2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/gfs2_ondisk.h>
16 #include <linux/lm_interface.h>
30 static void glock_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
32 struct gfs2_glock *gl;
33 struct gfs2_trans *tr = current->journal_info;
37 gl = container_of(le, struct gfs2_glock, gl_le);
38 if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(gl)))
42 if (!list_empty(&le->le_list)){
47 set_bit(GLF_DIRTY, &gl->gl_flags);
49 list_add(&le->le_list, &sdp->sd_log_le_gl);
53 static void glock_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
55 struct list_head *head = &sdp->sd_log_le_gl;
56 struct gfs2_glock *gl;
58 while (!list_empty(head)) {
59 gl = list_entry(head->next, struct gfs2_glock, gl_le.le_list);
60 list_del_init(&gl->gl_le.le_list);
63 gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(gl));
66 gfs2_assert_warn(sdp, !sdp->sd_log_num_gl);
69 static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
71 struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
72 struct gfs2_trans *tr;
75 if (!list_empty(&bd->bd_list_tr)) {
79 tr = current->journal_info;
82 list_add(&bd->bd_list_tr, &tr->tr_list_buf);
85 if (!list_empty(&le->le_list))
88 gfs2_trans_add_gl(bd->bd_gl);
90 gfs2_meta_check(sdp, bd->bd_bh);
91 gfs2_pin(sdp, bd->bd_bh);
93 sdp->sd_log_num_buf++;
94 list_add(&le->le_list, &sdp->sd_log_le_buf);
100 static void buf_lo_incore_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
102 struct list_head *head = &tr->tr_list_buf;
103 struct gfs2_bufdata *bd;
106 while (!list_empty(head)) {
107 bd = list_entry(head->next, struct gfs2_bufdata, bd_list_tr);
108 list_del_init(&bd->bd_list_tr);
111 gfs2_log_unlock(sdp);
112 gfs2_assert_warn(sdp, !tr->tr_num_buf);
115 static void buf_lo_before_commit(struct gfs2_sbd *sdp)
117 struct buffer_head *bh;
118 struct gfs2_log_descriptor *ld;
119 struct gfs2_bufdata *bd1 = NULL, *bd2;
121 unsigned int offset = BUF_OFFSET;
127 limit = buf_limit(sdp);
128 /* for 4k blocks, limit = 503 */
131 total = sdp->sd_log_num_buf;
132 bd1 = bd2 = list_prepare_entry(bd1, &sdp->sd_log_le_buf, bd_le.le_list);
137 gfs2_log_unlock(sdp);
138 bh = gfs2_log_get_buf(sdp);
140 ld = (struct gfs2_log_descriptor *)bh->b_data;
141 ptr = (__be64 *)(bh->b_data + offset);
142 ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
143 ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
144 ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
145 ld->ld_type = cpu_to_be32(GFS2_LOG_DESC_METADATA);
146 ld->ld_length = cpu_to_be32(num + 1);
147 ld->ld_data1 = cpu_to_be32(num);
148 ld->ld_data2 = cpu_to_be32(0);
149 memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved));
152 list_for_each_entry_continue(bd1, &sdp->sd_log_le_buf,
154 *ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr);
159 gfs2_log_unlock(sdp);
160 set_buffer_dirty(bh);
161 ll_rw_block(WRITE, 1, &bh);
165 list_for_each_entry_continue(bd2, &sdp->sd_log_le_buf,
167 gfs2_log_unlock(sdp);
168 bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
169 set_buffer_dirty(bh);
170 ll_rw_block(WRITE, 1, &bh);
179 gfs2_log_unlock(sdp);
182 static void buf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
184 struct list_head *head = &sdp->sd_log_le_buf;
185 struct gfs2_bufdata *bd;
187 while (!list_empty(head)) {
188 bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
189 list_del_init(&bd->bd_le.le_list);
190 sdp->sd_log_num_buf--;
192 gfs2_unpin(sdp, bd->bd_bh, ai);
194 gfs2_assert_warn(sdp, !sdp->sd_log_num_buf);
197 static void buf_lo_before_scan(struct gfs2_jdesc *jd,
198 struct gfs2_log_header_host *head, int pass)
200 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
205 sdp->sd_found_blocks = 0;
206 sdp->sd_replayed_blocks = 0;
209 static int buf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
210 struct gfs2_log_descriptor *ld, __be64 *ptr,
213 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
214 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
215 struct gfs2_glock *gl = ip->i_gl;
216 unsigned int blks = be32_to_cpu(ld->ld_data1);
217 struct buffer_head *bh_log, *bh_ip;
221 if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_METADATA)
224 gfs2_replay_incr_blk(sdp, &start);
226 for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
227 blkno = be64_to_cpu(*ptr++);
229 sdp->sd_found_blocks++;
231 if (gfs2_revoke_check(sdp, blkno, start))
234 error = gfs2_replay_read_block(jd, start, &bh_log);
238 bh_ip = gfs2_meta_new(gl, blkno);
239 memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
241 if (gfs2_meta_check(sdp, bh_ip))
244 mark_buffer_dirty(bh_ip);
252 sdp->sd_replayed_blocks++;
258 static void buf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
260 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
261 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
264 gfs2_meta_sync(ip->i_gl);
270 gfs2_meta_sync(ip->i_gl);
272 fs_info(sdp, "jid=%u: Replayed %u of %u blocks\n",
273 jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
276 static void revoke_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
278 struct gfs2_trans *tr;
280 tr = current->journal_info;
285 sdp->sd_log_num_revoke++;
286 list_add(&le->le_list, &sdp->sd_log_le_revoke);
287 gfs2_log_unlock(sdp);
290 static void revoke_lo_before_commit(struct gfs2_sbd *sdp)
292 struct gfs2_log_descriptor *ld;
293 struct gfs2_meta_header *mh;
294 struct buffer_head *bh;
296 struct list_head *head = &sdp->sd_log_le_revoke;
297 struct gfs2_revoke *rv;
299 if (!sdp->sd_log_num_revoke)
302 bh = gfs2_log_get_buf(sdp);
303 ld = (struct gfs2_log_descriptor *)bh->b_data;
304 ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
305 ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
306 ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
307 ld->ld_type = cpu_to_be32(GFS2_LOG_DESC_REVOKE);
308 ld->ld_length = cpu_to_be32(gfs2_struct2blk(sdp, sdp->sd_log_num_revoke,
310 ld->ld_data1 = cpu_to_be32(sdp->sd_log_num_revoke);
311 ld->ld_data2 = cpu_to_be32(0);
312 memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved));
313 offset = sizeof(struct gfs2_log_descriptor);
315 while (!list_empty(head)) {
316 rv = list_entry(head->next, struct gfs2_revoke, rv_le.le_list);
317 list_del_init(&rv->rv_le.le_list);
318 sdp->sd_log_num_revoke--;
320 if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) {
321 set_buffer_dirty(bh);
322 ll_rw_block(WRITE, 1, &bh);
324 bh = gfs2_log_get_buf(sdp);
325 mh = (struct gfs2_meta_header *)bh->b_data;
326 mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
327 mh->mh_type = cpu_to_be32(GFS2_METATYPE_LB);
328 mh->mh_format = cpu_to_be32(GFS2_FORMAT_LB);
329 offset = sizeof(struct gfs2_meta_header);
332 *(__be64 *)(bh->b_data + offset) = cpu_to_be64(rv->rv_blkno);
335 offset += sizeof(u64);
337 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
339 set_buffer_dirty(bh);
340 ll_rw_block(WRITE, 1, &bh);
343 static void revoke_lo_before_scan(struct gfs2_jdesc *jd,
344 struct gfs2_log_header_host *head, int pass)
346 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
351 sdp->sd_found_revokes = 0;
352 sdp->sd_replay_tail = head->lh_tail;
355 static int revoke_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
356 struct gfs2_log_descriptor *ld, __be64 *ptr,
359 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
360 unsigned int blks = be32_to_cpu(ld->ld_length);
361 unsigned int revokes = be32_to_cpu(ld->ld_data1);
362 struct buffer_head *bh;
368 if (pass != 0 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_REVOKE)
371 offset = sizeof(struct gfs2_log_descriptor);
373 for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
374 error = gfs2_replay_read_block(jd, start, &bh);
379 gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LB);
381 while (offset + sizeof(u64) <= sdp->sd_sb.sb_bsize) {
382 blkno = be64_to_cpu(*(__be64 *)(bh->b_data + offset));
384 error = gfs2_revoke_add(sdp, blkno, start);
388 sdp->sd_found_revokes++;
392 offset += sizeof(u64);
396 offset = sizeof(struct gfs2_meta_header);
403 static void revoke_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
405 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
408 gfs2_revoke_clean(sdp);
414 fs_info(sdp, "jid=%u: Found %u revoke tags\n",
415 jd->jd_jid, sdp->sd_found_revokes);
417 gfs2_revoke_clean(sdp);
420 static void rg_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
422 struct gfs2_rgrpd *rgd;
423 struct gfs2_trans *tr = current->journal_info;
427 rgd = container_of(le, struct gfs2_rgrpd, rd_le);
430 if (!list_empty(&le->le_list)){
431 gfs2_log_unlock(sdp);
434 gfs2_rgrp_bh_hold(rgd);
435 sdp->sd_log_num_rg++;
436 list_add(&le->le_list, &sdp->sd_log_le_rg);
437 gfs2_log_unlock(sdp);
440 static void rg_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
442 struct list_head *head = &sdp->sd_log_le_rg;
443 struct gfs2_rgrpd *rgd;
445 while (!list_empty(head)) {
446 rgd = list_entry(head->next, struct gfs2_rgrpd, rd_le.le_list);
447 list_del_init(&rgd->rd_le.le_list);
448 sdp->sd_log_num_rg--;
450 gfs2_rgrp_repolish_clones(rgd);
451 gfs2_rgrp_bh_put(rgd);
453 gfs2_assert_warn(sdp, !sdp->sd_log_num_rg);
457 * databuf_lo_add - Add a databuf to the transaction.
459 * This is used in two distinct cases:
460 * i) In ordered write mode
461 * We put the data buffer on a list so that we can ensure that its
462 * synced to disk at the right time
463 * ii) In journaled data mode
464 * We need to journal the data block in the same way as metadata in
465 * the functions above. The difference is that here we have a tag
466 * which is two __be64's being the block number (as per meta data)
467 * and a flag which says whether the data block needs escaping or
468 * not. This means we need a new log entry for each 251 or so data
469 * blocks, which isn't an enormous overhead but twice as much as
470 * for normal metadata blocks.
472 static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
474 struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
475 struct gfs2_trans *tr = current->journal_info;
476 struct address_space *mapping = bd->bd_bh->b_page->mapping;
477 struct gfs2_inode *ip = GFS2_I(mapping->host);
480 if (!list_empty(&bd->bd_list_tr)) {
481 gfs2_log_unlock(sdp);
485 if (gfs2_is_jdata(ip)) {
487 list_add(&bd->bd_list_tr, &tr->tr_list_buf);
489 gfs2_log_unlock(sdp);
490 if (!list_empty(&le->le_list))
493 gfs2_trans_add_gl(bd->bd_gl);
494 if (gfs2_is_jdata(ip)) {
495 gfs2_pin(sdp, bd->bd_bh);
496 tr->tr_num_databuf_new++;
499 if (gfs2_is_jdata(ip))
500 sdp->sd_log_num_jdata++;
501 sdp->sd_log_num_databuf++;
502 list_add(&le->le_list, &sdp->sd_log_le_databuf);
503 gfs2_log_unlock(sdp);
506 static int gfs2_check_magic(struct buffer_head *bh)
508 struct page *page = bh->b_page;
513 kaddr = kmap_atomic(page, KM_USER0);
514 ptr = kaddr + bh_offset(bh);
515 if (*ptr == cpu_to_be32(GFS2_MAGIC))
517 kunmap_atomic(kaddr, KM_USER0);
523 * databuf_lo_before_commit - Scan the data buffers, writing as we go
525 * Here we scan through the lists of buffers and make the assumption
526 * that any buffer thats been pinned is being journaled, and that
527 * any unpinned buffer is an ordered write data buffer and therefore
528 * will be written back rather than journaled.
530 static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
533 struct gfs2_bufdata *bd1 = NULL, *bd2, *bdt;
534 struct buffer_head *bh = NULL,*bh1 = NULL;
535 struct gfs2_log_descriptor *ld;
537 unsigned int total_dbuf;
538 unsigned int total_jdata;
542 limit = databuf_limit(sdp);
545 * Start writing ordered buffers, write journaled buffers
546 * into the log along with a header
549 total_dbuf = sdp->sd_log_num_databuf;
550 total_jdata = sdp->sd_log_num_jdata;
551 bd2 = bd1 = list_prepare_entry(bd1, &sdp->sd_log_le_databuf,
558 list_for_each_entry_safe_continue(bd1, bdt,
559 &sdp->sd_log_le_databuf,
561 /* store off the buffer head in a local ptr since
562 * gfs2_bufdata might change when we drop the log lock
566 /* An ordered write buffer */
567 if (bh1 && !buffer_pinned(bh1)) {
568 list_move(&bd1->bd_le.le_list, &started);
571 bd2 = list_prepare_entry(bd2,
572 &sdp->sd_log_le_databuf,
577 if (buffer_dirty(bh1)) {
580 gfs2_log_unlock(sdp);
582 ll_rw_block(SWRITE, 1, &bh1);
590 } else if (bh1) { /* A journaled buffer */
592 gfs2_log_unlock(sdp);
594 bh = gfs2_log_get_buf(sdp);
595 ld = (struct gfs2_log_descriptor *)
597 ptr = (__be64 *)(bh->b_data +
599 ld->ld_header.mh_magic =
600 cpu_to_be32(GFS2_MAGIC);
601 ld->ld_header.mh_type =
602 cpu_to_be32(GFS2_METATYPE_LD);
603 ld->ld_header.mh_format =
604 cpu_to_be32(GFS2_FORMAT_LD);
606 cpu_to_be32(GFS2_LOG_DESC_JDATA);
607 ld->ld_length = cpu_to_be32(num + 1);
608 ld->ld_data1 = cpu_to_be32(num);
609 ld->ld_data2 = cpu_to_be32(0);
610 memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved));
612 magic = gfs2_check_magic(bh1);
613 *ptr++ = cpu_to_be64(bh1->b_blocknr);
614 *ptr++ = cpu_to_be64((__u64)magic);
615 clear_buffer_escaped(bh1);
616 if (unlikely(magic != 0))
617 set_buffer_escaped(bh1);
623 sdp->sd_log_num_databuf--;
624 list_del_init(&bd1->bd_le.le_list);
627 bd2 = list_prepare_entry(bd2,
628 &sdp->sd_log_le_databuf,
631 kmem_cache_free(gfs2_bufdata_cachep, bd1);
634 gfs2_log_unlock(sdp);
636 set_buffer_dirty(bh);
637 ll_rw_block(WRITE, 1, &bh);
643 list_for_each_entry_continue(bd2, &sdp->sd_log_le_databuf,
647 /* copy buffer if it needs escaping */
648 gfs2_log_unlock(sdp);
649 if (unlikely(buffer_escaped(bd2->bd_bh))) {
651 struct page *page = bd2->bd_bh->b_page;
652 bh = gfs2_log_get_buf(sdp);
653 kaddr = kmap_atomic(page, KM_USER0);
655 kaddr + bh_offset(bd2->bd_bh),
656 sdp->sd_sb.sb_bsize);
657 kunmap_atomic(kaddr, KM_USER0);
658 *(__be32 *)bh->b_data = 0;
660 bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
662 set_buffer_dirty(bh);
663 ll_rw_block(WRITE, 1, &bh);
669 BUG_ON(total_dbuf < num);
673 gfs2_log_unlock(sdp);
675 /* Wait on all ordered buffers */
676 while (!list_empty(&started)) {
678 bd1 = list_entry(started.next, struct gfs2_bufdata,
680 list_del_init(&bd1->bd_le.le_list);
681 sdp->sd_log_num_databuf--;
684 bh->b_private = NULL;
686 gfs2_log_unlock(sdp);
690 gfs2_log_unlock(sdp);
692 kmem_cache_free(gfs2_bufdata_cachep, bd1);
695 /* We've removed all the ordered write bufs here, so only jdata left */
696 gfs2_assert_warn(sdp, sdp->sd_log_num_databuf == sdp->sd_log_num_jdata);
699 static int databuf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
700 struct gfs2_log_descriptor *ld,
701 __be64 *ptr, int pass)
703 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
704 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
705 struct gfs2_glock *gl = ip->i_gl;
706 unsigned int blks = be32_to_cpu(ld->ld_data1);
707 struct buffer_head *bh_log, *bh_ip;
712 if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_JDATA)
715 gfs2_replay_incr_blk(sdp, &start);
716 for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
717 blkno = be64_to_cpu(*ptr++);
718 esc = be64_to_cpu(*ptr++);
720 sdp->sd_found_blocks++;
722 if (gfs2_revoke_check(sdp, blkno, start))
725 error = gfs2_replay_read_block(jd, start, &bh_log);
729 bh_ip = gfs2_meta_new(gl, blkno);
730 memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
734 __be32 *eptr = (__be32 *)bh_ip->b_data;
735 *eptr = cpu_to_be32(GFS2_MAGIC);
737 mark_buffer_dirty(bh_ip);
744 sdp->sd_replayed_blocks++;
750 /* FIXME: sort out accounting for log blocks etc. */
752 static void databuf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
754 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
755 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
758 gfs2_meta_sync(ip->i_gl);
765 gfs2_meta_sync(ip->i_gl);
767 fs_info(sdp, "jid=%u: Replayed %u of %u data blocks\n",
768 jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
771 static void databuf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
773 struct list_head *head = &sdp->sd_log_le_databuf;
774 struct gfs2_bufdata *bd;
776 while (!list_empty(head)) {
777 bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
778 list_del_init(&bd->bd_le.le_list);
779 sdp->sd_log_num_databuf--;
780 sdp->sd_log_num_jdata--;
781 gfs2_unpin(sdp, bd->bd_bh, ai);
783 gfs2_assert_warn(sdp, !sdp->sd_log_num_databuf);
784 gfs2_assert_warn(sdp, !sdp->sd_log_num_jdata);
788 const struct gfs2_log_operations gfs2_glock_lops = {
789 .lo_add = glock_lo_add,
790 .lo_after_commit = glock_lo_after_commit,
794 const struct gfs2_log_operations gfs2_buf_lops = {
795 .lo_add = buf_lo_add,
796 .lo_incore_commit = buf_lo_incore_commit,
797 .lo_before_commit = buf_lo_before_commit,
798 .lo_after_commit = buf_lo_after_commit,
799 .lo_before_scan = buf_lo_before_scan,
800 .lo_scan_elements = buf_lo_scan_elements,
801 .lo_after_scan = buf_lo_after_scan,
805 const struct gfs2_log_operations gfs2_revoke_lops = {
806 .lo_add = revoke_lo_add,
807 .lo_before_commit = revoke_lo_before_commit,
808 .lo_before_scan = revoke_lo_before_scan,
809 .lo_scan_elements = revoke_lo_scan_elements,
810 .lo_after_scan = revoke_lo_after_scan,
814 const struct gfs2_log_operations gfs2_rg_lops = {
816 .lo_after_commit = rg_lo_after_commit,
820 const struct gfs2_log_operations gfs2_databuf_lops = {
821 .lo_add = databuf_lo_add,
822 .lo_incore_commit = buf_lo_incore_commit,
823 .lo_before_commit = databuf_lo_before_commit,
824 .lo_after_commit = databuf_lo_after_commit,
825 .lo_scan_elements = databuf_lo_scan_elements,
826 .lo_after_scan = databuf_lo_after_scan,
827 .lo_name = "databuf",
830 const struct gfs2_log_operations *gfs2_log_ops[] = {