SAFE public projects git trees. - safe/jmp/linux-2.6/blob - fs/dlm/rcom.c

   1 /******************************************************************************
   2 *******************************************************************************
   3 **
   4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
   5 **  Copyright (C) 2005 Red Hat, Inc.  All rights reserved.
   6 **
   7 **  This copyrighted material is made available to anyone wishing to use,
   8 **  modify, copy, or redistribute it subject to the terms and conditions
   9 **  of the GNU General Public License v.2.
  10 **
  11 *******************************************************************************
  12 ******************************************************************************/
  13
  14 #include "dlm_internal.h"
  15 #include "lockspace.h"
  16 #include "member.h"
  17 #include "lowcomms.h"
  18 #include "midcomms.h"
  19 #include "rcom.h"
  20 #include "recover.h"
  21 #include "dir.h"
  22 #include "config.h"
  23 #include "memory.h"
  24 #include "lock.h"
  25 #include "util.h"
  26
  27
  28 static int rcom_response(struct dlm_ls *ls)
  29 {
  30         return test_bit(LSFL_RCOM_READY, &ls->ls_flags);
  31 }
  32
  33 static int create_rcom(struct dlm_ls *ls, int to_nodeid, int type, int len,
  34                        struct dlm_rcom **rc_ret, struct dlm_mhandle **mh_ret)
  35 {
  36         struct dlm_rcom *rc;
  37         struct dlm_mhandle *mh;
  38         char *mb;
  39         int mb_len = sizeof(struct dlm_rcom) + len;
  40
  41         mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb);
  42         if (!mh) {
  43                 log_print("create_rcom to %d type %d len %d ENOBUFS",
  44                           to_nodeid, type, len);
  45                 return -ENOBUFS;
  46         }
  47         memset(mb, 0, mb_len);
  48
  49         rc = (struct dlm_rcom *) mb;
  50
  51         rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
  52         rc->rc_header.h_lockspace = ls->ls_global_id;
  53         rc->rc_header.h_nodeid = dlm_our_nodeid();
  54         rc->rc_header.h_length = mb_len;
  55         rc->rc_header.h_cmd = DLM_RCOM;
  56
  57         rc->rc_type = type;
  58
  59         spin_lock(&ls->ls_recover_lock);
  60         rc->rc_seq = ls->ls_recover_seq;
  61         spin_unlock(&ls->ls_recover_lock);
  62
  63         *mh_ret = mh;
  64         *rc_ret = rc;
  65         return 0;
  66 }
  67
  68 static void send_rcom(struct dlm_ls *ls, struct dlm_mhandle *mh,
  69                       struct dlm_rcom *rc)
  70 {
  71         dlm_rcom_out(rc);
  72         dlm_lowcomms_commit_buffer(mh);
  73 }
  74
  75 /* When replying to a status request, a node also sends back its
  76    configuration values.  The requesting node then checks that the remote
  77    node is configured the same way as itself. */
  78
  79 static void make_config(struct dlm_ls *ls, struct rcom_config *rf)
  80 {
  81         rf->rf_lvblen = ls->ls_lvblen;
  82         rf->rf_lsflags = ls->ls_exflags;
  83 }
  84
  85 static int check_config(struct dlm_ls *ls, struct rcom_config *rf, int nodeid)
  86 {
  87         if (rf->rf_lvblen != ls->ls_lvblen ||
  88             rf->rf_lsflags != ls->ls_exflags) {
  89                 log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x",
  90                           ls->ls_lvblen, ls->ls_exflags,
  91                           nodeid, rf->rf_lvblen, rf->rf_lsflags);
  92                 return -EINVAL;
  93         }
  94         return 0;
  95 }
  96
  97 static void allow_sync_reply(struct dlm_ls *ls, uint64_t *new_seq)
  98 {
  99         spin_lock(&ls->ls_rcom_spin);
 100         *new_seq = ++ls->ls_rcom_seq;
 101         set_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 102         spin_unlock(&ls->ls_rcom_spin);
 103 }
 104
 105 static void disallow_sync_reply(struct dlm_ls *ls)
 106 {
 107         spin_lock(&ls->ls_rcom_spin);
 108         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 109         clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
 110         spin_unlock(&ls->ls_rcom_spin);
 111 }
 112
 113 int dlm_rcom_status(struct dlm_ls *ls, int nodeid)
 114 {
 115         struct dlm_rcom *rc;
 116         struct dlm_mhandle *mh;
 117         int error = 0;
 118
 119         ls->ls_recover_nodeid = nodeid;
 120
 121         if (nodeid == dlm_our_nodeid()) {
 122                 rc = (struct dlm_rcom *) ls->ls_recover_buf;
 123                 rc->rc_result = dlm_recover_status(ls);
 124                 goto out;
 125         }
 126
 127         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh);
 128         if (error)
 129                 goto out;
 130
 131         allow_sync_reply(ls, &rc->rc_id);
 132         memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);
 133
 134         send_rcom(ls, mh, rc);
 135
 136         error = dlm_wait_function(ls, &rcom_response);
 137         disallow_sync_reply(ls);
 138         if (error)
 139                 goto out;
 140
 141         rc = (struct dlm_rcom *) ls->ls_recover_buf;
 142
 143         if (rc->rc_result == -ESRCH) {
 144                 /* we pretend the remote lockspace exists with 0 status */
 145                 log_debug(ls, "remote node %d not ready", nodeid);
 146                 rc->rc_result = 0;
 147         } else
 148                 error = check_config(ls, (struct rcom_config *) rc->rc_buf,
 149                                      nodeid);
 150         /* the caller looks at rc_result for the remote recovery status */
 151  out:
 152         return error;
 153 }
 154
 155 static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 156 {
 157         struct dlm_rcom *rc;
 158         struct dlm_mhandle *mh;
 159         int error, nodeid = rc_in->rc_header.h_nodeid;
 160
 161         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
 162                             sizeof(struct rcom_config), &rc, &mh);
 163         if (error)
 164                 return;
 165         rc->rc_id = rc_in->rc_id;
 166         rc->rc_seq_reply = rc_in->rc_seq;
 167         rc->rc_result = dlm_recover_status(ls);
 168         make_config(ls, (struct rcom_config *) rc->rc_buf);
 169
 170         send_rcom(ls, mh, rc);
 171 }
 172
 173 static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 174 {
 175         spin_lock(&ls->ls_rcom_spin);
 176         if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
 177             rc_in->rc_id != ls->ls_rcom_seq) {
 178                 log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
 179                           rc_in->rc_type, rc_in->rc_header.h_nodeid,
 180                           (unsigned long long)rc_in->rc_id,
 181                           (unsigned long long)ls->ls_rcom_seq);
 182                 goto out;
 183         }
 184         memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
 185         set_bit(LSFL_RCOM_READY, &ls->ls_flags);
 186         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 187         wake_up(&ls->ls_wait_general);
 188  out:
 189         spin_unlock(&ls->ls_rcom_spin);
 190 }
 191
 192 static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 193 {
 194         receive_sync_reply(ls, rc_in);
 195 }
 196
 197 int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
 198 {
 199         struct dlm_rcom *rc;
 200         struct dlm_mhandle *mh;
 201         int error = 0, len = sizeof(struct dlm_rcom);
 202
 203         ls->ls_recover_nodeid = nodeid;
 204
 205         if (nodeid == dlm_our_nodeid()) {
 206                 dlm_copy_master_names(ls, last_name, last_len,
 207                                       ls->ls_recover_buf + len,
 208                                       dlm_config.buffer_size - len, nodeid);
 209                 goto out;
 210         }
 211
 212         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
 213         if (error)
 214                 goto out;
 215         memcpy(rc->rc_buf, last_name, last_len);
 216
 217         allow_sync_reply(ls, &rc->rc_id);
 218         memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);
 219
 220         send_rcom(ls, mh, rc);
 221
 222         error = dlm_wait_function(ls, &rcom_response);
 223         disallow_sync_reply(ls);
 224  out:
 225         return error;
 226 }
 227
 228 static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 229 {
 230         struct dlm_rcom *rc;
 231         struct dlm_mhandle *mh;
 232         int error, inlen, outlen, nodeid;
 233
 234         nodeid = rc_in->rc_header.h_nodeid;
 235         inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 236         outlen = dlm_config.buffer_size - sizeof(struct dlm_rcom);
 237
 238         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
 239         if (error)
 240                 return;
 241         rc->rc_id = rc_in->rc_id;
 242         rc->rc_seq_reply = rc_in->rc_seq;
 243
 244         dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
 245                               nodeid);
 246         send_rcom(ls, mh, rc);
 247 }
 248
 249 static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 250 {
 251         receive_sync_reply(ls, rc_in);
 252 }
 253
 254 int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
 255 {
 256         struct dlm_rcom *rc;
 257         struct dlm_mhandle *mh;
 258         struct dlm_ls *ls = r->res_ls;
 259         int error;
 260
 261         error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
 262                             &rc, &mh);
 263         if (error)
 264                 goto out;
 265         memcpy(rc->rc_buf, r->res_name, r->res_length);
 266         rc->rc_id = (unsigned long) r;
 267
 268         send_rcom(ls, mh, rc);
 269  out:
 270         return error;
 271 }
 272
 273 static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 274 {
 275         struct dlm_rcom *rc;
 276         struct dlm_mhandle *mh;
 277         int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
 278         int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 279
 280         error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
 281         if (error)
 282                 return;
 283
 284         error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid);
 285         if (error)
 286                 ret_nodeid = error;
 287         rc->rc_result = ret_nodeid;
 288         rc->rc_id = rc_in->rc_id;
 289         rc->rc_seq_reply = rc_in->rc_seq;
 290
 291         send_rcom(ls, mh, rc);
 292 }
 293
 294 static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 295 {
 296         dlm_recover_master_reply(ls, rc_in);
 297 }
 298
 299 static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
 300                            struct rcom_lock *rl)
 301 {
 302         memset(rl, 0, sizeof(*rl));
 303
 304         rl->rl_ownpid = lkb->lkb_ownpid;
 305         rl->rl_lkid = lkb->lkb_id;
 306         rl->rl_exflags = lkb->lkb_exflags;
 307         rl->rl_flags = lkb->lkb_flags;
 308         rl->rl_lvbseq = lkb->lkb_lvbseq;
 309         rl->rl_rqmode = lkb->lkb_rqmode;
 310         rl->rl_grmode = lkb->lkb_grmode;
 311         rl->rl_status = lkb->lkb_status;
 312         rl->rl_wait_type = lkb->lkb_wait_type;
 313
 314         if (lkb->lkb_bastaddr)
 315                 rl->rl_asts |= AST_BAST;
 316         if (lkb->lkb_astaddr)
 317                 rl->rl_asts |= AST_COMP;
 318
 319         rl->rl_namelen = r->res_length;
 320         memcpy(rl->rl_name, r->res_name, r->res_length);
 321
 322         /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
 323            If so, receive_rcom_lock_args() won't take this copy. */
 324
 325         if (lkb->lkb_lvbptr)
 326                 memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
 327 }
 328
 329 int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
 330 {
 331         struct dlm_ls *ls = r->res_ls;
 332         struct dlm_rcom *rc;
 333         struct dlm_mhandle *mh;
 334         struct rcom_lock *rl;
 335         int error, len = sizeof(struct rcom_lock);
 336
 337         if (lkb->lkb_lvbptr)
 338                 len += ls->ls_lvblen;
 339
 340         error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
 341         if (error)
 342                 goto out;
 343
 344         rl = (struct rcom_lock *) rc->rc_buf;
 345         pack_rcom_lock(r, lkb, rl);
 346         rc->rc_id = (unsigned long) r;
 347
 348         send_rcom(ls, mh, rc);
 349  out:
 350         return error;
 351 }
 352
 353 static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 354 {
 355         struct dlm_rcom *rc;
 356         struct dlm_mhandle *mh;
 357         int error, nodeid = rc_in->rc_header.h_nodeid;
 358
 359         dlm_recover_master_copy(ls, rc_in);
 360
 361         error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
 362                             sizeof(struct rcom_lock), &rc, &mh);
 363         if (error)
 364                 return;
 365
 366         /* We send back the same rcom_lock struct we received, but
 367            dlm_recover_master_copy() has filled in rl_remid and rl_result */
 368
 369         memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
 370         rc->rc_id = rc_in->rc_id;
 371         rc->rc_seq_reply = rc_in->rc_seq;
 372
 373         send_rcom(ls, mh, rc);
 374 }
 375
 376 static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 377 {
 378         dlm_recover_process_copy(ls, rc_in);
 379 }
 380
 381 static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
 382 {
 383         struct dlm_rcom *rc;
 384         struct rcom_config *rf;
 385         struct dlm_mhandle *mh;
 386         char *mb;
 387         int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
 388
 389         mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb);
 390         if (!mh)
 391                 return -ENOBUFS;
 392         memset(mb, 0, mb_len);
 393
 394         rc = (struct dlm_rcom *) mb;
 395
 396         rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
 397         rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
 398         rc->rc_header.h_nodeid = dlm_our_nodeid();
 399         rc->rc_header.h_length = mb_len;
 400         rc->rc_header.h_cmd = DLM_RCOM;
 401
 402         rc->rc_type = DLM_RCOM_STATUS_REPLY;
 403         rc->rc_id = rc_in->rc_id;
 404         rc->rc_seq_reply = rc_in->rc_seq;
 405         rc->rc_result = -ESRCH;
 406
 407         rf = (struct rcom_config *) rc->rc_buf;
 408         rf->rf_lvblen = -1;
 409
 410         dlm_rcom_out(rc);
 411         dlm_lowcomms_commit_buffer(mh);
 412
 413         return 0;
 414 }
 415
 416 static int is_old_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
 417 {
 418         uint64_t seq;
 419         int rv = 0;
 420
 421         switch (rc->rc_type) {
 422         case DLM_RCOM_STATUS_REPLY:
 423         case DLM_RCOM_NAMES_REPLY:
 424         case DLM_RCOM_LOOKUP_REPLY:
 425         case DLM_RCOM_LOCK_REPLY:
 426                 spin_lock(&ls->ls_recover_lock);
 427                 seq = ls->ls_recover_seq;
 428                 spin_unlock(&ls->ls_recover_lock);
 429                 if (rc->rc_seq_reply != seq) {
 430                         log_error(ls, "ignoring old reply %x from %d "
 431                                       "seq_reply %llx expect %llx",
 432                                       rc->rc_type, rc->rc_header.h_nodeid,
 433                                       (unsigned long long)rc->rc_seq_reply,
 434                                       (unsigned long long)seq);
 435                         rv = 1;
 436                 }
 437         }
 438         return rv;
 439 }
 440
 441 /* Called by dlm_recvd; corresponds to dlm_receive_message() but special
 442    recovery-only comms are sent through here. */
 443
 444 void dlm_receive_rcom(struct dlm_header *hd, int nodeid)
 445 {
 446         struct dlm_rcom *rc = (struct dlm_rcom *) hd;
 447         struct dlm_ls *ls;
 448
 449         dlm_rcom_in(rc);
 450
 451         /* If the lockspace doesn't exist then still send a status message
 452            back; it's possible that it just doesn't have its global_id yet. */
 453
 454         ls = dlm_find_lockspace_global(hd->h_lockspace);
 455         if (!ls) {
 456                 log_print("lockspace %x from %d type %x not found",
 457                           hd->h_lockspace, nodeid, rc->rc_type);
 458                 if (rc->rc_type == DLM_RCOM_STATUS)
 459                         send_ls_not_ready(nodeid, rc);
 460                 return;
 461         }
 462
 463         if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
 464                 log_error(ls, "ignoring recovery message %x from %d",
 465                           rc->rc_type, nodeid);
 466                 goto out;
 467         }
 468
 469         if (is_old_reply(ls, rc))
 470                 goto out;
 471
 472         if (nodeid != rc->rc_header.h_nodeid) {
 473                 log_error(ls, "bad rcom nodeid %d from %d",
 474                           rc->rc_header.h_nodeid, nodeid);
 475                 goto out;
 476         }
 477
 478         switch (rc->rc_type) {
 479         case DLM_RCOM_STATUS:
 480                 receive_rcom_status(ls, rc);
 481                 break;
 482
 483         case DLM_RCOM_NAMES:
 484                 receive_rcom_names(ls, rc);
 485                 break;
 486
 487         case DLM_RCOM_LOOKUP:
 488                 receive_rcom_lookup(ls, rc);
 489                 break;
 490
 491         case DLM_RCOM_LOCK:
 492                 receive_rcom_lock(ls, rc);
 493                 break;
 494
 495         case DLM_RCOM_STATUS_REPLY:
 496                 receive_rcom_status_reply(ls, rc);
 497                 break;
 498
 499         case DLM_RCOM_NAMES_REPLY:
 500                 receive_rcom_names_reply(ls, rc);
 501                 break;
 502
 503         case DLM_RCOM_LOOKUP_REPLY:
 504                 receive_rcom_lookup_reply(ls, rc);
 505                 break;
 506
 507         case DLM_RCOM_LOCK_REPLY:
 508                 receive_rcom_lock_reply(ls, rc);
 509                 break;
 510
 511         default:
 512                 DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type););
 513         }
 514  out:
 515         dlm_put_lockspace(ls);
 516 }
 517