git.oblomov.eu Git - 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         *mh_ret = mh;
  60         *rc_ret = rc;
  61         return 0;
  62 }
  63
  64 static void send_rcom(struct dlm_ls *ls, struct dlm_mhandle *mh,
  65                       struct dlm_rcom *rc)
  66 {
  67         dlm_rcom_out(rc);
  68         dlm_lowcomms_commit_buffer(mh);
  69 }
  70
  71 /* When replying to a status request, a node also sends back its
  72    configuration values.  The requesting node then checks that the remote
  73    node is configured the same way as itself. */
  74
  75 static void make_config(struct dlm_ls *ls, struct rcom_config *rf)
  76 {
  77         rf->rf_lvblen = ls->ls_lvblen;
  78         rf->rf_lsflags = ls->ls_exflags;
  79 }
  80
  81 static int check_config(struct dlm_ls *ls, struct rcom_config *rf, int nodeid)
  82 {
  83         if (rf->rf_lvblen != ls->ls_lvblen ||
  84             rf->rf_lsflags != ls->ls_exflags) {
  85                 log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x",
  86                           ls->ls_lvblen, ls->ls_exflags,
  87                           nodeid, rf->rf_lvblen, rf->rf_lsflags);
  88                 return -EINVAL;
  89         }
  90         return 0;
  91 }
  92
  93 static void allow_sync_reply(struct dlm_ls *ls, uint64_t *new_seq)
  94 {
  95         spin_lock(&ls->ls_rcom_spin);
  96         *new_seq = ++ls->ls_rcom_seq;
  97         set_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
  98         spin_unlock(&ls->ls_rcom_spin);
  99 }
 100
 101 static void disallow_sync_reply(struct dlm_ls *ls)
 102 {
 103         spin_lock(&ls->ls_rcom_spin);
 104         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 105         clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
 106         spin_unlock(&ls->ls_rcom_spin);
 107 }
 108
 109 int dlm_rcom_status(struct dlm_ls *ls, int nodeid)
 110 {
 111         struct dlm_rcom *rc;
 112         struct dlm_mhandle *mh;
 113         int error = 0;
 114
 115         ls->ls_recover_nodeid = nodeid;
 116
 117         if (nodeid == dlm_our_nodeid()) {
 118                 rc = (struct dlm_rcom *) ls->ls_recover_buf;
 119                 rc->rc_result = dlm_recover_status(ls);
 120                 goto out;
 121         }
 122
 123         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh);
 124         if (error)
 125                 goto out;
 126
 127         allow_sync_reply(ls, &rc->rc_id);
 128         memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);
 129
 130         send_rcom(ls, mh, rc);
 131
 132         error = dlm_wait_function(ls, &rcom_response);
 133         disallow_sync_reply(ls);
 134         if (error)
 135                 goto out;
 136
 137         rc = (struct dlm_rcom *) ls->ls_recover_buf;
 138
 139         if (rc->rc_result == -ESRCH) {
 140                 /* we pretend the remote lockspace exists with 0 status */
 141                 log_debug(ls, "remote node %d not ready", nodeid);
 142                 rc->rc_result = 0;
 143         } else
 144                 error = check_config(ls, (struct rcom_config *) rc->rc_buf,
 145                                      nodeid);
 146         /* the caller looks at rc_result for the remote recovery status */
 147  out:
 148         return error;
 149 }
 150
 151 static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 152 {
 153         struct dlm_rcom *rc;
 154         struct dlm_mhandle *mh;
 155         int error, nodeid = rc_in->rc_header.h_nodeid;
 156
 157         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
 158                             sizeof(struct rcom_config), &rc, &mh);
 159         if (error)
 160                 return;
 161         rc->rc_id = rc_in->rc_id;
 162         rc->rc_result = dlm_recover_status(ls);
 163         make_config(ls, (struct rcom_config *) rc->rc_buf);
 164
 165         send_rcom(ls, mh, rc);
 166 }
 167
 168 static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 169 {
 170         spin_lock(&ls->ls_rcom_spin);
 171         if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
 172             rc_in->rc_id != ls->ls_rcom_seq) {
 173                 log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
 174                           rc_in->rc_type, rc_in->rc_header.h_nodeid,
 175                           (unsigned long long)rc_in->rc_id,
 176                           (unsigned long long)ls->ls_rcom_seq);
 177                 goto out;
 178         }
 179         memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
 180         set_bit(LSFL_RCOM_READY, &ls->ls_flags);
 181         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 182         wake_up(&ls->ls_wait_general);
 183  out:
 184         spin_unlock(&ls->ls_rcom_spin);
 185 }
 186
 187 static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 188 {
 189         receive_sync_reply(ls, rc_in);
 190 }
 191
 192 int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
 193 {
 194         struct dlm_rcom *rc;
 195         struct dlm_mhandle *mh;
 196         int error = 0, len = sizeof(struct dlm_rcom);
 197
 198         ls->ls_recover_nodeid = nodeid;
 199
 200         if (nodeid == dlm_our_nodeid()) {
 201                 dlm_copy_master_names(ls, last_name, last_len,
 202                                       ls->ls_recover_buf + len,
 203                                       dlm_config.buffer_size - len, nodeid);
 204                 goto out;
 205         }
 206
 207         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
 208         if (error)
 209                 goto out;
 210         memcpy(rc->rc_buf, last_name, last_len);
 211
 212         allow_sync_reply(ls, &rc->rc_id);
 213         memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);
 214
 215         send_rcom(ls, mh, rc);
 216
 217         error = dlm_wait_function(ls, &rcom_response);
 218         disallow_sync_reply(ls);
 219  out:
 220         return error;
 221 }
 222
 223 static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 224 {
 225         struct dlm_rcom *rc;
 226         struct dlm_mhandle *mh;
 227         int error, inlen, outlen;
 228         int nodeid = rc_in->rc_header.h_nodeid;
 229         uint32_t status = dlm_recover_status(ls);
 230
 231         /*
 232          * We can't run dlm_dir_rebuild_send (which uses ls_nodes) while
 233          * dlm_recoverd is running ls_nodes_reconfig (which changes ls_nodes).
 234          * It could only happen in rare cases where we get a late NAMES
 235          * message from a previous instance of recovery.
 236          */
 237
 238         if (!(status & DLM_RS_NODES)) {
 239                 log_debug(ls, "ignoring RCOM_NAMES from %u", nodeid);
 240                 return;
 241         }
 242
 243         nodeid = rc_in->rc_header.h_nodeid;
 244         inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 245         outlen = dlm_config.buffer_size - sizeof(struct dlm_rcom);
 246
 247         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
 248         if (error)
 249                 return;
 250         rc->rc_id = rc_in->rc_id;
 251
 252         dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
 253                               nodeid);
 254         send_rcom(ls, mh, rc);
 255 }
 256
 257 static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 258 {
 259         receive_sync_reply(ls, rc_in);
 260 }
 261
 262 int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
 263 {
 264         struct dlm_rcom *rc;
 265         struct dlm_mhandle *mh;
 266         struct dlm_ls *ls = r->res_ls;
 267         int error;
 268
 269         error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
 270                             &rc, &mh);
 271         if (error)
 272                 goto out;
 273         memcpy(rc->rc_buf, r->res_name, r->res_length);
 274         rc->rc_id = (unsigned long) r;
 275
 276         send_rcom(ls, mh, rc);
 277  out:
 278         return error;
 279 }
 280
 281 static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 282 {
 283         struct dlm_rcom *rc;
 284         struct dlm_mhandle *mh;
 285         int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
 286         int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 287
 288         error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
 289         if (error)
 290                 return;
 291
 292         error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid);
 293         if (error)
 294                 ret_nodeid = error;
 295         rc->rc_result = ret_nodeid;
 296         rc->rc_id = rc_in->rc_id;
 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 = lkb->lkb_ownpid;
 312         rl->rl_lkid = lkb->lkb_id;
 313         rl->rl_exflags = lkb->lkb_exflags;
 314         rl->rl_flags = lkb->lkb_flags;
 315         rl->rl_lvbseq = 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 = 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 = 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 static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 361 {
 362         struct dlm_rcom *rc;
 363         struct dlm_mhandle *mh;
 364         int error, nodeid = rc_in->rc_header.h_nodeid;
 365
 366         dlm_recover_master_copy(ls, rc_in);
 367
 368         error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
 369                             sizeof(struct rcom_lock), &rc, &mh);
 370         if (error)
 371                 return;
 372
 373         /* We send back the same rcom_lock struct we received, but
 374            dlm_recover_master_copy() has filled in rl_remid and rl_result */
 375
 376         memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
 377         rc->rc_id = rc_in->rc_id;
 378
 379         send_rcom(ls, mh, rc);
 380 }
 381
 382 static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 383 {
 384         uint32_t status = dlm_recover_status(ls);
 385
 386         if (!(status & DLM_RS_DIR)) {
 387                 log_debug(ls, "ignoring RCOM_LOCK_REPLY from %u",
 388                           rc_in->rc_header.h_nodeid);
 389                 return;
 390         }
 391
 392         dlm_recover_process_copy(ls, rc_in);
 393 }
 394
 395 static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
 396 {
 397         struct dlm_rcom *rc;
 398         struct rcom_config *rf;
 399         struct dlm_mhandle *mh;
 400         char *mb;
 401         int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
 402
 403         mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb);
 404         if (!mh)
 405                 return -ENOBUFS;
 406         memset(mb, 0, mb_len);
 407
 408         rc = (struct dlm_rcom *) mb;
 409
 410         rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
 411         rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
 412         rc->rc_header.h_nodeid = dlm_our_nodeid();
 413         rc->rc_header.h_length = mb_len;
 414         rc->rc_header.h_cmd = DLM_RCOM;
 415
 416         rc->rc_type = DLM_RCOM_STATUS_REPLY;
 417         rc->rc_id = rc_in->rc_id;
 418         rc->rc_result = -ESRCH;
 419
 420         rf = (struct rcom_config *) rc->rc_buf;
 421         rf->rf_lvblen = -1;
 422
 423         dlm_rcom_out(rc);
 424         dlm_lowcomms_commit_buffer(mh);
 425
 426         return 0;
 427 }
 428
 429 /* Called by dlm_recvd; corresponds to dlm_receive_message() but special
 430    recovery-only comms are sent through here. */
 431
 432 void dlm_receive_rcom(struct dlm_header *hd, int nodeid)
 433 {
 434         struct dlm_rcom *rc = (struct dlm_rcom *) hd;
 435         struct dlm_ls *ls;
 436
 437         dlm_rcom_in(rc);
 438
 439         /* If the lockspace doesn't exist then still send a status message
 440            back; it's possible that it just doesn't have its global_id yet. */
 441
 442         ls = dlm_find_lockspace_global(hd->h_lockspace);
 443         if (!ls) {
 444                 log_print("lockspace %x from %d type %x not found",
 445                           hd->h_lockspace, nodeid, rc->rc_type);
 446                 if (rc->rc_type == DLM_RCOM_STATUS)
 447                         send_ls_not_ready(nodeid, rc);
 448                 return;
 449         }
 450
 451         if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
 452                 log_error(ls, "ignoring recovery message %x from %d",
 453                           rc->rc_type, nodeid);
 454                 goto out;
 455         }
 456
 457         if (nodeid != rc->rc_header.h_nodeid) {
 458                 log_error(ls, "bad rcom nodeid %d from %d",
 459                           rc->rc_header.h_nodeid, nodeid);
 460                 goto out;
 461         }
 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                 receive_rcom_lock(ls, rc);
 478                 break;
 479
 480         case DLM_RCOM_STATUS_REPLY:
 481                 receive_rcom_status_reply(ls, rc);
 482                 break;
 483
 484         case DLM_RCOM_NAMES_REPLY:
 485                 receive_rcom_names_reply(ls, rc);
 486                 break;
 487
 488         case DLM_RCOM_LOOKUP_REPLY:
 489                 receive_rcom_lookup_reply(ls, rc);
 490                 break;
 491
 492         case DLM_RCOM_LOCK_REPLY:
 493                 receive_rcom_lock_reply(ls, rc);
 494                 break;
 495
 496         default:
 497                 DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type););
 498         }
 499  out:
 500         dlm_put_lockspace(ls);
 501 }
 502