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/bitops.h>
28 #include <linux/bio.h>
29 #include <linux/completion.h>
30 #include <linux/blkdev.h>
31 #include <linux/backing-dev.h>
32 #include <linux/freezer.h>
33 #include <linux/kthread.h>
34 #include <linux/crc32.h>
35 #include <linux/pagevec.h>
36 #include <linux/slab.h>
50 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
52 #define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments
53 appended in collection retry loop */
55 /* Construction mode */
57 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
58 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make
59 a logical segment without a super root */
60 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without
61 creating a checkpoint */
62 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without
66 /* Stage numbers of dirty block collection */
69 NILFS_ST_GC, /* Collecting dirty blocks for GC */
75 NILFS_ST_SR, /* Super root */
76 NILFS_ST_DSYNC, /* Data sync blocks */
80 #define CREATE_TRACE_POINTS
81 #include <trace/events/nilfs2.h>
84 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
85 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
86 * the variable must use them because transition of stage count must involve
87 * trace events (trace_nilfs2_collection_stage_transition).
89 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
90 * produce tracepoint events. It is provided just for making the intention
93 static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
96 trace_nilfs2_collection_stage_transition(sci);
99 static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
101 sci->sc_stage.scnt = next_scnt;
102 trace_nilfs2_collection_stage_transition(sci);
105 static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
107 return sci->sc_stage.scnt;
110 /* State flags of collection */
111 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
112 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
113 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
114 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
116 /* Operations depending on the construction mode and file type */
117 struct nilfs_sc_operations {
118 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
120 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
122 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
124 void (*write_data_binfo)(struct nilfs_sc_info *,
125 struct nilfs_segsum_pointer *,
126 union nilfs_binfo *);
127 void (*write_node_binfo)(struct nilfs_sc_info *,
128 struct nilfs_segsum_pointer *,
129 union nilfs_binfo *);
135 static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
136 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
137 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
138 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
140 #define nilfs_cnt32_gt(a, b) \
141 (typecheck(__u32, a) && typecheck(__u32, b) && \
142 ((__s32)(b) - (__s32)(a) < 0))
143 #define nilfs_cnt32_ge(a, b) \
144 (typecheck(__u32, a) && typecheck(__u32, b) && \
145 ((__s32)(a) - (__s32)(b) >= 0))
146 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
147 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
149 static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
151 struct nilfs_transaction_info *cur_ti = current->journal_info;
155 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
156 return ++cur_ti->ti_count;
159 * If journal_info field is occupied by other FS,
160 * it is saved and will be restored on
161 * nilfs_transaction_commit().
164 "NILFS warning: journal info from a different "
166 save = current->journal_info;
170 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
173 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
179 ti->ti_magic = NILFS_TI_MAGIC;
180 current->journal_info = ti;
185 * nilfs_transaction_begin - start indivisible file operations.
187 * @ti: nilfs_transaction_info
188 * @vacancy_check: flags for vacancy rate checks
190 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
191 * the segment semaphore, to make a segment construction and write tasks
192 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
193 * The region enclosed by these two functions can be nested. To avoid a
194 * deadlock, the semaphore is only acquired or released in the outermost call.
196 * This function allocates a nilfs_transaction_info struct to keep context
197 * information on it. It is initialized and hooked onto the current task in
198 * the outermost call. If a pre-allocated struct is given to @ti, it is used
199 * instead; otherwise a new struct is assigned from a slab.
201 * When @vacancy_check flag is set, this function will check the amount of
202 * free space, and will wait for the GC to reclaim disk space if low capacity.
204 * Return Value: On success, 0 is returned. On error, one of the following
205 * negative error code is returned.
207 * %-ENOMEM - Insufficient memory available.
209 * %-ENOSPC - No space left on device
211 int nilfs_transaction_begin(struct super_block *sb,
212 struct nilfs_transaction_info *ti,
215 struct the_nilfs *nilfs;
216 int ret = nilfs_prepare_segment_lock(ti);
217 struct nilfs_transaction_info *trace_ti;
219 if (unlikely(ret < 0))
222 trace_ti = current->journal_info;
224 trace_nilfs2_transaction_transition(sb, trace_ti,
225 trace_ti->ti_count, trace_ti->ti_flags,
226 TRACE_NILFS2_TRANSACTION_BEGIN);
230 sb_start_intwrite(sb);
232 nilfs = sb->s_fs_info;
233 down_read(&nilfs->ns_segctor_sem);
234 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
235 up_read(&nilfs->ns_segctor_sem);
240 trace_ti = current->journal_info;
241 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
243 TRACE_NILFS2_TRANSACTION_BEGIN);
247 ti = current->journal_info;
248 current->journal_info = ti->ti_save;
249 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
250 kmem_cache_free(nilfs_transaction_cachep, ti);
256 * nilfs_transaction_commit - commit indivisible file operations.
259 * nilfs_transaction_commit() releases the read semaphore which is
260 * acquired by nilfs_transaction_begin(). This is only performed
261 * in outermost call of this function. If a commit flag is set,
262 * nilfs_transaction_commit() sets a timer to start the segment
263 * constructor. If a sync flag is set, it starts construction
266 int nilfs_transaction_commit(struct super_block *sb)
268 struct nilfs_transaction_info *ti = current->journal_info;
269 struct the_nilfs *nilfs = sb->s_fs_info;
272 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
273 ti->ti_flags |= NILFS_TI_COMMIT;
274 if (ti->ti_count > 0) {
276 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
277 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
280 if (nilfs->ns_writer) {
281 struct nilfs_sc_info *sci = nilfs->ns_writer;
283 if (ti->ti_flags & NILFS_TI_COMMIT)
284 nilfs_segctor_start_timer(sci);
285 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
286 nilfs_segctor_do_flush(sci, 0);
288 up_read(&nilfs->ns_segctor_sem);
289 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
290 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
292 current->journal_info = ti->ti_save;
294 if (ti->ti_flags & NILFS_TI_SYNC)
295 err = nilfs_construct_segment(sb);
296 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
297 kmem_cache_free(nilfs_transaction_cachep, ti);
302 void nilfs_transaction_abort(struct super_block *sb)
304 struct nilfs_transaction_info *ti = current->journal_info;
305 struct the_nilfs *nilfs = sb->s_fs_info;
307 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
308 if (ti->ti_count > 0) {
310 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
311 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
314 up_read(&nilfs->ns_segctor_sem);
316 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
317 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
319 current->journal_info = ti->ti_save;
320 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
321 kmem_cache_free(nilfs_transaction_cachep, ti);
325 void nilfs_relax_pressure_in_lock(struct super_block *sb)
327 struct the_nilfs *nilfs = sb->s_fs_info;
328 struct nilfs_sc_info *sci = nilfs->ns_writer;
330 if (!sci || !sci->sc_flush_request)
333 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
334 up_read(&nilfs->ns_segctor_sem);
336 down_write(&nilfs->ns_segctor_sem);
337 if (sci->sc_flush_request &&
338 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
339 struct nilfs_transaction_info *ti = current->journal_info;
341 ti->ti_flags |= NILFS_TI_WRITER;
342 nilfs_segctor_do_immediate_flush(sci);
343 ti->ti_flags &= ~NILFS_TI_WRITER;
345 downgrade_write(&nilfs->ns_segctor_sem);
348 static void nilfs_transaction_lock(struct super_block *sb,
349 struct nilfs_transaction_info *ti,
352 struct nilfs_transaction_info *cur_ti = current->journal_info;
353 struct the_nilfs *nilfs = sb->s_fs_info;
354 struct nilfs_sc_info *sci = nilfs->ns_writer;
357 ti->ti_flags = NILFS_TI_WRITER;
359 ti->ti_save = cur_ti;
360 ti->ti_magic = NILFS_TI_MAGIC;
361 current->journal_info = ti;
364 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
365 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
367 down_write(&nilfs->ns_segctor_sem);
368 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
371 nilfs_segctor_do_immediate_flush(sci);
373 up_write(&nilfs->ns_segctor_sem);
377 ti->ti_flags |= NILFS_TI_GC;
379 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
380 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
383 static void nilfs_transaction_unlock(struct super_block *sb)
385 struct nilfs_transaction_info *ti = current->journal_info;
386 struct the_nilfs *nilfs = sb->s_fs_info;
388 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
389 BUG_ON(ti->ti_count > 0);
391 up_write(&nilfs->ns_segctor_sem);
392 current->journal_info = ti->ti_save;
394 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
395 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
398 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
399 struct nilfs_segsum_pointer *ssp,
402 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
403 unsigned blocksize = sci->sc_super->s_blocksize;
406 if (unlikely(ssp->offset + bytes > blocksize)) {
408 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
409 &segbuf->sb_segsum_buffers));
410 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
412 p = ssp->bh->b_data + ssp->offset;
413 ssp->offset += bytes;
418 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
419 * @sci: nilfs_sc_info
421 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
423 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
424 struct buffer_head *sumbh;
429 if (nilfs_doing_gc())
431 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
435 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
436 sumbytes = segbuf->sb_sum.sumbytes;
437 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
438 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
439 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
443 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
445 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
446 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
447 return -E2BIG; /* The current segment is filled up
449 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
450 return nilfs_segctor_reset_segment_buffer(sci);
453 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
455 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
458 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
459 err = nilfs_segctor_feed_segment(sci);
462 segbuf = sci->sc_curseg;
464 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
466 segbuf->sb_sum.flags |= NILFS_SS_SR;
471 * Functions for making segment summary and payloads
473 static int nilfs_segctor_segsum_block_required(
474 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
477 unsigned blocksize = sci->sc_super->s_blocksize;
478 /* Size of finfo and binfo is enough small against blocksize */
480 return ssp->offset + binfo_size +
481 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
485 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
488 sci->sc_curseg->sb_sum.nfinfo++;
489 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
490 nilfs_segctor_map_segsum_entry(
491 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
493 if (NILFS_I(inode)->i_root &&
494 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
495 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
499 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
502 struct nilfs_finfo *finfo;
503 struct nilfs_inode_info *ii;
504 struct nilfs_segment_buffer *segbuf;
507 if (sci->sc_blk_cnt == 0)
512 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
514 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
519 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
521 finfo->fi_ino = cpu_to_le64(inode->i_ino);
522 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
523 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
524 finfo->fi_cno = cpu_to_le64(cno);
526 segbuf = sci->sc_curseg;
527 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
528 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
529 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
530 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
533 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
534 struct buffer_head *bh,
538 struct nilfs_segment_buffer *segbuf;
539 int required, err = 0;
542 segbuf = sci->sc_curseg;
543 required = nilfs_segctor_segsum_block_required(
544 sci, &sci->sc_binfo_ptr, binfo_size);
545 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
546 nilfs_segctor_end_finfo(sci, inode);
547 err = nilfs_segctor_feed_segment(sci);
552 if (unlikely(required)) {
553 err = nilfs_segbuf_extend_segsum(segbuf);
557 if (sci->sc_blk_cnt == 0)
558 nilfs_segctor_begin_finfo(sci, inode);
560 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
561 /* Substitution to vblocknr is delayed until update_blocknr() */
562 nilfs_segbuf_add_file_buffer(segbuf, bh);
569 * Callback functions that enumerate, mark, and collect dirty blocks
571 static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
572 struct buffer_head *bh, struct inode *inode)
576 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
580 err = nilfs_segctor_add_file_block(sci, bh, inode,
581 sizeof(struct nilfs_binfo_v));
583 sci->sc_datablk_cnt++;
587 static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
588 struct buffer_head *bh,
591 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
594 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
595 struct buffer_head *bh,
598 WARN_ON(!buffer_dirty(bh));
599 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
602 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
603 struct nilfs_segsum_pointer *ssp,
604 union nilfs_binfo *binfo)
606 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
607 sci, ssp, sizeof(*binfo_v));
608 *binfo_v = binfo->bi_v;
611 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
612 struct nilfs_segsum_pointer *ssp,
613 union nilfs_binfo *binfo)
615 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
616 sci, ssp, sizeof(*vblocknr));
617 *vblocknr = binfo->bi_v.bi_vblocknr;
620 static struct nilfs_sc_operations nilfs_sc_file_ops = {
621 .collect_data = nilfs_collect_file_data,
622 .collect_node = nilfs_collect_file_node,
623 .collect_bmap = nilfs_collect_file_bmap,
624 .write_data_binfo = nilfs_write_file_data_binfo,
625 .write_node_binfo = nilfs_write_file_node_binfo,
628 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
629 struct buffer_head *bh, struct inode *inode)
633 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
637 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
639 sci->sc_datablk_cnt++;
643 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
644 struct buffer_head *bh, struct inode *inode)
646 WARN_ON(!buffer_dirty(bh));
647 return nilfs_segctor_add_file_block(sci, bh, inode,
648 sizeof(struct nilfs_binfo_dat));
651 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
652 struct nilfs_segsum_pointer *ssp,
653 union nilfs_binfo *binfo)
655 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
657 *blkoff = binfo->bi_dat.bi_blkoff;
660 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
661 struct nilfs_segsum_pointer *ssp,
662 union nilfs_binfo *binfo)
664 struct nilfs_binfo_dat *binfo_dat =
665 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
666 *binfo_dat = binfo->bi_dat;
669 static struct nilfs_sc_operations nilfs_sc_dat_ops = {
670 .collect_data = nilfs_collect_dat_data,
671 .collect_node = nilfs_collect_file_node,
672 .collect_bmap = nilfs_collect_dat_bmap,
673 .write_data_binfo = nilfs_write_dat_data_binfo,
674 .write_node_binfo = nilfs_write_dat_node_binfo,
677 static struct nilfs_sc_operations nilfs_sc_dsync_ops = {
678 .collect_data = nilfs_collect_file_data,
679 .collect_node = NULL,
680 .collect_bmap = NULL,
681 .write_data_binfo = nilfs_write_file_data_binfo,
682 .write_node_binfo = NULL,
685 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
686 struct list_head *listp,
688 loff_t start, loff_t end)
690 struct address_space *mapping = inode->i_mapping;
692 pgoff_t index = 0, last = ULONG_MAX;
696 if (unlikely(start != 0 || end != LLONG_MAX)) {
698 * A valid range is given for sync-ing data pages. The
699 * range is rounded to per-page; extra dirty buffers
700 * may be included if blocksize < pagesize.
702 index = start >> PAGE_SHIFT;
703 last = end >> PAGE_SHIFT;
705 pagevec_init(&pvec, 0);
707 if (unlikely(index > last) ||
708 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
709 min_t(pgoff_t, last - index,
710 PAGEVEC_SIZE - 1) + 1))
713 for (i = 0; i < pagevec_count(&pvec); i++) {
714 struct buffer_head *bh, *head;
715 struct page *page = pvec.pages[i];
717 if (unlikely(page->index > last))
721 if (!page_has_buffers(page))
722 create_empty_buffers(page, 1 << inode->i_blkbits, 0);
725 bh = head = page_buffers(page);
727 if (!buffer_dirty(bh) || buffer_async_write(bh))
730 list_add_tail(&bh->b_assoc_buffers, listp);
732 if (unlikely(ndirties >= nlimit)) {
733 pagevec_release(&pvec);
737 } while (bh = bh->b_this_page, bh != head);
739 pagevec_release(&pvec);
744 static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
745 struct list_head *listp)
747 struct nilfs_inode_info *ii = NILFS_I(inode);
748 struct address_space *mapping = &ii->i_btnode_cache;
750 struct buffer_head *bh, *head;
754 pagevec_init(&pvec, 0);
756 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
758 for (i = 0; i < pagevec_count(&pvec); i++) {
759 bh = head = page_buffers(pvec.pages[i]);
761 if (buffer_dirty(bh) &&
762 !buffer_async_write(bh)) {
764 list_add_tail(&bh->b_assoc_buffers,
767 bh = bh->b_this_page;
768 } while (bh != head);
770 pagevec_release(&pvec);
775 static void nilfs_dispose_list(struct the_nilfs *nilfs,
776 struct list_head *head, int force)
778 struct nilfs_inode_info *ii, *n;
779 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
782 while (!list_empty(head)) {
783 spin_lock(&nilfs->ns_inode_lock);
784 list_for_each_entry_safe(ii, n, head, i_dirty) {
785 list_del_init(&ii->i_dirty);
787 if (unlikely(ii->i_bh)) {
791 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
792 set_bit(NILFS_I_QUEUED, &ii->i_state);
793 list_add_tail(&ii->i_dirty,
794 &nilfs->ns_dirty_files);
798 if (nv == SC_N_INODEVEC)
801 spin_unlock(&nilfs->ns_inode_lock);
803 for (pii = ivec; nv > 0; pii++, nv--)
804 iput(&(*pii)->vfs_inode);
808 static void nilfs_iput_work_func(struct work_struct *work)
810 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
812 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
814 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
817 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
818 struct nilfs_root *root)
822 if (nilfs_mdt_fetch_dirty(root->ifile))
824 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
826 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
828 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
833 static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
835 return list_empty(&sci->sc_dirty_files) &&
836 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
837 sci->sc_nfreesegs == 0 &&
838 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
841 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
843 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
846 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
847 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
849 spin_lock(&nilfs->ns_inode_lock);
850 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
853 spin_unlock(&nilfs->ns_inode_lock);
857 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
859 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
861 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
862 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
863 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
864 nilfs_mdt_clear_dirty(nilfs->ns_dat);
867 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
869 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
870 struct buffer_head *bh_cp;
871 struct nilfs_checkpoint *raw_cp;
874 /* XXX: this interface will be changed */
875 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
878 /* The following code is duplicated with cpfile. But, it is
879 needed to collect the checkpoint even if it was not newly
881 mark_buffer_dirty(bh_cp);
882 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
883 nilfs_cpfile_put_checkpoint(
884 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
886 WARN_ON(err == -EINVAL || err == -ENOENT);
891 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
893 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
894 struct buffer_head *bh_cp;
895 struct nilfs_checkpoint *raw_cp;
898 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
901 WARN_ON(err == -EINVAL || err == -ENOENT);
904 raw_cp->cp_snapshot_list.ssl_next = 0;
905 raw_cp->cp_snapshot_list.ssl_prev = 0;
906 raw_cp->cp_inodes_count =
907 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
908 raw_cp->cp_blocks_count =
909 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
910 raw_cp->cp_nblk_inc =
911 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
912 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
913 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
915 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
916 nilfs_checkpoint_clear_minor(raw_cp);
918 nilfs_checkpoint_set_minor(raw_cp);
920 nilfs_write_inode_common(sci->sc_root->ifile,
921 &raw_cp->cp_ifile_inode, 1);
922 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
929 static void nilfs_fill_in_file_bmap(struct inode *ifile,
930 struct nilfs_inode_info *ii)
933 struct buffer_head *ibh;
934 struct nilfs_inode *raw_inode;
936 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
939 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
941 nilfs_bmap_write(ii->i_bmap, raw_inode);
942 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
946 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
948 struct nilfs_inode_info *ii;
950 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
951 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
952 set_bit(NILFS_I_COLLECTED, &ii->i_state);
956 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
957 struct the_nilfs *nilfs)
959 struct buffer_head *bh_sr;
960 struct nilfs_super_root *raw_sr;
963 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
964 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
965 isz = nilfs->ns_inode_size;
966 srsz = NILFS_SR_BYTES(isz);
968 raw_sr->sr_bytes = cpu_to_le16(srsz);
969 raw_sr->sr_nongc_ctime
970 = cpu_to_le64(nilfs_doing_gc() ?
971 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
972 raw_sr->sr_flags = 0;
974 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
975 NILFS_SR_DAT_OFFSET(isz), 1);
976 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
977 NILFS_SR_CPFILE_OFFSET(isz), 1);
978 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
979 NILFS_SR_SUFILE_OFFSET(isz), 1);
980 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
983 static void nilfs_redirty_inodes(struct list_head *head)
985 struct nilfs_inode_info *ii;
987 list_for_each_entry(ii, head, i_dirty) {
988 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
989 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
993 static void nilfs_drop_collected_inodes(struct list_head *head)
995 struct nilfs_inode_info *ii;
997 list_for_each_entry(ii, head, i_dirty) {
998 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
1001 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
1002 set_bit(NILFS_I_UPDATED, &ii->i_state);
1006 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1007 struct inode *inode,
1008 struct list_head *listp,
1009 int (*collect)(struct nilfs_sc_info *,
1010 struct buffer_head *,
1013 struct buffer_head *bh, *n;
1017 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1018 list_del_init(&bh->b_assoc_buffers);
1019 err = collect(sci, bh, inode);
1022 goto dispose_buffers;
1028 while (!list_empty(listp)) {
1029 bh = list_first_entry(listp, struct buffer_head,
1031 list_del_init(&bh->b_assoc_buffers);
1037 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1039 /* Remaining number of blocks within segment buffer */
1040 return sci->sc_segbuf_nblocks -
1041 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1044 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1045 struct inode *inode,
1046 struct nilfs_sc_operations *sc_ops)
1048 LIST_HEAD(data_buffers);
1049 LIST_HEAD(node_buffers);
1052 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1053 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1055 n = nilfs_lookup_dirty_data_buffers(
1056 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1058 err = nilfs_segctor_apply_buffers(
1059 sci, inode, &data_buffers,
1060 sc_ops->collect_data);
1061 BUG_ON(!err); /* always receive -E2BIG or true error */
1065 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1067 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1068 err = nilfs_segctor_apply_buffers(
1069 sci, inode, &data_buffers, sc_ops->collect_data);
1070 if (unlikely(err)) {
1071 /* dispose node list */
1072 nilfs_segctor_apply_buffers(
1073 sci, inode, &node_buffers, NULL);
1076 sci->sc_stage.flags |= NILFS_CF_NODE;
1079 err = nilfs_segctor_apply_buffers(
1080 sci, inode, &node_buffers, sc_ops->collect_node);
1084 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1085 err = nilfs_segctor_apply_buffers(
1086 sci, inode, &node_buffers, sc_ops->collect_bmap);
1090 nilfs_segctor_end_finfo(sci, inode);
1091 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1097 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1098 struct inode *inode)
1100 LIST_HEAD(data_buffers);
1101 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1104 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1105 sci->sc_dsync_start,
1108 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1109 nilfs_collect_file_data);
1111 nilfs_segctor_end_finfo(sci, inode);
1113 /* always receive -E2BIG or true error if n > rest */
1118 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1120 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1121 struct list_head *head;
1122 struct nilfs_inode_info *ii;
1126 switch (nilfs_sc_cstage_get(sci)) {
1129 sci->sc_stage.flags = 0;
1131 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1132 sci->sc_nblk_inc = 0;
1133 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1134 if (mode == SC_LSEG_DSYNC) {
1135 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1140 sci->sc_stage.dirty_file_ptr = NULL;
1141 sci->sc_stage.gc_inode_ptr = NULL;
1142 if (mode == SC_FLUSH_DAT) {
1143 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1146 nilfs_sc_cstage_inc(sci); /* Fall through */
1148 if (nilfs_doing_gc()) {
1149 head = &sci->sc_gc_inodes;
1150 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1152 list_for_each_entry_continue(ii, head, i_dirty) {
1153 err = nilfs_segctor_scan_file(
1154 sci, &ii->vfs_inode,
1155 &nilfs_sc_file_ops);
1156 if (unlikely(err)) {
1157 sci->sc_stage.gc_inode_ptr = list_entry(
1159 struct nilfs_inode_info,
1163 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1165 sci->sc_stage.gc_inode_ptr = NULL;
1167 nilfs_sc_cstage_inc(sci); /* Fall through */
1169 head = &sci->sc_dirty_files;
1170 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1172 list_for_each_entry_continue(ii, head, i_dirty) {
1173 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1175 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1176 &nilfs_sc_file_ops);
1177 if (unlikely(err)) {
1178 sci->sc_stage.dirty_file_ptr =
1179 list_entry(ii->i_dirty.prev,
1180 struct nilfs_inode_info,
1184 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1185 /* XXX: required ? */
1187 sci->sc_stage.dirty_file_ptr = NULL;
1188 if (mode == SC_FLUSH_FILE) {
1189 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1192 nilfs_sc_cstage_inc(sci);
1193 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1195 case NILFS_ST_IFILE:
1196 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1197 &nilfs_sc_file_ops);
1200 nilfs_sc_cstage_inc(sci);
1201 /* Creating a checkpoint */
1202 err = nilfs_segctor_create_checkpoint(sci);
1206 case NILFS_ST_CPFILE:
1207 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1208 &nilfs_sc_file_ops);
1211 nilfs_sc_cstage_inc(sci); /* Fall through */
1212 case NILFS_ST_SUFILE:
1213 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1214 sci->sc_nfreesegs, &ndone);
1215 if (unlikely(err)) {
1216 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1217 sci->sc_freesegs, ndone,
1221 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1223 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1224 &nilfs_sc_file_ops);
1227 nilfs_sc_cstage_inc(sci); /* Fall through */
1230 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1234 if (mode == SC_FLUSH_DAT) {
1235 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1238 nilfs_sc_cstage_inc(sci); /* Fall through */
1240 if (mode == SC_LSEG_SR) {
1241 /* Appending a super root */
1242 err = nilfs_segctor_add_super_root(sci);
1246 /* End of a logical segment */
1247 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1248 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1250 case NILFS_ST_DSYNC:
1252 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1253 ii = sci->sc_dsync_inode;
1254 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1257 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1260 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1261 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1274 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1275 * @sci: nilfs_sc_info
1276 * @nilfs: nilfs object
1278 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1279 struct the_nilfs *nilfs)
1281 struct nilfs_segment_buffer *segbuf, *prev;
1285 segbuf = nilfs_segbuf_new(sci->sc_super);
1286 if (unlikely(!segbuf))
1289 if (list_empty(&sci->sc_write_logs)) {
1290 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1291 nilfs->ns_pseg_offset, nilfs);
1292 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1293 nilfs_shift_to_next_segment(nilfs);
1294 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1297 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1298 nextnum = nilfs->ns_nextnum;
1300 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1301 /* Start from the head of a new full segment */
1305 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1306 nilfs_segbuf_map_cont(segbuf, prev);
1307 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1308 nextnum = prev->sb_nextnum;
1310 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1311 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1312 segbuf->sb_sum.seg_seq++;
1317 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1322 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1326 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1328 BUG_ON(!list_empty(&sci->sc_segbufs));
1329 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1330 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1334 nilfs_segbuf_free(segbuf);
1338 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1339 struct the_nilfs *nilfs, int nadd)
1341 struct nilfs_segment_buffer *segbuf, *prev;
1342 struct inode *sufile = nilfs->ns_sufile;
1347 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1349 * Since the segment specified with nextnum might be allocated during
1350 * the previous construction, the buffer including its segusage may
1351 * not be dirty. The following call ensures that the buffer is dirty
1352 * and will pin the buffer on memory until the sufile is written.
1354 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1358 for (i = 0; i < nadd; i++) {
1359 /* extend segment info */
1361 segbuf = nilfs_segbuf_new(sci->sc_super);
1362 if (unlikely(!segbuf))
1365 /* map this buffer to region of segment on-disk */
1366 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1367 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1369 /* allocate the next next full segment */
1370 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1374 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1375 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1377 list_add_tail(&segbuf->sb_list, &list);
1380 list_splice_tail(&list, &sci->sc_segbufs);
1384 nilfs_segbuf_free(segbuf);
1386 list_for_each_entry(segbuf, &list, sb_list) {
1387 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1388 WARN_ON(ret); /* never fails */
1390 nilfs_destroy_logs(&list);
1394 static void nilfs_free_incomplete_logs(struct list_head *logs,
1395 struct the_nilfs *nilfs)
1397 struct nilfs_segment_buffer *segbuf, *prev;
1398 struct inode *sufile = nilfs->ns_sufile;
1401 segbuf = NILFS_FIRST_SEGBUF(logs);
1402 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1403 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1404 WARN_ON(ret); /* never fails */
1406 if (atomic_read(&segbuf->sb_err)) {
1407 /* Case 1: The first segment failed */
1408 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1409 /* Case 1a: Partial segment appended into an existing
1411 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1412 segbuf->sb_fseg_end);
1413 else /* Case 1b: New full segment */
1414 set_nilfs_discontinued(nilfs);
1418 list_for_each_entry_continue(segbuf, logs, sb_list) {
1419 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1420 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1421 WARN_ON(ret); /* never fails */
1423 if (atomic_read(&segbuf->sb_err) &&
1424 segbuf->sb_segnum != nilfs->ns_nextnum)
1425 /* Case 2: extended segment (!= next) failed */
1426 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1431 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1432 struct inode *sufile)
1434 struct nilfs_segment_buffer *segbuf;
1435 unsigned long live_blocks;
1438 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1439 live_blocks = segbuf->sb_sum.nblocks +
1440 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1441 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1444 WARN_ON(ret); /* always succeed because the segusage is dirty */
1448 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1450 struct nilfs_segment_buffer *segbuf;
1453 segbuf = NILFS_FIRST_SEGBUF(logs);
1454 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1455 segbuf->sb_pseg_start -
1456 segbuf->sb_fseg_start, 0);
1457 WARN_ON(ret); /* always succeed because the segusage is dirty */
1459 list_for_each_entry_continue(segbuf, logs, sb_list) {
1460 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1462 WARN_ON(ret); /* always succeed */
1466 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1467 struct nilfs_segment_buffer *last,
1468 struct inode *sufile)
1470 struct nilfs_segment_buffer *segbuf = last;
1473 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1474 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1475 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1478 nilfs_truncate_logs(&sci->sc_segbufs, last);
1482 static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1483 struct the_nilfs *nilfs, int mode)
1485 struct nilfs_cstage prev_stage = sci->sc_stage;
1488 /* Collection retry loop */
1490 sci->sc_nblk_this_inc = 0;
1491 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1493 err = nilfs_segctor_reset_segment_buffer(sci);
1497 err = nilfs_segctor_collect_blocks(sci, mode);
1498 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1502 if (unlikely(err != -E2BIG))
1505 /* The current segment is filled up */
1506 if (mode != SC_LSEG_SR ||
1507 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1510 nilfs_clear_logs(&sci->sc_segbufs);
1512 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1513 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1517 WARN_ON(err); /* do not happen */
1518 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1521 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1525 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1526 sci->sc_stage = prev_stage;
1528 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1535 static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1536 struct buffer_head *new_bh)
1538 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1540 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1541 /* The caller must release old_bh */
1545 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1546 struct nilfs_segment_buffer *segbuf,
1549 struct inode *inode = NULL;
1551 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1552 unsigned long nblocks = 0, ndatablk = 0;
1553 struct nilfs_sc_operations *sc_op = NULL;
1554 struct nilfs_segsum_pointer ssp;
1555 struct nilfs_finfo *finfo = NULL;
1556 union nilfs_binfo binfo;
1557 struct buffer_head *bh, *bh_org;
1564 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1565 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1566 ssp.offset = sizeof(struct nilfs_segment_summary);
1568 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1569 if (bh == segbuf->sb_super_root)
1572 finfo = nilfs_segctor_map_segsum_entry(
1573 sci, &ssp, sizeof(*finfo));
1574 ino = le64_to_cpu(finfo->fi_ino);
1575 nblocks = le32_to_cpu(finfo->fi_nblocks);
1576 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1578 inode = bh->b_page->mapping->host;
1580 if (mode == SC_LSEG_DSYNC)
1581 sc_op = &nilfs_sc_dsync_ops;
1582 else if (ino == NILFS_DAT_INO)
1583 sc_op = &nilfs_sc_dat_ops;
1584 else /* file blocks */
1585 sc_op = &nilfs_sc_file_ops;
1589 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1592 nilfs_list_replace_buffer(bh_org, bh);
1598 sc_op->write_data_binfo(sci, &ssp, &binfo);
1600 sc_op->write_node_binfo(sci, &ssp, &binfo);
1603 if (--nblocks == 0) {
1607 } else if (ndatablk > 0)
1617 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1619 struct nilfs_segment_buffer *segbuf;
1622 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1623 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1626 nilfs_segbuf_fill_in_segsum(segbuf);
1631 static void nilfs_begin_page_io(struct page *page)
1633 if (!page || PageWriteback(page))
1634 /* For split b-tree node pages, this function may be called
1635 twice. We ignore the 2nd or later calls by this check. */
1639 clear_page_dirty_for_io(page);
1640 set_page_writeback(page);
1644 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1646 struct nilfs_segment_buffer *segbuf;
1647 struct page *bd_page = NULL, *fs_page = NULL;
1649 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1650 struct buffer_head *bh;
1652 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1654 if (bh->b_page != bd_page) {
1657 clear_page_dirty_for_io(bd_page);
1658 set_page_writeback(bd_page);
1659 unlock_page(bd_page);
1661 bd_page = bh->b_page;
1665 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1667 set_buffer_async_write(bh);
1668 if (bh == segbuf->sb_super_root) {
1669 if (bh->b_page != bd_page) {
1671 clear_page_dirty_for_io(bd_page);
1672 set_page_writeback(bd_page);
1673 unlock_page(bd_page);
1674 bd_page = bh->b_page;
1678 if (bh->b_page != fs_page) {
1679 nilfs_begin_page_io(fs_page);
1680 fs_page = bh->b_page;
1686 clear_page_dirty_for_io(bd_page);
1687 set_page_writeback(bd_page);
1688 unlock_page(bd_page);
1690 nilfs_begin_page_io(fs_page);
1693 static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1694 struct the_nilfs *nilfs)
1698 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1699 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1703 static void nilfs_end_page_io(struct page *page, int err)
1708 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1710 * For b-tree node pages, this function may be called twice
1711 * or more because they might be split in a segment.
1713 if (PageDirty(page)) {
1715 * For pages holding split b-tree node buffers, dirty
1716 * flag on the buffers may be cleared discretely.
1717 * In that case, the page is once redirtied for
1718 * remaining buffers, and it must be cancelled if
1719 * all the buffers get cleaned later.
1722 if (nilfs_page_buffers_clean(page))
1723 __nilfs_clear_page_dirty(page);
1730 if (!nilfs_page_buffers_clean(page))
1731 __set_page_dirty_nobuffers(page);
1732 ClearPageError(page);
1734 __set_page_dirty_nobuffers(page);
1738 end_page_writeback(page);
1741 static void nilfs_abort_logs(struct list_head *logs, int err)
1743 struct nilfs_segment_buffer *segbuf;
1744 struct page *bd_page = NULL, *fs_page = NULL;
1745 struct buffer_head *bh;
1747 if (list_empty(logs))
1750 list_for_each_entry(segbuf, logs, sb_list) {
1751 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1753 if (bh->b_page != bd_page) {
1755 end_page_writeback(bd_page);
1756 bd_page = bh->b_page;
1760 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1762 clear_buffer_async_write(bh);
1763 if (bh == segbuf->sb_super_root) {
1764 if (bh->b_page != bd_page) {
1765 end_page_writeback(bd_page);
1766 bd_page = bh->b_page;
1770 if (bh->b_page != fs_page) {
1771 nilfs_end_page_io(fs_page, err);
1772 fs_page = bh->b_page;
1777 end_page_writeback(bd_page);
1779 nilfs_end_page_io(fs_page, err);
1782 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1783 struct the_nilfs *nilfs, int err)
1788 list_splice_tail_init(&sci->sc_write_logs, &logs);
1789 ret = nilfs_wait_on_logs(&logs);
1790 nilfs_abort_logs(&logs, ret ? : err);
1792 list_splice_tail_init(&sci->sc_segbufs, &logs);
1793 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1794 nilfs_free_incomplete_logs(&logs, nilfs);
1796 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1797 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1801 WARN_ON(ret); /* do not happen */
1804 nilfs_destroy_logs(&logs);
1807 static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1808 struct nilfs_segment_buffer *segbuf)
1810 nilfs->ns_segnum = segbuf->sb_segnum;
1811 nilfs->ns_nextnum = segbuf->sb_nextnum;
1812 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1813 + segbuf->sb_sum.nblocks;
1814 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1815 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1818 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1820 struct nilfs_segment_buffer *segbuf;
1821 struct page *bd_page = NULL, *fs_page = NULL;
1822 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1823 int update_sr = false;
1825 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1826 struct buffer_head *bh;
1828 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1830 set_buffer_uptodate(bh);
1831 clear_buffer_dirty(bh);
1832 if (bh->b_page != bd_page) {
1834 end_page_writeback(bd_page);
1835 bd_page = bh->b_page;
1839 * We assume that the buffers which belong to the same page
1840 * continue over the buffer list.
1841 * Under this assumption, the last BHs of pages is
1842 * identifiable by the discontinuity of bh->b_page
1843 * (page != fs_page).
1845 * For B-tree node blocks, however, this assumption is not
1846 * guaranteed. The cleanup code of B-tree node pages needs
1849 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1851 const unsigned long set_bits = (1 << BH_Uptodate);
1852 const unsigned long clear_bits =
1853 (1 << BH_Dirty | 1 << BH_Async_Write |
1854 1 << BH_Delay | 1 << BH_NILFS_Volatile |
1855 1 << BH_NILFS_Redirected);
1857 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1858 if (bh == segbuf->sb_super_root) {
1859 if (bh->b_page != bd_page) {
1860 end_page_writeback(bd_page);
1861 bd_page = bh->b_page;
1866 if (bh->b_page != fs_page) {
1867 nilfs_end_page_io(fs_page, 0);
1868 fs_page = bh->b_page;
1872 if (!nilfs_segbuf_simplex(segbuf)) {
1873 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1874 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1875 sci->sc_lseg_stime = jiffies;
1877 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1878 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1882 * Since pages may continue over multiple segment buffers,
1883 * end of the last page must be checked outside of the loop.
1886 end_page_writeback(bd_page);
1888 nilfs_end_page_io(fs_page, 0);
1890 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1892 if (nilfs_doing_gc())
1893 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1895 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1897 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1899 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1900 nilfs_set_next_segment(nilfs, segbuf);
1903 nilfs->ns_flushed_device = 0;
1904 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1905 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1907 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1908 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1909 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1910 nilfs_segctor_clear_metadata_dirty(sci);
1912 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1915 static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1919 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1921 nilfs_segctor_complete_write(sci);
1922 nilfs_destroy_logs(&sci->sc_write_logs);
1927 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1928 struct the_nilfs *nilfs)
1930 struct nilfs_inode_info *ii, *n;
1931 struct inode *ifile = sci->sc_root->ifile;
1933 spin_lock(&nilfs->ns_inode_lock);
1935 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1937 struct buffer_head *ibh;
1940 spin_unlock(&nilfs->ns_inode_lock);
1941 err = nilfs_ifile_get_inode_block(
1942 ifile, ii->vfs_inode.i_ino, &ibh);
1943 if (unlikely(err)) {
1944 nilfs_warning(sci->sc_super, __func__,
1945 "failed to get inode block.\n");
1948 mark_buffer_dirty(ibh);
1949 nilfs_mdt_mark_dirty(ifile);
1950 spin_lock(&nilfs->ns_inode_lock);
1951 if (likely(!ii->i_bh))
1958 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1959 set_bit(NILFS_I_BUSY, &ii->i_state);
1960 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1962 spin_unlock(&nilfs->ns_inode_lock);
1967 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1968 struct the_nilfs *nilfs)
1970 struct nilfs_inode_info *ii, *n;
1971 int during_mount = !(sci->sc_super->s_flags & MS_ACTIVE);
1972 int defer_iput = false;
1974 spin_lock(&nilfs->ns_inode_lock);
1975 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1976 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1977 test_bit(NILFS_I_DIRTY, &ii->i_state))
1980 clear_bit(NILFS_I_BUSY, &ii->i_state);
1983 list_del_init(&ii->i_dirty);
1984 if (!ii->vfs_inode.i_nlink || during_mount) {
1986 * Defer calling iput() to avoid deadlocks if
1987 * i_nlink == 0 or mount is not yet finished.
1989 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
1992 spin_unlock(&nilfs->ns_inode_lock);
1993 iput(&ii->vfs_inode);
1994 spin_lock(&nilfs->ns_inode_lock);
1997 spin_unlock(&nilfs->ns_inode_lock);
2000 schedule_work(&sci->sc_iput_work);
2004 * Main procedure of segment constructor
2006 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2008 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2011 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2012 sci->sc_cno = nilfs->ns_cno;
2014 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2018 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2019 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2021 if (nilfs_segctor_clean(sci))
2025 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2027 err = nilfs_segctor_begin_construction(sci, nilfs);
2031 /* Update time stamp */
2032 sci->sc_seg_ctime = get_seconds();
2034 err = nilfs_segctor_collect(sci, nilfs, mode);
2038 /* Avoid empty segment */
2039 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2040 nilfs_segbuf_empty(sci->sc_curseg)) {
2041 nilfs_segctor_abort_construction(sci, nilfs, 1);
2045 err = nilfs_segctor_assign(sci, mode);
2049 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2050 nilfs_segctor_fill_in_file_bmap(sci);
2052 if (mode == SC_LSEG_SR &&
2053 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2054 err = nilfs_segctor_fill_in_checkpoint(sci);
2056 goto failed_to_write;
2058 nilfs_segctor_fill_in_super_root(sci, nilfs);
2060 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2062 /* Write partial segments */
2063 nilfs_segctor_prepare_write(sci);
2065 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2066 nilfs->ns_crc_seed);
2068 err = nilfs_segctor_write(sci, nilfs);
2070 goto failed_to_write;
2072 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2073 nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) {
2075 * At this point, we avoid double buffering
2076 * for blocksize < pagesize because page dirty
2077 * flag is turned off during write and dirty
2078 * buffers are not properly collected for
2079 * pages crossing over segments.
2081 err = nilfs_segctor_wait(sci);
2083 goto failed_to_write;
2085 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2088 nilfs_segctor_drop_written_files(sci, nilfs);
2092 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2093 nilfs_redirty_inodes(&sci->sc_dirty_files);
2096 if (nilfs_doing_gc())
2097 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2098 nilfs_segctor_abort_construction(sci, nilfs, err);
2103 * nilfs_segctor_start_timer - set timer of background write
2104 * @sci: nilfs_sc_info
2106 * If the timer has already been set, it ignores the new request.
2107 * This function MUST be called within a section locking the segment
2110 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2112 spin_lock(&sci->sc_state_lock);
2113 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2114 sci->sc_timer.expires = jiffies + sci->sc_interval;
2115 add_timer(&sci->sc_timer);
2116 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2118 spin_unlock(&sci->sc_state_lock);
2121 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2123 spin_lock(&sci->sc_state_lock);
2124 if (!(sci->sc_flush_request & (1 << bn))) {
2125 unsigned long prev_req = sci->sc_flush_request;
2127 sci->sc_flush_request |= (1 << bn);
2129 wake_up(&sci->sc_wait_daemon);
2131 spin_unlock(&sci->sc_state_lock);
2135 * nilfs_flush_segment - trigger a segment construction for resource control
2137 * @ino: inode number of the file to be flushed out.
2139 void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2141 struct the_nilfs *nilfs = sb->s_fs_info;
2142 struct nilfs_sc_info *sci = nilfs->ns_writer;
2144 if (!sci || nilfs_doing_construction())
2146 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2147 /* assign bit 0 to data files */
2150 struct nilfs_segctor_wait_request {
2157 static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2159 struct nilfs_segctor_wait_request wait_req;
2162 spin_lock(&sci->sc_state_lock);
2163 init_wait(&wait_req.wq);
2165 atomic_set(&wait_req.done, 0);
2166 wait_req.seq = ++sci->sc_seq_request;
2167 spin_unlock(&sci->sc_state_lock);
2169 init_waitqueue_entry(&wait_req.wq, current);
2170 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2171 set_current_state(TASK_INTERRUPTIBLE);
2172 wake_up(&sci->sc_wait_daemon);
2175 if (atomic_read(&wait_req.done)) {
2179 if (!signal_pending(current)) {
2186 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2190 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2192 struct nilfs_segctor_wait_request *wrq, *n;
2193 unsigned long flags;
2195 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2196 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2198 if (!atomic_read(&wrq->done) &&
2199 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2201 atomic_set(&wrq->done, 1);
2203 if (atomic_read(&wrq->done)) {
2204 wrq->wq.func(&wrq->wq,
2205 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2209 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2213 * nilfs_construct_segment - construct a logical segment
2216 * Return Value: On success, 0 is retured. On errors, one of the following
2217 * negative error code is returned.
2219 * %-EROFS - Read only filesystem.
2223 * %-ENOSPC - No space left on device (only in a panic state).
2225 * %-ERESTARTSYS - Interrupted.
2227 * %-ENOMEM - Insufficient memory available.
2229 int nilfs_construct_segment(struct super_block *sb)
2231 struct the_nilfs *nilfs = sb->s_fs_info;
2232 struct nilfs_sc_info *sci = nilfs->ns_writer;
2233 struct nilfs_transaction_info *ti;
2239 /* A call inside transactions causes a deadlock. */
2240 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2242 err = nilfs_segctor_sync(sci);
2247 * nilfs_construct_dsync_segment - construct a data-only logical segment
2249 * @inode: inode whose data blocks should be written out
2250 * @start: start byte offset
2251 * @end: end byte offset (inclusive)
2253 * Return Value: On success, 0 is retured. On errors, one of the following
2254 * negative error code is returned.
2256 * %-EROFS - Read only filesystem.
2260 * %-ENOSPC - No space left on device (only in a panic state).
2262 * %-ERESTARTSYS - Interrupted.
2264 * %-ENOMEM - Insufficient memory available.
2266 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2267 loff_t start, loff_t end)
2269 struct the_nilfs *nilfs = sb->s_fs_info;
2270 struct nilfs_sc_info *sci = nilfs->ns_writer;
2271 struct nilfs_inode_info *ii;
2272 struct nilfs_transaction_info ti;
2278 nilfs_transaction_lock(sb, &ti, 0);
2280 ii = NILFS_I(inode);
2281 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2282 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2283 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2284 nilfs_discontinued(nilfs)) {
2285 nilfs_transaction_unlock(sb);
2286 err = nilfs_segctor_sync(sci);
2290 spin_lock(&nilfs->ns_inode_lock);
2291 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2292 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2293 spin_unlock(&nilfs->ns_inode_lock);
2294 nilfs_transaction_unlock(sb);
2297 spin_unlock(&nilfs->ns_inode_lock);
2298 sci->sc_dsync_inode = ii;
2299 sci->sc_dsync_start = start;
2300 sci->sc_dsync_end = end;
2302 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2304 nilfs->ns_flushed_device = 0;
2306 nilfs_transaction_unlock(sb);
2310 #define FLUSH_FILE_BIT (0x1) /* data file only */
2311 #define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2314 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2315 * @sci: segment constructor object
2317 static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2319 spin_lock(&sci->sc_state_lock);
2320 sci->sc_seq_accepted = sci->sc_seq_request;
2321 spin_unlock(&sci->sc_state_lock);
2322 del_timer_sync(&sci->sc_timer);
2326 * nilfs_segctor_notify - notify the result of request to caller threads
2327 * @sci: segment constructor object
2328 * @mode: mode of log forming
2329 * @err: error code to be notified
2331 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2333 /* Clear requests (even when the construction failed) */
2334 spin_lock(&sci->sc_state_lock);
2336 if (mode == SC_LSEG_SR) {
2337 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2338 sci->sc_seq_done = sci->sc_seq_accepted;
2339 nilfs_segctor_wakeup(sci, err);
2340 sci->sc_flush_request = 0;
2342 if (mode == SC_FLUSH_FILE)
2343 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2344 else if (mode == SC_FLUSH_DAT)
2345 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2347 /* re-enable timer if checkpoint creation was not done */
2348 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2349 time_before(jiffies, sci->sc_timer.expires))
2350 add_timer(&sci->sc_timer);
2352 spin_unlock(&sci->sc_state_lock);
2356 * nilfs_segctor_construct - form logs and write them to disk
2357 * @sci: segment constructor object
2358 * @mode: mode of log forming
2360 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2362 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2363 struct nilfs_super_block **sbp;
2366 nilfs_segctor_accept(sci);
2368 if (nilfs_discontinued(nilfs))
2370 if (!nilfs_segctor_confirm(sci))
2371 err = nilfs_segctor_do_construct(sci, mode);
2374 if (mode != SC_FLUSH_DAT)
2375 atomic_set(&nilfs->ns_ndirtyblks, 0);
2376 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2377 nilfs_discontinued(nilfs)) {
2378 down_write(&nilfs->ns_sem);
2380 sbp = nilfs_prepare_super(sci->sc_super,
2381 nilfs_sb_will_flip(nilfs));
2383 nilfs_set_log_cursor(sbp[0], nilfs);
2384 err = nilfs_commit_super(sci->sc_super,
2387 up_write(&nilfs->ns_sem);
2391 nilfs_segctor_notify(sci, mode, err);
2395 static void nilfs_construction_timeout(unsigned long data)
2397 struct task_struct *p = (struct task_struct *)data;
2402 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2404 struct nilfs_inode_info *ii, *n;
2406 list_for_each_entry_safe(ii, n, head, i_dirty) {
2407 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2409 list_del_init(&ii->i_dirty);
2410 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2411 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2412 iput(&ii->vfs_inode);
2416 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2419 struct the_nilfs *nilfs = sb->s_fs_info;
2420 struct nilfs_sc_info *sci = nilfs->ns_writer;
2421 struct nilfs_transaction_info ti;
2427 nilfs_transaction_lock(sb, &ti, 1);
2429 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2433 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2434 if (unlikely(err)) {
2435 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2439 sci->sc_freesegs = kbufs[4];
2440 sci->sc_nfreesegs = argv[4].v_nmembs;
2441 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2444 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2445 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2450 nilfs_warning(sb, __func__,
2451 "segment construction failed. (err=%d)", err);
2452 set_current_state(TASK_INTERRUPTIBLE);
2453 schedule_timeout(sci->sc_interval);
2455 if (nilfs_test_opt(nilfs, DISCARD)) {
2456 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2460 "NILFS warning: error %d on discard request, "
2461 "turning discards off for the device\n", ret);
2462 nilfs_clear_opt(nilfs, DISCARD);
2467 sci->sc_freesegs = NULL;
2468 sci->sc_nfreesegs = 0;
2469 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2470 nilfs_transaction_unlock(sb);
2474 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2476 struct nilfs_transaction_info ti;
2478 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2479 nilfs_segctor_construct(sci, mode);
2482 * Unclosed segment should be retried. We do this using sc_timer.
2483 * Timeout of sc_timer will invoke complete construction which leads
2484 * to close the current logical segment.
2486 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2487 nilfs_segctor_start_timer(sci);
2489 nilfs_transaction_unlock(sci->sc_super);
2492 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2496 spin_lock(&sci->sc_state_lock);
2497 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2498 SC_FLUSH_DAT : SC_FLUSH_FILE;
2499 spin_unlock(&sci->sc_state_lock);
2502 nilfs_segctor_do_construct(sci, mode);
2504 spin_lock(&sci->sc_state_lock);
2505 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2506 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2507 spin_unlock(&sci->sc_state_lock);
2509 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2512 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2514 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2515 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2516 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2517 return SC_FLUSH_FILE;
2518 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2519 return SC_FLUSH_DAT;
2525 * nilfs_segctor_thread - main loop of the segment constructor thread.
2526 * @arg: pointer to a struct nilfs_sc_info.
2528 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2529 * to execute segment constructions.
2531 static int nilfs_segctor_thread(void *arg)
2533 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2534 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2537 sci->sc_timer.data = (unsigned long)current;
2538 sci->sc_timer.function = nilfs_construction_timeout;
2541 sci->sc_task = current;
2542 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2544 "segctord starting. Construction interval = %lu seconds, "
2545 "CP frequency < %lu seconds\n",
2546 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2548 spin_lock(&sci->sc_state_lock);
2553 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2556 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2558 else if (!sci->sc_flush_request)
2561 mode = nilfs_segctor_flush_mode(sci);
2563 spin_unlock(&sci->sc_state_lock);
2564 nilfs_segctor_thread_construct(sci, mode);
2565 spin_lock(&sci->sc_state_lock);
2570 if (freezing(current)) {
2571 spin_unlock(&sci->sc_state_lock);
2573 spin_lock(&sci->sc_state_lock);
2576 int should_sleep = 1;
2578 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2579 TASK_INTERRUPTIBLE);
2581 if (sci->sc_seq_request != sci->sc_seq_done)
2583 else if (sci->sc_flush_request)
2585 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2586 should_sleep = time_before(jiffies,
2587 sci->sc_timer.expires);
2590 spin_unlock(&sci->sc_state_lock);
2592 spin_lock(&sci->sc_state_lock);
2594 finish_wait(&sci->sc_wait_daemon, &wait);
2595 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2596 time_after_eq(jiffies, sci->sc_timer.expires));
2598 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2599 set_nilfs_discontinued(nilfs);
2604 spin_unlock(&sci->sc_state_lock);
2607 sci->sc_task = NULL;
2608 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2612 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2614 struct task_struct *t;
2616 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2618 int err = PTR_ERR(t);
2620 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2624 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2628 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2629 __acquires(&sci->sc_state_lock)
2630 __releases(&sci->sc_state_lock)
2632 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2634 while (sci->sc_task) {
2635 wake_up(&sci->sc_wait_daemon);
2636 spin_unlock(&sci->sc_state_lock);
2637 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2638 spin_lock(&sci->sc_state_lock);
2643 * Setup & clean-up functions
2645 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2646 struct nilfs_root *root)
2648 struct the_nilfs *nilfs = sb->s_fs_info;
2649 struct nilfs_sc_info *sci;
2651 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2657 nilfs_get_root(root);
2658 sci->sc_root = root;
2660 init_waitqueue_head(&sci->sc_wait_request);
2661 init_waitqueue_head(&sci->sc_wait_daemon);
2662 init_waitqueue_head(&sci->sc_wait_task);
2663 spin_lock_init(&sci->sc_state_lock);
2664 INIT_LIST_HEAD(&sci->sc_dirty_files);
2665 INIT_LIST_HEAD(&sci->sc_segbufs);
2666 INIT_LIST_HEAD(&sci->sc_write_logs);
2667 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2668 INIT_LIST_HEAD(&sci->sc_iput_queue);
2669 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2670 init_timer(&sci->sc_timer);
2672 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2673 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2674 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2676 if (nilfs->ns_interval)
2677 sci->sc_interval = HZ * nilfs->ns_interval;
2678 if (nilfs->ns_watermark)
2679 sci->sc_watermark = nilfs->ns_watermark;
2683 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2685 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2687 /* The segctord thread was stopped and its timer was removed.
2688 But some tasks remain. */
2690 struct nilfs_transaction_info ti;
2692 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2693 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2694 nilfs_transaction_unlock(sci->sc_super);
2696 flush_work(&sci->sc_iput_work);
2698 } while (ret && retrycount-- > 0);
2702 * nilfs_segctor_destroy - destroy the segment constructor.
2703 * @sci: nilfs_sc_info
2705 * nilfs_segctor_destroy() kills the segctord thread and frees
2706 * the nilfs_sc_info struct.
2707 * Caller must hold the segment semaphore.
2709 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2711 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2714 up_write(&nilfs->ns_segctor_sem);
2716 spin_lock(&sci->sc_state_lock);
2717 nilfs_segctor_kill_thread(sci);
2718 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2719 || sci->sc_seq_request != sci->sc_seq_done);
2720 spin_unlock(&sci->sc_state_lock);
2722 if (flush_work(&sci->sc_iput_work))
2725 if (flag || !nilfs_segctor_confirm(sci))
2726 nilfs_segctor_write_out(sci);
2728 if (!list_empty(&sci->sc_dirty_files)) {
2729 nilfs_warning(sci->sc_super, __func__,
2730 "dirty file(s) after the final construction\n");
2731 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2734 if (!list_empty(&sci->sc_iput_queue)) {
2735 nilfs_warning(sci->sc_super, __func__,
2736 "iput queue is not empty\n");
2737 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2740 WARN_ON(!list_empty(&sci->sc_segbufs));
2741 WARN_ON(!list_empty(&sci->sc_write_logs));
2743 nilfs_put_root(sci->sc_root);
2745 down_write(&nilfs->ns_segctor_sem);
2747 del_timer_sync(&sci->sc_timer);
2752 * nilfs_attach_log_writer - attach log writer
2753 * @sb: super block instance
2754 * @root: root object of the current filesystem tree
2756 * This allocates a log writer object, initializes it, and starts the
2759 * Return Value: On success, 0 is returned. On error, one of the following
2760 * negative error code is returned.
2762 * %-ENOMEM - Insufficient memory available.
2764 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2766 struct the_nilfs *nilfs = sb->s_fs_info;
2769 if (nilfs->ns_writer) {
2771 * This happens if the filesystem was remounted
2772 * read/write after nilfs_error degenerated it into a
2775 nilfs_detach_log_writer(sb);
2778 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2779 if (!nilfs->ns_writer)
2782 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2784 kfree(nilfs->ns_writer);
2785 nilfs->ns_writer = NULL;
2791 * nilfs_detach_log_writer - destroy log writer
2792 * @sb: super block instance
2794 * This kills log writer daemon, frees the log writer object, and
2795 * destroys list of dirty files.
2797 void nilfs_detach_log_writer(struct super_block *sb)
2799 struct the_nilfs *nilfs = sb->s_fs_info;
2800 LIST_HEAD(garbage_list);
2802 down_write(&nilfs->ns_segctor_sem);
2803 if (nilfs->ns_writer) {
2804 nilfs_segctor_destroy(nilfs->ns_writer);
2805 nilfs->ns_writer = NULL;
2808 /* Force to free the list of dirty files */
2809 spin_lock(&nilfs->ns_inode_lock);
2810 if (!list_empty(&nilfs->ns_dirty_files)) {
2811 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2812 nilfs_warning(sb, __func__,
2813 "Hit dirty file after stopped log writer\n");
2815 spin_unlock(&nilfs->ns_inode_lock);
2816 up_write(&nilfs->ns_segctor_sem);
2818 nilfs_dispose_list(nilfs, &garbage_list, 1);