lustre/lov/lov_pack.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/lov/lov_pack.c
  37  *
  38  * (Un)packing of OST/MDS requests
  39  *
  40  * Author: Andreas Dilger <adilger@clusterfs.com>
  41  */
  42
  43 #define DEBUG_SUBSYSTEM S_LOV
  44 #ifndef __KERNEL__
  45 #include <liblustre.h>
  46 #endif
  47
  48 #include <lustre_net.h>
  49 #include <obd.h>
  50 #include <obd_lov.h>
  51 #include <obd_class.h>
  52 #include <obd_support.h>
  53 #include <lustre/lustre_user.h>
  54
  55 #include "lov_internal.h"
  56
  57 static void lov_dump_lmm_common(int level, void *lmmp)
  58 {
  59         struct lov_mds_md *lmm = lmmp;
  60
  61         CDEBUG(level, "objid "LPX64", magic 0x%08x, pattern %#x\n",
  62                (__u64)le64_to_cpu(lmm->lmm_object_id),
  63                le32_to_cpu(lmm->lmm_magic),
  64                le32_to_cpu(lmm->lmm_pattern));
  65         CDEBUG(level,"stripe_size %u, stripe_count %u\n",
  66                le32_to_cpu(lmm->lmm_stripe_size),
  67                le32_to_cpu(lmm->lmm_stripe_count));
  68 }
  69
  70 static void lov_dump_lmm_objects(int level, struct lov_ost_data *lod,
  71                                  int stripe_count)
  72 {
  73         int i;
  74
  75         if (stripe_count > LOV_V1_INSANE_STRIPE_COUNT) {
  76                 CDEBUG(level, "bad stripe_count %u > max_stripe_count %u\n",
  77                        stripe_count, LOV_V1_INSANE_STRIPE_COUNT);
  78         }
  79
  80         for (i = 0; i < stripe_count; ++i, ++lod) {
  81                 CDEBUG(level, "stripe %u idx %u subobj "LPX64"/"LPX64"\n", i,
  82                        le32_to_cpu(lod->l_ost_idx),
  83                        (__u64)le64_to_cpu(lod->l_object_gr),
  84                        (__u64)le64_to_cpu(lod->l_object_id));
  85         }
  86 }
  87
  88 void lov_dump_lmm_v1(int level, struct lov_mds_md_v1 *lmm)
  89 {
  90         lov_dump_lmm_common(level, lmm);
  91         lov_dump_lmm_objects(level, lmm->lmm_objects,
  92                              le32_to_cpu(lmm->lmm_stripe_count));
  93 }
  94
  95 void lov_dump_lmm_join(int level, struct lov_mds_md_join *lmmj)
  96 {
  97         lov_dump_lmm_common(level, &lmmj->lmmj_md);
  98         CDEBUG(level, "extent_count %u\n",
  99                le32_to_cpu(lmmj->lmmj_extent_count));
 100 }
 101
 102 void lov_dump_lmm_v3(int level, struct lov_mds_md_v3 *lmm)
 103 {
 104         lov_dump_lmm_common(level, lmm);
 105         CDEBUG(level,"pool_name "LOV_POOLNAMEF"\n", lmm->lmm_pool_name);
 106         lov_dump_lmm_objects(level, lmm->lmm_objects,
 107                              le32_to_cpu(lmm->lmm_stripe_count));
 108 }
 109
 110 void lov_dump_lmm(int level, void *lmm)
 111 {
 112         int magic;
 113
 114         magic = ((struct lov_mds_md_v1 *)(lmm))->lmm_magic;
 115         switch (magic) {
 116         case LOV_MAGIC_V1:
 117                 return lov_dump_lmm_v1(level, (struct lov_mds_md_v1 *)(lmm));
 118         case LOV_MAGIC_JOIN:
 119                 return lov_dump_lmm_join(level, (struct lov_mds_md_join *)(lmm));
 120         case LOV_MAGIC_V3:
 121                 return lov_dump_lmm_v3(level, (struct lov_mds_md_v3 *)(lmm));
 122         default:
 123                 CERROR("Cannot recognize lmm_magic %x", magic);
 124         }
 125         return;
 126 }
 127
 128 #define LMM_ASSERT(test)                                                \
 129 do {                                                                    \
 130         if (!(test)) lov_dump_lmm(D_ERROR, lmm);                        \
 131         LASSERT(test); /* so we know what assertion failed */           \
 132 } while(0)
 133
 134 /* Pack LOV object metadata for disk storage.  It is packed in LE byte
 135  * order and is opaque to the networking layer.
 136  *
 137  * XXX In the future, this will be enhanced to get the EA size from the
 138  *     underlying OSC device(s) to get their EA sizes so we can stack
 139  *     LOVs properly.  For now lov_mds_md_size() just assumes one obd_id
 140  *     per stripe.
 141  */
 142 int lov_packmd(struct obd_export *exp, struct lov_mds_md **lmmp,
 143                struct lov_stripe_md *lsm)
 144 {
 145         struct obd_device *obd = class_exp2obd(exp);
 146         struct lov_obd *lov = &obd->u.lov;
 147         struct lov_mds_md_v1 *lmmv1;
 148         struct lov_mds_md_v3 *lmmv3;
 149         struct lov_oinfo *loi;
 150         int stripe_count;
 151         struct lov_ost_data_v1 *lmm_objects;
 152         int lmm_size, lmm_magic;
 153         int i;
 154         ENTRY;
 155
 156         if (lsm) {
 157                 lmm_magic = lsm->lsm_magic;
 158
 159                 if (!lmmp) {
 160                         stripe_count = lov_get_stripecnt(lov,
 161                                                          lsm->lsm_stripe_count);
 162                         lsm->lsm_stripe_count = stripe_count;
 163                 } else {
 164                         stripe_count = lsm->lsm_stripe_count;
 165                 }
 166         } else {
 167                 /* No needs to allocated more than LOV_MAX_STRIPE_COUNT.
 168                  * Anyway, this is pretty inaccurate since ld_tgt_count now
 169                  * represents max index and we should rely on the actual number
 170                  * of OSTs instead */
 171                 stripe_count = min((__u32)LOV_MAX_STRIPE_COUNT,
 172                                    lov->desc.ld_tgt_count);
 173
 174                 if (lmmp && *lmmp)
 175                         lmm_magic = le32_to_cpu((*lmmp)->lmm_magic);
 176                 else
 177                         /* lsm == NULL and lmmp == NULL */
 178                         lmm_magic = LOV_MAGIC;
 179         }
 180
 181         if ((lmm_magic != LOV_MAGIC_V1) &&
 182             (lmm_magic != LOV_MAGIC_V3)) {
 183                 CERROR("bad mem LOV MAGIC: 0x%08X != 0x%08X nor 0x%08X\n",
 184                        lmm_magic, LOV_MAGIC_V1, LOV_MAGIC_V3);
 185                 RETURN(-EINVAL);
 186         }
 187
 188         /* XXX LOV STACKING call into osc for sizes */
 189         lmm_size = lov_mds_md_size(stripe_count, lmm_magic);
 190
 191         if (!lmmp)
 192                 RETURN(lmm_size);
 193
 194         if (*lmmp && !lsm) {
 195                 stripe_count = le32_to_cpu((*lmmp)->lmm_stripe_count);
 196                 lmm_size = lov_mds_md_size(stripe_count, le32_to_cpu((*lmmp)->lmm_magic));
 197                 OBD_FREE(*lmmp, lmm_size);
 198                 *lmmp = NULL;
 199                 RETURN(0);
 200         }
 201
 202         if (!*lmmp) {
 203                 OBD_ALLOC(*lmmp, lmm_size);
 204                 if (!*lmmp)
 205                         RETURN(-ENOMEM);
 206         }
 207
 208         CDEBUG(D_INFO, "lov_packmd: LOV_MAGIC 0x%08X, lmm_size = %d \n",
 209                lmm_magic, lmm_size);
 210
 211         lmmv1 = *lmmp;
 212         lmmv3 = (struct lov_mds_md_v3 *)*lmmp;
 213         if (lmm_magic == LOV_MAGIC_V3)
 214                 lmmv3->lmm_magic = cpu_to_le32(LOV_MAGIC_V3);
 215         else
 216                 lmmv1->lmm_magic = cpu_to_le32(LOV_MAGIC_V1);
 217
 218         if (!lsm)
 219                 RETURN(lmm_size);
 220
 221         /* lmmv1 and lmmv3 point to the same struct and have the
 222          * same first fields
 223          */
 224         lmmv1->lmm_pattern = cpu_to_le32(lsm->lsm_pattern);
 225         lmmv1->lmm_object_id = cpu_to_le64(lsm->lsm_object_id);
 226         lmmv1->lmm_object_gr = cpu_to_le64(lsm->lsm_object_gr);
 227         lmmv1->lmm_stripe_size = cpu_to_le32(lsm->lsm_stripe_size);
 228         lmmv1->lmm_stripe_count = cpu_to_le32(stripe_count);
 229         if (lsm->lsm_magic == LOV_MAGIC_V3) {
 230                 strncpy(lmmv3->lmm_pool_name, lsm->lsm_pool_name, LOV_MAXPOOLNAME);
 231                 lmm_objects = lmmv3->lmm_objects;
 232         } else {
 233                 lmm_objects = lmmv1->lmm_objects;
 234         }
 235
 236         for (i = 0; i < stripe_count; i++) {
 237                 loi = lsm->lsm_oinfo[i];
 238                 /* XXX LOV STACKING call down to osc_packmd() to do packing */
 239                 LASSERTF(loi->loi_id, "lmm_oid "LPU64" stripe %u/%u idx %u\n",
 240                          lmmv1->lmm_object_id, i, stripe_count, loi->loi_ost_idx);
 241                 lmm_objects[i].l_object_id = cpu_to_le64(loi->loi_id);
 242                 lmm_objects[i].l_object_gr = cpu_to_le64(loi->loi_gr);
 243                 lmm_objects[i].l_ost_gen = cpu_to_le32(loi->loi_ost_gen);
 244                 lmm_objects[i].l_ost_idx = cpu_to_le32(loi->loi_ost_idx);
 245         }
 246
 247         RETURN(lmm_size);
 248 }
 249
 250 /* Find the max stripecount we should use */
 251 int lov_get_stripecnt(struct lov_obd *lov, __u32 stripe_count)
 252 {
 253         if (!stripe_count)
 254                 stripe_count = lov->desc.ld_default_stripe_count;
 255         if (stripe_count > lov->desc.ld_active_tgt_count)
 256                 stripe_count = lov->desc.ld_active_tgt_count;
 257         if (!stripe_count)
 258                 stripe_count = 1;
 259         /* for now, we limit the stripe count directly, when bug 4424 is
 260          * fixed this needs to be somewhat dynamic based on whether ext3
 261          * can handle larger EA sizes. */
 262         if (stripe_count > LOV_MAX_STRIPE_COUNT)
 263                 stripe_count = LOV_MAX_STRIPE_COUNT;
 264
 265         return stripe_count;
 266 }
 267
 268
 269 static int lov_verify_lmm(void *lmm, int lmm_bytes, int *stripe_count)
 270 {
 271         int rc;
 272
 273         if (lsm_op_find(le32_to_cpu(*(__u32 *)lmm)) == NULL) {
 274                 char *buffer;
 275                 int sz;
 276
 277                 CERROR("bad disk LOV MAGIC: 0x%08X; dumping LMM (size=%d):\n",
 278                        le32_to_cpu(*(__u32 *)lmm), lmm_bytes);
 279                 sz = lmm_bytes * 2 + 1;
 280                 OBD_ALLOC(buffer, sz);
 281                 if (buffer != NULL) {
 282                         int i;
 283
 284                         for (i = 0; i < lmm_bytes; i++)
 285                                 sprintf(buffer+2*i, "%.2X", ((char *)lmm)[i]);
 286                         buffer[sz] = '\0';
 287                         CERROR("%s\n", buffer);
 288                         OBD_FREE(buffer, sz);
 289                 }
 290                 return -EINVAL;
 291         }
 292         rc = lsm_op_find(le32_to_cpu(*(__u32 *)lmm))->lsm_lmm_verify(lmm,
 293                                      lmm_bytes, stripe_count);
 294         return rc;
 295 }
 296
 297 int lov_alloc_memmd(struct lov_stripe_md **lsmp, int stripe_count,
 298                       int pattern, int magic)
 299 {
 300         int i, lsm_size;
 301         ENTRY;
 302
 303         CDEBUG(D_INFO, "alloc lsm, stripe_count %d\n", stripe_count);
 304
 305         *lsmp = lsm_alloc_plain(stripe_count, &lsm_size);
 306         if (!*lsmp) {
 307                 CERROR("can't allocate lsmp, stripe_count %d\n", stripe_count);
 308                 RETURN(-ENOMEM);
 309         }
 310
 311         spin_lock_init(&(*lsmp)->lsm_lock);
 312         (*lsmp)->lsm_magic = magic;
 313         (*lsmp)->lsm_stripe_count = stripe_count;
 314         (*lsmp)->lsm_maxbytes = LUSTRE_STRIPE_MAXBYTES * stripe_count;
 315         (*lsmp)->lsm_pattern = pattern;
 316         (*lsmp)->lsm_pool_name[0] = '\0';
 317         (*lsmp)->lsm_oinfo[0]->loi_ost_idx = ~0;
 318
 319         for (i = 0; i < stripe_count; i++)
 320                 loi_init((*lsmp)->lsm_oinfo[i]);
 321
 322         RETURN(lsm_size);
 323 }
 324
 325 void lov_free_memmd(struct lov_stripe_md **lsmp)
 326 {
 327         struct lov_stripe_md *lsm = *lsmp;
 328
 329         LASSERT(lsm_op_find(lsm->lsm_magic) != NULL);
 330         lsm_op_find(lsm->lsm_magic)->lsm_free(lsm);
 331
 332         *lsmp = NULL;
 333 }
 334
 335
 336 /* Unpack LOV object metadata from disk storage.  It is packed in LE byte
 337  * order and is opaque to the networking layer.
 338  */
 339 int lov_unpackmd(struct obd_export *exp,  struct lov_stripe_md **lsmp,
 340                  struct lov_mds_md *lmm, int lmm_bytes)
 341 {
 342         struct obd_device *obd = class_exp2obd(exp);
 343         struct lov_obd *lov = &obd->u.lov;
 344         int rc = 0, stripe_count, lsm_size;
 345         __u32 magic;
 346         ENTRY;
 347
 348         /* If passed an MDS struct use values from there, otherwise defaults */
 349         if (lmm) {
 350                 rc = lov_verify_lmm(lmm, lmm_bytes, &stripe_count);
 351                 if (rc)
 352                         RETURN(rc);
 353                 magic = le32_to_cpu(lmm->lmm_magic);
 354         } else {
 355                 stripe_count = lov_get_stripecnt(lov, 0);
 356                 magic = LOV_MAGIC;
 357         }
 358
 359         /* If we aren't passed an lsmp struct, we just want the size */
 360         if (!lsmp) {
 361                 /* XXX LOV STACKING call into osc for sizes */
 362                 LBUG();
 363                 RETURN(lov_stripe_md_size(stripe_count));
 364         }
 365
 366         /* If we are passed an allocated struct but nothing to unpack, free */
 367         if (*lsmp && !lmm) {
 368                 lov_free_memmd(lsmp);
 369                 RETURN(0);
 370         }
 371
 372         lsm_size = lov_alloc_memmd(lsmp, stripe_count, LOV_PATTERN_RAID0,
 373                                    magic);
 374         if (lsm_size < 0)
 375                 RETURN(lsm_size);
 376
 377         /* If we are passed a pointer but nothing to unpack, we only alloc */
 378         if (!lmm)
 379                 RETURN(lsm_size);
 380
 381         LASSERT(lsm_op_find(magic) != NULL);
 382         rc = lsm_op_find(magic)->lsm_unpackmd(lov, *lsmp, lmm);
 383         if (rc) {
 384                 lov_free_memmd(lsmp);
 385                 RETURN(rc);
 386         }
 387
 388         RETURN(lsm_size);
 389 }
 390
 391 /* Configure object striping information on a new file.
 392  *
 393  * @lmmu is a pointer to a user struct with one or more of the fields set to
 394  * indicate the application preference: lmm_stripe_count, lmm_stripe_size,
 395  * lmm_stripe_offset, and lmm_stripe_pattern.  lmm_magic must be LOV_MAGIC.
 396  * @lsmp is a pointer to an in-core stripe MD that needs to be filled in.
 397  */
 398 int lov_setstripe(struct obd_export *exp, struct lov_stripe_md **lsmp,
 399                   struct lov_user_md *lump)
 400 {
 401         struct obd_device *obd = class_exp2obd(exp);
 402         struct lov_obd *lov = &obd->u.lov;
 403         struct lov_user_md_v3 lumv3;
 404         struct lov_user_md_v1 *lumv1 = (struct lov_user_md_v1 *)&lumv3;
 405         int stripe_count;
 406         int rc;
 407         ENTRY;
 408
 409         rc = copy_from_user(&lumv3, lump, sizeof(struct lov_user_md_v1));
 410         if (rc)
 411                 RETURN(-EFAULT);
 412
 413         switch (lumv1->lmm_magic) {
 414         case LOV_USER_MAGIC_V3_SWABBED:
 415                 rc = copy_from_user(&lumv3, lump, sizeof(lumv3));
 416                 if (rc)
 417                         break;
 418                 /* fall through to swab */
 419         case LOV_USER_MAGIC_V1_SWABBED:
 420                 rc = lustre_swab_lov_user_md(lumv1);
 421                 break;
 422         case LOV_USER_MAGIC_V3:
 423                 rc = copy_from_user(&lumv3, lump, sizeof(lumv3));
 424                 /* fall through */
 425         case LOV_USER_MAGIC_V1:
 426                 break;
 427         default:
 428                 CERROR("bad lsm magic %08x\n", lumv1->lmm_magic);
 429                 RETURN(-EINVAL);
 430         }
 431         if (rc)
 432                 RETURN(rc);
 433
 434         /* in the rest of the tests, as *lumv1 and lumv3 have the same
 435          * fields, we use lumv1 to avoid code duplication */
 436
 437         if (lumv1->lmm_pattern == 0) {
 438                 lumv1->lmm_pattern = lov->desc.ld_pattern ?
 439                         lov->desc.ld_pattern : LOV_PATTERN_RAID0;
 440         }
 441
 442         if (lumv1->lmm_pattern != LOV_PATTERN_RAID0) {
 443                 CDEBUG(D_IOCTL, "bad userland stripe pattern: %#x\n",
 444                        lumv1->lmm_pattern);
 445                 RETURN(-EINVAL);
 446         }
 447
 448         /* 64kB is the largest common page size we see (ia64), and matches the
 449          * check in lfs */
 450         if (lumv1->lmm_stripe_size & (LOV_MIN_STRIPE_SIZE - 1)) {
 451                 CDEBUG(D_IOCTL, "stripe size %u not multiple of %u, fixing\n",
 452                        lumv1->lmm_stripe_size, LOV_MIN_STRIPE_SIZE);
 453                 lumv1->lmm_stripe_size = LOV_MIN_STRIPE_SIZE;
 454         }
 455
 456         if ((lumv1->lmm_stripe_offset >= lov->desc.ld_tgt_count) &&
 457             (lumv1->lmm_stripe_offset !=
 458              (typeof(lumv1->lmm_stripe_offset))(-1))) {
 459                 CDEBUG(D_IOCTL, "stripe offset %u > number of OSTs %u\n",
 460                        lumv1->lmm_stripe_offset, lov->desc.ld_tgt_count);
 461                 RETURN(-EINVAL);
 462         }
 463
 464         stripe_count = lov_get_stripecnt(lov, lumv1->lmm_stripe_count);
 465
 466         if (lumv1->lmm_magic == LOV_USER_MAGIC_V3) {
 467                 struct pool_desc *pool;
 468
 469                 pool = lov_find_pool(lov, lumv3.lmm_pool_name);
 470                 if (pool != NULL) {
 471                         if (lumv1->lmm_stripe_offset !=
 472                             (typeof(lumv1->lmm_stripe_offset))(-1)) {
 473                                 rc = lov_check_index_in_pool(
 474                                         lumv1->lmm_stripe_offset, pool);
 475                                 if (rc < 0) {
 476                                         lov_pool_putref(pool);
 477                                         RETURN(-EINVAL);
 478                                 }
 479                         }
 480
 481                         if (stripe_count > pool_tgt_count(pool))
 482                                 stripe_count = pool_tgt_count(pool);
 483
 484                         lov_pool_putref(pool);
 485                 }
 486         }
 487
 488         rc = lov_alloc_memmd(lsmp, stripe_count, lumv1->lmm_pattern,
 489                              lumv1->lmm_magic);
 490
 491         if (rc < 0)
 492                 RETURN(rc);
 493
 494         (*lsmp)->lsm_oinfo[0]->loi_ost_idx = lumv1->lmm_stripe_offset;
 495         (*lsmp)->lsm_stripe_size = lumv1->lmm_stripe_size;
 496
 497         if (lumv1->lmm_magic == LOV_USER_MAGIC_V3)
 498                 strncpy((*lsmp)->lsm_pool_name, lumv3.lmm_pool_name,
 499                         LOV_MAXPOOLNAME);
 500
 501         RETURN(0);
 502 }
 503
 504 int lov_setea(struct obd_export *exp, struct lov_stripe_md **lsmp,
 505               struct lov_user_md *lump)
 506 {
 507         int i;
 508         int rc;
 509         struct obd_export *oexp;
 510         struct lov_obd *lov = &exp->exp_obd->u.lov;
 511         obd_id last_id = 0;
 512         struct lov_user_ost_data_v1 *lmm_objects;
 513
 514         ENTRY;
 515
 516         if (lump->lmm_magic == LOV_USER_MAGIC_V3)
 517                 lmm_objects = ((struct lov_user_md_v3 *)lump)->lmm_objects;
 518         else
 519                 lmm_objects = lump->lmm_objects;
 520
 521         for (i = 0; i < lump->lmm_stripe_count; i++) {
 522                 __u32 len = sizeof(last_id);
 523                 oexp = lov->lov_tgts[lmm_objects[i].l_ost_idx]->ltd_exp;
 524                 rc = obd_get_info(oexp, sizeof(KEY_LAST_ID), KEY_LAST_ID,
 525                                   &len, &last_id, NULL);
 526                 if (rc)
 527                         RETURN(rc);
 528                 if (lmm_objects[i].l_object_id > last_id) {
 529                         CERROR("Setting EA for object > than last id on "
 530                                "ost idx %d "LPD64" > "LPD64" \n",
 531                                lmm_objects[i].l_ost_idx,
 532                                lmm_objects[i].l_object_id, last_id);
 533                         RETURN(-EINVAL);
 534                 }
 535         }
 536
 537         rc = lov_setstripe(exp, lsmp, lump);
 538         if (rc)
 539                 RETURN(rc);
 540
 541         for (i = 0; i < lump->lmm_stripe_count; i++) {
 542                 (*lsmp)->lsm_oinfo[i]->loi_ost_idx =
 543                         lmm_objects[i].l_ost_idx;
 544                 (*lsmp)->lsm_oinfo[i]->loi_id = lmm_objects[i].l_object_id;
 545                 (*lsmp)->lsm_oinfo[i]->loi_gr = lmm_objects[i].l_object_gr;
 546         }
 547         RETURN(0);
 548 }
 549
 550
 551 /* Retrieve object striping information.
 552  *
 553  * @lump is a pointer to an in-core struct with lmm_ost_count indicating
 554  * the maximum number of OST indices which will fit in the user buffer.
 555  * lmm_magic must be LOV_USER_MAGIC.
 556  */
 557 int lov_getstripe(struct obd_export *exp, struct lov_stripe_md *lsm,
 558                   struct lov_user_md *lump)
 559 {
 560         /* we use lov_user_md_v3 because it is larger than lov_user_md_v1 */
 561         struct lov_user_md_v3 lum;
 562         struct lov_mds_md *lmmk = NULL;
 563         int rc, lmm_size;
 564         int lum_size;
 565         ENTRY;
 566
 567         if (!lsm)
 568                 RETURN(-ENODATA);
 569         /* we only need the header part from user space to get lmm_magic and
 570          * lmm_stripe_count, (the header part is common to v1 and v3) */
 571         lum_size = sizeof(struct lov_user_md_v1);
 572         rc = copy_from_user(&lum, lump, lum_size);
 573         if (rc)
 574                 RETURN(-EFAULT);
 575         /* if v3 we just have to update the lum_size */
 576         if (lum.lmm_magic == LOV_USER_MAGIC_V3)
 577                 lum_size = sizeof(struct lov_user_md_v3);
 578
 579         if ((lum.lmm_magic != LOV_USER_MAGIC_V1) &&
 580             (lum.lmm_magic != LOV_USER_MAGIC_V3))
 581                 RETURN(-EINVAL);
 582
 583         if (lum.lmm_stripe_count &&
 584             (lum.lmm_stripe_count < lsm->lsm_stripe_count)) {
 585                 /* Return right size of stripe to user */
 586                 lum.lmm_stripe_count = lsm->lsm_stripe_count;
 587                 rc = copy_to_user(lump, &lum, lum_size);
 588                 RETURN(-EOVERFLOW);
 589         }
 590         rc = lov_packmd(exp, &lmmk, lsm);
 591         if (rc < 0)
 592                 RETURN(rc);
 593         lmm_size = rc;
 594         rc = 0;
 595
 596         /* FIXME: Bug 1185 - copy fields properly when structs change */
 597         /* struct lov_user_md_v3 and struct lov_mds_md_v3 must be the same */
 598         LASSERT(sizeof(lum) == sizeof(struct lov_mds_md_v3));
 599         LASSERT(sizeof(lum.lmm_objects[0]) == sizeof(lmmk->lmm_objects[0]));
 600
 601         if ((cpu_to_le32(LOV_MAGIC) != LOV_MAGIC) &&
 602             ((lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V1)) ||
 603             (lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V3)))) {
 604                 lustre_swab_lov_user_md_objects((struct lov_user_md*)lmmk);
 605                 lustre_swab_lov_mds_md(lmmk);
 606         }
 607         if (lum.lmm_magic == LOV_USER_MAGIC) {
 608                 /* User request for v1, we need skip lmm_pool_name */
 609                 if (lmmk->lmm_magic == LOV_MAGIC_V3) {
 610                         memmove(((struct lov_mds_md_v1*)lmmk)->lmm_objects,
 611                                 ((struct lov_mds_md_v3*)lmmk)->lmm_objects,
 612                                 lmmk->lmm_stripe_count *
 613                                 sizeof(struct lov_ost_data_v1));
 614                         lmm_size -= LOV_MAXPOOLNAME;
 615                 }
 616         } else {
 617                 /* if v3 we just have to update the lum_size */
 618                 lum_size = sizeof(struct lov_user_md_v3);
 619         }
 620         /* User wasn't expecting this many OST entries */
 621         if (lum.lmm_stripe_count == 0)
 622                 lmm_size = lum_size;
 623         else if (lum.lmm_stripe_count < lmmk->lmm_stripe_count)
 624                 RETURN(-EOVERFLOW);
 625         /*
 626          * Have a difference between lov_mds_md & lov_user_md.
 627          * So we have to re-order the data before copy to user.
 628          */
 629         lum.lmm_stripe_count = lmmk->lmm_stripe_count;
 630         ((struct lov_user_md*)lmmk)->lmm_stripe_offset = 0;
 631         ((struct lov_user_md*)lmmk)->lmm_stripe_count = lum.lmm_stripe_count;
 632         if (copy_to_user(lump, lmmk, lmm_size))
 633                 rc = -EFAULT;
 634
 635         /* Restore the LE endian to ensure obd_free_diskmd works well */
 636         if (cpu_to_le32(LOV_MAGIC) != LOV_MAGIC) {
 637                 lmmk->lmm_stripe_count = lum.lmm_stripe_count;
 638                 lustre_swab_lov_mds_md(lmmk);
 639         }
 640
 641         obd_free_diskmd(exp, &lmmk);
 642
 643         RETURN(rc);
 644 }