEW_OFFSET           64 /* new_offset must be honoured */
+#define MD_FEATURE_RECOVERY_BITMAP      128 /* recovery that is happening
+                                             * is guided by bitmap.
+                                             */
 #define MD_FEATURE_ALL                  (MD_FEATURE_BITMAP_OFFSET       \
                                         |MD_FEATURE_RECOVERY_OFFSET     \
                                         |MD_FEATURE_RESHAPE_ACTIVE      \
@@ -299,6 +302,7 @@ struct mdp_superblock_1 {
                                         |MD_FEATURE_REPLACEMENT         \
                                         |MD_FEATURE_RESHAPE_BACKWARDS   \
                                         |MD_FEATURE_NEW_OFFSET          \
+                                        |MD_FEATURE_RECOVERY_BITMAP     \
                                         )
 
-#endif 
+#endif