Merge branch 'for-3.17/drivers' of git://git.kernel.dk/linux-block

Pull block driver changes from Jens Axboe:
 "Nothing out of the ordinary here, this pull request contains:

   - A big round of fixes for bcache from Kent Overstreet, Slava Pestov,
     and Surbhi Palande.  No new features, just a lot of fixes.

   - The usual round of drbd updates from Andreas Gruenbacher, Lars
     Ellenberg, and Philipp Reisner.

   - virtio_blk was converted to blk-mq back in 3.13, but now Ming Lei
     has taken it one step further and added support for actually using
     more than one queue.

   - Addition of an explicit SG_FLAG_Q_AT_HEAD for block/bsg, to
     compliment the the default behavior of adding to the tail of the
     queue.  From Douglas Gilbert"

* 'for-3.17/drivers' of git://git.kernel.dk/linux-block: (86 commits)
  bcache: Drop unneeded blk_sync_queue() calls
  bcache: add mutex lock for bch_is_open
  bcache: Correct printing of btree_gc_max_duration_ms
  bcache: try to set b->parent properly
  bcache: fix memory corruption in init error path
  bcache: fix crash with incomplete cache set
  bcache: Fix more early shutdown bugs
  bcache: fix use-after-free in btree_gc_coalesce()
  bcache: Fix an infinite loop in journal replay
  bcache: fix crash in bcache_btree_node_alloc_fail tracepoint
  bcache: bcache_write tracepoint was crashing
  bcache: fix typo in bch_bkey_equal_header
  bcache: Allocate bounce buffers with GFP_NOWAIT
  bcache: Make sure to pass GFP_WAIT to mempool_alloc()
  bcache: fix uninterruptible sleep in writeback thread
  bcache: wait for buckets when allocating new btree root
  bcache: fix crash on shutdown in passthrough mode
  bcache: fix lockdep warnings on shutdown
  bcache allocator: send discards with correct size
  bcache: Fix to remove the rcu_sched stalls.
  ...

1 files changed, 49 insertions, 41 deletions

diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c
index a5d8aae00e04..c35c0f001bb7 100644
--- a/drivers/block/drbd/drbd_state.c
+++ b/drivers/block/drbd/drbd_state.c
@@ -410,7 +410,7 @@ _drbd_request_state(struct drbd_device *device, union drbd_state mask,
 	return rv;
 }
 
-static void print_st(struct drbd_device *device, char *name, union drbd_state ns)
+static void print_st(struct drbd_device *device, const char *name, union drbd_state ns)
 {
 	drbd_err(device, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c%c%c }\n",
 	    name,
@@ -952,11 +952,12 @@ enum drbd_state_rv
 __drbd_set_state(struct drbd_device *device, union drbd_state ns,
 	         enum chg_state_flags flags, struct completion *done)
 {
+	struct drbd_peer_device *peer_device = first_peer_device(device);
+	struct drbd_connection *connection = peer_device ? peer_device->connection : NULL;
 	union drbd_state os;
 	enum drbd_state_rv rv = SS_SUCCESS;
 	enum sanitize_state_warnings ssw;
 	struct after_state_chg_work *ascw;
-	bool did_remote, should_do_remote;
 
 	os = drbd_read_state(device);
 
@@ -978,9 +979,9 @@ __drbd_set_state(struct drbd_device *device, union drbd_state ns,
 			   this happen...*/
 
 			if (is_valid_state(device, os) == rv)
-				rv = is_valid_soft_transition(os, ns, first_peer_device(device)->connection);
+				rv = is_valid_soft_transition(os, ns, connection);
 		} else
-			rv = is_valid_soft_transition(os, ns, first_peer_device(device)->connection);
+			rv = is_valid_soft_transition(os, ns, connection);
 	}
 
 	if (rv < SS_SUCCESS) {
@@ -997,7 +998,7 @@ __drbd_set_state(struct drbd_device *device, union drbd_state ns,
 	   sanitize_state(). Only display it here if we where not called from
 	   _conn_request_state() */
 	if (!(flags & CS_DC_SUSP))
-		conn_pr_state_change(first_peer_device(device)->connection, os, ns,
+		conn_pr_state_change(connection, os, ns,
 				     (flags & ~CS_DC_MASK) | CS_DC_SUSP);
 
 	/* if we are going -> D_FAILED or D_DISKLESS, grab one extra reference
@@ -1008,28 +1009,35 @@ __drbd_set_state(struct drbd_device *device, union drbd_state ns,
 	    (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))
 		atomic_inc(&device->local_cnt);
 
-	did_remote = drbd_should_do_remote(device->state);
+	if (!is_sync_state(os.conn) && is_sync_state(ns.conn))
+		clear_bit(RS_DONE, &device->flags);
+
+	/* changes to local_cnt and device flags should be visible before
+	 * changes to state, which again should be visible before anything else
+	 * depending on that change happens. */
+	smp_wmb();
 	device->state.i = ns.i;
-	should_do_remote = drbd_should_do_remote(device->state);
 	device->resource->susp = ns.susp;
 	device->resource->susp_nod = ns.susp_nod;
 	device->resource->susp_fen = ns.susp_fen;
+	smp_wmb();
 
 	/* put replicated vs not-replicated requests in seperate epochs */
-	if (did_remote != should_do_remote)
-		start_new_tl_epoch(first_peer_device(device)->connection);
+	if (drbd_should_do_remote((union drbd_dev_state)os.i) !=
+	    drbd_should_do_remote((union drbd_dev_state)ns.i))
+		start_new_tl_epoch(connection);
 
 	if (os.disk == D_ATTACHING && ns.disk >= D_NEGOTIATING)
 		drbd_print_uuids(device, "attached to UUIDs");
 
 	/* Wake up role changes, that were delayed because of connection establishing */
 	if (os.conn == C_WF_REPORT_PARAMS && ns.conn != C_WF_REPORT_PARAMS &&
-	    no_peer_wf_report_params(first_peer_device(device)->connection))
-		clear_bit(STATE_SENT, &first_peer_device(device)->connection->flags);
+	    no_peer_wf_report_params(connection))
+		clear_bit(STATE_SENT, &connection->flags);
 
 	wake_up(&device->misc_wait);
 	wake_up(&device->state_wait);
-	wake_up(&first_peer_device(device)->connection->ping_wait);
+	wake_up(&connection->ping_wait);
 
 	/* Aborted verify run, or we reached the stop sector.
 	 * Log the last position, unless end-of-device. */
@@ -1118,21 +1126,21 @@ __drbd_set_state(struct drbd_device *device, union drbd_state ns,
 
 	/* Receiver should clean up itself */
 	if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
-		drbd_thread_stop_nowait(&first_peer_device(device)->connection->receiver);
+		drbd_thread_stop_nowait(&connection->receiver);
 
 	/* Now the receiver finished cleaning up itself, it should die */
 	if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
-		drbd_thread_stop_nowait(&first_peer_device(device)->connection->receiver);
+		drbd_thread_stop_nowait(&connection->receiver);
 
 	/* Upon network failure, we need to restart the receiver. */
 	if (os.conn > C_WF_CONNECTION &&
 	    ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
-		drbd_thread_restart_nowait(&first_peer_device(device)->connection->receiver);
+		drbd_thread_restart_nowait(&connection->receiver);
 
 	/* Resume AL writing if we get a connection */
 	if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) {
 		drbd_resume_al(device);
-		first_peer_device(device)->connection->connect_cnt++;
+		connection->connect_cnt++;
 	}
 
 	/* remember last attach time so request_timer_fn() won't
@@ -1150,7 +1158,7 @@ __drbd_set_state(struct drbd_device *device, union drbd_state ns,
 		ascw->w.cb = w_after_state_ch;
 		ascw->device = device;
 		ascw->done = done;
-		drbd_queue_work(&first_peer_device(device)->connection->sender_work,
+		drbd_queue_work(&connection->sender_work,
 				&ascw->w);
 	} else {
 		drbd_err(device, "Could not kmalloc an ascw\n");
@@ -1222,13 +1230,16 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 			   union drbd_state ns, enum chg_state_flags flags)
 {
 	struct drbd_resource *resource = device->resource;
+	struct drbd_peer_device *peer_device = first_peer_device(device);
+	struct drbd_connection *connection = peer_device ? peer_device->connection : NULL;
 	struct sib_info sib;
 
 	sib.sib_reason = SIB_STATE_CHANGE;
 	sib.os = os;
 	sib.ns = ns;
 
-	if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
+	if ((os.disk != D_UP_TO_DATE || os.pdsk != D_UP_TO_DATE)
+	&&  (ns.disk == D_UP_TO_DATE && ns.pdsk == D_UP_TO_DATE)) {
 		clear_bit(CRASHED_PRIMARY, &device->flags);
 		if (device->p_uuid)
 			device->p_uuid[UI_FLAGS] &= ~((u64)2);
@@ -1245,7 +1256,6 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 	   state change. This function might sleep */
 
 	if (ns.susp_nod) {
-		struct drbd_connection *connection = first_peer_device(device)->connection;
 		enum drbd_req_event what = NOTHING;
 
 		spin_lock_irq(&device->resource->req_lock);
@@ -1267,8 +1277,6 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 	}
 
 	if (ns.susp_fen) {
-		struct drbd_connection *connection = first_peer_device(device)->connection;
-
 		spin_lock_irq(&device->resource->req_lock);
 		if (resource->susp_fen && conn_lowest_conn(connection) >= C_CONNECTED) {
 			/* case2: The connection was established again: */
@@ -1294,8 +1302,8 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 	 * which is unexpected. */
 	if ((os.conn != C_SYNC_SOURCE && os.conn != C_PAUSED_SYNC_S) &&
 	    (ns.conn == C_SYNC_SOURCE || ns.conn == C_PAUSED_SYNC_S) &&
-	    first_peer_device(device)->connection->agreed_pro_version >= 96 && get_ldev(device)) {
-		drbd_gen_and_send_sync_uuid(first_peer_device(device));
+	    connection->agreed_pro_version >= 96 && get_ldev(device)) {
+		drbd_gen_and_send_sync_uuid(peer_device);
 		put_ldev(device);
 	}
 
@@ -1309,8 +1317,8 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 		atomic_set(&device->rs_pending_cnt, 0);
 		drbd_rs_cancel_all(device);
 
-		drbd_send_uuids(first_peer_device(device));
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_uuids(peer_device);
+		drbd_send_state(peer_device, ns);
 	}
 	/* No point in queuing send_bitmap if we don't have a connection
 	 * anymore, so check also the _current_ state, not only the new state
@@ -1335,7 +1343,7 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 					set_bit(NEW_CUR_UUID, &device->flags);
 				} else {
 					drbd_uuid_new_current(device);
-					drbd_send_uuids(first_peer_device(device));
+					drbd_send_uuids(peer_device);
 				}
 			}
 			put_ldev(device);
@@ -1346,7 +1354,7 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 		if (os.peer == R_SECONDARY && ns.peer == R_PRIMARY &&
 		    device->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
 			drbd_uuid_new_current(device);
-			drbd_send_uuids(first_peer_device(device));
+			drbd_send_uuids(peer_device);
 		}
 		/* D_DISKLESS Peer becomes secondary */
 		if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
@@ -1373,16 +1381,16 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 	/* Last part of the attaching process ... */
 	if (ns.conn >= C_CONNECTED &&
 	    os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
-		drbd_send_sizes(first_peer_device(device), 0, 0);  /* to start sync... */
-		drbd_send_uuids(first_peer_device(device));
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_sizes(peer_device, 0, 0);  /* to start sync... */
+		drbd_send_uuids(peer_device);
+		drbd_send_state(peer_device, ns);
 	}
 
 	/* We want to pause/continue resync, tell peer. */
 	if (ns.conn >= C_CONNECTED &&
 	     ((os.aftr_isp != ns.aftr_isp) ||
 	      (os.user_isp != ns.user_isp)))
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_state(peer_device, ns);
 
 	/* In case one of the isp bits got set, suspend other devices. */
 	if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
@@ -1392,10 +1400,10 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 	/* Make sure the peer gets informed about eventual state
 	   changes (ISP bits) while we were in WFReportParams. */
 	if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_state(peer_device, ns);
 
 	if (os.conn != C_AHEAD && ns.conn == C_AHEAD)
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_state(peer_device, ns);
 
 	/* We are in the progress to start a full sync... */
 	if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
@@ -1449,7 +1457,7 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 					drbd_disk_str(device->state.disk));
 
 			if (ns.conn >= C_CONNECTED)
-				drbd_send_state(first_peer_device(device), ns);
+				drbd_send_state(peer_device, ns);
 
 			drbd_rs_cancel_all(device);
 
@@ -1473,7 +1481,7 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 				 drbd_disk_str(device->state.disk));
 
 		if (ns.conn >= C_CONNECTED)
-			drbd_send_state(first_peer_device(device), ns);
+			drbd_send_state(peer_device, ns);
 		/* corresponding get_ldev in __drbd_set_state
 		 * this may finally trigger drbd_ldev_destroy. */
 		put_ldev(device);
@@ -1481,7 +1489,7 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 
 	/* Notify peer that I had a local IO error, and did not detached.. */
 	if (os.disk == D_UP_TO_DATE && ns.disk == D_INCONSISTENT && ns.conn >= C_CONNECTED)
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_state(peer_device, ns);
 
 	/* Disks got bigger while they were detached */
 	if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
@@ -1499,14 +1507,14 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os,
 	/* sync target done with resync.  Explicitly notify peer, even though
 	 * it should (at least for non-empty resyncs) already know itself. */
 	if (os.disk < D_UP_TO_DATE && os.conn >= C_SYNC_SOURCE && ns.conn == C_CONNECTED)
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_state(peer_device, ns);
 
 	/* Verify finished, or reached stop sector.  Peer did not know about
 	 * the stop sector, and we may even have changed the stop sector during
 	 * verify to interrupt/stop early.  Send the new state. */
 	if (os.conn == C_VERIFY_S && ns.conn == C_CONNECTED
 	&& verify_can_do_stop_sector(device))
-		drbd_send_state(first_peer_device(device), ns);
+		drbd_send_state(peer_device, ns);
 
 	/* This triggers bitmap writeout of potentially still unwritten pages
 	 * if the resync finished cleanly, or aborted because of peer disk
@@ -1563,7 +1571,7 @@ static int w_after_conn_state_ch(struct drbd_work *w, int unused)
 		old_conf = connection->net_conf;
 		connection->my_addr_len = 0;
 		connection->peer_addr_len = 0;
-		rcu_assign_pointer(connection->net_conf, NULL);
+		RCU_INIT_POINTER(connection->net_conf, NULL);
 		conn_free_crypto(connection);
 		mutex_unlock(&connection->resource->conf_update);
 
@@ -1599,7 +1607,7 @@ static int w_after_conn_state_ch(struct drbd_work *w, int unused)
 	return 0;
 }
 
-void conn_old_common_state(struct drbd_connection *connection, union drbd_state *pcs, enum chg_state_flags *pf)
+static void conn_old_common_state(struct drbd_connection *connection, union drbd_state *pcs, enum chg_state_flags *pf)
 {
 	enum chg_state_flags flags = ~0;
 	struct drbd_peer_device *peer_device;
@@ -1688,7 +1696,7 @@ conn_is_valid_transition(struct drbd_connection *connection, union drbd_state ma
 	return rv;
 }
 
-void
+static void
 conn_set_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val,
 	       union drbd_state *pns_min, union drbd_state *pns_max, enum chg_state_flags flags)
 {