drivers/block/drbd/drbd_nl.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3    drbd_nl.c
   4
   5    This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
   6
   7    Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
   8    Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
   9    Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
  10
  11
  12  */
  13
  14 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/module.h>
  17 #include <linux/drbd.h>
  18 #include <linux/in.h>
  19 #include <linux/fs.h>
  20 #include <linux/file.h>
  21 #include <linux/slab.h>
  22 #include <linux/blkpg.h>
  23 #include <linux/cpumask.h>
  24 #include "drbd_int.h"
  25 #include "drbd_protocol.h"
  26 #include "drbd_req.h"
  27 #include "drbd_state_change.h"
  28 #include <asm/unaligned.h>
  29 #include <linux/drbd_limits.h>
  30 #include <linux/kthread.h>
  31
  32 #include <net/genetlink.h>
  33
  34 /* .doit */
  35 // int drbd_adm_create_resource(struct sk_buff *skb, struct genl_info *info);
  36 // int drbd_adm_delete_resource(struct sk_buff *skb, struct genl_info *info);
  37
  38 int drbd_adm_new_minor(struct sk_buff *skb, struct genl_info *info);
  39 int drbd_adm_del_minor(struct sk_buff *skb, struct genl_info *info);
  40
  41 int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info);
  42 int drbd_adm_del_resource(struct sk_buff *skb, struct genl_info *info);
  43 int drbd_adm_down(struct sk_buff *skb, struct genl_info *info);
  44
  45 int drbd_adm_set_role(struct sk_buff *skb, struct genl_info *info);
  46 int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info);
  47 int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info);
  48 int drbd_adm_detach(struct sk_buff *skb, struct genl_info *info);
  49 int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info);
  50 int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info);
  51 int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info);
  52 int drbd_adm_start_ov(struct sk_buff *skb, struct genl_info *info);
  53 int drbd_adm_new_c_uuid(struct sk_buff *skb, struct genl_info *info);
  54 int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info);
  55 int drbd_adm_invalidate(struct sk_buff *skb, struct genl_info *info);
  56 int drbd_adm_invalidate_peer(struct sk_buff *skb, struct genl_info *info);
  57 int drbd_adm_pause_sync(struct sk_buff *skb, struct genl_info *info);
  58 int drbd_adm_resume_sync(struct sk_buff *skb, struct genl_info *info);
  59 int drbd_adm_suspend_io(struct sk_buff *skb, struct genl_info *info);
  60 int drbd_adm_resume_io(struct sk_buff *skb, struct genl_info *info);
  61 int drbd_adm_outdate(struct sk_buff *skb, struct genl_info *info);
  62 int drbd_adm_resource_opts(struct sk_buff *skb, struct genl_info *info);
  63 int drbd_adm_get_status(struct sk_buff *skb, struct genl_info *info);
  64 int drbd_adm_get_timeout_type(struct sk_buff *skb, struct genl_info *info);
  65 /* .dumpit */
  66 int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb);
  67 int drbd_adm_dump_resources(struct sk_buff *skb, struct netlink_callback *cb);
  68 int drbd_adm_dump_devices(struct sk_buff *skb, struct netlink_callback *cb);
  69 int drbd_adm_dump_devices_done(struct netlink_callback *cb);
  70 int drbd_adm_dump_connections(struct sk_buff *skb, struct netlink_callback *cb);
  71 int drbd_adm_dump_connections_done(struct netlink_callback *cb);
  72 int drbd_adm_dump_peer_devices(struct sk_buff *skb, struct netlink_callback *cb);
  73 int drbd_adm_dump_peer_devices_done(struct netlink_callback *cb);
  74 int drbd_adm_get_initial_state(struct sk_buff *skb, struct netlink_callback *cb);
  75
  76 #include <linux/drbd_genl_api.h>
  77 #include "drbd_nla.h"
  78 #include <linux/genl_magic_func.h>
  79
  80 static atomic_t drbd_genl_seq = ATOMIC_INIT(2); /* two. */
  81 static atomic_t notify_genl_seq = ATOMIC_INIT(2); /* two. */
  82
  83 DEFINE_MUTEX(notification_mutex);
  84
  85 /* used blkdev_get_by_path, to claim our meta data device(s) */
  86 static char *drbd_m_holder = "Hands off! this is DRBD's meta data device.";
  87
  88 static void drbd_adm_send_reply(struct sk_buff *skb, struct genl_info *info)
  89 {
  90         genlmsg_end(skb, genlmsg_data(nlmsg_data(nlmsg_hdr(skb))));
  91         if (genlmsg_reply(skb, info))
  92                 pr_err("error sending genl reply\n");
  93 }
  94
  95 /* Used on a fresh "drbd_adm_prepare"d reply_skb, this cannot fail: The only
  96  * reason it could fail was no space in skb, and there are 4k available. */
  97 static int drbd_msg_put_info(struct sk_buff *skb, const char *info)
  98 {
  99         struct nlattr *nla;
 100         int err = -EMSGSIZE;
 101
 102         if (!info || !info[0])
 103                 return 0;
 104
 105         nla = nla_nest_start_noflag(skb, DRBD_NLA_CFG_REPLY);
 106         if (!nla)
 107                 return err;
 108
 109         err = nla_put_string(skb, T_info_text, info);
 110         if (err) {
 111                 nla_nest_cancel(skb, nla);
 112                 return err;
 113         } else
 114                 nla_nest_end(skb, nla);
 115         return 0;
 116 }
 117
 118 __printf(2, 3)
 119 static int drbd_msg_sprintf_info(struct sk_buff *skb, const char *fmt, ...)
 120 {
 121         va_list args;
 122         struct nlattr *nla, *txt;
 123         int err = -EMSGSIZE;
 124         int len;
 125
 126         nla = nla_nest_start_noflag(skb, DRBD_NLA_CFG_REPLY);
 127         if (!nla)
 128                 return err;
 129
 130         txt = nla_reserve(skb, T_info_text, 256);
 131         if (!txt) {
 132                 nla_nest_cancel(skb, nla);
 133                 return err;
 134         }
 135         va_start(args, fmt);
 136         len = vscnprintf(nla_data(txt), 256, fmt, args);
 137         va_end(args);
 138
 139         /* maybe: retry with larger reserve, if truncated */
 140         txt->nla_len = nla_attr_size(len+1);
 141         nlmsg_trim(skb, (char*)txt + NLA_ALIGN(txt->nla_len));
 142         nla_nest_end(skb, nla);
 143
 144         return 0;
 145 }
 146
 147 /* This would be a good candidate for a "pre_doit" hook,
 148  * and per-family private info->pointers.
 149  * But we need to stay compatible with older kernels.
 150  * If it returns successfully, adm_ctx members are valid.
 151  *
 152  * At this point, we still rely on the global genl_lock().
 153  * If we want to avoid that, and allow "genl_family.parallel_ops", we may need
 154  * to add additional synchronization against object destruction/modification.
 155  */
 156 #define DRBD_ADM_NEED_MINOR     1
 157 #define DRBD_ADM_NEED_RESOURCE  2
 158 #define DRBD_ADM_NEED_CONNECTION 4
 159 static int drbd_adm_prepare(struct drbd_config_context *adm_ctx,
 160         struct sk_buff *skb, struct genl_info *info, unsigned flags)
 161 {
 162         struct drbd_genlmsghdr *d_in = genl_info_userhdr(info);
 163         const u8 cmd = info->genlhdr->cmd;
 164         int err;
 165
 166         memset(adm_ctx, 0, sizeof(*adm_ctx));
 167
 168         /* genl_rcv_msg only checks for CAP_NET_ADMIN on "GENL_ADMIN_PERM" :( */
 169         if (cmd != DRBD_ADM_GET_STATUS && !capable(CAP_NET_ADMIN))
 170                return -EPERM;
 171
 172         adm_ctx->reply_skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 173         if (!adm_ctx->reply_skb) {
 174                 err = -ENOMEM;
 175                 goto fail;
 176         }
 177
 178         adm_ctx->reply_dh = genlmsg_put_reply(adm_ctx->reply_skb,
 179                                         info, &drbd_genl_family, 0, cmd);
 180         /* put of a few bytes into a fresh skb of >= 4k will always succeed.
 181          * but anyways */
 182         if (!adm_ctx->reply_dh) {
 183                 err = -ENOMEM;
 184                 goto fail;
 185         }
 186
 187         adm_ctx->reply_dh->minor = d_in->minor;
 188         adm_ctx->reply_dh->ret_code = NO_ERROR;
 189
 190         adm_ctx->volume = VOLUME_UNSPECIFIED;
 191         if (info->attrs[DRBD_NLA_CFG_CONTEXT]) {
 192                 struct nlattr *nla;
 193                 /* parse and validate only */
 194                 err = drbd_cfg_context_from_attrs(NULL, info);
 195                 if (err)
 196                         goto fail;
 197
 198                 /* It was present, and valid,
 199                  * copy it over to the reply skb. */
 200                 err = nla_put_nohdr(adm_ctx->reply_skb,
 201                                 info->attrs[DRBD_NLA_CFG_CONTEXT]->nla_len,
 202                                 info->attrs[DRBD_NLA_CFG_CONTEXT]);
 203                 if (err)
 204                         goto fail;
 205
 206                 /* and assign stuff to the adm_ctx */
 207                 nla = nested_attr_tb[__nla_type(T_ctx_volume)];
 208                 if (nla)
 209                         adm_ctx->volume = nla_get_u32(nla);
 210                 nla = nested_attr_tb[__nla_type(T_ctx_resource_name)];
 211                 if (nla)
 212                         adm_ctx->resource_name = nla_data(nla);
 213                 adm_ctx->my_addr = nested_attr_tb[__nla_type(T_ctx_my_addr)];
 214                 adm_ctx->peer_addr = nested_attr_tb[__nla_type(T_ctx_peer_addr)];
 215                 if ((adm_ctx->my_addr &&
 216                      nla_len(adm_ctx->my_addr) > sizeof(adm_ctx->connection->my_addr)) ||
 217                     (adm_ctx->peer_addr &&
 218                      nla_len(adm_ctx->peer_addr) > sizeof(adm_ctx->connection->peer_addr))) {
 219                         err = -EINVAL;
 220                         goto fail;
 221                 }
 222         }
 223
 224         adm_ctx->minor = d_in->minor;
 225         adm_ctx->device = minor_to_device(d_in->minor);
 226
 227         /* We are protected by the global genl_lock().
 228          * But we may explicitly drop it/retake it in drbd_adm_set_role(),
 229          * so make sure this object stays around. */
 230         if (adm_ctx->device)
 231                 kref_get(&adm_ctx->device->kref);
 232
 233         if (adm_ctx->resource_name) {
 234                 adm_ctx->resource = drbd_find_resource(adm_ctx->resource_name);
 235         }
 236
 237         if (!adm_ctx->device && (flags & DRBD_ADM_NEED_MINOR)) {
 238                 drbd_msg_put_info(adm_ctx->reply_skb, "unknown minor");
 239                 return ERR_MINOR_INVALID;
 240         }
 241         if (!adm_ctx->resource && (flags & DRBD_ADM_NEED_RESOURCE)) {
 242                 drbd_msg_put_info(adm_ctx->reply_skb, "unknown resource");
 243                 if (adm_ctx->resource_name)
 244                         return ERR_RES_NOT_KNOWN;
 245                 return ERR_INVALID_REQUEST;
 246         }
 247
 248         if (flags & DRBD_ADM_NEED_CONNECTION) {
 249                 if (adm_ctx->resource) {
 250                         drbd_msg_put_info(adm_ctx->reply_skb, "no resource name expected");
 251                         return ERR_INVALID_REQUEST;
 252                 }
 253                 if (adm_ctx->device) {
 254                         drbd_msg_put_info(adm_ctx->reply_skb, "no minor number expected");
 255                         return ERR_INVALID_REQUEST;
 256                 }
 257                 if (adm_ctx->my_addr && adm_ctx->peer_addr)
 258                         adm_ctx->connection = conn_get_by_addrs(nla_data(adm_ctx->my_addr),
 259                                                           nla_len(adm_ctx->my_addr),
 260                                                           nla_data(adm_ctx->peer_addr),
 261                                                           nla_len(adm_ctx->peer_addr));
 262                 if (!adm_ctx->connection) {
 263                         drbd_msg_put_info(adm_ctx->reply_skb, "unknown connection");
 264                         return ERR_INVALID_REQUEST;
 265                 }
 266         }
 267
 268         /* some more paranoia, if the request was over-determined */
 269         if (adm_ctx->device && adm_ctx->resource &&
 270             adm_ctx->device->resource != adm_ctx->resource) {
 271                 pr_warn("request: minor=%u, resource=%s; but that minor belongs to resource %s\n",
 272                         adm_ctx->minor, adm_ctx->resource->name,
 273                         adm_ctx->device->resource->name);
 274                 drbd_msg_put_info(adm_ctx->reply_skb, "minor exists in different resource");
 275                 return ERR_INVALID_REQUEST;
 276         }
 277         if (adm_ctx->device &&
 278             adm_ctx->volume != VOLUME_UNSPECIFIED &&
 279             adm_ctx->volume != adm_ctx->device->vnr) {
 280                 pr_warn("request: minor=%u, volume=%u; but that minor is volume %u in %s\n",
 281                         adm_ctx->minor, adm_ctx->volume,
 282                         adm_ctx->device->vnr, adm_ctx->device->resource->name);
 283                 drbd_msg_put_info(adm_ctx->reply_skb, "minor exists as different volume");
 284                 return ERR_INVALID_REQUEST;
 285         }
 286
 287         /* still, provide adm_ctx->resource always, if possible. */
 288         if (!adm_ctx->resource) {
 289                 adm_ctx->resource = adm_ctx->device ? adm_ctx->device->resource
 290                         : adm_ctx->connection ? adm_ctx->connection->resource : NULL;
 291                 if (adm_ctx->resource)
 292                         kref_get(&adm_ctx->resource->kref);
 293         }
 294
 295         return NO_ERROR;
 296
 297 fail:
 298         nlmsg_free(adm_ctx->reply_skb);
 299         adm_ctx->reply_skb = NULL;
 300         return err;
 301 }
 302
 303 static int drbd_adm_finish(struct drbd_config_context *adm_ctx,
 304         struct genl_info *info, int retcode)
 305 {
 306         if (adm_ctx->device) {
 307                 kref_put(&adm_ctx->device->kref, drbd_destroy_device);
 308                 adm_ctx->device = NULL;
 309         }
 310         if (adm_ctx->connection) {
 311                 kref_put(&adm_ctx->connection->kref, &drbd_destroy_connection);
 312                 adm_ctx->connection = NULL;
 313         }
 314         if (adm_ctx->resource) {
 315                 kref_put(&adm_ctx->resource->kref, drbd_destroy_resource);
 316                 adm_ctx->resource = NULL;
 317         }
 318
 319         if (!adm_ctx->reply_skb)
 320                 return -ENOMEM;
 321
 322         adm_ctx->reply_dh->ret_code = retcode;
 323         drbd_adm_send_reply(adm_ctx->reply_skb, info);
 324         return 0;
 325 }
 326
 327 static void setup_khelper_env(struct drbd_connection *connection, char **envp)
 328 {
 329         char *afs;
 330
 331         /* FIXME: A future version will not allow this case. */
 332         if (connection->my_addr_len == 0 || connection->peer_addr_len == 0)
 333                 return;
 334
 335         switch (((struct sockaddr *)&connection->peer_addr)->sa_family) {
 336         case AF_INET6:
 337                 afs = "ipv6";
 338                 snprintf(envp[4], 60, "DRBD_PEER_ADDRESS=%pI6",
 339                          &((struct sockaddr_in6 *)&connection->peer_addr)->sin6_addr);
 340                 break;
 341         case AF_INET:
 342                 afs = "ipv4";
 343                 snprintf(envp[4], 60, "DRBD_PEER_ADDRESS=%pI4",
 344                          &((struct sockaddr_in *)&connection->peer_addr)->sin_addr);
 345                 break;
 346         default:
 347                 afs = "ssocks";
 348                 snprintf(envp[4], 60, "DRBD_PEER_ADDRESS=%pI4",
 349                          &((struct sockaddr_in *)&connection->peer_addr)->sin_addr);
 350         }
 351         snprintf(envp[3], 20, "DRBD_PEER_AF=%s", afs);
 352 }
 353
 354 int drbd_khelper(struct drbd_device *device, char *cmd)
 355 {
 356         char *envp[] = { "HOME=/",
 357                         "TERM=linux",
 358                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
 359                          (char[20]) { }, /* address family */
 360                          (char[60]) { }, /* address */
 361                         NULL };
 362         char mb[14];
 363         char *argv[] = {drbd_usermode_helper, cmd, mb, NULL };
 364         struct drbd_connection *connection = first_peer_device(device)->connection;
 365         struct sib_info sib;
 366         int ret;
 367
 368         if (current == connection->worker.task)
 369                 set_bit(CALLBACK_PENDING, &connection->flags);
 370
 371         snprintf(mb, 14, "minor-%d", device_to_minor(device));
 372         setup_khelper_env(connection, envp);
 373
 374         /* The helper may take some time.
 375          * write out any unsynced meta data changes now */
 376         drbd_md_sync(device);
 377
 378         drbd_info(device, "helper command: %s %s %s\n", drbd_usermode_helper, cmd, mb);
 379         sib.sib_reason = SIB_HELPER_PRE;
 380         sib.helper_name = cmd;
 381         drbd_bcast_event(device, &sib);
 382         notify_helper(NOTIFY_CALL, device, connection, cmd, 0);
 383         ret = call_usermodehelper(drbd_usermode_helper, argv, envp, UMH_WAIT_PROC);
 384         if (ret)
 385                 drbd_warn(device, "helper command: %s %s %s exit code %u (0x%x)\n",
 386                                 drbd_usermode_helper, cmd, mb,
 387                                 (ret >> 8) & 0xff, ret);
 388         else
 389                 drbd_info(device, "helper command: %s %s %s exit code %u (0x%x)\n",
 390                                 drbd_usermode_helper, cmd, mb,
 391                                 (ret >> 8) & 0xff, ret);
 392         sib.sib_reason = SIB_HELPER_POST;
 393         sib.helper_exit_code = ret;
 394         drbd_bcast_event(device, &sib);
 395         notify_helper(NOTIFY_RESPONSE, device, connection, cmd, ret);
 396
 397         if (current == connection->worker.task)
 398                 clear_bit(CALLBACK_PENDING, &connection->flags);
 399
 400         if (ret < 0) /* Ignore any ERRNOs we got. */
 401                 ret = 0;
 402
 403         return ret;
 404 }
 405
 406 enum drbd_peer_state conn_khelper(struct drbd_connection *connection, char *cmd)
 407 {
 408         char *envp[] = { "HOME=/",
 409                         "TERM=linux",
 410                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
 411                          (char[20]) { }, /* address family */
 412                          (char[60]) { }, /* address */
 413                         NULL };
 414         char *resource_name = connection->resource->name;
 415         char *argv[] = {drbd_usermode_helper, cmd, resource_name, NULL };
 416         int ret;
 417
 418         setup_khelper_env(connection, envp);
 419         conn_md_sync(connection);
 420
 421         drbd_info(connection, "helper command: %s %s %s\n", drbd_usermode_helper, cmd, resource_name);
 422         /* TODO: conn_bcast_event() ?? */
 423         notify_helper(NOTIFY_CALL, NULL, connection, cmd, 0);
 424
 425         ret = call_usermodehelper(drbd_usermode_helper, argv, envp, UMH_WAIT_PROC);
 426         if (ret)
 427                 drbd_warn(connection, "helper command: %s %s %s exit code %u (0x%x)\n",
 428                           drbd_usermode_helper, cmd, resource_name,
 429                           (ret >> 8) & 0xff, ret);
 430         else
 431                 drbd_info(connection, "helper command: %s %s %s exit code %u (0x%x)\n",
 432                           drbd_usermode_helper, cmd, resource_name,
 433                           (ret >> 8) & 0xff, ret);
 434         /* TODO: conn_bcast_event() ?? */
 435         notify_helper(NOTIFY_RESPONSE, NULL, connection, cmd, ret);
 436
 437         if (ret < 0) /* Ignore any ERRNOs we got. */
 438                 ret = 0;
 439
 440         return ret;
 441 }
 442
 443 static enum drbd_fencing_p highest_fencing_policy(struct drbd_connection *connection)
 444 {
 445         enum drbd_fencing_p fp = FP_NOT_AVAIL;
 446         struct drbd_peer_device *peer_device;
 447         int vnr;
 448
 449         rcu_read_lock();
 450         idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
 451                 struct drbd_device *device = peer_device->device;
 452                 if (get_ldev_if_state(device, D_CONSISTENT)) {
 453                         struct disk_conf *disk_conf =
 454                                 rcu_dereference(peer_device->device->ldev->disk_conf);
 455                         fp = max_t(enum drbd_fencing_p, fp, disk_conf->fencing);
 456                         put_ldev(device);
 457                 }
 458         }
 459         rcu_read_unlock();
 460
 461         return fp;
 462 }
 463
 464 static bool resource_is_supended(struct drbd_resource *resource)
 465 {
 466         return resource->susp || resource->susp_fen || resource->susp_nod;
 467 }
 468
 469 bool conn_try_outdate_peer(struct drbd_connection *connection)
 470 {
 471         struct drbd_resource * const resource = connection->resource;
 472         unsigned int connect_cnt;
 473         union drbd_state mask = { };
 474         union drbd_state val = { };
 475         enum drbd_fencing_p fp;
 476         char *ex_to_string;
 477         int r;
 478
 479         spin_lock_irq(&resource->req_lock);
 480         if (connection->cstate >= C_WF_REPORT_PARAMS) {
 481                 drbd_err(connection, "Expected cstate < C_WF_REPORT_PARAMS\n");
 482                 spin_unlock_irq(&resource->req_lock);
 483                 return false;
 484         }
 485
 486         connect_cnt = connection->connect_cnt;
 487         spin_unlock_irq(&resource->req_lock);
 488
 489         fp = highest_fencing_policy(connection);
 490         switch (fp) {
 491         case FP_NOT_AVAIL:
 492                 drbd_warn(connection, "Not fencing peer, I'm not even Consistent myself.\n");
 493                 spin_lock_irq(&resource->req_lock);
 494                 if (connection->cstate < C_WF_REPORT_PARAMS) {
 495                         _conn_request_state(connection,
 496                                             (union drbd_state) { { .susp_fen = 1 } },
 497                                             (union drbd_state) { { .susp_fen = 0 } },
 498                                             CS_VERBOSE | CS_HARD | CS_DC_SUSP);
 499                         /* We are no longer suspended due to the fencing policy.
 500                          * We may still be suspended due to the on-no-data-accessible policy.
 501                          * If that was OND_IO_ERROR, fail pending requests. */
 502                         if (!resource_is_supended(resource))
 503                                 _tl_restart(connection, CONNECTION_LOST_WHILE_PENDING);
 504                 }
 505                 /* Else: in case we raced with a connection handshake,
 506                  * let the handshake figure out if we maybe can RESEND,
 507                  * and do not resume/fail pending requests here.
 508                  * Worst case is we stay suspended for now, which may be
 509                  * resolved by either re-establishing the replication link, or
 510                  * the next link failure, or eventually the administrator.  */
 511                 spin_unlock_irq(&resource->req_lock);
 512                 return false;
 513
 514         case FP_DONT_CARE:
 515                 return true;
 516         default: ;
 517         }
 518
 519         r = conn_khelper(connection, "fence-peer");
 520
 521         switch ((r>>8) & 0xff) {
 522         case P_INCONSISTENT: /* peer is inconsistent */
 523                 ex_to_string = "peer is inconsistent or worse";
 524                 mask.pdsk = D_MASK;
 525                 val.pdsk = D_INCONSISTENT;
 526                 break;
 527         case P_OUTDATED: /* peer got outdated, or was already outdated */
 528                 ex_to_string = "peer was fenced";
 529                 mask.pdsk = D_MASK;
 530                 val.pdsk = D_OUTDATED;
 531                 break;
 532         case P_DOWN: /* peer was down */
 533                 if (conn_highest_disk(connection) == D_UP_TO_DATE) {
 534                         /* we will(have) create(d) a new UUID anyways... */
 535                         ex_to_string = "peer is unreachable, assumed to be dead";
 536                         mask.pdsk = D_MASK;
 537                         val.pdsk = D_OUTDATED;
 538                 } else {
 539                         ex_to_string = "peer unreachable, doing nothing since disk != UpToDate";
 540                 }
 541                 break;
 542         case P_PRIMARY: /* Peer is primary, voluntarily outdate myself.
 543                  * This is useful when an unconnected R_SECONDARY is asked to
 544                  * become R_PRIMARY, but finds the other peer being active. */
 545                 ex_to_string = "peer is active";
 546                 drbd_warn(connection, "Peer is primary, outdating myself.\n");
 547                 mask.disk = D_MASK;
 548                 val.disk = D_OUTDATED;
 549                 break;
 550         case P_FENCING:
 551                 /* THINK: do we need to handle this
 552                  * like case 4, or more like case 5? */
 553                 if (fp != FP_STONITH)
 554                         drbd_err(connection, "fence-peer() = 7 && fencing != Stonith !!!\n");
 555                 ex_to_string = "peer was stonithed";
 556                 mask.pdsk = D_MASK;
 557                 val.pdsk = D_OUTDATED;
 558                 break;
 559         default:
 560                 /* The script is broken ... */
 561                 drbd_err(connection, "fence-peer helper broken, returned %d\n", (r>>8)&0xff);
 562                 return false; /* Eventually leave IO frozen */
 563         }
 564
 565         drbd_info(connection, "fence-peer helper returned %d (%s)\n",
 566                   (r>>8) & 0xff, ex_to_string);
 567
 568         /* Not using
 569            conn_request_state(connection, mask, val, CS_VERBOSE);
 570            here, because we might were able to re-establish the connection in the
 571            meantime. */
 572         spin_lock_irq(&resource->req_lock);
 573         if (connection->cstate < C_WF_REPORT_PARAMS && !test_bit(STATE_SENT, &connection->flags)) {
 574                 if (connection->connect_cnt != connect_cnt)
 575                         /* In case the connection was established and droped
 576                            while the fence-peer handler was running, ignore it */
 577                         drbd_info(connection, "Ignoring fence-peer exit code\n");
 578                 else
 579                         _conn_request_state(connection, mask, val, CS_VERBOSE);
 580         }
 581         spin_unlock_irq(&resource->req_lock);
 582
 583         return conn_highest_pdsk(connection) <= D_OUTDATED;
 584 }
 585
 586 static int _try_outdate_peer_async(void *data)
 587 {
 588         struct drbd_connection *connection = (struct drbd_connection *)data;
 589
 590         conn_try_outdate_peer(connection);
 591
 592         kref_put(&connection->kref, drbd_destroy_connection);
 593         return 0;
 594 }
 595
 596 void conn_try_outdate_peer_async(struct drbd_connection *connection)
 597 {
 598         struct task_struct *opa;
 599
 600         kref_get(&connection->kref);
 601         /* We may have just sent a signal to this thread
 602          * to get it out of some blocking network function.
 603          * Clear signals; otherwise kthread_run(), which internally uses
 604          * wait_on_completion_killable(), will mistake our pending signal
 605          * for a new fatal signal and fail. */
 606         flush_signals(current);
 607         opa = kthread_run(_try_outdate_peer_async, connection, "drbd_async_h");
 608         if (IS_ERR(opa)) {
 609                 drbd_err(connection, "out of mem, failed to invoke fence-peer helper\n");
 610                 kref_put(&connection->kref, drbd_destroy_connection);
 611         }
 612 }
 613
 614 enum drbd_state_rv
 615 drbd_set_role(struct drbd_device *const device, enum drbd_role new_role, int force)
 616 {
 617         struct drbd_peer_device *const peer_device = first_peer_device(device);
 618         struct drbd_connection *const connection = peer_device ? peer_device->connection : NULL;
 619         const int max_tries = 4;
 620         enum drbd_state_rv rv = SS_UNKNOWN_ERROR;
 621         struct net_conf *nc;
 622         int try = 0;
 623         int forced = 0;
 624         union drbd_state mask, val;
 625
 626         if (new_role == R_PRIMARY) {
 627                 struct drbd_connection *connection;
 628
 629                 /* Detect dead peers as soon as possible.  */
 630
 631                 rcu_read_lock();
 632                 for_each_connection(connection, device->resource)
 633                         request_ping(connection);
 634                 rcu_read_unlock();
 635         }
 636
 637         mutex_lock(device->state_mutex);
 638
 639         mask.i = 0; mask.role = R_MASK;
 640         val.i  = 0; val.role  = new_role;
 641
 642         while (try++ < max_tries) {
 643                 rv = _drbd_request_state_holding_state_mutex(device, mask, val, CS_WAIT_COMPLETE);
 644
 645                 /* in case we first succeeded to outdate,
 646                  * but now suddenly could establish a connection */
 647                 if (rv == SS_CW_FAILED_BY_PEER && mask.pdsk != 0) {
 648                         val.pdsk = 0;
 649                         mask.pdsk = 0;
 650                         continue;
 651                 }
 652
 653                 if (rv == SS_NO_UP_TO_DATE_DISK && force &&
 654                     (device->state.disk < D_UP_TO_DATE &&
 655                      device->state.disk >= D_INCONSISTENT)) {
 656                         mask.disk = D_MASK;
 657                         val.disk  = D_UP_TO_DATE;
 658                         forced = 1;
 659                         continue;
 660                 }
 661
 662                 if (rv == SS_NO_UP_TO_DATE_DISK &&
 663                     device->state.disk == D_CONSISTENT && mask.pdsk == 0) {
 664                         D_ASSERT(device, device->state.pdsk == D_UNKNOWN);
 665
 666                         if (conn_try_outdate_peer(connection)) {
 667                                 val.disk = D_UP_TO_DATE;
 668                                 mask.disk = D_MASK;
 669                         }
 670                         continue;
 671                 }
 672
 673                 if (rv == SS_NOTHING_TO_DO)
 674                         goto out;
 675                 if (rv == SS_PRIMARY_NOP && mask.pdsk == 0) {
 676                         if (!conn_try_outdate_peer(connection) && force) {
 677                                 drbd_warn(device, "Forced into split brain situation!\n");
 678                                 mask.pdsk = D_MASK;
 679                                 val.pdsk  = D_OUTDATED;
 680
 681                         }
 682                         continue;
 683                 }
 684                 if (rv == SS_TWO_PRIMARIES) {
 685                         /* Maybe the peer is detected as dead very soon...
 686                            retry at most once more in this case. */
 687                         if (try < max_tries) {
 688                                 int timeo;
 689                                 try = max_tries - 1;
 690                                 rcu_read_lock();
 691                                 nc = rcu_dereference(connection->net_conf);
 692                                 timeo = nc ? (nc->ping_timeo + 1) * HZ / 10 : 1;
 693                                 rcu_read_unlock();
 694                                 schedule_timeout_interruptible(timeo);
 695                         }
 696                         continue;
 697                 }
 698                 if (rv < SS_SUCCESS) {
 699                         rv = _drbd_request_state(device, mask, val,
 700                                                 CS_VERBOSE + CS_WAIT_COMPLETE);
 701                         if (rv < SS_SUCCESS)
 702                                 goto out;
 703                 }
 704                 break;
 705         }
 706
 707         if (rv < SS_SUCCESS)
 708                 goto out;
 709
 710         if (forced)
 711                 drbd_warn(device, "Forced to consider local data as UpToDate!\n");
 712
 713         /* Wait until nothing is on the fly :) */
 714         wait_event(device->misc_wait, atomic_read(&device->ap_pending_cnt) == 0);
 715
 716         /* FIXME also wait for all pending P_BARRIER_ACK? */
 717
 718         if (new_role == R_SECONDARY) {
 719                 if (get_ldev(device)) {
 720                         device->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
 721                         put_ldev(device);
 722                 }
 723         } else {
 724                 mutex_lock(&device->resource->conf_update);
 725                 nc = connection->net_conf;
 726                 if (nc)
 727                         nc->discard_my_data = 0; /* without copy; single bit op is atomic */
 728                 mutex_unlock(&device->resource->conf_update);
 729
 730                 if (get_ldev(device)) {
 731                         if (((device->state.conn < C_CONNECTED ||
 732                                device->state.pdsk <= D_FAILED)
 733                               && device->ldev->md.uuid[UI_BITMAP] == 0) || forced)
 734                                 drbd_uuid_new_current(device);
 735
 736                         device->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
 737                         put_ldev(device);
 738                 }
 739         }
 740
 741         /* writeout of activity log covered areas of the bitmap
 742          * to stable storage done in after state change already */
 743
 744         if (device->state.conn >= C_WF_REPORT_PARAMS) {
 745                 /* if this was forced, we should consider sync */
 746                 if (forced)
 747                         drbd_send_uuids(peer_device);
 748                 drbd_send_current_state(peer_device);
 749         }
 750
 751         drbd_md_sync(device);
 752         set_disk_ro(device->vdisk, new_role == R_SECONDARY);
 753         kobject_uevent(&disk_to_dev(device->vdisk)->kobj, KOBJ_CHANGE);
 754 out:
 755         mutex_unlock(device->state_mutex);
 756         return rv;
 757 }
 758
 759 static const char *from_attrs_err_to_txt(int err)
 760 {
 761         return  err == -ENOMSG ? "required attribute missing" :
 762                 err == -EOPNOTSUPP ? "unknown mandatory attribute" :
 763                 err == -EEXIST ? "can not change invariant setting" :
 764                 "invalid attribute value";
 765 }
 766
 767 int drbd_adm_set_role(struct sk_buff *skb, struct genl_info *info)
 768 {
 769         struct drbd_config_context adm_ctx;
 770         struct set_role_parms parms;
 771         int err;
 772         enum drbd_ret_code retcode;
 773         enum drbd_state_rv rv;
 774
 775         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
 776         if (!adm_ctx.reply_skb)
 777                 return retcode;
 778         if (retcode != NO_ERROR)
 779                 goto out;
 780
 781         memset(&parms, 0, sizeof(parms));
 782         if (info->attrs[DRBD_NLA_SET_ROLE_PARMS]) {
 783                 err = set_role_parms_from_attrs(&parms, info);
 784                 if (err) {
 785                         retcode = ERR_MANDATORY_TAG;
 786                         drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
 787                         goto out;
 788                 }
 789         }
 790         genl_unlock();
 791         mutex_lock(&adm_ctx.resource->adm_mutex);
 792
 793         if (info->genlhdr->cmd == DRBD_ADM_PRIMARY)
 794                 rv = drbd_set_role(adm_ctx.device, R_PRIMARY, parms.assume_uptodate);
 795         else
 796                 rv = drbd_set_role(adm_ctx.device, R_SECONDARY, 0);
 797
 798         mutex_unlock(&adm_ctx.resource->adm_mutex);
 799         genl_lock();
 800         drbd_adm_finish(&adm_ctx, info, rv);
 801         return 0;
 802 out:
 803         drbd_adm_finish(&adm_ctx, info, retcode);
 804         return 0;
 805 }
 806
 807 /* Initializes the md.*_offset members, so we are able to find
 808  * the on disk meta data.
 809  *
 810  * We currently have two possible layouts:
 811  * external:
 812  *   |----------- md_size_sect ------------------|
 813  *   [ 4k superblock ][ activity log ][  Bitmap  ]
 814  *   | al_offset == 8 |
 815  *   | bm_offset = al_offset + X      |
 816  *  ==> bitmap sectors = md_size_sect - bm_offset
 817  *
 818  * internal:
 819  *            |----------- md_size_sect ------------------|
 820  * [data.....][  Bitmap  ][ activity log ][ 4k superblock ]
 821  *                        | al_offset < 0 |
 822  *            | bm_offset = al_offset - Y |
 823  *  ==> bitmap sectors = Y = al_offset - bm_offset
 824  *
 825  *  Activity log size used to be fixed 32kB,
 826  *  but is about to become configurable.
 827  */
 828 static void drbd_md_set_sector_offsets(struct drbd_device *device,
 829                                        struct drbd_backing_dev *bdev)
 830 {
 831         sector_t md_size_sect = 0;
 832         unsigned int al_size_sect = bdev->md.al_size_4k * 8;
 833
 834         bdev->md.md_offset = drbd_md_ss(bdev);
 835
 836         switch (bdev->md.meta_dev_idx) {
 837         default:
 838                 /* v07 style fixed size indexed meta data */
 839                 bdev->md.md_size_sect = MD_128MB_SECT;
 840                 bdev->md.al_offset = MD_4kB_SECT;
 841                 bdev->md.bm_offset = MD_4kB_SECT + al_size_sect;
 842                 break;
 843         case DRBD_MD_INDEX_FLEX_EXT:
 844                 /* just occupy the full device; unit: sectors */
 845                 bdev->md.md_size_sect = drbd_get_capacity(bdev->md_bdev);
 846                 bdev->md.al_offset = MD_4kB_SECT;
 847                 bdev->md.bm_offset = MD_4kB_SECT + al_size_sect;
 848                 break;
 849         case DRBD_MD_INDEX_INTERNAL:
 850         case DRBD_MD_INDEX_FLEX_INT:
 851                 /* al size is still fixed */
 852                 bdev->md.al_offset = -al_size_sect;
 853                 /* we need (slightly less than) ~ this much bitmap sectors: */
 854                 md_size_sect = drbd_get_capacity(bdev->backing_bdev);
 855                 md_size_sect = ALIGN(md_size_sect, BM_SECT_PER_EXT);
 856                 md_size_sect = BM_SECT_TO_EXT(md_size_sect);
 857                 md_size_sect = ALIGN(md_size_sect, 8);
 858
 859                 /* plus the "drbd meta data super block",
 860                  * and the activity log; */
 861                 md_size_sect += MD_4kB_SECT + al_size_sect;
 862
 863                 bdev->md.md_size_sect = md_size_sect;
 864                 /* bitmap offset is adjusted by 'super' block size */
 865                 bdev->md.bm_offset   = -md_size_sect + MD_4kB_SECT;
 866                 break;
 867         }
 868 }
 869
 870 /* input size is expected to be in KB */
 871 char *ppsize(char *buf, unsigned long long size)
 872 {
 873         /* Needs 9 bytes at max including trailing NUL:
 874          * -1ULL ==> "16384 EB" */
 875         static char units[] = { 'K', 'M', 'G', 'T', 'P', 'E' };
 876         int base = 0;
 877         while (size >= 10000 && base < sizeof(units)-1) {
 878                 /* shift + round */
 879                 size = (size >> 10) + !!(size & (1<<9));
 880                 base++;
 881         }
 882         sprintf(buf, "%u %cB", (unsigned)size, units[base]);
 883
 884         return buf;
 885 }
 886
 887 /* there is still a theoretical deadlock when called from receiver
 888  * on an D_INCONSISTENT R_PRIMARY:
 889  *  remote READ does inc_ap_bio, receiver would need to receive answer
 890  *  packet from remote to dec_ap_bio again.
 891  *  receiver receive_sizes(), comes here,
 892  *  waits for ap_bio_cnt == 0. -> deadlock.
 893  * but this cannot happen, actually, because:
 894  *  R_PRIMARY D_INCONSISTENT, and peer's disk is unreachable
 895  *  (not connected, or bad/no disk on peer):
 896  *  see drbd_fail_request_early, ap_bio_cnt is zero.
 897  *  R_PRIMARY D_INCONSISTENT, and C_SYNC_TARGET:
 898  *  peer may not initiate a resize.
 899  */
 900 /* Note these are not to be confused with
 901  * drbd_adm_suspend_io/drbd_adm_resume_io,
 902  * which are (sub) state changes triggered by admin (drbdsetup),
 903  * and can be long lived.
 904  * This changes an device->flag, is triggered by drbd internals,
 905  * and should be short-lived. */
 906 /* It needs to be a counter, since multiple threads might
 907    independently suspend and resume IO. */
 908 void drbd_suspend_io(struct drbd_device *device)
 909 {
 910         atomic_inc(&device->suspend_cnt);
 911         if (drbd_suspended(device))
 912                 return;
 913         wait_event(device->misc_wait, !atomic_read(&device->ap_bio_cnt));
 914 }
 915
 916 void drbd_resume_io(struct drbd_device *device)
 917 {
 918         if (atomic_dec_and_test(&device->suspend_cnt))
 919                 wake_up(&device->misc_wait);
 920 }
 921
 922 /*
 923  * drbd_determine_dev_size() -  Sets the right device size obeying all constraints
 924  * @device:     DRBD device.
 925  *
 926  * Returns 0 on success, negative return values indicate errors.
 927  * You should call drbd_md_sync() after calling this function.
 928  */
 929 enum determine_dev_size
 930 drbd_determine_dev_size(struct drbd_device *device, enum dds_flags flags, struct resize_parms *rs) __must_hold(local)
 931 {
 932         struct md_offsets_and_sizes {
 933                 u64 last_agreed_sect;
 934                 u64 md_offset;
 935                 s32 al_offset;
 936                 s32 bm_offset;
 937                 u32 md_size_sect;
 938
 939                 u32 al_stripes;
 940                 u32 al_stripe_size_4k;
 941         } prev;
 942         sector_t u_size, size;
 943         struct drbd_md *md = &device->ldev->md;
 944         void *buffer;
 945
 946         int md_moved, la_size_changed;
 947         enum determine_dev_size rv = DS_UNCHANGED;
 948
 949         /* We may change the on-disk offsets of our meta data below.  Lock out
 950          * anything that may cause meta data IO, to avoid acting on incomplete
 951          * layout changes or scribbling over meta data that is in the process
 952          * of being moved.
 953          *
 954          * Move is not exactly correct, btw, currently we have all our meta
 955          * data in core memory, to "move" it we just write it all out, there
 956          * are no reads. */
 957         drbd_suspend_io(device);
 958         buffer = drbd_md_get_buffer(device, __func__); /* Lock meta-data IO */
 959         if (!buffer) {
 960                 drbd_resume_io(device);
 961                 return DS_ERROR;
 962         }
 963
 964         /* remember current offset and sizes */
 965         prev.last_agreed_sect = md->la_size_sect;
 966         prev.md_offset = md->md_offset;
 967         prev.al_offset = md->al_offset;
 968         prev.bm_offset = md->bm_offset;
 969         prev.md_size_sect = md->md_size_sect;
 970         prev.al_stripes = md->al_stripes;
 971         prev.al_stripe_size_4k = md->al_stripe_size_4k;
 972
 973         if (rs) {
 974                 /* rs is non NULL if we should change the AL layout only */
 975                 md->al_stripes = rs->al_stripes;
 976                 md->al_stripe_size_4k = rs->al_stripe_size / 4;
 977                 md->al_size_4k = (u64)rs->al_stripes * rs->al_stripe_size / 4;
 978         }
 979
 980         drbd_md_set_sector_offsets(device, device->ldev);
 981
 982         rcu_read_lock();
 983         u_size = rcu_dereference(device->ldev->disk_conf)->disk_size;
 984         rcu_read_unlock();
 985         size = drbd_new_dev_size(device, device->ldev, u_size, flags & DDSF_FORCED);
 986
 987         if (size < prev.last_agreed_sect) {
 988                 if (rs && u_size == 0) {
 989                         /* Remove "rs &&" later. This check should always be active, but
 990                            right now the receiver expects the permissive behavior */
 991                         drbd_warn(device, "Implicit shrink not allowed. "
 992                                  "Use --size=%llus for explicit shrink.\n",
 993                                  (unsigned long long)size);
 994                         rv = DS_ERROR_SHRINK;
 995                 }
 996                 if (u_size > size)
 997                         rv = DS_ERROR_SPACE_MD;
 998                 if (rv != DS_UNCHANGED)
 999                         goto err_out;
1000         }
1001
1002         if (get_capacity(device->vdisk) != size ||
1003             drbd_bm_capacity(device) != size) {
1004                 int err;
1005                 err = drbd_bm_resize(device, size, !(flags & DDSF_NO_RESYNC));
1006                 if (unlikely(err)) {
1007                         /* currently there is only one error: ENOMEM! */
1008                         size = drbd_bm_capacity(device);
1009                         if (size == 0) {
1010                                 drbd_err(device, "OUT OF MEMORY! "
1011                                     "Could not allocate bitmap!\n");
1012                         } else {
1013                                 drbd_err(device, "BM resizing failed. "
1014                                     "Leaving size unchanged\n");
1015                         }
1016                         rv = DS_ERROR;
1017                 }
1018                 /* racy, see comments above. */
1019                 drbd_set_my_capacity(device, size);
1020                 md->la_size_sect = size;
1021         }
1022         if (rv <= DS_ERROR)
1023                 goto err_out;
1024
1025         la_size_changed = (prev.last_agreed_sect != md->la_size_sect);
1026
1027         md_moved = prev.md_offset    != md->md_offset
1028                 || prev.md_size_sect != md->md_size_sect;
1029
1030         if (la_size_changed || md_moved || rs) {
1031                 u32 prev_flags;
1032
1033                 /* We do some synchronous IO below, which may take some time.
1034                  * Clear the timer, to avoid scary "timer expired!" messages,
1035                  * "Superblock" is written out at least twice below, anyways. */
1036                 del_timer(&device->md_sync_timer);
1037
1038                 /* We won't change the "al-extents" setting, we just may need
1039                  * to move the on-disk location of the activity log ringbuffer.
1040                  * Lock for transaction is good enough, it may well be "dirty"
1041                  * or even "starving". */
1042                 wait_event(device->al_wait, lc_try_lock_for_transaction(device->act_log));
1043
1044                 /* mark current on-disk bitmap and activity log as unreliable */
1045                 prev_flags = md->flags;
1046                 md->flags |= MDF_FULL_SYNC | MDF_AL_DISABLED;
1047                 drbd_md_write(device, buffer);
1048
1049                 drbd_al_initialize(device, buffer);
1050
1051                 drbd_info(device, "Writing the whole bitmap, %s\n",
1052                          la_size_changed && md_moved ? "size changed and md moved" :
1053                          la_size_changed ? "size changed" : "md moved");
1054                 /* next line implicitly does drbd_suspend_io()+drbd_resume_io() */
1055                 drbd_bitmap_io(device, md_moved ? &drbd_bm_write_all : &drbd_bm_write,
1056                                "size changed", BM_LOCKED_MASK, NULL);
1057
1058                 /* on-disk bitmap and activity log is authoritative again
1059                  * (unless there was an IO error meanwhile...) */
1060                 md->flags = prev_flags;
1061                 drbd_md_write(device, buffer);
1062
1063                 if (rs)
1064                         drbd_info(device, "Changed AL layout to al-stripes = %d, al-stripe-size-kB = %d\n",
1065                                   md->al_stripes, md->al_stripe_size_4k * 4);
1066         }
1067
1068         if (size > prev.last_agreed_sect)
1069                 rv = prev.last_agreed_sect ? DS_GREW : DS_GREW_FROM_ZERO;
1070         if (size < prev.last_agreed_sect)
1071                 rv = DS_SHRUNK;
1072
1073         if (0) {
1074         err_out:
1075                 /* restore previous offset and sizes */
1076                 md->la_size_sect = prev.last_agreed_sect;
1077                 md->md_offset = prev.md_offset;
1078                 md->al_offset = prev.al_offset;
1079                 md->bm_offset = prev.bm_offset;
1080                 md->md_size_sect = prev.md_size_sect;
1081                 md->al_stripes = prev.al_stripes;
1082                 md->al_stripe_size_4k = prev.al_stripe_size_4k;
1083                 md->al_size_4k = (u64)prev.al_stripes * prev.al_stripe_size_4k;
1084         }
1085         lc_unlock(device->act_log);
1086         wake_up(&device->al_wait);
1087         drbd_md_put_buffer(device);
1088         drbd_resume_io(device);
1089
1090         return rv;
1091 }
1092
1093 sector_t
1094 drbd_new_dev_size(struct drbd_device *device, struct drbd_backing_dev *bdev,
1095                   sector_t u_size, int assume_peer_has_space)
1096 {
1097         sector_t p_size = device->p_size;   /* partner's disk size. */
1098         sector_t la_size_sect = bdev->md.la_size_sect; /* last agreed size. */
1099         sector_t m_size; /* my size */
1100         sector_t size = 0;
1101
1102         m_size = drbd_get_max_capacity(bdev);
1103
1104         if (device->state.conn < C_CONNECTED && assume_peer_has_space) {
1105                 drbd_warn(device, "Resize while not connected was forced by the user!\n");
1106                 p_size = m_size;
1107         }
1108
1109         if (p_size && m_size) {
1110                 size = min_t(sector_t, p_size, m_size);
1111         } else {
1112                 if (la_size_sect) {
1113                         size = la_size_sect;
1114                         if (m_size && m_size < size)
1115                                 size = m_size;
1116                         if (p_size && p_size < size)
1117                                 size = p_size;
1118                 } else {
1119                         if (m_size)
1120                                 size = m_size;
1121                         if (p_size)
1122                                 size = p_size;
1123                 }
1124         }
1125
1126         if (size == 0)
1127                 drbd_err(device, "Both nodes diskless!\n");
1128
1129         if (u_size) {
1130                 if (u_size > size)
1131                         drbd_err(device, "Requested disk size is too big (%lu > %lu)\n",
1132                             (unsigned long)u_size>>1, (unsigned long)size>>1);
1133                 else
1134                         size = u_size;
1135         }
1136
1137         return size;
1138 }
1139
1140 /*
1141  * drbd_check_al_size() - Ensures that the AL is of the right size
1142  * @device:     DRBD device.
1143  *
1144  * Returns -EBUSY if current al lru is still used, -ENOMEM when allocation
1145  * failed, and 0 on success. You should call drbd_md_sync() after you called
1146  * this function.
1147  */
1148 static int drbd_check_al_size(struct drbd_device *device, struct disk_conf *dc)
1149 {
1150         struct lru_cache *n, *t;
1151         struct lc_element *e;
1152         unsigned int in_use;
1153         int i;
1154
1155         if (device->act_log &&
1156             device->act_log->nr_elements == dc->al_extents)
1157                 return 0;
1158
1159         in_use = 0;
1160         t = device->act_log;
1161         n = lc_create("act_log", drbd_al_ext_cache, AL_UPDATES_PER_TRANSACTION,
1162                 dc->al_extents, sizeof(struct lc_element), 0);
1163
1164         if (n == NULL) {
1165                 drbd_err(device, "Cannot allocate act_log lru!\n");
1166                 return -ENOMEM;
1167         }
1168         spin_lock_irq(&device->al_lock);
1169         if (t) {
1170                 for (i = 0; i < t->nr_elements; i++) {
1171                         e = lc_element_by_index(t, i);
1172                         if (e->refcnt)
1173                                 drbd_err(device, "refcnt(%d)==%d\n",
1174                                     e->lc_number, e->refcnt);
1175                         in_use += e->refcnt;
1176                 }
1177         }
1178         if (!in_use)
1179                 device->act_log = n;
1180         spin_unlock_irq(&device->al_lock);
1181         if (in_use) {
1182                 drbd_err(device, "Activity log still in use!\n");
1183                 lc_destroy(n);
1184                 return -EBUSY;
1185         } else {
1186                 lc_destroy(t);
1187         }
1188         drbd_md_mark_dirty(device); /* we changed device->act_log->nr_elemens */
1189         return 0;
1190 }
1191
1192 static void blk_queue_discard_granularity(struct request_queue *q, unsigned int granularity)
1193 {
1194         q->limits.discard_granularity = granularity;
1195 }
1196
1197 static unsigned int drbd_max_discard_sectors(struct drbd_connection *connection)
1198 {
1199         /* when we introduced REQ_WRITE_SAME support, we also bumped
1200          * our maximum supported batch bio size used for discards. */
1201         if (connection->agreed_features & DRBD_FF_WSAME)
1202                 return DRBD_MAX_BBIO_SECTORS;
1203         /* before, with DRBD <= 8.4.6, we only allowed up to one AL_EXTENT_SIZE. */
1204         return AL_EXTENT_SIZE >> 9;
1205 }
1206
1207 static void decide_on_discard_support(struct drbd_device *device,
1208                 struct drbd_backing_dev *bdev)
1209 {
1210         struct drbd_connection *connection =
1211                 first_peer_device(device)->connection;
1212         struct request_queue *q = device->rq_queue;
1213         unsigned int max_discard_sectors;
1214
1215         if (bdev && !bdev_max_discard_sectors(bdev->backing_bdev))
1216                 goto not_supported;
1217
1218         if (connection->cstate >= C_CONNECTED &&
1219             !(connection->agreed_features & DRBD_FF_TRIM)) {
1220                 drbd_info(connection,
1221                         "peer DRBD too old, does not support TRIM: disabling discards\n");
1222                 goto not_supported;
1223         }
1224
1225         /*
1226          * We don't care for the granularity, really.
1227          *
1228          * Stacking limits below should fix it for the local device.  Whether or
1229          * not it is a suitable granularity on the remote device is not our
1230          * problem, really. If you care, you need to use devices with similar
1231          * topology on all peers.
1232          */
1233         blk_queue_discard_granularity(q, 512);
1234         max_discard_sectors = drbd_max_discard_sectors(connection);
1235         blk_queue_max_discard_sectors(q, max_discard_sectors);
1236         blk_queue_max_write_zeroes_sectors(q, max_discard_sectors);
1237         return;
1238
1239 not_supported:
1240         blk_queue_discard_granularity(q, 0);
1241         blk_queue_max_discard_sectors(q, 0);
1242 }
1243
1244 static void fixup_write_zeroes(struct drbd_device *device, struct request_queue *q)
1245 {
1246         /* Fixup max_write_zeroes_sectors after blk_stack_limits():
1247          * if we can handle "zeroes" efficiently on the protocol,
1248          * we want to do that, even if our backend does not announce
1249          * max_write_zeroes_sectors itself. */
1250         struct drbd_connection *connection = first_peer_device(device)->connection;
1251         /* If the peer announces WZEROES support, use it.  Otherwise, rather
1252          * send explicit zeroes than rely on some discard-zeroes-data magic. */
1253         if (connection->agreed_features & DRBD_FF_WZEROES)
1254                 q->limits.max_write_zeroes_sectors = DRBD_MAX_BBIO_SECTORS;
1255         else
1256                 q->limits.max_write_zeroes_sectors = 0;
1257 }
1258
1259 static void fixup_discard_support(struct drbd_device *device, struct request_queue *q)
1260 {
1261         unsigned int max_discard = device->rq_queue->limits.max_discard_sectors;
1262         unsigned int discard_granularity =
1263                 device->rq_queue->limits.discard_granularity >> SECTOR_SHIFT;
1264
1265         if (discard_granularity > max_discard) {
1266                 blk_queue_discard_granularity(q, 0);
1267                 blk_queue_max_discard_sectors(q, 0);
1268         }
1269 }
1270
1271 static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backing_dev *bdev,
1272                                    unsigned int max_bio_size, struct o_qlim *o)
1273 {
1274         struct request_queue * const q = device->rq_queue;
1275         unsigned int max_hw_sectors = max_bio_size >> 9;
1276         unsigned int max_segments = 0;
1277         struct request_queue *b = NULL;
1278         struct disk_conf *dc;
1279
1280         if (bdev) {
1281                 b = bdev->backing_bdev->bd_disk->queue;
1282
1283                 max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9);
1284                 rcu_read_lock();
1285                 dc = rcu_dereference(device->ldev->disk_conf);
1286                 max_segments = dc->max_bio_bvecs;
1287                 rcu_read_unlock();
1288
1289                 blk_set_stacking_limits(&q->limits);
1290         }
1291
1292         blk_queue_max_hw_sectors(q, max_hw_sectors);
1293         /* This is the workaround for "bio would need to, but cannot, be split" */
1294         blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
1295         blk_queue_segment_boundary(q, PAGE_SIZE-1);
1296         decide_on_discard_support(device, bdev);
1297
1298         if (b) {
1299                 blk_stack_limits(&q->limits, &b->limits, 0);
1300                 disk_update_readahead(device->vdisk);
1301         }
1302         fixup_write_zeroes(device, q);
1303         fixup_discard_support(device, q);
1304 }
1305
1306 void drbd_reconsider_queue_parameters(struct drbd_device *device, struct drbd_backing_dev *bdev, struct o_qlim *o)
1307 {
1308         unsigned int now, new, local, peer;
1309
1310         now = queue_max_hw_sectors(device->rq_queue) << 9;
1311         local = device->local_max_bio_size; /* Eventually last known value, from volatile memory */
1312         peer = device->peer_max_bio_size; /* Eventually last known value, from meta data */
1313
1314         if (bdev) {
1315                 local = queue_max_hw_sectors(bdev->backing_bdev->bd_disk->queue) << 9;
1316                 device->local_max_bio_size = local;
1317         }
1318         local = min(local, DRBD_MAX_BIO_SIZE);
1319
1320         /* We may ignore peer limits if the peer is modern enough.
1321            Because new from 8.3.8 onwards the peer can use multiple
1322            BIOs for a single peer_request */
1323         if (device->state.conn >= C_WF_REPORT_PARAMS) {
1324                 if (first_peer_device(device)->connection->agreed_pro_version < 94)
1325                         peer = min(device->peer_max_bio_size, DRBD_MAX_SIZE_H80_PACKET);
1326                         /* Correct old drbd (up to 8.3.7) if it believes it can do more than 32KiB */
1327                 else if (first_peer_device(device)->connection->agreed_pro_version == 94)
1328                         peer = DRBD_MAX_SIZE_H80_PACKET;
1329                 else if (first_peer_device(device)->connection->agreed_pro_version < 100)
1330                         peer = DRBD_MAX_BIO_SIZE_P95;  /* drbd 8.3.8 onwards, before 8.4.0 */
1331                 else
1332                         peer = DRBD_MAX_BIO_SIZE;
1333
1334                 /* We may later detach and re-attach on a disconnected Primary.
1335                  * Avoid this setting to jump back in that case.
1336                  * We want to store what we know the peer DRBD can handle,
1337                  * not what the peer IO backend can handle. */
1338                 if (peer > device->peer_max_bio_size)
1339                         device->peer_max_bio_size = peer;
1340         }
1341         new = min(local, peer);
1342
1343         if (device->state.role == R_PRIMARY && new < now)
1344                 drbd_err(device, "ASSERT FAILED new < now; (%u < %u)\n", new, now);
1345
1346         if (new != now)
1347                 drbd_info(device, "max BIO size = %u\n", new);
1348
1349         drbd_setup_queue_param(device, bdev, new, o);
1350 }
1351
1352 /* Starts the worker thread */
1353 static void conn_reconfig_start(struct drbd_connection *connection)
1354 {
1355         drbd_thread_start(&connection->worker);
1356         drbd_flush_workqueue(&connection->sender_work);
1357 }
1358
1359 /* if still unconfigured, stops worker again. */
1360 static void conn_reconfig_done(struct drbd_connection *connection)
1361 {
1362         bool stop_threads;
1363         spin_lock_irq(&connection->resource->req_lock);
1364         stop_threads = conn_all_vols_unconf(connection) &&
1365                 connection->cstate == C_STANDALONE;
1366         spin_unlock_irq(&connection->resource->req_lock);
1367         if (stop_threads) {
1368                 /* ack_receiver thread and ack_sender workqueue are implicitly
1369                  * stopped by receiver in conn_disconnect() */
1370                 drbd_thread_stop(&connection->receiver);
1371                 drbd_thread_stop(&connection->worker);
1372         }
1373 }
1374
1375 /* Make sure IO is suspended before calling this function(). */
1376 static void drbd_suspend_al(struct drbd_device *device)
1377 {
1378         int s = 0;
1379
1380         if (!lc_try_lock(device->act_log)) {
1381                 drbd_warn(device, "Failed to lock al in drbd_suspend_al()\n");
1382                 return;
1383         }
1384
1385         drbd_al_shrink(device);
1386         spin_lock_irq(&device->resource->req_lock);
1387         if (device->state.conn < C_CONNECTED)
1388                 s = !test_and_set_bit(AL_SUSPENDED, &device->flags);
1389         spin_unlock_irq(&device->resource->req_lock);
1390         lc_unlock(device->act_log);
1391
1392         if (s)
1393                 drbd_info(device, "Suspended AL updates\n");
1394 }
1395
1396
1397 static bool should_set_defaults(struct genl_info *info)
1398 {
1399         struct drbd_genlmsghdr *dh = genl_info_userhdr(info);
1400
1401         return 0 != (dh->flags & DRBD_GENL_F_SET_DEFAULTS);
1402 }
1403
1404 static unsigned int drbd_al_extents_max(struct drbd_backing_dev *bdev)
1405 {
1406         /* This is limited by 16 bit "slot" numbers,
1407          * and by available on-disk context storage.
1408          *
1409          * Also (u16)~0 is special (denotes a "free" extent).
1410          *
1411          * One transaction occupies one 4kB on-disk block,
1412          * we have n such blocks in the on disk ring buffer,
1413          * the "current" transaction may fail (n-1),
1414          * and there is 919 slot numbers context information per transaction.
1415          *
1416          * 72 transaction blocks amounts to more than 2**16 context slots,
1417          * so cap there first.
1418          */
1419         const unsigned int max_al_nr = DRBD_AL_EXTENTS_MAX;
1420         const unsigned int sufficient_on_disk =
1421                 (max_al_nr + AL_CONTEXT_PER_TRANSACTION -1)
1422                 /AL_CONTEXT_PER_TRANSACTION;
1423
1424         unsigned int al_size_4k = bdev->md.al_size_4k;
1425
1426         if (al_size_4k > sufficient_on_disk)
1427                 return max_al_nr;
1428
1429         return (al_size_4k - 1) * AL_CONTEXT_PER_TRANSACTION;
1430 }
1431
1432 static bool write_ordering_changed(struct disk_conf *a, struct disk_conf *b)
1433 {
1434         return  a->disk_barrier != b->disk_barrier ||
1435                 a->disk_flushes != b->disk_flushes ||
1436                 a->disk_drain != b->disk_drain;
1437 }
1438
1439 static void sanitize_disk_conf(struct drbd_device *device, struct disk_conf *disk_conf,
1440                                struct drbd_backing_dev *nbc)
1441 {
1442         struct block_device *bdev = nbc->backing_bdev;
1443
1444         if (disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
1445                 disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
1446         if (disk_conf->al_extents > drbd_al_extents_max(nbc))
1447                 disk_conf->al_extents = drbd_al_extents_max(nbc);
1448
1449         if (!bdev_max_discard_sectors(bdev)) {
1450                 if (disk_conf->rs_discard_granularity) {
1451                         disk_conf->rs_discard_granularity = 0; /* disable feature */
1452                         drbd_info(device, "rs_discard_granularity feature disabled\n");
1453                 }
1454         }
1455
1456         if (disk_conf->rs_discard_granularity) {
1457                 int orig_value = disk_conf->rs_discard_granularity;
1458                 sector_t discard_size = bdev_max_discard_sectors(bdev) << 9;
1459                 unsigned int discard_granularity = bdev_discard_granularity(bdev);
1460                 int remainder;
1461
1462                 if (discard_granularity > disk_conf->rs_discard_granularity)
1463                         disk_conf->rs_discard_granularity = discard_granularity;
1464
1465                 remainder = disk_conf->rs_discard_granularity %
1466                                 discard_granularity;
1467                 disk_conf->rs_discard_granularity += remainder;
1468
1469                 if (disk_conf->rs_discard_granularity > discard_size)
1470                         disk_conf->rs_discard_granularity = discard_size;
1471
1472                 if (disk_conf->rs_discard_granularity != orig_value)
1473                         drbd_info(device, "rs_discard_granularity changed to %d\n",
1474                                   disk_conf->rs_discard_granularity);
1475         }
1476 }
1477
1478 static int disk_opts_check_al_size(struct drbd_device *device, struct disk_conf *dc)
1479 {
1480         int err = -EBUSY;
1481
1482         if (device->act_log &&
1483             device->act_log->nr_elements == dc->al_extents)
1484                 return 0;
1485
1486         drbd_suspend_io(device);
1487         /* If IO completion is currently blocked, we would likely wait
1488          * "forever" for the activity log to become unused. So we don't. */
1489         if (atomic_read(&device->ap_bio_cnt))
1490                 goto out;
1491
1492         wait_event(device->al_wait, lc_try_lock(device->act_log));
1493         drbd_al_shrink(device);
1494         err = drbd_check_al_size(device, dc);
1495         lc_unlock(device->act_log);
1496         wake_up(&device->al_wait);
1497 out:
1498         drbd_resume_io(device);
1499         return err;
1500 }
1501
1502 int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
1503 {
1504         struct drbd_config_context adm_ctx;
1505         enum drbd_ret_code retcode;
1506         struct drbd_device *device;
1507         struct disk_conf *new_disk_conf, *old_disk_conf;
1508         struct fifo_buffer *old_plan = NULL, *new_plan = NULL;
1509         int err;
1510         unsigned int fifo_size;
1511
1512         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
1513         if (!adm_ctx.reply_skb)
1514                 return retcode;
1515         if (retcode != NO_ERROR)
1516                 goto finish;
1517
1518         device = adm_ctx.device;
1519         mutex_lock(&adm_ctx.resource->adm_mutex);
1520
1521         /* we also need a disk
1522          * to change the options on */
1523         if (!get_ldev(device)) {
1524                 retcode = ERR_NO_DISK;
1525                 goto out;
1526         }
1527
1528         new_disk_conf = kmalloc(sizeof(struct disk_conf), GFP_KERNEL);
1529         if (!new_disk_conf) {
1530                 retcode = ERR_NOMEM;
1531                 goto fail;
1532         }
1533
1534         mutex_lock(&device->resource->conf_update);
1535         old_disk_conf = device->ldev->disk_conf;
1536         *new_disk_conf = *old_disk_conf;
1537         if (should_set_defaults(info))
1538                 set_disk_conf_defaults(new_disk_conf);
1539
1540         err = disk_conf_from_attrs_for_change(new_disk_conf, info);
1541         if (err && err != -ENOMSG) {
1542                 retcode = ERR_MANDATORY_TAG;
1543                 drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
1544                 goto fail_unlock;
1545         }
1546
1547         if (!expect(device, new_disk_conf->resync_rate >= 1))
1548                 new_disk_conf->resync_rate = 1;
1549
1550         sanitize_disk_conf(device, new_disk_conf, device->ldev);
1551
1552         if (new_disk_conf->c_plan_ahead > DRBD_C_PLAN_AHEAD_MAX)
1553                 new_disk_conf->c_plan_ahead = DRBD_C_PLAN_AHEAD_MAX;
1554
1555         fifo_size = (new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ;
1556         if (fifo_size != device->rs_plan_s->size) {
1557                 new_plan = fifo_alloc(fifo_size);
1558                 if (!new_plan) {
1559                         drbd_err(device, "kmalloc of fifo_buffer failed");
1560                         retcode = ERR_NOMEM;
1561                         goto fail_unlock;
1562                 }
1563         }
1564
1565         err = disk_opts_check_al_size(device, new_disk_conf);
1566         if (err) {
1567                 /* Could be just "busy". Ignore?
1568                  * Introduce dedicated error code? */
1569                 drbd_msg_put_info(adm_ctx.reply_skb,
1570                         "Try again without changing current al-extents setting");
1571                 retcode = ERR_NOMEM;
1572                 goto fail_unlock;
1573         }
1574
1575         lock_all_resources();
1576         retcode = drbd_resync_after_valid(device, new_disk_conf->resync_after);
1577         if (retcode == NO_ERROR) {
1578                 rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
1579                 drbd_resync_after_changed(device);
1580         }
1581         unlock_all_resources();
1582
1583         if (retcode != NO_ERROR)
1584                 goto fail_unlock;
1585
1586         if (new_plan) {
1587                 old_plan = device->rs_plan_s;
1588                 rcu_assign_pointer(device->rs_plan_s, new_plan);
1589         }
1590
1591         mutex_unlock(&device->resource->conf_update);
1592
1593         if (new_disk_conf->al_updates)
1594                 device->ldev->md.flags &= ~MDF_AL_DISABLED;
1595         else
1596                 device->ldev->md.flags |= MDF_AL_DISABLED;
1597
1598         if (new_disk_conf->md_flushes)
1599                 clear_bit(MD_NO_FUA, &device->flags);
1600         else
1601                 set_bit(MD_NO_FUA, &device->flags);
1602
1603         if (write_ordering_changed(old_disk_conf, new_disk_conf))
1604                 drbd_bump_write_ordering(device->resource, NULL, WO_BDEV_FLUSH);
1605
1606         if (old_disk_conf->discard_zeroes_if_aligned !=
1607             new_disk_conf->discard_zeroes_if_aligned)
1608                 drbd_reconsider_queue_parameters(device, device->ldev, NULL);
1609
1610         drbd_md_sync(device);
1611
1612         if (device->state.conn >= C_CONNECTED) {
1613                 struct drbd_peer_device *peer_device;
1614
1615                 for_each_peer_device(peer_device, device)
1616                         drbd_send_sync_param(peer_device);
1617         }
1618
1619         kvfree_rcu_mightsleep(old_disk_conf);
1620         kfree(old_plan);
1621         mod_timer(&device->request_timer, jiffies + HZ);
1622         goto success;
1623
1624 fail_unlock:
1625         mutex_unlock(&device->resource->conf_update);
1626  fail:
1627         kfree(new_disk_conf);
1628         kfree(new_plan);
1629 success:
1630         put_ldev(device);
1631  out:
1632         mutex_unlock(&adm_ctx.resource->adm_mutex);
1633  finish:
1634         drbd_adm_finish(&adm_ctx, info, retcode);
1635         return 0;
1636 }
1637
1638 static struct block_device *open_backing_dev(struct drbd_device *device,
1639                 const char *bdev_path, void *claim_ptr, bool do_bd_link)
1640 {
1641         struct block_device *bdev;
1642         int err = 0;
1643
1644         bdev = blkdev_get_by_path(bdev_path, BLK_OPEN_READ | BLK_OPEN_WRITE,
1645                                   claim_ptr, NULL);
1646         if (IS_ERR(bdev)) {
1647                 drbd_err(device, "open(\"%s\") failed with %ld\n",
1648                                 bdev_path, PTR_ERR(bdev));
1649                 return bdev;
1650         }
1651
1652         if (!do_bd_link)
1653                 return bdev;
1654
1655         err = bd_link_disk_holder(bdev, device->vdisk);
1656         if (err) {
1657                 blkdev_put(bdev, claim_ptr);
1658                 drbd_err(device, "bd_link_disk_holder(\"%s\", ...) failed with %d\n",
1659                                 bdev_path, err);
1660                 bdev = ERR_PTR(err);
1661         }
1662         return bdev;
1663 }
1664
1665 static int open_backing_devices(struct drbd_device *device,
1666                 struct disk_conf *new_disk_conf,
1667                 struct drbd_backing_dev *nbc)
1668 {
1669         struct block_device *bdev;
1670
1671         bdev = open_backing_dev(device, new_disk_conf->backing_dev, device, true);
1672         if (IS_ERR(bdev))
1673                 return ERR_OPEN_DISK;
1674         nbc->backing_bdev = bdev;
1675
1676         /*
1677          * meta_dev_idx >= 0: external fixed size, possibly multiple
1678          * drbd sharing one meta device.  TODO in that case, paranoia
1679          * check that [md_bdev, meta_dev_idx] is not yet used by some
1680          * other drbd minor!  (if you use drbd.conf + drbdadm, that
1681          * should check it for you already; but if you don't, or
1682          * someone fooled it, we need to double check here)
1683          */
1684         bdev = open_backing_dev(device, new_disk_conf->meta_dev,
1685                 /* claim ptr: device, if claimed exclusively; shared drbd_m_holder,
1686                  * if potentially shared with other drbd minors */
1687                         (new_disk_conf->meta_dev_idx < 0) ? (void*)device : (void*)drbd_m_holder,
1688                 /* avoid double bd_claim_by_disk() for the same (source,target) tuple,
1689                  * as would happen with internal metadata. */
1690                         (new_disk_conf->meta_dev_idx != DRBD_MD_INDEX_FLEX_INT &&
1691                          new_disk_conf->meta_dev_idx != DRBD_MD_INDEX_INTERNAL));
1692         if (IS_ERR(bdev))
1693                 return ERR_OPEN_MD_DISK;
1694         nbc->md_bdev = bdev;
1695         return NO_ERROR;
1696 }
1697
1698 static void close_backing_dev(struct drbd_device *device, struct block_device *bdev,
1699                 void *claim_ptr, bool do_bd_unlink)
1700 {
1701         if (!bdev)
1702                 return;
1703         if (do_bd_unlink)
1704                 bd_unlink_disk_holder(bdev, device->vdisk);
1705         blkdev_put(bdev, claim_ptr);
1706 }
1707
1708 void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *ldev)
1709 {
1710         if (ldev == NULL)
1711                 return;
1712
1713         close_backing_dev(device, ldev->md_bdev,
1714                           ldev->md.meta_dev_idx < 0 ?
1715                                 (void *)device : (void *)drbd_m_holder,
1716                           ldev->md_bdev != ldev->backing_bdev);
1717         close_backing_dev(device, ldev->backing_bdev, device, true);
1718
1719         kfree(ldev->disk_conf);
1720         kfree(ldev);
1721 }
1722
1723 int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info)
1724 {
1725         struct drbd_config_context adm_ctx;
1726         struct drbd_device *device;
1727         struct drbd_peer_device *peer_device;
1728         struct drbd_connection *connection;
1729         int err;
1730         enum drbd_ret_code retcode;
1731         enum determine_dev_size dd;
1732         sector_t max_possible_sectors;
1733         sector_t min_md_device_sectors;
1734         struct drbd_backing_dev *nbc = NULL; /* new_backing_conf */
1735         struct disk_conf *new_disk_conf = NULL;
1736         struct lru_cache *resync_lru = NULL;
1737         struct fifo_buffer *new_plan = NULL;
1738         union drbd_state ns, os;
1739         enum drbd_state_rv rv;
1740         struct net_conf *nc;
1741
1742         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
1743         if (!adm_ctx.reply_skb)
1744                 return retcode;
1745         if (retcode != NO_ERROR)
1746                 goto finish;
1747
1748         device = adm_ctx.device;
1749         mutex_lock(&adm_ctx.resource->adm_mutex);
1750         peer_device = first_peer_device(device);
1751         connection = peer_device->connection;
1752         conn_reconfig_start(connection);
1753
1754         /* if you want to reconfigure, please tear down first */
1755         if (device->state.disk > D_DISKLESS) {
1756                 retcode = ERR_DISK_CONFIGURED;
1757                 goto fail;
1758         }
1759         /* It may just now have detached because of IO error.  Make sure
1760          * drbd_ldev_destroy is done already, we may end up here very fast,
1761          * e.g. if someone calls attach from the on-io-error handler,
1762          * to realize a "hot spare" feature (not that I'd recommend that) */
1763         wait_event(device->misc_wait, !test_bit(GOING_DISKLESS, &device->flags));
1764
1765         /* make sure there is no leftover from previous force-detach attempts */
1766         clear_bit(FORCE_DETACH, &device->flags);
1767         clear_bit(WAS_IO_ERROR, &device->flags);
1768         clear_bit(WAS_READ_ERROR, &device->flags);
1769
1770         /* and no leftover from previously aborted resync or verify, either */
1771         device->rs_total = 0;
1772         device->rs_failed = 0;
1773         atomic_set(&device->rs_pending_cnt, 0);
1774
1775         /* allocation not in the IO path, drbdsetup context */
1776         nbc = kzalloc(sizeof(struct drbd_backing_dev), GFP_KERNEL);
1777         if (!nbc) {
1778                 retcode = ERR_NOMEM;
1779                 goto fail;
1780         }
1781         spin_lock_init(&nbc->md.uuid_lock);
1782
1783         new_disk_conf = kzalloc(sizeof(struct disk_conf), GFP_KERNEL);
1784         if (!new_disk_conf) {
1785                 retcode = ERR_NOMEM;
1786                 goto fail;
1787         }
1788         nbc->disk_conf = new_disk_conf;
1789
1790         set_disk_conf_defaults(new_disk_conf);
1791         err = disk_conf_from_attrs(new_disk_conf, info);
1792         if (err) {
1793                 retcode = ERR_MANDATORY_TAG;
1794                 drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
1795                 goto fail;
1796         }
1797
1798         if (new_disk_conf->c_plan_ahead > DRBD_C_PLAN_AHEAD_MAX)
1799                 new_disk_conf->c_plan_ahead = DRBD_C_PLAN_AHEAD_MAX;
1800
1801         new_plan = fifo_alloc((new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ);
1802         if (!new_plan) {
1803                 retcode = ERR_NOMEM;
1804                 goto fail;
1805         }
1806
1807         if (new_disk_conf->meta_dev_idx < DRBD_MD_INDEX_FLEX_INT) {
1808                 retcode = ERR_MD_IDX_INVALID;
1809                 goto fail;
1810         }
1811
1812         rcu_read_lock();
1813         nc = rcu_dereference(connection->net_conf);
1814         if (nc) {
1815                 if (new_disk_conf->fencing == FP_STONITH && nc->wire_protocol == DRBD_PROT_A) {
1816                         rcu_read_unlock();
1817                         retcode = ERR_STONITH_AND_PROT_A;
1818                         goto fail;
1819                 }
1820         }
1821         rcu_read_unlock();
1822
1823         retcode = open_backing_devices(device, new_disk_conf, nbc);
1824         if (retcode != NO_ERROR)
1825                 goto fail;
1826
1827         if ((nbc->backing_bdev == nbc->md_bdev) !=
1828             (new_disk_conf->meta_dev_idx == DRBD_MD_INDEX_INTERNAL ||
1829              new_disk_conf->meta_dev_idx == DRBD_MD_INDEX_FLEX_INT)) {
1830                 retcode = ERR_MD_IDX_INVALID;
1831                 goto fail;
1832         }
1833
1834         resync_lru = lc_create("resync", drbd_bm_ext_cache,
1835                         1, 61, sizeof(struct bm_extent),
1836                         offsetof(struct bm_extent, lce));
1837         if (!resync_lru) {
1838                 retcode = ERR_NOMEM;
1839                 goto fail;
1840         }
1841
1842         /* Read our meta data super block early.
1843          * This also sets other on-disk offsets. */
1844         retcode = drbd_md_read(device, nbc);
1845         if (retcode != NO_ERROR)
1846                 goto fail;
1847
1848         sanitize_disk_conf(device, new_disk_conf, nbc);
1849
1850         if (drbd_get_max_capacity(nbc) < new_disk_conf->disk_size) {
1851                 drbd_err(device, "max capacity %llu smaller than disk size %llu\n",
1852                         (unsigned long long) drbd_get_max_capacity(nbc),
1853                         (unsigned long long) new_disk_conf->disk_size);
1854                 retcode = ERR_DISK_TOO_SMALL;
1855                 goto fail;
1856         }
1857
1858         if (new_disk_conf->meta_dev_idx < 0) {
1859                 max_possible_sectors = DRBD_MAX_SECTORS_FLEX;
1860                 /* at least one MB, otherwise it does not make sense */
1861                 min_md_device_sectors = (2<<10);
1862         } else {
1863                 max_possible_sectors = DRBD_MAX_SECTORS;
1864                 min_md_device_sectors = MD_128MB_SECT * (new_disk_conf->meta_dev_idx + 1);
1865         }
1866
1867         if (drbd_get_capacity(nbc->md_bdev) < min_md_device_sectors) {
1868                 retcode = ERR_MD_DISK_TOO_SMALL;
1869                 drbd_warn(device, "refusing attach: md-device too small, "
1870                      "at least %llu sectors needed for this meta-disk type\n",
1871                      (unsigned long long) min_md_device_sectors);
1872                 goto fail;
1873         }
1874
1875         /* Make sure the new disk is big enough
1876          * (we may currently be R_PRIMARY with no local disk...) */
1877         if (drbd_get_max_capacity(nbc) < get_capacity(device->vdisk)) {
1878                 retcode = ERR_DISK_TOO_SMALL;
1879                 goto fail;
1880         }
1881
1882         nbc->known_size = drbd_get_capacity(nbc->backing_bdev);
1883
1884         if (nbc->known_size > max_possible_sectors) {
1885                 drbd_warn(device, "==> truncating very big lower level device "
1886                         "to currently maximum possible %llu sectors <==\n",
1887                         (unsigned long long) max_possible_sectors);
1888                 if (new_disk_conf->meta_dev_idx >= 0)
1889                         drbd_warn(device, "==>> using internal or flexible "
1890                                       "meta data may help <<==\n");
1891         }
1892
1893         drbd_suspend_io(device);
1894         /* also wait for the last barrier ack. */
1895         /* FIXME see also https://daiquiri.linbit/cgi-bin/bugzilla/show_bug.cgi?id=171
1896          * We need a way to either ignore barrier acks for barriers sent before a device
1897          * was attached, or a way to wait for all pending barrier acks to come in.
1898          * As barriers are counted per resource,
1899          * we'd need to suspend io on all devices of a resource.
1900          */
1901         wait_event(device->misc_wait, !atomic_read(&device->ap_pending_cnt) || drbd_suspended(device));
1902         /* and for any other previously queued work */
1903         drbd_flush_workqueue(&connection->sender_work);
1904
1905         rv = _drbd_request_state(device, NS(disk, D_ATTACHING), CS_VERBOSE);
1906         retcode = (enum drbd_ret_code)rv;
1907         drbd_resume_io(device);
1908         if (rv < SS_SUCCESS)
1909                 goto fail;
1910
1911         if (!get_ldev_if_state(device, D_ATTACHING))
1912                 goto force_diskless;
1913
1914         if (!device->bitmap) {
1915                 if (drbd_bm_init(device)) {
1916                         retcode = ERR_NOMEM;
1917                         goto force_diskless_dec;
1918                 }
1919         }
1920
1921         if (device->state.pdsk != D_UP_TO_DATE && device->ed_uuid &&
1922             (device->state.role == R_PRIMARY || device->state.peer == R_PRIMARY) &&
1923             (device->ed_uuid & ~((u64)1)) != (nbc->md.uuid[UI_CURRENT] & ~((u64)1))) {
1924                 drbd_err(device, "Can only attach to data with current UUID=%016llX\n",
1925                     (unsigned long long)device->ed_uuid);
1926                 retcode = ERR_DATA_NOT_CURRENT;
1927                 goto force_diskless_dec;
1928         }
1929
1930         /* Since we are diskless, fix the activity log first... */
1931         if (drbd_check_al_size(device, new_disk_conf)) {
1932                 retcode = ERR_NOMEM;
1933                 goto force_diskless_dec;
1934         }
1935
1936         /* Prevent shrinking of consistent devices ! */
1937         {
1938         unsigned long long nsz = drbd_new_dev_size(device, nbc, nbc->disk_conf->disk_size, 0);
1939         unsigned long long eff = nbc->md.la_size_sect;
1940         if (drbd_md_test_flag(nbc, MDF_CONSISTENT) && nsz < eff) {
1941                 if (nsz == nbc->disk_conf->disk_size) {
1942                         drbd_warn(device, "truncating a consistent device during attach (%llu < %llu)\n", nsz, eff);
1943                 } else {
1944                         drbd_warn(device, "refusing to truncate a consistent device (%llu < %llu)\n", nsz, eff);
1945                         drbd_msg_sprintf_info(adm_ctx.reply_skb,
1946                                 "To-be-attached device has last effective > current size, and is consistent\n"
1947                                 "(%llu > %llu sectors). Refusing to attach.", eff, nsz);
1948                         retcode = ERR_IMPLICIT_SHRINK;
1949                         goto force_diskless_dec;
1950                 }
1951         }
1952         }
1953
1954         lock_all_resources();
1955         retcode = drbd_resync_after_valid(device, new_disk_conf->resync_after);
1956         if (retcode != NO_ERROR) {
1957                 unlock_all_resources();
1958                 goto force_diskless_dec;
1959         }
1960
1961         /* Reset the "barriers don't work" bits here, then force meta data to
1962          * be written, to ensure we determine if barriers are supported. */
1963         if (new_disk_conf->md_flushes)
1964                 clear_bit(MD_NO_FUA, &device->flags);
1965         else
1966                 set_bit(MD_NO_FUA, &device->flags);
1967
1968         /* Point of no return reached.
1969          * Devices and memory are no longer released by error cleanup below.
1970          * now device takes over responsibility, and the state engine should
1971          * clean it up somewhere.  */
1972         D_ASSERT(device, device->ldev == NULL);
1973         device->ldev = nbc;
1974         device->resync = resync_lru;
1975         device->rs_plan_s = new_plan;
1976         nbc = NULL;
1977         resync_lru = NULL;
1978         new_disk_conf = NULL;
1979         new_plan = NULL;
1980
1981         drbd_resync_after_changed(device);
1982         drbd_bump_write_ordering(device->resource, device->ldev, WO_BDEV_FLUSH);
1983         unlock_all_resources();
1984
1985         if (drbd_md_test_flag(device->ldev, MDF_CRASHED_PRIMARY))
1986                 set_bit(CRASHED_PRIMARY, &device->flags);
1987         else
1988                 clear_bit(CRASHED_PRIMARY, &device->flags);
1989
1990         if (drbd_md_test_flag(device->ldev, MDF_PRIMARY_IND) &&
1991             !(device->state.role == R_PRIMARY && device->resource->susp_nod))
1992                 set_bit(CRASHED_PRIMARY, &device->flags);
1993
1994         device->send_cnt = 0;
1995         device->recv_cnt = 0;
1996         device->read_cnt = 0;
1997         device->writ_cnt = 0;
1998
1999         drbd_reconsider_queue_parameters(device, device->ldev, NULL);
2000
2001         /* If I am currently not R_PRIMARY,
2002          * but meta data primary indicator is set,
2003          * I just now recover from a hard crash,
2004          * and have been R_PRIMARY before that crash.
2005          *
2006          * Now, if I had no connection before that crash
2007          * (have been degraded R_PRIMARY), chances are that
2008          * I won't find my peer now either.
2009          *
2010          * In that case, and _only_ in that case,
2011          * we use the degr-wfc-timeout instead of the default,
2012          * so we can automatically recover from a crash of a
2013          * degraded but active "cluster" after a certain timeout.
2014          */
2015         clear_bit(USE_DEGR_WFC_T, &device->flags);
2016         if (device->state.role != R_PRIMARY &&
2017              drbd_md_test_flag(device->ldev, MDF_PRIMARY_IND) &&
2018             !drbd_md_test_flag(device->ldev, MDF_CONNECTED_IND))
2019                 set_bit(USE_DEGR_WFC_T, &device->flags);
2020
2021         dd = drbd_determine_dev_size(device, 0, NULL);
2022         if (dd <= DS_ERROR) {
2023                 retcode = ERR_NOMEM_BITMAP;
2024                 goto force_diskless_dec;
2025         } else if (dd == DS_GREW)
2026                 set_bit(RESYNC_AFTER_NEG, &device->flags);
2027
2028         if (drbd_md_test_flag(device->ldev, MDF_FULL_SYNC) ||
2029             (test_bit(CRASHED_PRIMARY, &device->flags) &&
2030              drbd_md_test_flag(device->ldev, MDF_AL_DISABLED))) {
2031                 drbd_info(device, "Assuming that all blocks are out of sync "
2032                      "(aka FullSync)\n");
2033                 if (drbd_bitmap_io(device, &drbd_bmio_set_n_write,
2034                         "set_n_write from attaching", BM_LOCKED_MASK,
2035                         NULL)) {
2036                         retcode = ERR_IO_MD_DISK;
2037                         goto force_diskless_dec;
2038                 }
2039         } else {
2040                 if (drbd_bitmap_io(device, &drbd_bm_read,
2041                         "read from attaching", BM_LOCKED_MASK,
2042                         NULL)) {
2043                         retcode = ERR_IO_MD_DISK;
2044                         goto force_diskless_dec;
2045                 }
2046         }
2047
2048         if (_drbd_bm_total_weight(device) == drbd_bm_bits(device))
2049                 drbd_suspend_al(device); /* IO is still suspended here... */
2050
2051         spin_lock_irq(&device->resource->req_lock);
2052         os = drbd_read_state(device);
2053         ns = os;
2054         /* If MDF_CONSISTENT is not set go into inconsistent state,
2055            otherwise investigate MDF_WasUpToDate...
2056            If MDF_WAS_UP_TO_DATE is not set go into D_OUTDATED disk state,
2057            otherwise into D_CONSISTENT state.
2058         */
2059         if (drbd_md_test_flag(device->ldev, MDF_CONSISTENT)) {
2060                 if (drbd_md_test_flag(device->ldev, MDF_WAS_UP_TO_DATE))
2061                         ns.disk = D_CONSISTENT;
2062                 else
2063                         ns.disk = D_OUTDATED;
2064         } else {
2065                 ns.disk = D_INCONSISTENT;
2066         }
2067
2068         if (drbd_md_test_flag(device->ldev, MDF_PEER_OUT_DATED))
2069                 ns.pdsk = D_OUTDATED;
2070
2071         rcu_read_lock();
2072         if (ns.disk == D_CONSISTENT &&
2073             (ns.pdsk == D_OUTDATED || rcu_dereference(device->ldev->disk_conf)->fencing == FP_DONT_CARE))
2074                 ns.disk = D_UP_TO_DATE;
2075
2076         /* All tests on MDF_PRIMARY_IND, MDF_CONNECTED_IND,
2077            MDF_CONSISTENT and MDF_WAS_UP_TO_DATE must happen before
2078            this point, because drbd_request_state() modifies these
2079            flags. */
2080
2081         if (rcu_dereference(device->ldev->disk_conf)->al_updates)
2082                 device->ldev->md.flags &= ~MDF_AL_DISABLED;
2083         else
2084                 device->ldev->md.flags |= MDF_AL_DISABLED;
2085
2086         rcu_read_unlock();
2087
2088         /* In case we are C_CONNECTED postpone any decision on the new disk
2089            state after the negotiation phase. */
2090         if (device->state.conn == C_CONNECTED) {
2091                 device->new_state_tmp.i = ns.i;
2092                 ns.i = os.i;
2093                 ns.disk = D_NEGOTIATING;
2094
2095                 /* We expect to receive up-to-date UUIDs soon.
2096                    To avoid a race in receive_state, free p_uuid while
2097                    holding req_lock. I.e. atomic with the state change */
2098                 kfree(device->p_uuid);
2099                 device->p_uuid = NULL;
2100         }
2101
2102         rv = _drbd_set_state(device, ns, CS_VERBOSE, NULL);
2103         spin_unlock_irq(&device->resource->req_lock);
2104
2105         if (rv < SS_SUCCESS)
2106                 goto force_diskless_dec;
2107
2108         mod_timer(&device->request_timer, jiffies + HZ);
2109
2110         if (device->state.role == R_PRIMARY)
2111                 device->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
2112         else
2113                 device->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
2114
2115         drbd_md_mark_dirty(device);
2116         drbd_md_sync(device);
2117
2118         kobject_uevent(&disk_to_dev(device->vdisk)->kobj, KOBJ_CHANGE);
2119         put_ldev(device);
2120         conn_reconfig_done(connection);
2121         mutex_unlock(&adm_ctx.resource->adm_mutex);
2122         drbd_adm_finish(&adm_ctx, info, retcode);
2123         return 0;
2124
2125  force_diskless_dec:
2126         put_ldev(device);
2127  force_diskless:
2128         drbd_force_state(device, NS(disk, D_DISKLESS));
2129         drbd_md_sync(device);
2130  fail:
2131         conn_reconfig_done(connection);
2132         if (nbc) {
2133                 close_backing_dev(device, nbc->md_bdev,
2134                           nbc->disk_conf->meta_dev_idx < 0 ?
2135                                 (void *)device : (void *)drbd_m_holder,
2136                           nbc->md_bdev != nbc->backing_bdev);
2137                 close_backing_dev(device, nbc->backing_bdev, device, true);
2138                 kfree(nbc);
2139         }
2140         kfree(new_disk_conf);
2141         lc_destroy(resync_lru);
2142         kfree(new_plan);
2143         mutex_unlock(&adm_ctx.resource->adm_mutex);
2144  finish:
2145         drbd_adm_finish(&adm_ctx, info, retcode);
2146         return 0;
2147 }
2148
2149 static int adm_detach(struct drbd_device *device, int force)
2150 {
2151         if (force) {
2152                 set_bit(FORCE_DETACH, &device->flags);
2153                 drbd_force_state(device, NS(disk, D_FAILED));
2154                 return SS_SUCCESS;
2155         }
2156
2157         return drbd_request_detach_interruptible(device);
2158 }
2159
2160 /* Detaching the disk is a process in multiple stages.  First we need to lock
2161  * out application IO, in-flight IO, IO stuck in drbd_al_begin_io.
2162  * Then we transition to D_DISKLESS, and wait for put_ldev() to return all
2163  * internal references as well.
2164  * Only then we have finally detached. */
2165 int drbd_adm_detach(struct sk_buff *skb, struct genl_info *info)
2166 {
2167         struct drbd_config_context adm_ctx;
2168         enum drbd_ret_code retcode;
2169         struct detach_parms parms = { };
2170         int err;
2171
2172         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
2173         if (!adm_ctx.reply_skb)
2174                 return retcode;
2175         if (retcode != NO_ERROR)
2176                 goto out;
2177
2178         if (info->attrs[DRBD_NLA_DETACH_PARMS]) {
2179                 err = detach_parms_from_attrs(&parms, info);
2180                 if (err) {
2181                         retcode = ERR_MANDATORY_TAG;
2182                         drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
2183                         goto out;
2184                 }
2185         }
2186
2187         mutex_lock(&adm_ctx.resource->adm_mutex);
2188         retcode = adm_detach(adm_ctx.device, parms.force_detach);
2189         mutex_unlock(&adm_ctx.resource->adm_mutex);
2190 out:
2191         drbd_adm_finish(&adm_ctx, info, retcode);
2192         return 0;
2193 }
2194
2195 static bool conn_resync_running(struct drbd_connection *connection)
2196 {
2197         struct drbd_peer_device *peer_device;
2198         bool rv = false;
2199         int vnr;
2200
2201         rcu_read_lock();
2202         idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
2203                 struct drbd_device *device = peer_device->device;
2204                 if (device->state.conn == C_SYNC_SOURCE ||
2205                     device->state.conn == C_SYNC_TARGET ||
2206                     device->state.conn == C_PAUSED_SYNC_S ||
2207                     device->state.conn == C_PAUSED_SYNC_T) {
2208                         rv = true;
2209                         break;
2210                 }
2211         }
2212         rcu_read_unlock();
2213
2214         return rv;
2215 }
2216
2217 static bool conn_ov_running(struct drbd_connection *connection)
2218 {
2219         struct drbd_peer_device *peer_device;
2220         bool rv = false;
2221         int vnr;
2222
2223         rcu_read_lock();
2224         idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
2225                 struct drbd_device *device = peer_device->device;
2226                 if (device->state.conn == C_VERIFY_S ||
2227                     device->state.conn == C_VERIFY_T) {
2228                         rv = true;
2229                         break;
2230                 }
2231         }
2232         rcu_read_unlock();
2233
2234         return rv;
2235 }
2236
2237 static enum drbd_ret_code
2238 _check_net_options(struct drbd_connection *connection, struct net_conf *old_net_conf, struct net_conf *new_net_conf)
2239 {
2240         struct drbd_peer_device *peer_device;
2241         int i;
2242
2243         if (old_net_conf && connection->cstate == C_WF_REPORT_PARAMS && connection->agreed_pro_version < 100) {
2244                 if (new_net_conf->wire_protocol != old_net_conf->wire_protocol)
2245                         return ERR_NEED_APV_100;
2246
2247                 if (new_net_conf->two_primaries != old_net_conf->two_primaries)
2248                         return ERR_NEED_APV_100;
2249
2250                 if (strcmp(new_net_conf->integrity_alg, old_net_conf->integrity_alg))
2251                         return ERR_NEED_APV_100;
2252         }
2253
2254         if (!new_net_conf->two_primaries &&
2255             conn_highest_role(connection) == R_PRIMARY &&
2256             conn_highest_peer(connection) == R_PRIMARY)
2257                 return ERR_NEED_ALLOW_TWO_PRI;
2258
2259         if (new_net_conf->two_primaries &&
2260             (new_net_conf->wire_protocol != DRBD_PROT_C))
2261                 return ERR_NOT_PROTO_C;
2262
2263         idr_for_each_entry(&connection->peer_devices, peer_device, i) {
2264                 struct drbd_device *device = peer_device->device;
2265                 if (get_ldev(device)) {
2266                         enum drbd_fencing_p fp = rcu_dereference(device->ldev->disk_conf)->fencing;
2267                         put_ldev(device);
2268                         if (new_net_conf->wire_protocol == DRBD_PROT_A && fp == FP_STONITH)
2269                                 return ERR_STONITH_AND_PROT_A;
2270                 }
2271                 if (device->state.role == R_PRIMARY && new_net_conf->discard_my_data)
2272                         return ERR_DISCARD_IMPOSSIBLE;
2273         }
2274
2275         if (new_net_conf->on_congestion != OC_BLOCK && new_net_conf->wire_protocol != DRBD_PROT_A)
2276                 return ERR_CONG_NOT_PROTO_A;
2277
2278         return NO_ERROR;
2279 }
2280
2281 static enum drbd_ret_code
2282 check_net_options(struct drbd_connection *connection, struct net_conf *new_net_conf)
2283 {
2284         enum drbd_ret_code rv;
2285         struct drbd_peer_device *peer_device;
2286         int i;
2287
2288         rcu_read_lock();
2289         rv = _check_net_options(connection, rcu_dereference(connection->net_conf), new_net_conf);
2290         rcu_read_unlock();
2291
2292         /* connection->peer_devices protected by genl_lock() here */
2293         idr_for_each_entry(&connection->peer_devices, peer_device, i) {
2294                 struct drbd_device *device = peer_device->device;
2295                 if (!device->bitmap) {
2296                         if (drbd_bm_init(device))
2297                                 return ERR_NOMEM;
2298                 }
2299         }
2300
2301         return rv;
2302 }
2303
2304 struct crypto {
2305         struct crypto_shash *verify_tfm;
2306         struct crypto_shash *csums_tfm;
2307         struct crypto_shash *cram_hmac_tfm;
2308         struct crypto_shash *integrity_tfm;
2309 };
2310
2311 static int
2312 alloc_shash(struct crypto_shash **tfm, char *tfm_name, int err_alg)
2313 {
2314         if (!tfm_name[0])
2315                 return NO_ERROR;
2316
2317         *tfm = crypto_alloc_shash(tfm_name, 0, 0);
2318         if (IS_ERR(*tfm)) {
2319                 *tfm = NULL;
2320                 return err_alg;
2321         }
2322
2323         return NO_ERROR;
2324 }
2325
2326 static enum drbd_ret_code
2327 alloc_crypto(struct crypto *crypto, struct net_conf *new_net_conf)
2328 {
2329         char hmac_name[CRYPTO_MAX_ALG_NAME];
2330         enum drbd_ret_code rv;
2331
2332         rv = alloc_shash(&crypto->csums_tfm, new_net_conf->csums_alg,
2333                          ERR_CSUMS_ALG);
2334         if (rv != NO_ERROR)
2335                 return rv;
2336         rv = alloc_shash(&crypto->verify_tfm, new_net_conf->verify_alg,
2337                          ERR_VERIFY_ALG);
2338         if (rv != NO_ERROR)
2339                 return rv;
2340         rv = alloc_shash(&crypto->integrity_tfm, new_net_conf->integrity_alg,
2341                          ERR_INTEGRITY_ALG);
2342         if (rv != NO_ERROR)
2343                 return rv;
2344         if (new_net_conf->cram_hmac_alg[0] != 0) {
2345                 snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",
2346                          new_net_conf->cram_hmac_alg);
2347
2348                 rv = alloc_shash(&crypto->cram_hmac_tfm, hmac_name,
2349                                  ERR_AUTH_ALG);
2350         }
2351
2352         return rv;
2353 }
2354
2355 static void free_crypto(struct crypto *crypto)
2356 {
2357         crypto_free_shash(crypto->cram_hmac_tfm);
2358         crypto_free_shash(crypto->integrity_tfm);
2359         crypto_free_shash(crypto->csums_tfm);
2360         crypto_free_shash(crypto->verify_tfm);
2361 }
2362
2363 int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
2364 {
2365         struct drbd_config_context adm_ctx;
2366         enum drbd_ret_code retcode;
2367         struct drbd_connection *connection;
2368         struct net_conf *old_net_conf, *new_net_conf = NULL;
2369         int err;
2370         int ovr; /* online verify running */
2371         int rsr; /* re-sync running */
2372         struct crypto crypto = { };
2373
2374         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_CONNECTION);
2375         if (!adm_ctx.reply_skb)
2376                 return retcode;
2377         if (retcode != NO_ERROR)
2378                 goto finish;
2379
2380         connection = adm_ctx.connection;
2381         mutex_lock(&adm_ctx.resource->adm_mutex);
2382
2383         new_net_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
2384         if (!new_net_conf) {
2385                 retcode = ERR_NOMEM;
2386                 goto out;
2387         }
2388
2389         conn_reconfig_start(connection);
2390
2391         mutex_lock(&connection->data.mutex);
2392         mutex_lock(&connection->resource->conf_update);
2393         old_net_conf = connection->net_conf;
2394
2395         if (!old_net_conf) {
2396                 drbd_msg_put_info(adm_ctx.reply_skb, "net conf missing, try connect");
2397                 retcode = ERR_INVALID_REQUEST;
2398                 goto fail;
2399         }
2400
2401         *new_net_conf = *old_net_conf;
2402         if (should_set_defaults(info))
2403                 set_net_conf_defaults(new_net_conf);
2404
2405         err = net_conf_from_attrs_for_change(new_net_conf, info);
2406         if (err && err != -ENOMSG) {
2407                 retcode = ERR_MANDATORY_TAG;
2408                 drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
2409                 goto fail;
2410         }
2411
2412         retcode = check_net_options(connection, new_net_conf);
2413         if (retcode != NO_ERROR)
2414                 goto fail;
2415
2416         /* re-sync running */
2417         rsr = conn_resync_running(connection);
2418         if (rsr && strcmp(new_net_conf->csums_alg, old_net_conf->csums_alg)) {
2419                 retcode = ERR_CSUMS_RESYNC_RUNNING;
2420                 goto fail;
2421         }
2422
2423         /* online verify running */
2424         ovr = conn_ov_running(connection);
2425         if (ovr && strcmp(new_net_conf->verify_alg, old_net_conf->verify_alg)) {
2426                 retcode = ERR_VERIFY_RUNNING;
2427                 goto fail;
2428         }
2429
2430         retcode = alloc_crypto(&crypto, new_net_conf);
2431         if (retcode != NO_ERROR)
2432                 goto fail;
2433
2434         rcu_assign_pointer(connection->net_conf, new_net_conf);
2435
2436         if (!rsr) {
2437                 crypto_free_shash(connection->csums_tfm);
2438                 connection->csums_tfm = crypto.csums_tfm;
2439                 crypto.csums_tfm = NULL;
2440         }
2441         if (!ovr) {
2442                 crypto_free_shash(connection->verify_tfm);
2443                 connection->verify_tfm = crypto.verify_tfm;
2444                 crypto.verify_tfm = NULL;
2445         }
2446
2447         crypto_free_shash(connection->integrity_tfm);
2448         connection->integrity_tfm = crypto.integrity_tfm;
2449         if (connection->cstate >= C_WF_REPORT_PARAMS && connection->agreed_pro_version >= 100)
2450                 /* Do this without trying to take connection->data.mutex again.  */
2451                 __drbd_send_protocol(connection, P_PROTOCOL_UPDATE);
2452
2453         crypto_free_shash(connection->cram_hmac_tfm);
2454         connection->cram_hmac_tfm = crypto.cram_hmac_tfm;
2455
2456         mutex_unlock(&connection->resource->conf_update);
2457         mutex_unlock(&connection->data.mutex);
2458         kvfree_rcu_mightsleep(old_net_conf);
2459
2460         if (connection->cstate >= C_WF_REPORT_PARAMS) {
2461                 struct drbd_peer_device *peer_device;
2462                 int vnr;
2463
2464                 idr_for_each_entry(&connection->peer_devices, peer_device, vnr)
2465                         drbd_send_sync_param(peer_device);
2466         }
2467
2468         goto done;
2469
2470  fail:
2471         mutex_unlock(&connection->resource->conf_update);
2472         mutex_unlock(&connection->data.mutex);
2473         free_crypto(&crypto);
2474         kfree(new_net_conf);
2475  done:
2476         conn_reconfig_done(connection);
2477  out:
2478         mutex_unlock(&adm_ctx.resource->adm_mutex);
2479  finish:
2480         drbd_adm_finish(&adm_ctx, info, retcode);
2481         return 0;
2482 }
2483
2484 static void connection_to_info(struct connection_info *info,
2485                                struct drbd_connection *connection)
2486 {
2487         info->conn_connection_state = connection->cstate;
2488         info->conn_role = conn_highest_peer(connection);
2489 }
2490
2491 static void peer_device_to_info(struct peer_device_info *info,
2492                                 struct drbd_peer_device *peer_device)
2493 {
2494         struct drbd_device *device = peer_device->device;
2495
2496         info->peer_repl_state =
2497                 max_t(enum drbd_conns, C_WF_REPORT_PARAMS, device->state.conn);
2498         info->peer_disk_state = device->state.pdsk;
2499         info->peer_resync_susp_user = device->state.user_isp;
2500         info->peer_resync_susp_peer = device->state.peer_isp;
2501         info->peer_resync_susp_dependency = device->state.aftr_isp;
2502 }
2503
2504 int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info)
2505 {
2506         struct connection_info connection_info;
2507         enum drbd_notification_type flags;
2508         unsigned int peer_devices = 0;
2509         struct drbd_config_context adm_ctx;
2510         struct drbd_peer_device *peer_device;
2511         struct net_conf *old_net_conf, *new_net_conf = NULL;
2512         struct crypto crypto = { };
2513         struct drbd_resource *resource;
2514         struct drbd_connection *connection;
2515         enum drbd_ret_code retcode;
2516         enum drbd_state_rv rv;
2517         int i;
2518         int err;
2519
2520         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_RESOURCE);
2521
2522         if (!adm_ctx.reply_skb)
2523                 return retcode;
2524         if (retcode != NO_ERROR)
2525                 goto out;
2526         if (!(adm_ctx.my_addr && adm_ctx.peer_addr)) {
2527                 drbd_msg_put_info(adm_ctx.reply_skb, "connection endpoint(s) missing");
2528                 retcode = ERR_INVALID_REQUEST;
2529                 goto out;
2530         }
2531
2532         /* No need for _rcu here. All reconfiguration is
2533          * strictly serialized on genl_lock(). We are protected against
2534          * concurrent reconfiguration/addition/deletion */
2535         for_each_resource(resource, &drbd_resources) {
2536                 for_each_connection(connection, resource) {
2537                         if (nla_len(adm_ctx.my_addr) == connection->my_addr_len &&
2538                             !memcmp(nla_data(adm_ctx.my_addr), &connection->my_addr,
2539                                     connection->my_addr_len)) {
2540                                 retcode = ERR_LOCAL_ADDR;
2541                                 goto out;
2542                         }
2543
2544                         if (nla_len(adm_ctx.peer_addr) == connection->peer_addr_len &&
2545                             !memcmp(nla_data(adm_ctx.peer_addr), &connection->peer_addr,
2546                                     connection->peer_addr_len)) {
2547                                 retcode = ERR_PEER_ADDR;
2548                                 goto out;
2549                         }
2550                 }
2551         }
2552
2553         mutex_lock(&adm_ctx.resource->adm_mutex);
2554         connection = first_connection(adm_ctx.resource);
2555         conn_reconfig_start(connection);
2556
2557         if (connection->cstate > C_STANDALONE) {
2558                 retcode = ERR_NET_CONFIGURED;
2559                 goto fail;
2560         }
2561
2562         /* allocation not in the IO path, drbdsetup / netlink process context */
2563         new_net_conf = kzalloc(sizeof(*new_net_conf), GFP_KERNEL);
2564         if (!new_net_conf) {
2565                 retcode = ERR_NOMEM;
2566                 goto fail;
2567         }
2568
2569         set_net_conf_defaults(new_net_conf);
2570
2571         err = net_conf_from_attrs(new_net_conf, info);
2572         if (err && err != -ENOMSG) {
2573                 retcode = ERR_MANDATORY_TAG;
2574                 drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
2575                 goto fail;
2576         }
2577
2578         retcode = check_net_options(connection, new_net_conf);
2579         if (retcode != NO_ERROR)
2580                 goto fail;
2581
2582         retcode = alloc_crypto(&crypto, new_net_conf);
2583         if (retcode != NO_ERROR)
2584                 goto fail;
2585
2586         ((char *)new_net_conf->shared_secret)[SHARED_SECRET_MAX-1] = 0;
2587
2588         drbd_flush_workqueue(&connection->sender_work);
2589
2590         mutex_lock(&adm_ctx.resource->conf_update);
2591         old_net_conf = connection->net_conf;
2592         if (old_net_conf) {
2593                 retcode = ERR_NET_CONFIGURED;
2594                 mutex_unlock(&adm_ctx.resource->conf_update);
2595                 goto fail;
2596         }
2597         rcu_assign_pointer(connection->net_conf, new_net_conf);
2598
2599         conn_free_crypto(connection);
2600         connection->cram_hmac_tfm = crypto.cram_hmac_tfm;
2601         connection->integrity_tfm = crypto.integrity_tfm;
2602         connection->csums_tfm = crypto.csums_tfm;
2603         connection->verify_tfm = crypto.verify_tfm;
2604
2605         connection->my_addr_len = nla_len(adm_ctx.my_addr);
2606         memcpy(&connection->my_addr, nla_data(adm_ctx.my_addr), connection->my_addr_len);
2607         connection->peer_addr_len = nla_len(adm_ctx.peer_addr);
2608         memcpy(&connection->peer_addr, nla_data(adm_ctx.peer_addr), connection->peer_addr_len);
2609
2610         idr_for_each_entry(&connection->peer_devices, peer_device, i) {
2611                 peer_devices++;
2612         }
2613
2614         connection_to_info(&connection_info, connection);
2615         flags = (peer_devices--) ? NOTIFY_CONTINUES : 0;
2616         mutex_lock(&notification_mutex);
2617         notify_connection_state(NULL, 0, connection, &connection_info, NOTIFY_CREATE | flags);
2618         idr_for_each_entry(&connection->peer_devices, peer_device, i) {
2619                 struct peer_device_info peer_device_info;
2620
2621                 peer_device_to_info(&peer_device_info, peer_device);
2622                 flags = (peer_devices--) ? NOTIFY_CONTINUES : 0;
2623                 notify_peer_device_state(NULL, 0, peer_device, &peer_device_info, NOTIFY_CREATE | flags);
2624         }
2625         mutex_unlock(&notification_mutex);
2626         mutex_unlock(&adm_ctx.resource->conf_update);
2627
2628         rcu_read_lock();
2629         idr_for_each_entry(&connection->peer_devices, peer_device, i) {
2630                 struct drbd_device *device = peer_device->device;
2631                 device->send_cnt = 0;
2632                 device->recv_cnt = 0;
2633         }
2634         rcu_read_unlock();
2635
2636         rv = conn_request_state(connection, NS(conn, C_UNCONNECTED), CS_VERBOSE);
2637
2638         conn_reconfig_done(connection);
2639         mutex_unlock(&adm_ctx.resource->adm_mutex);
2640         drbd_adm_finish(&adm_ctx, info, rv);
2641         return 0;
2642
2643 fail:
2644         free_crypto(&crypto);
2645         kfree(new_net_conf);
2646
2647         conn_reconfig_done(connection);
2648         mutex_unlock(&adm_ctx.resource->adm_mutex);
2649 out:
2650         drbd_adm_finish(&adm_ctx, info, retcode);
2651         return 0;
2652 }
2653
2654 static enum drbd_state_rv conn_try_disconnect(struct drbd_connection *connection, bool force)
2655 {
2656         enum drbd_conns cstate;
2657         enum drbd_state_rv rv;
2658
2659 repeat:
2660         rv = conn_request_state(connection, NS(conn, C_DISCONNECTING),
2661                         force ? CS_HARD : 0);
2662
2663         switch (rv) {
2664         case SS_NOTHING_TO_DO:
2665                 break;
2666         case SS_ALREADY_STANDALONE:
2667                 return SS_SUCCESS;
2668         case SS_PRIMARY_NOP:
2669                 /* Our state checking code wants to see the peer outdated. */
2670                 rv = conn_request_state(connection, NS2(conn, C_DISCONNECTING, pdsk, D_OUTDATED), 0);
2671
2672                 if (rv == SS_OUTDATE_WO_CONN) /* lost connection before graceful disconnect succeeded */
2673                         rv = conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_VERBOSE);
2674
2675                 break;
2676         case SS_CW_FAILED_BY_PEER:
2677                 spin_lock_irq(&connection->resource->req_lock);
2678                 cstate = connection->cstate;
2679                 spin_unlock_irq(&connection->resource->req_lock);
2680                 if (cstate <= C_WF_CONNECTION)
2681                         goto repeat;
2682                 /* The peer probably wants to see us outdated. */
2683                 rv = conn_request_state(connection, NS2(conn, C_DISCONNECTING,
2684                                                         disk, D_OUTDATED), 0);
2685                 if (rv == SS_IS_DISKLESS || rv == SS_LOWER_THAN_OUTDATED) {
2686                         rv = conn_request_state(connection, NS(conn, C_DISCONNECTING),
2687                                         CS_HARD);
2688                 }
2689                 break;
2690         default:;
2691                 /* no special handling necessary */
2692         }
2693
2694         if (rv >= SS_SUCCESS) {
2695                 enum drbd_state_rv rv2;
2696                 /* No one else can reconfigure the network while I am here.
2697                  * The state handling only uses drbd_thread_stop_nowait(),
2698                  * we want to really wait here until the receiver is no more.
2699                  */
2700                 drbd_thread_stop(&connection->receiver);
2701
2702                 /* Race breaker.  This additional state change request may be
2703                  * necessary, if this was a forced disconnect during a receiver
2704                  * restart.  We may have "killed" the receiver thread just
2705                  * after drbd_receiver() returned.  Typically, we should be
2706                  * C_STANDALONE already, now, and this becomes a no-op.
2707                  */
2708                 rv2 = conn_request_state(connection, NS(conn, C_STANDALONE),
2709                                 CS_VERBOSE | CS_HARD);
2710                 if (rv2 < SS_SUCCESS)
2711                         drbd_err(connection,
2712                                 "unexpected rv2=%d in conn_try_disconnect()\n",
2713                                 rv2);
2714                 /* Unlike in DRBD 9, the state engine has generated
2715                  * NOTIFY_DESTROY events before clearing connection->net_conf. */
2716         }
2717         return rv;
2718 }
2719
2720 int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info)
2721 {
2722         struct drbd_config_context adm_ctx;
2723         struct disconnect_parms parms;
2724         struct drbd_connection *connection;
2725         enum drbd_state_rv rv;
2726         enum drbd_ret_code retcode;
2727         int err;
2728
2729         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_CONNECTION);
2730         if (!adm_ctx.reply_skb)
2731                 return retcode;
2732         if (retcode != NO_ERROR)
2733                 goto fail;
2734
2735         connection = adm_ctx.connection;
2736         memset(&parms, 0, sizeof(parms));
2737         if (info->attrs[DRBD_NLA_DISCONNECT_PARMS]) {
2738                 err = disconnect_parms_from_attrs(&parms, info);
2739                 if (err) {
2740                         retcode = ERR_MANDATORY_TAG;
2741                         drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
2742                         goto fail;
2743                 }
2744         }
2745
2746         mutex_lock(&adm_ctx.resource->adm_mutex);
2747         rv = conn_try_disconnect(connection, parms.force_disconnect);
2748         mutex_unlock(&adm_ctx.resource->adm_mutex);
2749         if (rv < SS_SUCCESS) {
2750                 drbd_adm_finish(&adm_ctx, info, rv);
2751                 return 0;
2752         }
2753         retcode = NO_ERROR;
2754  fail:
2755         drbd_adm_finish(&adm_ctx, info, retcode);
2756         return 0;
2757 }
2758
2759 void resync_after_online_grow(struct drbd_device *device)
2760 {
2761         int iass; /* I am sync source */
2762
2763         drbd_info(device, "Resync of new storage after online grow\n");
2764         if (device->state.role != device->state.peer)
2765                 iass = (device->state.role == R_PRIMARY);
2766         else
2767                 iass = test_bit(RESOLVE_CONFLICTS, &first_peer_device(device)->connection->flags);
2768
2769         if (iass)
2770                 drbd_start_resync(device, C_SYNC_SOURCE);
2771         else
2772                 _drbd_request_state(device, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE + CS_SERIALIZE);
2773 }
2774
2775 int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
2776 {
2777         struct drbd_config_context adm_ctx;
2778         struct disk_conf *old_disk_conf, *new_disk_conf = NULL;
2779         struct resize_parms rs;
2780         struct drbd_device *device;
2781         enum drbd_ret_code retcode;
2782         enum determine_dev_size dd;
2783         bool change_al_layout = false;
2784         enum dds_flags ddsf;
2785         sector_t u_size;
2786         int err;
2787
2788         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
2789         if (!adm_ctx.reply_skb)
2790                 return retcode;
2791         if (retcode != NO_ERROR)
2792                 goto finish;
2793
2794         mutex_lock(&adm_ctx.resource->adm_mutex);
2795         device = adm_ctx.device;
2796         if (!get_ldev(device)) {
2797                 retcode = ERR_NO_DISK;
2798                 goto fail;
2799         }
2800
2801         memset(&rs, 0, sizeof(struct resize_parms));
2802         rs.al_stripes = device->ldev->md.al_stripes;
2803         rs.al_stripe_size = device->ldev->md.al_stripe_size_4k * 4;
2804         if (info->attrs[DRBD_NLA_RESIZE_PARMS]) {
2805                 err = resize_parms_from_attrs(&rs, info);
2806                 if (err) {
2807                         retcode = ERR_MANDATORY_TAG;
2808                         drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
2809                         goto fail_ldev;
2810                 }
2811         }
2812
2813         if (device->state.conn > C_CONNECTED) {
2814                 retcode = ERR_RESIZE_RESYNC;
2815                 goto fail_ldev;
2816         }
2817
2818         if (device->state.role == R_SECONDARY &&
2819             device->state.peer == R_SECONDARY) {
2820                 retcode = ERR_NO_PRIMARY;
2821                 goto fail_ldev;
2822         }
2823
2824         if (rs.no_resync && first_peer_device(device)->connection->agreed_pro_version < 93) {
2825                 retcode = ERR_NEED_APV_93;
2826                 goto fail_ldev;
2827         }
2828
2829         rcu_read_lock();
2830         u_size = rcu_dereference(device->ldev->disk_conf)->disk_size;
2831         rcu_read_unlock();
2832         if (u_size != (sector_t)rs.resize_size) {
2833                 new_disk_conf = kmalloc(sizeof(struct disk_conf), GFP_KERNEL);
2834                 if (!new_disk_conf) {
2835                         retcode = ERR_NOMEM;
2836                         goto fail_ldev;
2837                 }
2838         }
2839
2840         if (device->ldev->md.al_stripes != rs.al_stripes ||
2841             device->ldev->md.al_stripe_size_4k != rs.al_stripe_size / 4) {
2842                 u32 al_size_k = rs.al_stripes * rs.al_stripe_size;
2843
2844                 if (al_size_k > (16 * 1024 * 1024)) {
2845                         retcode = ERR_MD_LAYOUT_TOO_BIG;
2846                         goto fail_ldev;
2847                 }
2848
2849                 if (al_size_k < MD_32kB_SECT/2) {
2850                         retcode = ERR_MD_LAYOUT_TOO_SMALL;
2851                         goto fail_ldev;
2852                 }
2853
2854                 if (device->state.conn != C_CONNECTED && !rs.resize_force) {
2855                         retcode = ERR_MD_LAYOUT_CONNECTED;
2856                         goto fail_ldev;
2857                 }
2858
2859                 change_al_layout = true;
2860         }
2861
2862         if (device->ldev->known_size != drbd_get_capacity(device->ldev->backing_bdev))
2863                 device->ldev->known_size = drbd_get_capacity(device->ldev->backing_bdev);
2864
2865         if (new_disk_conf) {
2866                 mutex_lock(&device->resource->conf_update);
2867                 old_disk_conf = device->ldev->disk_conf;
2868                 *new_disk_conf = *old_disk_conf;
2869                 new_disk_conf->disk_size = (sector_t)rs.resize_size;
2870                 rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
2871                 mutex_unlock(&device->resource->conf_update);
2872                 kvfree_rcu_mightsleep(old_disk_conf);
2873                 new_disk_conf = NULL;
2874         }
2875
2876         ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
2877         dd = drbd_determine_dev_size(device, ddsf, change_al_layout ? &rs : NULL);
2878         drbd_md_sync(device);
2879         put_ldev(device);
2880         if (dd == DS_ERROR) {
2881                 retcode = ERR_NOMEM_BITMAP;
2882                 goto fail;
2883         } else if (dd == DS_ERROR_SPACE_MD) {
2884                 retcode = ERR_MD_LAYOUT_NO_FIT;
2885                 goto fail;
2886         } else if (dd == DS_ERROR_SHRINK) {
2887                 retcode = ERR_IMPLICIT_SHRINK;
2888                 goto fail;
2889         }
2890
2891         if (device->state.conn == C_CONNECTED) {
2892                 if (dd == DS_GREW)
2893                         set_bit(RESIZE_PENDING, &device->flags);
2894
2895                 drbd_send_uuids(first_peer_device(device));
2896                 drbd_send_sizes(first_peer_device(device), 1, ddsf);
2897         }
2898
2899  fail:
2900         mutex_unlock(&adm_ctx.resource->adm_mutex);
2901  finish:
2902         drbd_adm_finish(&adm_ctx, info, retcode);
2903         return 0;
2904
2905  fail_ldev:
2906         put_ldev(device);
2907         kfree(new_disk_conf);
2908         goto fail;
2909 }
2910
2911 int drbd_adm_resource_opts(struct sk_buff *skb, struct genl_info *info)
2912 {
2913         struct drbd_config_context adm_ctx;
2914         enum drbd_ret_code retcode;
2915         struct res_opts res_opts;
2916         int err;
2917
2918         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_RESOURCE);
2919         if (!adm_ctx.reply_skb)
2920                 return retcode;
2921         if (retcode != NO_ERROR)
2922                 goto fail;
2923
2924         res_opts = adm_ctx.resource->res_opts;
2925         if (should_set_defaults(info))
2926                 set_res_opts_defaults(&res_opts);
2927
2928         err = res_opts_from_attrs(&res_opts, info);
2929         if (err && err != -ENOMSG) {
2930                 retcode = ERR_MANDATORY_TAG;
2931                 drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
2932                 goto fail;
2933         }
2934
2935         mutex_lock(&adm_ctx.resource->adm_mutex);
2936         err = set_resource_options(adm_ctx.resource, &res_opts);
2937         if (err) {
2938                 retcode = ERR_INVALID_REQUEST;
2939                 if (err == -ENOMEM)
2940                         retcode = ERR_NOMEM;
2941         }
2942         mutex_unlock(&adm_ctx.resource->adm_mutex);
2943
2944 fail:
2945         drbd_adm_finish(&adm_ctx, info, retcode);
2946         return 0;
2947 }
2948
2949 int drbd_adm_invalidate(struct sk_buff *skb, struct genl_info *info)
2950 {
2951         struct drbd_config_context adm_ctx;
2952         struct drbd_device *device;
2953         int retcode; /* enum drbd_ret_code rsp. enum drbd_state_rv */
2954
2955         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
2956         if (!adm_ctx.reply_skb)
2957                 return retcode;
2958         if (retcode != NO_ERROR)
2959                 goto out;
2960
2961         device = adm_ctx.device;
2962         if (!get_ldev(device)) {
2963                 retcode = ERR_NO_DISK;
2964                 goto out;
2965         }
2966
2967         mutex_lock(&adm_ctx.resource->adm_mutex);
2968
2969         /* If there is still bitmap IO pending, probably because of a previous
2970          * resync just being finished, wait for it before requesting a new resync.
2971          * Also wait for it's after_state_ch(). */
2972         drbd_suspend_io(device);
2973         wait_event(device->misc_wait, !test_bit(BITMAP_IO, &device->flags));
2974         drbd_flush_workqueue(&first_peer_device(device)->connection->sender_work);
2975
2976         /* If we happen to be C_STANDALONE R_SECONDARY, just change to
2977          * D_INCONSISTENT, and set all bits in the bitmap.  Otherwise,
2978          * try to start a resync handshake as sync target for full sync.
2979          */
2980         if (device->state.conn == C_STANDALONE && device->state.role == R_SECONDARY) {
2981                 retcode = drbd_request_state(device, NS(disk, D_INCONSISTENT));
2982                 if (retcode >= SS_SUCCESS) {
2983                         if (drbd_bitmap_io(device, &drbd_bmio_set_n_write,
2984                                 "set_n_write from invalidate", BM_LOCKED_MASK, NULL))
2985                                 retcode = ERR_IO_MD_DISK;
2986                 }
2987         } else
2988                 retcode = drbd_request_state(device, NS(conn, C_STARTING_SYNC_T));
2989         drbd_resume_io(device);
2990         mutex_unlock(&adm_ctx.resource->adm_mutex);
2991         put_ldev(device);
2992 out:
2993         drbd_adm_finish(&adm_ctx, info, retcode);
2994         return 0;
2995 }
2996
2997 static int drbd_adm_simple_request_state(struct sk_buff *skb, struct genl_info *info,
2998                 union drbd_state mask, union drbd_state val)
2999 {
3000         struct drbd_config_context adm_ctx;
3001         enum drbd_ret_code retcode;
3002
3003         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
3004         if (!adm_ctx.reply_skb)
3005                 return retcode;
3006         if (retcode != NO_ERROR)
3007                 goto out;
3008
3009         mutex_lock(&adm_ctx.resource->adm_mutex);
3010         retcode = drbd_request_state(adm_ctx.device, mask, val);
3011         mutex_unlock(&adm_ctx.resource->adm_mutex);
3012 out:
3013         drbd_adm_finish(&adm_ctx, info, retcode);
3014         return 0;
3015 }
3016
3017 static int drbd_bmio_set_susp_al(struct drbd_device *device,
3018                 struct drbd_peer_device *peer_device) __must_hold(local)
3019 {
3020         int rv;
3021
3022         rv = drbd_bmio_set_n_write(device, peer_device);
3023         drbd_suspend_al(device);
3024         return rv;
3025 }
3026
3027 int drbd_adm_invalidate_peer(struct sk_buff *skb, struct genl_info *info)
3028 {
3029         struct drbd_config_context adm_ctx;
3030         int retcode; /* drbd_ret_code, drbd_state_rv */
3031         struct drbd_device *device;
3032
3033         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
3034         if (!adm_ctx.reply_skb)
3035                 return retcode;
3036         if (retcode != NO_ERROR)
3037                 goto out;
3038
3039         device = adm_ctx.device;
3040         if (!get_ldev(device)) {
3041                 retcode = ERR_NO_DISK;
3042                 goto out;
3043         }
3044
3045         mutex_lock(&adm_ctx.resource->adm_mutex);
3046
3047         /* If there is still bitmap IO pending, probably because of a previous
3048          * resync just being finished, wait for it before requesting a new resync.
3049          * Also wait for it's after_state_ch(). */
3050         drbd_suspend_io(device);
3051         wait_event(device->misc_wait, !test_bit(BITMAP_IO, &device->flags));
3052         drbd_flush_workqueue(&first_peer_device(device)->connection->sender_work);
3053
3054         /* If we happen to be C_STANDALONE R_PRIMARY, just set all bits
3055          * in the bitmap.  Otherwise, try to start a resync handshake
3056          * as sync source for full sync.
3057          */
3058         if (device->state.conn == C_STANDALONE && device->state.role == R_PRIMARY) {
3059                 /* The peer will get a resync upon connect anyways. Just make that
3060                    into a full resync. */
3061                 retcode = drbd_request_state(device, NS(pdsk, D_INCONSISTENT));
3062                 if (retcode >= SS_SUCCESS) {
3063                         if (drbd_bitmap_io(device, &drbd_bmio_set_susp_al,
3064                                 "set_n_write from invalidate_peer",
3065                                 BM_LOCKED_SET_ALLOWED, NULL))
3066                                 retcode = ERR_IO_MD_DISK;
3067                 }
3068         } else
3069                 retcode = drbd_request_state(device, NS(conn, C_STARTING_SYNC_S));
3070         drbd_resume_io(device);
3071         mutex_unlock(&adm_ctx.resource->adm_mutex);
3072         put_ldev(device);
3073 out:
3074         drbd_adm_finish(&adm_ctx, info, retcode);
3075         return 0;
3076 }
3077
3078 int drbd_adm_pause_sync(struct sk_buff *skb, struct genl_info *info)
3079 {
3080         struct drbd_config_context adm_ctx;
3081         enum drbd_ret_code retcode;
3082
3083         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
3084         if (!adm_ctx.reply_skb)
3085                 return retcode;
3086         if (retcode != NO_ERROR)
3087                 goto out;
3088
3089         mutex_lock(&adm_ctx.resource->adm_mutex);
3090         if (drbd_request_state(adm_ctx.device, NS(user_isp, 1)) == SS_NOTHING_TO_DO)
3091                 retcode = ERR_PAUSE_IS_SET;
3092         mutex_unlock(&adm_ctx.resource->adm_mutex);
3093 out:
3094         drbd_adm_finish(&adm_ctx, info, retcode);
3095         return 0;
3096 }
3097
3098 int drbd_adm_resume_sync(struct sk_buff *skb, struct genl_info *info)
3099 {
3100         struct drbd_config_context adm_ctx;
3101         union drbd_dev_state s;
3102         enum drbd_ret_code retcode;
3103
3104         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
3105         if (!adm_ctx.reply_skb)
3106                 return retcode;
3107         if (retcode != NO_ERROR)
3108                 goto out;
3109
3110         mutex_lock(&adm_ctx.resource->adm_mutex);
3111         if (drbd_request_state(adm_ctx.device, NS(user_isp, 0)) == SS_NOTHING_TO_DO) {
3112                 s = adm_ctx.device->state;
3113                 if (s.conn == C_PAUSED_SYNC_S || s.conn == C_PAUSED_SYNC_T) {
3114                         retcode = s.aftr_isp ? ERR_PIC_AFTER_DEP :
3115                                   s.peer_isp ? ERR_PIC_PEER_DEP : ERR_PAUSE_IS_CLEAR;
3116                 } else {
3117                         retcode = ERR_PAUSE_IS_CLEAR;
3118                 }
3119         }
3120         mutex_unlock(&adm_ctx.resource->adm_mutex);
3121 out:
3122         drbd_adm_finish(&adm_ctx, info, retcode);
3123         return 0;
3124 }
3125
3126 int drbd_adm_suspend_io(struct sk_buff *skb, struct genl_info *info)
3127 {
3128         return drbd_adm_simple_request_state(skb, info, NS(susp, 1));
3129 }
3130
3131 int drbd_adm_resume_io(struct sk_buff *skb, struct genl_info *info)
3132 {
3133         struct drbd_config_context adm_ctx;
3134         struct drbd_device *device;
3135         int retcode; /* enum drbd_ret_code rsp. enum drbd_state_rv */
3136
3137         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
3138         if (!adm_ctx.reply_skb)
3139                 return retcode;
3140         if (retcode != NO_ERROR)
3141                 goto out;
3142
3143         mutex_lock(&adm_ctx.resource->adm_mutex);
3144         device = adm_ctx.device;
3145         if (test_bit(NEW_CUR_UUID, &device->flags)) {
3146                 if (get_ldev_if_state(device, D_ATTACHING)) {
3147                         drbd_uuid_new_current(device);
3148                         put_ldev(device);
3149                 } else {
3150                         /* This is effectively a multi-stage "forced down".
3151                          * The NEW_CUR_UUID bit is supposedly only set, if we
3152                          * lost the replication connection, and are configured
3153                          * to freeze IO and wait for some fence-peer handler.
3154                          * So we still don't have a replication connection.
3155                          * And now we don't have a local disk either.  After
3156                          * resume, we will fail all pending and new IO, because
3157                          * we don't have any data anymore.  Which means we will
3158                          * eventually be able to terminate all users of this
3159                          * device, and then take it down.  By bumping the
3160                          * "effective" data uuid, we make sure that you really
3161                          * need to tear down before you reconfigure, we will
3162                          * the refuse to re-connect or re-attach (because no
3163                          * matching real data uuid exists).
3164                          */
3165                         u64 val;
3166                         get_random_bytes(&val, sizeof(u64));
3167                         drbd_set_ed_uuid(device, val);
3168                         drbd_warn(device, "Resumed without access to data; please tear down before attempting to re-configure.\n");
3169                 }
3170                 clear_bit(NEW_CUR_UUID, &device->flags);
3171         }
3172         drbd_suspend_io(device);
3173         retcode = drbd_request_state(device, NS3(susp, 0, susp_nod, 0, susp_fen, 0));
3174         if (retcode == SS_SUCCESS) {
3175                 if (device->state.conn < C_CONNECTED)
3176                         tl_clear(first_peer_device(device)->connection);
3177                 if (device->state.disk == D_DISKLESS || device->state.disk == D_FAILED)
3178                         tl_restart(first_peer_device(device)->connection, FAIL_FROZEN_DISK_IO);
3179         }
3180         drbd_resume_io(device);
3181         mutex_unlock(&adm_ctx.resource->adm_mutex);
3182 out:
3183         drbd_adm_finish(&adm_ctx, info, retcode);
3184         return 0;
3185 }
3186
3187 int drbd_adm_outdate(struct sk_buff *skb, struct genl_info *info)
3188 {
3189         return drbd_adm_simple_request_state(skb, info, NS(disk, D_OUTDATED));
3190 }
3191
3192 static int nla_put_drbd_cfg_context(struct sk_buff *skb,
3193                                     struct drbd_resource *resource,
3194                                     struct drbd_connection *connection,
3195                                     struct drbd_device *device)
3196 {
3197         struct nlattr *nla;
3198         nla = nla_nest_start_noflag(skb, DRBD_NLA_CFG_CONTEXT);
3199         if (!nla)
3200                 goto nla_put_failure;
3201         if (device &&
3202             nla_put_u32(skb, T_ctx_volume, device->vnr))
3203                 goto nla_put_failure;
3204         if (nla_put_string(skb, T_ctx_resource_name, resource->name))
3205                 goto nla_put_failure;
3206         if (connection) {
3207                 if (connection->my_addr_len &&
3208                     nla_put(skb, T_ctx_my_addr, connection->my_addr_len, &connection->my_addr))
3209                         goto nla_put_failure;
3210                 if (connection->peer_addr_len &&
3211                     nla_put(skb, T_ctx_peer_addr, connection->peer_addr_len, &connection->peer_addr))
3212                         goto nla_put_failure;
3213         }
3214         nla_nest_end(skb, nla);
3215         return 0;
3216
3217 nla_put_failure:
3218         if (nla)
3219                 nla_nest_cancel(skb, nla);
3220         return -EMSGSIZE;
3221 }
3222
3223 /*
3224  * The generic netlink dump callbacks are called outside the genl_lock(), so
3225  * they cannot use the simple attribute parsing code which uses global
3226  * attribute tables.
3227  */
3228 static struct nlattr *find_cfg_context_attr(const struct nlmsghdr *nlh, int attr)
3229 {
3230         const unsigned hdrlen = GENL_HDRLEN + GENL_MAGIC_FAMILY_HDRSZ;
3231         const int maxtype = ARRAY_SIZE(drbd_cfg_context_nl_policy) - 1;
3232         struct nlattr *nla;
3233
3234         nla = nla_find(nlmsg_attrdata(nlh, hdrlen), nlmsg_attrlen(nlh, hdrlen),
3235                        DRBD_NLA_CFG_CONTEXT);
3236         if (!nla)
3237                 return NULL;
3238         return drbd_nla_find_nested(maxtype, nla, __nla_type(attr));
3239 }
3240
3241 static void resource_to_info(struct resource_info *, struct drbd_resource *);
3242
3243 int drbd_adm_dump_resources(struct sk_buff *skb, struct netlink_callback *cb)
3244 {
3245         struct drbd_genlmsghdr *dh;
3246         struct drbd_resource *resource;
3247         struct resource_info resource_info;
3248         struct resource_statistics resource_statistics;
3249         int err;
3250
3251         rcu_read_lock();
3252         if (cb->args[0]) {
3253                 for_each_resource_rcu(resource, &drbd_resources)
3254                         if (resource == (struct drbd_resource *)cb->args[0])
3255                                 goto found_resource;
3256                 err = 0;  /* resource was probably deleted */
3257                 goto out;
3258         }
3259         resource = list_entry(&drbd_resources,
3260                               struct drbd_resource, resources);
3261
3262 found_resource:
3263         list_for_each_entry_continue_rcu(resource, &drbd_resources, resources) {
3264                 goto put_result;
3265         }
3266         err = 0;
3267         goto out;
3268
3269 put_result:
3270         dh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
3271                         cb->nlh->nlmsg_seq, &drbd_genl_family,
3272                         NLM_F_MULTI, DRBD_ADM_GET_RESOURCES);
3273         err = -ENOMEM;
3274         if (!dh)
3275                 goto out;
3276         dh->minor = -1U;
3277         dh->ret_code = NO_ERROR;
3278         err = nla_put_drbd_cfg_context(skb, resource, NULL, NULL);
3279         if (err)
3280                 goto out;
3281         err = res_opts_to_skb(skb, &resource->res_opts, !capable(CAP_SYS_ADMIN));
3282         if (err)
3283                 goto out;
3284         resource_to_info(&resource_info, resource);
3285         err = resource_info_to_skb(skb, &resource_info, !capable(CAP_SYS_ADMIN));
3286         if (err)
3287                 goto out;
3288         resource_statistics.res_stat_write_ordering = resource->write_ordering;
3289         err = resource_statistics_to_skb(skb, &resource_statistics, !capable(CAP_SYS_ADMIN));
3290         if (err)
3291                 goto out;
3292         cb->args[0] = (long)resource;
3293         genlmsg_end(skb, dh);
3294         err = 0;
3295
3296 out:
3297         rcu_read_unlock();
3298         if (err)
3299                 return err;
3300         return skb->len;
3301 }
3302
3303 static void device_to_statistics(struct device_statistics *s,
3304                                  struct drbd_device *device)
3305 {
3306         memset(s, 0, sizeof(*s));
3307         s->dev_upper_blocked = !may_inc_ap_bio(device);
3308         if (get_ldev(device)) {
3309                 struct drbd_md *md = &device->ldev->md;
3310                 u64 *history_uuids = (u64 *)s->history_uuids;
3311                 int n;
3312
3313                 spin_lock_irq(&md->uuid_lock);
3314                 s->dev_current_uuid = md->uuid[UI_CURRENT];
3315                 BUILD_BUG_ON(sizeof(s->history_uuids) < UI_HISTORY_END - UI_HISTORY_START + 1);
3316                 for (n = 0; n < UI_HISTORY_END - UI_HISTORY_START + 1; n++)
3317                         history_uuids[n] = md->uuid[UI_HISTORY_START + n];
3318                 for (; n < HISTORY_UUIDS; n++)
3319                         history_uuids[n] = 0;
3320                 s->history_uuids_len = HISTORY_UUIDS;
3321                 spin_unlock_irq(&md->uuid_lock);
3322
3323                 s->dev_disk_flags = md->flags;
3324                 put_ldev(device);
3325         }
3326         s->dev_size = get_capacity(device->vdisk);
3327         s->dev_read = device->read_cnt;
3328         s->dev_write = device->writ_cnt;
3329         s->dev_al_writes = device->al_writ_cnt;
3330         s->dev_bm_writes = device->bm_writ_cnt;
3331         s->dev_upper_pending = atomic_read(&device->ap_bio_cnt);
3332         s->dev_lower_pending = atomic_read(&device->local_cnt);
3333         s->dev_al_suspended = test_bit(AL_SUSPENDED, &device->flags);
3334         s->dev_exposed_data_uuid = device->ed_uuid;
3335 }
3336
3337 static int put_resource_in_arg0(struct netlink_callback *cb, int holder_nr)
3338 {
3339         if (cb->args[0]) {
3340                 struct drbd_resource *resource =
3341                         (struct drbd_resource *)cb->args[0];
3342                 kref_put(&resource->kref, drbd_destroy_resource);
3343         }
3344
3345         return 0;
3346 }
3347
3348 int drbd_adm_dump_devices_done(struct netlink_callback *cb) {
3349         return put_resource_in_arg0(cb, 7);
3350 }
3351
3352 static void device_to_info(struct device_info *, struct drbd_device *);
3353
3354 int drbd_adm_dump_devices(struct sk_buff *skb, struct netlink_callback *cb)
3355 {
3356         struct nlattr *resource_filter;
3357         struct drbd_resource *resource;
3358         struct drbd_device *device;
3359         int minor, err, retcode;
3360         struct drbd_genlmsghdr *dh;
3361         struct device_info device_info;
3362         struct device_statistics device_statistics;
3363         struct idr *idr_to_search;
3364
3365         resource = (struct drbd_resource *)cb->args[0];
3366         if (!cb->args[0] && !cb->args[1]) {
3367                 resource_filter = find_cfg_context_attr(cb->nlh, T_ctx_resource_name);
3368                 if (resource_filter) {
3369                         retcode = ERR_RES_NOT_KNOWN;
3370                         resource = drbd_find_resource(nla_data(resource_filter));
3371                         if (!resource)
3372                                 goto put_result;
3373                         cb->args[0] = (long)resource;
3374                 }
3375         }
3376
3377         rcu_read_lock();
3378         minor = cb->args[1];
3379         idr_to_search = resource ? &resource->devices : &drbd_devices;
3380         device = idr_get_next(idr_to_search, &minor);
3381         if (!device) {
3382                 err = 0;
3383                 goto out;
3384         }
3385         idr_for_each_entry_continue(idr_to_search, device, minor) {
3386                 retcode = NO_ERROR;
3387                 goto put_result;  /* only one iteration */
3388         }
3389         err = 0;
3390         goto out;  /* no more devices */
3391
3392 put_result:
3393         dh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
3394                         cb->nlh->nlmsg_seq, &drbd_genl_family,
3395                         NLM_F_MULTI, DRBD_ADM_GET_DEVICES);
3396         err = -ENOMEM;
3397         if (!dh)
3398                 goto out;
3399         dh->ret_code = retcode;
3400         dh->minor = -1U;
3401         if (retcode == NO_ERROR) {
3402                 dh->minor = device->minor;
3403                 err = nla_put_drbd_cfg_context(skb, device->resource, NULL, device);
3404                 if (err)
3405                         goto out;
3406                 if (get_ldev(device)) {
3407                         struct disk_conf *disk_conf =
3408                                 rcu_dereference(device->ldev->disk_conf);
3409
3410                         err = disk_conf_to_skb(skb, disk_conf, !capable(CAP_SYS_ADMIN));
3411                         put_ldev(device);
3412                         if (err)
3413                                 goto out;
3414                 }
3415                 device_to_info(&device_info, device);
3416                 err = device_info_to_skb(skb, &device_info, !capable(CAP_SYS_ADMIN));
3417                 if (err)
3418                         goto out;
3419
3420                 device_to_statistics(&device_statistics, device);
3421                 err = device_statistics_to_skb(skb, &device_statistics, !capable(CAP_SYS_ADMIN));
3422                 if (err)
3423                         goto out;
3424                 cb->args[1] = minor + 1;
3425         }
3426         genlmsg_end(skb, dh);
3427         err = 0;
3428
3429 out:
3430         rcu_read_unlock();
3431         if (err)
3432                 return err;
3433         return skb->len;
3434 }
3435
3436 int drbd_adm_dump_connections_done(struct netlink_callback *cb)
3437 {
3438         return put_resource_in_arg0(cb, 6);
3439 }
3440
3441 enum { SINGLE_RESOURCE, ITERATE_RESOURCES };
3442
3443 int drbd_adm_dump_connections(struct sk_buff *skb, struct netlink_callback *cb)
3444 {
3445         struct nlattr *resource_filter;
3446         struct drbd_resource *resource = NULL, *next_resource;
3447         struct drbd_connection *connection;
3448         int err = 0, retcode;
3449         struct drbd_genlmsghdr *dh;
3450         struct connection_info connection_info;
3451         struct connection_statistics connection_statistics;
3452
3453         rcu_read_lock();
3454         resource = (struct drbd_resource *)cb->args[0];
3455         if (!cb->args[0]) {
3456                 resource_filter = find_cfg_context_attr(cb->nlh, T_ctx_resource_name);
3457                 if (resource_filter) {
3458                         retcode = ERR_RES_NOT_KNOWN;
3459                         resource = drbd_find_resource(nla_data(resource_filter));
3460                         if (!resource)
3461                                 goto put_result;
3462                         cb->args[0] = (long)resource;
3463                         cb->args[1] = SINGLE_RESOURCE;
3464                 }
3465         }
3466         if (!resource) {
3467                 if (list_empty(&drbd_resources))
3468                         goto out;
3469                 resource = list_first_entry(&drbd_resources, struct drbd_resource, resources);
3470                 kref_get(&resource->kref);
3471                 cb->args[0] = (long)resource;
3472                 cb->args[1] = ITERATE_RESOURCES;
3473         }
3474
3475     next_resource:
3476         rcu_read_unlock();
3477         mutex_lock(&resource->conf_update);
3478         rcu_read_lock();
3479         if (cb->args[2]) {
3480                 for_each_connection_rcu(connection, resource)
3481                         if (connection == (struct drbd_connection *)cb->args[2])
3482                                 goto found_connection;
3483                 /* connection was probably deleted */
3484                 goto no_more_connections;
3485         }
3486         connection = list_entry(&resource->connections, struct drbd_connection, connections);
3487
3488 found_connection:
3489         list_for_each_entry_continue_rcu(connection, &resource->connections, connections) {
3490                 if (!has_net_conf(connection))
3491                         continue;
3492                 retcode = NO_ERROR;
3493                 goto put_result;  /* only one iteration */
3494         }
3495
3496 no_more_connections:
3497         if (cb->args[1] == ITERATE_RESOURCES) {
3498                 for_each_resource_rcu(next_resource, &drbd_resources) {
3499                         if (next_resource == resource)
3500                                 goto found_resource;
3501                 }
3502                 /* resource was probably deleted */
3503         }
3504         goto out;
3505
3506 found_resource:
3507         list_for_each_entry_continue_rcu(next_resource, &drbd_resources, resources) {
3508                 mutex_unlock(&resource->conf_update);
3509                 kref_put(&resource->kref, drbd_destroy_resource);
3510                 resource = next_resource;
3511                 kref_get(&resource->kref);
3512                 cb->args[0] = (long)resource;
3513                 cb->args[2] = 0;
3514                 goto next_resource;
3515         }
3516         goto out;  /* no more resources */
3517
3518 put_result:
3519         dh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
3520                         cb->nlh->nlmsg_seq, &drbd_genl_family,
3521                         NLM_F_MULTI, DRBD_ADM_GET_CONNECTIONS);
3522         err = -ENOMEM;
3523         if (!dh)
3524                 goto out;
3525         dh->ret_code = retcode;
3526         dh->minor = -1U;
3527         if (retcode == NO_ERROR) {
3528                 struct net_conf *net_conf;
3529
3530                 err = nla_put_drbd_cfg_context(skb, resource, connection, NULL);
3531                 if (err)
3532                         goto out;
3533                 net_conf = rcu_dereference(connection->net_conf);
3534                 if (net_conf) {
3535                         err = net_conf_to_skb(skb, net_conf, !capable(CAP_SYS_ADMIN));
3536                         if (err)
3537                                 goto out;
3538                 }
3539                 connection_to_info(&connection_info, connection);
3540                 err = connection_info_to_skb(skb, &connection_info, !capable(CAP_SYS_ADMIN));
3541                 if (err)
3542                         goto out;
3543                 connection_statistics.conn_congested = test_bit(NET_CONGESTED, &connection->flags);
3544                 err = connection_statistics_to_skb(skb, &connection_statistics, !capable(CAP_SYS_ADMIN));
3545                 if (err)
3546                         goto out;
3547                 cb->args[2] = (long)connection;
3548         }
3549         genlmsg_end(skb, dh);
3550         err = 0;
3551
3552 out:
3553         rcu_read_unlock();
3554         if (resource)
3555                 mutex_unlock(&resource->conf_update);
3556         if (err)
3557                 return err;
3558         return skb->len;
3559 }
3560
3561 enum mdf_peer_flag {
3562         MDF_PEER_CONNECTED =    1 << 0,
3563         MDF_PEER_OUTDATED =     1 << 1,
3564         MDF_PEER_FENCING =      1 << 2,
3565         MDF_PEER_FULL_SYNC =    1 << 3,
3566 };
3567
3568 static void peer_device_to_statistics(struct peer_device_statistics *s,
3569                                       struct drbd_peer_device *peer_device)
3570 {
3571         struct drbd_device *device = peer_device->device;
3572
3573         memset(s, 0, sizeof(*s));
3574         s->peer_dev_received = device->recv_cnt;
3575         s->peer_dev_sent = device->send_cnt;
3576         s->peer_dev_pending = atomic_read(&device->ap_pending_cnt) +
3577                               atomic_read(&device->rs_pending_cnt);
3578         s->peer_dev_unacked = atomic_read(&device->unacked_cnt);
3579         s->peer_dev_out_of_sync = drbd_bm_total_weight(device) << (BM_BLOCK_SHIFT - 9);
3580         s->peer_dev_resync_failed = device->rs_failed << (BM_BLOCK_SHIFT - 9);
3581         if (get_ldev(device)) {
3582                 struct drbd_md *md = &device->ldev->md;
3583
3584                 spin_lock_irq(&md->uuid_lock);
3585                 s->peer_dev_bitmap_uuid = md->uuid[UI_BITMAP];
3586                 spin_unlock_irq(&md->uuid_lock);
3587                 s->peer_dev_flags =
3588                         (drbd_md_test_flag(device->ldev, MDF_CONNECTED_IND) ?
3589                                 MDF_PEER_CONNECTED : 0) +
3590                         (drbd_md_test_flag(device->ldev, MDF_CONSISTENT) &&
3591                          !drbd_md_test_flag(device->ldev, MDF_WAS_UP_TO_DATE) ?
3592                                 MDF_PEER_OUTDATED : 0) +
3593                         /* FIXME: MDF_PEER_FENCING? */
3594                         (drbd_md_test_flag(device->ldev, MDF_FULL_SYNC) ?
3595                                 MDF_PEER_FULL_SYNC : 0);
3596                 put_ldev(device);
3597         }
3598 }
3599
3600 int drbd_adm_dump_peer_devices_done(struct netlink_callback *cb)
3601 {
3602         return put_resource_in_arg0(cb, 9);
3603 }
3604
3605 int drbd_adm_dump_peer_devices(struct sk_buff *skb, struct netlink_callback *cb)
3606 {
3607         struct nlattr *resource_filter;
3608         struct drbd_resource *resource;
3609         struct drbd_device *device;
3610         struct drbd_peer_device *peer_device = NULL;
3611         int minor, err, retcode;
3612         struct drbd_genlmsghdr *dh;
3613         struct idr *idr_to_search;
3614
3615         resource = (struct drbd_resource *)cb->args[0];
3616         if (!cb->args[0] && !cb->args[1]) {
3617                 resource_filter = find_cfg_context_attr(cb->nlh, T_ctx_resource_name);
3618                 if (resource_filter) {
3619                         retcode = ERR_RES_NOT_KNOWN;
3620                         resource = drbd_find_resource(nla_data(resource_filter));
3621                         if (!resource)
3622                                 goto put_result;
3623                 }
3624                 cb->args[0] = (long)resource;
3625         }
3626
3627         rcu_read_lock();
3628         minor = cb->args[1];
3629         idr_to_search = resource ? &resource->devices : &drbd_devices;
3630         device = idr_find(idr_to_search, minor);
3631         if (!device) {
3632 next_device:
3633                 minor++;
3634                 cb->args[2] = 0;
3635                 device = idr_get_next(idr_to_search, &minor);
3636                 if (!device) {
3637                         err = 0;
3638                         goto out;
3639                 }
3640         }
3641         if (cb->args[2]) {
3642                 for_each_peer_device(peer_device, device)
3643                         if (peer_device == (struct drbd_peer_device *)cb->args[2])
3644                                 goto found_peer_device;
3645                 /* peer device was probably deleted */
3646                 goto next_device;
3647         }
3648         /* Make peer_device point to the list head (not the first entry). */
3649         peer_device = list_entry(&device->peer_devices, struct drbd_peer_device, peer_devices);
3650
3651 found_peer_device:
3652         list_for_each_entry_continue_rcu(peer_device, &device->peer_devices, peer_devices) {
3653                 if (!has_net_conf(peer_device->connection))
3654                         continue;
3655                 retcode = NO_ERROR;
3656                 goto put_result;  /* only one iteration */
3657         }
3658         goto next_device;
3659
3660 put_result:
3661         dh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
3662                         cb->nlh->nlmsg_seq, &drbd_genl_family,
3663                         NLM_F_MULTI, DRBD_ADM_GET_PEER_DEVICES);
3664         err = -ENOMEM;
3665         if (!dh)
3666                 goto out;
3667         dh->ret_code = retcode;
3668         dh->minor = -1U;
3669         if (retcode == NO_ERROR) {
3670                 struct peer_device_info peer_device_info;
3671                 struct peer_device_statistics peer_device_statistics;
3672
3673                 dh->minor = minor;
3674                 err = nla_put_drbd_cfg_context(skb, device->resource, peer_device->connection, device);
3675                 if (err)
3676                         goto out;
3677                 peer_device_to_info(&peer_device_info, peer_device);
3678                 err = peer_device_info_to_skb(skb, &peer_device_info, !capable(CAP_SYS_ADMIN));
3679                 if (err)
3680                         goto out;
3681                 peer_device_to_statistics(&peer_device_statistics, peer_device);
3682                 err = peer_device_statistics_to_skb(skb, &peer_device_statistics, !capable(CAP_SYS_ADMIN));
3683                 if (err)
3684                         goto out;
3685                 cb->args[1] = minor;
3686                 cb->args[2] = (long)peer_device;
3687         }
3688         genlmsg_end(skb, dh);
3689         err = 0;
3690
3691 out:
3692         rcu_read_unlock();
3693         if (err)
3694                 return err;
3695         return skb->len;
3696 }
3697 /*
3698  * Return the connection of @resource if @resource has exactly one connection.
3699  */
3700 static struct drbd_connection *the_only_connection(struct drbd_resource *resource)
3701 {
3702         struct list_head *connections = &resource->connections;
3703
3704         if (list_empty(connections) || connections->next->next != connections)
3705                 return NULL;
3706         return list_first_entry(&resource->connections, struct drbd_connection, connections);
3707 }
3708
3709 static int nla_put_status_info(struct sk_buff *skb, struct drbd_device *device,
3710                 const struct sib_info *sib)
3711 {
3712         struct drbd_resource *resource = device->resource;
3713         struct state_info *si = NULL; /* for sizeof(si->member); */
3714         struct nlattr *nla;
3715         int got_ldev;
3716         int err = 0;
3717         int exclude_sensitive;
3718
3719         /* If sib != NULL, this is drbd_bcast_event, which anyone can listen
3720          * to.  So we better exclude_sensitive information.
3721          *
3722          * If sib == NULL, this is drbd_adm_get_status, executed synchronously
3723          * in the context of the requesting user process. Exclude sensitive
3724          * information, unless current has superuser.
3725          *
3726          * NOTE: for drbd_adm_get_status_all(), this is a netlink dump, and
3727          * relies on the current implementation of netlink_dump(), which
3728          * executes the dump callback successively from netlink_recvmsg(),
3729          * always in the context of the receiving process */
3730         exclude_sensitive = sib || !capable(CAP_SYS_ADMIN);
3731
3732         got_ldev = get_ldev(device);
3733
3734         /* We need to add connection name and volume number information still.
3735          * Minor number is in drbd_genlmsghdr. */
3736         if (nla_put_drbd_cfg_context(skb, resource, the_only_connection(resource), device))
3737                 goto nla_put_failure;
3738
3739         if (res_opts_to_skb(skb, &device->resource->res_opts, exclude_sensitive))
3740                 goto nla_put_failure;
3741
3742         rcu_read_lock();
3743         if (got_ldev) {
3744                 struct disk_conf *disk_conf;
3745
3746                 disk_conf = rcu_dereference(device->ldev->disk_conf);
3747                 err = disk_conf_to_skb(skb, disk_conf, exclude_sensitive);
3748         }
3749         if (!err) {
3750                 struct net_conf *nc;
3751
3752                 nc = rcu_dereference(first_peer_device(device)->connection->net_conf);
3753                 if (nc)
3754                         err = net_conf_to_skb(skb, nc, exclude_sensitive);
3755         }
3756         rcu_read_unlock();
3757         if (err)
3758                 goto nla_put_failure;
3759
3760         nla = nla_nest_start_noflag(skb, DRBD_NLA_STATE_INFO);
3761         if (!nla)
3762                 goto nla_put_failure;
3763         if (nla_put_u32(skb, T_sib_reason, sib ? sib->sib_reason : SIB_GET_STATUS_REPLY) ||
3764             nla_put_u32(skb, T_current_state, device->state.i) ||
3765             nla_put_u64_0pad(skb, T_ed_uuid, device->ed_uuid) ||
3766             nla_put_u64_0pad(skb, T_capacity, get_capacity(device->vdisk)) ||
3767             nla_put_u64_0pad(skb, T_send_cnt, device->send_cnt) ||
3768             nla_put_u64_0pad(skb, T_recv_cnt, device->recv_cnt) ||
3769             nla_put_u64_0pad(skb, T_read_cnt, device->read_cnt) ||
3770             nla_put_u64_0pad(skb, T_writ_cnt, device->writ_cnt) ||
3771             nla_put_u64_0pad(skb, T_al_writ_cnt, device->al_writ_cnt) ||
3772             nla_put_u64_0pad(skb, T_bm_writ_cnt, device->bm_writ_cnt) ||
3773             nla_put_u32(skb, T_ap_bio_cnt, atomic_read(&device->ap_bio_cnt)) ||
3774             nla_put_u32(skb, T_ap_pending_cnt, atomic_read(&device->ap_pending_cnt)) ||
3775             nla_put_u32(skb, T_rs_pending_cnt, atomic_read(&device->rs_pending_cnt)))
3776                 goto nla_put_failure;
3777
3778         if (got_ldev) {
3779                 int err;
3780
3781                 spin_lock_irq(&device->ldev->md.uuid_lock);
3782                 err = nla_put(skb, T_uuids, sizeof(si->uuids), device->ldev->md.uuid);
3783                 spin_unlock_irq(&device->ldev->md.uuid_lock);
3784
3785                 if (err)
3786                         goto nla_put_failure;
3787
3788                 if (nla_put_u32(skb, T_disk_flags, device->ldev->md.flags) ||
3789                     nla_put_u64_0pad(skb, T_bits_total, drbd_bm_bits(device)) ||
3790                     nla_put_u64_0pad(skb, T_bits_oos,
3791                                      drbd_bm_total_weight(device)))
3792                         goto nla_put_failure;
3793                 if (C_SYNC_SOURCE <= device->state.conn &&
3794                     C_PAUSED_SYNC_T >= device->state.conn) {
3795                         if (nla_put_u64_0pad(skb, T_bits_rs_total,
3796                                              device->rs_total) ||
3797                             nla_put_u64_0pad(skb, T_bits_rs_failed,
3798                                              device->rs_failed))
3799                                 goto nla_put_failure;
3800                 }
3801         }
3802
3803         if (sib) {
3804                 switch(sib->sib_reason) {
3805                 case SIB_SYNC_PROGRESS:
3806                 case SIB_GET_STATUS_REPLY:
3807                         break;
3808                 case SIB_STATE_CHANGE:
3809                         if (nla_put_u32(skb, T_prev_state, sib->os.i) ||
3810                             nla_put_u32(skb, T_new_state, sib->ns.i))
3811                                 goto nla_put_failure;
3812                         break;
3813                 case SIB_HELPER_POST:
3814                         if (nla_put_u32(skb, T_helper_exit_code,
3815                                         sib->helper_exit_code))
3816                                 goto nla_put_failure;
3817                         fallthrough;
3818                 case SIB_HELPER_PRE:
3819                         if (nla_put_string(skb, T_helper, sib->helper_name))
3820                                 goto nla_put_failure;
3821                         break;
3822                 }
3823         }
3824         nla_nest_end(skb, nla);
3825
3826         if (0)
3827 nla_put_failure:
3828                 err = -EMSGSIZE;
3829         if (got_ldev)
3830                 put_ldev(device);
3831         return err;
3832 }
3833
3834 int drbd_adm_get_status(struct sk_buff *skb, struct genl_info *info)
3835 {
3836         struct drbd_config_context adm_ctx;
3837         enum drbd_ret_code retcode;
3838         int err;
3839
3840         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
3841         if (!adm_ctx.reply_skb)
3842                 return retcode;
3843         if (retcode != NO_ERROR)
3844                 goto out;
3845
3846         err = nla_put_status_info(adm_ctx.reply_skb, adm_ctx.device, NULL);
3847         if (err) {
3848                 nlmsg_free(adm_ctx.reply_skb);
3849                 return err;
3850         }
3851 out:
3852         drbd_adm_finish(&adm_ctx, info, retcode);
3853         return 0;
3854 }
3855
3856 static int get_one_status(struct sk_buff *skb, struct netlink_callback *cb)
3857 {
3858         struct drbd_device *device;
3859         struct drbd_genlmsghdr *dh;
3860         struct drbd_resource *pos = (struct drbd_resource *)cb->args[0];
3861         struct drbd_resource *resource = NULL;
3862         struct drbd_resource *tmp;
3863         unsigned volume = cb->args[1];
3864
3865         /* Open coded, deferred, iteration:
3866          * for_each_resource_safe(resource, tmp, &drbd_resources) {
3867          *      connection = "first connection of resource or undefined";
3868          *      idr_for_each_entry(&resource->devices, device, i) {
3869          *        ...
3870          *      }
3871          * }
3872          * where resource is cb->args[0];
3873          * and i is cb->args[1];
3874          *
3875          * cb->args[2] indicates if we shall loop over all resources,
3876          * or just dump all volumes of a single resource.
3877          *
3878          * This may miss entries inserted after this dump started,
3879          * or entries deleted before they are reached.
3880          *
3881          * We need to make sure the device won't disappear while
3882          * we are looking at it, and revalidate our iterators
3883          * on each iteration.
3884          */
3885
3886         /* synchronize with conn_create()/drbd_destroy_connection() */
3887         rcu_read_lock();
3888         /* revalidate iterator position */
3889         for_each_resource_rcu(tmp, &drbd_resources) {
3890                 if (pos == NULL) {
3891                         /* first iteration */
3892                         pos = tmp;
3893                         resource = pos;
3894                         break;
3895                 }
3896                 if (tmp == pos) {
3897                         resource = pos;
3898                         break;
3899                 }
3900         }
3901         if (resource) {
3902 next_resource:
3903                 device = idr_get_next(&resource->devices, &volume);
3904                 if (!device) {
3905                         /* No more volumes to dump on this resource.
3906                          * Advance resource iterator. */
3907                         pos = list_entry_rcu(resource->resources.next,
3908                                              struct drbd_resource, resources);
3909                         /* Did we dump any volume of this resource yet? */
3910                         if (volume != 0) {
3911                                 /* If we reached the end of the list,
3912                                  * or only a single resource dump was requested,
3913                                  * we are done. */
3914                                 if (&pos->resources == &drbd_resources || cb->args[2])
3915                                         goto out;
3916                                 volume = 0;
3917                                 resource = pos;
3918                                 goto next_resource;
3919                         }
3920                 }
3921
3922                 dh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
3923                                 cb->nlh->nlmsg_seq, &drbd_genl_family,
3924                                 NLM_F_MULTI, DRBD_ADM_GET_STATUS);
3925                 if (!dh)
3926                         goto out;
3927
3928                 if (!device) {
3929                         /* This is a connection without a single volume.
3930                          * Suprisingly enough, it may have a network
3931                          * configuration. */
3932                         struct drbd_connection *connection;
3933
3934                         dh->minor = -1U;
3935                         dh->ret_code = NO_ERROR;
3936                         connection = the_only_connection(resource);
3937                         if (nla_put_drbd_cfg_context(skb, resource, connection, NULL))
3938                                 goto cancel;
3939                         if (connection) {
3940                                 struct net_conf *nc;
3941
3942                                 nc = rcu_dereference(connection->net_conf);
3943                                 if (nc && net_conf_to_skb(skb, nc, 1) != 0)
3944                                         goto cancel;
3945                         }
3946                         goto done;
3947                 }
3948
3949                 D_ASSERT(device, device->vnr == volume);
3950                 D_ASSERT(device, device->resource == resource);
3951
3952                 dh->minor = device_to_minor(device);
3953                 dh->ret_code = NO_ERROR;
3954
3955                 if (nla_put_status_info(skb, device, NULL)) {
3956 cancel:
3957                         genlmsg_cancel(skb, dh);
3958                         goto out;
3959                 }
3960 done:
3961                 genlmsg_end(skb, dh);
3962         }
3963
3964 out:
3965         rcu_read_unlock();
3966         /* where to start the next iteration */
3967         cb->args[0] = (long)pos;
3968         cb->args[1] = (pos == resource) ? volume + 1 : 0;
3969
3970         /* No more resources/volumes/minors found results in an empty skb.
3971          * Which will terminate the dump. */
3972         return skb->len;
3973 }
3974
3975 /*
3976  * Request status of all resources, or of all volumes within a single resource.
3977  *
3978  * This is a dump, as the answer may not fit in a single reply skb otherwise.
3979  * Which means we cannot use the family->attrbuf or other such members, because
3980  * dump is NOT protected by the genl_lock().  During dump, we only have access
3981  * to the incoming skb, and need to opencode "parsing" of the nlattr payload.
3982  *
3983  * Once things are setup properly, we call into get_one_status().
3984  */
3985 int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb)
3986 {
3987         const unsigned hdrlen = GENL_HDRLEN + GENL_MAGIC_FAMILY_HDRSZ;
3988         struct nlattr *nla;
3989         const char *resource_name;
3990         struct drbd_resource *resource;
3991         int maxtype;
3992
3993         /* Is this a followup call? */
3994         if (cb->args[0]) {
3995                 /* ... of a single resource dump,
3996                  * and the resource iterator has been advanced already? */
3997                 if (cb->args[2] && cb->args[2] != cb->args[0])
3998                         return 0; /* DONE. */
3999                 goto dump;
4000         }
4001
4002         /* First call (from netlink_dump_start).  We need to figure out
4003          * which resource(s) the user wants us to dump. */
4004         nla = nla_find(nlmsg_attrdata(cb->nlh, hdrlen),
4005                         nlmsg_attrlen(cb->nlh, hdrlen),
4006                         DRBD_NLA_CFG_CONTEXT);
4007
4008         /* No explicit context given.  Dump all. */
4009         if (!nla)
4010                 goto dump;
4011         maxtype = ARRAY_SIZE(drbd_cfg_context_nl_policy) - 1;
4012         nla = drbd_nla_find_nested(maxtype, nla, __nla_type(T_ctx_resource_name));
4013         if (IS_ERR(nla))
4014                 return PTR_ERR(nla);
4015         /* context given, but no name present? */
4016         if (!nla)
4017                 return -EINVAL;
4018         resource_name = nla_data(nla);
4019         if (!*resource_name)
4020                 return -ENODEV;
4021         resource = drbd_find_resource(resource_name);
4022         if (!resource)
4023                 return -ENODEV;
4024
4025         kref_put(&resource->kref, drbd_destroy_resource); /* get_one_status() revalidates the resource */
4026
4027         /* prime iterators, and set "filter" mode mark:
4028          * only dump this connection. */
4029         cb->args[0] = (long)resource;
4030         /* cb->args[1] = 0; passed in this way. */
4031         cb->args[2] = (long)resource;
4032
4033 dump:
4034         return get_one_status(skb, cb);
4035 }
4036
4037 int drbd_adm_get_timeout_type(struct sk_buff *skb, struct genl_info *info)
4038 {
4039         struct drbd_config_context adm_ctx;
4040         enum drbd_ret_code retcode;
4041         struct timeout_parms tp;
4042         int err;
4043
4044         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
4045         if (!adm_ctx.reply_skb)
4046                 return retcode;
4047         if (retcode != NO_ERROR)
4048                 goto out;
4049
4050         tp.timeout_type =
4051                 adm_ctx.device->state.pdsk == D_OUTDATED ? UT_PEER_OUTDATED :
4052                 test_bit(USE_DEGR_WFC_T, &adm_ctx.device->flags) ? UT_DEGRADED :
4053                 UT_DEFAULT;
4054
4055         err = timeout_parms_to_priv_skb(adm_ctx.reply_skb, &tp);
4056         if (err) {
4057                 nlmsg_free(adm_ctx.reply_skb);
4058                 return err;
4059         }
4060 out:
4061         drbd_adm_finish(&adm_ctx, info, retcode);
4062         return 0;
4063 }
4064
4065 int drbd_adm_start_ov(struct sk_buff *skb, struct genl_info *info)
4066 {
4067         struct drbd_config_context adm_ctx;
4068         struct drbd_device *device;
4069         enum drbd_ret_code retcode;
4070         struct start_ov_parms parms;
4071
4072         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
4073         if (!adm_ctx.reply_skb)
4074                 return retcode;
4075         if (retcode != NO_ERROR)
4076                 goto out;
4077
4078         device = adm_ctx.device;
4079
4080         /* resume from last known position, if possible */
4081         parms.ov_start_sector = device->ov_start_sector;
4082         parms.ov_stop_sector = ULLONG_MAX;
4083         if (info->attrs[DRBD_NLA_START_OV_PARMS]) {
4084                 int err = start_ov_parms_from_attrs(&parms, info);
4085                 if (err) {
4086                         retcode = ERR_MANDATORY_TAG;
4087                         drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
4088                         goto out;
4089                 }
4090         }
4091         mutex_lock(&adm_ctx.resource->adm_mutex);
4092
4093         /* w_make_ov_request expects position to be aligned */
4094         device->ov_start_sector = parms.ov_start_sector & ~(BM_SECT_PER_BIT-1);
4095         device->ov_stop_sector = parms.ov_stop_sector;
4096
4097         /* If there is still bitmap IO pending, e.g. previous resync or verify
4098          * just being finished, wait for it before requesting a new resync. */
4099         drbd_suspend_io(device);
4100         wait_event(device->misc_wait, !test_bit(BITMAP_IO, &device->flags));
4101         retcode = drbd_request_state(device, NS(conn, C_VERIFY_S));
4102         drbd_resume_io(device);
4103
4104         mutex_unlock(&adm_ctx.resource->adm_mutex);
4105 out:
4106         drbd_adm_finish(&adm_ctx, info, retcode);
4107         return 0;
4108 }
4109
4110
4111 int drbd_adm_new_c_uuid(struct sk_buff *skb, struct genl_info *info)
4112 {
4113         struct drbd_config_context adm_ctx;
4114         struct drbd_device *device;
4115         enum drbd_ret_code retcode;
4116         int skip_initial_sync = 0;
4117         int err;
4118         struct new_c_uuid_parms args;
4119
4120         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
4121         if (!adm_ctx.reply_skb)
4122                 return retcode;
4123         if (retcode != NO_ERROR)
4124                 goto out_nolock;
4125
4126         device = adm_ctx.device;
4127         memset(&args, 0, sizeof(args));
4128         if (info->attrs[DRBD_NLA_NEW_C_UUID_PARMS]) {
4129                 err = new_c_uuid_parms_from_attrs(&args, info);
4130                 if (err) {
4131                         retcode = ERR_MANDATORY_TAG;
4132                         drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
4133                         goto out_nolock;
4134                 }
4135         }
4136
4137         mutex_lock(&adm_ctx.resource->adm_mutex);
4138         mutex_lock(device->state_mutex); /* Protects us against serialized state changes. */
4139
4140         if (!get_ldev(device)) {
4141                 retcode = ERR_NO_DISK;
4142                 goto out;
4143         }
4144
4145         /* this is "skip initial sync", assume to be clean */
4146         if (device->state.conn == C_CONNECTED &&
4147             first_peer_device(device)->connection->agreed_pro_version >= 90 &&
4148             device->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED && args.clear_bm) {
4149                 drbd_info(device, "Preparing to skip initial sync\n");
4150                 skip_initial_sync = 1;
4151         } else if (device->state.conn != C_STANDALONE) {
4152                 retcode = ERR_CONNECTED;
4153                 goto out_dec;
4154         }
4155
4156         drbd_uuid_set(device, UI_BITMAP, 0); /* Rotate UI_BITMAP to History 1, etc... */
4157         drbd_uuid_new_current(device); /* New current, previous to UI_BITMAP */
4158
4159         if (args.clear_bm) {
4160                 err = drbd_bitmap_io(device, &drbd_bmio_clear_n_write,
4161                         "clear_n_write from new_c_uuid", BM_LOCKED_MASK, NULL);
4162                 if (err) {
4163                         drbd_err(device, "Writing bitmap failed with %d\n", err);
4164                         retcode = ERR_IO_MD_DISK;
4165                 }
4166                 if (skip_initial_sync) {
4167                         drbd_send_uuids_skip_initial_sync(first_peer_device(device));
4168                         _drbd_uuid_set(device, UI_BITMAP, 0);
4169                         drbd_print_uuids(device, "cleared bitmap UUID");
4170                         spin_lock_irq(&device->resource->req_lock);
4171                         _drbd_set_state(_NS2(device, disk, D_UP_TO_DATE, pdsk, D_UP_TO_DATE),
4172                                         CS_VERBOSE, NULL);
4173                         spin_unlock_irq(&device->resource->req_lock);
4174                 }
4175         }
4176
4177         drbd_md_sync(device);
4178 out_dec:
4179         put_ldev(device);
4180 out:
4181         mutex_unlock(device->state_mutex);
4182         mutex_unlock(&adm_ctx.resource->adm_mutex);
4183 out_nolock:
4184         drbd_adm_finish(&adm_ctx, info, retcode);
4185         return 0;
4186 }
4187
4188 static enum drbd_ret_code
4189 drbd_check_resource_name(struct drbd_config_context *adm_ctx)
4190 {
4191         const char *name = adm_ctx->resource_name;
4192         if (!name || !name[0]) {
4193                 drbd_msg_put_info(adm_ctx->reply_skb, "resource name missing");
4194                 return ERR_MANDATORY_TAG;
4195         }
4196         /* if we want to use these in sysfs/configfs/debugfs some day,
4197          * we must not allow slashes */
4198         if (strchr(name, '/')) {
4199                 drbd_msg_put_info(adm_ctx->reply_skb, "invalid resource name");
4200                 return ERR_INVALID_REQUEST;
4201         }
4202         return NO_ERROR;
4203 }
4204
4205 static void resource_to_info(struct resource_info *info,
4206                              struct drbd_resource *resource)
4207 {
4208         info->res_role = conn_highest_role(first_connection(resource));
4209         info->res_susp = resource->susp;
4210         info->res_susp_nod = resource->susp_nod;
4211         info->res_susp_fen = resource->susp_fen;
4212 }
4213
4214 int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info)
4215 {
4216         struct drbd_connection *connection;
4217         struct drbd_config_context adm_ctx;
4218         enum drbd_ret_code retcode;
4219         struct res_opts res_opts;
4220         int err;
4221
4222         retcode = drbd_adm_prepare(&adm_ctx, skb, info, 0);
4223         if (!adm_ctx.reply_skb)
4224                 return retcode;
4225         if (retcode != NO_ERROR)
4226                 goto out;
4227
4228         set_res_opts_defaults(&res_opts);
4229         err = res_opts_from_attrs(&res_opts, info);
4230         if (err && err != -ENOMSG) {
4231                 retcode = ERR_MANDATORY_TAG;
4232                 drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
4233                 goto out;
4234         }
4235
4236         retcode = drbd_check_resource_name(&adm_ctx);
4237         if (retcode != NO_ERROR)
4238                 goto out;
4239
4240         if (adm_ctx.resource) {
4241                 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL) {
4242                         retcode = ERR_INVALID_REQUEST;
4243                         drbd_msg_put_info(adm_ctx.reply_skb, "resource exists");
4244                 }
4245                 /* else: still NO_ERROR */
4246                 goto out;
4247         }
4248
4249         /* not yet safe for genl_family.parallel_ops */
4250         mutex_lock(&resources_mutex);
4251         connection = conn_create(adm_ctx.resource_name, &res_opts);
4252         mutex_unlock(&resources_mutex);
4253
4254         if (connection) {
4255                 struct resource_info resource_info;
4256
4257                 mutex_lock(&notification_mutex);
4258                 resource_to_info(&resource_info, connection->resource);
4259                 notify_resource_state(NULL, 0, connection->resource,
4260                                       &resource_info, NOTIFY_CREATE);
4261                 mutex_unlock(&notification_mutex);
4262         } else
4263                 retcode = ERR_NOMEM;
4264
4265 out:
4266         drbd_adm_finish(&adm_ctx, info, retcode);
4267         return 0;
4268 }
4269
4270 static void device_to_info(struct device_info *info,
4271                            struct drbd_device *device)
4272 {
4273         info->dev_disk_state = device->state.disk;
4274 }
4275
4276
4277 int drbd_adm_new_minor(struct sk_buff *skb, struct genl_info *info)
4278 {
4279         struct drbd_config_context adm_ctx;
4280         struct drbd_genlmsghdr *dh = genl_info_userhdr(info);
4281         enum drbd_ret_code retcode;
4282
4283         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_RESOURCE);
4284         if (!adm_ctx.reply_skb)
4285                 return retcode;
4286         if (retcode != NO_ERROR)
4287                 goto out;
4288
4289         if (dh->minor > MINORMASK) {
4290                 drbd_msg_put_info(adm_ctx.reply_skb, "requested minor out of range");
4291                 retcode = ERR_INVALID_REQUEST;
4292                 goto out;
4293         }
4294         if (adm_ctx.volume > DRBD_VOLUME_MAX) {
4295                 drbd_msg_put_info(adm_ctx.reply_skb, "requested volume id out of range");
4296                 retcode = ERR_INVALID_REQUEST;
4297                 goto out;
4298         }
4299
4300         /* drbd_adm_prepare made sure already
4301          * that first_peer_device(device)->connection and device->vnr match the request. */
4302         if (adm_ctx.device) {
4303                 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
4304                         retcode = ERR_MINOR_OR_VOLUME_EXISTS;
4305                 /* else: still NO_ERROR */
4306                 goto out;
4307         }
4308
4309         mutex_lock(&adm_ctx.resource->adm_mutex);
4310         retcode = drbd_create_device(&adm_ctx, dh->minor);
4311         if (retcode == NO_ERROR) {
4312                 struct drbd_device *device;
4313                 struct drbd_peer_device *peer_device;
4314                 struct device_info info;
4315                 unsigned int peer_devices = 0;
4316                 enum drbd_notification_type flags;
4317
4318                 device = minor_to_device(dh->minor);
4319                 for_each_peer_device(peer_device, device) {
4320                         if (!has_net_conf(peer_device->connection))
4321                                 continue;
4322                         peer_devices++;
4323                 }
4324
4325                 device_to_info(&info, device);
4326                 mutex_lock(&notification_mutex);
4327                 flags = (peer_devices--) ? NOTIFY_CONTINUES : 0;
4328                 notify_device_state(NULL, 0, device, &info, NOTIFY_CREATE | flags);
4329                 for_each_peer_device(peer_device, device) {
4330                         struct peer_device_info peer_device_info;
4331
4332                         if (!has_net_conf(peer_device->connection))
4333                                 continue;
4334                         peer_device_to_info(&peer_device_info, peer_device);
4335                         flags = (peer_devices--) ? NOTIFY_CONTINUES : 0;
4336                         notify_peer_device_state(NULL, 0, peer_device, &peer_device_info,
4337                                                  NOTIFY_CREATE | flags);
4338                 }
4339                 mutex_unlock(&notification_mutex);
4340         }
4341         mutex_unlock(&adm_ctx.resource->adm_mutex);
4342 out:
4343         drbd_adm_finish(&adm_ctx, info, retcode);
4344         return 0;
4345 }
4346
4347 static enum drbd_ret_code adm_del_minor(struct drbd_device *device)
4348 {
4349         struct drbd_peer_device *peer_device;
4350
4351         if (device->state.disk == D_DISKLESS &&
4352             /* no need to be device->state.conn == C_STANDALONE &&
4353              * we may want to delete a minor from a live replication group.
4354              */
4355             device->state.role == R_SECONDARY) {
4356                 struct drbd_connection *connection =
4357                         first_connection(device->resource);
4358
4359                 _drbd_request_state(device, NS(conn, C_WF_REPORT_PARAMS),
4360                                     CS_VERBOSE + CS_WAIT_COMPLETE);
4361
4362                 /* If the state engine hasn't stopped the sender thread yet, we
4363                  * need to flush the sender work queue before generating the
4364                  * DESTROY events here. */
4365                 if (get_t_state(&connection->worker) == RUNNING)
4366                         drbd_flush_workqueue(&connection->sender_work);
4367
4368                 mutex_lock(&notification_mutex);
4369                 for_each_peer_device(peer_device, device) {
4370                         if (!has_net_conf(peer_device->connection))
4371                                 continue;
4372                         notify_peer_device_state(NULL, 0, peer_device, NULL,
4373                                                  NOTIFY_DESTROY | NOTIFY_CONTINUES);
4374                 }
4375                 notify_device_state(NULL, 0, device, NULL, NOTIFY_DESTROY);
4376                 mutex_unlock(&notification_mutex);
4377
4378                 drbd_delete_device(device);
4379                 return NO_ERROR;
4380         } else
4381                 return ERR_MINOR_CONFIGURED;
4382 }
4383
4384 int drbd_adm_del_minor(struct sk_buff *skb, struct genl_info *info)
4385 {
4386         struct drbd_config_context adm_ctx;
4387         enum drbd_ret_code retcode;
4388
4389         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
4390         if (!adm_ctx.reply_skb)
4391                 return retcode;
4392         if (retcode != NO_ERROR)
4393                 goto out;
4394
4395         mutex_lock(&adm_ctx.resource->adm_mutex);
4396         retcode = adm_del_minor(adm_ctx.device);
4397         mutex_unlock(&adm_ctx.resource->adm_mutex);
4398 out:
4399         drbd_adm_finish(&adm_ctx, info, retcode);
4400         return 0;
4401 }
4402
4403 static int adm_del_resource(struct drbd_resource *resource)
4404 {
4405         struct drbd_connection *connection;
4406
4407         for_each_connection(connection, resource) {
4408                 if (connection->cstate > C_STANDALONE)
4409                         return ERR_NET_CONFIGURED;
4410         }
4411         if (!idr_is_empty(&resource->devices))
4412                 return ERR_RES_IN_USE;
4413
4414         /* The state engine has stopped the sender thread, so we don't
4415          * need to flush the sender work queue before generating the
4416          * DESTROY event here. */
4417         mutex_lock(&notification_mutex);
4418         notify_resource_state(NULL, 0, resource, NULL, NOTIFY_DESTROY);
4419         mutex_unlock(&notification_mutex);
4420
4421         mutex_lock(&resources_mutex);
4422         list_del_rcu(&resource->resources);
4423         mutex_unlock(&resources_mutex);
4424         /* Make sure all threads have actually stopped: state handling only
4425          * does drbd_thread_stop_nowait(). */
4426         list_for_each_entry(connection, &resource->connections, connections)
4427                 drbd_thread_stop(&connection->worker);
4428         synchronize_rcu();
4429         drbd_free_resource(resource);
4430         return NO_ERROR;
4431 }
4432
4433 int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
4434 {
4435         struct drbd_config_context adm_ctx;
4436         struct drbd_resource *resource;
4437         struct drbd_connection *connection;
4438         struct drbd_device *device;
4439         int retcode; /* enum drbd_ret_code rsp. enum drbd_state_rv */
4440         unsigned i;
4441
4442         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_RESOURCE);
4443         if (!adm_ctx.reply_skb)
4444                 return retcode;
4445         if (retcode != NO_ERROR)
4446                 goto finish;
4447
4448         resource = adm_ctx.resource;
4449         mutex_lock(&resource->adm_mutex);
4450         /* demote */
4451         for_each_connection(connection, resource) {
4452                 struct drbd_peer_device *peer_device;
4453
4454                 idr_for_each_entry(&connection->peer_devices, peer_device, i) {
4455                         retcode = drbd_set_role(peer_device->device, R_SECONDARY, 0);
4456                         if (retcode < SS_SUCCESS) {
4457                                 drbd_msg_put_info(adm_ctx.reply_skb, "failed to demote");
4458                                 goto out;
4459                         }
4460                 }
4461
4462                 retcode = conn_try_disconnect(connection, 0);
4463                 if (retcode < SS_SUCCESS) {
4464                         drbd_msg_put_info(adm_ctx.reply_skb, "failed to disconnect");
4465                         goto out;
4466                 }
4467         }
4468
4469         /* detach */
4470         idr_for_each_entry(&resource->devices, device, i) {
4471                 retcode = adm_detach(device, 0);
4472                 if (retcode < SS_SUCCESS || retcode > NO_ERROR) {
4473                         drbd_msg_put_info(adm_ctx.reply_skb, "failed to detach");
4474                         goto out;
4475                 }
4476         }
4477
4478         /* delete volumes */
4479         idr_for_each_entry(&resource->devices, device, i) {
4480                 retcode = adm_del_minor(device);
4481                 if (retcode != NO_ERROR) {
4482                         /* "can not happen" */
4483                         drbd_msg_put_info(adm_ctx.reply_skb, "failed to delete volume");
4484                         goto out;
4485                 }
4486         }
4487
4488         retcode = adm_del_resource(resource);
4489 out:
4490         mutex_unlock(&resource->adm_mutex);
4491 finish:
4492         drbd_adm_finish(&adm_ctx, info, retcode);
4493         return 0;
4494 }
4495
4496 int drbd_adm_del_resource(struct sk_buff *skb, struct genl_info *info)
4497 {
4498         struct drbd_config_context adm_ctx;
4499         struct drbd_resource *resource;
4500         enum drbd_ret_code retcode;
4501
4502         retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_RESOURCE);
4503         if (!adm_ctx.reply_skb)
4504                 return retcode;
4505         if (retcode != NO_ERROR)
4506                 goto finish;
4507         resource = adm_ctx.resource;
4508
4509         mutex_lock(&resource->adm_mutex);
4510         retcode = adm_del_resource(resource);
4511         mutex_unlock(&resource->adm_mutex);
4512 finish:
4513         drbd_adm_finish(&adm_ctx, info, retcode);
4514         return 0;
4515 }
4516
4517 void drbd_bcast_event(struct drbd_device *device, const struct sib_info *sib)
4518 {
4519         struct sk_buff *msg;
4520         struct drbd_genlmsghdr *d_out;
4521         unsigned seq;
4522         int err = -ENOMEM;
4523
4524         seq = atomic_inc_return(&drbd_genl_seq);
4525         msg = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO);
4526         if (!msg)
4527                 goto failed;
4528
4529         err = -EMSGSIZE;
4530         d_out = genlmsg_put(msg, 0, seq, &drbd_genl_family, 0, DRBD_EVENT);
4531         if (!d_out) /* cannot happen, but anyways. */
4532                 goto nla_put_failure;
4533         d_out->minor = device_to_minor(device);
4534         d_out->ret_code = NO_ERROR;
4535
4536         if (nla_put_status_info(msg, device, sib))
4537                 goto nla_put_failure;
4538         genlmsg_end(msg, d_out);
4539         err = drbd_genl_multicast_events(msg, GFP_NOWAIT);
4540         /* msg has been consumed or freed in netlink_broadcast() */
4541         if (err && err != -ESRCH)
4542                 goto failed;
4543
4544         return;
4545
4546 nla_put_failure:
4547         nlmsg_free(msg);
4548 failed:
4549         drbd_err(device, "Error %d while broadcasting event. "
4550                         "Event seq:%u sib_reason:%u\n",
4551                         err, seq, sib->sib_reason);
4552 }
4553
4554 static int nla_put_notification_header(struct sk_buff *msg,
4555                                        enum drbd_notification_type type)
4556 {
4557         struct drbd_notification_header nh = {
4558                 .nh_type = type,
4559         };
4560
4561         return drbd_notification_header_to_skb(msg, &nh, true);
4562 }
4563
4564 int notify_resource_state(struct sk_buff *skb,
4565                            unsigned int seq,
4566                            struct drbd_resource *resource,
4567                            struct resource_info *resource_info,
4568                            enum drbd_notification_type type)
4569 {
4570         struct resource_statistics resource_statistics;
4571         struct drbd_genlmsghdr *dh;
4572         bool multicast = false;
4573         int err;
4574
4575         if (!skb) {
4576                 seq = atomic_inc_return(&notify_genl_seq);
4577                 skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO);
4578                 err = -ENOMEM;
4579                 if (!skb)
4580                         goto failed;
4581                 multicast = true;
4582         }
4583
4584         err = -EMSGSIZE;
4585         dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_RESOURCE_STATE);
4586         if (!dh)
4587                 goto nla_put_failure;
4588         dh->minor = -1U;
4589         dh->ret_code = NO_ERROR;
4590         if (nla_put_drbd_cfg_context(skb, resource, NULL, NULL) ||
4591             nla_put_notification_header(skb, type) ||
4592             ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY &&
4593              resource_info_to_skb(skb, resource_info, true)))
4594                 goto nla_put_failure;
4595         resource_statistics.res_stat_write_ordering = resource->write_ordering;
4596         err = resource_statistics_to_skb(skb, &resource_statistics, !capable(CAP_SYS_ADMIN));
4597         if (err)
4598                 goto nla_put_failure;
4599         genlmsg_end(skb, dh);
4600         if (multicast) {
4601                 err = drbd_genl_multicast_events(skb, GFP_NOWAIT);
4602                 /* skb has been consumed or freed in netlink_broadcast() */
4603                 if (err && err != -ESRCH)
4604                         goto failed;
4605         }
4606         return 0;
4607
4608 nla_put_failure:
4609         nlmsg_free(skb);
4610 failed:
4611         drbd_err(resource, "Error %d while broadcasting event. Event seq:%u\n",
4612                         err, seq);
4613         return err;
4614 }
4615
4616 int notify_device_state(struct sk_buff *skb,
4617                          unsigned int seq,
4618                          struct drbd_device *device,
4619                          struct device_info *device_info,
4620                          enum drbd_notification_type type)
4621 {
4622         struct device_statistics device_statistics;
4623         struct drbd_genlmsghdr *dh;
4624         bool multicast = false;
4625         int err;
4626
4627         if (!skb) {
4628                 seq = atomic_inc_return(&notify_genl_seq);
4629                 skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO);
4630                 err = -ENOMEM;
4631                 if (!skb)
4632                         goto failed;
4633                 multicast = true;
4634         }
4635
4636         err = -EMSGSIZE;
4637         dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_DEVICE_STATE);
4638         if (!dh)
4639                 goto nla_put_failure;
4640         dh->minor = device->minor;
4641         dh->ret_code = NO_ERROR;
4642         if (nla_put_drbd_cfg_context(skb, device->resource, NULL, device) ||
4643             nla_put_notification_header(skb, type) ||
4644             ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY &&
4645              device_info_to_skb(skb, device_info, true)))
4646                 goto nla_put_failure;
4647         device_to_statistics(&device_statistics, device);
4648         device_statistics_to_skb(skb, &device_statistics, !capable(CAP_SYS_ADMIN));
4649         genlmsg_end(skb, dh);
4650         if (multicast) {
4651                 err = drbd_genl_multicast_events(skb, GFP_NOWAIT);
4652                 /* skb has been consumed or freed in netlink_broadcast() */
4653                 if (err && err != -ESRCH)
4654                         goto failed;
4655         }
4656         return 0;
4657
4658 nla_put_failure:
4659         nlmsg_free(skb);
4660 failed:
4661         drbd_err(device, "Error %d while broadcasting event. Event seq:%u\n",
4662                  err, seq);
4663         return err;
4664 }
4665
4666 int notify_connection_state(struct sk_buff *skb,
4667                              unsigned int seq,
4668                              struct drbd_connection *connection,
4669                              struct connection_info *connection_info,
4670                              enum drbd_notification_type type)
4671 {
4672         struct connection_statistics connection_statistics;
4673         struct drbd_genlmsghdr *dh;
4674         bool multicast = false;
4675         int err;
4676
4677         if (!skb) {
4678                 seq = atomic_inc_return(&notify_genl_seq);
4679                 skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO);
4680                 err = -ENOMEM;
4681                 if (!skb)
4682                         goto failed;
4683                 multicast = true;
4684         }
4685
4686         err = -EMSGSIZE;
4687         dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_CONNECTION_STATE);
4688         if (!dh)
4689                 goto nla_put_failure;
4690         dh->minor = -1U;
4691         dh->ret_code = NO_ERROR;
4692         if (nla_put_drbd_cfg_context(skb, connection->resource, connection, NULL) ||
4693             nla_put_notification_header(skb, type) ||
4694             ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY &&
4695              connection_info_to_skb(skb, connection_info, true)))
4696                 goto nla_put_failure;
4697         connection_statistics.conn_congested = test_bit(NET_CONGESTED, &connection->flags);
4698         connection_statistics_to_skb(skb, &connection_statistics, !capable(CAP_SYS_ADMIN));
4699         genlmsg_end(skb, dh);
4700         if (multicast) {
4701                 err = drbd_genl_multicast_events(skb, GFP_NOWAIT);
4702                 /* skb has been consumed or freed in netlink_broadcast() */
4703                 if (err && err != -ESRCH)
4704                         goto failed;
4705         }
4706         return 0;
4707
4708 nla_put_failure:
4709         nlmsg_free(skb);
4710 failed:
4711         drbd_err(connection, "Error %d while broadcasting event. Event seq:%u\n",
4712                  err, seq);
4713         return err;
4714 }
4715
4716 int notify_peer_device_state(struct sk_buff *skb,
4717                               unsigned int seq,
4718                               struct drbd_peer_device *peer_device,
4719                               struct peer_device_info *peer_device_info,
4720                               enum drbd_notification_type type)
4721 {
4722         struct peer_device_statistics peer_device_statistics;
4723         struct drbd_resource *resource = peer_device->device->resource;
4724         struct drbd_genlmsghdr *dh;
4725         bool multicast = false;
4726         int err;
4727
4728         if (!skb) {
4729                 seq = atomic_inc_return(&notify_genl_seq);
4730                 skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO);
4731                 err = -ENOMEM;
4732                 if (!skb)
4733                         goto failed;
4734                 multicast = true;
4735         }
4736
4737         err = -EMSGSIZE;
4738         dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_PEER_DEVICE_STATE);
4739         if (!dh)
4740                 goto nla_put_failure;
4741         dh->minor = -1U;
4742         dh->ret_code = NO_ERROR;
4743         if (nla_put_drbd_cfg_context(skb, resource, peer_device->connection, peer_device->device) ||
4744             nla_put_notification_header(skb, type) ||
4745             ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY &&
4746              peer_device_info_to_skb(skb, peer_device_info, true)))
4747                 goto nla_put_failure;
4748         peer_device_to_statistics(&peer_device_statistics, peer_device);
4749         peer_device_statistics_to_skb(skb, &peer_device_statistics, !capable(CAP_SYS_ADMIN));
4750         genlmsg_end(skb, dh);
4751         if (multicast) {
4752                 err = drbd_genl_multicast_events(skb, GFP_NOWAIT);
4753                 /* skb has been consumed or freed in netlink_broadcast() */
4754                 if (err && err != -ESRCH)
4755                         goto failed;
4756         }
4757         return 0;
4758
4759 nla_put_failure:
4760         nlmsg_free(skb);
4761 failed:
4762         drbd_err(peer_device, "Error %d while broadcasting event. Event seq:%u\n",
4763                  err, seq);
4764         return err;
4765 }
4766
4767 void notify_helper(enum drbd_notification_type type,
4768                    struct drbd_device *device, struct drbd_connection *connection,
4769                    const char *name, int status)
4770 {
4771         struct drbd_resource *resource = device ? device->resource : connection->resource;
4772         struct drbd_helper_info helper_info;
4773         unsigned int seq = atomic_inc_return(&notify_genl_seq);
4774         struct sk_buff *skb = NULL;
4775         struct drbd_genlmsghdr *dh;
4776         int err;
4777
4778         strscpy(helper_info.helper_name, name, sizeof(helper_info.helper_name));
4779         helper_info.helper_name_len = min(strlen(name), sizeof(helper_info.helper_name));
4780         helper_info.helper_status = status;
4781
4782         skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO);
4783         err = -ENOMEM;
4784         if (!skb)
4785                 goto fail;
4786
4787         err = -EMSGSIZE;
4788         dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_HELPER);
4789         if (!dh)
4790                 goto fail;
4791         dh->minor = device ? device->minor : -1;
4792         dh->ret_code = NO_ERROR;
4793         mutex_lock(&notification_mutex);
4794         if (nla_put_drbd_cfg_context(skb, resource, connection, device) ||
4795             nla_put_notification_header(skb, type) ||
4796             drbd_helper_info_to_skb(skb, &helper_info, true))
4797                 goto unlock_fail;
4798         genlmsg_end(skb, dh);
4799         err = drbd_genl_multicast_events(skb, GFP_NOWAIT);
4800         skb = NULL;
4801         /* skb has been consumed or freed in netlink_broadcast() */
4802         if (err && err != -ESRCH)
4803                 goto unlock_fail;
4804         mutex_unlock(&notification_mutex);
4805         return;
4806
4807 unlock_fail:
4808         mutex_unlock(&notification_mutex);
4809 fail:
4810         nlmsg_free(skb);
4811         drbd_err(resource, "Error %d while broadcasting event. Event seq:%u\n",
4812                  err, seq);
4813 }
4814
4815 static int notify_initial_state_done(struct sk_buff *skb, unsigned int seq)
4816 {
4817         struct drbd_genlmsghdr *dh;
4818         int err;
4819
4820         err = -EMSGSIZE;
4821         dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_INITIAL_STATE_DONE);
4822         if (!dh)
4823                 goto nla_put_failure;
4824         dh->minor = -1U;
4825         dh->ret_code = NO_ERROR;
4826         if (nla_put_notification_header(skb, NOTIFY_EXISTS))
4827                 goto nla_put_failure;
4828         genlmsg_end(skb, dh);
4829         return 0;
4830
4831 nla_put_failure:
4832         nlmsg_free(skb);
4833         pr_err("Error %d sending event. Event seq:%u\n", err, seq);
4834         return err;
4835 }
4836
4837 static void free_state_changes(struct list_head *list)
4838 {
4839         while (!list_empty(list)) {
4840                 struct drbd_state_change *state_change =
4841                         list_first_entry(list, struct drbd_state_change, list);
4842                 list_del(&state_change->list);
4843                 forget_state_change(state_change);
4844         }
4845 }
4846
4847 static unsigned int notifications_for_state_change(struct drbd_state_change *state_change)
4848 {
4849         return 1 +
4850                state_change->n_connections +
4851                state_change->n_devices +
4852                state_change->n_devices * state_change->n_connections;
4853 }
4854
4855 static int get_initial_state(struct sk_buff *skb, struct netlink_callback *cb)
4856 {
4857         struct drbd_state_change *state_change = (struct drbd_state_change *)cb->args[0];
4858         unsigned int seq = cb->args[2];
4859         unsigned int n;
4860         enum drbd_notification_type flags = 0;
4861         int err = 0;
4862
4863         /* There is no need for taking notification_mutex here: it doesn't
4864            matter if the initial state events mix with later state chage
4865            events; we can always tell the events apart by the NOTIFY_EXISTS
4866            flag. */
4867
4868         cb->args[5]--;
4869         if (cb->args[5] == 1) {
4870                 err = notify_initial_state_done(skb, seq);
4871                 goto out;
4872         }
4873         n = cb->args[4]++;
4874         if (cb->args[4] < cb->args[3])
4875                 flags |= NOTIFY_CONTINUES;
4876         if (n < 1) {
4877                 err = notify_resource_state_change(skb, seq, state_change->resource,
4878                                              NOTIFY_EXISTS | flags);
4879                 goto next;
4880         }
4881         n--;
4882         if (n < state_change->n_connections) {
4883                 err = notify_connection_state_change(skb, seq, &state_change->connections[n],
4884                                                NOTIFY_EXISTS | flags);
4885                 goto next;
4886         }
4887         n -= state_change->n_connections;
4888         if (n < state_change->n_devices) {
4889                 err = notify_device_state_change(skb, seq, &state_change->devices[n],
4890                                            NOTIFY_EXISTS | flags);
4891                 goto next;
4892         }
4893         n -= state_change->n_devices;
4894         if (n < state_change->n_devices * state_change->n_connections) {
4895                 err = notify_peer_device_state_change(skb, seq, &state_change->peer_devices[n],
4896                                                 NOTIFY_EXISTS | flags);
4897                 goto next;
4898         }
4899
4900 next:
4901         if (cb->args[4] == cb->args[3]) {
4902                 struct drbd_state_change *next_state_change =
4903                         list_entry(state_change->list.next,
4904                                    struct drbd_state_change, list);
4905                 cb->args[0] = (long)next_state_change;
4906                 cb->args[3] = notifications_for_state_change(next_state_change);
4907                 cb->args[4] = 0;
4908         }
4909 out:
4910         if (err)
4911                 return err;
4912         else
4913                 return skb->len;
4914 }
4915
4916 int drbd_adm_get_initial_state(struct sk_buff *skb, struct netlink_callback *cb)
4917 {
4918         struct drbd_resource *resource;
4919         LIST_HEAD(head);
4920
4921         if (cb->args[5] >= 1) {
4922                 if (cb->args[5] > 1)
4923                         return get_initial_state(skb, cb);
4924                 if (cb->args[0]) {
4925                         struct drbd_state_change *state_change =
4926                                 (struct drbd_state_change *)cb->args[0];
4927
4928                         /* connect list to head */
4929                         list_add(&head, &state_change->list);
4930                         free_state_changes(&head);
4931                 }
4932                 return 0;
4933         }
4934
4935         cb->args[5] = 2;  /* number of iterations */
4936         mutex_lock(&resources_mutex);
4937         for_each_resource(resource, &drbd_resources) {
4938                 struct drbd_state_change *state_change;
4939
4940                 state_change = remember_old_state(resource, GFP_KERNEL);
4941                 if (!state_change) {
4942                         if (!list_empty(&head))
4943                                 free_state_changes(&head);
4944                         mutex_unlock(&resources_mutex);
4945                         return -ENOMEM;
4946                 }
4947                 copy_old_to_new_state_change(state_change);
4948                 list_add_tail(&state_change->list, &head);
4949                 cb->args[5] += notifications_for_state_change(state_change);
4950         }
4951         mutex_unlock(&resources_mutex);
4952
4953         if (!list_empty(&head)) {
4954                 struct drbd_state_change *state_change =
4955                         list_entry(head.next, struct drbd_state_change, list);
4956                 cb->args[0] = (long)state_change;
4957                 cb->args[3] = notifications_for_state_change(state_change);
4958                 list_del(&head);  /* detach list from head */
4959         }
4960
4961         cb->args[2] = cb->nlh->nlmsg_seq;
4962         return get_initial_state(skb, cb);
4963 }