lustre/llite/vvp_dev.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  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2012, 2016, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  *
  31  * cl_device and cl_device_type implementation for VVP layer.
  32  *
  33  *   Author: Nikita Danilov <nikita.danilov@sun.com>
  34  *   Author: Jinshan Xiong <jinshan.xiong@intel.com>
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LLITE
  38
  39 #include <obd.h>
  40 #include "llite_internal.h"
  41 #include "vvp_internal.h"
  42 #include <linux/kallsyms.h>
  43
  44 /*****************************************************************************
  45  *
  46  * Vvp device and device type functions.
  47  *
  48  */
  49
  50 /*
  51  * vvp_ prefix stands for "Vfs Vm Posix". It corresponds to historical
  52  * "llite_" (var. "ll_") prefix.
  53  */
  54
  55 static struct kmem_cache *ll_thread_kmem;
  56 struct kmem_cache *vvp_object_kmem;
  57 static struct kmem_cache *vvp_session_kmem;
  58 static struct kmem_cache *vvp_thread_kmem;
  59
  60 static struct lu_kmem_descr vvp_caches[] = {
  61         {
  62                 .ckd_cache = &ll_thread_kmem,
  63                 .ckd_name  = "ll_thread_kmem",
  64                 .ckd_size  = sizeof(struct ll_thread_info),
  65         },
  66         {
  67                 .ckd_cache = &vvp_object_kmem,
  68                 .ckd_name  = "vvp_object_kmem",
  69                 .ckd_size  = sizeof(struct vvp_object),
  70         },
  71         {
  72                 .ckd_cache = &vvp_session_kmem,
  73                 .ckd_name  = "vvp_session_kmem",
  74                 .ckd_size  = sizeof (struct vvp_session)
  75         },
  76         {
  77                 .ckd_cache = &vvp_thread_kmem,
  78                 .ckd_name  = "vvp_thread_kmem",
  79                 .ckd_size  = sizeof(struct vvp_thread_info),
  80         },
  81         {
  82                 .ckd_cache = NULL
  83         }
  84 };
  85
  86 static void *ll_thread_key_init(const struct lu_context *ctx,
  87                                 struct lu_context_key *key)
  88 {
  89         struct ll_thread_info *lti;
  90
  91         OBD_SLAB_ALLOC_PTR_GFP(lti, ll_thread_kmem, GFP_NOFS);
  92         if (lti == NULL)
  93                 lti = ERR_PTR(-ENOMEM);
  94
  95         return lti;
  96 }
  97
  98 static void ll_thread_key_fini(const struct lu_context *ctx,
  99                                struct lu_context_key *key, void *data)
 100 {
 101         struct ll_thread_info *lti = data;
 102
 103         OBD_SLAB_FREE_PTR(lti, ll_thread_kmem);
 104 }
 105
 106 struct lu_context_key ll_thread_key = {
 107         .lct_tags = LCT_CL_THREAD,
 108         .lct_init = ll_thread_key_init,
 109         .lct_fini = ll_thread_key_fini,
 110 };
 111
 112 static void *vvp_session_key_init(const struct lu_context *ctx,
 113                                   struct lu_context_key *key)
 114 {
 115         struct vvp_session *session;
 116
 117         OBD_SLAB_ALLOC_PTR_GFP(session, vvp_session_kmem, GFP_NOFS);
 118         if (session == NULL)
 119                 session = ERR_PTR(-ENOMEM);
 120         return session;
 121 }
 122
 123 static void vvp_session_key_fini(const struct lu_context *ctx,
 124                                  struct lu_context_key *key, void *data)
 125 {
 126         struct vvp_session *session = data;
 127         OBD_SLAB_FREE_PTR(session, vvp_session_kmem);
 128 }
 129
 130 struct lu_context_key vvp_session_key = {
 131         .lct_tags = LCT_SESSION,
 132         .lct_init = vvp_session_key_init,
 133         .lct_fini = vvp_session_key_fini
 134 };
 135
 136 static void *vvp_thread_key_init(const struct lu_context *ctx,
 137                                  struct lu_context_key *key)
 138 {
 139         struct vvp_thread_info *vti;
 140
 141         OBD_SLAB_ALLOC_PTR_GFP(vti, vvp_thread_kmem, GFP_NOFS);
 142         if (vti == NULL)
 143                 vti = ERR_PTR(-ENOMEM);
 144         return vti;
 145 }
 146
 147 static void vvp_thread_key_fini(const struct lu_context *ctx,
 148                                 struct lu_context_key *key, void *data)
 149 {
 150         struct vvp_thread_info *vti = data;
 151         OBD_SLAB_FREE_PTR(vti, vvp_thread_kmem);
 152 }
 153
 154 struct lu_context_key vvp_thread_key = {
 155         .lct_tags = LCT_CL_THREAD,
 156         .lct_init = vvp_thread_key_init,
 157         .lct_fini = vvp_thread_key_fini,
 158 };
 159
 160 /* type constructor/destructor: vvp_type_{init,fini,start,stop}(). */
 161 LU_TYPE_INIT_FINI(vvp, &ll_thread_key, &vvp_session_key, &vvp_thread_key);
 162
 163 static const struct lu_device_operations vvp_lu_ops = {
 164         .ldo_object_alloc      = vvp_object_alloc
 165 };
 166
 167 static struct lu_device *vvp_device_free(const struct lu_env *env,
 168                                          struct lu_device *d)
 169 {
 170         struct vvp_device *vdv  = lu2vvp_dev(d);
 171         struct cl_site    *site = lu2cl_site(d->ld_site);
 172         struct lu_device  *next = cl2lu_dev(vdv->vdv_next);
 173
 174         if (d->ld_site != NULL) {
 175                 cl_site_fini(site);
 176                 OBD_FREE_PTR(site);
 177         }
 178
 179         cl_device_fini(lu2cl_dev(d));
 180         OBD_FREE_PTR(vdv);
 181         return next;
 182 }
 183
 184 static struct lu_device *vvp_device_alloc(const struct lu_env *env,
 185                                           struct lu_device_type *t,
 186                                           struct lustre_cfg *cfg)
 187 {
 188         struct vvp_device *vdv;
 189         struct lu_device *lud;
 190         struct cl_site *site;
 191         int rc;
 192         ENTRY;
 193
 194         OBD_ALLOC_PTR(vdv);
 195         if (vdv == NULL)
 196                 RETURN(ERR_PTR(-ENOMEM));
 197
 198         lud = &vdv->vdv_cl.cd_lu_dev;
 199         cl_device_init(&vdv->vdv_cl, t);
 200         vvp2lu_dev(vdv)->ld_ops = &vvp_lu_ops;
 201
 202         OBD_ALLOC_PTR(site);
 203         if (site != NULL) {
 204                 rc = cl_site_init(site, &vdv->vdv_cl);
 205                 if (rc == 0)
 206                         rc = lu_site_init_finish(&site->cs_lu);
 207                 else {
 208                         LASSERT(lud->ld_site == NULL);
 209                         CERROR("Cannot init lu_site, rc %d.\n", rc);
 210                         OBD_FREE_PTR(site);
 211                 }
 212         } else
 213                 rc = -ENOMEM;
 214         if (rc != 0) {
 215                 vvp_device_free(env, lud);
 216                 lud = ERR_PTR(rc);
 217         }
 218         RETURN(lud);
 219 }
 220
 221 static int vvp_device_init(const struct lu_env *env, struct lu_device *d,
 222                            const char *name, struct lu_device *next)
 223 {
 224         struct vvp_device  *vdv;
 225         int rc;
 226         ENTRY;
 227
 228         vdv = lu2vvp_dev(d);
 229         vdv->vdv_next = lu2cl_dev(next);
 230
 231         LASSERT(d->ld_site != NULL && next->ld_type != NULL);
 232         next->ld_site = d->ld_site;
 233         rc = next->ld_type->ldt_ops->ldto_device_init(
 234                 env, next, next->ld_type->ldt_name, NULL);
 235         if (rc == 0) {
 236                 lu_device_get(next);
 237                 lu_ref_add(&next->ld_reference, "lu-stack", &lu_site_init);
 238         }
 239         RETURN(rc);
 240 }
 241
 242 static struct lu_device *vvp_device_fini(const struct lu_env *env,
 243                                          struct lu_device *d)
 244 {
 245         return cl2lu_dev(lu2vvp_dev(d)->vdv_next);
 246 }
 247
 248 static const struct lu_device_type_operations vvp_device_type_ops = {
 249         .ldto_init = vvp_type_init,
 250         .ldto_fini = vvp_type_fini,
 251
 252         .ldto_start = vvp_type_start,
 253         .ldto_stop  = vvp_type_stop,
 254
 255         .ldto_device_alloc      = vvp_device_alloc,
 256         .ldto_device_free       = vvp_device_free,
 257         .ldto_device_init       = vvp_device_init,
 258         .ldto_device_fini       = vvp_device_fini,
 259 };
 260
 261 struct lu_device_type vvp_device_type = {
 262         .ldt_tags     = LU_DEVICE_CL,
 263         .ldt_name     = LUSTRE_VVP_NAME,
 264         .ldt_ops      = &vvp_device_type_ops,
 265         .ldt_ctx_tags = LCT_CL_THREAD
 266 };
 267
 268 unsigned int (*vvp_account_page_dirtied)(struct page *page,
 269                                          struct address_space *mapping);
 270
 271 /**
 272  * A mutex serializing calls to vvp_inode_fini() under extreme memory
 273  * pressure, when environments cannot be allocated.
 274  */
 275 int vvp_global_init(void)
 276 {
 277         int rc;
 278
 279         rc = lu_kmem_init(vvp_caches);
 280         if (rc != 0)
 281                 return rc;
 282
 283         rc = lu_device_type_init(&vvp_device_type);
 284         if (rc != 0)
 285                 goto out_kmem;
 286
 287 #ifndef HAVE_ACCOUNT_PAGE_DIRTIED_EXPORT
 288 #ifdef HAVE_KALLSYMS_LOOKUP_NAME
 289         /*
 290          * Kernel v5.2-5678-gac1c3e4 no longer exports account_page_dirtied
 291          */
 292         vvp_account_page_dirtied = (void *)
 293                 cfs_kallsyms_lookup_name("account_page_dirtied");
 294 #endif
 295 #endif
 296
 297         return 0;
 298
 299 out_kmem:
 300         lu_kmem_fini(vvp_caches);
 301
 302         return rc;
 303 }
 304
 305 void vvp_global_fini(void)
 306 {
 307         lu_device_type_fini(&vvp_device_type);
 308         lu_kmem_fini(vvp_caches);
 309 }
 310
 311 /*****************************************************************************
 312  *
 313  * mirror obd-devices into cl devices.
 314  *
 315  */
 316
 317 int cl_sb_init(struct super_block *sb)
 318 {
 319         struct ll_sb_info *sbi;
 320         struct cl_device  *cl;
 321         struct lu_env     *env;
 322         int rc = 0;
 323         __u16 refcheck;
 324
 325         sbi  = ll_s2sbi(sb);
 326         env = cl_env_get(&refcheck);
 327         if (!IS_ERR(env)) {
 328                 cl = cl_type_setup(env, NULL, &vvp_device_type,
 329                                    sbi->ll_dt_exp->exp_obd->obd_lu_dev);
 330                 if (!IS_ERR(cl)) {
 331                         sbi->ll_cl = cl;
 332                         sbi->ll_site = cl2lu_dev(cl)->ld_site;
 333                 }
 334                 cl_env_put(env, &refcheck);
 335         } else
 336                 rc = PTR_ERR(env);
 337         RETURN(rc);
 338 }
 339
 340 int cl_sb_fini(struct super_block *sb)
 341 {
 342         struct ll_sb_info *sbi;
 343         struct lu_env     *env;
 344         struct cl_device  *cld;
 345         __u16              refcheck;
 346         int                result;
 347
 348         ENTRY;
 349         sbi = ll_s2sbi(sb);
 350         env = cl_env_get(&refcheck);
 351         if (!IS_ERR(env)) {
 352                 cld = sbi->ll_cl;
 353
 354                 if (cld != NULL) {
 355                         cl_stack_fini(env, cld);
 356                         sbi->ll_cl = NULL;
 357                         sbi->ll_site = NULL;
 358                 }
 359                 cl_env_put(env, &refcheck);
 360                 result = 0;
 361         } else {
 362                 CERROR("Cannot cleanup cl-stack due to memory shortage.\n");
 363                 result = PTR_ERR(env);
 364         }
 365
 366         RETURN(result);
 367 }
 368
 369 /****************************************************************************
 370  *
 371  * debugfs/lustre/llite/$MNT/dump_page_cache
 372  *
 373  ****************************************************************************/
 374
 375 struct vvp_seq_private {
 376         struct ll_sb_info       *vsp_sbi;
 377         struct lu_env           *vsp_env;
 378         u16                     vsp_refcheck;
 379         struct cl_object        *vsp_clob;
 380         struct rhashtable_iter  vsp_iter;
 381         u32                     vsp_page_index;
 382         /*
 383          * prev_pos is the 'pos' of the last object returned
 384          * by ->start of ->next.
 385          */
 386         loff_t                  vvp_prev_pos;
 387 };
 388
 389 static struct page *vvp_pgcache_current(struct vvp_seq_private *priv)
 390 {
 391         struct lu_device *dev = &priv->vsp_sbi->ll_cl->cd_lu_dev;
 392         struct lu_object_header *h;
 393         struct page *vmpage = NULL;
 394
 395         rhashtable_walk_start(&priv->vsp_iter);
 396         while ((h = rhashtable_walk_next(&priv->vsp_iter)) != NULL) {
 397                 struct inode *inode;
 398                 int nr;
 399
 400                 if (IS_ERR(h)) {
 401                         if (PTR_ERR(h) == -EAGAIN)
 402                                 continue;
 403                         break;
 404                 }
 405
 406                 if (!priv->vsp_clob) {
 407                         struct lu_object *lu_obj;
 408
 409                         lu_obj = lu_object_get_first(h, dev);
 410                         if (!lu_obj)
 411                                 continue;
 412
 413                         priv->vsp_clob = lu2cl(lu_obj);
 414                         lu_object_ref_add_atomic(lu_obj, "dump", current);
 415                         priv->vsp_page_index = 0;
 416                 }
 417
 418                 inode = vvp_object_inode(priv->vsp_clob);
 419                 nr = find_get_pages_contig(inode->i_mapping,
 420                                            priv->vsp_page_index, 1, &vmpage);
 421                 if (nr > 0) {
 422                         priv->vsp_page_index = vmpage->index;
 423                         break;
 424                 }
 425                 lu_object_ref_del(&priv->vsp_clob->co_lu, "dump", current);
 426                 cl_object_put(priv->vsp_env, priv->vsp_clob);
 427                 priv->vsp_clob = NULL;
 428                 priv->vsp_page_index = 0;
 429         }
 430         rhashtable_walk_stop(&priv->vsp_iter);
 431         return vmpage;
 432 }
 433
 434 #define seq_page_flag(seq, page, flag, has_flags) do {                  \
 435         if (test_bit(PG_##flag, &(page)->flags)) {                  \
 436                 seq_printf(seq, "%s"#flag, has_flags ? "|" : "");       \
 437                 has_flags = 1;                                          \
 438         }                                                               \
 439 } while(0)
 440
 441 static void vvp_pgcache_page_show(const struct lu_env *env,
 442                                   struct seq_file *seq, struct cl_page *page)
 443 {
 444         struct vvp_page *vpg;
 445         struct page      *vmpage;
 446         int              has_flags;
 447
 448         vpg = cl2vvp_page(cl_page_at(page, &vvp_device_type));
 449         vmpage = vpg->vpg_page;
 450         seq_printf(seq, " %5i | %p %p %s %s %s | %p "DFID"(%p) %lu %u [",
 451                    0 /* gen */,
 452                    vpg, page,
 453                    "none",
 454                    vpg->vpg_defer_uptodate ? "du" : "- ",
 455                    PageWriteback(vmpage) ? "wb" : "-",
 456                    vmpage,
 457                    PFID(ll_inode2fid(vmpage->mapping->host)),
 458                    vmpage->mapping->host, vmpage->index,
 459                    page_count(vmpage));
 460         has_flags = 0;
 461         seq_page_flag(seq, vmpage, locked, has_flags);
 462         seq_page_flag(seq, vmpage, error, has_flags);
 463         seq_page_flag(seq, vmpage, referenced, has_flags);
 464         seq_page_flag(seq, vmpage, uptodate, has_flags);
 465         seq_page_flag(seq, vmpage, dirty, has_flags);
 466         seq_page_flag(seq, vmpage, writeback, has_flags);
 467         seq_printf(seq, "%s]\n", has_flags ? "" : "-");
 468 }
 469
 470 static int vvp_pgcache_show(struct seq_file *f, void *v)
 471 {
 472         struct vvp_seq_private *priv = f->private;
 473         struct page *vmpage = v;
 474         struct cl_page *page;
 475
 476         seq_printf(f, "%8lx@" DFID ": ", vmpage->index,
 477                    PFID(lu_object_fid(&priv->vsp_clob->co_lu)));
 478         lock_page(vmpage);
 479         page = cl_vmpage_page(vmpage, priv->vsp_clob);
 480         unlock_page(vmpage);
 481         put_page(vmpage);
 482
 483         if (page) {
 484                 vvp_pgcache_page_show(priv->vsp_env, f, page);
 485                 cl_page_put(priv->vsp_env, page);
 486         } else {
 487                 seq_puts(f, "missing\n");
 488         }
 489
 490         return 0;
 491 }
 492
 493 static void vvp_pgcache_rewind(struct vvp_seq_private *priv)
 494 {
 495         if (priv->vvp_prev_pos) {
 496                 struct lu_site *s = priv->vsp_sbi->ll_cl->cd_lu_dev.ld_site;
 497
 498                 rhashtable_walk_exit(&priv->vsp_iter);
 499                 rhashtable_walk_enter(&s->ls_obj_hash, &priv->vsp_iter);
 500                 priv->vvp_prev_pos = 0;
 501                 if (priv->vsp_clob) {
 502                         lu_object_ref_del(&priv->vsp_clob->co_lu, "dump",
 503                                           current);
 504                         cl_object_put(priv->vsp_env, priv->vsp_clob);
 505                 }
 506                 priv->vsp_clob = NULL;
 507         }
 508 }
 509
 510 static struct page *vvp_pgcache_next_page(struct vvp_seq_private *priv)
 511 {
 512         priv->vsp_page_index += 1;
 513         return vvp_pgcache_current(priv);
 514 }
 515
 516 static void *vvp_pgcache_start(struct seq_file *f, loff_t *pos)
 517 {
 518         struct vvp_seq_private *priv = f->private;
 519
 520         if (*pos == 0) {
 521                 vvp_pgcache_rewind(priv);
 522         } else if (*pos == priv->vvp_prev_pos) {
 523                 /* Return the current item */;
 524         } else {
 525                 WARN_ON(*pos != priv->vvp_prev_pos + 1);
 526                 priv->vsp_page_index += 1;
 527         }
 528
 529         priv->vvp_prev_pos = *pos;
 530         return vvp_pgcache_current(priv);
 531 }
 532
 533 static void *vvp_pgcache_next(struct seq_file *f, void *v, loff_t *pos)
 534 {
 535         struct vvp_seq_private *priv = f->private;
 536
 537         WARN_ON(*pos != priv->vvp_prev_pos);
 538         *pos += 1;
 539         priv->vvp_prev_pos = *pos;
 540         return vvp_pgcache_next_page(priv);
 541 }
 542
 543 static void vvp_pgcache_stop(struct seq_file *f, void *v)
 544 {
 545         /* Nothing to do */
 546 }
 547
 548 static const struct seq_operations vvp_pgcache_ops = {
 549         .start = vvp_pgcache_start,
 550         .next  = vvp_pgcache_next,
 551         .stop  = vvp_pgcache_stop,
 552         .show  = vvp_pgcache_show
 553 };
 554
 555 static int vvp_dump_pgcache_seq_open(struct inode *inode, struct file *filp)
 556 {
 557         struct vvp_seq_private *priv;
 558         struct lu_site *s;
 559
 560         priv = __seq_open_private(filp, &vvp_pgcache_ops, sizeof(*priv));
 561         if (!priv)
 562                 return -ENOMEM;
 563
 564         priv->vsp_sbi = inode->i_private;
 565         priv->vsp_env = cl_env_get(&priv->vsp_refcheck);
 566         priv->vsp_clob = NULL;
 567         if (IS_ERR(priv->vsp_env)) {
 568                 int err = PTR_ERR(priv->vsp_env);
 569
 570                 seq_release_private(inode, filp);
 571                 return err;
 572         }
 573
 574         s = priv->vsp_sbi->ll_cl->cd_lu_dev.ld_site;
 575         rhashtable_walk_enter(&s->ls_obj_hash, &priv->vsp_iter);
 576
 577         return 0;
 578 }
 579
 580 static int vvp_dump_pgcache_seq_release(struct inode *inode, struct file *file)
 581 {
 582         struct seq_file *seq = file->private_data;
 583         struct vvp_seq_private *priv = seq->private;
 584
 585         if (priv->vsp_clob) {
 586                 lu_object_ref_del(&priv->vsp_clob->co_lu, "dump", current);
 587                 cl_object_put(priv->vsp_env, priv->vsp_clob);
 588         }
 589         cl_env_put(priv->vsp_env, &priv->vsp_refcheck);
 590         rhashtable_walk_exit(&priv->vsp_iter);
 591         return seq_release_private(inode, file);
 592 }
 593
 594 const struct file_operations vvp_dump_pgcache_file_ops = {
 595         .owner   = THIS_MODULE,
 596         .open    = vvp_dump_pgcache_seq_open,
 597         .read    = seq_read,
 598         .llseek  = seq_lseek,
 599         .release = vvp_dump_pgcache_seq_release,
 600 };