Pileus Git - ~andy/linux/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                           rc_in->rc_id, ls->ls_rcom_seq);
 176                 goto out;
 177         }
 178         memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
 179         set_bit(LSFL_RCOM_READY, &ls->ls_flags);
 180         clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
 181         wake_up(&ls->ls_wait_general);
 182  out:
 183         spin_unlock(&ls->ls_rcom_spin);
 184 }
 185
 186 static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 187 {
 188         receive_sync_reply(ls, rc_in);
 189 }
 190
 191 int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
 192 {
 193         struct dlm_rcom *rc;
 194         struct dlm_mhandle *mh;
 195         int error = 0, len = sizeof(struct dlm_rcom);
 196
 197         ls->ls_recover_nodeid = nodeid;
 198
 199         if (nodeid == dlm_our_nodeid()) {
 200                 dlm_copy_master_names(ls, last_name, last_len,
 201                                       ls->ls_recover_buf + len,
 202                                       dlm_config.buffer_size - len, nodeid);
 203                 goto out;
 204         }
 205
 206         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
 207         if (error)
 208                 goto out;
 209         memcpy(rc->rc_buf, last_name, last_len);
 210
 211         allow_sync_reply(ls, &rc->rc_id);
 212         memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);
 213
 214         send_rcom(ls, mh, rc);
 215
 216         error = dlm_wait_function(ls, &rcom_response);
 217         disallow_sync_reply(ls);
 218  out:
 219         return error;
 220 }
 221
 222 static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 223 {
 224         struct dlm_rcom *rc;
 225         struct dlm_mhandle *mh;
 226         int error, inlen, outlen;
 227         int nodeid = rc_in->rc_header.h_nodeid;
 228         uint32_t status = dlm_recover_status(ls);
 229
 230         /*
 231          * We can't run dlm_dir_rebuild_send (which uses ls_nodes) while
 232          * dlm_recoverd is running ls_nodes_reconfig (which changes ls_nodes).
 233          * It could only happen in rare cases where we get a late NAMES
 234          * message from a previous instance of recovery.
 235          */
 236
 237         if (!(status & DLM_RS_NODES)) {
 238                 log_debug(ls, "ignoring RCOM_NAMES from %u", nodeid);
 239                 return;
 240         }
 241
 242         nodeid = rc_in->rc_header.h_nodeid;
 243         inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 244         outlen = dlm_config.buffer_size - sizeof(struct dlm_rcom);
 245
 246         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
 247         if (error)
 248                 return;
 249         rc->rc_id = rc_in->rc_id;
 250
 251         dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
 252                               nodeid);
 253         send_rcom(ls, mh, rc);
 254 }
 255
 256 static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 257 {
 258         receive_sync_reply(ls, rc_in);
 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
 297         send_rcom(ls, mh, rc);
 298 }
 299
 300 static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 301 {
 302         dlm_recover_master_reply(ls, rc_in);
 303 }
 304
 305 static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
 306                            struct rcom_lock *rl)
 307 {
 308         memset(rl, 0, sizeof(*rl));
 309
 310         rl->rl_ownpid = lkb->lkb_ownpid;
 311         rl->rl_lkid = lkb->lkb_id;
 312         rl->rl_exflags = lkb->lkb_exflags;
 313         rl->rl_flags = lkb->lkb_flags;
 314         rl->rl_lvbseq = lkb->lkb_lvbseq;
 315         rl->rl_rqmode = lkb->lkb_rqmode;
 316         rl->rl_grmode = lkb->lkb_grmode;
 317         rl->rl_status = lkb->lkb_status;
 318         rl->rl_wait_type = lkb->lkb_wait_type;
 319
 320         if (lkb->lkb_bastaddr)
 321                 rl->rl_asts |= AST_BAST;
 322         if (lkb->lkb_astaddr)
 323                 rl->rl_asts |= AST_COMP;
 324
 325         rl->rl_namelen = r->res_length;
 326         memcpy(rl->rl_name, r->res_name, r->res_length);
 327
 328         /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
 329            If so, receive_rcom_lock_args() won't take this copy. */
 330
 331         if (lkb->lkb_lvbptr)
 332                 memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
 333 }
 334
 335 int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
 336 {
 337         struct dlm_ls *ls = r->res_ls;
 338         struct dlm_rcom *rc;
 339         struct dlm_mhandle *mh;
 340         struct rcom_lock *rl;
 341         int error, len = sizeof(struct rcom_lock);
 342
 343         if (lkb->lkb_lvbptr)
 344                 len += ls->ls_lvblen;
 345
 346         error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
 347         if (error)
 348                 goto out;
 349
 350         rl = (struct rcom_lock *) rc->rc_buf;
 351         pack_rcom_lock(r, lkb, rl);
 352         rc->rc_id = (unsigned long) r;
 353
 354         send_rcom(ls, mh, rc);
 355  out:
 356         return error;
 357 }
 358
 359 static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 360 {
 361         struct dlm_rcom *rc;
 362         struct dlm_mhandle *mh;
 363         int error, nodeid = rc_in->rc_header.h_nodeid;
 364
 365         dlm_recover_master_copy(ls, rc_in);
 366
 367         error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
 368                             sizeof(struct rcom_lock), &rc, &mh);
 369         if (error)
 370                 return;
 371
 372         /* We send back the same rcom_lock struct we received, but
 373            dlm_recover_master_copy() has filled in rl_remid and rl_result */
 374
 375         memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
 376         rc->rc_id = rc_in->rc_id;
 377
 378         send_rcom(ls, mh, rc);
 379 }
 380
 381 static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 382 {
 383         uint32_t status = dlm_recover_status(ls);
 384
 385         if (!(status & DLM_RS_DIR)) {
 386                 log_debug(ls, "ignoring RCOM_LOCK_REPLY from %u",
 387                           rc_in->rc_header.h_nodeid);
 388                 return;
 389         }
 390
 391         dlm_recover_process_copy(ls, rc_in);
 392 }
 393
 394 static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
 395 {
 396         struct dlm_rcom *rc;
 397         struct rcom_config *rf;
 398         struct dlm_mhandle *mh;
 399         char *mb;
 400         int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
 401
 402         mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb);
 403         if (!mh)
 404                 return -ENOBUFS;
 405         memset(mb, 0, mb_len);
 406
 407         rc = (struct dlm_rcom *) mb;
 408
 409         rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
 410         rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
 411         rc->rc_header.h_nodeid = dlm_our_nodeid();
 412         rc->rc_header.h_length = mb_len;
 413         rc->rc_header.h_cmd = DLM_RCOM;
 414
 415         rc->rc_type = DLM_RCOM_STATUS_REPLY;
 416         rc->rc_id = rc_in->rc_id;
 417         rc->rc_result = -ESRCH;
 418
 419         rf = (struct rcom_config *) rc->rc_buf;
 420         rf->rf_lvblen = -1;
 421
 422         dlm_rcom_out(rc);
 423         dlm_lowcomms_commit_buffer(mh);
 424
 425         return 0;
 426 }
 427
 428 /* Called by dlm_recvd; corresponds to dlm_receive_message() but special
 429    recovery-only comms are sent through here. */
 430
 431 void dlm_receive_rcom(struct dlm_header *hd, int nodeid)
 432 {
 433         struct dlm_rcom *rc = (struct dlm_rcom *) hd;
 434         struct dlm_ls *ls;
 435
 436         dlm_rcom_in(rc);
 437
 438         /* If the lockspace doesn't exist then still send a status message
 439            back; it's possible that it just doesn't have its global_id yet. */
 440
 441         ls = dlm_find_lockspace_global(hd->h_lockspace);
 442         if (!ls) {
 443                 log_print("lockspace %x from %d type %x not found",
 444                           hd->h_lockspace, nodeid, rc->rc_type);
 445                 if (rc->rc_type == DLM_RCOM_STATUS)
 446                         send_ls_not_ready(nodeid, rc);
 447                 return;
 448         }
 449
 450         if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
 451                 log_error(ls, "ignoring recovery message %x from %d",
 452                           rc->rc_type, nodeid);
 453                 goto out;
 454         }
 455
 456         if (nodeid != rc->rc_header.h_nodeid) {
 457                 log_error(ls, "bad rcom nodeid %d from %d",
 458                           rc->rc_header.h_nodeid, nodeid);
 459                 goto out;
 460         }
 461
 462         switch (rc->rc_type) {
 463         case DLM_RCOM_STATUS:
 464                 receive_rcom_status(ls, rc);
 465                 break;
 466
 467         case DLM_RCOM_NAMES:
 468                 receive_rcom_names(ls, rc);
 469                 break;
 470
 471         case DLM_RCOM_LOOKUP:
 472                 receive_rcom_lookup(ls, rc);
 473                 break;
 474
 475         case DLM_RCOM_LOCK:
 476                 receive_rcom_lock(ls, rc);
 477                 break;
 478
 479         case DLM_RCOM_STATUS_REPLY:
 480                 receive_rcom_status_reply(ls, rc);
 481                 break;
 482
 483         case DLM_RCOM_NAMES_REPLY:
 484                 receive_rcom_names_reply(ls, rc);
 485                 break;
 486
 487         case DLM_RCOM_LOOKUP_REPLY:
 488                 receive_rcom_lookup_reply(ls, rc);
 489                 break;
 490
 491         case DLM_RCOM_LOCK_REPLY:
 492                 receive_rcom_lock_reply(ls, rc);
 493                 break;
 494
 495         default:
 496                 DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type););
 497         }
 498  out:
 499         dlm_put_lockspace(ls);
 500 }
 501