md: fix a potential deadlock of raid5/raid10 reshape

[sfrench/cifs-2.6.git] / drivers / md / raid5.c

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 98ce4272ace9631045f6e00cf3fd7ea8f96b8d77..b5d2601483e34fa97fc8cfb7faeff6f014c0e035 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2196,15 +2196,16 @@ static int grow_one_stripe(struct r5conf *conf, gfp_t gfp)
 static int grow_stripes(struct r5conf *conf, int num)
 {
        struct kmem_cache *sc;
+       size_t namelen = sizeof(conf->cache_name[0]);
        int devs = max(conf->raid_disks, conf->previous_raid_disks);
 
        if (conf->mddev->gendisk)
-               sprintf(conf->cache_name[0],
+               snprintf(conf->cache_name[0], namelen,
                        "raid%d-%s", conf->level, mdname(conf->mddev));
        else
-               sprintf(conf->cache_name[0],
+               snprintf(conf->cache_name[0], namelen,
                        "raid%d-%p", conf->level, conf->mddev);
-       sprintf(conf->cache_name[1], "%s-alt", conf->cache_name[0]);
+       snprintf(conf->cache_name[1], namelen, "%.27s-alt", conf->cache_name[0]);
 
        conf->active_name = 0;
        sc = kmem_cache_create(conf->cache_name[conf->active_name],
@@ -5563,7 +5564,7 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
        bool do_flush = false;
 
        if (unlikely(bi->bi_opf & REQ_PREFLUSH)) {
-               int ret = r5l_handle_flush_request(conf->log, bi);
+               int ret = log_handle_flush_request(conf, bi);
 
                if (ret == 0)
                        return true;
@@ -6168,7 +6169,7 @@ static int handle_active_stripes(struct r5conf *conf, int group,
                                break;
                if (i == NR_STRIPE_HASH_LOCKS) {
                        spin_unlock_irq(&conf->device_lock);
-                       r5l_flush_stripe_to_raid(conf->log);
+                       log_flush_stripe_to_raid(conf);
                        spin_lock_irq(&conf->device_lock);
                        return batch_size;
                }
@@ -6764,9 +6765,7 @@ static void free_conf(struct r5conf *conf)
 
        log_exit(conf);
 
-       if (conf->shrinker.nr_deferred)
-               unregister_shrinker(&conf->shrinker);
-
+       unregister_shrinker(&conf->shrinker);
        free_thread_groups(conf);
        shrink_stripes(conf);
        raid5_free_percpu(conf);
@@ -8001,13 +8000,7 @@ static void raid5_finish_reshape(struct mddev *mddev)
 
        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
 
-               if (mddev->delta_disks > 0) {
-                       md_set_array_sectors(mddev, raid5_size(mddev, 0, 0));
-                       if (mddev->queue) {
-                               set_capacity(mddev->gendisk, mddev->array_sectors);
-                               revalidate_disk(mddev->gendisk);
-                       }
-               } else {
+               if (mddev->delta_disks <= 0) {
                        int d;
                        spin_lock_irq(&conf->device_lock);
                        mddev->degraded = raid5_calc_degraded(conf);
@@ -8060,7 +8053,7 @@ static void raid5_quiesce(struct mddev *mddev, int quiesce)
                wake_up(&conf->wait_for_overlap);
                unlock_all_device_hash_locks_irq(conf);
        }
-       r5l_quiesce(conf->log, quiesce);
+       log_quiesce(conf, quiesce);
 }
 
 static void *raid45_takeover_raid0(struct mddev *mddev, int level)
@@ -8364,6 +8357,13 @@ static int raid5_change_consistency_policy(struct mddev *mddev, const char *buf)
        return err;
 }
 
+static int raid5_start(struct mddev *mddev)
+{
+       struct r5conf *conf = mddev->private;
+
+       return r5l_start(conf->log);
+}
+
 static struct md_personality raid6_personality =
 {
        .name           = "raid6",
@@ -8371,6 +8371,7 @@ static struct md_personality raid6_personality =
        .owner          = THIS_MODULE,
        .make_request   = raid5_make_request,
        .run            = raid5_run,
+       .start          = raid5_start,
        .free           = raid5_free,
        .status         = raid5_status,
        .error_handler  = raid5_error,
@@ -8395,6 +8396,7 @@ static struct md_personality raid5_personality =
        .owner          = THIS_MODULE,
        .make_request   = raid5_make_request,
        .run            = raid5_run,
+       .start          = raid5_start,
        .free           = raid5_free,
        .status         = raid5_status,
        .error_handler  = raid5_error,
@@ -8420,6 +8422,7 @@ static struct md_personality raid4_personality =
        .owner          = THIS_MODULE,
        .make_request   = raid5_make_request,
        .run            = raid5_run,
+       .start          = raid5_start,
        .free           = raid5_free,
        .status         = raid5_status,
        .error_handler  = raid5_error,