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LU-2684 fid: unify ostid and FID
[fs/lustre-release.git] / lustre / obdclass / llog_osd.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) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 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  * lustre/obdclass/llog_osd.c - low level llog routines on top of OSD API
37  *
38  * Author: Alexey Zhuravlev <alexey.zhuravlev@intel.com>
39  * Author: Mikhail Pershin <mike.pershin@intel.com>
40  */
41
42 #define DEBUG_SUBSYSTEM S_LOG
43
44 #ifndef EXPORT_SYMTAB
45 #define EXPORT_SYMTAB
46 #endif
47
48 #include <obd.h>
49 #include <obd_class.h>
50 #include <lustre_fid.h>
51 #include <dt_object.h>
52
53 #include "llog_internal.h"
54 #include "local_storage.h"
55
56 /*
57  * - multi-chunks or big-declaration approach
58  * - use unique sequence instead of llog sb tracking unique ids
59  * - re-use existing environment
60  * - named llog support (can be used for testing only at the present)
61  * - llog_origin_connect() work with OSD API
62  */
63
64 static int llog_osd_declare_new_object(const struct lu_env *env,
65                                        struct local_oid_storage *los,
66                                        struct dt_object *o,
67                                        struct thandle *th)
68 {
69         struct llog_thread_info *lgi = llog_info(env);
70
71         lgi->lgi_attr.la_valid = LA_MODE;
72         lgi->lgi_attr.la_mode = S_IFREG | S_IRUGO | S_IWUSR;
73         lgi->lgi_dof.dof_type = dt_mode_to_dft(S_IFREG);
74
75         return local_object_declare_create(env, los, o, &lgi->lgi_attr,
76                                            &lgi->lgi_dof, th);
77 }
78
79 static int llog_osd_create_new_object(const struct lu_env *env,
80                                       struct local_oid_storage *los,
81                                       struct dt_object *o,
82                                       struct thandle *th)
83 {
84         struct llog_thread_info *lgi = llog_info(env);
85
86         lgi->lgi_attr.la_valid = LA_MODE;
87         lgi->lgi_attr.la_mode = S_IFREG | S_IRUGO | S_IWUSR;
88         lgi->lgi_dof.dof_type = dt_mode_to_dft(S_IFREG);
89
90         return local_object_create(env, los, o, &lgi->lgi_attr,
91                                    &lgi->lgi_dof, th);
92 }
93
94 static int llog_osd_pad(const struct lu_env *env, struct dt_object *o,
95                         loff_t *off, int len, int index, struct thandle *th)
96 {
97         struct llog_thread_info *lgi = llog_info(env);
98         int                      rc;
99
100         ENTRY;
101
102         LASSERT(th);
103         LASSERT(off);
104         LASSERT(len >= LLOG_MIN_REC_SIZE && (len & 0x7) == 0);
105
106         lgi->lgi_tail.lrt_len = lgi->lgi_lrh.lrh_len = len;
107         lgi->lgi_tail.lrt_index = lgi->lgi_lrh.lrh_index = index;
108         lgi->lgi_lrh.lrh_type = LLOG_PAD_MAGIC;
109
110         lgi->lgi_buf.lb_buf = &lgi->lgi_lrh;
111         lgi->lgi_buf.lb_len = sizeof(lgi->lgi_lrh);
112         dt_write_lock(env, o, 0);
113         rc = dt_record_write(env, o, &lgi->lgi_buf, off, th);
114         if (rc) {
115                 CERROR("%s: error writing padding record: rc = %d\n",
116                        o->do_lu.lo_dev->ld_obd->obd_name, rc);
117                 GOTO(out, rc);
118         }
119
120         lgi->lgi_buf.lb_buf = &lgi->lgi_tail;
121         lgi->lgi_buf.lb_len = sizeof(lgi->lgi_tail);
122         *off += len - sizeof(lgi->lgi_lrh) - sizeof(lgi->lgi_tail);
123         rc = dt_record_write(env, o, &lgi->lgi_buf, off, th);
124         if (rc)
125                 CERROR("%s: error writing padding record: rc = %d\n",
126                        o->do_lu.lo_dev->ld_obd->obd_name, rc);
127 out:
128         dt_write_unlock(env, o);
129         RETURN(rc);
130 }
131
132 static int llog_osd_write_blob(const struct lu_env *env, struct dt_object *o,
133                                struct llog_rec_hdr *rec, void *buf,
134                                loff_t *off, struct thandle *th)
135 {
136         struct llog_thread_info *lgi = llog_info(env);
137         int                      buflen = rec->lrh_len;
138         int                      rc;
139
140         ENTRY;
141
142         LASSERT(env);
143         LASSERT(o);
144
145         if (buflen == 0)
146                 CWARN("0-length record\n");
147
148         CDEBUG(D_OTHER, "write blob with type %x, buf %p/%u at off %llu\n",
149                rec->lrh_type, buf, buflen, *off);
150
151         lgi->lgi_attr.la_valid = LA_SIZE;
152         lgi->lgi_attr.la_size = *off;
153
154         if (!buf) {
155                 lgi->lgi_buf.lb_len = buflen;
156                 lgi->lgi_buf.lb_buf = rec;
157                 rc = dt_record_write(env, o, &lgi->lgi_buf, off, th);
158                 if (rc)
159                         CERROR("%s: error writing log record: rc = %d\n",
160                                o->do_lu.lo_dev->ld_obd->obd_name, rc);
161                 GOTO(out, rc);
162         }
163
164         /* the buf case */
165         /* protect the following 3 writes from concurrent read */
166         dt_write_lock(env, o, 0);
167         rec->lrh_len = sizeof(*rec) + buflen + sizeof(lgi->lgi_tail);
168         lgi->lgi_buf.lb_len = sizeof(*rec);
169         lgi->lgi_buf.lb_buf = rec;
170         rc = dt_record_write(env, o, &lgi->lgi_buf, off, th);
171         if (rc) {
172                 CERROR("%s: error writing log hdr: rc = %d\n",
173                        o->do_lu.lo_dev->ld_obd->obd_name, rc);
174                 GOTO(out_unlock, rc);
175         }
176
177         lgi->lgi_buf.lb_len = buflen;
178         lgi->lgi_buf.lb_buf = buf;
179         rc = dt_record_write(env, o, &lgi->lgi_buf, off, th);
180         if (rc) {
181                 CERROR("%s: error writing log buffer: rc = %d\n",
182                        o->do_lu.lo_dev->ld_obd->obd_name,  rc);
183                 GOTO(out_unlock, rc);
184         }
185
186         lgi->lgi_tail.lrt_len = rec->lrh_len;
187         lgi->lgi_tail.lrt_index = rec->lrh_index;
188         lgi->lgi_buf.lb_len = sizeof(lgi->lgi_tail);
189         lgi->lgi_buf.lb_buf = &lgi->lgi_tail;
190         rc = dt_record_write(env, o, &lgi->lgi_buf, off, th);
191         if (rc)
192                 CERROR("%s: error writing log tail: rc = %d\n",
193                        o->do_lu.lo_dev->ld_obd->obd_name, rc);
194
195 out_unlock:
196         dt_write_unlock(env, o);
197
198 out:
199         /* cleanup the content written above */
200         if (rc) {
201                 dt_punch(env, o, lgi->lgi_attr.la_size, OBD_OBJECT_EOF, th,
202                          BYPASS_CAPA);
203                 dt_attr_set(env, o, &lgi->lgi_attr, th, BYPASS_CAPA);
204         }
205
206         RETURN(rc);
207 }
208
209 static int llog_osd_read_header(const struct lu_env *env,
210                                 struct llog_handle *handle)
211 {
212         struct llog_rec_hdr     *llh_hdr;
213         struct dt_object        *o;
214         struct llog_thread_info *lgi;
215         int                      rc;
216
217         ENTRY;
218
219         LASSERT(sizeof(*handle->lgh_hdr) == LLOG_CHUNK_SIZE);
220
221         o = handle->lgh_obj;
222         LASSERT(o);
223
224         lgi = llog_info(env);
225
226         rc = dt_attr_get(env, o, &lgi->lgi_attr, NULL);
227         if (rc)
228                 RETURN(rc);
229
230         LASSERT(lgi->lgi_attr.la_valid & LA_SIZE);
231
232         if (lgi->lgi_attr.la_size == 0) {
233                 CDEBUG(D_HA, "not reading header from 0-byte log\n");
234                 RETURN(LLOG_EEMPTY);
235         }
236
237         lgi->lgi_off = 0;
238         lgi->lgi_buf.lb_buf = handle->lgh_hdr;
239         lgi->lgi_buf.lb_len = LLOG_CHUNK_SIZE;
240
241         rc = dt_record_read(env, o, &lgi->lgi_buf, &lgi->lgi_off);
242         if (rc) {
243                 CERROR("%s: error reading log header from "DFID": rc = %d\n",
244                        o->do_lu.lo_dev->ld_obd->obd_name,
245                        PFID(lu_object_fid(&o->do_lu)), rc);
246                 RETURN(rc);
247         }
248
249         llh_hdr = &handle->lgh_hdr->llh_hdr;
250         if (LLOG_REC_HDR_NEEDS_SWABBING(llh_hdr))
251                 lustre_swab_llog_hdr(handle->lgh_hdr);
252
253         if (llh_hdr->lrh_type != LLOG_HDR_MAGIC) {
254                 CERROR("%s: bad log %s "DFID" header magic: %#x "
255                        "(expected %#x)\n", o->do_lu.lo_dev->ld_obd->obd_name,
256                        handle->lgh_name ? handle->lgh_name : "",
257                        PFID(lu_object_fid(&o->do_lu)),
258                        llh_hdr->lrh_type, LLOG_HDR_MAGIC);
259                 RETURN(-EIO);
260         } else if (llh_hdr->lrh_len != LLOG_CHUNK_SIZE) {
261                 CERROR("%s: incorrectly sized log %s "DFID" header: "
262                        "%#x (expected %#x)\n"
263                        "you may need to re-run lconf --write_conf.\n",
264                        o->do_lu.lo_dev->ld_obd->obd_name,
265                        handle->lgh_name ? handle->lgh_name : "",
266                        PFID(lu_object_fid(&o->do_lu)),
267                        llh_hdr->lrh_len, LLOG_CHUNK_SIZE);
268                 RETURN(-EIO);
269         }
270
271         handle->lgh_last_idx = handle->lgh_hdr->llh_tail.lrt_index;
272
273         RETURN(0);
274 }
275
276 static int llog_osd_declare_write_rec(const struct lu_env *env,
277                                       struct llog_handle *loghandle,
278                                       struct llog_rec_hdr *rec,
279                                       int idx, struct thandle *th)
280 {
281         struct llog_thread_info *lgi = llog_info(env);
282         struct dt_object        *o;
283         int                      rc;
284
285         ENTRY;
286
287         LASSERT(env);
288         LASSERT(th);
289         LASSERT(loghandle);
290
291         o = loghandle->lgh_obj;
292         LASSERT(o);
293
294         /* each time we update header */
295         rc = dt_declare_record_write(env, o, sizeof(struct llog_log_hdr), 0,
296                                      th);
297         if (rc || idx == 0) /* if error or just header */
298                 RETURN(rc);
299
300         if (dt_object_exists(o)) {
301                 rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
302                 lgi->lgi_off = lgi->lgi_attr.la_size;
303                 LASSERT(ergo(rc == 0, lgi->lgi_attr.la_valid & LA_SIZE));
304                 if (rc)
305                         RETURN(rc);
306
307                 rc = dt_declare_punch(env, o, lgi->lgi_off, OBD_OBJECT_EOF, th);
308                 if (rc)
309                         RETURN(rc);
310         } else {
311                 lgi->lgi_off = 0;
312         }
313
314         /* XXX: implement declared window or multi-chunks approach */
315         rc = dt_declare_record_write(env, o, 32 * 1024, lgi->lgi_off, th);
316
317         RETURN(rc);
318 }
319
320 /* returns negative in on error; 0 if success && reccookie == 0; 1 otherwise */
321 /* appends if idx == -1, otherwise overwrites record idx. */
322 static int llog_osd_write_rec(const struct lu_env *env,
323                               struct llog_handle *loghandle,
324                               struct llog_rec_hdr *rec,
325                               struct llog_cookie *reccookie, int cookiecount,
326                               void *buf, int idx, struct thandle *th)
327 {
328         struct llog_thread_info *lgi = llog_info(env);
329         struct llog_log_hdr     *llh;
330         int                      reclen = rec->lrh_len;
331         int                      index, rc, old_tail_idx;
332         struct llog_rec_tail    *lrt;
333         struct dt_object        *o;
334         size_t                   left;
335
336         ENTRY;
337
338         LASSERT(env);
339         llh = loghandle->lgh_hdr;
340         LASSERT(llh);
341         o = loghandle->lgh_obj;
342         LASSERT(o);
343         LASSERT(th);
344
345         CDEBUG(D_OTHER, "new record %x to "DFID"\n",
346                rec->lrh_type, PFID(lu_object_fid(&o->do_lu)));
347
348         /* record length should not bigger than LLOG_CHUNK_SIZE */
349         if (buf)
350                 rc = (reclen > LLOG_CHUNK_SIZE - sizeof(struct llog_rec_hdr) -
351                       sizeof(struct llog_rec_tail)) ? -E2BIG : 0;
352         else
353                 rc = (reclen > LLOG_CHUNK_SIZE) ? -E2BIG : 0;
354         if (rc)
355                 RETURN(rc);
356
357         rc = dt_attr_get(env, o, &lgi->lgi_attr, NULL);
358         if (rc)
359                 RETURN(rc);
360
361         if (buf)
362                 /* write_blob adds header and tail to lrh_len. */
363                 reclen = sizeof(*rec) + rec->lrh_len +
364                          sizeof(struct llog_rec_tail);
365
366         if (idx != -1) {
367                 /* no header: only allowed to insert record 1 */
368                 if (idx != 1 && lgi->lgi_attr.la_size == 0)
369                         LBUG();
370
371                 if (idx && llh->llh_size && llh->llh_size != rec->lrh_len)
372                         RETURN(-EINVAL);
373
374                 if (!ext2_test_bit(idx, llh->llh_bitmap))
375                         CERROR("%s: modify unset record %u\n",
376                                o->do_lu.lo_dev->ld_obd->obd_name, idx);
377                 if (idx != rec->lrh_index)
378                         CERROR("%s: index mismatch %d %u\n",
379                                o->do_lu.lo_dev->ld_obd->obd_name, idx,
380                                rec->lrh_index);
381
382                 lgi->lgi_off = 0;
383                 rc = llog_osd_write_blob(env, o, &llh->llh_hdr, NULL,
384                                          &lgi->lgi_off, th);
385                 /* we are done if we only write the header or on error */
386                 if (rc || idx == 0)
387                         RETURN(rc);
388
389                 if (buf) {
390                         /* We assume that caller has set lgh_cur_* */
391                         lgi->lgi_off = loghandle->lgh_cur_offset;
392                         CDEBUG(D_OTHER,
393                                "modify record "DOSTID": idx:%d/%u/%d, len:%u "
394                                "offset %llu\n",
395                                POSTID(&loghandle->lgh_id.lgl_oi), idx,
396                                rec->lrh_index,
397                                loghandle->lgh_cur_idx, rec->lrh_len,
398                                (long long)(lgi->lgi_off - sizeof(*llh)));
399                         if (rec->lrh_index != loghandle->lgh_cur_idx) {
400                                 CERROR("%s: modify idx mismatch %u/%d\n",
401                                        o->do_lu.lo_dev->ld_obd->obd_name, idx,
402                                        loghandle->lgh_cur_idx);
403                                 RETURN(-EFAULT);
404                         }
405                 } else {
406                         /* Assumes constant lrh_len */
407                         lgi->lgi_off = sizeof(*llh) + (idx - 1) * reclen;
408                 }
409
410                 rc = llog_osd_write_blob(env, o, rec, buf, &lgi->lgi_off, th);
411                 if (rc == 0 && reccookie) {
412                         reccookie->lgc_lgl = loghandle->lgh_id;
413                         reccookie->lgc_index = idx;
414                         rc = 1;
415                 }
416                 RETURN(rc);
417         }
418
419         /* Make sure that records don't cross a chunk boundary, so we can
420          * process them page-at-a-time if needed.  If it will cross a chunk
421          * boundary, write in a fake (but referenced) entry to pad the chunk.
422          *
423          * We know that llog_current_log() will return a loghandle that is
424          * big enough to hold reclen, so all we care about is padding here.
425          */
426         LASSERT(lgi->lgi_attr.la_valid & LA_SIZE);
427         lgi->lgi_off = lgi->lgi_attr.la_size;
428         left = LLOG_CHUNK_SIZE - (lgi->lgi_off & (LLOG_CHUNK_SIZE - 1));
429         /* NOTE: padding is a record, but no bit is set */
430         if (left != 0 && left != reclen &&
431             left < (reclen + LLOG_MIN_REC_SIZE)) {
432                 index = loghandle->lgh_last_idx + 1;
433                 rc = llog_osd_pad(env, o, &lgi->lgi_off, left, index, th);
434                 if (rc)
435                         RETURN(rc);
436                 loghandle->lgh_last_idx++; /*for pad rec*/
437         }
438         /* if it's the last idx in log file, then return -ENOSPC */
439         if (loghandle->lgh_last_idx >= LLOG_BITMAP_SIZE(llh) - 1)
440                 RETURN(-ENOSPC);
441
442         loghandle->lgh_last_idx++;
443         index = loghandle->lgh_last_idx;
444         LASSERT(index < LLOG_BITMAP_SIZE(llh));
445         rec->lrh_index = index;
446         if (buf == NULL) {
447                 lrt = (struct llog_rec_tail *)((char *)rec + rec->lrh_len -
448                                                sizeof(*lrt));
449                 lrt->lrt_len = rec->lrh_len;
450                 lrt->lrt_index = rec->lrh_index;
451         }
452         /* The caller should make sure only 1 process access the lgh_last_idx,
453          * Otherwise it might hit the assert.*/
454         LASSERT(index < LLOG_BITMAP_SIZE(llh));
455         spin_lock(&loghandle->lgh_hdr_lock);
456         if (ext2_set_bit(index, llh->llh_bitmap)) {
457                 CERROR("%s: index %u already set in log bitmap\n",
458                        o->do_lu.lo_dev->ld_obd->obd_name, index);
459                 spin_unlock(&loghandle->lgh_hdr_lock);
460                 LBUG(); /* should never happen */
461         }
462         llh->llh_count++;
463         spin_unlock(&loghandle->lgh_hdr_lock);
464         old_tail_idx = llh->llh_tail.lrt_index;
465         llh->llh_tail.lrt_index = index;
466
467         lgi->lgi_off = 0;
468         rc = llog_osd_write_blob(env, o, &llh->llh_hdr, NULL, &lgi->lgi_off,
469                                  th);
470         if (rc)
471                 GOTO(out, rc);
472
473         rc = dt_attr_get(env, o, &lgi->lgi_attr, NULL);
474         if (rc)
475                 GOTO(out, rc);
476
477         LASSERT(lgi->lgi_attr.la_valid & LA_SIZE);
478         lgi->lgi_off = lgi->lgi_attr.la_size;
479
480         rc = llog_osd_write_blob(env, o, rec, buf, &lgi->lgi_off, th);
481
482 out:
483         /* cleanup llog for error case */
484         if (rc) {
485                 spin_lock(&loghandle->lgh_hdr_lock);
486                 ext2_clear_bit(index, llh->llh_bitmap);
487                 llh->llh_count--;
488                 spin_unlock(&loghandle->lgh_hdr_lock);
489
490                 /* restore the header */
491                 loghandle->lgh_last_idx--;
492                 llh->llh_tail.lrt_index = old_tail_idx;
493                 lgi->lgi_off = 0;
494                 llog_osd_write_blob(env, o, &llh->llh_hdr, NULL,
495                                     &lgi->lgi_off, th);
496         }
497
498         CDEBUG(D_RPCTRACE, "added record "DOSTID": idx: %u, %u\n",
499                POSTID(&loghandle->lgh_id.lgl_oi), index, rec->lrh_len);
500         if (rc == 0 && reccookie) {
501                 reccookie->lgc_lgl = loghandle->lgh_id;
502                 reccookie->lgc_index = index;
503                 if ((rec->lrh_type == MDS_UNLINK_REC) ||
504                     (rec->lrh_type == MDS_SETATTR64_REC))
505                         reccookie->lgc_subsys = LLOG_MDS_OST_ORIG_CTXT;
506                 else if (rec->lrh_type == OST_SZ_REC)
507                         reccookie->lgc_subsys = LLOG_SIZE_ORIG_CTXT;
508                 else
509                         reccookie->lgc_subsys = -1;
510                 rc = 1;
511         }
512         RETURN(rc);
513 }
514
515 /* We can skip reading at least as many log blocks as the number of
516  * minimum sized log records we are skipping.  If it turns out
517  * that we are not far enough along the log (because the
518  * actual records are larger than minimum size) we just skip
519  * some more records.
520  */
521 static void llog_skip_over(__u64 *off, int curr, int goal)
522 {
523         if (goal <= curr)
524                 return;
525         *off = (*off + (goal - curr - 1) * LLOG_MIN_REC_SIZE) &
526                 ~(LLOG_CHUNK_SIZE - 1);
527 }
528
529 /* sets:
530  *  - cur_offset to the furthest point read in the log file
531  *  - cur_idx to the log index preceeding cur_offset
532  * returns -EIO/-EINVAL on error
533  */
534 static int llog_osd_next_block(const struct lu_env *env,
535                                struct llog_handle *loghandle, int *cur_idx,
536                                int next_idx, __u64 *cur_offset, void *buf,
537                                int len)
538 {
539         struct llog_thread_info *lgi = llog_info(env);
540         struct dt_object        *o;
541         struct dt_device        *dt;
542         int                      rc;
543
544         ENTRY;
545
546         LASSERT(env);
547         LASSERT(lgi);
548
549         if (len == 0 || len & (LLOG_CHUNK_SIZE - 1))
550                 RETURN(-EINVAL);
551
552         CDEBUG(D_OTHER, "looking for log index %u (cur idx %u off "LPU64")\n",
553                next_idx, *cur_idx, *cur_offset);
554
555         LASSERT(loghandle);
556         LASSERT(loghandle->lgh_ctxt);
557
558         o = loghandle->lgh_obj;
559         LASSERT(o);
560         LASSERT(dt_object_exists(o));
561         dt = lu2dt_dev(o->do_lu.lo_dev);
562         LASSERT(dt);
563
564         rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
565         if (rc)
566                 GOTO(out, rc);
567
568         while (*cur_offset < lgi->lgi_attr.la_size) {
569                 struct llog_rec_hdr     *rec, *last_rec;
570                 struct llog_rec_tail    *tail;
571
572                 llog_skip_over(cur_offset, *cur_idx, next_idx);
573
574                 /* read up to next LLOG_CHUNK_SIZE block */
575                 lgi->lgi_buf.lb_len = LLOG_CHUNK_SIZE -
576                                       (*cur_offset & (LLOG_CHUNK_SIZE - 1));
577                 lgi->lgi_buf.lb_buf = buf;
578
579                 /* Note: read lock is not needed around la_size get above at
580                  * the time of dt_attr_get(). There are only two cases that
581                  * matter. Either la_size == cur_offset, in which case the
582                  * entire read is skipped, or la_size > cur_offset and the loop
583                  * is entered and this thread is blocked at dt_read_lock()
584                  * until the write is completed. When the write completes, then
585                  * the dt_read() will be done with the full length, and will
586                  * get the full data.
587                  */
588                 dt_read_lock(env, o, 0);
589                 rc = dt_read(env, o, &lgi->lgi_buf, cur_offset);
590                 dt_read_unlock(env, o);
591                 if (rc < 0) {
592                         CERROR("%s: can't read llog block from log "DFID
593                                " offset "LPU64": rc = %d\n",
594                                o->do_lu.lo_dev->ld_obd->obd_name,
595                                PFID(lu_object_fid(&o->do_lu)), *cur_offset,
596                                rc);
597                         GOTO(out, rc);
598                 }
599
600                 if (rc < len) {
601                         /* signal the end of the valid buffer to
602                          * llog_process */
603                         memset(buf + rc, 0, len - rc);
604                 }
605
606                 if (rc == 0) /* end of file, nothing to do */
607                         GOTO(out, rc);
608
609                 if (rc < sizeof(*tail)) {
610                         CERROR("%s: invalid llog block at log id "DOSTID"/%u "
611                                "offset "LPU64"\n",
612                                o->do_lu.lo_dev->ld_obd->obd_name,
613                                POSTID(&loghandle->lgh_id.lgl_oi),
614                                loghandle->lgh_id.lgl_ogen, *cur_offset);
615                         GOTO(out, rc = -EINVAL);
616                 }
617
618                 rec = buf;
619                 if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
620                         lustre_swab_llog_rec(rec);
621
622                 tail = (struct llog_rec_tail *)((char *)buf + rc -
623                                                 sizeof(struct llog_rec_tail));
624                 /* get the last record in block */
625                 last_rec = (struct llog_rec_hdr *)((char *)buf + rc -
626                                                    le32_to_cpu(tail->lrt_len));
627
628                 if (LLOG_REC_HDR_NEEDS_SWABBING(last_rec))
629                         lustre_swab_llog_rec(last_rec);
630                 LASSERT(last_rec->lrh_index == tail->lrt_index);
631
632                 *cur_idx = tail->lrt_index;
633
634                 /* this shouldn't happen */
635                 if (tail->lrt_index == 0) {
636                         CERROR("%s: invalid llog tail at log id "DOSTID"/%u "
637                                "offset "LPU64"\n",
638                                o->do_lu.lo_dev->ld_obd->obd_name,
639                                POSTID(&loghandle->lgh_id.lgl_oi),
640                                loghandle->lgh_id.lgl_ogen, *cur_offset);
641                         GOTO(out, rc = -EINVAL);
642                 }
643                 if (tail->lrt_index < next_idx)
644                         continue;
645
646                 /* sanity check that the start of the new buffer is no farther
647                  * than the record that we wanted.  This shouldn't happen. */
648                 if (rec->lrh_index > next_idx) {
649                         CERROR("%s: missed desired record? %u > %u\n",
650                                o->do_lu.lo_dev->ld_obd->obd_name,
651                                rec->lrh_index, next_idx);
652                         GOTO(out, rc = -ENOENT);
653                 }
654                 GOTO(out, rc = 0);
655         }
656         GOTO(out, rc = -EIO);
657 out:
658         return rc;
659 }
660
661 static int llog_osd_prev_block(const struct lu_env *env,
662                                struct llog_handle *loghandle,
663                                int prev_idx, void *buf, int len)
664 {
665         struct llog_thread_info *lgi = llog_info(env);
666         struct dt_object        *o;
667         struct dt_device        *dt;
668         loff_t                   cur_offset;
669         int                      rc;
670
671         ENTRY;
672
673         if (len == 0 || len & (LLOG_CHUNK_SIZE - 1))
674                 RETURN(-EINVAL);
675
676         CDEBUG(D_OTHER, "looking for log index %u\n", prev_idx);
677
678         LASSERT(loghandle);
679         LASSERT(loghandle->lgh_ctxt);
680
681         o = loghandle->lgh_obj;
682         LASSERT(o);
683         LASSERT(dt_object_exists(o));
684         dt = lu2dt_dev(o->do_lu.lo_dev);
685         LASSERT(dt);
686
687         cur_offset = LLOG_CHUNK_SIZE;
688         llog_skip_over(&cur_offset, 0, prev_idx);
689
690         rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
691         if (rc)
692                 GOTO(out, rc);
693
694         while (cur_offset < lgi->lgi_attr.la_size) {
695                 struct llog_rec_hdr     *rec, *last_rec;
696                 struct llog_rec_tail    *tail;
697
698                 lgi->lgi_buf.lb_len = len;
699                 lgi->lgi_buf.lb_buf = buf;
700                 /* It is OK to have locking around dt_read() only, see
701                  * comment in llog_osd_next_block for details
702                  */
703                 dt_read_lock(env, o, 0);
704                 rc = dt_read(env, o, &lgi->lgi_buf, &cur_offset);
705                 dt_read_unlock(env, o);
706                 if (rc < 0) {
707                         CERROR("%s: can't read llog block from log "DFID
708                                " offset "LPU64": rc = %d\n",
709                                o->do_lu.lo_dev->ld_obd->obd_name,
710                                PFID(lu_object_fid(&o->do_lu)), cur_offset, rc);
711                         GOTO(out, rc);
712                 }
713
714                 if (rc == 0) /* end of file, nothing to do */
715                         GOTO(out, rc);
716
717                 if (rc < sizeof(*tail)) {
718                         CERROR("%s: invalid llog block at log id "DOSTID"/%u "
719                                "offset "LPU64"\n",
720                                o->do_lu.lo_dev->ld_obd->obd_name,
721                                POSTID(&loghandle->lgh_id.lgl_oi),
722                                loghandle->lgh_id.lgl_ogen, cur_offset);
723                         GOTO(out, rc = -EINVAL);
724                 }
725
726                 rec = buf;
727                 if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
728                         lustre_swab_llog_rec(rec);
729
730                 tail = (struct llog_rec_tail *)((char *)buf + rc -
731                                                 sizeof(struct llog_rec_tail));
732                 /* get the last record in block */
733                 last_rec = (struct llog_rec_hdr *)((char *)buf + rc -
734                                                    le32_to_cpu(tail->lrt_len));
735
736                 if (LLOG_REC_HDR_NEEDS_SWABBING(last_rec))
737                         lustre_swab_llog_rec(last_rec);
738                 LASSERT(last_rec->lrh_index == tail->lrt_index);
739
740                 /* this shouldn't happen */
741                 if (tail->lrt_index == 0) {
742                         CERROR("%s: invalid llog tail at log id "DOSTID"/%u "
743                                "offset "LPU64"\n",
744                                o->do_lu.lo_dev->ld_obd->obd_name,
745                                POSTID(&loghandle->lgh_id.lgl_oi),
746                                loghandle->lgh_id.lgl_ogen, cur_offset);
747                         GOTO(out, rc = -EINVAL);
748                 }
749                 if (tail->lrt_index < prev_idx)
750                         continue;
751
752                 /* sanity check that the start of the new buffer is no farther
753                  * than the record that we wanted.  This shouldn't happen. */
754                 if (rec->lrh_index > prev_idx) {
755                         CERROR("%s: missed desired record? %u > %u\n",
756                                o->do_lu.lo_dev->ld_obd->obd_name,
757                                rec->lrh_index, prev_idx);
758                         GOTO(out, rc = -ENOENT);
759                 }
760                 GOTO(out, rc = 0);
761         }
762         GOTO(out, rc = -EIO);
763 out:
764         return rc;
765 }
766
767 struct dt_object *llog_osd_dir_get(const struct lu_env *env,
768                                    struct llog_ctxt *ctxt)
769 {
770         struct dt_device        *dt;
771         struct dt_thread_info   *dti = dt_info(env);
772         struct dt_object        *dir;
773         int                      rc;
774
775         dt = ctxt->loc_exp->exp_obd->obd_lvfs_ctxt.dt;
776         if (ctxt->loc_dir == NULL) {
777                 rc = dt_root_get(env, dt, &dti->dti_fid);
778                 if (rc)
779                         return ERR_PTR(rc);
780                 dir = dt_locate(env, dt, &dti->dti_fid);
781         } else {
782                 lu_object_get(&ctxt->loc_dir->do_lu);
783                 dir = ctxt->loc_dir;
784         }
785
786         return dir;
787 }
788
789 static int llog_osd_open(const struct lu_env *env, struct llog_handle *handle,
790                          struct llog_logid *logid, char *name,
791                          enum llog_open_param open_param)
792 {
793         struct llog_thread_info         *lgi = llog_info(env);
794         struct llog_ctxt                *ctxt = handle->lgh_ctxt;
795         struct dt_object                *o;
796         struct dt_device                *dt;
797         struct ls_device                *ls;
798         struct local_oid_storage        *los;
799         int                              rc = 0;
800
801         ENTRY;
802
803         LASSERT(env);
804         LASSERT(ctxt);
805         LASSERT(ctxt->loc_exp);
806         LASSERT(ctxt->loc_exp->exp_obd);
807         dt = ctxt->loc_exp->exp_obd->obd_lvfs_ctxt.dt;
808         LASSERT(dt);
809
810         ls = ls_device_get(dt);
811         if (IS_ERR(ls))
812                 RETURN(PTR_ERR(ls));
813
814         mutex_lock(&ls->ls_los_mutex);
815         los = dt_los_find(ls, FID_SEQ_LLOG);
816         mutex_unlock(&ls->ls_los_mutex);
817         LASSERT(los);
818         ls_device_put(env, ls);
819
820         LASSERT(handle);
821
822         if (logid != NULL) {
823                 logid_to_fid(logid, &lgi->lgi_fid);
824         } else if (name) {
825                 struct dt_object *llog_dir;
826
827                 llog_dir = llog_osd_dir_get(env, ctxt);
828                 if (IS_ERR(llog_dir))
829                         GOTO(out, rc = PTR_ERR(llog_dir));
830                 dt_read_lock(env, llog_dir, 0);
831                 rc = dt_lookup_dir(env, llog_dir, name, &lgi->lgi_fid);
832                 dt_read_unlock(env, llog_dir);
833                 lu_object_put(env, &llog_dir->do_lu);
834                 if (rc == -ENOENT && open_param == LLOG_OPEN_NEW) {
835                         /* generate fid for new llog */
836                         rc = local_object_fid_generate(env, los,
837                                                        &lgi->lgi_fid);
838                 }
839                 if (rc < 0)
840                         GOTO(out, rc);
841                 OBD_ALLOC(handle->lgh_name, strlen(name) + 1);
842                 if (handle->lgh_name)
843                         strcpy(handle->lgh_name, name);
844                 else
845                         GOTO(out, rc = -ENOMEM);
846         } else {
847                 LASSERTF(open_param & LLOG_OPEN_NEW, "%#x\n", open_param);
848                 /* generate fid for new llog */
849                 rc = local_object_fid_generate(env, los, &lgi->lgi_fid);
850                 if (rc < 0)
851                         GOTO(out, rc);
852         }
853
854         o = ls_locate(env, ls, &lgi->lgi_fid);
855         if (IS_ERR(o))
856                 GOTO(out_name, rc = PTR_ERR(o));
857
858         /* No new llog is expected but doesn't exist */
859         if (open_param != LLOG_OPEN_NEW && !dt_object_exists(o))
860                 GOTO(out_put, rc = -ENOENT);
861
862         fid_to_logid(&lgi->lgi_fid, &handle->lgh_id);
863         handle->lgh_obj = o;
864         handle->private_data = los;
865         LASSERT(handle->lgh_ctxt);
866
867         RETURN(rc);
868
869 out_put:
870         lu_object_put(env, &o->do_lu);
871 out_name:
872         if (handle->lgh_name != NULL)
873                 OBD_FREE(handle->lgh_name, strlen(name) + 1);
874 out:
875         dt_los_put(los);
876         RETURN(rc);
877 }
878
879 static int llog_osd_exist(struct llog_handle *handle)
880 {
881         LASSERT(handle->lgh_obj);
882         return (dt_object_exists(handle->lgh_obj) &&
883                 !lu_object_is_dying(handle->lgh_obj->do_lu.lo_header));
884 }
885
886 static int llog_osd_declare_create(const struct lu_env *env,
887                                    struct llog_handle *res, struct thandle *th)
888 {
889         struct llog_thread_info         *lgi = llog_info(env);
890         struct local_oid_storage        *los;
891         struct dt_object                *o;
892         int                              rc;
893
894         ENTRY;
895
896         LASSERT(res->lgh_obj);
897         LASSERT(th);
898
899         /* object can be created by another thread */
900         o = res->lgh_obj;
901         if (dt_object_exists(o))
902                 RETURN(0);
903
904         los = res->private_data;
905         LASSERT(los);
906
907         rc = llog_osd_declare_new_object(env, los, o, th);
908         if (rc)
909                 RETURN(rc);
910
911         rc = dt_declare_record_write(env, o, LLOG_CHUNK_SIZE, 0, th);
912         if (rc)
913                 RETURN(rc);
914
915         if (res->lgh_name) {
916                 struct dt_object *llog_dir;
917
918                 llog_dir = llog_osd_dir_get(env, res->lgh_ctxt);
919                 if (IS_ERR(llog_dir))
920                         RETURN(PTR_ERR(llog_dir));
921                 dt_declare_ref_add(env, o, th);
922                 logid_to_fid(&res->lgh_id, &lgi->lgi_fid);
923                 rc = dt_declare_insert(env, llog_dir,
924                                        (struct dt_rec *)&lgi->lgi_fid,
925                                        (struct dt_key *)res->lgh_name, th);
926                 lu_object_put(env, &llog_dir->do_lu);
927                 if (rc)
928                         CERROR("%s: can't declare named llog %s: rc = %d\n",
929                                o->do_lu.lo_dev->ld_obd->obd_name,
930                                res->lgh_name, rc);
931         }
932         RETURN(rc);
933 }
934
935 /* This is a callback from the llog_* functions.
936  * Assumes caller has already pushed us into the kernel context. */
937 static int llog_osd_create(const struct lu_env *env, struct llog_handle *res,
938                            struct thandle *th)
939 {
940         struct llog_thread_info *lgi = llog_info(env);
941         struct local_oid_storage *los;
942         struct dt_object        *o;
943         int                      rc = 0;
944
945         ENTRY;
946
947         LASSERT(env);
948         o = res->lgh_obj;
949         LASSERT(o);
950
951         /* llog can be already created */
952         if (dt_object_exists(o))
953                 RETURN(-EEXIST);
954
955         los = res->private_data;
956         LASSERT(los);
957
958         dt_write_lock(env, o, 0);
959         if (!dt_object_exists(o))
960                 rc = llog_osd_create_new_object(env, los, o, th);
961         else
962                 rc = -EEXIST;
963         if (res->lgh_name)
964                 dt_ref_add(env, o, th);
965         dt_write_unlock(env, o);
966         if (rc)
967                 RETURN(rc);
968
969         if (res->lgh_name) {
970                 struct dt_object *llog_dir;
971
972                 llog_dir = llog_osd_dir_get(env, res->lgh_ctxt);
973                 if (IS_ERR(llog_dir))
974                         RETURN(PTR_ERR(llog_dir));
975
976                 logid_to_fid(&res->lgh_id, &lgi->lgi_fid);
977                 dt_read_lock(env, llog_dir, 0);
978                 rc = dt_insert(env, llog_dir,
979                                (struct dt_rec *)&lgi->lgi_fid,
980                                (struct dt_key *)res->lgh_name,
981                                th, BYPASS_CAPA, 1);
982                 dt_read_unlock(env, llog_dir);
983                 lu_object_put(env, &llog_dir->do_lu);
984                 if (rc)
985                         CERROR("%s: can't create named llog %s: rc = %d\n",
986                                o->do_lu.lo_dev->ld_obd->obd_name,
987                                res->lgh_name, rc);
988         }
989         RETURN(rc);
990 }
991
992 static int llog_osd_close(const struct lu_env *env, struct llog_handle *handle)
993 {
994         struct local_oid_storage        *los;
995         int                              rc = 0;
996
997         ENTRY;
998
999         LASSERT(handle->lgh_obj);
1000
1001         lu_object_put(env, &handle->lgh_obj->do_lu);
1002
1003         los = handle->private_data;
1004         LASSERT(los);
1005         dt_los_put(los);
1006
1007         if (handle->lgh_name)
1008                 OBD_FREE(handle->lgh_name, strlen(handle->lgh_name) + 1);
1009
1010         RETURN(rc);
1011 }
1012
1013 static int llog_osd_destroy(const struct lu_env *env,
1014                             struct llog_handle *loghandle)
1015 {
1016         struct llog_thread_info *lgi = llog_info(env);
1017         struct llog_ctxt        *ctxt;
1018         struct dt_object        *o, *llog_dir = NULL;
1019         struct dt_device        *d;
1020         struct thandle          *th;
1021         char                    *name = NULL;
1022         int                      rc;
1023
1024         ENTRY;
1025
1026         ctxt = loghandle->lgh_ctxt;
1027         LASSERT(ctxt);
1028
1029         o = loghandle->lgh_obj;
1030         LASSERT(o);
1031
1032         d = lu2dt_dev(o->do_lu.lo_dev);
1033         LASSERT(d);
1034         LASSERT(d == ctxt->loc_exp->exp_obd->obd_lvfs_ctxt.dt);
1035
1036         th = dt_trans_create(env, d);
1037         if (IS_ERR(th))
1038                 RETURN(PTR_ERR(th));
1039
1040         if (loghandle->lgh_name) {
1041                 llog_dir = llog_osd_dir_get(env, ctxt);
1042                 if (IS_ERR(llog_dir))
1043                         GOTO(out_trans, rc = PTR_ERR(llog_dir));
1044
1045                 dt_declare_ref_del(env, o, th);
1046                 name = loghandle->lgh_name;
1047                 rc = dt_declare_delete(env, llog_dir,
1048                                        (struct dt_key *)name, th);
1049                 if (rc)
1050                         GOTO(out_trans, rc);
1051         }
1052
1053         dt_declare_ref_del(env, o, th);
1054
1055         rc = dt_declare_destroy(env, o, th);
1056         if (rc)
1057                 GOTO(out_trans, rc);
1058
1059         rc = dt_trans_start_local(env, d, th);
1060         if (rc)
1061                 GOTO(out_trans, rc);
1062
1063         dt_write_lock(env, o, 0);
1064         if (dt_object_exists(o)) {
1065                 if (name) {
1066                         dt_ref_del(env, o, th);
1067                         dt_read_lock(env, llog_dir, 0);
1068                         rc = dt_delete(env, llog_dir,
1069                                        (struct dt_key *) name,
1070                                        th, BYPASS_CAPA);
1071                         dt_read_unlock(env, llog_dir);
1072                         if (rc) {
1073                                 CERROR("%s: can't remove llog %s: rc = %d\n",
1074                                        o->do_lu.lo_dev->ld_obd->obd_name,
1075                                        name, rc);
1076                                 GOTO(out_unlock, rc);
1077                         }
1078                 }
1079                 /*
1080                  * XXX: compatibility bits
1081                  *      on old filesystems llogs are referenced by the name
1082                  *      on the new ones they are referenced by OI and by
1083                  *      the name
1084                  */
1085                 rc = dt_attr_get(env, o, &lgi->lgi_attr, NULL);
1086                 if (rc)
1087                         GOTO(out_unlock, rc);
1088                 LASSERT(lgi->lgi_attr.la_nlink < 2);
1089                 if (lgi->lgi_attr.la_nlink == 1)
1090                         dt_ref_del(env, o, th);
1091                 rc = dt_destroy(env, o, th);
1092                 if (rc)
1093                         GOTO(out_unlock, rc);
1094         }
1095 out_unlock:
1096         dt_write_unlock(env, o);
1097 out_trans:
1098         dt_trans_stop(env, d, th);
1099         if (llog_dir != NULL)
1100                 lu_object_put(env, &llog_dir->do_lu);
1101         RETURN(rc);
1102 }
1103
1104 static int llog_osd_setup(const struct lu_env *env, struct obd_device *obd,
1105                           struct obd_llog_group *olg, int ctxt_idx,
1106                           struct obd_device *disk_obd)
1107 {
1108         struct local_oid_storage        *los;
1109         struct llog_thread_info         *lgi = llog_info(env);
1110         struct llog_ctxt                *ctxt;
1111         int                              rc = 0;
1112
1113         ENTRY;
1114
1115         LASSERT(obd);
1116         LASSERT(olg->olg_ctxts[ctxt_idx]);
1117
1118         ctxt = llog_ctxt_get(olg->olg_ctxts[ctxt_idx]);
1119         LASSERT(ctxt);
1120
1121         /* initialize data allowing to generate new fids,
1122          * literally we need a sequece */
1123         lgi->lgi_fid.f_seq = FID_SEQ_LLOG;
1124         lgi->lgi_fid.f_oid = 1;
1125         lgi->lgi_fid.f_ver = 0;
1126         rc = local_oid_storage_init(env, disk_obd->obd_lvfs_ctxt.dt,
1127                                     &lgi->lgi_fid, &los);
1128         llog_ctxt_put(ctxt);
1129         return rc;
1130 }
1131
1132 static int llog_osd_cleanup(const struct lu_env *env, struct llog_ctxt *ctxt)
1133 {
1134         struct dt_device                *dt;
1135         struct ls_device                *ls;
1136         struct local_oid_storage        *los;
1137
1138         LASSERT(ctxt->loc_exp->exp_obd);
1139         dt = ctxt->loc_exp->exp_obd->obd_lvfs_ctxt.dt;
1140         ls = ls_device_get(dt);
1141         if (IS_ERR(ls))
1142                 RETURN(PTR_ERR(ls));
1143
1144         mutex_lock(&ls->ls_los_mutex);
1145         los = dt_los_find(ls, FID_SEQ_LLOG);
1146         mutex_unlock(&ls->ls_los_mutex);
1147         if (los != NULL) {
1148                 dt_los_put(los);
1149                 local_oid_storage_fini(env, los);
1150         }
1151         ls_device_put(env, ls);
1152         return 0;
1153 }
1154
1155 struct llog_operations llog_osd_ops = {
1156         .lop_next_block         = llog_osd_next_block,
1157         .lop_prev_block         = llog_osd_prev_block,
1158         .lop_read_header        = llog_osd_read_header,
1159         .lop_destroy            = llog_osd_destroy,
1160         .lop_setup              = llog_osd_setup,
1161         .lop_cleanup            = llog_osd_cleanup,
1162         .lop_open               = llog_osd_open,
1163         .lop_exist              = llog_osd_exist,
1164         .lop_declare_create     = llog_osd_declare_create,
1165         .lop_create             = llog_osd_create,
1166         .lop_declare_write_rec  = llog_osd_declare_write_rec,
1167         .lop_write_rec          = llog_osd_write_rec,
1168         .lop_close              = llog_osd_close,
1169 };
1170 EXPORT_SYMBOL(llog_osd_ops);
1171
1172 /* reads the catalog list */
1173 int llog_osd_get_cat_list(const struct lu_env *env, struct dt_device *d,
1174                           int idx, int count, struct llog_catid *idarray)
1175 {
1176         struct llog_thread_info *lgi = llog_info(env);
1177         struct dt_object        *o = NULL;
1178         struct thandle          *th;
1179         int                      rc, size;
1180
1181         ENTRY;
1182
1183         LASSERT(d);
1184
1185         size = sizeof(*idarray) * count;
1186         lgi->lgi_off = idx *  sizeof(*idarray);
1187
1188         lu_local_obj_fid(&lgi->lgi_fid, LLOG_CATALOGS_OID);
1189
1190         o = dt_locate(env, d, &lgi->lgi_fid);
1191         if (IS_ERR(o))
1192                 RETURN(PTR_ERR(o));
1193
1194         if (!dt_object_exists(o)) {
1195                 th = dt_trans_create(env, d);
1196                 if (IS_ERR(th))
1197                         GOTO(out, rc = PTR_ERR(th));
1198
1199                 lgi->lgi_attr.la_valid = LA_MODE;
1200                 lgi->lgi_attr.la_mode = S_IFREG | S_IRUGO | S_IWUSR;
1201                 lgi->lgi_dof.dof_type = dt_mode_to_dft(S_IFREG);
1202
1203                 rc = dt_declare_create(env, o, &lgi->lgi_attr, NULL,
1204                                        &lgi->lgi_dof, th);
1205                 if (rc)
1206                         GOTO(out_trans, rc);
1207
1208                 rc = dt_trans_start_local(env, d, th);
1209                 if (rc)
1210                         GOTO(out_trans, rc);
1211
1212                 dt_write_lock(env, o, 0);
1213                 if (!dt_object_exists(o))
1214                         rc = dt_create(env, o, &lgi->lgi_attr, NULL,
1215                                        &lgi->lgi_dof, th);
1216                 dt_write_unlock(env, o);
1217 out_trans:
1218                 dt_trans_stop(env, d, th);
1219                 if (rc)
1220                         GOTO(out, rc);
1221         }
1222
1223         rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
1224         if (rc)
1225                 GOTO(out, rc);
1226
1227         if (!S_ISREG(lgi->lgi_attr.la_mode)) {
1228                 CERROR("%s: CATALOGS is not a regular file!: mode = %o\n",
1229                        o->do_lu.lo_dev->ld_obd->obd_name,
1230                        lgi->lgi_attr.la_mode);
1231                 GOTO(out, rc = -ENOENT);
1232         }
1233
1234         CDEBUG(D_CONFIG, "cat list: disk size=%d, read=%d\n",
1235                (int)lgi->lgi_attr.la_size, size);
1236
1237         /* return just number of llogs */
1238         if (idarray == NULL) {
1239                 rc = lgi->lgi_attr.la_size / sizeof(*idarray);
1240                 GOTO(out, rc);
1241         }
1242
1243         /* read for new ost index or for empty file */
1244         memset(idarray, 0, size);
1245         if (lgi->lgi_attr.la_size < lgi->lgi_off + size)
1246                 GOTO(out, rc = 0);
1247         if (lgi->lgi_attr.la_size < lgi->lgi_off + size)
1248                 size = lgi->lgi_attr.la_size - lgi->lgi_off;
1249
1250         lgi->lgi_buf.lb_buf = idarray;
1251         lgi->lgi_buf.lb_len = size;
1252         rc = dt_record_read(env, o, &lgi->lgi_buf, &lgi->lgi_off);
1253         if (rc) {
1254                 CERROR("%s: error reading CATALOGS: rc = %d\n",
1255                        o->do_lu.lo_dev->ld_obd->obd_name,  rc);
1256                 GOTO(out, rc);
1257         }
1258
1259         EXIT;
1260 out:
1261         lu_object_put(env, &o->do_lu);
1262         RETURN(rc);
1263 }
1264 EXPORT_SYMBOL(llog_osd_get_cat_list);
1265
1266 /* writes the cat list */
1267 int llog_osd_put_cat_list(const struct lu_env *env, struct dt_device *d,
1268                           int idx, int count, struct llog_catid *idarray)
1269 {
1270         struct llog_thread_info *lgi = llog_info(env);
1271         struct dt_object        *o = NULL;
1272         struct thandle          *th;
1273         int                      rc, size;
1274
1275         if (!count)
1276                 RETURN(0);
1277
1278         LASSERT(d);
1279
1280         size = sizeof(*idarray) * count;
1281         lgi->lgi_off = idx * sizeof(*idarray);
1282
1283         lu_local_obj_fid(&lgi->lgi_fid, LLOG_CATALOGS_OID);
1284
1285         o = dt_locate(env, d, &lgi->lgi_fid);
1286         if (IS_ERR(o))
1287                 RETURN(PTR_ERR(o));
1288
1289         if (!dt_object_exists(o))
1290                 GOTO(out, rc = -ENOENT);
1291
1292         rc = dt_attr_get(env, o, &lgi->lgi_attr, BYPASS_CAPA);
1293         if (rc)
1294                 GOTO(out, rc);
1295
1296         if (!S_ISREG(lgi->lgi_attr.la_mode)) {
1297                 CERROR("%s: CATALOGS is not a regular file!: mode = %o\n",
1298                        o->do_lu.lo_dev->ld_obd->obd_name,
1299                        lgi->lgi_attr.la_mode);
1300                 GOTO(out, rc = -ENOENT);
1301         }
1302
1303         th = dt_trans_create(env, d);
1304         if (IS_ERR(th))
1305                 GOTO(out, rc = PTR_ERR(th));
1306
1307         rc = dt_declare_record_write(env, o, size, lgi->lgi_off, th);
1308         if (rc)
1309                 GOTO(out, rc);
1310
1311         rc = dt_trans_start_local(env, d, th);
1312         if (rc)
1313                 GOTO(out_trans, rc);
1314
1315         lgi->lgi_buf.lb_buf = idarray;
1316         lgi->lgi_buf.lb_len = size;
1317         rc = dt_record_write(env, o, &lgi->lgi_buf, &lgi->lgi_off, th);
1318         if (rc)
1319                 CDEBUG(D_INODE, "error writeing CATALOGS: rc = %d\n", rc);
1320 out_trans:
1321         dt_trans_stop(env, d, th);
1322 out:
1323         lu_object_put(env, &o->do_lu);
1324         RETURN(rc);
1325 }
1326 EXPORT_SYMBOL(llog_osd_put_cat_list);