10 files changed, 58 insertions, 23 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 49da55c..8c2a000 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 89f73ca..f84c080 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 a002dd8..86df8b2 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 986b875..bc04518 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 5404b22..5c95ccb 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 1e586bb..0a309dc 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 3535c23..d5b5fb3 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 f4622dd..d9587df 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 d7a8468..0cd9672 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 43709fa..ac5e8b5 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);