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 (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  30  * Use is subject to license terms.
  31  *
  32  * Copyright (c) 2011, 2012, Whamcloud, Inc.
  33  */
  34 /*
  35  * This file is part of Lustre, http://www.lustre.org/
  36  * Lustre is a trademark of Sun Microsystems, Inc.
  37  *
  38  * lustre/lov/lov_pack.c
  39  *
  40  * (Un)packing of OST/MDS requests
  41  *
  42  * Author: Andreas Dilger <adilger@clusterfs.com>
  43  */
  44
  45 #define DEBUG_SUBSYSTEM S_LOV
  46 #ifndef __KERNEL__
  47 #include <liblustre.h>
  48 #endif
  49
  50 #include <lustre_net.h>
  51 #include <obd.h>
  52 #include <obd_lov.h>
  53 #include <obd_class.h>
  54 #include <obd_support.h>
  55 #include <lustre/lustre_user.h>
  56
  57 #include "lov_internal.h"
  58
  59 static void lov_dump_lmm_common(int level, void *lmmp)
  60 {
  61         struct lov_mds_md *lmm = lmmp;
  62
  63         CDEBUG(level, "objid "LPX64", magic 0x%08x, pattern %#x\n",
  64                (__u64)le64_to_cpu(lmm->lmm_object_id),
  65                le32_to_cpu(lmm->lmm_magic),
  66                le32_to_cpu(lmm->lmm_pattern));
  67         CDEBUG(level,"stripe_size %u, stripe_count %u, layout_gen %u\n",
  68                le32_to_cpu(lmm->lmm_stripe_size),
  69                le16_to_cpu(lmm->lmm_stripe_count),
  70                le16_to_cpu(lmm->lmm_layout_gen));
  71 }
  72
  73 static void lov_dump_lmm_objects(int level, struct lov_ost_data *lod,
  74                                  int stripe_count)
  75 {
  76         int i;
  77
  78         if (stripe_count > LOV_V1_INSANE_STRIPE_COUNT) {
  79                 CDEBUG(level, "bad stripe_count %u > max_stripe_count %u\n",
  80                        stripe_count, LOV_V1_INSANE_STRIPE_COUNT);
  81         }
  82
  83         for (i = 0; i < stripe_count; ++i, ++lod) {
  84                 CDEBUG(level, "stripe %u idx %u subobj "LPX64"/"LPX64"\n", i,
  85                        le32_to_cpu(lod->l_ost_idx),
  86                        (__u64)le64_to_cpu(lod->l_object_seq),
  87                        (__u64)le64_to_cpu(lod->l_object_id));
  88         }
  89 }
  90
  91 void lov_dump_lmm_v1(int level, struct lov_mds_md_v1 *lmm)
  92 {
  93         lov_dump_lmm_common(level, lmm);
  94         lov_dump_lmm_objects(level, lmm->lmm_objects,
  95                              le16_to_cpu(lmm->lmm_stripe_count));
  96 }
  97
  98 void lov_dump_lmm_v3(int level, struct lov_mds_md_v3 *lmm)
  99 {
 100         lov_dump_lmm_common(level, lmm);
 101         CDEBUG(level,"pool_name "LOV_POOLNAMEF"\n", lmm->lmm_pool_name);
 102         lov_dump_lmm_objects(level, lmm->lmm_objects,
 103                              le16_to_cpu(lmm->lmm_stripe_count));
 104 }
 105
 106 void lov_dump_lmm(int level, void *lmm)
 107 {
 108         int magic;
 109
 110         magic = ((struct lov_mds_md_v1 *)(lmm))->lmm_magic;
 111         switch (magic) {
 112         case LOV_MAGIC_V1:
 113                 return lov_dump_lmm_v1(level, (struct lov_mds_md_v1 *)(lmm));
 114         case LOV_MAGIC_V3:
 115                 return lov_dump_lmm_v3(level, (struct lov_mds_md_v3 *)(lmm));
 116         default:
 117                 CERROR("Cannot recognize lmm_magic %x", magic);
 118         }
 119         return;
 120 }
 121
 122 #define LMM_ASSERT(test)                                                \
 123 do {                                                                    \
 124         if (!(test)) lov_dump_lmm(D_ERROR, lmm);                        \
 125         LASSERT(test); /* so we know what assertion failed */           \
 126 } while(0)
 127
 128 /* Pack LOV object metadata for disk storage.  It is packed in LE byte
 129  * order and is opaque to the networking layer.
 130  *
 131  * XXX In the future, this will be enhanced to get the EA size from the
 132  *     underlying OSC device(s) to get their EA sizes so we can stack
 133  *     LOVs properly.  For now lov_mds_md_size() just assumes one obd_id
 134  *     per stripe.
 135  */
 136 int lov_packmd(struct obd_export *exp, struct lov_mds_md **lmmp,
 137                struct lov_stripe_md *lsm)
 138 {
 139         struct obd_device *obd = class_exp2obd(exp);
 140         struct lov_obd *lov = &obd->u.lov;
 141         struct lov_mds_md_v1 *lmmv1;
 142         struct lov_mds_md_v3 *lmmv3;
 143         __u16 stripe_count;
 144         struct lov_ost_data_v1 *lmm_objects;
 145         int lmm_size, lmm_magic;
 146         int i;
 147         ENTRY;
 148
 149         if (lsm) {
 150                 lmm_magic = lsm->lsm_magic;
 151         } else {
 152                 if (lmmp && *lmmp)
 153                         lmm_magic = le32_to_cpu((*lmmp)->lmm_magic);
 154                 else
 155                         /* lsm == NULL and lmmp == NULL */
 156                         lmm_magic = LOV_MAGIC;
 157         }
 158
 159         if ((lmm_magic != LOV_MAGIC_V1) &&
 160             (lmm_magic != LOV_MAGIC_V3)) {
 161                 CERROR("bad mem LOV MAGIC: 0x%08X != 0x%08X nor 0x%08X\n",
 162                         lmm_magic, LOV_MAGIC_V1, LOV_MAGIC_V3);
 163                 RETURN(-EINVAL);
 164
 165         }
 166
 167         if (lsm) {
 168                 /* If we are just sizing the EA, limit the stripe count
 169                  * to the actual number of OSTs in this filesystem. */
 170                 if (!lmmp) {
 171                         stripe_count = lov_get_stripecnt(lov, lmm_magic,
 172                                                          lsm->lsm_stripe_count);
 173                         lsm->lsm_stripe_count = stripe_count;
 174                 } else {
 175                         stripe_count = lsm->lsm_stripe_count;
 176                 }
 177         } else {
 178                 /* No need to allocate more than maximum supported stripes.
 179                  * Anyway, this is pretty inaccurate since ld_tgt_count now
 180                  * represents max index and we should rely on the actual number
 181                  * of OSTs instead */
 182                 stripe_count = lov_mds_md_stripecnt(lov->lov_ocd.ocd_max_easize,
 183                                                     lmm_magic);
 184                 if (stripe_count > lov->desc.ld_tgt_count)
 185                         stripe_count = lov->desc.ld_tgt_count;
 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 = le16_to_cpu((*lmmp)->lmm_stripe_count);
 196                 lmm_size = lov_mds_md_size(stripe_count, lmm_magic);
 197                 OBD_FREE_LARGE(*lmmp, lmm_size);
 198                 *lmmp = NULL;
 199                 RETURN(0);
 200         }
 201
 202         if (!*lmmp) {
 203                 OBD_ALLOC_LARGE(*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_object_id = cpu_to_le64(lsm->lsm_object_id);
 225         lmmv1->lmm_object_seq = cpu_to_le64(lsm->lsm_object_seq);
 226         lmmv1->lmm_stripe_size = cpu_to_le32(lsm->lsm_stripe_size);
 227         lmmv1->lmm_stripe_count = cpu_to_le16(stripe_count);
 228         lmmv1->lmm_pattern = cpu_to_le32(lsm->lsm_pattern);
 229         lmmv1->lmm_layout_gen = cpu_to_le16(lsm->lsm_layout_gen);
 230         if (lsm->lsm_magic == LOV_MAGIC_V3) {
 231                 strncpy(lmmv3->lmm_pool_name, lsm->lsm_pool_name,
 232                         LOV_MAXPOOLNAME);
 233                 lmm_objects = lmmv3->lmm_objects;
 234         } else {
 235                 lmm_objects = lmmv1->lmm_objects;
 236         }
 237
 238         for (i = 0; i < stripe_count; i++) {
 239                 struct lov_oinfo *loi = lsm->lsm_oinfo[i];
 240                 /* XXX LOV STACKING call down to osc_packmd() to do packing */
 241                 LASSERTF(loi->loi_id, "lmm_oid "LPU64" stripe %u/%u idx %u\n",
 242                          lmmv1->lmm_object_id, i, stripe_count, loi->loi_ost_idx);
 243                 lmm_objects[i].l_object_id = cpu_to_le64(loi->loi_id);
 244                 lmm_objects[i].l_object_seq = cpu_to_le64(loi->loi_seq);
 245                 lmm_objects[i].l_ost_gen = cpu_to_le32(loi->loi_ost_gen);
 246                 lmm_objects[i].l_ost_idx = cpu_to_le32(loi->loi_ost_idx);
 247         }
 248
 249         RETURN(lmm_size);
 250 }
 251
 252 /* Find the max stripecount we should use */
 253 __u16 lov_get_stripecnt(struct lov_obd *lov, __u32 magic, __u16 stripe_count)
 254 {
 255         __u32 max_stripes = LOV_MAX_STRIPE_COUNT_OLD;
 256
 257         if (!stripe_count)
 258                 stripe_count = lov->desc.ld_default_stripe_count;
 259         if (stripe_count > lov->desc.ld_active_tgt_count)
 260                 stripe_count = lov->desc.ld_active_tgt_count;
 261         if (!stripe_count)
 262                 stripe_count = 1;
 263
 264         /* stripe count is based on whether ldiskfs can handle
 265          * larger EA sizes */
 266         if (lov->lov_ocd.ocd_connect_flags & OBD_CONNECT_MAX_EASIZE &&
 267             lov->lov_ocd.ocd_max_easize)
 268                 max_stripes = lov_mds_md_stripecnt(lov->lov_ocd.ocd_max_easize,
 269                                                    magic);
 270
 271         if (stripe_count > max_stripes)
 272                 stripe_count = max_stripes;
 273
 274         return stripe_count;
 275 }
 276
 277
 278 static int lov_verify_lmm(void *lmm, int lmm_bytes, __u16 *stripe_count)
 279 {
 280         int rc;
 281
 282         if (lsm_op_find(le32_to_cpu(*(__u32 *)lmm)) == NULL) {
 283                 char *buffer;
 284                 int sz;
 285
 286                 CERROR("bad disk LOV MAGIC: 0x%08X; dumping LMM (size=%d):\n",
 287                        le32_to_cpu(*(__u32 *)lmm), lmm_bytes);
 288                 sz = lmm_bytes * 2 + 1;
 289                 OBD_ALLOC_LARGE(buffer, sz);
 290                 if (buffer != NULL) {
 291                         int i;
 292
 293                         for (i = 0; i < lmm_bytes; i++)
 294                                 sprintf(buffer+2*i, "%.2X", ((char *)lmm)[i]);
 295                         buffer[sz] = '\0';
 296                         CERROR("%s\n", buffer);
 297                         OBD_FREE_LARGE(buffer, sz);
 298                 }
 299                 return -EINVAL;
 300         }
 301         rc = lsm_op_find(le32_to_cpu(*(__u32 *)lmm))->lsm_lmm_verify(lmm,
 302                                      lmm_bytes, stripe_count);
 303         return rc;
 304 }
 305
 306 int lov_alloc_memmd(struct lov_stripe_md **lsmp, __u16 stripe_count,
 307                     int pattern, int magic)
 308 {
 309         int i, lsm_size;
 310         ENTRY;
 311
 312         CDEBUG(D_INFO, "alloc lsm, stripe_count %d\n", stripe_count);
 313
 314         *lsmp = lsm_alloc_plain(stripe_count, &lsm_size);
 315         if (!*lsmp) {
 316                 CERROR("can't allocate lsmp stripe_count %d\n", stripe_count);
 317                 RETURN(-ENOMEM);
 318         }
 319
 320         cfs_spin_lock_init(&(*lsmp)->lsm_lock);
 321         (*lsmp)->lsm_magic = magic;
 322         (*lsmp)->lsm_stripe_count = stripe_count;
 323         (*lsmp)->lsm_maxbytes = LUSTRE_STRIPE_MAXBYTES * stripe_count;
 324         (*lsmp)->lsm_pattern = pattern;
 325         (*lsmp)->lsm_pool_name[0] = '\0';
 326         (*lsmp)->lsm_layout_gen = 0;
 327         (*lsmp)->lsm_oinfo[0]->loi_ost_idx = ~0;
 328
 329         for (i = 0; i < stripe_count; i++)
 330                 loi_init((*lsmp)->lsm_oinfo[i]);
 331
 332         RETURN(lsm_size);
 333 }
 334
 335 void lov_free_memmd(struct lov_stripe_md **lsmp)
 336 {
 337         struct lov_stripe_md *lsm = *lsmp;
 338
 339         LASSERT(lsm_op_find(lsm->lsm_magic) != NULL);
 340         lsm_op_find(lsm->lsm_magic)->lsm_free(lsm);
 341
 342         *lsmp = NULL;
 343 }
 344
 345
 346 /* Unpack LOV object metadata from disk storage.  It is packed in LE byte
 347  * order and is opaque to the networking layer.
 348  */
 349 int lov_unpackmd(struct obd_export *exp,  struct lov_stripe_md **lsmp,
 350                  struct lov_mds_md *lmm, int lmm_bytes)
 351 {
 352         struct obd_device *obd = class_exp2obd(exp);
 353         struct lov_obd *lov = &obd->u.lov;
 354         int rc = 0, lsm_size;
 355         __u16 stripe_count;
 356         __u32 magic;
 357         ENTRY;
 358
 359         /* If passed an MDS struct use values from there, otherwise defaults */
 360         if (lmm) {
 361                 rc = lov_verify_lmm(lmm, lmm_bytes, &stripe_count);
 362                 if (rc)
 363                         RETURN(rc);
 364                 magic = le32_to_cpu(lmm->lmm_magic);
 365         } else {
 366                 magic = LOV_MAGIC;
 367                 stripe_count = lov_get_stripecnt(lov, magic, 0);
 368         }
 369
 370         /* If we aren't passed an lsmp struct, we just want the size */
 371         if (!lsmp) {
 372                 /* XXX LOV STACKING call into osc for sizes */
 373                 LBUG();
 374                 RETURN(lov_stripe_md_size(stripe_count));
 375         }
 376         /* If we are passed an allocated struct but nothing to unpack, free */
 377         if (*lsmp && !lmm) {
 378                 lov_free_memmd(lsmp);
 379                 RETURN(0);
 380         }
 381
 382         lsm_size = lov_alloc_memmd(lsmp, stripe_count, LOV_PATTERN_RAID0,
 383                                    magic);
 384         if (lsm_size < 0)
 385                 RETURN(lsm_size);
 386
 387         /* If we are passed a pointer but nothing to unpack, we only alloc */
 388         if (!lmm)
 389                 RETURN(lsm_size);
 390
 391         LASSERT(lsm_op_find(magic) != NULL);
 392         rc = lsm_op_find(magic)->lsm_unpackmd(lov, *lsmp, lmm);
 393         if (rc) {
 394                 lov_free_memmd(lsmp);
 395                 RETURN(rc);
 396         }
 397
 398         RETURN(lsm_size);
 399 }
 400
 401 static int __lov_setstripe(struct obd_export *exp, int max_lmm_size,
 402                            struct lov_stripe_md **lsmp,
 403                            struct lov_user_md *lump)
 404 {
 405         struct obd_device *obd = class_exp2obd(exp);
 406         struct lov_obd *lov = &obd->u.lov;
 407         char buffer[sizeof(struct lov_user_md_v3)];
 408         struct lov_user_md_v3 *lumv3 = (struct lov_user_md_v3 *)&buffer[0];
 409         struct lov_user_md_v1 *lumv1 = (struct lov_user_md_v1 *)&buffer[0];
 410         int lmm_magic;
 411         __u16 stripe_count;
 412         int rc;
 413         ENTRY;
 414
 415         rc = lov_lum_swab_if_needed(lumv3, &lmm_magic, lump);
 416         if (rc)
 417                 RETURN(rc);
 418
 419         /* in the rest of the tests, as *lumv1 and lumv3 have the same
 420          * fields, we use lumv1 to avoid code duplication */
 421
 422         if (lumv1->lmm_pattern == 0) {
 423                 lumv1->lmm_pattern = lov->desc.ld_pattern ?
 424                         lov->desc.ld_pattern : LOV_PATTERN_RAID0;
 425         }
 426
 427         if (lumv1->lmm_pattern != LOV_PATTERN_RAID0) {
 428                 CDEBUG(D_IOCTL, "bad userland stripe pattern: %#x\n",
 429                        lumv1->lmm_pattern);
 430                 RETURN(-EINVAL);
 431         }
 432
 433         /* 64kB is the largest common page size we see (ia64), and matches the
 434          * check in lfs */
 435         if (lumv1->lmm_stripe_size & (LOV_MIN_STRIPE_SIZE - 1)) {
 436                 CDEBUG(D_IOCTL, "stripe size %u not multiple of %u, fixing\n",
 437                        lumv1->lmm_stripe_size, LOV_MIN_STRIPE_SIZE);
 438                 lumv1->lmm_stripe_size = LOV_MIN_STRIPE_SIZE;
 439         }
 440
 441         if ((lumv1->lmm_stripe_offset >= lov->desc.ld_tgt_count) &&
 442             (lumv1->lmm_stripe_offset !=
 443              (typeof(lumv1->lmm_stripe_offset))(-1))) {
 444                 CDEBUG(D_IOCTL, "stripe offset %u > number of OSTs %u\n",
 445                        lumv1->lmm_stripe_offset, lov->desc.ld_tgt_count);
 446                 RETURN(-EINVAL);
 447         }
 448         stripe_count = lov_get_stripecnt(lov, lmm_magic,
 449                                          lumv1->lmm_stripe_count);
 450
 451         if (max_lmm_size) {
 452                 int max_stripes = (max_lmm_size -
 453                                    lov_mds_md_size(0, lmm_magic)) /
 454                                    sizeof(struct lov_ost_data_v1);
 455                 if (unlikely(max_stripes < stripe_count)) {
 456                         CDEBUG(D_IOCTL, "stripe count reset from %d to %d\n",
 457                                stripe_count, max_stripes);
 458                         stripe_count = max_stripes;
 459                 }
 460         }
 461
 462         if (lmm_magic == LOV_USER_MAGIC_V3) {
 463                 struct pool_desc *pool;
 464
 465                 pool = lov_find_pool(lov, lumv3->lmm_pool_name);
 466                 if (pool != NULL) {
 467                         if (lumv3->lmm_stripe_offset !=
 468                             (typeof(lumv3->lmm_stripe_offset))(-1)) {
 469                                 rc = lov_check_index_in_pool(
 470                                         lumv3->lmm_stripe_offset, pool);
 471                                 if (rc < 0) {
 472                                         lov_pool_putref(pool);
 473                                         RETURN(-EINVAL);
 474                                 }
 475                         }
 476
 477                         if (stripe_count > pool_tgt_count(pool))
 478                                 stripe_count = pool_tgt_count(pool);
 479
 480                         lov_pool_putref(pool);
 481                 }
 482         }
 483
 484         rc = lov_alloc_memmd(lsmp, stripe_count, lumv1->lmm_pattern, lmm_magic);
 485
 486         if (rc >= 0) {
 487                 (*lsmp)->lsm_oinfo[0]->loi_ost_idx = lumv1->lmm_stripe_offset;
 488                 (*lsmp)->lsm_stripe_size = lumv1->lmm_stripe_size;
 489                 if (lmm_magic == LOV_USER_MAGIC_V3)
 490                         strncpy((*lsmp)->lsm_pool_name, lumv3->lmm_pool_name,
 491                                 LOV_MAXPOOLNAME);
 492                 rc = 0;
 493         }
 494
 495         RETURN(rc);
 496 }
 497
 498 /* Configure object striping information on a new file.
 499  *
 500  * @lmmu is a pointer to a user struct with one or more of the fields set to
 501  * indicate the application preference: lmm_stripe_count, lmm_stripe_size,
 502  * lmm_stripe_offset, and lmm_stripe_pattern.  lmm_magic must be LOV_MAGIC.
 503  * @lsmp is a pointer to an in-core stripe MD that needs to be filled in.
 504  */
 505 int lov_setstripe(struct obd_export *exp, int max_lmm_size,
 506                   struct lov_stripe_md **lsmp, struct lov_user_md *lump)
 507 {
 508         int rc;
 509         mm_segment_t seg;
 510
 511         seg = get_fs();
 512         set_fs(KERNEL_DS);
 513
 514         rc = __lov_setstripe(exp, max_lmm_size, lsmp, lump);
 515         set_fs(seg);
 516         RETURN(rc);
 517 }
 518
 519 int lov_setea(struct obd_export *exp, struct lov_stripe_md **lsmp,
 520               struct lov_user_md *lump)
 521 {
 522         int i;
 523         int rc;
 524         struct obd_export *oexp;
 525         struct lov_obd *lov = &exp->exp_obd->u.lov;
 526         obd_id last_id = 0;
 527         struct lov_user_ost_data_v1 *lmm_objects;
 528
 529         ENTRY;
 530
 531         if (lump->lmm_magic == LOV_USER_MAGIC_V3)
 532                 lmm_objects = ((struct lov_user_md_v3 *)lump)->lmm_objects;
 533         else
 534                 lmm_objects = lump->lmm_objects;
 535
 536         for (i = 0; i < lump->lmm_stripe_count; i++) {
 537                 __u32 len = sizeof(last_id);
 538                 oexp = lov->lov_tgts[lmm_objects[i].l_ost_idx]->ltd_exp;
 539                 rc = obd_get_info(oexp, sizeof(KEY_LAST_ID), KEY_LAST_ID,
 540                                   &len, &last_id, NULL);
 541                 if (rc)
 542                         RETURN(rc);
 543                 if (lmm_objects[i].l_object_id > last_id) {
 544                         CERROR("Setting EA for object > than last id on "
 545                                "ost idx %d "LPD64" > "LPD64" \n",
 546                                lmm_objects[i].l_ost_idx,
 547                                lmm_objects[i].l_object_id, last_id);
 548                         RETURN(-EINVAL);
 549                 }
 550         }
 551
 552         rc = lov_setstripe(exp, 0, lsmp, lump);
 553         if (rc)
 554                 RETURN(rc);
 555
 556         for (i = 0; i < lump->lmm_stripe_count; i++) {
 557                 (*lsmp)->lsm_oinfo[i]->loi_ost_idx =
 558                         lmm_objects[i].l_ost_idx;
 559                 (*lsmp)->lsm_oinfo[i]->loi_id = lmm_objects[i].l_object_id;
 560                 (*lsmp)->lsm_oinfo[i]->loi_seq = lmm_objects[i].l_object_seq;
 561         }
 562         RETURN(0);
 563 }
 564
 565
 566 /* Retrieve object striping information.
 567  *
 568  * @lump is a pointer to an in-core struct with lmm_ost_count indicating
 569  * the maximum number of OST indices which will fit in the user buffer.
 570  * lmm_magic must be LOV_USER_MAGIC.
 571  */
 572 int lov_getstripe(struct obd_export *exp, struct lov_stripe_md *lsm,
 573                   struct lov_user_md *lump)
 574 {
 575         /*
 576          * XXX huge struct allocated on stack.
 577          */
 578         /* we use lov_user_md_v3 because it is larger than lov_user_md_v1 */
 579         struct lov_user_md_v3 lum;
 580         struct lov_mds_md *lmmk = NULL;
 581         int rc, lmm_size;
 582         int lum_size;
 583         mm_segment_t seg;
 584         ENTRY;
 585
 586         if (!lsm)
 587                 RETURN(-ENODATA);
 588
 589         /*
 590          * "Switch to kernel segment" to allow copying from kernel space by
 591          * copy_{to,from}_user().
 592          */
 593         seg = get_fs();
 594         set_fs(KERNEL_DS);
 595
 596         /* we only need the header part from user space to get lmm_magic and
 597          * lmm_stripe_count, (the header part is common to v1 and v3) */
 598         lum_size = sizeof(struct lov_user_md_v1);
 599         if (cfs_copy_from_user(&lum, lump, lum_size))
 600                 GOTO(out_set, rc = -EFAULT);
 601         else if ((lum.lmm_magic != LOV_USER_MAGIC) &&
 602                  (lum.lmm_magic != LOV_USER_MAGIC_V3))
 603                 GOTO(out_set, rc = -EINVAL);
 604
 605         if (lum.lmm_stripe_count &&
 606             (lum.lmm_stripe_count < lsm->lsm_stripe_count)) {
 607                 /* Return right size of stripe to user */
 608                 lum.lmm_stripe_count = lsm->lsm_stripe_count;
 609                 rc = cfs_copy_to_user(lump, &lum, lum_size);
 610                 GOTO(out_set, rc = -EOVERFLOW);
 611         }
 612         rc = lov_packmd(exp, &lmmk, lsm);
 613         if (rc < 0)
 614                 GOTO(out_set, rc);
 615         lmm_size = rc;
 616         rc = 0;
 617
 618         /* FIXME: Bug 1185 - copy fields properly when structs change */
 619         /* struct lov_user_md_v3 and struct lov_mds_md_v3 must be the same */
 620         CLASSERT(sizeof(lum) == sizeof(struct lov_mds_md_v3));
 621         CLASSERT(sizeof lum.lmm_objects[0] == sizeof lmmk->lmm_objects[0]);
 622
 623         if ((cpu_to_le32(LOV_MAGIC) != LOV_MAGIC) &&
 624             ((lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V1)) ||
 625             (lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V3)))) {
 626                 lustre_swab_lov_mds_md(lmmk);
 627                 lustre_swab_lov_user_md_objects(
 628                                 (struct lov_user_ost_data*)lmmk->lmm_objects,
 629                                 lmmk->lmm_stripe_count);
 630         }
 631         if (lum.lmm_magic == LOV_USER_MAGIC) {
 632                 /* User request for v1, we need skip lmm_pool_name */
 633                 if (lmmk->lmm_magic == LOV_MAGIC_V3) {
 634                         memmove((char*)(&lmmk->lmm_stripe_count) +
 635                                 sizeof(lmmk->lmm_stripe_count),
 636                                 ((struct lov_mds_md_v3*)lmmk)->lmm_objects,
 637                                 lmmk->lmm_stripe_count *
 638                                 sizeof(struct lov_ost_data_v1));
 639                         lmm_size -= LOV_MAXPOOLNAME;
 640                 }
 641         } else {
 642                 /* if v3 we just have to update the lum_size */
 643                 lum_size = sizeof(struct lov_user_md_v3);
 644         }
 645
 646         /* User wasn't expecting this many OST entries */
 647         if (lum.lmm_stripe_count == 0)
 648                 lmm_size = lum_size;
 649         else if (lum.lmm_stripe_count < lmmk->lmm_stripe_count)
 650                 GOTO(out_set, rc = -EOVERFLOW);
 651         /*
 652          * Have a difference between lov_mds_md & lov_user_md.
 653          * So we have to re-order the data before copy to user.
 654          */
 655         lum.lmm_stripe_count = lmmk->lmm_stripe_count;
 656         lum.u.lum_layout_gen = lmmk->lmm_layout_gen;
 657         ((struct lov_user_md*)lmmk)->u.lum_layout_gen = lum.u.lum_layout_gen;
 658         ((struct lov_user_md*)lmmk)->lmm_stripe_count = lum.lmm_stripe_count;
 659         if (cfs_copy_to_user(lump, lmmk, lmm_size))
 660                 rc = -EFAULT;
 661
 662         obd_free_diskmd(exp, &lmmk);
 663 out_set:
 664         set_fs(seg);
 665         RETURN(rc);
 666 }