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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * segment.c - NILFS segment constructor.
4 *
5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Ryusuke Konishi.
8 *
9 */
10
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>
25
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"
34
35
36/*
37 * Segment constructor
38 */
39#define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
40
41#define SC_MAX_SEGDELTA 64 /*
42 * Upper limit of the number of segments
43 * appended in collection retry loop
44 */
45
46/* Construction mode */
47enum {
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.
52 */
53 SC_FLUSH_FILE, /*
54 * Flush data files, leads to segment writes without
55 * creating a checkpoint.
56 */
57 SC_FLUSH_DAT, /*
58 * Flush DAT file. This also creates segments
59 * without a checkpoint.
60 */
61};
62
63/* Stage numbers of dirty block collection */
64enum {
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,
75};
76
77#define CREATE_TRACE_POINTS
78#include <trace/events/nilfs2.h>
79
80/*
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).
85 *
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.
89 */
90static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
91{
92 sci->sc_stage.scnt++;
93 trace_nilfs2_collection_stage_transition(sci);
94}
95
96static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
97{
98 sci->sc_stage.scnt = next_scnt;
99 trace_nilfs2_collection_stage_transition(sci);
100}
101
102static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
103{
104 return sci->sc_stage.scnt;
105}
106
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)
112
113/* Operations depending on the construction mode and file type */
114struct 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 *);
127};
128
129/*
130 * Other definitions
131 */
132static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
133static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
134static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
135static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
136
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)
145
146static int nilfs_prepare_segment_lock(struct super_block *sb,
147 struct nilfs_transaction_info *ti)
148{
149 struct nilfs_transaction_info *cur_ti = current->journal_info;
150 void *save = NULL;
151
152 if (cur_ti) {
153 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
154 return ++cur_ti->ti_count;
155
156 /*
157 * If journal_info field is occupied by other FS,
158 * it is saved and will be restored on
159 * nilfs_transaction_commit().
160 */
161 nilfs_msg(sb, KERN_WARNING, "journal info from a different FS");
162 save = current->journal_info;
163 }
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;
171 }
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;
177}
178
179/**
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
184 *
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.
190 *
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.
195 *
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.
198 *
199 * Return Value: On success, 0 is returned. On error, one of the following
200 * negative error code is returned.
201 *
202 * %-ENOMEM - Insufficient memory available.
203 *
204 * %-ENOSPC - No space left on device
205 */
206int nilfs_transaction_begin(struct super_block *sb,
207 struct nilfs_transaction_info *ti,
208 int vacancy_check)
209{
210 struct the_nilfs *nilfs;
211 int ret = nilfs_prepare_segment_lock(sb, ti);
212 struct nilfs_transaction_info *trace_ti;
213
214 if (unlikely(ret < 0))
215 return ret;
216 if (ret > 0) {
217 trace_ti = current->journal_info;
218
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;
223 }
224
225 sb_start_intwrite(sb);
226
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;
233 }
234
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;
240
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;
248}
249
250/**
251 * nilfs_transaction_commit - commit indivisible file operations.
252 * @sb: super block
253 *
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.
260 */
261int nilfs_transaction_commit(struct super_block *sb)
262{
263 struct nilfs_transaction_info *ti = current->journal_info;
264 struct the_nilfs *nilfs = sb->s_fs_info;
265 int err = 0;
266
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;
274 }
275 if (nilfs->ns_writer) {
276 struct nilfs_sc_info *sci = nilfs->ns_writer;
277
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);
282 }
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);
286
287 current->journal_info = ti->ti_save;
288
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;
295}
296
297void nilfs_transaction_abort(struct super_block *sb)
298{
299 struct nilfs_transaction_info *ti = current->journal_info;
300 struct the_nilfs *nilfs = sb->s_fs_info;
301
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;
308 }
309 up_read(&nilfs->ns_segctor_sem);
310
311 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
312 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
313
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);
318}
319
320void nilfs_relax_pressure_in_lock(struct super_block *sb)
321{
322 struct the_nilfs *nilfs = sb->s_fs_info;
323 struct nilfs_sc_info *sci = nilfs->ns_writer;
324
325 if (!sci || !sci->sc_flush_request)
326 return;
327
328 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
329 up_read(&nilfs->ns_segctor_sem);
330
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;
335
336 ti->ti_flags |= NILFS_TI_WRITER;
337 nilfs_segctor_do_immediate_flush(sci);
338 ti->ti_flags &= ~NILFS_TI_WRITER;
339 }
340 downgrade_write(&nilfs->ns_segctor_sem);
341}
342
343static void nilfs_transaction_lock(struct super_block *sb,
344 struct nilfs_transaction_info *ti,
345 int gcflag)
346{
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;
350
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;
357
358 for (;;) {
359 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
360 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
361
362 down_write(&nilfs->ns_segctor_sem);
363 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
364 break;
365
366 nilfs_segctor_do_immediate_flush(sci);
367
368 up_write(&nilfs->ns_segctor_sem);
369 cond_resched();
370 }
371 if (gcflag)
372 ti->ti_flags |= NILFS_TI_GC;
373
374 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
375 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
376}
377
378static void nilfs_transaction_unlock(struct super_block *sb)
379{
380 struct nilfs_transaction_info *ti = current->journal_info;
381 struct the_nilfs *nilfs = sb->s_fs_info;
382
383 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
384 BUG_ON(ti->ti_count > 0);
385
386 up_write(&nilfs->ns_segctor_sem);
387 current->journal_info = ti->ti_save;
388
389 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
390 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
391}
392
393static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
394 struct nilfs_segsum_pointer *ssp,
395 unsigned int bytes)
396{
397 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
398 unsigned int blocksize = sci->sc_super->s_blocksize;
399 void *p;
400
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);
406 }
407 p = ssp->bh->b_data + ssp->offset;
408 ssp->offset += bytes;
409 return p;
410}
411
412/**
413 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
414 * @sci: nilfs_sc_info
415 */
416static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
417{
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;
423
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;
429
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;
436}
437
438static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
439{
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)
445 */
446 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
447 return nilfs_segctor_reset_segment_buffer(sci);
448}
449
450static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
451{
452 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
453 int err;
454
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;
460 }
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;
465}
466
467/*
468 * Functions for making segment summary and payloads
469 */
470static int nilfs_segctor_segsum_block_required(
471 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
472 unsigned int binfo_size)
473{
474 unsigned int blocksize = sci->sc_super->s_blocksize;
475 /* Size of finfo and binfo is enough small against blocksize */
476
477 return ssp->offset + binfo_size +
478 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
479 blocksize;
480}
481
482static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
483 struct inode *inode)
484{
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));
489
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 */
494}
495
496static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
497 struct inode *inode)
498{
499 struct nilfs_finfo *finfo;
500 struct nilfs_inode_info *ii;
501 struct nilfs_segment_buffer *segbuf;
502 __u64 cno;
503
504 if (sci->sc_blk_cnt == 0)
505 return;
506
507 ii = NILFS_I(inode);
508
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;
515
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);
522
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;
528}
529
530static 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)
534{
535 struct nilfs_segment_buffer *segbuf;
536 int required, err = 0;
537
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;
548 }
549 if (unlikely(required)) {
550 err = nilfs_segbuf_extend_segsum(segbuf);
551 if (unlikely(err))
552 goto failed;
553 }
554 if (sci->sc_blk_cnt == 0)
555 nilfs_segctor_begin_finfo(sci, inode);
556
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;
563}
564
565/*
566 * Callback functions that enumerate, mark, and collect dirty blocks
567 */
568static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
569 struct buffer_head *bh, struct inode *inode)
570{
571 int err;
572
573 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
574 if (err < 0)
575 return err;
576
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;
582}
583
584static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
585 struct buffer_head *bh,
586 struct inode *inode)
587{
588 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
589}
590
591static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
592 struct buffer_head *bh,
593 struct inode *inode)
594{
595 WARN_ON(!buffer_dirty(bh));
596 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
597}
598
599static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
600 struct nilfs_segsum_pointer *ssp,
601 union nilfs_binfo *binfo)
602{
603 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
604 sci, ssp, sizeof(*binfo_v));
605 *binfo_v = binfo->bi_v;
606}
607
608static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
609 struct nilfs_segsum_pointer *ssp,
610 union nilfs_binfo *binfo)
611{
612 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
613 sci, ssp, sizeof(*vblocknr));
614 *vblocknr = binfo->bi_v.bi_vblocknr;
615}
616
617static 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,
623};
624
625static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
626 struct buffer_head *bh, struct inode *inode)
627{
628 int err;
629
630 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
631 if (err < 0)
632 return err;
633
634 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
635 if (!err)
636 sci->sc_datablk_cnt++;
637 return err;
638}
639
640static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
641 struct buffer_head *bh, struct inode *inode)
642{
643 WARN_ON(!buffer_dirty(bh));
644 return nilfs_segctor_add_file_block(sci, bh, inode,
645 sizeof(struct nilfs_binfo_dat));
646}
647
648static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
649 struct nilfs_segsum_pointer *ssp,
650 union nilfs_binfo *binfo)
651{
652 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
653 sizeof(*blkoff));
654 *blkoff = binfo->bi_dat.bi_blkoff;
655}
656
657static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
658 struct nilfs_segsum_pointer *ssp,
659 union nilfs_binfo *binfo)
660{
661 struct nilfs_binfo_dat *binfo_dat =
662 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
663 *binfo_dat = binfo->bi_dat;
664}
665
666static 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,
672};
673
674static 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,
680};
681
682static 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)
686{
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;
692
693 if (unlikely(start != 0 || end != LLONG_MAX)) {
694 /*
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.
698 */
699 index = start >> PAGE_SHIFT;
700 last = end >> PAGE_SHIFT;
701 }
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;
708
709 for (i = 0; i < pagevec_count(&pvec); i++) {
710 struct buffer_head *bh, *head;
711 struct page *page = pvec.pages[i];
712
713 lock_page(page);
714 if (!page_has_buffers(page))
715 create_empty_buffers(page, i_blocksize(inode), 0);
716 unlock_page(page);
717
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;
729 }
730 } while (bh = bh->b_this_page, bh != head);
731 }
732 pagevec_release(&pvec);
733 cond_resched();
734 goto repeat;
735}
736
737static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
738 struct list_head *listp)
739{
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;
746
747 pagevec_init(&pvec);
748
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);
759 }
760 bh = bh->b_this_page;
761 } while (bh != head);
762 }
763 pagevec_release(&pvec);
764 cond_resched();
765 }
766}
767
768static void nilfs_dispose_list(struct the_nilfs *nilfs,
769 struct list_head *head, int force)
770{
771 struct nilfs_inode_info *ii, *n;
772 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
773 unsigned int nv = 0;
774
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;
783 }
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;
789 }
790 ivec[nv++] = ii;
791 if (nv == SC_N_INODEVEC)
792 break;
793 }
794 spin_unlock(&nilfs->ns_inode_lock);
795
796 for (pii = ivec; nv > 0; pii++, nv--)
797 iput(&(*pii)->vfs_inode);
798 }
799}
800
801static void nilfs_iput_work_func(struct work_struct *work)
802{
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;
806
807 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
808}
809
810static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
811 struct nilfs_root *root)
812{
813 int ret = 0;
814
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;
824}
825
826static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
827{
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));
832}
833
834static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
835{
836 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
837 int ret = 0;
838
839 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
840 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
841
842 spin_lock(&nilfs->ns_inode_lock);
843 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
844 ret++;
845
846 spin_unlock(&nilfs->ns_inode_lock);
847 return ret;
848}
849
850static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
851{
852 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
853
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);
858}
859
860static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
861{
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;
866
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)) {
871 /*
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.
875 */
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);
882
883 return err;
884}
885
886static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
887{
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;
892
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;
898 }
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);
909
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);
914
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;
919
920 failed_ibh:
921 return err;
922}
923
924static void nilfs_fill_in_file_bmap(struct inode *ifile,
925 struct nilfs_inode_info *ii)
926
927{
928 struct buffer_head *ibh;
929 struct nilfs_inode *raw_inode;
930
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);
938 }
939}
940
941static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
942{
943 struct nilfs_inode_info *ii;
944
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);
948 }
949}
950
951static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
952 struct the_nilfs *nilfs)
953{
954 struct buffer_head *bh_sr;
955 struct nilfs_super_root *raw_sr;
956 unsigned int isz, srsz;
957
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);
962
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;
968
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);
976}
977
978static void nilfs_redirty_inodes(struct list_head *head)
979{
980 struct nilfs_inode_info *ii;
981
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);
985 }
986}
987
988static void nilfs_drop_collected_inodes(struct list_head *head)
989{
990 struct nilfs_inode_info *ii;
991
992 list_for_each_entry(ii, head, i_dirty) {
993 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
994 continue;
995
996 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
997 set_bit(NILFS_I_UPDATED, &ii->i_state);
998 }
999}
1000
1001static 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 *))
1007{
1008 struct buffer_head *bh, *n;
1009 int err = 0;
1010
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;
1018 }
1019 return 0;
1020 }
1021
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);
1028 }
1029 return err;
1030}
1031
1032static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1033{
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);
1037}
1038
1039static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1040 struct inode *inode,
1041 const struct nilfs_sc_operations *sc_ops)
1042{
1043 LIST_HEAD(data_buffers);
1044 LIST_HEAD(node_buffers);
1045 int err;
1046
1047 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1048 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1049
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;
1058 }
1059 }
1060 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1061
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;
1070 }
1071 sci->sc_stage.flags |= NILFS_CF_NODE;
1072 }
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;
1078
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;
1084
1085 nilfs_segctor_end_finfo(sci, inode);
1086 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1087
1088 break_or_fail:
1089 return err;
1090}
1091
1092static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1093 struct inode *inode)
1094{
1095 LIST_HEAD(data_buffers);
1096 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1097 int err;
1098
1099 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1100 sci->sc_dsync_start,
1101 sci->sc_dsync_end);
1102
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 */
1109 }
1110 return err;
1111}
1112
1113static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1114{
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;
1120
1121 switch (nilfs_sc_cstage_get(sci)) {
1122 case NILFS_ST_INIT:
1123 /* Pre-processes */
1124 sci->sc_stage.flags = 0;
1125
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;
1132 }
1133 }
1134
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;
1140 }
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;
1157 }
1158 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1159 }
1160 sci->sc_stage.gc_inode_ptr = NULL;
1161 }
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);
1169
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;
1178 }
1179 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1180 /* XXX: required ? */
1181 }
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;
1186 }
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;
1215 }
1216 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1217
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;
1232 }
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;
1240 }
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;
1251
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();
1262 }
1263
1264 break_or_fail:
1265 return err;
1266}
1267
1268/**
1269 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1270 * @sci: nilfs_sc_info
1271 * @nilfs: nilfs object
1272 */
1273static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1274 struct the_nilfs *nilfs)
1275{
1276 struct nilfs_segment_buffer *segbuf, *prev;
1277 __u64 nextnum;
1278 int err, alloc = 0;
1279
1280 segbuf = nilfs_segbuf_new(sci->sc_super);
1281 if (unlikely(!segbuf))
1282 return -ENOMEM;
1283
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);
1290 }
1291
1292 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1293 nextnum = nilfs->ns_nextnum;
1294
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;
1304
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++;
1309 }
1310 }
1311
1312 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1313 if (err)
1314 goto failed;
1315
1316 if (alloc) {
1317 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1318 if (err)
1319 goto failed;
1320 }
1321 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1322
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;
1327
1328 failed:
1329 nilfs_segbuf_free(segbuf);
1330 return err;
1331}
1332
1333static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1334 struct the_nilfs *nilfs, int nadd)
1335{
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;
1341
1342 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1343 /*
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.
1348 */
1349 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1350 if (unlikely(err))
1351 return err;
1352
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;
1359
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;
1363
1364 /* allocate the next next full segment */
1365 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1366 if (unlikely(err))
1367 goto failed_segbuf;
1368
1369 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1370 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1371
1372 list_add_tail(&segbuf->sb_list, &list);
1373 prev = segbuf;
1374 }
1375 list_splice_tail(&list, &sci->sc_segbufs);
1376 return 0;
1377
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 */
1384 }
1385 nilfs_destroy_logs(&list);
1386 return err;
1387}
1388
1389static void nilfs_free_incomplete_logs(struct list_head *logs,
1390 struct the_nilfs *nilfs)
1391{
1392 struct nilfs_segment_buffer *segbuf, *prev;
1393 struct inode *sufile = nilfs->ns_sufile;
1394 int ret;
1395
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 */
1400 }
1401 if (atomic_read(&segbuf->sb_err)) {
1402 /* Case 1: The first segment failed */
1403 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1404 /*
1405 * Case 1a: Partial segment appended into an existing
1406 * segment
1407 */
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);
1412 }
1413
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 */
1419 }
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;
1425 }
1426}
1427
1428static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1429 struct inode *sufile)
1430{
1431 struct nilfs_segment_buffer *segbuf;
1432 unsigned long live_blocks;
1433 int ret;
1434
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 */
1442 }
1443}
1444
1445static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1446{
1447 struct nilfs_segment_buffer *segbuf;
1448 int ret;
1449
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 */
1455
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 */
1460 }
1461}
1462
1463static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1464 struct nilfs_segment_buffer *last,
1465 struct inode *sufile)
1466{
1467 struct nilfs_segment_buffer *segbuf = last;
1468 int ret;
1469
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);
1474 }
1475 nilfs_truncate_logs(&sci->sc_segbufs, last);
1476}
1477
1478
1479static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1480 struct the_nilfs *nilfs, int mode)
1481{
1482 struct nilfs_cstage prev_stage = sci->sc_stage;
1483 int err, nadd = 1;
1484
1485 /* Collection retry loop */
1486 for (;;) {
1487 sci->sc_nblk_this_inc = 0;
1488 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1489
1490 err = nilfs_segctor_reset_segment_buffer(sci);
1491 if (unlikely(err))
1492 goto failed;
1493
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;
1498
1499 if (unlikely(err != -E2BIG))
1500 goto failed;
1501
1502 /* The current segment is filled up */
1503 if (mode != SC_LSEG_SR ||
1504 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1505 break;
1506
1507 nilfs_clear_logs(&sci->sc_segbufs);
1508
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;
1516 }
1517
1518 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1519 if (unlikely(err))
1520 return err;
1521
1522 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1523 sci->sc_stage = prev_stage;
1524 }
1525 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1526 return 0;
1527
1528 failed:
1529 return err;
1530}
1531
1532static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1533 struct buffer_head *new_bh)
1534{
1535 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1536
1537 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1538 /* The caller must release old_bh */
1539}
1540
1541static int
1542nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1543 struct nilfs_segment_buffer *segbuf,
1544 int mode)
1545{
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;
1557
1558 if (!nfinfo)
1559 goto out;
1560
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);
1564
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);
1574
1575 inode = bh->b_page->mapping->host;
1576
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;
1583 }
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;
1593
1594 if (ndatablk > 0)
1595 sc_op->write_data_binfo(sci, &ssp, &binfo);
1596 else
1597 sc_op->write_node_binfo(sci, &ssp, &binfo);
1598
1599 blocknr++;
1600 if (--nblocks == 0) {
1601 finfo = NULL;
1602 if (--nfinfo == 0)
1603 break;
1604 } else if (ndatablk > 0)
1605 ndatablk--;
1606 }
1607 out:
1608 return 0;
1609
1610 failed_bmap:
1611 return err;
1612}
1613
1614static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1615{
1616 struct nilfs_segment_buffer *segbuf;
1617 int err;
1618
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);
1624 }
1625 return 0;
1626}
1627
1628static void nilfs_begin_page_io(struct page *page)
1629{
1630 if (!page || PageWriteback(page))
1631 /*
1632 * For split b-tree node pages, this function may be called
1633 * twice. We ignore the 2nd or later calls by this check.
1634 */
1635 return;
1636
1637 lock_page(page);
1638 clear_page_dirty_for_io(page);
1639 set_page_writeback(page);
1640 unlock_page(page);
1641}
1642
1643static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1644{
1645 struct nilfs_segment_buffer *segbuf;
1646 struct page *bd_page = NULL, *fs_page = NULL;
1647
1648 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1649 struct buffer_head *bh;
1650
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);
1659 }
1660 bd_page = bh->b_page;
1661 }
1662 }
1663
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;
1674 }
1675 break;
1676 }
1677 if (bh->b_page != fs_page) {
1678 nilfs_begin_page_io(fs_page);
1679 fs_page = bh->b_page;
1680 }
1681 }
1682 }
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);
1688 }
1689 nilfs_begin_page_io(fs_page);
1690}
1691
1692static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1693 struct the_nilfs *nilfs)
1694{
1695 int ret;
1696
1697 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1698 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1699 return ret;
1700}
1701
1702static void nilfs_end_page_io(struct page *page, int err)
1703{
1704 if (!page)
1705 return;
1706
1707 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1708 /*
1709 * For b-tree node pages, this function may be called twice
1710 * or more because they might be split in a segment.
1711 */
1712 if (PageDirty(page)) {
1713 /*
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.
1719 */
1720 lock_page(page);
1721 if (nilfs_page_buffers_clean(page))
1722 __nilfs_clear_page_dirty(page);
1723 unlock_page(page);
1724 }
1725 return;
1726 }
1727
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);
1735 }
1736
1737 end_page_writeback(page);
1738}
1739
1740static void nilfs_abort_logs(struct list_head *logs, int err)
1741{
1742 struct nilfs_segment_buffer *segbuf;
1743 struct page *bd_page = NULL, *fs_page = NULL;
1744 struct buffer_head *bh;
1745
1746 if (list_empty(logs))
1747 return;
1748
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;
1756 }
1757 }
1758
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;
1766 }
1767 break;
1768 }
1769 if (bh->b_page != fs_page) {
1770 nilfs_end_page_io(fs_page, err);
1771 fs_page = bh->b_page;
1772 }
1773 }
1774 }
1775 if (bd_page)
1776 end_page_writeback(bd_page);
1777
1778 nilfs_end_page_io(fs_page, err);
1779}
1780
1781static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1782 struct the_nilfs *nilfs, int err)
1783{
1784 LIST_HEAD(logs);
1785 int ret;
1786
1787 list_splice_tail_init(&sci->sc_write_logs, &logs);
1788 ret = nilfs_wait_on_logs(&logs);
1789 nilfs_abort_logs(&logs, ret ? : err);
1790
1791 list_splice_tail_init(&sci->sc_segbufs, &logs);
1792 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1793 nilfs_free_incomplete_logs(&logs, nilfs);
1794
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 */
1801 }
1802
1803 nilfs_destroy_logs(&logs);
1804}
1805
1806static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1807 struct nilfs_segment_buffer *segbuf)
1808{
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;
1815}
1816
1817static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1818{
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;
1823
1824 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1825 struct buffer_head *bh;
1826
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;
1835 }
1836 }
1837 /*
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).
1843 *
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.
1847 */
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));
1855
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;
1861 }
1862 update_sr = true;
1863 break;
1864 }
1865 if (bh->b_page != fs_page) {
1866 nilfs_end_page_io(fs_page, 0);
1867 fs_page = bh->b_page;
1868 }
1869 }
1870
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;
1875 }
1876 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1877 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1878 }
1879 }
1880 /*
1881 * Since pages may continue over multiple segment buffers,
1882 * end of the last page must be checked outside of the loop.
1883 */
1884 if (bd_page)
1885 end_page_writeback(bd_page);
1886
1887 nilfs_end_page_io(fs_page, 0);
1888
1889 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1890
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;
1895
1896 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1897
1898 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1899 nilfs_set_next_segment(nilfs, segbuf);
1900
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++);
1905
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);
1912}
1913
1914static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1915{
1916 int ret;
1917
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);
1922 }
1923 return ret;
1924}
1925
1926static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1927 struct the_nilfs *nilfs)
1928{
1929 struct nilfs_inode_info *ii, *n;
1930 struct inode *ifile = sci->sc_root->ifile;
1931
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;
1938
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;
1947 }
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;
1954 }
1955
1956 // Always redirty the buffer to avoid race condition
1957 mark_buffer_dirty(ii->i_bh);
1958 nilfs_mdt_mark_dirty(ifile);
1959
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);
1963 }
1964 spin_unlock(&nilfs->ns_inode_lock);
1965
1966 return 0;
1967}
1968
1969static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1970 struct the_nilfs *nilfs)
1971{
1972 struct nilfs_inode_info *ii, *n;
1973 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
1974 int defer_iput = false;
1975
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;
1981
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) {
1987 /*
1988 * Defer calling iput() to avoid deadlocks if
1989 * i_nlink == 0 or mount is not yet finished.
1990 */
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);
1997 }
1998 }
1999 spin_unlock(&nilfs->ns_inode_lock);
2000
2001 if (defer_iput)
2002 schedule_work(&sci->sc_iput_work);
2003}
2004
2005/*
2006 * Main procedure of segment constructor
2007 */
2008static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2009{
2010 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2011 int err;
2012
2013 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2014 sci->sc_cno = nilfs->ns_cno;
2015
2016 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2017 if (unlikely(err))
2018 goto out;
2019
2020 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2021 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2022
2023 if (nilfs_segctor_clean(sci))
2024 goto out;
2025
2026 do {
2027 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2028
2029 err = nilfs_segctor_begin_construction(sci, nilfs);
2030 if (unlikely(err))
2031 goto out;
2032
2033 /* Update time stamp */
2034 sci->sc_seg_ctime = ktime_get_real_seconds();
2035
2036 err = nilfs_segctor_collect(sci, nilfs, mode);
2037 if (unlikely(err))
2038 goto failed;
2039
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;
2045 }
2046
2047 err = nilfs_segctor_assign(sci, mode);
2048 if (unlikely(err))
2049 goto failed;
2050
2051 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2052 nilfs_segctor_fill_in_file_bmap(sci);
2053
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;
2059
2060 nilfs_segctor_fill_in_super_root(sci, nilfs);
2061 }
2062 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2063
2064 /* Write partial segments */
2065 nilfs_segctor_prepare_write(sci);
2066
2067 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2068 nilfs->ns_crc_seed);
2069
2070 err = nilfs_segctor_write(sci, nilfs);
2071 if (unlikely(err))
2072 goto failed_to_write;
2073
2074 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2075 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2076 /*
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.
2082 */
2083 err = nilfs_segctor_wait(sci);
2084 if (err)
2085 goto failed_to_write;
2086 }
2087 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2088
2089 out:
2090 nilfs_segctor_drop_written_files(sci, nilfs);
2091 return err;
2092
2093 failed_to_write:
2094 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2095 nilfs_redirty_inodes(&sci->sc_dirty_files);
2096
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;
2102}
2103
2104/**
2105 * nilfs_segctor_start_timer - set timer of background write
2106 * @sci: nilfs_sc_info
2107 *
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.
2111 */
2112static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2113{
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;
2119 }
2120 spin_unlock(&sci->sc_state_lock);
2121}
2122
2123static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2124{
2125 spin_lock(&sci->sc_state_lock);
2126 if (!(sci->sc_flush_request & BIT(bn))) {
2127 unsigned long prev_req = sci->sc_flush_request;
2128
2129 sci->sc_flush_request |= BIT(bn);
2130 if (!prev_req)
2131 wake_up(&sci->sc_wait_daemon);
2132 }
2133 spin_unlock(&sci->sc_state_lock);
2134}
2135
2136/**
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.
2140 */
2141void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2142{
2143 struct the_nilfs *nilfs = sb->s_fs_info;
2144 struct nilfs_sc_info *sci = nilfs->ns_writer;
2145
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 */
2150}
2151
2152struct nilfs_segctor_wait_request {
2153 wait_queue_entry_t wq;
2154 __u32 seq;
2155 int err;
2156 atomic_t done;
2157};
2158
2159static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2160{
2161 struct nilfs_segctor_wait_request wait_req;
2162 int err = 0;
2163
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);
2170
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);
2175
2176 for (;;) {
2177 if (atomic_read(&wait_req.done)) {
2178 err = wait_req.err;
2179 break;
2180 }
2181 if (!signal_pending(current)) {
2182 schedule();
2183 continue;
2184 }
2185 err = -ERESTARTSYS;
2186 break;
2187 }
2188 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2189 return err;
2190}
2191
2192static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2193{
2194 struct nilfs_segctor_wait_request *wrq, *n;
2195 unsigned long flags;
2196
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);
2203 }
2204 if (atomic_read(&wrq->done)) {
2205 wrq->wq.func(&wrq->wq,
2206 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2207 0, NULL);
2208 }
2209 }
2210 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2211}
2212
2213/**
2214 * nilfs_construct_segment - construct a logical segment
2215 * @sb: super block
2216 *
2217 * Return Value: On success, 0 is retured. On errors, one of the following
2218 * negative error code is returned.
2219 *
2220 * %-EROFS - Read only filesystem.
2221 *
2222 * %-EIO - I/O error
2223 *
2224 * %-ENOSPC - No space left on device (only in a panic state).
2225 *
2226 * %-ERESTARTSYS - Interrupted.
2227 *
2228 * %-ENOMEM - Insufficient memory available.
2229 */
2230int nilfs_construct_segment(struct super_block *sb)
2231{
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;
2236
2237 if (!sci)
2238 return -EROFS;
2239
2240 /* A call inside transactions causes a deadlock. */
2241 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2242
2243 err = nilfs_segctor_sync(sci);
2244 return err;
2245}
2246
2247/**
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)
2253 *
2254 * Return Value: On success, 0 is retured. On errors, one of the following
2255 * negative error code is returned.
2256 *
2257 * %-EROFS - Read only filesystem.
2258 *
2259 * %-EIO - I/O error
2260 *
2261 * %-ENOSPC - No space left on device (only in a panic state).
2262 *
2263 * %-ERESTARTSYS - Interrupted.
2264 *
2265 * %-ENOMEM - Insufficient memory available.
2266 */
2267int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2268 loff_t start, loff_t end)
2269{
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;
2275
2276 if (!sci)
2277 return -EROFS;
2278
2279 nilfs_transaction_lock(sb, &ti, 0);
2280
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;
2289 }
2290
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;
2297 }
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;
2302
2303 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2304 if (!err)
2305 nilfs->ns_flushed_device = 0;
2306
2307 nilfs_transaction_unlock(sb);
2308 return err;
2309}
2310
2311#define FLUSH_FILE_BIT (0x1) /* data file only */
2312#define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2313
2314/**
2315 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2316 * @sci: segment constructor object
2317 */
2318static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2319{
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);
2324}
2325
2326/**
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
2331 */
2332static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2333{
2334 /* Clear requests (even when the construction failed) */
2335 spin_lock(&sci->sc_state_lock);
2336
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;
2347
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);
2352 }
2353 spin_unlock(&sci->sc_state_lock);
2354}
2355
2356/**
2357 * nilfs_segctor_construct - form logs and write them to disk
2358 * @sci: segment constructor object
2359 * @mode: mode of log forming
2360 */
2361static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2362{
2363 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2364 struct nilfs_super_block **sbp;
2365 int err = 0;
2366
2367 nilfs_segctor_accept(sci);
2368
2369 if (nilfs_discontinued(nilfs))
2370 mode = SC_LSEG_SR;
2371 if (!nilfs_segctor_confirm(sci))
2372 err = nilfs_segctor_do_construct(sci, mode);
2373
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);
2387 }
2388 up_write(&nilfs->ns_sem);
2389 }
2390 }
2391
2392 nilfs_segctor_notify(sci, mode, err);
2393 return err;
2394}
2395
2396static void nilfs_construction_timeout(struct timer_list *t)
2397{
2398 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2399
2400 wake_up_process(sci->sc_timer_task);
2401}
2402
2403static void
2404nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2405{
2406 struct nilfs_inode_info *ii, *n;
2407
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);
2415 }
2416}
2417
2418int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2419 void **kbufs)
2420{
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;
2425
2426 if (unlikely(!sci))
2427 return -EROFS;
2428
2429 nilfs_transaction_lock(sb, &ti, 1);
2430
2431 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2432 if (unlikely(err))
2433 goto out_unlock;
2434
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;
2439 }
2440
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);
2444
2445 for (;;) {
2446 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2447 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2448
2449 if (likely(!err))
2450 break;
2451
2452 nilfs_msg(sb, KERN_WARNING, "error %d cleaning segments", err);
2453 set_current_state(TASK_INTERRUPTIBLE);
2454 schedule_timeout(sci->sc_interval);
2455 }
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);
2464 }
2465 }
2466
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;
2473}
2474
2475static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2476{
2477 struct nilfs_transaction_info ti;
2478
2479 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2480 nilfs_segctor_construct(sci, mode);
2481
2482 /*
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.
2486 */
2487 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2488 nilfs_segctor_start_timer(sci);
2489
2490 nilfs_transaction_unlock(sci->sc_super);
2491}
2492
2493static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2494{
2495 int mode = 0;
2496
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);
2501
2502 if (mode) {
2503 nilfs_segctor_do_construct(sci, mode);
2504
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);
2509 }
2510 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2511}
2512
2513static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2514{
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;
2521 }
2522 return SC_LSEG_SR;
2523}
2524
2525/**
2526 * nilfs_segctor_thread - main loop of the segment constructor thread.
2527 * @arg: pointer to a struct nilfs_sc_info.
2528 *
2529 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2530 * to execute segment constructions.
2531 */
2532static int nilfs_segctor_thread(void *arg)
2533{
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;
2537
2538 sci->sc_timer_task = current;
2539
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);
2546
2547 spin_lock(&sci->sc_state_lock);
2548 loop:
2549 for (;;) {
2550 int mode;
2551
2552 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2553 goto end_thread;
2554
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;
2561
2562 spin_unlock(&sci->sc_state_lock);
2563 nilfs_segctor_thread_construct(sci, mode);
2564 spin_lock(&sci->sc_state_lock);
2565 timeout = 0;
2566 }
2567
2568
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;
2576
2577 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2578 TASK_INTERRUPTIBLE);
2579
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);
2587
2588 if (should_sleep) {
2589 spin_unlock(&sci->sc_state_lock);
2590 schedule();
2591 spin_lock(&sci->sc_state_lock);
2592 }
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));
2596
2597 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2598 set_nilfs_discontinued(nilfs);
2599 }
2600 goto loop;
2601
2602 end_thread:
2603 spin_unlock(&sci->sc_state_lock);
2604
2605 /* end sync. */
2606 sci->sc_task = NULL;
2607 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2608 return 0;
2609}
2610
2611static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2612{
2613 struct task_struct *t;
2614
2615 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2616 if (IS_ERR(t)) {
2617 int err = PTR_ERR(t);
2618
2619 nilfs_msg(sci->sc_super, KERN_ERR,
2620 "error %d creating segctord thread", err);
2621 return err;
2622 }
2623 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2624 return 0;
2625}
2626
2627static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2628 __acquires(&sci->sc_state_lock)
2629 __releases(&sci->sc_state_lock)
2630{
2631 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2632
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);
2638 }
2639}
2640
2641/*
2642 * Setup & clean-up functions
2643 */
2644static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2645 struct nilfs_root *root)
2646{
2647 struct the_nilfs *nilfs = sb->s_fs_info;
2648 struct nilfs_sc_info *sci;
2649
2650 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2651 if (!sci)
2652 return NULL;
2653
2654 sci->sc_super = sb;
2655
2656 nilfs_get_root(root);
2657 sci->sc_root = root;
2658
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);
2670
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;
2674
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;
2680}
2681
2682static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2683{
2684 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2685
2686 /*
2687 * The segctord thread was stopped and its timer was removed.
2688 * But some tasks remain.
2689 */
2690 do {
2691 struct nilfs_transaction_info ti;
2692
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);
2696
2697 flush_work(&sci->sc_iput_work);
2698
2699 } while (ret && retrycount-- > 0);
2700}
2701
2702/**
2703 * nilfs_segctor_destroy - destroy the segment constructor.
2704 * @sci: nilfs_sc_info
2705 *
2706 * nilfs_segctor_destroy() kills the segctord thread and frees
2707 * the nilfs_sc_info struct.
2708 * Caller must hold the segment semaphore.
2709 */
2710static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2711{
2712 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2713 int flag;
2714
2715 up_write(&nilfs->ns_segctor_sem);
2716
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);
2722
2723 if (flush_work(&sci->sc_iput_work))
2724 flag = true;
2725
2726 if (flag || !nilfs_segctor_confirm(sci))
2727 nilfs_segctor_write_out(sci);
2728
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);
2733 }
2734
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);
2739 }
2740
2741 WARN_ON(!list_empty(&sci->sc_segbufs));
2742 WARN_ON(!list_empty(&sci->sc_write_logs));
2743
2744 nilfs_put_root(sci->sc_root);
2745
2746 down_write(&nilfs->ns_segctor_sem);
2747
2748 del_timer_sync(&sci->sc_timer);
2749 kfree(sci);
2750}
2751
2752/**
2753 * nilfs_attach_log_writer - attach log writer
2754 * @sb: super block instance
2755 * @root: root object of the current filesystem tree
2756 *
2757 * This allocates a log writer object, initializes it, and starts the
2758 * log writer.
2759 *
2760 * Return Value: On success, 0 is returned. On error, one of the following
2761 * negative error code is returned.
2762 *
2763 * %-ENOMEM - Insufficient memory available.
2764 */
2765int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2766{
2767 struct the_nilfs *nilfs = sb->s_fs_info;
2768 int err;
2769
2770 if (nilfs->ns_writer) {
2771 /*
2772 * This happens if the filesystem was remounted
2773 * read/write after nilfs_error degenerated it into a
2774 * read-only mount.
2775 */
2776 nilfs_detach_log_writer(sb);
2777 }
2778
2779 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2780 if (!nilfs->ns_writer)
2781 return -ENOMEM;
2782
2783 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2784 if (err) {
2785 kfree(nilfs->ns_writer);
2786 nilfs->ns_writer = NULL;
2787 }
2788 return err;
2789}
2790
2791/**
2792 * nilfs_detach_log_writer - destroy log writer
2793 * @sb: super block instance
2794 *
2795 * This kills log writer daemon, frees the log writer object, and
2796 * destroys list of dirty files.
2797 */
2798void nilfs_detach_log_writer(struct super_block *sb)
2799{
2800 struct the_nilfs *nilfs = sb->s_fs_info;
2801 LIST_HEAD(garbage_list);
2802
2803 down_write(&nilfs->ns_segctor_sem);
2804 if (nilfs->ns_writer) {
2805 nilfs_segctor_destroy(nilfs->ns_writer);
2806 nilfs->ns_writer = NULL;
2807 }
2808
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");
2815 }
2816 spin_unlock(&nilfs->ns_inode_lock);
2817 up_write(&nilfs->ns_segctor_sem);
2818
2819 nilfs_dispose_list(nilfs, &garbage_list, 1);
2820}
1/*
2 * segment.c - NILFS segment constructor.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
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.
10 *
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.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
21 *
22 */
23
24#include <linux/pagemap.h>
25#include <linux/buffer_head.h>
26#include <linux/writeback.h>
27#include <linux/bitops.h>
28#include <linux/bio.h>
29#include <linux/completion.h>
30#include <linux/blkdev.h>
31#include <linux/backing-dev.h>
32#include <linux/freezer.h>
33#include <linux/kthread.h>
34#include <linux/crc32.h>
35#include <linux/pagevec.h>
36#include <linux/slab.h>
37#include "nilfs.h"
38#include "btnode.h"
39#include "page.h"
40#include "segment.h"
41#include "sufile.h"
42#include "cpfile.h"
43#include "ifile.h"
44#include "segbuf.h"
45
46
47/*
48 * Segment constructor
49 */
50#define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
51
52#define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments
53 appended in collection retry loop */
54
55/* Construction mode */
56enum {
57 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
58 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make
59 a logical segment without a super root */
60 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without
61 creating a checkpoint */
62 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without
63 a checkpoint */
64};
65
66/* Stage numbers of dirty block collection */
67enum {
68 NILFS_ST_INIT = 0,
69 NILFS_ST_GC, /* Collecting dirty blocks for GC */
70 NILFS_ST_FILE,
71 NILFS_ST_IFILE,
72 NILFS_ST_CPFILE,
73 NILFS_ST_SUFILE,
74 NILFS_ST_DAT,
75 NILFS_ST_SR, /* Super root */
76 NILFS_ST_DSYNC, /* Data sync blocks */
77 NILFS_ST_DONE,
78};
79
80#define CREATE_TRACE_POINTS
81#include <trace/events/nilfs2.h>
82
83/*
84 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
85 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
86 * the variable must use them because transition of stage count must involve
87 * trace events (trace_nilfs2_collection_stage_transition).
88 *
89 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
90 * produce tracepoint events. It is provided just for making the intention
91 * clear.
92 */
93static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
94{
95 sci->sc_stage.scnt++;
96 trace_nilfs2_collection_stage_transition(sci);
97}
98
99static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
100{
101 sci->sc_stage.scnt = next_scnt;
102 trace_nilfs2_collection_stage_transition(sci);
103}
104
105static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
106{
107 return sci->sc_stage.scnt;
108}
109
110/* State flags of collection */
111#define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
112#define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
113#define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
114#define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
115
116/* Operations depending on the construction mode and file type */
117struct nilfs_sc_operations {
118 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
119 struct inode *);
120 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
121 struct inode *);
122 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
123 struct inode *);
124 void (*write_data_binfo)(struct nilfs_sc_info *,
125 struct nilfs_segsum_pointer *,
126 union nilfs_binfo *);
127 void (*write_node_binfo)(struct nilfs_sc_info *,
128 struct nilfs_segsum_pointer *,
129 union nilfs_binfo *);
130};
131
132/*
133 * Other definitions
134 */
135static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
136static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
137static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
138static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
139
140#define nilfs_cnt32_gt(a, b) \
141 (typecheck(__u32, a) && typecheck(__u32, b) && \
142 ((__s32)(b) - (__s32)(a) < 0))
143#define nilfs_cnt32_ge(a, b) \
144 (typecheck(__u32, a) && typecheck(__u32, b) && \
145 ((__s32)(a) - (__s32)(b) >= 0))
146#define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
147#define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
148
149static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
150{
151 struct nilfs_transaction_info *cur_ti = current->journal_info;
152 void *save = NULL;
153
154 if (cur_ti) {
155 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
156 return ++cur_ti->ti_count;
157 else {
158 /*
159 * If journal_info field is occupied by other FS,
160 * it is saved and will be restored on
161 * nilfs_transaction_commit().
162 */
163 printk(KERN_WARNING
164 "NILFS warning: journal info from a different "
165 "FS\n");
166 save = current->journal_info;
167 }
168 }
169 if (!ti) {
170 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
171 if (!ti)
172 return -ENOMEM;
173 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
174 } else {
175 ti->ti_flags = 0;
176 }
177 ti->ti_count = 0;
178 ti->ti_save = save;
179 ti->ti_magic = NILFS_TI_MAGIC;
180 current->journal_info = ti;
181 return 0;
182}
183
184/**
185 * nilfs_transaction_begin - start indivisible file operations.
186 * @sb: super block
187 * @ti: nilfs_transaction_info
188 * @vacancy_check: flags for vacancy rate checks
189 *
190 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
191 * the segment semaphore, to make a segment construction and write tasks
192 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
193 * The region enclosed by these two functions can be nested. To avoid a
194 * deadlock, the semaphore is only acquired or released in the outermost call.
195 *
196 * This function allocates a nilfs_transaction_info struct to keep context
197 * information on it. It is initialized and hooked onto the current task in
198 * the outermost call. If a pre-allocated struct is given to @ti, it is used
199 * instead; otherwise a new struct is assigned from a slab.
200 *
201 * When @vacancy_check flag is set, this function will check the amount of
202 * free space, and will wait for the GC to reclaim disk space if low capacity.
203 *
204 * Return Value: On success, 0 is returned. On error, one of the following
205 * negative error code is returned.
206 *
207 * %-ENOMEM - Insufficient memory available.
208 *
209 * %-ENOSPC - No space left on device
210 */
211int nilfs_transaction_begin(struct super_block *sb,
212 struct nilfs_transaction_info *ti,
213 int vacancy_check)
214{
215 struct the_nilfs *nilfs;
216 int ret = nilfs_prepare_segment_lock(ti);
217 struct nilfs_transaction_info *trace_ti;
218
219 if (unlikely(ret < 0))
220 return ret;
221 if (ret > 0) {
222 trace_ti = current->journal_info;
223
224 trace_nilfs2_transaction_transition(sb, trace_ti,
225 trace_ti->ti_count, trace_ti->ti_flags,
226 TRACE_NILFS2_TRANSACTION_BEGIN);
227 return 0;
228 }
229
230 sb_start_intwrite(sb);
231
232 nilfs = sb->s_fs_info;
233 down_read(&nilfs->ns_segctor_sem);
234 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
235 up_read(&nilfs->ns_segctor_sem);
236 ret = -ENOSPC;
237 goto failed;
238 }
239
240 trace_ti = current->journal_info;
241 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
242 trace_ti->ti_flags,
243 TRACE_NILFS2_TRANSACTION_BEGIN);
244 return 0;
245
246 failed:
247 ti = current->journal_info;
248 current->journal_info = ti->ti_save;
249 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
250 kmem_cache_free(nilfs_transaction_cachep, ti);
251 sb_end_intwrite(sb);
252 return ret;
253}
254
255/**
256 * nilfs_transaction_commit - commit indivisible file operations.
257 * @sb: super block
258 *
259 * nilfs_transaction_commit() releases the read semaphore which is
260 * acquired by nilfs_transaction_begin(). This is only performed
261 * in outermost call of this function. If a commit flag is set,
262 * nilfs_transaction_commit() sets a timer to start the segment
263 * constructor. If a sync flag is set, it starts construction
264 * directly.
265 */
266int nilfs_transaction_commit(struct super_block *sb)
267{
268 struct nilfs_transaction_info *ti = current->journal_info;
269 struct the_nilfs *nilfs = sb->s_fs_info;
270 int err = 0;
271
272 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
273 ti->ti_flags |= NILFS_TI_COMMIT;
274 if (ti->ti_count > 0) {
275 ti->ti_count--;
276 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
277 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
278 return 0;
279 }
280 if (nilfs->ns_writer) {
281 struct nilfs_sc_info *sci = nilfs->ns_writer;
282
283 if (ti->ti_flags & NILFS_TI_COMMIT)
284 nilfs_segctor_start_timer(sci);
285 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
286 nilfs_segctor_do_flush(sci, 0);
287 }
288 up_read(&nilfs->ns_segctor_sem);
289 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
290 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
291
292 current->journal_info = ti->ti_save;
293
294 if (ti->ti_flags & NILFS_TI_SYNC)
295 err = nilfs_construct_segment(sb);
296 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
297 kmem_cache_free(nilfs_transaction_cachep, ti);
298 sb_end_intwrite(sb);
299 return err;
300}
301
302void nilfs_transaction_abort(struct super_block *sb)
303{
304 struct nilfs_transaction_info *ti = current->journal_info;
305 struct the_nilfs *nilfs = sb->s_fs_info;
306
307 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
308 if (ti->ti_count > 0) {
309 ti->ti_count--;
310 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
311 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
312 return;
313 }
314 up_read(&nilfs->ns_segctor_sem);
315
316 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
317 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
318
319 current->journal_info = ti->ti_save;
320 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
321 kmem_cache_free(nilfs_transaction_cachep, ti);
322 sb_end_intwrite(sb);
323}
324
325void nilfs_relax_pressure_in_lock(struct super_block *sb)
326{
327 struct the_nilfs *nilfs = sb->s_fs_info;
328 struct nilfs_sc_info *sci = nilfs->ns_writer;
329
330 if (!sci || !sci->sc_flush_request)
331 return;
332
333 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
334 up_read(&nilfs->ns_segctor_sem);
335
336 down_write(&nilfs->ns_segctor_sem);
337 if (sci->sc_flush_request &&
338 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
339 struct nilfs_transaction_info *ti = current->journal_info;
340
341 ti->ti_flags |= NILFS_TI_WRITER;
342 nilfs_segctor_do_immediate_flush(sci);
343 ti->ti_flags &= ~NILFS_TI_WRITER;
344 }
345 downgrade_write(&nilfs->ns_segctor_sem);
346}
347
348static void nilfs_transaction_lock(struct super_block *sb,
349 struct nilfs_transaction_info *ti,
350 int gcflag)
351{
352 struct nilfs_transaction_info *cur_ti = current->journal_info;
353 struct the_nilfs *nilfs = sb->s_fs_info;
354 struct nilfs_sc_info *sci = nilfs->ns_writer;
355
356 WARN_ON(cur_ti);
357 ti->ti_flags = NILFS_TI_WRITER;
358 ti->ti_count = 0;
359 ti->ti_save = cur_ti;
360 ti->ti_magic = NILFS_TI_MAGIC;
361 current->journal_info = ti;
362
363 for (;;) {
364 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
365 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
366
367 down_write(&nilfs->ns_segctor_sem);
368 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
369 break;
370
371 nilfs_segctor_do_immediate_flush(sci);
372
373 up_write(&nilfs->ns_segctor_sem);
374 yield();
375 }
376 if (gcflag)
377 ti->ti_flags |= NILFS_TI_GC;
378
379 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
380 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
381}
382
383static void nilfs_transaction_unlock(struct super_block *sb)
384{
385 struct nilfs_transaction_info *ti = current->journal_info;
386 struct the_nilfs *nilfs = sb->s_fs_info;
387
388 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
389 BUG_ON(ti->ti_count > 0);
390
391 up_write(&nilfs->ns_segctor_sem);
392 current->journal_info = ti->ti_save;
393
394 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
395 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
396}
397
398static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
399 struct nilfs_segsum_pointer *ssp,
400 unsigned bytes)
401{
402 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
403 unsigned blocksize = sci->sc_super->s_blocksize;
404 void *p;
405
406 if (unlikely(ssp->offset + bytes > blocksize)) {
407 ssp->offset = 0;
408 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
409 &segbuf->sb_segsum_buffers));
410 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
411 }
412 p = ssp->bh->b_data + ssp->offset;
413 ssp->offset += bytes;
414 return p;
415}
416
417/**
418 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
419 * @sci: nilfs_sc_info
420 */
421static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
422{
423 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
424 struct buffer_head *sumbh;
425 unsigned sumbytes;
426 unsigned flags = 0;
427 int err;
428
429 if (nilfs_doing_gc())
430 flags = NILFS_SS_GC;
431 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
432 if (unlikely(err))
433 return err;
434
435 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
436 sumbytes = segbuf->sb_sum.sumbytes;
437 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
438 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
439 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
440 return 0;
441}
442
443static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
444{
445 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
446 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
447 return -E2BIG; /* The current segment is filled up
448 (internal code) */
449 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
450 return nilfs_segctor_reset_segment_buffer(sci);
451}
452
453static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
454{
455 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
456 int err;
457
458 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
459 err = nilfs_segctor_feed_segment(sci);
460 if (err)
461 return err;
462 segbuf = sci->sc_curseg;
463 }
464 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
465 if (likely(!err))
466 segbuf->sb_sum.flags |= NILFS_SS_SR;
467 return err;
468}
469
470/*
471 * Functions for making segment summary and payloads
472 */
473static int nilfs_segctor_segsum_block_required(
474 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
475 unsigned binfo_size)
476{
477 unsigned blocksize = sci->sc_super->s_blocksize;
478 /* Size of finfo and binfo is enough small against blocksize */
479
480 return ssp->offset + binfo_size +
481 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
482 blocksize;
483}
484
485static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
486 struct inode *inode)
487{
488 sci->sc_curseg->sb_sum.nfinfo++;
489 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
490 nilfs_segctor_map_segsum_entry(
491 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
492
493 if (NILFS_I(inode)->i_root &&
494 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
495 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
496 /* skip finfo */
497}
498
499static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
500 struct inode *inode)
501{
502 struct nilfs_finfo *finfo;
503 struct nilfs_inode_info *ii;
504 struct nilfs_segment_buffer *segbuf;
505 __u64 cno;
506
507 if (sci->sc_blk_cnt == 0)
508 return;
509
510 ii = NILFS_I(inode);
511
512 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
513 cno = ii->i_cno;
514 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
515 cno = 0;
516 else
517 cno = sci->sc_cno;
518
519 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
520 sizeof(*finfo));
521 finfo->fi_ino = cpu_to_le64(inode->i_ino);
522 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
523 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
524 finfo->fi_cno = cpu_to_le64(cno);
525
526 segbuf = sci->sc_curseg;
527 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
528 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
529 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
530 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
531}
532
533static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
534 struct buffer_head *bh,
535 struct inode *inode,
536 unsigned binfo_size)
537{
538 struct nilfs_segment_buffer *segbuf;
539 int required, err = 0;
540
541 retry:
542 segbuf = sci->sc_curseg;
543 required = nilfs_segctor_segsum_block_required(
544 sci, &sci->sc_binfo_ptr, binfo_size);
545 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
546 nilfs_segctor_end_finfo(sci, inode);
547 err = nilfs_segctor_feed_segment(sci);
548 if (err)
549 return err;
550 goto retry;
551 }
552 if (unlikely(required)) {
553 err = nilfs_segbuf_extend_segsum(segbuf);
554 if (unlikely(err))
555 goto failed;
556 }
557 if (sci->sc_blk_cnt == 0)
558 nilfs_segctor_begin_finfo(sci, inode);
559
560 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
561 /* Substitution to vblocknr is delayed until update_blocknr() */
562 nilfs_segbuf_add_file_buffer(segbuf, bh);
563 sci->sc_blk_cnt++;
564 failed:
565 return err;
566}
567
568/*
569 * Callback functions that enumerate, mark, and collect dirty blocks
570 */
571static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
572 struct buffer_head *bh, struct inode *inode)
573{
574 int err;
575
576 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
577 if (err < 0)
578 return err;
579
580 err = nilfs_segctor_add_file_block(sci, bh, inode,
581 sizeof(struct nilfs_binfo_v));
582 if (!err)
583 sci->sc_datablk_cnt++;
584 return err;
585}
586
587static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
588 struct buffer_head *bh,
589 struct inode *inode)
590{
591 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
592}
593
594static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
595 struct buffer_head *bh,
596 struct inode *inode)
597{
598 WARN_ON(!buffer_dirty(bh));
599 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
600}
601
602static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
603 struct nilfs_segsum_pointer *ssp,
604 union nilfs_binfo *binfo)
605{
606 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
607 sci, ssp, sizeof(*binfo_v));
608 *binfo_v = binfo->bi_v;
609}
610
611static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
612 struct nilfs_segsum_pointer *ssp,
613 union nilfs_binfo *binfo)
614{
615 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
616 sci, ssp, sizeof(*vblocknr));
617 *vblocknr = binfo->bi_v.bi_vblocknr;
618}
619
620static struct nilfs_sc_operations nilfs_sc_file_ops = {
621 .collect_data = nilfs_collect_file_data,
622 .collect_node = nilfs_collect_file_node,
623 .collect_bmap = nilfs_collect_file_bmap,
624 .write_data_binfo = nilfs_write_file_data_binfo,
625 .write_node_binfo = nilfs_write_file_node_binfo,
626};
627
628static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
629 struct buffer_head *bh, struct inode *inode)
630{
631 int err;
632
633 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
634 if (err < 0)
635 return err;
636
637 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
638 if (!err)
639 sci->sc_datablk_cnt++;
640 return err;
641}
642
643static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
644 struct buffer_head *bh, struct inode *inode)
645{
646 WARN_ON(!buffer_dirty(bh));
647 return nilfs_segctor_add_file_block(sci, bh, inode,
648 sizeof(struct nilfs_binfo_dat));
649}
650
651static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
652 struct nilfs_segsum_pointer *ssp,
653 union nilfs_binfo *binfo)
654{
655 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
656 sizeof(*blkoff));
657 *blkoff = binfo->bi_dat.bi_blkoff;
658}
659
660static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
661 struct nilfs_segsum_pointer *ssp,
662 union nilfs_binfo *binfo)
663{
664 struct nilfs_binfo_dat *binfo_dat =
665 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
666 *binfo_dat = binfo->bi_dat;
667}
668
669static struct nilfs_sc_operations nilfs_sc_dat_ops = {
670 .collect_data = nilfs_collect_dat_data,
671 .collect_node = nilfs_collect_file_node,
672 .collect_bmap = nilfs_collect_dat_bmap,
673 .write_data_binfo = nilfs_write_dat_data_binfo,
674 .write_node_binfo = nilfs_write_dat_node_binfo,
675};
676
677static struct nilfs_sc_operations nilfs_sc_dsync_ops = {
678 .collect_data = nilfs_collect_file_data,
679 .collect_node = NULL,
680 .collect_bmap = NULL,
681 .write_data_binfo = nilfs_write_file_data_binfo,
682 .write_node_binfo = NULL,
683};
684
685static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
686 struct list_head *listp,
687 size_t nlimit,
688 loff_t start, loff_t end)
689{
690 struct address_space *mapping = inode->i_mapping;
691 struct pagevec pvec;
692 pgoff_t index = 0, last = ULONG_MAX;
693 size_t ndirties = 0;
694 int i;
695
696 if (unlikely(start != 0 || end != LLONG_MAX)) {
697 /*
698 * A valid range is given for sync-ing data pages. The
699 * range is rounded to per-page; extra dirty buffers
700 * may be included if blocksize < pagesize.
701 */
702 index = start >> PAGE_SHIFT;
703 last = end >> PAGE_SHIFT;
704 }
705 pagevec_init(&pvec, 0);
706 repeat:
707 if (unlikely(index > last) ||
708 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
709 min_t(pgoff_t, last - index,
710 PAGEVEC_SIZE - 1) + 1))
711 return ndirties;
712
713 for (i = 0; i < pagevec_count(&pvec); i++) {
714 struct buffer_head *bh, *head;
715 struct page *page = pvec.pages[i];
716
717 if (unlikely(page->index > last))
718 break;
719
720 lock_page(page);
721 if (!page_has_buffers(page))
722 create_empty_buffers(page, 1 << inode->i_blkbits, 0);
723 unlock_page(page);
724
725 bh = head = page_buffers(page);
726 do {
727 if (!buffer_dirty(bh) || buffer_async_write(bh))
728 continue;
729 get_bh(bh);
730 list_add_tail(&bh->b_assoc_buffers, listp);
731 ndirties++;
732 if (unlikely(ndirties >= nlimit)) {
733 pagevec_release(&pvec);
734 cond_resched();
735 return ndirties;
736 }
737 } while (bh = bh->b_this_page, bh != head);
738 }
739 pagevec_release(&pvec);
740 cond_resched();
741 goto repeat;
742}
743
744static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
745 struct list_head *listp)
746{
747 struct nilfs_inode_info *ii = NILFS_I(inode);
748 struct address_space *mapping = &ii->i_btnode_cache;
749 struct pagevec pvec;
750 struct buffer_head *bh, *head;
751 unsigned int i;
752 pgoff_t index = 0;
753
754 pagevec_init(&pvec, 0);
755
756 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
757 PAGEVEC_SIZE)) {
758 for (i = 0; i < pagevec_count(&pvec); i++) {
759 bh = head = page_buffers(pvec.pages[i]);
760 do {
761 if (buffer_dirty(bh) &&
762 !buffer_async_write(bh)) {
763 get_bh(bh);
764 list_add_tail(&bh->b_assoc_buffers,
765 listp);
766 }
767 bh = bh->b_this_page;
768 } while (bh != head);
769 }
770 pagevec_release(&pvec);
771 cond_resched();
772 }
773}
774
775static void nilfs_dispose_list(struct the_nilfs *nilfs,
776 struct list_head *head, int force)
777{
778 struct nilfs_inode_info *ii, *n;
779 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
780 unsigned nv = 0;
781
782 while (!list_empty(head)) {
783 spin_lock(&nilfs->ns_inode_lock);
784 list_for_each_entry_safe(ii, n, head, i_dirty) {
785 list_del_init(&ii->i_dirty);
786 if (force) {
787 if (unlikely(ii->i_bh)) {
788 brelse(ii->i_bh);
789 ii->i_bh = NULL;
790 }
791 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
792 set_bit(NILFS_I_QUEUED, &ii->i_state);
793 list_add_tail(&ii->i_dirty,
794 &nilfs->ns_dirty_files);
795 continue;
796 }
797 ivec[nv++] = ii;
798 if (nv == SC_N_INODEVEC)
799 break;
800 }
801 spin_unlock(&nilfs->ns_inode_lock);
802
803 for (pii = ivec; nv > 0; pii++, nv--)
804 iput(&(*pii)->vfs_inode);
805 }
806}
807
808static void nilfs_iput_work_func(struct work_struct *work)
809{
810 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
811 sc_iput_work);
812 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
813
814 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
815}
816
817static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
818 struct nilfs_root *root)
819{
820 int ret = 0;
821
822 if (nilfs_mdt_fetch_dirty(root->ifile))
823 ret++;
824 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
825 ret++;
826 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
827 ret++;
828 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
829 ret++;
830 return ret;
831}
832
833static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
834{
835 return list_empty(&sci->sc_dirty_files) &&
836 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
837 sci->sc_nfreesegs == 0 &&
838 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
839}
840
841static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
842{
843 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
844 int ret = 0;
845
846 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
847 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
848
849 spin_lock(&nilfs->ns_inode_lock);
850 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
851 ret++;
852
853 spin_unlock(&nilfs->ns_inode_lock);
854 return ret;
855}
856
857static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
858{
859 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
860
861 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
862 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
863 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
864 nilfs_mdt_clear_dirty(nilfs->ns_dat);
865}
866
867static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
868{
869 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
870 struct buffer_head *bh_cp;
871 struct nilfs_checkpoint *raw_cp;
872 int err;
873
874 /* XXX: this interface will be changed */
875 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
876 &raw_cp, &bh_cp);
877 if (likely(!err)) {
878 /* The following code is duplicated with cpfile. But, it is
879 needed to collect the checkpoint even if it was not newly
880 created */
881 mark_buffer_dirty(bh_cp);
882 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
883 nilfs_cpfile_put_checkpoint(
884 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
885 } else
886 WARN_ON(err == -EINVAL || err == -ENOENT);
887
888 return err;
889}
890
891static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
892{
893 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
894 struct buffer_head *bh_cp;
895 struct nilfs_checkpoint *raw_cp;
896 int err;
897
898 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
899 &raw_cp, &bh_cp);
900 if (unlikely(err)) {
901 WARN_ON(err == -EINVAL || err == -ENOENT);
902 goto failed_ibh;
903 }
904 raw_cp->cp_snapshot_list.ssl_next = 0;
905 raw_cp->cp_snapshot_list.ssl_prev = 0;
906 raw_cp->cp_inodes_count =
907 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
908 raw_cp->cp_blocks_count =
909 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
910 raw_cp->cp_nblk_inc =
911 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
912 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
913 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
914
915 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
916 nilfs_checkpoint_clear_minor(raw_cp);
917 else
918 nilfs_checkpoint_set_minor(raw_cp);
919
920 nilfs_write_inode_common(sci->sc_root->ifile,
921 &raw_cp->cp_ifile_inode, 1);
922 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
923 return 0;
924
925 failed_ibh:
926 return err;
927}
928
929static void nilfs_fill_in_file_bmap(struct inode *ifile,
930 struct nilfs_inode_info *ii)
931
932{
933 struct buffer_head *ibh;
934 struct nilfs_inode *raw_inode;
935
936 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
937 ibh = ii->i_bh;
938 BUG_ON(!ibh);
939 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
940 ibh);
941 nilfs_bmap_write(ii->i_bmap, raw_inode);
942 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
943 }
944}
945
946static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
947{
948 struct nilfs_inode_info *ii;
949
950 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
951 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
952 set_bit(NILFS_I_COLLECTED, &ii->i_state);
953 }
954}
955
956static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
957 struct the_nilfs *nilfs)
958{
959 struct buffer_head *bh_sr;
960 struct nilfs_super_root *raw_sr;
961 unsigned isz, srsz;
962
963 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
964 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
965 isz = nilfs->ns_inode_size;
966 srsz = NILFS_SR_BYTES(isz);
967
968 raw_sr->sr_bytes = cpu_to_le16(srsz);
969 raw_sr->sr_nongc_ctime
970 = cpu_to_le64(nilfs_doing_gc() ?
971 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
972 raw_sr->sr_flags = 0;
973
974 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
975 NILFS_SR_DAT_OFFSET(isz), 1);
976 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
977 NILFS_SR_CPFILE_OFFSET(isz), 1);
978 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
979 NILFS_SR_SUFILE_OFFSET(isz), 1);
980 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
981}
982
983static void nilfs_redirty_inodes(struct list_head *head)
984{
985 struct nilfs_inode_info *ii;
986
987 list_for_each_entry(ii, head, i_dirty) {
988 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
989 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
990 }
991}
992
993static void nilfs_drop_collected_inodes(struct list_head *head)
994{
995 struct nilfs_inode_info *ii;
996
997 list_for_each_entry(ii, head, i_dirty) {
998 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
999 continue;
1000
1001 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
1002 set_bit(NILFS_I_UPDATED, &ii->i_state);
1003 }
1004}
1005
1006static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1007 struct inode *inode,
1008 struct list_head *listp,
1009 int (*collect)(struct nilfs_sc_info *,
1010 struct buffer_head *,
1011 struct inode *))
1012{
1013 struct buffer_head *bh, *n;
1014 int err = 0;
1015
1016 if (collect) {
1017 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1018 list_del_init(&bh->b_assoc_buffers);
1019 err = collect(sci, bh, inode);
1020 brelse(bh);
1021 if (unlikely(err))
1022 goto dispose_buffers;
1023 }
1024 return 0;
1025 }
1026
1027 dispose_buffers:
1028 while (!list_empty(listp)) {
1029 bh = list_first_entry(listp, struct buffer_head,
1030 b_assoc_buffers);
1031 list_del_init(&bh->b_assoc_buffers);
1032 brelse(bh);
1033 }
1034 return err;
1035}
1036
1037static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1038{
1039 /* Remaining number of blocks within segment buffer */
1040 return sci->sc_segbuf_nblocks -
1041 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1042}
1043
1044static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1045 struct inode *inode,
1046 struct nilfs_sc_operations *sc_ops)
1047{
1048 LIST_HEAD(data_buffers);
1049 LIST_HEAD(node_buffers);
1050 int err;
1051
1052 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1053 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1054
1055 n = nilfs_lookup_dirty_data_buffers(
1056 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1057 if (n > rest) {
1058 err = nilfs_segctor_apply_buffers(
1059 sci, inode, &data_buffers,
1060 sc_ops->collect_data);
1061 BUG_ON(!err); /* always receive -E2BIG or true error */
1062 goto break_or_fail;
1063 }
1064 }
1065 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1066
1067 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1068 err = nilfs_segctor_apply_buffers(
1069 sci, inode, &data_buffers, sc_ops->collect_data);
1070 if (unlikely(err)) {
1071 /* dispose node list */
1072 nilfs_segctor_apply_buffers(
1073 sci, inode, &node_buffers, NULL);
1074 goto break_or_fail;
1075 }
1076 sci->sc_stage.flags |= NILFS_CF_NODE;
1077 }
1078 /* Collect node */
1079 err = nilfs_segctor_apply_buffers(
1080 sci, inode, &node_buffers, sc_ops->collect_node);
1081 if (unlikely(err))
1082 goto break_or_fail;
1083
1084 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1085 err = nilfs_segctor_apply_buffers(
1086 sci, inode, &node_buffers, sc_ops->collect_bmap);
1087 if (unlikely(err))
1088 goto break_or_fail;
1089
1090 nilfs_segctor_end_finfo(sci, inode);
1091 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1092
1093 break_or_fail:
1094 return err;
1095}
1096
1097static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1098 struct inode *inode)
1099{
1100 LIST_HEAD(data_buffers);
1101 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1102 int err;
1103
1104 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1105 sci->sc_dsync_start,
1106 sci->sc_dsync_end);
1107
1108 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1109 nilfs_collect_file_data);
1110 if (!err) {
1111 nilfs_segctor_end_finfo(sci, inode);
1112 BUG_ON(n > rest);
1113 /* always receive -E2BIG or true error if n > rest */
1114 }
1115 return err;
1116}
1117
1118static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1119{
1120 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1121 struct list_head *head;
1122 struct nilfs_inode_info *ii;
1123 size_t ndone;
1124 int err = 0;
1125
1126 switch (nilfs_sc_cstage_get(sci)) {
1127 case NILFS_ST_INIT:
1128 /* Pre-processes */
1129 sci->sc_stage.flags = 0;
1130
1131 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1132 sci->sc_nblk_inc = 0;
1133 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1134 if (mode == SC_LSEG_DSYNC) {
1135 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1136 goto dsync_mode;
1137 }
1138 }
1139
1140 sci->sc_stage.dirty_file_ptr = NULL;
1141 sci->sc_stage.gc_inode_ptr = NULL;
1142 if (mode == SC_FLUSH_DAT) {
1143 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1144 goto dat_stage;
1145 }
1146 nilfs_sc_cstage_inc(sci); /* Fall through */
1147 case NILFS_ST_GC:
1148 if (nilfs_doing_gc()) {
1149 head = &sci->sc_gc_inodes;
1150 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1151 head, i_dirty);
1152 list_for_each_entry_continue(ii, head, i_dirty) {
1153 err = nilfs_segctor_scan_file(
1154 sci, &ii->vfs_inode,
1155 &nilfs_sc_file_ops);
1156 if (unlikely(err)) {
1157 sci->sc_stage.gc_inode_ptr = list_entry(
1158 ii->i_dirty.prev,
1159 struct nilfs_inode_info,
1160 i_dirty);
1161 goto break_or_fail;
1162 }
1163 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1164 }
1165 sci->sc_stage.gc_inode_ptr = NULL;
1166 }
1167 nilfs_sc_cstage_inc(sci); /* Fall through */
1168 case NILFS_ST_FILE:
1169 head = &sci->sc_dirty_files;
1170 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1171 i_dirty);
1172 list_for_each_entry_continue(ii, head, i_dirty) {
1173 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1174
1175 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1176 &nilfs_sc_file_ops);
1177 if (unlikely(err)) {
1178 sci->sc_stage.dirty_file_ptr =
1179 list_entry(ii->i_dirty.prev,
1180 struct nilfs_inode_info,
1181 i_dirty);
1182 goto break_or_fail;
1183 }
1184 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1185 /* XXX: required ? */
1186 }
1187 sci->sc_stage.dirty_file_ptr = NULL;
1188 if (mode == SC_FLUSH_FILE) {
1189 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1190 return 0;
1191 }
1192 nilfs_sc_cstage_inc(sci);
1193 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1194 /* Fall through */
1195 case NILFS_ST_IFILE:
1196 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1197 &nilfs_sc_file_ops);
1198 if (unlikely(err))
1199 break;
1200 nilfs_sc_cstage_inc(sci);
1201 /* Creating a checkpoint */
1202 err = nilfs_segctor_create_checkpoint(sci);
1203 if (unlikely(err))
1204 break;
1205 /* Fall through */
1206 case NILFS_ST_CPFILE:
1207 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1208 &nilfs_sc_file_ops);
1209 if (unlikely(err))
1210 break;
1211 nilfs_sc_cstage_inc(sci); /* Fall through */
1212 case NILFS_ST_SUFILE:
1213 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1214 sci->sc_nfreesegs, &ndone);
1215 if (unlikely(err)) {
1216 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1217 sci->sc_freesegs, ndone,
1218 NULL);
1219 break;
1220 }
1221 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1222
1223 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1224 &nilfs_sc_file_ops);
1225 if (unlikely(err))
1226 break;
1227 nilfs_sc_cstage_inc(sci); /* Fall through */
1228 case NILFS_ST_DAT:
1229 dat_stage:
1230 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1231 &nilfs_sc_dat_ops);
1232 if (unlikely(err))
1233 break;
1234 if (mode == SC_FLUSH_DAT) {
1235 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1236 return 0;
1237 }
1238 nilfs_sc_cstage_inc(sci); /* Fall through */
1239 case NILFS_ST_SR:
1240 if (mode == SC_LSEG_SR) {
1241 /* Appending a super root */
1242 err = nilfs_segctor_add_super_root(sci);
1243 if (unlikely(err))
1244 break;
1245 }
1246 /* End of a logical segment */
1247 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1248 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1249 return 0;
1250 case NILFS_ST_DSYNC:
1251 dsync_mode:
1252 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1253 ii = sci->sc_dsync_inode;
1254 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1255 break;
1256
1257 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1258 if (unlikely(err))
1259 break;
1260 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1261 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1262 return 0;
1263 case NILFS_ST_DONE:
1264 return 0;
1265 default:
1266 BUG();
1267 }
1268
1269 break_or_fail:
1270 return err;
1271}
1272
1273/**
1274 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1275 * @sci: nilfs_sc_info
1276 * @nilfs: nilfs object
1277 */
1278static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1279 struct the_nilfs *nilfs)
1280{
1281 struct nilfs_segment_buffer *segbuf, *prev;
1282 __u64 nextnum;
1283 int err, alloc = 0;
1284
1285 segbuf = nilfs_segbuf_new(sci->sc_super);
1286 if (unlikely(!segbuf))
1287 return -ENOMEM;
1288
1289 if (list_empty(&sci->sc_write_logs)) {
1290 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1291 nilfs->ns_pseg_offset, nilfs);
1292 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1293 nilfs_shift_to_next_segment(nilfs);
1294 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1295 }
1296
1297 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1298 nextnum = nilfs->ns_nextnum;
1299
1300 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1301 /* Start from the head of a new full segment */
1302 alloc++;
1303 } else {
1304 /* Continue logs */
1305 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1306 nilfs_segbuf_map_cont(segbuf, prev);
1307 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1308 nextnum = prev->sb_nextnum;
1309
1310 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1311 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1312 segbuf->sb_sum.seg_seq++;
1313 alloc++;
1314 }
1315 }
1316
1317 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1318 if (err)
1319 goto failed;
1320
1321 if (alloc) {
1322 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1323 if (err)
1324 goto failed;
1325 }
1326 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1327
1328 BUG_ON(!list_empty(&sci->sc_segbufs));
1329 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1330 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1331 return 0;
1332
1333 failed:
1334 nilfs_segbuf_free(segbuf);
1335 return err;
1336}
1337
1338static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1339 struct the_nilfs *nilfs, int nadd)
1340{
1341 struct nilfs_segment_buffer *segbuf, *prev;
1342 struct inode *sufile = nilfs->ns_sufile;
1343 __u64 nextnextnum;
1344 LIST_HEAD(list);
1345 int err, ret, i;
1346
1347 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1348 /*
1349 * Since the segment specified with nextnum might be allocated during
1350 * the previous construction, the buffer including its segusage may
1351 * not be dirty. The following call ensures that the buffer is dirty
1352 * and will pin the buffer on memory until the sufile is written.
1353 */
1354 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1355 if (unlikely(err))
1356 return err;
1357
1358 for (i = 0; i < nadd; i++) {
1359 /* extend segment info */
1360 err = -ENOMEM;
1361 segbuf = nilfs_segbuf_new(sci->sc_super);
1362 if (unlikely(!segbuf))
1363 goto failed;
1364
1365 /* map this buffer to region of segment on-disk */
1366 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1367 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1368
1369 /* allocate the next next full segment */
1370 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1371 if (unlikely(err))
1372 goto failed_segbuf;
1373
1374 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1375 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1376
1377 list_add_tail(&segbuf->sb_list, &list);
1378 prev = segbuf;
1379 }
1380 list_splice_tail(&list, &sci->sc_segbufs);
1381 return 0;
1382
1383 failed_segbuf:
1384 nilfs_segbuf_free(segbuf);
1385 failed:
1386 list_for_each_entry(segbuf, &list, sb_list) {
1387 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1388 WARN_ON(ret); /* never fails */
1389 }
1390 nilfs_destroy_logs(&list);
1391 return err;
1392}
1393
1394static void nilfs_free_incomplete_logs(struct list_head *logs,
1395 struct the_nilfs *nilfs)
1396{
1397 struct nilfs_segment_buffer *segbuf, *prev;
1398 struct inode *sufile = nilfs->ns_sufile;
1399 int ret;
1400
1401 segbuf = NILFS_FIRST_SEGBUF(logs);
1402 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1403 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1404 WARN_ON(ret); /* never fails */
1405 }
1406 if (atomic_read(&segbuf->sb_err)) {
1407 /* Case 1: The first segment failed */
1408 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1409 /* Case 1a: Partial segment appended into an existing
1410 segment */
1411 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1412 segbuf->sb_fseg_end);
1413 else /* Case 1b: New full segment */
1414 set_nilfs_discontinued(nilfs);
1415 }
1416
1417 prev = segbuf;
1418 list_for_each_entry_continue(segbuf, logs, sb_list) {
1419 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1420 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1421 WARN_ON(ret); /* never fails */
1422 }
1423 if (atomic_read(&segbuf->sb_err) &&
1424 segbuf->sb_segnum != nilfs->ns_nextnum)
1425 /* Case 2: extended segment (!= next) failed */
1426 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1427 prev = segbuf;
1428 }
1429}
1430
1431static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1432 struct inode *sufile)
1433{
1434 struct nilfs_segment_buffer *segbuf;
1435 unsigned long live_blocks;
1436 int ret;
1437
1438 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1439 live_blocks = segbuf->sb_sum.nblocks +
1440 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1441 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1442 live_blocks,
1443 sci->sc_seg_ctime);
1444 WARN_ON(ret); /* always succeed because the segusage is dirty */
1445 }
1446}
1447
1448static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1449{
1450 struct nilfs_segment_buffer *segbuf;
1451 int ret;
1452
1453 segbuf = NILFS_FIRST_SEGBUF(logs);
1454 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1455 segbuf->sb_pseg_start -
1456 segbuf->sb_fseg_start, 0);
1457 WARN_ON(ret); /* always succeed because the segusage is dirty */
1458
1459 list_for_each_entry_continue(segbuf, logs, sb_list) {
1460 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1461 0, 0);
1462 WARN_ON(ret); /* always succeed */
1463 }
1464}
1465
1466static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1467 struct nilfs_segment_buffer *last,
1468 struct inode *sufile)
1469{
1470 struct nilfs_segment_buffer *segbuf = last;
1471 int ret;
1472
1473 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1474 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1475 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1476 WARN_ON(ret);
1477 }
1478 nilfs_truncate_logs(&sci->sc_segbufs, last);
1479}
1480
1481
1482static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1483 struct the_nilfs *nilfs, int mode)
1484{
1485 struct nilfs_cstage prev_stage = sci->sc_stage;
1486 int err, nadd = 1;
1487
1488 /* Collection retry loop */
1489 for (;;) {
1490 sci->sc_nblk_this_inc = 0;
1491 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1492
1493 err = nilfs_segctor_reset_segment_buffer(sci);
1494 if (unlikely(err))
1495 goto failed;
1496
1497 err = nilfs_segctor_collect_blocks(sci, mode);
1498 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1499 if (!err)
1500 break;
1501
1502 if (unlikely(err != -E2BIG))
1503 goto failed;
1504
1505 /* The current segment is filled up */
1506 if (mode != SC_LSEG_SR ||
1507 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1508 break;
1509
1510 nilfs_clear_logs(&sci->sc_segbufs);
1511
1512 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1513 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1514 sci->sc_freesegs,
1515 sci->sc_nfreesegs,
1516 NULL);
1517 WARN_ON(err); /* do not happen */
1518 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1519 }
1520
1521 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1522 if (unlikely(err))
1523 return err;
1524
1525 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1526 sci->sc_stage = prev_stage;
1527 }
1528 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1529 return 0;
1530
1531 failed:
1532 return err;
1533}
1534
1535static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1536 struct buffer_head *new_bh)
1537{
1538 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1539
1540 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1541 /* The caller must release old_bh */
1542}
1543
1544static int
1545nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1546 struct nilfs_segment_buffer *segbuf,
1547 int mode)
1548{
1549 struct inode *inode = NULL;
1550 sector_t blocknr;
1551 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1552 unsigned long nblocks = 0, ndatablk = 0;
1553 struct nilfs_sc_operations *sc_op = NULL;
1554 struct nilfs_segsum_pointer ssp;
1555 struct nilfs_finfo *finfo = NULL;
1556 union nilfs_binfo binfo;
1557 struct buffer_head *bh, *bh_org;
1558 ino_t ino = 0;
1559 int err = 0;
1560
1561 if (!nfinfo)
1562 goto out;
1563
1564 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1565 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1566 ssp.offset = sizeof(struct nilfs_segment_summary);
1567
1568 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1569 if (bh == segbuf->sb_super_root)
1570 break;
1571 if (!finfo) {
1572 finfo = nilfs_segctor_map_segsum_entry(
1573 sci, &ssp, sizeof(*finfo));
1574 ino = le64_to_cpu(finfo->fi_ino);
1575 nblocks = le32_to_cpu(finfo->fi_nblocks);
1576 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1577
1578 inode = bh->b_page->mapping->host;
1579
1580 if (mode == SC_LSEG_DSYNC)
1581 sc_op = &nilfs_sc_dsync_ops;
1582 else if (ino == NILFS_DAT_INO)
1583 sc_op = &nilfs_sc_dat_ops;
1584 else /* file blocks */
1585 sc_op = &nilfs_sc_file_ops;
1586 }
1587 bh_org = bh;
1588 get_bh(bh_org);
1589 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1590 &binfo);
1591 if (bh != bh_org)
1592 nilfs_list_replace_buffer(bh_org, bh);
1593 brelse(bh_org);
1594 if (unlikely(err))
1595 goto failed_bmap;
1596
1597 if (ndatablk > 0)
1598 sc_op->write_data_binfo(sci, &ssp, &binfo);
1599 else
1600 sc_op->write_node_binfo(sci, &ssp, &binfo);
1601
1602 blocknr++;
1603 if (--nblocks == 0) {
1604 finfo = NULL;
1605 if (--nfinfo == 0)
1606 break;
1607 } else if (ndatablk > 0)
1608 ndatablk--;
1609 }
1610 out:
1611 return 0;
1612
1613 failed_bmap:
1614 return err;
1615}
1616
1617static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1618{
1619 struct nilfs_segment_buffer *segbuf;
1620 int err;
1621
1622 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1623 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1624 if (unlikely(err))
1625 return err;
1626 nilfs_segbuf_fill_in_segsum(segbuf);
1627 }
1628 return 0;
1629}
1630
1631static void nilfs_begin_page_io(struct page *page)
1632{
1633 if (!page || PageWriteback(page))
1634 /* For split b-tree node pages, this function may be called
1635 twice. We ignore the 2nd or later calls by this check. */
1636 return;
1637
1638 lock_page(page);
1639 clear_page_dirty_for_io(page);
1640 set_page_writeback(page);
1641 unlock_page(page);
1642}
1643
1644static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1645{
1646 struct nilfs_segment_buffer *segbuf;
1647 struct page *bd_page = NULL, *fs_page = NULL;
1648
1649 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1650 struct buffer_head *bh;
1651
1652 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1653 b_assoc_buffers) {
1654 if (bh->b_page != bd_page) {
1655 if (bd_page) {
1656 lock_page(bd_page);
1657 clear_page_dirty_for_io(bd_page);
1658 set_page_writeback(bd_page);
1659 unlock_page(bd_page);
1660 }
1661 bd_page = bh->b_page;
1662 }
1663 }
1664
1665 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1666 b_assoc_buffers) {
1667 set_buffer_async_write(bh);
1668 if (bh == segbuf->sb_super_root) {
1669 if (bh->b_page != bd_page) {
1670 lock_page(bd_page);
1671 clear_page_dirty_for_io(bd_page);
1672 set_page_writeback(bd_page);
1673 unlock_page(bd_page);
1674 bd_page = bh->b_page;
1675 }
1676 break;
1677 }
1678 if (bh->b_page != fs_page) {
1679 nilfs_begin_page_io(fs_page);
1680 fs_page = bh->b_page;
1681 }
1682 }
1683 }
1684 if (bd_page) {
1685 lock_page(bd_page);
1686 clear_page_dirty_for_io(bd_page);
1687 set_page_writeback(bd_page);
1688 unlock_page(bd_page);
1689 }
1690 nilfs_begin_page_io(fs_page);
1691}
1692
1693static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1694 struct the_nilfs *nilfs)
1695{
1696 int ret;
1697
1698 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1699 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1700 return ret;
1701}
1702
1703static void nilfs_end_page_io(struct page *page, int err)
1704{
1705 if (!page)
1706 return;
1707
1708 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1709 /*
1710 * For b-tree node pages, this function may be called twice
1711 * or more because they might be split in a segment.
1712 */
1713 if (PageDirty(page)) {
1714 /*
1715 * For pages holding split b-tree node buffers, dirty
1716 * flag on the buffers may be cleared discretely.
1717 * In that case, the page is once redirtied for
1718 * remaining buffers, and it must be cancelled if
1719 * all the buffers get cleaned later.
1720 */
1721 lock_page(page);
1722 if (nilfs_page_buffers_clean(page))
1723 __nilfs_clear_page_dirty(page);
1724 unlock_page(page);
1725 }
1726 return;
1727 }
1728
1729 if (!err) {
1730 if (!nilfs_page_buffers_clean(page))
1731 __set_page_dirty_nobuffers(page);
1732 ClearPageError(page);
1733 } else {
1734 __set_page_dirty_nobuffers(page);
1735 SetPageError(page);
1736 }
1737
1738 end_page_writeback(page);
1739}
1740
1741static void nilfs_abort_logs(struct list_head *logs, int err)
1742{
1743 struct nilfs_segment_buffer *segbuf;
1744 struct page *bd_page = NULL, *fs_page = NULL;
1745 struct buffer_head *bh;
1746
1747 if (list_empty(logs))
1748 return;
1749
1750 list_for_each_entry(segbuf, logs, sb_list) {
1751 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1752 b_assoc_buffers) {
1753 if (bh->b_page != bd_page) {
1754 if (bd_page)
1755 end_page_writeback(bd_page);
1756 bd_page = bh->b_page;
1757 }
1758 }
1759
1760 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1761 b_assoc_buffers) {
1762 clear_buffer_async_write(bh);
1763 if (bh == segbuf->sb_super_root) {
1764 if (bh->b_page != bd_page) {
1765 end_page_writeback(bd_page);
1766 bd_page = bh->b_page;
1767 }
1768 break;
1769 }
1770 if (bh->b_page != fs_page) {
1771 nilfs_end_page_io(fs_page, err);
1772 fs_page = bh->b_page;
1773 }
1774 }
1775 }
1776 if (bd_page)
1777 end_page_writeback(bd_page);
1778
1779 nilfs_end_page_io(fs_page, err);
1780}
1781
1782static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1783 struct the_nilfs *nilfs, int err)
1784{
1785 LIST_HEAD(logs);
1786 int ret;
1787
1788 list_splice_tail_init(&sci->sc_write_logs, &logs);
1789 ret = nilfs_wait_on_logs(&logs);
1790 nilfs_abort_logs(&logs, ret ? : err);
1791
1792 list_splice_tail_init(&sci->sc_segbufs, &logs);
1793 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1794 nilfs_free_incomplete_logs(&logs, nilfs);
1795
1796 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1797 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1798 sci->sc_freesegs,
1799 sci->sc_nfreesegs,
1800 NULL);
1801 WARN_ON(ret); /* do not happen */
1802 }
1803
1804 nilfs_destroy_logs(&logs);
1805}
1806
1807static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1808 struct nilfs_segment_buffer *segbuf)
1809{
1810 nilfs->ns_segnum = segbuf->sb_segnum;
1811 nilfs->ns_nextnum = segbuf->sb_nextnum;
1812 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1813 + segbuf->sb_sum.nblocks;
1814 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1815 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1816}
1817
1818static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1819{
1820 struct nilfs_segment_buffer *segbuf;
1821 struct page *bd_page = NULL, *fs_page = NULL;
1822 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1823 int update_sr = false;
1824
1825 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1826 struct buffer_head *bh;
1827
1828 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1829 b_assoc_buffers) {
1830 set_buffer_uptodate(bh);
1831 clear_buffer_dirty(bh);
1832 if (bh->b_page != bd_page) {
1833 if (bd_page)
1834 end_page_writeback(bd_page);
1835 bd_page = bh->b_page;
1836 }
1837 }
1838 /*
1839 * We assume that the buffers which belong to the same page
1840 * continue over the buffer list.
1841 * Under this assumption, the last BHs of pages is
1842 * identifiable by the discontinuity of bh->b_page
1843 * (page != fs_page).
1844 *
1845 * For B-tree node blocks, however, this assumption is not
1846 * guaranteed. The cleanup code of B-tree node pages needs
1847 * special care.
1848 */
1849 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1850 b_assoc_buffers) {
1851 const unsigned long set_bits = (1 << BH_Uptodate);
1852 const unsigned long clear_bits =
1853 (1 << BH_Dirty | 1 << BH_Async_Write |
1854 1 << BH_Delay | 1 << BH_NILFS_Volatile |
1855 1 << BH_NILFS_Redirected);
1856
1857 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1858 if (bh == segbuf->sb_super_root) {
1859 if (bh->b_page != bd_page) {
1860 end_page_writeback(bd_page);
1861 bd_page = bh->b_page;
1862 }
1863 update_sr = true;
1864 break;
1865 }
1866 if (bh->b_page != fs_page) {
1867 nilfs_end_page_io(fs_page, 0);
1868 fs_page = bh->b_page;
1869 }
1870 }
1871
1872 if (!nilfs_segbuf_simplex(segbuf)) {
1873 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1874 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1875 sci->sc_lseg_stime = jiffies;
1876 }
1877 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1878 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1879 }
1880 }
1881 /*
1882 * Since pages may continue over multiple segment buffers,
1883 * end of the last page must be checked outside of the loop.
1884 */
1885 if (bd_page)
1886 end_page_writeback(bd_page);
1887
1888 nilfs_end_page_io(fs_page, 0);
1889
1890 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1891
1892 if (nilfs_doing_gc())
1893 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1894 else
1895 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1896
1897 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1898
1899 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1900 nilfs_set_next_segment(nilfs, segbuf);
1901
1902 if (update_sr) {
1903 nilfs->ns_flushed_device = 0;
1904 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1905 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1906
1907 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1908 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1909 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1910 nilfs_segctor_clear_metadata_dirty(sci);
1911 } else
1912 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1913}
1914
1915static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1916{
1917 int ret;
1918
1919 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1920 if (!ret) {
1921 nilfs_segctor_complete_write(sci);
1922 nilfs_destroy_logs(&sci->sc_write_logs);
1923 }
1924 return ret;
1925}
1926
1927static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1928 struct the_nilfs *nilfs)
1929{
1930 struct nilfs_inode_info *ii, *n;
1931 struct inode *ifile = sci->sc_root->ifile;
1932
1933 spin_lock(&nilfs->ns_inode_lock);
1934 retry:
1935 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1936 if (!ii->i_bh) {
1937 struct buffer_head *ibh;
1938 int err;
1939
1940 spin_unlock(&nilfs->ns_inode_lock);
1941 err = nilfs_ifile_get_inode_block(
1942 ifile, ii->vfs_inode.i_ino, &ibh);
1943 if (unlikely(err)) {
1944 nilfs_warning(sci->sc_super, __func__,
1945 "failed to get inode block.\n");
1946 return err;
1947 }
1948 mark_buffer_dirty(ibh);
1949 nilfs_mdt_mark_dirty(ifile);
1950 spin_lock(&nilfs->ns_inode_lock);
1951 if (likely(!ii->i_bh))
1952 ii->i_bh = ibh;
1953 else
1954 brelse(ibh);
1955 goto retry;
1956 }
1957
1958 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1959 set_bit(NILFS_I_BUSY, &ii->i_state);
1960 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1961 }
1962 spin_unlock(&nilfs->ns_inode_lock);
1963
1964 return 0;
1965}
1966
1967static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1968 struct the_nilfs *nilfs)
1969{
1970 struct nilfs_inode_info *ii, *n;
1971 int during_mount = !(sci->sc_super->s_flags & MS_ACTIVE);
1972 int defer_iput = false;
1973
1974 spin_lock(&nilfs->ns_inode_lock);
1975 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1976 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1977 test_bit(NILFS_I_DIRTY, &ii->i_state))
1978 continue;
1979
1980 clear_bit(NILFS_I_BUSY, &ii->i_state);
1981 brelse(ii->i_bh);
1982 ii->i_bh = NULL;
1983 list_del_init(&ii->i_dirty);
1984 if (!ii->vfs_inode.i_nlink || during_mount) {
1985 /*
1986 * Defer calling iput() to avoid deadlocks if
1987 * i_nlink == 0 or mount is not yet finished.
1988 */
1989 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
1990 defer_iput = true;
1991 } else {
1992 spin_unlock(&nilfs->ns_inode_lock);
1993 iput(&ii->vfs_inode);
1994 spin_lock(&nilfs->ns_inode_lock);
1995 }
1996 }
1997 spin_unlock(&nilfs->ns_inode_lock);
1998
1999 if (defer_iput)
2000 schedule_work(&sci->sc_iput_work);
2001}
2002
2003/*
2004 * Main procedure of segment constructor
2005 */
2006static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2007{
2008 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2009 int err;
2010
2011 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2012 sci->sc_cno = nilfs->ns_cno;
2013
2014 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2015 if (unlikely(err))
2016 goto out;
2017
2018 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2019 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2020
2021 if (nilfs_segctor_clean(sci))
2022 goto out;
2023
2024 do {
2025 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2026
2027 err = nilfs_segctor_begin_construction(sci, nilfs);
2028 if (unlikely(err))
2029 goto out;
2030
2031 /* Update time stamp */
2032 sci->sc_seg_ctime = get_seconds();
2033
2034 err = nilfs_segctor_collect(sci, nilfs, mode);
2035 if (unlikely(err))
2036 goto failed;
2037
2038 /* Avoid empty segment */
2039 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2040 nilfs_segbuf_empty(sci->sc_curseg)) {
2041 nilfs_segctor_abort_construction(sci, nilfs, 1);
2042 goto out;
2043 }
2044
2045 err = nilfs_segctor_assign(sci, mode);
2046 if (unlikely(err))
2047 goto failed;
2048
2049 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2050 nilfs_segctor_fill_in_file_bmap(sci);
2051
2052 if (mode == SC_LSEG_SR &&
2053 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2054 err = nilfs_segctor_fill_in_checkpoint(sci);
2055 if (unlikely(err))
2056 goto failed_to_write;
2057
2058 nilfs_segctor_fill_in_super_root(sci, nilfs);
2059 }
2060 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2061
2062 /* Write partial segments */
2063 nilfs_segctor_prepare_write(sci);
2064
2065 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2066 nilfs->ns_crc_seed);
2067
2068 err = nilfs_segctor_write(sci, nilfs);
2069 if (unlikely(err))
2070 goto failed_to_write;
2071
2072 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2073 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2074 /*
2075 * At this point, we avoid double buffering
2076 * for blocksize < pagesize because page dirty
2077 * flag is turned off during write and dirty
2078 * buffers are not properly collected for
2079 * pages crossing over segments.
2080 */
2081 err = nilfs_segctor_wait(sci);
2082 if (err)
2083 goto failed_to_write;
2084 }
2085 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2086
2087 out:
2088 nilfs_segctor_drop_written_files(sci, nilfs);
2089 return err;
2090
2091 failed_to_write:
2092 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2093 nilfs_redirty_inodes(&sci->sc_dirty_files);
2094
2095 failed:
2096 if (nilfs_doing_gc())
2097 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2098 nilfs_segctor_abort_construction(sci, nilfs, err);
2099 goto out;
2100}
2101
2102/**
2103 * nilfs_segctor_start_timer - set timer of background write
2104 * @sci: nilfs_sc_info
2105 *
2106 * If the timer has already been set, it ignores the new request.
2107 * This function MUST be called within a section locking the segment
2108 * semaphore.
2109 */
2110static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2111{
2112 spin_lock(&sci->sc_state_lock);
2113 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2114 sci->sc_timer.expires = jiffies + sci->sc_interval;
2115 add_timer(&sci->sc_timer);
2116 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2117 }
2118 spin_unlock(&sci->sc_state_lock);
2119}
2120
2121static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2122{
2123 spin_lock(&sci->sc_state_lock);
2124 if (!(sci->sc_flush_request & (1 << bn))) {
2125 unsigned long prev_req = sci->sc_flush_request;
2126
2127 sci->sc_flush_request |= (1 << bn);
2128 if (!prev_req)
2129 wake_up(&sci->sc_wait_daemon);
2130 }
2131 spin_unlock(&sci->sc_state_lock);
2132}
2133
2134/**
2135 * nilfs_flush_segment - trigger a segment construction for resource control
2136 * @sb: super block
2137 * @ino: inode number of the file to be flushed out.
2138 */
2139void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2140{
2141 struct the_nilfs *nilfs = sb->s_fs_info;
2142 struct nilfs_sc_info *sci = nilfs->ns_writer;
2143
2144 if (!sci || nilfs_doing_construction())
2145 return;
2146 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2147 /* assign bit 0 to data files */
2148}
2149
2150struct nilfs_segctor_wait_request {
2151 wait_queue_t wq;
2152 __u32 seq;
2153 int err;
2154 atomic_t done;
2155};
2156
2157static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2158{
2159 struct nilfs_segctor_wait_request wait_req;
2160 int err = 0;
2161
2162 spin_lock(&sci->sc_state_lock);
2163 init_wait(&wait_req.wq);
2164 wait_req.err = 0;
2165 atomic_set(&wait_req.done, 0);
2166 wait_req.seq = ++sci->sc_seq_request;
2167 spin_unlock(&sci->sc_state_lock);
2168
2169 init_waitqueue_entry(&wait_req.wq, current);
2170 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2171 set_current_state(TASK_INTERRUPTIBLE);
2172 wake_up(&sci->sc_wait_daemon);
2173
2174 for (;;) {
2175 if (atomic_read(&wait_req.done)) {
2176 err = wait_req.err;
2177 break;
2178 }
2179 if (!signal_pending(current)) {
2180 schedule();
2181 continue;
2182 }
2183 err = -ERESTARTSYS;
2184 break;
2185 }
2186 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2187 return err;
2188}
2189
2190static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2191{
2192 struct nilfs_segctor_wait_request *wrq, *n;
2193 unsigned long flags;
2194
2195 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2196 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2197 wq.task_list) {
2198 if (!atomic_read(&wrq->done) &&
2199 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2200 wrq->err = err;
2201 atomic_set(&wrq->done, 1);
2202 }
2203 if (atomic_read(&wrq->done)) {
2204 wrq->wq.func(&wrq->wq,
2205 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2206 0, NULL);
2207 }
2208 }
2209 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2210}
2211
2212/**
2213 * nilfs_construct_segment - construct a logical segment
2214 * @sb: super block
2215 *
2216 * Return Value: On success, 0 is retured. On errors, one of the following
2217 * negative error code is returned.
2218 *
2219 * %-EROFS - Read only filesystem.
2220 *
2221 * %-EIO - I/O error
2222 *
2223 * %-ENOSPC - No space left on device (only in a panic state).
2224 *
2225 * %-ERESTARTSYS - Interrupted.
2226 *
2227 * %-ENOMEM - Insufficient memory available.
2228 */
2229int nilfs_construct_segment(struct super_block *sb)
2230{
2231 struct the_nilfs *nilfs = sb->s_fs_info;
2232 struct nilfs_sc_info *sci = nilfs->ns_writer;
2233 struct nilfs_transaction_info *ti;
2234 int err;
2235
2236 if (!sci)
2237 return -EROFS;
2238
2239 /* A call inside transactions causes a deadlock. */
2240 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2241
2242 err = nilfs_segctor_sync(sci);
2243 return err;
2244}
2245
2246/**
2247 * nilfs_construct_dsync_segment - construct a data-only logical segment
2248 * @sb: super block
2249 * @inode: inode whose data blocks should be written out
2250 * @start: start byte offset
2251 * @end: end byte offset (inclusive)
2252 *
2253 * Return Value: On success, 0 is retured. On errors, one of the following
2254 * negative error code is returned.
2255 *
2256 * %-EROFS - Read only filesystem.
2257 *
2258 * %-EIO - I/O error
2259 *
2260 * %-ENOSPC - No space left on device (only in a panic state).
2261 *
2262 * %-ERESTARTSYS - Interrupted.
2263 *
2264 * %-ENOMEM - Insufficient memory available.
2265 */
2266int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2267 loff_t start, loff_t end)
2268{
2269 struct the_nilfs *nilfs = sb->s_fs_info;
2270 struct nilfs_sc_info *sci = nilfs->ns_writer;
2271 struct nilfs_inode_info *ii;
2272 struct nilfs_transaction_info ti;
2273 int err = 0;
2274
2275 if (!sci)
2276 return -EROFS;
2277
2278 nilfs_transaction_lock(sb, &ti, 0);
2279
2280 ii = NILFS_I(inode);
2281 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2282 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2283 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2284 nilfs_discontinued(nilfs)) {
2285 nilfs_transaction_unlock(sb);
2286 err = nilfs_segctor_sync(sci);
2287 return err;
2288 }
2289
2290 spin_lock(&nilfs->ns_inode_lock);
2291 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2292 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2293 spin_unlock(&nilfs->ns_inode_lock);
2294 nilfs_transaction_unlock(sb);
2295 return 0;
2296 }
2297 spin_unlock(&nilfs->ns_inode_lock);
2298 sci->sc_dsync_inode = ii;
2299 sci->sc_dsync_start = start;
2300 sci->sc_dsync_end = end;
2301
2302 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2303 if (!err)
2304 nilfs->ns_flushed_device = 0;
2305
2306 nilfs_transaction_unlock(sb);
2307 return err;
2308}
2309
2310#define FLUSH_FILE_BIT (0x1) /* data file only */
2311#define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2312
2313/**
2314 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2315 * @sci: segment constructor object
2316 */
2317static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2318{
2319 spin_lock(&sci->sc_state_lock);
2320 sci->sc_seq_accepted = sci->sc_seq_request;
2321 spin_unlock(&sci->sc_state_lock);
2322 del_timer_sync(&sci->sc_timer);
2323}
2324
2325/**
2326 * nilfs_segctor_notify - notify the result of request to caller threads
2327 * @sci: segment constructor object
2328 * @mode: mode of log forming
2329 * @err: error code to be notified
2330 */
2331static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2332{
2333 /* Clear requests (even when the construction failed) */
2334 spin_lock(&sci->sc_state_lock);
2335
2336 if (mode == SC_LSEG_SR) {
2337 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2338 sci->sc_seq_done = sci->sc_seq_accepted;
2339 nilfs_segctor_wakeup(sci, err);
2340 sci->sc_flush_request = 0;
2341 } else {
2342 if (mode == SC_FLUSH_FILE)
2343 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2344 else if (mode == SC_FLUSH_DAT)
2345 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2346
2347 /* re-enable timer if checkpoint creation was not done */
2348 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2349 time_before(jiffies, sci->sc_timer.expires))
2350 add_timer(&sci->sc_timer);
2351 }
2352 spin_unlock(&sci->sc_state_lock);
2353}
2354
2355/**
2356 * nilfs_segctor_construct - form logs and write them to disk
2357 * @sci: segment constructor object
2358 * @mode: mode of log forming
2359 */
2360static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2361{
2362 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2363 struct nilfs_super_block **sbp;
2364 int err = 0;
2365
2366 nilfs_segctor_accept(sci);
2367
2368 if (nilfs_discontinued(nilfs))
2369 mode = SC_LSEG_SR;
2370 if (!nilfs_segctor_confirm(sci))
2371 err = nilfs_segctor_do_construct(sci, mode);
2372
2373 if (likely(!err)) {
2374 if (mode != SC_FLUSH_DAT)
2375 atomic_set(&nilfs->ns_ndirtyblks, 0);
2376 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2377 nilfs_discontinued(nilfs)) {
2378 down_write(&nilfs->ns_sem);
2379 err = -EIO;
2380 sbp = nilfs_prepare_super(sci->sc_super,
2381 nilfs_sb_will_flip(nilfs));
2382 if (likely(sbp)) {
2383 nilfs_set_log_cursor(sbp[0], nilfs);
2384 err = nilfs_commit_super(sci->sc_super,
2385 NILFS_SB_COMMIT);
2386 }
2387 up_write(&nilfs->ns_sem);
2388 }
2389 }
2390
2391 nilfs_segctor_notify(sci, mode, err);
2392 return err;
2393}
2394
2395static void nilfs_construction_timeout(unsigned long data)
2396{
2397 struct task_struct *p = (struct task_struct *)data;
2398 wake_up_process(p);
2399}
2400
2401static void
2402nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2403{
2404 struct nilfs_inode_info *ii, *n;
2405
2406 list_for_each_entry_safe(ii, n, head, i_dirty) {
2407 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2408 continue;
2409 list_del_init(&ii->i_dirty);
2410 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2411 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2412 iput(&ii->vfs_inode);
2413 }
2414}
2415
2416int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2417 void **kbufs)
2418{
2419 struct the_nilfs *nilfs = sb->s_fs_info;
2420 struct nilfs_sc_info *sci = nilfs->ns_writer;
2421 struct nilfs_transaction_info ti;
2422 int err;
2423
2424 if (unlikely(!sci))
2425 return -EROFS;
2426
2427 nilfs_transaction_lock(sb, &ti, 1);
2428
2429 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2430 if (unlikely(err))
2431 goto out_unlock;
2432
2433 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2434 if (unlikely(err)) {
2435 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2436 goto out_unlock;
2437 }
2438
2439 sci->sc_freesegs = kbufs[4];
2440 sci->sc_nfreesegs = argv[4].v_nmembs;
2441 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2442
2443 for (;;) {
2444 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2445 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2446
2447 if (likely(!err))
2448 break;
2449
2450 nilfs_warning(sb, __func__,
2451 "segment construction failed. (err=%d)", err);
2452 set_current_state(TASK_INTERRUPTIBLE);
2453 schedule_timeout(sci->sc_interval);
2454 }
2455 if (nilfs_test_opt(nilfs, DISCARD)) {
2456 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2457 sci->sc_nfreesegs);
2458 if (ret) {
2459 printk(KERN_WARNING
2460 "NILFS warning: error %d on discard request, "
2461 "turning discards off for the device\n", ret);
2462 nilfs_clear_opt(nilfs, DISCARD);
2463 }
2464 }
2465
2466 out_unlock:
2467 sci->sc_freesegs = NULL;
2468 sci->sc_nfreesegs = 0;
2469 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2470 nilfs_transaction_unlock(sb);
2471 return err;
2472}
2473
2474static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2475{
2476 struct nilfs_transaction_info ti;
2477
2478 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2479 nilfs_segctor_construct(sci, mode);
2480
2481 /*
2482 * Unclosed segment should be retried. We do this using sc_timer.
2483 * Timeout of sc_timer will invoke complete construction which leads
2484 * to close the current logical segment.
2485 */
2486 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2487 nilfs_segctor_start_timer(sci);
2488
2489 nilfs_transaction_unlock(sci->sc_super);
2490}
2491
2492static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2493{
2494 int mode = 0;
2495
2496 spin_lock(&sci->sc_state_lock);
2497 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2498 SC_FLUSH_DAT : SC_FLUSH_FILE;
2499 spin_unlock(&sci->sc_state_lock);
2500
2501 if (mode) {
2502 nilfs_segctor_do_construct(sci, mode);
2503
2504 spin_lock(&sci->sc_state_lock);
2505 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2506 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2507 spin_unlock(&sci->sc_state_lock);
2508 }
2509 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2510}
2511
2512static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2513{
2514 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2515 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2516 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2517 return SC_FLUSH_FILE;
2518 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2519 return SC_FLUSH_DAT;
2520 }
2521 return SC_LSEG_SR;
2522}
2523
2524/**
2525 * nilfs_segctor_thread - main loop of the segment constructor thread.
2526 * @arg: pointer to a struct nilfs_sc_info.
2527 *
2528 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2529 * to execute segment constructions.
2530 */
2531static int nilfs_segctor_thread(void *arg)
2532{
2533 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2534 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2535 int timeout = 0;
2536
2537 sci->sc_timer.data = (unsigned long)current;
2538 sci->sc_timer.function = nilfs_construction_timeout;
2539
2540 /* start sync. */
2541 sci->sc_task = current;
2542 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2543 printk(KERN_INFO
2544 "segctord starting. Construction interval = %lu seconds, "
2545 "CP frequency < %lu seconds\n",
2546 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2547
2548 spin_lock(&sci->sc_state_lock);
2549 loop:
2550 for (;;) {
2551 int mode;
2552
2553 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2554 goto end_thread;
2555
2556 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2557 mode = SC_LSEG_SR;
2558 else if (!sci->sc_flush_request)
2559 break;
2560 else
2561 mode = nilfs_segctor_flush_mode(sci);
2562
2563 spin_unlock(&sci->sc_state_lock);
2564 nilfs_segctor_thread_construct(sci, mode);
2565 spin_lock(&sci->sc_state_lock);
2566 timeout = 0;
2567 }
2568
2569
2570 if (freezing(current)) {
2571 spin_unlock(&sci->sc_state_lock);
2572 try_to_freeze();
2573 spin_lock(&sci->sc_state_lock);
2574 } else {
2575 DEFINE_WAIT(wait);
2576 int should_sleep = 1;
2577
2578 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2579 TASK_INTERRUPTIBLE);
2580
2581 if (sci->sc_seq_request != sci->sc_seq_done)
2582 should_sleep = 0;
2583 else if (sci->sc_flush_request)
2584 should_sleep = 0;
2585 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2586 should_sleep = time_before(jiffies,
2587 sci->sc_timer.expires);
2588
2589 if (should_sleep) {
2590 spin_unlock(&sci->sc_state_lock);
2591 schedule();
2592 spin_lock(&sci->sc_state_lock);
2593 }
2594 finish_wait(&sci->sc_wait_daemon, &wait);
2595 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2596 time_after_eq(jiffies, sci->sc_timer.expires));
2597
2598 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2599 set_nilfs_discontinued(nilfs);
2600 }
2601 goto loop;
2602
2603 end_thread:
2604 spin_unlock(&sci->sc_state_lock);
2605
2606 /* end sync. */
2607 sci->sc_task = NULL;
2608 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2609 return 0;
2610}
2611
2612static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2613{
2614 struct task_struct *t;
2615
2616 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2617 if (IS_ERR(t)) {
2618 int err = PTR_ERR(t);
2619
2620 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2621 err);
2622 return err;
2623 }
2624 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2625 return 0;
2626}
2627
2628static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2629 __acquires(&sci->sc_state_lock)
2630 __releases(&sci->sc_state_lock)
2631{
2632 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2633
2634 while (sci->sc_task) {
2635 wake_up(&sci->sc_wait_daemon);
2636 spin_unlock(&sci->sc_state_lock);
2637 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2638 spin_lock(&sci->sc_state_lock);
2639 }
2640}
2641
2642/*
2643 * Setup & clean-up functions
2644 */
2645static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2646 struct nilfs_root *root)
2647{
2648 struct the_nilfs *nilfs = sb->s_fs_info;
2649 struct nilfs_sc_info *sci;
2650
2651 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2652 if (!sci)
2653 return NULL;
2654
2655 sci->sc_super = sb;
2656
2657 nilfs_get_root(root);
2658 sci->sc_root = root;
2659
2660 init_waitqueue_head(&sci->sc_wait_request);
2661 init_waitqueue_head(&sci->sc_wait_daemon);
2662 init_waitqueue_head(&sci->sc_wait_task);
2663 spin_lock_init(&sci->sc_state_lock);
2664 INIT_LIST_HEAD(&sci->sc_dirty_files);
2665 INIT_LIST_HEAD(&sci->sc_segbufs);
2666 INIT_LIST_HEAD(&sci->sc_write_logs);
2667 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2668 INIT_LIST_HEAD(&sci->sc_iput_queue);
2669 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2670 init_timer(&sci->sc_timer);
2671
2672 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2673 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2674 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2675
2676 if (nilfs->ns_interval)
2677 sci->sc_interval = HZ * nilfs->ns_interval;
2678 if (nilfs->ns_watermark)
2679 sci->sc_watermark = nilfs->ns_watermark;
2680 return sci;
2681}
2682
2683static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2684{
2685 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2686
2687 /* The segctord thread was stopped and its timer was removed.
2688 But some tasks remain. */
2689 do {
2690 struct nilfs_transaction_info ti;
2691
2692 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2693 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2694 nilfs_transaction_unlock(sci->sc_super);
2695
2696 flush_work(&sci->sc_iput_work);
2697
2698 } while (ret && retrycount-- > 0);
2699}
2700
2701/**
2702 * nilfs_segctor_destroy - destroy the segment constructor.
2703 * @sci: nilfs_sc_info
2704 *
2705 * nilfs_segctor_destroy() kills the segctord thread and frees
2706 * the nilfs_sc_info struct.
2707 * Caller must hold the segment semaphore.
2708 */
2709static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2710{
2711 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2712 int flag;
2713
2714 up_write(&nilfs->ns_segctor_sem);
2715
2716 spin_lock(&sci->sc_state_lock);
2717 nilfs_segctor_kill_thread(sci);
2718 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2719 || sci->sc_seq_request != sci->sc_seq_done);
2720 spin_unlock(&sci->sc_state_lock);
2721
2722 if (flush_work(&sci->sc_iput_work))
2723 flag = true;
2724
2725 if (flag || !nilfs_segctor_confirm(sci))
2726 nilfs_segctor_write_out(sci);
2727
2728 if (!list_empty(&sci->sc_dirty_files)) {
2729 nilfs_warning(sci->sc_super, __func__,
2730 "dirty file(s) after the final construction\n");
2731 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2732 }
2733
2734 if (!list_empty(&sci->sc_iput_queue)) {
2735 nilfs_warning(sci->sc_super, __func__,
2736 "iput queue is not empty\n");
2737 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2738 }
2739
2740 WARN_ON(!list_empty(&sci->sc_segbufs));
2741 WARN_ON(!list_empty(&sci->sc_write_logs));
2742
2743 nilfs_put_root(sci->sc_root);
2744
2745 down_write(&nilfs->ns_segctor_sem);
2746
2747 del_timer_sync(&sci->sc_timer);
2748 kfree(sci);
2749}
2750
2751/**
2752 * nilfs_attach_log_writer - attach log writer
2753 * @sb: super block instance
2754 * @root: root object of the current filesystem tree
2755 *
2756 * This allocates a log writer object, initializes it, and starts the
2757 * log writer.
2758 *
2759 * Return Value: On success, 0 is returned. On error, one of the following
2760 * negative error code is returned.
2761 *
2762 * %-ENOMEM - Insufficient memory available.
2763 */
2764int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2765{
2766 struct the_nilfs *nilfs = sb->s_fs_info;
2767 int err;
2768
2769 if (nilfs->ns_writer) {
2770 /*
2771 * This happens if the filesystem was remounted
2772 * read/write after nilfs_error degenerated it into a
2773 * read-only mount.
2774 */
2775 nilfs_detach_log_writer(sb);
2776 }
2777
2778 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2779 if (!nilfs->ns_writer)
2780 return -ENOMEM;
2781
2782 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2783 if (err) {
2784 kfree(nilfs->ns_writer);
2785 nilfs->ns_writer = NULL;
2786 }
2787 return err;
2788}
2789
2790/**
2791 * nilfs_detach_log_writer - destroy log writer
2792 * @sb: super block instance
2793 *
2794 * This kills log writer daemon, frees the log writer object, and
2795 * destroys list of dirty files.
2796 */
2797void nilfs_detach_log_writer(struct super_block *sb)
2798{
2799 struct the_nilfs *nilfs = sb->s_fs_info;
2800 LIST_HEAD(garbage_list);
2801
2802 down_write(&nilfs->ns_segctor_sem);
2803 if (nilfs->ns_writer) {
2804 nilfs_segctor_destroy(nilfs->ns_writer);
2805 nilfs->ns_writer = NULL;
2806 }
2807
2808 /* Force to free the list of dirty files */
2809 spin_lock(&nilfs->ns_inode_lock);
2810 if (!list_empty(&nilfs->ns_dirty_files)) {
2811 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2812 nilfs_warning(sb, __func__,
2813 "Hit dirty file after stopped log writer\n");
2814 }
2815 spin_unlock(&nilfs->ns_inode_lock);
2816 up_write(&nilfs->ns_segctor_sem);
2817
2818 nilfs_dispose_list(nilfs, &garbage_list, 1);
2819}