1 files changed, 216 insertions, 271 deletions

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index e7d0e637e632..91f3b8afb63c 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
+// SPDX-License-Identifier: GPL-2.0-only
 /*
    drbd_nl.c
 
@@ -25,7 +25,7 @@
 #include "drbd_protocol.h"
 #include "drbd_req.h"
 #include "drbd_state_change.h"
-#include <asm/unaligned.h>
+#include <linux/unaligned.h>
 #include <linux/drbd_limits.h>
 #include <linux/kthread.h>
 
@@ -82,7 +82,7 @@ static atomic_t notify_genl_seq = ATOMIC_INIT(2); /* two. */
 
 DEFINE_MUTEX(notification_mutex);
 
-/* used blkdev_get_by_path, to claim our meta data device(s) */
+/* used bdev_open_by_path, to claim our meta data device(s) */
 static char *drbd_m_holder = "Hands off! this is DRBD's meta data device.";
 
 static void drbd_adm_send_reply(struct sk_buff *skb, struct genl_info *info)
@@ -159,7 +159,7 @@ static int drbd_msg_sprintf_info(struct sk_buff *skb, const char *fmt, ...)
 static int drbd_adm_prepare(struct drbd_config_context *adm_ctx,
 	struct sk_buff *skb, struct genl_info *info, unsigned flags)
 {
-	struct drbd_genlmsghdr *d_in = info->userhdr;
+	struct drbd_genlmsghdr *d_in = genl_info_userhdr(info);
 	const u8 cmd = info->genlhdr->cmd;
 	int err;
 
@@ -770,6 +770,7 @@ int drbd_adm_set_role(struct sk_buff *skb, struct genl_info *info)
 	struct set_role_parms parms;
 	int err;
 	enum drbd_ret_code retcode;
+	enum drbd_state_rv rv;
 
 	retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
 	if (!adm_ctx.reply_skb)
@@ -790,14 +791,14 @@ int drbd_adm_set_role(struct sk_buff *skb, struct genl_info *info)
 	mutex_lock(&adm_ctx.resource->adm_mutex);
 
 	if (info->genlhdr->cmd == DRBD_ADM_PRIMARY)
-		retcode = (enum drbd_ret_code)drbd_set_role(adm_ctx.device,
-						R_PRIMARY, parms.assume_uptodate);
+		rv = drbd_set_role(adm_ctx.device, R_PRIMARY, parms.assume_uptodate);
 	else
-		retcode = (enum drbd_ret_code)drbd_set_role(adm_ctx.device,
-						R_SECONDARY, 0);
+		rv = drbd_set_role(adm_ctx.device, R_SECONDARY, 0);
 
 	mutex_unlock(&adm_ctx.resource->adm_mutex);
 	genl_lock();
+	drbd_adm_finish(&adm_ctx, info, rv);
+	return 0;
 out:
 	drbd_adm_finish(&adm_ctx, info, retcode);
 	return 0;
@@ -1032,7 +1033,7 @@ drbd_determine_dev_size(struct drbd_device *device, enum dds_flags flags, struct
 		/* We do some synchronous IO below, which may take some time.
 		 * Clear the timer, to avoid scary "timer expired!" messages,
 		 * "Superblock" is written out at least twice below, anyways. */
-		del_timer(&device->md_sync_timer);
+		timer_delete(&device->md_sync_timer);
 
 		/* We won't change the "al-extents" setting, we just may need
 		 * to move the on-disk location of the activity log ringbuffer.
@@ -1052,7 +1053,7 @@ drbd_determine_dev_size(struct drbd_device *device, enum dds_flags flags, struct
 			 la_size_changed ? "size changed" : "md moved");
 		/* next line implicitly does drbd_suspend_io()+drbd_resume_io() */
 		drbd_bitmap_io(device, md_moved ? &drbd_bm_write_all : &drbd_bm_write,
-			       "size changed", BM_LOCKED_MASK);
+			       "size changed", BM_LOCKED_MASK, NULL);
 
 		/* on-disk bitmap and activity log is authoritative again
 		 * (unless there was an IO error meanwhile...) */
@@ -1188,9 +1189,31 @@ static int drbd_check_al_size(struct drbd_device *device, struct disk_conf *dc)
 	return 0;
 }
 
-static void blk_queue_discard_granularity(struct request_queue *q, unsigned int granularity)
+static unsigned int drbd_max_peer_bio_size(struct drbd_device *device)
 {
-	q->limits.discard_granularity = granularity;
+	/*
+	 * We may ignore peer limits if the peer is modern enough.  From 8.3.8
+	 * onwards the peer can use multiple BIOs for a single peer_request.
+	 */
+	if (device->state.conn < C_WF_REPORT_PARAMS)
+		return device->peer_max_bio_size;
+
+	if (first_peer_device(device)->connection->agreed_pro_version < 94)
+		return min(device->peer_max_bio_size, DRBD_MAX_SIZE_H80_PACKET);
+
+	/*
+	 * Correct old drbd (up to 8.3.7) if it believes it can do more than
+	 * 32KiB.
+	 */
+	if (first_peer_device(device)->connection->agreed_pro_version == 94)
+		return DRBD_MAX_SIZE_H80_PACKET;
+
+	/*
+	 * drbd 8.3.8 onwards, before 8.4.0
+	 */
+	if (first_peer_device(device)->connection->agreed_pro_version < 100)
+		return DRBD_MAX_BIO_SIZE_P95;
+	return DRBD_MAX_BIO_SIZE;
 }
 
 static unsigned int drbd_max_discard_sectors(struct drbd_connection *connection)
@@ -1203,217 +1226,120 @@ static unsigned int drbd_max_discard_sectors(struct drbd_connection *connection)
 	return AL_EXTENT_SIZE >> 9;
 }
 
-static void decide_on_discard_support(struct drbd_device *device,
-			struct request_queue *q,
-			struct request_queue *b,
-			bool discard_zeroes_if_aligned)
+static bool drbd_discard_supported(struct drbd_connection *connection,
+		struct drbd_backing_dev *bdev)
 {
-	/* q = drbd device queue (device->rq_queue)
-	 * b = backing device queue (device->ldev->backing_bdev->bd_disk->queue),
-	 *     or NULL if diskless
-	 */
-	struct drbd_connection *connection = first_peer_device(device)->connection;
-	bool can_do = b ? blk_queue_discard(b) : true;
-
-	if (can_do && connection->cstate >= C_CONNECTED && !(connection->agreed_features & DRBD_FF_TRIM)) {
-		can_do = false;
-		drbd_info(connection, "peer DRBD too old, does not support TRIM: disabling discards\n");
-	}
-	if (can_do) {
-		/* We don't care for the granularity, really.
-		 * Stacking limits below should fix it for the local
-		 * device.  Whether or not it is a suitable granularity
-		 * on the remote device is not our problem, really. If
-		 * you care, you need to use devices with similar
-		 * topology on all peers. */
-		blk_queue_discard_granularity(q, 512);
-		q->limits.max_discard_sectors = drbd_max_discard_sectors(connection);
-		blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
-		q->limits.max_write_zeroes_sectors = drbd_max_discard_sectors(connection);
-	} else {
-		blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q);
-		blk_queue_discard_granularity(q, 0);
-		q->limits.max_discard_sectors = 0;
-		q->limits.max_write_zeroes_sectors = 0;
-	}
-}
+	if (bdev && !bdev_max_discard_sectors(bdev->backing_bdev))
+		return false;
 
-static void fixup_discard_if_not_supported(struct request_queue *q)
-{
-	/* To avoid confusion, if this queue does not support discard, clear
-	 * max_discard_sectors, which is what lsblk -D reports to the user.
-	 * Older kernels got this wrong in "stack limits".
-	 * */
-	if (!blk_queue_discard(q)) {
-		blk_queue_max_discard_sectors(q, 0);
-		blk_queue_discard_granularity(q, 0);
+	if (connection->cstate >= C_CONNECTED &&
+	    !(connection->agreed_features & DRBD_FF_TRIM)) {
+		drbd_info(connection,
+			"peer DRBD too old, does not support TRIM: disabling discards\n");
+		return false;
 	}
-}
 
-static void fixup_write_zeroes(struct drbd_device *device, struct request_queue *q)
-{
-	/* Fixup max_write_zeroes_sectors after blk_stack_limits():
-	 * if we can handle "zeroes" efficiently on the protocol,
-	 * we want to do that, even if our backend does not announce
-	 * max_write_zeroes_sectors itself. */
-	struct drbd_connection *connection = first_peer_device(device)->connection;
-	/* If the peer announces WZEROES support, use it.  Otherwise, rather
-	 * send explicit zeroes than rely on some discard-zeroes-data magic. */
-	if (connection->agreed_features & DRBD_FF_WZEROES)
-		q->limits.max_write_zeroes_sectors = DRBD_MAX_BBIO_SECTORS;
-	else
-		q->limits.max_write_zeroes_sectors = 0;
+	return true;
 }
 
-static void decide_on_write_same_support(struct drbd_device *device,
-			struct request_queue *q,
-			struct request_queue *b, struct o_qlim *o,
-			bool disable_write_same)
+/* This is the workaround for "bio would need to, but cannot, be split" */
+static unsigned int drbd_backing_dev_max_segments(struct drbd_device *device)
 {
-	struct drbd_peer_device *peer_device = first_peer_device(device);
-	struct drbd_connection *connection = peer_device->connection;
-	bool can_do = b ? b->limits.max_write_same_sectors : true;
+	unsigned int max_segments;
 
-	if (can_do && disable_write_same) {
-		can_do = false;
-		drbd_info(peer_device, "WRITE_SAME disabled by config\n");
-	}
-
-	if (can_do && connection->cstate >= C_CONNECTED && !(connection->agreed_features & DRBD_FF_WSAME)) {
-		can_do = false;
-		drbd_info(peer_device, "peer does not support WRITE_SAME\n");
-	}
-
-	if (o) {
-		/* logical block size; queue_logical_block_size(NULL) is 512 */
-		unsigned int peer_lbs = be32_to_cpu(o->logical_block_size);
-		unsigned int me_lbs_b = queue_logical_block_size(b);
-		unsigned int me_lbs = queue_logical_block_size(q);
-
-		if (me_lbs_b != me_lbs) {
-			drbd_warn(device,
-				"logical block size of local backend does not match (drbd:%u, backend:%u); was this a late attach?\n",
-				me_lbs, me_lbs_b);
-			/* rather disable write same than trigger some BUG_ON later in the scsi layer. */
-			can_do = false;
-		}
-		if (me_lbs_b != peer_lbs) {
-			drbd_warn(peer_device, "logical block sizes do not match (me:%u, peer:%u); this may cause problems.\n",
-				me_lbs, peer_lbs);
-			if (can_do) {
-				drbd_dbg(peer_device, "logical block size mismatch: WRITE_SAME disabled.\n");
-				can_do = false;
-			}
-			me_lbs = max(me_lbs, me_lbs_b);
-			/* We cannot change the logical block size of an in-use queue.
-			 * We can only hope that access happens to be properly aligned.
-			 * If not, the peer will likely produce an IO error, and detach. */
-			if (peer_lbs > me_lbs) {
-				if (device->state.role != R_PRIMARY) {
-					blk_queue_logical_block_size(q, peer_lbs);
-					drbd_warn(peer_device, "logical block size set to %u\n", peer_lbs);
-				} else {
-					drbd_warn(peer_device,
-						"current Primary must NOT adjust logical block size (%u -> %u); hope for the best.\n",
-						me_lbs, peer_lbs);
-				}
-			}
-		}
-		if (can_do && !o->write_same_capable) {
-			/* If we introduce an open-coded write-same loop on the receiving side,
-			 * the peer would present itself as "capable". */
-			drbd_dbg(peer_device, "WRITE_SAME disabled (peer device not capable)\n");
-			can_do = false;
-		}
-	}
+	rcu_read_lock();
+	max_segments = rcu_dereference(device->ldev->disk_conf)->max_bio_bvecs;
+	rcu_read_unlock();
 
-	blk_queue_max_write_same_sectors(q, can_do ? DRBD_MAX_BBIO_SECTORS : 0);
+	if (!max_segments)
+		return BLK_MAX_SEGMENTS;
+	return max_segments;
 }
 
-static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backing_dev *bdev,
-				   unsigned int max_bio_size, struct o_qlim *o)
+void drbd_reconsider_queue_parameters(struct drbd_device *device,
+		struct drbd_backing_dev *bdev, struct o_qlim *o)
 {
+	struct drbd_connection *connection =
+		first_peer_device(device)->connection;
 	struct request_queue * const q = device->rq_queue;
-	unsigned int max_hw_sectors = max_bio_size >> 9;
-	unsigned int max_segments = 0;
+	unsigned int now = queue_max_hw_sectors(q) << 9;
+	struct queue_limits lim;
 	struct request_queue *b = NULL;
-	struct disk_conf *dc;
-	bool discard_zeroes_if_aligned = true;
-	bool disable_write_same = false;
+	unsigned int new;
 
 	if (bdev) {
 		b = bdev->backing_bdev->bd_disk->queue;
 
-		max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9);
-		rcu_read_lock();
-		dc = rcu_dereference(device->ldev->disk_conf);
-		max_segments = dc->max_bio_bvecs;
-		discard_zeroes_if_aligned = dc->discard_zeroes_if_aligned;
-		disable_write_same = dc->disable_write_same;
-		rcu_read_unlock();
-
-		blk_set_stacking_limits(&q->limits);
+		device->local_max_bio_size =
+			queue_max_hw_sectors(b) << SECTOR_SHIFT;
 	}
 
-	blk_queue_max_hw_sectors(q, max_hw_sectors);
-	/* This is the workaround for "bio would need to, but cannot, be split" */
-	blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
-	blk_queue_segment_boundary(q, PAGE_SIZE-1);
-	decide_on_discard_support(device, q, b, discard_zeroes_if_aligned);
-	decide_on_write_same_support(device, q, b, o, disable_write_same);
-
-	if (b) {
-		blk_stack_limits(&q->limits, &b->limits, 0);
-		blk_queue_update_readahead(q);
+	/*
+	 * We may later detach and re-attach on a disconnected Primary.  Avoid
+	 * decreasing the value in this case.
+	 *
+	 * We want to store what we know the peer DRBD can handle, not what the
+	 * peer IO backend can handle.
+	 */
+	new = min3(DRBD_MAX_BIO_SIZE, device->local_max_bio_size,
+		max(drbd_max_peer_bio_size(device), device->peer_max_bio_size));
+	if (new != now) {
+		if (device->state.role == R_PRIMARY && new < now)
+			drbd_err(device, "ASSERT FAILED new < now; (%u < %u)\n",
+					new, now);
+		drbd_info(device, "max BIO size = %u\n", new);
 	}
-	fixup_discard_if_not_supported(q);
-	fixup_write_zeroes(device, q);
-}
-
-void drbd_reconsider_queue_parameters(struct drbd_device *device, struct drbd_backing_dev *bdev, struct o_qlim *o)
-{
-	unsigned int now, new, local, peer;
-
-	now = queue_max_hw_sectors(device->rq_queue) << 9;
-	local = device->local_max_bio_size; /* Eventually last known value, from volatile memory */
-	peer = device->peer_max_bio_size; /* Eventually last known value, from meta data */
 
+	lim = queue_limits_start_update(q);
 	if (bdev) {
-		local = queue_max_hw_sectors(bdev->backing_bdev->bd_disk->queue) << 9;
-		device->local_max_bio_size = local;
+		blk_set_stacking_limits(&lim);
+		lim.max_segments = drbd_backing_dev_max_segments(device);
+	} else {
+		lim.max_segments = BLK_MAX_SEGMENTS;
 	}
-	local = min(local, DRBD_MAX_BIO_SIZE);
 
-	/* We may ignore peer limits if the peer is modern enough.
-	   Because new from 8.3.8 onwards the peer can use multiple
-	   BIOs for a single peer_request */
-	if (device->state.conn >= C_WF_REPORT_PARAMS) {
-		if (first_peer_device(device)->connection->agreed_pro_version < 94)
-			peer = min(device->peer_max_bio_size, DRBD_MAX_SIZE_H80_PACKET);
-			/* Correct old drbd (up to 8.3.7) if it believes it can do more than 32KiB */
-		else if (first_peer_device(device)->connection->agreed_pro_version == 94)
-			peer = DRBD_MAX_SIZE_H80_PACKET;
-		else if (first_peer_device(device)->connection->agreed_pro_version < 100)
-			peer = DRBD_MAX_BIO_SIZE_P95;  /* drbd 8.3.8 onwards, before 8.4.0 */
-		else
-			peer = DRBD_MAX_BIO_SIZE;
+	lim.max_hw_sectors = new >> SECTOR_SHIFT;
+	lim.seg_boundary_mask = PAGE_SIZE - 1;
 
-		/* We may later detach and re-attach on a disconnected Primary.
-		 * Avoid this setting to jump back in that case.
-		 * We want to store what we know the peer DRBD can handle,
-		 * not what the peer IO backend can handle. */
-		if (peer > device->peer_max_bio_size)
-			device->peer_max_bio_size = peer;
+	/*
+	 * We don't care for the granularity, really.
+	 *
+	 * Stacking limits below should fix it for the local device.  Whether or
+	 * not it is a suitable granularity on the remote device is not our
+	 * problem, really. If you care, you need to use devices with similar
+	 * topology on all peers.
+	 */
+	if (drbd_discard_supported(connection, bdev)) {
+		lim.discard_granularity = 512;
+		lim.max_hw_discard_sectors =
+			drbd_max_discard_sectors(connection);
+	} else {
+		lim.discard_granularity = 0;
+		lim.max_hw_discard_sectors = 0;
 	}
-	new = min(local, peer);
 
-	if (device->state.role == R_PRIMARY && new < now)
-		drbd_err(device, "ASSERT FAILED new < now; (%u < %u)\n", new, now);
+	if (bdev)
+		blk_stack_limits(&lim, &b->limits, 0);
 
-	if (new != now)
-		drbd_info(device, "max BIO size = %u\n", new);
+	/*
+	 * If we can handle "zeroes" efficiently on the protocol, we want to do
+	 * that, even if our backend does not announce max_write_zeroes_sectors
+	 * itself.
+	 */
+	if (connection->agreed_features & DRBD_FF_WZEROES)
+		lim.max_write_zeroes_sectors = DRBD_MAX_BBIO_SECTORS;
+	else
+		lim.max_write_zeroes_sectors = 0;
+	lim.max_hw_wzeroes_unmap_sectors = 0;
+
+	if ((lim.discard_granularity >> SECTOR_SHIFT) >
+	    lim.max_hw_discard_sectors) {
+		lim.discard_granularity = 0;
+		lim.max_hw_discard_sectors = 0;
+	}
 
-	drbd_setup_queue_param(device, bdev, new, o);
+	if (queue_limits_commit_update(q, &lim))
+		drbd_err(device, "setting new queue limits failed\n");
 }
 
 /* Starts the worker thread */
@@ -1463,8 +1389,9 @@ static void drbd_suspend_al(struct drbd_device *device)
 
 static bool should_set_defaults(struct genl_info *info)
 {
-	unsigned flags = ((struct drbd_genlmsghdr*)info->userhdr)->flags;
-	return 0 != (flags & DRBD_GENL_F_SET_DEFAULTS);
+	struct drbd_genlmsghdr *dh = genl_info_userhdr(info);
+
+	return 0 != (dh->flags & DRBD_GENL_F_SET_DEFAULTS);
 }
 
 static unsigned int drbd_al_extents_max(struct drbd_backing_dev *bdev)
@@ -1505,14 +1432,14 @@ static bool write_ordering_changed(struct disk_conf *a, struct disk_conf *b)
 static void sanitize_disk_conf(struct drbd_device *device, struct disk_conf *disk_conf,
 			       struct drbd_backing_dev *nbc)
 {
-	struct request_queue * const q = nbc->backing_bdev->bd_disk->queue;
+	struct block_device *bdev = nbc->backing_bdev;
 
 	if (disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
 		disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
 	if (disk_conf->al_extents > drbd_al_extents_max(nbc))
 		disk_conf->al_extents = drbd_al_extents_max(nbc);
 
-	if (!blk_queue_discard(q)) {
+	if (!bdev_max_discard_sectors(bdev)) {
 		if (disk_conf->rs_discard_granularity) {
 			disk_conf->rs_discard_granularity = 0; /* disable feature */
 			drbd_info(device, "rs_discard_granularity feature disabled\n");
@@ -1521,16 +1448,19 @@ static void sanitize_disk_conf(struct drbd_device *device, struct disk_conf *dis
 
 	if (disk_conf->rs_discard_granularity) {
 		int orig_value = disk_conf->rs_discard_granularity;
+		sector_t discard_size = bdev_max_discard_sectors(bdev) << 9;
+		unsigned int discard_granularity = bdev_discard_granularity(bdev);
 		int remainder;
 
-		if (q->limits.discard_granularity > disk_conf->rs_discard_granularity)
-			disk_conf->rs_discard_granularity = q->limits.discard_granularity;
+		if (discard_granularity > disk_conf->rs_discard_granularity)
+			disk_conf->rs_discard_granularity = discard_granularity;
 
-		remainder = disk_conf->rs_discard_granularity % q->limits.discard_granularity;
+		remainder = disk_conf->rs_discard_granularity %
+				discard_granularity;
 		disk_conf->rs_discard_granularity += remainder;
 
-		if (disk_conf->rs_discard_granularity > q->limits.max_discard_sectors << 9)
-			disk_conf->rs_discard_granularity = q->limits.max_discard_sectors << 9;
+		if (disk_conf->rs_discard_granularity > discard_size)
+			disk_conf->rs_discard_granularity = discard_size;
 
 		if (disk_conf->rs_discard_granularity != orig_value)
 			drbd_info(device, "rs_discard_granularity changed to %d\n",
@@ -1607,7 +1537,7 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 		goto fail_unlock;
 	}
 
-	if (!expect(new_disk_conf->resync_rate >= 1))
+	if (!expect(device, new_disk_conf->resync_rate >= 1))
 		new_disk_conf->resync_rate = 1;
 
 	sanitize_disk_conf(device, new_disk_conf, device->ldev);
@@ -1666,8 +1596,8 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 	if (write_ordering_changed(old_disk_conf, new_disk_conf))
 		drbd_bump_write_ordering(device->resource, NULL, WO_BDEV_FLUSH);
 
-	if (old_disk_conf->discard_zeroes_if_aligned != new_disk_conf->discard_zeroes_if_aligned
-	||  old_disk_conf->disable_write_same != new_disk_conf->disable_write_same)
+	if (old_disk_conf->discard_zeroes_if_aligned !=
+	    new_disk_conf->discard_zeroes_if_aligned)
 		drbd_reconsider_queue_parameters(device, device->ldev, NULL);
 
 	drbd_md_sync(device);
@@ -1679,8 +1609,7 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 			drbd_send_sync_param(peer_device);
 	}
 
-	synchronize_rcu();
-	kfree(old_disk_conf);
+	kvfree_rcu_mightsleep(old_disk_conf);
 	kfree(old_plan);
 	mod_timer(&device->request_timer, jiffies + HZ);
 	goto success;
@@ -1699,43 +1628,45 @@ success:
 	return 0;
 }
 
-static struct block_device *open_backing_dev(struct drbd_device *device,
+static struct file *open_backing_dev(struct drbd_device *device,
 		const char *bdev_path, void *claim_ptr, bool do_bd_link)
 {
-	struct block_device *bdev;
+	struct file *file;
 	int err = 0;
 
-	bdev = blkdev_get_by_path(bdev_path,
-				  FMODE_READ | FMODE_WRITE | FMODE_EXCL, claim_ptr);
-	if (IS_ERR(bdev)) {
+	file = bdev_file_open_by_path(bdev_path, BLK_OPEN_READ | BLK_OPEN_WRITE,
+				      claim_ptr, NULL);
+	if (IS_ERR(file)) {
 		drbd_err(device, "open(\"%s\") failed with %ld\n",
-				bdev_path, PTR_ERR(bdev));
-		return bdev;
+				bdev_path, PTR_ERR(file));
+		return file;
 	}
 
 	if (!do_bd_link)
-		return bdev;
+		return file;
 
-	err = bd_link_disk_holder(bdev, device->vdisk);
+	err = bd_link_disk_holder(file_bdev(file), device->vdisk);
 	if (err) {
-		blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+		fput(file);
 		drbd_err(device, "bd_link_disk_holder(\"%s\", ...) failed with %d\n",
 				bdev_path, err);
-		bdev = ERR_PTR(err);
+		file = ERR_PTR(err);
 	}
-	return bdev;
+	return file;
 }
 
 static int open_backing_devices(struct drbd_device *device,
 		struct disk_conf *new_disk_conf,
 		struct drbd_backing_dev *nbc)
 {
-	struct block_device *bdev;
+	struct file *file;
 
-	bdev = open_backing_dev(device, new_disk_conf->backing_dev, device, true);
-	if (IS_ERR(bdev))
+	file = open_backing_dev(device, new_disk_conf->backing_dev, device,
+				  true);
+	if (IS_ERR(file))
 		return ERR_OPEN_DISK;
-	nbc->backing_bdev = bdev;
+	nbc->backing_bdev = file_bdev(file);
+	nbc->backing_bdev_file = file;
 
 	/*
 	 * meta_dev_idx >= 0: external fixed size, possibly multiple
@@ -1745,7 +1676,7 @@ static int open_backing_devices(struct drbd_device *device,
 	 * should check it for you already; but if you don't, or
 	 * someone fooled it, we need to double check here)
 	 */
-	bdev = open_backing_dev(device, new_disk_conf->meta_dev,
+	file = open_backing_dev(device, new_disk_conf->meta_dev,
 		/* claim ptr: device, if claimed exclusively; shared drbd_m_holder,
 		 * if potentially shared with other drbd minors */
 			(new_disk_conf->meta_dev_idx < 0) ? (void*)device : (void*)drbd_m_holder,
@@ -1753,20 +1684,21 @@ static int open_backing_devices(struct drbd_device *device,
 		 * as would happen with internal metadata. */
 			(new_disk_conf->meta_dev_idx != DRBD_MD_INDEX_FLEX_INT &&
 			 new_disk_conf->meta_dev_idx != DRBD_MD_INDEX_INTERNAL));
-	if (IS_ERR(bdev))
+	if (IS_ERR(file))
 		return ERR_OPEN_MD_DISK;
-	nbc->md_bdev = bdev;
+	nbc->md_bdev = file_bdev(file);
+	nbc->f_md_bdev = file;
 	return NO_ERROR;
 }
 
-static void close_backing_dev(struct drbd_device *device, struct block_device *bdev,
-	bool do_bd_unlink)
+static void close_backing_dev(struct drbd_device *device,
+		struct file *bdev_file, bool do_bd_unlink)
 {
-	if (!bdev)
+	if (!bdev_file)
 		return;
 	if (do_bd_unlink)
-		bd_unlink_disk_holder(bdev, device->vdisk);
-	blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+		bd_unlink_disk_holder(file_bdev(bdev_file), device->vdisk);
+	fput(bdev_file);
 }
 
 void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *ldev)
@@ -1774,8 +1706,9 @@ void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *
 	if (ldev == NULL)
 		return;
 
-	close_backing_dev(device, ldev->md_bdev, ldev->md_bdev != ldev->backing_bdev);
-	close_backing_dev(device, ldev->backing_bdev, true);
+	close_backing_dev(device, ldev->f_md_bdev,
+			  ldev->md_bdev != ldev->backing_bdev);
+	close_backing_dev(device, ldev->backing_bdev_file, true);
 
 	kfree(ldev->disk_conf);
 	kfree(ldev);
@@ -2092,13 +2025,15 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info)
 		drbd_info(device, "Assuming that all blocks are out of sync "
 		     "(aka FullSync)\n");
 		if (drbd_bitmap_io(device, &drbd_bmio_set_n_write,
-			"set_n_write from attaching", BM_LOCKED_MASK)) {
+			"set_n_write from attaching", BM_LOCKED_MASK,
+			NULL)) {
 			retcode = ERR_IO_MD_DISK;
 			goto force_diskless_dec;
 		}
 	} else {
 		if (drbd_bitmap_io(device, &drbd_bm_read,
-			"read from attaching", BM_LOCKED_MASK)) {
+			"read from attaching", BM_LOCKED_MASK,
+			NULL)) {
 			retcode = ERR_IO_MD_DISK;
 			goto force_diskless_dec;
 		}
@@ -2189,8 +2124,9 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info)
  fail:
 	conn_reconfig_done(connection);
 	if (nbc) {
-		close_backing_dev(device, nbc->md_bdev, nbc->md_bdev != nbc->backing_bdev);
-		close_backing_dev(device, nbc->backing_bdev, true);
+		close_backing_dev(device, nbc->f_md_bdev,
+			  nbc->md_bdev != nbc->backing_bdev);
+		close_backing_dev(device, nbc->backing_bdev_file, true);
 		kfree(nbc);
 	}
 	kfree(new_disk_conf);
@@ -2511,8 +2447,7 @@ int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
 
 	mutex_unlock(&connection->resource->conf_update);
 	mutex_unlock(&connection->data.mutex);
-	synchronize_rcu();
-	kfree(old_net_conf);
+	kvfree_rcu_mightsleep(old_net_conf);
 
 	if (connection->cstate >= C_WF_REPORT_PARAMS) {
 		struct drbd_peer_device *peer_device;
@@ -2570,6 +2505,7 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info)
 	struct drbd_resource *resource;
 	struct drbd_connection *connection;
 	enum drbd_ret_code retcode;
+	enum drbd_state_rv rv;
 	int i;
 	int err;
 
@@ -2689,12 +2625,11 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info)
 	}
 	rcu_read_unlock();
 
-	retcode = (enum drbd_ret_code)conn_request_state(connection,
-					NS(conn, C_UNCONNECTED), CS_VERBOSE);
+	rv = conn_request_state(connection, NS(conn, C_UNCONNECTED), CS_VERBOSE);
 
 	conn_reconfig_done(connection);
 	mutex_unlock(&adm_ctx.resource->adm_mutex);
-	drbd_adm_finish(&adm_ctx, info, retcode);
+	drbd_adm_finish(&adm_ctx, info, rv);
 	return 0;
 
 fail:
@@ -2802,11 +2737,12 @@ int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info)
 
 	mutex_lock(&adm_ctx.resource->adm_mutex);
 	rv = conn_try_disconnect(connection, parms.force_disconnect);
-	if (rv < SS_SUCCESS)
-		retcode = (enum drbd_ret_code)rv;
-	else
-		retcode = NO_ERROR;
 	mutex_unlock(&adm_ctx.resource->adm_mutex);
+	if (rv < SS_SUCCESS) {
+		drbd_adm_finish(&adm_ctx, info, rv);
+		return 0;
+	}
+	retcode = NO_ERROR;
  fail:
 	drbd_adm_finish(&adm_ctx, info, retcode);
 	return 0;
@@ -2925,8 +2861,7 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
 		new_disk_conf->disk_size = (sector_t)rs.resize_size;
 		rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
 		mutex_unlock(&device->resource->conf_update);
-		synchronize_rcu();
-		kfree(old_disk_conf);
+		kvfree_rcu_mightsleep(old_disk_conf);
 		new_disk_conf = NULL;
 	}
 
@@ -3038,7 +2973,7 @@ int drbd_adm_invalidate(struct sk_buff *skb, struct genl_info *info)
 		retcode = drbd_request_state(device, NS(disk, D_INCONSISTENT));
 		if (retcode >= SS_SUCCESS) {
 			if (drbd_bitmap_io(device, &drbd_bmio_set_n_write,
-				"set_n_write from invalidate", BM_LOCKED_MASK))
+				"set_n_write from invalidate", BM_LOCKED_MASK, NULL))
 				retcode = ERR_IO_MD_DISK;
 		}
 	} else
@@ -3071,11 +3006,12 @@ out:
 	return 0;
 }
 
-static int drbd_bmio_set_susp_al(struct drbd_device *device) __must_hold(local)
+static int drbd_bmio_set_susp_al(struct drbd_device *device,
+		struct drbd_peer_device *peer_device) __must_hold(local)
 {
 	int rv;
 
-	rv = drbd_bmio_set_n_write(device);
+	rv = drbd_bmio_set_n_write(device, peer_device);
 	drbd_suspend_al(device);
 	return rv;
 }
@@ -3118,7 +3054,7 @@ int drbd_adm_invalidate_peer(struct sk_buff *skb, struct genl_info *info)
 		if (retcode >= SS_SUCCESS) {
 			if (drbd_bitmap_io(device, &drbd_bmio_set_susp_al,
 				"set_n_write from invalidate_peer",
-				BM_LOCKED_SET_ALLOWED))
+				BM_LOCKED_SET_ALLOWED, NULL))
 				retcode = ERR_IO_MD_DISK;
 		}
 	} else
@@ -4214,7 +4150,7 @@ int drbd_adm_new_c_uuid(struct sk_buff *skb, struct genl_info *info)
 
 	if (args.clear_bm) {
 		err = drbd_bitmap_io(device, &drbd_bmio_clear_n_write,
-			"clear_n_write from new_c_uuid", BM_LOCKED_MASK);
+			"clear_n_write from new_c_uuid", BM_LOCKED_MASK, NULL);
 		if (err) {
 			drbd_err(device, "Writing bitmap failed with %d\n", err);
 			retcode = ERR_IO_MD_DISK;
@@ -4333,7 +4269,7 @@ static void device_to_info(struct device_info *info,
 int drbd_adm_new_minor(struct sk_buff *skb, struct genl_info *info)
 {
 	struct drbd_config_context adm_ctx;
-	struct drbd_genlmsghdr *dh = info->userhdr;
+	struct drbd_genlmsghdr *dh = genl_info_userhdr(info);
 	enum drbd_ret_code retcode;
 
 	retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_RESOURCE);
@@ -4617,7 +4553,7 @@ static int nla_put_notification_header(struct sk_buff *msg,
 	return drbd_notification_header_to_skb(msg, &nh, true);
 }
 
-void notify_resource_state(struct sk_buff *skb,
+int notify_resource_state(struct sk_buff *skb,
 			   unsigned int seq,
 			   struct drbd_resource *resource,
 			   struct resource_info *resource_info,
@@ -4659,16 +4595,17 @@ void notify_resource_state(struct sk_buff *skb,
 		if (err && err != -ESRCH)
 			goto failed;
 	}
-	return;
+	return 0;
 
 nla_put_failure:
 	nlmsg_free(skb);
 failed:
 	drbd_err(resource, "Error %d while broadcasting event. Event seq:%u\n",
 			err, seq);
+	return err;
 }
 
-void notify_device_state(struct sk_buff *skb,
+int notify_device_state(struct sk_buff *skb,
 			 unsigned int seq,
 			 struct drbd_device *device,
 			 struct device_info *device_info,
@@ -4708,16 +4645,17 @@ void notify_device_state(struct sk_buff *skb,
 		if (err && err != -ESRCH)
 			goto failed;
 	}
-	return;
+	return 0;
 
 nla_put_failure:
 	nlmsg_free(skb);
 failed:
 	drbd_err(device, "Error %d while broadcasting event. Event seq:%u\n",
 		 err, seq);
+	return err;
 }
 
-void notify_connection_state(struct sk_buff *skb,
+int notify_connection_state(struct sk_buff *skb,
 			     unsigned int seq,
 			     struct drbd_connection *connection,
 			     struct connection_info *connection_info,
@@ -4757,16 +4695,17 @@ void notify_connection_state(struct sk_buff *skb,
 		if (err && err != -ESRCH)
 			goto failed;
 	}
-	return;
+	return 0;
 
 nla_put_failure:
 	nlmsg_free(skb);
 failed:
 	drbd_err(connection, "Error %d while broadcasting event. Event seq:%u\n",
 		 err, seq);
+	return err;
 }
 
-void notify_peer_device_state(struct sk_buff *skb,
+int notify_peer_device_state(struct sk_buff *skb,
 			      unsigned int seq,
 			      struct drbd_peer_device *peer_device,
 			      struct peer_device_info *peer_device_info,
@@ -4807,13 +4746,14 @@ void notify_peer_device_state(struct sk_buff *skb,
 		if (err && err != -ESRCH)
 			goto failed;
 	}
-	return;
+	return 0;
 
 nla_put_failure:
 	nlmsg_free(skb);
 failed:
 	drbd_err(peer_device, "Error %d while broadcasting event. Event seq:%u\n",
 		 err, seq);
+	return err;
 }
 
 void notify_helper(enum drbd_notification_type type,
@@ -4827,7 +4767,7 @@ void notify_helper(enum drbd_notification_type type,
 	struct drbd_genlmsghdr *dh;
 	int err;
 
-	strlcpy(helper_info.helper_name, name, sizeof(helper_info.helper_name));
+	strscpy(helper_info.helper_name, name, sizeof(helper_info.helper_name));
 	helper_info.helper_name_len = min(strlen(name), sizeof(helper_info.helper_name));
 	helper_info.helper_status = status;
 
@@ -4864,7 +4804,7 @@ fail:
 		 err, seq);
 }
 
-static void notify_initial_state_done(struct sk_buff *skb, unsigned int seq)
+static int notify_initial_state_done(struct sk_buff *skb, unsigned int seq)
 {
 	struct drbd_genlmsghdr *dh;
 	int err;
@@ -4878,11 +4818,12 @@ static void notify_initial_state_done(struct sk_buff *skb, unsigned int seq)
 	if (nla_put_notification_header(skb, NOTIFY_EXISTS))
 		goto nla_put_failure;
 	genlmsg_end(skb, dh);
-	return;
+	return 0;
 
 nla_put_failure:
 	nlmsg_free(skb);
 	pr_err("Error %d sending event. Event seq:%u\n", err, seq);
+	return err;
 }
 
 static void free_state_changes(struct list_head *list)
@@ -4909,6 +4850,7 @@ static int get_initial_state(struct sk_buff *skb, struct netlink_callback *cb)
 	unsigned int seq = cb->args[2];
 	unsigned int n;
 	enum drbd_notification_type flags = 0;
+	int err = 0;
 
 	/* There is no need for taking notification_mutex here: it doesn't
 	   matter if the initial state events mix with later state chage
@@ -4917,32 +4859,32 @@ static int get_initial_state(struct sk_buff *skb, struct netlink_callback *cb)
 
 	cb->args[5]--;
 	if (cb->args[5] == 1) {
-		notify_initial_state_done(skb, seq);
+		err = notify_initial_state_done(skb, seq);
 		goto out;
 	}
 	n = cb->args[4]++;
 	if (cb->args[4] < cb->args[3])
 		flags |= NOTIFY_CONTINUES;
 	if (n < 1) {
-		notify_resource_state_change(skb, seq, state_change->resource,
+		err = notify_resource_state_change(skb, seq, state_change->resource,
 					     NOTIFY_EXISTS | flags);
 		goto next;
 	}
 	n--;
 	if (n < state_change->n_connections) {
-		notify_connection_state_change(skb, seq, &state_change->connections[n],
+		err = notify_connection_state_change(skb, seq, &state_change->connections[n],
 					       NOTIFY_EXISTS | flags);
 		goto next;
 	}
 	n -= state_change->n_connections;
 	if (n < state_change->n_devices) {
-		notify_device_state_change(skb, seq, &state_change->devices[n],
+		err = notify_device_state_change(skb, seq, &state_change->devices[n],
 					   NOTIFY_EXISTS | flags);
 		goto next;
 	}
 	n -= state_change->n_devices;
 	if (n < state_change->n_devices * state_change->n_connections) {
-		notify_peer_device_state_change(skb, seq, &state_change->peer_devices[n],
+		err = notify_peer_device_state_change(skb, seq, &state_change->peer_devices[n],
 						NOTIFY_EXISTS | flags);
 		goto next;
 	}
@@ -4957,7 +4899,10 @@ next:
 		cb->args[4] = 0;
 	}
 out:
-	return skb->len;
+	if (err)
+		return err;
+	else
+		return skb->len;
 }
 
 int drbd_adm_get_initial_state(struct sk_buff *skb, struct netlink_callback *cb)