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