1 files changed, 20 insertions, 47 deletions

diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 64713b77df1c..fa7d577f3d12 100644
--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -34,7 +34,7 @@ static inline struct dev_info *which_dev(struct mddev *mddev, sector_t sector)
 
         lo = 0;
         hi = mddev->raid_disks - 1;
-        conf = rcu_dereference(mddev->private);
+        conf = mddev->private;
 
         /*
          * Binary Search
@@ -60,18 +60,16 @@ static inline struct dev_info *which_dev(struct mddev *mddev, sector_t sector)
  *
  *      Return amount of bytes we can take at this offset
  */
-static int linear_mergeable_bvec(struct request_queue *q,
+static int linear_mergeable_bvec(struct mddev *mddev,
                                  struct bvec_merge_data *bvm,
                                  struct bio_vec *biovec)
 {
-        struct mddev *mddev = q->queuedata;
         struct dev_info *dev0;
         unsigned long maxsectors, bio_sectors = bvm->bi_size >> 9;
         sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
         int maxbytes = biovec->bv_len;
         struct request_queue *subq;
 
-        rcu_read_lock();
         dev0 = which_dev(mddev, sector);
         maxsectors = dev0->end_sector - sector;
         subq = bdev_get_queue(dev0->rdev->bdev);
@@ -81,7 +79,6 @@ static int linear_mergeable_bvec(struct request_queue *q,
                 maxbytes = min(maxbytes, subq->merge_bvec_fn(subq, bvm,
                                                              biovec));
         }
-        rcu_read_unlock();
 
         if (maxsectors < bio_sectors)
                 maxsectors = 0;
@@ -97,24 +94,18 @@ static int linear_mergeable_bvec(struct request_queue *q,
                 return maxsectors << 9;
 }
 
-static int linear_congested(void *data, int bits)
+static int linear_congested(struct mddev *mddev, int bits)
 {
-        struct mddev *mddev = data;
         struct linear_conf *conf;
         int i, ret = 0;
 
-        if (mddev_congested(mddev, bits))
-                return 1;
-
-        rcu_read_lock();
-        conf = rcu_dereference(mddev->private);
+        conf = mddev->private;
 
         for (i = 0; i < mddev->raid_disks && !ret ; i++) {
                 struct request_queue *q = bdev_get_queue(conf->disks[i].rdev->bdev);
                 ret |= bdi_congested(&q->backing_dev_info, bits);
         }
 
-        rcu_read_unlock();
         return ret;
 }
 
@@ -123,12 +114,10 @@ static sector_t linear_size(struct mddev *mddev, sector_t sectors, int raid_disk
         struct linear_conf *conf;
         sector_t array_sectors;
 
-        rcu_read_lock();
-        conf = rcu_dereference(mddev->private);
+        conf = mddev->private;
         WARN_ONCE(sectors || raid_disks,
                   "%s does not support generic reshape\n", __func__);
         array_sectors = conf->array_sectors;
-        rcu_read_unlock();
 
         return array_sectors;
 }
@@ -217,10 +206,6 @@ static int linear_run (struct mddev *mddev)
         mddev->private = conf;
         md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
 
-        blk_queue_merge_bvec(mddev->queue, linear_mergeable_bvec);
-        mddev->queue->backing_dev_info.congested_fn = linear_congested;
-        mddev->queue->backing_dev_info.congested_data = mddev;
-
         ret =  md_integrity_register(mddev);
         if (ret) {
                 kfree(conf);
@@ -252,38 +237,23 @@ static int linear_add(struct mddev *mddev, struct md_rdev *rdev)
         if (!newconf)
                 return -ENOMEM;
 
-        oldconf = rcu_dereference_protected(mddev->private,
-                                            lockdep_is_held(
-                                                    &mddev->reconfig_mutex));
+        mddev_suspend(mddev);
+        oldconf = mddev->private;
         mddev->raid_disks++;
-        rcu_assign_pointer(mddev->private, newconf);
+        mddev->private = newconf;
         md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
         set_capacity(mddev->gendisk, mddev->array_sectors);
+        mddev_resume(mddev);
         revalidate_disk(mddev->gendisk);
-        kfree_rcu(oldconf, rcu);
+        kfree(oldconf);
         return 0;
 }
 
-static int linear_stop (struct mddev *mddev)
+static void linear_free(struct mddev *mddev, void *priv)
 {
-        struct linear_conf *conf =
-                rcu_dereference_protected(mddev->private,
-                                          lockdep_is_held(
-                                                  &mddev->reconfig_mutex));
+        struct linear_conf *conf = priv;
 
-        /*
-         * We do not require rcu protection here since
-         * we hold reconfig_mutex for both linear_add and
-         * linear_stop, so they cannot race.
-         * We should make sure any old 'conf's are properly
-         * freed though.
-         */
-        rcu_barrier();
-        blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
         kfree(conf);
-        mddev->private = NULL;
-
-        return 0;
 }
 
 static void linear_make_request(struct mddev *mddev, struct bio *bio)
@@ -299,16 +269,12 @@ static void linear_make_request(struct mddev *mddev, struct bio *bio)
         }
 
         do {
-                rcu_read_lock();
-
                 tmp_dev = which_dev(mddev, bio->bi_iter.bi_sector);
                 start_sector = tmp_dev->end_sector - tmp_dev->rdev->sectors;
                 end_sector = tmp_dev->end_sector;
                 data_offset = tmp_dev->rdev->data_offset;
                 bio->bi_bdev = tmp_dev->rdev->bdev;
 
-                rcu_read_unlock();
-
                 if (unlikely(bio->bi_iter.bi_sector >= end_sector ||
                              bio->bi_iter.bi_sector < start_sector))
                         goto out_of_bounds;
@@ -355,6 +321,10 @@ static void linear_status (struct seq_file *seq, struct mddev *mddev)
         seq_printf(seq, " %dk rounding", mddev->chunk_sectors / 2);
 }
 
+static void linear_quiesce(struct mddev *mddev, int state)
+{
+}
+
 static struct md_personality linear_personality =
 {
         .name           = "linear",
@@ -362,10 +332,13 @@ static struct md_personality linear_personality =
         .owner          = THIS_MODULE,
         .make_request   = linear_make_request,
         .run            = linear_run,
-        .stop           = linear_stop,
+        .free           = linear_free,
         .status         = linear_status,
         .hot_add_disk   = linear_add,
         .size           = linear_size,
+        .quiesce        = linear_quiesce,
+        .congested      = linear_congested,
+        .mergeable_bvec = linear_mergeable_bvec,
 };
 
 static int __init linear_init (void)