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_hash_type |= lum->lum_hash_type &
 248                                       cpu_to_le32(LMV_HASH_FLAG_FIXED);
 249                 lmv->lmv_merge_offset = lum->lum_stripe_count;
 250                 lmv->lmv_merge_hash = lum->lum_hash_type;
 251                 lmv->lmv_layout_version = cpu_to_le32(++version);
 252
 253                 buf->lb_buf = lmv;
 254                 buf->lb_len = sizeof(*lmv);
 255                 rc = mo_xattr_set(env, mdt_object_child(child), buf,
 256                                   XATTR_NAME_LMV, LU_XATTR_REPLACE);
 257                 if (rc)
 258                         RETURN(rc);
 259
 260                 *tfid = *mdt_object_fid(child);
 261                 ma->ma_need = MA_INODE;
 262                 ma->ma_valid = 0;
 263                 rc = mdt_attr_get_complex(info, child, ma);
 264         }
 265
 266         RETURN(rc);
 267 }
 268
 269 static int mdt_auto_split(struct mdt_thread_info *info)
 270 {
 271         const struct lu_env *env = info->mti_env;
 272         struct mdt_device *mdt = info->mti_mdt;
 273         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 274         struct md_attr *ma = &info->mti_attr;
 275         struct md_op_spec *spec = &info->mti_spec;
 276         struct lu_name *lname = &info->mti_name;
 277         struct lu_fid *fid = &info->mti_tmp_fid2;
 278         struct mdt_object *parent = NULL;
 279         struct mdt_object *child = NULL;
 280         struct mdt_object *stripe = NULL;
 281         struct ldlm_enqueue_info *einfo = &info->mti_einfo[0];
 282         struct mdt_lock_handle *lhp;
 283         struct mdt_lock_handle *lhc;
 284         u32 lmv_stripe_count = 0;
 285         u32 lum_stripe_count = 0;
 286         int rc;
 287
 288         ENTRY;
 289
 290         if (!atomic_read(&mdt->mdt_mds_mds_conns))
 291                 RETURN(-EINVAL);
 292
 293         spin_lock(&restriper->mdr_lock);
 294         if (!list_empty(&restriper->mdr_auto_splitting)) {
 295                 child = list_entry(restriper->mdr_auto_splitting.next,
 296                                    typeof(*child), mot_restripe_linkage);
 297                 list_del_init(&child->mot_restripe_linkage);
 298         }
 299         spin_unlock(&restriper->mdr_lock);
 300
 301         if (!child)
 302                 RETURN(0);
 303
 304         LASSERT(child->mot_restriping);
 305
 306         rc = mdt_stripe_get(info, child, ma, XATTR_NAME_LMV);
 307         if (rc)
 308                 GOTO(out, rc);
 309
 310         if (ma->ma_valid & MA_LMV) {
 311                 /* stripe dirent exceeds threshold, find its master object */
 312                 struct lmv_mds_md_v1 *lmv = &ma->ma_lmv->lmv_md_v1;
 313
 314                 /* auto-split won't be done on striped directory master object
 315                  * directly, because it's triggered when dirent count exceeds
 316                  * threshold, however dirent count of master object is its
 317                  * stripe count.
 318                  */
 319                 if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_STRIPE)
 320                         GOTO(out, rc = -EINVAL);
 321
 322                 /* race with migrate? */
 323                 if (lmv_hash_is_migrating(cpu_to_le32(lmv->lmv_hash_type)))
 324                         GOTO(out, rc = -EBUSY);
 325
 326                 lmv_stripe_count = le32_to_cpu(lmv->lmv_stripe_count);
 327
 328                 /* save stripe to clear 'restriping' flag in the end to avoid
 329                  * trigger auto-split multiple times.
 330                  */
 331                 stripe = child;
 332                 child = NULL;
 333
 334                 /* get master object FID from linkea */
 335                 rc = mdt_attr_get_pfid(info, stripe, &ma->ma_pfid);
 336                 if (rc)
 337                         GOTO(out, rc);
 338
 339                 child = mdt_object_find(env, mdt, &ma->ma_pfid);
 340                 if (IS_ERR(child))
 341                         GOTO(out, rc = PTR_ERR(child));
 342
 343                 spin_lock(&restriper->mdr_lock);
 344                 if (child->mot_restriping) {
 345                         /* race? */
 346                         spin_unlock(&restriper->mdr_lock);
 347                         GOTO(out, rc = -EBUSY);
 348                 }
 349                 child->mot_restriping = 1;
 350                 spin_unlock(&restriper->mdr_lock);
 351
 352                 /* skip if master object is remote, let the first stripe
 353                  * to start splitting because dir split needs to be done
 354                  * on where master object is.
 355                  */
 356                 if (mdt_object_remote(child))
 357                         GOTO(restriping_clear, rc = -EREMOTE);
 358         }
 359
 360         /* striped directory split adds mdr_auto_split_delta stripes */
 361         lum_stripe_count = min_t(unsigned int,
 362                                 lmv_stripe_count +
 363                                         mdt->mdt_restriper.mdr_dir_split_delta,
 364                                 atomic_read(&mdt->mdt_mds_mds_conns) + 1);
 365         if (lmv_stripe_count >= lum_stripe_count)
 366                 GOTO(restriping_clear, rc = -EALREADY);
 367
 368         /* get dir name and parent FID */
 369         rc = mdt_attr_get_pfid_name(info, child, fid, lname);
 370         if (rc)
 371                 GOTO(restriping_clear, rc);
 372
 373         /* copy name out because mti_linkea will be used later, and name should
 374          * end with '\0'
 375          */
 376         memcpy(info->mti_filename, lname->ln_name, lname->ln_namelen);
 377         info->mti_filename[lname->ln_namelen] = '\0';
 378         lname->ln_name = info->mti_filename;
 379         CDEBUG(D_INFO, "split "DFID"/"DNAME" to count %u (MDT count %d)\n",
 380                PFID(fid), PNAME(lname), lum_stripe_count,
 381                atomic_read(&mdt->mdt_mds_mds_conns) + 1);
 382
 383         parent = mdt_object_find(env, mdt, fid);
 384         if (IS_ERR(parent))
 385                 GOTO(restriping_clear, rc = PTR_ERR(parent));
 386
 387         rc = mdt_fid_alloc(env, mdt, fid, child, NULL);
 388         if (rc < 0)
 389                 GOTO(restriping_clear, rc);
 390
 391         lhp = &info->mti_lh[MDT_LH_PARENT];
 392         mdt_lock_pdo_init(lhp, LCK_PW, lname);
 393         rc = mdt_reint_object_lock(info, parent, lhp, MDS_INODELOCK_UPDATE,
 394                                    true);
 395         if (rc)
 396                 GOTO(restriping_clear, rc);
 397
 398         lhc = &info->mti_lh[MDT_LH_CHILD];
 399         mdt_lock_reg_init(lhc, LCK_EX);
 400         if (mdt_object_remote(parent)) {
 401                 /* enqueue object remote LOOKUP lock */
 402                 rc = mdt_remote_object_lock(info, parent, mdt_object_fid(child),
 403                                             &lhc->mlh_rreg_lh,
 404                                             lhc->mlh_rreg_mode,
 405                                             MDS_INODELOCK_LOOKUP, false);
 406                 if (rc != ELDLM_OK)
 407                         GOTO(unlock_parent, rc);
 408         }
 409
 410         rc = mdt_reint_striped_lock(info, child, lhc, MDS_INODELOCK_FULL, einfo,
 411                                     true);
 412         if (rc)
 413                 GOTO(unlock_child, rc);
 414
 415         mdt_auto_split_prep(info, spec, ma, lum_stripe_count);
 416
 417         rc = mdt_restripe_internal(info, parent, child, lname, fid, spec, ma);
 418         EXIT;
 419
 420 unlock_child:
 421         mdt_reint_striped_unlock(info, child, lhc, einfo, rc);
 422 unlock_parent:
 423         mdt_object_unlock(info, parent, lhp, rc);
 424 restriping_clear:
 425         child->mot_restriping = 0;
 426         LASSERT(list_empty(&child->mot_restripe_linkage));
 427 out:
 428         /* -EALREADY:   dir is split already.
 429          * -EBUSY:      dir is opened, or is splitting by others.
 430          * -EREMOTE:    dir is remote.
 431          */
 432         if (rc && rc != -EALREADY && rc != -EBUSY && rc != -EREMOTE)
 433                 CERROR("%s: split "DFID"/"DNAME" to count %u failed: rc = %d\n",
 434                        mdt_obd_name(mdt), PFID(mdt_object_fid(child)),
 435                        PNAME(lname), lum_stripe_count, rc);
 436
 437         if (!IS_ERR_OR_NULL(child))
 438                 mdt_object_put(env, child);
 439
 440         if (stripe) {
 441                 LASSERT(stripe->mot_restriping);
 442                 LASSERT(list_empty(&stripe->mot_restripe_linkage));
 443                 stripe->mot_restriping = 0;
 444                 /* lock may not be taken, don't cache stripe LMV */
 445                 mo_invalidate(env, mdt_object_child(stripe));
 446                 mdt_object_put(env, stripe);
 447         }
 448
 449         if (!IS_ERR_OR_NULL(parent))
 450                 mdt_object_put(env, parent);
 451
 452         return rc;
 453 }
 454
 455 /* sub-files under one stripe are migrated, clear MIGRATION flag in its LMV */
 456 static int mdt_restripe_migrate_finish(struct mdt_thread_info *info,
 457                                        struct mdt_object *stripe,
 458                                        struct lmv_mds_md_v1 *lmv)
 459 {
 460         struct mdt_device *mdt = info->mti_mdt;
 461         struct lu_buf buf;
 462         struct mdt_lock_handle *lh;
 463         int rc;
 464
 465         ENTRY;
 466
 467         LASSERT(le32_to_cpu(lmv->lmv_magic) == LMV_MAGIC_STRIPE);
 468         LASSERT(lmv_is_restriping(lmv));
 469
 470         lmv->lmv_hash_type &= ~cpu_to_le32(LMV_HASH_FLAG_MIGRATION);
 471         buf.lb_buf = lmv;
 472         buf.lb_len = sizeof(*lmv);
 473
 474         lh = &info->mti_lh[MDT_LH_PARENT];
 475         mdt_lock_reg_init(lh, LCK_EX);
 476         rc = mdt_reint_object_lock(info, stripe, lh, MDS_INODELOCK_XATTR,
 477                                    false);
 478         if (!rc)
 479                 rc = mo_xattr_set(info->mti_env, mdt_object_child(stripe), &buf,
 480                                   XATTR_NAME_LMV, LU_XATTR_REPLACE);
 481         mdt_object_unlock(info, stripe, lh, rc);
 482         if (rc)
 483                 CERROR("%s: update "DFID" LMV failed: rc = %d\n",
 484                        mdt_obd_name(mdt), PFID(mdt_object_fid(stripe)), rc);
 485
 486         LASSERT(!list_empty(&stripe->mot_restripe_linkage));
 487         LASSERT(stripe->mot_restriping);
 488
 489         spin_lock(&mdt->mdt_lock);
 490         stripe->mot_restriping = 0;
 491         list_del_init(&stripe->mot_restripe_linkage);
 492         spin_unlock(&mdt->mdt_lock);
 493
 494         mdt_object_put(info->mti_env, stripe);
 495
 496         RETURN(rc);
 497 }
 498
 499 static void mdt_restripe_migrate_prep(struct mdt_thread_info *info,
 500                                       const struct lu_fid *fid1,
 501                                       const struct lu_fid *fid2,
 502                                       const struct lu_name *lname,
 503                                       __u16 type,
 504                                       const struct lmv_mds_md_v1 *lmv)
 505 {
 506         struct lu_attr *attr = &info->mti_attr.ma_attr;
 507         struct mdt_reint_record *rr = &info->mti_rr;
 508         struct md_op_spec *spec = &info->mti_spec;
 509         struct lmv_user_md_v1 *lum;
 510
 511         attr->la_ctime = attr->la_mtime = ktime_get_real_seconds();
 512         attr->la_valid = LA_CTIME | LA_MTIME;
 513
 514         rr->rr_fid1 = fid1;
 515         rr->rr_fid2 = fid2;
 516         rr->rr_name = *lname;
 517
 518         lum = &info->mti_mdt->mdt_restriper.mdr_lmv.lmv_user_md;
 519         lum->lum_magic = cpu_to_le32(LMV_USER_MAGIC);
 520         lum->lum_stripe_offset = cpu_to_le32(LMV_OFFSET_DEFAULT);
 521         if (lmv_is_splitting(lmv)) {
 522                 lum->lum_stripe_count = lmv->lmv_stripe_count;
 523                 lum->lum_hash_type =
 524                         lmv->lmv_hash_type & le32_to_cpu(LMV_HASH_TYPE_MASK);
 525         } else if (lmv_is_merging(lmv)) {
 526                 lum->lum_stripe_count = lmv->lmv_merge_offset;
 527                 lum->lum_hash_type = lmv->lmv_merge_hash;
 528         }
 529
 530         spec->u.sp_ea.eadatalen = sizeof(*lum);
 531         spec->u.sp_ea.eadata = lum;
 532         spec->sp_cr_flags = MDS_OPEN_HAS_EA;
 533         spec->no_create = 0;
 534         spec->sp_migrate_close = 0;
 535         /* if 'nsonly' is set, don't migrate inode */
 536         if (S_ISDIR(type))
 537                 spec->sp_migrate_nsonly = 1;
 538         else
 539                 spec->sp_migrate_nsonly =
 540                         info->mti_mdt->mdt_dir_restripe_nsonly;
 541 }
 542
 543 /* migrate sub-file from @mdr_restripe_offset */
 544 static int mdt_restripe_migrate(struct mdt_thread_info *info)
 545 {
 546         const struct lu_env *env = info->mti_env;
 547         struct mdt_device *mdt = info->mti_mdt;
 548         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 549         struct mdt_object *stripe = NULL;
 550         struct mdt_object *master = NULL;
 551         struct md_attr *ma = &info->mti_attr;
 552         struct lmv_mds_md_v1 *lmv;
 553         struct lu_name *lname = &info->mti_name;
 554         struct lu_rdpg *rdpg = &info->mti_u.rdpg.mti_rdpg;
 555         struct lu_fid fid1;
 556         struct lu_fid fid2;
 557         struct lu_dirpage *dp;
 558         struct lu_dirent *ent;
 559         const char *name = NULL;
 560         int namelen = 0;
 561         __u16 type;
 562         int idx = 0;
 563         int len;
 564         int rc;
 565
 566         ENTRY;
 567
 568         if (list_empty(&restriper->mdr_migrating))
 569                 RETURN(0);
 570
 571         stripe = list_entry(restriper->mdr_migrating.next, typeof(*stripe),
 572                             mot_restripe_linkage);
 573
 574         /* get master object FID and stripe name */
 575         rc = mdt_attr_get_pfid_name(info, stripe, &fid1, lname);
 576         if (rc)
 577                 GOTO(out, rc);
 578
 579         snprintf(info->mti_filename, sizeof(info->mti_filename), DFID,
 580                  PFID(mdt_object_fid(stripe)));
 581         len = strlen(info->mti_filename) + 1;
 582         if (len >= lname->ln_namelen)
 583                 GOTO(out, rc = -EBADF);
 584
 585         while (len < lname->ln_namelen) {
 586                 if (!isdigit(lname->ln_name[len]))
 587                         GOTO(out, rc = -EBADF);
 588
 589                 idx = idx * 10 + lname->ln_name[len++] - '0';
 590         };
 591
 592         /* check whether stripe is newly created in split */
 593         rc = mdt_stripe_get(info, stripe, ma, XATTR_NAME_LMV);
 594         if (rc)
 595                 GOTO(out, rc);
 596
 597         if (!(ma->ma_valid & MA_LMV))
 598                 GOTO(out, rc = -ENODATA);
 599
 600         lmv = &ma->ma_lmv->lmv_md_v1;
 601         if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_STRIPE)
 602                 GOTO(out, rc = -EBADF);
 603
 604         if (!lmv_is_restriping(lmv))
 605                 GOTO(out, rc = -EINVAL);
 606
 607         if ((lmv_is_splitting(lmv) &&
 608              idx >= le32_to_cpu(lmv->lmv_split_offset)) ||
 609             (lmv_is_merging(lmv) &&
 610              (le32_to_cpu(lmv->lmv_hash_type) & LMV_HASH_TYPE_MASK) ==
 611                 LMV_HASH_TYPE_CRUSH &&
 612              idx < le32_to_cpu(lmv->lmv_merge_offset))) {
 613                 /* new stripes doesn't need to migrate sub files in dir
 614                  * split, neither for target stripes in dir merge if hash type
 615                  * is CRUSH.
 616                  */
 617                 rc = mdt_restripe_migrate_finish(info, stripe, lmv);
 618                 RETURN(rc);
 619         }
 620
 621         /* get sub file name @mot_restripe_offset.
 622          * TODO: read one dirent instead of whole page.
 623          */
 624         rdpg->rp_hash = stripe->mot_restripe_offset;
 625         rdpg->rp_count = PAGE_SIZE;
 626         rdpg->rp_npages = 1;
 627         rdpg->rp_attrs = LUDA_64BITHASH | LUDA_FID | LUDA_TYPE;
 628         rdpg->rp_pages = &restriper->mdr_page;
 629         rc = mo_readpage(env, mdt_object_child(stripe), rdpg);
 630         if (rc < 0)
 631                 GOTO(out, rc);
 632
 633         dp = page_address(restriper->mdr_page);
 634         for (ent = lu_dirent_start(dp); ent; ent = lu_dirent_next(ent)) {
 635                 LASSERT(le64_to_cpu(ent->lde_hash) >= rdpg->rp_hash);
 636
 637                 if (unlikely(!(le32_to_cpu(ent->lde_attrs) & LUDA_TYPE)))
 638                         GOTO(out, rc = -EINVAL);
 639
 640                 namelen = le16_to_cpu(ent->lde_namelen);
 641                 if (!namelen)
 642                         continue;
 643
 644                 if (name_is_dot_or_dotdot(ent->lde_name, namelen))
 645                         continue;
 646
 647                 name = ent->lde_name;
 648                 type = lu_dirent_type_get(ent);
 649                 break;
 650         }
 651
 652         if (!name) {
 653                 if (le64_to_cpu(dp->ldp_hash_end) == MDS_DIR_END_OFF) {
 654                         rc = mdt_restripe_migrate_finish(info, stripe, lmv);
 655                         RETURN(rc);
 656                 }
 657
 658                 GOTO(out, rc = -EBADF);
 659         }
 660
 661         /* copy name out because it should end with '\0' */
 662         memcpy(info->mti_filename, name, namelen);
 663         info->mti_filename[namelen] = '\0';
 664         lname->ln_name = info->mti_filename;
 665         lname->ln_namelen = namelen;
 666
 667         CDEBUG(D_INFO, "migrate "DFID"/"DNAME" type %ho\n",
 668                PFID(&fid1), PNAME(lname), type);
 669
 670         master = mdt_object_find(env, mdt, &fid1);
 671         if (IS_ERR(master))
 672                 GOTO(out, rc = PTR_ERR(master));
 673
 674         rc = mdt_fid_alloc(env, mdt, &fid2, master, lname);
 675         mdt_object_put(env, master);
 676         if (rc < 0)
 677                 GOTO(out, rc);
 678
 679         mdt_restripe_migrate_prep(info, &fid1, &fid2, lname, type, lmv);
 680
 681         rc = mdt_reint_migrate(info, NULL);
 682         /* mti_big_buf is allocated in XATTR migration */
 683         if (unlikely(info->mti_big_buf.lb_buf))
 684                 lu_buf_free(&info->mti_big_buf);
 685         if (rc == -EALREADY)
 686                 rc = 0;
 687         if (rc)
 688                 GOTO(out, rc);
 689
 690         LASSERT(ent);
 691         do {
 692                 ent = lu_dirent_next(ent);
 693                 if (!ent)
 694                         break;
 695
 696                 namelen = le16_to_cpu(ent->lde_namelen);
 697         } while (namelen == 0); /* Skip dummy record */
 698
 699         if (ent)
 700                 stripe->mot_restripe_offset = le64_to_cpu(ent->lde_hash);
 701         else
 702                 stripe->mot_restripe_offset = le64_to_cpu(dp->ldp_hash_end);
 703
 704         EXIT;
 705 out:
 706         if (rc) {
 707                 /* -EBUSY: file is opened by others */
 708                 if (rc != -EBUSY)
 709                         CERROR("%s: migrate "DFID"/"DNAME" failed: rc = %d\n",
 710                                mdt_obd_name(mdt), PFID(&fid1), PNAME(lname),
 711                                rc);
 712
 713                 spin_lock(&mdt->mdt_lock);
 714                 stripe->mot_restriping = 0;
 715                 list_del_init(&stripe->mot_restripe_linkage);
 716                 spin_unlock(&mdt->mdt_lock);
 717
 718                 mdt_object_put(env, stripe);
 719         }
 720
 721         return rc;
 722 }
 723
 724 static inline bool mdt_restripe_update_pending(struct mdt_thread_info *info)
 725 {
 726         struct mdt_device *mdt = info->mti_mdt;
 727
 728         if (list_empty(&mdt->mdt_restriper.mdr_updating))
 729                 return false;
 730
 731         return mdt->mdt_restriper.mdr_update_time < ktime_get_real_seconds();
 732 }
 733
 734 static void mdt_restripe_layout_update_prep(struct mdt_thread_info *info,
 735                                             const struct lu_fid *fid,
 736                                             const struct lmv_mds_md_v1 *lmv)
 737 {
 738         struct lu_attr *attr = &info->mti_attr.ma_attr;
 739         struct mdt_reint_record *rr = &info->mti_rr;
 740         struct lmv_user_md_v1 *lum;
 741
 742         attr->la_ctime = attr->la_mtime = ktime_get_real_seconds();
 743         attr->la_valid = LA_CTIME | LA_MTIME;
 744
 745         strncpy(info->mti_filename, XATTR_NAME_LMV,
 746                 sizeof(info->mti_filename));
 747
 748         lum = &info->mti_mdt->mdt_restriper.mdr_lmv.lmv_user_md;
 749         lum->lum_magic = cpu_to_le32(LMV_USER_MAGIC);
 750         lum->lum_stripe_offset = cpu_to_le32(LMV_OFFSET_DEFAULT);
 751         if (lmv_is_splitting(lmv)) {
 752                 lum->lum_stripe_count = lmv->lmv_stripe_count;
 753                 lum->lum_hash_type =
 754                         lmv->lmv_hash_type & le32_to_cpu(LMV_HASH_TYPE_MASK);
 755         } else if (lmv_is_merging(lmv)) {
 756                 lum->lum_stripe_count = lmv->lmv_merge_offset;
 757                 lum->lum_hash_type = lmv->lmv_merge_hash;
 758         }
 759
 760         rr->rr_opcode = REINT_SETXATTR;
 761         rr->rr_fid1 = fid;
 762         rr->rr_name.ln_name = info->mti_filename;
 763         rr->rr_name.ln_namelen = strlen(info->mti_filename);
 764         rr->rr_eadata = lum;
 765         rr->rr_eadatalen = sizeof(*lum);
 766 }
 767
 768 static int mdt_restripe_layout_update(struct mdt_thread_info *info)
 769 {
 770         const struct lu_env *env = info->mti_env;
 771         struct mdt_device *mdt = info->mti_mdt;
 772         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 773         struct md_attr *ma = &info->mti_attr;
 774         struct lu_fid *fid = &info->mti_tmp_fid1;
 775         struct mdt_object *master;
 776         struct mdt_object *stripe;
 777         struct lmv_mds_md_v1 *lmv;
 778         int i;
 779         int rc;
 780
 781         ENTRY;
 782
 783         if (list_empty(&restriper->mdr_updating))
 784                 RETURN(0);
 785
 786         master = list_entry(restriper->mdr_updating.next, typeof(*master),
 787                             mot_restripe_linkage);
 788
 789         rc = mdt_stripe_get(info, master, ma, XATTR_NAME_LMV);
 790         if (rc)
 791                 GOTO(out, rc);
 792
 793         if (!(ma->ma_valid & MA_LMV))
 794                 GOTO(out, rc = -ENODATA);
 795
 796         lmv = &ma->ma_lmv->lmv_md_v1;
 797         if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_V1)
 798                 GOTO(out, rc = -EBADF);
 799
 800         if (!lmv_is_restriping(lmv))
 801                 GOTO(out, rc = -EINVAL);
 802
 803         /* use different buffer to store stripe LMV */
 804         ma->ma_lmv = &restriper->mdr_lmv;
 805         ma->ma_lmv_size = sizeof(restriper->mdr_lmv);
 806         for (i = 0; i < le32_to_cpu(lmv->lmv_stripe_count); i++) {
 807                 fid_le_to_cpu(fid, &lmv->lmv_stripe_fids[i]);
 808                 stripe = mdt_object_find(env, mdt, fid);
 809                 if (IS_ERR(stripe))
 810                         GOTO(out, rc = PTR_ERR(stripe));
 811
 812                 ma->ma_valid = 0;
 813                 rc = __mdt_stripe_get(info, stripe, ma, XATTR_NAME_LMV);
 814                 /* LMV is checked without lock, don't cache it */
 815                 mo_invalidate(env, mdt_object_child(stripe));
 816                 mdt_object_put(env, stripe);
 817                 if (rc)
 818                         GOTO(out, rc);
 819
 820                 if (!(ma->ma_valid & MA_LMV))
 821                         GOTO(out, rc = -ENODATA);
 822
 823                 /* check MIGRATION flag cleared on all stripes */
 824                 if (lmv_is_restriping(&ma->ma_lmv->lmv_md_v1))
 825                         GOTO(out, rc = -EINPROGRESS);
 826         }
 827
 828         mdt_restripe_layout_update_prep(info, mdt_object_fid(master), lmv);
 829
 830         rc = mdt_dir_layout_update(info);
 831         if (rc) {
 832                 CERROR("update "DFID" layout failed: rc = %d\n",
 833                        PFID(mdt_object_fid(master)), rc);
 834                 GOTO(out, rc);
 835         }
 836
 837 out:
 838         LASSERT(!list_empty(&master->mot_restripe_linkage));
 839         if (rc == -EINPROGRESS) {
 840                 restriper->mdr_update_time = ktime_get_real_seconds() + 5;
 841         } else {
 842                 spin_lock(&restriper->mdr_lock);
 843                 master->mot_restriping = 0;
 844                 list_del_init(&master->mot_restripe_linkage);
 845                 spin_unlock(&restriper->mdr_lock);
 846
 847                 mdt_object_put(env, master);
 848         }
 849
 850         return rc;
 851 }
 852
 853 static int mdt_restriper_main(void *arg)
 854 {
 855         struct mdt_thread_info *info = arg;
 856         struct mdt_device *mdt = info->mti_mdt;
 857         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 858
 859         ENTRY;
 860
 861         while (({set_current_state(TASK_IDLE);
 862                  !kthread_should_stop(); })) {
 863                 if (!list_empty(&restriper->mdr_auto_splitting)) {
 864                         __set_current_state(TASK_RUNNING);
 865                         mdt_auto_split(info);
 866                         cond_resched();
 867                 } else if (mdt_restripe_update_pending(info)) {
 868                         __set_current_state(TASK_RUNNING);
 869                         mdt_restripe_layout_update(info);
 870                         cond_resched();
 871                 } else if (!list_empty(&restriper->mdr_migrating)) {
 872                         __set_current_state(TASK_RUNNING);
 873                         mdt_restripe_migrate(info);
 874                         cond_resched();
 875                 } else {
 876                         schedule();
 877                 }
 878         }
 879         __set_current_state(TASK_RUNNING);
 880
 881         RETURN(0);
 882 }
 883
 884 int mdt_restriper_start(struct mdt_device *mdt)
 885 {
 886         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 887         kernel_cap_t kcap = cap_combine(CAP_FS_SET, CAP_NFSD_SET);
 888         struct task_struct *task;
 889         struct mdt_thread_info *info;
 890         struct lu_ucred *uc;
 891         int rc;
 892
 893         ENTRY;
 894
 895         spin_lock_init(&restriper->mdr_lock);
 896         INIT_LIST_HEAD(&restriper->mdr_auto_splitting);
 897         INIT_LIST_HEAD(&restriper->mdr_migrating);
 898         INIT_LIST_HEAD(&restriper->mdr_updating);
 899         restriper->mdr_dir_split_count = DIR_SPLIT_COUNT_DEFAULT;
 900         restriper->mdr_dir_split_delta = DIR_SPLIT_DELTA_DEFAULT;
 901
 902         restriper->mdr_page = alloc_page(GFP_KERNEL);
 903         if (!restriper->mdr_page)
 904                 RETURN(-ENOMEM);
 905
 906         rc = lu_env_init(&restriper->mdr_env, LCT_MD_THREAD);
 907         if (rc)
 908                 GOTO(out_page, rc);
 909
 910         rc = lu_context_init(&restriper->mdr_session, LCT_SERVER_SESSION);
 911         if (rc)
 912                 GOTO(out_env, rc);
 913
 914         lu_context_enter(&restriper->mdr_session);
 915         restriper->mdr_env.le_ses = &restriper->mdr_session;
 916
 917         info = lu_context_key_get(&restriper->mdr_env.le_ctx, &mdt_thread_key);
 918         info->mti_env = &restriper->mdr_env;
 919         info->mti_mdt = mdt;
 920         info->mti_pill = NULL;
 921         info->mti_dlm_req = NULL;
 922
 923         uc = mdt_ucred(info);
 924         uc->uc_valid = UCRED_OLD;
 925         uc->uc_o_uid = 0;
 926         uc->uc_o_gid = 0;
 927         uc->uc_o_fsuid = 0;
 928         uc->uc_o_fsgid = 0;
 929         uc->uc_uid = 0;
 930         uc->uc_gid = 0;
 931         uc->uc_fsuid = 0;
 932         uc->uc_fsgid = 0;
 933         uc->uc_suppgids[0] = -1;
 934         uc->uc_suppgids[1] = -1;
 935         uc->uc_cap = kcap.cap[0];
 936         uc->uc_umask = 0644;
 937         uc->uc_ginfo = NULL;
 938         uc->uc_identity = NULL;
 939
 940         task = kthread_create(mdt_restriper_main, info, "mdt_restriper_%03d",
 941                               mdt_seq_site(mdt)->ss_node_id);
 942         if (IS_ERR(task)) {
 943                 rc = PTR_ERR(task);
 944                 CERROR("%s: Can't start directory restripe thread: rc %d\n",
 945                        mdt_obd_name(mdt), rc);
 946                 GOTO(out_ses, rc);
 947         }
 948         restriper->mdr_task = task;
 949         wake_up_process(task);
 950
 951         RETURN(0);
 952
 953 out_ses:
 954         lu_context_exit(restriper->mdr_env.le_ses);
 955         lu_context_fini(restriper->mdr_env.le_ses);
 956 out_env:
 957         lu_env_fini(&restriper->mdr_env);
 958 out_page:
 959         __free_page(restriper->mdr_page);
 960
 961         return rc;
 962 }
 963
 964 void mdt_restriper_stop(struct mdt_device *mdt)
 965 {
 966         struct mdt_dir_restriper *restriper = &mdt->mdt_restriper;
 967         struct lu_env *env = &restriper->mdr_env;
 968         struct mdt_object *mo, *next;
 969
 970         if (!restriper->mdr_task)
 971                 return;
 972
 973         kthread_stop(restriper->mdr_task);
 974         restriper->mdr_task = NULL;
 975
 976         list_for_each_entry_safe(mo, next, &restriper->mdr_auto_splitting,
 977                                  mot_restripe_linkage) {
 978                 list_del_init(&mo->mot_restripe_linkage);
 979                 mdt_object_put(env, mo);
 980         }
 981
 982         list_for_each_entry_safe(mo, next, &restriper->mdr_migrating,
 983                                  mot_restripe_linkage) {
 984                 list_del_init(&mo->mot_restripe_linkage);
 985                 mdt_object_put(env, mo);
 986         }
 987
 988         list_for_each_entry_safe(mo, next, &restriper->mdr_updating,
 989                                  mot_restripe_linkage) {
 990                 list_del_init(&mo->mot_restripe_linkage);
 991                 mdt_object_put(env, mo);
 992         }
 993
 994         __free_page(restriper->mdr_page);
 995
 996         lu_context_exit(env->le_ses);
 997         lu_context_fini(env->le_ses);
 998         lu_env_fini(env);
 999 }