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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, 2012, Intel Corporation.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  *
36  * 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, cfs_page_t *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,
127                         struct lov_layout_raid0 *r0, 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         parent = subhdr->coh_parent;
149
150         oinfo = lov->lo_lsm->lsm_oinfo[idx];
151         CDEBUG(D_INODE, DFID"@%p[%d] -> "DFID"@%p: ostid: "DOSTID
152                " idx: %d gen: %d\n",
153                PFID(&subhdr->coh_lu.loh_fid), subhdr, idx,
154                PFID(&hdr->coh_lu.loh_fid), hdr, POSTID(&oinfo->loi_oi),
155                oinfo->loi_ost_idx, oinfo->loi_ost_gen);
156
157         if (parent == NULL) {
158                 subhdr->coh_parent = hdr;
159                 subhdr->coh_nesting = hdr->coh_nesting + 1;
160                 lu_object_ref_add(&stripe->co_lu, "lov-parent", lov);
161                 r0->lo_sub[idx] = cl2lovsub(stripe);
162                 r0->lo_sub[idx]->lso_super = lov;
163                 r0->lo_sub[idx]->lso_index = idx;
164                 result = 0;
165         } else {
166                 struct lu_object  *old_obj;
167                 struct lov_object *old_lov;
168                 unsigned int mask = D_INODE;
169
170                 old_obj = lu_object_locate(&parent->coh_lu, &lov_device_type);
171                 LASSERT(old_obj != NULL);
172                 old_lov = cl2lov(lu2cl(old_obj));
173                 if (old_lov->lo_layout_invalid) {
174                         /* the object's layout has already changed but isn't
175                          * refreshed */
176                         lu_object_unhash(env, &stripe->co_lu);
177                         result = -EAGAIN;
178                 } else {
179                         mask = D_ERROR;
180                         result = -EIO;
181                 }
182
183                 LU_OBJECT_DEBUG(mask, env, &stripe->co_lu,
184                                 "stripe %d is already owned.\n", idx);
185                 LU_OBJECT_DEBUG(mask, env, old_obj, "owned.\n");
186                 LU_OBJECT_HEADER(mask, env, lov2lu(lov), "try to own.\n");
187                 cl_object_put(env, stripe);
188         }
189         return result;
190 }
191
192 static int lov_init_raid0(const struct lu_env *env,
193                           struct lov_device *dev, struct lov_object *lov,
194                           const struct cl_object_conf *conf,
195                           union  lov_layout_state *state)
196 {
197         int result;
198         int i;
199
200         struct cl_object        *stripe;
201         struct lov_thread_info  *lti     = lov_env_info(env);
202         struct cl_object_conf   *subconf = &lti->lti_stripe_conf;
203         struct lov_stripe_md    *lsm     = conf->u.coc_md->lsm;
204         struct lu_fid           *ofid    = &lti->lti_fid;
205         struct lov_layout_raid0 *r0      = &state->raid0;
206
207         ENTRY;
208
209         if (lsm->lsm_magic != LOV_MAGIC_V1 && lsm->lsm_magic != LOV_MAGIC_V3) {
210                 dump_lsm(D_ERROR, lsm);
211                 LASSERTF(0, "magic mismatch, expected %d/%d, actual %d.\n",
212                          LOV_MAGIC_V1, LOV_MAGIC_V3, lsm->lsm_magic);
213         }
214
215         LASSERT(lov->lo_lsm == NULL);
216         lov->lo_lsm = lsm_addref(lsm);
217         r0->lo_nr  = lsm->lsm_stripe_count;
218         LASSERT(r0->lo_nr <= lov_targets_nr(dev));
219
220         OBD_ALLOC_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
221         if (r0->lo_sub != NULL) {
222                 result = 0;
223                 subconf->coc_inode = conf->coc_inode;
224                 spin_lock_init(&r0->lo_sub_lock);
225                 /*
226                  * Create stripe cl_objects.
227                  */
228                 for (i = 0; i < r0->lo_nr && result == 0; ++i) {
229                         struct cl_device *subdev;
230                         struct lov_oinfo *oinfo = lsm->lsm_oinfo[i];
231                         int ost_idx = oinfo->loi_ost_idx;
232
233                         ostid_to_fid(ofid, &oinfo->loi_oi, oinfo->loi_ost_idx);
234                         subdev = lovsub2cl_dev(dev->ld_target[ost_idx]);
235                         subconf->u.coc_oinfo = oinfo;
236                         LASSERTF(subdev != NULL, "not init ost %d\n", ost_idx);
237                         /* In the function below, .hs_keycmp resolves to
238                          * lu_obj_hop_keycmp() */
239                         /* coverity[overrun-buffer-val] */
240                         stripe = lov_sub_find(env, subdev, ofid, subconf);
241                         if (!IS_ERR(stripe)) {
242                                 result = lov_init_sub(env, lov, stripe, r0, i);
243                                 if (result == -EAGAIN) { /* try again */
244                                         --i;
245                                         result = 0;
246                                 }
247                         } else {
248                                 result = PTR_ERR(stripe);
249                         }
250                 }
251         } else
252                 result = -ENOMEM;
253         RETURN(result);
254 }
255
256 static int lov_delete_empty(const struct lu_env *env, struct lov_object *lov,
257                             union lov_layout_state *state)
258 {
259         LASSERT(lov->lo_type == LLT_EMPTY);
260
261         lov_layout_wait(env, lov);
262
263         cl_object_prune(env, &lov->lo_cl);
264         return 0;
265 }
266
267 static void lov_subobject_kill(const struct lu_env *env, struct lov_object *lov,
268                                struct lovsub_object *los, int idx)
269 {
270         struct cl_object        *sub;
271         struct lov_layout_raid0 *r0;
272         struct lu_site          *site;
273         struct lu_site_bkt_data *bkt;
274         cfs_waitlink_t          *waiter;
275
276         r0  = &lov->u.raid0;
277         LASSERT(r0->lo_sub[idx] == los);
278
279         sub  = lovsub2cl(los);
280         site = sub->co_lu.lo_dev->ld_site;
281         bkt  = lu_site_bkt_from_fid(site, &sub->co_lu.lo_header->loh_fid);
282
283         cl_object_kill(env, sub);
284         /* release a reference to the sub-object and ... */
285         lu_object_ref_del(&sub->co_lu, "lov-parent", lov);
286         cl_object_put(env, sub);
287
288         /* ... wait until it is actually destroyed---sub-object clears its
289          * ->lo_sub[] slot in lovsub_object_fini() */
290         if (r0->lo_sub[idx] == los) {
291                 waiter = &lov_env_info(env)->lti_waiter;
292                 cfs_waitlink_init(waiter);
293                 cfs_waitq_add(&bkt->lsb_marche_funebre, waiter);
294                 cfs_set_current_state(CFS_TASK_UNINT);
295                 while (1) {
296                         /* this wait-queue is signaled at the end of
297                          * lu_object_free(). */
298                         cfs_set_current_state(CFS_TASK_UNINT);
299                         spin_lock(&r0->lo_sub_lock);
300                         if (r0->lo_sub[idx] == los) {
301                                 spin_unlock(&r0->lo_sub_lock);
302                                 cfs_waitq_wait(waiter, CFS_TASK_UNINT);
303                         } else {
304                                 spin_unlock(&r0->lo_sub_lock);
305                                 cfs_set_current_state(CFS_TASK_RUNNING);
306                                 break;
307                         }
308                 }
309                 cfs_waitq_del(&bkt->lsb_marche_funebre, waiter);
310         }
311         LASSERT(r0->lo_sub[idx] == NULL);
312 }
313
314 static int lov_delete_raid0(const struct lu_env *env, struct lov_object *lov,
315                             union lov_layout_state *state)
316 {
317         struct lov_layout_raid0 *r0 = &state->raid0;
318         struct lov_stripe_md    *lsm = lov->lo_lsm;
319         int i;
320
321         ENTRY;
322
323         dump_lsm(D_INODE, lsm);
324
325         lov_layout_wait(env, lov);
326         if (r0->lo_sub != NULL) {
327                 for (i = 0; i < r0->lo_nr; ++i) {
328                         struct lovsub_object *los = r0->lo_sub[i];
329
330                         if (los != NULL) {
331                                 cl_locks_prune(env, &los->lso_cl, 1);
332                                 /*
333                                  * If top-level object is to be evicted from
334                                  * the cache, so are its sub-objects.
335                                  */
336                                 lov_subobject_kill(env, lov, los, i);
337                         }
338                 }
339         }
340         cl_object_prune(env, &lov->lo_cl);
341         RETURN(0);
342 }
343
344 static void lov_fini_empty(const struct lu_env *env, struct lov_object *lov,
345                            union lov_layout_state *state)
346 {
347         LASSERT(lov->lo_type == LLT_EMPTY);
348 }
349
350 static void lov_fini_raid0(const struct lu_env *env, struct lov_object *lov,
351                            union lov_layout_state *state)
352 {
353         struct lov_layout_raid0 *r0 = &state->raid0;
354         ENTRY;
355
356         if (r0->lo_sub != NULL) {
357                 OBD_FREE_LARGE(r0->lo_sub, r0->lo_nr * sizeof r0->lo_sub[0]);
358                 r0->lo_sub = NULL;
359         }
360
361         dump_lsm(D_INODE, lov->lo_lsm);
362         lov_free_memmd(&lov->lo_lsm);
363
364         EXIT;
365 }
366
367 static int lov_print_empty(const struct lu_env *env, void *cookie,
368                            lu_printer_t p, const struct lu_object *o)
369 {
370         (*p)(env, cookie, "empty %d\n", lu2lov(o)->lo_layout_invalid);
371         return 0;
372 }
373
374 static int lov_print_raid0(const struct lu_env *env, void *cookie,
375                            lu_printer_t p, const struct lu_object *o)
376 {
377         struct lov_object       *lov = lu2lov(o);
378         struct lov_layout_raid0 *r0  = lov_r0(lov);
379         struct lov_stripe_md    *lsm = lov->lo_lsm;
380         int i;
381
382         (*p)(env, cookie, "stripes: %d, %svalid, lsm{%p 0x%08X %d %u %u}: \n",
383                 r0->lo_nr, lov->lo_layout_invalid ? "in" : "", lsm,
384                 lsm->lsm_magic, cfs_atomic_read(&lsm->lsm_refc),
385                 lsm->lsm_stripe_count, lsm->lsm_layout_gen);
386         for (i = 0; i < r0->lo_nr; ++i) {
387                 struct lu_object *sub;
388
389                 if (r0->lo_sub[i] != NULL) {
390                         sub = lovsub2lu(r0->lo_sub[i]);
391                         lu_object_print(env, cookie, p, sub);
392                 } else
393                         (*p)(env, cookie, "sub %d absent\n", i);
394         }
395         return 0;
396 }
397
398 /**
399  * Implements cl_object_operations::coo_attr_get() method for an object
400  * without stripes (LLT_EMPTY layout type).
401  *
402  * The only attributes this layer is authoritative in this case is
403  * cl_attr::cat_blocks---it's 0.
404  */
405 static int lov_attr_get_empty(const struct lu_env *env, struct cl_object *obj,
406                               struct cl_attr *attr)
407 {
408         attr->cat_blocks = 0;
409         return 0;
410 }
411
412 static int lov_attr_get_raid0(const struct lu_env *env, struct cl_object *obj,
413                               struct cl_attr *attr)
414 {
415         struct lov_object       *lov = cl2lov(obj);
416         struct lov_layout_raid0 *r0 = lov_r0(lov);
417         struct cl_attr          *lov_attr = &r0->lo_attr;
418         int                      result = 0;
419
420         ENTRY;
421
422         /* this is called w/o holding type guard mutex, so it must be inside
423          * an on going IO otherwise lsm may be replaced.
424          * LU-2117: it turns out there exists one exception. For mmaped files,
425          * the lock of those files may be requested in the other file's IO
426          * context, and this function is called in ccc_lock_state(), it will
427          * hit this assertion.
428          * Anyway, it's still okay to call attr_get w/o type guard as layout
429          * can't go if locks exist. */
430         /* LASSERT(cfs_atomic_read(&lsm->lsm_refc) > 1); */
431
432         if (!r0->lo_attr_valid) {
433                 struct lov_stripe_md    *lsm = lov->lo_lsm;
434                 struct ost_lvb          *lvb = &lov_env_info(env)->lti_lvb;
435                 __u64                    kms = 0;
436
437                 memset(lvb, 0, sizeof(*lvb));
438                 /* XXX: timestamps can be negative by sanity:test_39m,
439                  * how can it be? */
440                 lvb->lvb_atime = LLONG_MIN;
441                 lvb->lvb_ctime = LLONG_MIN;
442                 lvb->lvb_mtime = LLONG_MIN;
443
444                 /*
445                  * XXX that should be replaced with a loop over sub-objects,
446                  * doing cl_object_attr_get() on them. But for now, let's
447                  * reuse old lov code.
448                  */
449
450                 /*
451                  * XXX take lsm spin-lock to keep lov_merge_lvb_kms()
452                  * happy. It's not needed, because new code uses
453                  * ->coh_attr_guard spin-lock to protect consistency of
454                  * sub-object attributes.
455                  */
456                 lov_stripe_lock(lsm);
457                 result = lov_merge_lvb_kms(lsm, lvb, &kms);
458                 lov_stripe_unlock(lsm);
459                 if (result == 0) {
460                         cl_lvb2attr(lov_attr, lvb);
461                         lov_attr->cat_kms = kms;
462                         r0->lo_attr_valid = 1;
463                 }
464         }
465         if (result == 0) { /* merge results */
466                 attr->cat_blocks = lov_attr->cat_blocks;
467                 attr->cat_size = lov_attr->cat_size;
468                 attr->cat_kms = lov_attr->cat_kms;
469                 if (attr->cat_atime < lov_attr->cat_atime)
470                         attr->cat_atime = lov_attr->cat_atime;
471                 if (attr->cat_ctime < lov_attr->cat_ctime)
472                         attr->cat_ctime = lov_attr->cat_ctime;
473                 if (attr->cat_mtime < lov_attr->cat_mtime)
474                         attr->cat_mtime = lov_attr->cat_mtime;
475         }
476         RETURN(result);
477 }
478
479 const static struct lov_layout_operations lov_dispatch[] = {
480         [LLT_EMPTY] = {
481                 .llo_init      = lov_init_empty,
482                 .llo_delete    = lov_delete_empty,
483                 .llo_fini      = lov_fini_empty,
484                 .llo_install   = lov_install_empty,
485                 .llo_print     = lov_print_empty,
486                 .llo_page_init = lov_page_init_empty,
487                 .llo_lock_init = lov_lock_init_empty,
488                 .llo_io_init   = lov_io_init_empty,
489                 .llo_getattr   = lov_attr_get_empty
490         },
491         [LLT_RAID0] = {
492                 .llo_init      = lov_init_raid0,
493                 .llo_delete    = lov_delete_raid0,
494                 .llo_fini      = lov_fini_raid0,
495                 .llo_install   = lov_install_raid0,
496                 .llo_print     = lov_print_raid0,
497                 .llo_page_init = lov_page_init_raid0,
498                 .llo_lock_init = lov_lock_init_raid0,
499                 .llo_io_init   = lov_io_init_raid0,
500                 .llo_getattr   = lov_attr_get_raid0
501         }
502 };
503
504
505 /**
506  * Performs a double-dispatch based on the layout type of an object.
507  */
508 #define LOV_2DISPATCH_NOLOCK(obj, op, ...)                              \
509 ({                                                                      \
510         struct lov_object                      *__obj = (obj);          \
511         enum lov_layout_type                    __llt;                  \
512                                                                         \
513         __llt = __obj->lo_type;                                         \
514         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
515         lov_dispatch[__llt].op(__VA_ARGS__);                            \
516 })
517
518 static inline void lov_conf_freeze(struct lov_object *lov)
519 {
520         if (lov->lo_owner != cfs_current())
521                 down_read(&lov->lo_type_guard);
522 }
523
524 static inline void lov_conf_thaw(struct lov_object *lov)
525 {
526         if (lov->lo_owner != cfs_current())
527                 up_read(&lov->lo_type_guard);
528 }
529
530 #define LOV_2DISPATCH_MAYLOCK(obj, op, lock, ...)                       \
531 ({                                                                      \
532         struct lov_object                      *__obj = (obj);          \
533         int                                     __lock = !!(lock);      \
534         typeof(lov_dispatch[0].op(__VA_ARGS__)) __result;               \
535                                                                         \
536         if (__lock)                                                     \
537                 lov_conf_freeze(__obj);                                 \
538         __result = LOV_2DISPATCH_NOLOCK(obj, op, __VA_ARGS__);          \
539         if (__lock)                                                     \
540                 lov_conf_thaw(__obj);                                   \
541         __result;                                                       \
542 })
543
544 /**
545  * Performs a locked double-dispatch based on the layout type of an object.
546  */
547 #define LOV_2DISPATCH(obj, op, ...)                     \
548         LOV_2DISPATCH_MAYLOCK(obj, op, 1, __VA_ARGS__)
549
550 #define LOV_2DISPATCH_VOID(obj, op, ...)                                \
551 do {                                                                    \
552         struct lov_object                      *__obj = (obj);          \
553         enum lov_layout_type                    __llt;                  \
554                                                                         \
555         lov_conf_freeze(__obj);                                         \
556         __llt = __obj->lo_type;                                         \
557         LASSERT(0 <= __llt && __llt < ARRAY_SIZE(lov_dispatch));        \
558         lov_dispatch[__llt].op(__VA_ARGS__);                            \
559         lov_conf_thaw(__obj);                                           \
560 } while (0)
561
562 static void lov_conf_lock(struct lov_object *lov)
563 {
564         LASSERT(lov->lo_owner != cfs_current());
565         down_write(&lov->lo_type_guard);
566         LASSERT(lov->lo_owner == NULL);
567         lov->lo_owner = cfs_current();
568 }
569
570 static void lov_conf_unlock(struct lov_object *lov)
571 {
572         lov->lo_owner = NULL;
573         up_write(&lov->lo_type_guard);
574 }
575
576 static int lov_layout_wait(const struct lu_env *env, struct lov_object *lov)
577 {
578         struct l_wait_info lwi = { 0 };
579         ENTRY;
580
581         while (cfs_atomic_read(&lov->lo_active_ios) > 0) {
582                 CDEBUG(D_INODE, "file:"DFID" wait for active IO, now: %d.\n",
583                         PFID(lu_object_fid(lov2lu(lov))),
584                         cfs_atomic_read(&lov->lo_active_ios));
585
586                 l_wait_event(lov->lo_waitq,
587                              cfs_atomic_read(&lov->lo_active_ios) == 0, &lwi);
588         }
589         RETURN(0);
590 }
591
592 static int lov_layout_change(const struct lu_env *unused,
593                              struct lov_object *lov,
594                              const struct cl_object_conf *conf)
595 {
596         int result;
597         enum lov_layout_type llt = LLT_EMPTY;
598         union lov_layout_state *state = &lov->u;
599         const struct lov_layout_operations *old_ops;
600         const struct lov_layout_operations *new_ops;
601
602         struct cl_object_header *hdr = cl_object_header(&lov->lo_cl);
603         void *cookie;
604         struct lu_env *env;
605         int refcheck;
606         ENTRY;
607
608         LASSERT(0 <= lov->lo_type && lov->lo_type < ARRAY_SIZE(lov_dispatch));
609
610         if (conf->u.coc_md != NULL && conf->u.coc_md->lsm != NULL)
611                 llt = LLT_RAID0; /* only raid0 is supported. */
612         LASSERT(0 <= llt && llt < ARRAY_SIZE(lov_dispatch));
613
614         cookie = cl_env_reenter();
615         env = cl_env_get(&refcheck);
616         if (IS_ERR(env)) {
617                 cl_env_reexit(cookie);
618                 RETURN(PTR_ERR(env));
619         }
620
621         old_ops = &lov_dispatch[lov->lo_type];
622         new_ops = &lov_dispatch[llt];
623
624         result = old_ops->llo_delete(env, lov, &lov->u);
625         if (result == 0) {
626                 old_ops->llo_fini(env, lov, &lov->u);
627
628                 LASSERT(cfs_atomic_read(&lov->lo_active_ios) == 0);
629                 LASSERT(hdr->coh_tree.rnode == NULL);
630                 LASSERT(hdr->coh_pages == 0);
631
632                 lov->lo_type = LLT_EMPTY;
633                 result = new_ops->llo_init(env,
634                                         lu2lov_dev(lov->lo_cl.co_lu.lo_dev),
635                                         lov, conf, state);
636                 if (result == 0) {
637                         new_ops->llo_install(env, lov, state);
638                         lov->lo_type = llt;
639                 } else {
640                         new_ops->llo_delete(env, lov, state);
641                         new_ops->llo_fini(env, lov, state);
642                         /* this file becomes an EMPTY file. */
643                 }
644         }
645
646         cl_env_put(env, &refcheck);
647         cl_env_reexit(cookie);
648         RETURN(result);
649 }
650
651 /*****************************************************************************
652  *
653  * Lov object operations.
654  *
655  */
656
657 int lov_object_init(const struct lu_env *env, struct lu_object *obj,
658                     const struct lu_object_conf *conf)
659 {
660         struct lov_device            *dev   = lu2lov_dev(obj->lo_dev);
661         struct lov_object            *lov   = lu2lov(obj);
662         const struct cl_object_conf  *cconf = lu2cl_conf(conf);
663         union  lov_layout_state      *set   = &lov->u;
664         const struct lov_layout_operations *ops;
665         int result;
666
667         ENTRY;
668         init_rwsem(&lov->lo_type_guard);
669         cfs_atomic_set(&lov->lo_active_ios, 0);
670         cfs_waitq_init(&lov->lo_waitq);
671
672         cl_object_page_init(lu2cl(obj), sizeof(struct lov_page));
673
674         /* no locking is necessary, as object is being created */
675         lov->lo_type = cconf->u.coc_md->lsm != NULL ? LLT_RAID0 : LLT_EMPTY;
676         ops = &lov_dispatch[lov->lo_type];
677         result = ops->llo_init(env, dev, lov, cconf, set);
678         if (result == 0)
679                 ops->llo_install(env, lov, set);
680         RETURN(result);
681 }
682
683 static int lov_conf_set(const struct lu_env *env, struct cl_object *obj,
684                         const struct cl_object_conf *conf)
685 {
686         struct lov_stripe_md *lsm = NULL;
687         struct lov_object *lov = cl2lov(obj);
688         int result = 0;
689         ENTRY;
690
691         lov_conf_lock(lov);
692         if (conf->coc_opc == OBJECT_CONF_INVALIDATE) {
693                 lov->lo_layout_invalid = true;
694                 GOTO(out, result = 0);
695         }
696
697         if (conf->coc_opc == OBJECT_CONF_WAIT) {
698                 if (lov->lo_layout_invalid &&
699                     cfs_atomic_read(&lov->lo_active_ios) > 0) {
700                         lov_conf_unlock(lov);
701                         result = lov_layout_wait(env, lov);
702                         lov_conf_lock(lov);
703                 }
704                 GOTO(out, result);
705         }
706
707         LASSERT(conf->coc_opc == OBJECT_CONF_SET);
708
709         if (conf->u.coc_md != NULL)
710                 lsm = conf->u.coc_md->lsm;
711         if ((lsm == NULL && lov->lo_lsm == NULL) ||
712             (lsm != NULL && lov->lo_lsm != NULL &&
713              lov->lo_lsm->lsm_layout_gen == lsm->lsm_layout_gen)) {
714                 /* same version of layout */
715                 lov->lo_layout_invalid = false;
716                 GOTO(out, result = 0);
717         }
718
719         /* will change layout - check if there still exists active IO. */
720         if (cfs_atomic_read(&lov->lo_active_ios) > 0) {
721                 lov->lo_layout_invalid = true;
722                 GOTO(out, result = -EBUSY);
723         }
724
725         lov->lo_layout_invalid = lov_layout_change(env, lov, conf);
726         EXIT;
727
728 out:
729         lov_conf_unlock(lov);
730         RETURN(result);
731 }
732
733 static void lov_object_delete(const struct lu_env *env, struct lu_object *obj)
734 {
735         struct lov_object *lov = lu2lov(obj);
736
737         ENTRY;
738         LOV_2DISPATCH_VOID(lov, llo_delete, env, lov, &lov->u);
739         EXIT;
740 }
741
742 static void lov_object_free(const struct lu_env *env, struct lu_object *obj)
743 {
744         struct lov_object *lov = lu2lov(obj);
745
746         ENTRY;
747         LOV_2DISPATCH_VOID(lov, llo_fini, env, lov, &lov->u);
748         lu_object_fini(obj);
749         OBD_SLAB_FREE_PTR(lov, lov_object_kmem);
750         EXIT;
751 }
752
753 static int lov_object_print(const struct lu_env *env, void *cookie,
754                             lu_printer_t p, const struct lu_object *o)
755 {
756         return LOV_2DISPATCH_NOLOCK(lu2lov(o), llo_print, env, cookie, p, o);
757 }
758
759 int lov_page_init(const struct lu_env *env, struct cl_object *obj,
760                 struct cl_page *page, cfs_page_t *vmpage)
761 {
762         return LOV_2DISPATCH_NOLOCK(cl2lov(obj),
763                                     llo_page_init, env, obj, page, vmpage);
764 }
765
766 /**
767  * Implements cl_object_operations::clo_io_init() method for lov
768  * layer. Dispatches to the appropriate layout io initialization method.
769  */
770 int lov_io_init(const struct lu_env *env, struct cl_object *obj,
771                 struct cl_io *io)
772 {
773         CL_IO_SLICE_CLEAN(lov_env_io(env), lis_cl);
774         return LOV_2DISPATCH_MAYLOCK(cl2lov(obj), llo_io_init,
775                                      !io->ci_ignore_layout, env, obj, io);
776 }
777
778 /**
779  * An implementation of cl_object_operations::clo_attr_get() method for lov
780  * layer. For raid0 layout this collects and merges attributes of all
781  * sub-objects.
782  */
783 static int lov_attr_get(const struct lu_env *env, struct cl_object *obj,
784                         struct cl_attr *attr)
785 {
786         /* do not take lock, as this function is called under a
787          * spin-lock. Layout is protected from changing by ongoing IO. */
788         return LOV_2DISPATCH_NOLOCK(cl2lov(obj), llo_getattr, env, obj, attr);
789 }
790
791 static int lov_attr_set(const struct lu_env *env, struct cl_object *obj,
792                         const struct cl_attr *attr, unsigned valid)
793 {
794         /*
795          * No dispatch is required here, as no layout implements this.
796          */
797         return 0;
798 }
799
800 int lov_lock_init(const struct lu_env *env, struct cl_object *obj,
801                   struct cl_lock *lock, const struct cl_io *io)
802 {
803         /* No need to lock because we've taken one refcount of layout.  */
804         return LOV_2DISPATCH_NOLOCK(cl2lov(obj), llo_lock_init, env, obj, lock,
805                                     io);
806 }
807
808 static const struct cl_object_operations lov_ops = {
809         .coo_page_init = lov_page_init,
810         .coo_lock_init = lov_lock_init,
811         .coo_io_init   = lov_io_init,
812         .coo_attr_get  = lov_attr_get,
813         .coo_attr_set  = lov_attr_set,
814         .coo_conf_set  = lov_conf_set
815 };
816
817 static const struct lu_object_operations lov_lu_obj_ops = {
818         .loo_object_init      = lov_object_init,
819         .loo_object_delete    = lov_object_delete,
820         .loo_object_release   = NULL,
821         .loo_object_free      = lov_object_free,
822         .loo_object_print     = lov_object_print,
823         .loo_object_invariant = NULL
824 };
825
826 struct lu_object *lov_object_alloc(const struct lu_env *env,
827                                    const struct lu_object_header *unused,
828                                    struct lu_device *dev)
829 {
830         struct lov_object *lov;
831         struct lu_object  *obj;
832
833         ENTRY;
834         OBD_SLAB_ALLOC_PTR_GFP(lov, lov_object_kmem, CFS_ALLOC_IO);
835         if (lov != NULL) {
836                 obj = lov2lu(lov);
837                 lu_object_init(obj, NULL, dev);
838                 lov->lo_cl.co_ops = &lov_ops;
839                 lov->lo_type = -1; /* invalid, to catch uninitialized type */
840                 /*
841                  * object io operation vector (cl_object::co_iop) is installed
842                  * later in lov_object_init(), as different vectors are used
843                  * for object with different layouts.
844                  */
845                 obj->lo_ops = &lov_lu_obj_ops;
846         } else
847                 obj = NULL;
848         RETURN(obj);
849 }
850
851 struct lov_stripe_md *lov_lsm_addref(struct lov_object *lov)
852 {
853         struct lov_stripe_md *lsm = NULL;
854
855         lov_conf_freeze(lov);
856         if (lov->lo_lsm != NULL) {
857                 lsm = lsm_addref(lov->lo_lsm);
858                 CDEBUG(D_INODE, "lsm %p addref %d/%d by %p.\n",
859                         lsm, cfs_atomic_read(&lsm->lsm_refc),
860                         lov->lo_layout_invalid, cfs_current());
861         }
862         lov_conf_thaw(lov);
863         return lsm;
864 }
865
866 void lov_lsm_decref(struct lov_object *lov, struct lov_stripe_md *lsm)
867 {
868         if (lsm == NULL)
869                 return;
870
871         CDEBUG(D_INODE, "lsm %p decref %d by %p.\n",
872                 lsm, cfs_atomic_read(&lsm->lsm_refc), cfs_current());
873
874         lov_free_memmd(&lsm);
875 }
876
877 struct lov_stripe_md *lov_lsm_get(struct cl_object *clobj)
878 {
879         struct lu_object *luobj;
880         struct lov_stripe_md *lsm = NULL;
881
882         if (clobj == NULL)
883                 return NULL;
884
885         luobj = lu_object_locate(&cl_object_header(clobj)->coh_lu,
886                                  &lov_device_type);
887         if (luobj != NULL)
888                 lsm = lov_lsm_addref(lu2lov(luobj));
889         return lsm;
890 }
891 EXPORT_SYMBOL(lov_lsm_get);
892
893 void lov_lsm_put(struct cl_object *unused, struct lov_stripe_md *lsm)
894 {
895         if (lsm != NULL)
896                 lov_free_memmd(&lsm);
897 }
898 EXPORT_SYMBOL(lov_lsm_put);
899
900 int lov_read_and_clear_async_rc(struct cl_object *clob)
901 {
902         struct lu_object *luobj;
903         int rc = 0;
904         ENTRY;
905
906         luobj = lu_object_locate(&cl_object_header(clob)->coh_lu,
907                                  &lov_device_type);
908         if (luobj != NULL) {
909                 struct lov_object *lov = lu2lov(luobj);
910
911                 lov_conf_freeze(lov);
912                 switch (lov->lo_type) {
913                 case LLT_RAID0: {
914                         struct lov_stripe_md *lsm;
915                         int i;
916
917                         lsm = lov->lo_lsm;
918                         LASSERT(lsm != NULL);
919                         for (i = 0; i < lsm->lsm_stripe_count; i++) {
920                                 struct lov_oinfo *loi = lsm->lsm_oinfo[i];
921                                 if (loi->loi_ar.ar_rc && !rc)
922                                         rc = loi->loi_ar.ar_rc;
923                                 loi->loi_ar.ar_rc = 0;
924                         }
925                 }
926                 case LLT_EMPTY:
927                         break;
928                 default:
929                         LBUG();
930                 }
931                 lov_conf_thaw(lov);
932         }
933         RETURN(rc);
934 }
935 EXPORT_SYMBOL(lov_read_and_clear_async_rc);
936
937 /** @} lov */