Initial file dump from open source releaseHEADmaster

1 files changed, 3389 insertions, 0 deletions

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
new file mode 100644
index 00000000..9c37f3d8
--- /dev/null
+++ b/drivers/block/drbd/drbd_nl.c
@@ -0,0 +1,3389 @@
+/*
+   drbd_nl.c
+
+   This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
+
+   Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
+   Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
+   Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
+
+   drbd is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   drbd is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with drbd; see the file COPYING.  If not, write to
+   the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ */
+
+#include <linux/module.h>
+#include <linux/drbd.h>
+#include <linux/in.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/blkpg.h>
+#include <linux/cpumask.h>
+#include "drbd_int.h"
+#include "drbd_req.h"
+#include "drbd_wrappers.h"
+#include <asm/unaligned.h>
+#include <linux/drbd_limits.h>
+#include <linux/kthread.h>
+
+#include <net/genetlink.h>
+
+/* .doit */
+// int drbd_adm_create_resource(struct sk_buff *skb, struct genl_info *info);
+// int drbd_adm_delete_resource(struct sk_buff *skb, struct genl_info *info);
+
+int drbd_adm_add_minor(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info);
+
+int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_del_resource(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_down(struct sk_buff *skb, struct genl_info *info);
+
+int drbd_adm_set_role(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_detach(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_start_ov(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_new_c_uuid(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_invalidate(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_invalidate_peer(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_pause_sync(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_resume_sync(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_suspend_io(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_resume_io(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_outdate(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_resource_opts(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_get_status(struct sk_buff *skb, struct genl_info *info);
+int drbd_adm_get_timeout_type(struct sk_buff *skb, struct genl_info *info);
+/* .dumpit */
+int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb);
+
+#include <linux/drbd_genl_api.h>
+#include "drbd_nla.h"
+#include <linux/genl_magic_func.h>
+
+/* used blkdev_get_by_path, to claim our meta data device(s) */
+static char *drbd_m_holder = "Hands off! this is DRBD's meta data device.";
+
+/* Configuration is strictly serialized, because generic netlink message
+ * processing is strictly serialized by the genl_lock().
+ * Which means we can use one static global drbd_config_context struct.
+ */
+static struct drbd_config_context {
+	/* assigned from drbd_genlmsghdr */
+	unsigned int minor;
+	/* assigned from request attributes, if present */
+	unsigned int volume;
+#define VOLUME_UNSPECIFIED		(-1U)
+	/* pointer into the request skb,
+	 * limited lifetime! */
+	char *resource_name;
+	struct nlattr *my_addr;
+	struct nlattr *peer_addr;
+
+	/* reply buffer */
+	struct sk_buff *reply_skb;
+	/* pointer into reply buffer */
+	struct drbd_genlmsghdr *reply_dh;
+	/* resolved from attributes, if possible */
+	struct drbd_conf *mdev;
+	struct drbd_tconn *tconn;
+} adm_ctx;
+
+static void drbd_adm_send_reply(struct sk_buff *skb, struct genl_info *info)
+{
+	genlmsg_end(skb, genlmsg_data(nlmsg_data(nlmsg_hdr(skb))));
+	if (genlmsg_reply(skb, info))
+		printk(KERN_ERR "drbd: error sending genl reply\n");
+}
+
+/* Used on a fresh "drbd_adm_prepare"d reply_skb, this cannot fail: The only
+ * reason it could fail was no space in skb, and there are 4k available. */
+int drbd_msg_put_info(const char *info)
+{
+	struct sk_buff *skb = adm_ctx.reply_skb;
+	struct nlattr *nla;
+	int err = -EMSGSIZE;
+
+	if (!info || !info[0])
+		return 0;
+
+	nla = nla_nest_start(skb, DRBD_NLA_CFG_REPLY);
+	if (!nla)
+		return err;
+
+	err = nla_put_string(skb, T_info_text, info);
+	if (err) {
+		nla_nest_cancel(skb, nla);
+		return err;
+	} else
+		nla_nest_end(skb, nla);
+	return 0;
+}
+
+/* This would be a good candidate for a "pre_doit" hook,
+ * and per-family private info->pointers.
+ * But we need to stay compatible with older kernels.
+ * If it returns successfully, adm_ctx members are valid.
+ */
+#define DRBD_ADM_NEED_MINOR	1
+#define DRBD_ADM_NEED_RESOURCE	2
+#define DRBD_ADM_NEED_CONNECTION 4
+static int drbd_adm_prepare(struct sk_buff *skb, struct genl_info *info,
+		unsigned flags)
+{
+	struct drbd_genlmsghdr *d_in = info->userhdr;
+	const u8 cmd = info->genlhdr->cmd;
+	int err;
+
+	memset(&adm_ctx, 0, sizeof(adm_ctx));
+
+	/* genl_rcv_msg only checks for CAP_NET_ADMIN on "GENL_ADMIN_PERM" :( */
+	if (cmd != DRBD_ADM_GET_STATUS && !capable(CAP_NET_ADMIN))
+	       return -EPERM;
+
+	adm_ctx.reply_skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!adm_ctx.reply_skb) {
+		err = -ENOMEM;
+		goto fail;
+	}
+
+	adm_ctx.reply_dh = genlmsg_put_reply(adm_ctx.reply_skb,
+					info, &drbd_genl_family, 0, cmd);
+	/* put of a few bytes into a fresh skb of >= 4k will always succeed.
+	 * but anyways */
+	if (!adm_ctx.reply_dh) {
+		err = -ENOMEM;
+		goto fail;
+	}
+
+	adm_ctx.reply_dh->minor = d_in->minor;
+	adm_ctx.reply_dh->ret_code = NO_ERROR;
+
+	adm_ctx.volume = VOLUME_UNSPECIFIED;
+	if (info->attrs[DRBD_NLA_CFG_CONTEXT]) {
+		struct nlattr *nla;
+		/* parse and validate only */
+		err = drbd_cfg_context_from_attrs(NULL, info);
+		if (err)
+			goto fail;
+
+		/* It was present, and valid,
+		 * copy it over to the reply skb. */
+		err = nla_put_nohdr(adm_ctx.reply_skb,
+				info->attrs[DRBD_NLA_CFG_CONTEXT]->nla_len,
+				info->attrs[DRBD_NLA_CFG_CONTEXT]);
+		if (err)
+			goto fail;
+
+		/* and assign stuff to the global adm_ctx */
+		nla = nested_attr_tb[__nla_type(T_ctx_volume)];
+		if (nla)
+			adm_ctx.volume = nla_get_u32(nla);
+		nla = nested_attr_tb[__nla_type(T_ctx_resource_name)];
+		if (nla)
+			adm_ctx.resource_name = nla_data(nla);
+		adm_ctx.my_addr = nested_attr_tb[__nla_type(T_ctx_my_addr)];
+		adm_ctx.peer_addr = nested_attr_tb[__nla_type(T_ctx_peer_addr)];
+		if ((adm_ctx.my_addr &&
+		     nla_len(adm_ctx.my_addr) > sizeof(adm_ctx.tconn->my_addr)) ||
+		    (adm_ctx.peer_addr &&
+		     nla_len(adm_ctx.peer_addr) > sizeof(adm_ctx.tconn->peer_addr))) {
+			err = -EINVAL;
+			goto fail;
+		}
+	}
+
+	adm_ctx.minor = d_in->minor;
+	adm_ctx.mdev = minor_to_mdev(d_in->minor);
+	adm_ctx.tconn = conn_get_by_name(adm_ctx.resource_name);
+
+	if (!adm_ctx.mdev && (flags & DRBD_ADM_NEED_MINOR)) {
+		drbd_msg_put_info("unknown minor");
+		return ERR_MINOR_INVALID;
+	}
+	if (!adm_ctx.tconn && (flags & DRBD_ADM_NEED_RESOURCE)) {
+		drbd_msg_put_info("unknown resource");
+		return ERR_INVALID_REQUEST;
+	}
+
+	if (flags & DRBD_ADM_NEED_CONNECTION) {
+		if (adm_ctx.tconn && !(flags & DRBD_ADM_NEED_RESOURCE)) {
+			drbd_msg_put_info("no resource name expected");
+			return ERR_INVALID_REQUEST;
+		}
+		if (adm_ctx.mdev) {
+			drbd_msg_put_info("no minor number expected");
+			return ERR_INVALID_REQUEST;
+		}
+		if (adm_ctx.my_addr && adm_ctx.peer_addr)
+			adm_ctx.tconn = conn_get_by_addrs(nla_data(adm_ctx.my_addr),
+							  nla_len(adm_ctx.my_addr),
+							  nla_data(adm_ctx.peer_addr),
+							  nla_len(adm_ctx.peer_addr));
+		if (!adm_ctx.tconn) {
+			drbd_msg_put_info("unknown connection");
+			return ERR_INVALID_REQUEST;
+		}
+	}
+
+	/* some more paranoia, if the request was over-determined */
+	if (adm_ctx.mdev && adm_ctx.tconn &&
+	    adm_ctx.mdev->tconn != adm_ctx.tconn) {
+		pr_warning("request: minor=%u, resource=%s; but that minor belongs to connection %s\n",
+				adm_ctx.minor, adm_ctx.resource_name,
+				adm_ctx.mdev->tconn->name);
+		drbd_msg_put_info("minor exists in different resource");
+		return ERR_INVALID_REQUEST;
+	}
+	if (adm_ctx.mdev &&
+	    adm_ctx.volume != VOLUME_UNSPECIFIED &&
+	    adm_ctx.volume != adm_ctx.mdev->vnr) {
+		pr_warning("request: minor=%u, volume=%u; but that minor is volume %u in %s\n",
+				adm_ctx.minor, adm_ctx.volume,
+				adm_ctx.mdev->vnr, adm_ctx.mdev->tconn->name);
+		drbd_msg_put_info("minor exists as different volume");
+		return ERR_INVALID_REQUEST;
+	}
+
+	return NO_ERROR;
+
+fail:
+	nlmsg_free(adm_ctx.reply_skb);
+	adm_ctx.reply_skb = NULL;
+	return err;
+}
+
+static int drbd_adm_finish(struct genl_info *info, int retcode)
+{
+	if (adm_ctx.tconn) {
+		kref_put(&adm_ctx.tconn->kref, &conn_destroy);
+		adm_ctx.tconn = NULL;
+	}
+
+	if (!adm_ctx.reply_skb)
+		return -ENOMEM;
+
+	adm_ctx.reply_dh->ret_code = retcode;
+	drbd_adm_send_reply(adm_ctx.reply_skb, info);
+	return 0;
+}
+
+static void setup_khelper_env(struct drbd_tconn *tconn, char **envp)
+{
+	char *afs;
+
+	/* FIXME: A future version will not allow this case. */
+	if (tconn->my_addr_len == 0 || tconn->peer_addr_len == 0)
+		return;
+
+	switch (((struct sockaddr *)&tconn->peer_addr)->sa_family) {
+	case AF_INET6:
+		afs = "ipv6";
+		snprintf(envp[4], 60, "DRBD_PEER_ADDRESS=%pI6",
+			 &((struct sockaddr_in6 *)&tconn->peer_addr)->sin6_addr);
+		break;
+	case AF_INET:
+		afs = "ipv4";
+		snprintf(envp[4], 60, "DRBD_PEER_ADDRESS=%pI4",
+			 &((struct sockaddr_in *)&tconn->peer_addr)->sin_addr);
+		break;
+	default:
+		afs = "ssocks";
+		snprintf(envp[4], 60, "DRBD_PEER_ADDRESS=%pI4",
+			 &((struct sockaddr_in *)&tconn->peer_addr)->sin_addr);
+	}
+	snprintf(envp[3], 20, "DRBD_PEER_AF=%s", afs);
+}
+
+int drbd_khelper(struct drbd_conf *mdev, char *cmd)
+{
+	char *envp[] = { "HOME=/",
+			"TERM=linux",
+			"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+			 (char[20]) { }, /* address family */
+			 (char[60]) { }, /* address */
+			NULL };
+	char mb[12];
+	char *argv[] = {usermode_helper, cmd, mb, NULL };
+	struct drbd_tconn *tconn = mdev->tconn;
+	struct sib_info sib;
+	int ret;
+
+	if (current == tconn->worker.task)
+		set_bit(CALLBACK_PENDING, &tconn->flags);
+
+	snprintf(mb, 12, "minor-%d", mdev_to_minor(mdev));
+	setup_khelper_env(tconn, envp);
+
+	/* The helper may take some time.
+	 * write out any unsynced meta data changes now */
+	drbd_md_sync(mdev);
+
+	dev_info(DEV, "helper command: %s %s %s\n", usermode_helper, cmd, mb);
+	sib.sib_reason = SIB_HELPER_PRE;
+	sib.helper_name = cmd;
+	drbd_bcast_event(mdev, &sib);
+	ret = call_usermodehelper(usermode_helper, argv, envp, UMH_WAIT_PROC);
+	if (ret)
+		dev_warn(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
+				usermode_helper, cmd, mb,
+				(ret >> 8) & 0xff, ret);
+	else
+		dev_info(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
+				usermode_helper, cmd, mb,
+				(ret >> 8) & 0xff, ret);
+	sib.sib_reason = SIB_HELPER_POST;
+	sib.helper_exit_code = ret;
+	drbd_bcast_event(mdev, &sib);
+
+	if (current == tconn->worker.task)
+		clear_bit(CALLBACK_PENDING, &tconn->flags);
+
+	if (ret < 0) /* Ignore any ERRNOs we got. */
+		ret = 0;
+
+	return ret;
+}
+
+int conn_khelper(struct drbd_tconn *tconn, char *cmd)
+{
+	char *envp[] = { "HOME=/",
+			"TERM=linux",
+			"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+			 (char[20]) { }, /* address family */
+			 (char[60]) { }, /* address */
+			NULL };
+	char *argv[] = {usermode_helper, cmd, tconn->name, NULL };
+	int ret;
+
+	setup_khelper_env(tconn, envp);
+	conn_md_sync(tconn);
+
+	conn_info(tconn, "helper command: %s %s %s\n", usermode_helper, cmd, tconn->name);
+	/* TODO: conn_bcast_event() ?? */
+
+	ret = call_usermodehelper(usermode_helper, argv, envp, UMH_WAIT_PROC);
+	if (ret)
+		conn_warn(tconn, "helper command: %s %s %s exit code %u (0x%x)\n",
+			  usermode_helper, cmd, tconn->name,
+			  (ret >> 8) & 0xff, ret);
+	else
+		conn_info(tconn, "helper command: %s %s %s exit code %u (0x%x)\n",
+			  usermode_helper, cmd, tconn->name,
+			  (ret >> 8) & 0xff, ret);
+	/* TODO: conn_bcast_event() ?? */
+
+	if (ret < 0) /* Ignore any ERRNOs we got. */
+		ret = 0;
+
+	return ret;
+}
+
+static enum drbd_fencing_p highest_fencing_policy(struct drbd_tconn *tconn)
+{
+	enum drbd_fencing_p fp = FP_NOT_AVAIL;
+	struct drbd_conf *mdev;
+	int vnr;
+
+	rcu_read_lock();
+	idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+		if (get_ldev_if_state(mdev, D_CONSISTENT)) {
+			fp = max_t(enum drbd_fencing_p, fp,
+				   rcu_dereference(mdev->ldev->disk_conf)->fencing);
+			put_ldev(mdev);
+		}
+	}
+	rcu_read_unlock();
+
+	return fp;
+}
+
+bool conn_try_outdate_peer(struct drbd_tconn *tconn)
+{
+	union drbd_state mask = { };
+	union drbd_state val = { };
+	enum drbd_fencing_p fp;
+	char *ex_to_string;
+	int r;
+
+	if (tconn->cstate >= C_WF_REPORT_PARAMS) {
+		conn_err(tconn, "Expected cstate < C_WF_REPORT_PARAMS\n");
+		return false;
+	}
+
+	fp = highest_fencing_policy(tconn);
+	switch (fp) {
+	case FP_NOT_AVAIL:
+		conn_warn(tconn, "Not fencing peer, I'm not even Consistent myself.\n");
+		goto out;
+	case FP_DONT_CARE:
+		return true;
+	default: ;
+	}
+
+	r = conn_khelper(tconn, "fence-peer");
+
+	switch ((r>>8) & 0xff) {
+	case 3: /* peer is inconsistent */
+		ex_to_string = "peer is inconsistent or worse";
+		mask.pdsk = D_MASK;
+		val.pdsk = D_INCONSISTENT;
+		break;
+	case 4: /* peer got outdated, or was already outdated */
+		ex_to_string = "peer was fenced";
+		mask.pdsk = D_MASK;
+		val.pdsk = D_OUTDATED;
+		break;
+	case 5: /* peer was down */
+		if (conn_highest_disk(tconn) == D_UP_TO_DATE) {
+			/* we will(have) create(d) a new UUID anyways... */
+			ex_to_string = "peer is unreachable, assumed to be dead";
+			mask.pdsk = D_MASK;
+			val.pdsk = D_OUTDATED;
+		} else {
+			ex_to_string = "peer unreachable, doing nothing since disk != UpToDate";
+		}
+		break;
+	case 6: /* Peer is primary, voluntarily outdate myself.
+		 * This is useful when an unconnected R_SECONDARY is asked to
+		 * become R_PRIMARY, but finds the other peer being active. */
+		ex_to_string = "peer is active";
+		conn_warn(tconn, "Peer is primary, outdating myself.\n");
+		mask.disk = D_MASK;
+		val.disk = D_OUTDATED;
+		break;
+	case 7:
+		if (fp != FP_STONITH)
+			conn_err(tconn, "fence-peer() = 7 && fencing != Stonith !!!\n");
+		ex_to_string = "peer was stonithed";
+		mask.pdsk = D_MASK;
+		val.pdsk = D_OUTDATED;
+		break;
+	default:
+		/* The script is broken ... */
+		conn_err(tconn, "fence-peer helper broken, returned %d\n", (r>>8)&0xff);
+		return false; /* Eventually leave IO frozen */
+	}
+
+	conn_info(tconn, "fence-peer helper returned %d (%s)\n",
+		  (r>>8) & 0xff, ex_to_string);
+
+ out:
+
+	/* Not using
+	   conn_request_state(tconn, mask, val, CS_VERBOSE);
+	   here, because we might were able to re-establish the connection in the
+	   meantime. */
+	spin_lock_irq(&tconn->req_lock);
+	if (tconn->cstate < C_WF_REPORT_PARAMS && !test_bit(STATE_SENT, &tconn->flags))
+		_conn_request_state(tconn, mask, val, CS_VERBOSE);
+	spin_unlock_irq(&tconn->req_lock);
+
+	return conn_highest_pdsk(tconn) <= D_OUTDATED;
+}
+
+static int _try_outdate_peer_async(void *data)
+{
+	struct drbd_tconn *tconn = (struct drbd_tconn *)data;
+
+	conn_try_outdate_peer(tconn);
+
+	kref_put(&tconn->kref, &conn_destroy);
+	return 0;
+}
+
+void conn_try_outdate_peer_async(struct drbd_tconn *tconn)
+{
+	struct task_struct *opa;
+
+	kref_get(&tconn->kref);
+	/* We may just have force_sig()'ed this thread
+	 * to get it out of some blocking network function.
+	 * Clear signals; otherwise kthread_run(), which internally uses
+	 * wait_on_completion_killable(), will mistake our pending signal
+	 * for a new fatal signal and fail. */
+	flush_signals(current);
+	opa = kthread_run(_try_outdate_peer_async, tconn, "drbd_async_h");
+	if (IS_ERR(opa)) {
+		conn_err(tconn, "out of mem, failed to invoke fence-peer helper\n");
+		kref_put(&tconn->kref, &conn_destroy);
+	}
+}
+
+enum drbd_state_rv
+drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, int force)
+{
+	const int max_tries = 4;
+	enum drbd_state_rv rv = SS_UNKNOWN_ERROR;
+	struct net_conf *nc;
+	int try = 0;
+	int forced = 0;
+	union drbd_state mask, val;
+
+	if (new_role == R_PRIMARY)
+		request_ping(mdev->tconn); /* Detect a dead peer ASAP */
+
+	mutex_lock(mdev->state_mutex);
+
+	mask.i = 0; mask.role = R_MASK;
+	val.i  = 0; val.role  = new_role;
+
+	while (try++ < max_tries) {
+		rv = _drbd_request_state(mdev, mask, val, CS_WAIT_COMPLETE);
+
+		/* in case we first succeeded to outdate,
+		 * but now suddenly could establish a connection */
+		if (rv == SS_CW_FAILED_BY_PEER && mask.pdsk != 0) {
+			val.pdsk = 0;
+			mask.pdsk = 0;
+			continue;
+		}
+
+		if (rv == SS_NO_UP_TO_DATE_DISK && force &&
+		    (mdev->state.disk < D_UP_TO_DATE &&
+		     mdev->state.disk >= D_INCONSISTENT)) {
+			mask.disk = D_MASK;
+			val.disk  = D_UP_TO_DATE;
+			forced = 1;
+			continue;
+		}
+
+		if (rv == SS_NO_UP_TO_DATE_DISK &&
+		    mdev->state.disk == D_CONSISTENT && mask.pdsk == 0) {
+			D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
+
+			if (conn_try_outdate_peer(mdev->tconn)) {
+				val.disk = D_UP_TO_DATE;
+				mask.disk = D_MASK;
+			}
+			continue;
+		}
+
+		if (rv == SS_NOTHING_TO_DO)
+			goto out;
+		if (rv == SS_PRIMARY_NOP && mask.pdsk == 0) {
+			if (!conn_try_outdate_peer(mdev->tconn) && force) {
+				dev_warn(DEV, "Forced into split brain situation!\n");
+				mask.pdsk = D_MASK;
+				val.pdsk  = D_OUTDATED;
+
+			}
+			continue;
+		}
+		if (rv == SS_TWO_PRIMARIES) {
+			/* Maybe the peer is detected as dead very soon...
+			   retry at most once more in this case. */
+			int timeo;
+			rcu_read_lock();
+			nc = rcu_dereference(mdev->tconn->net_conf);
+			timeo = nc ? (nc->ping_timeo + 1) * HZ / 10 : 1;
+			rcu_read_unlock();
+			schedule_timeout_interruptible(timeo);
+			if (try < max_tries)
+				try = max_tries - 1;
+			continue;
+		}
+		if (rv < SS_SUCCESS) {
+			rv = _drbd_request_state(mdev, mask, val,
+						CS_VERBOSE + CS_WAIT_COMPLETE);
+			if (rv < SS_SUCCESS)
+				goto out;
+		}
+		break;
+	}
+
+	if (rv < SS_SUCCESS)
+		goto out;
+
+	if (forced)
+		dev_warn(DEV, "Forced to consider local data as UpToDate!\n");
+
+	/* Wait until nothing is on the fly :) */
+	wait_event(mdev->misc_wait, atomic_read(&mdev->ap_pending_cnt) == 0);
+
+	/* FIXME also wait for all pending P_BARRIER_ACK? */
+
+	if (new_role == R_SECONDARY) {
+		set_disk_ro(mdev->vdisk, true);
+		if (get_ldev(mdev)) {
+			mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
+			put_ldev(mdev);
+		}
+	} else {
+		mutex_lock(&mdev->tconn->conf_update);
+		nc = mdev->tconn->net_conf;
+		if (nc)
+			nc->discard_my_data = 0; /* without copy; single bit op is atomic */
+		mutex_unlock(&mdev->tconn->conf_update);
+
+		set_disk_ro(mdev->vdisk, false);
+		if (get_ldev(mdev)) {
+			if (((mdev->state.conn < C_CONNECTED ||
+			       mdev->state.pdsk <= D_FAILED)
+			      && mdev->ldev->md.uuid[UI_BITMAP] == 0) || forced)
+				drbd_uuid_new_current(mdev);
+
+			mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
+			put_ldev(mdev);
+		}
+	}
+
+	/* writeout of activity log covered areas of the bitmap
+	 * to stable storage done in after state change already */
+
+	if (mdev->state.conn >= C_WF_REPORT_PARAMS) {
+		/* if this was forced, we should consider sync */
+		if (forced)
+			drbd_send_uuids(mdev);
+		drbd_send_current_state(mdev);
+	}
+
+	drbd_md_sync(mdev);
+
+	kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
+out:
+	mutex_unlock(mdev->state_mutex);
+	return rv;
+}
+
+static const char *from_attrs_err_to_txt(int err)
+{
+	return	err == -ENOMSG ? "required attribute missing" :
+		err == -EOPNOTSUPP ? "unknown mandatory attribute" :
+		err == -EEXIST ? "can not change invariant setting" :
+		"invalid attribute value";
+}
+
+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;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	memset(&parms, 0, sizeof(parms));
+	if (info->attrs[DRBD_NLA_SET_ROLE_PARMS]) {
+		err = set_role_parms_from_attrs(&parms, info);
+		if (err) {
+			retcode = ERR_MANDATORY_TAG;
+			drbd_msg_put_info(from_attrs_err_to_txt(err));
+			goto out;
+		}
+	}
+
+	if (info->genlhdr->cmd == DRBD_ADM_PRIMARY)
+		retcode = drbd_set_role(adm_ctx.mdev, R_PRIMARY, parms.assume_uptodate);
+	else
+		retcode = drbd_set_role(adm_ctx.mdev, R_SECONDARY, 0);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+/* Initializes the md.*_offset members, so we are able to find
+ * the on disk meta data.
+ *
+ * We currently have two possible layouts:
+ * external:
+ *   |----------- md_size_sect ------------------|
+ *   [ 4k superblock ][ activity log ][  Bitmap  ]
+ *   | al_offset == 8 |
+ *   | bm_offset = al_offset + X      |
+ *  ==> bitmap sectors = md_size_sect - bm_offset
+ *
+ * internal:
+ *            |----------- md_size_sect ------------------|
+ * [data.....][  Bitmap  ][ activity log ][ 4k superblock ]
+ *                        | al_offset < 0 |
+ *            | bm_offset = al_offset - Y |
+ *  ==> bitmap sectors = Y = al_offset - bm_offset
+ *
+ *  Activity log size used to be fixed 32kB,
+ *  but is about to become configurable.
+ */
+static void drbd_md_set_sector_offsets(struct drbd_conf *mdev,
+				       struct drbd_backing_dev *bdev)
+{
+	sector_t md_size_sect = 0;
+	unsigned int al_size_sect = bdev->md.al_size_4k * 8;
+
+	bdev->md.md_offset = drbd_md_ss(bdev);
+
+	switch (bdev->md.meta_dev_idx) {
+	default:
+		/* v07 style fixed size indexed meta data */
+		bdev->md.md_size_sect = MD_128MB_SECT;
+		bdev->md.al_offset = MD_4kB_SECT;
+		bdev->md.bm_offset = MD_4kB_SECT + al_size_sect;
+		break;
+	case DRBD_MD_INDEX_FLEX_EXT:
+		/* just occupy the full device; unit: sectors */
+		bdev->md.md_size_sect = drbd_get_capacity(bdev->md_bdev);
+		bdev->md.al_offset = MD_4kB_SECT;
+		bdev->md.bm_offset = MD_4kB_SECT + al_size_sect;
+		break;
+	case DRBD_MD_INDEX_INTERNAL:
+	case DRBD_MD_INDEX_FLEX_INT:
+		/* al size is still fixed */
+		bdev->md.al_offset = -al_size_sect;
+		/* we need (slightly less than) ~ this much bitmap sectors: */
+		md_size_sect = drbd_get_capacity(bdev->backing_bdev);
+		md_size_sect = ALIGN(md_size_sect, BM_SECT_PER_EXT);
+		md_size_sect = BM_SECT_TO_EXT(md_size_sect);
+		md_size_sect = ALIGN(md_size_sect, 8);
+
+		/* plus the "drbd meta data super block",
+		 * and the activity log; */
+		md_size_sect += MD_4kB_SECT + al_size_sect;
+
+		bdev->md.md_size_sect = md_size_sect;
+		/* bitmap offset is adjusted by 'super' block size */
+		bdev->md.bm_offset   = -md_size_sect + MD_4kB_SECT;
+		break;
+	}
+}
+
+/* input size is expected to be in KB */
+char *ppsize(char *buf, unsigned long long size)
+{
+	/* Needs 9 bytes at max including trailing NUL:
+	 * -1ULL ==> "16384 EB" */
+	static char units[] = { 'K', 'M', 'G', 'T', 'P', 'E' };
+	int base = 0;
+	while (size >= 10000 && base < sizeof(units)-1) {
+		/* shift + round */
+		size = (size >> 10) + !!(size & (1<<9));
+		base++;
+	}
+	sprintf(buf, "%u %cB", (unsigned)size, units[base]);
+
+	return buf;
+}
+
+/* there is still a theoretical deadlock when called from receiver
+ * on an D_INCONSISTENT R_PRIMARY:
+ *  remote READ does inc_ap_bio, receiver would need to receive answer
+ *  packet from remote to dec_ap_bio again.
+ *  receiver receive_sizes(), comes here,
+ *  waits for ap_bio_cnt == 0. -> deadlock.
+ * but this cannot happen, actually, because:
+ *  R_PRIMARY D_INCONSISTENT, and peer's disk is unreachable
+ *  (not connected, or bad/no disk on peer):
+ *  see drbd_fail_request_early, ap_bio_cnt is zero.
+ *  R_PRIMARY D_INCONSISTENT, and C_SYNC_TARGET:
+ *  peer may not initiate a resize.
+ */
+/* Note these are not to be confused with
+ * drbd_adm_suspend_io/drbd_adm_resume_io,
+ * which are (sub) state changes triggered by admin (drbdsetup),
+ * and can be long lived.
+ * This changes an mdev->flag, is triggered by drbd internals,
+ * and should be short-lived. */
+void drbd_suspend_io(struct drbd_conf *mdev)
+{
+	set_bit(SUSPEND_IO, &mdev->flags);
+	if (drbd_suspended(mdev))
+		return;
+	wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
+}
+
+void drbd_resume_io(struct drbd_conf *mdev)
+{
+	clear_bit(SUSPEND_IO, &mdev->flags);
+	wake_up(&mdev->misc_wait);
+}
+
+/**
+ * drbd_determine_dev_size() -  Sets the right device size obeying all constraints
+ * @mdev:	DRBD device.
+ *
+ * Returns 0 on success, negative return values indicate errors.
+ * You should call drbd_md_sync() after calling this function.
+ */
+enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *mdev, enum dds_flags flags) __must_hold(local)
+{
+	sector_t prev_first_sect, prev_size; /* previous meta location */
+	sector_t la_size_sect, u_size;
+	sector_t size;
+	char ppb[10];
+
+	int md_moved, la_size_changed;
+	enum determine_dev_size rv = unchanged;
+
+	/* race:
+	 * application request passes inc_ap_bio,
+	 * but then cannot get an AL-reference.
+	 * this function later may wait on ap_bio_cnt == 0. -> deadlock.
+	 *
+	 * to avoid that:
+	 * Suspend IO right here.
+	 * still lock the act_log to not trigger ASSERTs there.
+	 */
+	drbd_suspend_io(mdev);
+
+	/* no wait necessary anymore, actually we could assert that */
+	wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
+
+	prev_first_sect = drbd_md_first_sector(mdev->ldev);
+	prev_size = mdev->ldev->md.md_size_sect;
+	la_size_sect = mdev->ldev->md.la_size_sect;
+
+	/* TODO: should only be some assert here, not (re)init... */
+	drbd_md_set_sector_offsets(mdev, mdev->ldev);
+
+	rcu_read_lock();
+	u_size = rcu_dereference(mdev->ldev->disk_conf)->disk_size;
+	rcu_read_unlock();
+	size = drbd_new_dev_size(mdev, mdev->ldev, u_size, flags & DDSF_FORCED);
+
+	if (drbd_get_capacity(mdev->this_bdev) != size ||
+	    drbd_bm_capacity(mdev) != size) {
+		int err;
+		err = drbd_bm_resize(mdev, size, !(flags & DDSF_NO_RESYNC));
+		if (unlikely(err)) {
+			/* currently there is only one error: ENOMEM! */
+			size = drbd_bm_capacity(mdev)>>1;
+			if (size == 0) {
+				dev_err(DEV, "OUT OF MEMORY! "
+				    "Could not allocate bitmap!\n");
+			} else {
+				dev_err(DEV, "BM resizing failed. "
+				    "Leaving size unchanged at size = %lu KB\n",
+				    (unsigned long)size);
+			}
+			rv = dev_size_error;
+		}
+		/* racy, see comments above. */
+		drbd_set_my_capacity(mdev, size);
+		mdev->ldev->md.la_size_sect = size;
+		dev_info(DEV, "size = %s (%llu KB)\n", ppsize(ppb, size>>1),
+		     (unsigned long long)size>>1);
+	}
+	if (rv == dev_size_error)
+		goto out;
+
+	la_size_changed = (la_size_sect != mdev->ldev->md.la_size_sect);
+
+	md_moved = prev_first_sect != drbd_md_first_sector(mdev->ldev)
+		|| prev_size	   != mdev->ldev->md.md_size_sect;
+
+	if (la_size_changed || md_moved) {
+		int err;
+
+		drbd_al_shrink(mdev); /* All extents inactive. */
+		dev_info(DEV, "Writing the whole bitmap, %s\n",
+			 la_size_changed && md_moved ? "size changed and md moved" :
+			 la_size_changed ? "size changed" : "md moved");
+		/* next line implicitly does drbd_suspend_io()+drbd_resume_io() */
+		err = drbd_bitmap_io(mdev, md_moved ? &drbd_bm_write_all : &drbd_bm_write,
+				     "size changed", BM_LOCKED_MASK);
+		if (err) {
+			rv = dev_size_error;
+			goto out;
+		}
+		drbd_md_mark_dirty(mdev);
+	}
+
+	if (size > la_size_sect)
+		rv = grew;
+	if (size < la_size_sect)
+		rv = shrunk;
+out:
+	lc_unlock(mdev->act_log);
+	wake_up(&mdev->al_wait);
+	drbd_resume_io(mdev);
+
+	return rv;
+}
+
+sector_t
+drbd_new_dev_size(struct drbd_conf *mdev, struct drbd_backing_dev *bdev,
+		  sector_t u_size, int assume_peer_has_space)
+{
+	sector_t p_size = mdev->p_size;   /* partner's disk size. */
+	sector_t la_size_sect = bdev->md.la_size_sect; /* last agreed size. */
+	sector_t m_size; /* my size */
+	sector_t size = 0;
+
+	m_size = drbd_get_max_capacity(bdev);
+
+	if (mdev->state.conn < C_CONNECTED && assume_peer_has_space) {
+		dev_warn(DEV, "Resize while not connected was forced by the user!\n");
+		p_size = m_size;
+	}
+
+	if (p_size && m_size) {
+		size = min_t(sector_t, p_size, m_size);
+	} else {
+		if (la_size_sect) {
+			size = la_size_sect;
+			if (m_size && m_size < size)
+				size = m_size;
+			if (p_size && p_size < size)
+				size = p_size;
+		} else {
+			if (m_size)
+				size = m_size;
+			if (p_size)
+				size = p_size;
+		}
+	}
+
+	if (size == 0)
+		dev_err(DEV, "Both nodes diskless!\n");
+
+	if (u_size) {
+		if (u_size > size)
+			dev_err(DEV, "Requested disk size is too big (%lu > %lu)\n",
+			    (unsigned long)u_size>>1, (unsigned long)size>>1);
+		else
+			size = u_size;
+	}
+
+	return size;
+}
+
+/**
+ * drbd_check_al_size() - Ensures that the AL is of the right size
+ * @mdev:	DRBD device.
+ *
+ * Returns -EBUSY if current al lru is still used, -ENOMEM when allocation
+ * failed, and 0 on success. You should call drbd_md_sync() after you called
+ * this function.
+ */
+static int drbd_check_al_size(struct drbd_conf *mdev, struct disk_conf *dc)
+{
+	struct lru_cache *n, *t;
+	struct lc_element *e;
+	unsigned int in_use;
+	int i;
+
+	if (mdev->act_log &&
+	    mdev->act_log->nr_elements == dc->al_extents)
+		return 0;
+
+	in_use = 0;
+	t = mdev->act_log;
+	n = lc_create("act_log", drbd_al_ext_cache, AL_UPDATES_PER_TRANSACTION,
+		dc->al_extents, sizeof(struct lc_element), 0);
+
+	if (n == NULL) {
+		dev_err(DEV, "Cannot allocate act_log lru!\n");
+		return -ENOMEM;
+	}
+	spin_lock_irq(&mdev->al_lock);
+	if (t) {
+		for (i = 0; i < t->nr_elements; i++) {
+			e = lc_element_by_index(t, i);
+			if (e->refcnt)
+				dev_err(DEV, "refcnt(%d)==%d\n",
+				    e->lc_number, e->refcnt);
+			in_use += e->refcnt;
+		}
+	}
+	if (!in_use)
+		mdev->act_log = n;
+	spin_unlock_irq(&mdev->al_lock);
+	if (in_use) {
+		dev_err(DEV, "Activity log still in use!\n");
+		lc_destroy(n);
+		return -EBUSY;
+	} else {
+		if (t)
+			lc_destroy(t);
+	}
+	drbd_md_mark_dirty(mdev); /* we changed mdev->act_log->nr_elemens */
+	return 0;
+}
+
+static void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_bio_size)
+{
+	struct request_queue * const q = mdev->rq_queue;
+	unsigned int max_hw_sectors = max_bio_size >> 9;
+	unsigned int max_segments = 0;
+
+	if (get_ldev_if_state(mdev, D_ATTACHING)) {
+		struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
+
+		max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9);
+		rcu_read_lock();
+		max_segments = rcu_dereference(mdev->ldev->disk_conf)->max_bio_bvecs;
+		rcu_read_unlock();
+		put_ldev(mdev);
+	}
+
+	blk_queue_logical_block_size(q, 512);
+	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_CACHE_SIZE-1);
+
+	if (get_ldev_if_state(mdev, D_ATTACHING)) {
+		struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
+
+		blk_queue_stack_limits(q, b);
+
+		if (q->backing_dev_info.ra_pages != b->backing_dev_info.ra_pages) {
+			dev_info(DEV, "Adjusting my ra_pages to backing device's (%lu -> %lu)\n",
+				 q->backing_dev_info.ra_pages,
+				 b->backing_dev_info.ra_pages);
+			q->backing_dev_info.ra_pages = b->backing_dev_info.ra_pages;
+		}
+		put_ldev(mdev);
+	}
+}
+
+void drbd_reconsider_max_bio_size(struct drbd_conf *mdev)
+{
+	unsigned int now, new, local, peer;
+
+	now = queue_max_hw_sectors(mdev->rq_queue) << 9;
+	local = mdev->local_max_bio_size; /* Eventually last known value, from volatile memory */
+	peer = mdev->peer_max_bio_size; /* Eventually last known value, from meta data */
+
+	if (get_ldev_if_state(mdev, D_ATTACHING)) {
+		local = queue_max_hw_sectors(mdev->ldev->backing_bdev->bd_disk->queue) << 9;
+		mdev->local_max_bio_size = local;
+		put_ldev(mdev);
+	}
+	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 (mdev->state.conn >= C_CONNECTED) {
+		if (mdev->tconn->agreed_pro_version < 94)
+			peer = min( mdev->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 (mdev->tconn->agreed_pro_version == 94)
+			peer = DRBD_MAX_SIZE_H80_PACKET;
+		else if (mdev->tconn->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;
+	}
+
+	new = min(local, peer);
+
+	if (mdev->state.role == R_PRIMARY && new < now)
+		dev_err(DEV, "ASSERT FAILED new < now; (%u < %u)\n", new, now);
+
+	if (new != now)
+		dev_info(DEV, "max BIO size = %u\n", new);
+
+	drbd_setup_queue_param(mdev, new);
+}
+
+/* Starts the worker thread */
+static void conn_reconfig_start(struct drbd_tconn *tconn)
+{
+	drbd_thread_start(&tconn->worker);
+	conn_flush_workqueue(tconn);
+}
+
+/* if still unconfigured, stops worker again. */
+static void conn_reconfig_done(struct drbd_tconn *tconn)
+{
+	bool stop_threads;
+	spin_lock_irq(&tconn->req_lock);
+	stop_threads = conn_all_vols_unconf(tconn) &&
+		tconn->cstate == C_STANDALONE;
+	spin_unlock_irq(&tconn->req_lock);
+	if (stop_threads) {
+		/* asender is implicitly stopped by receiver
+		 * in conn_disconnect() */
+		drbd_thread_stop(&tconn->receiver);
+		drbd_thread_stop(&tconn->worker);
+	}
+}
+
+/* Make sure IO is suspended before calling this function(). */
+static void drbd_suspend_al(struct drbd_conf *mdev)
+{
+	int s = 0;
+
+	if (!lc_try_lock(mdev->act_log)) {
+		dev_warn(DEV, "Failed to lock al in drbd_suspend_al()\n");
+		return;
+	}
+
+	drbd_al_shrink(mdev);
+	spin_lock_irq(&mdev->tconn->req_lock);
+	if (mdev->state.conn < C_CONNECTED)
+		s = !test_and_set_bit(AL_SUSPENDED, &mdev->flags);
+	spin_unlock_irq(&mdev->tconn->req_lock);
+	lc_unlock(mdev->act_log);
+
+	if (s)
+		dev_info(DEV, "Suspended AL updates\n");
+}
+
+
+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);
+}
+
+static unsigned int drbd_al_extents_max(struct drbd_backing_dev *bdev)
+{
+	/* This is limited by 16 bit "slot" numbers,
+	 * and by available on-disk context storage.
+	 *
+	 * Also (u16)~0 is special (denotes a "free" extent).
+	 *
+	 * One transaction occupies one 4kB on-disk block,
+	 * we have n such blocks in the on disk ring buffer,
+	 * the "current" transaction may fail (n-1),
+	 * and there is 919 slot numbers context information per transaction.
+	 *
+	 * 72 transaction blocks amounts to more than 2**16 context slots,
+	 * so cap there first.
+	 */
+	const unsigned int max_al_nr = DRBD_AL_EXTENTS_MAX;
+	const unsigned int sufficient_on_disk =
+		(max_al_nr + AL_CONTEXT_PER_TRANSACTION -1)
+		/AL_CONTEXT_PER_TRANSACTION;
+
+	unsigned int al_size_4k = bdev->md.al_size_4k;
+
+	if (al_size_4k > sufficient_on_disk)
+		return max_al_nr;
+
+	return (al_size_4k - 1) * AL_CONTEXT_PER_TRANSACTION;
+}
+
+int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+	struct drbd_conf *mdev;
+	struct disk_conf *new_disk_conf, *old_disk_conf;
+	struct fifo_buffer *old_plan = NULL, *new_plan = NULL;
+	int err, fifo_size;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	mdev = adm_ctx.mdev;
+
+	/* we also need a disk
+	 * to change the options on */
+	if (!get_ldev(mdev)) {
+		retcode = ERR_NO_DISK;
+		goto out;
+	}
+
+	new_disk_conf = kmalloc(sizeof(struct disk_conf), GFP_KERNEL);
+	if (!new_disk_conf) {
+		retcode = ERR_NOMEM;
+		goto fail;
+	}
+
+	mutex_lock(&mdev->tconn->conf_update);
+	old_disk_conf = mdev->ldev->disk_conf;
+	*new_disk_conf = *old_disk_conf;
+	if (should_set_defaults(info))
+		set_disk_conf_defaults(new_disk_conf);
+
+	err = disk_conf_from_attrs_for_change(new_disk_conf, info);
+	if (err && err != -ENOMSG) {
+		retcode = ERR_MANDATORY_TAG;
+		drbd_msg_put_info(from_attrs_err_to_txt(err));
+	}
+
+	if (!expect(new_disk_conf->resync_rate >= 1))
+		new_disk_conf->resync_rate = 1;
+
+	if (new_disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
+		new_disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
+	if (new_disk_conf->al_extents > drbd_al_extents_max(mdev->ldev))
+		new_disk_conf->al_extents = drbd_al_extents_max(mdev->ldev);
+
+	if (new_disk_conf->c_plan_ahead > DRBD_C_PLAN_AHEAD_MAX)
+		new_disk_conf->c_plan_ahead = DRBD_C_PLAN_AHEAD_MAX;
+
+	fifo_size = (new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ;
+	if (fifo_size != mdev->rs_plan_s->size) {
+		new_plan = fifo_alloc(fifo_size);
+		if (!new_plan) {
+			dev_err(DEV, "kmalloc of fifo_buffer failed");
+			retcode = ERR_NOMEM;
+			goto fail_unlock;
+		}
+	}
+
+	drbd_suspend_io(mdev);
+	wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
+	drbd_al_shrink(mdev);
+	err = drbd_check_al_size(mdev, new_disk_conf);
+	lc_unlock(mdev->act_log);
+	wake_up(&mdev->al_wait);
+	drbd_resume_io(mdev);
+
+	if (err) {
+		retcode = ERR_NOMEM;
+		goto fail_unlock;
+	}
+
+	write_lock_irq(&global_state_lock);
+	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_resync_after_changed(mdev);
+	}
+	write_unlock_irq(&global_state_lock);
+
+	if (retcode != NO_ERROR)
+		goto fail_unlock;
+
+	if (new_plan) {
+		old_plan = mdev->rs_plan_s;
+		rcu_assign_pointer(mdev->rs_plan_s, new_plan);
+	}
+
+	mutex_unlock(&mdev->tconn->conf_update);
+
+	if (new_disk_conf->al_updates)
+		mdev->ldev->md.flags &= ~MDF_AL_DISABLED;
+	else
+		mdev->ldev->md.flags |= MDF_AL_DISABLED;
+
+	if (new_disk_conf->md_flushes)
+		clear_bit(MD_NO_FUA, &mdev->flags);
+	else
+		set_bit(MD_NO_FUA, &mdev->flags);
+
+	drbd_bump_write_ordering(mdev->tconn, WO_bdev_flush);
+
+	drbd_md_sync(mdev);
+
+	if (mdev->state.conn >= C_CONNECTED)
+		drbd_send_sync_param(mdev);
+
+	synchronize_rcu();
+	kfree(old_disk_conf);
+	kfree(old_plan);
+	mod_timer(&mdev->request_timer, jiffies + HZ);
+	goto success;
+
+fail_unlock:
+	mutex_unlock(&mdev->tconn->conf_update);
+ fail:
+	kfree(new_disk_conf);
+	kfree(new_plan);
+success:
+	put_ldev(mdev);
+ out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info)
+{
+	struct drbd_conf *mdev;
+	int err;
+	enum drbd_ret_code retcode;
+	enum determine_dev_size dd;
+	sector_t max_possible_sectors;
+	sector_t min_md_device_sectors;
+	struct drbd_backing_dev *nbc = NULL; /* new_backing_conf */
+	struct disk_conf *new_disk_conf = NULL;
+	struct block_device *bdev;
+	struct lru_cache *resync_lru = NULL;
+	struct fifo_buffer *new_plan = NULL;
+	union drbd_state ns, os;
+	enum drbd_state_rv rv;
+	struct net_conf *nc;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto finish;
+
+	mdev = adm_ctx.mdev;
+	conn_reconfig_start(mdev->tconn);
+
+	/* if you want to reconfigure, please tear down first */
+	if (mdev->state.disk > D_DISKLESS) {
+		retcode = ERR_DISK_CONFIGURED;
+		goto fail;
+	}
+	/* It may just now have detached because of IO error.  Make sure
+	 * drbd_ldev_destroy is done already, we may end up here very fast,
+	 * e.g. if someone calls attach from the on-io-error handler,
+	 * to realize a "hot spare" feature (not that I'd recommend that) */
+	wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
+
+	/* make sure there is no leftover from previous force-detach attempts */
+	clear_bit(FORCE_DETACH, &mdev->flags);
+	clear_bit(WAS_IO_ERROR, &mdev->flags);
+	clear_bit(WAS_READ_ERROR, &mdev->flags);
+
+	/* and no leftover from previously aborted resync or verify, either */
+	mdev->rs_total = 0;
+	mdev->rs_failed = 0;
+	atomic_set(&mdev->rs_pending_cnt, 0);
+
+	/* allocation not in the IO path, drbdsetup context */
+	nbc = kzalloc(sizeof(struct drbd_backing_dev), GFP_KERNEL);
+	if (!nbc) {
+		retcode = ERR_NOMEM;
+		goto fail;
+	}
+	spin_lock_init(&nbc->md.uuid_lock);
+
+	new_disk_conf = kzalloc(sizeof(struct disk_conf), GFP_KERNEL);
+	if (!new_disk_conf) {
+		retcode = ERR_NOMEM;
+		goto fail;
+	}
+	nbc->disk_conf = new_disk_conf;
+
+	set_disk_conf_defaults(new_disk_conf);
+	err = disk_conf_from_attrs(new_disk_conf, info);
+	if (err) {
+		retcode = ERR_MANDATORY_TAG;
+		drbd_msg_put_info(from_attrs_err_to_txt(err));
+		goto fail;
+	}
+
+	if (new_disk_conf->c_plan_ahead > DRBD_C_PLAN_AHEAD_MAX)
+		new_disk_conf->c_plan_ahead = DRBD_C_PLAN_AHEAD_MAX;
+
+	new_plan = fifo_alloc((new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ);
+	if (!new_plan) {
+		retcode = ERR_NOMEM;
+		goto fail;
+	}
+
+	if (new_disk_conf->meta_dev_idx < DRBD_MD_INDEX_FLEX_INT) {
+		retcode = ERR_MD_IDX_INVALID;
+		goto fail;
+	}
+
+	write_lock_irq(&global_state_lock);
+	retcode = drbd_resync_after_valid(mdev, new_disk_conf->resync_after);
+	write_unlock_irq(&global_state_lock);
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	rcu_read_lock();
+	nc = rcu_dereference(mdev->tconn->net_conf);
+	if (nc) {
+		if (new_disk_conf->fencing == FP_STONITH && nc->wire_protocol == DRBD_PROT_A) {
+			rcu_read_unlock();
+			retcode = ERR_STONITH_AND_PROT_A;
+			goto fail;
+		}
+	}
+	rcu_read_unlock();
+
+	bdev = blkdev_get_by_path(new_disk_conf->backing_dev,
+				  FMODE_READ | FMODE_WRITE | FMODE_EXCL, mdev);
+	if (IS_ERR(bdev)) {
+		dev_err(DEV, "open(\"%s\") failed with %ld\n", new_disk_conf->backing_dev,
+			PTR_ERR(bdev));
+		retcode = ERR_OPEN_DISK;
+		goto fail;
+	}
+	nbc->backing_bdev = bdev;
+
+	/*
+	 * meta_dev_idx >= 0: external fixed size, possibly multiple
+	 * drbd sharing one meta device.  TODO in that case, paranoia
+	 * check that [md_bdev, meta_dev_idx] is not yet used by some
+	 * other drbd minor!  (if you use drbd.conf + drbdadm, that
+	 * should check it for you already; but if you don't, or
+	 * someone fooled it, we need to double check here)
+	 */
+	bdev = blkdev_get_by_path(new_disk_conf->meta_dev,
+				  FMODE_READ | FMODE_WRITE | FMODE_EXCL,
+				  (new_disk_conf->meta_dev_idx < 0) ?
+				  (void *)mdev : (void *)drbd_m_holder);
+	if (IS_ERR(bdev)) {
+		dev_err(DEV, "open(\"%s\") failed with %ld\n", new_disk_conf->meta_dev,
+			PTR_ERR(bdev));
+		retcode = ERR_OPEN_MD_DISK;
+		goto fail;
+	}
+	nbc->md_bdev = bdev;
+
+	if ((nbc->backing_bdev == nbc->md_bdev) !=
+	    (new_disk_conf->meta_dev_idx == DRBD_MD_INDEX_INTERNAL ||
+	     new_disk_conf->meta_dev_idx == DRBD_MD_INDEX_FLEX_INT)) {
+		retcode = ERR_MD_IDX_INVALID;
+		goto fail;
+	}
+
+	resync_lru = lc_create("resync", drbd_bm_ext_cache,
+			1, 61, sizeof(struct bm_extent),
+			offsetof(struct bm_extent, lce));
+	if (!resync_lru) {
+		retcode = ERR_NOMEM;
+		goto fail;
+	}
+
+	/* Read our meta data super block early.
+	 * This also sets other on-disk offsets. */
+	retcode = drbd_md_read(mdev, nbc);
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	if (new_disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
+		new_disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
+	if (new_disk_conf->al_extents > drbd_al_extents_max(nbc))
+		new_disk_conf->al_extents = drbd_al_extents_max(nbc);
+
+	if (drbd_get_max_capacity(nbc) < new_disk_conf->disk_size) {
+		dev_err(DEV, "max capacity %llu smaller than disk size %llu\n",
+			(unsigned long long) drbd_get_max_capacity(nbc),
+			(unsigned long long) new_disk_conf->disk_size);
+		retcode = ERR_DISK_TOO_SMALL;
+		goto fail;
+	}
+
+	if (new_disk_conf->meta_dev_idx < 0) {
+		max_possible_sectors = DRBD_MAX_SECTORS_FLEX;
+		/* at least one MB, otherwise it does not make sense */
+		min_md_device_sectors = (2<<10);
+	} else {
+		max_possible_sectors = DRBD_MAX_SECTORS;
+		min_md_device_sectors = MD_128MB_SECT * (new_disk_conf->meta_dev_idx + 1);
+	}
+
+	if (drbd_get_capacity(nbc->md_bdev) < min_md_device_sectors) {
+		retcode = ERR_MD_DISK_TOO_SMALL;
+		dev_warn(DEV, "refusing attach: md-device too small, "
+		     "at least %llu sectors needed for this meta-disk type\n",
+		     (unsigned long long) min_md_device_sectors);
+		goto fail;
+	}
+
+	/* Make sure the new disk is big enough
+	 * (we may currently be R_PRIMARY with no local disk...) */
+	if (drbd_get_max_capacity(nbc) <
+	    drbd_get_capacity(mdev->this_bdev)) {
+		retcode = ERR_DISK_TOO_SMALL;
+		goto fail;
+	}
+
+	nbc->known_size = drbd_get_capacity(nbc->backing_bdev);
+
+	if (nbc->known_size > max_possible_sectors) {
+		dev_warn(DEV, "==> truncating very big lower level device "
+			"to currently maximum possible %llu sectors <==\n",
+			(unsigned long long) max_possible_sectors);
+		if (new_disk_conf->meta_dev_idx >= 0)
+			dev_warn(DEV, "==>> using internal or flexible "
+				      "meta data may help <<==\n");
+	}
+
+	drbd_suspend_io(mdev);
+	/* also wait for the last barrier ack. */
+	/* FIXME see also https://daiquiri.linbit/cgi-bin/bugzilla/show_bug.cgi?id=171
+	 * We need a way to either ignore barrier acks for barriers sent before a device
+	 * was attached, or a way to wait for all pending barrier acks to come in.
+	 * As barriers are counted per resource,
+	 * we'd need to suspend io on all devices of a resource.
+	 */
+	wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_pending_cnt) || drbd_suspended(mdev));
+	/* and for any other previously queued work */
+	drbd_flush_workqueue(mdev);
+
+	rv = _drbd_request_state(mdev, NS(disk, D_ATTACHING), CS_VERBOSE);
+	retcode = rv;  /* FIXME: Type mismatch. */
+	drbd_resume_io(mdev);
+	if (rv < SS_SUCCESS)
+		goto fail;
+
+	if (!get_ldev_if_state(mdev, D_ATTACHING))
+		goto force_diskless;
+
+	if (!mdev->bitmap) {
+		if (drbd_bm_init(mdev)) {
+			retcode = ERR_NOMEM;
+			goto force_diskless_dec;
+		}
+	}
+
+	if (mdev->state.conn < C_CONNECTED &&
+	    mdev->state.role == R_PRIMARY &&
+	    (mdev->ed_uuid & ~((u64)1)) != (nbc->md.uuid[UI_CURRENT] & ~((u64)1))) {
+		dev_err(DEV, "Can only attach to data with current UUID=%016llX\n",
+		    (unsigned long long)mdev->ed_uuid);
+		retcode = ERR_DATA_NOT_CURRENT;
+		goto force_diskless_dec;
+	}
+
+	/* Since we are diskless, fix the activity log first... */
+	if (drbd_check_al_size(mdev, new_disk_conf)) {
+		retcode = ERR_NOMEM;
+		goto force_diskless_dec;
+	}
+
+	/* Prevent shrinking of consistent devices ! */
+	if (drbd_md_test_flag(nbc, MDF_CONSISTENT) &&
+	    drbd_new_dev_size(mdev, nbc, nbc->disk_conf->disk_size, 0) < nbc->md.la_size_sect) {
+		dev_warn(DEV, "refusing to truncate a consistent device\n");
+		retcode = ERR_DISK_TOO_SMALL;
+		goto force_diskless_dec;
+	}
+
+	/* Reset the "barriers don't work" bits here, then force meta data to
+	 * be written, to ensure we determine if barriers are supported. */
+	if (new_disk_conf->md_flushes)
+		clear_bit(MD_NO_FUA, &mdev->flags);
+	else
+		set_bit(MD_NO_FUA, &mdev->flags);
+
+	/* Point of no return reached.
+	 * Devices and memory are no longer released by error cleanup below.
+	 * now mdev takes over responsibility, and the state engine should
+	 * clean it up somewhere.  */
+	D_ASSERT(mdev->ldev == NULL);
+	mdev->ldev = nbc;
+	mdev->resync = resync_lru;
+	mdev->rs_plan_s = new_plan;
+	nbc = NULL;
+	resync_lru = NULL;
+	new_disk_conf = NULL;
+	new_plan = NULL;
+
+	drbd_bump_write_ordering(mdev->tconn, WO_bdev_flush);
+
+	if (drbd_md_test_flag(mdev->ldev, MDF_CRASHED_PRIMARY))
+		set_bit(CRASHED_PRIMARY, &mdev->flags);
+	else
+		clear_bit(CRASHED_PRIMARY, &mdev->flags);
+
+	if (drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
+	    !(mdev->state.role == R_PRIMARY && mdev->tconn->susp_nod))
+		set_bit(CRASHED_PRIMARY, &mdev->flags);
+
+	mdev->send_cnt = 0;
+	mdev->recv_cnt = 0;
+	mdev->read_cnt = 0;
+	mdev->writ_cnt = 0;
+
+	drbd_reconsider_max_bio_size(mdev);
+
+	/* If I am currently not R_PRIMARY,
+	 * but meta data primary indicator is set,
+	 * I just now recover from a hard crash,
+	 * and have been R_PRIMARY before that crash.
+	 *
+	 * Now, if I had no connection before that crash
+	 * (have been degraded R_PRIMARY), chances are that
+	 * I won't find my peer now either.
+	 *
+	 * In that case, and _only_ in that case,
+	 * we use the degr-wfc-timeout instead of the default,
+	 * so we can automatically recover from a crash of a
+	 * degraded but active "cluster" after a certain timeout.
+	 */
+	clear_bit(USE_DEGR_WFC_T, &mdev->flags);
+	if (mdev->state.role != R_PRIMARY &&
+	     drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
+	    !drbd_md_test_flag(mdev->ldev, MDF_CONNECTED_IND))
+		set_bit(USE_DEGR_WFC_T, &mdev->flags);
+
+	dd = drbd_determine_dev_size(mdev, 0);
+	if (dd == dev_size_error) {
+		retcode = ERR_NOMEM_BITMAP;
+		goto force_diskless_dec;
+	} else if (dd == grew)
+		set_bit(RESYNC_AFTER_NEG, &mdev->flags);
+
+	if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC) ||
+	    (test_bit(CRASHED_PRIMARY, &mdev->flags) &&
+	     drbd_md_test_flag(mdev->ldev, MDF_AL_DISABLED))) {
+		dev_info(DEV, "Assuming that all blocks are out of sync "
+		     "(aka FullSync)\n");
+		if (drbd_bitmap_io(mdev, &drbd_bmio_set_n_write,
+			"set_n_write from attaching", BM_LOCKED_MASK)) {
+			retcode = ERR_IO_MD_DISK;
+			goto force_diskless_dec;
+		}
+	} else {
+		if (drbd_bitmap_io(mdev, &drbd_bm_read,
+			"read from attaching", BM_LOCKED_MASK)) {
+			retcode = ERR_IO_MD_DISK;
+			goto force_diskless_dec;
+		}
+	}
+
+	if (_drbd_bm_total_weight(mdev) == drbd_bm_bits(mdev))
+		drbd_suspend_al(mdev); /* IO is still suspended here... */
+
+	spin_lock_irq(&mdev->tconn->req_lock);
+	os = drbd_read_state(mdev);
+	ns = os;
+	/* If MDF_CONSISTENT is not set go into inconsistent state,
+	   otherwise investigate MDF_WasUpToDate...
+	   If MDF_WAS_UP_TO_DATE is not set go into D_OUTDATED disk state,
+	   otherwise into D_CONSISTENT state.
+	*/
+	if (drbd_md_test_flag(mdev->ldev, MDF_CONSISTENT)) {
+		if (drbd_md_test_flag(mdev->ldev, MDF_WAS_UP_TO_DATE))
+			ns.disk = D_CONSISTENT;
+		else
+			ns.disk = D_OUTDATED;
+	} else {
+		ns.disk = D_INCONSISTENT;
+	}
+
+	if (drbd_md_test_flag(mdev->ldev, MDF_PEER_OUT_DATED))
+		ns.pdsk = D_OUTDATED;
+
+	rcu_read_lock();
+	if (ns.disk == D_CONSISTENT &&
+	    (ns.pdsk == D_OUTDATED || rcu_dereference(mdev->ldev->disk_conf)->fencing == FP_DONT_CARE))
+		ns.disk = D_UP_TO_DATE;
+
+	/* All tests on MDF_PRIMARY_IND, MDF_CONNECTED_IND,
+	   MDF_CONSISTENT and MDF_WAS_UP_TO_DATE must happen before
+	   this point, because drbd_request_state() modifies these
+	   flags. */
+
+	if (rcu_dereference(mdev->ldev->disk_conf)->al_updates)
+		mdev->ldev->md.flags &= ~MDF_AL_DISABLED;
+	else
+		mdev->ldev->md.flags |= MDF_AL_DISABLED;
+
+	rcu_read_unlock();
+
+	/* In case we are C_CONNECTED postpone any decision on the new disk
+	   state after the negotiation phase. */
+	if (mdev->state.conn == C_CONNECTED) {
+		mdev->new_state_tmp.i = ns.i;
+		ns.i = os.i;
+		ns.disk = D_NEGOTIATING;
+
+		/* We expect to receive up-to-date UUIDs soon.
+		   To avoid a race in receive_state, free p_uuid while
+		   holding req_lock. I.e. atomic with the state change */
+		kfree(mdev->p_uuid);
+		mdev->p_uuid = NULL;
+	}
+
+	rv = _drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
+	spin_unlock_irq(&mdev->tconn->req_lock);
+
+	if (rv < SS_SUCCESS)
+		goto force_diskless_dec;
+
+	mod_timer(&mdev->request_timer, jiffies + HZ);
+
+	if (mdev->state.role == R_PRIMARY)
+		mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
+	else
+		mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
+
+	drbd_md_mark_dirty(mdev);
+	drbd_md_sync(mdev);
+
+	kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
+	put_ldev(mdev);
+	conn_reconfig_done(mdev->tconn);
+	drbd_adm_finish(info, retcode);
+	return 0;
+
+ force_diskless_dec:
+	put_ldev(mdev);
+ force_diskless:
+	drbd_force_state(mdev, NS(disk, D_DISKLESS));
+	drbd_md_sync(mdev);
+ fail:
+	conn_reconfig_done(mdev->tconn);
+	if (nbc) {
+		if (nbc->backing_bdev)
+			blkdev_put(nbc->backing_bdev,
+				   FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+		if (nbc->md_bdev)
+			blkdev_put(nbc->md_bdev,
+				   FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+		kfree(nbc);
+	}
+	kfree(new_disk_conf);
+	lc_destroy(resync_lru);
+	kfree(new_plan);
+
+ finish:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+static int adm_detach(struct drbd_conf *mdev, int force)
+{
+	enum drbd_state_rv retcode;
+	int ret;
+
+	if (force) {
+		set_bit(FORCE_DETACH, &mdev->flags);
+		drbd_force_state(mdev, NS(disk, D_FAILED));
+		retcode = SS_SUCCESS;
+		goto out;
+	}
+
+	drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */
+	drbd_md_get_buffer(mdev); /* make sure there is no in-flight meta-data IO */
+	retcode = drbd_request_state(mdev, NS(disk, D_FAILED));
+	drbd_md_put_buffer(mdev);
+	/* D_FAILED will transition to DISKLESS. */
+	ret = wait_event_interruptible(mdev->misc_wait,
+			mdev->state.disk != D_FAILED);
+	drbd_resume_io(mdev);
+	if ((int)retcode == (int)SS_IS_DISKLESS)
+		retcode = SS_NOTHING_TO_DO;
+	if (ret)
+		retcode = ERR_INTR;
+out:
+	return retcode;
+}
+
+/* Detaching the disk is a process in multiple stages.  First we need to lock
+ * out application IO, in-flight IO, IO stuck in drbd_al_begin_io.
+ * Then we transition to D_DISKLESS, and wait for put_ldev() to return all
+ * internal references as well.
+ * Only then we have finally detached. */
+int drbd_adm_detach(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+	struct detach_parms parms = { };
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	if (info->attrs[DRBD_NLA_DETACH_PARMS]) {
+		err = detach_parms_from_attrs(&parms, info);
+		if (err) {
+			retcode = ERR_MANDATORY_TAG;
+			drbd_msg_put_info(from_attrs_err_to_txt(err));
+			goto out;
+		}
+	}
+
+	retcode = adm_detach(adm_ctx.mdev, parms.force_detach);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+static bool conn_resync_running(struct drbd_tconn *tconn)
+{
+	struct drbd_conf *mdev;
+	bool rv = false;
+	int vnr;
+
+	rcu_read_lock();
+	idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+		if (mdev->state.conn == C_SYNC_SOURCE ||
+		    mdev->state.conn == C_SYNC_TARGET ||
+		    mdev->state.conn == C_PAUSED_SYNC_S ||
+		    mdev->state.conn == C_PAUSED_SYNC_T) {
+			rv = true;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return rv;
+}
+
+static bool conn_ov_running(struct drbd_tconn *tconn)
+{
+	struct drbd_conf *mdev;
+	bool rv = false;
+	int vnr;
+
+	rcu_read_lock();
+	idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+		if (mdev->state.conn == C_VERIFY_S ||
+		    mdev->state.conn == C_VERIFY_T) {
+			rv = true;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return rv;
+}
+
+static enum drbd_ret_code
+_check_net_options(struct drbd_tconn *tconn, struct net_conf *old_conf, struct net_conf *new_conf)
+{
+	struct drbd_conf *mdev;
+	int i;
+
+	if (old_conf && tconn->cstate == C_WF_REPORT_PARAMS && tconn->agreed_pro_version < 100) {
+		if (new_conf->wire_protocol != old_conf->wire_protocol)
+			return ERR_NEED_APV_100;
+
+		if (new_conf->two_primaries != old_conf->two_primaries)
+			return ERR_NEED_APV_100;
+
+		if (strcmp(new_conf->integrity_alg, old_conf->integrity_alg))
+			return ERR_NEED_APV_100;
+	}
+
+	if (!new_conf->two_primaries &&
+	    conn_highest_role(tconn) == R_PRIMARY &&
+	    conn_highest_peer(tconn) == R_PRIMARY)
+		return ERR_NEED_ALLOW_TWO_PRI;
+
+	if (new_conf->two_primaries &&
+	    (new_conf->wire_protocol != DRBD_PROT_C))
+		return ERR_NOT_PROTO_C;
+
+	idr_for_each_entry(&tconn->volumes, mdev, i) {
+		if (get_ldev(mdev)) {
+			enum drbd_fencing_p fp = rcu_dereference(mdev->ldev->disk_conf)->fencing;
+			put_ldev(mdev);
+			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->discard_my_data)
+			return ERR_DISCARD_IMPOSSIBLE;
+	}
+
+	if (new_conf->on_congestion != OC_BLOCK && new_conf->wire_protocol != DRBD_PROT_A)
+		return ERR_CONG_NOT_PROTO_A;
+
+	return NO_ERROR;
+}
+
+static enum drbd_ret_code
+check_net_options(struct drbd_tconn *tconn, struct net_conf *new_conf)
+{
+	static enum drbd_ret_code rv;
+	struct drbd_conf *mdev;
+	int i;
+
+	rcu_read_lock();
+	rv = _check_net_options(tconn, rcu_dereference(tconn->net_conf), new_conf);
+	rcu_read_unlock();
+
+	/* tconn->volumes protected by genl_lock() here */
+	idr_for_each_entry(&tconn->volumes, mdev, i) {
+		if (!mdev->bitmap) {
+			if(drbd_bm_init(mdev))
+				return ERR_NOMEM;
+		}
+	}
+
+	return rv;
+}
+
+struct crypto {
+	struct crypto_hash *verify_tfm;
+	struct crypto_hash *csums_tfm;
+	struct crypto_hash *cram_hmac_tfm;
+	struct crypto_hash *integrity_tfm;
+};
+
+static int
+alloc_hash(struct crypto_hash **tfm, char *tfm_name, int err_alg)
+{
+	if (!tfm_name[0])
+		return NO_ERROR;
+
+	*tfm = crypto_alloc_hash(tfm_name, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(*tfm)) {
+		*tfm = NULL;
+		return err_alg;
+	}
+
+	return NO_ERROR;
+}
+
+static enum drbd_ret_code
+alloc_crypto(struct crypto *crypto, struct net_conf *new_conf)
+{
+	char hmac_name[CRYPTO_MAX_ALG_NAME];
+	enum drbd_ret_code rv;
+
+	rv = alloc_hash(&crypto->csums_tfm, new_conf->csums_alg,
+		       ERR_CSUMS_ALG);
+	if (rv != NO_ERROR)
+		return rv;
+	rv = alloc_hash(&crypto->verify_tfm, new_conf->verify_alg,
+		       ERR_VERIFY_ALG);
+	if (rv != NO_ERROR)
+		return rv;
+	rv = alloc_hash(&crypto->integrity_tfm, new_conf->integrity_alg,
+		       ERR_INTEGRITY_ALG);
+	if (rv != NO_ERROR)
+		return rv;
+	if (new_conf->cram_hmac_alg[0] != 0) {
+		snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",
+			 new_conf->cram_hmac_alg);
+
+		rv = alloc_hash(&crypto->cram_hmac_tfm, hmac_name,
+			       ERR_AUTH_ALG);
+	}
+
+	return rv;
+}
+
+static void free_crypto(struct crypto *crypto)
+{
+	crypto_free_hash(crypto->cram_hmac_tfm);
+	crypto_free_hash(crypto->integrity_tfm);
+	crypto_free_hash(crypto->csums_tfm);
+	crypto_free_hash(crypto->verify_tfm);
+}
+
+int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+	struct drbd_tconn *tconn;
+	struct net_conf *old_conf, *new_conf = NULL;
+	int err;
+	int ovr; /* online verify running */
+	int rsr; /* re-sync running */
+	struct crypto crypto = { };
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_CONNECTION);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	tconn = adm_ctx.tconn;
+
+	new_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
+	if (!new_conf) {
+		retcode = ERR_NOMEM;
+		goto out;
+	}
+
+	conn_reconfig_start(tconn);
+
+	mutex_lock(&tconn->data.mutex);
+	mutex_lock(&tconn->conf_update);
+	old_conf = tconn->net_conf;
+
+	if (!old_conf) {
+		drbd_msg_put_info("net conf missing, try connect");
+		retcode = ERR_INVALID_REQUEST;
+		goto fail;
+	}
+
+	*new_conf = *old_conf;
+	if (should_set_defaults(info))
+		set_net_conf_defaults(new_conf);
+
+	err = net_conf_from_attrs_for_change(new_conf, info);
+	if (err && err != -ENOMSG) {
+		retcode = ERR_MANDATORY_TAG;
+		drbd_msg_put_info(from_attrs_err_to_txt(err));
+		goto fail;
+	}
+
+	retcode = check_net_options(tconn, new_conf);
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	/* re-sync running */
+	rsr = conn_resync_running(tconn);
+	if (rsr && strcmp(new_conf->csums_alg, old_conf->csums_alg)) {
+		retcode = ERR_CSUMS_RESYNC_RUNNING;
+		goto fail;
+	}
+
+	/* online verify running */
+	ovr = conn_ov_running(tconn);
+	if (ovr && strcmp(new_conf->verify_alg, old_conf->verify_alg)) {
+		retcode = ERR_VERIFY_RUNNING;
+		goto fail;
+	}
+
+	retcode = alloc_crypto(&crypto, new_conf);
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	rcu_assign_pointer(tconn->net_conf, new_conf);
+
+	if (!rsr) {
+		crypto_free_hash(tconn->csums_tfm);
+		tconn->csums_tfm = crypto.csums_tfm;
+		crypto.csums_tfm = NULL;
+	}
+	if (!ovr) {
+		crypto_free_hash(tconn->verify_tfm);
+		tconn->verify_tfm = crypto.verify_tfm;
+		crypto.verify_tfm = NULL;
+	}
+
+	crypto_free_hash(tconn->integrity_tfm);
+	tconn->integrity_tfm = crypto.integrity_tfm;
+	if (tconn->cstate >= C_WF_REPORT_PARAMS && tconn->agreed_pro_version >= 100)
+		/* Do this without trying to take tconn->data.mutex again.  */
+		__drbd_send_protocol(tconn, P_PROTOCOL_UPDATE);
+
+	crypto_free_hash(tconn->cram_hmac_tfm);
+	tconn->cram_hmac_tfm = crypto.cram_hmac_tfm;
+
+	mutex_unlock(&tconn->conf_update);
+	mutex_unlock(&tconn->data.mutex);
+	synchronize_rcu();
+	kfree(old_conf);
+
+	if (tconn->cstate >= C_WF_REPORT_PARAMS)
+		drbd_send_sync_param(minor_to_mdev(conn_lowest_minor(tconn)));
+
+	goto done;
+
+ fail:
+	mutex_unlock(&tconn->conf_update);
+	mutex_unlock(&tconn->data.mutex);
+	free_crypto(&crypto);
+	kfree(new_conf);
+ done:
+	conn_reconfig_done(tconn);
+ out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info)
+{
+	struct drbd_conf *mdev;
+	struct net_conf *old_conf, *new_conf = NULL;
+	struct crypto crypto = { };
+	struct drbd_tconn *tconn;
+	enum drbd_ret_code retcode;
+	int i;
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_RESOURCE);
+
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+	if (!(adm_ctx.my_addr && adm_ctx.peer_addr)) {
+		drbd_msg_put_info("connection endpoint(s) missing");
+		retcode = ERR_INVALID_REQUEST;
+		goto out;
+	}
+
+	/* 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(tconn, &drbd_tconns, all_tconn) {
+		if (nla_len(adm_ctx.my_addr) == tconn->my_addr_len &&
+		    !memcmp(nla_data(adm_ctx.my_addr), &tconn->my_addr, tconn->my_addr_len)) {
+			retcode = ERR_LOCAL_ADDR;
+			goto out;
+		}
+
+		if (nla_len(adm_ctx.peer_addr) == tconn->peer_addr_len &&
+		    !memcmp(nla_data(adm_ctx.peer_addr), &tconn->peer_addr, tconn->peer_addr_len)) {
+			retcode = ERR_PEER_ADDR;
+			goto out;
+		}
+	}
+
+	tconn = adm_ctx.tconn;
+	conn_reconfig_start(tconn);
+
+	if (tconn->cstate > C_STANDALONE) {
+		retcode = ERR_NET_CONFIGURED;
+		goto fail;
+	}
+
+	/* allocation not in the IO path, drbdsetup / netlink process context */
+	new_conf = kzalloc(sizeof(*new_conf), GFP_KERNEL);
+	if (!new_conf) {
+		retcode = ERR_NOMEM;
+		goto fail;
+	}
+
+	set_net_conf_defaults(new_conf);
+
+	err = net_conf_from_attrs(new_conf, info);
+	if (err && err != -ENOMSG) {
+		retcode = ERR_MANDATORY_TAG;
+		drbd_msg_put_info(from_attrs_err_to_txt(err));
+		goto fail;
+	}
+
+	retcode = check_net_options(tconn, new_conf);
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	retcode = alloc_crypto(&crypto, new_conf);
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	((char *)new_conf->shared_secret)[SHARED_SECRET_MAX-1] = 0;
+
+	conn_flush_workqueue(tconn);
+
+	mutex_lock(&tconn->conf_update);
+	old_conf = tconn->net_conf;
+	if (old_conf) {
+		retcode = ERR_NET_CONFIGURED;
+		mutex_unlock(&tconn->conf_update);
+		goto fail;
+	}
+	rcu_assign_pointer(tconn->net_conf, new_conf);
+
+	conn_free_crypto(tconn);
+	tconn->cram_hmac_tfm = crypto.cram_hmac_tfm;
+	tconn->integrity_tfm = crypto.integrity_tfm;
+	tconn->csums_tfm = crypto.csums_tfm;
+	tconn->verify_tfm = crypto.verify_tfm;
+
+	tconn->my_addr_len = nla_len(adm_ctx.my_addr);
+	memcpy(&tconn->my_addr, nla_data(adm_ctx.my_addr), tconn->my_addr_len);
+	tconn->peer_addr_len = nla_len(adm_ctx.peer_addr);
+	memcpy(&tconn->peer_addr, nla_data(adm_ctx.peer_addr), tconn->peer_addr_len);
+
+	mutex_unlock(&tconn->conf_update);
+
+	rcu_read_lock();
+	idr_for_each_entry(&tconn->volumes, mdev, i) {
+		mdev->send_cnt = 0;
+		mdev->recv_cnt = 0;
+	}
+	rcu_read_unlock();
+
+	retcode = conn_request_state(tconn, NS(conn, C_UNCONNECTED), CS_VERBOSE);
+
+	conn_reconfig_done(tconn);
+	drbd_adm_finish(info, retcode);
+	return 0;
+
+fail:
+	free_crypto(&crypto);
+	kfree(new_conf);
+
+	conn_reconfig_done(tconn);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+static enum drbd_state_rv conn_try_disconnect(struct drbd_tconn *tconn, bool force)
+{
+	enum drbd_state_rv rv;
+
+	rv = conn_request_state(tconn, NS(conn, C_DISCONNECTING),
+			force ? CS_HARD : 0);
+
+	switch (rv) {
+	case SS_NOTHING_TO_DO:
+		break;
+	case SS_ALREADY_STANDALONE:
+		return SS_SUCCESS;
+	case SS_PRIMARY_NOP:
+		/* Our state checking code wants to see the peer outdated. */
+		rv = conn_request_state(tconn, NS2(conn, C_DISCONNECTING, pdsk, D_OUTDATED), 0);
+
+		if (rv == SS_OUTDATE_WO_CONN) /* lost connection before graceful disconnect succeeded */
+			rv = conn_request_state(tconn, NS(conn, C_DISCONNECTING), CS_VERBOSE);
+
+		break;
+	case SS_CW_FAILED_BY_PEER:
+		/* The peer probably wants to see us outdated. */
+		rv = conn_request_state(tconn, NS2(conn, C_DISCONNECTING,
+							disk, D_OUTDATED), 0);
+		if (rv == SS_IS_DISKLESS || rv == SS_LOWER_THAN_OUTDATED) {
+			rv = conn_request_state(tconn, NS(conn, C_DISCONNECTING),
+					CS_HARD);
+		}
+		break;
+	default:;
+		/* no special handling necessary */
+	}
+
+	if (rv >= SS_SUCCESS) {
+		enum drbd_state_rv rv2;
+		/* No one else can reconfigure the network while I am here.
+		 * The state handling only uses drbd_thread_stop_nowait(),
+		 * we want to really wait here until the receiver is no more.
+		 */
+		drbd_thread_stop(&adm_ctx.tconn->receiver);
+
+		/* Race breaker.  This additional state change request may be
+		 * necessary, if this was a forced disconnect during a receiver
+		 * restart.  We may have "killed" the receiver thread just
+		 * after drbdd_init() returned.  Typically, we should be
+		 * C_STANDALONE already, now, and this becomes a no-op.
+		 */
+		rv2 = conn_request_state(tconn, NS(conn, C_STANDALONE),
+				CS_VERBOSE | CS_HARD);
+		if (rv2 < SS_SUCCESS)
+			conn_err(tconn,
+				"unexpected rv2=%d in conn_try_disconnect()\n",
+				rv2);
+	}
+	return rv;
+}
+
+int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info)
+{
+	struct disconnect_parms parms;
+	struct drbd_tconn *tconn;
+	enum drbd_state_rv rv;
+	enum drbd_ret_code retcode;
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_CONNECTION);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	tconn = adm_ctx.tconn;
+	memset(&parms, 0, sizeof(parms));
+	if (info->attrs[DRBD_NLA_DISCONNECT_PARMS]) {
+		err = disconnect_parms_from_attrs(&parms, info);
+		if (err) {
+			retcode = ERR_MANDATORY_TAG;
+			drbd_msg_put_info(from_attrs_err_to_txt(err));
+			goto fail;
+		}
+	}
+
+	rv = conn_try_disconnect(tconn, parms.force_disconnect);
+	if (rv < SS_SUCCESS)
+		retcode = rv;  /* FIXME: Type mismatch. */
+	else
+		retcode = NO_ERROR;
+ fail:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+void resync_after_online_grow(struct drbd_conf *mdev)
+{
+	int iass; /* I am sync source */
+
+	dev_info(DEV, "Resync of new storage after online grow\n");
+	if (mdev->state.role != mdev->state.peer)
+		iass = (mdev->state.role == R_PRIMARY);
+	else
+		iass = test_bit(RESOLVE_CONFLICTS, &mdev->tconn->flags);
+
+	if (iass)
+		drbd_start_resync(mdev, C_SYNC_SOURCE);
+	else
+		_drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE + CS_SERIALIZE);
+}
+
+int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
+{
+	struct disk_conf *old_disk_conf, *new_disk_conf = NULL;
+	struct resize_parms rs;
+	struct drbd_conf *mdev;
+	enum drbd_ret_code retcode;
+	enum determine_dev_size dd;
+	enum dds_flags ddsf;
+	sector_t u_size;
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto fail;
+
+	memset(&rs, 0, sizeof(struct resize_parms));
+	if (info->attrs[DRBD_NLA_RESIZE_PARMS]) {
+		err = resize_parms_from_attrs(&rs, info);
+		if (err) {
+			retcode = ERR_MANDATORY_TAG;
+			drbd_msg_put_info(from_attrs_err_to_txt(err));
+			goto fail;
+		}
+	}
+
+	mdev = adm_ctx.mdev;
+	if (mdev->state.conn > C_CONNECTED) {
+		retcode = ERR_RESIZE_RESYNC;
+		goto fail;
+	}
+
+	if (mdev->state.role == R_SECONDARY &&
+	    mdev->state.peer == R_SECONDARY) {
+		retcode = ERR_NO_PRIMARY;
+		goto fail;
+	}
+
+	if (!get_ldev(mdev)) {
+		retcode = ERR_NO_DISK;
+		goto fail;
+	}
+
+	if (rs.no_resync && mdev->tconn->agreed_pro_version < 93) {
+		retcode = ERR_NEED_APV_93;
+		goto fail_ldev;
+	}
+
+	rcu_read_lock();
+	u_size = rcu_dereference(mdev->ldev->disk_conf)->disk_size;
+	rcu_read_unlock();
+	if (u_size != (sector_t)rs.resize_size) {
+		new_disk_conf = kmalloc(sizeof(struct disk_conf), GFP_KERNEL);
+		if (!new_disk_conf) {
+			retcode = ERR_NOMEM;
+			goto fail_ldev;
+		}
+	}
+
+	if (mdev->ldev->known_size != drbd_get_capacity(mdev->ldev->backing_bdev))
+		mdev->ldev->known_size = drbd_get_capacity(mdev->ldev->backing_bdev);
+
+	if (new_disk_conf) {
+		mutex_lock(&mdev->tconn->conf_update);
+		old_disk_conf = mdev->ldev->disk_conf;
+		*new_disk_conf = *old_disk_conf;
+		new_disk_conf->disk_size = (sector_t)rs.resize_size;
+		rcu_assign_pointer(mdev->ldev->disk_conf, new_disk_conf);
+		mutex_unlock(&mdev->tconn->conf_update);
+		synchronize_rcu();
+		kfree(old_disk_conf);
+	}
+
+	ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
+	dd = drbd_determine_dev_size(mdev, ddsf);
+	drbd_md_sync(mdev);
+	put_ldev(mdev);
+	if (dd == dev_size_error) {
+		retcode = ERR_NOMEM_BITMAP;
+		goto fail;
+	}
+
+	if (mdev->state.conn == C_CONNECTED) {
+		if (dd == grew)
+			set_bit(RESIZE_PENDING, &mdev->flags);
+
+		drbd_send_uuids(mdev);
+		drbd_send_sizes(mdev, 1, ddsf);
+	}
+
+ fail:
+	drbd_adm_finish(info, retcode);
+	return 0;
+
+ fail_ldev:
+	put_ldev(mdev);
+	goto fail;
+}
+
+int drbd_adm_resource_opts(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+	struct drbd_tconn *tconn;
+	struct res_opts res_opts;
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_RESOURCE);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto fail;
+	tconn = adm_ctx.tconn;
+
+	res_opts = tconn->res_opts;
+	if (should_set_defaults(info))
+		set_res_opts_defaults(&res_opts);
+
+	err = res_opts_from_attrs(&res_opts, info);
+	if (err && err != -ENOMSG) {
+		retcode = ERR_MANDATORY_TAG;
+		drbd_msg_put_info(from_attrs_err_to_txt(err));
+		goto fail;
+	}
+
+	err = set_resource_options(tconn, &res_opts);
+	if (err) {
+		retcode = ERR_INVALID_REQUEST;
+		if (err == -ENOMEM)
+			retcode = ERR_NOMEM;
+	}
+
+fail:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_invalidate(struct sk_buff *skb, struct genl_info *info)
+{
+	struct drbd_conf *mdev;
+	int retcode; /* enum drbd_ret_code rsp. enum drbd_state_rv */
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	mdev = adm_ctx.mdev;
+
+	/* If there is still bitmap IO pending, probably because of a previous
+	 * resync just being finished, wait for it before requesting a new resync.
+	 * Also wait for it's after_state_ch(). */
+	drbd_suspend_io(mdev);
+	wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
+	drbd_flush_workqueue(mdev);
+
+	/* If we happen to be C_STANDALONE R_SECONDARY, just change to
+	 * D_INCONSISTENT, and set all bits in the bitmap.  Otherwise,
+	 * try to start a resync handshake as sync target for full sync.
+	 */
+	if (mdev->state.conn == C_STANDALONE && mdev->state.role == R_SECONDARY) {
+		retcode = drbd_request_state(mdev, NS(disk, D_INCONSISTENT));
+		if (retcode >= SS_SUCCESS) {
+			if (drbd_bitmap_io(mdev, &drbd_bmio_set_n_write,
+				"set_n_write from invalidate", BM_LOCKED_MASK))
+				retcode = ERR_IO_MD_DISK;
+		}
+	} else
+		retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
+	drbd_resume_io(mdev);
+
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+static int drbd_adm_simple_request_state(struct sk_buff *skb, struct genl_info *info,
+		union drbd_state mask, union drbd_state val)
+{
+	enum drbd_ret_code retcode;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	retcode = drbd_request_state(adm_ctx.mdev, mask, val);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+static int drbd_bmio_set_susp_al(struct drbd_conf *mdev)
+{
+	int rv;
+
+	rv = drbd_bmio_set_n_write(mdev);
+	drbd_suspend_al(mdev);
+	return rv;
+}
+
+int drbd_adm_invalidate_peer(struct sk_buff *skb, struct genl_info *info)
+{
+	int retcode; /* drbd_ret_code, drbd_state_rv */
+	struct drbd_conf *mdev;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	mdev = adm_ctx.mdev;
+
+	/* If there is still bitmap IO pending, probably because of a previous
+	 * resync just being finished, wait for it before requesting a new resync.
+	 * Also wait for it's after_state_ch(). */
+	drbd_suspend_io(mdev);
+	wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
+	drbd_flush_workqueue(mdev);
+
+	/* If we happen to be C_STANDALONE R_PRIMARY, just set all bits
+	 * in the bitmap.  Otherwise, try to start a resync handshake
+	 * as sync source for full sync.
+	 */
+	if (mdev->state.conn == C_STANDALONE && mdev->state.role == R_PRIMARY) {
+		/* The peer will get a resync upon connect anyways. Just make that
+		   into a full resync. */
+		retcode = drbd_request_state(mdev, NS(pdsk, D_INCONSISTENT));
+		if (retcode >= SS_SUCCESS) {
+			if (drbd_bitmap_io(mdev, &drbd_bmio_set_susp_al,
+				"set_n_write from invalidate_peer",
+				BM_LOCKED_SET_ALLOWED))
+				retcode = ERR_IO_MD_DISK;
+		}
+	} else
+		retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S));
+	drbd_resume_io(mdev);
+
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_pause_sync(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	if (drbd_request_state(adm_ctx.mdev, NS(user_isp, 1)) == SS_NOTHING_TO_DO)
+		retcode = ERR_PAUSE_IS_SET;
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_resume_sync(struct sk_buff *skb, struct genl_info *info)
+{
+	union drbd_dev_state s;
+	enum drbd_ret_code retcode;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	if (drbd_request_state(adm_ctx.mdev, NS(user_isp, 0)) == SS_NOTHING_TO_DO) {
+		s = adm_ctx.mdev->state;
+		if (s.conn == C_PAUSED_SYNC_S || s.conn == C_PAUSED_SYNC_T) {
+			retcode = s.aftr_isp ? ERR_PIC_AFTER_DEP :
+				  s.peer_isp ? ERR_PIC_PEER_DEP : ERR_PAUSE_IS_CLEAR;
+		} else {
+			retcode = ERR_PAUSE_IS_CLEAR;
+		}
+	}
+
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_suspend_io(struct sk_buff *skb, struct genl_info *info)
+{
+	return drbd_adm_simple_request_state(skb, info, NS(susp, 1));
+}
+
+int drbd_adm_resume_io(struct sk_buff *skb, struct genl_info *info)
+{
+	struct drbd_conf *mdev;
+	int retcode; /* enum drbd_ret_code rsp. enum drbd_state_rv */
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	mdev = adm_ctx.mdev;
+	if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
+		drbd_uuid_new_current(mdev);
+		clear_bit(NEW_CUR_UUID, &mdev->flags);
+	}
+	drbd_suspend_io(mdev);
+	retcode = drbd_request_state(mdev, NS3(susp, 0, susp_nod, 0, susp_fen, 0));
+	if (retcode == SS_SUCCESS) {
+		if (mdev->state.conn < C_CONNECTED)
+			tl_clear(mdev->tconn);
+		if (mdev->state.disk == D_DISKLESS || mdev->state.disk == D_FAILED)
+			tl_restart(mdev->tconn, FAIL_FROZEN_DISK_IO);
+	}
+	drbd_resume_io(mdev);
+
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_outdate(struct sk_buff *skb, struct genl_info *info)
+{
+	return drbd_adm_simple_request_state(skb, info, NS(disk, D_OUTDATED));
+}
+
+int nla_put_drbd_cfg_context(struct sk_buff *skb, struct drbd_tconn *tconn, unsigned vnr)
+{
+	struct nlattr *nla;
+	nla = nla_nest_start(skb, DRBD_NLA_CFG_CONTEXT);
+	if (!nla)
+		goto nla_put_failure;
+	if (vnr != VOLUME_UNSPECIFIED &&
+	    nla_put_u32(skb, T_ctx_volume, vnr))
+		goto nla_put_failure;
+	if (nla_put_string(skb, T_ctx_resource_name, tconn->name))
+		goto nla_put_failure;
+	if (tconn->my_addr_len &&
+	    nla_put(skb, T_ctx_my_addr, tconn->my_addr_len, &tconn->my_addr))
+		goto nla_put_failure;
+	if (tconn->peer_addr_len &&
+	    nla_put(skb, T_ctx_peer_addr, tconn->peer_addr_len, &tconn->peer_addr))
+		goto nla_put_failure;
+	nla_nest_end(skb, nla);
+	return 0;
+
+nla_put_failure:
+	if (nla)
+		nla_nest_cancel(skb, nla);
+	return -EMSGSIZE;
+}
+
+int nla_put_status_info(struct sk_buff *skb, struct drbd_conf *mdev,
+		const struct sib_info *sib)
+{
+	struct state_info *si = NULL; /* for sizeof(si->member); */
+	struct net_conf *nc;
+	struct nlattr *nla;
+	int got_ldev;
+	int err = 0;
+	int exclude_sensitive;
+
+	/* If sib != NULL, this is drbd_bcast_event, which anyone can listen
+	 * to.  So we better exclude_sensitive information.
+	 *
+	 * If sib == NULL, this is drbd_adm_get_status, executed synchronously
+	 * in the context of the requesting user process. Exclude sensitive
+	 * information, unless current has superuser.
+	 *
+	 * NOTE: for drbd_adm_get_status_all(), this is a netlink dump, and
+	 * relies on the current implementation of netlink_dump(), which
+	 * executes the dump callback successively from netlink_recvmsg(),
+	 * always in the context of the receiving process */
+	exclude_sensitive = sib || !capable(CAP_SYS_ADMIN);
+
+	got_ldev = get_ldev(mdev);
+
+	/* We need to add connection name and volume number information still.
+	 * Minor number is in drbd_genlmsghdr. */
+	if (nla_put_drbd_cfg_context(skb, mdev->tconn, mdev->vnr))
+		goto nla_put_failure;
+
+	if (res_opts_to_skb(skb, &mdev->tconn->res_opts, exclude_sensitive))
+		goto nla_put_failure;
+
+	rcu_read_lock();
+	if (got_ldev)
+		if (disk_conf_to_skb(skb, rcu_dereference(mdev->ldev->disk_conf), exclude_sensitive))
+			goto nla_put_failure;
+
+	nc = rcu_dereference(mdev->tconn->net_conf);
+	if (nc)
+		err = net_conf_to_skb(skb, nc, exclude_sensitive);
+	rcu_read_unlock();
+	if (err)
+		goto nla_put_failure;
+
+	nla = nla_nest_start(skb, DRBD_NLA_STATE_INFO);
+	if (!nla)
+		goto nla_put_failure;
+	if (nla_put_u32(skb, T_sib_reason, sib ? sib->sib_reason : SIB_GET_STATUS_REPLY) ||
+	    nla_put_u32(skb, T_current_state, mdev->state.i) ||
+	    nla_put_u64(skb, T_ed_uuid, mdev->ed_uuid) ||
+	    nla_put_u64(skb, T_capacity, drbd_get_capacity(mdev->this_bdev)) ||
+	    nla_put_u64(skb, T_send_cnt, mdev->send_cnt) ||
+	    nla_put_u64(skb, T_recv_cnt, mdev->recv_cnt) ||
+	    nla_put_u64(skb, T_read_cnt, mdev->read_cnt) ||
+	    nla_put_u64(skb, T_writ_cnt, mdev->writ_cnt) ||
+	    nla_put_u64(skb, T_al_writ_cnt, mdev->al_writ_cnt) ||
+	    nla_put_u64(skb, T_bm_writ_cnt, mdev->bm_writ_cnt) ||
+	    nla_put_u32(skb, T_ap_bio_cnt, atomic_read(&mdev->ap_bio_cnt)) ||
+	    nla_put_u32(skb, T_ap_pending_cnt, atomic_read(&mdev->ap_pending_cnt)) ||
+	    nla_put_u32(skb, T_rs_pending_cnt, atomic_read(&mdev->rs_pending_cnt)))
+		goto nla_put_failure;
+
+	if (got_ldev) {
+		int err;
+
+		spin_lock_irq(&mdev->ldev->md.uuid_lock);
+		err = nla_put(skb, T_uuids, sizeof(si->uuids), mdev->ldev->md.uuid);
+		spin_unlock_irq(&mdev->ldev->md.uuid_lock);
+
+		if (err)
+			goto nla_put_failure;
+
+		if (nla_put_u32(skb, T_disk_flags, mdev->ldev->md.flags) ||
+		    nla_put_u64(skb, T_bits_total, drbd_bm_bits(mdev)) ||
+		    nla_put_u64(skb, T_bits_oos, drbd_bm_total_weight(mdev)))
+			goto nla_put_failure;
+		if (C_SYNC_SOURCE <= mdev->state.conn &&
+		    C_PAUSED_SYNC_T >= mdev->state.conn) {
+			if (nla_put_u64(skb, T_bits_rs_total, mdev->rs_total) ||
+			    nla_put_u64(skb, T_bits_rs_failed, mdev->rs_failed))
+				goto nla_put_failure;
+		}
+	}
+
+	if (sib) {
+		switch(sib->sib_reason) {
+		case SIB_SYNC_PROGRESS:
+		case SIB_GET_STATUS_REPLY:
+			break;
+		case SIB_STATE_CHANGE:
+			if (nla_put_u32(skb, T_prev_state, sib->os.i) ||
+			    nla_put_u32(skb, T_new_state, sib->ns.i))
+				goto nla_put_failure;
+			break;
+		case SIB_HELPER_POST:
+			if (nla_put_u32(skb, T_helper_exit_code,
+					sib->helper_exit_code))
+				goto nla_put_failure;
+			/* fall through */
+		case SIB_HELPER_PRE:
+			if (nla_put_string(skb, T_helper, sib->helper_name))
+				goto nla_put_failure;
+			break;
+		}
+	}
+	nla_nest_end(skb, nla);
+
+	if (0)
+nla_put_failure:
+		err = -EMSGSIZE;
+	if (got_ldev)
+		put_ldev(mdev);
+	return err;
+}
+
+int drbd_adm_get_status(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	err = nla_put_status_info(adm_ctx.reply_skb, adm_ctx.mdev, NULL);
+	if (err) {
+		nlmsg_free(adm_ctx.reply_skb);
+		return err;
+	}
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int get_one_status(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct drbd_conf *mdev;
+	struct drbd_genlmsghdr *dh;
+	struct drbd_tconn *pos = (struct drbd_tconn*)cb->args[0];
+	struct drbd_tconn *tconn = NULL;
+	struct drbd_tconn *tmp;
+	unsigned volume = cb->args[1];
+
+	/* Open coded, deferred, iteration:
+	 * list_for_each_entry_safe(tconn, tmp, &drbd_tconns, all_tconn) {
+	 *	idr_for_each_entry(&tconn->volumes, mdev, i) {
+	 *	  ...
+	 *	}
+	 * }
+	 * where tconn is cb->args[0];
+	 * and i is cb->args[1];
+	 *
+	 * cb->args[2] indicates if we shall loop over all resources,
+	 * or just dump all volumes of a single resource.
+	 *
+	 * This may miss entries inserted after this dump started,
+	 * or entries deleted before they are reached.
+	 *
+	 * We need to make sure the mdev won't disappear while
+	 * we are looking at it, and revalidate our iterators
+	 * on each iteration.
+	 */
+
+	/* synchronize with conn_create()/conn_destroy() */
+	rcu_read_lock();
+	/* revalidate iterator position */
+	list_for_each_entry_rcu(tmp, &drbd_tconns, all_tconn) {
+		if (pos == NULL) {
+			/* first iteration */
+			pos = tmp;
+			tconn = pos;
+			break;
+		}
+		if (tmp == pos) {
+			tconn = pos;
+			break;
+		}
+	}
+	if (tconn) {
+next_tconn:
+		mdev = idr_get_next(&tconn->volumes, &volume);
+		if (!mdev) {
+			/* No more volumes to dump on this tconn.
+			 * Advance tconn iterator. */
+			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,
+				 * or only a single resource dump was requested,
+				 * we are done. */
+				if (&pos->all_tconn == &drbd_tconns || cb->args[2])
+					goto out;
+				volume = 0;
+				tconn = pos;
+				goto next_tconn;
+			}
+		}
+
+		dh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
+				cb->nlh->nlmsg_seq, &drbd_genl_family,
+				NLM_F_MULTI, DRBD_ADM_GET_STATUS);
+		if (!dh)
+			goto out;
+
+		if (!mdev) {
+			/* This is a tconn without a single volume.
+			 * Suprisingly enough, it may have a network
+			 * configuration. */
+			struct net_conf *nc;
+			dh->minor = -1U;
+			dh->ret_code = NO_ERROR;
+			if (nla_put_drbd_cfg_context(skb, tconn, VOLUME_UNSPECIFIED))
+				goto cancel;
+			nc = rcu_dereference(tconn->net_conf);
+			if (nc && net_conf_to_skb(skb, nc, 1) != 0)
+				goto cancel;
+			goto done;
+		}
+
+		D_ASSERT(mdev->vnr == volume);
+		D_ASSERT(mdev->tconn == tconn);
+
+		dh->minor = mdev_to_minor(mdev);
+		dh->ret_code = NO_ERROR;
+
+		if (nla_put_status_info(skb, mdev, NULL)) {
+cancel:
+			genlmsg_cancel(skb, dh);
+			goto out;
+		}
+done:
+		genlmsg_end(skb, dh);
+        }
+
+out:
+	rcu_read_unlock();
+	/* where to start the next iteration */
+        cb->args[0] = (long)pos;
+        cb->args[1] = (pos == tconn) ? volume + 1 : 0;
+
+	/* No more tconns/volumes/minors found results in an empty skb.
+	 * Which will terminate the dump. */
+        return skb->len;
+}
+
+/*
+ * Request status of all resources, or of all volumes within a single resource.
+ *
+ * This is a dump, as the answer may not fit in a single reply skb otherwise.
+ * Which means we cannot use the family->attrbuf or other such members, because
+ * dump is NOT protected by the genl_lock().  During dump, we only have access
+ * to the incoming skb, and need to opencode "parsing" of the nlattr payload.
+ *
+ * Once things are setup properly, we call into get_one_status().
+ */
+int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	const unsigned hdrlen = GENL_HDRLEN + GENL_MAGIC_FAMILY_HDRSZ;
+	struct nlattr *nla;
+	const char *resource_name;
+	struct drbd_tconn *tconn;
+	int maxtype;
+
+	/* Is this a followup call? */
+	if (cb->args[0]) {
+		/* ... of a single resource dump,
+		 * and the resource iterator has been advanced already? */
+		if (cb->args[2] && cb->args[2] != cb->args[0])
+			return 0; /* DONE. */
+		goto dump;
+	}
+
+	/* First call (from netlink_dump_start).  We need to figure out
+	 * which resource(s) the user wants us to dump. */
+	nla = nla_find(nlmsg_attrdata(cb->nlh, hdrlen),
+			nlmsg_attrlen(cb->nlh, hdrlen),
+			DRBD_NLA_CFG_CONTEXT);
+
+	/* No explicit context given.  Dump all. */
+	if (!nla)
+		goto dump;
+	maxtype = ARRAY_SIZE(drbd_cfg_context_nl_policy) - 1;
+	nla = drbd_nla_find_nested(maxtype, nla, __nla_type(T_ctx_resource_name));
+	if (IS_ERR(nla))
+		return PTR_ERR(nla);
+	/* context given, but no name present? */
+	if (!nla)
+		return -EINVAL;
+	resource_name = nla_data(nla);
+	tconn = conn_get_by_name(resource_name);
+
+	if (!tconn)
+		return -ENODEV;
+
+	kref_put(&tconn->kref, &conn_destroy); /* get_one_status() (re)validates tconn by itself */
+
+	/* prime iterators, and set "filter" mode mark:
+	 * only dump this tconn. */
+	cb->args[0] = (long)tconn;
+	/* cb->args[1] = 0; passed in this way. */
+	cb->args[2] = (long)tconn;
+
+dump:
+	return get_one_status(skb, cb);
+}
+
+int drbd_adm_get_timeout_type(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+	struct timeout_parms tp;
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	tp.timeout_type =
+		adm_ctx.mdev->state.pdsk == D_OUTDATED ? UT_PEER_OUTDATED :
+		test_bit(USE_DEGR_WFC_T, &adm_ctx.mdev->flags) ? UT_DEGRADED :
+		UT_DEFAULT;
+
+	err = timeout_parms_to_priv_skb(adm_ctx.reply_skb, &tp);
+	if (err) {
+		nlmsg_free(adm_ctx.reply_skb);
+		return err;
+	}
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_start_ov(struct sk_buff *skb, struct genl_info *info)
+{
+	struct drbd_conf *mdev;
+	enum drbd_ret_code retcode;
+	struct start_ov_parms parms;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	mdev = adm_ctx.mdev;
+
+	/* resume from last known position, if possible */
+	parms.ov_start_sector = mdev->ov_start_sector;
+	parms.ov_stop_sector = ULLONG_MAX;
+	if (info->attrs[DRBD_NLA_START_OV_PARMS]) {
+		int err = start_ov_parms_from_attrs(&parms, info);
+		if (err) {
+			retcode = ERR_MANDATORY_TAG;
+			drbd_msg_put_info(from_attrs_err_to_txt(err));
+			goto out;
+		}
+	}
+	/* w_make_ov_request expects position to be aligned */
+	mdev->ov_start_sector = parms.ov_start_sector & ~(BM_SECT_PER_BIT-1);
+	mdev->ov_stop_sector = parms.ov_stop_sector;
+
+	/* If there is still bitmap IO pending, e.g. previous resync or verify
+	 * just being finished, wait for it before requesting a new resync. */
+	drbd_suspend_io(mdev);
+	wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
+	retcode = drbd_request_state(mdev,NS(conn,C_VERIFY_S));
+	drbd_resume_io(mdev);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+
+int drbd_adm_new_c_uuid(struct sk_buff *skb, struct genl_info *info)
+{
+	struct drbd_conf *mdev;
+	enum drbd_ret_code retcode;
+	int skip_initial_sync = 0;
+	int err;
+	struct new_c_uuid_parms args;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out_nolock;
+
+	mdev = adm_ctx.mdev;
+	memset(&args, 0, sizeof(args));
+	if (info->attrs[DRBD_NLA_NEW_C_UUID_PARMS]) {
+		err = new_c_uuid_parms_from_attrs(&args, info);
+		if (err) {
+			retcode = ERR_MANDATORY_TAG;
+			drbd_msg_put_info(from_attrs_err_to_txt(err));
+			goto out_nolock;
+		}
+	}
+
+	mutex_lock(mdev->state_mutex); /* Protects us against serialized state changes. */
+
+	if (!get_ldev(mdev)) {
+		retcode = ERR_NO_DISK;
+		goto out;
+	}
+
+	/* this is "skip initial sync", assume to be clean */
+	if (mdev->state.conn == C_CONNECTED && mdev->tconn->agreed_pro_version >= 90 &&
+	    mdev->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED && args.clear_bm) {
+		dev_info(DEV, "Preparing to skip initial sync\n");
+		skip_initial_sync = 1;
+	} else if (mdev->state.conn != C_STANDALONE) {
+		retcode = ERR_CONNECTED;
+		goto out_dec;
+	}
+
+	drbd_uuid_set(mdev, UI_BITMAP, 0); /* Rotate UI_BITMAP to History 1, etc... */
+	drbd_uuid_new_current(mdev); /* New current, previous to UI_BITMAP */
+
+	if (args.clear_bm) {
+		err = drbd_bitmap_io(mdev, &drbd_bmio_clear_n_write,
+			"clear_n_write from new_c_uuid", BM_LOCKED_MASK);
+		if (err) {
+			dev_err(DEV, "Writing bitmap failed with %d\n",err);
+			retcode = ERR_IO_MD_DISK;
+		}
+		if (skip_initial_sync) {
+			drbd_send_uuids_skip_initial_sync(mdev);
+			_drbd_uuid_set(mdev, UI_BITMAP, 0);
+			drbd_print_uuids(mdev, "cleared bitmap UUID");
+			spin_lock_irq(&mdev->tconn->req_lock);
+			_drbd_set_state(_NS2(mdev, disk, D_UP_TO_DATE, pdsk, D_UP_TO_DATE),
+					CS_VERBOSE, NULL);
+			spin_unlock_irq(&mdev->tconn->req_lock);
+		}
+	}
+
+	drbd_md_sync(mdev);
+out_dec:
+	put_ldev(mdev);
+out:
+	mutex_unlock(mdev->state_mutex);
+out_nolock:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+static enum drbd_ret_code
+drbd_check_resource_name(const char *name)
+{
+	if (!name || !name[0]) {
+		drbd_msg_put_info("resource name missing");
+		return ERR_MANDATORY_TAG;
+	}
+	/* if we want to use these in sysfs/configfs/debugfs some day,
+	 * we must not allow slashes */
+	if (strchr(name, '/')) {
+		drbd_msg_put_info("invalid resource name");
+		return ERR_INVALID_REQUEST;
+	}
+	return NO_ERROR;
+}
+
+int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+	struct res_opts res_opts;
+	int err;
+
+	retcode = drbd_adm_prepare(skb, info, 0);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	set_res_opts_defaults(&res_opts);
+	err = res_opts_from_attrs(&res_opts, info);
+	if (err && err != -ENOMSG) {
+		retcode = ERR_MANDATORY_TAG;
+		drbd_msg_put_info(from_attrs_err_to_txt(err));
+		goto out;
+	}
+
+	retcode = drbd_check_resource_name(adm_ctx.resource_name);
+	if (retcode != NO_ERROR)
+		goto out;
+
+	if (adm_ctx.tconn) {
+		if (info->nlhdr->nlmsg_flags & NLM_F_EXCL) {
+			retcode = ERR_INVALID_REQUEST;
+			drbd_msg_put_info("resource exists");
+		}
+		/* else: still NO_ERROR */
+		goto out;
+	}
+
+	if (!conn_create(adm_ctx.resource_name, &res_opts))
+		retcode = ERR_NOMEM;
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_add_minor(struct sk_buff *skb, struct genl_info *info)
+{
+	struct drbd_genlmsghdr *dh = info->userhdr;
+	enum drbd_ret_code retcode;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_RESOURCE);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	if (dh->minor > MINORMASK) {
+		drbd_msg_put_info("requested minor out of range");
+		retcode = ERR_INVALID_REQUEST;
+		goto out;
+	}
+	if (adm_ctx.volume > DRBD_VOLUME_MAX) {
+		drbd_msg_put_info("requested volume id out of range");
+		retcode = ERR_INVALID_REQUEST;
+		goto out;
+	}
+
+	/* drbd_adm_prepare made sure already
+	 * that mdev->tconn and mdev->vnr match the request. */
+	if (adm_ctx.mdev) {
+		if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
+			retcode = ERR_MINOR_EXISTS;
+		/* else: still NO_ERROR */
+		goto out;
+	}
+
+	retcode = conn_new_minor(adm_ctx.tconn, dh->minor, adm_ctx.volume);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+static enum drbd_ret_code adm_delete_minor(struct drbd_conf *mdev)
+{
+	if (mdev->state.disk == D_DISKLESS &&
+	    /* no need to be mdev->state.conn == C_STANDALONE &&
+	     * we may want to delete a minor from a live replication group.
+	     */
+	    mdev->state.role == R_SECONDARY) {
+		_drbd_request_state(mdev, NS(conn, C_WF_REPORT_PARAMS),
+				    CS_VERBOSE + CS_WAIT_COMPLETE);
+		idr_remove(&mdev->tconn->volumes, mdev->vnr);
+		idr_remove(&minors, mdev_to_minor(mdev));
+		destroy_workqueue(mdev->submit.wq);
+		del_gendisk(mdev->vdisk);
+		synchronize_rcu();
+		kref_put(&mdev->kref, &drbd_minor_destroy);
+		return NO_ERROR;
+	} else
+		return ERR_MINOR_CONFIGURED;
+}
+
+int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	retcode = adm_delete_minor(adm_ctx.mdev);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
+{
+	int retcode; /* enum drbd_ret_code rsp. enum drbd_state_rv */
+	struct drbd_conf *mdev;
+	unsigned i;
+
+	retcode = drbd_adm_prepare(skb, info, 0);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	if (!adm_ctx.tconn) {
+		retcode = ERR_RES_NOT_KNOWN;
+		goto out;
+	}
+
+	/* 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;
+		}
+	}
+
+	retcode = conn_try_disconnect(adm_ctx.tconn, 0);
+	if (retcode < SS_SUCCESS) {
+		drbd_msg_put_info("failed to disconnect");
+		goto out;
+	}
+
+	/* detach */
+	idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {
+		retcode = adm_detach(mdev, 0);
+		if (retcode < SS_SUCCESS || retcode > NO_ERROR) {
+			drbd_msg_put_info("failed to detach");
+			goto out;
+		}
+	}
+
+	/* 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(). */
+	drbd_thread_stop(&adm_ctx.tconn->worker);
+
+	/* Now, nothing can fail anymore */
+
+	/* delete volumes */
+	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");
+			goto out;
+		}
+	}
+
+	/* delete connection */
+	if (conn_lowest_minor(adm_ctx.tconn) < 0) {
+		list_del_rcu(&adm_ctx.tconn->all_tconn);
+		synchronize_rcu();
+		kref_put(&adm_ctx.tconn->kref, &conn_destroy);
+
+		retcode = NO_ERROR;
+	} else {
+		/* "can not happen" */
+		retcode = ERR_RES_IN_USE;
+		drbd_msg_put_info("failed to delete connection");
+	}
+	goto out;
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+int drbd_adm_del_resource(struct sk_buff *skb, struct genl_info *info)
+{
+	enum drbd_ret_code retcode;
+
+	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_RESOURCE);
+	if (!adm_ctx.reply_skb)
+		return retcode;
+	if (retcode != NO_ERROR)
+		goto out;
+
+	if (conn_lowest_minor(adm_ctx.tconn) < 0) {
+		list_del_rcu(&adm_ctx.tconn->all_tconn);
+		synchronize_rcu();
+		kref_put(&adm_ctx.tconn->kref, &conn_destroy);
+
+		retcode = NO_ERROR;
+	} else {
+		retcode = ERR_RES_IN_USE;
+	}
+
+	if (retcode == NO_ERROR)
+		drbd_thread_stop(&adm_ctx.tconn->worker);
+out:
+	drbd_adm_finish(info, retcode);
+	return 0;
+}
+
+void drbd_bcast_event(struct drbd_conf *mdev, const struct sib_info *sib)
+{
+	static atomic_t drbd_genl_seq = ATOMIC_INIT(2); /* two. */
+	struct sk_buff *msg;
+	struct drbd_genlmsghdr *d_out;
+	unsigned seq;
+	int err = -ENOMEM;
+
+	if (sib->sib_reason == SIB_SYNC_PROGRESS) {
+		if (time_after(jiffies, mdev->rs_last_bcast + HZ))
+			mdev->rs_last_bcast = jiffies;
+		else
+			return;
+	}
+
+	seq = atomic_inc_return(&drbd_genl_seq);
+	msg = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO);
+	if (!msg)
+		goto failed;
+
+	err = -EMSGSIZE;
+	d_out = genlmsg_put(msg, 0, seq, &drbd_genl_family, 0, DRBD_EVENT);
+	if (!d_out) /* cannot happen, but anyways. */
+		goto nla_put_failure;
+	d_out->minor = mdev_to_minor(mdev);
+	d_out->ret_code = NO_ERROR;
+
+	if (nla_put_status_info(msg, mdev, sib))
+		goto nla_put_failure;
+	genlmsg_end(msg, d_out);
+	err = drbd_genl_multicast_events(msg, 0);
+	/* msg has been consumed or freed in netlink_broadcast() */
+	if (err && err != -ESRCH)
+		goto failed;
+
+	return;
+
+nla_put_failure:
+	nlmsg_free(msg);
+failed:
+	dev_err(DEV, "Error %d while broadcasting event. "
+			"Event seq:%u sib_reason:%u\n",
+			err, seq, sib->sib_reason);
+}