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 * Written by Ryusuke Konishi.
20 #include <linux/pagemap.h>
21 #include <linux/buffer_head.h>
22 #include <linux/writeback.h>
23 #include <linux/bitops.h>
24 #include <linux/bio.h>
25 #include <linux/completion.h>
26 #include <linux/blkdev.h>
27 #include <linux/backing-dev.h>
28 #include <linux/freezer.h>
29 #include <linux/kthread.h>
30 #include <linux/crc32.h>
31 #include <linux/pagevec.h>
32 #include <linux/slab.h>
46 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
48 #define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments
49 appended in collection retry loop */
51 /* Construction mode */
53 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
54 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make
55 a logical segment without a super root */
56 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without
57 creating a checkpoint */
58 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without
62 /* Stage numbers of dirty block collection */
65 NILFS_ST_GC, /* Collecting dirty blocks for GC */
71 NILFS_ST_SR, /* Super root */
72 NILFS_ST_DSYNC, /* Data sync blocks */
76 #define CREATE_TRACE_POINTS
77 #include <trace/events/nilfs2.h>
80 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
81 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
82 * the variable must use them because transition of stage count must involve
83 * trace events (trace_nilfs2_collection_stage_transition).
85 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
86 * produce tracepoint events. It is provided just for making the intention
89 static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
92 trace_nilfs2_collection_stage_transition(sci);
95 static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
97 sci->sc_stage.scnt = next_scnt;
98 trace_nilfs2_collection_stage_transition(sci);
101 static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
103 return sci->sc_stage.scnt;
106 /* State flags of collection */
107 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
108 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
109 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
110 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
112 /* Operations depending on the construction mode and file type */
113 struct nilfs_sc_operations {
114 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
116 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
118 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
120 void (*write_data_binfo)(struct nilfs_sc_info *,
121 struct nilfs_segsum_pointer *,
122 union nilfs_binfo *);
123 void (*write_node_binfo)(struct nilfs_sc_info *,
124 struct nilfs_segsum_pointer *,
125 union nilfs_binfo *);
131 static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
132 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
133 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
134 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
136 #define nilfs_cnt32_gt(a, b) \
137 (typecheck(__u32, a) && typecheck(__u32, b) && \
138 ((__s32)(b) - (__s32)(a) < 0))
139 #define nilfs_cnt32_ge(a, b) \
140 (typecheck(__u32, a) && typecheck(__u32, b) && \
141 ((__s32)(a) - (__s32)(b) >= 0))
142 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
143 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
145 static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
147 struct nilfs_transaction_info *cur_ti = current->journal_info;
151 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
152 return ++cur_ti->ti_count;
155 * If journal_info field is occupied by other FS,
156 * it is saved and will be restored on
157 * nilfs_transaction_commit().
160 "NILFS warning: journal info from a different "
162 save = current->journal_info;
166 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
169 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
175 ti->ti_magic = NILFS_TI_MAGIC;
176 current->journal_info = ti;
181 * nilfs_transaction_begin - start indivisible file operations.
183 * @ti: nilfs_transaction_info
184 * @vacancy_check: flags for vacancy rate checks
186 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
187 * the segment semaphore, to make a segment construction and write tasks
188 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
189 * The region enclosed by these two functions can be nested. To avoid a
190 * deadlock, the semaphore is only acquired or released in the outermost call.
192 * This function allocates a nilfs_transaction_info struct to keep context
193 * information on it. It is initialized and hooked onto the current task in
194 * the outermost call. If a pre-allocated struct is given to @ti, it is used
195 * instead; otherwise a new struct is assigned from a slab.
197 * When @vacancy_check flag is set, this function will check the amount of
198 * free space, and will wait for the GC to reclaim disk space if low capacity.
200 * Return Value: On success, 0 is returned. On error, one of the following
201 * negative error code is returned.
203 * %-ENOMEM - Insufficient memory available.
205 * %-ENOSPC - No space left on device
207 int nilfs_transaction_begin(struct super_block *sb,
208 struct nilfs_transaction_info *ti,
211 struct the_nilfs *nilfs;
212 int ret = nilfs_prepare_segment_lock(ti);
213 struct nilfs_transaction_info *trace_ti;
215 if (unlikely(ret < 0))
218 trace_ti = current->journal_info;
220 trace_nilfs2_transaction_transition(sb, trace_ti,
221 trace_ti->ti_count, trace_ti->ti_flags,
222 TRACE_NILFS2_TRANSACTION_BEGIN);
226 sb_start_intwrite(sb);
228 nilfs = sb->s_fs_info;
229 down_read(&nilfs->ns_segctor_sem);
230 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
231 up_read(&nilfs->ns_segctor_sem);
236 trace_ti = current->journal_info;
237 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
239 TRACE_NILFS2_TRANSACTION_BEGIN);
243 ti = current->journal_info;
244 current->journal_info = ti->ti_save;
245 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
246 kmem_cache_free(nilfs_transaction_cachep, ti);
252 * nilfs_transaction_commit - commit indivisible file operations.
255 * nilfs_transaction_commit() releases the read semaphore which is
256 * acquired by nilfs_transaction_begin(). This is only performed
257 * in outermost call of this function. If a commit flag is set,
258 * nilfs_transaction_commit() sets a timer to start the segment
259 * constructor. If a sync flag is set, it starts construction
262 int nilfs_transaction_commit(struct super_block *sb)
264 struct nilfs_transaction_info *ti = current->journal_info;
265 struct the_nilfs *nilfs = sb->s_fs_info;
268 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
269 ti->ti_flags |= NILFS_TI_COMMIT;
270 if (ti->ti_count > 0) {
272 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
273 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
276 if (nilfs->ns_writer) {
277 struct nilfs_sc_info *sci = nilfs->ns_writer;
279 if (ti->ti_flags & NILFS_TI_COMMIT)
280 nilfs_segctor_start_timer(sci);
281 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
282 nilfs_segctor_do_flush(sci, 0);
284 up_read(&nilfs->ns_segctor_sem);
285 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
286 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
288 current->journal_info = ti->ti_save;
290 if (ti->ti_flags & NILFS_TI_SYNC)
291 err = nilfs_construct_segment(sb);
292 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
293 kmem_cache_free(nilfs_transaction_cachep, ti);
298 void nilfs_transaction_abort(struct super_block *sb)
300 struct nilfs_transaction_info *ti = current->journal_info;
301 struct the_nilfs *nilfs = sb->s_fs_info;
303 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
304 if (ti->ti_count > 0) {
306 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
307 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
310 up_read(&nilfs->ns_segctor_sem);
312 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
313 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
315 current->journal_info = ti->ti_save;
316 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
317 kmem_cache_free(nilfs_transaction_cachep, ti);
321 void nilfs_relax_pressure_in_lock(struct super_block *sb)
323 struct the_nilfs *nilfs = sb->s_fs_info;
324 struct nilfs_sc_info *sci = nilfs->ns_writer;
326 if (!sci || !sci->sc_flush_request)
329 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
330 up_read(&nilfs->ns_segctor_sem);
332 down_write(&nilfs->ns_segctor_sem);
333 if (sci->sc_flush_request &&
334 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
335 struct nilfs_transaction_info *ti = current->journal_info;
337 ti->ti_flags |= NILFS_TI_WRITER;
338 nilfs_segctor_do_immediate_flush(sci);
339 ti->ti_flags &= ~NILFS_TI_WRITER;
341 downgrade_write(&nilfs->ns_segctor_sem);
344 static void nilfs_transaction_lock(struct super_block *sb,
345 struct nilfs_transaction_info *ti,
348 struct nilfs_transaction_info *cur_ti = current->journal_info;
349 struct the_nilfs *nilfs = sb->s_fs_info;
350 struct nilfs_sc_info *sci = nilfs->ns_writer;
353 ti->ti_flags = NILFS_TI_WRITER;
355 ti->ti_save = cur_ti;
356 ti->ti_magic = NILFS_TI_MAGIC;
357 current->journal_info = ti;
360 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
361 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
363 down_write(&nilfs->ns_segctor_sem);
364 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
367 nilfs_segctor_do_immediate_flush(sci);
369 up_write(&nilfs->ns_segctor_sem);
373 ti->ti_flags |= NILFS_TI_GC;
375 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
376 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
379 static void nilfs_transaction_unlock(struct super_block *sb)
381 struct nilfs_transaction_info *ti = current->journal_info;
382 struct the_nilfs *nilfs = sb->s_fs_info;
384 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
385 BUG_ON(ti->ti_count > 0);
387 up_write(&nilfs->ns_segctor_sem);
388 current->journal_info = ti->ti_save;
390 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
391 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
394 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
395 struct nilfs_segsum_pointer *ssp,
398 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
399 unsigned int blocksize = sci->sc_super->s_blocksize;
402 if (unlikely(ssp->offset + bytes > blocksize)) {
404 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
405 &segbuf->sb_segsum_buffers));
406 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
408 p = ssp->bh->b_data + ssp->offset;
409 ssp->offset += bytes;
414 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
415 * @sci: nilfs_sc_info
417 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
419 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
420 struct buffer_head *sumbh;
421 unsigned int sumbytes;
422 unsigned int flags = 0;
425 if (nilfs_doing_gc())
427 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
431 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
432 sumbytes = segbuf->sb_sum.sumbytes;
433 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
434 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
435 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
439 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
441 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
442 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
443 return -E2BIG; /* The current segment is filled up
445 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
446 return nilfs_segctor_reset_segment_buffer(sci);
449 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
451 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
454 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
455 err = nilfs_segctor_feed_segment(sci);
458 segbuf = sci->sc_curseg;
460 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
462 segbuf->sb_sum.flags |= NILFS_SS_SR;
467 * Functions for making segment summary and payloads
469 static int nilfs_segctor_segsum_block_required(
470 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
471 unsigned int binfo_size)
473 unsigned int blocksize = sci->sc_super->s_blocksize;
474 /* Size of finfo and binfo is enough small against blocksize */
476 return ssp->offset + binfo_size +
477 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
481 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
484 sci->sc_curseg->sb_sum.nfinfo++;
485 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
486 nilfs_segctor_map_segsum_entry(
487 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
489 if (NILFS_I(inode)->i_root &&
490 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
491 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
495 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
498 struct nilfs_finfo *finfo;
499 struct nilfs_inode_info *ii;
500 struct nilfs_segment_buffer *segbuf;
503 if (sci->sc_blk_cnt == 0)
508 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
510 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
515 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
517 finfo->fi_ino = cpu_to_le64(inode->i_ino);
518 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
519 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
520 finfo->fi_cno = cpu_to_le64(cno);
522 segbuf = sci->sc_curseg;
523 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
524 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
525 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
526 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
529 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
530 struct buffer_head *bh,
532 unsigned int binfo_size)
534 struct nilfs_segment_buffer *segbuf;
535 int required, err = 0;
538 segbuf = sci->sc_curseg;
539 required = nilfs_segctor_segsum_block_required(
540 sci, &sci->sc_binfo_ptr, binfo_size);
541 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
542 nilfs_segctor_end_finfo(sci, inode);
543 err = nilfs_segctor_feed_segment(sci);
548 if (unlikely(required)) {
549 err = nilfs_segbuf_extend_segsum(segbuf);
553 if (sci->sc_blk_cnt == 0)
554 nilfs_segctor_begin_finfo(sci, inode);
556 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
557 /* Substitution to vblocknr is delayed until update_blocknr() */
558 nilfs_segbuf_add_file_buffer(segbuf, bh);
565 * Callback functions that enumerate, mark, and collect dirty blocks
567 static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
568 struct buffer_head *bh, struct inode *inode)
572 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
576 err = nilfs_segctor_add_file_block(sci, bh, inode,
577 sizeof(struct nilfs_binfo_v));
579 sci->sc_datablk_cnt++;
583 static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
584 struct buffer_head *bh,
587 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
590 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
591 struct buffer_head *bh,
594 WARN_ON(!buffer_dirty(bh));
595 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
598 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
599 struct nilfs_segsum_pointer *ssp,
600 union nilfs_binfo *binfo)
602 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
603 sci, ssp, sizeof(*binfo_v));
604 *binfo_v = binfo->bi_v;
607 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
608 struct nilfs_segsum_pointer *ssp,
609 union nilfs_binfo *binfo)
611 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
612 sci, ssp, sizeof(*vblocknr));
613 *vblocknr = binfo->bi_v.bi_vblocknr;
616 static const struct nilfs_sc_operations nilfs_sc_file_ops = {
617 .collect_data = nilfs_collect_file_data,
618 .collect_node = nilfs_collect_file_node,
619 .collect_bmap = nilfs_collect_file_bmap,
620 .write_data_binfo = nilfs_write_file_data_binfo,
621 .write_node_binfo = nilfs_write_file_node_binfo,
624 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
625 struct buffer_head *bh, struct inode *inode)
629 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
633 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
635 sci->sc_datablk_cnt++;
639 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
640 struct buffer_head *bh, struct inode *inode)
642 WARN_ON(!buffer_dirty(bh));
643 return nilfs_segctor_add_file_block(sci, bh, inode,
644 sizeof(struct nilfs_binfo_dat));
647 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
648 struct nilfs_segsum_pointer *ssp,
649 union nilfs_binfo *binfo)
651 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
653 *blkoff = binfo->bi_dat.bi_blkoff;
656 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
657 struct nilfs_segsum_pointer *ssp,
658 union nilfs_binfo *binfo)
660 struct nilfs_binfo_dat *binfo_dat =
661 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
662 *binfo_dat = binfo->bi_dat;
665 static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
666 .collect_data = nilfs_collect_dat_data,
667 .collect_node = nilfs_collect_file_node,
668 .collect_bmap = nilfs_collect_dat_bmap,
669 .write_data_binfo = nilfs_write_dat_data_binfo,
670 .write_node_binfo = nilfs_write_dat_node_binfo,
673 static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
674 .collect_data = nilfs_collect_file_data,
675 .collect_node = NULL,
676 .collect_bmap = NULL,
677 .write_data_binfo = nilfs_write_file_data_binfo,
678 .write_node_binfo = NULL,
681 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
682 struct list_head *listp,
684 loff_t start, loff_t end)
686 struct address_space *mapping = inode->i_mapping;
688 pgoff_t index = 0, last = ULONG_MAX;
692 if (unlikely(start != 0 || end != LLONG_MAX)) {
694 * A valid range is given for sync-ing data pages. The
695 * range is rounded to per-page; extra dirty buffers
696 * may be included if blocksize < pagesize.
698 index = start >> PAGE_SHIFT;
699 last = end >> PAGE_SHIFT;
701 pagevec_init(&pvec, 0);
703 if (unlikely(index > last) ||
704 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
705 min_t(pgoff_t, last - index,
706 PAGEVEC_SIZE - 1) + 1))
709 for (i = 0; i < pagevec_count(&pvec); i++) {
710 struct buffer_head *bh, *head;
711 struct page *page = pvec.pages[i];
713 if (unlikely(page->index > last))
717 if (!page_has_buffers(page))
718 create_empty_buffers(page, 1 << inode->i_blkbits, 0);
721 bh = head = page_buffers(page);
723 if (!buffer_dirty(bh) || buffer_async_write(bh))
726 list_add_tail(&bh->b_assoc_buffers, listp);
728 if (unlikely(ndirties >= nlimit)) {
729 pagevec_release(&pvec);
733 } while (bh = bh->b_this_page, bh != head);
735 pagevec_release(&pvec);
740 static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
741 struct list_head *listp)
743 struct nilfs_inode_info *ii = NILFS_I(inode);
744 struct address_space *mapping = &ii->i_btnode_cache;
746 struct buffer_head *bh, *head;
750 pagevec_init(&pvec, 0);
752 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
754 for (i = 0; i < pagevec_count(&pvec); i++) {
755 bh = head = page_buffers(pvec.pages[i]);
757 if (buffer_dirty(bh) &&
758 !buffer_async_write(bh)) {
760 list_add_tail(&bh->b_assoc_buffers,
763 bh = bh->b_this_page;
764 } while (bh != head);
766 pagevec_release(&pvec);
771 static void nilfs_dispose_list(struct the_nilfs *nilfs,
772 struct list_head *head, int force)
774 struct nilfs_inode_info *ii, *n;
775 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
778 while (!list_empty(head)) {
779 spin_lock(&nilfs->ns_inode_lock);
780 list_for_each_entry_safe(ii, n, head, i_dirty) {
781 list_del_init(&ii->i_dirty);
783 if (unlikely(ii->i_bh)) {
787 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
788 set_bit(NILFS_I_QUEUED, &ii->i_state);
789 list_add_tail(&ii->i_dirty,
790 &nilfs->ns_dirty_files);
794 if (nv == SC_N_INODEVEC)
797 spin_unlock(&nilfs->ns_inode_lock);
799 for (pii = ivec; nv > 0; pii++, nv--)
800 iput(&(*pii)->vfs_inode);
804 static void nilfs_iput_work_func(struct work_struct *work)
806 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
808 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
810 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
813 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
814 struct nilfs_root *root)
818 if (nilfs_mdt_fetch_dirty(root->ifile))
820 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
822 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
824 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
829 static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
831 return list_empty(&sci->sc_dirty_files) &&
832 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
833 sci->sc_nfreesegs == 0 &&
834 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
837 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
839 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
842 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
843 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
845 spin_lock(&nilfs->ns_inode_lock);
846 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
849 spin_unlock(&nilfs->ns_inode_lock);
853 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
855 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
857 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
858 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
859 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
860 nilfs_mdt_clear_dirty(nilfs->ns_dat);
863 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
865 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
866 struct buffer_head *bh_cp;
867 struct nilfs_checkpoint *raw_cp;
870 /* XXX: this interface will be changed */
871 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
874 /* The following code is duplicated with cpfile. But, it is
875 needed to collect the checkpoint even if it was not newly
877 mark_buffer_dirty(bh_cp);
878 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
879 nilfs_cpfile_put_checkpoint(
880 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
882 WARN_ON(err == -EINVAL || err == -ENOENT);
887 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
889 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
890 struct buffer_head *bh_cp;
891 struct nilfs_checkpoint *raw_cp;
894 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
897 WARN_ON(err == -EINVAL || err == -ENOENT);
900 raw_cp->cp_snapshot_list.ssl_next = 0;
901 raw_cp->cp_snapshot_list.ssl_prev = 0;
902 raw_cp->cp_inodes_count =
903 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
904 raw_cp->cp_blocks_count =
905 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
906 raw_cp->cp_nblk_inc =
907 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
908 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
909 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
911 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
912 nilfs_checkpoint_clear_minor(raw_cp);
914 nilfs_checkpoint_set_minor(raw_cp);
916 nilfs_write_inode_common(sci->sc_root->ifile,
917 &raw_cp->cp_ifile_inode, 1);
918 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
925 static void nilfs_fill_in_file_bmap(struct inode *ifile,
926 struct nilfs_inode_info *ii)
929 struct buffer_head *ibh;
930 struct nilfs_inode *raw_inode;
932 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
935 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
937 nilfs_bmap_write(ii->i_bmap, raw_inode);
938 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
942 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
944 struct nilfs_inode_info *ii;
946 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
947 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
948 set_bit(NILFS_I_COLLECTED, &ii->i_state);
952 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
953 struct the_nilfs *nilfs)
955 struct buffer_head *bh_sr;
956 struct nilfs_super_root *raw_sr;
957 unsigned int isz, srsz;
959 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
960 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
961 isz = nilfs->ns_inode_size;
962 srsz = NILFS_SR_BYTES(isz);
964 raw_sr->sr_bytes = cpu_to_le16(srsz);
965 raw_sr->sr_nongc_ctime
966 = cpu_to_le64(nilfs_doing_gc() ?
967 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
968 raw_sr->sr_flags = 0;
970 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
971 NILFS_SR_DAT_OFFSET(isz), 1);
972 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
973 NILFS_SR_CPFILE_OFFSET(isz), 1);
974 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
975 NILFS_SR_SUFILE_OFFSET(isz), 1);
976 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
979 static void nilfs_redirty_inodes(struct list_head *head)
981 struct nilfs_inode_info *ii;
983 list_for_each_entry(ii, head, i_dirty) {
984 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
985 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
989 static void nilfs_drop_collected_inodes(struct list_head *head)
991 struct nilfs_inode_info *ii;
993 list_for_each_entry(ii, head, i_dirty) {
994 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
997 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
998 set_bit(NILFS_I_UPDATED, &ii->i_state);
1002 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1003 struct inode *inode,
1004 struct list_head *listp,
1005 int (*collect)(struct nilfs_sc_info *,
1006 struct buffer_head *,
1009 struct buffer_head *bh, *n;
1013 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1014 list_del_init(&bh->b_assoc_buffers);
1015 err = collect(sci, bh, inode);
1018 goto dispose_buffers;
1024 while (!list_empty(listp)) {
1025 bh = list_first_entry(listp, struct buffer_head,
1027 list_del_init(&bh->b_assoc_buffers);
1033 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1035 /* Remaining number of blocks within segment buffer */
1036 return sci->sc_segbuf_nblocks -
1037 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1040 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1041 struct inode *inode,
1042 const struct nilfs_sc_operations *sc_ops)
1044 LIST_HEAD(data_buffers);
1045 LIST_HEAD(node_buffers);
1048 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1049 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1051 n = nilfs_lookup_dirty_data_buffers(
1052 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1054 err = nilfs_segctor_apply_buffers(
1055 sci, inode, &data_buffers,
1056 sc_ops->collect_data);
1057 BUG_ON(!err); /* always receive -E2BIG or true error */
1061 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1063 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1064 err = nilfs_segctor_apply_buffers(
1065 sci, inode, &data_buffers, sc_ops->collect_data);
1066 if (unlikely(err)) {
1067 /* dispose node list */
1068 nilfs_segctor_apply_buffers(
1069 sci, inode, &node_buffers, NULL);
1072 sci->sc_stage.flags |= NILFS_CF_NODE;
1075 err = nilfs_segctor_apply_buffers(
1076 sci, inode, &node_buffers, sc_ops->collect_node);
1080 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1081 err = nilfs_segctor_apply_buffers(
1082 sci, inode, &node_buffers, sc_ops->collect_bmap);
1086 nilfs_segctor_end_finfo(sci, inode);
1087 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1093 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1094 struct inode *inode)
1096 LIST_HEAD(data_buffers);
1097 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1100 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1101 sci->sc_dsync_start,
1104 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1105 nilfs_collect_file_data);
1107 nilfs_segctor_end_finfo(sci, inode);
1109 /* always receive -E2BIG or true error if n > rest */
1114 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1116 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1117 struct list_head *head;
1118 struct nilfs_inode_info *ii;
1122 switch (nilfs_sc_cstage_get(sci)) {
1125 sci->sc_stage.flags = 0;
1127 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1128 sci->sc_nblk_inc = 0;
1129 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1130 if (mode == SC_LSEG_DSYNC) {
1131 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1136 sci->sc_stage.dirty_file_ptr = NULL;
1137 sci->sc_stage.gc_inode_ptr = NULL;
1138 if (mode == SC_FLUSH_DAT) {
1139 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1142 nilfs_sc_cstage_inc(sci); /* Fall through */
1144 if (nilfs_doing_gc()) {
1145 head = &sci->sc_gc_inodes;
1146 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1148 list_for_each_entry_continue(ii, head, i_dirty) {
1149 err = nilfs_segctor_scan_file(
1150 sci, &ii->vfs_inode,
1151 &nilfs_sc_file_ops);
1152 if (unlikely(err)) {
1153 sci->sc_stage.gc_inode_ptr = list_entry(
1155 struct nilfs_inode_info,
1159 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1161 sci->sc_stage.gc_inode_ptr = NULL;
1163 nilfs_sc_cstage_inc(sci); /* Fall through */
1165 head = &sci->sc_dirty_files;
1166 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1168 list_for_each_entry_continue(ii, head, i_dirty) {
1169 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1171 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1172 &nilfs_sc_file_ops);
1173 if (unlikely(err)) {
1174 sci->sc_stage.dirty_file_ptr =
1175 list_entry(ii->i_dirty.prev,
1176 struct nilfs_inode_info,
1180 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1181 /* XXX: required ? */
1183 sci->sc_stage.dirty_file_ptr = NULL;
1184 if (mode == SC_FLUSH_FILE) {
1185 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1188 nilfs_sc_cstage_inc(sci);
1189 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1191 case NILFS_ST_IFILE:
1192 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1193 &nilfs_sc_file_ops);
1196 nilfs_sc_cstage_inc(sci);
1197 /* Creating a checkpoint */
1198 err = nilfs_segctor_create_checkpoint(sci);
1202 case NILFS_ST_CPFILE:
1203 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1204 &nilfs_sc_file_ops);
1207 nilfs_sc_cstage_inc(sci); /* Fall through */
1208 case NILFS_ST_SUFILE:
1209 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1210 sci->sc_nfreesegs, &ndone);
1211 if (unlikely(err)) {
1212 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1213 sci->sc_freesegs, ndone,
1217 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1219 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1220 &nilfs_sc_file_ops);
1223 nilfs_sc_cstage_inc(sci); /* Fall through */
1226 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1230 if (mode == SC_FLUSH_DAT) {
1231 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1234 nilfs_sc_cstage_inc(sci); /* Fall through */
1236 if (mode == SC_LSEG_SR) {
1237 /* Appending a super root */
1238 err = nilfs_segctor_add_super_root(sci);
1242 /* End of a logical segment */
1243 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1244 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1246 case NILFS_ST_DSYNC:
1248 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1249 ii = sci->sc_dsync_inode;
1250 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1253 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1256 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1257 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1270 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1271 * @sci: nilfs_sc_info
1272 * @nilfs: nilfs object
1274 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1275 struct the_nilfs *nilfs)
1277 struct nilfs_segment_buffer *segbuf, *prev;
1281 segbuf = nilfs_segbuf_new(sci->sc_super);
1282 if (unlikely(!segbuf))
1285 if (list_empty(&sci->sc_write_logs)) {
1286 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1287 nilfs->ns_pseg_offset, nilfs);
1288 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1289 nilfs_shift_to_next_segment(nilfs);
1290 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1293 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1294 nextnum = nilfs->ns_nextnum;
1296 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1297 /* Start from the head of a new full segment */
1301 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1302 nilfs_segbuf_map_cont(segbuf, prev);
1303 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1304 nextnum = prev->sb_nextnum;
1306 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1307 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1308 segbuf->sb_sum.seg_seq++;
1313 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1318 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1322 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1324 BUG_ON(!list_empty(&sci->sc_segbufs));
1325 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1326 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1330 nilfs_segbuf_free(segbuf);
1334 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1335 struct the_nilfs *nilfs, int nadd)
1337 struct nilfs_segment_buffer *segbuf, *prev;
1338 struct inode *sufile = nilfs->ns_sufile;
1343 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1345 * Since the segment specified with nextnum might be allocated during
1346 * the previous construction, the buffer including its segusage may
1347 * not be dirty. The following call ensures that the buffer is dirty
1348 * and will pin the buffer on memory until the sufile is written.
1350 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1354 for (i = 0; i < nadd; i++) {
1355 /* extend segment info */
1357 segbuf = nilfs_segbuf_new(sci->sc_super);
1358 if (unlikely(!segbuf))
1361 /* map this buffer to region of segment on-disk */
1362 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1363 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1365 /* allocate the next next full segment */
1366 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1370 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1371 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1373 list_add_tail(&segbuf->sb_list, &list);
1376 list_splice_tail(&list, &sci->sc_segbufs);
1380 nilfs_segbuf_free(segbuf);
1382 list_for_each_entry(segbuf, &list, sb_list) {
1383 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1384 WARN_ON(ret); /* never fails */
1386 nilfs_destroy_logs(&list);
1390 static void nilfs_free_incomplete_logs(struct list_head *logs,
1391 struct the_nilfs *nilfs)
1393 struct nilfs_segment_buffer *segbuf, *prev;
1394 struct inode *sufile = nilfs->ns_sufile;
1397 segbuf = NILFS_FIRST_SEGBUF(logs);
1398 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1399 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1400 WARN_ON(ret); /* never fails */
1402 if (atomic_read(&segbuf->sb_err)) {
1403 /* Case 1: The first segment failed */
1404 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1405 /* Case 1a: Partial segment appended into an existing
1407 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1408 segbuf->sb_fseg_end);
1409 else /* Case 1b: New full segment */
1410 set_nilfs_discontinued(nilfs);
1414 list_for_each_entry_continue(segbuf, logs, sb_list) {
1415 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1416 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1417 WARN_ON(ret); /* never fails */
1419 if (atomic_read(&segbuf->sb_err) &&
1420 segbuf->sb_segnum != nilfs->ns_nextnum)
1421 /* Case 2: extended segment (!= next) failed */
1422 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1427 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1428 struct inode *sufile)
1430 struct nilfs_segment_buffer *segbuf;
1431 unsigned long live_blocks;
1434 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1435 live_blocks = segbuf->sb_sum.nblocks +
1436 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1437 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1440 WARN_ON(ret); /* always succeed because the segusage is dirty */
1444 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1446 struct nilfs_segment_buffer *segbuf;
1449 segbuf = NILFS_FIRST_SEGBUF(logs);
1450 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1451 segbuf->sb_pseg_start -
1452 segbuf->sb_fseg_start, 0);
1453 WARN_ON(ret); /* always succeed because the segusage is dirty */
1455 list_for_each_entry_continue(segbuf, logs, sb_list) {
1456 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1458 WARN_ON(ret); /* always succeed */
1462 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1463 struct nilfs_segment_buffer *last,
1464 struct inode *sufile)
1466 struct nilfs_segment_buffer *segbuf = last;
1469 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1470 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1471 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1474 nilfs_truncate_logs(&sci->sc_segbufs, last);
1478 static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1479 struct the_nilfs *nilfs, int mode)
1481 struct nilfs_cstage prev_stage = sci->sc_stage;
1484 /* Collection retry loop */
1486 sci->sc_nblk_this_inc = 0;
1487 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1489 err = nilfs_segctor_reset_segment_buffer(sci);
1493 err = nilfs_segctor_collect_blocks(sci, mode);
1494 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1498 if (unlikely(err != -E2BIG))
1501 /* The current segment is filled up */
1502 if (mode != SC_LSEG_SR ||
1503 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1506 nilfs_clear_logs(&sci->sc_segbufs);
1508 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1509 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1513 WARN_ON(err); /* do not happen */
1514 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1517 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1521 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1522 sci->sc_stage = prev_stage;
1524 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1531 static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1532 struct buffer_head *new_bh)
1534 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1536 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1537 /* The caller must release old_bh */
1541 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1542 struct nilfs_segment_buffer *segbuf,
1545 struct inode *inode = NULL;
1547 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1548 unsigned long nblocks = 0, ndatablk = 0;
1549 const struct nilfs_sc_operations *sc_op = NULL;
1550 struct nilfs_segsum_pointer ssp;
1551 struct nilfs_finfo *finfo = NULL;
1552 union nilfs_binfo binfo;
1553 struct buffer_head *bh, *bh_org;
1560 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1561 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1562 ssp.offset = sizeof(struct nilfs_segment_summary);
1564 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1565 if (bh == segbuf->sb_super_root)
1568 finfo = nilfs_segctor_map_segsum_entry(
1569 sci, &ssp, sizeof(*finfo));
1570 ino = le64_to_cpu(finfo->fi_ino);
1571 nblocks = le32_to_cpu(finfo->fi_nblocks);
1572 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1574 inode = bh->b_page->mapping->host;
1576 if (mode == SC_LSEG_DSYNC)
1577 sc_op = &nilfs_sc_dsync_ops;
1578 else if (ino == NILFS_DAT_INO)
1579 sc_op = &nilfs_sc_dat_ops;
1580 else /* file blocks */
1581 sc_op = &nilfs_sc_file_ops;
1585 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1588 nilfs_list_replace_buffer(bh_org, bh);
1594 sc_op->write_data_binfo(sci, &ssp, &binfo);
1596 sc_op->write_node_binfo(sci, &ssp, &binfo);
1599 if (--nblocks == 0) {
1603 } else if (ndatablk > 0)
1613 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1615 struct nilfs_segment_buffer *segbuf;
1618 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1619 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1622 nilfs_segbuf_fill_in_segsum(segbuf);
1627 static void nilfs_begin_page_io(struct page *page)
1629 if (!page || PageWriteback(page))
1630 /* For split b-tree node pages, this function may be called
1631 twice. We ignore the 2nd or later calls by this check. */
1635 clear_page_dirty_for_io(page);
1636 set_page_writeback(page);
1640 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1642 struct nilfs_segment_buffer *segbuf;
1643 struct page *bd_page = NULL, *fs_page = NULL;
1645 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1646 struct buffer_head *bh;
1648 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1650 if (bh->b_page != bd_page) {
1653 clear_page_dirty_for_io(bd_page);
1654 set_page_writeback(bd_page);
1655 unlock_page(bd_page);
1657 bd_page = bh->b_page;
1661 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1663 set_buffer_async_write(bh);
1664 if (bh == segbuf->sb_super_root) {
1665 if (bh->b_page != bd_page) {
1667 clear_page_dirty_for_io(bd_page);
1668 set_page_writeback(bd_page);
1669 unlock_page(bd_page);
1670 bd_page = bh->b_page;
1674 if (bh->b_page != fs_page) {
1675 nilfs_begin_page_io(fs_page);
1676 fs_page = bh->b_page;
1682 clear_page_dirty_for_io(bd_page);
1683 set_page_writeback(bd_page);
1684 unlock_page(bd_page);
1686 nilfs_begin_page_io(fs_page);
1689 static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1690 struct the_nilfs *nilfs)
1694 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1695 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1699 static void nilfs_end_page_io(struct page *page, int err)
1704 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1706 * For b-tree node pages, this function may be called twice
1707 * or more because they might be split in a segment.
1709 if (PageDirty(page)) {
1711 * For pages holding split b-tree node buffers, dirty
1712 * flag on the buffers may be cleared discretely.
1713 * In that case, the page is once redirtied for
1714 * remaining buffers, and it must be cancelled if
1715 * all the buffers get cleaned later.
1718 if (nilfs_page_buffers_clean(page))
1719 __nilfs_clear_page_dirty(page);
1726 if (!nilfs_page_buffers_clean(page))
1727 __set_page_dirty_nobuffers(page);
1728 ClearPageError(page);
1730 __set_page_dirty_nobuffers(page);
1734 end_page_writeback(page);
1737 static void nilfs_abort_logs(struct list_head *logs, int err)
1739 struct nilfs_segment_buffer *segbuf;
1740 struct page *bd_page = NULL, *fs_page = NULL;
1741 struct buffer_head *bh;
1743 if (list_empty(logs))
1746 list_for_each_entry(segbuf, logs, sb_list) {
1747 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1749 if (bh->b_page != bd_page) {
1751 end_page_writeback(bd_page);
1752 bd_page = bh->b_page;
1756 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1758 clear_buffer_async_write(bh);
1759 if (bh == segbuf->sb_super_root) {
1760 if (bh->b_page != bd_page) {
1761 end_page_writeback(bd_page);
1762 bd_page = bh->b_page;
1766 if (bh->b_page != fs_page) {
1767 nilfs_end_page_io(fs_page, err);
1768 fs_page = bh->b_page;
1773 end_page_writeback(bd_page);
1775 nilfs_end_page_io(fs_page, err);
1778 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1779 struct the_nilfs *nilfs, int err)
1784 list_splice_tail_init(&sci->sc_write_logs, &logs);
1785 ret = nilfs_wait_on_logs(&logs);
1786 nilfs_abort_logs(&logs, ret ? : err);
1788 list_splice_tail_init(&sci->sc_segbufs, &logs);
1789 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1790 nilfs_free_incomplete_logs(&logs, nilfs);
1792 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1793 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1797 WARN_ON(ret); /* do not happen */
1800 nilfs_destroy_logs(&logs);
1803 static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1804 struct nilfs_segment_buffer *segbuf)
1806 nilfs->ns_segnum = segbuf->sb_segnum;
1807 nilfs->ns_nextnum = segbuf->sb_nextnum;
1808 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1809 + segbuf->sb_sum.nblocks;
1810 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1811 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1814 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1816 struct nilfs_segment_buffer *segbuf;
1817 struct page *bd_page = NULL, *fs_page = NULL;
1818 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1819 int update_sr = false;
1821 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1822 struct buffer_head *bh;
1824 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1826 set_buffer_uptodate(bh);
1827 clear_buffer_dirty(bh);
1828 if (bh->b_page != bd_page) {
1830 end_page_writeback(bd_page);
1831 bd_page = bh->b_page;
1835 * We assume that the buffers which belong to the same page
1836 * continue over the buffer list.
1837 * Under this assumption, the last BHs of pages is
1838 * identifiable by the discontinuity of bh->b_page
1839 * (page != fs_page).
1841 * For B-tree node blocks, however, this assumption is not
1842 * guaranteed. The cleanup code of B-tree node pages needs
1845 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1847 const unsigned long set_bits = (1 << BH_Uptodate);
1848 const unsigned long clear_bits =
1849 (1 << BH_Dirty | 1 << BH_Async_Write |
1850 1 << BH_Delay | 1 << BH_NILFS_Volatile |
1851 1 << BH_NILFS_Redirected);
1853 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1854 if (bh == segbuf->sb_super_root) {
1855 if (bh->b_page != bd_page) {
1856 end_page_writeback(bd_page);
1857 bd_page = bh->b_page;
1862 if (bh->b_page != fs_page) {
1863 nilfs_end_page_io(fs_page, 0);
1864 fs_page = bh->b_page;
1868 if (!nilfs_segbuf_simplex(segbuf)) {
1869 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1870 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1871 sci->sc_lseg_stime = jiffies;
1873 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1874 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1878 * Since pages may continue over multiple segment buffers,
1879 * end of the last page must be checked outside of the loop.
1882 end_page_writeback(bd_page);
1884 nilfs_end_page_io(fs_page, 0);
1886 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1888 if (nilfs_doing_gc())
1889 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1891 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1893 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1895 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1896 nilfs_set_next_segment(nilfs, segbuf);
1899 nilfs->ns_flushed_device = 0;
1900 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1901 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1903 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1904 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1905 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1906 nilfs_segctor_clear_metadata_dirty(sci);
1908 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1911 static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1915 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1917 nilfs_segctor_complete_write(sci);
1918 nilfs_destroy_logs(&sci->sc_write_logs);
1923 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1924 struct the_nilfs *nilfs)
1926 struct nilfs_inode_info *ii, *n;
1927 struct inode *ifile = sci->sc_root->ifile;
1929 spin_lock(&nilfs->ns_inode_lock);
1931 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1933 struct buffer_head *ibh;
1936 spin_unlock(&nilfs->ns_inode_lock);
1937 err = nilfs_ifile_get_inode_block(
1938 ifile, ii->vfs_inode.i_ino, &ibh);
1939 if (unlikely(err)) {
1940 nilfs_warning(sci->sc_super, __func__,
1941 "failed to get inode block.");
1944 mark_buffer_dirty(ibh);
1945 nilfs_mdt_mark_dirty(ifile);
1946 spin_lock(&nilfs->ns_inode_lock);
1947 if (likely(!ii->i_bh))
1954 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1955 set_bit(NILFS_I_BUSY, &ii->i_state);
1956 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1958 spin_unlock(&nilfs->ns_inode_lock);
1963 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1964 struct the_nilfs *nilfs)
1966 struct nilfs_inode_info *ii, *n;
1967 int during_mount = !(sci->sc_super->s_flags & MS_ACTIVE);
1968 int defer_iput = false;
1970 spin_lock(&nilfs->ns_inode_lock);
1971 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1972 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1973 test_bit(NILFS_I_DIRTY, &ii->i_state))
1976 clear_bit(NILFS_I_BUSY, &ii->i_state);
1979 list_del_init(&ii->i_dirty);
1980 if (!ii->vfs_inode.i_nlink || during_mount) {
1982 * Defer calling iput() to avoid deadlocks if
1983 * i_nlink == 0 or mount is not yet finished.
1985 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
1988 spin_unlock(&nilfs->ns_inode_lock);
1989 iput(&ii->vfs_inode);
1990 spin_lock(&nilfs->ns_inode_lock);
1993 spin_unlock(&nilfs->ns_inode_lock);
1996 schedule_work(&sci->sc_iput_work);
2000 * Main procedure of segment constructor
2002 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2004 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2007 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2008 sci->sc_cno = nilfs->ns_cno;
2010 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2014 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2015 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2017 if (nilfs_segctor_clean(sci))
2021 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2023 err = nilfs_segctor_begin_construction(sci, nilfs);
2027 /* Update time stamp */
2028 sci->sc_seg_ctime = get_seconds();
2030 err = nilfs_segctor_collect(sci, nilfs, mode);
2034 /* Avoid empty segment */
2035 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2036 nilfs_segbuf_empty(sci->sc_curseg)) {
2037 nilfs_segctor_abort_construction(sci, nilfs, 1);
2041 err = nilfs_segctor_assign(sci, mode);
2045 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2046 nilfs_segctor_fill_in_file_bmap(sci);
2048 if (mode == SC_LSEG_SR &&
2049 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2050 err = nilfs_segctor_fill_in_checkpoint(sci);
2052 goto failed_to_write;
2054 nilfs_segctor_fill_in_super_root(sci, nilfs);
2056 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2058 /* Write partial segments */
2059 nilfs_segctor_prepare_write(sci);
2061 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2062 nilfs->ns_crc_seed);
2064 err = nilfs_segctor_write(sci, nilfs);
2066 goto failed_to_write;
2068 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2069 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2071 * At this point, we avoid double buffering
2072 * for blocksize < pagesize because page dirty
2073 * flag is turned off during write and dirty
2074 * buffers are not properly collected for
2075 * pages crossing over segments.
2077 err = nilfs_segctor_wait(sci);
2079 goto failed_to_write;
2081 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2084 nilfs_segctor_drop_written_files(sci, nilfs);
2088 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2089 nilfs_redirty_inodes(&sci->sc_dirty_files);
2092 if (nilfs_doing_gc())
2093 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2094 nilfs_segctor_abort_construction(sci, nilfs, err);
2099 * nilfs_segctor_start_timer - set timer of background write
2100 * @sci: nilfs_sc_info
2102 * If the timer has already been set, it ignores the new request.
2103 * This function MUST be called within a section locking the segment
2106 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2108 spin_lock(&sci->sc_state_lock);
2109 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2110 sci->sc_timer.expires = jiffies + sci->sc_interval;
2111 add_timer(&sci->sc_timer);
2112 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2114 spin_unlock(&sci->sc_state_lock);
2117 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2119 spin_lock(&sci->sc_state_lock);
2120 if (!(sci->sc_flush_request & (1 << bn))) {
2121 unsigned long prev_req = sci->sc_flush_request;
2123 sci->sc_flush_request |= (1 << bn);
2125 wake_up(&sci->sc_wait_daemon);
2127 spin_unlock(&sci->sc_state_lock);
2131 * nilfs_flush_segment - trigger a segment construction for resource control
2133 * @ino: inode number of the file to be flushed out.
2135 void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2137 struct the_nilfs *nilfs = sb->s_fs_info;
2138 struct nilfs_sc_info *sci = nilfs->ns_writer;
2140 if (!sci || nilfs_doing_construction())
2142 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2143 /* assign bit 0 to data files */
2146 struct nilfs_segctor_wait_request {
2153 static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2155 struct nilfs_segctor_wait_request wait_req;
2158 spin_lock(&sci->sc_state_lock);
2159 init_wait(&wait_req.wq);
2161 atomic_set(&wait_req.done, 0);
2162 wait_req.seq = ++sci->sc_seq_request;
2163 spin_unlock(&sci->sc_state_lock);
2165 init_waitqueue_entry(&wait_req.wq, current);
2166 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2167 set_current_state(TASK_INTERRUPTIBLE);
2168 wake_up(&sci->sc_wait_daemon);
2171 if (atomic_read(&wait_req.done)) {
2175 if (!signal_pending(current)) {
2182 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2186 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2188 struct nilfs_segctor_wait_request *wrq, *n;
2189 unsigned long flags;
2191 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2192 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2194 if (!atomic_read(&wrq->done) &&
2195 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2197 atomic_set(&wrq->done, 1);
2199 if (atomic_read(&wrq->done)) {
2200 wrq->wq.func(&wrq->wq,
2201 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2205 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2209 * nilfs_construct_segment - construct a logical segment
2212 * Return Value: On success, 0 is retured. On errors, one of the following
2213 * negative error code is returned.
2215 * %-EROFS - Read only filesystem.
2219 * %-ENOSPC - No space left on device (only in a panic state).
2221 * %-ERESTARTSYS - Interrupted.
2223 * %-ENOMEM - Insufficient memory available.
2225 int nilfs_construct_segment(struct super_block *sb)
2227 struct the_nilfs *nilfs = sb->s_fs_info;
2228 struct nilfs_sc_info *sci = nilfs->ns_writer;
2229 struct nilfs_transaction_info *ti;
2235 /* A call inside transactions causes a deadlock. */
2236 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2238 err = nilfs_segctor_sync(sci);
2243 * nilfs_construct_dsync_segment - construct a data-only logical segment
2245 * @inode: inode whose data blocks should be written out
2246 * @start: start byte offset
2247 * @end: end byte offset (inclusive)
2249 * Return Value: On success, 0 is retured. On errors, one of the following
2250 * negative error code is returned.
2252 * %-EROFS - Read only filesystem.
2256 * %-ENOSPC - No space left on device (only in a panic state).
2258 * %-ERESTARTSYS - Interrupted.
2260 * %-ENOMEM - Insufficient memory available.
2262 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2263 loff_t start, loff_t end)
2265 struct the_nilfs *nilfs = sb->s_fs_info;
2266 struct nilfs_sc_info *sci = nilfs->ns_writer;
2267 struct nilfs_inode_info *ii;
2268 struct nilfs_transaction_info ti;
2274 nilfs_transaction_lock(sb, &ti, 0);
2276 ii = NILFS_I(inode);
2277 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2278 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2279 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2280 nilfs_discontinued(nilfs)) {
2281 nilfs_transaction_unlock(sb);
2282 err = nilfs_segctor_sync(sci);
2286 spin_lock(&nilfs->ns_inode_lock);
2287 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2288 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2289 spin_unlock(&nilfs->ns_inode_lock);
2290 nilfs_transaction_unlock(sb);
2293 spin_unlock(&nilfs->ns_inode_lock);
2294 sci->sc_dsync_inode = ii;
2295 sci->sc_dsync_start = start;
2296 sci->sc_dsync_end = end;
2298 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2300 nilfs->ns_flushed_device = 0;
2302 nilfs_transaction_unlock(sb);
2306 #define FLUSH_FILE_BIT (0x1) /* data file only */
2307 #define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2310 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2311 * @sci: segment constructor object
2313 static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2315 spin_lock(&sci->sc_state_lock);
2316 sci->sc_seq_accepted = sci->sc_seq_request;
2317 spin_unlock(&sci->sc_state_lock);
2318 del_timer_sync(&sci->sc_timer);
2322 * nilfs_segctor_notify - notify the result of request to caller threads
2323 * @sci: segment constructor object
2324 * @mode: mode of log forming
2325 * @err: error code to be notified
2327 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2329 /* Clear requests (even when the construction failed) */
2330 spin_lock(&sci->sc_state_lock);
2332 if (mode == SC_LSEG_SR) {
2333 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2334 sci->sc_seq_done = sci->sc_seq_accepted;
2335 nilfs_segctor_wakeup(sci, err);
2336 sci->sc_flush_request = 0;
2338 if (mode == SC_FLUSH_FILE)
2339 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2340 else if (mode == SC_FLUSH_DAT)
2341 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2343 /* re-enable timer if checkpoint creation was not done */
2344 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2345 time_before(jiffies, sci->sc_timer.expires))
2346 add_timer(&sci->sc_timer);
2348 spin_unlock(&sci->sc_state_lock);
2352 * nilfs_segctor_construct - form logs and write them to disk
2353 * @sci: segment constructor object
2354 * @mode: mode of log forming
2356 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2358 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2359 struct nilfs_super_block **sbp;
2362 nilfs_segctor_accept(sci);
2364 if (nilfs_discontinued(nilfs))
2366 if (!nilfs_segctor_confirm(sci))
2367 err = nilfs_segctor_do_construct(sci, mode);
2370 if (mode != SC_FLUSH_DAT)
2371 atomic_set(&nilfs->ns_ndirtyblks, 0);
2372 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2373 nilfs_discontinued(nilfs)) {
2374 down_write(&nilfs->ns_sem);
2376 sbp = nilfs_prepare_super(sci->sc_super,
2377 nilfs_sb_will_flip(nilfs));
2379 nilfs_set_log_cursor(sbp[0], nilfs);
2380 err = nilfs_commit_super(sci->sc_super,
2383 up_write(&nilfs->ns_sem);
2387 nilfs_segctor_notify(sci, mode, err);
2391 static void nilfs_construction_timeout(unsigned long data)
2393 struct task_struct *p = (struct task_struct *)data;
2399 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2401 struct nilfs_inode_info *ii, *n;
2403 list_for_each_entry_safe(ii, n, head, i_dirty) {
2404 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2406 list_del_init(&ii->i_dirty);
2407 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2408 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2409 iput(&ii->vfs_inode);
2413 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2416 struct the_nilfs *nilfs = sb->s_fs_info;
2417 struct nilfs_sc_info *sci = nilfs->ns_writer;
2418 struct nilfs_transaction_info ti;
2424 nilfs_transaction_lock(sb, &ti, 1);
2426 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2430 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2431 if (unlikely(err)) {
2432 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2436 sci->sc_freesegs = kbufs[4];
2437 sci->sc_nfreesegs = argv[4].v_nmembs;
2438 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2441 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2442 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2447 nilfs_warning(sb, __func__,
2448 "segment construction failed. (err=%d)", err);
2449 set_current_state(TASK_INTERRUPTIBLE);
2450 schedule_timeout(sci->sc_interval);
2452 if (nilfs_test_opt(nilfs, DISCARD)) {
2453 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2457 "NILFS warning: error %d on discard request, "
2458 "turning discards off for the device\n", ret);
2459 nilfs_clear_opt(nilfs, DISCARD);
2464 sci->sc_freesegs = NULL;
2465 sci->sc_nfreesegs = 0;
2466 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2467 nilfs_transaction_unlock(sb);
2471 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2473 struct nilfs_transaction_info ti;
2475 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2476 nilfs_segctor_construct(sci, mode);
2479 * Unclosed segment should be retried. We do this using sc_timer.
2480 * Timeout of sc_timer will invoke complete construction which leads
2481 * to close the current logical segment.
2483 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2484 nilfs_segctor_start_timer(sci);
2486 nilfs_transaction_unlock(sci->sc_super);
2489 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2493 spin_lock(&sci->sc_state_lock);
2494 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2495 SC_FLUSH_DAT : SC_FLUSH_FILE;
2496 spin_unlock(&sci->sc_state_lock);
2499 nilfs_segctor_do_construct(sci, mode);
2501 spin_lock(&sci->sc_state_lock);
2502 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2503 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2504 spin_unlock(&sci->sc_state_lock);
2506 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2509 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2511 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2512 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2513 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2514 return SC_FLUSH_FILE;
2515 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2516 return SC_FLUSH_DAT;
2522 * nilfs_segctor_thread - main loop of the segment constructor thread.
2523 * @arg: pointer to a struct nilfs_sc_info.
2525 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2526 * to execute segment constructions.
2528 static int nilfs_segctor_thread(void *arg)
2530 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2531 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2534 sci->sc_timer.data = (unsigned long)current;
2535 sci->sc_timer.function = nilfs_construction_timeout;
2538 sci->sc_task = current;
2539 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2541 "segctord starting. Construction interval = %lu seconds, "
2542 "CP frequency < %lu seconds\n",
2543 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2545 spin_lock(&sci->sc_state_lock);
2550 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2553 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2555 else if (!sci->sc_flush_request)
2558 mode = nilfs_segctor_flush_mode(sci);
2560 spin_unlock(&sci->sc_state_lock);
2561 nilfs_segctor_thread_construct(sci, mode);
2562 spin_lock(&sci->sc_state_lock);
2567 if (freezing(current)) {
2568 spin_unlock(&sci->sc_state_lock);
2570 spin_lock(&sci->sc_state_lock);
2573 int should_sleep = 1;
2575 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2576 TASK_INTERRUPTIBLE);
2578 if (sci->sc_seq_request != sci->sc_seq_done)
2580 else if (sci->sc_flush_request)
2582 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2583 should_sleep = time_before(jiffies,
2584 sci->sc_timer.expires);
2587 spin_unlock(&sci->sc_state_lock);
2589 spin_lock(&sci->sc_state_lock);
2591 finish_wait(&sci->sc_wait_daemon, &wait);
2592 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2593 time_after_eq(jiffies, sci->sc_timer.expires));
2595 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2596 set_nilfs_discontinued(nilfs);
2601 spin_unlock(&sci->sc_state_lock);
2604 sci->sc_task = NULL;
2605 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2609 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2611 struct task_struct *t;
2613 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2615 int err = PTR_ERR(t);
2617 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2621 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2625 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2626 __acquires(&sci->sc_state_lock)
2627 __releases(&sci->sc_state_lock)
2629 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2631 while (sci->sc_task) {
2632 wake_up(&sci->sc_wait_daemon);
2633 spin_unlock(&sci->sc_state_lock);
2634 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2635 spin_lock(&sci->sc_state_lock);
2640 * Setup & clean-up functions
2642 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2643 struct nilfs_root *root)
2645 struct the_nilfs *nilfs = sb->s_fs_info;
2646 struct nilfs_sc_info *sci;
2648 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2654 nilfs_get_root(root);
2655 sci->sc_root = root;
2657 init_waitqueue_head(&sci->sc_wait_request);
2658 init_waitqueue_head(&sci->sc_wait_daemon);
2659 init_waitqueue_head(&sci->sc_wait_task);
2660 spin_lock_init(&sci->sc_state_lock);
2661 INIT_LIST_HEAD(&sci->sc_dirty_files);
2662 INIT_LIST_HEAD(&sci->sc_segbufs);
2663 INIT_LIST_HEAD(&sci->sc_write_logs);
2664 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2665 INIT_LIST_HEAD(&sci->sc_iput_queue);
2666 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2667 init_timer(&sci->sc_timer);
2669 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2670 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2671 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2673 if (nilfs->ns_interval)
2674 sci->sc_interval = HZ * nilfs->ns_interval;
2675 if (nilfs->ns_watermark)
2676 sci->sc_watermark = nilfs->ns_watermark;
2680 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2682 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2684 /* The segctord thread was stopped and its timer was removed.
2685 But some tasks remain. */
2687 struct nilfs_transaction_info ti;
2689 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2690 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2691 nilfs_transaction_unlock(sci->sc_super);
2693 flush_work(&sci->sc_iput_work);
2695 } while (ret && retrycount-- > 0);
2699 * nilfs_segctor_destroy - destroy the segment constructor.
2700 * @sci: nilfs_sc_info
2702 * nilfs_segctor_destroy() kills the segctord thread and frees
2703 * the nilfs_sc_info struct.
2704 * Caller must hold the segment semaphore.
2706 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2708 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2711 up_write(&nilfs->ns_segctor_sem);
2713 spin_lock(&sci->sc_state_lock);
2714 nilfs_segctor_kill_thread(sci);
2715 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2716 || sci->sc_seq_request != sci->sc_seq_done);
2717 spin_unlock(&sci->sc_state_lock);
2719 if (flush_work(&sci->sc_iput_work))
2722 if (flag || !nilfs_segctor_confirm(sci))
2723 nilfs_segctor_write_out(sci);
2725 if (!list_empty(&sci->sc_dirty_files)) {
2726 nilfs_warning(sci->sc_super, __func__,
2727 "dirty file(s) after the final construction");
2728 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2731 if (!list_empty(&sci->sc_iput_queue)) {
2732 nilfs_warning(sci->sc_super, __func__,
2733 "iput queue is not empty");
2734 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2737 WARN_ON(!list_empty(&sci->sc_segbufs));
2738 WARN_ON(!list_empty(&sci->sc_write_logs));
2740 nilfs_put_root(sci->sc_root);
2742 down_write(&nilfs->ns_segctor_sem);
2744 del_timer_sync(&sci->sc_timer);
2749 * nilfs_attach_log_writer - attach log writer
2750 * @sb: super block instance
2751 * @root: root object of the current filesystem tree
2753 * This allocates a log writer object, initializes it, and starts the
2756 * Return Value: On success, 0 is returned. On error, one of the following
2757 * negative error code is returned.
2759 * %-ENOMEM - Insufficient memory available.
2761 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2763 struct the_nilfs *nilfs = sb->s_fs_info;
2766 if (nilfs->ns_writer) {
2768 * This happens if the filesystem was remounted
2769 * read/write after nilfs_error degenerated it into a
2772 nilfs_detach_log_writer(sb);
2775 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2776 if (!nilfs->ns_writer)
2779 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2781 kfree(nilfs->ns_writer);
2782 nilfs->ns_writer = NULL;
2788 * nilfs_detach_log_writer - destroy log writer
2789 * @sb: super block instance
2791 * This kills log writer daemon, frees the log writer object, and
2792 * destroys list of dirty files.
2794 void nilfs_detach_log_writer(struct super_block *sb)
2796 struct the_nilfs *nilfs = sb->s_fs_info;
2797 LIST_HEAD(garbage_list);
2799 down_write(&nilfs->ns_segctor_sem);
2800 if (nilfs->ns_writer) {
2801 nilfs_segctor_destroy(nilfs->ns_writer);
2802 nilfs->ns_writer = NULL;
2805 /* Force to free the list of dirty files */
2806 spin_lock(&nilfs->ns_inode_lock);
2807 if (!list_empty(&nilfs->ns_dirty_files)) {
2808 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2809 nilfs_warning(sb, __func__,
2810 "Hit dirty file after stopped log writer");
2812 spin_unlock(&nilfs->ns_inode_lock);
2813 up_write(&nilfs->ns_segctor_sem);
2815 nilfs_dispose_list(nilfs, &garbage_list, 1);