lustre/ptlrpc/batch.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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2020, 2022, DDN/Whamcloud Storage Corporation.
  24  */
  25 /*
  26  * This file is part of Lustre, http://www.lustre.org/
  27  */
  28 /*
  29  * lustre/ptlrpc/batch.c
  30  *
  31  * Batch Metadata Updating on the client
  32  *
  33  * Author: Qian Yingjin <qian@ddn.com>
  34  */
  35
  36 #define DEBUG_SUBSYSTEM S_MDC
  37
  38 #include <linux/module.h>
  39 #include <obd_class.h>
  40 #include <obd.h>
  41 #ifdef HAVE_SERVER_SUPPORT
  42 #include <lustre_update.h>
  43 #else
  44
  45 #define OUT_UPDATE_REPLY_SIZE           4096
  46
  47 static inline struct lustre_msg *
  48 batch_update_reqmsg_next(struct batch_update_request *bur,
  49                          struct lustre_msg *reqmsg)
  50 {
  51         if (reqmsg)
  52                 return (struct lustre_msg *)((char *)reqmsg +
  53                                              lustre_packed_msg_size(reqmsg));
  54         else
  55                 return &bur->burq_reqmsg[0];
  56 }
  57
  58 static inline struct lustre_msg *
  59 batch_update_repmsg_next(struct batch_update_reply *bur,
  60                          struct lustre_msg *repmsg)
  61 {
  62         if (repmsg)
  63                 return (struct lustre_msg *)((char *)repmsg +
  64                                              lustre_packed_msg_size(repmsg));
  65         else
  66                 return &bur->burp_repmsg[0];
  67 }
  68 #endif
  69
  70 struct batch_update_buffer {
  71         struct batch_update_request     *bub_req;
  72         size_t                           bub_size;
  73         size_t                           bub_end;
  74         struct list_head                 bub_item;
  75 };
  76
  77 struct batch_update_args {
  78         struct batch_update_head        *ba_head;
  79 };
  80
  81 struct batch_work_resend {
  82         struct work_struct               bwr_work;
  83         struct batch_update_head        *bwr_head;
  84         int                              bwr_index;
  85 };
  86
  87 /**
  88  * Prepare inline update request
  89  *
  90  * Prepare BUT update ptlrpc inline request, and the request usuanlly includes
  91  * one update buffer, which does not need bulk transfer.
  92  */
  93 static int batch_prep_inline_update_req(struct batch_update_head *head,
  94                                         struct ptlrpc_request *req,
  95                                         int repsize)
  96 {
  97         struct batch_update_buffer *buf;
  98         struct but_update_header *buh;
  99         int rc;
 100
 101         buf = list_entry(head->buh_buf_list.next,
 102                           struct batch_update_buffer, bub_item);
 103         req_capsule_set_size(&req->rq_pill, &RMF_BUT_HEADER, RCL_CLIENT,
 104                              buf->bub_end + sizeof(*buh));
 105
 106         rc = ptlrpc_request_pack(req, LUSTRE_MDS_VERSION, MDS_BATCH);
 107         if (rc != 0)
 108                 RETURN(rc);
 109
 110         buh = req_capsule_client_get(&req->rq_pill, &RMF_BUT_HEADER);
 111         buh->buh_magic = BUT_HEADER_MAGIC;
 112         buh->buh_count = 1;
 113         buh->buh_inline_length = buf->bub_end;
 114         buh->buh_reply_size = repsize;
 115         buh->buh_update_count = head->buh_update_count;
 116
 117         memcpy(buh->buh_inline_data, buf->bub_req, buf->bub_end);
 118
 119         req_capsule_set_size(&req->rq_pill, &RMF_BUT_REPLY,
 120                              RCL_SERVER, repsize);
 121
 122         ptlrpc_request_set_replen(req);
 123         req->rq_request_portal = OUT_PORTAL;
 124         req->rq_reply_portal = OSC_REPLY_PORTAL;
 125
 126         RETURN(rc);
 127 }
 128
 129 static int batch_prep_update_req(struct batch_update_head *head,
 130                                  struct ptlrpc_request **reqp)
 131 {
 132         struct ptlrpc_request *req;
 133         struct ptlrpc_bulk_desc *desc;
 134         struct batch_update_buffer *buf;
 135         struct but_update_header *buh;
 136         struct but_update_buffer *bub;
 137         int repsize = head->buh_repsize;
 138         int page_count = 0;
 139         int total = 0;
 140         int rc;
 141
 142         ENTRY;
 143         repsize += round_up(offsetof(struct batch_update_reply, burp_repmsg[0]), 8);
 144         if (repsize < OUT_UPDATE_REPLY_SIZE)
 145                 repsize = OUT_UPDATE_REPLY_SIZE;
 146
 147         LASSERT(head->buh_buf_count > 0);
 148
 149         req = ptlrpc_request_alloc(class_exp2cliimp(head->buh_exp),
 150                                    &RQF_MDS_BATCH);
 151         if (req == NULL)
 152                 RETURN(-ENOMEM);
 153
 154         if (head->buh_buf_count == 1) {
 155                 buf = list_entry(head->buh_buf_list.next,
 156                                  struct batch_update_buffer, bub_item);
 157
 158                 /* Check whether it can be packed inline */
 159                 if (buf->bub_end + sizeof(struct but_update_header) <
 160                     OUT_UPDATE_MAX_INLINE_SIZE) {
 161                         rc = batch_prep_inline_update_req(head, req, repsize);
 162                         if (rc == 0)
 163                                 *reqp = req;
 164                         GOTO(out_req, rc);
 165                 }
 166         }
 167
 168         req_capsule_set_size(&req->rq_pill, &RMF_BUT_HEADER, RCL_CLIENT,
 169                              sizeof(struct but_update_header));
 170         req_capsule_set_size(&req->rq_pill, &RMF_BUT_BUF, RCL_CLIENT,
 171                              head->buh_buf_count * sizeof(*bub));
 172
 173         rc = ptlrpc_request_pack(req, LUSTRE_MDS_VERSION, MDS_BATCH);
 174         if (rc != 0)
 175                 GOTO(out_req, rc);
 176
 177         buh = req_capsule_client_get(&req->rq_pill, &RMF_BUT_HEADER);
 178         buh->buh_magic = BUT_HEADER_MAGIC;
 179         buh->buh_count = head->buh_buf_count;
 180         buh->buh_inline_length = 0;
 181         buh->buh_reply_size = repsize;
 182         buh->buh_update_count = head->buh_update_count;
 183         bub = req_capsule_client_get(&req->rq_pill, &RMF_BUT_BUF);
 184         list_for_each_entry(buf, &head->buh_buf_list, bub_item) {
 185                 bub->bub_size = buf->bub_size;
 186                 bub++;
 187                 /* First *and* last might be partial pages, hence +1 */
 188                 page_count += DIV_ROUND_UP(buf->bub_size, PAGE_SIZE) + 1;
 189         }
 190
 191         req->rq_bulk_write = 1;
 192         desc = ptlrpc_prep_bulk_imp(req, page_count,
 193                                     MD_MAX_BRW_SIZE >> LNET_MTU_BITS,
 194                                     PTLRPC_BULK_GET_SOURCE,
 195                                     MDS_BULK_PORTAL,
 196                                     &ptlrpc_bulk_kiov_nopin_ops);
 197         if (desc == NULL)
 198                 GOTO(out_req, rc = -ENOMEM);
 199
 200         list_for_each_entry(buf, &head->buh_buf_list, bub_item) {
 201                 desc->bd_frag_ops->add_iov_frag(desc, buf->bub_req,
 202                                                 buf->bub_size);
 203                 total += buf->bub_size;
 204         }
 205         CDEBUG(D_OTHER, "Total %d in %u\n", total, head->buh_update_count);
 206
 207         req_capsule_set_size(&req->rq_pill, &RMF_BUT_REPLY,
 208                              RCL_SERVER, repsize);
 209
 210         ptlrpc_request_set_replen(req);
 211         req->rq_request_portal = OUT_PORTAL;
 212         req->rq_reply_portal = OSC_REPLY_PORTAL;
 213         *reqp = req;
 214
 215 out_req:
 216         if (rc < 0)
 217                 ptlrpc_req_put(req);
 218
 219         RETURN(rc);
 220 }
 221
 222 static struct batch_update_buffer *
 223 current_batch_update_buffer(struct batch_update_head *head)
 224 {
 225         if (list_empty(&head->buh_buf_list))
 226                 return NULL;
 227
 228         return list_entry(head->buh_buf_list.prev, struct batch_update_buffer,
 229                           bub_item);
 230 }
 231
 232 static int batch_update_buffer_create(struct batch_update_head *head,
 233                                       size_t size)
 234 {
 235         struct batch_update_buffer *buf;
 236         struct batch_update_request *bur;
 237
 238         OBD_ALLOC_PTR(buf);
 239         if (buf == NULL)
 240                 return -ENOMEM;
 241
 242         LASSERT(size > 0);
 243         size = round_up(size, PAGE_SIZE);
 244         OBD_ALLOC_LARGE(bur, size);
 245         if (bur == NULL) {
 246                 OBD_FREE_PTR(buf);
 247                 return -ENOMEM;
 248         }
 249
 250         bur->burq_magic = BUT_REQUEST_MAGIC;
 251         bur->burq_count = 0;
 252         buf->bub_req = bur;
 253         buf->bub_size = size;
 254         buf->bub_end = sizeof(*bur);
 255         INIT_LIST_HEAD(&buf->bub_item);
 256         list_add_tail(&buf->bub_item, &head->buh_buf_list);
 257         head->buh_buf_count++;
 258
 259         return 0;
 260 }
 261
 262 /**
 263  * Destroy an @object_update_callback.
 264  */
 265 static void object_update_callback_fini(struct object_update_callback *ouc)
 266 {
 267         LASSERT(list_empty(&ouc->ouc_item));
 268
 269         OBD_FREE_PTR(ouc);
 270 }
 271
 272 /**
 273  * Insert an @object_update_callback into the the @batch_update_head.
 274  *
 275  * Usually each update in @batch_update_head will have one correspondent
 276  * callback, and these callbacks will be called in ->rq_interpret_reply.
 277  */
 278 static int
 279 batch_insert_update_callback(struct batch_update_head *head, void *data,
 280                              object_update_interpret_t interpret)
 281 {
 282         struct object_update_callback *ouc;
 283
 284         OBD_ALLOC_PTR(ouc);
 285         if (ouc == NULL)
 286                 return -ENOMEM;
 287
 288         INIT_LIST_HEAD(&ouc->ouc_item);
 289         ouc->ouc_interpret = interpret;
 290         ouc->ouc_head = head;
 291         ouc->ouc_data = data;
 292         list_add_tail(&ouc->ouc_item, &head->buh_cb_list);
 293
 294         return 0;
 295 }
 296
 297 /**
 298  * Allocate and initialize batch update request.
 299  *
 300  * @batch_update_head is being used to track updates being executed on
 301  * this OBD device. The update buffer will be 4K initially, and increased
 302  * if needed.
 303  */
 304 static struct batch_update_head *
 305 batch_update_request_create(struct obd_export *exp, struct lu_batch *bh)
 306 {
 307         struct batch_update_head *head;
 308         int rc;
 309
 310         OBD_ALLOC_PTR(head);
 311         if (head == NULL)
 312                 return ERR_PTR(-ENOMEM);
 313
 314         INIT_LIST_HEAD(&head->buh_cb_list);
 315         INIT_LIST_HEAD(&head->buh_buf_list);
 316         head->buh_exp = exp;
 317         head->buh_batch = bh;
 318
 319         rc = batch_update_buffer_create(head, PAGE_SIZE);
 320         if (rc != 0) {
 321                 OBD_FREE_PTR(head);
 322                 RETURN(ERR_PTR(rc));
 323         }
 324
 325         return head;
 326 }
 327
 328 static void batch_update_request_destroy(struct batch_update_head *head)
 329 {
 330         struct batch_update_buffer *bub, *tmp;
 331
 332         if (head == NULL)
 333                 return;
 334
 335         list_for_each_entry_safe(bub, tmp, &head->buh_buf_list, bub_item) {
 336                 list_del(&bub->bub_item);
 337                 if (bub->bub_req)
 338                         OBD_FREE_LARGE(bub->bub_req, bub->bub_size);
 339                 OBD_FREE_PTR(bub);
 340         }
 341
 342         OBD_FREE_PTR(head);
 343 }
 344
 345 static void cli_batch_resend_work(struct work_struct *data);
 346
 347 static int batch_update_request_fini(struct batch_update_head *head,
 348                                      struct ptlrpc_request *req,
 349                                      struct batch_update_reply *reply, int rc)
 350 {
 351         struct object_update_callback *ouc, *next;
 352         struct lustre_msg *repmsg = NULL;
 353         int count = 0;
 354         int index = 0;
 355
 356         ENTRY;
 357
 358         if (reply)
 359                 count = reply->burp_count;
 360
 361         list_for_each_entry_safe(ouc, next, &head->buh_cb_list, ouc_item) {
 362                 int rc1 = 0;
 363
 364                 /*
 365                  * The peer may only have handled some requests (indicated by
 366                  * @count) in the packaged OUT PRC, we can only get results
 367                  * for the handled part.
 368                  */
 369                 if (index < count) {
 370                         repmsg = batch_update_repmsg_next(reply, repmsg);
 371                         if (repmsg == NULL)
 372                                 rc1 = -EPROTO;
 373                         else
 374                                 rc1 = repmsg->lm_result;
 375                 } else {
 376                         /*
 377                          * The peer did not handle these request, let us return
 378                          * -ECANCELED to the update interpreter for now.
 379                          */
 380                         repmsg = NULL;
 381                         rc1 = -ECANCELED;
 382                         /*
 383                          * TODO: resend the unfinished sub request when the
 384                          * return code is -EOVERFLOW.
 385                          */
 386                         if (rc == -EOVERFLOW) {
 387                                 struct batch_work_resend *work;
 388
 389                                 OBD_ALLOC_GFP(work, sizeof(*work), GFP_ATOMIC);
 390                                 if (work == NULL) {
 391                                         rc1 = -ENOMEM;
 392                                 } else {
 393                                         INIT_WORK(&work->bwr_work,
 394                                                   cli_batch_resend_work);
 395                                         work->bwr_head = head;
 396                                         work->bwr_index = index;
 397                                         schedule_work(&work->bwr_work);
 398                                         RETURN(0);
 399                                 }
 400                         }
 401                 }
 402
 403                 list_del_init(&ouc->ouc_item);
 404                 if (ouc->ouc_interpret != NULL)
 405                         ouc->ouc_interpret(req, repmsg, ouc, rc1);
 406
 407                 index++;
 408                 object_update_callback_fini(ouc);
 409                 if (rc == 0 && rc1 < 0)
 410                         rc = rc1;
 411         }
 412
 413         batch_update_request_destroy(head);
 414
 415         RETURN(rc);
 416 }
 417
 418 static int batch_update_interpret(const struct lu_env *env,
 419                                   struct ptlrpc_request *req,
 420                                   void *args, int rc)
 421 {
 422         struct batch_update_args *aa = (struct batch_update_args *)args;
 423         struct batch_update_reply *reply = NULL;
 424
 425         ENTRY;
 426
 427         if (aa->ba_head == NULL)
 428                 RETURN(0);
 429
 430         ptlrpc_put_mod_rpc_slot(req);
 431         /* Unpack the results from the reply message. */
 432         if (req->rq_repmsg != NULL && req->rq_replied) {
 433                 reply = req_capsule_server_sized_get(&req->rq_pill,
 434                                                      &RMF_BUT_REPLY,
 435                                                      sizeof(*reply));
 436                 if ((reply == NULL ||
 437                      reply->burp_magic != BUT_REPLY_MAGIC) && rc == 0)
 438                         rc = -EPROTO;
 439         }
 440
 441         rc = batch_update_request_fini(aa->ba_head, req, reply, rc);
 442
 443         RETURN(rc);
 444 }
 445
 446 static int batch_send_update_req(const struct lu_env *env,
 447                                  struct batch_update_head *head)
 448 {
 449         struct obd_device *obd;
 450         struct ptlrpc_request *req = NULL;
 451         struct batch_update_args *aa;
 452         struct lu_batch *bh;
 453         __u32 flags = 0;
 454         int rc;
 455
 456         ENTRY;
 457
 458         if (head == NULL)
 459                 RETURN(0);
 460
 461         obd = class_exp2obd(head->buh_exp);
 462         bh = head->buh_batch;
 463         if (bh)
 464                 flags = bh->lbt_flags;
 465
 466         rc = batch_prep_update_req(head, &req);
 467         if (rc) {
 468                 rc = batch_update_request_fini(head, NULL, NULL, rc);
 469                 RETURN(rc);
 470         }
 471
 472         aa = ptlrpc_req_async_args(aa, req);
 473         aa->ba_head = head;
 474         req->rq_interpret_reply = batch_update_interpret;
 475
 476         /*
 477          * Only acquire modification RPC slot for the batched RPC
 478          * which contains metadata updates.
 479          */
 480         if (!(flags & BATCH_FL_RDONLY))
 481                 ptlrpc_get_mod_rpc_slot(req);
 482
 483         if (flags & BATCH_FL_SYNC) {
 484                 rc = ptlrpc_queue_wait(req);
 485         } else {
 486                 if (bh && (flags & BATCH_FL_RQSET)) {
 487                         ptlrpc_set_add_req(bh->lbt_rqset, req);
 488                         ptlrpc_check_set(env, bh->lbt_rqset);
 489                 } else {
 490                         ptlrpcd_add_req(req);
 491                 }
 492                 req = NULL;
 493         }
 494
 495         if (req != NULL)
 496                 ptlrpc_req_put(req);
 497
 498         lprocfs_oh_tally_log2(&obd->u.cli.cl_batch_rpc_hist,
 499                               head->buh_update_count);
 500         RETURN(rc);
 501 }
 502
 503 static int batch_update_request_add(struct batch_update_head **headp,
 504                                     struct md_op_item *item,
 505                                     md_update_pack_t packer,
 506                                     object_update_interpret_t interpreter)
 507 {
 508         struct batch_update_head *head = *headp;
 509         struct lu_batch *bh = head->buh_batch;
 510         struct batch_update_buffer *buf;
 511         struct lustre_msg *reqmsg;
 512         size_t max_len;
 513         int rc;
 514
 515         ENTRY;
 516
 517         for (; ;) {
 518                 buf = current_batch_update_buffer(head);
 519                 LASSERT(buf != NULL);
 520                 max_len = buf->bub_size - buf->bub_end;
 521                 reqmsg = (struct lustre_msg *)((char *)buf->bub_req +
 522                                                 buf->bub_end);
 523                 rc = packer(head, reqmsg, &max_len, item);
 524                 if (rc == -E2BIG) {
 525                         int rc2;
 526
 527                         /* Create new batch object update buffer */
 528                         rc2 = batch_update_buffer_create(head,
 529                                 max_len + offsetof(struct batch_update_request,
 530                                                    burq_reqmsg[0]) + 1);
 531                         if (rc2 != 0) {
 532                                 rc = rc2;
 533                                 break;
 534                         }
 535                 } else {
 536                         if (rc == 0) {
 537                                 buf->bub_end += max_len;
 538                                 buf->bub_req->burq_count++;
 539                                 head->buh_update_count++;
 540                                 head->buh_repsize += reqmsg->lm_repsize;
 541                         }
 542                         break;
 543                 }
 544         }
 545
 546         if (rc)
 547                 GOTO(out, rc);
 548
 549         rc = batch_insert_update_callback(head, item, interpreter);
 550         if (rc)
 551                 GOTO(out, rc);
 552
 553         /* Unplug the batch queue if accumulated enough update requests. */
 554         if (bh->lbt_max_count && head->buh_update_count >= bh->lbt_max_count) {
 555                 rc = batch_send_update_req(NULL, head);
 556                 *headp = NULL;
 557         }
 558 out:
 559         if (rc) {
 560                 batch_update_request_destroy(head);
 561                 *headp = NULL;
 562         }
 563
 564         RETURN(rc);
 565 }
 566
 567 static void cli_batch_resend_work(struct work_struct *data)
 568 {
 569         struct batch_work_resend *work = container_of(data,
 570                                         struct batch_work_resend, bwr_work);
 571         struct batch_update_head *obuh = work->bwr_head;
 572         struct object_update_callback *ouc;
 573         struct batch_update_head *head;
 574         struct batch_update_buffer *buf;
 575         struct batch_update_buffer *tmp;
 576         int index = work->bwr_index;
 577         int rc = 0;
 578         int i = 0;
 579
 580         ENTRY;
 581
 582         head = batch_update_request_create(obuh->buh_exp, NULL);
 583         if (head == NULL)
 584                 GOTO(err_up, rc = -ENOMEM);
 585
 586         list_for_each_entry_safe(buf, tmp, &obuh->buh_buf_list, bub_item) {
 587                 struct batch_update_request *bur = buf->bub_req;
 588                 struct batch_update_buffer *newbuf;
 589                 struct lustre_msg *reqmsg = NULL;
 590                 size_t max_len;
 591                 int j;
 592
 593                 if (i + bur->burq_count < index) {
 594                         i += bur->burq_count;
 595                         continue;
 596                 }
 597
 598                 /* reused the allocated buffer */
 599                 if (i >= index) {
 600                         list_move_tail(&buf->bub_item, &head->buh_buf_list);
 601                         head->buh_update_count += buf->bub_req->burq_count;
 602                         head->buh_buf_count++;
 603                         continue;
 604                 }
 605
 606                 for (j = 0; j < bur->burq_count; j++) {
 607                         struct lustre_msg *newmsg;
 608                         __u32 msgsz;
 609
 610                         reqmsg = batch_update_reqmsg_next(bur, reqmsg);
 611                         if (i + j < index)
 612                                 continue;
 613 repeat:
 614                         newbuf = current_batch_update_buffer(head);
 615                         LASSERT(newbuf != NULL);
 616                         max_len = newbuf->bub_size - newbuf->bub_end;
 617                         newmsg = (struct lustre_msg *)((char *)newbuf->bub_req +
 618                                                        newbuf->bub_end);
 619                         msgsz = lustre_packed_msg_size(reqmsg);
 620                         if (msgsz >= max_len) {
 621                                 int rc2;
 622
 623                                 /* Create new batch update buffer */
 624                                 rc2 = batch_update_buffer_create(head, msgsz +
 625                                         offsetof(struct batch_update_request,
 626                                                  burq_reqmsg[0]) + 1);
 627                                 if (rc2 != 0)
 628                                         GOTO(err_up, rc = rc2);
 629                                 GOTO(repeat, rc);
 630                         }
 631
 632                         memcpy(newmsg, reqmsg, msgsz);
 633                         newbuf->bub_end += msgsz;
 634                         newbuf->bub_req->burq_count++;
 635                         head->buh_update_count++;
 636                 }
 637
 638                 i = index;
 639         }
 640
 641         list_splice_init(&obuh->buh_cb_list, &head->buh_cb_list);
 642         list_for_each_entry(ouc, &head->buh_cb_list, ouc_item)
 643                 ouc->ouc_head = head;
 644
 645         head->buh_repsize = BUT_MAXREPSIZE - SPTLRPC_MAX_PAYLOAD;
 646         rc = batch_send_update_req(NULL, head);
 647         if (rc)
 648                 GOTO(err_up, rc);
 649
 650         batch_update_request_destroy(obuh);
 651         OBD_FREE_PTR(work);
 652         RETURN_EXIT;
 653
 654 err_up:
 655         batch_update_request_fini(obuh, NULL, NULL, rc);
 656         if (head != NULL)
 657                 batch_update_request_fini(head, NULL, NULL, rc);
 658
 659         OBD_FREE_PTR(work);
 660         RETURN_EXIT;
 661 }
 662
 663 struct lu_batch *cli_batch_create(struct obd_export *exp,
 664                                   enum lu_batch_flags flags, __u32 max_count)
 665 {
 666         struct cli_batch *cbh;
 667         struct lu_batch *bh;
 668
 669         ENTRY;
 670
 671         OBD_ALLOC_PTR(cbh);
 672         if (!cbh)
 673                 RETURN(ERR_PTR(-ENOMEM));
 674
 675         bh = &cbh->cbh_super;
 676         bh->lbt_result = 0;
 677         bh->lbt_flags = flags;
 678         bh->lbt_max_count = max_count;
 679
 680         cbh->cbh_head = batch_update_request_create(exp, bh);
 681         if (IS_ERR(cbh->cbh_head)) {
 682                 bh = (struct lu_batch *)cbh->cbh_head;
 683                 OBD_FREE_PTR(cbh);
 684         }
 685
 686         RETURN(bh);
 687 }
 688 EXPORT_SYMBOL(cli_batch_create);
 689
 690 int cli_batch_stop(struct obd_export *exp, struct lu_batch *bh)
 691 {
 692         struct cli_batch *cbh;
 693         int rc;
 694
 695         ENTRY;
 696
 697         cbh = container_of(bh, struct cli_batch, cbh_super);
 698         rc = batch_send_update_req(NULL, cbh->cbh_head);
 699
 700         OBD_FREE_PTR(cbh);
 701         RETURN(rc);
 702 }
 703 EXPORT_SYMBOL(cli_batch_stop);
 704
 705 int cli_batch_flush(struct obd_export *exp, struct lu_batch *bh, bool wait)
 706 {
 707         struct cli_batch *cbh;
 708         int rc;
 709
 710         ENTRY;
 711
 712         cbh = container_of(bh, struct cli_batch, cbh_super);
 713         if (cbh->cbh_head == NULL)
 714                 RETURN(0);
 715
 716         rc = batch_send_update_req(NULL, cbh->cbh_head);
 717         cbh->cbh_head = NULL;
 718
 719         RETURN(rc);
 720 }
 721 EXPORT_SYMBOL(cli_batch_flush);
 722
 723 int cli_batch_add(struct obd_export *exp, struct lu_batch *bh,
 724                   struct md_op_item *item, md_update_pack_t packer,
 725                   object_update_interpret_t interpreter)
 726 {
 727         struct cli_batch *cbh;
 728         int rc;
 729
 730         ENTRY;
 731
 732         cbh = container_of(bh, struct cli_batch, cbh_super);
 733         if (cbh->cbh_head == NULL) {
 734                 cbh->cbh_head = batch_update_request_create(exp, bh);
 735                 if (IS_ERR(cbh->cbh_head))
 736                         RETURN(PTR_ERR(cbh->cbh_head));
 737         }
 738
 739         rc = batch_update_request_add(&cbh->cbh_head, item,
 740                                       packer, interpreter);
 741
 742         RETURN(rc);
 743 }
 744 EXPORT_SYMBOL(cli_batch_add);