2 * segment.c - NILFS segment constructor.
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
24 #include <linux/pagemap.h>
25 #include <linux/buffer_head.h>
26 #include <linux/writeback.h>
27 #include <linux/bio.h>
28 #include <linux/completion.h>
29 #include <linux/blkdev.h>
30 #include <linux/backing-dev.h>
31 #include <linux/freezer.h>
32 #include <linux/kthread.h>
33 #include <linux/crc32.h>
34 #include <linux/pagevec.h>
35 #include <linux/slab.h>
49 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
51 #define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments
52 appended in collection retry loop */
54 /* Construction mode */
56 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
57 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make
58 a logical segment without a super root */
59 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without
60 creating a checkpoint */
61 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without
65 /* Stage numbers of dirty block collection */
68 NILFS_ST_GC, /* Collecting dirty blocks for GC */
74 NILFS_ST_SR, /* Super root */
75 NILFS_ST_DSYNC, /* Data sync blocks */
79 /* State flags of collection */
80 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
81 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
82 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
83 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
85 /* Operations depending on the construction mode and file type */
86 struct nilfs_sc_operations {
87 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
89 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
91 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
93 void (*write_data_binfo)(struct nilfs_sc_info *,
94 struct nilfs_segsum_pointer *,
96 void (*write_node_binfo)(struct nilfs_sc_info *,
97 struct nilfs_segsum_pointer *,
104 static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
105 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
106 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
107 static void nilfs_dispose_list(struct nilfs_sb_info *, struct list_head *,
110 #define nilfs_cnt32_gt(a, b) \
111 (typecheck(__u32, a) && typecheck(__u32, b) && \
112 ((__s32)(b) - (__s32)(a) < 0))
113 #define nilfs_cnt32_ge(a, b) \
114 (typecheck(__u32, a) && typecheck(__u32, b) && \
115 ((__s32)(a) - (__s32)(b) >= 0))
116 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
117 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
119 static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
121 struct nilfs_transaction_info *cur_ti = current->journal_info;
125 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
126 return ++cur_ti->ti_count;
129 * If journal_info field is occupied by other FS,
130 * it is saved and will be restored on
131 * nilfs_transaction_commit().
134 "NILFS warning: journal info from a different "
136 save = current->journal_info;
140 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
143 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
149 ti->ti_magic = NILFS_TI_MAGIC;
150 current->journal_info = ti;
155 * nilfs_transaction_begin - start indivisible file operations.
157 * @ti: nilfs_transaction_info
158 * @vacancy_check: flags for vacancy rate checks
160 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
161 * the segment semaphore, to make a segment construction and write tasks
162 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
163 * The region enclosed by these two functions can be nested. To avoid a
164 * deadlock, the semaphore is only acquired or released in the outermost call.
166 * This function allocates a nilfs_transaction_info struct to keep context
167 * information on it. It is initialized and hooked onto the current task in
168 * the outermost call. If a pre-allocated struct is given to @ti, it is used
169 * instead; otherwise a new struct is assigned from a slab.
171 * When @vacancy_check flag is set, this function will check the amount of
172 * free space, and will wait for the GC to reclaim disk space if low capacity.
174 * Return Value: On success, 0 is returned. On error, one of the following
175 * negative error code is returned.
177 * %-ENOMEM - Insufficient memory available.
179 * %-ENOSPC - No space left on device
181 int nilfs_transaction_begin(struct super_block *sb,
182 struct nilfs_transaction_info *ti,
185 struct nilfs_sb_info *sbi;
186 struct the_nilfs *nilfs;
187 int ret = nilfs_prepare_segment_lock(ti);
189 if (unlikely(ret < 0))
194 vfs_check_frozen(sb, SB_FREEZE_WRITE);
197 nilfs = sbi->s_nilfs;
198 down_read(&nilfs->ns_segctor_sem);
199 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
200 up_read(&nilfs->ns_segctor_sem);
207 ti = current->journal_info;
208 current->journal_info = ti->ti_save;
209 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
210 kmem_cache_free(nilfs_transaction_cachep, ti);
215 * nilfs_transaction_commit - commit indivisible file operations.
218 * nilfs_transaction_commit() releases the read semaphore which is
219 * acquired by nilfs_transaction_begin(). This is only performed
220 * in outermost call of this function. If a commit flag is set,
221 * nilfs_transaction_commit() sets a timer to start the segment
222 * constructor. If a sync flag is set, it starts construction
225 int nilfs_transaction_commit(struct super_block *sb)
227 struct nilfs_transaction_info *ti = current->journal_info;
228 struct nilfs_sb_info *sbi;
229 struct nilfs_sc_info *sci;
232 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
233 ti->ti_flags |= NILFS_TI_COMMIT;
234 if (ti->ti_count > 0) {
241 if (ti->ti_flags & NILFS_TI_COMMIT)
242 nilfs_segctor_start_timer(sci);
243 if (atomic_read(&sbi->s_nilfs->ns_ndirtyblks) >
245 nilfs_segctor_do_flush(sci, 0);
247 up_read(&sbi->s_nilfs->ns_segctor_sem);
248 current->journal_info = ti->ti_save;
250 if (ti->ti_flags & NILFS_TI_SYNC)
251 err = nilfs_construct_segment(sb);
252 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
253 kmem_cache_free(nilfs_transaction_cachep, ti);
257 void nilfs_transaction_abort(struct super_block *sb)
259 struct nilfs_transaction_info *ti = current->journal_info;
261 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
262 if (ti->ti_count > 0) {
266 up_read(&NILFS_SB(sb)->s_nilfs->ns_segctor_sem);
268 current->journal_info = ti->ti_save;
269 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
270 kmem_cache_free(nilfs_transaction_cachep, ti);
273 void nilfs_relax_pressure_in_lock(struct super_block *sb)
275 struct nilfs_sb_info *sbi = NILFS_SB(sb);
276 struct nilfs_sc_info *sci = NILFS_SC(sbi);
277 struct the_nilfs *nilfs = sbi->s_nilfs;
279 if (!sci || !sci->sc_flush_request)
282 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
283 up_read(&nilfs->ns_segctor_sem);
285 down_write(&nilfs->ns_segctor_sem);
286 if (sci->sc_flush_request &&
287 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
288 struct nilfs_transaction_info *ti = current->journal_info;
290 ti->ti_flags |= NILFS_TI_WRITER;
291 nilfs_segctor_do_immediate_flush(sci);
292 ti->ti_flags &= ~NILFS_TI_WRITER;
294 downgrade_write(&nilfs->ns_segctor_sem);
297 static void nilfs_transaction_lock(struct nilfs_sb_info *sbi,
298 struct nilfs_transaction_info *ti,
301 struct nilfs_transaction_info *cur_ti = current->journal_info;
304 ti->ti_flags = NILFS_TI_WRITER;
306 ti->ti_save = cur_ti;
307 ti->ti_magic = NILFS_TI_MAGIC;
308 INIT_LIST_HEAD(&ti->ti_garbage);
309 current->journal_info = ti;
312 down_write(&sbi->s_nilfs->ns_segctor_sem);
313 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &NILFS_SC(sbi)->sc_flags))
316 nilfs_segctor_do_immediate_flush(NILFS_SC(sbi));
318 up_write(&sbi->s_nilfs->ns_segctor_sem);
322 ti->ti_flags |= NILFS_TI_GC;
325 static void nilfs_transaction_unlock(struct nilfs_sb_info *sbi)
327 struct nilfs_transaction_info *ti = current->journal_info;
329 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
330 BUG_ON(ti->ti_count > 0);
332 up_write(&sbi->s_nilfs->ns_segctor_sem);
333 current->journal_info = ti->ti_save;
334 if (!list_empty(&ti->ti_garbage))
335 nilfs_dispose_list(sbi, &ti->ti_garbage, 0);
338 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
339 struct nilfs_segsum_pointer *ssp,
342 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
343 unsigned blocksize = sci->sc_super->s_blocksize;
346 if (unlikely(ssp->offset + bytes > blocksize)) {
348 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
349 &segbuf->sb_segsum_buffers));
350 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
352 p = ssp->bh->b_data + ssp->offset;
353 ssp->offset += bytes;
358 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
359 * @sci: nilfs_sc_info
361 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
363 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
364 struct buffer_head *sumbh;
369 if (nilfs_doing_gc())
371 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
375 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
376 sumbytes = segbuf->sb_sum.sumbytes;
377 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
378 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
379 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
383 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
385 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
386 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
387 return -E2BIG; /* The current segment is filled up
389 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
390 return nilfs_segctor_reset_segment_buffer(sci);
393 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
395 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
398 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
399 err = nilfs_segctor_feed_segment(sci);
402 segbuf = sci->sc_curseg;
404 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
406 segbuf->sb_sum.flags |= NILFS_SS_SR;
411 * Functions for making segment summary and payloads
413 static int nilfs_segctor_segsum_block_required(
414 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
417 unsigned blocksize = sci->sc_super->s_blocksize;
418 /* Size of finfo and binfo is enough small against blocksize */
420 return ssp->offset + binfo_size +
421 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
425 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
428 sci->sc_curseg->sb_sum.nfinfo++;
429 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
430 nilfs_segctor_map_segsum_entry(
431 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
433 if (NILFS_I(inode)->i_root &&
434 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
435 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
439 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
442 struct nilfs_finfo *finfo;
443 struct nilfs_inode_info *ii;
444 struct nilfs_segment_buffer *segbuf;
447 if (sci->sc_blk_cnt == 0)
452 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
454 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
459 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
461 finfo->fi_ino = cpu_to_le64(inode->i_ino);
462 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
463 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
464 finfo->fi_cno = cpu_to_le64(cno);
466 segbuf = sci->sc_curseg;
467 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
468 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
469 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
470 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
473 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
474 struct buffer_head *bh,
478 struct nilfs_segment_buffer *segbuf;
479 int required, err = 0;
482 segbuf = sci->sc_curseg;
483 required = nilfs_segctor_segsum_block_required(
484 sci, &sci->sc_binfo_ptr, binfo_size);
485 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
486 nilfs_segctor_end_finfo(sci, inode);
487 err = nilfs_segctor_feed_segment(sci);
492 if (unlikely(required)) {
493 err = nilfs_segbuf_extend_segsum(segbuf);
497 if (sci->sc_blk_cnt == 0)
498 nilfs_segctor_begin_finfo(sci, inode);
500 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
501 /* Substitution to vblocknr is delayed until update_blocknr() */
502 nilfs_segbuf_add_file_buffer(segbuf, bh);
509 * Callback functions that enumerate, mark, and collect dirty blocks
511 static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
512 struct buffer_head *bh, struct inode *inode)
516 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
520 err = nilfs_segctor_add_file_block(sci, bh, inode,
521 sizeof(struct nilfs_binfo_v));
523 sci->sc_datablk_cnt++;
527 static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
528 struct buffer_head *bh,
531 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
534 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
535 struct buffer_head *bh,
538 WARN_ON(!buffer_dirty(bh));
539 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
542 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
543 struct nilfs_segsum_pointer *ssp,
544 union nilfs_binfo *binfo)
546 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
547 sci, ssp, sizeof(*binfo_v));
548 *binfo_v = binfo->bi_v;
551 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
552 struct nilfs_segsum_pointer *ssp,
553 union nilfs_binfo *binfo)
555 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
556 sci, ssp, sizeof(*vblocknr));
557 *vblocknr = binfo->bi_v.bi_vblocknr;
560 static struct nilfs_sc_operations nilfs_sc_file_ops = {
561 .collect_data = nilfs_collect_file_data,
562 .collect_node = nilfs_collect_file_node,
563 .collect_bmap = nilfs_collect_file_bmap,
564 .write_data_binfo = nilfs_write_file_data_binfo,
565 .write_node_binfo = nilfs_write_file_node_binfo,
568 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
569 struct buffer_head *bh, struct inode *inode)
573 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
577 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
579 sci->sc_datablk_cnt++;
583 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
584 struct buffer_head *bh, struct inode *inode)
586 WARN_ON(!buffer_dirty(bh));
587 return nilfs_segctor_add_file_block(sci, bh, inode,
588 sizeof(struct nilfs_binfo_dat));
591 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
592 struct nilfs_segsum_pointer *ssp,
593 union nilfs_binfo *binfo)
595 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
597 *blkoff = binfo->bi_dat.bi_blkoff;
600 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
601 struct nilfs_segsum_pointer *ssp,
602 union nilfs_binfo *binfo)
604 struct nilfs_binfo_dat *binfo_dat =
605 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
606 *binfo_dat = binfo->bi_dat;
609 static struct nilfs_sc_operations nilfs_sc_dat_ops = {
610 .collect_data = nilfs_collect_dat_data,
611 .collect_node = nilfs_collect_file_node,
612 .collect_bmap = nilfs_collect_dat_bmap,
613 .write_data_binfo = nilfs_write_dat_data_binfo,
614 .write_node_binfo = nilfs_write_dat_node_binfo,
617 static struct nilfs_sc_operations nilfs_sc_dsync_ops = {
618 .collect_data = nilfs_collect_file_data,
619 .collect_node = NULL,
620 .collect_bmap = NULL,
621 .write_data_binfo = nilfs_write_file_data_binfo,
622 .write_node_binfo = NULL,
625 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
626 struct list_head *listp,
628 loff_t start, loff_t end)
630 struct address_space *mapping = inode->i_mapping;
632 pgoff_t index = 0, last = ULONG_MAX;
636 if (unlikely(start != 0 || end != LLONG_MAX)) {
638 * A valid range is given for sync-ing data pages. The
639 * range is rounded to per-page; extra dirty buffers
640 * may be included if blocksize < pagesize.
642 index = start >> PAGE_SHIFT;
643 last = end >> PAGE_SHIFT;
645 pagevec_init(&pvec, 0);
647 if (unlikely(index > last) ||
648 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
649 min_t(pgoff_t, last - index,
650 PAGEVEC_SIZE - 1) + 1))
653 for (i = 0; i < pagevec_count(&pvec); i++) {
654 struct buffer_head *bh, *head;
655 struct page *page = pvec.pages[i];
657 if (unlikely(page->index > last))
662 if (!page_has_buffers(page))
663 create_empty_buffers(page,
664 1 << inode->i_blkbits, 0);
668 bh = head = page_buffers(page);
670 if (!buffer_dirty(bh))
673 list_add_tail(&bh->b_assoc_buffers, listp);
675 if (unlikely(ndirties >= nlimit)) {
676 pagevec_release(&pvec);
680 } while (bh = bh->b_this_page, bh != head);
682 pagevec_release(&pvec);
687 static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
688 struct list_head *listp)
690 struct nilfs_inode_info *ii = NILFS_I(inode);
691 struct address_space *mapping = &ii->i_btnode_cache;
693 struct buffer_head *bh, *head;
697 pagevec_init(&pvec, 0);
699 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
701 for (i = 0; i < pagevec_count(&pvec); i++) {
702 bh = head = page_buffers(pvec.pages[i]);
704 if (buffer_dirty(bh)) {
706 list_add_tail(&bh->b_assoc_buffers,
709 bh = bh->b_this_page;
710 } while (bh != head);
712 pagevec_release(&pvec);
717 static void nilfs_dispose_list(struct nilfs_sb_info *sbi,
718 struct list_head *head, int force)
720 struct nilfs_inode_info *ii, *n;
721 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
724 while (!list_empty(head)) {
725 spin_lock(&sbi->s_inode_lock);
726 list_for_each_entry_safe(ii, n, head, i_dirty) {
727 list_del_init(&ii->i_dirty);
729 if (unlikely(ii->i_bh)) {
733 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
734 set_bit(NILFS_I_QUEUED, &ii->i_state);
735 list_add_tail(&ii->i_dirty,
736 &sbi->s_dirty_files);
740 if (nv == SC_N_INODEVEC)
743 spin_unlock(&sbi->s_inode_lock);
745 for (pii = ivec; nv > 0; pii++, nv--)
746 iput(&(*pii)->vfs_inode);
750 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
751 struct nilfs_root *root)
755 if (nilfs_mdt_fetch_dirty(root->ifile))
757 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
759 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
761 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
766 static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
768 return list_empty(&sci->sc_dirty_files) &&
769 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
770 sci->sc_nfreesegs == 0 &&
771 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
774 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
776 struct nilfs_sb_info *sbi = sci->sc_sbi;
779 if (nilfs_test_metadata_dirty(sbi->s_nilfs, sci->sc_root))
780 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
782 spin_lock(&sbi->s_inode_lock);
783 if (list_empty(&sbi->s_dirty_files) && nilfs_segctor_clean(sci))
786 spin_unlock(&sbi->s_inode_lock);
790 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
792 struct nilfs_sb_info *sbi = sci->sc_sbi;
793 struct the_nilfs *nilfs = sbi->s_nilfs;
795 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
796 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
797 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
798 nilfs_mdt_clear_dirty(nilfs->ns_dat);
801 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
803 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
804 struct buffer_head *bh_cp;
805 struct nilfs_checkpoint *raw_cp;
808 /* XXX: this interface will be changed */
809 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
812 /* The following code is duplicated with cpfile. But, it is
813 needed to collect the checkpoint even if it was not newly
815 nilfs_mdt_mark_buffer_dirty(bh_cp);
816 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
817 nilfs_cpfile_put_checkpoint(
818 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
820 WARN_ON(err == -EINVAL || err == -ENOENT);
825 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
827 struct nilfs_sb_info *sbi = sci->sc_sbi;
828 struct the_nilfs *nilfs = sbi->s_nilfs;
829 struct buffer_head *bh_cp;
830 struct nilfs_checkpoint *raw_cp;
833 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
836 WARN_ON(err == -EINVAL || err == -ENOENT);
839 raw_cp->cp_snapshot_list.ssl_next = 0;
840 raw_cp->cp_snapshot_list.ssl_prev = 0;
841 raw_cp->cp_inodes_count =
842 cpu_to_le64(atomic_read(&sci->sc_root->inodes_count));
843 raw_cp->cp_blocks_count =
844 cpu_to_le64(atomic_read(&sci->sc_root->blocks_count));
845 raw_cp->cp_nblk_inc =
846 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
847 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
848 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
850 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
851 nilfs_checkpoint_clear_minor(raw_cp);
853 nilfs_checkpoint_set_minor(raw_cp);
855 nilfs_write_inode_common(sci->sc_root->ifile,
856 &raw_cp->cp_ifile_inode, 1);
857 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
864 static void nilfs_fill_in_file_bmap(struct inode *ifile,
865 struct nilfs_inode_info *ii)
868 struct buffer_head *ibh;
869 struct nilfs_inode *raw_inode;
871 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
874 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
876 nilfs_bmap_write(ii->i_bmap, raw_inode);
877 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
881 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
883 struct nilfs_inode_info *ii;
885 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
886 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
887 set_bit(NILFS_I_COLLECTED, &ii->i_state);
891 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
892 struct the_nilfs *nilfs)
894 struct buffer_head *bh_sr;
895 struct nilfs_super_root *raw_sr;
896 unsigned isz = nilfs->ns_inode_size;
898 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
899 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
901 raw_sr->sr_bytes = cpu_to_le16(NILFS_SR_BYTES);
902 raw_sr->sr_nongc_ctime
903 = cpu_to_le64(nilfs_doing_gc() ?
904 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
905 raw_sr->sr_flags = 0;
907 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
908 NILFS_SR_DAT_OFFSET(isz), 1);
909 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
910 NILFS_SR_CPFILE_OFFSET(isz), 1);
911 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
912 NILFS_SR_SUFILE_OFFSET(isz), 1);
915 static void nilfs_redirty_inodes(struct list_head *head)
917 struct nilfs_inode_info *ii;
919 list_for_each_entry(ii, head, i_dirty) {
920 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
921 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
925 static void nilfs_drop_collected_inodes(struct list_head *head)
927 struct nilfs_inode_info *ii;
929 list_for_each_entry(ii, head, i_dirty) {
930 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
933 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
934 set_bit(NILFS_I_UPDATED, &ii->i_state);
938 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
940 struct list_head *listp,
941 int (*collect)(struct nilfs_sc_info *,
942 struct buffer_head *,
945 struct buffer_head *bh, *n;
949 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
950 list_del_init(&bh->b_assoc_buffers);
951 err = collect(sci, bh, inode);
954 goto dispose_buffers;
960 while (!list_empty(listp)) {
961 bh = list_entry(listp->next, struct buffer_head,
963 list_del_init(&bh->b_assoc_buffers);
969 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
971 /* Remaining number of blocks within segment buffer */
972 return sci->sc_segbuf_nblocks -
973 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
976 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
978 struct nilfs_sc_operations *sc_ops)
980 LIST_HEAD(data_buffers);
981 LIST_HEAD(node_buffers);
984 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
985 size_t n, rest = nilfs_segctor_buffer_rest(sci);
987 n = nilfs_lookup_dirty_data_buffers(
988 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
990 err = nilfs_segctor_apply_buffers(
991 sci, inode, &data_buffers,
992 sc_ops->collect_data);
993 BUG_ON(!err); /* always receive -E2BIG or true error */
997 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
999 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1000 err = nilfs_segctor_apply_buffers(
1001 sci, inode, &data_buffers, sc_ops->collect_data);
1002 if (unlikely(err)) {
1003 /* dispose node list */
1004 nilfs_segctor_apply_buffers(
1005 sci, inode, &node_buffers, NULL);
1008 sci->sc_stage.flags |= NILFS_CF_NODE;
1011 err = nilfs_segctor_apply_buffers(
1012 sci, inode, &node_buffers, sc_ops->collect_node);
1016 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1017 err = nilfs_segctor_apply_buffers(
1018 sci, inode, &node_buffers, sc_ops->collect_bmap);
1022 nilfs_segctor_end_finfo(sci, inode);
1023 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1029 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1030 struct inode *inode)
1032 LIST_HEAD(data_buffers);
1033 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1036 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1037 sci->sc_dsync_start,
1040 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1041 nilfs_collect_file_data);
1043 nilfs_segctor_end_finfo(sci, inode);
1045 /* always receive -E2BIG or true error if n > rest */
1050 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1052 struct nilfs_sb_info *sbi = sci->sc_sbi;
1053 struct the_nilfs *nilfs = sbi->s_nilfs;
1054 struct list_head *head;
1055 struct nilfs_inode_info *ii;
1059 switch (sci->sc_stage.scnt) {
1062 sci->sc_stage.flags = 0;
1064 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1065 sci->sc_nblk_inc = 0;
1066 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1067 if (mode == SC_LSEG_DSYNC) {
1068 sci->sc_stage.scnt = NILFS_ST_DSYNC;
1073 sci->sc_stage.dirty_file_ptr = NULL;
1074 sci->sc_stage.gc_inode_ptr = NULL;
1075 if (mode == SC_FLUSH_DAT) {
1076 sci->sc_stage.scnt = NILFS_ST_DAT;
1079 sci->sc_stage.scnt++; /* Fall through */
1081 if (nilfs_doing_gc()) {
1082 head = &sci->sc_gc_inodes;
1083 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1085 list_for_each_entry_continue(ii, head, i_dirty) {
1086 err = nilfs_segctor_scan_file(
1087 sci, &ii->vfs_inode,
1088 &nilfs_sc_file_ops);
1089 if (unlikely(err)) {
1090 sci->sc_stage.gc_inode_ptr = list_entry(
1092 struct nilfs_inode_info,
1096 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1098 sci->sc_stage.gc_inode_ptr = NULL;
1100 sci->sc_stage.scnt++; /* Fall through */
1102 head = &sci->sc_dirty_files;
1103 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1105 list_for_each_entry_continue(ii, head, i_dirty) {
1106 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1108 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1109 &nilfs_sc_file_ops);
1110 if (unlikely(err)) {
1111 sci->sc_stage.dirty_file_ptr =
1112 list_entry(ii->i_dirty.prev,
1113 struct nilfs_inode_info,
1117 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1118 /* XXX: required ? */
1120 sci->sc_stage.dirty_file_ptr = NULL;
1121 if (mode == SC_FLUSH_FILE) {
1122 sci->sc_stage.scnt = NILFS_ST_DONE;
1125 sci->sc_stage.scnt++;
1126 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1128 case NILFS_ST_IFILE:
1129 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1130 &nilfs_sc_file_ops);
1133 sci->sc_stage.scnt++;
1134 /* Creating a checkpoint */
1135 err = nilfs_segctor_create_checkpoint(sci);
1139 case NILFS_ST_CPFILE:
1140 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1141 &nilfs_sc_file_ops);
1144 sci->sc_stage.scnt++; /* Fall through */
1145 case NILFS_ST_SUFILE:
1146 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1147 sci->sc_nfreesegs, &ndone);
1148 if (unlikely(err)) {
1149 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1150 sci->sc_freesegs, ndone,
1154 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1156 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1157 &nilfs_sc_file_ops);
1160 sci->sc_stage.scnt++; /* Fall through */
1163 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1167 if (mode == SC_FLUSH_DAT) {
1168 sci->sc_stage.scnt = NILFS_ST_DONE;
1171 sci->sc_stage.scnt++; /* Fall through */
1173 if (mode == SC_LSEG_SR) {
1174 /* Appending a super root */
1175 err = nilfs_segctor_add_super_root(sci);
1179 /* End of a logical segment */
1180 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1181 sci->sc_stage.scnt = NILFS_ST_DONE;
1183 case NILFS_ST_DSYNC:
1185 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1186 ii = sci->sc_dsync_inode;
1187 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1190 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1193 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1194 sci->sc_stage.scnt = NILFS_ST_DONE;
1207 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1208 * @sci: nilfs_sc_info
1209 * @nilfs: nilfs object
1211 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1212 struct the_nilfs *nilfs)
1214 struct nilfs_segment_buffer *segbuf, *prev;
1218 segbuf = nilfs_segbuf_new(sci->sc_super);
1219 if (unlikely(!segbuf))
1222 if (list_empty(&sci->sc_write_logs)) {
1223 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1224 nilfs->ns_pseg_offset, nilfs);
1225 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1226 nilfs_shift_to_next_segment(nilfs);
1227 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1230 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1231 nextnum = nilfs->ns_nextnum;
1233 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1234 /* Start from the head of a new full segment */
1238 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1239 nilfs_segbuf_map_cont(segbuf, prev);
1240 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1241 nextnum = prev->sb_nextnum;
1243 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1244 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1245 segbuf->sb_sum.seg_seq++;
1250 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1255 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1259 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1261 BUG_ON(!list_empty(&sci->sc_segbufs));
1262 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1263 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1267 nilfs_segbuf_free(segbuf);
1271 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1272 struct the_nilfs *nilfs, int nadd)
1274 struct nilfs_segment_buffer *segbuf, *prev;
1275 struct inode *sufile = nilfs->ns_sufile;
1280 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1282 * Since the segment specified with nextnum might be allocated during
1283 * the previous construction, the buffer including its segusage may
1284 * not be dirty. The following call ensures that the buffer is dirty
1285 * and will pin the buffer on memory until the sufile is written.
1287 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1291 for (i = 0; i < nadd; i++) {
1292 /* extend segment info */
1294 segbuf = nilfs_segbuf_new(sci->sc_super);
1295 if (unlikely(!segbuf))
1298 /* map this buffer to region of segment on-disk */
1299 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1300 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1302 /* allocate the next next full segment */
1303 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1307 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1308 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1310 list_add_tail(&segbuf->sb_list, &list);
1313 list_splice_tail(&list, &sci->sc_segbufs);
1317 nilfs_segbuf_free(segbuf);
1319 list_for_each_entry(segbuf, &list, sb_list) {
1320 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1321 WARN_ON(ret); /* never fails */
1323 nilfs_destroy_logs(&list);
1327 static void nilfs_free_incomplete_logs(struct list_head *logs,
1328 struct the_nilfs *nilfs)
1330 struct nilfs_segment_buffer *segbuf, *prev;
1331 struct inode *sufile = nilfs->ns_sufile;
1334 segbuf = NILFS_FIRST_SEGBUF(logs);
1335 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1336 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1337 WARN_ON(ret); /* never fails */
1339 if (atomic_read(&segbuf->sb_err)) {
1340 /* Case 1: The first segment failed */
1341 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1342 /* Case 1a: Partial segment appended into an existing
1344 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1345 segbuf->sb_fseg_end);
1346 else /* Case 1b: New full segment */
1347 set_nilfs_discontinued(nilfs);
1351 list_for_each_entry_continue(segbuf, logs, sb_list) {
1352 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1353 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1354 WARN_ON(ret); /* never fails */
1356 if (atomic_read(&segbuf->sb_err) &&
1357 segbuf->sb_segnum != nilfs->ns_nextnum)
1358 /* Case 2: extended segment (!= next) failed */
1359 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1364 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1365 struct inode *sufile)
1367 struct nilfs_segment_buffer *segbuf;
1368 unsigned long live_blocks;
1371 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1372 live_blocks = segbuf->sb_sum.nblocks +
1373 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1374 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1377 WARN_ON(ret); /* always succeed because the segusage is dirty */
1381 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1383 struct nilfs_segment_buffer *segbuf;
1386 segbuf = NILFS_FIRST_SEGBUF(logs);
1387 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1388 segbuf->sb_pseg_start -
1389 segbuf->sb_fseg_start, 0);
1390 WARN_ON(ret); /* always succeed because the segusage is dirty */
1392 list_for_each_entry_continue(segbuf, logs, sb_list) {
1393 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1395 WARN_ON(ret); /* always succeed */
1399 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1400 struct nilfs_segment_buffer *last,
1401 struct inode *sufile)
1403 struct nilfs_segment_buffer *segbuf = last;
1406 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1407 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1408 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1411 nilfs_truncate_logs(&sci->sc_segbufs, last);
1415 static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1416 struct the_nilfs *nilfs, int mode)
1418 struct nilfs_cstage prev_stage = sci->sc_stage;
1421 /* Collection retry loop */
1423 sci->sc_nblk_this_inc = 0;
1424 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1426 err = nilfs_segctor_reset_segment_buffer(sci);
1430 err = nilfs_segctor_collect_blocks(sci, mode);
1431 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1435 if (unlikely(err != -E2BIG))
1438 /* The current segment is filled up */
1439 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE)
1442 nilfs_clear_logs(&sci->sc_segbufs);
1444 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1448 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1449 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1453 WARN_ON(err); /* do not happen */
1455 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1456 sci->sc_stage = prev_stage;
1458 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1465 static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1466 struct buffer_head *new_bh)
1468 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1470 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1471 /* The caller must release old_bh */
1475 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1476 struct nilfs_segment_buffer *segbuf,
1479 struct inode *inode = NULL;
1481 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1482 unsigned long nblocks = 0, ndatablk = 0;
1483 struct nilfs_sc_operations *sc_op = NULL;
1484 struct nilfs_segsum_pointer ssp;
1485 struct nilfs_finfo *finfo = NULL;
1486 union nilfs_binfo binfo;
1487 struct buffer_head *bh, *bh_org;
1494 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1495 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1496 ssp.offset = sizeof(struct nilfs_segment_summary);
1498 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1499 if (bh == segbuf->sb_super_root)
1502 finfo = nilfs_segctor_map_segsum_entry(
1503 sci, &ssp, sizeof(*finfo));
1504 ino = le64_to_cpu(finfo->fi_ino);
1505 nblocks = le32_to_cpu(finfo->fi_nblocks);
1506 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1508 if (buffer_nilfs_node(bh))
1509 inode = NILFS_BTNC_I(bh->b_page->mapping);
1511 inode = NILFS_AS_I(bh->b_page->mapping);
1513 if (mode == SC_LSEG_DSYNC)
1514 sc_op = &nilfs_sc_dsync_ops;
1515 else if (ino == NILFS_DAT_INO)
1516 sc_op = &nilfs_sc_dat_ops;
1517 else /* file blocks */
1518 sc_op = &nilfs_sc_file_ops;
1522 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1525 nilfs_list_replace_buffer(bh_org, bh);
1531 sc_op->write_data_binfo(sci, &ssp, &binfo);
1533 sc_op->write_node_binfo(sci, &ssp, &binfo);
1536 if (--nblocks == 0) {
1540 } else if (ndatablk > 0)
1550 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1552 struct nilfs_segment_buffer *segbuf;
1555 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1556 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1559 nilfs_segbuf_fill_in_segsum(segbuf);
1565 nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out)
1567 struct page *clone_page;
1568 struct buffer_head *bh, *head, *bh2;
1571 bh = head = page_buffers(page);
1573 clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0);
1574 if (unlikely(!clone_page))
1577 bh2 = page_buffers(clone_page);
1578 kaddr = kmap_atomic(page, KM_USER0);
1580 if (list_empty(&bh->b_assoc_buffers))
1583 page_cache_get(clone_page); /* for each bh */
1584 memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size);
1585 bh2->b_blocknr = bh->b_blocknr;
1586 list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers);
1587 list_add_tail(&bh->b_assoc_buffers, out);
1588 } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head);
1589 kunmap_atomic(kaddr, KM_USER0);
1591 if (!TestSetPageWriteback(clone_page))
1592 account_page_writeback(clone_page);
1593 unlock_page(clone_page);
1598 static int nilfs_test_page_to_be_frozen(struct page *page)
1600 struct address_space *mapping = page->mapping;
1602 if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode))
1605 if (page_mapped(page)) {
1606 ClearPageChecked(page);
1609 return PageChecked(page);
1612 static int nilfs_begin_page_io(struct page *page, struct list_head *out)
1614 if (!page || PageWriteback(page))
1615 /* For split b-tree node pages, this function may be called
1616 twice. We ignore the 2nd or later calls by this check. */
1620 clear_page_dirty_for_io(page);
1621 set_page_writeback(page);
1624 if (nilfs_test_page_to_be_frozen(page)) {
1625 int err = nilfs_copy_replace_page_buffers(page, out);
1632 static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci,
1633 struct page **failed_page)
1635 struct nilfs_segment_buffer *segbuf;
1636 struct page *bd_page = NULL, *fs_page = NULL;
1637 struct list_head *list = &sci->sc_copied_buffers;
1640 *failed_page = NULL;
1641 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1642 struct buffer_head *bh;
1644 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1646 if (bh->b_page != bd_page) {
1649 clear_page_dirty_for_io(bd_page);
1650 set_page_writeback(bd_page);
1651 unlock_page(bd_page);
1653 bd_page = bh->b_page;
1657 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1659 if (bh == segbuf->sb_super_root) {
1660 if (bh->b_page != bd_page) {
1662 clear_page_dirty_for_io(bd_page);
1663 set_page_writeback(bd_page);
1664 unlock_page(bd_page);
1665 bd_page = bh->b_page;
1669 if (bh->b_page != fs_page) {
1670 err = nilfs_begin_page_io(fs_page, list);
1671 if (unlikely(err)) {
1672 *failed_page = fs_page;
1675 fs_page = bh->b_page;
1681 clear_page_dirty_for_io(bd_page);
1682 set_page_writeback(bd_page);
1683 unlock_page(bd_page);
1685 err = nilfs_begin_page_io(fs_page, list);
1687 *failed_page = fs_page;
1692 static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1693 struct the_nilfs *nilfs)
1697 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1698 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1702 static void __nilfs_end_page_io(struct page *page, int err)
1705 if (!nilfs_page_buffers_clean(page))
1706 __set_page_dirty_nobuffers(page);
1707 ClearPageError(page);
1709 __set_page_dirty_nobuffers(page);
1713 if (buffer_nilfs_allocated(page_buffers(page))) {
1714 if (TestClearPageWriteback(page))
1715 dec_zone_page_state(page, NR_WRITEBACK);
1717 end_page_writeback(page);
1720 static void nilfs_end_page_io(struct page *page, int err)
1725 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1727 * For b-tree node pages, this function may be called twice
1728 * or more because they might be split in a segment.
1730 if (PageDirty(page)) {
1732 * For pages holding split b-tree node buffers, dirty
1733 * flag on the buffers may be cleared discretely.
1734 * In that case, the page is once redirtied for
1735 * remaining buffers, and it must be cancelled if
1736 * all the buffers get cleaned later.
1739 if (nilfs_page_buffers_clean(page))
1740 __nilfs_clear_page_dirty(page);
1746 __nilfs_end_page_io(page, err);
1749 static void nilfs_clear_copied_buffers(struct list_head *list, int err)
1751 struct buffer_head *bh, *head;
1754 while (!list_empty(list)) {
1755 bh = list_entry(list->next, struct buffer_head,
1758 page_cache_get(page);
1759 head = bh = page_buffers(page);
1761 if (!list_empty(&bh->b_assoc_buffers)) {
1762 list_del_init(&bh->b_assoc_buffers);
1764 set_buffer_uptodate(bh);
1765 clear_buffer_dirty(bh);
1766 clear_buffer_delay(bh);
1767 clear_buffer_nilfs_volatile(bh);
1769 brelse(bh); /* for b_assoc_buffers */
1771 } while ((bh = bh->b_this_page) != head);
1773 __nilfs_end_page_io(page, err);
1774 page_cache_release(page);
1778 static void nilfs_abort_logs(struct list_head *logs, struct page *failed_page,
1781 struct nilfs_segment_buffer *segbuf;
1782 struct page *bd_page = NULL, *fs_page = NULL;
1783 struct buffer_head *bh;
1785 if (list_empty(logs))
1788 list_for_each_entry(segbuf, logs, sb_list) {
1789 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1791 if (bh->b_page != bd_page) {
1793 end_page_writeback(bd_page);
1794 bd_page = bh->b_page;
1798 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1800 if (bh == segbuf->sb_super_root) {
1801 if (bh->b_page != bd_page) {
1802 end_page_writeback(bd_page);
1803 bd_page = bh->b_page;
1807 if (bh->b_page != fs_page) {
1808 nilfs_end_page_io(fs_page, err);
1809 if (fs_page && fs_page == failed_page)
1811 fs_page = bh->b_page;
1816 end_page_writeback(bd_page);
1818 nilfs_end_page_io(fs_page, err);
1821 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1822 struct the_nilfs *nilfs, int err)
1827 list_splice_tail_init(&sci->sc_write_logs, &logs);
1828 ret = nilfs_wait_on_logs(&logs);
1829 nilfs_abort_logs(&logs, NULL, ret ? : err);
1831 list_splice_tail_init(&sci->sc_segbufs, &logs);
1832 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1833 nilfs_free_incomplete_logs(&logs, nilfs);
1834 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err);
1836 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1837 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1841 WARN_ON(ret); /* do not happen */
1844 nilfs_destroy_logs(&logs);
1847 static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1848 struct nilfs_segment_buffer *segbuf)
1850 nilfs->ns_segnum = segbuf->sb_segnum;
1851 nilfs->ns_nextnum = segbuf->sb_nextnum;
1852 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1853 + segbuf->sb_sum.nblocks;
1854 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1855 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1858 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1860 struct nilfs_segment_buffer *segbuf;
1861 struct page *bd_page = NULL, *fs_page = NULL;
1862 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
1863 int update_sr = false;
1865 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1866 struct buffer_head *bh;
1868 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1870 set_buffer_uptodate(bh);
1871 clear_buffer_dirty(bh);
1872 if (bh->b_page != bd_page) {
1874 end_page_writeback(bd_page);
1875 bd_page = bh->b_page;
1879 * We assume that the buffers which belong to the same page
1880 * continue over the buffer list.
1881 * Under this assumption, the last BHs of pages is
1882 * identifiable by the discontinuity of bh->b_page
1883 * (page != fs_page).
1885 * For B-tree node blocks, however, this assumption is not
1886 * guaranteed. The cleanup code of B-tree node pages needs
1889 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1891 set_buffer_uptodate(bh);
1892 clear_buffer_dirty(bh);
1893 clear_buffer_delay(bh);
1894 clear_buffer_nilfs_volatile(bh);
1895 clear_buffer_nilfs_redirected(bh);
1896 if (bh == segbuf->sb_super_root) {
1897 if (bh->b_page != bd_page) {
1898 end_page_writeback(bd_page);
1899 bd_page = bh->b_page;
1904 if (bh->b_page != fs_page) {
1905 nilfs_end_page_io(fs_page, 0);
1906 fs_page = bh->b_page;
1910 if (!nilfs_segbuf_simplex(segbuf)) {
1911 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1912 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1913 sci->sc_lseg_stime = jiffies;
1915 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1916 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1920 * Since pages may continue over multiple segment buffers,
1921 * end of the last page must be checked outside of the loop.
1924 end_page_writeback(bd_page);
1926 nilfs_end_page_io(fs_page, 0);
1928 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0);
1930 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1932 if (nilfs_doing_gc())
1933 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1935 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1937 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1939 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1940 nilfs_set_next_segment(nilfs, segbuf);
1943 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1944 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1946 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1947 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1948 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1949 nilfs_segctor_clear_metadata_dirty(sci);
1951 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1954 static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1958 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1960 nilfs_segctor_complete_write(sci);
1961 nilfs_destroy_logs(&sci->sc_write_logs);
1966 static int nilfs_segctor_check_in_files(struct nilfs_sc_info *sci,
1967 struct nilfs_sb_info *sbi)
1969 struct nilfs_inode_info *ii, *n;
1970 struct inode *ifile = sci->sc_root->ifile;
1972 spin_lock(&sbi->s_inode_lock);
1974 list_for_each_entry_safe(ii, n, &sbi->s_dirty_files, i_dirty) {
1976 struct buffer_head *ibh;
1979 spin_unlock(&sbi->s_inode_lock);
1980 err = nilfs_ifile_get_inode_block(
1981 ifile, ii->vfs_inode.i_ino, &ibh);
1982 if (unlikely(err)) {
1983 nilfs_warning(sbi->s_super, __func__,
1984 "failed to get inode block.\n");
1987 nilfs_mdt_mark_buffer_dirty(ibh);
1988 nilfs_mdt_mark_dirty(ifile);
1989 spin_lock(&sbi->s_inode_lock);
1990 if (likely(!ii->i_bh))
1997 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1998 set_bit(NILFS_I_BUSY, &ii->i_state);
1999 list_del(&ii->i_dirty);
2000 list_add_tail(&ii->i_dirty, &sci->sc_dirty_files);
2002 spin_unlock(&sbi->s_inode_lock);
2007 static void nilfs_segctor_check_out_files(struct nilfs_sc_info *sci,
2008 struct nilfs_sb_info *sbi)
2010 struct nilfs_transaction_info *ti = current->journal_info;
2011 struct nilfs_inode_info *ii, *n;
2013 spin_lock(&sbi->s_inode_lock);
2014 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2015 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
2016 test_bit(NILFS_I_DIRTY, &ii->i_state))
2019 clear_bit(NILFS_I_BUSY, &ii->i_state);
2022 list_del(&ii->i_dirty);
2023 list_add_tail(&ii->i_dirty, &ti->ti_garbage);
2025 spin_unlock(&sbi->s_inode_lock);
2029 * Main procedure of segment constructor
2031 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2033 struct nilfs_sb_info *sbi = sci->sc_sbi;
2034 struct the_nilfs *nilfs = sbi->s_nilfs;
2035 struct page *failed_page;
2038 sci->sc_stage.scnt = NILFS_ST_INIT;
2039 sci->sc_cno = nilfs->ns_cno;
2041 err = nilfs_segctor_check_in_files(sci, sbi);
2045 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2046 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2048 if (nilfs_segctor_clean(sci))
2052 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2054 err = nilfs_segctor_begin_construction(sci, nilfs);
2058 /* Update time stamp */
2059 sci->sc_seg_ctime = get_seconds();
2061 err = nilfs_segctor_collect(sci, nilfs, mode);
2065 /* Avoid empty segment */
2066 if (sci->sc_stage.scnt == NILFS_ST_DONE &&
2067 nilfs_segbuf_empty(sci->sc_curseg)) {
2068 nilfs_segctor_abort_construction(sci, nilfs, 1);
2072 err = nilfs_segctor_assign(sci, mode);
2076 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2077 nilfs_segctor_fill_in_file_bmap(sci);
2079 if (mode == SC_LSEG_SR &&
2080 sci->sc_stage.scnt >= NILFS_ST_CPFILE) {
2081 err = nilfs_segctor_fill_in_checkpoint(sci);
2083 goto failed_to_write;
2085 nilfs_segctor_fill_in_super_root(sci, nilfs);
2087 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2089 /* Write partial segments */
2090 err = nilfs_segctor_prepare_write(sci, &failed_page);
2092 nilfs_abort_logs(&sci->sc_segbufs, failed_page, err);
2093 goto failed_to_write;
2096 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2097 nilfs->ns_crc_seed);
2099 err = nilfs_segctor_write(sci, nilfs);
2101 goto failed_to_write;
2103 if (sci->sc_stage.scnt == NILFS_ST_DONE ||
2104 nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) {
2106 * At this point, we avoid double buffering
2107 * for blocksize < pagesize because page dirty
2108 * flag is turned off during write and dirty
2109 * buffers are not properly collected for
2110 * pages crossing over segments.
2112 err = nilfs_segctor_wait(sci);
2114 goto failed_to_write;
2116 } while (sci->sc_stage.scnt != NILFS_ST_DONE);
2119 nilfs_segctor_check_out_files(sci, sbi);
2123 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2124 nilfs_redirty_inodes(&sci->sc_dirty_files);
2127 if (nilfs_doing_gc())
2128 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2129 nilfs_segctor_abort_construction(sci, nilfs, err);
2134 * nilfs_segctor_start_timer - set timer of background write
2135 * @sci: nilfs_sc_info
2137 * If the timer has already been set, it ignores the new request.
2138 * This function MUST be called within a section locking the segment
2141 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2143 spin_lock(&sci->sc_state_lock);
2144 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2145 sci->sc_timer.expires = jiffies + sci->sc_interval;
2146 add_timer(&sci->sc_timer);
2147 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2149 spin_unlock(&sci->sc_state_lock);
2152 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2154 spin_lock(&sci->sc_state_lock);
2155 if (!(sci->sc_flush_request & (1 << bn))) {
2156 unsigned long prev_req = sci->sc_flush_request;
2158 sci->sc_flush_request |= (1 << bn);
2160 wake_up(&sci->sc_wait_daemon);
2162 spin_unlock(&sci->sc_state_lock);
2166 * nilfs_flush_segment - trigger a segment construction for resource control
2168 * @ino: inode number of the file to be flushed out.
2170 void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2172 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2173 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2175 if (!sci || nilfs_doing_construction())
2177 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2178 /* assign bit 0 to data files */
2181 struct nilfs_segctor_wait_request {
2188 static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2190 struct nilfs_segctor_wait_request wait_req;
2193 spin_lock(&sci->sc_state_lock);
2194 init_wait(&wait_req.wq);
2196 atomic_set(&wait_req.done, 0);
2197 wait_req.seq = ++sci->sc_seq_request;
2198 spin_unlock(&sci->sc_state_lock);
2200 init_waitqueue_entry(&wait_req.wq, current);
2201 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2202 set_current_state(TASK_INTERRUPTIBLE);
2203 wake_up(&sci->sc_wait_daemon);
2206 if (atomic_read(&wait_req.done)) {
2210 if (!signal_pending(current)) {
2217 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2221 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2223 struct nilfs_segctor_wait_request *wrq, *n;
2224 unsigned long flags;
2226 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2227 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2229 if (!atomic_read(&wrq->done) &&
2230 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2232 atomic_set(&wrq->done, 1);
2234 if (atomic_read(&wrq->done)) {
2235 wrq->wq.func(&wrq->wq,
2236 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2240 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2244 * nilfs_construct_segment - construct a logical segment
2247 * Return Value: On success, 0 is retured. On errors, one of the following
2248 * negative error code is returned.
2250 * %-EROFS - Read only filesystem.
2254 * %-ENOSPC - No space left on device (only in a panic state).
2256 * %-ERESTARTSYS - Interrupted.
2258 * %-ENOMEM - Insufficient memory available.
2260 int nilfs_construct_segment(struct super_block *sb)
2262 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2263 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2264 struct nilfs_transaction_info *ti;
2270 /* A call inside transactions causes a deadlock. */
2271 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2273 err = nilfs_segctor_sync(sci);
2278 * nilfs_construct_dsync_segment - construct a data-only logical segment
2280 * @inode: inode whose data blocks should be written out
2281 * @start: start byte offset
2282 * @end: end byte offset (inclusive)
2284 * Return Value: On success, 0 is retured. On errors, one of the following
2285 * negative error code is returned.
2287 * %-EROFS - Read only filesystem.
2291 * %-ENOSPC - No space left on device (only in a panic state).
2293 * %-ERESTARTSYS - Interrupted.
2295 * %-ENOMEM - Insufficient memory available.
2297 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2298 loff_t start, loff_t end)
2300 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2301 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2302 struct nilfs_inode_info *ii;
2303 struct nilfs_transaction_info ti;
2309 nilfs_transaction_lock(sbi, &ti, 0);
2311 ii = NILFS_I(inode);
2312 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) ||
2313 nilfs_test_opt(sbi, STRICT_ORDER) ||
2314 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2315 nilfs_discontinued(sbi->s_nilfs)) {
2316 nilfs_transaction_unlock(sbi);
2317 err = nilfs_segctor_sync(sci);
2321 spin_lock(&sbi->s_inode_lock);
2322 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2323 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2324 spin_unlock(&sbi->s_inode_lock);
2325 nilfs_transaction_unlock(sbi);
2328 spin_unlock(&sbi->s_inode_lock);
2329 sci->sc_dsync_inode = ii;
2330 sci->sc_dsync_start = start;
2331 sci->sc_dsync_end = end;
2333 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2335 nilfs_transaction_unlock(sbi);
2339 #define FLUSH_FILE_BIT (0x1) /* data file only */
2340 #define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2343 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2344 * @sci: segment constructor object
2346 static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2348 spin_lock(&sci->sc_state_lock);
2349 sci->sc_seq_accepted = sci->sc_seq_request;
2350 spin_unlock(&sci->sc_state_lock);
2351 del_timer_sync(&sci->sc_timer);
2355 * nilfs_segctor_notify - notify the result of request to caller threads
2356 * @sci: segment constructor object
2357 * @mode: mode of log forming
2358 * @err: error code to be notified
2360 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2362 /* Clear requests (even when the construction failed) */
2363 spin_lock(&sci->sc_state_lock);
2365 if (mode == SC_LSEG_SR) {
2366 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2367 sci->sc_seq_done = sci->sc_seq_accepted;
2368 nilfs_segctor_wakeup(sci, err);
2369 sci->sc_flush_request = 0;
2371 if (mode == SC_FLUSH_FILE)
2372 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2373 else if (mode == SC_FLUSH_DAT)
2374 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2376 /* re-enable timer if checkpoint creation was not done */
2377 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2378 time_before(jiffies, sci->sc_timer.expires))
2379 add_timer(&sci->sc_timer);
2381 spin_unlock(&sci->sc_state_lock);
2385 * nilfs_segctor_construct - form logs and write them to disk
2386 * @sci: segment constructor object
2387 * @mode: mode of log forming
2389 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2391 struct nilfs_sb_info *sbi = sci->sc_sbi;
2392 struct the_nilfs *nilfs = sbi->s_nilfs;
2393 struct nilfs_super_block **sbp;
2396 nilfs_segctor_accept(sci);
2398 if (nilfs_discontinued(nilfs))
2400 if (!nilfs_segctor_confirm(sci))
2401 err = nilfs_segctor_do_construct(sci, mode);
2404 if (mode != SC_FLUSH_DAT)
2405 atomic_set(&nilfs->ns_ndirtyblks, 0);
2406 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2407 nilfs_discontinued(nilfs)) {
2408 down_write(&nilfs->ns_sem);
2410 sbp = nilfs_prepare_super(sbi,
2411 nilfs_sb_will_flip(nilfs));
2413 nilfs_set_log_cursor(sbp[0], nilfs);
2414 err = nilfs_commit_super(sbi, NILFS_SB_COMMIT);
2416 up_write(&nilfs->ns_sem);
2420 nilfs_segctor_notify(sci, mode, err);
2424 static void nilfs_construction_timeout(unsigned long data)
2426 struct task_struct *p = (struct task_struct *)data;
2431 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2433 struct nilfs_inode_info *ii, *n;
2435 list_for_each_entry_safe(ii, n, head, i_dirty) {
2436 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2438 list_del_init(&ii->i_dirty);
2439 iput(&ii->vfs_inode);
2443 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2446 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2447 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2448 struct the_nilfs *nilfs = sbi->s_nilfs;
2449 struct nilfs_transaction_info ti;
2455 nilfs_transaction_lock(sbi, &ti, 1);
2457 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2461 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2462 if (unlikely(err)) {
2463 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2467 sci->sc_freesegs = kbufs[4];
2468 sci->sc_nfreesegs = argv[4].v_nmembs;
2469 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2472 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2473 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2478 nilfs_warning(sb, __func__,
2479 "segment construction failed. (err=%d)", err);
2480 set_current_state(TASK_INTERRUPTIBLE);
2481 schedule_timeout(sci->sc_interval);
2483 if (nilfs_test_opt(sbi, DISCARD)) {
2484 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2488 "NILFS warning: error %d on discard request, "
2489 "turning discards off for the device\n", ret);
2490 nilfs_clear_opt(sbi, DISCARD);
2495 sci->sc_freesegs = NULL;
2496 sci->sc_nfreesegs = 0;
2497 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2498 nilfs_transaction_unlock(sbi);
2502 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2504 struct nilfs_sb_info *sbi = sci->sc_sbi;
2505 struct nilfs_transaction_info ti;
2507 nilfs_transaction_lock(sbi, &ti, 0);
2508 nilfs_segctor_construct(sci, mode);
2511 * Unclosed segment should be retried. We do this using sc_timer.
2512 * Timeout of sc_timer will invoke complete construction which leads
2513 * to close the current logical segment.
2515 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2516 nilfs_segctor_start_timer(sci);
2518 nilfs_transaction_unlock(sbi);
2521 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2526 spin_lock(&sci->sc_state_lock);
2527 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2528 SC_FLUSH_DAT : SC_FLUSH_FILE;
2529 spin_unlock(&sci->sc_state_lock);
2532 err = nilfs_segctor_do_construct(sci, mode);
2534 spin_lock(&sci->sc_state_lock);
2535 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2536 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2537 spin_unlock(&sci->sc_state_lock);
2539 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2542 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2544 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2545 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2546 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2547 return SC_FLUSH_FILE;
2548 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2549 return SC_FLUSH_DAT;
2555 * nilfs_segctor_thread - main loop of the segment constructor thread.
2556 * @arg: pointer to a struct nilfs_sc_info.
2558 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2559 * to execute segment constructions.
2561 static int nilfs_segctor_thread(void *arg)
2563 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2564 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
2567 sci->sc_timer.data = (unsigned long)current;
2568 sci->sc_timer.function = nilfs_construction_timeout;
2571 sci->sc_task = current;
2572 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2574 "segctord starting. Construction interval = %lu seconds, "
2575 "CP frequency < %lu seconds\n",
2576 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2578 spin_lock(&sci->sc_state_lock);
2583 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2586 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2588 else if (!sci->sc_flush_request)
2591 mode = nilfs_segctor_flush_mode(sci);
2593 spin_unlock(&sci->sc_state_lock);
2594 nilfs_segctor_thread_construct(sci, mode);
2595 spin_lock(&sci->sc_state_lock);
2600 if (freezing(current)) {
2601 spin_unlock(&sci->sc_state_lock);
2603 spin_lock(&sci->sc_state_lock);
2606 int should_sleep = 1;
2608 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2609 TASK_INTERRUPTIBLE);
2611 if (sci->sc_seq_request != sci->sc_seq_done)
2613 else if (sci->sc_flush_request)
2615 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2616 should_sleep = time_before(jiffies,
2617 sci->sc_timer.expires);
2620 spin_unlock(&sci->sc_state_lock);
2622 spin_lock(&sci->sc_state_lock);
2624 finish_wait(&sci->sc_wait_daemon, &wait);
2625 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2626 time_after_eq(jiffies, sci->sc_timer.expires));
2628 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2629 set_nilfs_discontinued(nilfs);
2634 spin_unlock(&sci->sc_state_lock);
2637 sci->sc_task = NULL;
2638 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2642 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2644 struct task_struct *t;
2646 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2648 int err = PTR_ERR(t);
2650 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2654 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2658 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2659 __acquires(&sci->sc_state_lock)
2660 __releases(&sci->sc_state_lock)
2662 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2664 while (sci->sc_task) {
2665 wake_up(&sci->sc_wait_daemon);
2666 spin_unlock(&sci->sc_state_lock);
2667 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2668 spin_lock(&sci->sc_state_lock);
2673 * Setup & clean-up functions
2675 static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi,
2676 struct nilfs_root *root)
2678 struct nilfs_sc_info *sci;
2680 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2685 sci->sc_super = sbi->s_super;
2687 nilfs_get_root(root);
2688 sci->sc_root = root;
2690 init_waitqueue_head(&sci->sc_wait_request);
2691 init_waitqueue_head(&sci->sc_wait_daemon);
2692 init_waitqueue_head(&sci->sc_wait_task);
2693 spin_lock_init(&sci->sc_state_lock);
2694 INIT_LIST_HEAD(&sci->sc_dirty_files);
2695 INIT_LIST_HEAD(&sci->sc_segbufs);
2696 INIT_LIST_HEAD(&sci->sc_write_logs);
2697 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2698 INIT_LIST_HEAD(&sci->sc_copied_buffers);
2699 init_timer(&sci->sc_timer);
2701 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2702 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2703 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2705 if (sbi->s_interval)
2706 sci->sc_interval = sbi->s_interval;
2707 if (sbi->s_watermark)
2708 sci->sc_watermark = sbi->s_watermark;
2712 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2714 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2716 /* The segctord thread was stopped and its timer was removed.
2717 But some tasks remain. */
2719 struct nilfs_sb_info *sbi = sci->sc_sbi;
2720 struct nilfs_transaction_info ti;
2722 nilfs_transaction_lock(sbi, &ti, 0);
2723 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2724 nilfs_transaction_unlock(sbi);
2726 } while (ret && retrycount-- > 0);
2730 * nilfs_segctor_destroy - destroy the segment constructor.
2731 * @sci: nilfs_sc_info
2733 * nilfs_segctor_destroy() kills the segctord thread and frees
2734 * the nilfs_sc_info struct.
2735 * Caller must hold the segment semaphore.
2737 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2739 struct nilfs_sb_info *sbi = sci->sc_sbi;
2742 up_write(&sbi->s_nilfs->ns_segctor_sem);
2744 spin_lock(&sci->sc_state_lock);
2745 nilfs_segctor_kill_thread(sci);
2746 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2747 || sci->sc_seq_request != sci->sc_seq_done);
2748 spin_unlock(&sci->sc_state_lock);
2750 if (flag || !nilfs_segctor_confirm(sci))
2751 nilfs_segctor_write_out(sci);
2753 WARN_ON(!list_empty(&sci->sc_copied_buffers));
2755 if (!list_empty(&sci->sc_dirty_files)) {
2756 nilfs_warning(sbi->s_super, __func__,
2757 "dirty file(s) after the final construction\n");
2758 nilfs_dispose_list(sbi, &sci->sc_dirty_files, 1);
2761 WARN_ON(!list_empty(&sci->sc_segbufs));
2762 WARN_ON(!list_empty(&sci->sc_write_logs));
2764 nilfs_put_root(sci->sc_root);
2766 down_write(&sbi->s_nilfs->ns_segctor_sem);
2768 del_timer_sync(&sci->sc_timer);
2773 * nilfs_attach_segment_constructor - attach a segment constructor
2774 * @sbi: nilfs_sb_info
2775 * @root: root object of the current filesystem tree
2777 * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info,
2778 * initializes it, and starts the segment constructor.
2780 * Return Value: On success, 0 is returned. On error, one of the following
2781 * negative error code is returned.
2783 * %-ENOMEM - Insufficient memory available.
2785 int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi,
2786 struct nilfs_root *root)
2790 if (NILFS_SC(sbi)) {
2792 * This happens if the filesystem was remounted
2793 * read/write after nilfs_error degenerated it into a
2796 nilfs_detach_segment_constructor(sbi);
2799 sbi->s_sc_info = nilfs_segctor_new(sbi, root);
2800 if (!sbi->s_sc_info)
2803 err = nilfs_segctor_start_thread(NILFS_SC(sbi));
2805 kfree(sbi->s_sc_info);
2806 sbi->s_sc_info = NULL;
2812 * nilfs_detach_segment_constructor - destroy the segment constructor
2813 * @sbi: nilfs_sb_info
2815 * nilfs_detach_segment_constructor() kills the segment constructor daemon,
2816 * frees the struct nilfs_sc_info, and destroy the dirty file list.
2818 void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi)
2820 struct the_nilfs *nilfs = sbi->s_nilfs;
2821 LIST_HEAD(garbage_list);
2823 down_write(&nilfs->ns_segctor_sem);
2824 if (NILFS_SC(sbi)) {
2825 nilfs_segctor_destroy(NILFS_SC(sbi));
2826 sbi->s_sc_info = NULL;
2829 /* Force to free the list of dirty files */
2830 spin_lock(&sbi->s_inode_lock);
2831 if (!list_empty(&sbi->s_dirty_files)) {
2832 list_splice_init(&sbi->s_dirty_files, &garbage_list);
2833 nilfs_warning(sbi->s_super, __func__,
2834 "Non empty dirty list after the last "
2835 "segment construction\n");
2837 spin_unlock(&sbi->s_inode_lock);
2838 up_write(&nilfs->ns_segctor_sem);
2840 nilfs_dispose_list(sbi, &garbage_list, 1);