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) 2005-2008 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, ls->ls_allocation, &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 = cpu_to_le32(ls->ls_lvblen);
  82         rf->rf_lsflags = cpu_to_le32(ls->ls_exflags);
  83 }
  84
  85 static int check_config(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
  86 {
  87         struct rcom_config *rf = (struct rcom_config *) rc->rc_buf;
  88         size_t conf_size = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
  89
  90         if ((rc->rc_header.h_version & 0xFFFF0000) != DLM_HEADER_MAJOR) {
  91                 log_error(ls, "version mismatch: %x nodeid %d: %x",
  92                           DLM_HEADER_MAJOR | DLM_HEADER_MINOR, nodeid,
  93                           rc->rc_header.h_version);
  94                 return -EPROTO;
  95         }
  96
  97         if (rc->rc_header.h_length < conf_size) {
  98                 log_error(ls, "config too short: %d nodeid %d",
  99                           rc->rc_header.h_length, nodeid);
 100                 return -EPROTO;
 101         }
 102
 103         if (le32_to_cpu(rf->rf_lvblen) != ls->ls_lvblen ||
 104             le32_to_cpu(rf->rf_lsflags) != ls->ls_exflags) {
 105                 log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x",
 106                           ls->ls_lvblen, ls->ls_exflags, nodeid,
 107                           le32_to_cpu(rf->rf_lvblen),
 108                           le32_to_cpu(rf->rf_lsflags));
 109                 return -EPROTO;
 110         }
 111         return 0;
 112 }
 113
 114 static void allow_sync_reply(struct dlm_ls *ls, uint64_t *new_seq)
 115 {
 116         spin_lock(&ls->ls_rcom_spin);
 117         *new_seq = ++ls->ls_rcom_seq;
 118         set_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 119         spin_unlock(&ls->ls_rcom_spin);
 120 }
 121
 122 static void disallow_sync_reply(struct dlm_ls *ls)
 123 {
 124         spin_lock(&ls->ls_rcom_spin);
 125         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 126         clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
 127         spin_unlock(&ls->ls_rcom_spin);
 128 }
 129
 130 int dlm_rcom_status(struct dlm_ls *ls, int nodeid)
 131 {
 132         struct dlm_rcom *rc;
 133         struct dlm_mhandle *mh;
 134         int error = 0;
 135
 136         ls->ls_recover_nodeid = nodeid;
 137
 138         if (nodeid == dlm_our_nodeid()) {
 139                 rc = ls->ls_recover_buf;
 140                 rc->rc_result = dlm_recover_status(ls);
 141                 goto out;
 142         }
 143
 144         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh);
 145         if (error)
 146                 goto out;
 147
 148         allow_sync_reply(ls, &rc->rc_id);
 149         memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
 150
 151         send_rcom(ls, mh, rc);
 152
 153         error = dlm_wait_function(ls, &rcom_response);
 154         disallow_sync_reply(ls);
 155         if (error)
 156                 goto out;
 157
 158         rc = ls->ls_recover_buf;
 159
 160         if (rc->rc_result == -ESRCH) {
 161                 /* we pretend the remote lockspace exists with 0 status */
 162                 log_debug(ls, "remote node %d not ready", nodeid);
 163                 rc->rc_result = 0;
 164         } else
 165                 error = check_config(ls, rc, nodeid);
 166         /* the caller looks at rc_result for the remote recovery status */
 167  out:
 168         return error;
 169 }
 170
 171 static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 172 {
 173         struct dlm_rcom *rc;
 174         struct dlm_mhandle *mh;
 175         int error, nodeid = rc_in->rc_header.h_nodeid;
 176
 177         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
 178                             sizeof(struct rcom_config), &rc, &mh);
 179         if (error)
 180                 return;
 181         rc->rc_id = rc_in->rc_id;
 182         rc->rc_seq_reply = rc_in->rc_seq;
 183         rc->rc_result = dlm_recover_status(ls);
 184         make_config(ls, (struct rcom_config *) rc->rc_buf);
 185
 186         send_rcom(ls, mh, rc);
 187 }
 188
 189 static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 190 {
 191         spin_lock(&ls->ls_rcom_spin);
 192         if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
 193             rc_in->rc_id != ls->ls_rcom_seq) {
 194                 log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
 195                           rc_in->rc_type, rc_in->rc_header.h_nodeid,
 196                           (unsigned long long)rc_in->rc_id,
 197                           (unsigned long long)ls->ls_rcom_seq);
 198                 goto out;
 199         }
 200         memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
 201         set_bit(LSFL_RCOM_READY, &ls->ls_flags);
 202         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 203         wake_up(&ls->ls_wait_general);
 204  out:
 205         spin_unlock(&ls->ls_rcom_spin);
 206 }
 207
 208 int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
 209 {
 210         struct dlm_rcom *rc;
 211         struct dlm_mhandle *mh;
 212         int error = 0;
 213         int max_size = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom);
 214
 215         ls->ls_recover_nodeid = nodeid;
 216
 217         if (nodeid == dlm_our_nodeid()) {
 218                 dlm_copy_master_names(ls, last_name, last_len,
 219                                       ls->ls_recover_buf->rc_buf,
 220                                       max_size, nodeid);
 221                 goto out;
 222         }
 223
 224         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
 225         if (error)
 226                 goto out;
 227         memcpy(rc->rc_buf, last_name, last_len);
 228
 229         allow_sync_reply(ls, &rc->rc_id);
 230         memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
 231
 232         send_rcom(ls, mh, rc);
 233
 234         error = dlm_wait_function(ls, &rcom_response);
 235         disallow_sync_reply(ls);
 236  out:
 237         return error;
 238 }
 239
 240 static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 241 {
 242         struct dlm_rcom *rc;
 243         struct dlm_mhandle *mh;
 244         int error, inlen, outlen, nodeid;
 245
 246         nodeid = rc_in->rc_header.h_nodeid;
 247         inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 248         outlen = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom);
 249
 250         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
 251         if (error)
 252                 return;
 253         rc->rc_id = rc_in->rc_id;
 254         rc->rc_seq_reply = rc_in->rc_seq;
 255
 256         dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
 257                               nodeid);
 258         send_rcom(ls, mh, rc);
 259 }
 260
 261 int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
 262 {
 263         struct dlm_rcom *rc;
 264         struct dlm_mhandle *mh;
 265         struct dlm_ls *ls = r->res_ls;
 266         int error;
 267
 268         error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
 269                             &rc, &mh);
 270         if (error)
 271                 goto out;
 272         memcpy(rc->rc_buf, r->res_name, r->res_length);
 273         rc->rc_id = (unsigned long) r;
 274
 275         send_rcom(ls, mh, rc);
 276  out:
 277         return error;
 278 }
 279
 280 static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 281 {
 282         struct dlm_rcom *rc;
 283         struct dlm_mhandle *mh;
 284         int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
 285         int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 286
 287         error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
 288         if (error)
 289                 return;
 290
 291         error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid);
 292         if (error)
 293                 ret_nodeid = error;
 294         rc->rc_result = ret_nodeid;
 295         rc->rc_id = rc_in->rc_id;
 296         rc->rc_seq_reply = rc_in->rc_seq;
 297
 298         send_rcom(ls, mh, rc);
 299 }
 300
 301 static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 302 {
 303         dlm_recover_master_reply(ls, rc_in);
 304 }
 305
 306 static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
 307                            struct rcom_lock *rl)
 308 {
 309         memset(rl, 0, sizeof(*rl));
 310
 311         rl->rl_ownpid = cpu_to_le32(lkb->lkb_ownpid);
 312         rl->rl_lkid = cpu_to_le32(lkb->lkb_id);
 313         rl->rl_exflags = cpu_to_le32(lkb->lkb_exflags);
 314         rl->rl_flags = cpu_to_le32(lkb->lkb_flags);
 315         rl->rl_lvbseq = cpu_to_le32(lkb->lkb_lvbseq);
 316         rl->rl_rqmode = lkb->lkb_rqmode;
 317         rl->rl_grmode = lkb->lkb_grmode;
 318         rl->rl_status = lkb->lkb_status;
 319         rl->rl_wait_type = cpu_to_le16(lkb->lkb_wait_type);
 320
 321         if (lkb->lkb_bastaddr)
 322                 rl->rl_asts |= AST_BAST;
 323         if (lkb->lkb_astaddr)
 324                 rl->rl_asts |= AST_COMP;
 325
 326         rl->rl_namelen = cpu_to_le16(r->res_length);
 327         memcpy(rl->rl_name, r->res_name, r->res_length);
 328
 329         /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
 330            If so, receive_rcom_lock_args() won't take this copy. */
 331
 332         if (lkb->lkb_lvbptr)
 333                 memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
 334 }
 335
 336 int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
 337 {
 338         struct dlm_ls *ls = r->res_ls;
 339         struct dlm_rcom *rc;
 340         struct dlm_mhandle *mh;
 341         struct rcom_lock *rl;
 342         int error, len = sizeof(struct rcom_lock);
 343
 344         if (lkb->lkb_lvbptr)
 345                 len += ls->ls_lvblen;
 346
 347         error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
 348         if (error)
 349                 goto out;
 350
 351         rl = (struct rcom_lock *) rc->rc_buf;
 352         pack_rcom_lock(r, lkb, rl);
 353         rc->rc_id = (unsigned long) r;
 354
 355         send_rcom(ls, mh, rc);
 356  out:
 357         return error;
 358 }
 359
 360 /* needs at least dlm_rcom + rcom_lock */
 361 static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 362 {
 363         struct dlm_rcom *rc;
 364         struct dlm_mhandle *mh;
 365         int error, nodeid = rc_in->rc_header.h_nodeid;
 366
 367         dlm_recover_master_copy(ls, rc_in);
 368
 369         error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
 370                             sizeof(struct rcom_lock), &rc, &mh);
 371         if (error)
 372                 return;
 373
 374         /* We send back the same rcom_lock struct we received, but
 375            dlm_recover_master_copy() has filled in rl_remid and rl_result */
 376
 377         memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
 378         rc->rc_id = rc_in->rc_id;
 379         rc->rc_seq_reply = rc_in->rc_seq;
 380
 381         send_rcom(ls, mh, rc);
 382 }
 383
 384 /* If the lockspace doesn't exist then still send a status message
 385    back; it's possible that it just doesn't have its global_id yet. */
 386
 387 int dlm_send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
 388 {
 389         struct dlm_rcom *rc;
 390         struct rcom_config *rf;
 391         struct dlm_mhandle *mh;
 392         char *mb;
 393         int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
 394
 395         mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_NOFS, &mb);
 396         if (!mh)
 397                 return -ENOBUFS;
 398         memset(mb, 0, mb_len);
 399
 400         rc = (struct dlm_rcom *) mb;
 401
 402         rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
 403         rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
 404         rc->rc_header.h_nodeid = dlm_our_nodeid();
 405         rc->rc_header.h_length = mb_len;
 406         rc->rc_header.h_cmd = DLM_RCOM;
 407
 408         rc->rc_type = DLM_RCOM_STATUS_REPLY;
 409         rc->rc_id = rc_in->rc_id;
 410         rc->rc_seq_reply = rc_in->rc_seq;
 411         rc->rc_result = -ESRCH;
 412
 413         rf = (struct rcom_config *) rc->rc_buf;
 414         rf->rf_lvblen = cpu_to_le32(~0U);
 415
 416         dlm_rcom_out(rc);
 417         dlm_lowcomms_commit_buffer(mh);
 418
 419         return 0;
 420 }
 421
 422 static int is_old_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
 423 {
 424         uint64_t seq;
 425         int rv = 0;
 426
 427         switch (rc->rc_type) {
 428         case DLM_RCOM_STATUS_REPLY:
 429         case DLM_RCOM_NAMES_REPLY:
 430         case DLM_RCOM_LOOKUP_REPLY:
 431         case DLM_RCOM_LOCK_REPLY:
 432                 spin_lock(&ls->ls_recover_lock);
 433                 seq = ls->ls_recover_seq;
 434                 spin_unlock(&ls->ls_recover_lock);
 435                 if (rc->rc_seq_reply != seq) {
 436                         log_debug(ls, "ignoring old reply %x from %d "
 437                                       "seq_reply %llx expect %llx",
 438                                       rc->rc_type, rc->rc_header.h_nodeid,
 439                                       (unsigned long long)rc->rc_seq_reply,
 440                                       (unsigned long long)seq);
 441                         rv = 1;
 442                 }
 443         }
 444         return rv;
 445 }
 446
 447 /* Called by dlm_recv; corresponds to dlm_receive_message() but special
 448    recovery-only comms are sent through here. */
 449
 450 void dlm_receive_rcom(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
 451 {
 452         int lock_size = sizeof(struct dlm_rcom) + sizeof(struct rcom_lock);
 453
 454         if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
 455                 log_debug(ls, "ignoring recovery message %x from %d",
 456                           rc->rc_type, nodeid);
 457                 goto out;
 458         }
 459
 460         if (is_old_reply(ls, rc))
 461                 goto out;
 462
 463         switch (rc->rc_type) {
 464         case DLM_RCOM_STATUS:
 465                 receive_rcom_status(ls, rc);
 466                 break;
 467
 468         case DLM_RCOM_NAMES:
 469                 receive_rcom_names(ls, rc);
 470                 break;
 471
 472         case DLM_RCOM_LOOKUP:
 473                 receive_rcom_lookup(ls, rc);
 474                 break;
 475
 476         case DLM_RCOM_LOCK:
 477                 if (rc->rc_header.h_length < lock_size)
 478                         goto Eshort;
 479                 receive_rcom_lock(ls, rc);
 480                 break;
 481
 482         case DLM_RCOM_STATUS_REPLY:
 483                 receive_sync_reply(ls, rc);
 484                 break;
 485
 486         case DLM_RCOM_NAMES_REPLY:
 487                 receive_sync_reply(ls, rc);
 488                 break;
 489
 490         case DLM_RCOM_LOOKUP_REPLY:
 491                 receive_rcom_lookup_reply(ls, rc);
 492                 break;
 493
 494         case DLM_RCOM_LOCK_REPLY:
 495                 if (rc->rc_header.h_length < lock_size)
 496                         goto Eshort;
 497                 dlm_recover_process_copy(ls, rc);
 498                 break;
 499
 500         default:
 501                 log_error(ls, "receive_rcom bad type %d", rc->rc_type);
 502         }
 503 out:
 504         return;
 505 Eshort:
 506         log_error(ls, "recovery message %x from %d is too short",
 507                           rc->rc_type, nodeid);
 508 }
 509