10 files changed, 58 insertions, 23 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 49da55c1528a..8c2a000cf3f5 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1698,6 +1698,8 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         }
 
         ti->num_flush_requests = 1;
+        ti->discard_zeroes_data_unsupported = 1;
+
         return 0;
 
 bad:
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index 89f73ca22cfa..f84c08029b21 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -81,8 +81,10 @@ static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
                  * corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>
                  */
                 if (!strcasecmp(arg_name, "corrupt_bio_byte")) {
-                        if (!argc)
+                        if (!argc) {
                                 ti->error = "Feature corrupt_bio_byte requires parameters";
+                                return -EINVAL;
+                        }
 
                         r = dm_read_arg(_args + 1, as, &fc->corrupt_bio_byte, &ti->error);
                         if (r)
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index a002dd85db1e..86df8b2cf927 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -449,7 +449,7 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
                                 rs->ti->error = "write_mostly option is only valid for RAID1";
                                 return -EINVAL;
                         }
-                        if (value > rs->md.raid_disks) {
+                        if (value >= rs->md.raid_disks) {
                                 rs->ti->error = "Invalid write_mostly drive index given";
                                 return -EINVAL;
                         }
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 986b8754bb08..bc04518e9d8b 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1238,14 +1238,15 @@ static void dm_table_set_integrity(struct dm_table *t)
                 return;
 
         template_disk = dm_table_get_integrity_disk(t, true);
-        if (!template_disk &&
-            blk_integrity_is_initialized(dm_disk(t->md))) {
+        if (template_disk)
+                blk_integrity_register(dm_disk(t->md),
+                                       blk_get_integrity(template_disk));
+        else if (blk_integrity_is_initialized(dm_disk(t->md)))
                 DMWARN("%s: device no longer has a valid integrity profile",
                        dm_device_name(t->md));
-                return;
-        }
-        blk_integrity_register(dm_disk(t->md),
-                               blk_get_integrity(template_disk));
+        else
+                DMWARN("%s: unable to establish an integrity profile",
+                       dm_device_name(t->md));
 }
 
 static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
@@ -1282,6 +1283,22 @@ static bool dm_table_supports_flush(struct dm_table *t, unsigned flush)
         return 0;
 }
 
+static bool dm_table_discard_zeroes_data(struct dm_table *t)
+{
+        struct dm_target *ti;
+        unsigned i = 0;
+
+        /* Ensure that all targets supports discard_zeroes_data. */
+        while (i < dm_table_get_num_targets(t)) {
+                ti = dm_table_get_target(t, i++);
+
+                if (ti->discard_zeroes_data_unsupported)
+                        return 0;
+        }
+
+        return 1;
+}
+
 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
                                struct queue_limits *limits)
 {
@@ -1304,6 +1321,9 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
         }
         blk_queue_flush(q, flush);
 
+        if (!dm_table_discard_zeroes_data(t))
+                q->limits.discard_zeroes_data = 0;
+
         dm_table_set_integrity(t);
 
         /*
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 5404b2295820..5c95ccb59500 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -61,6 +61,11 @@
 static void autostart_arrays(int part);
 #endif
 
+/* pers_list is a list of registered personalities protected
+ * by pers_lock.
+ * pers_lock does extra service to protect accesses to
+ * mddev->thread when the mutex cannot be held.
+ */
 static LIST_HEAD(pers_list);
 static DEFINE_SPINLOCK(pers_lock);
 
@@ -739,7 +744,12 @@ static void mddev_unlock(mddev_t * mddev)
         } else
                 mutex_unlock(&mddev->reconfig_mutex);
 
+        /* was we've dropped the mutex we need a spinlock to
+         * make sur the thread doesn't disappear
+         */
+        spin_lock(&pers_lock);
         md_wakeup_thread(mddev->thread);
+        spin_unlock(&pers_lock);
 }
 
 static mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
@@ -6429,11 +6439,18 @@ mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
         return thread;
 }
 
-void md_unregister_thread(mdk_thread_t *thread)
+void md_unregister_thread(mdk_thread_t **threadp)
 {
+        mdk_thread_t *thread = *threadp;
         if (!thread)
                 return;
         dprintk("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
+        /* Locking ensures that mddev_unlock does not wake_up a
+         * non-existent thread
+         */
+        spin_lock(&pers_lock);
+        *threadp = NULL;
+        spin_unlock(&pers_lock);
 
         kthread_stop(thread->tsk);
         kfree(thread);
@@ -7340,8 +7357,7 @@ static void reap_sync_thread(mddev_t *mddev)
         mdk_rdev_t *rdev;
 
         /* resync has finished, collect result */
-        md_unregister_thread(mddev->sync_thread);
-        mddev->sync_thread = NULL;
+        md_unregister_thread(&mddev->sync_thread);
         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
             !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
                 /* success...*/
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 1e586bb4452e..0a309dc29b45 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -560,7 +560,7 @@ extern int register_md_personality(struct mdk_personality *p);
 extern int unregister_md_personality(struct mdk_personality *p);
 extern mdk_thread_t * md_register_thread(void (*run) (mddev_t *mddev),
                                 mddev_t *mddev, const char *name);
-extern void md_unregister_thread(mdk_thread_t *thread);
+extern void md_unregister_thread(mdk_thread_t **threadp);
 extern void md_wakeup_thread(mdk_thread_t *thread);
 extern void md_check_recovery(mddev_t *mddev);
 extern void md_write_start(mddev_t *mddev, struct bio *bi);
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 3535c23af288..d5b5fb300171 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -514,8 +514,7 @@ static int multipath_stop (mddev_t *mddev)
 {
         multipath_conf_t *conf = mddev->private;
 
-        md_unregister_thread(mddev->thread);
-        mddev->thread = NULL;
+        md_unregister_thread(&mddev->thread);
         blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
         mempool_destroy(conf->pool);
         kfree(conf->multipaths);
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index f4622dd8fc59..d9587dffe533 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2562,8 +2562,7 @@ static int stop(mddev_t *mddev)
         raise_barrier(conf);
         lower_barrier(conf);
 
-        md_unregister_thread(mddev->thread);
-        mddev->thread = NULL;
+        md_unregister_thread(&mddev->thread);
         if (conf->r1bio_pool)
                 mempool_destroy(conf->r1bio_pool);
         kfree(conf->mirrors);
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index d7a8468ddeab..0cd9672cf9cb 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2955,7 +2955,7 @@ static int run(mddev_t *mddev)
         return 0;
 
 out_free_conf:
-        md_unregister_thread(mddev->thread);
+        md_unregister_thread(&mddev->thread);
         if (conf->r10bio_pool)
                 mempool_destroy(conf->r10bio_pool);
         safe_put_page(conf->tmppage);
@@ -2973,8 +2973,7 @@ static int stop(mddev_t *mddev)
         raise_barrier(conf, 0);
         lower_barrier(conf);
 
-        md_unregister_thread(mddev->thread);
-        mddev->thread = NULL;
+        md_unregister_thread(&mddev->thread);
         blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
         if (conf->r10bio_pool)
                 mempool_destroy(conf->r10bio_pool);
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 43709fa6b6df..ac5e8b57e50f 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4941,8 +4941,7 @@ static int run(mddev_t *mddev)
 
         return 0;
 abort:
-        md_unregister_thread(mddev->thread);
-        mddev->thread = NULL;
+        md_unregister_thread(&mddev->thread);
         if (conf) {
                 print_raid5_conf(conf);
                 free_conf(conf);
@@ -4956,8 +4955,7 @@ static int stop(mddev_t *mddev)
 {
         raid5_conf_t *conf = mddev->private;
 
-        md_unregister_thread(mddev->thread);
-        mddev->thread = NULL;
+        md_unregister_thread(&mddev->thread);
         if (mddev->queue)
                 mddev->queue->backing_dev_info.congested_fn = NULL;
         free_conf(conf);