lustre/mdc/mdc_locks.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2013, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_MDC
  38
  39 #ifdef __KERNEL__
  40 # include <linux/module.h>
  41 # include <linux/lustre_intent.h>
  42 #else
  43 # include <liblustre.h>
  44 #endif
  45
  46 #include <obd.h>
  47 #include <obd_class.h>
  48 #include <lustre_dlm.h>
  49 #include <lustre_fid.h> /* fid_res_name_eq() */
  50 #include <lustre_mdc.h>
  51 #include <lustre_net.h>
  52 #include <lustre_req_layout.h>
  53 #include "mdc_internal.h"
  54
  55 struct mdc_getattr_args {
  56         struct obd_export           *ga_exp;
  57         struct md_enqueue_info      *ga_minfo;
  58         struct ldlm_enqueue_info    *ga_einfo;
  59 };
  60
  61 int it_open_error(int phase, struct lookup_intent *it)
  62 {
  63         if (it_disposition(it, DISP_OPEN_LEASE)) {
  64                 if (phase >= DISP_OPEN_LEASE)
  65                         return it->d.lustre.it_status;
  66                 else
  67                         return 0;
  68         }
  69         if (it_disposition(it, DISP_OPEN_OPEN)) {
  70                 if (phase >= DISP_OPEN_OPEN)
  71                         return it->d.lustre.it_status;
  72                 else
  73                         return 0;
  74         }
  75
  76         if (it_disposition(it, DISP_OPEN_CREATE)) {
  77                 if (phase >= DISP_OPEN_CREATE)
  78                         return it->d.lustre.it_status;
  79                 else
  80                         return 0;
  81         }
  82
  83         if (it_disposition(it, DISP_LOOKUP_EXECD)) {
  84                 if (phase >= DISP_LOOKUP_EXECD)
  85                         return it->d.lustre.it_status;
  86                 else
  87                         return 0;
  88         }
  89
  90         if (it_disposition(it, DISP_IT_EXECD)) {
  91                 if (phase >= DISP_IT_EXECD)
  92                         return it->d.lustre.it_status;
  93                 else
  94                         return 0;
  95         }
  96         CERROR("it disp: %X, status: %d\n", it->d.lustre.it_disposition,
  97                it->d.lustre.it_status);
  98         LBUG();
  99         return 0;
 100 }
 101 EXPORT_SYMBOL(it_open_error);
 102
 103 /* this must be called on a lockh that is known to have a referenced lock */
 104 int mdc_set_lock_data(struct obd_export *exp, __u64 *lockh, void *data,
 105                       __u64 *bits)
 106 {
 107         struct ldlm_lock *lock;
 108         struct inode *new_inode = data;
 109         ENTRY;
 110
 111         if(bits)
 112                 *bits = 0;
 113
 114         if (!*lockh)
 115                 RETURN(0);
 116
 117         lock = ldlm_handle2lock((struct lustre_handle *)lockh);
 118
 119         LASSERT(lock != NULL);
 120         lock_res_and_lock(lock);
 121 #ifdef __KERNEL__
 122         if (lock->l_resource->lr_lvb_inode &&
 123             lock->l_resource->lr_lvb_inode != data) {
 124                 struct inode *old_inode = lock->l_resource->lr_lvb_inode;
 125                 LASSERTF(old_inode->i_state & I_FREEING,
 126                          "Found existing inode %p/%lu/%u state %lu in lock: "
 127                          "setting data to %p/%lu/%u\n", old_inode,
 128                          old_inode->i_ino, old_inode->i_generation,
 129                          old_inode->i_state,
 130                          new_inode, new_inode->i_ino, new_inode->i_generation);
 131         }
 132 #endif
 133         lock->l_resource->lr_lvb_inode = new_inode;
 134         if (bits)
 135                 *bits = lock->l_policy_data.l_inodebits.bits;
 136
 137         unlock_res_and_lock(lock);
 138         LDLM_LOCK_PUT(lock);
 139
 140         RETURN(0);
 141 }
 142
 143 ldlm_mode_t mdc_lock_match(struct obd_export *exp, __u64 flags,
 144                            const struct lu_fid *fid, ldlm_type_t type,
 145                            ldlm_policy_data_t *policy, ldlm_mode_t mode,
 146                            struct lustre_handle *lockh)
 147 {
 148         struct ldlm_res_id res_id;
 149         ldlm_mode_t rc;
 150         ENTRY;
 151
 152         fid_build_reg_res_name(fid, &res_id);
 153         /* LU-4405: Clear bits not supported by server */
 154         policy->l_inodebits.bits &= exp_connect_ibits(exp);
 155         rc = ldlm_lock_match(class_exp2obd(exp)->obd_namespace, flags,
 156                              &res_id, type, policy, mode, lockh, 0);
 157         RETURN(rc);
 158 }
 159
 160 int mdc_cancel_unused(struct obd_export *exp,
 161                       const struct lu_fid *fid,
 162                       ldlm_policy_data_t *policy,
 163                       ldlm_mode_t mode,
 164                       ldlm_cancel_flags_t flags,
 165                       void *opaque)
 166 {
 167         struct ldlm_res_id res_id;
 168         struct obd_device *obd = class_exp2obd(exp);
 169         int rc;
 170
 171         ENTRY;
 172
 173         fid_build_reg_res_name(fid, &res_id);
 174         rc = ldlm_cli_cancel_unused_resource(obd->obd_namespace, &res_id,
 175                                              policy, mode, flags, opaque);
 176         RETURN(rc);
 177 }
 178
 179 int mdc_null_inode(struct obd_export *exp,
 180                    const struct lu_fid *fid)
 181 {
 182         struct ldlm_res_id res_id;
 183         struct ldlm_resource *res;
 184         struct ldlm_namespace *ns = class_exp2obd(exp)->obd_namespace;
 185         ENTRY;
 186
 187         LASSERTF(ns != NULL, "no namespace passed\n");
 188
 189         fid_build_reg_res_name(fid, &res_id);
 190
 191         res = ldlm_resource_get(ns, NULL, &res_id, 0, 0);
 192         if (IS_ERR(res))
 193                 RETURN(0);
 194
 195         lock_res(res);
 196         res->lr_lvb_inode = NULL;
 197         unlock_res(res);
 198
 199         ldlm_resource_putref(res);
 200         RETURN(0);
 201 }
 202
 203 /* find any ldlm lock of the inode in mdc
 204  * return 0    not find
 205  *        1    find one
 206  *      < 0    error */
 207 int mdc_find_cbdata(struct obd_export *exp,
 208                     const struct lu_fid *fid,
 209                     ldlm_iterator_t it, void *data)
 210 {
 211         struct ldlm_res_id res_id;
 212         int rc = 0;
 213         ENTRY;
 214
 215         fid_build_reg_res_name((struct lu_fid*)fid, &res_id);
 216         rc = ldlm_resource_iterate(class_exp2obd(exp)->obd_namespace, &res_id,
 217                                    it, data);
 218         if (rc == LDLM_ITER_STOP)
 219                 RETURN(1);
 220         else if (rc == LDLM_ITER_CONTINUE)
 221                 RETURN(0);
 222         RETURN(rc);
 223 }
 224
 225 static inline void mdc_clear_replay_flag(struct ptlrpc_request *req, int rc)
 226 {
 227         /* Don't hold error requests for replay. */
 228         if (req->rq_replay) {
 229                 spin_lock(&req->rq_lock);
 230                 req->rq_replay = 0;
 231                 spin_unlock(&req->rq_lock);
 232         }
 233         if (rc && req->rq_transno != 0) {
 234                 DEBUG_REQ(D_ERROR, req, "transno returned on error rc %d", rc);
 235                 LBUG();
 236         }
 237 }
 238
 239 /* Save a large LOV EA into the request buffer so that it is available
 240  * for replay.  We don't do this in the initial request because the
 241  * original request doesn't need this buffer (at most it sends just the
 242  * lov_mds_md) and it is a waste of RAM/bandwidth to send the empty
 243  * buffer and may also be difficult to allocate and save a very large
 244  * request buffer for each open. (bug 5707)
 245  *
 246  * OOM here may cause recovery failure if lmm is needed (only for the
 247  * original open if the MDS crashed just when this client also OOM'd)
 248  * but this is incredibly unlikely, and questionable whether the client
 249  * could do MDS recovery under OOM anyways... */
 250 static void mdc_realloc_openmsg(struct ptlrpc_request *req,
 251                                 struct mdt_body *body)
 252 {
 253         int     rc;
 254
 255         /* FIXME: remove this explicit offset. */
 256         rc = sptlrpc_cli_enlarge_reqbuf(req, DLM_INTENT_REC_OFF + 4,
 257                                         body->mbo_eadatasize);
 258         if (rc) {
 259                 CERROR("Can't enlarge segment %d size to %d\n",
 260                        DLM_INTENT_REC_OFF + 4, body->mbo_eadatasize);
 261                 body->mbo_valid &= ~OBD_MD_FLEASIZE;
 262                 body->mbo_eadatasize = 0;
 263         }
 264 }
 265
 266 static struct ptlrpc_request *
 267 mdc_intent_open_pack(struct obd_export *exp, struct lookup_intent *it,
 268                      struct md_op_data *op_data)
 269 {
 270         struct ptlrpc_request   *req;
 271         struct obd_device       *obddev = class_exp2obd(exp);
 272         struct ldlm_intent      *lit;
 273         const void              *lmm = op_data->op_data;
 274         int                      lmmsize = op_data->op_data_size;
 275         struct list_head         cancels = LIST_HEAD_INIT(cancels);
 276         int                      count = 0;
 277         int                      mode;
 278         int                      rc;
 279         ENTRY;
 280
 281         it->it_create_mode = (it->it_create_mode & ~S_IFMT) | S_IFREG;
 282
 283         /* XXX: openlock is not cancelled for cross-refs. */
 284         /* If inode is known, cancel conflicting OPEN locks. */
 285         if (fid_is_sane(&op_data->op_fid2)) {
 286                 if (it->it_flags & MDS_OPEN_LEASE) { /* try to get lease */
 287                         if (it->it_flags & FMODE_WRITE)
 288                                 mode = LCK_EX;
 289                         else
 290                                 mode = LCK_PR;
 291                 } else {
 292                         if (it->it_flags & (FMODE_WRITE|MDS_OPEN_TRUNC))
 293                                 mode = LCK_CW;
 294 #ifdef FMODE_EXEC
 295                         else if (it->it_flags & FMODE_EXEC)
 296                                 mode = LCK_PR;
 297 #endif
 298                         else
 299                                 mode = LCK_CR;
 300                 }
 301                 count = mdc_resource_get_unused(exp, &op_data->op_fid2,
 302                                                 &cancels, mode,
 303                                                 MDS_INODELOCK_OPEN);
 304         }
 305
 306         /* If CREATE, cancel parent's UPDATE lock. */
 307         if (it->it_op & IT_CREAT)
 308                 mode = LCK_EX;
 309         else
 310                 mode = LCK_CR;
 311         count += mdc_resource_get_unused(exp, &op_data->op_fid1,
 312                                          &cancels, mode,
 313                                          MDS_INODELOCK_UPDATE);
 314
 315         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
 316                                    &RQF_LDLM_INTENT_OPEN);
 317         if (req == NULL) {
 318                 ldlm_lock_list_put(&cancels, l_bl_ast, count);
 319                 RETURN(ERR_PTR(-ENOMEM));
 320         }
 321
 322         /* parent capability */
 323         mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
 324         /* child capability, reserve the size according to parent capa, it will
 325          * be filled after we get the reply */
 326         mdc_set_capa_size(req, &RMF_CAPA2, op_data->op_capa1);
 327
 328         req_capsule_set_size(&req->rq_pill, &RMF_NAME, RCL_CLIENT,
 329                              op_data->op_namelen + 1);
 330         req_capsule_set_size(&req->rq_pill, &RMF_EADATA, RCL_CLIENT,
 331                              max(lmmsize, obddev->u.cli.cl_default_mds_easize));
 332
 333         rc = ldlm_prep_enqueue_req(exp, req, &cancels, count);
 334         if (rc < 0) {
 335                 ptlrpc_request_free(req);
 336                 RETURN(ERR_PTR(rc));
 337         }
 338
 339         spin_lock(&req->rq_lock);
 340         req->rq_replay = req->rq_import->imp_replayable;
 341         spin_unlock(&req->rq_lock);
 342
 343         /* pack the intent */
 344         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
 345         lit->opc = (__u64)it->it_op;
 346
 347         /* pack the intended request */
 348         mdc_open_pack(req, op_data, it->it_create_mode, 0, it->it_flags, lmm,
 349                       lmmsize);
 350
 351         req_capsule_set_size(&req->rq_pill, &RMF_MDT_MD, RCL_SERVER,
 352                              obddev->u.cli.cl_max_mds_easize);
 353
 354         /* for remote client, fetch remote perm for current user */
 355         if (client_is_remote(exp))
 356                 req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER,
 357                                      sizeof(struct mdt_remote_perm));
 358         ptlrpc_request_set_replen(req);
 359         return req;
 360 }
 361
 362 static struct ptlrpc_request *
 363 mdc_intent_getxattr_pack(struct obd_export *exp,
 364                          struct lookup_intent *it,
 365                          struct md_op_data *op_data)
 366 {
 367         struct ptlrpc_request   *req;
 368         struct ldlm_intent      *lit;
 369         int                     rc, count = 0, maxdata;
 370         struct list_head        cancels = LIST_HEAD_INIT(cancels);
 371
 372         ENTRY;
 373
 374         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
 375                                         &RQF_LDLM_INTENT_GETXATTR);
 376         if (req == NULL)
 377                 RETURN(ERR_PTR(-ENOMEM));
 378
 379         mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
 380
 381         rc = ldlm_prep_enqueue_req(exp, req, &cancels, count);
 382         if (rc) {
 383                 ptlrpc_request_free(req);
 384                 RETURN(ERR_PTR(rc));
 385         }
 386
 387         /* pack the intent */
 388         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
 389         lit->opc = IT_GETXATTR;
 390
 391         maxdata = class_exp2cliimp(exp)->imp_connect_data.ocd_max_easize;
 392
 393         /* pack the intended request */
 394         mdc_pack_body(req, &op_data->op_fid1, op_data->op_capa1,
 395                         op_data->op_valid, maxdata, -1, 0);
 396
 397         req_capsule_set_size(&req->rq_pill, &RMF_EADATA,
 398                                 RCL_SERVER, maxdata);
 399
 400         req_capsule_set_size(&req->rq_pill, &RMF_EAVALS,
 401                                 RCL_SERVER, maxdata);
 402
 403         req_capsule_set_size(&req->rq_pill, &RMF_EAVALS_LENS,
 404                                 RCL_SERVER, maxdata);
 405
 406         ptlrpc_request_set_replen(req);
 407
 408         RETURN(req);
 409 }
 410
 411 static struct ptlrpc_request *mdc_intent_unlink_pack(struct obd_export *exp,
 412                                                      struct lookup_intent *it,
 413                                                      struct md_op_data *op_data)
 414 {
 415         struct ptlrpc_request *req;
 416         struct obd_device     *obddev = class_exp2obd(exp);
 417         struct ldlm_intent    *lit;
 418         int                    rc;
 419         ENTRY;
 420
 421         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
 422                                    &RQF_LDLM_INTENT_UNLINK);
 423         if (req == NULL)
 424                 RETURN(ERR_PTR(-ENOMEM));
 425
 426         mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
 427         req_capsule_set_size(&req->rq_pill, &RMF_NAME, RCL_CLIENT,
 428                              op_data->op_namelen + 1);
 429
 430         rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
 431         if (rc) {
 432                 ptlrpc_request_free(req);
 433                 RETURN(ERR_PTR(rc));
 434         }
 435
 436         /* pack the intent */
 437         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
 438         lit->opc = (__u64)it->it_op;
 439
 440         /* pack the intended request */
 441         mdc_unlink_pack(req, op_data);
 442
 443         req_capsule_set_size(&req->rq_pill, &RMF_MDT_MD, RCL_SERVER,
 444                              obddev->u.cli.cl_default_mds_easize);
 445         req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER,
 446                              obddev->u.cli.cl_default_mds_cookiesize);
 447         ptlrpc_request_set_replen(req);
 448         RETURN(req);
 449 }
 450
 451 static struct ptlrpc_request *mdc_intent_getattr_pack(struct obd_export *exp,
 452                                                       struct lookup_intent *it,
 453                                                       struct md_op_data *op_data)
 454 {
 455         struct ptlrpc_request *req;
 456         struct obd_device     *obddev = class_exp2obd(exp);
 457         obd_valid              valid = OBD_MD_FLGETATTR | OBD_MD_FLEASIZE |
 458                                        OBD_MD_FLMODEASIZE | OBD_MD_FLDIREA |
 459                                        OBD_MD_FLMDSCAPA | OBD_MD_MEA |
 460                                        (client_is_remote(exp) ?
 461                                                OBD_MD_FLRMTPERM : OBD_MD_FLACL);
 462         struct ldlm_intent    *lit;
 463         int                    rc;
 464         int                     easize;
 465         ENTRY;
 466
 467         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
 468                                    &RQF_LDLM_INTENT_GETATTR);
 469         if (req == NULL)
 470                 RETURN(ERR_PTR(-ENOMEM));
 471
 472         mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
 473         req_capsule_set_size(&req->rq_pill, &RMF_NAME, RCL_CLIENT,
 474                              op_data->op_namelen + 1);
 475
 476         rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
 477         if (rc) {
 478                 ptlrpc_request_free(req);
 479                 RETURN(ERR_PTR(rc));
 480         }
 481
 482         /* pack the intent */
 483         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
 484         lit->opc = (__u64)it->it_op;
 485
 486         if (obddev->u.cli.cl_default_mds_easize > 0)
 487                 easize = obddev->u.cli.cl_default_mds_easize;
 488         else
 489                 easize = obddev->u.cli.cl_max_mds_easize;
 490
 491         /* pack the intended request */
 492         mdc_getattr_pack(req, valid, it->it_flags, op_data, easize);
 493
 494         req_capsule_set_size(&req->rq_pill, &RMF_MDT_MD, RCL_SERVER, easize);
 495         if (client_is_remote(exp))
 496                 req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER,
 497                                      sizeof(struct mdt_remote_perm));
 498         ptlrpc_request_set_replen(req);
 499         RETURN(req);
 500 }
 501
 502 static struct ptlrpc_request *mdc_intent_layout_pack(struct obd_export *exp,
 503                                                      struct lookup_intent *it,
 504                                                      struct md_op_data *unused)
 505 {
 506         struct obd_device     *obd = class_exp2obd(exp);
 507         struct ptlrpc_request *req;
 508         struct ldlm_intent    *lit;
 509         struct layout_intent  *layout;
 510         int rc;
 511         ENTRY;
 512
 513         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
 514                                 &RQF_LDLM_INTENT_LAYOUT);
 515         if (req == NULL)
 516                 RETURN(ERR_PTR(-ENOMEM));
 517
 518         req_capsule_set_size(&req->rq_pill, &RMF_EADATA, RCL_CLIENT, 0);
 519         rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
 520         if (rc) {
 521                 ptlrpc_request_free(req);
 522                 RETURN(ERR_PTR(rc));
 523         }
 524
 525         /* pack the intent */
 526         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
 527         lit->opc = (__u64)it->it_op;
 528
 529         /* pack the layout intent request */
 530         layout = req_capsule_client_get(&req->rq_pill, &RMF_LAYOUT_INTENT);
 531         /* LAYOUT_INTENT_ACCESS is generic, specific operation will be
 532          * set for replication */
 533         layout->li_opc = LAYOUT_INTENT_ACCESS;
 534
 535         req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER,
 536                              obd->u.cli.cl_default_mds_easize);
 537         ptlrpc_request_set_replen(req);
 538         RETURN(req);
 539 }
 540
 541 static struct ptlrpc_request *
 542 mdc_enqueue_pack(struct obd_export *exp, int lvb_len)
 543 {
 544         struct ptlrpc_request *req;
 545         int rc;
 546         ENTRY;
 547
 548         req = ptlrpc_request_alloc(class_exp2cliimp(exp), &RQF_LDLM_ENQUEUE);
 549         if (req == NULL)
 550                 RETURN(ERR_PTR(-ENOMEM));
 551
 552         rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
 553         if (rc) {
 554                 ptlrpc_request_free(req);
 555                 RETURN(ERR_PTR(rc));
 556         }
 557
 558         req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER, lvb_len);
 559         ptlrpc_request_set_replen(req);
 560         RETURN(req);
 561 }
 562
 563 static int mdc_finish_enqueue(struct obd_export *exp,
 564                               struct ptlrpc_request *req,
 565                               struct ldlm_enqueue_info *einfo,
 566                               struct lookup_intent *it,
 567                               struct lustre_handle *lockh,
 568                               int rc)
 569 {
 570         struct req_capsule  *pill = &req->rq_pill;
 571         struct ldlm_request *lockreq;
 572         struct ldlm_reply   *lockrep;
 573         struct lustre_intent_data *intent = &it->d.lustre;
 574         struct ldlm_lock    *lock;
 575         void                *lvb_data = NULL;
 576         int                  lvb_len = 0;
 577         ENTRY;
 578
 579         LASSERT(rc >= 0);
 580         /* Similarly, if we're going to replay this request, we don't want to
 581          * actually get a lock, just perform the intent. */
 582         if (req->rq_transno || req->rq_replay) {
 583                 lockreq = req_capsule_client_get(pill, &RMF_DLM_REQ);
 584                 lockreq->lock_flags |= ldlm_flags_to_wire(LDLM_FL_INTENT_ONLY);
 585         }
 586
 587         if (rc == ELDLM_LOCK_ABORTED) {
 588                 einfo->ei_mode = 0;
 589                 memset(lockh, 0, sizeof(*lockh));
 590                 rc = 0;
 591         } else { /* rc = 0 */
 592                 lock = ldlm_handle2lock(lockh);
 593                 LASSERT(lock != NULL);
 594
 595                 /* If the server gave us back a different lock mode, we should
 596                  * fix up our variables. */
 597                 if (lock->l_req_mode != einfo->ei_mode) {
 598                         ldlm_lock_addref(lockh, lock->l_req_mode);
 599                         ldlm_lock_decref(lockh, einfo->ei_mode);
 600                         einfo->ei_mode = lock->l_req_mode;
 601                 }
 602                 LDLM_LOCK_PUT(lock);
 603         }
 604
 605         lockrep = req_capsule_server_get(pill, &RMF_DLM_REP);
 606         LASSERT(lockrep != NULL); /* checked by ldlm_cli_enqueue() */
 607
 608         intent->it_disposition = (int)lockrep->lock_policy_res1;
 609         intent->it_status = (int)lockrep->lock_policy_res2;
 610         intent->it_lock_mode = einfo->ei_mode;
 611         intent->it_lock_handle = lockh->cookie;
 612         intent->it_data = req;
 613
 614         /* Technically speaking rq_transno must already be zero if
 615          * it_status is in error, so the check is a bit redundant */
 616         if ((!req->rq_transno || intent->it_status < 0) && req->rq_replay)
 617                 mdc_clear_replay_flag(req, intent->it_status);
 618
 619         /* If we're doing an IT_OPEN which did not result in an actual
 620          * successful open, then we need to remove the bit which saves
 621          * this request for unconditional replay.
 622          *
 623          * It's important that we do this first!  Otherwise we might exit the
 624          * function without doing so, and try to replay a failed create
 625          * (bug 3440) */
 626         if (it->it_op & IT_OPEN && req->rq_replay &&
 627             (!it_disposition(it, DISP_OPEN_OPEN) ||intent->it_status != 0))
 628                 mdc_clear_replay_flag(req, intent->it_status);
 629
 630         DEBUG_REQ(D_RPCTRACE, req, "op: %d disposition: %x, status: %d",
 631                   it->it_op, intent->it_disposition, intent->it_status);
 632
 633         /* We know what to expect, so we do any byte flipping required here */
 634         if (it->it_op & (IT_OPEN | IT_UNLINK | IT_LOOKUP | IT_GETATTR)) {
 635                 struct mdt_body *body;
 636
 637                 body = req_capsule_server_get(pill, &RMF_MDT_BODY);
 638                 if (body == NULL) {
 639                         CERROR ("Can't swab mdt_body\n");
 640                         RETURN (-EPROTO);
 641                 }
 642
 643                 if (it_disposition(it, DISP_OPEN_OPEN) &&
 644                     !it_open_error(DISP_OPEN_OPEN, it)) {
 645                         /*
 646                          * If this is a successful OPEN request, we need to set
 647                          * replay handler and data early, so that if replay
 648                          * happens immediately after swabbing below, new reply
 649                          * is swabbed by that handler correctly.
 650                          */
 651                         mdc_set_open_replay_data(NULL, NULL, it);
 652                 }
 653
 654                 if (body->mbo_valid & (OBD_MD_FLDIREA | OBD_MD_FLEASIZE)) {
 655                         void *eadata;
 656
 657                         mdc_update_max_ea_from_body(exp, body);
 658
 659                         /*
 660                          * The eadata is opaque; just check that it is there.
 661                          * Eventually, obd_unpackmd() will check the contents.
 662                          */
 663                         eadata = req_capsule_server_sized_get(pill, &RMF_MDT_MD,
 664                                                         body->mbo_eadatasize);
 665                         if (eadata == NULL)
 666                                 RETURN(-EPROTO);
 667
 668                         /* save lvb data and length in case this is for layout
 669                          * lock */
 670                         lvb_data = eadata;
 671                         lvb_len = body->mbo_eadatasize;
 672
 673                         /*
 674                          * We save the reply LOV EA in case we have to replay a
 675                          * create for recovery.  If we didn't allocate a large
 676                          * enough request buffer above we need to reallocate it
 677                          * here to hold the actual LOV EA.
 678                          *
 679                          * To not save LOV EA if request is not going to replay
 680                          * (for example error one).
 681                          */
 682                         if ((it->it_op & IT_OPEN) && req->rq_replay) {
 683                                 void *lmm;
 684                                 if (req_capsule_get_size(pill, &RMF_EADATA,
 685                                                          RCL_CLIENT) <
 686                                     body->mbo_eadatasize)
 687                                         mdc_realloc_openmsg(req, body);
 688                                 else
 689                                         req_capsule_shrink(pill, &RMF_EADATA,
 690                                                            body->mbo_eadatasize,
 691                                                            RCL_CLIENT);
 692
 693                                 req_capsule_set_size(pill, &RMF_EADATA,
 694                                                      RCL_CLIENT,
 695                                                      body->mbo_eadatasize);
 696
 697                                 lmm = req_capsule_client_get(pill, &RMF_EADATA);
 698                                 if (lmm)
 699                                         memcpy(lmm, eadata,
 700                                                body->mbo_eadatasize);
 701                         }
 702                 }
 703
 704                 if (body->mbo_valid & OBD_MD_FLRMTPERM) {
 705                         struct mdt_remote_perm *perm;
 706
 707                         LASSERT(client_is_remote(exp));
 708                         perm = req_capsule_server_swab_get(pill, &RMF_ACL,
 709                                                 lustre_swab_mdt_remote_perm);
 710                         if (perm == NULL)
 711                                 RETURN(-EPROTO);
 712                 }
 713                 if (body->mbo_valid & OBD_MD_FLMDSCAPA) {
 714                         struct lustre_capa *capa, *p;
 715
 716                         capa = req_capsule_server_get(pill, &RMF_CAPA1);
 717                         if (capa == NULL)
 718                                 RETURN(-EPROTO);
 719
 720                         if (it->it_op & IT_OPEN) {
 721                                 /* client fid capa will be checked in replay */
 722                                 p = req_capsule_client_get(pill, &RMF_CAPA2);
 723                                 LASSERT(p);
 724                                 *p = *capa;
 725                         }
 726                 }
 727                 if (body->mbo_valid & OBD_MD_FLOSSCAPA) {
 728                         struct lustre_capa *capa;
 729
 730                         capa = req_capsule_server_get(pill, &RMF_CAPA2);
 731                         if (capa == NULL)
 732                                 RETURN(-EPROTO);
 733                 }
 734         } else if (it->it_op & IT_LAYOUT) {
 735                 /* maybe the lock was granted right away and layout
 736                  * is packed into RMF_DLM_LVB of req */
 737                 lvb_len = req_capsule_get_size(pill, &RMF_DLM_LVB, RCL_SERVER);
 738                 if (lvb_len > 0) {
 739                         lvb_data = req_capsule_server_sized_get(pill,
 740                                                         &RMF_DLM_LVB, lvb_len);
 741                         if (lvb_data == NULL)
 742                                 RETURN(-EPROTO);
 743                 }
 744         }
 745
 746         /* fill in stripe data for layout lock */
 747         lock = ldlm_handle2lock(lockh);
 748         if (lock != NULL && ldlm_has_layout(lock) && lvb_data != NULL) {
 749                 void *lmm;
 750
 751                 LDLM_DEBUG(lock, "layout lock returned by: %s, lvb_len: %d\n",
 752                         ldlm_it2str(it->it_op), lvb_len);
 753
 754                 OBD_ALLOC_LARGE(lmm, lvb_len);
 755                 if (lmm == NULL) {
 756                         LDLM_LOCK_PUT(lock);
 757                         RETURN(-ENOMEM);
 758                 }
 759                 memcpy(lmm, lvb_data, lvb_len);
 760
 761                 /* install lvb_data */
 762                 lock_res_and_lock(lock);
 763                 if (lock->l_lvb_data == NULL) {
 764                         lock->l_lvb_type = LVB_T_LAYOUT;
 765                         lock->l_lvb_data = lmm;
 766                         lock->l_lvb_len = lvb_len;
 767                         lmm = NULL;
 768                 }
 769                 unlock_res_and_lock(lock);
 770                 if (lmm != NULL)
 771                         OBD_FREE_LARGE(lmm, lvb_len);
 772         }
 773         if (lock != NULL)
 774                 LDLM_LOCK_PUT(lock);
 775
 776         RETURN(rc);
 777 }
 778
 779 /* We always reserve enough space in the reply packet for a stripe MD, because
 780  * we don't know in advance the file type. */
 781 int mdc_enqueue(struct obd_export *exp,
 782                 struct ldlm_enqueue_info *einfo,
 783                 const union ldlm_policy_data *policy,
 784                 struct lookup_intent *it, struct md_op_data *op_data,
 785                 struct lustre_handle *lockh, __u64 extra_lock_flags)
 786 {
 787         struct obd_device     *obddev = class_exp2obd(exp);
 788         struct ptlrpc_request *req = NULL;
 789         __u64                  flags, saved_flags = extra_lock_flags;
 790         int                    rc;
 791         struct ldlm_res_id res_id;
 792         static const ldlm_policy_data_t lookup_policy =
 793                             { .l_inodebits = { MDS_INODELOCK_LOOKUP } };
 794         static const ldlm_policy_data_t update_policy =
 795                             { .l_inodebits = { MDS_INODELOCK_UPDATE } };
 796         static const ldlm_policy_data_t layout_policy =
 797                             { .l_inodebits = { MDS_INODELOCK_LAYOUT } };
 798         static const ldlm_policy_data_t getxattr_policy = {
 799                               .l_inodebits = { MDS_INODELOCK_XATTR } };
 800         int                    generation, resends = 0;
 801         struct ldlm_reply     *lockrep;
 802         enum lvb_type          lvb_type = 0;
 803         ENTRY;
 804
 805         LASSERTF(!it || einfo->ei_type == LDLM_IBITS, "lock type %d\n",
 806                  einfo->ei_type);
 807         fid_build_reg_res_name(&op_data->op_fid1, &res_id);
 808
 809         if (it != NULL) {
 810                 LASSERT(policy == NULL);
 811
 812                 saved_flags |= LDLM_FL_HAS_INTENT;
 813                 if (it->it_op & (IT_OPEN | IT_UNLINK | IT_GETATTR | IT_READDIR))
 814                         policy = &update_policy;
 815                 else if (it->it_op & IT_LAYOUT)
 816                         policy = &layout_policy;
 817                 else if (it->it_op & (IT_GETXATTR | IT_SETXATTR))
 818                         policy = &getxattr_policy;
 819                 else
 820                         policy = &lookup_policy;
 821         }
 822
 823         generation = obddev->u.cli.cl_import->imp_generation;
 824 resend:
 825         flags = saved_flags;
 826         if (it == NULL) {
 827                 /* The only way right now is FLOCK. */
 828                 LASSERTF(einfo->ei_type == LDLM_FLOCK, "lock type %d\n",
 829                          einfo->ei_type);
 830                 res_id.name[3] = LDLM_FLOCK;
 831         } else if (it->it_op & IT_OPEN) {
 832                 req = mdc_intent_open_pack(exp, it, op_data);
 833         } else if (it->it_op & IT_UNLINK) {
 834                 req = mdc_intent_unlink_pack(exp, it, op_data);
 835         } else if (it->it_op & (IT_GETATTR | IT_LOOKUP)) {
 836                 req = mdc_intent_getattr_pack(exp, it, op_data);
 837         } else if (it->it_op & IT_READDIR) {
 838                 req = mdc_enqueue_pack(exp, 0);
 839         } else if (it->it_op & IT_LAYOUT) {
 840                 if (!imp_connect_lvb_type(class_exp2cliimp(exp)))
 841                         RETURN(-EOPNOTSUPP);
 842                 req = mdc_intent_layout_pack(exp, it, op_data);
 843                 lvb_type = LVB_T_LAYOUT;
 844         } else if (it->it_op & IT_GETXATTR) {
 845                 req = mdc_intent_getxattr_pack(exp, it, op_data);
 846         } else {
 847                 LBUG();
 848                 RETURN(-EINVAL);
 849         }
 850
 851         if (IS_ERR(req))
 852                 RETURN(PTR_ERR(req));
 853
 854         if (req != NULL && it && it->it_op & IT_CREAT)
 855                 /* ask ptlrpc not to resend on EINPROGRESS since we have our own
 856                  * retry logic */
 857                 req->rq_no_retry_einprogress = 1;
 858
 859         if (resends) {
 860                 req->rq_generation_set = 1;
 861                 req->rq_import_generation = generation;
 862                 req->rq_sent = cfs_time_current_sec() + resends;
 863         }
 864
 865         /* It is important to obtain rpc_lock first (if applicable), so that
 866          * threads that are serialised with rpc_lock are not polluting our
 867          * rpcs in flight counter. We do not do flock request limiting, though*/
 868         if (it) {
 869                 mdc_get_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
 870                 rc = obd_get_request_slot(&obddev->u.cli);
 871                 if (rc != 0) {
 872                         mdc_put_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
 873                         mdc_clear_replay_flag(req, 0);
 874                         ptlrpc_req_finished(req);
 875                         RETURN(rc);
 876                 }
 877         }
 878
 879         rc = ldlm_cli_enqueue(exp, &req, einfo, &res_id, policy, &flags, NULL,
 880                               0, lvb_type, lockh, 0);
 881         if (!it) {
 882                 /* For flock requests we immediatelly return without further
 883                    delay and let caller deal with the rest, since rest of
 884                    this function metadata processing makes no sense for flock
 885                    requests anyway. But in case of problem during comms with
 886                    Server (ETIMEDOUT) or any signal/kill attempt (EINTR), we
 887                    can not rely on caller and this mainly for F_UNLCKs
 888                    (explicits or automatically generated by Kernel to clean
 889                    current FLocks upon exit) that can't be trashed */
 890                 if (((rc == -EINTR) || (rc == -ETIMEDOUT)) &&
 891                     (einfo->ei_type == LDLM_FLOCK) &&
 892                     (einfo->ei_mode == LCK_NL))
 893                         goto resend;
 894                 RETURN(rc);
 895         }
 896
 897         obd_put_request_slot(&obddev->u.cli);
 898         mdc_put_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
 899
 900         if (rc < 0) {
 901                 CDEBUG(D_INFO, "%s: ldlm_cli_enqueue failed: rc = %d\n",
 902                        obddev->obd_name, rc);
 903
 904                 mdc_clear_replay_flag(req, rc);
 905                 ptlrpc_req_finished(req);
 906                 RETURN(rc);
 907         }
 908
 909         lockrep = req_capsule_server_get(&req->rq_pill, &RMF_DLM_REP);
 910         LASSERT(lockrep != NULL);
 911
 912         lockrep->lock_policy_res2 =
 913                 ptlrpc_status_ntoh(lockrep->lock_policy_res2);
 914
 915         /* Retry the create infinitely when we get -EINPROGRESS from
 916          * server. This is required by the new quota design. */
 917         if (it && it->it_op & IT_CREAT &&
 918             (int)lockrep->lock_policy_res2 == -EINPROGRESS) {
 919                 mdc_clear_replay_flag(req, rc);
 920                 ptlrpc_req_finished(req);
 921                 resends++;
 922
 923                 CDEBUG(D_HA, "%s: resend:%d op:%d "DFID"/"DFID"\n",
 924                        obddev->obd_name, resends, it->it_op,
 925                        PFID(&op_data->op_fid1), PFID(&op_data->op_fid2));
 926
 927                 if (generation == obddev->u.cli.cl_import->imp_generation) {
 928                         goto resend;
 929                 } else {
 930                         CDEBUG(D_HA, "resend cross eviction\n");
 931                         RETURN(-EIO);
 932                 }
 933         }
 934
 935         rc = mdc_finish_enqueue(exp, req, einfo, it, lockh, rc);
 936         if (rc < 0) {
 937                 if (lustre_handle_is_used(lockh)) {
 938                         ldlm_lock_decref(lockh, einfo->ei_mode);
 939                         memset(lockh, 0, sizeof(*lockh));
 940                 }
 941                 ptlrpc_req_finished(req);
 942
 943                 it->d.lustre.it_lock_handle = 0;
 944                 it->d.lustre.it_lock_mode = 0;
 945                 it->d.lustre.it_data = NULL;
 946         }
 947
 948         RETURN(rc);
 949 }
 950
 951 static int mdc_finish_intent_lock(struct obd_export *exp,
 952                                   struct ptlrpc_request *request,
 953                                   struct md_op_data *op_data,
 954                                   struct lookup_intent *it,
 955                                   struct lustre_handle *lockh)
 956 {
 957         struct lustre_handle old_lock;
 958         struct mdt_body *mdt_body;
 959         struct ldlm_lock *lock;
 960         int rc;
 961         ENTRY;
 962
 963         LASSERT(request != NULL);
 964         LASSERT(request != LP_POISON);
 965         LASSERT(request->rq_repmsg != LP_POISON);
 966
 967         if (it->it_op & IT_READDIR)
 968                 RETURN(0);
 969
 970         if (!it_disposition(it, DISP_IT_EXECD)) {
 971                 /* The server failed before it even started executing the
 972                  * intent, i.e. because it couldn't unpack the request. */
 973                 LASSERT(it->d.lustre.it_status != 0);
 974                 RETURN(it->d.lustre.it_status);
 975         }
 976         rc = it_open_error(DISP_IT_EXECD, it);
 977         if (rc)
 978                 RETURN(rc);
 979
 980         mdt_body = req_capsule_server_get(&request->rq_pill, &RMF_MDT_BODY);
 981         LASSERT(mdt_body != NULL);      /* mdc_enqueue checked */
 982
 983         rc = it_open_error(DISP_LOOKUP_EXECD, it);
 984         if (rc)
 985                 RETURN(rc);
 986
 987         /* keep requests around for the multiple phases of the call
 988          * this shows the DISP_XX must guarantee we make it into the call
 989          */
 990         if (!it_disposition(it, DISP_ENQ_CREATE_REF) &&
 991             it_disposition(it, DISP_OPEN_CREATE) &&
 992             !it_open_error(DISP_OPEN_CREATE, it)) {
 993                 it_set_disposition(it, DISP_ENQ_CREATE_REF);
 994                 ptlrpc_request_addref(request); /* balanced in ll_create_node */
 995         }
 996         if (!it_disposition(it, DISP_ENQ_OPEN_REF) &&
 997             it_disposition(it, DISP_OPEN_OPEN) &&
 998             !it_open_error(DISP_OPEN_OPEN, it)) {
 999                 it_set_disposition(it, DISP_ENQ_OPEN_REF);
1000                 ptlrpc_request_addref(request); /* balanced in ll_file_open */
1001                 /* BUG 11546 - eviction in the middle of open rpc processing */
1002                 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_ENQUEUE_PAUSE, obd_timeout);
1003         }
1004
1005         if (it->it_op & IT_CREAT) {
1006                 /* XXX this belongs in ll_create_it */
1007         } else if (it->it_op == IT_OPEN) {
1008                 LASSERT(!it_disposition(it, DISP_OPEN_CREATE));
1009         } else {
1010                 LASSERT(it->it_op & (IT_GETATTR | IT_LOOKUP | IT_LAYOUT));
1011         }
1012
1013         /* If we already have a matching lock, then cancel the new
1014          * one.  We have to set the data here instead of in
1015          * mdc_enqueue, because we need to use the child's inode as
1016          * the l_ast_data to match, and that's not available until
1017          * intent_finish has performed the iget().) */
1018         lock = ldlm_handle2lock(lockh);
1019         if (lock) {
1020                 ldlm_policy_data_t policy = lock->l_policy_data;
1021                 LDLM_DEBUG(lock, "matching against this");
1022
1023                 LASSERTF(fid_res_name_eq(&mdt_body->mbo_fid1,
1024                                          &lock->l_resource->lr_name),
1025                          "Lock res_id: "DLDLMRES", fid: "DFID"\n",
1026                          PLDLMRES(lock->l_resource), PFID(&mdt_body->mbo_fid1));
1027                 LDLM_LOCK_PUT(lock);
1028
1029                 memcpy(&old_lock, lockh, sizeof(*lockh));
1030                 if (ldlm_lock_match(NULL, LDLM_FL_BLOCK_GRANTED, NULL,
1031                                     LDLM_IBITS, &policy, LCK_NL, &old_lock, 0)) {
1032                         ldlm_lock_decref_and_cancel(lockh,
1033                                                     it->d.lustre.it_lock_mode);
1034                         memcpy(lockh, &old_lock, sizeof(old_lock));
1035                         it->d.lustre.it_lock_handle = lockh->cookie;
1036                 }
1037         }
1038         CDEBUG(D_DENTRY,"D_IT dentry %.*s intent: %s status %d disp %x rc %d\n",
1039                op_data->op_namelen, op_data->op_name, ldlm_it2str(it->it_op),
1040                it->d.lustre.it_status, it->d.lustre.it_disposition, rc);
1041         RETURN(rc);
1042 }
1043
1044 int mdc_revalidate_lock(struct obd_export *exp, struct lookup_intent *it,
1045                         struct lu_fid *fid, __u64 *bits)
1046 {
1047         /* We could just return 1 immediately, but since we should only
1048          * be called in revalidate_it if we already have a lock, let's
1049          * verify that. */
1050         struct ldlm_res_id res_id;
1051         struct lustre_handle lockh;
1052         ldlm_policy_data_t policy;
1053         ldlm_mode_t mode;
1054         ENTRY;
1055
1056         if (it->d.lustre.it_lock_handle) {
1057                 lockh.cookie = it->d.lustre.it_lock_handle;
1058                 mode = ldlm_revalidate_lock_handle(&lockh, bits);
1059         } else {
1060                 fid_build_reg_res_name(fid, &res_id);
1061                 switch (it->it_op) {
1062                 case IT_GETATTR:
1063                         /* File attributes are held under multiple bits:
1064                          * nlink is under lookup lock, size and times are
1065                          * under UPDATE lock and recently we've also got
1066                          * a separate permissions lock for owner/group/acl that
1067                          * were protected by lookup lock before.
1068                          * Getattr must provide all of that information,
1069                          * so we need to ensure we have all of those locks.
1070                          * Unfortunately, if the bits are split across multiple
1071                          * locks, there's no easy way to match all of them here,
1072                          * so an extra RPC would be performed to fetch all
1073                          * of those bits at once for now. */
1074                         /* For new MDTs(> 2.4), UPDATE|PERM should be enough,
1075                          * but for old MDTs (< 2.4), permission is covered
1076                          * by LOOKUP lock, so it needs to match all bits here.*/
1077                         policy.l_inodebits.bits = MDS_INODELOCK_UPDATE |
1078                                                   MDS_INODELOCK_LOOKUP |
1079                                                   MDS_INODELOCK_PERM;
1080                         break;
1081                 case IT_READDIR:
1082                         policy.l_inodebits.bits = MDS_INODELOCK_UPDATE;
1083                         break;
1084                 case IT_LAYOUT:
1085                         policy.l_inodebits.bits = MDS_INODELOCK_LAYOUT;
1086                         break;
1087                 default:
1088                         policy.l_inodebits.bits = MDS_INODELOCK_LOOKUP;
1089                         break;
1090                 }
1091
1092                 mode = mdc_lock_match(exp, LDLM_FL_BLOCK_GRANTED, fid,
1093                                       LDLM_IBITS, &policy,
1094                                       LCK_CR | LCK_CW | LCK_PR | LCK_PW,
1095                                       &lockh);
1096         }
1097
1098         if (mode) {
1099                 it->d.lustre.it_lock_handle = lockh.cookie;
1100                 it->d.lustre.it_lock_mode = mode;
1101         } else {
1102                 it->d.lustre.it_lock_handle = 0;
1103                 it->d.lustre.it_lock_mode = 0;
1104         }
1105
1106         RETURN(!!mode);
1107 }
1108
1109 /*
1110  * This long block is all about fixing up the lock and request state
1111  * so that it is correct as of the moment _before_ the operation was
1112  * applied; that way, the VFS will think that everything is normal and
1113  * call Lustre's regular VFS methods.
1114  *
1115  * If we're performing a creation, that means that unless the creation
1116  * failed with EEXIST, we should fake up a negative dentry.
1117  *
1118  * For everything else, we want to lookup to succeed.
1119  *
1120  * One additional note: if CREATE or OPEN succeeded, we add an extra
1121  * reference to the request because we need to keep it around until
1122  * ll_create/ll_open gets called.
1123  *
1124  * The server will return to us, in it_disposition, an indication of
1125  * exactly what d.lustre.it_status refers to.
1126  *
1127  * If DISP_OPEN_OPEN is set, then d.lustre.it_status refers to the open() call,
1128  * otherwise if DISP_OPEN_CREATE is set, then it status is the
1129  * creation failure mode.  In either case, one of DISP_LOOKUP_NEG or
1130  * DISP_LOOKUP_POS will be set, indicating whether the child lookup
1131  * was successful.
1132  *
1133  * Else, if DISP_LOOKUP_EXECD then d.lustre.it_status is the rc of the
1134  * child lookup.
1135  */
1136 int mdc_intent_lock(struct obd_export *exp, struct md_op_data *op_data,
1137                     struct lookup_intent *it, struct ptlrpc_request **reqp,
1138                     ldlm_blocking_callback cb_blocking, __u64 extra_lock_flags)
1139 {
1140         struct ldlm_enqueue_info einfo = {
1141                 .ei_type        = LDLM_IBITS,
1142                 .ei_mode        = it_to_lock_mode(it),
1143                 .ei_cb_bl       = cb_blocking,
1144                 .ei_cb_cp       = ldlm_completion_ast,
1145         };
1146         struct lustre_handle lockh;
1147         int rc = 0;
1148         ENTRY;
1149         LASSERT(it);
1150
1151         CDEBUG(D_DLMTRACE, "(name: %.*s,"DFID") in obj "DFID
1152                 ", intent: %s flags %#"LPF64"o\n", op_data->op_namelen,
1153                 op_data->op_name, PFID(&op_data->op_fid2),
1154                 PFID(&op_data->op_fid1), ldlm_it2str(it->it_op),
1155                 it->it_flags);
1156
1157         lockh.cookie = 0;
1158         if (fid_is_sane(&op_data->op_fid2) &&
1159             (it->it_op & (IT_LOOKUP | IT_GETATTR | IT_READDIR))) {
1160                 /* We could just return 1 immediately, but since we should only
1161                  * be called in revalidate_it if we already have a lock, let's
1162                  * verify that. */
1163                 it->d.lustre.it_lock_handle = 0;
1164                 rc = mdc_revalidate_lock(exp, it, &op_data->op_fid2, NULL);
1165                 /* Only return failure if it was not GETATTR by cfid
1166                    (from inode_revalidate) */
1167                 if (rc || op_data->op_namelen != 0)
1168                         RETURN(rc);
1169         }
1170
1171         /* For case if upper layer did not alloc fid, do it now. */
1172         if (!fid_is_sane(&op_data->op_fid2) && it->it_op & IT_CREAT) {
1173                 rc = mdc_fid_alloc(NULL, exp, &op_data->op_fid2, op_data);
1174                 if (rc < 0) {
1175                         CERROR("Can't alloc new fid, rc %d\n", rc);
1176                         RETURN(rc);
1177                 }
1178         }
1179
1180         rc = mdc_enqueue(exp, &einfo, NULL, it, op_data, &lockh,
1181                          extra_lock_flags);
1182         if (rc < 0)
1183                 RETURN(rc);
1184
1185         *reqp = it->d.lustre.it_data;
1186         rc = mdc_finish_intent_lock(exp, *reqp, op_data, it, &lockh);
1187         RETURN(rc);
1188 }
1189
1190 static int mdc_intent_getattr_async_interpret(const struct lu_env *env,
1191                                               struct ptlrpc_request *req,
1192                                               void *args, int rc)
1193 {
1194         struct mdc_getattr_args  *ga = args;
1195         struct obd_export        *exp = ga->ga_exp;
1196         struct md_enqueue_info   *minfo = ga->ga_minfo;
1197         struct ldlm_enqueue_info *einfo = ga->ga_einfo;
1198         struct lookup_intent     *it;
1199         struct lustre_handle     *lockh;
1200         struct obd_device        *obddev;
1201         struct ldlm_reply        *lockrep;
1202         __u64                     flags = LDLM_FL_HAS_INTENT;
1203         ENTRY;
1204
1205         it    = &minfo->mi_it;
1206         lockh = &minfo->mi_lockh;
1207
1208         obddev = class_exp2obd(exp);
1209
1210         obd_put_request_slot(&obddev->u.cli);
1211         if (OBD_FAIL_CHECK(OBD_FAIL_MDC_GETATTR_ENQUEUE))
1212                 rc = -ETIMEDOUT;
1213
1214         rc = ldlm_cli_enqueue_fini(exp, req, einfo->ei_type, 1, einfo->ei_mode,
1215                                    &flags, NULL, 0, lockh, rc);
1216         if (rc < 0) {
1217                 CERROR("ldlm_cli_enqueue_fini: %d\n", rc);
1218                 mdc_clear_replay_flag(req, rc);
1219                 GOTO(out, rc);
1220         }
1221
1222         lockrep = req_capsule_server_get(&req->rq_pill, &RMF_DLM_REP);
1223         LASSERT(lockrep != NULL);
1224
1225         lockrep->lock_policy_res2 =
1226                 ptlrpc_status_ntoh(lockrep->lock_policy_res2);
1227
1228         rc = mdc_finish_enqueue(exp, req, einfo, it, lockh, rc);
1229         if (rc)
1230                 GOTO(out, rc);
1231
1232         rc = mdc_finish_intent_lock(exp, req, &minfo->mi_data, it, lockh);
1233         EXIT;
1234
1235 out:
1236         OBD_FREE_PTR(einfo);
1237         minfo->mi_cb(req, minfo, rc);
1238         return 0;
1239 }
1240
1241 int mdc_intent_getattr_async(struct obd_export *exp,
1242                              struct md_enqueue_info *minfo,
1243                              struct ldlm_enqueue_info *einfo)
1244 {
1245         struct md_op_data       *op_data = &minfo->mi_data;
1246         struct lookup_intent    *it = &minfo->mi_it;
1247         struct ptlrpc_request   *req;
1248         struct mdc_getattr_args *ga;
1249         struct obd_device       *obddev = class_exp2obd(exp);
1250         struct ldlm_res_id       res_id;
1251         /*XXX: Both MDS_INODELOCK_LOOKUP and MDS_INODELOCK_UPDATE are needed
1252          *     for statahead currently. Consider CMD in future, such two bits
1253          *     maybe managed by different MDS, should be adjusted then. */
1254         ldlm_policy_data_t       policy = {
1255                                         .l_inodebits = { MDS_INODELOCK_LOOKUP |
1256                                                          MDS_INODELOCK_UPDATE }
1257                                  };
1258         int                      rc = 0;
1259         __u64                    flags = LDLM_FL_HAS_INTENT;
1260         ENTRY;
1261
1262         CDEBUG(D_DLMTRACE, "name: %.*s in inode "DFID", intent: %s flags %#"
1263                 LPF64"o\n",
1264                 op_data->op_namelen, op_data->op_name, PFID(&op_data->op_fid1),
1265                 ldlm_it2str(it->it_op), it->it_flags);
1266
1267         fid_build_reg_res_name(&op_data->op_fid1, &res_id);
1268         req = mdc_intent_getattr_pack(exp, it, op_data);
1269         if (IS_ERR(req))
1270                 RETURN(PTR_ERR(req));
1271
1272         rc = obd_get_request_slot(&obddev->u.cli);
1273         if (rc != 0) {
1274                 ptlrpc_req_finished(req);
1275                 RETURN(rc);
1276         }
1277
1278         rc = ldlm_cli_enqueue(exp, &req, einfo, &res_id, &policy, &flags, NULL,
1279                               0, LVB_T_NONE, &minfo->mi_lockh, 1);
1280         if (rc < 0) {
1281                 obd_put_request_slot(&obddev->u.cli);
1282                 ptlrpc_req_finished(req);
1283                 RETURN(rc);
1284         }
1285
1286         CLASSERT(sizeof(*ga) <= sizeof(req->rq_async_args));
1287         ga = ptlrpc_req_async_args(req);
1288         ga->ga_exp = exp;
1289         ga->ga_minfo = minfo;
1290         ga->ga_einfo = einfo;
1291
1292         req->rq_interpret_reply = mdc_intent_getattr_async_interpret;
1293         ptlrpcd_add_req(req, PDL_POLICY_LOCAL, -1);
1294
1295         RETURN(0);
1296 }