lustre/lov/lov_pack.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) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, 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  * 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, layout_gen %u\n",
  66                le32_to_cpu(lmm->lmm_stripe_size),
  67                le16_to_cpu(lmm->lmm_stripe_count),
  68                le16_to_cpu(lmm->lmm_layout_gen));
  69 }
  70
  71 static void lov_dump_lmm_objects(int level, struct lov_ost_data *lod,
  72                                  int stripe_count)
  73 {
  74         int i;
  75
  76         if (stripe_count > LOV_V1_INSANE_STRIPE_COUNT) {
  77                 CDEBUG(level, "bad stripe_count %u > max_stripe_count %u\n",
  78                        stripe_count, LOV_V1_INSANE_STRIPE_COUNT);
  79         }
  80
  81         for (i = 0; i < stripe_count; ++i, ++lod) {
  82                 CDEBUG(level, "stripe %u idx %u subobj "LPX64"/"LPX64"\n", i,
  83                        le32_to_cpu(lod->l_ost_idx),
  84                        (__u64)le64_to_cpu(lod->l_object_seq),
  85                        (__u64)le64_to_cpu(lod->l_object_id));
  86         }
  87 }
  88
  89 void lov_dump_lmm_v1(int level, struct lov_mds_md_v1 *lmm)
  90 {
  91         lov_dump_lmm_common(level, lmm);
  92         lov_dump_lmm_objects(level, lmm->lmm_objects,
  93                              le16_to_cpu(lmm->lmm_stripe_count));
  94 }
  95
  96 void lov_dump_lmm_v3(int level, struct lov_mds_md_v3 *lmm)
  97 {
  98         lov_dump_lmm_common(level, lmm);
  99         CDEBUG(level,"pool_name "LOV_POOLNAMEF"\n", lmm->lmm_pool_name);
 100         lov_dump_lmm_objects(level, lmm->lmm_objects,
 101                              le16_to_cpu(lmm->lmm_stripe_count));
 102 }
 103
 104 void lov_dump_lmm(int level, void *lmm)
 105 {
 106         int magic;
 107
 108         magic = ((struct lov_mds_md_v1 *)(lmm))->lmm_magic;
 109         switch (magic) {
 110         case LOV_MAGIC_V1:
 111                 return lov_dump_lmm_v1(level, (struct lov_mds_md_v1 *)(lmm));
 112         case LOV_MAGIC_V3:
 113                 return lov_dump_lmm_v3(level, (struct lov_mds_md_v3 *)(lmm));
 114         default:
 115                 CERROR("Cannot recognize lmm_magic %x", magic);
 116         }
 117         return;
 118 }
 119
 120 #define LMM_ASSERT(test)                                                \
 121 do {                                                                    \
 122         if (!(test)) lov_dump_lmm(D_ERROR, lmm);                        \
 123         LASSERT(test); /* so we know what assertion failed */           \
 124 } while(0)
 125
 126 /* Pack LOV object metadata for disk storage.  It is packed in LE byte
 127  * order and is opaque to the networking layer.
 128  *
 129  * XXX In the future, this will be enhanced to get the EA size from the
 130  *     underlying OSC device(s) to get their EA sizes so we can stack
 131  *     LOVs properly.  For now lov_mds_md_size() just assumes one obd_id
 132  *     per stripe.
 133  */
 134 int lov_packmd(struct obd_export *exp, struct lov_mds_md **lmmp,
 135                struct lov_stripe_md *lsm)
 136 {
 137         struct obd_device *obd = class_exp2obd(exp);
 138         struct lov_obd *lov = &obd->u.lov;
 139         struct lov_mds_md_v1 *lmmv1;
 140         struct lov_mds_md_v3 *lmmv3;
 141         __u16 stripe_count;
 142         struct lov_ost_data_v1 *lmm_objects;
 143         int lmm_size, lmm_magic;
 144         int i;
 145         int cplen = 0;
 146         ENTRY;
 147
 148         if (lsm) {
 149                 lmm_magic = lsm->lsm_magic;
 150         } else {
 151                 if (lmmp && *lmmp)
 152                         lmm_magic = le32_to_cpu((*lmmp)->lmm_magic);
 153                 else
 154                         /* lsm == NULL and lmmp == NULL */
 155                         lmm_magic = LOV_MAGIC;
 156         }
 157
 158         if ((lmm_magic != LOV_MAGIC_V1) &&
 159             (lmm_magic != LOV_MAGIC_V3)) {
 160                 CERROR("bad mem LOV MAGIC: 0x%08X != 0x%08X nor 0x%08X\n",
 161                         lmm_magic, LOV_MAGIC_V1, LOV_MAGIC_V3);
 162                 RETURN(-EINVAL);
 163
 164         }
 165
 166         if (lsm) {
 167                 /* If we are just sizing the EA, limit the stripe count
 168                  * to the actual number of OSTs in this filesystem. */
 169                 if (!lmmp) {
 170                         stripe_count = lov_get_stripecnt(lov, lmm_magic,
 171                                                          lsm->lsm_stripe_count);
 172                         lsm->lsm_stripe_count = stripe_count;
 173                 } else {
 174                         stripe_count = lsm->lsm_stripe_count;
 175                 }
 176         } else {
 177                 /* No need to allocate more than maximum supported stripes.
 178                  * Anyway, this is pretty inaccurate since ld_tgt_count now
 179                  * represents max index and we should rely on the actual number
 180                  * of OSTs instead */
 181                 stripe_count = lov_mds_md_stripecnt(lov->lov_ocd.ocd_max_easize,
 182                                                     lmm_magic);
 183                 if (stripe_count > lov->desc.ld_tgt_count)
 184                         stripe_count = lov->desc.ld_tgt_count;
 185         }
 186
 187         /* XXX LOV STACKING call into osc for sizes */
 188         lmm_size = lov_mds_md_size(stripe_count, lmm_magic);
 189
 190         if (!lmmp)
 191                 RETURN(lmm_size);
 192
 193         if (*lmmp && !lsm) {
 194                 stripe_count = le16_to_cpu((*lmmp)->lmm_stripe_count);
 195                 lmm_size = lov_mds_md_size(stripe_count, lmm_magic);
 196                 OBD_FREE_LARGE(*lmmp, lmm_size);
 197                 *lmmp = NULL;
 198                 RETURN(0);
 199         }
 200
 201         if (!*lmmp) {
 202                 OBD_ALLOC_LARGE(*lmmp, lmm_size);
 203                 if (!*lmmp)
 204                         RETURN(-ENOMEM);
 205         }
 206
 207         CDEBUG(D_INFO, "lov_packmd: LOV_MAGIC 0x%08X, lmm_size = %d \n",
 208                lmm_magic, lmm_size);
 209
 210         lmmv1 = *lmmp;
 211         lmmv3 = (struct lov_mds_md_v3 *)*lmmp;
 212         if (lmm_magic == LOV_MAGIC_V3)
 213                 lmmv3->lmm_magic = cpu_to_le32(LOV_MAGIC_V3);
 214         else
 215                 lmmv1->lmm_magic = cpu_to_le32(LOV_MAGIC_V1);
 216
 217         if (!lsm)
 218                 RETURN(lmm_size);
 219
 220         /* lmmv1 and lmmv3 point to the same struct and have the
 221          * same first fields
 222          */
 223         lmmv1->lmm_object_id = cpu_to_le64(lsm->lsm_object_id);
 224         lmmv1->lmm_object_seq = cpu_to_le64(lsm->lsm_object_seq);
 225         lmmv1->lmm_stripe_size = cpu_to_le32(lsm->lsm_stripe_size);
 226         lmmv1->lmm_stripe_count = cpu_to_le16(stripe_count);
 227         lmmv1->lmm_pattern = cpu_to_le32(lsm->lsm_pattern);
 228         lmmv1->lmm_layout_gen = cpu_to_le16(lsm->lsm_layout_gen);
 229         if (lsm->lsm_magic == LOV_MAGIC_V3) {
 230                 cplen = strlcpy(lmmv3->lmm_pool_name, lsm->lsm_pool_name,
 231                                 sizeof(lmmv3->lmm_pool_name));
 232                 if (cplen >= sizeof(lmmv3->lmm_pool_name))
 233                         RETURN(-E2BIG);
 234                 lmm_objects = lmmv3->lmm_objects;
 235         } else {
 236                 lmm_objects = lmmv1->lmm_objects;
 237         }
 238
 239         for (i = 0; i < stripe_count; i++) {
 240                 struct lov_oinfo *loi = lsm->lsm_oinfo[i];
 241                 /* XXX LOV STACKING call down to osc_packmd() to do packing */
 242                 LASSERTF(loi->loi_id, "lmm_oid "LPU64" stripe %u/%u idx %u\n",
 243                          lmmv1->lmm_object_id, i, stripe_count, loi->loi_ost_idx);
 244                 lmm_objects[i].l_object_id = cpu_to_le64(loi->loi_id);
 245                 lmm_objects[i].l_object_seq = cpu_to_le64(loi->loi_seq);
 246                 lmm_objects[i].l_ost_gen = cpu_to_le32(loi->loi_ost_gen);
 247                 lmm_objects[i].l_ost_idx = cpu_to_le32(loi->loi_ost_idx);
 248         }
 249
 250         RETURN(lmm_size);
 251 }
 252
 253 /* Find the max stripecount we should use */
 254 __u16 lov_get_stripecnt(struct lov_obd *lov, __u32 magic, __u16 stripe_count)
 255 {
 256         __u32 max_stripes = LOV_MAX_STRIPE_COUNT_OLD;
 257
 258         if (!stripe_count)
 259                 stripe_count = lov->desc.ld_default_stripe_count;
 260         if (stripe_count > lov->desc.ld_active_tgt_count)
 261                 stripe_count = lov->desc.ld_active_tgt_count;
 262         if (!stripe_count)
 263                 stripe_count = 1;
 264
 265         /* stripe count is based on whether ldiskfs can handle
 266          * larger EA sizes */
 267         if (lov->lov_ocd.ocd_connect_flags & OBD_CONNECT_MAX_EASIZE &&
 268             lov->lov_ocd.ocd_max_easize)
 269                 max_stripes = lov_mds_md_stripecnt(lov->lov_ocd.ocd_max_easize,
 270                                                    magic);
 271
 272         if (stripe_count > max_stripes)
 273                 stripe_count = max_stripes;
 274
 275         return stripe_count;
 276 }
 277
 278
 279 static int lov_verify_lmm(void *lmm, int lmm_bytes, __u16 *stripe_count)
 280 {
 281         int rc;
 282
 283         if (lsm_op_find(le32_to_cpu(*(__u32 *)lmm)) == NULL) {
 284                 char *buffer;
 285                 int sz;
 286
 287                 CERROR("bad disk LOV MAGIC: 0x%08X; dumping LMM (size=%d):\n",
 288                        le32_to_cpu(*(__u32 *)lmm), lmm_bytes);
 289                 sz = lmm_bytes * 2 + 1;
 290                 OBD_ALLOC_LARGE(buffer, sz);
 291                 if (buffer != NULL) {
 292                         int i;
 293
 294                         for (i = 0; i < lmm_bytes; i++)
 295                                 sprintf(buffer+2*i, "%.2X", ((char *)lmm)[i]);
 296                         buffer[sz - 1] = '\0';
 297                         CERROR("%s\n", buffer);
 298                         OBD_FREE_LARGE(buffer, sz);
 299                 }
 300                 return -EINVAL;
 301         }
 302         rc = lsm_op_find(le32_to_cpu(*(__u32 *)lmm))->lsm_lmm_verify(lmm,
 303                                      lmm_bytes, stripe_count);
 304         return rc;
 305 }
 306
 307 int lov_alloc_memmd(struct lov_stripe_md **lsmp, __u16 stripe_count,
 308                     int pattern, int magic)
 309 {
 310         int i, lsm_size;
 311         ENTRY;
 312
 313         CDEBUG(D_INFO, "alloc lsm, stripe_count %d\n", stripe_count);
 314
 315         *lsmp = lsm_alloc_plain(stripe_count, &lsm_size);
 316         if (!*lsmp) {
 317                 CERROR("can't allocate lsmp stripe_count %d\n", stripe_count);
 318                 RETURN(-ENOMEM);
 319         }
 320
 321         cfs_atomic_set(&(*lsmp)->lsm_refc, 1);
 322         spin_lock_init(&(*lsmp)->lsm_lock);
 323         (*lsmp)->lsm_magic = magic;
 324         (*lsmp)->lsm_stripe_count = stripe_count;
 325         (*lsmp)->lsm_maxbytes = LUSTRE_STRIPE_MAXBYTES * stripe_count;
 326         (*lsmp)->lsm_pattern = pattern;
 327         (*lsmp)->lsm_pool_name[0] = '\0';
 328         (*lsmp)->lsm_layout_gen = 0;
 329         (*lsmp)->lsm_oinfo[0]->loi_ost_idx = ~0;
 330
 331         for (i = 0; i < stripe_count; i++)
 332                 loi_init((*lsmp)->lsm_oinfo[i]);
 333
 334         RETURN(lsm_size);
 335 }
 336
 337 int lov_free_memmd(struct lov_stripe_md **lsmp)
 338 {
 339         struct lov_stripe_md *lsm = *lsmp;
 340         int refc;
 341
 342         *lsmp = NULL;
 343         LASSERT(cfs_atomic_read(&lsm->lsm_refc) > 0);
 344         if ((refc = cfs_atomic_dec_return(&lsm->lsm_refc)) == 0) {
 345                 LASSERT(lsm_op_find(lsm->lsm_magic) != NULL);
 346                 lsm_op_find(lsm->lsm_magic)->lsm_free(lsm);
 347         }
 348         return refc;
 349 }
 350
 351
 352 /* Unpack LOV object metadata from disk storage.  It is packed in LE byte
 353  * order and is opaque to the networking layer.
 354  */
 355 int lov_unpackmd(struct obd_export *exp,  struct lov_stripe_md **lsmp,
 356                  struct lov_mds_md *lmm, int lmm_bytes)
 357 {
 358         struct obd_device *obd = class_exp2obd(exp);
 359         struct lov_obd *lov = &obd->u.lov;
 360         int rc = 0, lsm_size;
 361         __u16 stripe_count;
 362         __u32 magic;
 363         ENTRY;
 364
 365         /* If passed an MDS struct use values from there, otherwise defaults */
 366         if (lmm) {
 367                 rc = lov_verify_lmm(lmm, lmm_bytes, &stripe_count);
 368                 if (rc)
 369                         RETURN(rc);
 370                 magic = le32_to_cpu(lmm->lmm_magic);
 371         } else {
 372                 magic = LOV_MAGIC;
 373                 stripe_count = lov_get_stripecnt(lov, magic, 0);
 374         }
 375
 376         /* If we aren't passed an lsmp struct, we just want the size */
 377         if (!lsmp) {
 378                 /* XXX LOV STACKING call into osc for sizes */
 379                 LBUG();
 380                 RETURN(lov_stripe_md_size(stripe_count));
 381         }
 382         /* If we are passed an allocated struct but nothing to unpack, free */
 383         if (*lsmp && !lmm) {
 384                 lov_free_memmd(lsmp);
 385                 RETURN(0);
 386         }
 387
 388         lsm_size = lov_alloc_memmd(lsmp, stripe_count, LOV_PATTERN_RAID0,
 389                                    magic);
 390         if (lsm_size < 0)
 391                 RETURN(lsm_size);
 392
 393         /* If we are passed a pointer but nothing to unpack, we only alloc */
 394         if (!lmm)
 395                 RETURN(lsm_size);
 396
 397         LASSERT(lsm_op_find(magic) != NULL);
 398         rc = lsm_op_find(magic)->lsm_unpackmd(lov, *lsmp, lmm);
 399         if (rc) {
 400                 lov_free_memmd(lsmp);
 401                 RETURN(rc);
 402         }
 403
 404         RETURN(lsm_size);
 405 }
 406
 407 static int __lov_setstripe(struct obd_export *exp, int max_lmm_size,
 408                            struct lov_stripe_md **lsmp,
 409                            struct lov_user_md *lump)
 410 {
 411         struct obd_device *obd = class_exp2obd(exp);
 412         struct lov_obd *lov = &obd->u.lov;
 413         char buffer[sizeof(struct lov_user_md_v3)];
 414         struct lov_user_md_v3 *lumv3 = (struct lov_user_md_v3 *)&buffer[0];
 415         struct lov_user_md_v1 *lumv1 = (struct lov_user_md_v1 *)&buffer[0];
 416         int lmm_magic;
 417         __u16 stripe_count;
 418         int rc;
 419         int cplen = 0;
 420         ENTRY;
 421
 422         rc = lov_lum_swab_if_needed(lumv3, &lmm_magic, lump);
 423         if (rc)
 424                 RETURN(rc);
 425
 426         /* in the rest of the tests, as *lumv1 and lumv3 have the same
 427          * fields, we use lumv1 to avoid code duplication */
 428
 429         if (lumv1->lmm_pattern == 0) {
 430                 lumv1->lmm_pattern = lov->desc.ld_pattern ?
 431                         lov->desc.ld_pattern : LOV_PATTERN_RAID0;
 432         }
 433
 434         if (lumv1->lmm_pattern != LOV_PATTERN_RAID0) {
 435                 CDEBUG(D_IOCTL, "bad userland stripe pattern: %#x\n",
 436                        lumv1->lmm_pattern);
 437                 RETURN(-EINVAL);
 438         }
 439
 440         /* 64kB is the largest common page size we see (ia64), and matches the
 441          * check in lfs */
 442         if (lumv1->lmm_stripe_size & (LOV_MIN_STRIPE_SIZE - 1)) {
 443                 CDEBUG(D_IOCTL, "stripe size %u not multiple of %u, fixing\n",
 444                        lumv1->lmm_stripe_size, LOV_MIN_STRIPE_SIZE);
 445                 lumv1->lmm_stripe_size = LOV_MIN_STRIPE_SIZE;
 446         }
 447
 448         if ((lumv1->lmm_stripe_offset >= lov->desc.ld_tgt_count) &&
 449             (lumv1->lmm_stripe_offset !=
 450              (typeof(lumv1->lmm_stripe_offset))(-1))) {
 451                 CDEBUG(D_IOCTL, "stripe offset %u > number of OSTs %u\n",
 452                        lumv1->lmm_stripe_offset, lov->desc.ld_tgt_count);
 453                 RETURN(-EINVAL);
 454         }
 455         stripe_count = lov_get_stripecnt(lov, lmm_magic,
 456                                          lumv1->lmm_stripe_count);
 457
 458         if (max_lmm_size) {
 459                 int max_stripes = (max_lmm_size -
 460                                    lov_mds_md_size(0, lmm_magic)) /
 461                                    sizeof(struct lov_ost_data_v1);
 462                 if (unlikely(max_stripes < stripe_count)) {
 463                         CDEBUG(D_IOCTL, "stripe count reset from %d to %d\n",
 464                                stripe_count, max_stripes);
 465                         stripe_count = max_stripes;
 466                 }
 467         }
 468
 469         if (lmm_magic == LOV_USER_MAGIC_V3) {
 470                 struct pool_desc *pool;
 471
 472                 /* In the function below, .hs_keycmp resolves to
 473                  * pool_hashkey_keycmp() */
 474                 /* coverity[overrun-buffer-val] */
 475                 pool = lov_find_pool(lov, lumv3->lmm_pool_name);
 476                 if (pool != NULL) {
 477                         if (lumv3->lmm_stripe_offset !=
 478                             (typeof(lumv3->lmm_stripe_offset))(-1)) {
 479                                 rc = lov_check_index_in_pool(
 480                                         lumv3->lmm_stripe_offset, pool);
 481                                 if (rc < 0) {
 482                                         lov_pool_putref(pool);
 483                                         RETURN(-EINVAL);
 484                                 }
 485                         }
 486
 487                         if (stripe_count > pool_tgt_count(pool))
 488                                 stripe_count = pool_tgt_count(pool);
 489
 490                         lov_pool_putref(pool);
 491                 }
 492         }
 493
 494         rc = lov_alloc_memmd(lsmp, stripe_count, lumv1->lmm_pattern, lmm_magic);
 495
 496         if (rc >= 0) {
 497                 (*lsmp)->lsm_oinfo[0]->loi_ost_idx = lumv1->lmm_stripe_offset;
 498                 (*lsmp)->lsm_stripe_size = lumv1->lmm_stripe_size;
 499                 if (lmm_magic == LOV_USER_MAGIC_V3) {
 500                         cplen = strlcpy((*lsmp)->lsm_pool_name,
 501                                         lumv3->lmm_pool_name,
 502                                         sizeof((*lsmp)->lsm_pool_name));
 503                         if (cplen >= sizeof((*lsmp)->lsm_pool_name))
 504                                 rc = -E2BIG;
 505                 }
 506                 rc = 0;
 507         }
 508
 509         RETURN(rc);
 510 }
 511
 512 /* Configure object striping information on a new file.
 513  *
 514  * @lmmu is a pointer to a user struct with one or more of the fields set to
 515  * indicate the application preference: lmm_stripe_count, lmm_stripe_size,
 516  * lmm_stripe_offset, and lmm_stripe_pattern.  lmm_magic must be LOV_MAGIC.
 517  * @lsmp is a pointer to an in-core stripe MD that needs to be filled in.
 518  */
 519 int lov_setstripe(struct obd_export *exp, int max_lmm_size,
 520                   struct lov_stripe_md **lsmp, struct lov_user_md *lump)
 521 {
 522         int rc;
 523         mm_segment_t seg;
 524
 525         seg = get_fs();
 526         set_fs(KERNEL_DS);
 527
 528         rc = __lov_setstripe(exp, max_lmm_size, lsmp, lump);
 529         set_fs(seg);
 530         RETURN(rc);
 531 }
 532
 533 int lov_setea(struct obd_export *exp, struct lov_stripe_md **lsmp,
 534               struct lov_user_md *lump)
 535 {
 536         int i;
 537         int rc;
 538         struct obd_export *oexp;
 539         struct lov_obd *lov = &exp->exp_obd->u.lov;
 540         obd_id last_id = 0;
 541         struct lov_user_ost_data_v1 *lmm_objects;
 542
 543         ENTRY;
 544
 545         if (lump->lmm_magic == LOV_USER_MAGIC_V3)
 546                 lmm_objects = ((struct lov_user_md_v3 *)lump)->lmm_objects;
 547         else
 548                 lmm_objects = lump->lmm_objects;
 549
 550         for (i = 0; i < lump->lmm_stripe_count; i++) {
 551                 __u32 len = sizeof(last_id);
 552                 oexp = lov->lov_tgts[lmm_objects[i].l_ost_idx]->ltd_exp;
 553                 rc = obd_get_info(NULL, oexp, sizeof(KEY_LAST_ID), KEY_LAST_ID,
 554                                   &len, &last_id, NULL);
 555                 if (rc)
 556                         RETURN(rc);
 557                 if (lmm_objects[i].l_object_id > last_id) {
 558                         CERROR("Setting EA for object > than last id on "
 559                                "ost idx %d "LPD64" > "LPD64" \n",
 560                                lmm_objects[i].l_ost_idx,
 561                                lmm_objects[i].l_object_id, last_id);
 562                         RETURN(-EINVAL);
 563                 }
 564         }
 565
 566         rc = lov_setstripe(exp, 0, lsmp, lump);
 567         if (rc)
 568                 RETURN(rc);
 569
 570         for (i = 0; i < lump->lmm_stripe_count; i++) {
 571                 (*lsmp)->lsm_oinfo[i]->loi_ost_idx =
 572                         lmm_objects[i].l_ost_idx;
 573                 (*lsmp)->lsm_oinfo[i]->loi_id = lmm_objects[i].l_object_id;
 574                 (*lsmp)->lsm_oinfo[i]->loi_seq = lmm_objects[i].l_object_seq;
 575         }
 576         RETURN(0);
 577 }
 578
 579
 580 /* Retrieve object striping information.
 581  *
 582  * @lump is a pointer to an in-core struct with lmm_ost_count indicating
 583  * the maximum number of OST indices which will fit in the user buffer.
 584  * lmm_magic must be LOV_USER_MAGIC.
 585  */
 586 int lov_getstripe(struct obd_export *exp, struct lov_stripe_md *lsm,
 587                   struct lov_user_md *lump)
 588 {
 589         /*
 590          * XXX huge struct allocated on stack.
 591          */
 592         /* we use lov_user_md_v3 because it is larger than lov_user_md_v1 */
 593         struct lov_user_md_v3 lum;
 594         struct lov_mds_md *lmmk = NULL;
 595         int rc, lmm_size;
 596         int lum_size;
 597         mm_segment_t seg;
 598         ENTRY;
 599
 600         if (!lsm)
 601                 RETURN(-ENODATA);
 602
 603         /*
 604          * "Switch to kernel segment" to allow copying from kernel space by
 605          * copy_{to,from}_user().
 606          */
 607         seg = get_fs();
 608         set_fs(KERNEL_DS);
 609
 610         /* we only need the header part from user space to get lmm_magic and
 611          * lmm_stripe_count, (the header part is common to v1 and v3) */
 612         lum_size = sizeof(struct lov_user_md_v1);
 613         if (cfs_copy_from_user(&lum, lump, lum_size))
 614                 GOTO(out_set, rc = -EFAULT);
 615         else if ((lum.lmm_magic != LOV_USER_MAGIC) &&
 616                  (lum.lmm_magic != LOV_USER_MAGIC_V3))
 617                 GOTO(out_set, rc = -EINVAL);
 618
 619         if (lum.lmm_stripe_count &&
 620             (lum.lmm_stripe_count < lsm->lsm_stripe_count)) {
 621                 /* Return right size of stripe to user */
 622                 lum.lmm_stripe_count = lsm->lsm_stripe_count;
 623                 rc = cfs_copy_to_user(lump, &lum, lum_size);
 624                 GOTO(out_set, rc = -EOVERFLOW);
 625         }
 626         rc = lov_packmd(exp, &lmmk, lsm);
 627         if (rc < 0)
 628                 GOTO(out_set, rc);
 629         lmm_size = rc;
 630         rc = 0;
 631
 632         /* FIXME: Bug 1185 - copy fields properly when structs change */
 633         /* struct lov_user_md_v3 and struct lov_mds_md_v3 must be the same */
 634         CLASSERT(sizeof(lum) == sizeof(struct lov_mds_md_v3));
 635         CLASSERT(sizeof lum.lmm_objects[0] == sizeof lmmk->lmm_objects[0]);
 636
 637         if ((cpu_to_le32(LOV_MAGIC) != LOV_MAGIC) &&
 638             ((lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V1)) ||
 639             (lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V3)))) {
 640                 lustre_swab_lov_mds_md(lmmk);
 641                 lustre_swab_lov_user_md_objects(
 642                                 (struct lov_user_ost_data*)lmmk->lmm_objects,
 643                                 lmmk->lmm_stripe_count);
 644         }
 645         if (lum.lmm_magic == LOV_USER_MAGIC) {
 646                 /* User request for v1, we need skip lmm_pool_name */
 647                 if (lmmk->lmm_magic == LOV_MAGIC_V3) {
 648                         memmove((char*)(&lmmk->lmm_stripe_count) +
 649                                 sizeof(lmmk->lmm_stripe_count),
 650                                 ((struct lov_mds_md_v3*)lmmk)->lmm_objects,
 651                                 lmmk->lmm_stripe_count *
 652                                 sizeof(struct lov_ost_data_v1));
 653                         lmm_size -= LOV_MAXPOOLNAME;
 654                 }
 655         } else {
 656                 /* if v3 we just have to update the lum_size */
 657                 lum_size = sizeof(struct lov_user_md_v3);
 658         }
 659
 660         /* User wasn't expecting this many OST entries */
 661         if (lum.lmm_stripe_count == 0)
 662                 lmm_size = lum_size;
 663         else if (lum.lmm_stripe_count < lmmk->lmm_stripe_count)
 664                 GOTO(out_set, rc = -EOVERFLOW);
 665         /*
 666          * Have a difference between lov_mds_md & lov_user_md.
 667          * So we have to re-order the data before copy to user.
 668          */
 669         lum.lmm_stripe_count = lmmk->lmm_stripe_count;
 670         lum.u.lum_layout_gen = lmmk->lmm_layout_gen;
 671         ((struct lov_user_md*)lmmk)->u.lum_layout_gen = lum.u.lum_layout_gen;
 672         ((struct lov_user_md*)lmmk)->lmm_stripe_count = lum.lmm_stripe_count;
 673         if (cfs_copy_to_user(lump, lmmk, lmm_size))
 674                 rc = -EFAULT;
 675
 676         obd_free_diskmd(exp, &lmmk);
 677 out_set:
 678         set_fs(seg);
 679         RETURN(rc);
 680 }