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[fs/lustre-release.git] / lustre / lov / lov_object.c
1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; If not, see
18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19  *
20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21  * CA 95054 USA or visit www.sun.com if you need additional information or
22  * have any questions.
23  *
24  * GPL HEADER END
25  */
26 /*
27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 2011, 2013, Intel Corporation.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  *
36  * Implementation of cl_object for LOV layer.
37  *
38  *   Author: Nikita Danilov <nikita.danilov@sun.com>
39  *   Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
40  */
41
42 #define DEBUG_SUBSYSTEM S_LOV
43
44 #include "lov_cl_internal.h"
45 #include <lustre_debug.h>
46
47 /** \addtogroup lov
48  *  @{
49  */
50
51 /*****************************************************************************
52  *
53  * Layout operations.
54  *
55  */
56
57 struct lov_layout_operations {
58         int (*llo_init)(const struct lu_env *env, struct lov_device *dev,
59                         struct lov_object *lov,
60                         const struct cl_object_conf *conf,
61                         union lov_layout_state *state);
62         int (*llo_delete)(const struct lu_env *env, struct lov_object *lov,
63                            union lov_layout_state *state);
64         void (*llo_fini)(const struct lu_env *env, struct lov_object *lov,
65                          union lov_layout_state *state);
66         void (*llo_install)(const struct lu_env *env, struct lov_object *lov,
67                             union lov_layout_state *state);
68         int  (*llo_print)(const struct lu_env *env, void *cookie,
69                           lu_printer_t p, const struct lu_object *o);
70         int  (*llo_page_init)(const struct lu_env *env, struct cl_object *obj,
71                                 struct cl_page *page, struct page *vmpage);
72         int  (*llo_lock_init)(const struct lu_env *env,
73                               struct cl_object *obj, struct cl_lock *lock,
74                               const struct cl_io *io);
75         int  (*llo_io_init)(const struct lu_env *env,
76                             struct cl_object *obj, struct cl_io *io);
77         int  (*llo_getattr)(const struct lu_env *env, struct cl_object *obj,
78                             struct cl_attr *attr);
79 };
80
81 static int lov_layout_wait(const struct lu_env *env, struct lov_object *lov);
82
83 /*****************************************************************************
84  *
85  * Lov object layout operations.
86  *
87  */
88
89 static void lov_install_empty(const struct lu_env *env,
90                               struct lov_object *lov,
91                               union  lov_layout_state *state)
92 {
93         /*
94          * File without objects.
95          */
96 }
97
98 static int lov_init_empty(const struct lu_env *env,
99                           struct lov_device *dev, struct lov_object *lov,
100                           const struct cl_object_conf *conf,
101                           union  lov_layout_state *state)
102 {
103         return 0;
104 }
105
106 static void lov_install_raid0(const struct lu_env *env,
107                               struct lov_object *lov,
108                               union  lov_layout_state *state)
109 {
110 }
111
112 static struct cl_object *lov_sub_find(const struct lu_env *env,
113                                       struct cl_device *dev,
114                                       const struct lu_fid *fid,
115                                       const struct cl_object_conf *conf)
116 {
117         struct lu_object *o;
118
119         ENTRY;
120         o = lu_object_find_at(env, cl2lu_dev(dev), fid, &conf->coc_lu);
121         LASSERT(ergo(!IS_ERR(o), o->lo_dev->ld_type == &lovsub_device_type));
122         RETURN(lu2cl(o));
123 }
124
125 static int lov_init_sub(const struct lu_env *env, struct lov_object *lov,
126                         struct cl_object *stripe, struct lov_layout_raid0 *r0,
127                         int idx)
128 {
129         struct cl_object_header *hdr;
130         struct cl_object_header *subhdr;
131         struct cl_object_header *parent;
132         struct lov_oinfo        *oinfo;
133         int result;
134
135         if (OBD_FAIL_CHECK(OBD_FAIL_LOV_INIT)) {
136                 /* For sanity:test_206.
137                  * Do not leave the object in cache to avoid accessing
138                  * freed memory. This is because osc_object is referring to
139                  * lov_oinfo of lsm_stripe_data which will be freed due to
140                  * this failure. */
141                 cl_object_kill(env, stripe);
142                 cl_object_put(env, stripe);
143                 return -EIO;
144         }
145
146         hdr    = cl_object_header(lov2cl(lov));
147         subhdr = cl_object_header(stripe);
148
149         oinfo = lov->lo_lsm->lsm_oinfo[idx];
150         CDEBUG(D_INODE, DFID"@%p[%d] -> "DFID"@%p: ostid: "DOSTID
151                " idx: %d gen: %d\n",
152                PFID(&subhdr->coh_lu.loh_fid), subhdr, idx,
153                PFID(&hdr->coh_lu.loh_fid), hdr, POSTID(&oinfo->loi_oi),
154                oinfo->loi_ost_idx, oinfo->loi_ost_gen);
155
156         /* reuse ->coh_attr_guard to protect coh_parent change */
157         spin_lock(&subhdr->coh_attr_guard);
158         parent = subhdr->coh_parent;
159         if (parent == NULL) {
160                 subhdr->coh_parent = hdr;
161                 spin_unlock(&subhdr->coh_attr_guard);
162                 subhdr->coh_nesting = hdr->coh_nesting + 1;
163                 lu_object_ref_add(&stripe->co_lu, "lov-parent", lov);
164                 r0->lo_sub[idx] = cl2lovsub(stripe);
165                 r0->lo_sub[idx]->lso_super = lov;
166                 r0->lo_sub[idx]->lso_index = idx;
167                 result = 0;
168         } else {
169                 struct lu_object  *old_obj;
170                 struct lov_object *old_lov;
171                 unsigned int mask = D_INODE;
172
173                 spin_unlock(&subhdr->coh_attr_guard);
174                 old_obj = lu_object_locate(&parent->coh_lu, &lov_device_type);
175                 LASSERT(old_obj != NULL);
176                 old_lov = cl2lov(lu2cl(old_obj));
177                 if (old_lov->lo_layout_invalid) {
178                         /* the object's layout has already changed but isn't
179                          * refreshed */
180                         lu_object_unhash(env, &stripe->co_lu);
181                         result = -EAGAIN;
182                 } else {
183                         mask = D_ERROR;
184                         result = -EIO;
185                 }
186
187                 LU_OBJECT_DEBUG(mask, env, &stripe->co_lu,
188                                 "stripe %d is already owned.\n", idx);
189                 LU_OBJECT_DEBUG(mask, env, old_obj, "owned.\n");
190                 LU_OBJECT_HEADER(mask, env, lov2lu(lov), "try to own.\n");
191                 cl_object_put(env, stripe);
192         }
193         return result;
194 }
195
196 static int lov_init_raid0(const struct lu_env *env,
197                           struct lov_device *dev, struct lov_object *lov,
198                           const struct cl_object_conf *conf,
199                           union  lov_layout_state *state)
200 {
201         int result;
202         int i;
203
204         struct cl_object        *stripe;
205         struct lov_thread_info  *lti     = lov_env_info(env);
206         struct cl_object_conf   *subconf = &lti->lti_stripe_conf;
207         struct lov_stripe_md    *lsm     = conf->u.coc_md->lsm;
208         struct lu_fid           *ofid    = &lti->lti_fid;
209         struct lov_layout_raid0 *r0      = &state->raid0;
210
211         ENTRY;
212
213         if (lsm->lsm_magic != LOV_MAGIC_V1 && lsm->lsm_magic != LOV_MAGIC_V3) {
214                 dump_lsm(D_ERROR, lsm);
215                 LASSERTF(0, "magic mismatch, expected %d/%d, actual %d.\n",
216                          LOV_MAGIC_V1, LOV_MAGIC_V3, lsm->lsm_magic);
217         }
218
219         LASSERT(lov->lo_lsm == NULL);
220         lov->lo_lsm = lsm_addref(lsm);
221         r0->lo_nr  = lsm->lsm_stripe_count;
222         LASSERT(r0->lo_nr <= lov_targets_nr(dev));
223
224         OBD_ALLOC_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
225         if (r0->lo_sub != NULL) {
226                 result = 0;
227                 subconf->coc_inode = conf->coc_inode;
228                 spin_lock_init(&r0->lo_sub_lock);
229                 /*
230                  * Create stripe cl_objects.
231                  */
232                 for (i = 0; i < r0->lo_nr && result == 0; ++i) {
233                         struct cl_device *subdev;
234                         struct lov_oinfo *oinfo = lsm->lsm_oinfo[i];
235                         int ost_idx = oinfo->loi_ost_idx;
236
237                         result = ostid_to_fid(ofid, &oinfo->loi_oi,
238                                               oinfo->loi_ost_idx);
239                         if (result != 0)
240                                 GOTO(out, result);
241
242                         subdev = lovsub2cl_dev(dev->ld_target[ost_idx]);
243                         subconf->u.coc_oinfo = oinfo;
244                         LASSERTF(subdev != NULL, "not init ost %d\n", ost_idx);
245                         /* In the function below, .hs_keycmp resolves to
246                          * lu_obj_hop_keycmp() */
247                         /* coverity[overrun-buffer-val] */
248                         stripe = lov_sub_find(env, subdev, ofid, subconf);
249                         if (!IS_ERR(stripe)) {
250                                 result = lov_init_sub(env, lov, stripe, r0, i);
251                                 if (result == -EAGAIN) { /* try again */
252                                         --i;
253                                         result = 0;
254                                 }
255                         } else {
256                                 result = PTR_ERR(stripe);
257                         }
258                 }
259         } else
260                 result = -ENOMEM;
261 out:
262         RETURN(result);
263 }
264
265 static int lov_init_released(const struct lu_env *env,
266                         struct lov_device *dev, struct lov_object *lov,
267                         const struct cl_object_conf *conf,
268                         union  lov_layout_state *state)
269 {
270         struct lov_stripe_md *lsm = conf->u.coc_md->lsm;
271
272         LASSERT(lsm != NULL);
273         LASSERT(lsm_is_released(lsm));
274         LASSERT(lov->lo_lsm == NULL);
275
276         lov->lo_lsm = lsm_addref(lsm);
277         return 0;
278 }
279
280 static int lov_delete_empty(const struct lu_env *env, struct lov_object *lov,
281                             union lov_layout_state *state)
282 {
283         LASSERT(lov->lo_type == LLT_EMPTY || lov->lo_type == LLT_RELEASED);
284
285         lov_layout_wait(env, lov);
286
287         cl_object_prune(env, &lov->lo_cl);
288         return 0;
289 }
290
291 static void lov_subobject_kill(const struct lu_env *env, struct lov_object *lov,
292                                struct lovsub_object *los, int idx)
293 {
294         struct cl_object        *sub;
295         struct lov_layout_raid0 *r0;
296         struct lu_site          *site;
297         struct lu_site_bkt_data *bkt;
298         wait_queue_t          *waiter;
299
300         r0  = &lov->u.raid0;
301         LASSERT(r0->lo_sub[idx] == los);
302
303         sub  = lovsub2cl(los);
304         site = sub->co_lu.lo_dev->ld_site;
305         bkt  = lu_site_bkt_from_fid(site, &sub->co_lu.lo_header->loh_fid);
306
307         cl_object_kill(env, sub);
308         /* release a reference to the sub-object and ... */
309         lu_object_ref_del(&sub->co_lu, "lov-parent", lov);
310         cl_object_put(env, sub);
311
312         /* ... wait until it is actually destroyed---sub-object clears its
313          * ->lo_sub[] slot in lovsub_object_fini() */
314         if (r0->lo_sub[idx] == los) {
315                 waiter = &lov_env_info(env)->lti_waiter;
316                 init_waitqueue_entry_current(waiter);
317                 add_wait_queue(&bkt->lsb_marche_funebre, waiter);
318                 set_current_state(TASK_UNINTERRUPTIBLE);
319                 while (1) {
320                         /* this wait-queue is signaled at the end of
321                          * lu_object_free(). */
322                         set_current_state(TASK_UNINTERRUPTIBLE);
323                         spin_lock(&r0->lo_sub_lock);
324                         if (r0->lo_sub[idx] == los) {
325                                 spin_unlock(&r0->lo_sub_lock);
326                                 waitq_wait(waiter, TASK_UNINTERRUPTIBLE);
327                         } else {
328                                 spin_unlock(&r0->lo_sub_lock);
329                                 set_current_state(TASK_RUNNING);
330                                 break;
331                         }
332                 }
333                 remove_wait_queue(&bkt->lsb_marche_funebre, waiter);
334         }
335         LASSERT(r0->lo_sub[idx] == NULL);
336 }
337
338 static int lov_delete_raid0(const struct lu_env *env, struct lov_object *lov,
339                             union lov_layout_state *state)
340 {
341         struct lov_layout_raid0 *r0 = &state->raid0;
342         struct lov_stripe_md    *lsm = lov->lo_lsm;
343         int i;
344
345         ENTRY;
346
347         dump_lsm(D_INODE, lsm);
348
349         lov_layout_wait(env, lov);
350         if (r0->lo_sub != NULL) {
351                 for (i = 0; i < r0->lo_nr; ++i) {
352                         struct lovsub_object *los = r0->lo_sub[i];
353
354                         if (los != NULL) {
355                                 cl_locks_prune(env, &los->lso_cl, 1);
356                                 /*
357                                  * If top-level object is to be evicted from
358                                  * the cache, so are its sub-objects.
359                                  */
360                                 lov_subobject_kill(env, lov, los, i);
361                         }
362                 }
363         }
364         cl_object_prune(env, &lov->lo_cl);
365         RETURN(0);
366 }
367
368 static void lov_fini_empty(const struct lu_env *env, struct lov_object *lov,
369                            union lov_layout_state *state)
370 {
371         LASSERT(lov->lo_type == LLT_EMPTY || lov->lo_type == LLT_RELEASED);
372 }
373
374 static void lov_fini_raid0(const struct lu_env *env, struct lov_object *lov,
375                            union lov_layout_state *state)
376 {
377         struct lov_layout_raid0 *r0 = &state->raid0;
378         ENTRY;
379
380         if (r0->lo_sub != NULL) {
381                 OBD_FREE_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
382                 r0->lo_sub = NULL;
383         }
384
385         dump_lsm(D_INODE, lov->lo_lsm);
386         lov_free_memmd(&lov->lo_lsm);
387
388         EXIT;
389 }
390
391 static void lov_fini_released(const struct lu_env *env, struct lov_object *lov,
392                                 union lov_layout_state *state)
393 {
394         ENTRY;
395         dump_lsm(D_INODE, lov->lo_lsm);
396         lov_free_memmd(&lov->lo_lsm);
397         EXIT;
398 }
399
400 static int lov_print_empty(const struct lu_env *env, void *cookie,
401                            lu_printer_t p, const struct lu_object *o)
402 {
403         (*p)(env, cookie, "empty %d\n", lu2lov(o)->lo_layout_invalid);
404         return 0;
405 }
406
407 static int lov_print_raid0(const struct lu_env *env, void *cookie,
408                            lu_printer_t p, const struct lu_object *o)
409 {
410         struct lov_object       *lov = lu2lov(o);
411         struct lov_layout_raid0 *r0  = lov_r0(lov);
412         struct lov_stripe_md    *lsm = lov->lo_lsm;
413         int                      i;
414
415         (*p)(env, cookie, "stripes: %d, %s, lsm{%p 0x%08X %d %u %u}:\n",
416                 r0->lo_nr, lov->lo_layout_invalid ? "invalid" : "valid", lsm,
417                 lsm->lsm_magic, cfs_atomic_read(&lsm->lsm_refc),
418                 lsm->lsm_stripe_count, lsm->lsm_layout_gen);
419         for (i = 0; i < r0->lo_nr; ++i) {
420                 struct lu_object *sub;
421
422                 if (r0->lo_sub[i] != NULL) {
423                         sub = lovsub2lu(r0->lo_sub[i]);
424                         lu_object_print(env, cookie, p, sub);
425                 } else {
426                         (*p)(env, cookie, "sub %d absent\n", i);
427                 }
428         }
429         return 0;
430 }
431
432 static int lov_print_released(const struct lu_env *env, void *cookie,
433                                 lu_printer_t p, const struct lu_object *o)
434 {
435         struct lov_object       *lov = lu2lov(o);
436         struct lov_stripe_md    *lsm = lov->lo_lsm;
437
438         (*p)(env, cookie,
439                 "released: %s, lsm{%p 0x%08X %d %u %u}:\n",
440                 lov->lo_layout_invalid ? "invalid" : "valid", lsm,
441                 lsm->lsm_magic, cfs_atomic_read(&lsm->lsm_refc),
442                 lsm->lsm_stripe_count, lsm->lsm_layout_gen);
443         return 0;
444 }
445
446 /**
447  * Implements cl_object_operations::coo_attr_get() method for an object
448  * without stripes (LLT_EMPTY layout type).
449  *
450  * The only attributes this layer is authoritative in this case is
451  * cl_attr::cat_blocks---it's 0.
452  */
453 static int lov_attr_get_empty(const struct lu_env *env, struct cl_object *obj,
454                               struct cl_attr *attr)
455 {
456         attr->cat_blocks = 0;
457         return 0;
458 }
459
460 static int lov_attr_get_raid0(const struct lu_env *env, struct cl_object *obj,
461                               struct cl_attr *attr)
462 {
463         struct lov_object       *lov = cl2lov(obj);
464         struct lov_layout_raid0 *r0 = lov_r0(lov);
465         struct cl_attr          *lov_attr = &r0->lo_attr;
466         int                      result = 0;
467
468         ENTRY;
469
470         /* this is called w/o holding type guard mutex, so it must be inside
471          * an on going IO otherwise lsm may be replaced.
472          * LU-2117: it turns out there exists one exception. For mmaped files,
473          * the lock of those files may be requested in the other file's IO
474          * context, and this function is called in ccc_lock_state(), it will
475          * hit this assertion.
476          * Anyway, it's still okay to call attr_get w/o type guard as layout
477          * can't go if locks exist. */
478         /* LASSERT(cfs_atomic_read(&lsm->lsm_refc) > 1); */
479
480         if (!r0->lo_attr_valid) {
481                 struct lov_stripe_md    *lsm = lov->lo_lsm;
482                 struct ost_lvb          *lvb = &lov_env_info(env)->lti_lvb;
483                 __u64                    kms = 0;
484
485                 memset(lvb, 0, sizeof(*lvb));
486                 /* XXX: timestamps can be negative by sanity:test_39m,
487                  * how can it be? */
488                 lvb->lvb_atime = LLONG_MIN;
489                 lvb->lvb_ctime = LLONG_MIN;
490                 lvb->lvb_mtime = LLONG_MIN;
491
492                 /*
493                  * XXX that should be replaced with a loop over sub-objects,
494                  * doing cl_object_attr_get() on them. But for now, let's
495                  * reuse old lov code.
496                  */
497
498                 /*
499                  * XXX take lsm spin-lock to keep lov_merge_lvb_kms()
500                  * happy. It's not needed, because new code uses
501                  * ->coh_attr_guard spin-lock to protect consistency of
502                  * sub-object attributes.
503                  */
504                 lov_stripe_lock(lsm);
505                 result = lov_merge_lvb_kms(lsm, lvb, &kms);
506                 lov_stripe_unlock(lsm);
507                 if (result == 0) {
508                         cl_lvb2attr(lov_attr, lvb);
509                         lov_attr->cat_kms = kms;
510                         r0->lo_attr_valid = 1;
511                 }
512         }
513         if (result == 0) { /* merge results */
514                 attr->cat_blocks = lov_attr->cat_blocks;
515                 attr->cat_size = lov_attr->cat_size;
516                 attr->cat_kms = lov_attr->cat_kms;
517                 if (attr->cat_atime < lov_attr->cat_atime)
518                         attr->cat_atime = lov_attr->cat_atime;
519                 if (attr->cat_ctime < lov_attr->cat_ctime)
520                         attr->cat_ctime = lov_attr->cat_ctime;
521                 if (attr->cat_mtime < lov_attr->cat_mtime)
522                         attr->cat_mtime = lov_attr->cat_mtime;
523         }
524         RETURN(result);
525 }
526
527 const static struct lov_layout_operations lov_dispatch[] = {
528         [LLT_EMPTY] = {
529                 .llo_init      = lov_init_empty,
530                 .llo_delete    = lov_delete_empty,
531                 .llo_fini      = lov_fini_empty,
532                 .llo_install   = lov_install_empty,
533                 .llo_print     = lov_print_empty,
534                 .llo_page_init = lov_page_init_empty,
535                 .llo_lock_init = lov_lock_init_empty,
536                 .llo_io_init   = lov_io_init_empty,
537                 .llo_getattr   = lov_attr_get_empty
538         },
539         [LLT_RAID0] = {
540                 .llo_init      = lov_init_raid0,
541                 .llo_delete    = lov_delete_raid0,
542                 .llo_fini      = lov_fini_raid0,
543                 .llo_install   = lov_install_raid0,
544                 .llo_print     = lov_print_raid0,
545                 .llo_page_init = lov_page_init_raid0,
546                 .llo_lock_init = lov_lock_init_raid0,
547                 .llo_io_init   = lov_io_init_raid0,
548                 .llo_getattr   = lov_attr_get_raid0
549         },
550         [LLT_RELEASED] = {
551                 .llo_init      = lov_init_released,
552                 .llo_delete    = lov_delete_empty,
553                 .llo_fini      = lov_fini_released,
554                 .llo_install   = lov_install_empty,
555                 .llo_print     = lov_print_released,
556                 .llo_page_init = lov_page_init_empty,
557                 .llo_lock_init = lov_lock_init_empty,
558                 .llo_io_init   = lov_io_init_released,
559                 .llo_getattr   = lov_attr_get_empty
560         }
561 };
562
563 /**
564  * Performs a double-dispatch based on the layout type of an object.
565  */
566 #define LOV_2DISPATCH_NOLOCK(obj, op, ...)                              \
567 ({                                                                      \
568         struct lov_object                      *__obj = (obj);          \
569         enum lov_layout_type                    __llt;                  \
570                                                                         \
571         __llt = __obj->lo_type;                                         \
572         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
573         lov_dispatch[__llt].op(__VA_ARGS__);                            \
574 })
575
576 /**
577  * Return lov_layout_type associated with a given lsm
578  */
579 enum lov_layout_type lov_type(struct lov_stripe_md *lsm)
580 {
581         if (lsm == NULL)
582                 return LLT_EMPTY;
583         if (lsm_is_released(lsm))
584                 return LLT_RELEASED;
585         return LLT_RAID0;
586 }
587
588 static inline void lov_conf_freeze(struct lov_object *lov)
589 {
590         if (lov->lo_owner != cfs_current())
591                 down_read(&lov->lo_type_guard);
592 }
593
594 static inline void lov_conf_thaw(struct lov_object *lov)
595 {
596         if (lov->lo_owner != cfs_current())
597                 up_read(&lov->lo_type_guard);
598 }
599
600 #define LOV_2DISPATCH_MAYLOCK(obj, op, lock, ...)                       \
601 ({                                                                      \
602         struct lov_object                      *__obj = (obj);          \
603         int                                     __lock = !!(lock);      \
604         typeof(lov_dispatch[0].op(__VA_ARGS__)) __result;               \
605                                                                         \
606         if (__lock)                                                     \
607                 lov_conf_freeze(__obj);                                 \
608         __result = LOV_2DISPATCH_NOLOCK(obj, op, __VA_ARGS__);          \
609         if (__lock)                                                     \
610                 lov_conf_thaw(__obj);                                   \
611         __result;                                                       \
612 })
613
614 /**
615  * Performs a locked double-dispatch based on the layout type of an object.
616  */
617 #define LOV_2DISPATCH(obj, op, ...)                     \
618         LOV_2DISPATCH_MAYLOCK(obj, op, 1, __VA_ARGS__)
619
620 #define LOV_2DISPATCH_VOID(obj, op, ...)                                \
621 do {                                                                    \
622         struct lov_object                      *__obj = (obj);          \
623         enum lov_layout_type                    __llt;                  \
624                                                                         \
625         lov_conf_freeze(__obj);                                         \
626         __llt = __obj->lo_type;                                         \
627         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
628         lov_dispatch[__llt].op(__VA_ARGS__);                            \
629         lov_conf_thaw(__obj);                                           \
630 } while (0)
631
632 static void lov_conf_lock(struct lov_object *lov)
633 {
634         LASSERT(lov->lo_owner != cfs_current());
635         down_write(&lov->lo_type_guard);
636         LASSERT(lov->lo_owner == NULL);
637         lov->lo_owner = cfs_current();
638 }
639
640 static void lov_conf_unlock(struct lov_object *lov)
641 {
642         lov->lo_owner = NULL;
643         up_write(&lov->lo_type_guard);
644 }
645
646 static int lov_layout_wait(const struct lu_env *env, struct lov_object *lov)
647 {
648         struct l_wait_info lwi = { 0 };
649         ENTRY;
650
651         while (cfs_atomic_read(&lov->lo_active_ios) > 0) {
652                 CDEBUG(D_INODE, "file:"DFID" wait for active IO, now: %d.\n",
653                         PFID(lu_object_fid(lov2lu(lov))),
654                         cfs_atomic_read(&lov->lo_active_ios));
655
656                 l_wait_event(lov->lo_waitq,
657                              cfs_atomic_read(&lov->lo_active_ios) == 0, &lwi);
658         }
659         RETURN(0);
660 }
661
662 static int lov_layout_change(const struct lu_env *unused,
663                              struct lov_object *lov,
664                              const struct cl_object_conf *conf)
665 {
666         int result;
667         enum lov_layout_type llt = LLT_EMPTY;
668         union lov_layout_state *state = &lov->u;
669         const struct lov_layout_operations *old_ops;
670         const struct lov_layout_operations *new_ops;
671
672         struct cl_object_header *hdr = cl_object_header(&lov->lo_cl);
673         void *cookie;
674         struct lu_env *env;
675         int refcheck;
676         ENTRY;
677
678         LASSERT(0 <= lov->lo_type && lov->lo_type < ARRAY_SIZE(lov_dispatch));
679
680         if (conf->u.coc_md != NULL)
681                 llt = lov_type(conf->u.coc_md->lsm);
682         LASSERT(0 <= llt && llt < ARRAY_SIZE(lov_dispatch));
683
684         cookie = cl_env_reenter();
685         env = cl_env_get(&refcheck);
686         if (IS_ERR(env)) {
687                 cl_env_reexit(cookie);
688                 RETURN(PTR_ERR(env));
689         }
690
691         CDEBUG(D_INODE, DFID" from %s to %s\n",
692                PFID(lu_object_fid(lov2lu(lov))),
693                llt2str(lov->lo_type), llt2str(llt));
694
695         old_ops = &lov_dispatch[lov->lo_type];
696         new_ops = &lov_dispatch[llt];
697
698         result = old_ops->llo_delete(env, lov, &lov->u);
699         if (result == 0) {
700                 old_ops->llo_fini(env, lov, &lov->u);
701
702                 LASSERT(cfs_atomic_read(&lov->lo_active_ios) == 0);
703                 LASSERT(hdr->coh_tree.rnode == NULL);
704                 LASSERT(hdr->coh_pages == 0);
705
706                 lov->lo_type = LLT_EMPTY;
707                 result = new_ops->llo_init(env,
708                                         lu2lov_dev(lov->lo_cl.co_lu.lo_dev),
709                                         lov, conf, state);
710                 if (result == 0) {
711                         new_ops->llo_install(env, lov, state);
712                         lov->lo_type = llt;
713                 } else {
714                         new_ops->llo_delete(env, lov, state);
715                         new_ops->llo_fini(env, lov, state);
716                         /* this file becomes an EMPTY file. */
717                 }
718         }
719
720         cl_env_put(env, &refcheck);
721         cl_env_reexit(cookie);
722         RETURN(result);
723 }
724
725 /*****************************************************************************
726  *
727  * Lov object operations.
728  *
729  */
730 int lov_object_init(const struct lu_env *env, struct lu_object *obj,
731                     const struct lu_object_conf *conf)
732 {
733         struct lov_device            *dev   = lu2lov_dev(obj->lo_dev);
734         struct lov_object            *lov   = lu2lov(obj);
735         const struct cl_object_conf  *cconf = lu2cl_conf(conf);
736         union  lov_layout_state      *set   = &lov->u;
737         const struct lov_layout_operations *ops;
738         int result;
739
740         ENTRY;
741         init_rwsem(&lov->lo_type_guard);
742         cfs_atomic_set(&lov->lo_active_ios, 0);
743         init_waitqueue_head(&lov->lo_waitq);
744
745         cl_object_page_init(lu2cl(obj), sizeof(struct lov_page));
746
747         /* no locking is necessary, as object is being created */
748         lov->lo_type = lov_type(cconf->u.coc_md->lsm);
749         ops = &lov_dispatch[lov->lo_type];
750         result = ops->llo_init(env, dev, lov, cconf, set);
751         if (result == 0)
752                 ops->llo_install(env, lov, set);
753         RETURN(result);
754 }
755
756 static int lov_conf_set(const struct lu_env *env, struct cl_object *obj,
757                         const struct cl_object_conf *conf)
758 {
759         struct lov_stripe_md    *lsm = NULL;
760         struct lov_object       *lov = cl2lov(obj);
761         int                      result = 0;
762         ENTRY;
763
764         lov_conf_lock(lov);
765         if (conf->coc_opc == OBJECT_CONF_INVALIDATE) {
766                 lov->lo_layout_invalid = true;
767                 GOTO(out, result = 0);
768         }
769
770         if (conf->coc_opc == OBJECT_CONF_WAIT) {
771                 if (lov->lo_layout_invalid &&
772                     cfs_atomic_read(&lov->lo_active_ios) > 0) {
773                         lov_conf_unlock(lov);
774                         result = lov_layout_wait(env, lov);
775                         lov_conf_lock(lov);
776                 }
777                 GOTO(out, result);
778         }
779
780         LASSERT(conf->coc_opc == OBJECT_CONF_SET);
781
782         if (conf->u.coc_md != NULL)
783                 lsm = conf->u.coc_md->lsm;
784         if ((lsm == NULL && lov->lo_lsm == NULL) ||
785             ((lsm != NULL && lov->lo_lsm != NULL) &&
786              (lov->lo_lsm->lsm_layout_gen == lsm->lsm_layout_gen) &&
787              (lov->lo_lsm->lsm_pattern == lsm->lsm_pattern))) {
788                 /* same version of layout */
789                 lov->lo_layout_invalid = false;
790                 GOTO(out, result = 0);
791         }
792
793         /* will change layout - check if there still exists active IO. */
794         if (cfs_atomic_read(&lov->lo_active_ios) > 0) {
795                 lov->lo_layout_invalid = true;
796                 GOTO(out, result = -EBUSY);
797         }
798
799         lov->lo_layout_invalid = lov_layout_change(env, lov, conf);
800         EXIT;
801
802 out:
803         lov_conf_unlock(lov);
804         CDEBUG(D_INODE, DFID" lo_layout_invalid=%d\n",
805                PFID(lu_object_fid(lov2lu(lov))), lov->lo_layout_invalid);
806         RETURN(result);
807 }
808
809 static void lov_object_delete(const struct lu_env *env, struct lu_object *obj)
810 {
811         struct lov_object *lov = lu2lov(obj);
812
813         ENTRY;
814         LOV_2DISPATCH_VOID(lov, llo_delete, env, lov, &lov->u);
815         EXIT;
816 }
817
818 static void lov_object_free(const struct lu_env *env, struct lu_object *obj)
819 {
820         struct lov_object *lov = lu2lov(obj);
821
822         ENTRY;
823         LOV_2DISPATCH_VOID(lov, llo_fini, env, lov, &lov->u);
824         lu_object_fini(obj);
825         OBD_SLAB_FREE_PTR(lov, lov_object_kmem);
826         EXIT;
827 }
828
829 static int lov_object_print(const struct lu_env *env, void *cookie,
830                             lu_printer_t p, const struct lu_object *o)
831 {
832         return LOV_2DISPATCH_NOLOCK(lu2lov(o), llo_print, env, cookie, p, o);
833 }
834
835 int lov_page_init(const struct lu_env *env, struct cl_object *obj,
836                   struct cl_page *page, struct page *vmpage)
837 {
838         return LOV_2DISPATCH_NOLOCK(cl2lov(obj),
839                                     llo_page_init, env, obj, page, vmpage);
840 }
841
842 /**
843  * Implements cl_object_operations::clo_io_init() method for lov
844  * layer. Dispatches to the appropriate layout io initialization method.
845  */
846 int lov_io_init(const struct lu_env *env, struct cl_object *obj,
847                 struct cl_io *io)
848 {
849         CL_IO_SLICE_CLEAN(lov_env_io(env), lis_cl);
850         return LOV_2DISPATCH_MAYLOCK(cl2lov(obj), llo_io_init,
851                                      !io->ci_ignore_layout, env, obj, io);
852 }
853
854 /**
855  * An implementation of cl_object_operations::clo_attr_get() method for lov
856  * layer. For raid0 layout this collects and merges attributes of all
857  * sub-objects.
858  */
859 static int lov_attr_get(const struct lu_env *env, struct cl_object *obj,
860                         struct cl_attr *attr)
861 {
862         /* do not take lock, as this function is called under a
863          * spin-lock. Layout is protected from changing by ongoing IO. */
864         return LOV_2DISPATCH_NOLOCK(cl2lov(obj), llo_getattr, env, obj, attr);
865 }
866
867 static int lov_attr_set(const struct lu_env *env, struct cl_object *obj,
868                         const struct cl_attr *attr, unsigned valid)
869 {
870         /*
871          * No dispatch is required here, as no layout implements this.
872          */
873         return 0;
874 }
875
876 int lov_lock_init(const struct lu_env *env, struct cl_object *obj,
877                   struct cl_lock *lock, const struct cl_io *io)
878 {
879         /* No need to lock because we've taken one refcount of layout.  */
880         return LOV_2DISPATCH_NOLOCK(cl2lov(obj), llo_lock_init, env, obj, lock,
881                                     io);
882 }
883
884 static const struct cl_object_operations lov_ops = {
885         .coo_page_init = lov_page_init,
886         .coo_lock_init = lov_lock_init,
887         .coo_io_init   = lov_io_init,
888         .coo_attr_get  = lov_attr_get,
889         .coo_attr_set  = lov_attr_set,
890         .coo_conf_set  = lov_conf_set
891 };
892
893 static const struct lu_object_operations lov_lu_obj_ops = {
894         .loo_object_init      = lov_object_init,
895         .loo_object_delete    = lov_object_delete,
896         .loo_object_release   = NULL,
897         .loo_object_free      = lov_object_free,
898         .loo_object_print     = lov_object_print,
899         .loo_object_invariant = NULL
900 };
901
902 struct lu_object *lov_object_alloc(const struct lu_env *env,
903                                    const struct lu_object_header *unused,
904                                    struct lu_device *dev)
905 {
906         struct lov_object *lov;
907         struct lu_object  *obj;
908
909         ENTRY;
910         OBD_SLAB_ALLOC_PTR_GFP(lov, lov_object_kmem, __GFP_IO);
911         if (lov != NULL) {
912                 obj = lov2lu(lov);
913                 lu_object_init(obj, NULL, dev);
914                 lov->lo_cl.co_ops = &lov_ops;
915                 lov->lo_type = -1; /* invalid, to catch uninitialized type */
916                 /*
917                  * object io operation vector (cl_object::co_iop) is installed
918                  * later in lov_object_init(), as different vectors are used
919                  * for object with different layouts.
920                  */
921                 obj->lo_ops = &lov_lu_obj_ops;
922         } else
923                 obj = NULL;
924         RETURN(obj);
925 }
926
927 struct lov_stripe_md *lov_lsm_addref(struct lov_object *lov)
928 {
929         struct lov_stripe_md *lsm = NULL;
930
931         lov_conf_freeze(lov);
932         if (lov->lo_lsm != NULL) {
933                 lsm = lsm_addref(lov->lo_lsm);
934                 CDEBUG(D_INODE, "lsm %p addref %d/%d by %p.\n",
935                         lsm, cfs_atomic_read(&lsm->lsm_refc),
936                         lov->lo_layout_invalid, cfs_current());
937         }
938         lov_conf_thaw(lov);
939         return lsm;
940 }
941
942 void lov_lsm_decref(struct lov_object *lov, struct lov_stripe_md *lsm)
943 {
944         if (lsm == NULL)
945                 return;
946
947         CDEBUG(D_INODE, "lsm %p decref %d by %p.\n",
948                 lsm, cfs_atomic_read(&lsm->lsm_refc), cfs_current());
949
950         lov_free_memmd(&lsm);
951 }
952
953 struct lov_stripe_md *lov_lsm_get(struct cl_object *clobj)
954 {
955         struct lu_object *luobj;
956         struct lov_stripe_md *lsm = NULL;
957
958         if (clobj == NULL)
959                 return NULL;
960
961         luobj = lu_object_locate(&cl_object_header(clobj)->coh_lu,
962                                  &lov_device_type);
963         if (luobj != NULL)
964                 lsm = lov_lsm_addref(lu2lov(luobj));
965         return lsm;
966 }
967 EXPORT_SYMBOL(lov_lsm_get);
968
969 void lov_lsm_put(struct cl_object *unused, struct lov_stripe_md *lsm)
970 {
971         if (lsm != NULL)
972                 lov_free_memmd(&lsm);
973 }
974 EXPORT_SYMBOL(lov_lsm_put);
975
976 int lov_read_and_clear_async_rc(struct cl_object *clob)
977 {
978         struct lu_object *luobj;
979         int rc = 0;
980         ENTRY;
981
982         luobj = lu_object_locate(&cl_object_header(clob)->coh_lu,
983                                  &lov_device_type);
984         if (luobj != NULL) {
985                 struct lov_object *lov = lu2lov(luobj);
986
987                 lov_conf_freeze(lov);
988                 switch (lov->lo_type) {
989                 case LLT_RAID0: {
990                         struct lov_stripe_md *lsm;
991                         int i;
992
993                         lsm = lov->lo_lsm;
994                         LASSERT(lsm != NULL);
995                         for (i = 0; i < lsm->lsm_stripe_count; i++) {
996                                 struct lov_oinfo *loi = lsm->lsm_oinfo[i];
997                                 if (loi->loi_ar.ar_rc && !rc)
998                                         rc = loi->loi_ar.ar_rc;
999                                 loi->loi_ar.ar_rc = 0;
1000                         }
1001                 }
1002                 case LLT_RELEASED:
1003                 case LLT_EMPTY:
1004                         break;
1005                 default:
1006                         LBUG();
1007                 }
1008                 lov_conf_thaw(lov);
1009         }
1010         RETURN(rc);
1011 }
1012 EXPORT_SYMBOL(lov_read_and_clear_async_rc);
1013
1014 /** @} lov */