lustre/fld/fld_request.c

   1 /* -*- MODE: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  lustre/fld/fld_request.c
   5  *  FLD (Fids Location Database)
   6  *
   7  *  Copyright (C) 2006 Cluster File Systems, Inc.
   8  *   Author: Yury Umanets <umka@clusterfs.com>
   9  *
  10  *   This file is part of the Lustre file system, http://www.lustre.org
  11  *   Lustre is a trademark of Cluster File Systems, Inc.
  12  *
  13  *   You may have signed or agreed to another license before downloading
  14  *   this software.  If so, you are bound by the terms and conditions
  15  *   of that agreement, and the following does not apply to you.  See the
  16  *   LICENSE file included with this distribution for more information.
  17  *
  18  *   If you did not agree to a different license, then this copy of Lustre
  19  *   is open source software; you can redistribute it and/or modify it
  20  *   under the terms of version 2 of the GNU General Public License as
  21  *   published by the Free Software Foundation.
  22  *
  23  *   In either case, Lustre is distributed in the hope that it will be
  24  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  25  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  *   license text for more details.
  27  */
  28 #ifndef EXPORT_SYMTAB
  29 # define EXPORT_SYMTAB
  30 #endif
  31 #define DEBUG_SUBSYSTEM S_FLD
  32
  33 #ifdef __KERNEL__
  34 # include <libcfs/libcfs.h>
  35 # include <linux/module.h>
  36 # include <linux/jbd.h>
  37 # include <asm/div64.h>
  38 #else /* __KERNEL__ */
  39 # include <liblustre.h>
  40 # include <libcfs/list.h>
  41 #endif
  42
  43 #include <obd.h>
  44 #include <obd_class.h>
  45 #include <lustre_ver.h>
  46 #include <obd_support.h>
  47 #include <lprocfs_status.h>
  48
  49 #include <dt_object.h>
  50 #include <md_object.h>
  51 #include <lustre_req_layout.h>
  52 #include <lustre_fld.h>
  53 #include <lustre_mdc.h>
  54 #include "fld_internal.h"
  55
  56 static int fld_rrb_hash(struct lu_client_fld *fld,
  57                         seqno_t seq)
  58 {
  59         LASSERT(fld->lcf_count > 0);
  60         return do_div(seq, fld->lcf_count);
  61 }
  62
  63 static struct lu_fld_target *
  64 fld_rrb_scan(struct lu_client_fld *fld, seqno_t seq)
  65 {
  66         struct lu_fld_target *target;
  67         int hash;
  68         ENTRY;
  69
  70         hash = fld_rrb_hash(fld, seq);
  71
  72         list_for_each_entry(target, &fld->lcf_targets, ft_chain) {
  73                 if (target->ft_idx == hash)
  74                         RETURN(target);
  75         }
  76
  77         CERROR("%s: Can't find target by hash %d (seq "LPX64"). "
  78                "Targets (%d):\n", fld->lcf_name, hash, seq,
  79                fld->lcf_count);
  80
  81         list_for_each_entry(target, &fld->lcf_targets, ft_chain) {
  82                 const char *srv_name = target->ft_srv != NULL  ?
  83                         target->ft_srv->lsf_name : "<null>";
  84                 const char *exp_name = target->ft_exp != NULL ?
  85                         (char *)target->ft_exp->exp_obd->obd_uuid.uuid :
  86                         "<null>";
  87
  88                 CERROR("  exp: 0x%p (%s), srv: 0x%p (%s), idx: "LPU64"\n",
  89                        target->ft_exp, exp_name, target->ft_srv,
  90                        srv_name, target->ft_idx);
  91         }
  92
  93         /*
  94          * If target is not found, there is logical error anyway, so here is
  95          * LBUG() to catch this situation.
  96          */
  97         LBUG();
  98         RETURN(NULL);
  99 }
 100
 101 static int fld_dht_hash(struct lu_client_fld *fld,
 102                         seqno_t seq)
 103 {
 104         /* XXX: here should be DHT hash */
 105         return fld_rrb_hash(fld, seq);
 106 }
 107
 108 static struct lu_fld_target *
 109 fld_dht_scan(struct lu_client_fld *fld, seqno_t seq)
 110 {
 111         /* XXX: here should be DHT scan code */
 112         return fld_rrb_scan(fld, seq);
 113 }
 114
 115 struct lu_fld_hash fld_hash[3] = {
 116         {
 117                 .fh_name = "DHT",
 118                 .fh_hash_func = fld_dht_hash,
 119                 .fh_scan_func = fld_dht_scan
 120         },
 121         {
 122                 .fh_name = "RRB",
 123                 .fh_hash_func = fld_rrb_hash,
 124                 .fh_scan_func = fld_rrb_scan
 125         },
 126         {
 127                 0,
 128         }
 129 };
 130
 131 static struct lu_fld_target *
 132 fld_client_get_target(struct lu_client_fld *fld,
 133                       seqno_t seq)
 134 {
 135         struct lu_fld_target *target;
 136         ENTRY;
 137
 138         LASSERT(fld->lcf_hash != NULL);
 139
 140         spin_lock(&fld->lcf_lock);
 141         target = fld->lcf_hash->fh_scan_func(fld, seq);
 142         spin_unlock(&fld->lcf_lock);
 143
 144         if (target != NULL) {
 145                 CDEBUG(D_INFO, "%s: Found target (idx "LPU64
 146                        ") by seq "LPX64"\n", fld->lcf_name,
 147                        target->ft_idx, seq);
 148         }
 149
 150         RETURN(target);
 151 }
 152
 153 /*
 154  * Add export to FLD. This is usually done by CMM and LMV as they are main users
 155  * of FLD module.
 156  */
 157 int fld_client_add_target(struct lu_client_fld *fld,
 158                           struct lu_fld_target *tar)
 159 {
 160         const char *name = fld_target_name(tar);
 161         struct lu_fld_target *target, *tmp;
 162         ENTRY;
 163
 164         LASSERT(tar != NULL);
 165         LASSERT(name != NULL);
 166         LASSERT(tar->ft_srv != NULL || tar->ft_exp != NULL);
 167
 168         if (fld->lcf_flags != LUSTRE_FLD_INIT) {
 169                 CERROR("%s: Attempt to add target %s (idx "LPU64") "
 170                        "on fly - skip it\n", fld->lcf_name, name,
 171                        tar->ft_idx);
 172                 RETURN(0);
 173         } else {
 174                 CDEBUG(D_INFO, "%s: Adding target %s (idx "
 175                        LPU64")\n", fld->lcf_name, name, tar->ft_idx);
 176         }
 177
 178         OBD_ALLOC_PTR(target);
 179         if (target == NULL)
 180                 RETURN(-ENOMEM);
 181
 182         spin_lock(&fld->lcf_lock);
 183         list_for_each_entry(tmp, &fld->lcf_targets, ft_chain) {
 184                 if (tmp->ft_idx == tar->ft_idx) {
 185                         spin_unlock(&fld->lcf_lock);
 186                         OBD_FREE_PTR(target);
 187                         CERROR("Target %s exists in FLD and known as %s:#"LPU64"\n",
 188                                name, fld_target_name(tmp), tmp->ft_idx);
 189                         RETURN(-EEXIST);
 190                 }
 191         }
 192
 193         target->ft_exp = tar->ft_exp;
 194         if (target->ft_exp != NULL)
 195                 class_export_get(target->ft_exp);
 196         target->ft_srv = tar->ft_srv;
 197         target->ft_idx = tar->ft_idx;
 198
 199         list_add_tail(&target->ft_chain,
 200                       &fld->lcf_targets);
 201
 202         fld->lcf_count++;
 203         spin_unlock(&fld->lcf_lock);
 204
 205         RETURN(0);
 206 }
 207 EXPORT_SYMBOL(fld_client_add_target);
 208
 209 /* Remove export from FLD */
 210 int fld_client_del_target(struct lu_client_fld *fld,
 211                           __u64 idx)
 212 {
 213         struct lu_fld_target *target, *tmp;
 214         ENTRY;
 215
 216         spin_lock(&fld->lcf_lock);
 217         list_for_each_entry_safe(target, tmp,
 218                                  &fld->lcf_targets, ft_chain) {
 219                 if (target->ft_idx == idx) {
 220                         fld->lcf_count--;
 221                         list_del(&target->ft_chain);
 222                         spin_unlock(&fld->lcf_lock);
 223
 224                         if (target->ft_exp != NULL)
 225                                 class_export_put(target->ft_exp);
 226
 227                         OBD_FREE_PTR(target);
 228                         RETURN(0);
 229                 }
 230         }
 231         spin_unlock(&fld->lcf_lock);
 232         RETURN(-ENOENT);
 233 }
 234 EXPORT_SYMBOL(fld_client_del_target);
 235
 236 static void fld_client_proc_fini(struct lu_client_fld *fld);
 237
 238 #ifdef LPROCFS
 239 static int fld_client_proc_init(struct lu_client_fld *fld)
 240 {
 241         int rc;
 242         ENTRY;
 243
 244         fld->lcf_proc_dir = lprocfs_register(fld->lcf_name,
 245                                              fld_type_proc_dir,
 246                                              NULL, NULL);
 247
 248         if (IS_ERR(fld->lcf_proc_dir)) {
 249                 CERROR("%s: LProcFS failed in fld-init\n",
 250                        fld->lcf_name);
 251                 rc = PTR_ERR(fld->lcf_proc_dir);
 252                 RETURN(rc);
 253         }
 254
 255         rc = lprocfs_add_vars(fld->lcf_proc_dir,
 256                               fld_client_proc_list, fld);
 257         if (rc) {
 258                 CERROR("%s: Can't init FLD proc, rc %d\n",
 259                        fld->lcf_name, rc);
 260                 GOTO(out_cleanup, rc);
 261         }
 262
 263         RETURN(0);
 264
 265 out_cleanup:
 266         fld_client_proc_fini(fld);
 267         return rc;
 268 }
 269
 270 static void fld_client_proc_fini(struct lu_client_fld *fld)
 271 {
 272         ENTRY;
 273         if (fld->lcf_proc_dir) {
 274                 if (!IS_ERR(fld->lcf_proc_dir))
 275                         lprocfs_remove(fld->lcf_proc_dir);
 276                 fld->lcf_proc_dir = NULL;
 277         }
 278         EXIT;
 279 }
 280 #else
 281 static int fld_client_proc_init(struct lu_client_fld *fld)
 282 {
 283         return 0;
 284 }
 285
 286 static void fld_client_proc_fini(struct lu_client_fld *fld)
 287 {
 288         return;
 289 }
 290 #endif
 291
 292 static inline int hash_is_sane(int hash)
 293 {
 294         return (hash >= 0 && hash < ARRAY_SIZE(fld_hash));
 295 }
 296
 297 int fld_client_init(struct lu_client_fld *fld,
 298                     const char *prefix, int hash)
 299 {
 300 #ifdef __KERNEL__
 301         int cache_size, cache_threshold;
 302 #endif
 303         int rc;
 304         ENTRY;
 305
 306         LASSERT(fld != NULL);
 307
 308         snprintf(fld->lcf_name, sizeof(fld->lcf_name),
 309                  "cli-%s", prefix);
 310
 311         if (!hash_is_sane(hash)) {
 312                 CERROR("%s: Wrong hash function %#x\n",
 313                        fld->lcf_name, hash);
 314                 RETURN(-EINVAL);
 315         }
 316
 317         fld->lcf_count = 0;
 318         spin_lock_init(&fld->lcf_lock);
 319         fld->lcf_hash = &fld_hash[hash];
 320         fld->lcf_flags = LUSTRE_FLD_INIT;
 321         INIT_LIST_HEAD(&fld->lcf_targets);
 322
 323 #ifdef __KERNEL__
 324         cache_size = FLD_CLIENT_CACHE_SIZE /
 325                 sizeof(struct fld_cache_entry);
 326
 327         cache_threshold = cache_size *
 328                 FLD_CLIENT_CACHE_THRESHOLD / 100;
 329
 330         fld->lcf_cache = fld_cache_init(fld->lcf_name,
 331                                         FLD_CLIENT_HTABLE_SIZE,
 332                                         cache_size, cache_threshold);
 333         if (IS_ERR(fld->lcf_cache)) {
 334                 rc = PTR_ERR(fld->lcf_cache);
 335                 fld->lcf_cache = NULL;
 336                 GOTO(out, rc);
 337         }
 338 #endif
 339
 340         rc = fld_client_proc_init(fld);
 341         if (rc)
 342                 GOTO(out, rc);
 343         EXIT;
 344 out:
 345         if (rc)
 346                 fld_client_fini(fld);
 347         else
 348                 CDEBUG(D_INFO, "%s: Using \"%s\" hash\n",
 349                        fld->lcf_name, fld->lcf_hash->fh_name);
 350         return rc;
 351 }
 352 EXPORT_SYMBOL(fld_client_init);
 353
 354 void fld_client_fini(struct lu_client_fld *fld)
 355 {
 356         struct lu_fld_target *target, *tmp;
 357         ENTRY;
 358
 359         fld_client_proc_fini(fld);
 360
 361         spin_lock(&fld->lcf_lock);
 362         list_for_each_entry_safe(target, tmp,
 363                                  &fld->lcf_targets, ft_chain) {
 364                 fld->lcf_count--;
 365                 list_del(&target->ft_chain);
 366                 if (target->ft_exp != NULL)
 367                         class_export_put(target->ft_exp);
 368                 OBD_FREE_PTR(target);
 369         }
 370         spin_unlock(&fld->lcf_lock);
 371
 372 #ifdef __KERNEL__
 373         if (fld->lcf_cache != NULL) {
 374                 if (!IS_ERR(fld->lcf_cache))
 375                         fld_cache_fini(fld->lcf_cache);
 376                 fld->lcf_cache = NULL;
 377         }
 378 #endif
 379
 380         EXIT;
 381 }
 382 EXPORT_SYMBOL(fld_client_fini);
 383
 384 static int fld_client_rpc(struct obd_export *exp,
 385                           struct md_fld *mf, __u32 fld_op)
 386 {
 387         int size[3] = { sizeof(struct ptlrpc_body),
 388                         sizeof(__u32),
 389                         sizeof(struct md_fld) };
 390         struct ptlrpc_request *req;
 391         struct req_capsule pill;
 392         struct md_fld *pmf;
 393         __u32 *op;
 394         int rc;
 395         ENTRY;
 396
 397         LASSERT(exp != NULL);
 398
 399         req = ptlrpc_prep_req(class_exp2cliimp(exp),
 400                               LUSTRE_MDS_VERSION,
 401                               FLD_QUERY, 3, size,
 402                               NULL);
 403         if (req == NULL)
 404                 RETURN(-ENOMEM);
 405
 406         req_capsule_init(&pill, req, RCL_CLIENT, NULL);
 407         req_capsule_set(&pill, &RQF_FLD_QUERY);
 408
 409         op = req_capsule_client_get(&pill, &RMF_FLD_OPC);
 410         *op = fld_op;
 411
 412         pmf = req_capsule_client_get(&pill, &RMF_FLD_MDFLD);
 413         *pmf = *mf;
 414
 415         size[1] = sizeof(struct md_fld);
 416         ptlrpc_req_set_repsize(req, 2, size);
 417         req->rq_request_portal = FLD_REQUEST_PORTAL;
 418
 419         if (fld_op != FLD_LOOKUP)
 420                 mdc_get_rpc_lock(exp->exp_obd->u.cli.cl_rpc_lock, NULL);
 421         rc = ptlrpc_queue_wait(req);
 422         if (fld_op != FLD_LOOKUP)
 423                 mdc_put_rpc_lock(exp->exp_obd->u.cli.cl_rpc_lock, NULL);
 424         if (rc)
 425                 GOTO(out_req, rc);
 426
 427         pmf = req_capsule_server_get(&pill, &RMF_FLD_MDFLD);
 428         if (pmf == NULL)
 429                 GOTO(out_req, rc = -EFAULT);
 430         *mf = *pmf;
 431         EXIT;
 432 out_req:
 433         req_capsule_fini(&pill);
 434         ptlrpc_req_finished(req);
 435         return rc;
 436 }
 437
 438 int fld_client_create(struct lu_client_fld *fld,
 439                       seqno_t seq, mdsno_t mds,
 440                       const struct lu_env *env)
 441 {
 442         struct md_fld md_fld = { .mf_seq = seq, .mf_mds = mds };
 443         struct lu_fld_target *target;
 444         int rc;
 445         ENTRY;
 446
 447         fld->lcf_flags |= LUSTRE_FLD_RUN;
 448         target = fld_client_get_target(fld, seq);
 449         LASSERT(target != NULL);
 450
 451         CDEBUG(D_INFO, "%s: Create fld entry (seq: "LPX64"; mds: "
 452                LPU64") on target %s (idx "LPU64")\n", fld->lcf_name,
 453                seq, mds, fld_target_name(target), target->ft_idx);
 454
 455 #ifdef __KERNEL__
 456         if (target->ft_srv != NULL) {
 457                 LASSERT(env != NULL);
 458                 rc = fld_server_create(target->ft_srv,
 459                                        env, seq, mds);
 460         } else {
 461 #endif
 462                 rc = fld_client_rpc(target->ft_exp,
 463                                     &md_fld, FLD_CREATE);
 464 #ifdef __KERNEL__
 465         }
 466 #endif
 467
 468         if (rc == 0) {
 469                 /*
 470                  * Do not return result of calling fld_cache_insert()
 471                  * here. First of all because it may return -EEXISTS. Another
 472                  * reason is that, we do not want to stop proceeding because of
 473                  * cache errors.
 474                  */
 475                 fld_cache_insert(fld->lcf_cache, seq, mds);
 476         } else {
 477                 CERROR("%s: Can't create FLD entry, rc %d\n",
 478                        fld->lcf_name, rc);
 479         }
 480
 481         RETURN(rc);
 482 }
 483 EXPORT_SYMBOL(fld_client_create);
 484
 485 int fld_client_delete(struct lu_client_fld *fld, seqno_t seq,
 486                       const struct lu_env *env)
 487 {
 488         struct md_fld md_fld = { .mf_seq = seq, .mf_mds = 0 };
 489         struct lu_fld_target *target;
 490         int rc;
 491         ENTRY;
 492
 493         fld->lcf_flags |= LUSTRE_FLD_RUN;
 494         fld_cache_delete(fld->lcf_cache, seq);
 495
 496         target = fld_client_get_target(fld, seq);
 497         LASSERT(target != NULL);
 498
 499         CDEBUG(D_INFO, "%s: Delete fld entry (seq: "LPX64") on "
 500                "target %s (idx "LPU64")\n", fld->lcf_name, seq,
 501                fld_target_name(target), target->ft_idx);
 502
 503 #ifdef __KERNEL__
 504         if (target->ft_srv != NULL) {
 505                 LASSERT(env != NULL);
 506                 rc = fld_server_delete(target->ft_srv,
 507                                        env, seq);
 508         } else {
 509 #endif
 510                 rc = fld_client_rpc(target->ft_exp,
 511                                     &md_fld, FLD_DELETE);
 512 #ifdef __KERNEL__
 513         }
 514 #endif
 515
 516         RETURN(rc);
 517 }
 518 EXPORT_SYMBOL(fld_client_delete);
 519
 520 int fld_client_lookup(struct lu_client_fld *fld,
 521                       seqno_t seq, mdsno_t *mds,
 522                       const struct lu_env *env)
 523 {
 524         struct md_fld md_fld = { .mf_seq = seq, .mf_mds = 0 };
 525         struct lu_fld_target *target;
 526         int rc;
 527         ENTRY;
 528
 529         fld->lcf_flags |= LUSTRE_FLD_RUN;
 530
 531         rc = fld_cache_lookup(fld->lcf_cache, seq, mds);
 532         if (rc == 0)
 533                 RETURN(0);
 534
 535         /* Can not find it in the cache */
 536         target = fld_client_get_target(fld, seq);
 537         LASSERT(target != NULL);
 538
 539         CDEBUG(D_INFO, "%s: Lookup fld entry (seq: "LPX64") on "
 540                "target %s (idx "LPU64")\n", fld->lcf_name, seq,
 541                fld_target_name(target), target->ft_idx);
 542
 543 #ifdef __KERNEL__
 544         if (target->ft_srv != NULL) {
 545                 LASSERT(env != NULL);
 546                 rc = fld_server_lookup(target->ft_srv,
 547                                        env, seq, &md_fld.mf_mds);
 548         } else {
 549 #endif
 550                 rc = fld_client_rpc(target->ft_exp,
 551                                     &md_fld, FLD_LOOKUP);
 552 #ifdef __KERNEL__
 553         }
 554 #endif
 555         if (rc == 0) {
 556                 *mds = md_fld.mf_mds;
 557
 558                 /*
 559                  * Do not return error here as well. See previous comment in
 560                  * same situation in function fld_client_create().
 561                  */
 562                 fld_cache_insert(fld->lcf_cache, seq, *mds);
 563         }
 564         RETURN(rc);
 565 }
 566 EXPORT_SYMBOL(fld_client_lookup);