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 int dlm_rcom_status(struct dlm_ls *ls, int nodeid)
  94 {
  95         struct dlm_rcom *rc;
  96         struct dlm_mhandle *mh;
  97         int error = 0;
  98
  99         memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);
 100         ls->ls_recover_nodeid = nodeid;
 101
 102         if (nodeid == dlm_our_nodeid()) {
 103                 rc = (struct dlm_rcom *) ls->ls_recover_buf;
 104                 rc->rc_result = dlm_recover_status(ls);
 105                 goto out;
 106         }
 107
 108         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh);
 109         if (error)
 110                 goto out;
 111         rc->rc_id = ++ls->ls_rcom_seq;
 112
 113         send_rcom(ls, mh, rc);
 114
 115         error = dlm_wait_function(ls, &rcom_response);
 116         clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
 117         if (error)
 118                 goto out;
 119
 120         rc = (struct dlm_rcom *) ls->ls_recover_buf;
 121
 122         if (rc->rc_result == -ESRCH) {
 123                 /* we pretend the remote lockspace exists with 0 status */
 124                 log_debug(ls, "remote node %d not ready", nodeid);
 125                 rc->rc_result = 0;
 126         } else
 127                 error = check_config(ls, (struct rcom_config *) rc->rc_buf,
 128                                      nodeid);
 129         /* the caller looks at rc_result for the remote recovery status */
 130  out:
 131         return error;
 132 }
 133
 134 static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 135 {
 136         struct dlm_rcom *rc;
 137         struct dlm_mhandle *mh;
 138         int error, nodeid = rc_in->rc_header.h_nodeid;
 139
 140         error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
 141                             sizeof(struct rcom_config), &rc, &mh);
 142         if (error)
 143                 return;
 144         rc->rc_id = rc_in->rc_id;
 145         rc->rc_result = dlm_recover_status(ls);
 146         make_config(ls, (struct rcom_config *) rc->rc_buf);
 147
 148         send_rcom(ls, mh, rc);
 149 }
 150
 151 static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 152 {
 153         if (rc_in->rc_id != ls->ls_rcom_seq) {
 154                 log_debug(ls, "reject old reply %d got %llx wanted %llx",
 155                           rc_in->rc_type, rc_in->rc_id, ls->ls_rcom_seq);
 156                 return;
 157         }
 158         memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
 159         set_bit(LSFL_RCOM_READY, &ls->ls_flags);
 160         wake_up(&ls->ls_wait_general);
 161 }
 162
 163 static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 164 {
 165         receive_sync_reply(ls, rc_in);
 166 }
 167
 168 int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
 169 {
 170         struct dlm_rcom *rc;
 171         struct dlm_mhandle *mh;
 172         int error = 0, len = sizeof(struct dlm_rcom);
 173
 174         memset(ls->ls_recover_buf, 0, dlm_config.buffer_size);
 175         ls->ls_recover_nodeid = nodeid;
 176
 177         if (nodeid == dlm_our_nodeid()) {
 178                 dlm_copy_master_names(ls, last_name, last_len,
 179                                       ls->ls_recover_buf + len,
 180                                       dlm_config.buffer_size - len, nodeid);
 181                 goto out;
 182         }
 183
 184         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
 185         if (error)
 186                 goto out;
 187         memcpy(rc->rc_buf, last_name, last_len);
 188         rc->rc_id = ++ls->ls_rcom_seq;
 189
 190         send_rcom(ls, mh, rc);
 191
 192         error = dlm_wait_function(ls, &rcom_response);
 193         clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
 194  out:
 195         return error;
 196 }
 197
 198 static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 199 {
 200         struct dlm_rcom *rc;
 201         struct dlm_mhandle *mh;
 202         int error, inlen, outlen;
 203         int nodeid = rc_in->rc_header.h_nodeid;
 204         uint32_t status = dlm_recover_status(ls);
 205
 206         /*
 207          * We can't run dlm_dir_rebuild_send (which uses ls_nodes) while
 208          * dlm_recoverd is running ls_nodes_reconfig (which changes ls_nodes).
 209          * It could only happen in rare cases where we get a late NAMES
 210          * message from a previous instance of recovery.
 211          */
 212
 213         if (!(status & DLM_RS_NODES)) {
 214                 log_debug(ls, "ignoring RCOM_NAMES from %u", nodeid);
 215                 return;
 216         }
 217
 218         nodeid = rc_in->rc_header.h_nodeid;
 219         inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 220         outlen = dlm_config.buffer_size - sizeof(struct dlm_rcom);
 221
 222         error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
 223         if (error)
 224                 return;
 225         rc->rc_id = rc_in->rc_id;
 226
 227         dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
 228                               nodeid);
 229         send_rcom(ls, mh, rc);
 230 }
 231
 232 static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 233 {
 234         receive_sync_reply(ls, rc_in);
 235 }
 236
 237 int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
 238 {
 239         struct dlm_rcom *rc;
 240         struct dlm_mhandle *mh;
 241         struct dlm_ls *ls = r->res_ls;
 242         int error;
 243
 244         error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
 245                             &rc, &mh);
 246         if (error)
 247                 goto out;
 248         memcpy(rc->rc_buf, r->res_name, r->res_length);
 249         rc->rc_id = (unsigned long) r;
 250
 251         send_rcom(ls, mh, rc);
 252  out:
 253         return error;
 254 }
 255
 256 static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 257 {
 258         struct dlm_rcom *rc;
 259         struct dlm_mhandle *mh;
 260         int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
 261         int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
 262
 263         error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
 264         if (error)
 265                 return;
 266
 267         error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid);
 268         if (error)
 269                 ret_nodeid = error;
 270         rc->rc_result = ret_nodeid;
 271         rc->rc_id = rc_in->rc_id;
 272
 273         send_rcom(ls, mh, rc);
 274 }
 275
 276 static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 277 {
 278         dlm_recover_master_reply(ls, rc_in);
 279 }
 280
 281 static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
 282                            struct rcom_lock *rl)
 283 {
 284         memset(rl, 0, sizeof(*rl));
 285
 286         rl->rl_ownpid = lkb->lkb_ownpid;
 287         rl->rl_lkid = lkb->lkb_id;
 288         rl->rl_exflags = lkb->lkb_exflags;
 289         rl->rl_flags = lkb->lkb_flags;
 290         rl->rl_lvbseq = lkb->lkb_lvbseq;
 291         rl->rl_rqmode = lkb->lkb_rqmode;
 292         rl->rl_grmode = lkb->lkb_grmode;
 293         rl->rl_status = lkb->lkb_status;
 294         rl->rl_wait_type = lkb->lkb_wait_type;
 295
 296         if (lkb->lkb_bastaddr)
 297                 rl->rl_asts |= AST_BAST;
 298         if (lkb->lkb_astaddr)
 299                 rl->rl_asts |= AST_COMP;
 300
 301         rl->rl_namelen = r->res_length;
 302         memcpy(rl->rl_name, r->res_name, r->res_length);
 303
 304         /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
 305            If so, receive_rcom_lock_args() won't take this copy. */
 306
 307         if (lkb->lkb_lvbptr)
 308                 memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
 309 }
 310
 311 int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
 312 {
 313         struct dlm_ls *ls = r->res_ls;
 314         struct dlm_rcom *rc;
 315         struct dlm_mhandle *mh;
 316         struct rcom_lock *rl;
 317         int error, len = sizeof(struct rcom_lock);
 318
 319         if (lkb->lkb_lvbptr)
 320                 len += ls->ls_lvblen;
 321
 322         error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
 323         if (error)
 324                 goto out;
 325
 326         rl = (struct rcom_lock *) rc->rc_buf;
 327         pack_rcom_lock(r, lkb, rl);
 328         rc->rc_id = (unsigned long) r;
 329
 330         send_rcom(ls, mh, rc);
 331  out:
 332         return error;
 333 }
 334
 335 static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 336 {
 337         struct dlm_rcom *rc;
 338         struct dlm_mhandle *mh;
 339         int error, nodeid = rc_in->rc_header.h_nodeid;
 340
 341         dlm_recover_master_copy(ls, rc_in);
 342
 343         error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
 344                             sizeof(struct rcom_lock), &rc, &mh);
 345         if (error)
 346                 return;
 347
 348         /* We send back the same rcom_lock struct we received, but
 349            dlm_recover_master_copy() has filled in rl_remid and rl_result */
 350
 351         memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
 352         rc->rc_id = rc_in->rc_id;
 353
 354         send_rcom(ls, mh, rc);
 355 }
 356
 357 static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
 358 {
 359         uint32_t status = dlm_recover_status(ls);
 360
 361         if (!(status & DLM_RS_DIR)) {
 362                 log_debug(ls, "ignoring RCOM_LOCK_REPLY from %u",
 363                           rc_in->rc_header.h_nodeid);
 364                 return;
 365         }
 366
 367         dlm_recover_process_copy(ls, rc_in);
 368 }
 369
 370 static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
 371 {
 372         struct dlm_rcom *rc;
 373         struct dlm_mhandle *mh;
 374         char *mb;
 375         int mb_len = sizeof(struct dlm_rcom);
 376
 377         mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb);
 378         if (!mh)
 379                 return -ENOBUFS;
 380         memset(mb, 0, mb_len);
 381
 382         rc = (struct dlm_rcom *) mb;
 383
 384         rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
 385         rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
 386         rc->rc_header.h_nodeid = dlm_our_nodeid();
 387         rc->rc_header.h_length = mb_len;
 388         rc->rc_header.h_cmd = DLM_RCOM;
 389
 390         rc->rc_type = DLM_RCOM_STATUS_REPLY;
 391         rc->rc_id = rc_in->rc_id;
 392         rc->rc_result = -ESRCH;
 393
 394         dlm_rcom_out(rc);
 395         dlm_lowcomms_commit_buffer(mh);
 396
 397         return 0;
 398 }
 399
 400 /* Called by dlm_recvd; corresponds to dlm_receive_message() but special
 401    recovery-only comms are sent through here. */
 402
 403 void dlm_receive_rcom(struct dlm_header *hd, int nodeid)
 404 {
 405         struct dlm_rcom *rc = (struct dlm_rcom *) hd;
 406         struct dlm_ls *ls;
 407
 408         dlm_rcom_in(rc);
 409
 410         /* If the lockspace doesn't exist then still send a status message
 411            back; it's possible that it just doesn't have its global_id yet. */
 412
 413         ls = dlm_find_lockspace_global(hd->h_lockspace);
 414         if (!ls) {
 415                 log_print("lockspace %x from %d not found",
 416                           hd->h_lockspace, nodeid);
 417                 send_ls_not_ready(nodeid, rc);
 418                 return;
 419         }
 420
 421         if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
 422                 log_error(ls, "ignoring recovery message %x from %d",
 423                           rc->rc_type, nodeid);
 424                 goto out;
 425         }
 426
 427         if (nodeid != rc->rc_header.h_nodeid) {
 428                 log_error(ls, "bad rcom nodeid %d from %d",
 429                           rc->rc_header.h_nodeid, nodeid);
 430                 goto out;
 431         }
 432
 433         switch (rc->rc_type) {
 434         case DLM_RCOM_STATUS:
 435                 receive_rcom_status(ls, rc);
 436                 break;
 437
 438         case DLM_RCOM_NAMES:
 439                 receive_rcom_names(ls, rc);
 440                 break;
 441
 442         case DLM_RCOM_LOOKUP:
 443                 receive_rcom_lookup(ls, rc);
 444                 break;
 445
 446         case DLM_RCOM_LOCK:
 447                 receive_rcom_lock(ls, rc);
 448                 break;
 449
 450         case DLM_RCOM_STATUS_REPLY:
 451                 receive_rcom_status_reply(ls, rc);
 452                 break;
 453
 454         case DLM_RCOM_NAMES_REPLY:
 455                 receive_rcom_names_reply(ls, rc);
 456                 break;
 457
 458         case DLM_RCOM_LOOKUP_REPLY:
 459                 receive_rcom_lookup_reply(ls, rc);
 460                 break;
 461
 462         case DLM_RCOM_LOCK_REPLY:
 463                 receive_rcom_lock_reply(ls, rc);
 464                 break;
 465
 466         default:
 467                 DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type););
 468         }
 469  out:
 470         dlm_put_lockspace(ls);
 471 }
 472