[RFC 00/12] drbd: part 16 of adding multiple volume support to drbd

[RFC 00/12] drbd: part 16 of adding multiple volume support to drbd

[Philipp Reisner]

This the first request for review of drbd-8.4. The complete set has 
453 patches. This is the sixteenth installment containing 12 patches.

The whole set is available here:
  git://git.drbd.org/linux-2.6-drbd.git for-jens

and is jens_for-3.2_drivers...for-jens
and this part is 80c99c9^...330bea2

This patch series contains:
 * Reference counting for mdev objects
 * RCU for the connection list
 * Removal of rw_semaphore drbd_cfg_rwsem
 * Cleanups: Better names for some constants and variables

[PATCH 01/12] drbd: Refcounting for mdev objects

[Philipp Reisner]

Preparing removal of drbd_cfg_rwsem

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_int.h      |    3 ++-
 drivers/block/drbd/drbd_main.c     |   27 +++++++++++++++++----------
 drivers/block/drbd/drbd_nl.c       |    8 ++++++--
 drivers/block/drbd/drbd_receiver.c |   12 ++++++------
 4 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 3f377e2..8bc604e 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -867,6 +867,7 @@ struct drbd_tconn {			/* is a resource from the config file */
 struct drbd_conf {
 	struct drbd_tconn *tconn;
 	int vnr;			/* volume number within the connection */
+	struct kref kref;
 
 	/* things that are stored as / read from meta data on disk */
 	unsigned long flags;
@@ -1373,7 +1374,7 @@ extern rwlock_t global_state_lock;
 
 extern int conn_lowest_minor(struct drbd_tconn *tconn);
 enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor, int vnr);
-extern void drbd_delete_device(struct drbd_conf *mdev);
+extern void drbd_minor_destroy(struct kref *kref);
 
 struct drbd_tconn *conn_create(const char *name);
 extern void conn_destroy(struct kref *kref);
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 3560581..9e4c487 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2052,7 +2052,6 @@ void drbd_init_set_defaults(struct drbd_conf *mdev)
 	init_waitqueue_head(&mdev->al_wait);
 	init_waitqueue_head(&mdev->seq_wait);
 
-	/* mdev->tconn->agreed_pro_version gets initialized in drbd_connect() */
 	mdev->write_ordering = WO_bdev_flush;
 	mdev->resync_wenr = LC_FREE;
 	mdev->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
@@ -2272,21 +2271,16 @@ static void drbd_release_all_peer_reqs(struct drbd_conf *mdev)
 }
 
 /* caution. no locking. */
-void drbd_delete_device(struct drbd_conf *mdev)
+void drbd_minor_destroy(struct kref *kref)
 {
+	struct drbd_conf *mdev = container_of(kref, struct drbd_conf, kref);
 	struct drbd_tconn *tconn = mdev->tconn;
 
-	idr_remove(&mdev->tconn->volumes, mdev->vnr);
-	idr_remove(&minors, mdev_to_minor(mdev));
-	synchronize_rcu();
-
 	/* paranoia asserts */
 	D_ASSERT(mdev->open_cnt == 0);
 	D_ASSERT(list_empty(&mdev->tconn->data.work.q));
 	/* end paranoia asserts */
 
-	del_gendisk(mdev->vdisk);
-
 	/* cleanup stuff that may have been allocated during
 	 * device (re-)configuration or state changes */
 
@@ -2320,6 +2314,7 @@ static void drbd_cleanup(void)
 {
 	unsigned int i;
 	struct drbd_conf *mdev;
+	struct drbd_tconn *tconn, *tmp;
 
 	unregister_reboot_notifier(&drbd_notifier);
 
@@ -2337,8 +2332,19 @@ static void drbd_cleanup(void)
 	drbd_genl_unregister();
 
 	down_write(&drbd_cfg_rwsem);
-	idr_for_each_entry(&minors, mdev, i)
-		drbd_delete_device(mdev);
+	idr_for_each_entry(&minors, mdev, i) {
+		idr_remove(&minors, mdev_to_minor(mdev));
+		idr_remove(&mdev->tconn->volumes, mdev->vnr);
+		del_gendisk(mdev->vdisk);
+		synchronize_rcu();
+		kref_put(&mdev->kref, &drbd_minor_destroy);
+	}
+
+	list_for_each_entry_safe(tconn, tmp, &drbd_tconns, all_tconn) {
+		list_del(&tconn->all_tconn);
+		synchronize_rcu();
+		kref_put(&tconn->kref, &conn_destroy);
+	}
 	up_write(&drbd_cfg_rwsem);
 
 	drbd_destroy_mempools();
@@ -2625,6 +2631,7 @@ enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor,
 		goto out_idr_remove_vol;
 	}
 	add_disk(disk);
+	kref_init(&mdev->kref); /* one ref for both idrs and the the add_disk */
 
 	/* inherit the connection state */
 	mdev->state.conn = tconn->cstate;
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index ce5d519..3c55be5 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1087,7 +1087,7 @@ static void conn_reconfig_done(struct drbd_tconn *tconn)
 	spin_unlock_irq(&tconn->req_lock);
 	if (stop_threads) {
 		/* asender is implicitly stopped by receiver
-		 * in drbd_disconnect() */
+		 * in conn_disconnect() */
 		drbd_thread_stop(&tconn->receiver);
 		drbd_thread_stop(&tconn->worker);
 	}
@@ -3079,7 +3079,11 @@ static enum drbd_ret_code adm_delete_minor(struct drbd_conf *mdev)
 	     * we may want to delete a minor from a live replication group.
 	     */
 	    mdev->state.role == R_SECONDARY) {
-		drbd_delete_device(mdev);
+		idr_remove(&mdev->tconn->volumes, mdev->vnr);
+		idr_remove(&minors, mdev_to_minor(mdev));
+		del_gendisk(mdev->vdisk);
+		synchronize_rcu();
+		kref_put(&mdev->kref, &drbd_minor_destroy);
 		return NO_ERROR;
 	} else
 		return ERR_MINOR_CONFIGURED;
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index b4858bb..7156e53 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -844,7 +844,7 @@ int drbd_connected(int vnr, void *p, void *data)
  *     no point in trying again, please go standalone.
  *  -2 We do not have a network config...
  */
-static int drbd_connect(struct drbd_tconn *tconn)
+static int conn_connect(struct drbd_tconn *tconn)
 {
 	struct socket *sock, *msock;
 	struct net_conf *nc;
@@ -878,7 +878,7 @@ static int drbd_connect(struct drbd_tconn *tconn)
 				tconn->meta.socket = s;
 				send_first_packet(tconn, &tconn->meta, P_INITIAL_META);
 			} else {
-				conn_err(tconn, "Logic error in drbd_connect()\n");
+				conn_err(tconn, "Logic error in conn_connect()\n");
 				goto out_release_sockets;
 			}
 		}
@@ -4240,7 +4240,7 @@ void conn_flush_workqueue(struct drbd_tconn *tconn)
 	wait_for_completion(&barr.done);
 }
 
-static void drbd_disconnect(struct drbd_tconn *tconn)
+static void conn_disconnect(struct drbd_tconn *tconn)
 {
 	enum drbd_conns oc;
 	int rv = SS_UNKNOWN_ERROR;
@@ -4636,9 +4636,9 @@ int drbdd_init(struct drbd_thread *thi)
 	conn_info(tconn, "receiver (re)started\n");
 
 	do {
-		h = drbd_connect(tconn);
+		h = conn_connect(tconn);
 		if (h == 0) {
-			drbd_disconnect(tconn);
+			conn_disconnect(tconn);
 			schedule_timeout_interruptible(HZ);
 		}
 		if (h == -1) {
@@ -4650,7 +4650,7 @@ int drbdd_init(struct drbd_thread *thi)
 	if (h > 0)
 		drbdd(tconn);
 
-	drbd_disconnect(tconn);
+	conn_disconnect(tconn);
 
 	conn_info(tconn, "receiver terminated\n");
 	return 0;
-- 
1.7.4.1

[PATCH 02/12] drbd: Use RCU for the drbd_tconns list

[Philipp Reisner]

Preparing removal of drbd_cfg_rwsem

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_main.c |    7 ++++---
 drivers/block/drbd/drbd_nl.c   |   12 +++++++-----
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 9e4c487..c229448 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2341,7 +2341,7 @@ static void drbd_cleanup(void)
 	}
 
 	list_for_each_entry_safe(tconn, tmp, &drbd_tconns, all_tconn) {
-		list_del(&tconn->all_tconn);
+		list_del_rcu(&tconn->all_tconn);
 		synchronize_rcu();
 		kref_put(&tconn->kref, &conn_destroy);
 	}
@@ -2409,7 +2409,7 @@ struct drbd_tconn *conn_get_by_name(const char *name)
 		return NULL;
 
 	down_read(&drbd_cfg_rwsem);
-	list_for_each_entry(tconn, &drbd_tconns, all_tconn) {
+	list_for_each_entry_rcu(tconn, &drbd_tconns, all_tconn) {
 		if (!strcmp(tconn->name, name)) {
 			kref_get(&tconn->kref);
 			goto found;
@@ -2459,6 +2459,7 @@ void conn_free_crypto(struct drbd_tconn *tconn)
 	tconn->int_dig_vv = NULL;
 }
 
+/* caller must be under genl_lock() */
 struct drbd_tconn *conn_create(const char *name)
 {
 	struct drbd_tconn *tconn;
@@ -2503,7 +2504,7 @@ struct drbd_tconn *conn_create(const char *name)
 
 	down_write(&drbd_cfg_rwsem);
 	kref_init(&tconn->kref);
-	list_add_tail(&tconn->all_tconn, &drbd_tconns);
+	list_add_tail_rcu(&tconn->all_tconn, &drbd_tconns);
 	up_write(&drbd_cfg_rwsem);
 
 	return tconn;
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 3c55be5..49f3b8d 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -2719,7 +2719,7 @@ int get_one_status(struct sk_buff *skb, struct netlink_callback *cb)
 	/* synchronize with conn_create()/conn_destroy() */
 	down_read(&drbd_cfg_rwsem);
 	/* revalidate iterator position */
-	list_for_each_entry(tmp, &drbd_tconns, all_tconn) {
+	list_for_each_entry_rcu(tmp, &drbd_tconns, all_tconn) {
 		if (pos == NULL) {
 			/* first iteration */
 			pos = tmp;
@@ -2737,8 +2737,8 @@ next_tconn:
 		if (!mdev) {
 			/* No more volumes to dump on this tconn.
 			 * Advance tconn iterator. */
-			pos = list_entry(tconn->all_tconn.next,
-					struct drbd_tconn, all_tconn);
+			pos = list_entry_rcu(tconn->all_tconn.next,
+					     struct drbd_tconn, all_tconn);
 			/* Did we dump any volume on this tconn yet? */
 			if (volume != 0) {
 				/* If we reached the end of the list,
@@ -3176,7 +3176,8 @@ int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
 
 	/* delete connection */
 	if (conn_lowest_minor(adm_ctx.tconn) < 0) {
-		list_del(&adm_ctx.tconn->all_tconn);
+		list_del_rcu(&adm_ctx.tconn->all_tconn);
+		synchronize_rcu();
 		kref_put(&adm_ctx.tconn->kref, &conn_destroy);
 
 		retcode = NO_ERROR;
@@ -3206,7 +3207,8 @@ int drbd_adm_delete_connection(struct sk_buff *skb, struct genl_info *info)
 
 	down_write(&drbd_cfg_rwsem);
 	if (conn_lowest_minor(adm_ctx.tconn) < 0) {
-		list_del(&adm_ctx.tconn->all_tconn);
+		list_del_rcu(&adm_ctx.tconn->all_tconn);
+		synchronize_rcu();
 		kref_put(&adm_ctx.tconn->kref, &conn_destroy);
 
 		retcode = NO_ERROR;
-- 
1.7.4.1

[PATCH 03/12] drbd: Removing drbd_cfg_rwsem

[Philipp Reisner]

 * Updates to all configuration items is done under genl_lock().
   Including removal of mdevs or tconns.
 * All read non sleeping read sides are protected by rcu
 * All sleeping read sides keep reference counts to keep the
   objects alive

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_int.h      |    9 ++---
 drivers/block/drbd/drbd_main.c     |   20 ++++--------
 drivers/block/drbd/drbd_nl.c       |   43 +++++++++----------------
 drivers/block/drbd/drbd_proc.c     |    6 +--
 drivers/block/drbd/drbd_receiver.c |   61 +++++++++++++++++++++++-------------
 drivers/block/drbd/drbd_worker.c   |    8 +++-
 6 files changed, 72 insertions(+), 75 deletions(-)

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 8bc604e..56b190c 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -169,11 +169,8 @@ drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) {
 #define DRBD_MD_MAGIC (DRBD_MAGIC+4)
 
 extern struct ratelimit_state drbd_ratelimit_state;
-extern struct idr minors;
-extern struct list_head drbd_tconns;
-extern struct rw_semaphore drbd_cfg_rwsem;
-/* drbd_cfg_rwsem protects: drbd_tconns list, minors idr, tconn->volumes idr 
-   note: non sleeping iterations over the idrs are protoected by RCU */
+extern struct idr minors; /* RCU, updates: genl_lock() */
+extern struct list_head drbd_tconns; /* RCU, updates: genl_lock() */
 
 /* on the wire */
 enum drbd_packet {
@@ -1477,7 +1474,7 @@ extern struct page *drbd_alloc_pages(struct drbd_conf *, unsigned int, bool);
 extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled);
 extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed);
 extern void conn_flush_workqueue(struct drbd_tconn *tconn);
-extern int drbd_connected(int vnr, void *p, void *data);
+extern int drbd_connected(struct drbd_conf *mdev);
 static inline void drbd_flush_workqueue(struct drbd_conf *mdev)
 {
 	conn_flush_workqueue(mdev->tconn);
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index c229448..dd5b56c 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -120,7 +120,6 @@ module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0
  */
 struct idr minors;
 struct list_head drbd_tconns;  /* list of struct drbd_tconn */
-DECLARE_RWSEM(drbd_cfg_rwsem);
 
 struct kmem_cache *drbd_request_cache;
 struct kmem_cache *drbd_ee_cache;	/* peer requests */
@@ -2331,21 +2330,20 @@ static void drbd_cleanup(void)
 
 	drbd_genl_unregister();
 
-	down_write(&drbd_cfg_rwsem);
 	idr_for_each_entry(&minors, mdev, i) {
 		idr_remove(&minors, mdev_to_minor(mdev));
 		idr_remove(&mdev->tconn->volumes, mdev->vnr);
 		del_gendisk(mdev->vdisk);
-		synchronize_rcu();
+		/* synchronize_rcu(); No other threads running at this point */
 		kref_put(&mdev->kref, &drbd_minor_destroy);
 	}
 
+	/* not _rcu since, no other updater anymore. Genl already unregistered */
 	list_for_each_entry_safe(tconn, tmp, &drbd_tconns, all_tconn) {
-		list_del_rcu(&tconn->all_tconn);
-		synchronize_rcu();
+		list_del(&tconn->all_tconn); /* not _rcu no proc, not other threads */
+		/* synchronize_rcu(); */
 		kref_put(&tconn->kref, &conn_destroy);
 	}
-	up_write(&drbd_cfg_rwsem);
 
 	drbd_destroy_mempools();
 	unregister_blkdev(DRBD_MAJOR, "drbd");
@@ -2408,7 +2406,7 @@ struct drbd_tconn *conn_get_by_name(const char *name)
 	if (!name || !name[0])
 		return NULL;
 
-	down_read(&drbd_cfg_rwsem);
+	rcu_read_lock();
 	list_for_each_entry_rcu(tconn, &drbd_tconns, all_tconn) {
 		if (!strcmp(tconn->name, name)) {
 			kref_get(&tconn->kref);
@@ -2417,7 +2415,7 @@ struct drbd_tconn *conn_get_by_name(const char *name)
 	}
 	tconn = NULL;
 found:
-	up_read(&drbd_cfg_rwsem);
+	rcu_read_unlock();
 	return tconn;
 }
 
@@ -2502,10 +2500,8 @@ struct drbd_tconn *conn_create(const char *name)
 
 	drbd_set_res_opts_defaults(&tconn->res_opts);
 
-	down_write(&drbd_cfg_rwsem);
 	kref_init(&tconn->kref);
 	list_add_tail_rcu(&tconn->all_tconn, &drbd_tconns);
-	up_write(&drbd_cfg_rwsem);
 
 	return tconn;
 
@@ -2637,7 +2633,7 @@ enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor,
 	/* inherit the connection state */
 	mdev->state.conn = tconn->cstate;
 	if (mdev->state.conn == C_WF_REPORT_PARAMS)
-		drbd_connected(vnr, mdev, tconn);
+		drbd_connected(mdev);
 
 	return NO_ERROR;
 
@@ -2913,12 +2909,10 @@ int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
 	}
 	spin_unlock_irq(&mdev->tconn->req_lock);
 
-	mutex_lock(&mdev->tconn->conf_update);
 	/* This blocks wants to be get removed... */
 	bdev->disk_conf->al_extents = be32_to_cpu(buffer->al_nr_extents);
 	if (bdev->disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
 		bdev->disk_conf->al_extents = DRBD_AL_EXTENTS_DEF;
-	mutex_unlock(&mdev->tconn->conf_update);
 
  err:
 	mutex_unlock(&mdev->md_io_mutex);
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 49f3b8d..70f7dd8 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -370,10 +370,15 @@ static void conn_md_sync(struct drbd_tconn *tconn)
 	struct drbd_conf *mdev;
 	int vnr;
 
-	down_read(&drbd_cfg_rwsem);
-	idr_for_each_entry(&tconn->volumes, mdev, vnr)
+	rcu_read_lock();
+	idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+		kref_get(&mdev->kref);
+		rcu_read_unlock();
 		drbd_md_sync(mdev);
-	up_read(&drbd_cfg_rwsem);
+		kref_put(&mdev->kref, &drbd_minor_destroy);
+		rcu_read_lock();
+	}
+	rcu_read_unlock();
 }
 
 int conn_khelper(struct drbd_tconn *tconn, char *cmd)
@@ -1229,12 +1234,12 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 		rcu_assign_pointer(mdev->rs_plan_s, new_plan);
 	}
 
+	mutex_unlock(&mdev->tconn->conf_update);
 	drbd_md_sync(mdev);
 
 	if (mdev->state.conn >= C_CONNECTED)
 		drbd_send_sync_param(mdev);
 
-	mutex_unlock(&mdev->tconn->conf_update);
 	synchronize_rcu();
 	kfree(old_disk_conf);
 	kfree(old_plan);
@@ -2058,7 +2063,7 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info)
 	new_my_addr = (struct sockaddr *)&new_conf->my_addr;
 	new_peer_addr = (struct sockaddr *)&new_conf->peer_addr;
 
-	/* No need to take drbd_cfg_rwsem here.  All reconfiguration is
+	/* No need for _rcu here. All reconfiguration is
 	 * strictly serialized on genl_lock(). We are protected against
 	 * concurrent reconfiguration/addition/deletion */
 	list_for_each_entry(oconn, &drbd_tconns, all_tconn) {
@@ -2717,7 +2722,7 @@ int get_one_status(struct sk_buff *skb, struct netlink_callback *cb)
 	 */
 
 	/* synchronize with conn_create()/conn_destroy() */
-	down_read(&drbd_cfg_rwsem);
+	rcu_read_lock();
 	/* revalidate iterator position */
 	list_for_each_entry_rcu(tmp, &drbd_tconns, all_tconn) {
 		if (pos == NULL) {
@@ -2785,7 +2790,7 @@ next_tconn:
         }
 
 out:
-	up_read(&drbd_cfg_rwsem);
+	rcu_read_unlock();
 	/* where to start the next iteration */
         cb->args[0] = (long)pos;
         cb->args[1] = (pos == tconn) ? volume + 1 : 0;
@@ -3064,9 +3069,7 @@ int drbd_adm_add_minor(struct sk_buff *skb, struct genl_info *info)
 		goto out;
 	}
 
-	down_write(&drbd_cfg_rwsem);
 	retcode = conn_new_minor(adm_ctx.tconn, dh->minor, adm_ctx.volume);
-	up_write(&drbd_cfg_rwsem);
 out:
 	drbd_adm_finish(info, retcode);
 	return 0;
@@ -3099,9 +3102,7 @@ int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info)
 	if (retcode != NO_ERROR)
 		goto out;
 
-	down_write(&drbd_cfg_rwsem);
 	retcode = adm_delete_minor(adm_ctx.mdev);
-	up_write(&drbd_cfg_rwsem);
 out:
 	drbd_adm_finish(info, retcode);
 	return 0;
@@ -3124,52 +3125,43 @@ int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
 		goto out;
 	}
 
-	down_read(&drbd_cfg_rwsem);
 	/* demote */
 	idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {
 		retcode = drbd_set_role(mdev, R_SECONDARY, 0);
 		if (retcode < SS_SUCCESS) {
 			drbd_msg_put_info("failed to demote");
-			goto out_unlock;
+			goto out;
 		}
 	}
-	up_read(&drbd_cfg_rwsem);
 
-	/* disconnect; may stop the receiver;
-	 * must not hold the drbd_cfg_rwsem */
 	retcode = conn_try_disconnect(adm_ctx.tconn, 0);
 	if (retcode < SS_SUCCESS) {
 		drbd_msg_put_info("failed to disconnect");
 		goto out;
 	}
 
-	down_read(&drbd_cfg_rwsem);
 	/* detach */
 	idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {
 		retcode = adm_detach(mdev);
 		if (retcode < SS_SUCCESS) {
 			drbd_msg_put_info("failed to detach");
-			goto out_unlock;
+			goto out;
 		}
 	}
-	up_read(&drbd_cfg_rwsem);
 
 	/* If we reach this, all volumes (of this tconn) are Secondary,
 	 * Disconnected, Diskless, aka Unconfigured. Make sure all threads have
-	 * actually stopped, state handling only does drbd_thread_stop_nowait().
-	 * This needs to be done without holding drbd_cfg_rwsem. */
+	 * actually stopped, state handling only does drbd_thread_stop_nowait(). */
 	drbd_thread_stop(&adm_ctx.tconn->worker);
 
 	/* Now, nothing can fail anymore */
 
 	/* delete volumes */
-	down_write(&drbd_cfg_rwsem);
 	idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {
 		retcode = adm_delete_minor(mdev);
 		if (retcode != NO_ERROR) {
 			/* "can not happen" */
 			drbd_msg_put_info("failed to delete volume");
-			up_write(&drbd_cfg_rwsem);
 			goto out;
 		}
 	}
@@ -3186,10 +3178,7 @@ int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
 		retcode = ERR_CONN_IN_USE;
 		drbd_msg_put_info("failed to delete connection");
 	}
-	up_write(&drbd_cfg_rwsem);
 	goto out;
-out_unlock:
-	up_read(&drbd_cfg_rwsem);
 out:
 	drbd_adm_finish(info, retcode);
 	return 0;
@@ -3205,7 +3194,6 @@ int drbd_adm_delete_connection(struct sk_buff *skb, struct genl_info *info)
 	if (retcode != NO_ERROR)
 		goto out;
 
-	down_write(&drbd_cfg_rwsem);
 	if (conn_lowest_minor(adm_ctx.tconn) < 0) {
 		list_del_rcu(&adm_ctx.tconn->all_tconn);
 		synchronize_rcu();
@@ -3215,7 +3203,6 @@ int drbd_adm_delete_connection(struct sk_buff *skb, struct genl_info *info)
 	} else {
 		retcode = ERR_CONN_IN_USE;
 	}
-	up_write(&drbd_cfg_rwsem);
 
 	if (retcode == NO_ERROR)
 		drbd_thread_stop(&adm_ctx.tconn->worker);
diff --git a/drivers/block/drbd/drbd_proc.c b/drivers/block/drbd/drbd_proc.c
index 792a71e..6b226cc 100644
--- a/drivers/block/drbd/drbd_proc.c
+++ b/drivers/block/drbd/drbd_proc.c
@@ -229,7 +229,7 @@ static int drbd_seq_show(struct seq_file *seq, void *v)
 	 oos .. known out-of-sync kB
 	*/
 
-	down_read(&drbd_cfg_rwsem);
+	rcu_read_lock();
 	idr_for_each_entry(&minors, mdev, i) {
 		if (prev_i != i - 1)
 			seq_printf(seq, "\n");
@@ -242,10 +242,8 @@ static int drbd_seq_show(struct seq_file *seq, void *v)
 		    mdev->state.role == R_SECONDARY) {
 			seq_printf(seq, "%2d: cs:Unconfigured\n", i);
 		} else {
-			rcu_read_lock();
 			nc = rcu_dereference(mdev->tconn->net_conf);
 			wp = nc ? nc->wire_protocol - DRBD_PROT_A + 'A' : ' ';
-			rcu_read_unlock();
 			seq_printf(seq,
 			   "%2d: cs:%s ro:%s/%s ds:%s/%s %c %c%c%c%c%c%c\n"
 			   "    ns:%u nr:%u dw:%u dr:%u al:%u bm:%u "
@@ -299,7 +297,7 @@ static int drbd_seq_show(struct seq_file *seq, void *v)
 			}
 		}
 	}
-	up_read(&drbd_cfg_rwsem);
+	rcu_read_unlock();
 
 	return 0;
 }
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 7156e53..aa42967 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -63,7 +63,7 @@ enum finish_epoch {
 
 static int drbd_do_features(struct drbd_tconn *tconn);
 static int drbd_do_auth(struct drbd_tconn *tconn);
-static int drbd_disconnected(int vnr, void *p, void *data);
+static int drbd_disconnected(struct drbd_conf *mdev);
 
 static enum finish_epoch drbd_may_finish_epoch(struct drbd_conf *, struct drbd_epoch *, enum epoch_event);
 static int e_end_block(struct drbd_work *, int);
@@ -811,9 +811,8 @@ static int drbd_socket_okay(struct socket **sock)
 }
 /* Gets called if a connection is established, or if a new minor gets created
    in a connection */
-int drbd_connected(int vnr, void *p, void *data)
+int drbd_connected(struct drbd_conf *mdev)
 {
-	struct drbd_conf *mdev = (struct drbd_conf *)p;
 	int err;
 
 	atomic_set(&mdev->packet_seq, 0);
@@ -847,8 +846,9 @@ int drbd_connected(int vnr, void *p, void *data)
 static int conn_connect(struct drbd_tconn *tconn)
 {
 	struct socket *sock, *msock;
+	struct drbd_conf *mdev;
 	struct net_conf *nc;
-	int timeout, try, h, ok;
+	int vnr, timeout, try, h, ok;
 
 	if (conn_request_state(tconn, NS(conn, C_WF_CONNECTION), CS_VERBOSE) < SS_SUCCESS)
 		return -2;
@@ -1001,9 +1001,16 @@ retry:
 	if (drbd_send_protocol(tconn) == -EOPNOTSUPP)
 		return -1;
 
-	down_read(&drbd_cfg_rwsem);
-	h = !idr_for_each(&tconn->volumes, drbd_connected, tconn);
-	up_read(&drbd_cfg_rwsem);
+	rcu_read_lock();
+	idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+		kref_get(&mdev->kref);
+		rcu_read_unlock();
+		drbd_connected(mdev);
+		kref_put(&mdev->kref, &drbd_minor_destroy);
+		rcu_read_lock();
+	}
+	rcu_read_unlock();
+
 	return h;
 
 out_release_sockets:
@@ -4242,8 +4249,9 @@ void conn_flush_workqueue(struct drbd_tconn *tconn)
 
 static void conn_disconnect(struct drbd_tconn *tconn)
 {
+	struct drbd_conf *mdev;
 	enum drbd_conns oc;
-	int rv = SS_UNKNOWN_ERROR;
+	int vnr, rv = SS_UNKNOWN_ERROR;
 
 	if (tconn->cstate == C_STANDALONE)
 		return;
@@ -4252,9 +4260,16 @@ static void conn_disconnect(struct drbd_tconn *tconn)
 	drbd_thread_stop(&tconn->asender);
 	drbd_free_sock(tconn);
 
-	down_read(&drbd_cfg_rwsem);
-	idr_for_each(&tconn->volumes, drbd_disconnected, tconn);
-	up_read(&drbd_cfg_rwsem);
+	rcu_read_lock();
+	idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+		kref_get(&mdev->kref);
+		rcu_read_unlock();
+		drbd_disconnected(mdev);
+		kref_put(&mdev->kref, &drbd_minor_destroy);
+		rcu_read_lock();
+	}
+	rcu_read_unlock();
+
 	conn_info(tconn, "Connection closed\n");
 
 	if (conn_highest_role(tconn) == R_PRIMARY && conn_highest_pdsk(tconn) >= D_UNKNOWN)
@@ -4271,9 +4286,8 @@ static void conn_disconnect(struct drbd_tconn *tconn)
 		conn_request_state(tconn, NS(conn, C_STANDALONE), CS_VERBOSE | CS_HARD);
 }
 
-static int drbd_disconnected(int vnr, void *p, void *data)
+static int drbd_disconnected(struct drbd_conf *mdev)
 {
-	struct drbd_conf *mdev = (struct drbd_conf *)p;
 	enum drbd_fencing_p fp;
 	unsigned int i;
 
@@ -4974,30 +4988,33 @@ static int got_skip(struct drbd_tconn *tconn, struct packet_info *pi)
 static int tconn_finish_peer_reqs(struct drbd_tconn *tconn)
 {
 	struct drbd_conf *mdev;
-	int i, not_empty = 0;
+	int vnr, not_empty = 0;
 
 	do {
 		clear_bit(SIGNAL_ASENDER, &tconn->flags);
 		flush_signals(current);
-		down_read(&drbd_cfg_rwsem);
-		idr_for_each_entry(&tconn->volumes, mdev, i) {
+
+		rcu_read_lock();
+		idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+			kref_get(&mdev->kref);
+			rcu_read_unlock();
 			if (drbd_finish_peer_reqs(mdev)) {
-				up_read(&drbd_cfg_rwsem);
-				return 1; /* error */
+				kref_put(&mdev->kref, &drbd_minor_destroy);
+				return 1;
 			}
+			kref_put(&mdev->kref, &drbd_minor_destroy);
+			rcu_read_lock();
 		}
-		up_read(&drbd_cfg_rwsem);
 		set_bit(SIGNAL_ASENDER, &tconn->flags);
 
 		spin_lock_irq(&tconn->req_lock);
-		rcu_read_lock();
-		idr_for_each_entry(&tconn->volumes, mdev, i) {
+		idr_for_each_entry(&tconn->volumes, mdev, vnr) {
 			not_empty = !list_empty(&mdev->done_ee);
 			if (not_empty)
 				break;
 		}
-		rcu_read_unlock();
 		spin_unlock_irq(&tconn->req_lock);
+		rcu_read_unlock();
 	} while (not_empty);
 
 	return 0;
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index feb12b0..46b5f7f 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -1774,12 +1774,16 @@ int drbd_worker(struct drbd_thread *thi)
 	 */
 	spin_unlock_irq(&tconn->data.work.q_lock);
 
-	down_read(&drbd_cfg_rwsem);
+	rcu_read_lock();
 	idr_for_each_entry(&tconn->volumes, mdev, vnr) {
 		D_ASSERT(mdev->state.disk == D_DISKLESS && mdev->state.conn == C_STANDALONE);
+		kref_get(&mdev->kref);
+		rcu_read_unlock();
 		drbd_mdev_cleanup(mdev);
+		kref_put(&mdev->kref, &drbd_minor_destroy);
+		rcu_read_lock();
 	}
-	up_read(&drbd_cfg_rwsem);
+	rcu_read_unlock();
 
 	return 0;
 }
-- 
1.7.4.1

[PATCH 04/12] drbd: Make broadcast events return NO_ERROR

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

Instead of returning a ret_code outside of the range of enum
drbd_ret_code, use NO_ERROR to indicate success.  This way,
ret_code has the same meaning in all packets.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_nl.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 70f7dd8..caa8ba2 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -3229,7 +3229,7 @@ void drbd_bcast_event(struct drbd_conf *mdev, const struct sib_info *sib)
 	if (!d_out) /* cannot happen, but anyways. */
 		goto nla_put_failure;
 	d_out->minor = mdev_to_minor(mdev);
-	d_out->ret_code = 0;
+	d_out->ret_code = NO_ERROR;
 
 	pr_info("event: minor=%u, conn=%s\n", d_out->minor, mdev->tconn->name);
 
-- 
1.7.4.1

[PATCH 05/12] drbd: Also define the default values of boolean flags in a single place

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 include/linux/drbd_genl.h   |   16 ++++++++--------
 include/linux/drbd_limits.h |   10 ++++++++++
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index 601334b..eba635a 100644
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -124,10 +124,10 @@ GENL_struct(DRBD_NLA_DISK_CONF, 3, disk_conf,
 	__u32_field_def(14,	GENLA_F_MANDATORY,	c_max_rate, DRBD_C_MAX_RATE_DEF)
 	__u32_field_def(15,	GENLA_F_MANDATORY,	c_min_rate, DRBD_C_MIN_RATE_DEF)
 
-	__flg_field_def(16, GENLA_F_MANDATORY,	disk_barrier, 1)
-	__flg_field_def(17, GENLA_F_MANDATORY,	disk_flushes, 1)
-	__flg_field_def(18, GENLA_F_MANDATORY,	disk_drain, 1)
-	__flg_field_def(19, GENLA_F_MANDATORY,	md_flushes, 1)
+	__flg_field_def(16, GENLA_F_MANDATORY,	disk_barrier, DRBD_DISK_BARRIER_DEF)
+	__flg_field_def(17, GENLA_F_MANDATORY,	disk_flushes, DRBD_DISK_FLUSHES_DEF)
+	__flg_field_def(18, GENLA_F_MANDATORY,	disk_drain, DRBD_DISK_DRAIN_DEF)
+	__flg_field_def(19, GENLA_F_MANDATORY,	md_flushes, DRBD_MD_FLUSHES_DEF)
 )
 
 GENL_struct(DRBD_NLA_RESOURCE_OPTS, 4, res_opts,
@@ -162,12 +162,12 @@ GENL_struct(DRBD_NLA_NET_CONF, 5, net_conf,
 	__u32_field_def(23,	GENLA_F_MANDATORY,	on_congestion, DRBD_ON_CONGESTION_DEF)
 	__u32_field_def(24,	GENLA_F_MANDATORY,	cong_fill, DRBD_CONG_FILL_DEF)
 	__u32_field_def(25,	GENLA_F_MANDATORY,	cong_extents, DRBD_CONG_EXTENTS_DEF)
-	__flg_field_def(26, GENLA_F_MANDATORY,	two_primaries, 0)
+	__flg_field_def(26, GENLA_F_MANDATORY,	two_primaries, DRBD_ALLOW_TWO_PRIMARIES_DEF)
 	__flg_field(27, GENLA_F_MANDATORY | GENLA_F_INVARIANT,	want_lose)
-	__flg_field_def(28, GENLA_F_MANDATORY,	tcp_cork, 1)
-	__flg_field_def(29, GENLA_F_MANDATORY,	always_asbp, 0)
+	__flg_field_def(28, GENLA_F_MANDATORY,	tcp_cork, DRBD_TCP_CORK_DEF)
+	__flg_field_def(29, GENLA_F_MANDATORY,	always_asbp, DRBD_ALWAYS_ASBP_DEF)
 	__flg_field(30, GENLA_F_MANDATORY | GENLA_F_INVARIANT,	dry_run)
-	__flg_field_def(31,	GENLA_F_MANDATORY,	use_rle, 0)
+	__flg_field_def(31,	GENLA_F_MANDATORY,	use_rle, DRBD_USE_RLE_DEF)
 )
 
 GENL_struct(DRBD_NLA_SET_ROLE_PARMS, 6, set_role_parms,
diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
index 52530aa..f44a0b3 100644
--- a/include/linux/drbd_limits.h
+++ b/include/linux/drbd_limits.h
@@ -168,4 +168,14 @@
 
 #define DRBD_PROTOCOL_DEF DRBD_PROT_C
 
+#define DRBD_DISK_BARRIER_DEF	1
+#define DRBD_DISK_FLUSHES_DEF	1
+#define DRBD_DISK_DRAIN_DEF	1
+#define DRBD_MD_FLUSHES_DEF	1
+#define DRBD_TCP_CORK_DEF	1
+
+#define DRBD_ALLOW_TWO_PRIMARIES_DEF	0
+#define DRBD_ALWAYS_ASBP_DEF	0
+#define DRBD_USE_RLE_DEF	0
+
 #endif
-- 
1.7.4.1

[PATCH 06/12] drbd: Rename the want_lose field/flag to discard_my_data

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

This is what it is called in config files and on the command line as
well.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_int.h      |    2 +-
 drivers/block/drbd/drbd_main.c     |    6 +++---
 drivers/block/drbd/drbd_nl.c       |    4 ++--
 drivers/block/drbd/drbd_receiver.c |   14 +++++++-------
 include/linux/drbd_genl.h          |    2 +-
 5 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 56b190c..fa36757 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -413,7 +413,7 @@ struct p_rs_param_95 {
 } __packed;
 
 enum drbd_conn_flags {
-	CF_WANT_LOSE = 1,
+	CF_DISCARD_MY_DATA = 1,
 	CF_DRY_RUN = 2,
 };
 
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index dd5b56c..a3154be 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -943,8 +943,8 @@ int __drbd_send_protocol(struct drbd_tconn *tconn)
 	p->after_sb_2p   = cpu_to_be32(nc->after_sb_2p);
 	p->two_primaries = cpu_to_be32(nc->two_primaries);
 	cf = 0;
-	if (nc->want_lose)
-		cf |= CF_WANT_LOSE;
+	if (nc->discard_my_data)
+		cf |= CF_DISCARD_MY_DATA;
 	if (nc->dry_run)
 		cf |= CF_DRY_RUN;
 	p->conn_flags    = cpu_to_be32(cf);
@@ -988,7 +988,7 @@ int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
 	mdev->comm_bm_set = drbd_bm_total_weight(mdev);
 	p->uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
 	rcu_read_lock();
-	uuid_flags |= rcu_dereference(mdev->tconn->net_conf)->want_lose ? 1 : 0;
+	uuid_flags |= rcu_dereference(mdev->tconn->net_conf)->discard_my_data ? 1 : 0;
 	rcu_read_unlock();
 	uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
 	uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index caa8ba2..64de372 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -628,7 +628,7 @@ drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, int force)
 		mutex_lock(&mdev->tconn->conf_update);
 		nc = mdev->tconn->net_conf;
 		if (nc)
-			nc->want_lose = 0; /* without copy; single bit op is atomic */
+			nc->discard_my_data = 0; /* without copy; single bit op is atomic */
 		mutex_unlock(&mdev->tconn->conf_update);
 
 		set_disk_ro(mdev->vdisk, false);
@@ -1774,7 +1774,7 @@ _check_net_options(struct drbd_tconn *tconn, struct net_conf *old_conf, struct n
 			if (new_conf->wire_protocol == DRBD_PROT_A && fp == FP_STONITH)
 				return ERR_STONITH_AND_PROT_A;
 		}
-		if (mdev->state.role == R_PRIMARY && new_conf->want_lose)
+		if (mdev->state.role == R_PRIMARY && new_conf->discard_my_data)
 			return ERR_DISCARD;
 
 		if (!mdev->bitmap) {
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index aa42967..e4e8f8a 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -2908,9 +2908,9 @@ static enum drbd_conns drbd_sync_handshake(struct drbd_conf *mdev, enum drbd_rol
 	}
 
 	if (hg == -100) {
-		if (nc->want_lose && !(mdev->p_uuid[UI_FLAGS]&1))
+		if (nc->discard_my_data && !(mdev->p_uuid[UI_FLAGS]&1))
 			hg = -1;
-		if (!nc->want_lose && (mdev->p_uuid[UI_FLAGS]&1))
+		if (!nc->discard_my_data && (mdev->p_uuid[UI_FLAGS]&1))
 			hg = 1;
 
 		if (abs(hg) < 100)
@@ -3009,7 +3009,7 @@ static int receive_protocol(struct drbd_tconn *tconn, struct packet_info *pi)
 {
 	struct p_protocol *p = pi->data;
 	int p_proto, p_after_sb_0p, p_after_sb_1p, p_after_sb_2p;
-	int p_want_lose, p_two_primaries, cf;
+	int p_discard_my_data, p_two_primaries, cf;
 	struct net_conf *nc;
 
 	p_proto		= be32_to_cpu(p->protocol);
@@ -3018,7 +3018,7 @@ static int receive_protocol(struct drbd_tconn *tconn, struct packet_info *pi)
 	p_after_sb_2p	= be32_to_cpu(p->after_sb_2p);
 	p_two_primaries = be32_to_cpu(p->two_primaries);
 	cf		= be32_to_cpu(p->conn_flags);
-	p_want_lose = cf & CF_WANT_LOSE;
+	p_discard_my_data = cf & CF_DISCARD_MY_DATA;
 
 	if (tconn->agreed_pro_version >= 87) {
 		char integrity_alg[SHARED_SECRET_MAX];
@@ -3075,8 +3075,8 @@ static int receive_protocol(struct drbd_tconn *tconn, struct packet_info *pi)
 		goto disconnect_rcu_unlock;
 	}
 
-	if (p_want_lose && nc->want_lose) {
-		conn_err(tconn, "both sides have the 'want_lose' flag set\n");
+	if (p_discard_my_data && nc->discard_my_data) {
+		conn_err(tconn, "both sides have the 'discard_my_data' flag set\n");
 		goto disconnect_rcu_unlock;
 	}
 
@@ -3806,7 +3806,7 @@ static int receive_state(struct drbd_tconn *tconn, struct packet_info *pi)
 	}
 
 	mutex_lock(&mdev->tconn->conf_update);
-	mdev->tconn->net_conf->want_lose = 0; /* without copy; single bit op is atomic */
+	mdev->tconn->net_conf->discard_my_data = 0; /* without copy; single bit op is atomic */
 	mutex_unlock(&mdev->tconn->conf_update);
 
 	drbd_md_sync(mdev); /* update connected indicator, la_size, ... */
diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index eba635a..1d707f9 100644
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -163,7 +163,7 @@ GENL_struct(DRBD_NLA_NET_CONF, 5, net_conf,
 	__u32_field_def(24,	GENLA_F_MANDATORY,	cong_fill, DRBD_CONG_FILL_DEF)
 	__u32_field_def(25,	GENLA_F_MANDATORY,	cong_extents, DRBD_CONG_EXTENTS_DEF)
 	__flg_field_def(26, GENLA_F_MANDATORY,	two_primaries, DRBD_ALLOW_TWO_PRIMARIES_DEF)
-	__flg_field(27, GENLA_F_MANDATORY | GENLA_F_INVARIANT,	want_lose)
+	__flg_field(27, GENLA_F_MANDATORY | GENLA_F_INVARIANT,	discard_my_data)
 	__flg_field_def(28, GENLA_F_MANDATORY,	tcp_cork, DRBD_TCP_CORK_DEF)
 	__flg_field_def(29, GENLA_F_MANDATORY,	always_asbp, DRBD_ALWAYS_ASBP_DEF)
 	__flg_field(30, GENLA_F_MANDATORY | GENLA_F_INVARIANT,	dry_run)
-- 
1.7.4.1

[PATCH 07/12] drbd: skip spurious wait_event in drbd_al_begin_io

[Philipp Reisner]

From: Lars Ellenberg <lars.ellenberg@linbit.com>

Activity log transaction writes are serialized on a bit lock.
If several CPUs race to write an AL transaction,
those that did not get the lock the first time
may continue as soon as there are no more pending transactions.

The do not need to all grab the lock in turn,
just to realize that the AL is clean already,
and they have nothing to do.

This also closes a potential deadlock with drbd_adm_disk_opts.
Once it got the AL bit lock, it knows there are no pending transactions,
the AL is clean, and it should be safe to wait for all element references
to drop to zero.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_actlog.c |   18 ++++++++++--------
 1 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c
index 933404e..aeb483d 100644
--- a/drivers/block/drbd/drbd_actlog.c
+++ b/drivers/block/drbd/drbd_actlog.c
@@ -212,13 +212,22 @@ void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i)
 	unsigned first = i->sector >> (AL_EXTENT_SHIFT-9);
 	unsigned last = (i->sector + (i->size >> 9) - 1) >> (AL_EXTENT_SHIFT-9);
 	unsigned enr;
+	bool locked = false;
+
 
 	D_ASSERT(atomic_read(&mdev->local_cnt) > 0);
 
 	for (enr = first; enr <= last; enr++)
 		wait_event(mdev->al_wait, _al_get(mdev, enr) != NULL);
 
-	if (mdev->act_log->pending_changes) {
+	/* Serialize multiple transactions.
+	 * This uses test_and_set_bit, memory barrier is implicit.
+	 */
+	wait_event(mdev->al_wait,
+			mdev->act_log->pending_changes == 0 ||
+			(locked = lc_try_lock_for_transaction(mdev->act_log)));
+
+	if (locked) {
 		/* drbd_al_write_transaction(mdev,al_ext,enr);
 		 * recurses into generic_make_request(), which
 		 * disallows recursion, bios being serialized on the
@@ -226,13 +235,6 @@ void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i)
 		 * we have to delegate updates to the activity log
 		 * to the worker thread. */
 
-		/* Serialize multiple transactions.
-		 * This uses test_and_set_bit, memory barrier is implicit.
-		 * Optimization potential:
-		 * first check for transaction number > old transaction number,
-		 * so not all waiters have to lock/unlock.  */
-		wait_event(mdev->al_wait, lc_try_lock_for_transaction(mdev->act_log));
-
 		/* Double check: it may have been committed by someone else,
 		 * while we have been waiting for the lock. */
 		if (mdev->act_log->pending_changes) {
-- 
1.7.4.1

[PATCH 08/12] drbd: Refer to resync-rate consistently throughout the code

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_int.h      |    6 +++---
 drivers/block/drbd/drbd_main.c     |    4 ++--
 drivers/block/drbd/drbd_receiver.c |    2 +-
 include/linux/drbd_genl.h          |    2 +-
 include/linux/drbd_limits.h        |    7 ++++---
 5 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index fa36757..8026ada 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -389,21 +389,21 @@ struct p_barrier_ack {
 } __packed;
 
 struct p_rs_param {
-	u32 rate;
+	u32 resync_rate;
 
 	      /* Since protocol version 88 and higher. */
 	char verify_alg[0];
 } __packed;
 
 struct p_rs_param_89 {
-	u32 rate;
+	u32 resync_rate;
         /* protocol version 89: */
 	char verify_alg[SHARED_SECRET_MAX];
 	char csums_alg[SHARED_SECRET_MAX];
 } __packed;
 
 struct p_rs_param_95 {
-	u32 rate;
+	u32 resync_rate;
 	char verify_alg[SHARED_SECRET_MAX];
 	char csums_alg[SHARED_SECRET_MAX];
 	u32 c_plan_ahead;
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index a3154be..939d31b 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -888,14 +888,14 @@ int drbd_send_sync_param(struct drbd_conf *mdev)
 
 	if (get_ldev(mdev)) {
 		dc = rcu_dereference(mdev->ldev->disk_conf);
-		p->rate = cpu_to_be32(dc->resync_rate);
+		p->resync_rate = cpu_to_be32(dc->resync_rate);
 		p->c_plan_ahead = cpu_to_be32(dc->c_plan_ahead);
 		p->c_delay_target = cpu_to_be32(dc->c_delay_target);
 		p->c_fill_target = cpu_to_be32(dc->c_fill_target);
 		p->c_max_rate = cpu_to_be32(dc->c_max_rate);
 		put_ldev(mdev);
 	} else {
-		p->rate = cpu_to_be32(DRBD_RATE_DEF);
+		p->resync_rate = cpu_to_be32(DRBD_RESYNC_RATE_DEF);
 		p->c_plan_ahead = cpu_to_be32(DRBD_C_PLAN_AHEAD_DEF);
 		p->c_delay_target = cpu_to_be32(DRBD_C_DELAY_TARGET_DEF);
 		p->c_fill_target = cpu_to_be32(DRBD_C_FILL_TARGET_DEF);
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index e4e8f8a..684f795 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -3221,7 +3221,7 @@ static int receive_SyncParam(struct drbd_tconn *tconn, struct packet_info *pi)
 		old_disk_conf = mdev->ldev->disk_conf;
 		*new_disk_conf = *old_disk_conf;
 
-		new_disk_conf->resync_rate = be32_to_cpu(p->rate);
+		new_disk_conf->resync_rate = be32_to_cpu(p->resync_rate);
 	}
 
 	if (apv >= 88) {
diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index 1d707f9..4d76d0a 100644
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -115,7 +115,7 @@ GENL_struct(DRBD_NLA_DISK_CONF, 3, disk_conf,
 	__u32_field_def(6, GENLA_F_MANDATORY,	on_io_error, DRBD_ON_IO_ERROR_DEF)
 	__u32_field_def(7, GENLA_F_MANDATORY,	fencing, DRBD_FENCING_DEF)
 
-	__u32_field_def(8,	GENLA_F_MANDATORY,	resync_rate, DRBD_RATE_DEF)
+	__u32_field_def(8,	GENLA_F_MANDATORY,	resync_rate, DRBD_RESYNC_RATE_DEF)
 	__u32_field_def(9,	GENLA_F_MANDATORY,	resync_after, DRBD_AFTER_DEF)
 	__u32_field_def(10,	GENLA_F_MANDATORY,	al_extents, DRBD_AL_EXTENTS_DEF)
 	__u32_field_def(11,	GENLA_F_MANDATORY,	c_plan_ahead, DRBD_C_PLAN_AHEAD_DEF)
diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
index f44a0b3..27f5a13 100644
--- a/include/linux/drbd_limits.h
+++ b/include/linux/drbd_limits.h
@@ -96,10 +96,11 @@
 
 /* syncer { */
   /* FIXME allow rate to be zero? */
-#define DRBD_RATE_MIN 1
+#define DRBD_RESYNC_RATE_MIN 1
 /* channel bonding 10 GbE, or other hardware */
-#define DRBD_RATE_MAX (4 << 20)
-#define DRBD_RATE_DEF 250  /* kb/second */
+#define DRBD_RESYNC_RATE_MAX (4 << 20)
+#define DRBD_RESYNC_RATE_DEF 250
+#define DRBD_RESYNC_RATE_SCALE 'k'  /* kilobytes */
 
   /* less than 7 would hit performance unnecessarily.
    * 919 slots context information per transaction,
-- 
1.7.4.1

[PATCH 09/12] drbd: Refer to connect-int consistently throughout the code

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_receiver.c |   12 ++++++------
 include/linux/drbd_genl.h          |    2 +-
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 684f795..7deade1 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -617,7 +617,7 @@ static struct socket *drbd_try_connect(struct drbd_tconn *tconn)
 	struct sockaddr_in6 peer_in6;
 	struct net_conf *nc;
 	int err, peer_addr_len, my_addr_len;
-	int sndbuf_size, rcvbuf_size, try_connect_int;
+	int sndbuf_size, rcvbuf_size, connect_int;
 	int disconnect_on_error = 1;
 
 	rcu_read_lock();
@@ -629,7 +629,7 @@ static struct socket *drbd_try_connect(struct drbd_tconn *tconn)
 
 	sndbuf_size = nc->sndbuf_size;
 	rcvbuf_size = nc->rcvbuf_size;
-	try_connect_int = nc->try_connect_int;
+	connect_int = nc->connect_int;
 
 	my_addr_len = min_t(int, nc->my_addr_len, sizeof(src_in6));
 	memcpy(&src_in6, nc->my_addr, my_addr_len);
@@ -653,7 +653,7 @@ static struct socket *drbd_try_connect(struct drbd_tconn *tconn)
 	}
 
 	sock->sk->sk_rcvtimeo =
-	sock->sk->sk_sndtimeo = try_connect_int * HZ;
+	sock->sk->sk_sndtimeo = connect_int * HZ;
 	drbd_setbufsize(sock, sndbuf_size, rcvbuf_size);
 
        /* explicitly bind to the configured IP as source IP
@@ -702,7 +702,7 @@ out:
 static struct socket *drbd_wait_for_connect(struct drbd_tconn *tconn)
 {
 	int timeo, err, my_addr_len;
-	int sndbuf_size, rcvbuf_size, try_connect_int;
+	int sndbuf_size, rcvbuf_size, connect_int;
 	struct socket *s_estab = NULL, *s_listen;
 	struct sockaddr_in6 my_addr;
 	struct net_conf *nc;
@@ -717,7 +717,7 @@ static struct socket *drbd_wait_for_connect(struct drbd_tconn *tconn)
 
 	sndbuf_size = nc->sndbuf_size;
 	rcvbuf_size = nc->rcvbuf_size;
-	try_connect_int = nc->try_connect_int;
+	connect_int = nc->connect_int;
 
 	my_addr_len = min_t(int, nc->my_addr_len, sizeof(struct sockaddr_in6));
 	memcpy(&my_addr, nc->my_addr, my_addr_len);
@@ -731,7 +731,7 @@ static struct socket *drbd_wait_for_connect(struct drbd_tconn *tconn)
 		goto out;
 	}
 
-	timeo = try_connect_int * HZ;
+	timeo = connect_int * HZ;
 	timeo += (random32() & 1) ? timeo / 7 : -timeo / 7; /* 28.5% random jitter */
 
 	s_listen->sk->sk_reuse    = 1; /* SO_REUSEADDR */
diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index 4d76d0a..07b4f4a 100644
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -145,7 +145,7 @@ GENL_struct(DRBD_NLA_NET_CONF, 5, net_conf,
 	__str_field_def(6,	GENLA_F_MANDATORY,	verify_alg,     SHARED_SECRET_MAX)
 	__str_field_def(7,	GENLA_F_MANDATORY,	csums_alg,	SHARED_SECRET_MAX)
 	__u32_field_def(8,	GENLA_F_MANDATORY,	wire_protocol, DRBD_PROTOCOL_DEF)
-	__u32_field_def(9,	GENLA_F_MANDATORY,	try_connect_int, DRBD_CONNECT_INT_DEF)
+	__u32_field_def(9,	GENLA_F_MANDATORY,	connect_int, DRBD_CONNECT_INT_DEF)
 	__u32_field_def(10,	GENLA_F_MANDATORY,	timeout, DRBD_TIMEOUT_DEF)
 	__u32_field_def(11,	GENLA_F_MANDATORY,	ping_int, DRBD_PING_INT_DEF)
 	__u32_field_def(12,	GENLA_F_MANDATORY,	ping_timeo, DRBD_PING_TIMEO_DEF)
-- 
1.7.4.1

[PATCH 10/12] drbd: Fix the upper limit of resync-after

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

The 32-bit resync_after netlink field takes a device minor number as
parameter, which is no longer limited to 255.  We cannot statically
verify which device numbers are valid, so set the ummer limit to the
highest possible signed 32-bit integer.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_int.h    |    4 ++--
 drivers/block/drbd/drbd_nl.c     |    4 ++--
 drivers/block/drbd/drbd_worker.c |   26 +++++++++++++-------------
 include/linux/drbd.h             |    4 ++--
 include/linux/drbd_genl.h        |    2 +-
 include/linux/drbd_limits.h      |    7 ++++---
 6 files changed, 24 insertions(+), 23 deletions(-)

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 8026ada..e167228 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -1408,8 +1408,8 @@ extern int drbd_khelper(struct drbd_conf *mdev, char *cmd);
 
 /* drbd_worker.c */
 extern int drbd_worker(struct drbd_thread *thi);
-enum drbd_ret_code drbd_sync_after_valid(struct drbd_conf *mdev, int o_minor);
-void drbd_sync_after_changed(struct drbd_conf *mdev);
+enum drbd_ret_code drbd_resync_after_valid(struct drbd_conf *mdev, int o_minor);
+void drbd_resync_after_changed(struct drbd_conf *mdev);
 extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side);
 extern void resume_next_sg(struct drbd_conf *mdev);
 extern void suspend_other_sg(struct drbd_conf *mdev);
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 64de372..e67ce20 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1219,10 +1219,10 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	write_lock_irq(&global_state_lock);
-	retcode = drbd_sync_after_valid(mdev, new_disk_conf->resync_after);
+	retcode = drbd_resync_after_valid(mdev, new_disk_conf->resync_after);
 	if (retcode == NO_ERROR) {
 		rcu_assign_pointer(mdev->ldev->disk_conf, new_disk_conf);
-		drbd_sync_after_changed(mdev);
+		drbd_resync_after_changed(mdev);
 	}
 	write_unlock_irq(&global_state_lock);
 
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 46b5f7f..85bcab9 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -57,7 +57,7 @@ static int w_make_ov_request(struct drbd_work *w, int cancel);
 
 /* About the global_state_lock
    Each state transition on an device holds a read lock. In case we have
-   to evaluate the sync after dependencies, we grab a write lock, because
+   to evaluate the resync after dependencies, we grab a write lock, because
    we need stable states on all devices for that.  */
 rwlock_t global_state_lock;
 
@@ -1340,17 +1340,17 @@ int w_restart_disk_io(struct drbd_work *w, int cancel)
 static int _drbd_may_sync_now(struct drbd_conf *mdev)
 {
 	struct drbd_conf *odev = mdev;
-	int ra;
+	int resync_after;
 
 	while (1) {
 		if (!odev->ldev)
 			return 1;
 		rcu_read_lock();
-		ra = rcu_dereference(odev->ldev->disk_conf)->resync_after;
+		resync_after = rcu_dereference(odev->ldev->disk_conf)->resync_after;
 		rcu_read_unlock();
-		if (ra == -1)
+		if (resync_after == -1)
 			return 1;
-		odev = minor_to_mdev(ra);
+		odev = minor_to_mdev(resync_after);
 		if (!expect(odev))
 			return 1;
 		if ((odev->state.conn >= C_SYNC_SOURCE &&
@@ -1426,36 +1426,36 @@ void suspend_other_sg(struct drbd_conf *mdev)
 }
 
 /* caller must hold global_state_lock */
-enum drbd_ret_code drbd_sync_after_valid(struct drbd_conf *mdev, int o_minor)
+enum drbd_ret_code drbd_resync_after_valid(struct drbd_conf *mdev, int o_minor)
 {
 	struct drbd_conf *odev;
-	int ra;
+	int resync_after;
 
 	if (o_minor == -1)
 		return NO_ERROR;
 	if (o_minor < -1 || minor_to_mdev(o_minor) == NULL)
-		return ERR_SYNC_AFTER;
+		return ERR_RESYNC_AFTER;
 
 	/* check for loops */
 	odev = minor_to_mdev(o_minor);
 	while (1) {
 		if (odev == mdev)
-			return ERR_SYNC_AFTER_CYCLE;
+			return ERR_RESYNC_AFTER_CYCLE;
 
 		rcu_read_lock();
-		ra = rcu_dereference(odev->ldev->disk_conf)->resync_after;
+		resync_after = rcu_dereference(odev->ldev->disk_conf)->resync_after;
 		rcu_read_unlock();
 		/* dependency chain ends here, no cycles. */
-		if (ra == -1)
+		if (resync_after == -1)
 			return NO_ERROR;
 
 		/* follow the dependency chain */
-		odev = minor_to_mdev(ra);
+		odev = minor_to_mdev(resync_after);
 	}
 }
 
 /* caller must hold global_state_lock */
-void drbd_sync_after_changed(struct drbd_conf *mdev)
+void drbd_resync_after_changed(struct drbd_conf *mdev)
 {
 	int changes;
 
diff --git a/include/linux/drbd.h b/include/linux/drbd.h
index 6c7c85d..05063e6 100644
--- a/include/linux/drbd.h
+++ b/include/linux/drbd.h
@@ -130,8 +130,8 @@ enum drbd_ret_code {
 	ERR_INTR		= 129, /* EINTR */
 	ERR_RESIZE_RESYNC	= 130,
 	ERR_NO_PRIMARY		= 131,
-	ERR_SYNC_AFTER		= 132,
-	ERR_SYNC_AFTER_CYCLE	= 133,
+	ERR_RESYNC_AFTER	= 132,
+	ERR_RESYNC_AFTER_CYCLE	= 133,
 	ERR_PAUSE_IS_SET	= 134,
 	ERR_PAUSE_IS_CLEAR	= 135,
 	ERR_PACKET_NR		= 137,
diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index 07b4f4a..40606ad 100644
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -116,7 +116,7 @@ GENL_struct(DRBD_NLA_DISK_CONF, 3, disk_conf,
 	__u32_field_def(7, GENLA_F_MANDATORY,	fencing, DRBD_FENCING_DEF)
 
 	__u32_field_def(8,	GENLA_F_MANDATORY,	resync_rate, DRBD_RESYNC_RATE_DEF)
-	__u32_field_def(9,	GENLA_F_MANDATORY,	resync_after, DRBD_AFTER_DEF)
+	__u32_field_def(9,	GENLA_F_MANDATORY,	resync_after, DRBD_RESYNC_AFTER_DEF)
 	__u32_field_def(10,	GENLA_F_MANDATORY,	al_extents, DRBD_AL_EXTENTS_DEF)
 	__u32_field_def(11,	GENLA_F_MANDATORY,	c_plan_ahead, DRBD_C_PLAN_AHEAD_DEF)
 	__u32_field_def(12,	GENLA_F_MANDATORY,	c_delay_target, DRBD_C_DELAY_TARGET_DEF)
diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
index 27f5a13..62e93b2 100644
--- a/include/linux/drbd_limits.h
+++ b/include/linux/drbd_limits.h
@@ -111,9 +111,10 @@
 #define DRBD_AL_EXTENTS_MAX  6433
 #define DRBD_AL_EXTENTS_DEF  127
 
-#define DRBD_AFTER_MIN  -1
-#define DRBD_AFTER_MAX  255
-#define DRBD_AFTER_DEF  -1
+#define DRBD_RESYNC_AFTER_MIN  -1
+#define DRBD_RESYNC_AFTER_MAX  (1<<30)
+#define DRBD_RESYNC_AFTER_DEF  -1
+#define DRBD_RESYNC_AFTER_SCALE '1'
 
 /* } */
 
-- 
1.7.4.1

[PATCH 11/12] drbd: Convert resync-after into a signed netlink field

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 include/linux/drbd_genl.h         |    2 +-
 include/linux/genl_magic_func.h   |    3 +++
 include/linux/genl_magic_struct.h |    2 ++
 3 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index 40606ad..4b446af 100644
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -116,7 +116,7 @@ GENL_struct(DRBD_NLA_DISK_CONF, 3, disk_conf,
 	__u32_field_def(7, GENLA_F_MANDATORY,	fencing, DRBD_FENCING_DEF)
 
 	__u32_field_def(8,	GENLA_F_MANDATORY,	resync_rate, DRBD_RESYNC_RATE_DEF)
-	__u32_field_def(9,	GENLA_F_MANDATORY,	resync_after, DRBD_RESYNC_AFTER_DEF)
+	__s32_field_def(9,	GENLA_F_MANDATORY,	resync_after, DRBD_RESYNC_AFTER_DEF)
 	__u32_field_def(10,	GENLA_F_MANDATORY,	al_extents, DRBD_AL_EXTENTS_DEF)
 	__u32_field_def(11,	GENLA_F_MANDATORY,	c_plan_ahead, DRBD_C_PLAN_AHEAD_DEF)
 	__u32_field_def(12,	GENLA_F_MANDATORY,	c_delay_target, DRBD_C_DELAY_TARGET_DEF)
diff --git a/include/linux/genl_magic_func.h b/include/linux/genl_magic_func.h
index ce02500..e8e1220 100644
--- a/include/linux/genl_magic_func.h
+++ b/include/linux/genl_magic_func.h
@@ -431,6 +431,9 @@ static inline int s_name ## _to_unpriv_skb(struct sk_buff *skb,		\
 #undef __u32_field_def
 #define __u32_field_def(attr_nr, attr_flag, name, default)		\
 	x->name = default;
+#undef __s32_field_def
+#define __s32_field_def(attr_nr, attr_flag, name, default)		\
+	x->name = default;
 #undef __flg_field_def
 #define __flg_field_def(attr_nr, attr_flag, name, default)		\
 	x->name = default;
diff --git a/include/linux/genl_magic_struct.h b/include/linux/genl_magic_struct.h
index b1ddbb5..0fca21f 100644
--- a/include/linux/genl_magic_struct.h
+++ b/include/linux/genl_magic_struct.h
@@ -115,6 +115,8 @@ enum {
 	__flg_field(attr_nr, attr_flag, name)
 #define __u32_field_def(attr_nr, attr_flag, name, default) \
 	__u32_field(attr_nr, attr_flag, name)
+#define __s32_field_def(attr_nr, attr_flag, name, default) \
+	__s32_field(attr_nr, attr_flag, name)
 #define __str_field_def(attr_nr, attr_flag, name, maxlen) \
 	__str_field(attr_nr, attr_flag, name, maxlen)
 
-- 
1.7.4.1

[PATCH 12/12] drbd: Rename DISK_SIZE_SECT -> DISK_SIZE

[Philipp Reisner]

From: Andreas Gruenbacher <agruen@linbit.com>

We don't have the units in constant names in other places, either.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 include/linux/drbd_limits.h |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
index 62e93b2..07d5df9 100644
--- a/include/linux/drbd_limits.h
+++ b/include/linux/drbd_limits.h
@@ -123,9 +123,10 @@
  * the upper limit with 64bit kernel, enough ram and flexible meta data
  * is 1 PiB, currently. */
 /* DRBD_MAX_SECTORS */
-#define DRBD_DISK_SIZE_SECT_MIN  0
-#define DRBD_DISK_SIZE_SECT_MAX  (1 * (2LLU << 40))
-#define DRBD_DISK_SIZE_SECT_DEF  0 /* = disabled = no user size... */
+#define DRBD_DISK_SIZE_MIN  0
+#define DRBD_DISK_SIZE_MAX  (16 * (2LLU << 30))
+#define DRBD_DISK_SIZE_DEF  0 /* = disabled = no user size... */
+#define DRBD_DISK_SIZE_SCALE 's'  /* sectors */
 
 #define DRBD_ON_IO_ERROR_DEF EP_DETACH
 #define DRBD_FENCING_DEF FP_DONT_CARE
-- 
1.7.4.1