lustre/mdt/mdt_restripe.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  * This file is part of Lustre, http://www.lustre.org/
  24  *
  25  * lustre/mdt/mdt_restriper.c
  26  *
  27  * Lustre directory restripe and auto-split
  28  */
  29
  30 #define DEBUG_SUBSYSTEM S_MDS
  31
  32 #include <linux/sched.h>
  33 #include <linux/kthread.h>
  34 #include "mdt_internal.h"
  35
  36 /* add directory into splitting list and wake up restripe thread */
  37 void mdt_auto_split_add(struct mdt_thread_info *info, struct mdt_object *o)
  38 {
  39         struct mdt_device *mdt = info->mti_mdt;
  40         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
  41
  42         spin_lock(&restriper->mdr_lock);
  43         if (mdt->mdt_enable_dir_auto_split && !o->mot_restriping) {
  44                 o->mot_restriping = 1;
  45                 mdt_object_get(NULL, o);
  46                 LASSERT(list_empty(&o->mot_restripe_linkage));
  47                 list_add_tail(&o->mot_restripe_linkage,
  48                               &restriper->mdr_auto_splitting);
  49
  50                 CDEBUG(D_INFO, "add "DFID" into auto split list.\n",
  51                        PFID(mdt_object_fid(o)));
  52         }
  53         spin_unlock(&restriper->mdr_lock);
  54
  55         wake_up_process(restriper->mdr_task);
  56 }
  57
  58 void mdt_restripe_migrate_add(struct mdt_thread_info *info,
  59                               struct mdt_object *o)
  60 {
  61         struct mdt_device *mdt = info->mti_mdt;
  62         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
  63
  64         spin_lock(&restriper->mdr_lock);
  65         if (!o->mot_restriping) {
  66                 o->mot_restriping = 1;
  67                 o->mot_restripe_offset = 0;
  68                 mdt_object_get(NULL, o);
  69                 LASSERT(list_empty(&o->mot_restripe_linkage));
  70                 list_add_tail(&o->mot_restripe_linkage,
  71                               &restriper->mdr_migrating);
  72
  73                 CDEBUG(D_INFO, "add "DFID" into migrate list.\n",
  74                        PFID(mdt_object_fid(o)));
  75         }
  76         spin_unlock(&restriper->mdr_lock);
  77
  78         wake_up_process(restriper->mdr_task);
  79 }
  80
  81 void mdt_restripe_update_add(struct mdt_thread_info *info,
  82                              struct mdt_object *o)
  83 {
  84         struct mdt_device *mdt = info->mti_mdt;
  85         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
  86
  87         spin_lock(&restriper->mdr_lock);
  88         if (!o->mot_restriping) {
  89                 /* update LMV */
  90                 o->mot_restriping = 1;
  91                 mdt_object_get(NULL, o);
  92                 if (list_empty(&restriper->mdr_updating))
  93                         restriper->mdr_update_time = ktime_get_real_seconds();
  94                 LASSERT(list_empty(&o->mot_restripe_linkage));
  95                 list_add_tail(&o->mot_restripe_linkage,
  96                               &restriper->mdr_updating);
  97
  98                 CDEBUG(D_INFO, "add "DFID" into update list.\n",
  99                        PFID(mdt_object_fid(o)));
 100         }
 101         spin_unlock(&restriper->mdr_lock);
 102
 103         wake_up_process(restriper->mdr_task);
 104 }
 105
 106 static inline int mdt_fid_alloc(const struct lu_env *env,
 107                                 struct mdt_device *mdt,
 108                                 struct lu_fid *fid,
 109                                 struct mdt_object *parent,
 110                                 const struct lu_name *name)
 111 {
 112         struct lu_device *next = &mdt->mdt_child->md_lu_dev;
 113         struct lu_object *o = lu_object_next(&parent->mot_obj);
 114
 115         return next->ld_ops->ldo_fid_alloc(env, next, fid, o, name);
 116 }
 117
 118 static void mdt_auto_split_prep(struct mdt_thread_info *info,
 119                                 struct md_op_spec *spec,
 120                                 struct md_attr *ma,
 121                                 u32 lum_stripe_count)
 122 {
 123         struct lu_attr *attr = &ma->ma_attr;
 124         struct lmv_user_md_v1 *lum;
 125
 126         attr->la_ctime = attr->la_mtime = ktime_get_real_seconds();
 127         attr->la_valid = LA_CTIME | LA_MTIME;
 128
 129         lum = &info->mti_mdt->mdt_restriper.mdr_lmv.lmv_user_md;
 130         lum->lum_magic = cpu_to_le32(LMV_USER_MAGIC);
 131         lum->lum_stripe_count = cpu_to_le32(lum_stripe_count);
 132         lum->lum_stripe_offset = cpu_to_le32(LMV_OFFSET_DEFAULT);
 133         lum->lum_hash_type = 0;
 134
 135         spec->u.sp_ea.eadatalen = sizeof(*lum);
 136         spec->u.sp_ea.eadata = lum;
 137         spec->sp_cr_flags = MDS_OPEN_HAS_EA;
 138         spec->no_create = 0;
 139         spec->sp_migrate_close = 0;
 140 }
 141
 142 /* restripe directory: split or merge stripes */
 143 int mdt_restripe_internal(struct mdt_thread_info *info,
 144                           struct mdt_object *parent,
 145                           struct mdt_object *child,
 146                           const struct lu_name *lname,
 147                           struct lu_fid *tfid,
 148                           struct md_op_spec *spec,
 149                           struct md_attr *ma)
 150 {
 151         const struct lu_env *env = info->mti_env;
 152         struct mdt_device *mdt = info->mti_mdt;
 153         struct lmv_user_md *lum = spec->u.sp_ea.eadata;
 154         struct lmv_mds_md_v1 *lmv;
 155         u32 lmv_stripe_count = 0;
 156         int rc;
 157
 158         ENTRY;
 159
 160         rc = mdt_stripe_get(info, child, ma, XATTR_NAME_LMV);
 161         if (rc)
 162                 RETURN(rc);
 163
 164         if (ma->ma_valid & MA_LMV) {
 165                 lmv = &ma->ma_lmv->lmv_md_v1;
 166                 if (!lmv_is_sane(lmv))
 167                         RETURN(-EBADF);
 168
 169                 /* don't allow restripe if dir layout is changing */
 170                 if (lmv_is_layout_changing(lmv))
 171                         RETURN(-EBUSY);
 172
 173                 /* check whether stripe count and hash unchanged */
 174                 if (lum->lum_stripe_count == lmv->lmv_stripe_count &&
 175                     lum->lum_hash_type == lmv->lmv_hash_type)
 176                         RETURN(-EALREADY);
 177
 178                 lmv_stripe_count = le32_to_cpu(lmv->lmv_stripe_count);
 179         } else if (le32_to_cpu(lum->lum_stripe_count) < 2) {
 180                 /* stripe count unchanged for plain directory */
 181                 RETURN(-EALREADY);
 182         }
 183
 184         if (le32_to_cpu(lum->lum_stripe_count) > lmv_stripe_count) {
 185                 /* split */
 186                 struct md_layout_change *mlc = &info->mti_mlc;
 187                 struct mdt_object *tobj = NULL;
 188                 s64 mtime = ma->ma_attr.la_mtime;
 189
 190                 ma->ma_need = MA_INODE;
 191                 ma->ma_valid = 0;
 192                 rc = mdt_attr_get_complex(info, child, ma);
 193                 if (rc)
 194                         RETURN(rc);
 195
 196                 if (!(ma->ma_valid & MA_INODE))
 197                         RETURN(-EBADF);
 198
 199                 /* mtime is from from client or set outside */
 200                 ma->ma_attr.la_mtime = mtime;
 201
 202                 if (!lmv_stripe_count) {
 203                         /* if child is plain directory, allocate @tobj as the
 204                          * master object, and make child the first stripe of
 205                          * @tobj.
 206                          */
 207                         tobj = mdt_object_new(env, mdt, tfid);
 208                         if (unlikely(IS_ERR(tobj)))
 209                                 RETURN(PTR_ERR(tobj));
 210                 }
 211
 212                 mlc->mlc_opc = MD_LAYOUT_SPLIT;
 213                 mlc->mlc_parent = mdt_object_child(parent);
 214                 mlc->mlc_target = tobj ? mdt_object_child(tobj) : NULL;
 215                 mlc->mlc_attr = &ma->ma_attr;
 216                 mlc->mlc_name = lname;
 217                 mlc->mlc_spec = spec;
 218                 rc = mo_layout_change(env, mdt_object_child(child), mlc);
 219                 if (!rc) {
 220                         /* FID and attr need to be replied to client for manual
 221                          * restripe.
 222                          */
 223                         ma->ma_need = MA_INODE;
 224                         ma->ma_valid = 0;
 225                         rc = mdt_attr_get_complex(info,
 226                                         lmv_stripe_count ? child : tobj, ma);
 227                 }
 228                 if (tobj)
 229                         mdt_object_put(env, tobj);
 230                 else
 231                         *tfid = *mdt_object_fid(child);
 232         } else {
 233                 /* merge only needs to override LMV */
 234                 struct lu_buf *buf = &info->mti_buf;
 235                 __u32 version;
 236
 237                 LASSERT(ma->ma_valid & MA_LMV);
 238                 lmv = &ma->ma_lmv->lmv_md_v1;
 239                 version = cpu_to_le32(lmv->lmv_layout_version);
 240
 241                 /* adjust 0 to 1 */
 242                 if (lum->lum_stripe_count == 0)
 243                         lum->lum_stripe_count = cpu_to_le32(1);
 244
 245                 lmv->lmv_hash_type |= cpu_to_le32(LMV_HASH_FLAG_MERGE |
 246                                                   LMV_HASH_FLAG_MIGRATION);
 247                 lmv->lmv_merge_offset = lum->lum_stripe_count;
 248                 lmv->lmv_merge_hash = lum->lum_hash_type;
 249                 lmv->lmv_layout_version = cpu_to_le32(++version);
 250
 251                 buf->lb_buf = lmv;
 252                 buf->lb_len = sizeof(*lmv);
 253                 rc = mo_xattr_set(env, mdt_object_child(child), buf,
 254                                   XATTR_NAME_LMV, LU_XATTR_REPLACE);
 255                 if (rc)
 256                         RETURN(rc);
 257
 258                 *tfid = *mdt_object_fid(child);
 259                 ma->ma_need = MA_INODE;
 260                 ma->ma_valid = 0;
 261                 rc = mdt_attr_get_complex(info, child, ma);
 262         }
 263
 264         RETURN(rc);
 265 }
 266
 267 static int mdt_auto_split(struct mdt_thread_info *info)
 268 {
 269         const struct lu_env *env = info->mti_env;
 270         struct mdt_device *mdt = info->mti_mdt;
 271         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 272         struct md_attr *ma = &info->mti_attr;
 273         struct md_op_spec *spec = &info->mti_spec;
 274         struct lu_name *lname = &info->mti_name;
 275         struct lu_fid *fid = &info->mti_tmp_fid2;
 276         struct mdt_object *parent = NULL;
 277         struct mdt_object *child = NULL;
 278         struct mdt_object *stripe = NULL;
 279         struct ldlm_enqueue_info *einfo = &info->mti_einfo[0];
 280         struct mdt_lock_handle *lhp;
 281         struct mdt_lock_handle *lhc;
 282         u32 lmv_stripe_count = 0;
 283         u32 lum_stripe_count = 0;
 284         int rc;
 285
 286         ENTRY;
 287
 288         if (!atomic_read(&mdt->mdt_mds_mds_conns))
 289                 RETURN(-EINVAL);
 290
 291         spin_lock(&restriper->mdr_lock);
 292         if (!list_empty(&restriper->mdr_auto_splitting)) {
 293                 child = list_entry(restriper->mdr_auto_splitting.next,
 294                                    typeof(*child), mot_restripe_linkage);
 295                 list_del_init(&child->mot_restripe_linkage);
 296         }
 297         spin_unlock(&restriper->mdr_lock);
 298
 299         if (!child)
 300                 RETURN(0);
 301
 302         LASSERT(child->mot_restriping);
 303
 304         rc = mdt_stripe_get(info, child, ma, XATTR_NAME_LMV);
 305         if (rc)
 306                 GOTO(out, rc);
 307
 308         if (ma->ma_valid & MA_LMV) {
 309                 /* stripe dirent exceeds threshold, find its master object */
 310                 struct lmv_mds_md_v1 *lmv = &ma->ma_lmv->lmv_md_v1;
 311
 312                 /* auto-split won't be done on striped directory master object
 313                  * directly, because it's triggered when dirent count exceeds
 314                  * threshold, however dirent count of master object is its
 315                  * stripe count.
 316                  */
 317                 if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_STRIPE)
 318                         GOTO(out, rc = -EINVAL);
 319
 320                 /* race with migrate? */
 321                 if (lmv_hash_is_migrating(cpu_to_le32(lmv->lmv_hash_type)))
 322                         GOTO(out, rc = -EBUSY);
 323
 324                 lmv_stripe_count = le32_to_cpu(lmv->lmv_stripe_count);
 325
 326                 /* save stripe to clear 'restriping' flag in the end to avoid
 327                  * trigger auto-split multiple times.
 328                  */
 329                 stripe = child;
 330                 child = NULL;
 331
 332                 /* get master object FID from linkea */
 333                 rc = mdt_attr_get_pfid(info, stripe, &ma->ma_pfid);
 334                 if (rc)
 335                         GOTO(out, rc);
 336
 337                 child = mdt_object_find(env, mdt, &ma->ma_pfid);
 338                 if (IS_ERR(child))
 339                         GOTO(out, rc = PTR_ERR(child));
 340
 341                 spin_lock(&restriper->mdr_lock);
 342                 if (child->mot_restriping) {
 343                         /* race? */
 344                         spin_unlock(&restriper->mdr_lock);
 345                         GOTO(out, rc = -EBUSY);
 346                 }
 347                 child->mot_restriping = 1;
 348                 spin_unlock(&restriper->mdr_lock);
 349
 350                 /* skip if master object is remote, let the first stripe
 351                  * to start splitting because dir split needs to be done
 352                  * on where master object is.
 353                  */
 354                 if (mdt_object_remote(child))
 355                         GOTO(restriping_clear, rc = -EREMOTE);
 356         }
 357
 358         /* striped directory split adds mdr_auto_split_delta stripes */
 359         lum_stripe_count = min_t(unsigned int,
 360                                 lmv_stripe_count +
 361                                         mdt->mdt_restriper.mdr_dir_split_delta,
 362                                 atomic_read(&mdt->mdt_mds_mds_conns) + 1);
 363         if (lmv_stripe_count >= lum_stripe_count)
 364                 GOTO(restriping_clear, rc = -EALREADY);
 365
 366         /* get dir name and parent FID */
 367         rc = mdt_attr_get_pfid_name(info, child, fid, lname);
 368         if (rc)
 369                 GOTO(restriping_clear, rc);
 370
 371         /* copy name out because mti_linkea will be used later, and name should
 372          * end with '\0'
 373          */
 374         memcpy(info->mti_filename, lname->ln_name, lname->ln_namelen);
 375         info->mti_filename[lname->ln_namelen] = '\0';
 376         lname->ln_name = info->mti_filename;
 377         CDEBUG(D_INFO, "split "DFID"/"DNAME" to count %u (MDT count %d)\n",
 378                PFID(fid), PNAME(lname), lum_stripe_count,
 379                atomic_read(&mdt->mdt_mds_mds_conns) + 1);
 380
 381         parent = mdt_object_find(env, mdt, fid);
 382         if (IS_ERR(parent))
 383                 GOTO(restriping_clear, rc = PTR_ERR(parent));
 384
 385         rc = mdt_fid_alloc(env, mdt, fid, child, NULL);
 386         if (rc < 0)
 387                 GOTO(restriping_clear, rc);
 388
 389         lhp = &info->mti_lh[MDT_LH_PARENT];
 390         mdt_lock_pdo_init(lhp, LCK_PW, lname);
 391         rc = mdt_reint_object_lock(info, parent, lhp, MDS_INODELOCK_UPDATE,
 392                                    true);
 393         if (rc)
 394                 GOTO(restriping_clear, rc);
 395
 396         lhc = &info->mti_lh[MDT_LH_CHILD];
 397         mdt_lock_reg_init(lhc, LCK_EX);
 398         if (mdt_object_remote(parent)) {
 399                 /* enqueue object remote LOOKUP lock */
 400                 rc = mdt_remote_object_lock(info, parent, mdt_object_fid(child),
 401                                             &lhc->mlh_rreg_lh,
 402                                             lhc->mlh_rreg_mode,
 403                                             MDS_INODELOCK_LOOKUP, false);
 404                 if (rc != ELDLM_OK)
 405                         GOTO(unlock_parent, rc);
 406         }
 407
 408         rc = mdt_reint_striped_lock(info, child, lhc, MDS_INODELOCK_FULL, einfo,
 409                                     true);
 410         if (rc)
 411                 GOTO(unlock_child, rc);
 412
 413         mdt_auto_split_prep(info, spec, ma, lum_stripe_count);
 414
 415         rc = mdt_restripe_internal(info, parent, child, lname, fid, spec, ma);
 416         EXIT;
 417
 418 unlock_child:
 419         mdt_reint_striped_unlock(info, child, lhc, einfo, rc);
 420 unlock_parent:
 421         mdt_object_unlock(info, parent, lhp, rc);
 422 restriping_clear:
 423         child->mot_restriping = 0;
 424         LASSERT(list_empty(&child->mot_restripe_linkage));
 425 out:
 426         /* -EALREADY:   dir is split already.
 427          * -EBUSY:      dir is opened, or is splitting by others.
 428          * -EREMOTE:    dir is remote.
 429          */
 430         if (rc && rc != -EALREADY && rc != -EBUSY && rc != -EREMOTE)
 431                 CERROR("%s: split "DFID"/"DNAME" to count %u failed: rc = %d\n",
 432                        mdt_obd_name(mdt), PFID(mdt_object_fid(child)),
 433                        PNAME(lname), lum_stripe_count, rc);
 434
 435         if (!IS_ERR_OR_NULL(child))
 436                 mdt_object_put(env, child);
 437
 438         if (stripe) {
 439                 LASSERT(stripe->mot_restriping);
 440                 LASSERT(list_empty(&stripe->mot_restripe_linkage));
 441                 stripe->mot_restriping = 0;
 442                 /* lock may not be taken, don't cache stripe LMV */
 443                 mo_invalidate(env, mdt_object_child(stripe));
 444                 mdt_object_put(env, stripe);
 445         }
 446
 447         if (!IS_ERR_OR_NULL(parent))
 448                 mdt_object_put(env, parent);
 449
 450         return rc;
 451 }
 452
 453 /* sub-files under one stripe are migrated, clear MIGRATION flag in its LMV */
 454 static int mdt_restripe_migrate_finish(struct mdt_thread_info *info,
 455                                        struct mdt_object *stripe,
 456                                        struct lmv_mds_md_v1 *lmv)
 457 {
 458         struct mdt_device *mdt = info->mti_mdt;
 459         struct lu_buf buf;
 460         struct mdt_lock_handle *lh;
 461         int rc;
 462
 463         ENTRY;
 464
 465         LASSERT(le32_to_cpu(lmv->lmv_magic) == LMV_MAGIC_STRIPE);
 466         LASSERT(lmv_is_restriping(lmv));
 467
 468         lmv->lmv_hash_type &= ~cpu_to_le32(LMV_HASH_FLAG_MIGRATION);
 469         buf.lb_buf = lmv;
 470         buf.lb_len = sizeof(*lmv);
 471
 472         lh = &info->mti_lh[MDT_LH_PARENT];
 473         mdt_lock_reg_init(lh, LCK_EX);
 474         rc = mdt_reint_object_lock(info, stripe, lh, MDS_INODELOCK_XATTR,
 475                                    false);
 476         if (!rc)
 477                 rc = mo_xattr_set(info->mti_env, mdt_object_child(stripe), &buf,
 478                                   XATTR_NAME_LMV, LU_XATTR_REPLACE);
 479         mdt_object_unlock(info, stripe, lh, rc);
 480         if (rc)
 481                 CERROR("%s: update "DFID" LMV failed: rc = %d\n",
 482                        mdt_obd_name(mdt), PFID(mdt_object_fid(stripe)), rc);
 483
 484         LASSERT(!list_empty(&stripe->mot_restripe_linkage));
 485         LASSERT(stripe->mot_restriping);
 486
 487         spin_lock(&mdt->mdt_lock);
 488         stripe->mot_restriping = 0;
 489         list_del_init(&stripe->mot_restripe_linkage);
 490         spin_unlock(&mdt->mdt_lock);
 491
 492         mdt_object_put(info->mti_env, stripe);
 493
 494         RETURN(rc);
 495 }
 496
 497 static void mdt_restripe_migrate_prep(struct mdt_thread_info *info,
 498                                       const struct lu_fid *fid1,
 499                                       const struct lu_fid *fid2,
 500                                       const struct lu_name *lname,
 501                                       __u16 type,
 502                                       const struct lmv_mds_md_v1 *lmv)
 503 {
 504         struct lu_attr *attr = &info->mti_attr.ma_attr;
 505         struct mdt_reint_record *rr = &info->mti_rr;
 506         struct md_op_spec *spec = &info->mti_spec;
 507         struct lmv_user_md_v1 *lum;
 508
 509         attr->la_ctime = attr->la_mtime = ktime_get_real_seconds();
 510         attr->la_valid = LA_CTIME | LA_MTIME;
 511
 512         rr->rr_fid1 = fid1;
 513         rr->rr_fid2 = fid2;
 514         rr->rr_name = *lname;
 515
 516         lum = &info->mti_mdt->mdt_restriper.mdr_lmv.lmv_user_md;
 517         lum->lum_magic = cpu_to_le32(LMV_USER_MAGIC);
 518         lum->lum_stripe_offset = cpu_to_le32(LMV_OFFSET_DEFAULT);
 519         if (lmv_is_splitting(lmv)) {
 520                 lum->lum_stripe_count = lmv->lmv_stripe_count;
 521                 lum->lum_hash_type =
 522                         lmv->lmv_hash_type & le32_to_cpu(LMV_HASH_TYPE_MASK);
 523         } else if (lmv_is_merging(lmv)) {
 524                 lum->lum_stripe_count = lmv->lmv_merge_offset;
 525                 lum->lum_hash_type = lmv->lmv_merge_hash;
 526         }
 527
 528         spec->u.sp_ea.eadatalen = sizeof(*lum);
 529         spec->u.sp_ea.eadata = lum;
 530         spec->sp_cr_flags = MDS_OPEN_HAS_EA;
 531         spec->no_create = 0;
 532         spec->sp_migrate_close = 0;
 533         /* if 'nsonly' is set, don't migrate inode */
 534         if (S_ISDIR(type))
 535                 spec->sp_migrate_nsonly = 1;
 536         else
 537                 spec->sp_migrate_nsonly =
 538                         info->mti_mdt->mdt_dir_restripe_nsonly;
 539 }
 540
 541 /* migrate sub-file from @mdr_restripe_offset */
 542 static int mdt_restripe_migrate(struct mdt_thread_info *info)
 543 {
 544         const struct lu_env *env = info->mti_env;
 545         struct mdt_device *mdt = info->mti_mdt;
 546         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 547         struct mdt_object *stripe = NULL;
 548         struct mdt_object *master = NULL;
 549         struct md_attr *ma = &info->mti_attr;
 550         struct lmv_mds_md_v1 *lmv;
 551         struct lu_name *lname = &info->mti_name;
 552         struct lu_rdpg *rdpg = &info->mti_u.rdpg.mti_rdpg;
 553         struct lu_fid fid1;
 554         struct lu_fid fid2;
 555         struct lu_dirpage *dp;
 556         struct lu_dirent *ent;
 557         const char *name = NULL;
 558         int namelen = 0;
 559         __u16 type;
 560         int idx = 0;
 561         int len;
 562         int rc;
 563
 564         ENTRY;
 565
 566         if (list_empty(&restriper->mdr_migrating))
 567                 RETURN(0);
 568
 569         stripe = list_entry(restriper->mdr_migrating.next, typeof(*stripe),
 570                             mot_restripe_linkage);
 571
 572         /* get master object FID and stripe name */
 573         rc = mdt_attr_get_pfid_name(info, stripe, &fid1, lname);
 574         if (rc)
 575                 GOTO(out, rc);
 576
 577         snprintf(info->mti_filename, sizeof(info->mti_filename), DFID,
 578                  PFID(mdt_object_fid(stripe)));
 579         len = strlen(info->mti_filename) + 1;
 580         if (len >= lname->ln_namelen)
 581                 GOTO(out, rc = -EBADF);
 582
 583         while (len < lname->ln_namelen) {
 584                 if (!isdigit(lname->ln_name[len]))
 585                         GOTO(out, rc = -EBADF);
 586
 587                 idx = idx * 10 + lname->ln_name[len++] - '0';
 588         };
 589
 590         /* check whether stripe is newly created in split */
 591         rc = mdt_stripe_get(info, stripe, ma, XATTR_NAME_LMV);
 592         if (rc)
 593                 GOTO(out, rc);
 594
 595         if (!(ma->ma_valid & MA_LMV))
 596                 GOTO(out, rc = -ENODATA);
 597
 598         lmv = &ma->ma_lmv->lmv_md_v1;
 599         if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_STRIPE)
 600                 GOTO(out, rc = -EBADF);
 601
 602         if (!lmv_is_restriping(lmv))
 603                 GOTO(out, rc = -EINVAL);
 604
 605         if ((lmv_is_splitting(lmv) &&
 606              idx >= le32_to_cpu(lmv->lmv_split_offset)) ||
 607             (lmv_is_merging(lmv) &&
 608              le32_to_cpu(lmv->lmv_hash_type) == LMV_HASH_TYPE_CRUSH &&
 609              idx < le32_to_cpu(lmv->lmv_merge_offset))) {
 610                 /* new stripes doesn't need to migrate sub files in dir
 611                  * split, neither for target stripes in dir merge if hash type
 612                  * is CRUSH.
 613                  */
 614                 rc = mdt_restripe_migrate_finish(info, stripe, lmv);
 615                 RETURN(rc);
 616         }
 617
 618         /* get sub file name @mot_restripe_offset.
 619          * TODO: read one dirent instead of whole page.
 620          */
 621         rdpg->rp_hash = stripe->mot_restripe_offset;
 622         rdpg->rp_count = PAGE_SIZE;
 623         rdpg->rp_npages = 1;
 624         rdpg->rp_attrs = LUDA_64BITHASH | LUDA_FID | LUDA_TYPE;
 625         rdpg->rp_pages = &restriper->mdr_page;
 626         rc = mo_readpage(env, mdt_object_child(stripe), rdpg);
 627         if (rc < 0)
 628                 GOTO(out, rc);
 629
 630         dp = page_address(restriper->mdr_page);
 631         for (ent = lu_dirent_start(dp); ent; ent = lu_dirent_next(ent)) {
 632                 LASSERT(le64_to_cpu(ent->lde_hash) >= rdpg->rp_hash);
 633
 634                 if (unlikely(!(le32_to_cpu(ent->lde_attrs) & LUDA_TYPE)))
 635                         GOTO(out, rc = -EINVAL);
 636
 637                 namelen = le16_to_cpu(ent->lde_namelen);
 638                 if (!namelen)
 639                         continue;
 640
 641                 if (name_is_dot_or_dotdot(ent->lde_name, namelen))
 642                         continue;
 643
 644                 name = ent->lde_name;
 645                 type = lu_dirent_type_get(ent);
 646                 break;
 647         }
 648
 649         if (!name) {
 650                 if (le64_to_cpu(dp->ldp_hash_end) == MDS_DIR_END_OFF) {
 651                         rc = mdt_restripe_migrate_finish(info, stripe, lmv);
 652                         RETURN(rc);
 653                 }
 654
 655                 GOTO(out, rc = -EBADF);
 656         }
 657
 658         /* copy name out because it should end with '\0' */
 659         memcpy(info->mti_filename, name, namelen);
 660         info->mti_filename[namelen] = '\0';
 661         lname->ln_name = info->mti_filename;
 662         lname->ln_namelen = namelen;
 663
 664         CDEBUG(D_INFO, "migrate "DFID"/"DNAME" type %ho\n",
 665                PFID(&fid1), PNAME(lname), type);
 666
 667         master = mdt_object_find(env, mdt, &fid1);
 668         if (IS_ERR(master))
 669                 GOTO(out, rc = PTR_ERR(master));
 670
 671         rc = mdt_fid_alloc(env, mdt, &fid2, master, lname);
 672         mdt_object_put(env, master);
 673         if (rc < 0)
 674                 GOTO(out, rc);
 675
 676         mdt_restripe_migrate_prep(info, &fid1, &fid2, lname, type, lmv);
 677
 678         rc = mdt_reint_migrate(info, NULL);
 679         /* mti_big_buf is allocated in XATTR migration */
 680         if (unlikely(info->mti_big_buf.lb_buf))
 681                 lu_buf_free(&info->mti_big_buf);
 682         if (rc == -EALREADY)
 683                 rc = 0;
 684         if (rc)
 685                 GOTO(out, rc);
 686
 687         LASSERT(ent);
 688         do {
 689                 ent = lu_dirent_next(ent);
 690                 if (!ent)
 691                         break;
 692
 693                 namelen = le16_to_cpu(ent->lde_namelen);
 694         } while (namelen == 0); /* Skip dummy record */
 695
 696         if (ent)
 697                 stripe->mot_restripe_offset = le64_to_cpu(ent->lde_hash);
 698         else
 699                 stripe->mot_restripe_offset = le64_to_cpu(dp->ldp_hash_end);
 700
 701         EXIT;
 702 out:
 703         if (rc) {
 704                 /* -EBUSY: file is opened by others */
 705                 if (rc != -EBUSY)
 706                         CERROR("%s: migrate "DFID"/"DNAME" failed: rc = %d\n",
 707                                mdt_obd_name(mdt), PFID(&fid1), PNAME(lname),
 708                                rc);
 709
 710                 spin_lock(&mdt->mdt_lock);
 711                 stripe->mot_restriping = 0;
 712                 list_del_init(&stripe->mot_restripe_linkage);
 713                 spin_unlock(&mdt->mdt_lock);
 714
 715                 mdt_object_put(env, stripe);
 716         }
 717
 718         return rc;
 719 }
 720
 721 static inline bool mdt_restripe_update_pending(struct mdt_thread_info *info)
 722 {
 723         struct mdt_device *mdt = info->mti_mdt;
 724
 725         if (list_empty(&mdt->mdt_restriper.mdr_updating))
 726                 return false;
 727
 728         return mdt->mdt_restriper.mdr_update_time < ktime_get_real_seconds();
 729 }
 730
 731 static void mdt_restripe_layout_update_prep(struct mdt_thread_info *info,
 732                                             const struct lu_fid *fid,
 733                                             const struct lmv_mds_md_v1 *lmv)
 734 {
 735         struct lu_attr *attr = &info->mti_attr.ma_attr;
 736         struct mdt_reint_record *rr = &info->mti_rr;
 737         struct lmv_user_md_v1 *lum;
 738
 739         attr->la_ctime = attr->la_mtime = ktime_get_real_seconds();
 740         attr->la_valid = LA_CTIME | LA_MTIME;
 741
 742         strncpy(info->mti_filename, XATTR_NAME_LMV,
 743                 sizeof(info->mti_filename));
 744
 745         lum = &info->mti_mdt->mdt_restriper.mdr_lmv.lmv_user_md;
 746         lum->lum_magic = cpu_to_le32(LMV_USER_MAGIC);
 747         lum->lum_stripe_offset = cpu_to_le32(LMV_OFFSET_DEFAULT);
 748         if (lmv_is_splitting(lmv)) {
 749                 lum->lum_stripe_count = lmv->lmv_stripe_count;
 750                 lum->lum_hash_type =
 751                         lmv->lmv_hash_type & le32_to_cpu(LMV_HASH_TYPE_MASK);
 752         } else if (lmv_is_merging(lmv)) {
 753                 lum->lum_stripe_count = lmv->lmv_merge_offset;
 754                 lum->lum_hash_type = lmv->lmv_merge_hash;
 755         }
 756
 757         rr->rr_opcode = REINT_SETXATTR;
 758         rr->rr_fid1 = fid;
 759         rr->rr_name.ln_name = info->mti_filename;
 760         rr->rr_name.ln_namelen = strlen(info->mti_filename);
 761         rr->rr_eadata = lum;
 762         rr->rr_eadatalen = sizeof(*lum);
 763 }
 764
 765 static int mdt_restripe_layout_update(struct mdt_thread_info *info)
 766 {
 767         const struct lu_env *env = info->mti_env;
 768         struct mdt_device *mdt = info->mti_mdt;
 769         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 770         struct md_attr *ma = &info->mti_attr;
 771         struct lu_fid *fid = &info->mti_tmp_fid1;
 772         struct mdt_object *master;
 773         struct mdt_object *stripe;
 774         struct lmv_mds_md_v1 *lmv;
 775         int i;
 776         int rc;
 777
 778         ENTRY;
 779
 780         if (list_empty(&restriper->mdr_updating))
 781                 RETURN(0);
 782
 783         master = list_entry(restriper->mdr_updating.next, typeof(*master),
 784                             mot_restripe_linkage);
 785
 786         rc = mdt_stripe_get(info, master, ma, XATTR_NAME_LMV);
 787         if (rc)
 788                 GOTO(out, rc);
 789
 790         if (!(ma->ma_valid & MA_LMV))
 791                 GOTO(out, rc = -ENODATA);
 792
 793         lmv = &ma->ma_lmv->lmv_md_v1;
 794         if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_V1)
 795                 GOTO(out, rc = -EBADF);
 796
 797         if (!lmv_is_restriping(lmv))
 798                 GOTO(out, rc = -EINVAL);
 799
 800         /* use different buffer to store stripe LMV */
 801         ma->ma_lmv = &restriper->mdr_lmv;
 802         ma->ma_lmv_size = sizeof(restriper->mdr_lmv);
 803         for (i = 0; i < le32_to_cpu(lmv->lmv_stripe_count); i++) {
 804                 fid_le_to_cpu(fid, &lmv->lmv_stripe_fids[i]);
 805                 stripe = mdt_object_find(env, mdt, fid);
 806                 if (IS_ERR(stripe))
 807                         GOTO(out, rc = PTR_ERR(stripe));
 808
 809                 ma->ma_valid = 0;
 810                 rc = __mdt_stripe_get(info, stripe, ma, XATTR_NAME_LMV);
 811                 /* LMV is checked without lock, don't cache it */
 812                 mo_invalidate(env, mdt_object_child(stripe));
 813                 mdt_object_put(env, stripe);
 814                 if (rc)
 815                         GOTO(out, rc);
 816
 817                 if (!(ma->ma_valid & MA_LMV))
 818                         GOTO(out, rc = -ENODATA);
 819
 820                 /* check MIGRATION flag cleared on all stripes */
 821                 if (lmv_is_restriping(&ma->ma_lmv->lmv_md_v1))
 822                         GOTO(out, rc = -EINPROGRESS);
 823         }
 824
 825         mdt_restripe_layout_update_prep(info, mdt_object_fid(master), lmv);
 826
 827         rc = mdt_dir_layout_update(info);
 828         if (rc) {
 829                 CERROR("update "DFID" layout failed: rc = %d\n",
 830                        PFID(mdt_object_fid(master)), rc);
 831                 GOTO(out, rc);
 832         }
 833
 834 out:
 835         LASSERT(!list_empty(&master->mot_restripe_linkage));
 836         if (rc == -EINPROGRESS) {
 837                 restriper->mdr_update_time = ktime_get_real_seconds() + 5;
 838         } else {
 839                 spin_lock(&restriper->mdr_lock);
 840                 master->mot_restriping = 0;
 841                 list_del_init(&master->mot_restripe_linkage);
 842                 spin_unlock(&restriper->mdr_lock);
 843
 844                 mdt_object_put(env, master);
 845         }
 846
 847         return rc;
 848 }
 849
 850 static int mdt_restriper_main(void *arg)
 851 {
 852         struct mdt_thread_info *info = arg;
 853         struct mdt_device *mdt = info->mti_mdt;
 854         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 855
 856         ENTRY;
 857
 858         while (({set_current_state(TASK_IDLE);
 859                  !kthread_should_stop(); })) {
 860                 if (!list_empty(&restriper->mdr_auto_splitting)) {
 861                         __set_current_state(TASK_RUNNING);
 862                         mdt_auto_split(info);
 863                         cond_resched();
 864                 } else if (mdt_restripe_update_pending(info)) {
 865                         __set_current_state(TASK_RUNNING);
 866                         mdt_restripe_layout_update(info);
 867                         cond_resched();
 868                 } else if (!list_empty(&restriper->mdr_migrating)) {
 869                         __set_current_state(TASK_RUNNING);
 870                         mdt_restripe_migrate(info);
 871                         cond_resched();
 872                 } else {
 873                         schedule();
 874                 }
 875         }
 876         __set_current_state(TASK_RUNNING);
 877
 878         RETURN(0);
 879 }
 880
 881 int mdt_restriper_start(struct mdt_device *mdt)
 882 {
 883         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 884         kernel_cap_t kcap = cap_combine(CAP_FS_SET, CAP_NFSD_SET);
 885         struct task_struct *task;
 886         struct mdt_thread_info *info;
 887         struct lu_ucred *uc;
 888         int rc;
 889
 890         ENTRY;
 891
 892         spin_lock_init(&restriper->mdr_lock);
 893         INIT_LIST_HEAD(&restriper->mdr_auto_splitting);
 894         INIT_LIST_HEAD(&restriper->mdr_migrating);
 895         INIT_LIST_HEAD(&restriper->mdr_updating);
 896         restriper->mdr_dir_split_count = DIR_SPLIT_COUNT_DEFAULT;
 897         restriper->mdr_dir_split_delta = DIR_SPLIT_DELTA_DEFAULT;
 898
 899         restriper->mdr_page = alloc_page(GFP_KERNEL);
 900         if (!restriper->mdr_page)
 901                 RETURN(-ENOMEM);
 902
 903         rc = lu_env_init(&restriper->mdr_env, LCT_MD_THREAD);
 904         if (rc)
 905                 GOTO(out_page, rc);
 906
 907         rc = lu_context_init(&restriper->mdr_session, LCT_SERVER_SESSION);
 908         if (rc)
 909                 GOTO(out_env, rc);
 910
 911         lu_context_enter(&restriper->mdr_session);
 912         restriper->mdr_env.le_ses = &restriper->mdr_session;
 913
 914         info = lu_context_key_get(&restriper->mdr_env.le_ctx, &mdt_thread_key);
 915         info->mti_env = &restriper->mdr_env;
 916         info->mti_mdt = mdt;
 917         info->mti_pill = NULL;
 918         info->mti_dlm_req = NULL;
 919
 920         uc = mdt_ucred(info);
 921         uc->uc_valid = UCRED_OLD;
 922         uc->uc_o_uid = 0;
 923         uc->uc_o_gid = 0;
 924         uc->uc_o_fsuid = 0;
 925         uc->uc_o_fsgid = 0;
 926         uc->uc_uid = 0;
 927         uc->uc_gid = 0;
 928         uc->uc_fsuid = 0;
 929         uc->uc_fsgid = 0;
 930         uc->uc_suppgids[0] = -1;
 931         uc->uc_suppgids[1] = -1;
 932         uc->uc_cap = kcap.cap[0];
 933         uc->uc_umask = 0644;
 934         uc->uc_ginfo = NULL;
 935         uc->uc_identity = NULL;
 936
 937         task = kthread_create(mdt_restriper_main, info, "mdt_restriper_%03d",
 938                               mdt_seq_site(mdt)->ss_node_id);
 939         if (IS_ERR(task)) {
 940                 rc = PTR_ERR(task);
 941                 CERROR("%s: Can't start directory restripe thread: rc %d\n",
 942                        mdt_obd_name(mdt), rc);
 943                 GOTO(out_ses, rc);
 944         }
 945         restriper->mdr_task = task;
 946         wake_up_process(task);
 947
 948         RETURN(0);
 949
 950 out_ses:
 951         lu_context_exit(restriper->mdr_env.le_ses);
 952         lu_context_fini(restriper->mdr_env.le_ses);
 953 out_env:
 954         lu_env_fini(&restriper->mdr_env);
 955 out_page:
 956         __free_page(restriper->mdr_page);
 957
 958         return rc;
 959 }
 960
 961 void mdt_restriper_stop(struct mdt_device *mdt)
 962 {
 963         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 964         struct lu_env *env = &restriper->mdr_env;
 965         struct mdt_object *mo, *next;
 966
 967         if (!restriper->mdr_task)
 968                 return;
 969
 970         kthread_stop(restriper->mdr_task);
 971         restriper->mdr_task = NULL;
 972
 973         list_for_each_entry_safe(mo, next, &restriper->mdr_auto_splitting,
 974                                  mot_restripe_linkage) {
 975                 list_del_init(&mo->mot_restripe_linkage);
 976                 mdt_object_put(env, mo);
 977         }
 978
 979         list_for_each_entry_safe(mo, next, &restriper->mdr_migrating,
 980                                  mot_restripe_linkage) {
 981                 list_del_init(&mo->mot_restripe_linkage);
 982                 mdt_object_put(env, mo);
 983         }
 984
 985         list_for_each_entry_safe(mo, next, &restriper->mdr_updating,
 986                                  mot_restripe_linkage) {
 987                 list_del_init(&mo->mot_restripe_linkage);
 988                 mdt_object_put(env, mo);
 989         }
 990
 991         __free_page(restriper->mdr_page);
 992
 993         lu_context_exit(env->le_ses);
 994         lu_context_fini(env->le_ses);
 995         lu_env_fini(env);
 996 }