staging: rtl8723bs: os_dep: change return type of rtw_suspend_ap_wow
[linux/fpc-iii.git] / fs / nilfs2 / segment.c
blob445eef41bfaf00a948b5c29f3041703bba369dfa
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * segment.c - NILFS segment constructor.
5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
7 * Written by Ryusuke Konishi.
9 */
11 #include <linux/pagemap.h>
12 #include <linux/buffer_head.h>
13 #include <linux/writeback.h>
14 #include <linux/bitops.h>
15 #include <linux/bio.h>
16 #include <linux/completion.h>
17 #include <linux/blkdev.h>
18 #include <linux/backing-dev.h>
19 #include <linux/freezer.h>
20 #include <linux/kthread.h>
21 #include <linux/crc32.h>
22 #include <linux/pagevec.h>
23 #include <linux/slab.h>
24 #include <linux/sched/signal.h>
26 #include "nilfs.h"
27 #include "btnode.h"
28 #include "page.h"
29 #include "segment.h"
30 #include "sufile.h"
31 #include "cpfile.h"
32 #include "ifile.h"
33 #include "segbuf.h"
37 * Segment constructor
39 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
41 #define SC_MAX_SEGDELTA 64 /*
42 * Upper limit of the number of segments
43 * appended in collection retry loop
46 /* Construction mode */
47 enum {
48 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
49 SC_LSEG_DSYNC, /*
50 * Flush data blocks of a given file and make
51 * a logical segment without a super root.
53 SC_FLUSH_FILE, /*
54 * Flush data files, leads to segment writes without
55 * creating a checkpoint.
57 SC_FLUSH_DAT, /*
58 * Flush DAT file. This also creates segments
59 * without a checkpoint.
63 /* Stage numbers of dirty block collection */
64 enum {
65 NILFS_ST_INIT = 0,
66 NILFS_ST_GC, /* Collecting dirty blocks for GC */
67 NILFS_ST_FILE,
68 NILFS_ST_IFILE,
69 NILFS_ST_CPFILE,
70 NILFS_ST_SUFILE,
71 NILFS_ST_DAT,
72 NILFS_ST_SR, /* Super root */
73 NILFS_ST_DSYNC, /* Data sync blocks */
74 NILFS_ST_DONE,
77 #define CREATE_TRACE_POINTS
78 #include <trace/events/nilfs2.h>
81 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
82 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
83 * the variable must use them because transition of stage count must involve
84 * trace events (trace_nilfs2_collection_stage_transition).
86 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
87 * produce tracepoint events. It is provided just for making the intention
88 * clear.
90 static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
92 sci->sc_stage.scnt++;
93 trace_nilfs2_collection_stage_transition(sci);
96 static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
98 sci->sc_stage.scnt = next_scnt;
99 trace_nilfs2_collection_stage_transition(sci);
102 static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
104 return sci->sc_stage.scnt;
107 /* State flags of collection */
108 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
109 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
110 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
111 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
113 /* Operations depending on the construction mode and file type */
114 struct nilfs_sc_operations {
115 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
116 struct inode *);
117 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
118 struct inode *);
119 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
120 struct inode *);
121 void (*write_data_binfo)(struct nilfs_sc_info *,
122 struct nilfs_segsum_pointer *,
123 union nilfs_binfo *);
124 void (*write_node_binfo)(struct nilfs_sc_info *,
125 struct nilfs_segsum_pointer *,
126 union nilfs_binfo *);
130 * Other definitions
132 static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
133 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
134 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
135 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
137 #define nilfs_cnt32_gt(a, b) \
138 (typecheck(__u32, a) && typecheck(__u32, b) && \
139 ((__s32)(b) - (__s32)(a) < 0))
140 #define nilfs_cnt32_ge(a, b) \
141 (typecheck(__u32, a) && typecheck(__u32, b) && \
142 ((__s32)(a) - (__s32)(b) >= 0))
143 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
144 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
146 static int nilfs_prepare_segment_lock(struct super_block *sb,
147 struct nilfs_transaction_info *ti)
149 struct nilfs_transaction_info *cur_ti = current->journal_info;
150 void *save = NULL;
152 if (cur_ti) {
153 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
154 return ++cur_ti->ti_count;
157 * If journal_info field is occupied by other FS,
158 * it is saved and will be restored on
159 * nilfs_transaction_commit().
161 nilfs_msg(sb, KERN_WARNING, "journal info from a different FS");
162 save = current->journal_info;
164 if (!ti) {
165 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
166 if (!ti)
167 return -ENOMEM;
168 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
169 } else {
170 ti->ti_flags = 0;
172 ti->ti_count = 0;
173 ti->ti_save = save;
174 ti->ti_magic = NILFS_TI_MAGIC;
175 current->journal_info = ti;
176 return 0;
180 * nilfs_transaction_begin - start indivisible file operations.
181 * @sb: super block
182 * @ti: nilfs_transaction_info
183 * @vacancy_check: flags for vacancy rate checks
185 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
186 * the segment semaphore, to make a segment construction and write tasks
187 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
188 * The region enclosed by these two functions can be nested. To avoid a
189 * deadlock, the semaphore is only acquired or released in the outermost call.
191 * This function allocates a nilfs_transaction_info struct to keep context
192 * information on it. It is initialized and hooked onto the current task in
193 * the outermost call. If a pre-allocated struct is given to @ti, it is used
194 * instead; otherwise a new struct is assigned from a slab.
196 * When @vacancy_check flag is set, this function will check the amount of
197 * free space, and will wait for the GC to reclaim disk space if low capacity.
199 * Return Value: On success, 0 is returned. On error, one of the following
200 * negative error code is returned.
202 * %-ENOMEM - Insufficient memory available.
204 * %-ENOSPC - No space left on device
206 int nilfs_transaction_begin(struct super_block *sb,
207 struct nilfs_transaction_info *ti,
208 int vacancy_check)
210 struct the_nilfs *nilfs;
211 int ret = nilfs_prepare_segment_lock(sb, ti);
212 struct nilfs_transaction_info *trace_ti;
214 if (unlikely(ret < 0))
215 return ret;
216 if (ret > 0) {
217 trace_ti = current->journal_info;
219 trace_nilfs2_transaction_transition(sb, trace_ti,
220 trace_ti->ti_count, trace_ti->ti_flags,
221 TRACE_NILFS2_TRANSACTION_BEGIN);
222 return 0;
225 sb_start_intwrite(sb);
227 nilfs = sb->s_fs_info;
228 down_read(&nilfs->ns_segctor_sem);
229 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
230 up_read(&nilfs->ns_segctor_sem);
231 ret = -ENOSPC;
232 goto failed;
235 trace_ti = current->journal_info;
236 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
237 trace_ti->ti_flags,
238 TRACE_NILFS2_TRANSACTION_BEGIN);
239 return 0;
241 failed:
242 ti = current->journal_info;
243 current->journal_info = ti->ti_save;
244 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
245 kmem_cache_free(nilfs_transaction_cachep, ti);
246 sb_end_intwrite(sb);
247 return ret;
251 * nilfs_transaction_commit - commit indivisible file operations.
252 * @sb: super block
254 * nilfs_transaction_commit() releases the read semaphore which is
255 * acquired by nilfs_transaction_begin(). This is only performed
256 * in outermost call of this function. If a commit flag is set,
257 * nilfs_transaction_commit() sets a timer to start the segment
258 * constructor. If a sync flag is set, it starts construction
259 * directly.
261 int nilfs_transaction_commit(struct super_block *sb)
263 struct nilfs_transaction_info *ti = current->journal_info;
264 struct the_nilfs *nilfs = sb->s_fs_info;
265 int err = 0;
267 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
268 ti->ti_flags |= NILFS_TI_COMMIT;
269 if (ti->ti_count > 0) {
270 ti->ti_count--;
271 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
272 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
273 return 0;
275 if (nilfs->ns_writer) {
276 struct nilfs_sc_info *sci = nilfs->ns_writer;
278 if (ti->ti_flags & NILFS_TI_COMMIT)
279 nilfs_segctor_start_timer(sci);
280 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
281 nilfs_segctor_do_flush(sci, 0);
283 up_read(&nilfs->ns_segctor_sem);
284 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
285 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
287 current->journal_info = ti->ti_save;
289 if (ti->ti_flags & NILFS_TI_SYNC)
290 err = nilfs_construct_segment(sb);
291 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
292 kmem_cache_free(nilfs_transaction_cachep, ti);
293 sb_end_intwrite(sb);
294 return err;
297 void nilfs_transaction_abort(struct super_block *sb)
299 struct nilfs_transaction_info *ti = current->journal_info;
300 struct the_nilfs *nilfs = sb->s_fs_info;
302 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
303 if (ti->ti_count > 0) {
304 ti->ti_count--;
305 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
306 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
307 return;
309 up_read(&nilfs->ns_segctor_sem);
311 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
312 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
314 current->journal_info = ti->ti_save;
315 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
316 kmem_cache_free(nilfs_transaction_cachep, ti);
317 sb_end_intwrite(sb);
320 void nilfs_relax_pressure_in_lock(struct super_block *sb)
322 struct the_nilfs *nilfs = sb->s_fs_info;
323 struct nilfs_sc_info *sci = nilfs->ns_writer;
325 if (!sci || !sci->sc_flush_request)
326 return;
328 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
329 up_read(&nilfs->ns_segctor_sem);
331 down_write(&nilfs->ns_segctor_sem);
332 if (sci->sc_flush_request &&
333 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
334 struct nilfs_transaction_info *ti = current->journal_info;
336 ti->ti_flags |= NILFS_TI_WRITER;
337 nilfs_segctor_do_immediate_flush(sci);
338 ti->ti_flags &= ~NILFS_TI_WRITER;
340 downgrade_write(&nilfs->ns_segctor_sem);
343 static void nilfs_transaction_lock(struct super_block *sb,
344 struct nilfs_transaction_info *ti,
345 int gcflag)
347 struct nilfs_transaction_info *cur_ti = current->journal_info;
348 struct the_nilfs *nilfs = sb->s_fs_info;
349 struct nilfs_sc_info *sci = nilfs->ns_writer;
351 WARN_ON(cur_ti);
352 ti->ti_flags = NILFS_TI_WRITER;
353 ti->ti_count = 0;
354 ti->ti_save = cur_ti;
355 ti->ti_magic = NILFS_TI_MAGIC;
356 current->journal_info = ti;
358 for (;;) {
359 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
360 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
362 down_write(&nilfs->ns_segctor_sem);
363 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
364 break;
366 nilfs_segctor_do_immediate_flush(sci);
368 up_write(&nilfs->ns_segctor_sem);
369 cond_resched();
371 if (gcflag)
372 ti->ti_flags |= NILFS_TI_GC;
374 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
375 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
378 static void nilfs_transaction_unlock(struct super_block *sb)
380 struct nilfs_transaction_info *ti = current->journal_info;
381 struct the_nilfs *nilfs = sb->s_fs_info;
383 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
384 BUG_ON(ti->ti_count > 0);
386 up_write(&nilfs->ns_segctor_sem);
387 current->journal_info = ti->ti_save;
389 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
390 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
393 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
394 struct nilfs_segsum_pointer *ssp,
395 unsigned int bytes)
397 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
398 unsigned int blocksize = sci->sc_super->s_blocksize;
399 void *p;
401 if (unlikely(ssp->offset + bytes > blocksize)) {
402 ssp->offset = 0;
403 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
404 &segbuf->sb_segsum_buffers));
405 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
407 p = ssp->bh->b_data + ssp->offset;
408 ssp->offset += bytes;
409 return p;
413 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
414 * @sci: nilfs_sc_info
416 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
418 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
419 struct buffer_head *sumbh;
420 unsigned int sumbytes;
421 unsigned int flags = 0;
422 int err;
424 if (nilfs_doing_gc())
425 flags = NILFS_SS_GC;
426 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
427 if (unlikely(err))
428 return err;
430 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
431 sumbytes = segbuf->sb_sum.sumbytes;
432 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
433 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
434 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
435 return 0;
438 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
440 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
441 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
442 return -E2BIG; /*
443 * The current segment is filled up
444 * (internal code)
446 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
447 return nilfs_segctor_reset_segment_buffer(sci);
450 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
452 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
453 int err;
455 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
456 err = nilfs_segctor_feed_segment(sci);
457 if (err)
458 return err;
459 segbuf = sci->sc_curseg;
461 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
462 if (likely(!err))
463 segbuf->sb_sum.flags |= NILFS_SS_SR;
464 return err;
468 * Functions for making segment summary and payloads
470 static int nilfs_segctor_segsum_block_required(
471 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
472 unsigned int binfo_size)
474 unsigned int blocksize = sci->sc_super->s_blocksize;
475 /* Size of finfo and binfo is enough small against blocksize */
477 return ssp->offset + binfo_size +
478 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
479 blocksize;
482 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
483 struct inode *inode)
485 sci->sc_curseg->sb_sum.nfinfo++;
486 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
487 nilfs_segctor_map_segsum_entry(
488 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
490 if (NILFS_I(inode)->i_root &&
491 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
492 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
493 /* skip finfo */
496 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
497 struct inode *inode)
499 struct nilfs_finfo *finfo;
500 struct nilfs_inode_info *ii;
501 struct nilfs_segment_buffer *segbuf;
502 __u64 cno;
504 if (sci->sc_blk_cnt == 0)
505 return;
507 ii = NILFS_I(inode);
509 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
510 cno = ii->i_cno;
511 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
512 cno = 0;
513 else
514 cno = sci->sc_cno;
516 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
517 sizeof(*finfo));
518 finfo->fi_ino = cpu_to_le64(inode->i_ino);
519 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
520 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
521 finfo->fi_cno = cpu_to_le64(cno);
523 segbuf = sci->sc_curseg;
524 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
525 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
526 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
527 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
530 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
531 struct buffer_head *bh,
532 struct inode *inode,
533 unsigned int binfo_size)
535 struct nilfs_segment_buffer *segbuf;
536 int required, err = 0;
538 retry:
539 segbuf = sci->sc_curseg;
540 required = nilfs_segctor_segsum_block_required(
541 sci, &sci->sc_binfo_ptr, binfo_size);
542 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
543 nilfs_segctor_end_finfo(sci, inode);
544 err = nilfs_segctor_feed_segment(sci);
545 if (err)
546 return err;
547 goto retry;
549 if (unlikely(required)) {
550 err = nilfs_segbuf_extend_segsum(segbuf);
551 if (unlikely(err))
552 goto failed;
554 if (sci->sc_blk_cnt == 0)
555 nilfs_segctor_begin_finfo(sci, inode);
557 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
558 /* Substitution to vblocknr is delayed until update_blocknr() */
559 nilfs_segbuf_add_file_buffer(segbuf, bh);
560 sci->sc_blk_cnt++;
561 failed:
562 return err;
566 * Callback functions that enumerate, mark, and collect dirty blocks
568 static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
569 struct buffer_head *bh, struct inode *inode)
571 int err;
573 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
574 if (err < 0)
575 return err;
577 err = nilfs_segctor_add_file_block(sci, bh, inode,
578 sizeof(struct nilfs_binfo_v));
579 if (!err)
580 sci->sc_datablk_cnt++;
581 return err;
584 static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
585 struct buffer_head *bh,
586 struct inode *inode)
588 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
591 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
592 struct buffer_head *bh,
593 struct inode *inode)
595 WARN_ON(!buffer_dirty(bh));
596 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
599 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
600 struct nilfs_segsum_pointer *ssp,
601 union nilfs_binfo *binfo)
603 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
604 sci, ssp, sizeof(*binfo_v));
605 *binfo_v = binfo->bi_v;
608 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
609 struct nilfs_segsum_pointer *ssp,
610 union nilfs_binfo *binfo)
612 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
613 sci, ssp, sizeof(*vblocknr));
614 *vblocknr = binfo->bi_v.bi_vblocknr;
617 static const struct nilfs_sc_operations nilfs_sc_file_ops = {
618 .collect_data = nilfs_collect_file_data,
619 .collect_node = nilfs_collect_file_node,
620 .collect_bmap = nilfs_collect_file_bmap,
621 .write_data_binfo = nilfs_write_file_data_binfo,
622 .write_node_binfo = nilfs_write_file_node_binfo,
625 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
626 struct buffer_head *bh, struct inode *inode)
628 int err;
630 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
631 if (err < 0)
632 return err;
634 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
635 if (!err)
636 sci->sc_datablk_cnt++;
637 return err;
640 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
641 struct buffer_head *bh, struct inode *inode)
643 WARN_ON(!buffer_dirty(bh));
644 return nilfs_segctor_add_file_block(sci, bh, inode,
645 sizeof(struct nilfs_binfo_dat));
648 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
649 struct nilfs_segsum_pointer *ssp,
650 union nilfs_binfo *binfo)
652 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
653 sizeof(*blkoff));
654 *blkoff = binfo->bi_dat.bi_blkoff;
657 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
658 struct nilfs_segsum_pointer *ssp,
659 union nilfs_binfo *binfo)
661 struct nilfs_binfo_dat *binfo_dat =
662 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
663 *binfo_dat = binfo->bi_dat;
666 static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
667 .collect_data = nilfs_collect_dat_data,
668 .collect_node = nilfs_collect_file_node,
669 .collect_bmap = nilfs_collect_dat_bmap,
670 .write_data_binfo = nilfs_write_dat_data_binfo,
671 .write_node_binfo = nilfs_write_dat_node_binfo,
674 static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
675 .collect_data = nilfs_collect_file_data,
676 .collect_node = NULL,
677 .collect_bmap = NULL,
678 .write_data_binfo = nilfs_write_file_data_binfo,
679 .write_node_binfo = NULL,
682 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
683 struct list_head *listp,
684 size_t nlimit,
685 loff_t start, loff_t end)
687 struct address_space *mapping = inode->i_mapping;
688 struct pagevec pvec;
689 pgoff_t index = 0, last = ULONG_MAX;
690 size_t ndirties = 0;
691 int i;
693 if (unlikely(start != 0 || end != LLONG_MAX)) {
695 * A valid range is given for sync-ing data pages. The
696 * range is rounded to per-page; extra dirty buffers
697 * may be included if blocksize < pagesize.
699 index = start >> PAGE_SHIFT;
700 last = end >> PAGE_SHIFT;
702 pagevec_init(&pvec);
703 repeat:
704 if (unlikely(index > last) ||
705 !pagevec_lookup_range_tag(&pvec, mapping, &index, last,
706 PAGECACHE_TAG_DIRTY))
707 return ndirties;
709 for (i = 0; i < pagevec_count(&pvec); i++) {
710 struct buffer_head *bh, *head;
711 struct page *page = pvec.pages[i];
713 lock_page(page);
714 if (!page_has_buffers(page))
715 create_empty_buffers(page, i_blocksize(inode), 0);
716 unlock_page(page);
718 bh = head = page_buffers(page);
719 do {
720 if (!buffer_dirty(bh) || buffer_async_write(bh))
721 continue;
722 get_bh(bh);
723 list_add_tail(&bh->b_assoc_buffers, listp);
724 ndirties++;
725 if (unlikely(ndirties >= nlimit)) {
726 pagevec_release(&pvec);
727 cond_resched();
728 return ndirties;
730 } while (bh = bh->b_this_page, bh != head);
732 pagevec_release(&pvec);
733 cond_resched();
734 goto repeat;
737 static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
738 struct list_head *listp)
740 struct nilfs_inode_info *ii = NILFS_I(inode);
741 struct address_space *mapping = &ii->i_btnode_cache;
742 struct pagevec pvec;
743 struct buffer_head *bh, *head;
744 unsigned int i;
745 pgoff_t index = 0;
747 pagevec_init(&pvec);
749 while (pagevec_lookup_tag(&pvec, mapping, &index,
750 PAGECACHE_TAG_DIRTY)) {
751 for (i = 0; i < pagevec_count(&pvec); i++) {
752 bh = head = page_buffers(pvec.pages[i]);
753 do {
754 if (buffer_dirty(bh) &&
755 !buffer_async_write(bh)) {
756 get_bh(bh);
757 list_add_tail(&bh->b_assoc_buffers,
758 listp);
760 bh = bh->b_this_page;
761 } while (bh != head);
763 pagevec_release(&pvec);
764 cond_resched();
768 static void nilfs_dispose_list(struct the_nilfs *nilfs,
769 struct list_head *head, int force)
771 struct nilfs_inode_info *ii, *n;
772 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
773 unsigned int nv = 0;
775 while (!list_empty(head)) {
776 spin_lock(&nilfs->ns_inode_lock);
777 list_for_each_entry_safe(ii, n, head, i_dirty) {
778 list_del_init(&ii->i_dirty);
779 if (force) {
780 if (unlikely(ii->i_bh)) {
781 brelse(ii->i_bh);
782 ii->i_bh = NULL;
784 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
785 set_bit(NILFS_I_QUEUED, &ii->i_state);
786 list_add_tail(&ii->i_dirty,
787 &nilfs->ns_dirty_files);
788 continue;
790 ivec[nv++] = ii;
791 if (nv == SC_N_INODEVEC)
792 break;
794 spin_unlock(&nilfs->ns_inode_lock);
796 for (pii = ivec; nv > 0; pii++, nv--)
797 iput(&(*pii)->vfs_inode);
801 static void nilfs_iput_work_func(struct work_struct *work)
803 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
804 sc_iput_work);
805 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
807 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
810 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
811 struct nilfs_root *root)
813 int ret = 0;
815 if (nilfs_mdt_fetch_dirty(root->ifile))
816 ret++;
817 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
818 ret++;
819 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
820 ret++;
821 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
822 ret++;
823 return ret;
826 static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
828 return list_empty(&sci->sc_dirty_files) &&
829 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
830 sci->sc_nfreesegs == 0 &&
831 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
834 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
836 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
837 int ret = 0;
839 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
840 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
842 spin_lock(&nilfs->ns_inode_lock);
843 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
844 ret++;
846 spin_unlock(&nilfs->ns_inode_lock);
847 return ret;
850 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
852 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
854 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
855 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
856 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
857 nilfs_mdt_clear_dirty(nilfs->ns_dat);
860 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
862 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
863 struct buffer_head *bh_cp;
864 struct nilfs_checkpoint *raw_cp;
865 int err;
867 /* XXX: this interface will be changed */
868 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
869 &raw_cp, &bh_cp);
870 if (likely(!err)) {
872 * The following code is duplicated with cpfile. But, it is
873 * needed to collect the checkpoint even if it was not newly
874 * created.
876 mark_buffer_dirty(bh_cp);
877 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
878 nilfs_cpfile_put_checkpoint(
879 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
880 } else
881 WARN_ON(err == -EINVAL || err == -ENOENT);
883 return err;
886 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
888 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
889 struct buffer_head *bh_cp;
890 struct nilfs_checkpoint *raw_cp;
891 int err;
893 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
894 &raw_cp, &bh_cp);
895 if (unlikely(err)) {
896 WARN_ON(err == -EINVAL || err == -ENOENT);
897 goto failed_ibh;
899 raw_cp->cp_snapshot_list.ssl_next = 0;
900 raw_cp->cp_snapshot_list.ssl_prev = 0;
901 raw_cp->cp_inodes_count =
902 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
903 raw_cp->cp_blocks_count =
904 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
905 raw_cp->cp_nblk_inc =
906 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
907 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
908 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
910 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
911 nilfs_checkpoint_clear_minor(raw_cp);
912 else
913 nilfs_checkpoint_set_minor(raw_cp);
915 nilfs_write_inode_common(sci->sc_root->ifile,
916 &raw_cp->cp_ifile_inode, 1);
917 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
918 return 0;
920 failed_ibh:
921 return err;
924 static void nilfs_fill_in_file_bmap(struct inode *ifile,
925 struct nilfs_inode_info *ii)
928 struct buffer_head *ibh;
929 struct nilfs_inode *raw_inode;
931 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
932 ibh = ii->i_bh;
933 BUG_ON(!ibh);
934 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
935 ibh);
936 nilfs_bmap_write(ii->i_bmap, raw_inode);
937 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
941 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
943 struct nilfs_inode_info *ii;
945 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
946 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
947 set_bit(NILFS_I_COLLECTED, &ii->i_state);
951 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
952 struct the_nilfs *nilfs)
954 struct buffer_head *bh_sr;
955 struct nilfs_super_root *raw_sr;
956 unsigned int isz, srsz;
958 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
959 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
960 isz = nilfs->ns_inode_size;
961 srsz = NILFS_SR_BYTES(isz);
963 raw_sr->sr_bytes = cpu_to_le16(srsz);
964 raw_sr->sr_nongc_ctime
965 = cpu_to_le64(nilfs_doing_gc() ?
966 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
967 raw_sr->sr_flags = 0;
969 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
970 NILFS_SR_DAT_OFFSET(isz), 1);
971 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
972 NILFS_SR_CPFILE_OFFSET(isz), 1);
973 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
974 NILFS_SR_SUFILE_OFFSET(isz), 1);
975 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
978 static void nilfs_redirty_inodes(struct list_head *head)
980 struct nilfs_inode_info *ii;
982 list_for_each_entry(ii, head, i_dirty) {
983 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
984 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
988 static void nilfs_drop_collected_inodes(struct list_head *head)
990 struct nilfs_inode_info *ii;
992 list_for_each_entry(ii, head, i_dirty) {
993 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
994 continue;
996 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
997 set_bit(NILFS_I_UPDATED, &ii->i_state);
1001 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1002 struct inode *inode,
1003 struct list_head *listp,
1004 int (*collect)(struct nilfs_sc_info *,
1005 struct buffer_head *,
1006 struct inode *))
1008 struct buffer_head *bh, *n;
1009 int err = 0;
1011 if (collect) {
1012 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1013 list_del_init(&bh->b_assoc_buffers);
1014 err = collect(sci, bh, inode);
1015 brelse(bh);
1016 if (unlikely(err))
1017 goto dispose_buffers;
1019 return 0;
1022 dispose_buffers:
1023 while (!list_empty(listp)) {
1024 bh = list_first_entry(listp, struct buffer_head,
1025 b_assoc_buffers);
1026 list_del_init(&bh->b_assoc_buffers);
1027 brelse(bh);
1029 return err;
1032 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1034 /* Remaining number of blocks within segment buffer */
1035 return sci->sc_segbuf_nblocks -
1036 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1039 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1040 struct inode *inode,
1041 const struct nilfs_sc_operations *sc_ops)
1043 LIST_HEAD(data_buffers);
1044 LIST_HEAD(node_buffers);
1045 int err;
1047 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1048 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1050 n = nilfs_lookup_dirty_data_buffers(
1051 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1052 if (n > rest) {
1053 err = nilfs_segctor_apply_buffers(
1054 sci, inode, &data_buffers,
1055 sc_ops->collect_data);
1056 BUG_ON(!err); /* always receive -E2BIG or true error */
1057 goto break_or_fail;
1060 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1062 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1063 err = nilfs_segctor_apply_buffers(
1064 sci, inode, &data_buffers, sc_ops->collect_data);
1065 if (unlikely(err)) {
1066 /* dispose node list */
1067 nilfs_segctor_apply_buffers(
1068 sci, inode, &node_buffers, NULL);
1069 goto break_or_fail;
1071 sci->sc_stage.flags |= NILFS_CF_NODE;
1073 /* Collect node */
1074 err = nilfs_segctor_apply_buffers(
1075 sci, inode, &node_buffers, sc_ops->collect_node);
1076 if (unlikely(err))
1077 goto break_or_fail;
1079 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1080 err = nilfs_segctor_apply_buffers(
1081 sci, inode, &node_buffers, sc_ops->collect_bmap);
1082 if (unlikely(err))
1083 goto break_or_fail;
1085 nilfs_segctor_end_finfo(sci, inode);
1086 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1088 break_or_fail:
1089 return err;
1092 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1093 struct inode *inode)
1095 LIST_HEAD(data_buffers);
1096 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1097 int err;
1099 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1100 sci->sc_dsync_start,
1101 sci->sc_dsync_end);
1103 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1104 nilfs_collect_file_data);
1105 if (!err) {
1106 nilfs_segctor_end_finfo(sci, inode);
1107 BUG_ON(n > rest);
1108 /* always receive -E2BIG or true error if n > rest */
1110 return err;
1113 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1115 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1116 struct list_head *head;
1117 struct nilfs_inode_info *ii;
1118 size_t ndone;
1119 int err = 0;
1121 switch (nilfs_sc_cstage_get(sci)) {
1122 case NILFS_ST_INIT:
1123 /* Pre-processes */
1124 sci->sc_stage.flags = 0;
1126 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1127 sci->sc_nblk_inc = 0;
1128 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1129 if (mode == SC_LSEG_DSYNC) {
1130 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1131 goto dsync_mode;
1135 sci->sc_stage.dirty_file_ptr = NULL;
1136 sci->sc_stage.gc_inode_ptr = NULL;
1137 if (mode == SC_FLUSH_DAT) {
1138 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1139 goto dat_stage;
1141 nilfs_sc_cstage_inc(sci); /* Fall through */
1142 case NILFS_ST_GC:
1143 if (nilfs_doing_gc()) {
1144 head = &sci->sc_gc_inodes;
1145 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1146 head, i_dirty);
1147 list_for_each_entry_continue(ii, head, i_dirty) {
1148 err = nilfs_segctor_scan_file(
1149 sci, &ii->vfs_inode,
1150 &nilfs_sc_file_ops);
1151 if (unlikely(err)) {
1152 sci->sc_stage.gc_inode_ptr = list_entry(
1153 ii->i_dirty.prev,
1154 struct nilfs_inode_info,
1155 i_dirty);
1156 goto break_or_fail;
1158 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1160 sci->sc_stage.gc_inode_ptr = NULL;
1162 nilfs_sc_cstage_inc(sci); /* Fall through */
1163 case NILFS_ST_FILE:
1164 head = &sci->sc_dirty_files;
1165 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1166 i_dirty);
1167 list_for_each_entry_continue(ii, head, i_dirty) {
1168 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1170 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1171 &nilfs_sc_file_ops);
1172 if (unlikely(err)) {
1173 sci->sc_stage.dirty_file_ptr =
1174 list_entry(ii->i_dirty.prev,
1175 struct nilfs_inode_info,
1176 i_dirty);
1177 goto break_or_fail;
1179 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1180 /* XXX: required ? */
1182 sci->sc_stage.dirty_file_ptr = NULL;
1183 if (mode == SC_FLUSH_FILE) {
1184 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1185 return 0;
1187 nilfs_sc_cstage_inc(sci);
1188 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1189 /* Fall through */
1190 case NILFS_ST_IFILE:
1191 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1192 &nilfs_sc_file_ops);
1193 if (unlikely(err))
1194 break;
1195 nilfs_sc_cstage_inc(sci);
1196 /* Creating a checkpoint */
1197 err = nilfs_segctor_create_checkpoint(sci);
1198 if (unlikely(err))
1199 break;
1200 /* Fall through */
1201 case NILFS_ST_CPFILE:
1202 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1203 &nilfs_sc_file_ops);
1204 if (unlikely(err))
1205 break;
1206 nilfs_sc_cstage_inc(sci); /* Fall through */
1207 case NILFS_ST_SUFILE:
1208 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1209 sci->sc_nfreesegs, &ndone);
1210 if (unlikely(err)) {
1211 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1212 sci->sc_freesegs, ndone,
1213 NULL);
1214 break;
1216 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1218 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1219 &nilfs_sc_file_ops);
1220 if (unlikely(err))
1221 break;
1222 nilfs_sc_cstage_inc(sci); /* Fall through */
1223 case NILFS_ST_DAT:
1224 dat_stage:
1225 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1226 &nilfs_sc_dat_ops);
1227 if (unlikely(err))
1228 break;
1229 if (mode == SC_FLUSH_DAT) {
1230 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1231 return 0;
1233 nilfs_sc_cstage_inc(sci); /* Fall through */
1234 case NILFS_ST_SR:
1235 if (mode == SC_LSEG_SR) {
1236 /* Appending a super root */
1237 err = nilfs_segctor_add_super_root(sci);
1238 if (unlikely(err))
1239 break;
1241 /* End of a logical segment */
1242 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1243 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1244 return 0;
1245 case NILFS_ST_DSYNC:
1246 dsync_mode:
1247 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1248 ii = sci->sc_dsync_inode;
1249 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1250 break;
1252 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1253 if (unlikely(err))
1254 break;
1255 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1256 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1257 return 0;
1258 case NILFS_ST_DONE:
1259 return 0;
1260 default:
1261 BUG();
1264 break_or_fail:
1265 return err;
1269 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1270 * @sci: nilfs_sc_info
1271 * @nilfs: nilfs object
1273 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1274 struct the_nilfs *nilfs)
1276 struct nilfs_segment_buffer *segbuf, *prev;
1277 __u64 nextnum;
1278 int err, alloc = 0;
1280 segbuf = nilfs_segbuf_new(sci->sc_super);
1281 if (unlikely(!segbuf))
1282 return -ENOMEM;
1284 if (list_empty(&sci->sc_write_logs)) {
1285 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1286 nilfs->ns_pseg_offset, nilfs);
1287 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1288 nilfs_shift_to_next_segment(nilfs);
1289 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1292 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1293 nextnum = nilfs->ns_nextnum;
1295 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1296 /* Start from the head of a new full segment */
1297 alloc++;
1298 } else {
1299 /* Continue logs */
1300 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1301 nilfs_segbuf_map_cont(segbuf, prev);
1302 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1303 nextnum = prev->sb_nextnum;
1305 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1306 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1307 segbuf->sb_sum.seg_seq++;
1308 alloc++;
1312 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1313 if (err)
1314 goto failed;
1316 if (alloc) {
1317 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1318 if (err)
1319 goto failed;
1321 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1323 BUG_ON(!list_empty(&sci->sc_segbufs));
1324 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1325 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1326 return 0;
1328 failed:
1329 nilfs_segbuf_free(segbuf);
1330 return err;
1333 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1334 struct the_nilfs *nilfs, int nadd)
1336 struct nilfs_segment_buffer *segbuf, *prev;
1337 struct inode *sufile = nilfs->ns_sufile;
1338 __u64 nextnextnum;
1339 LIST_HEAD(list);
1340 int err, ret, i;
1342 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1344 * Since the segment specified with nextnum might be allocated during
1345 * the previous construction, the buffer including its segusage may
1346 * not be dirty. The following call ensures that the buffer is dirty
1347 * and will pin the buffer on memory until the sufile is written.
1349 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1350 if (unlikely(err))
1351 return err;
1353 for (i = 0; i < nadd; i++) {
1354 /* extend segment info */
1355 err = -ENOMEM;
1356 segbuf = nilfs_segbuf_new(sci->sc_super);
1357 if (unlikely(!segbuf))
1358 goto failed;
1360 /* map this buffer to region of segment on-disk */
1361 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1362 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1364 /* allocate the next next full segment */
1365 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1366 if (unlikely(err))
1367 goto failed_segbuf;
1369 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1370 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1372 list_add_tail(&segbuf->sb_list, &list);
1373 prev = segbuf;
1375 list_splice_tail(&list, &sci->sc_segbufs);
1376 return 0;
1378 failed_segbuf:
1379 nilfs_segbuf_free(segbuf);
1380 failed:
1381 list_for_each_entry(segbuf, &list, sb_list) {
1382 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1383 WARN_ON(ret); /* never fails */
1385 nilfs_destroy_logs(&list);
1386 return err;
1389 static void nilfs_free_incomplete_logs(struct list_head *logs,
1390 struct the_nilfs *nilfs)
1392 struct nilfs_segment_buffer *segbuf, *prev;
1393 struct inode *sufile = nilfs->ns_sufile;
1394 int ret;
1396 segbuf = NILFS_FIRST_SEGBUF(logs);
1397 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1398 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1399 WARN_ON(ret); /* never fails */
1401 if (atomic_read(&segbuf->sb_err)) {
1402 /* Case 1: The first segment failed */
1403 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1405 * Case 1a: Partial segment appended into an existing
1406 * segment
1408 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1409 segbuf->sb_fseg_end);
1410 else /* Case 1b: New full segment */
1411 set_nilfs_discontinued(nilfs);
1414 prev = segbuf;
1415 list_for_each_entry_continue(segbuf, logs, sb_list) {
1416 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1417 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1418 WARN_ON(ret); /* never fails */
1420 if (atomic_read(&segbuf->sb_err) &&
1421 segbuf->sb_segnum != nilfs->ns_nextnum)
1422 /* Case 2: extended segment (!= next) failed */
1423 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1424 prev = segbuf;
1428 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1429 struct inode *sufile)
1431 struct nilfs_segment_buffer *segbuf;
1432 unsigned long live_blocks;
1433 int ret;
1435 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1436 live_blocks = segbuf->sb_sum.nblocks +
1437 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1438 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1439 live_blocks,
1440 sci->sc_seg_ctime);
1441 WARN_ON(ret); /* always succeed because the segusage is dirty */
1445 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1447 struct nilfs_segment_buffer *segbuf;
1448 int ret;
1450 segbuf = NILFS_FIRST_SEGBUF(logs);
1451 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1452 segbuf->sb_pseg_start -
1453 segbuf->sb_fseg_start, 0);
1454 WARN_ON(ret); /* always succeed because the segusage is dirty */
1456 list_for_each_entry_continue(segbuf, logs, sb_list) {
1457 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1458 0, 0);
1459 WARN_ON(ret); /* always succeed */
1463 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1464 struct nilfs_segment_buffer *last,
1465 struct inode *sufile)
1467 struct nilfs_segment_buffer *segbuf = last;
1468 int ret;
1470 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1471 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1472 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1473 WARN_ON(ret);
1475 nilfs_truncate_logs(&sci->sc_segbufs, last);
1479 static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1480 struct the_nilfs *nilfs, int mode)
1482 struct nilfs_cstage prev_stage = sci->sc_stage;
1483 int err, nadd = 1;
1485 /* Collection retry loop */
1486 for (;;) {
1487 sci->sc_nblk_this_inc = 0;
1488 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1490 err = nilfs_segctor_reset_segment_buffer(sci);
1491 if (unlikely(err))
1492 goto failed;
1494 err = nilfs_segctor_collect_blocks(sci, mode);
1495 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1496 if (!err)
1497 break;
1499 if (unlikely(err != -E2BIG))
1500 goto failed;
1502 /* The current segment is filled up */
1503 if (mode != SC_LSEG_SR ||
1504 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1505 break;
1507 nilfs_clear_logs(&sci->sc_segbufs);
1509 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1510 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1511 sci->sc_freesegs,
1512 sci->sc_nfreesegs,
1513 NULL);
1514 WARN_ON(err); /* do not happen */
1515 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1518 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1519 if (unlikely(err))
1520 return err;
1522 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1523 sci->sc_stage = prev_stage;
1525 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1526 return 0;
1528 failed:
1529 return err;
1532 static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1533 struct buffer_head *new_bh)
1535 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1537 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1538 /* The caller must release old_bh */
1541 static int
1542 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1543 struct nilfs_segment_buffer *segbuf,
1544 int mode)
1546 struct inode *inode = NULL;
1547 sector_t blocknr;
1548 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1549 unsigned long nblocks = 0, ndatablk = 0;
1550 const struct nilfs_sc_operations *sc_op = NULL;
1551 struct nilfs_segsum_pointer ssp;
1552 struct nilfs_finfo *finfo = NULL;
1553 union nilfs_binfo binfo;
1554 struct buffer_head *bh, *bh_org;
1555 ino_t ino = 0;
1556 int err = 0;
1558 if (!nfinfo)
1559 goto out;
1561 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1562 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1563 ssp.offset = sizeof(struct nilfs_segment_summary);
1565 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1566 if (bh == segbuf->sb_super_root)
1567 break;
1568 if (!finfo) {
1569 finfo = nilfs_segctor_map_segsum_entry(
1570 sci, &ssp, sizeof(*finfo));
1571 ino = le64_to_cpu(finfo->fi_ino);
1572 nblocks = le32_to_cpu(finfo->fi_nblocks);
1573 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1575 inode = bh->b_page->mapping->host;
1577 if (mode == SC_LSEG_DSYNC)
1578 sc_op = &nilfs_sc_dsync_ops;
1579 else if (ino == NILFS_DAT_INO)
1580 sc_op = &nilfs_sc_dat_ops;
1581 else /* file blocks */
1582 sc_op = &nilfs_sc_file_ops;
1584 bh_org = bh;
1585 get_bh(bh_org);
1586 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1587 &binfo);
1588 if (bh != bh_org)
1589 nilfs_list_replace_buffer(bh_org, bh);
1590 brelse(bh_org);
1591 if (unlikely(err))
1592 goto failed_bmap;
1594 if (ndatablk > 0)
1595 sc_op->write_data_binfo(sci, &ssp, &binfo);
1596 else
1597 sc_op->write_node_binfo(sci, &ssp, &binfo);
1599 blocknr++;
1600 if (--nblocks == 0) {
1601 finfo = NULL;
1602 if (--nfinfo == 0)
1603 break;
1604 } else if (ndatablk > 0)
1605 ndatablk--;
1607 out:
1608 return 0;
1610 failed_bmap:
1611 return err;
1614 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1616 struct nilfs_segment_buffer *segbuf;
1617 int err;
1619 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1620 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1621 if (unlikely(err))
1622 return err;
1623 nilfs_segbuf_fill_in_segsum(segbuf);
1625 return 0;
1628 static void nilfs_begin_page_io(struct page *page)
1630 if (!page || PageWriteback(page))
1632 * For split b-tree node pages, this function may be called
1633 * twice. We ignore the 2nd or later calls by this check.
1635 return;
1637 lock_page(page);
1638 clear_page_dirty_for_io(page);
1639 set_page_writeback(page);
1640 unlock_page(page);
1643 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1645 struct nilfs_segment_buffer *segbuf;
1646 struct page *bd_page = NULL, *fs_page = NULL;
1648 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1649 struct buffer_head *bh;
1651 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1652 b_assoc_buffers) {
1653 if (bh->b_page != bd_page) {
1654 if (bd_page) {
1655 lock_page(bd_page);
1656 clear_page_dirty_for_io(bd_page);
1657 set_page_writeback(bd_page);
1658 unlock_page(bd_page);
1660 bd_page = bh->b_page;
1664 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1665 b_assoc_buffers) {
1666 set_buffer_async_write(bh);
1667 if (bh == segbuf->sb_super_root) {
1668 if (bh->b_page != bd_page) {
1669 lock_page(bd_page);
1670 clear_page_dirty_for_io(bd_page);
1671 set_page_writeback(bd_page);
1672 unlock_page(bd_page);
1673 bd_page = bh->b_page;
1675 break;
1677 if (bh->b_page != fs_page) {
1678 nilfs_begin_page_io(fs_page);
1679 fs_page = bh->b_page;
1683 if (bd_page) {
1684 lock_page(bd_page);
1685 clear_page_dirty_for_io(bd_page);
1686 set_page_writeback(bd_page);
1687 unlock_page(bd_page);
1689 nilfs_begin_page_io(fs_page);
1692 static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1693 struct the_nilfs *nilfs)
1695 int ret;
1697 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1698 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1699 return ret;
1702 static void nilfs_end_page_io(struct page *page, int err)
1704 if (!page)
1705 return;
1707 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1709 * For b-tree node pages, this function may be called twice
1710 * or more because they might be split in a segment.
1712 if (PageDirty(page)) {
1714 * For pages holding split b-tree node buffers, dirty
1715 * flag on the buffers may be cleared discretely.
1716 * In that case, the page is once redirtied for
1717 * remaining buffers, and it must be cancelled if
1718 * all the buffers get cleaned later.
1720 lock_page(page);
1721 if (nilfs_page_buffers_clean(page))
1722 __nilfs_clear_page_dirty(page);
1723 unlock_page(page);
1725 return;
1728 if (!err) {
1729 if (!nilfs_page_buffers_clean(page))
1730 __set_page_dirty_nobuffers(page);
1731 ClearPageError(page);
1732 } else {
1733 __set_page_dirty_nobuffers(page);
1734 SetPageError(page);
1737 end_page_writeback(page);
1740 static void nilfs_abort_logs(struct list_head *logs, int err)
1742 struct nilfs_segment_buffer *segbuf;
1743 struct page *bd_page = NULL, *fs_page = NULL;
1744 struct buffer_head *bh;
1746 if (list_empty(logs))
1747 return;
1749 list_for_each_entry(segbuf, logs, sb_list) {
1750 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1751 b_assoc_buffers) {
1752 if (bh->b_page != bd_page) {
1753 if (bd_page)
1754 end_page_writeback(bd_page);
1755 bd_page = bh->b_page;
1759 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1760 b_assoc_buffers) {
1761 clear_buffer_async_write(bh);
1762 if (bh == segbuf->sb_super_root) {
1763 if (bh->b_page != bd_page) {
1764 end_page_writeback(bd_page);
1765 bd_page = bh->b_page;
1767 break;
1769 if (bh->b_page != fs_page) {
1770 nilfs_end_page_io(fs_page, err);
1771 fs_page = bh->b_page;
1775 if (bd_page)
1776 end_page_writeback(bd_page);
1778 nilfs_end_page_io(fs_page, err);
1781 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1782 struct the_nilfs *nilfs, int err)
1784 LIST_HEAD(logs);
1785 int ret;
1787 list_splice_tail_init(&sci->sc_write_logs, &logs);
1788 ret = nilfs_wait_on_logs(&logs);
1789 nilfs_abort_logs(&logs, ret ? : err);
1791 list_splice_tail_init(&sci->sc_segbufs, &logs);
1792 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1793 nilfs_free_incomplete_logs(&logs, nilfs);
1795 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1796 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1797 sci->sc_freesegs,
1798 sci->sc_nfreesegs,
1799 NULL);
1800 WARN_ON(ret); /* do not happen */
1803 nilfs_destroy_logs(&logs);
1806 static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1807 struct nilfs_segment_buffer *segbuf)
1809 nilfs->ns_segnum = segbuf->sb_segnum;
1810 nilfs->ns_nextnum = segbuf->sb_nextnum;
1811 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1812 + segbuf->sb_sum.nblocks;
1813 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1814 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1817 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1819 struct nilfs_segment_buffer *segbuf;
1820 struct page *bd_page = NULL, *fs_page = NULL;
1821 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1822 int update_sr = false;
1824 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1825 struct buffer_head *bh;
1827 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1828 b_assoc_buffers) {
1829 set_buffer_uptodate(bh);
1830 clear_buffer_dirty(bh);
1831 if (bh->b_page != bd_page) {
1832 if (bd_page)
1833 end_page_writeback(bd_page);
1834 bd_page = bh->b_page;
1838 * We assume that the buffers which belong to the same page
1839 * continue over the buffer list.
1840 * Under this assumption, the last BHs of pages is
1841 * identifiable by the discontinuity of bh->b_page
1842 * (page != fs_page).
1844 * For B-tree node blocks, however, this assumption is not
1845 * guaranteed. The cleanup code of B-tree node pages needs
1846 * special care.
1848 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1849 b_assoc_buffers) {
1850 const unsigned long set_bits = BIT(BH_Uptodate);
1851 const unsigned long clear_bits =
1852 (BIT(BH_Dirty) | BIT(BH_Async_Write) |
1853 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) |
1854 BIT(BH_NILFS_Redirected));
1856 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1857 if (bh == segbuf->sb_super_root) {
1858 if (bh->b_page != bd_page) {
1859 end_page_writeback(bd_page);
1860 bd_page = bh->b_page;
1862 update_sr = true;
1863 break;
1865 if (bh->b_page != fs_page) {
1866 nilfs_end_page_io(fs_page, 0);
1867 fs_page = bh->b_page;
1871 if (!nilfs_segbuf_simplex(segbuf)) {
1872 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1873 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1874 sci->sc_lseg_stime = jiffies;
1876 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1877 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1881 * Since pages may continue over multiple segment buffers,
1882 * end of the last page must be checked outside of the loop.
1884 if (bd_page)
1885 end_page_writeback(bd_page);
1887 nilfs_end_page_io(fs_page, 0);
1889 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1891 if (nilfs_doing_gc())
1892 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1893 else
1894 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1896 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1898 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1899 nilfs_set_next_segment(nilfs, segbuf);
1901 if (update_sr) {
1902 nilfs->ns_flushed_device = 0;
1903 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1904 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1906 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1907 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1908 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1909 nilfs_segctor_clear_metadata_dirty(sci);
1910 } else
1911 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1914 static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1916 int ret;
1918 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1919 if (!ret) {
1920 nilfs_segctor_complete_write(sci);
1921 nilfs_destroy_logs(&sci->sc_write_logs);
1923 return ret;
1926 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1927 struct the_nilfs *nilfs)
1929 struct nilfs_inode_info *ii, *n;
1930 struct inode *ifile = sci->sc_root->ifile;
1932 spin_lock(&nilfs->ns_inode_lock);
1933 retry:
1934 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1935 if (!ii->i_bh) {
1936 struct buffer_head *ibh;
1937 int err;
1939 spin_unlock(&nilfs->ns_inode_lock);
1940 err = nilfs_ifile_get_inode_block(
1941 ifile, ii->vfs_inode.i_ino, &ibh);
1942 if (unlikely(err)) {
1943 nilfs_msg(sci->sc_super, KERN_WARNING,
1944 "log writer: error %d getting inode block (ino=%lu)",
1945 err, ii->vfs_inode.i_ino);
1946 return err;
1948 spin_lock(&nilfs->ns_inode_lock);
1949 if (likely(!ii->i_bh))
1950 ii->i_bh = ibh;
1951 else
1952 brelse(ibh);
1953 goto retry;
1956 // Always redirty the buffer to avoid race condition
1957 mark_buffer_dirty(ii->i_bh);
1958 nilfs_mdt_mark_dirty(ifile);
1960 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1961 set_bit(NILFS_I_BUSY, &ii->i_state);
1962 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1964 spin_unlock(&nilfs->ns_inode_lock);
1966 return 0;
1969 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1970 struct the_nilfs *nilfs)
1972 struct nilfs_inode_info *ii, *n;
1973 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
1974 int defer_iput = false;
1976 spin_lock(&nilfs->ns_inode_lock);
1977 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1978 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1979 test_bit(NILFS_I_DIRTY, &ii->i_state))
1980 continue;
1982 clear_bit(NILFS_I_BUSY, &ii->i_state);
1983 brelse(ii->i_bh);
1984 ii->i_bh = NULL;
1985 list_del_init(&ii->i_dirty);
1986 if (!ii->vfs_inode.i_nlink || during_mount) {
1988 * Defer calling iput() to avoid deadlocks if
1989 * i_nlink == 0 or mount is not yet finished.
1991 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
1992 defer_iput = true;
1993 } else {
1994 spin_unlock(&nilfs->ns_inode_lock);
1995 iput(&ii->vfs_inode);
1996 spin_lock(&nilfs->ns_inode_lock);
1999 spin_unlock(&nilfs->ns_inode_lock);
2001 if (defer_iput)
2002 schedule_work(&sci->sc_iput_work);
2006 * Main procedure of segment constructor
2008 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2010 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2011 int err;
2013 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2014 sci->sc_cno = nilfs->ns_cno;
2016 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2017 if (unlikely(err))
2018 goto out;
2020 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2021 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2023 if (nilfs_segctor_clean(sci))
2024 goto out;
2026 do {
2027 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2029 err = nilfs_segctor_begin_construction(sci, nilfs);
2030 if (unlikely(err))
2031 goto out;
2033 /* Update time stamp */
2034 sci->sc_seg_ctime = ktime_get_real_seconds();
2036 err = nilfs_segctor_collect(sci, nilfs, mode);
2037 if (unlikely(err))
2038 goto failed;
2040 /* Avoid empty segment */
2041 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2042 nilfs_segbuf_empty(sci->sc_curseg)) {
2043 nilfs_segctor_abort_construction(sci, nilfs, 1);
2044 goto out;
2047 err = nilfs_segctor_assign(sci, mode);
2048 if (unlikely(err))
2049 goto failed;
2051 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2052 nilfs_segctor_fill_in_file_bmap(sci);
2054 if (mode == SC_LSEG_SR &&
2055 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2056 err = nilfs_segctor_fill_in_checkpoint(sci);
2057 if (unlikely(err))
2058 goto failed_to_write;
2060 nilfs_segctor_fill_in_super_root(sci, nilfs);
2062 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2064 /* Write partial segments */
2065 nilfs_segctor_prepare_write(sci);
2067 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2068 nilfs->ns_crc_seed);
2070 err = nilfs_segctor_write(sci, nilfs);
2071 if (unlikely(err))
2072 goto failed_to_write;
2074 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2075 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2077 * At this point, we avoid double buffering
2078 * for blocksize < pagesize because page dirty
2079 * flag is turned off during write and dirty
2080 * buffers are not properly collected for
2081 * pages crossing over segments.
2083 err = nilfs_segctor_wait(sci);
2084 if (err)
2085 goto failed_to_write;
2087 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2089 out:
2090 nilfs_segctor_drop_written_files(sci, nilfs);
2091 return err;
2093 failed_to_write:
2094 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2095 nilfs_redirty_inodes(&sci->sc_dirty_files);
2097 failed:
2098 if (nilfs_doing_gc())
2099 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2100 nilfs_segctor_abort_construction(sci, nilfs, err);
2101 goto out;
2105 * nilfs_segctor_start_timer - set timer of background write
2106 * @sci: nilfs_sc_info
2108 * If the timer has already been set, it ignores the new request.
2109 * This function MUST be called within a section locking the segment
2110 * semaphore.
2112 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2114 spin_lock(&sci->sc_state_lock);
2115 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2116 sci->sc_timer.expires = jiffies + sci->sc_interval;
2117 add_timer(&sci->sc_timer);
2118 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2120 spin_unlock(&sci->sc_state_lock);
2123 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2125 spin_lock(&sci->sc_state_lock);
2126 if (!(sci->sc_flush_request & BIT(bn))) {
2127 unsigned long prev_req = sci->sc_flush_request;
2129 sci->sc_flush_request |= BIT(bn);
2130 if (!prev_req)
2131 wake_up(&sci->sc_wait_daemon);
2133 spin_unlock(&sci->sc_state_lock);
2137 * nilfs_flush_segment - trigger a segment construction for resource control
2138 * @sb: super block
2139 * @ino: inode number of the file to be flushed out.
2141 void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2143 struct the_nilfs *nilfs = sb->s_fs_info;
2144 struct nilfs_sc_info *sci = nilfs->ns_writer;
2146 if (!sci || nilfs_doing_construction())
2147 return;
2148 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2149 /* assign bit 0 to data files */
2152 struct nilfs_segctor_wait_request {
2153 wait_queue_entry_t wq;
2154 __u32 seq;
2155 int err;
2156 atomic_t done;
2159 static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2161 struct nilfs_segctor_wait_request wait_req;
2162 int err = 0;
2164 spin_lock(&sci->sc_state_lock);
2165 init_wait(&wait_req.wq);
2166 wait_req.err = 0;
2167 atomic_set(&wait_req.done, 0);
2168 wait_req.seq = ++sci->sc_seq_request;
2169 spin_unlock(&sci->sc_state_lock);
2171 init_waitqueue_entry(&wait_req.wq, current);
2172 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2173 set_current_state(TASK_INTERRUPTIBLE);
2174 wake_up(&sci->sc_wait_daemon);
2176 for (;;) {
2177 if (atomic_read(&wait_req.done)) {
2178 err = wait_req.err;
2179 break;
2181 if (!signal_pending(current)) {
2182 schedule();
2183 continue;
2185 err = -ERESTARTSYS;
2186 break;
2188 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2189 return err;
2192 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2194 struct nilfs_segctor_wait_request *wrq, *n;
2195 unsigned long flags;
2197 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2198 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
2199 if (!atomic_read(&wrq->done) &&
2200 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2201 wrq->err = err;
2202 atomic_set(&wrq->done, 1);
2204 if (atomic_read(&wrq->done)) {
2205 wrq->wq.func(&wrq->wq,
2206 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2207 0, NULL);
2210 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2214 * nilfs_construct_segment - construct a logical segment
2215 * @sb: super block
2217 * Return Value: On success, 0 is retured. On errors, one of the following
2218 * negative error code is returned.
2220 * %-EROFS - Read only filesystem.
2222 * %-EIO - I/O error
2224 * %-ENOSPC - No space left on device (only in a panic state).
2226 * %-ERESTARTSYS - Interrupted.
2228 * %-ENOMEM - Insufficient memory available.
2230 int nilfs_construct_segment(struct super_block *sb)
2232 struct the_nilfs *nilfs = sb->s_fs_info;
2233 struct nilfs_sc_info *sci = nilfs->ns_writer;
2234 struct nilfs_transaction_info *ti;
2235 int err;
2237 if (!sci)
2238 return -EROFS;
2240 /* A call inside transactions causes a deadlock. */
2241 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2243 err = nilfs_segctor_sync(sci);
2244 return err;
2248 * nilfs_construct_dsync_segment - construct a data-only logical segment
2249 * @sb: super block
2250 * @inode: inode whose data blocks should be written out
2251 * @start: start byte offset
2252 * @end: end byte offset (inclusive)
2254 * Return Value: On success, 0 is retured. On errors, one of the following
2255 * negative error code is returned.
2257 * %-EROFS - Read only filesystem.
2259 * %-EIO - I/O error
2261 * %-ENOSPC - No space left on device (only in a panic state).
2263 * %-ERESTARTSYS - Interrupted.
2265 * %-ENOMEM - Insufficient memory available.
2267 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2268 loff_t start, loff_t end)
2270 struct the_nilfs *nilfs = sb->s_fs_info;
2271 struct nilfs_sc_info *sci = nilfs->ns_writer;
2272 struct nilfs_inode_info *ii;
2273 struct nilfs_transaction_info ti;
2274 int err = 0;
2276 if (!sci)
2277 return -EROFS;
2279 nilfs_transaction_lock(sb, &ti, 0);
2281 ii = NILFS_I(inode);
2282 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2283 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2284 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2285 nilfs_discontinued(nilfs)) {
2286 nilfs_transaction_unlock(sb);
2287 err = nilfs_segctor_sync(sci);
2288 return err;
2291 spin_lock(&nilfs->ns_inode_lock);
2292 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2293 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2294 spin_unlock(&nilfs->ns_inode_lock);
2295 nilfs_transaction_unlock(sb);
2296 return 0;
2298 spin_unlock(&nilfs->ns_inode_lock);
2299 sci->sc_dsync_inode = ii;
2300 sci->sc_dsync_start = start;
2301 sci->sc_dsync_end = end;
2303 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2304 if (!err)
2305 nilfs->ns_flushed_device = 0;
2307 nilfs_transaction_unlock(sb);
2308 return err;
2311 #define FLUSH_FILE_BIT (0x1) /* data file only */
2312 #define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2315 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2316 * @sci: segment constructor object
2318 static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2320 spin_lock(&sci->sc_state_lock);
2321 sci->sc_seq_accepted = sci->sc_seq_request;
2322 spin_unlock(&sci->sc_state_lock);
2323 del_timer_sync(&sci->sc_timer);
2327 * nilfs_segctor_notify - notify the result of request to caller threads
2328 * @sci: segment constructor object
2329 * @mode: mode of log forming
2330 * @err: error code to be notified
2332 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2334 /* Clear requests (even when the construction failed) */
2335 spin_lock(&sci->sc_state_lock);
2337 if (mode == SC_LSEG_SR) {
2338 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2339 sci->sc_seq_done = sci->sc_seq_accepted;
2340 nilfs_segctor_wakeup(sci, err);
2341 sci->sc_flush_request = 0;
2342 } else {
2343 if (mode == SC_FLUSH_FILE)
2344 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2345 else if (mode == SC_FLUSH_DAT)
2346 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2348 /* re-enable timer if checkpoint creation was not done */
2349 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2350 time_before(jiffies, sci->sc_timer.expires))
2351 add_timer(&sci->sc_timer);
2353 spin_unlock(&sci->sc_state_lock);
2357 * nilfs_segctor_construct - form logs and write them to disk
2358 * @sci: segment constructor object
2359 * @mode: mode of log forming
2361 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2363 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2364 struct nilfs_super_block **sbp;
2365 int err = 0;
2367 nilfs_segctor_accept(sci);
2369 if (nilfs_discontinued(nilfs))
2370 mode = SC_LSEG_SR;
2371 if (!nilfs_segctor_confirm(sci))
2372 err = nilfs_segctor_do_construct(sci, mode);
2374 if (likely(!err)) {
2375 if (mode != SC_FLUSH_DAT)
2376 atomic_set(&nilfs->ns_ndirtyblks, 0);
2377 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2378 nilfs_discontinued(nilfs)) {
2379 down_write(&nilfs->ns_sem);
2380 err = -EIO;
2381 sbp = nilfs_prepare_super(sci->sc_super,
2382 nilfs_sb_will_flip(nilfs));
2383 if (likely(sbp)) {
2384 nilfs_set_log_cursor(sbp[0], nilfs);
2385 err = nilfs_commit_super(sci->sc_super,
2386 NILFS_SB_COMMIT);
2388 up_write(&nilfs->ns_sem);
2392 nilfs_segctor_notify(sci, mode, err);
2393 return err;
2396 static void nilfs_construction_timeout(struct timer_list *t)
2398 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2400 wake_up_process(sci->sc_timer_task);
2403 static void
2404 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2406 struct nilfs_inode_info *ii, *n;
2408 list_for_each_entry_safe(ii, n, head, i_dirty) {
2409 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2410 continue;
2411 list_del_init(&ii->i_dirty);
2412 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2413 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2414 iput(&ii->vfs_inode);
2418 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2419 void **kbufs)
2421 struct the_nilfs *nilfs = sb->s_fs_info;
2422 struct nilfs_sc_info *sci = nilfs->ns_writer;
2423 struct nilfs_transaction_info ti;
2424 int err;
2426 if (unlikely(!sci))
2427 return -EROFS;
2429 nilfs_transaction_lock(sb, &ti, 1);
2431 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2432 if (unlikely(err))
2433 goto out_unlock;
2435 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2436 if (unlikely(err)) {
2437 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2438 goto out_unlock;
2441 sci->sc_freesegs = kbufs[4];
2442 sci->sc_nfreesegs = argv[4].v_nmembs;
2443 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2445 for (;;) {
2446 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2447 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2449 if (likely(!err))
2450 break;
2452 nilfs_msg(sb, KERN_WARNING, "error %d cleaning segments", err);
2453 set_current_state(TASK_INTERRUPTIBLE);
2454 schedule_timeout(sci->sc_interval);
2456 if (nilfs_test_opt(nilfs, DISCARD)) {
2457 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2458 sci->sc_nfreesegs);
2459 if (ret) {
2460 nilfs_msg(sb, KERN_WARNING,
2461 "error %d on discard request, turning discards off for the device",
2462 ret);
2463 nilfs_clear_opt(nilfs, DISCARD);
2467 out_unlock:
2468 sci->sc_freesegs = NULL;
2469 sci->sc_nfreesegs = 0;
2470 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2471 nilfs_transaction_unlock(sb);
2472 return err;
2475 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2477 struct nilfs_transaction_info ti;
2479 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2480 nilfs_segctor_construct(sci, mode);
2483 * Unclosed segment should be retried. We do this using sc_timer.
2484 * Timeout of sc_timer will invoke complete construction which leads
2485 * to close the current logical segment.
2487 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2488 nilfs_segctor_start_timer(sci);
2490 nilfs_transaction_unlock(sci->sc_super);
2493 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2495 int mode = 0;
2497 spin_lock(&sci->sc_state_lock);
2498 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2499 SC_FLUSH_DAT : SC_FLUSH_FILE;
2500 spin_unlock(&sci->sc_state_lock);
2502 if (mode) {
2503 nilfs_segctor_do_construct(sci, mode);
2505 spin_lock(&sci->sc_state_lock);
2506 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2507 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2508 spin_unlock(&sci->sc_state_lock);
2510 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2513 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2515 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2516 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2517 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2518 return SC_FLUSH_FILE;
2519 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2520 return SC_FLUSH_DAT;
2522 return SC_LSEG_SR;
2526 * nilfs_segctor_thread - main loop of the segment constructor thread.
2527 * @arg: pointer to a struct nilfs_sc_info.
2529 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2530 * to execute segment constructions.
2532 static int nilfs_segctor_thread(void *arg)
2534 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2535 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2536 int timeout = 0;
2538 sci->sc_timer_task = current;
2540 /* start sync. */
2541 sci->sc_task = current;
2542 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2543 nilfs_msg(sci->sc_super, KERN_INFO,
2544 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
2545 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2547 spin_lock(&sci->sc_state_lock);
2548 loop:
2549 for (;;) {
2550 int mode;
2552 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2553 goto end_thread;
2555 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2556 mode = SC_LSEG_SR;
2557 else if (sci->sc_flush_request)
2558 mode = nilfs_segctor_flush_mode(sci);
2559 else
2560 break;
2562 spin_unlock(&sci->sc_state_lock);
2563 nilfs_segctor_thread_construct(sci, mode);
2564 spin_lock(&sci->sc_state_lock);
2565 timeout = 0;
2569 if (freezing(current)) {
2570 spin_unlock(&sci->sc_state_lock);
2571 try_to_freeze();
2572 spin_lock(&sci->sc_state_lock);
2573 } else {
2574 DEFINE_WAIT(wait);
2575 int should_sleep = 1;
2577 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2578 TASK_INTERRUPTIBLE);
2580 if (sci->sc_seq_request != sci->sc_seq_done)
2581 should_sleep = 0;
2582 else if (sci->sc_flush_request)
2583 should_sleep = 0;
2584 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2585 should_sleep = time_before(jiffies,
2586 sci->sc_timer.expires);
2588 if (should_sleep) {
2589 spin_unlock(&sci->sc_state_lock);
2590 schedule();
2591 spin_lock(&sci->sc_state_lock);
2593 finish_wait(&sci->sc_wait_daemon, &wait);
2594 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2595 time_after_eq(jiffies, sci->sc_timer.expires));
2597 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2598 set_nilfs_discontinued(nilfs);
2600 goto loop;
2602 end_thread:
2603 spin_unlock(&sci->sc_state_lock);
2605 /* end sync. */
2606 sci->sc_task = NULL;
2607 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2608 return 0;
2611 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2613 struct task_struct *t;
2615 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2616 if (IS_ERR(t)) {
2617 int err = PTR_ERR(t);
2619 nilfs_msg(sci->sc_super, KERN_ERR,
2620 "error %d creating segctord thread", err);
2621 return err;
2623 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2624 return 0;
2627 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2628 __acquires(&sci->sc_state_lock)
2629 __releases(&sci->sc_state_lock)
2631 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2633 while (sci->sc_task) {
2634 wake_up(&sci->sc_wait_daemon);
2635 spin_unlock(&sci->sc_state_lock);
2636 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2637 spin_lock(&sci->sc_state_lock);
2642 * Setup & clean-up functions
2644 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2645 struct nilfs_root *root)
2647 struct the_nilfs *nilfs = sb->s_fs_info;
2648 struct nilfs_sc_info *sci;
2650 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2651 if (!sci)
2652 return NULL;
2654 sci->sc_super = sb;
2656 nilfs_get_root(root);
2657 sci->sc_root = root;
2659 init_waitqueue_head(&sci->sc_wait_request);
2660 init_waitqueue_head(&sci->sc_wait_daemon);
2661 init_waitqueue_head(&sci->sc_wait_task);
2662 spin_lock_init(&sci->sc_state_lock);
2663 INIT_LIST_HEAD(&sci->sc_dirty_files);
2664 INIT_LIST_HEAD(&sci->sc_segbufs);
2665 INIT_LIST_HEAD(&sci->sc_write_logs);
2666 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2667 INIT_LIST_HEAD(&sci->sc_iput_queue);
2668 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2669 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
2671 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2672 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2673 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2675 if (nilfs->ns_interval)
2676 sci->sc_interval = HZ * nilfs->ns_interval;
2677 if (nilfs->ns_watermark)
2678 sci->sc_watermark = nilfs->ns_watermark;
2679 return sci;
2682 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2684 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2687 * The segctord thread was stopped and its timer was removed.
2688 * But some tasks remain.
2690 do {
2691 struct nilfs_transaction_info ti;
2693 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2694 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2695 nilfs_transaction_unlock(sci->sc_super);
2697 flush_work(&sci->sc_iput_work);
2699 } while (ret && retrycount-- > 0);
2703 * nilfs_segctor_destroy - destroy the segment constructor.
2704 * @sci: nilfs_sc_info
2706 * nilfs_segctor_destroy() kills the segctord thread and frees
2707 * the nilfs_sc_info struct.
2708 * Caller must hold the segment semaphore.
2710 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2712 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2713 int flag;
2715 up_write(&nilfs->ns_segctor_sem);
2717 spin_lock(&sci->sc_state_lock);
2718 nilfs_segctor_kill_thread(sci);
2719 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2720 || sci->sc_seq_request != sci->sc_seq_done);
2721 spin_unlock(&sci->sc_state_lock);
2723 if (flush_work(&sci->sc_iput_work))
2724 flag = true;
2726 if (flag || !nilfs_segctor_confirm(sci))
2727 nilfs_segctor_write_out(sci);
2729 if (!list_empty(&sci->sc_dirty_files)) {
2730 nilfs_msg(sci->sc_super, KERN_WARNING,
2731 "disposed unprocessed dirty file(s) when stopping log writer");
2732 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2735 if (!list_empty(&sci->sc_iput_queue)) {
2736 nilfs_msg(sci->sc_super, KERN_WARNING,
2737 "disposed unprocessed inode(s) in iput queue when stopping log writer");
2738 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2741 WARN_ON(!list_empty(&sci->sc_segbufs));
2742 WARN_ON(!list_empty(&sci->sc_write_logs));
2744 nilfs_put_root(sci->sc_root);
2746 down_write(&nilfs->ns_segctor_sem);
2748 del_timer_sync(&sci->sc_timer);
2749 kfree(sci);
2753 * nilfs_attach_log_writer - attach log writer
2754 * @sb: super block instance
2755 * @root: root object of the current filesystem tree
2757 * This allocates a log writer object, initializes it, and starts the
2758 * log writer.
2760 * Return Value: On success, 0 is returned. On error, one of the following
2761 * negative error code is returned.
2763 * %-ENOMEM - Insufficient memory available.
2765 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2767 struct the_nilfs *nilfs = sb->s_fs_info;
2768 int err;
2770 if (nilfs->ns_writer) {
2772 * This happens if the filesystem was remounted
2773 * read/write after nilfs_error degenerated it into a
2774 * read-only mount.
2776 nilfs_detach_log_writer(sb);
2779 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2780 if (!nilfs->ns_writer)
2781 return -ENOMEM;
2783 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2784 if (err) {
2785 kfree(nilfs->ns_writer);
2786 nilfs->ns_writer = NULL;
2788 return err;
2792 * nilfs_detach_log_writer - destroy log writer
2793 * @sb: super block instance
2795 * This kills log writer daemon, frees the log writer object, and
2796 * destroys list of dirty files.
2798 void nilfs_detach_log_writer(struct super_block *sb)
2800 struct the_nilfs *nilfs = sb->s_fs_info;
2801 LIST_HEAD(garbage_list);
2803 down_write(&nilfs->ns_segctor_sem);
2804 if (nilfs->ns_writer) {
2805 nilfs_segctor_destroy(nilfs->ns_writer);
2806 nilfs->ns_writer = NULL;
2809 /* Force to free the list of dirty files */
2810 spin_lock(&nilfs->ns_inode_lock);
2811 if (!list_empty(&nilfs->ns_dirty_files)) {
2812 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2813 nilfs_msg(sb, KERN_WARNING,
2814 "disposed unprocessed dirty file(s) when detaching log writer");
2816 spin_unlock(&nilfs->ns_inode_lock);
2817 up_write(&nilfs->ns_segctor_sem);
2819 nilfs_dispose_list(nilfs, &garbage_list, 1);