4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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.
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).
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
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
27 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2012, 2014, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * lustre/obdclass/llog.c
38 * OST<->MDS recovery logging infrastructure.
39 * Invariants in implementation:
40 * - we do not share logs among different OST<->MDS connections, so that
41 * if an OST or MDS fails it need only look at log(s) relevant to itself
43 * Author: Andreas Dilger <adilger@clusterfs.com>
44 * Author: Alex Zhuravlev <bzzz@whamcloud.com>
45 * Author: Mikhail Pershin <tappro@whamcloud.com>
48 #define DEBUG_SUBSYSTEM S_LOG
51 #include <obd_class.h>
52 #include <lustre_log.h>
53 #include "llog_internal.h"
56 * Allocate a new log or catalog handle
57 * Used inside llog_open().
59 static struct llog_handle *llog_alloc_handle(void)
61 struct llog_handle *loghandle;
63 OBD_ALLOC_PTR(loghandle);
64 if (loghandle == NULL)
67 init_rwsem(&loghandle->lgh_lock);
68 spin_lock_init(&loghandle->lgh_hdr_lock);
69 INIT_LIST_HEAD(&loghandle->u.phd.phd_entry);
70 atomic_set(&loghandle->lgh_refcount, 1);
76 * Free llog handle and header data if exists. Used in llog_close() only
78 static void llog_free_handle(struct llog_handle *loghandle)
80 LASSERT(loghandle != NULL);
82 /* failed llog_init_handle */
83 if (!loghandle->lgh_hdr)
86 if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_PLAIN)
87 LASSERT(list_empty(&loghandle->u.phd.phd_entry));
88 else if (loghandle->lgh_hdr->llh_flags & LLOG_F_IS_CAT)
89 LASSERT(list_empty(&loghandle->u.chd.chd_head));
90 LASSERT(sizeof(*(loghandle->lgh_hdr)) == LLOG_CHUNK_SIZE);
91 OBD_FREE(loghandle->lgh_hdr, LLOG_CHUNK_SIZE);
93 OBD_FREE_PTR(loghandle);
96 void llog_handle_get(struct llog_handle *loghandle)
98 atomic_inc(&loghandle->lgh_refcount);
101 void llog_handle_put(struct llog_handle *loghandle)
103 LASSERT(atomic_read(&loghandle->lgh_refcount) > 0);
104 if (atomic_dec_and_test(&loghandle->lgh_refcount))
105 llog_free_handle(loghandle);
108 /* returns negative on error; 0 if success; 1 if success & log destroyed */
109 int llog_cancel_rec(const struct lu_env *env, struct llog_handle *loghandle,
112 struct llog_log_hdr *llh = loghandle->lgh_hdr;
116 CDEBUG(D_RPCTRACE, "Canceling %d in log "DOSTID"\n",
117 index, POSTID(&loghandle->lgh_id.lgl_oi));
120 CERROR("Can't cancel index 0 which is header\n");
124 spin_lock(&loghandle->lgh_hdr_lock);
125 if (!ext2_clear_bit(index, llh->llh_bitmap)) {
126 spin_unlock(&loghandle->lgh_hdr_lock);
127 CDEBUG(D_RPCTRACE, "Catalog index %u already clear?\n", index);
133 if ((llh->llh_flags & LLOG_F_ZAP_WHEN_EMPTY) &&
134 (llh->llh_count == 1) &&
135 (loghandle->lgh_last_idx == (LLOG_BITMAP_BYTES * 8) - 1)) {
136 spin_unlock(&loghandle->lgh_hdr_lock);
137 rc = llog_destroy(env, loghandle);
139 CERROR("%s: can't destroy empty llog #"DOSTID
141 loghandle->lgh_ctxt->loc_obd->obd_name,
142 POSTID(&loghandle->lgh_id.lgl_oi),
143 loghandle->lgh_id.lgl_ogen, rc);
146 RETURN(LLOG_DEL_PLAIN);
148 spin_unlock(&loghandle->lgh_hdr_lock);
150 rc = llog_write(env, loghandle, &llh->llh_hdr, LLOG_HEADER_IDX);
152 CERROR("%s: fail to write header for llog #"DOSTID
154 loghandle->lgh_ctxt->loc_obd->obd_name,
155 POSTID(&loghandle->lgh_id.lgl_oi),
156 loghandle->lgh_id.lgl_ogen, rc);
161 spin_lock(&loghandle->lgh_hdr_lock);
162 ext2_set_bit(index, llh->llh_bitmap);
164 spin_unlock(&loghandle->lgh_hdr_lock);
167 EXPORT_SYMBOL(llog_cancel_rec);
169 static int llog_read_header(const struct lu_env *env,
170 struct llog_handle *handle,
171 struct obd_uuid *uuid)
173 struct llog_operations *lop;
176 rc = llog_handle2ops(handle, &lop);
180 if (lop->lop_read_header == NULL)
183 rc = lop->lop_read_header(env, handle);
184 if (rc == LLOG_EEMPTY) {
185 struct llog_log_hdr *llh = handle->lgh_hdr;
187 handle->lgh_last_idx = 0; /* header is record with index 0 */
188 llh->llh_count = 1; /* for the header record */
189 llh->llh_hdr.lrh_type = LLOG_HDR_MAGIC;
190 llh->llh_hdr.lrh_len = llh->llh_tail.lrt_len = LLOG_CHUNK_SIZE;
191 llh->llh_hdr.lrh_index = llh->llh_tail.lrt_index = 0;
192 llh->llh_timestamp = cfs_time_current_sec();
194 memcpy(&llh->llh_tgtuuid, uuid,
195 sizeof(llh->llh_tgtuuid));
196 llh->llh_bitmap_offset = offsetof(typeof(*llh), llh_bitmap);
197 ext2_set_bit(0, llh->llh_bitmap);
203 int llog_init_handle(const struct lu_env *env, struct llog_handle *handle,
204 int flags, struct obd_uuid *uuid)
206 struct llog_log_hdr *llh;
207 enum llog_flag fmt = flags & LLOG_F_EXT_MASK;
211 LASSERT(handle->lgh_hdr == NULL);
216 handle->lgh_hdr = llh;
217 /* first assign flags to use llog_client_ops */
218 llh->llh_flags = flags;
219 rc = llog_read_header(env, handle, uuid);
221 if (unlikely((llh->llh_flags & LLOG_F_IS_PLAIN &&
222 flags & LLOG_F_IS_CAT) ||
223 (llh->llh_flags & LLOG_F_IS_CAT &&
224 flags & LLOG_F_IS_PLAIN))) {
225 CERROR("%s: llog type is %s but initializing %s\n",
226 handle->lgh_ctxt->loc_obd->obd_name,
227 llh->llh_flags & LLOG_F_IS_CAT ?
229 flags & LLOG_F_IS_CAT ? "catalog" : "plain");
230 GOTO(out, rc = -EINVAL);
231 } else if (llh->llh_flags &
232 (LLOG_F_IS_PLAIN | LLOG_F_IS_CAT)) {
234 * it is possible to open llog without specifying llog
235 * type so it is taken from llh_flags
237 flags = llh->llh_flags;
239 /* for some reason the llh_flags has no type set */
240 CERROR("llog type is not specified!\n");
241 GOTO(out, rc = -EINVAL);
244 !obd_uuid_equals(uuid, &llh->llh_tgtuuid))) {
245 CERROR("%s: llog uuid mismatch: %s/%s\n",
246 handle->lgh_ctxt->loc_obd->obd_name,
248 (char *)llh->llh_tgtuuid.uuid);
249 GOTO(out, rc = -EEXIST);
252 if (flags & LLOG_F_IS_CAT) {
253 LASSERT(list_empty(&handle->u.chd.chd_head));
254 INIT_LIST_HEAD(&handle->u.chd.chd_head);
255 llh->llh_size = sizeof(struct llog_logid_rec);
256 } else if (!(flags & LLOG_F_IS_PLAIN)) {
257 CERROR("%s: unknown flags: %#x (expected %#x or %#x)\n",
258 handle->lgh_ctxt->loc_obd->obd_name,
259 flags, LLOG_F_IS_CAT, LLOG_F_IS_PLAIN);
262 llh->llh_flags |= fmt;
266 handle->lgh_hdr = NULL;
270 EXPORT_SYMBOL(llog_init_handle);
272 static int llog_process_thread(void *arg)
274 struct llog_process_info *lpi = arg;
275 struct llog_handle *loghandle = lpi->lpi_loghandle;
276 struct llog_log_hdr *llh = loghandle->lgh_hdr;
277 struct llog_process_cat_data *cd = lpi->lpi_catdata;
279 __u64 cur_offset = LLOG_CHUNK_SIZE;
281 int rc = 0, index = 1, last_index;
283 int last_called_index = 0;
289 OBD_ALLOC(buf, LLOG_CHUNK_SIZE);
291 lpi->lpi_rc = -ENOMEM;
296 last_called_index = cd->lpcd_first_idx;
297 index = cd->lpcd_first_idx + 1;
299 if (cd != NULL && cd->lpcd_last_idx)
300 last_index = cd->lpcd_last_idx;
302 last_index = LLOG_BITMAP_BYTES * 8 - 1;
304 if (index > last_index) {
305 /* Record is not in this buffer. */
310 struct llog_rec_hdr *rec;
312 /* skip records not set in bitmap */
313 while (index <= last_index &&
314 !ext2_test_bit(index, llh->llh_bitmap))
317 LASSERT(index <= last_index + 1);
318 if (index == last_index + 1)
321 CDEBUG(D_OTHER, "index: %d last_index %d\n",
324 /* get the buf with our target record; avoid old garbage */
325 memset(buf, 0, LLOG_CHUNK_SIZE);
326 last_offset = cur_offset;
327 rc = llog_next_block(lpi->lpi_env, loghandle, &saved_index,
328 index, &cur_offset, buf, LLOG_CHUNK_SIZE);
332 /* NB: when rec->lrh_len is accessed it is already swabbed
333 * since it is used at the "end" of the loop and the rec
334 * swabbing is done at the beginning of the loop. */
335 for (rec = (struct llog_rec_hdr *)buf;
336 (char *)rec < buf + LLOG_CHUNK_SIZE;
337 rec = llog_rec_hdr_next(rec)) {
339 CDEBUG(D_OTHER, "processing rec 0x%p type %#x\n",
342 if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
343 lustre_swab_llog_rec(rec);
345 CDEBUG(D_OTHER, "after swabbing, type=%#x idx=%d\n",
346 rec->lrh_type, rec->lrh_index);
348 if (rec->lrh_index == 0) {
349 /* probably another rec just got added? */
350 if (index <= loghandle->lgh_last_idx)
351 GOTO(repeat, rc = 0);
352 GOTO(out, rc = 0); /* no more records */
354 if (rec->lrh_len == 0 ||
355 rec->lrh_len > LLOG_CHUNK_SIZE) {
356 CWARN("invalid length %d in llog record for "
357 "index %d/%d\n", rec->lrh_len,
358 rec->lrh_index, index);
359 GOTO(out, rc = -EINVAL);
362 if (rec->lrh_index < index) {
363 CDEBUG(D_OTHER, "skipping lrh_index %d\n",
369 "lrh_index: %d lrh_len: %d (%d remains)\n",
370 rec->lrh_index, rec->lrh_len,
371 (int)(buf + LLOG_CHUNK_SIZE - (char *)rec));
373 loghandle->lgh_cur_idx = rec->lrh_index;
374 loghandle->lgh_cur_offset = (char *)rec - (char *)buf +
377 /* if set, process the callback on this record */
378 if (ext2_test_bit(index, llh->llh_bitmap)) {
379 rc = lpi->lpi_cb(lpi->lpi_env, loghandle, rec,
381 last_called_index = index;
382 if (rc == LLOG_PROC_BREAK) {
384 } else if (rc == LLOG_DEL_RECORD) {
385 rc = llog_cancel_rec(lpi->lpi_env,
392 CDEBUG(D_OTHER, "Skipped index %d\n", index);
395 /* next record, still in buffer? */
397 if (index > last_index)
404 cd->lpcd_last_idx = last_called_index;
406 if (unlikely(rc == -EIO && loghandle->lgh_obj != NULL)) {
407 /* something bad happened to the processing of a local
408 * llog file, probably I/O error or the log got corrupted..
409 * to be able to finally release the log we discard any
410 * remaining bits in the header */
411 CERROR("Local llog found corrupted\n");
412 while (index <= last_index) {
413 if (ext2_test_bit(index, llh->llh_bitmap) != 0)
414 llog_cancel_rec(lpi->lpi_env, loghandle, index);
420 OBD_FREE(buf, LLOG_CHUNK_SIZE);
425 static int llog_process_thread_daemonize(void *arg)
427 struct llog_process_info *lpi = arg;
433 /* client env has no keys, tags is just 0 */
434 rc = lu_env_init(&env, LCT_LOCAL | LCT_MG_THREAD);
439 rc = llog_process_thread(arg);
443 complete(&lpi->lpi_completion);
447 int llog_process_or_fork(const struct lu_env *env,
448 struct llog_handle *loghandle,
449 llog_cb_t cb, void *data, void *catdata, bool fork)
451 struct llog_process_info *lpi;
458 CERROR("cannot alloc pointer\n");
461 lpi->lpi_loghandle = loghandle;
463 lpi->lpi_cbdata = data;
464 lpi->lpi_catdata = catdata;
467 struct task_struct *task;
469 /* The new thread can't use parent env,
470 * init the new one in llog_process_thread_daemonize. */
472 init_completion(&lpi->lpi_completion);
473 task = kthread_run(llog_process_thread_daemonize, lpi,
474 "llog_process_thread");
477 CERROR("%s: cannot start thread: rc = %d\n",
478 loghandle->lgh_ctxt->loc_obd->obd_name, rc);
481 wait_for_completion(&lpi->lpi_completion);
484 llog_process_thread(lpi);
492 EXPORT_SYMBOL(llog_process_or_fork);
494 int llog_process(const struct lu_env *env, struct llog_handle *loghandle,
495 llog_cb_t cb, void *data, void *catdata)
498 rc = llog_process_or_fork(env, loghandle, cb, data, catdata, true);
499 return rc == LLOG_DEL_PLAIN ? 0 : rc;
501 EXPORT_SYMBOL(llog_process);
503 int llog_reverse_process(const struct lu_env *env,
504 struct llog_handle *loghandle, llog_cb_t cb,
505 void *data, void *catdata)
507 struct llog_log_hdr *llh = loghandle->lgh_hdr;
508 struct llog_process_cat_data *cd = catdata;
510 int rc = 0, first_index = 1, index, idx;
513 OBD_ALLOC(buf, LLOG_CHUNK_SIZE);
518 first_index = cd->lpcd_first_idx + 1;
519 if (cd != NULL && cd->lpcd_last_idx)
520 index = cd->lpcd_last_idx;
522 index = LLOG_BITMAP_BYTES * 8 - 1;
525 struct llog_rec_hdr *rec;
526 struct llog_rec_tail *tail;
528 /* skip records not set in bitmap */
529 while (index >= first_index &&
530 !ext2_test_bit(index, llh->llh_bitmap))
533 LASSERT(index >= first_index - 1);
534 if (index == first_index - 1)
537 /* get the buf with our target record; avoid old garbage */
538 memset(buf, 0, LLOG_CHUNK_SIZE);
539 rc = llog_prev_block(env, loghandle, index, buf,
545 idx = rec->lrh_index;
546 CDEBUG(D_RPCTRACE, "index %u : idx %u\n", index, idx);
547 while (idx < index) {
548 rec = (void *)rec + rec->lrh_len;
549 if (LLOG_REC_HDR_NEEDS_SWABBING(rec))
550 lustre_swab_llog_rec(rec);
553 LASSERT(idx == index);
554 tail = (void *)rec + rec->lrh_len - sizeof(*tail);
556 /* process records in buffer, starting where we found one */
557 while ((void *)tail > buf) {
558 if (tail->lrt_index == 0)
559 GOTO(out, rc = 0); /* no more records */
561 /* if set, process the callback on this record */
562 if (ext2_test_bit(index, llh->llh_bitmap)) {
563 rec = (void *)tail - tail->lrt_len +
566 rc = cb(env, loghandle, rec, data);
567 if (rc == LLOG_PROC_BREAK) {
569 } else if (rc == LLOG_DEL_RECORD) {
570 rc = llog_cancel_rec(env, loghandle,
577 /* previous record, still in buffer? */
579 if (index < first_index)
581 tail = (void *)tail - tail->lrt_len;
587 OBD_FREE(buf, LLOG_CHUNK_SIZE);
590 EXPORT_SYMBOL(llog_reverse_process);
596 * llog_open - open llog, may not exist
597 * llog_exist - check if llog exists
598 * llog_close - close opened llog, pair for open, frees llog_handle
599 * llog_declare_create - declare llog creation
600 * llog_create - create new llog on disk, need transaction handle
601 * llog_declare_write_rec - declaration of llog write
602 * llog_write_rec - write llog record on disk, need transaction handle
603 * llog_declare_add - declare llog catalog record addition
604 * llog_add - add llog record in catalog, need transaction handle
606 int llog_exist(struct llog_handle *loghandle)
608 struct llog_operations *lop;
613 rc = llog_handle2ops(loghandle, &lop);
616 if (lop->lop_exist == NULL)
619 rc = lop->lop_exist(loghandle);
622 EXPORT_SYMBOL(llog_exist);
624 int llog_declare_create(const struct lu_env *env,
625 struct llog_handle *loghandle, struct thandle *th)
627 struct llog_operations *lop;
632 rc = llog_handle2ops(loghandle, &lop);
635 if (lop->lop_declare_create == NULL)
638 raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
640 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
641 rc = lop->lop_declare_create(env, loghandle, th);
643 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
646 EXPORT_SYMBOL(llog_declare_create);
648 int llog_create(const struct lu_env *env, struct llog_handle *handle,
651 struct llog_operations *lop;
656 rc = llog_handle2ops(handle, &lop);
659 if (lop->lop_create == NULL)
662 raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
664 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
665 rc = lop->lop_create(env, handle, th);
667 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
670 EXPORT_SYMBOL(llog_create);
672 int llog_declare_write_rec(const struct lu_env *env,
673 struct llog_handle *handle,
674 struct llog_rec_hdr *rec, int idx,
677 struct llog_operations *lop;
682 rc = llog_handle2ops(handle, &lop);
686 if (lop->lop_declare_write_rec == NULL)
689 raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
691 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
692 rc = lop->lop_declare_write_rec(env, handle, rec, idx, th);
694 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
697 EXPORT_SYMBOL(llog_declare_write_rec);
699 int llog_write_rec(const struct lu_env *env, struct llog_handle *handle,
700 struct llog_rec_hdr *rec, struct llog_cookie *logcookies,
701 int idx, struct thandle *th)
703 struct llog_operations *lop;
704 int raised, rc, buflen;
708 rc = llog_handle2ops(handle, &lop);
713 if (lop->lop_write_rec == NULL)
716 buflen = rec->lrh_len;
717 LASSERT(cfs_size_round(buflen) == buflen);
719 raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
721 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
722 rc = lop->lop_write_rec(env, handle, rec, logcookies, idx, th);
724 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
727 EXPORT_SYMBOL(llog_write_rec);
729 int llog_add(const struct lu_env *env, struct llog_handle *lgh,
730 struct llog_rec_hdr *rec, struct llog_cookie *logcookies,
737 if (lgh->lgh_logops->lop_add == NULL)
740 raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
742 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
743 rc = lgh->lgh_logops->lop_add(env, lgh, rec, logcookies, th);
745 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
748 EXPORT_SYMBOL(llog_add);
750 int llog_declare_add(const struct lu_env *env, struct llog_handle *lgh,
751 struct llog_rec_hdr *rec, struct thandle *th)
757 if (lgh->lgh_logops->lop_declare_add == NULL)
760 raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
762 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
763 rc = lgh->lgh_logops->lop_declare_add(env, lgh, rec, th);
765 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
768 EXPORT_SYMBOL(llog_declare_add);
771 * Helper function to open llog or create it if doesn't exist.
772 * It hides all transaction handling from caller.
774 int llog_open_create(const struct lu_env *env, struct llog_ctxt *ctxt,
775 struct llog_handle **res, struct llog_logid *logid,
784 rc = llog_open(env, ctxt, res, logid, name, LLOG_OPEN_NEW);
788 if (llog_exist(*res))
791 LASSERT((*res)->lgh_obj != NULL);
793 d = lu2dt_dev((*res)->lgh_obj->do_lu.lo_dev);
795 th = dt_trans_create(env, d);
797 GOTO(out, rc = PTR_ERR(th));
799 rc = llog_declare_create(env, *res, th);
801 rc = dt_trans_start_local(env, d, th);
803 rc = llog_create(env, *res, th);
805 dt_trans_stop(env, d, th);
808 llog_close(env, *res);
811 EXPORT_SYMBOL(llog_open_create);
814 * Helper function to delete existent llog.
816 int llog_erase(const struct lu_env *env, struct llog_ctxt *ctxt,
817 struct llog_logid *logid, char *name)
819 struct llog_handle *handle;
824 /* nothing to erase */
825 if (name == NULL && logid == NULL)
828 rc = llog_open(env, ctxt, &handle, logid, name, LLOG_OPEN_EXISTS);
832 rc = llog_init_handle(env, handle, LLOG_F_IS_PLAIN, NULL);
834 rc = llog_destroy(env, handle);
836 rc2 = llog_close(env, handle);
841 EXPORT_SYMBOL(llog_erase);
844 * Helper function for write record in llog.
845 * It hides all transaction handling from caller.
846 * Valid only with local llog.
848 int llog_write(const struct lu_env *env, struct llog_handle *loghandle,
849 struct llog_rec_hdr *rec, int idx)
851 struct dt_device *dt;
858 LASSERT(loghandle->lgh_ctxt);
859 LASSERT(loghandle->lgh_obj != NULL);
861 dt = lu2dt_dev(loghandle->lgh_obj->do_lu.lo_dev);
863 th = dt_trans_create(env, dt);
867 rc = llog_declare_write_rec(env, loghandle, rec, idx, th);
871 rc = dt_trans_start_local(env, dt, th);
875 down_write(&loghandle->lgh_lock);
876 rc = llog_write_rec(env, loghandle, rec, NULL, idx, th);
877 up_write(&loghandle->lgh_lock);
879 dt_trans_stop(env, dt, th);
882 EXPORT_SYMBOL(llog_write);
884 int llog_open(const struct lu_env *env, struct llog_ctxt *ctxt,
885 struct llog_handle **lgh, struct llog_logid *logid,
886 char *name, enum llog_open_param open_param)
894 LASSERT(ctxt->loc_logops);
896 if (ctxt->loc_logops->lop_open == NULL) {
901 *lgh = llog_alloc_handle();
904 (*lgh)->lgh_ctxt = ctxt;
905 (*lgh)->lgh_logops = ctxt->loc_logops;
907 raised = cfs_cap_raised(CFS_CAP_SYS_RESOURCE);
909 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
910 rc = ctxt->loc_logops->lop_open(env, *lgh, logid, name, open_param);
912 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
914 llog_free_handle(*lgh);
919 EXPORT_SYMBOL(llog_open);
921 int llog_close(const struct lu_env *env, struct llog_handle *loghandle)
923 struct llog_operations *lop;
928 rc = llog_handle2ops(loghandle, &lop);
931 if (lop->lop_close == NULL)
932 GOTO(out, rc = -EOPNOTSUPP);
933 rc = lop->lop_close(env, loghandle);
935 llog_handle_put(loghandle);
938 EXPORT_SYMBOL(llog_close);
941 * Helper function to get the llog size in records. It is used by MGS
942 * mostly to check that config llog exists and contains data.
944 * \param[in] env execution environment
945 * \param[in] ctxt llog context
946 * \param[in] name llog name
948 * \retval true if there are records in llog besides a header
949 * \retval false on error or llog without records
951 int llog_is_empty(const struct lu_env *env, struct llog_ctxt *ctxt,
954 struct llog_handle *llh;
957 rc = llog_open(env, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
959 if (likely(rc == -ENOENT))
964 rc = llog_init_handle(env, llh, LLOG_F_IS_PLAIN, NULL);
967 rc = llog_get_size(llh);
970 llog_close(env, llh);
972 /* The header is record 1, the llog is still considered as empty
973 * if there is only header */
976 EXPORT_SYMBOL(llog_is_empty);
978 int llog_copy_handler(const struct lu_env *env, struct llog_handle *llh,
979 struct llog_rec_hdr *rec, void *data)
981 struct llog_handle *copy_llh = data;
983 /* Append all records */
984 return llog_write(env, copy_llh, rec, LLOG_NEXT_IDX);
986 EXPORT_SYMBOL(llog_copy_handler);
988 /* backup plain llog */
989 int llog_backup(const struct lu_env *env, struct obd_device *obd,
990 struct llog_ctxt *ctxt, struct llog_ctxt *bctxt,
991 char *name, char *backup)
993 struct llog_handle *llh, *bllh;
998 /* open original log */
999 rc = llog_open(env, ctxt, &llh, NULL, name, LLOG_OPEN_EXISTS);
1001 /* the -ENOENT case is also reported to the caller
1002 * but silently so it should handle that if needed.
1005 CERROR("%s: failed to open log %s: rc = %d\n",
1006 obd->obd_name, name, rc);
1010 rc = llog_init_handle(env, llh, LLOG_F_IS_PLAIN, NULL);
1012 GOTO(out_close, rc);
1014 /* Make sure there's no old backup log */
1015 rc = llog_erase(env, bctxt, NULL, backup);
1016 if (rc < 0 && rc != -ENOENT)
1017 GOTO(out_close, rc);
1019 /* open backup log */
1020 rc = llog_open_create(env, bctxt, &bllh, NULL, backup);
1022 CERROR("%s: failed to open backup logfile %s: rc = %d\n",
1023 obd->obd_name, backup, rc);
1024 GOTO(out_close, rc);
1027 /* check that backup llog is not the same object as original one */
1028 if (llh->lgh_obj == bllh->lgh_obj) {
1029 CERROR("%s: backup llog %s to itself (%s), objects %p/%p\n",
1030 obd->obd_name, name, backup, llh->lgh_obj,
1032 GOTO(out_backup, rc = -EEXIST);
1035 rc = llog_init_handle(env, bllh, LLOG_F_IS_PLAIN, NULL);
1037 GOTO(out_backup, rc);
1039 /* Copy log record by record */
1040 rc = llog_process_or_fork(env, llh, llog_copy_handler, (void *)bllh,
1043 CERROR("%s: failed to backup log %s: rc = %d\n",
1044 obd->obd_name, name, rc);
1046 llog_close(env, bllh);
1048 llog_close(env, llh);
1051 EXPORT_SYMBOL(llog_backup);