1 files changed, 115 insertions, 108 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 54ef8d75541d..cac6f4d3a143 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1617,8 +1617,8 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector,
         sector_t new_sector;
         int algorithm = previous ? conf->prev_algo
                                  : conf->algorithm;
-        int sectors_per_chunk = previous ? (conf->prev_chunk >> 9)
-                                         : (conf->chunk_size >> 9);
+        int sectors_per_chunk = previous ? conf->prev_chunk_sectors
+                                         : conf->chunk_sectors;
         int raid_disks = previous ? conf->previous_raid_disks
                                   : conf->raid_disks;
         int data_disks = raid_disks - conf->max_degraded;
@@ -1823,8 +1823,8 @@ static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous)
         int raid_disks = sh->disks;
         int data_disks = raid_disks - conf->max_degraded;
         sector_t new_sector = sh->sector, check;
-        int sectors_per_chunk = previous ? (conf->prev_chunk >> 9)
-                                         : (conf->chunk_size >> 9);
+        int sectors_per_chunk = previous ? conf->prev_chunk_sectors
+                                         : conf->chunk_sectors;
         int algorithm = previous ? conf->prev_algo
                                  : conf->algorithm;
         sector_t stripe;
@@ -2098,8 +2098,7 @@ static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous,
                             struct stripe_head *sh)
 {
         int sectors_per_chunk =
-                previous ? (conf->prev_chunk >> 9)
-                         : (conf->chunk_size >> 9);
+                previous ? conf->prev_chunk_sectors : conf->chunk_sectors;
         int dd_idx;
         int chunk_offset = sector_div(stripe, sectors_per_chunk);
         int disks = previous ? conf->previous_raid_disks : conf->raid_disks;
@@ -3496,7 +3495,7 @@ static void activate_bit_delay(raid5_conf_t *conf)
 
 static void unplug_slaves(mddev_t *mddev)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         int i;
 
         rcu_read_lock();
@@ -3520,7 +3519,7 @@ static void unplug_slaves(mddev_t *mddev)
 static void raid5_unplug_device(struct request_queue *q)
 {
         mddev_t *mddev = q->queuedata;
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         unsigned long flags;
 
         spin_lock_irqsave(&conf->device_lock, flags);
@@ -3539,7 +3538,7 @@ static void raid5_unplug_device(struct request_queue *q)
 static int raid5_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
 
         /* No difference between reads and writes.  Just check
          * how busy the stripe_cache is
@@ -3564,14 +3563,14 @@ static int raid5_mergeable_bvec(struct request_queue *q,
         mddev_t *mddev = q->queuedata;
         sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
         int max;
-        unsigned int chunk_sectors = mddev->chunk_size >> 9;
+        unsigned int chunk_sectors = mddev->chunk_sectors;
         unsigned int bio_sectors = bvm->bi_size >> 9;
 
         if ((bvm->bi_rw & 1) == WRITE)
                 return biovec->bv_len; /* always allow writes to be mergeable */
 
-        if (mddev->new_chunk < mddev->chunk_size)
-                chunk_sectors = mddev->new_chunk >> 9;
+        if (mddev->new_chunk_sectors < mddev->chunk_sectors)
+                chunk_sectors = mddev->new_chunk_sectors;
         max =  (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9;
         if (max < 0) max = 0;
         if (max <= biovec->bv_len && bio_sectors == 0)
@@ -3584,11 +3583,11 @@ static int raid5_mergeable_bvec(struct request_queue *q,
 static int in_chunk_boundary(mddev_t *mddev, struct bio *bio)
 {
         sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev);
-        unsigned int chunk_sectors = mddev->chunk_size >> 9;
+        unsigned int chunk_sectors = mddev->chunk_sectors;
         unsigned int bio_sectors = bio->bi_size >> 9;
 
-        if (mddev->new_chunk < mddev->chunk_size)
-                chunk_sectors = mddev->new_chunk >> 9;
+        if (mddev->new_chunk_sectors < mddev->chunk_sectors)
+                chunk_sectors = mddev->new_chunk_sectors;
         return  chunk_sectors >=
                 ((sector & (chunk_sectors - 1)) + bio_sectors);
 }
@@ -3652,7 +3651,7 @@ static void raid5_align_endio(struct bio *bi, int error)
         bio_put(bi);
 
         mddev = raid_bi->bi_bdev->bd_disk->queue->queuedata;
-        conf = mddev_to_conf(mddev);
+        conf = mddev->private;
         rdev = (void*)raid_bi->bi_next;
         raid_bi->bi_next = NULL;
 
@@ -3675,10 +3674,10 @@ static int bio_fits_rdev(struct bio *bi)
 {
         struct request_queue *q = bdev_get_queue(bi->bi_bdev);
 
-        if ((bi->bi_size>>9) > q->max_sectors)
+        if ((bi->bi_size>>9) > queue_max_sectors(q))
                 return 0;
         blk_recount_segments(q, bi);
-        if (bi->bi_phys_segments > q->max_phys_segments)
+        if (bi->bi_phys_segments > queue_max_phys_segments(q))
                 return 0;
 
         if (q->merge_bvec_fn)
@@ -3694,7 +3693,7 @@ static int bio_fits_rdev(struct bio *bi)
 static int chunk_aligned_read(struct request_queue *q, struct bio * raid_bio)
 {
         mddev_t *mddev = q->queuedata;
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         unsigned int dd_idx;
         struct bio* align_bi;
         mdk_rdev_t *rdev;
@@ -3811,7 +3810,7 @@ static struct stripe_head *__get_priority_stripe(raid5_conf_t *conf)
 static int make_request(struct request_queue *q, struct bio * bi)
 {
         mddev_t *mddev = q->queuedata;
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         int dd_idx;
         sector_t new_sector;
         sector_t logical_sector, last_sector;
@@ -3908,6 +3907,7 @@ static int make_request(struct request_queue *q, struct bio * bi)
                                 spin_unlock_irq(&conf->device_lock);
                                 if (must_retry) {
                                         release_stripe(sh);
+                                        schedule();
                                         goto retry;
                                 }
                         }
@@ -4003,10 +4003,10 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
          * If old and new chunk sizes differ, we need to process the
          * largest of these
          */
-        if (mddev->new_chunk > mddev->chunk_size)
-                reshape_sectors = mddev->new_chunk / 512;
+        if (mddev->new_chunk_sectors > mddev->chunk_sectors)
+                reshape_sectors = mddev->new_chunk_sectors;
         else
-                reshape_sectors = mddev->chunk_size / 512;
+                reshape_sectors = mddev->chunk_sectors;
 
         /* we update the metadata when there is more than 3Meg
          * in the block range (that is rather arbitrary, should
@@ -4129,7 +4129,7 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
                                      1, &dd_idx, NULL);
         last_sector =
                 raid5_compute_sector(conf, ((stripe_addr+reshape_sectors)
-                                            *(new_data_disks) - 1),
+                                            * new_data_disks - 1),
                                      1, &dd_idx, NULL);
         if (last_sector >= mddev->dev_sectors)
                 last_sector = mddev->dev_sectors - 1;
@@ -4158,7 +4158,7 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
                 wait_event(conf->wait_for_overlap,
                            atomic_read(&conf->reshape_stripes) == 0);
                 mddev->reshape_position = conf->reshape_progress;
-                mddev->curr_resync_completed = mddev->curr_resync;
+                mddev->curr_resync_completed = mddev->curr_resync + reshape_sectors;
                 conf->reshape_checkpoint = jiffies;
                 set_bit(MD_CHANGE_DEVS, &mddev->flags);
                 md_wakeup_thread(mddev->thread);
@@ -4371,7 +4371,7 @@ static void synchronize_stripe_processing(struct list_head *domain)
 static void raid5d(mddev_t *mddev)
 {
         struct stripe_head *sh;
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         int handled;
         LIST_HEAD(raid_domain);
 
@@ -4428,7 +4428,7 @@ static void raid5d(mddev_t *mddev)
 static ssize_t
 raid5_show_stripe_cache_size(mddev_t *mddev, char *page)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         if (conf)
                 return sprintf(page, "%d\n", conf->max_nr_stripes);
         else
@@ -4438,7 +4438,7 @@ raid5_show_stripe_cache_size(mddev_t *mddev, char *page)
 static ssize_t
 raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         unsigned long new;
         int err;
 
@@ -4476,7 +4476,7 @@ raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR,
 static ssize_t
 raid5_show_preread_threshold(mddev_t *mddev, char *page)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         if (conf)
                 return sprintf(page, "%d\n", conf->bypass_threshold);
         else
@@ -4486,7 +4486,7 @@ raid5_show_preread_threshold(mddev_t *mddev, char *page)
 static ssize_t
 raid5_store_preread_threshold(mddev_t *mddev, const char *page, size_t len)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         unsigned long new;
         if (len >= PAGE_SIZE)
                 return -EINVAL;
@@ -4510,7 +4510,7 @@ raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold,
 static ssize_t
 stripe_cache_active_show(mddev_t *mddev, char *page)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         if (conf)
                 return sprintf(page, "%d\n", atomic_read(&conf->active_stripes));
         else
@@ -4534,7 +4534,7 @@ static struct attribute_group raid5_attrs_group = {
 static sector_t
 raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
 
         if (!sectors)
                 sectors = mddev->dev_sectors;
@@ -4546,8 +4546,8 @@ raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks)
                         raid_disks = conf->previous_raid_disks;
         }
 
-        sectors &= ~((sector_t)mddev->chunk_size/512 - 1);
-        sectors &= ~((sector_t)mddev->new_chunk/512 - 1);
+        sectors &= ~((sector_t)mddev->chunk_sectors - 1);
+        sectors &= ~((sector_t)mddev->new_chunk_sectors - 1);
         return sectors * (raid_disks - conf->max_degraded);
 }
 
@@ -4691,9 +4691,11 @@ static raid5_conf_t *setup_conf(mddev_t *mddev)
                 return ERR_PTR(-EINVAL);
         }
 
-        if (!mddev->new_chunk || mddev->new_chunk % PAGE_SIZE) {
+        if (!mddev->new_chunk_sectors ||
+            (mddev->new_chunk_sectors << 9) % PAGE_SIZE ||
+            !is_power_of_2(mddev->new_chunk_sectors)) {
                 printk(KERN_ERR "raid5: invalid chunk size %d for %s\n",
-                        mddev->new_chunk, mdname(mddev));
+                       mddev->new_chunk_sectors << 9, mdname(mddev));
                 return ERR_PTR(-EINVAL);
         }
 
@@ -4756,7 +4758,8 @@ static raid5_conf_t *setup_conf(mddev_t *mddev)
                         conf->fullsync = 1;
         }
 
-        conf->chunk_size = mddev->new_chunk;
+        conf->chunk_sectors = mddev->new_chunk_sectors;
+        conf->level = mddev->new_level;
         if (conf->level == 6)
                 conf->max_degraded = 2;
         else
@@ -4765,7 +4768,7 @@ static raid5_conf_t *setup_conf(mddev_t *mddev)
         conf->max_nr_stripes = NR_STRIPES;
         conf->reshape_progress = mddev->reshape_position;
         if (conf->reshape_progress != MaxSector) {
-                conf->prev_chunk = mddev->chunk_size;
+                conf->prev_chunk_sectors = mddev->chunk_sectors;
                 conf->prev_algo = mddev->layout;
         }
 
@@ -4803,6 +4806,10 @@ static int run(mddev_t *mddev)
         int working_disks = 0;
         mdk_rdev_t *rdev;
 
+        if (mddev->recovery_cp != MaxSector)
+                printk(KERN_NOTICE "raid5: %s is not clean"
+                       " -- starting background reconstruction\n",
+                       mdname(mddev));
         if (mddev->reshape_position != MaxSector) {
                 /* Check that we can continue the reshape.
                  * Currently only disks can change, it must
@@ -4825,7 +4832,7 @@ static int run(mddev_t *mddev)
                  * geometry.
                  */
                 here_new = mddev->reshape_position;
-                if (sector_div(here_new, (mddev->new_chunk>>9)*
+                if (sector_div(here_new, mddev->new_chunk_sectors *
                                (mddev->raid_disks - max_degraded))) {
                         printk(KERN_ERR "raid5: reshape_position not "
                                "on a stripe boundary\n");
@@ -4833,7 +4840,7 @@ static int run(mddev_t *mddev)
                 }
                 /* here_new is the stripe we will write to */
                 here_old = mddev->reshape_position;
-                sector_div(here_old, (mddev->chunk_size>>9)*
+                sector_div(here_old, mddev->chunk_sectors *
                            (old_disks-max_degraded));
                 /* here_old is the first stripe that we might need to read
                  * from */
@@ -4848,7 +4855,7 @@ static int run(mddev_t *mddev)
         } else {
                 BUG_ON(mddev->level != mddev->new_level);
                 BUG_ON(mddev->layout != mddev->new_layout);
-                BUG_ON(mddev->chunk_size != mddev->new_chunk);
+                BUG_ON(mddev->chunk_sectors != mddev->new_chunk_sectors);
                 BUG_ON(mddev->delta_disks != 0);
         }
 
@@ -4882,7 +4889,7 @@ static int run(mddev_t *mddev)
         }
 
         /* device size must be a multiple of chunk size */
-        mddev->dev_sectors &= ~(mddev->chunk_size / 512 - 1);
+        mddev->dev_sectors &= ~(mddev->chunk_sectors - 1);
         mddev->resync_max_sectors = mddev->dev_sectors;
 
         if (mddev->degraded > 0 &&
@@ -4931,7 +4938,7 @@ static int run(mddev_t *mddev)
         {
                 int data_disks = conf->previous_raid_disks - conf->max_degraded;
                 int stripe = data_disks *
-                        (mddev->chunk_size / PAGE_SIZE);
+                        ((mddev->chunk_sectors << 9) / PAGE_SIZE);
                 if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
                         mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
         }
@@ -5021,7 +5028,8 @@ static void status(struct seq_file *seq, mddev_t *mddev)
         raid5_conf_t *conf = (raid5_conf_t *) mddev->private;
         int i;
 
-        seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout);
+        seq_printf(seq, " level %d, %dk chunk, algorithm %d", mddev->level,
+                mddev->chunk_sectors / 2, mddev->layout);
         seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded);
         for (i = 0; i < conf->raid_disks; i++)
                 seq_printf (seq, "%s",
@@ -5169,7 +5177,7 @@ static int raid5_resize(mddev_t *mddev, sector_t sectors)
          * any io in the removed space completes, but it hardly seems
          * worth it.
          */
-        sectors &= ~((sector_t)mddev->chunk_size/512 - 1);
+        sectors &= ~((sector_t)mddev->chunk_sectors - 1);
         md_set_array_sectors(mddev, raid5_size(mddev, sectors,
                                                mddev->raid_disks));
         if (mddev->array_sectors >
@@ -5186,14 +5194,37 @@ static int raid5_resize(mddev_t *mddev, sector_t sectors)
         return 0;
 }
 
-static int raid5_check_reshape(mddev_t *mddev)
+static int check_stripe_cache(mddev_t *mddev)
+{
+        /* Can only proceed if there are plenty of stripe_heads.
+         * We need a minimum of one full stripe,, and for sensible progress
+         * it is best to have about 4 times that.
+         * If we require 4 times, then the default 256 4K stripe_heads will
+         * allow for chunk sizes up to 256K, which is probably OK.
+         * If the chunk size is greater, user-space should request more
+         * stripe_heads first.
+         */
+        raid5_conf_t *conf = mddev->private;
+        if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4
+            > conf->max_nr_stripes ||
+            ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4
+            > conf->max_nr_stripes) {
+                printk(KERN_WARNING "raid5: reshape: not enough stripes.  Needed %lu\n",
+                       ((max(mddev->chunk_sectors, mddev->new_chunk_sectors) << 9)
+                        / STRIPE_SIZE)*4);
+                return 0;
+        }
+        return 1;
+}
+
+static int check_reshape(mddev_t *mddev)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
 
         if (mddev->delta_disks == 0 &&
             mddev->new_layout == mddev->layout &&
-            mddev->new_chunk == mddev->chunk_size)
-                return -EINVAL; /* nothing to do */
+            mddev->new_chunk_sectors == mddev->chunk_sectors)
+                return 0; /* nothing to do */
         if (mddev->bitmap)
                 /* Cannot grow a bitmap yet */
                 return -EBUSY;
@@ -5212,28 +5243,15 @@ static int raid5_check_reshape(mddev_t *mddev)
                         return -EINVAL;
         }
 
-        /* Can only proceed if there are plenty of stripe_heads.
-         * We need a minimum of one full stripe,, and for sensible progress
-         * it is best to have about 4 times that.
-         * If we require 4 times, then the default 256 4K stripe_heads will
-         * allow for chunk sizes up to 256K, which is probably OK.
-         * If the chunk size is greater, user-space should request more
-         * stripe_heads first.
-         */
-        if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes ||
-            (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) {
-                printk(KERN_WARNING "raid5: reshape: not enough stripes.  Needed %lu\n",
-                       (max(mddev->chunk_size, mddev->new_chunk)
-                        / STRIPE_SIZE)*4);
+        if (!check_stripe_cache(mddev))
                 return -ENOSPC;
-        }
 
         return resize_stripes(conf, conf->raid_disks + mddev->delta_disks);
 }
 
 static int raid5_start_reshape(mddev_t *mddev)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
         mdk_rdev_t *rdev;
         int spares = 0;
         int added_devices = 0;
@@ -5242,6 +5260,9 @@ static int raid5_start_reshape(mddev_t *mddev)
         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
                 return -EBUSY;
 
+        if (!check_stripe_cache(mddev))
+                return -ENOSPC;
+
         list_for_each_entry(rdev, &mddev->disks, same_set)
                 if (rdev->raid_disk < 0 &&
                     !test_bit(Faulty, &rdev->flags))
@@ -5268,8 +5289,8 @@ static int raid5_start_reshape(mddev_t *mddev)
         spin_lock_irq(&conf->device_lock);
         conf->previous_raid_disks = conf->raid_disks;
         conf->raid_disks += mddev->delta_disks;
-        conf->prev_chunk = conf->chunk_size;
-        conf->chunk_size = mddev->new_chunk;
+        conf->prev_chunk_sectors = conf->chunk_sectors;
+        conf->chunk_sectors = mddev->new_chunk_sectors;
         conf->prev_algo = conf->algorithm;
         conf->algorithm = mddev->new_layout;
         if (mddev->delta_disks < 0)
@@ -5351,7 +5372,7 @@ static void end_reshape(raid5_conf_t *conf)
                  */
                 {
                         int data_disks = conf->raid_disks - conf->max_degraded;
-                        int stripe = data_disks * (conf->chunk_size
+                        int stripe = data_disks * ((conf->chunk_sectors << 9)
                                                    / PAGE_SIZE);
                         if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
                                 conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
@@ -5365,7 +5386,7 @@ static void end_reshape(raid5_conf_t *conf)
 static void raid5_finish_reshape(mddev_t *mddev)
 {
         struct block_device *bdev;
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
 
         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
 
@@ -5396,7 +5417,7 @@ static void raid5_finish_reshape(mddev_t *mddev)
                                 raid5_remove_disk(mddev, d);
                 }
                 mddev->layout = conf->algorithm;
-                mddev->chunk_size = conf->chunk_size;
+                mddev->chunk_sectors = conf->chunk_sectors;
                 mddev->reshape_position = MaxSector;
                 mddev->delta_disks = 0;
         }
@@ -5404,7 +5425,7 @@ static void raid5_finish_reshape(mddev_t *mddev)
 
 static void raid5_quiesce(mddev_t *mddev, int state)
 {
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
 
         switch(state) {
         case 2: /* resume for a suspend */
@@ -5454,7 +5475,7 @@ static void *raid5_takeover_raid1(mddev_t *mddev)
 
         mddev->new_level = 5;
         mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC;
-        mddev->new_chunk = chunksect << 9;
+        mddev->new_chunk_sectors = chunksect;
 
         return setup_conf(mddev);
 }
@@ -5493,24 +5514,24 @@ static void *raid5_takeover_raid6(mddev_t *mddev)
 }
 
 
-static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk)
+static int raid5_check_reshape(mddev_t *mddev)
 {
         /* For a 2-drive array, the layout and chunk size can be changed
          * immediately as not restriping is needed.
          * For larger arrays we record the new value - after validation
          * to be used by a reshape pass.
          */
-        raid5_conf_t *conf = mddev_to_conf(mddev);
+        raid5_conf_t *conf = mddev->private;
+        int new_chunk = mddev->new_chunk_sectors;
 
-        if (new_layout >= 0 && !algorithm_valid_raid5(new_layout))
+        if (mddev->new_layout >= 0 && !algorithm_valid_raid5(mddev->new_layout))
                 return -EINVAL;
         if (new_chunk > 0) {
-                if (new_chunk & (new_chunk-1))
-                        /* not a power of 2 */
+                if (!is_power_of_2(new_chunk))
                         return -EINVAL;
-                if (new_chunk < PAGE_SIZE)
+                if (new_chunk < (PAGE_SIZE>>9))
                         return -EINVAL;
-                if (mddev->array_sectors & ((new_chunk>>9)-1))
+                if (mddev->array_sectors & (new_chunk-1))
                         /* not factor of array size */
                         return -EINVAL;
         }
@@ -5518,49 +5539,39 @@ static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk)
         /* They look valid */
 
         if (mddev->raid_disks == 2) {
-
-                if (new_layout >= 0) {
-                        conf->algorithm = new_layout;
-                        mddev->layout = mddev->new_layout = new_layout;
+                /* can make the change immediately */
+                if (mddev->new_layout >= 0) {
+                        conf->algorithm = mddev->new_layout;
+                        mddev->layout = mddev->new_layout;
                 }
                 if (new_chunk > 0) {
-                        conf->chunk_size = new_chunk;
-                        mddev->chunk_size = mddev->new_chunk = new_chunk;
+                        conf->chunk_sectors = new_chunk ;
+                        mddev->chunk_sectors = new_chunk;
                 }
                 set_bit(MD_CHANGE_DEVS, &mddev->flags);
                 md_wakeup_thread(mddev->thread);
-        } else {
-                if (new_layout >= 0)
-                        mddev->new_layout = new_layout;
-                if (new_chunk > 0)
-                        mddev->new_chunk = new_chunk;
         }
-        return 0;
+        return check_reshape(mddev);
 }
 
-static int raid6_reconfig(mddev_t *mddev, int new_layout, int new_chunk)
+static int raid6_check_reshape(mddev_t *mddev)
 {
-        if (new_layout >= 0 && !algorithm_valid_raid6(new_layout))
+        int new_chunk = mddev->new_chunk_sectors;
+
+        if (mddev->new_layout >= 0 && !algorithm_valid_raid6(mddev->new_layout))
                 return -EINVAL;
         if (new_chunk > 0) {
-                if (new_chunk & (new_chunk-1))
-                        /* not a power of 2 */
+                if (!is_power_of_2(new_chunk))
                         return -EINVAL;
-                if (new_chunk < PAGE_SIZE)
+                if (new_chunk < (PAGE_SIZE >> 9))
                         return -EINVAL;
-                if (mddev->array_sectors & ((new_chunk>>9)-1))
+                if (mddev->array_sectors & (new_chunk-1))
                         /* not factor of array size */
                         return -EINVAL;
         }
 
         /* They look valid */
-
-        if (new_layout >= 0)
-                mddev->new_layout = new_layout;
-        if (new_chunk > 0)
-                mddev->new_chunk = new_chunk;
-
-        return 0;
+        return check_reshape(mddev);
 }
 
 static void *raid5_takeover(mddev_t *mddev)
@@ -5570,8 +5581,6 @@ static void *raid5_takeover(mddev_t *mddev)
          *  raid1 - if there are two drives.  We need to know the chunk size
          *  raid4 - trivial - just use a raid4 layout.
          *  raid6 - Providing it is a *_6 layout
-         *
-         * For now, just do raid1
          */
 
         if (mddev->level == 1)
@@ -5653,12 +5662,11 @@ static struct mdk_personality raid6_personality =
         .sync_request   = sync_request,
         .resize         = raid5_resize,
         .size           = raid5_size,
-        .check_reshape  = raid5_check_reshape,
+        .check_reshape  = raid6_check_reshape,
         .start_reshape  = raid5_start_reshape,
         .finish_reshape = raid5_finish_reshape,
         .quiesce        = raid5_quiesce,
         .takeover       = raid6_takeover,
-        .reconfig       = raid6_reconfig,
 };
 static struct mdk_personality raid5_personality =
 {
@@ -5681,7 +5689,6 @@ static struct mdk_personality raid5_personality =
         .finish_reshape = raid5_finish_reshape,
         .quiesce        = raid5_quiesce,
         .takeover       = raid5_takeover,
-        .reconfig       = raid5_reconfig,
 };
 
 static struct mdk_personality raid4_personality =