drivers/block/drbd/drbd_nl.c

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