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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 * Written by Ryusuke Konishi.
17 *
18 */
19
20#include <linux/pagemap.h>
21#include <linux/buffer_head.h>
22#include <linux/writeback.h>
23#include <linux/bitops.h>
24#include <linux/bio.h>
25#include <linux/completion.h>
26#include <linux/blkdev.h>
27#include <linux/backing-dev.h>
28#include <linux/freezer.h>
29#include <linux/kthread.h>
30#include <linux/crc32.h>
31#include <linux/pagevec.h>
32#include <linux/slab.h>
33#include <linux/sched/signal.h>
34
35#include "nilfs.h"
36#include "btnode.h"
37#include "page.h"
38#include "segment.h"
39#include "sufile.h"
40#include "cpfile.h"
41#include "ifile.h"
42#include "segbuf.h"
43
44
45/*
46 * Segment constructor
47 */
48#define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
49
50#define SC_MAX_SEGDELTA 64 /*
51 * Upper limit of the number of segments
52 * appended in collection retry loop
53 */
54
55/* Construction mode */
56enum {
57 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
58 SC_LSEG_DSYNC, /*
59 * Flush data blocks of a given file and make
60 * a logical segment without a super root.
61 */
62 SC_FLUSH_FILE, /*
63 * Flush data files, leads to segment writes without
64 * creating a checkpoint.
65 */
66 SC_FLUSH_DAT, /*
67 * Flush DAT file. This also creates segments
68 * without a checkpoint.
69 */
70};
71
72/* Stage numbers of dirty block collection */
73enum {
74 NILFS_ST_INIT = 0,
75 NILFS_ST_GC, /* Collecting dirty blocks for GC */
76 NILFS_ST_FILE,
77 NILFS_ST_IFILE,
78 NILFS_ST_CPFILE,
79 NILFS_ST_SUFILE,
80 NILFS_ST_DAT,
81 NILFS_ST_SR, /* Super root */
82 NILFS_ST_DSYNC, /* Data sync blocks */
83 NILFS_ST_DONE,
84};
85
86#define CREATE_TRACE_POINTS
87#include <trace/events/nilfs2.h>
88
89/*
90 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
91 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
92 * the variable must use them because transition of stage count must involve
93 * trace events (trace_nilfs2_collection_stage_transition).
94 *
95 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
96 * produce tracepoint events. It is provided just for making the intention
97 * clear.
98 */
99static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
100{
101 sci->sc_stage.scnt++;
102 trace_nilfs2_collection_stage_transition(sci);
103}
104
105static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
106{
107 sci->sc_stage.scnt = next_scnt;
108 trace_nilfs2_collection_stage_transition(sci);
109}
110
111static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
112{
113 return sci->sc_stage.scnt;
114}
115
116/* State flags of collection */
117#define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
118#define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
119#define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
120#define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
121
122/* Operations depending on the construction mode and file type */
123struct nilfs_sc_operations {
124 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
125 struct inode *);
126 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
127 struct inode *);
128 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
129 struct inode *);
130 void (*write_data_binfo)(struct nilfs_sc_info *,
131 struct nilfs_segsum_pointer *,
132 union nilfs_binfo *);
133 void (*write_node_binfo)(struct nilfs_sc_info *,
134 struct nilfs_segsum_pointer *,
135 union nilfs_binfo *);
136};
137
138/*
139 * Other definitions
140 */
141static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
142static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
143static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
144static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
145
146#define nilfs_cnt32_gt(a, b) \
147 (typecheck(__u32, a) && typecheck(__u32, b) && \
148 ((__s32)(b) - (__s32)(a) < 0))
149#define nilfs_cnt32_ge(a, b) \
150 (typecheck(__u32, a) && typecheck(__u32, b) && \
151 ((__s32)(a) - (__s32)(b) >= 0))
152#define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
153#define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
154
155static int nilfs_prepare_segment_lock(struct super_block *sb,
156 struct nilfs_transaction_info *ti)
157{
158 struct nilfs_transaction_info *cur_ti = current->journal_info;
159 void *save = NULL;
160
161 if (cur_ti) {
162 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
163 return ++cur_ti->ti_count;
164
165 /*
166 * If journal_info field is occupied by other FS,
167 * it is saved and will be restored on
168 * nilfs_transaction_commit().
169 */
170 nilfs_msg(sb, KERN_WARNING, "journal info from a different FS");
171 save = current->journal_info;
172 }
173 if (!ti) {
174 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
175 if (!ti)
176 return -ENOMEM;
177 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
178 } else {
179 ti->ti_flags = 0;
180 }
181 ti->ti_count = 0;
182 ti->ti_save = save;
183 ti->ti_magic = NILFS_TI_MAGIC;
184 current->journal_info = ti;
185 return 0;
186}
187
188/**
189 * nilfs_transaction_begin - start indivisible file operations.
190 * @sb: super block
191 * @ti: nilfs_transaction_info
192 * @vacancy_check: flags for vacancy rate checks
193 *
194 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
195 * the segment semaphore, to make a segment construction and write tasks
196 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
197 * The region enclosed by these two functions can be nested. To avoid a
198 * deadlock, the semaphore is only acquired or released in the outermost call.
199 *
200 * This function allocates a nilfs_transaction_info struct to keep context
201 * information on it. It is initialized and hooked onto the current task in
202 * the outermost call. If a pre-allocated struct is given to @ti, it is used
203 * instead; otherwise a new struct is assigned from a slab.
204 *
205 * When @vacancy_check flag is set, this function will check the amount of
206 * free space, and will wait for the GC to reclaim disk space if low capacity.
207 *
208 * Return Value: On success, 0 is returned. On error, one of the following
209 * negative error code is returned.
210 *
211 * %-ENOMEM - Insufficient memory available.
212 *
213 * %-ENOSPC - No space left on device
214 */
215int nilfs_transaction_begin(struct super_block *sb,
216 struct nilfs_transaction_info *ti,
217 int vacancy_check)
218{
219 struct the_nilfs *nilfs;
220 int ret = nilfs_prepare_segment_lock(sb, ti);
221 struct nilfs_transaction_info *trace_ti;
222
223 if (unlikely(ret < 0))
224 return ret;
225 if (ret > 0) {
226 trace_ti = current->journal_info;
227
228 trace_nilfs2_transaction_transition(sb, trace_ti,
229 trace_ti->ti_count, trace_ti->ti_flags,
230 TRACE_NILFS2_TRANSACTION_BEGIN);
231 return 0;
232 }
233
234 sb_start_intwrite(sb);
235
236 nilfs = sb->s_fs_info;
237 down_read(&nilfs->ns_segctor_sem);
238 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
239 up_read(&nilfs->ns_segctor_sem);
240 ret = -ENOSPC;
241 goto failed;
242 }
243
244 trace_ti = current->journal_info;
245 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
246 trace_ti->ti_flags,
247 TRACE_NILFS2_TRANSACTION_BEGIN);
248 return 0;
249
250 failed:
251 ti = current->journal_info;
252 current->journal_info = ti->ti_save;
253 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
254 kmem_cache_free(nilfs_transaction_cachep, ti);
255 sb_end_intwrite(sb);
256 return ret;
257}
258
259/**
260 * nilfs_transaction_commit - commit indivisible file operations.
261 * @sb: super block
262 *
263 * nilfs_transaction_commit() releases the read semaphore which is
264 * acquired by nilfs_transaction_begin(). This is only performed
265 * in outermost call of this function. If a commit flag is set,
266 * nilfs_transaction_commit() sets a timer to start the segment
267 * constructor. If a sync flag is set, it starts construction
268 * directly.
269 */
270int nilfs_transaction_commit(struct super_block *sb)
271{
272 struct nilfs_transaction_info *ti = current->journal_info;
273 struct the_nilfs *nilfs = sb->s_fs_info;
274 int err = 0;
275
276 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
277 ti->ti_flags |= NILFS_TI_COMMIT;
278 if (ti->ti_count > 0) {
279 ti->ti_count--;
280 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
281 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
282 return 0;
283 }
284 if (nilfs->ns_writer) {
285 struct nilfs_sc_info *sci = nilfs->ns_writer;
286
287 if (ti->ti_flags & NILFS_TI_COMMIT)
288 nilfs_segctor_start_timer(sci);
289 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
290 nilfs_segctor_do_flush(sci, 0);
291 }
292 up_read(&nilfs->ns_segctor_sem);
293 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
294 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
295
296 current->journal_info = ti->ti_save;
297
298 if (ti->ti_flags & NILFS_TI_SYNC)
299 err = nilfs_construct_segment(sb);
300 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
301 kmem_cache_free(nilfs_transaction_cachep, ti);
302 sb_end_intwrite(sb);
303 return err;
304}
305
306void nilfs_transaction_abort(struct super_block *sb)
307{
308 struct nilfs_transaction_info *ti = current->journal_info;
309 struct the_nilfs *nilfs = sb->s_fs_info;
310
311 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
312 if (ti->ti_count > 0) {
313 ti->ti_count--;
314 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
315 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
316 return;
317 }
318 up_read(&nilfs->ns_segctor_sem);
319
320 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
321 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
322
323 current->journal_info = ti->ti_save;
324 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
325 kmem_cache_free(nilfs_transaction_cachep, ti);
326 sb_end_intwrite(sb);
327}
328
329void nilfs_relax_pressure_in_lock(struct super_block *sb)
330{
331 struct the_nilfs *nilfs = sb->s_fs_info;
332 struct nilfs_sc_info *sci = nilfs->ns_writer;
333
334 if (!sci || !sci->sc_flush_request)
335 return;
336
337 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
338 up_read(&nilfs->ns_segctor_sem);
339
340 down_write(&nilfs->ns_segctor_sem);
341 if (sci->sc_flush_request &&
342 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
343 struct nilfs_transaction_info *ti = current->journal_info;
344
345 ti->ti_flags |= NILFS_TI_WRITER;
346 nilfs_segctor_do_immediate_flush(sci);
347 ti->ti_flags &= ~NILFS_TI_WRITER;
348 }
349 downgrade_write(&nilfs->ns_segctor_sem);
350}
351
352static void nilfs_transaction_lock(struct super_block *sb,
353 struct nilfs_transaction_info *ti,
354 int gcflag)
355{
356 struct nilfs_transaction_info *cur_ti = current->journal_info;
357 struct the_nilfs *nilfs = sb->s_fs_info;
358 struct nilfs_sc_info *sci = nilfs->ns_writer;
359
360 WARN_ON(cur_ti);
361 ti->ti_flags = NILFS_TI_WRITER;
362 ti->ti_count = 0;
363 ti->ti_save = cur_ti;
364 ti->ti_magic = NILFS_TI_MAGIC;
365 current->journal_info = ti;
366
367 for (;;) {
368 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
369 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
370
371 down_write(&nilfs->ns_segctor_sem);
372 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
373 break;
374
375 nilfs_segctor_do_immediate_flush(sci);
376
377 up_write(&nilfs->ns_segctor_sem);
378 cond_resched();
379 }
380 if (gcflag)
381 ti->ti_flags |= NILFS_TI_GC;
382
383 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
384 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
385}
386
387static void nilfs_transaction_unlock(struct super_block *sb)
388{
389 struct nilfs_transaction_info *ti = current->journal_info;
390 struct the_nilfs *nilfs = sb->s_fs_info;
391
392 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
393 BUG_ON(ti->ti_count > 0);
394
395 up_write(&nilfs->ns_segctor_sem);
396 current->journal_info = ti->ti_save;
397
398 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
399 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
400}
401
402static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
403 struct nilfs_segsum_pointer *ssp,
404 unsigned int bytes)
405{
406 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
407 unsigned int blocksize = sci->sc_super->s_blocksize;
408 void *p;
409
410 if (unlikely(ssp->offset + bytes > blocksize)) {
411 ssp->offset = 0;
412 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
413 &segbuf->sb_segsum_buffers));
414 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
415 }
416 p = ssp->bh->b_data + ssp->offset;
417 ssp->offset += bytes;
418 return p;
419}
420
421/**
422 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
423 * @sci: nilfs_sc_info
424 */
425static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
426{
427 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
428 struct buffer_head *sumbh;
429 unsigned int sumbytes;
430 unsigned int flags = 0;
431 int err;
432
433 if (nilfs_doing_gc())
434 flags = NILFS_SS_GC;
435 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
436 if (unlikely(err))
437 return err;
438
439 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
440 sumbytes = segbuf->sb_sum.sumbytes;
441 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
442 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
443 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
444 return 0;
445}
446
447static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
448{
449 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
450 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
451 return -E2BIG; /*
452 * The current segment is filled up
453 * (internal code)
454 */
455 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
456 return nilfs_segctor_reset_segment_buffer(sci);
457}
458
459static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
460{
461 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
462 int err;
463
464 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
465 err = nilfs_segctor_feed_segment(sci);
466 if (err)
467 return err;
468 segbuf = sci->sc_curseg;
469 }
470 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
471 if (likely(!err))
472 segbuf->sb_sum.flags |= NILFS_SS_SR;
473 return err;
474}
475
476/*
477 * Functions for making segment summary and payloads
478 */
479static int nilfs_segctor_segsum_block_required(
480 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
481 unsigned int binfo_size)
482{
483 unsigned int blocksize = sci->sc_super->s_blocksize;
484 /* Size of finfo and binfo is enough small against blocksize */
485
486 return ssp->offset + binfo_size +
487 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
488 blocksize;
489}
490
491static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
492 struct inode *inode)
493{
494 sci->sc_curseg->sb_sum.nfinfo++;
495 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
496 nilfs_segctor_map_segsum_entry(
497 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
498
499 if (NILFS_I(inode)->i_root &&
500 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
501 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
502 /* skip finfo */
503}
504
505static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
506 struct inode *inode)
507{
508 struct nilfs_finfo *finfo;
509 struct nilfs_inode_info *ii;
510 struct nilfs_segment_buffer *segbuf;
511 __u64 cno;
512
513 if (sci->sc_blk_cnt == 0)
514 return;
515
516 ii = NILFS_I(inode);
517
518 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
519 cno = ii->i_cno;
520 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
521 cno = 0;
522 else
523 cno = sci->sc_cno;
524
525 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
526 sizeof(*finfo));
527 finfo->fi_ino = cpu_to_le64(inode->i_ino);
528 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
529 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
530 finfo->fi_cno = cpu_to_le64(cno);
531
532 segbuf = sci->sc_curseg;
533 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
534 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
535 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
536 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
537}
538
539static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
540 struct buffer_head *bh,
541 struct inode *inode,
542 unsigned int binfo_size)
543{
544 struct nilfs_segment_buffer *segbuf;
545 int required, err = 0;
546
547 retry:
548 segbuf = sci->sc_curseg;
549 required = nilfs_segctor_segsum_block_required(
550 sci, &sci->sc_binfo_ptr, binfo_size);
551 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
552 nilfs_segctor_end_finfo(sci, inode);
553 err = nilfs_segctor_feed_segment(sci);
554 if (err)
555 return err;
556 goto retry;
557 }
558 if (unlikely(required)) {
559 err = nilfs_segbuf_extend_segsum(segbuf);
560 if (unlikely(err))
561 goto failed;
562 }
563 if (sci->sc_blk_cnt == 0)
564 nilfs_segctor_begin_finfo(sci, inode);
565
566 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
567 /* Substitution to vblocknr is delayed until update_blocknr() */
568 nilfs_segbuf_add_file_buffer(segbuf, bh);
569 sci->sc_blk_cnt++;
570 failed:
571 return err;
572}
573
574/*
575 * Callback functions that enumerate, mark, and collect dirty blocks
576 */
577static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
578 struct buffer_head *bh, struct inode *inode)
579{
580 int err;
581
582 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
583 if (err < 0)
584 return err;
585
586 err = nilfs_segctor_add_file_block(sci, bh, inode,
587 sizeof(struct nilfs_binfo_v));
588 if (!err)
589 sci->sc_datablk_cnt++;
590 return err;
591}
592
593static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
594 struct buffer_head *bh,
595 struct inode *inode)
596{
597 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
598}
599
600static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
601 struct buffer_head *bh,
602 struct inode *inode)
603{
604 WARN_ON(!buffer_dirty(bh));
605 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
606}
607
608static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
609 struct nilfs_segsum_pointer *ssp,
610 union nilfs_binfo *binfo)
611{
612 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
613 sci, ssp, sizeof(*binfo_v));
614 *binfo_v = binfo->bi_v;
615}
616
617static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
618 struct nilfs_segsum_pointer *ssp,
619 union nilfs_binfo *binfo)
620{
621 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
622 sci, ssp, sizeof(*vblocknr));
623 *vblocknr = binfo->bi_v.bi_vblocknr;
624}
625
626static const struct nilfs_sc_operations nilfs_sc_file_ops = {
627 .collect_data = nilfs_collect_file_data,
628 .collect_node = nilfs_collect_file_node,
629 .collect_bmap = nilfs_collect_file_bmap,
630 .write_data_binfo = nilfs_write_file_data_binfo,
631 .write_node_binfo = nilfs_write_file_node_binfo,
632};
633
634static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
635 struct buffer_head *bh, struct inode *inode)
636{
637 int err;
638
639 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
640 if (err < 0)
641 return err;
642
643 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
644 if (!err)
645 sci->sc_datablk_cnt++;
646 return err;
647}
648
649static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
650 struct buffer_head *bh, struct inode *inode)
651{
652 WARN_ON(!buffer_dirty(bh));
653 return nilfs_segctor_add_file_block(sci, bh, inode,
654 sizeof(struct nilfs_binfo_dat));
655}
656
657static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
658 struct nilfs_segsum_pointer *ssp,
659 union nilfs_binfo *binfo)
660{
661 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
662 sizeof(*blkoff));
663 *blkoff = binfo->bi_dat.bi_blkoff;
664}
665
666static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
667 struct nilfs_segsum_pointer *ssp,
668 union nilfs_binfo *binfo)
669{
670 struct nilfs_binfo_dat *binfo_dat =
671 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
672 *binfo_dat = binfo->bi_dat;
673}
674
675static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
676 .collect_data = nilfs_collect_dat_data,
677 .collect_node = nilfs_collect_file_node,
678 .collect_bmap = nilfs_collect_dat_bmap,
679 .write_data_binfo = nilfs_write_dat_data_binfo,
680 .write_node_binfo = nilfs_write_dat_node_binfo,
681};
682
683static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
684 .collect_data = nilfs_collect_file_data,
685 .collect_node = NULL,
686 .collect_bmap = NULL,
687 .write_data_binfo = nilfs_write_file_data_binfo,
688 .write_node_binfo = NULL,
689};
690
691static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
692 struct list_head *listp,
693 size_t nlimit,
694 loff_t start, loff_t end)
695{
696 struct address_space *mapping = inode->i_mapping;
697 struct pagevec pvec;
698 pgoff_t index = 0, last = ULONG_MAX;
699 size_t ndirties = 0;
700 int i;
701
702 if (unlikely(start != 0 || end != LLONG_MAX)) {
703 /*
704 * A valid range is given for sync-ing data pages. The
705 * range is rounded to per-page; extra dirty buffers
706 * may be included if blocksize < pagesize.
707 */
708 index = start >> PAGE_SHIFT;
709 last = end >> PAGE_SHIFT;
710 }
711 pagevec_init(&pvec);
712 repeat:
713 if (unlikely(index > last) ||
714 !pagevec_lookup_range_tag(&pvec, mapping, &index, last,
715 PAGECACHE_TAG_DIRTY))
716 return ndirties;
717
718 for (i = 0; i < pagevec_count(&pvec); i++) {
719 struct buffer_head *bh, *head;
720 struct page *page = pvec.pages[i];
721
722 lock_page(page);
723 if (!page_has_buffers(page))
724 create_empty_buffers(page, i_blocksize(inode), 0);
725 unlock_page(page);
726
727 bh = head = page_buffers(page);
728 do {
729 if (!buffer_dirty(bh) || buffer_async_write(bh))
730 continue;
731 get_bh(bh);
732 list_add_tail(&bh->b_assoc_buffers, listp);
733 ndirties++;
734 if (unlikely(ndirties >= nlimit)) {
735 pagevec_release(&pvec);
736 cond_resched();
737 return ndirties;
738 }
739 } while (bh = bh->b_this_page, bh != head);
740 }
741 pagevec_release(&pvec);
742 cond_resched();
743 goto repeat;
744}
745
746static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
747 struct list_head *listp)
748{
749 struct nilfs_inode_info *ii = NILFS_I(inode);
750 struct address_space *mapping = &ii->i_btnode_cache;
751 struct pagevec pvec;
752 struct buffer_head *bh, *head;
753 unsigned int i;
754 pgoff_t index = 0;
755
756 pagevec_init(&pvec);
757
758 while (pagevec_lookup_tag(&pvec, mapping, &index,
759 PAGECACHE_TAG_DIRTY)) {
760 for (i = 0; i < pagevec_count(&pvec); i++) {
761 bh = head = page_buffers(pvec.pages[i]);
762 do {
763 if (buffer_dirty(bh) &&
764 !buffer_async_write(bh)) {
765 get_bh(bh);
766 list_add_tail(&bh->b_assoc_buffers,
767 listp);
768 }
769 bh = bh->b_this_page;
770 } while (bh != head);
771 }
772 pagevec_release(&pvec);
773 cond_resched();
774 }
775}
776
777static void nilfs_dispose_list(struct the_nilfs *nilfs,
778 struct list_head *head, int force)
779{
780 struct nilfs_inode_info *ii, *n;
781 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
782 unsigned int nv = 0;
783
784 while (!list_empty(head)) {
785 spin_lock(&nilfs->ns_inode_lock);
786 list_for_each_entry_safe(ii, n, head, i_dirty) {
787 list_del_init(&ii->i_dirty);
788 if (force) {
789 if (unlikely(ii->i_bh)) {
790 brelse(ii->i_bh);
791 ii->i_bh = NULL;
792 }
793 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
794 set_bit(NILFS_I_QUEUED, &ii->i_state);
795 list_add_tail(&ii->i_dirty,
796 &nilfs->ns_dirty_files);
797 continue;
798 }
799 ivec[nv++] = ii;
800 if (nv == SC_N_INODEVEC)
801 break;
802 }
803 spin_unlock(&nilfs->ns_inode_lock);
804
805 for (pii = ivec; nv > 0; pii++, nv--)
806 iput(&(*pii)->vfs_inode);
807 }
808}
809
810static void nilfs_iput_work_func(struct work_struct *work)
811{
812 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
813 sc_iput_work);
814 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
815
816 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
817}
818
819static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
820 struct nilfs_root *root)
821{
822 int ret = 0;
823
824 if (nilfs_mdt_fetch_dirty(root->ifile))
825 ret++;
826 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
827 ret++;
828 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
829 ret++;
830 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
831 ret++;
832 return ret;
833}
834
835static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
836{
837 return list_empty(&sci->sc_dirty_files) &&
838 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
839 sci->sc_nfreesegs == 0 &&
840 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
841}
842
843static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
844{
845 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
846 int ret = 0;
847
848 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
849 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
850
851 spin_lock(&nilfs->ns_inode_lock);
852 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
853 ret++;
854
855 spin_unlock(&nilfs->ns_inode_lock);
856 return ret;
857}
858
859static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
860{
861 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
862
863 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
864 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
865 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
866 nilfs_mdt_clear_dirty(nilfs->ns_dat);
867}
868
869static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
870{
871 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
872 struct buffer_head *bh_cp;
873 struct nilfs_checkpoint *raw_cp;
874 int err;
875
876 /* XXX: this interface will be changed */
877 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
878 &raw_cp, &bh_cp);
879 if (likely(!err)) {
880 /*
881 * The following code is duplicated with cpfile. But, it is
882 * needed to collect the checkpoint even if it was not newly
883 * created.
884 */
885 mark_buffer_dirty(bh_cp);
886 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
887 nilfs_cpfile_put_checkpoint(
888 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
889 } else
890 WARN_ON(err == -EINVAL || err == -ENOENT);
891
892 return err;
893}
894
895static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
896{
897 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
898 struct buffer_head *bh_cp;
899 struct nilfs_checkpoint *raw_cp;
900 int err;
901
902 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
903 &raw_cp, &bh_cp);
904 if (unlikely(err)) {
905 WARN_ON(err == -EINVAL || err == -ENOENT);
906 goto failed_ibh;
907 }
908 raw_cp->cp_snapshot_list.ssl_next = 0;
909 raw_cp->cp_snapshot_list.ssl_prev = 0;
910 raw_cp->cp_inodes_count =
911 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
912 raw_cp->cp_blocks_count =
913 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
914 raw_cp->cp_nblk_inc =
915 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
916 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
917 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
918
919 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
920 nilfs_checkpoint_clear_minor(raw_cp);
921 else
922 nilfs_checkpoint_set_minor(raw_cp);
923
924 nilfs_write_inode_common(sci->sc_root->ifile,
925 &raw_cp->cp_ifile_inode, 1);
926 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
927 return 0;
928
929 failed_ibh:
930 return err;
931}
932
933static void nilfs_fill_in_file_bmap(struct inode *ifile,
934 struct nilfs_inode_info *ii)
935
936{
937 struct buffer_head *ibh;
938 struct nilfs_inode *raw_inode;
939
940 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
941 ibh = ii->i_bh;
942 BUG_ON(!ibh);
943 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
944 ibh);
945 nilfs_bmap_write(ii->i_bmap, raw_inode);
946 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
947 }
948}
949
950static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
951{
952 struct nilfs_inode_info *ii;
953
954 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
955 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
956 set_bit(NILFS_I_COLLECTED, &ii->i_state);
957 }
958}
959
960static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
961 struct the_nilfs *nilfs)
962{
963 struct buffer_head *bh_sr;
964 struct nilfs_super_root *raw_sr;
965 unsigned int isz, srsz;
966
967 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
968 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
969 isz = nilfs->ns_inode_size;
970 srsz = NILFS_SR_BYTES(isz);
971
972 raw_sr->sr_bytes = cpu_to_le16(srsz);
973 raw_sr->sr_nongc_ctime
974 = cpu_to_le64(nilfs_doing_gc() ?
975 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
976 raw_sr->sr_flags = 0;
977
978 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
979 NILFS_SR_DAT_OFFSET(isz), 1);
980 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
981 NILFS_SR_CPFILE_OFFSET(isz), 1);
982 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
983 NILFS_SR_SUFILE_OFFSET(isz), 1);
984 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
985}
986
987static void nilfs_redirty_inodes(struct list_head *head)
988{
989 struct nilfs_inode_info *ii;
990
991 list_for_each_entry(ii, head, i_dirty) {
992 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
993 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
994 }
995}
996
997static void nilfs_drop_collected_inodes(struct list_head *head)
998{
999 struct nilfs_inode_info *ii;
1000
1001 list_for_each_entry(ii, head, i_dirty) {
1002 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
1003 continue;
1004
1005 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
1006 set_bit(NILFS_I_UPDATED, &ii->i_state);
1007 }
1008}
1009
1010static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1011 struct inode *inode,
1012 struct list_head *listp,
1013 int (*collect)(struct nilfs_sc_info *,
1014 struct buffer_head *,
1015 struct inode *))
1016{
1017 struct buffer_head *bh, *n;
1018 int err = 0;
1019
1020 if (collect) {
1021 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1022 list_del_init(&bh->b_assoc_buffers);
1023 err = collect(sci, bh, inode);
1024 brelse(bh);
1025 if (unlikely(err))
1026 goto dispose_buffers;
1027 }
1028 return 0;
1029 }
1030
1031 dispose_buffers:
1032 while (!list_empty(listp)) {
1033 bh = list_first_entry(listp, struct buffer_head,
1034 b_assoc_buffers);
1035 list_del_init(&bh->b_assoc_buffers);
1036 brelse(bh);
1037 }
1038 return err;
1039}
1040
1041static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1042{
1043 /* Remaining number of blocks within segment buffer */
1044 return sci->sc_segbuf_nblocks -
1045 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1046}
1047
1048static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1049 struct inode *inode,
1050 const struct nilfs_sc_operations *sc_ops)
1051{
1052 LIST_HEAD(data_buffers);
1053 LIST_HEAD(node_buffers);
1054 int err;
1055
1056 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1057 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1058
1059 n = nilfs_lookup_dirty_data_buffers(
1060 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1061 if (n > rest) {
1062 err = nilfs_segctor_apply_buffers(
1063 sci, inode, &data_buffers,
1064 sc_ops->collect_data);
1065 BUG_ON(!err); /* always receive -E2BIG or true error */
1066 goto break_or_fail;
1067 }
1068 }
1069 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1070
1071 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1072 err = nilfs_segctor_apply_buffers(
1073 sci, inode, &data_buffers, sc_ops->collect_data);
1074 if (unlikely(err)) {
1075 /* dispose node list */
1076 nilfs_segctor_apply_buffers(
1077 sci, inode, &node_buffers, NULL);
1078 goto break_or_fail;
1079 }
1080 sci->sc_stage.flags |= NILFS_CF_NODE;
1081 }
1082 /* Collect node */
1083 err = nilfs_segctor_apply_buffers(
1084 sci, inode, &node_buffers, sc_ops->collect_node);
1085 if (unlikely(err))
1086 goto break_or_fail;
1087
1088 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1089 err = nilfs_segctor_apply_buffers(
1090 sci, inode, &node_buffers, sc_ops->collect_bmap);
1091 if (unlikely(err))
1092 goto break_or_fail;
1093
1094 nilfs_segctor_end_finfo(sci, inode);
1095 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1096
1097 break_or_fail:
1098 return err;
1099}
1100
1101static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1102 struct inode *inode)
1103{
1104 LIST_HEAD(data_buffers);
1105 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1106 int err;
1107
1108 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1109 sci->sc_dsync_start,
1110 sci->sc_dsync_end);
1111
1112 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1113 nilfs_collect_file_data);
1114 if (!err) {
1115 nilfs_segctor_end_finfo(sci, inode);
1116 BUG_ON(n > rest);
1117 /* always receive -E2BIG or true error if n > rest */
1118 }
1119 return err;
1120}
1121
1122static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1123{
1124 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1125 struct list_head *head;
1126 struct nilfs_inode_info *ii;
1127 size_t ndone;
1128 int err = 0;
1129
1130 switch (nilfs_sc_cstage_get(sci)) {
1131 case NILFS_ST_INIT:
1132 /* Pre-processes */
1133 sci->sc_stage.flags = 0;
1134
1135 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1136 sci->sc_nblk_inc = 0;
1137 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1138 if (mode == SC_LSEG_DSYNC) {
1139 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1140 goto dsync_mode;
1141 }
1142 }
1143
1144 sci->sc_stage.dirty_file_ptr = NULL;
1145 sci->sc_stage.gc_inode_ptr = NULL;
1146 if (mode == SC_FLUSH_DAT) {
1147 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1148 goto dat_stage;
1149 }
1150 nilfs_sc_cstage_inc(sci); /* Fall through */
1151 case NILFS_ST_GC:
1152 if (nilfs_doing_gc()) {
1153 head = &sci->sc_gc_inodes;
1154 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1155 head, i_dirty);
1156 list_for_each_entry_continue(ii, head, i_dirty) {
1157 err = nilfs_segctor_scan_file(
1158 sci, &ii->vfs_inode,
1159 &nilfs_sc_file_ops);
1160 if (unlikely(err)) {
1161 sci->sc_stage.gc_inode_ptr = list_entry(
1162 ii->i_dirty.prev,
1163 struct nilfs_inode_info,
1164 i_dirty);
1165 goto break_or_fail;
1166 }
1167 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1168 }
1169 sci->sc_stage.gc_inode_ptr = NULL;
1170 }
1171 nilfs_sc_cstage_inc(sci); /* Fall through */
1172 case NILFS_ST_FILE:
1173 head = &sci->sc_dirty_files;
1174 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1175 i_dirty);
1176 list_for_each_entry_continue(ii, head, i_dirty) {
1177 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1178
1179 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1180 &nilfs_sc_file_ops);
1181 if (unlikely(err)) {
1182 sci->sc_stage.dirty_file_ptr =
1183 list_entry(ii->i_dirty.prev,
1184 struct nilfs_inode_info,
1185 i_dirty);
1186 goto break_or_fail;
1187 }
1188 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1189 /* XXX: required ? */
1190 }
1191 sci->sc_stage.dirty_file_ptr = NULL;
1192 if (mode == SC_FLUSH_FILE) {
1193 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1194 return 0;
1195 }
1196 nilfs_sc_cstage_inc(sci);
1197 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1198 /* Fall through */
1199 case NILFS_ST_IFILE:
1200 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1201 &nilfs_sc_file_ops);
1202 if (unlikely(err))
1203 break;
1204 nilfs_sc_cstage_inc(sci);
1205 /* Creating a checkpoint */
1206 err = nilfs_segctor_create_checkpoint(sci);
1207 if (unlikely(err))
1208 break;
1209 /* Fall through */
1210 case NILFS_ST_CPFILE:
1211 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1212 &nilfs_sc_file_ops);
1213 if (unlikely(err))
1214 break;
1215 nilfs_sc_cstage_inc(sci); /* Fall through */
1216 case NILFS_ST_SUFILE:
1217 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1218 sci->sc_nfreesegs, &ndone);
1219 if (unlikely(err)) {
1220 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1221 sci->sc_freesegs, ndone,
1222 NULL);
1223 break;
1224 }
1225 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1226
1227 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1228 &nilfs_sc_file_ops);
1229 if (unlikely(err))
1230 break;
1231 nilfs_sc_cstage_inc(sci); /* Fall through */
1232 case NILFS_ST_DAT:
1233 dat_stage:
1234 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1235 &nilfs_sc_dat_ops);
1236 if (unlikely(err))
1237 break;
1238 if (mode == SC_FLUSH_DAT) {
1239 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1240 return 0;
1241 }
1242 nilfs_sc_cstage_inc(sci); /* Fall through */
1243 case NILFS_ST_SR:
1244 if (mode == SC_LSEG_SR) {
1245 /* Appending a super root */
1246 err = nilfs_segctor_add_super_root(sci);
1247 if (unlikely(err))
1248 break;
1249 }
1250 /* End of a logical segment */
1251 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1252 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1253 return 0;
1254 case NILFS_ST_DSYNC:
1255 dsync_mode:
1256 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1257 ii = sci->sc_dsync_inode;
1258 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1259 break;
1260
1261 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1262 if (unlikely(err))
1263 break;
1264 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1265 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1266 return 0;
1267 case NILFS_ST_DONE:
1268 return 0;
1269 default:
1270 BUG();
1271 }
1272
1273 break_or_fail:
1274 return err;
1275}
1276
1277/**
1278 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1279 * @sci: nilfs_sc_info
1280 * @nilfs: nilfs object
1281 */
1282static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1283 struct the_nilfs *nilfs)
1284{
1285 struct nilfs_segment_buffer *segbuf, *prev;
1286 __u64 nextnum;
1287 int err, alloc = 0;
1288
1289 segbuf = nilfs_segbuf_new(sci->sc_super);
1290 if (unlikely(!segbuf))
1291 return -ENOMEM;
1292
1293 if (list_empty(&sci->sc_write_logs)) {
1294 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1295 nilfs->ns_pseg_offset, nilfs);
1296 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1297 nilfs_shift_to_next_segment(nilfs);
1298 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1299 }
1300
1301 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1302 nextnum = nilfs->ns_nextnum;
1303
1304 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1305 /* Start from the head of a new full segment */
1306 alloc++;
1307 } else {
1308 /* Continue logs */
1309 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1310 nilfs_segbuf_map_cont(segbuf, prev);
1311 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1312 nextnum = prev->sb_nextnum;
1313
1314 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1315 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1316 segbuf->sb_sum.seg_seq++;
1317 alloc++;
1318 }
1319 }
1320
1321 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1322 if (err)
1323 goto failed;
1324
1325 if (alloc) {
1326 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1327 if (err)
1328 goto failed;
1329 }
1330 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1331
1332 BUG_ON(!list_empty(&sci->sc_segbufs));
1333 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1334 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1335 return 0;
1336
1337 failed:
1338 nilfs_segbuf_free(segbuf);
1339 return err;
1340}
1341
1342static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1343 struct the_nilfs *nilfs, int nadd)
1344{
1345 struct nilfs_segment_buffer *segbuf, *prev;
1346 struct inode *sufile = nilfs->ns_sufile;
1347 __u64 nextnextnum;
1348 LIST_HEAD(list);
1349 int err, ret, i;
1350
1351 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1352 /*
1353 * Since the segment specified with nextnum might be allocated during
1354 * the previous construction, the buffer including its segusage may
1355 * not be dirty. The following call ensures that the buffer is dirty
1356 * and will pin the buffer on memory until the sufile is written.
1357 */
1358 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1359 if (unlikely(err))
1360 return err;
1361
1362 for (i = 0; i < nadd; i++) {
1363 /* extend segment info */
1364 err = -ENOMEM;
1365 segbuf = nilfs_segbuf_new(sci->sc_super);
1366 if (unlikely(!segbuf))
1367 goto failed;
1368
1369 /* map this buffer to region of segment on-disk */
1370 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1371 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1372
1373 /* allocate the next next full segment */
1374 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1375 if (unlikely(err))
1376 goto failed_segbuf;
1377
1378 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1379 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1380
1381 list_add_tail(&segbuf->sb_list, &list);
1382 prev = segbuf;
1383 }
1384 list_splice_tail(&list, &sci->sc_segbufs);
1385 return 0;
1386
1387 failed_segbuf:
1388 nilfs_segbuf_free(segbuf);
1389 failed:
1390 list_for_each_entry(segbuf, &list, sb_list) {
1391 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1392 WARN_ON(ret); /* never fails */
1393 }
1394 nilfs_destroy_logs(&list);
1395 return err;
1396}
1397
1398static void nilfs_free_incomplete_logs(struct list_head *logs,
1399 struct the_nilfs *nilfs)
1400{
1401 struct nilfs_segment_buffer *segbuf, *prev;
1402 struct inode *sufile = nilfs->ns_sufile;
1403 int ret;
1404
1405 segbuf = NILFS_FIRST_SEGBUF(logs);
1406 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1407 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1408 WARN_ON(ret); /* never fails */
1409 }
1410 if (atomic_read(&segbuf->sb_err)) {
1411 /* Case 1: The first segment failed */
1412 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1413 /*
1414 * Case 1a: Partial segment appended into an existing
1415 * segment
1416 */
1417 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1418 segbuf->sb_fseg_end);
1419 else /* Case 1b: New full segment */
1420 set_nilfs_discontinued(nilfs);
1421 }
1422
1423 prev = segbuf;
1424 list_for_each_entry_continue(segbuf, logs, sb_list) {
1425 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1426 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1427 WARN_ON(ret); /* never fails */
1428 }
1429 if (atomic_read(&segbuf->sb_err) &&
1430 segbuf->sb_segnum != nilfs->ns_nextnum)
1431 /* Case 2: extended segment (!= next) failed */
1432 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1433 prev = segbuf;
1434 }
1435}
1436
1437static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1438 struct inode *sufile)
1439{
1440 struct nilfs_segment_buffer *segbuf;
1441 unsigned long live_blocks;
1442 int ret;
1443
1444 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1445 live_blocks = segbuf->sb_sum.nblocks +
1446 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1447 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1448 live_blocks,
1449 sci->sc_seg_ctime);
1450 WARN_ON(ret); /* always succeed because the segusage is dirty */
1451 }
1452}
1453
1454static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1455{
1456 struct nilfs_segment_buffer *segbuf;
1457 int ret;
1458
1459 segbuf = NILFS_FIRST_SEGBUF(logs);
1460 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1461 segbuf->sb_pseg_start -
1462 segbuf->sb_fseg_start, 0);
1463 WARN_ON(ret); /* always succeed because the segusage is dirty */
1464
1465 list_for_each_entry_continue(segbuf, logs, sb_list) {
1466 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1467 0, 0);
1468 WARN_ON(ret); /* always succeed */
1469 }
1470}
1471
1472static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1473 struct nilfs_segment_buffer *last,
1474 struct inode *sufile)
1475{
1476 struct nilfs_segment_buffer *segbuf = last;
1477 int ret;
1478
1479 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1480 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1481 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1482 WARN_ON(ret);
1483 }
1484 nilfs_truncate_logs(&sci->sc_segbufs, last);
1485}
1486
1487
1488static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1489 struct the_nilfs *nilfs, int mode)
1490{
1491 struct nilfs_cstage prev_stage = sci->sc_stage;
1492 int err, nadd = 1;
1493
1494 /* Collection retry loop */
1495 for (;;) {
1496 sci->sc_nblk_this_inc = 0;
1497 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1498
1499 err = nilfs_segctor_reset_segment_buffer(sci);
1500 if (unlikely(err))
1501 goto failed;
1502
1503 err = nilfs_segctor_collect_blocks(sci, mode);
1504 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1505 if (!err)
1506 break;
1507
1508 if (unlikely(err != -E2BIG))
1509 goto failed;
1510
1511 /* The current segment is filled up */
1512 if (mode != SC_LSEG_SR ||
1513 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1514 break;
1515
1516 nilfs_clear_logs(&sci->sc_segbufs);
1517
1518 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1519 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1520 sci->sc_freesegs,
1521 sci->sc_nfreesegs,
1522 NULL);
1523 WARN_ON(err); /* do not happen */
1524 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1525 }
1526
1527 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1528 if (unlikely(err))
1529 return err;
1530
1531 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1532 sci->sc_stage = prev_stage;
1533 }
1534 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1535 return 0;
1536
1537 failed:
1538 return err;
1539}
1540
1541static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1542 struct buffer_head *new_bh)
1543{
1544 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1545
1546 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1547 /* The caller must release old_bh */
1548}
1549
1550static int
1551nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1552 struct nilfs_segment_buffer *segbuf,
1553 int mode)
1554{
1555 struct inode *inode = NULL;
1556 sector_t blocknr;
1557 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1558 unsigned long nblocks = 0, ndatablk = 0;
1559 const struct nilfs_sc_operations *sc_op = NULL;
1560 struct nilfs_segsum_pointer ssp;
1561 struct nilfs_finfo *finfo = NULL;
1562 union nilfs_binfo binfo;
1563 struct buffer_head *bh, *bh_org;
1564 ino_t ino = 0;
1565 int err = 0;
1566
1567 if (!nfinfo)
1568 goto out;
1569
1570 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1571 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1572 ssp.offset = sizeof(struct nilfs_segment_summary);
1573
1574 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1575 if (bh == segbuf->sb_super_root)
1576 break;
1577 if (!finfo) {
1578 finfo = nilfs_segctor_map_segsum_entry(
1579 sci, &ssp, sizeof(*finfo));
1580 ino = le64_to_cpu(finfo->fi_ino);
1581 nblocks = le32_to_cpu(finfo->fi_nblocks);
1582 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1583
1584 inode = bh->b_page->mapping->host;
1585
1586 if (mode == SC_LSEG_DSYNC)
1587 sc_op = &nilfs_sc_dsync_ops;
1588 else if (ino == NILFS_DAT_INO)
1589 sc_op = &nilfs_sc_dat_ops;
1590 else /* file blocks */
1591 sc_op = &nilfs_sc_file_ops;
1592 }
1593 bh_org = bh;
1594 get_bh(bh_org);
1595 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1596 &binfo);
1597 if (bh != bh_org)
1598 nilfs_list_replace_buffer(bh_org, bh);
1599 brelse(bh_org);
1600 if (unlikely(err))
1601 goto failed_bmap;
1602
1603 if (ndatablk > 0)
1604 sc_op->write_data_binfo(sci, &ssp, &binfo);
1605 else
1606 sc_op->write_node_binfo(sci, &ssp, &binfo);
1607
1608 blocknr++;
1609 if (--nblocks == 0) {
1610 finfo = NULL;
1611 if (--nfinfo == 0)
1612 break;
1613 } else if (ndatablk > 0)
1614 ndatablk--;
1615 }
1616 out:
1617 return 0;
1618
1619 failed_bmap:
1620 return err;
1621}
1622
1623static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1624{
1625 struct nilfs_segment_buffer *segbuf;
1626 int err;
1627
1628 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1629 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1630 if (unlikely(err))
1631 return err;
1632 nilfs_segbuf_fill_in_segsum(segbuf);
1633 }
1634 return 0;
1635}
1636
1637static void nilfs_begin_page_io(struct page *page)
1638{
1639 if (!page || PageWriteback(page))
1640 /*
1641 * For split b-tree node pages, this function may be called
1642 * twice. We ignore the 2nd or later calls by this check.
1643 */
1644 return;
1645
1646 lock_page(page);
1647 clear_page_dirty_for_io(page);
1648 set_page_writeback(page);
1649 unlock_page(page);
1650}
1651
1652static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1653{
1654 struct nilfs_segment_buffer *segbuf;
1655 struct page *bd_page = NULL, *fs_page = NULL;
1656
1657 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1658 struct buffer_head *bh;
1659
1660 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1661 b_assoc_buffers) {
1662 if (bh->b_page != bd_page) {
1663 if (bd_page) {
1664 lock_page(bd_page);
1665 clear_page_dirty_for_io(bd_page);
1666 set_page_writeback(bd_page);
1667 unlock_page(bd_page);
1668 }
1669 bd_page = bh->b_page;
1670 }
1671 }
1672
1673 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1674 b_assoc_buffers) {
1675 set_buffer_async_write(bh);
1676 if (bh == segbuf->sb_super_root) {
1677 if (bh->b_page != bd_page) {
1678 lock_page(bd_page);
1679 clear_page_dirty_for_io(bd_page);
1680 set_page_writeback(bd_page);
1681 unlock_page(bd_page);
1682 bd_page = bh->b_page;
1683 }
1684 break;
1685 }
1686 if (bh->b_page != fs_page) {
1687 nilfs_begin_page_io(fs_page);
1688 fs_page = bh->b_page;
1689 }
1690 }
1691 }
1692 if (bd_page) {
1693 lock_page(bd_page);
1694 clear_page_dirty_for_io(bd_page);
1695 set_page_writeback(bd_page);
1696 unlock_page(bd_page);
1697 }
1698 nilfs_begin_page_io(fs_page);
1699}
1700
1701static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1702 struct the_nilfs *nilfs)
1703{
1704 int ret;
1705
1706 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1707 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1708 return ret;
1709}
1710
1711static void nilfs_end_page_io(struct page *page, int err)
1712{
1713 if (!page)
1714 return;
1715
1716 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1717 /*
1718 * For b-tree node pages, this function may be called twice
1719 * or more because they might be split in a segment.
1720 */
1721 if (PageDirty(page)) {
1722 /*
1723 * For pages holding split b-tree node buffers, dirty
1724 * flag on the buffers may be cleared discretely.
1725 * In that case, the page is once redirtied for
1726 * remaining buffers, and it must be cancelled if
1727 * all the buffers get cleaned later.
1728 */
1729 lock_page(page);
1730 if (nilfs_page_buffers_clean(page))
1731 __nilfs_clear_page_dirty(page);
1732 unlock_page(page);
1733 }
1734 return;
1735 }
1736
1737 if (!err) {
1738 if (!nilfs_page_buffers_clean(page))
1739 __set_page_dirty_nobuffers(page);
1740 ClearPageError(page);
1741 } else {
1742 __set_page_dirty_nobuffers(page);
1743 SetPageError(page);
1744 }
1745
1746 end_page_writeback(page);
1747}
1748
1749static void nilfs_abort_logs(struct list_head *logs, int err)
1750{
1751 struct nilfs_segment_buffer *segbuf;
1752 struct page *bd_page = NULL, *fs_page = NULL;
1753 struct buffer_head *bh;
1754
1755 if (list_empty(logs))
1756 return;
1757
1758 list_for_each_entry(segbuf, logs, sb_list) {
1759 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1760 b_assoc_buffers) {
1761 if (bh->b_page != bd_page) {
1762 if (bd_page)
1763 end_page_writeback(bd_page);
1764 bd_page = bh->b_page;
1765 }
1766 }
1767
1768 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1769 b_assoc_buffers) {
1770 clear_buffer_async_write(bh);
1771 if (bh == segbuf->sb_super_root) {
1772 if (bh->b_page != bd_page) {
1773 end_page_writeback(bd_page);
1774 bd_page = bh->b_page;
1775 }
1776 break;
1777 }
1778 if (bh->b_page != fs_page) {
1779 nilfs_end_page_io(fs_page, err);
1780 fs_page = bh->b_page;
1781 }
1782 }
1783 }
1784 if (bd_page)
1785 end_page_writeback(bd_page);
1786
1787 nilfs_end_page_io(fs_page, err);
1788}
1789
1790static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1791 struct the_nilfs *nilfs, int err)
1792{
1793 LIST_HEAD(logs);
1794 int ret;
1795
1796 list_splice_tail_init(&sci->sc_write_logs, &logs);
1797 ret = nilfs_wait_on_logs(&logs);
1798 nilfs_abort_logs(&logs, ret ? : err);
1799
1800 list_splice_tail_init(&sci->sc_segbufs, &logs);
1801 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1802 nilfs_free_incomplete_logs(&logs, nilfs);
1803
1804 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1805 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1806 sci->sc_freesegs,
1807 sci->sc_nfreesegs,
1808 NULL);
1809 WARN_ON(ret); /* do not happen */
1810 }
1811
1812 nilfs_destroy_logs(&logs);
1813}
1814
1815static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1816 struct nilfs_segment_buffer *segbuf)
1817{
1818 nilfs->ns_segnum = segbuf->sb_segnum;
1819 nilfs->ns_nextnum = segbuf->sb_nextnum;
1820 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1821 + segbuf->sb_sum.nblocks;
1822 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1823 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1824}
1825
1826static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1827{
1828 struct nilfs_segment_buffer *segbuf;
1829 struct page *bd_page = NULL, *fs_page = NULL;
1830 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1831 int update_sr = false;
1832
1833 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1834 struct buffer_head *bh;
1835
1836 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1837 b_assoc_buffers) {
1838 set_buffer_uptodate(bh);
1839 clear_buffer_dirty(bh);
1840 if (bh->b_page != bd_page) {
1841 if (bd_page)
1842 end_page_writeback(bd_page);
1843 bd_page = bh->b_page;
1844 }
1845 }
1846 /*
1847 * We assume that the buffers which belong to the same page
1848 * continue over the buffer list.
1849 * Under this assumption, the last BHs of pages is
1850 * identifiable by the discontinuity of bh->b_page
1851 * (page != fs_page).
1852 *
1853 * For B-tree node blocks, however, this assumption is not
1854 * guaranteed. The cleanup code of B-tree node pages needs
1855 * special care.
1856 */
1857 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1858 b_assoc_buffers) {
1859 const unsigned long set_bits = BIT(BH_Uptodate);
1860 const unsigned long clear_bits =
1861 (BIT(BH_Dirty) | BIT(BH_Async_Write) |
1862 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) |
1863 BIT(BH_NILFS_Redirected));
1864
1865 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1866 if (bh == segbuf->sb_super_root) {
1867 if (bh->b_page != bd_page) {
1868 end_page_writeback(bd_page);
1869 bd_page = bh->b_page;
1870 }
1871 update_sr = true;
1872 break;
1873 }
1874 if (bh->b_page != fs_page) {
1875 nilfs_end_page_io(fs_page, 0);
1876 fs_page = bh->b_page;
1877 }
1878 }
1879
1880 if (!nilfs_segbuf_simplex(segbuf)) {
1881 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1882 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1883 sci->sc_lseg_stime = jiffies;
1884 }
1885 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1886 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1887 }
1888 }
1889 /*
1890 * Since pages may continue over multiple segment buffers,
1891 * end of the last page must be checked outside of the loop.
1892 */
1893 if (bd_page)
1894 end_page_writeback(bd_page);
1895
1896 nilfs_end_page_io(fs_page, 0);
1897
1898 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1899
1900 if (nilfs_doing_gc())
1901 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1902 else
1903 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1904
1905 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1906
1907 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1908 nilfs_set_next_segment(nilfs, segbuf);
1909
1910 if (update_sr) {
1911 nilfs->ns_flushed_device = 0;
1912 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1913 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1914
1915 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1916 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1917 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1918 nilfs_segctor_clear_metadata_dirty(sci);
1919 } else
1920 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1921}
1922
1923static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1924{
1925 int ret;
1926
1927 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1928 if (!ret) {
1929 nilfs_segctor_complete_write(sci);
1930 nilfs_destroy_logs(&sci->sc_write_logs);
1931 }
1932 return ret;
1933}
1934
1935static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1936 struct the_nilfs *nilfs)
1937{
1938 struct nilfs_inode_info *ii, *n;
1939 struct inode *ifile = sci->sc_root->ifile;
1940
1941 spin_lock(&nilfs->ns_inode_lock);
1942 retry:
1943 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1944 if (!ii->i_bh) {
1945 struct buffer_head *ibh;
1946 int err;
1947
1948 spin_unlock(&nilfs->ns_inode_lock);
1949 err = nilfs_ifile_get_inode_block(
1950 ifile, ii->vfs_inode.i_ino, &ibh);
1951 if (unlikely(err)) {
1952 nilfs_msg(sci->sc_super, KERN_WARNING,
1953 "log writer: error %d getting inode block (ino=%lu)",
1954 err, ii->vfs_inode.i_ino);
1955 return err;
1956 }
1957 spin_lock(&nilfs->ns_inode_lock);
1958 if (likely(!ii->i_bh))
1959 ii->i_bh = ibh;
1960 else
1961 brelse(ibh);
1962 goto retry;
1963 }
1964
1965 // Always redirty the buffer to avoid race condition
1966 mark_buffer_dirty(ii->i_bh);
1967 nilfs_mdt_mark_dirty(ifile);
1968
1969 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1970 set_bit(NILFS_I_BUSY, &ii->i_state);
1971 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1972 }
1973 spin_unlock(&nilfs->ns_inode_lock);
1974
1975 return 0;
1976}
1977
1978static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1979 struct the_nilfs *nilfs)
1980{
1981 struct nilfs_inode_info *ii, *n;
1982 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
1983 int defer_iput = false;
1984
1985 spin_lock(&nilfs->ns_inode_lock);
1986 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1987 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1988 test_bit(NILFS_I_DIRTY, &ii->i_state))
1989 continue;
1990
1991 clear_bit(NILFS_I_BUSY, &ii->i_state);
1992 brelse(ii->i_bh);
1993 ii->i_bh = NULL;
1994 list_del_init(&ii->i_dirty);
1995 if (!ii->vfs_inode.i_nlink || during_mount) {
1996 /*
1997 * Defer calling iput() to avoid deadlocks if
1998 * i_nlink == 0 or mount is not yet finished.
1999 */
2000 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
2001 defer_iput = true;
2002 } else {
2003 spin_unlock(&nilfs->ns_inode_lock);
2004 iput(&ii->vfs_inode);
2005 spin_lock(&nilfs->ns_inode_lock);
2006 }
2007 }
2008 spin_unlock(&nilfs->ns_inode_lock);
2009
2010 if (defer_iput)
2011 schedule_work(&sci->sc_iput_work);
2012}
2013
2014/*
2015 * Main procedure of segment constructor
2016 */
2017static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2018{
2019 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2020 int err;
2021
2022 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2023 sci->sc_cno = nilfs->ns_cno;
2024
2025 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2026 if (unlikely(err))
2027 goto out;
2028
2029 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2030 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2031
2032 if (nilfs_segctor_clean(sci))
2033 goto out;
2034
2035 do {
2036 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2037
2038 err = nilfs_segctor_begin_construction(sci, nilfs);
2039 if (unlikely(err))
2040 goto out;
2041
2042 /* Update time stamp */
2043 sci->sc_seg_ctime = ktime_get_real_seconds();
2044
2045 err = nilfs_segctor_collect(sci, nilfs, mode);
2046 if (unlikely(err))
2047 goto failed;
2048
2049 /* Avoid empty segment */
2050 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2051 nilfs_segbuf_empty(sci->sc_curseg)) {
2052 nilfs_segctor_abort_construction(sci, nilfs, 1);
2053 goto out;
2054 }
2055
2056 err = nilfs_segctor_assign(sci, mode);
2057 if (unlikely(err))
2058 goto failed;
2059
2060 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2061 nilfs_segctor_fill_in_file_bmap(sci);
2062
2063 if (mode == SC_LSEG_SR &&
2064 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2065 err = nilfs_segctor_fill_in_checkpoint(sci);
2066 if (unlikely(err))
2067 goto failed_to_write;
2068
2069 nilfs_segctor_fill_in_super_root(sci, nilfs);
2070 }
2071 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2072
2073 /* Write partial segments */
2074 nilfs_segctor_prepare_write(sci);
2075
2076 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2077 nilfs->ns_crc_seed);
2078
2079 err = nilfs_segctor_write(sci, nilfs);
2080 if (unlikely(err))
2081 goto failed_to_write;
2082
2083 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2084 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2085 /*
2086 * At this point, we avoid double buffering
2087 * for blocksize < pagesize because page dirty
2088 * flag is turned off during write and dirty
2089 * buffers are not properly collected for
2090 * pages crossing over segments.
2091 */
2092 err = nilfs_segctor_wait(sci);
2093 if (err)
2094 goto failed_to_write;
2095 }
2096 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2097
2098 out:
2099 nilfs_segctor_drop_written_files(sci, nilfs);
2100 return err;
2101
2102 failed_to_write:
2103 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2104 nilfs_redirty_inodes(&sci->sc_dirty_files);
2105
2106 failed:
2107 if (nilfs_doing_gc())
2108 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2109 nilfs_segctor_abort_construction(sci, nilfs, err);
2110 goto out;
2111}
2112
2113/**
2114 * nilfs_segctor_start_timer - set timer of background write
2115 * @sci: nilfs_sc_info
2116 *
2117 * If the timer has already been set, it ignores the new request.
2118 * This function MUST be called within a section locking the segment
2119 * semaphore.
2120 */
2121static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2122{
2123 spin_lock(&sci->sc_state_lock);
2124 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2125 sci->sc_timer.expires = jiffies + sci->sc_interval;
2126 add_timer(&sci->sc_timer);
2127 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2128 }
2129 spin_unlock(&sci->sc_state_lock);
2130}
2131
2132static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2133{
2134 spin_lock(&sci->sc_state_lock);
2135 if (!(sci->sc_flush_request & BIT(bn))) {
2136 unsigned long prev_req = sci->sc_flush_request;
2137
2138 sci->sc_flush_request |= BIT(bn);
2139 if (!prev_req)
2140 wake_up(&sci->sc_wait_daemon);
2141 }
2142 spin_unlock(&sci->sc_state_lock);
2143}
2144
2145/**
2146 * nilfs_flush_segment - trigger a segment construction for resource control
2147 * @sb: super block
2148 * @ino: inode number of the file to be flushed out.
2149 */
2150void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2151{
2152 struct the_nilfs *nilfs = sb->s_fs_info;
2153 struct nilfs_sc_info *sci = nilfs->ns_writer;
2154
2155 if (!sci || nilfs_doing_construction())
2156 return;
2157 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2158 /* assign bit 0 to data files */
2159}
2160
2161struct nilfs_segctor_wait_request {
2162 wait_queue_entry_t wq;
2163 __u32 seq;
2164 int err;
2165 atomic_t done;
2166};
2167
2168static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2169{
2170 struct nilfs_segctor_wait_request wait_req;
2171 int err = 0;
2172
2173 spin_lock(&sci->sc_state_lock);
2174 init_wait(&wait_req.wq);
2175 wait_req.err = 0;
2176 atomic_set(&wait_req.done, 0);
2177 wait_req.seq = ++sci->sc_seq_request;
2178 spin_unlock(&sci->sc_state_lock);
2179
2180 init_waitqueue_entry(&wait_req.wq, current);
2181 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2182 set_current_state(TASK_INTERRUPTIBLE);
2183 wake_up(&sci->sc_wait_daemon);
2184
2185 for (;;) {
2186 if (atomic_read(&wait_req.done)) {
2187 err = wait_req.err;
2188 break;
2189 }
2190 if (!signal_pending(current)) {
2191 schedule();
2192 continue;
2193 }
2194 err = -ERESTARTSYS;
2195 break;
2196 }
2197 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2198 return err;
2199}
2200
2201static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2202{
2203 struct nilfs_segctor_wait_request *wrq, *n;
2204 unsigned long flags;
2205
2206 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2207 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
2208 if (!atomic_read(&wrq->done) &&
2209 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2210 wrq->err = err;
2211 atomic_set(&wrq->done, 1);
2212 }
2213 if (atomic_read(&wrq->done)) {
2214 wrq->wq.func(&wrq->wq,
2215 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2216 0, NULL);
2217 }
2218 }
2219 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2220}
2221
2222/**
2223 * nilfs_construct_segment - construct a logical segment
2224 * @sb: super block
2225 *
2226 * Return Value: On success, 0 is retured. On errors, one of the following
2227 * negative error code is returned.
2228 *
2229 * %-EROFS - Read only filesystem.
2230 *
2231 * %-EIO - I/O error
2232 *
2233 * %-ENOSPC - No space left on device (only in a panic state).
2234 *
2235 * %-ERESTARTSYS - Interrupted.
2236 *
2237 * %-ENOMEM - Insufficient memory available.
2238 */
2239int nilfs_construct_segment(struct super_block *sb)
2240{
2241 struct the_nilfs *nilfs = sb->s_fs_info;
2242 struct nilfs_sc_info *sci = nilfs->ns_writer;
2243 struct nilfs_transaction_info *ti;
2244 int err;
2245
2246 if (!sci)
2247 return -EROFS;
2248
2249 /* A call inside transactions causes a deadlock. */
2250 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2251
2252 err = nilfs_segctor_sync(sci);
2253 return err;
2254}
2255
2256/**
2257 * nilfs_construct_dsync_segment - construct a data-only logical segment
2258 * @sb: super block
2259 * @inode: inode whose data blocks should be written out
2260 * @start: start byte offset
2261 * @end: end byte offset (inclusive)
2262 *
2263 * Return Value: On success, 0 is retured. On errors, one of the following
2264 * negative error code is returned.
2265 *
2266 * %-EROFS - Read only filesystem.
2267 *
2268 * %-EIO - I/O error
2269 *
2270 * %-ENOSPC - No space left on device (only in a panic state).
2271 *
2272 * %-ERESTARTSYS - Interrupted.
2273 *
2274 * %-ENOMEM - Insufficient memory available.
2275 */
2276int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2277 loff_t start, loff_t end)
2278{
2279 struct the_nilfs *nilfs = sb->s_fs_info;
2280 struct nilfs_sc_info *sci = nilfs->ns_writer;
2281 struct nilfs_inode_info *ii;
2282 struct nilfs_transaction_info ti;
2283 int err = 0;
2284
2285 if (!sci)
2286 return -EROFS;
2287
2288 nilfs_transaction_lock(sb, &ti, 0);
2289
2290 ii = NILFS_I(inode);
2291 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2292 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2293 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2294 nilfs_discontinued(nilfs)) {
2295 nilfs_transaction_unlock(sb);
2296 err = nilfs_segctor_sync(sci);
2297 return err;
2298 }
2299
2300 spin_lock(&nilfs->ns_inode_lock);
2301 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2302 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2303 spin_unlock(&nilfs->ns_inode_lock);
2304 nilfs_transaction_unlock(sb);
2305 return 0;
2306 }
2307 spin_unlock(&nilfs->ns_inode_lock);
2308 sci->sc_dsync_inode = ii;
2309 sci->sc_dsync_start = start;
2310 sci->sc_dsync_end = end;
2311
2312 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2313 if (!err)
2314 nilfs->ns_flushed_device = 0;
2315
2316 nilfs_transaction_unlock(sb);
2317 return err;
2318}
2319
2320#define FLUSH_FILE_BIT (0x1) /* data file only */
2321#define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2322
2323/**
2324 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2325 * @sci: segment constructor object
2326 */
2327static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2328{
2329 spin_lock(&sci->sc_state_lock);
2330 sci->sc_seq_accepted = sci->sc_seq_request;
2331 spin_unlock(&sci->sc_state_lock);
2332 del_timer_sync(&sci->sc_timer);
2333}
2334
2335/**
2336 * nilfs_segctor_notify - notify the result of request to caller threads
2337 * @sci: segment constructor object
2338 * @mode: mode of log forming
2339 * @err: error code to be notified
2340 */
2341static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2342{
2343 /* Clear requests (even when the construction failed) */
2344 spin_lock(&sci->sc_state_lock);
2345
2346 if (mode == SC_LSEG_SR) {
2347 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2348 sci->sc_seq_done = sci->sc_seq_accepted;
2349 nilfs_segctor_wakeup(sci, err);
2350 sci->sc_flush_request = 0;
2351 } else {
2352 if (mode == SC_FLUSH_FILE)
2353 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2354 else if (mode == SC_FLUSH_DAT)
2355 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2356
2357 /* re-enable timer if checkpoint creation was not done */
2358 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2359 time_before(jiffies, sci->sc_timer.expires))
2360 add_timer(&sci->sc_timer);
2361 }
2362 spin_unlock(&sci->sc_state_lock);
2363}
2364
2365/**
2366 * nilfs_segctor_construct - form logs and write them to disk
2367 * @sci: segment constructor object
2368 * @mode: mode of log forming
2369 */
2370static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2371{
2372 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2373 struct nilfs_super_block **sbp;
2374 int err = 0;
2375
2376 nilfs_segctor_accept(sci);
2377
2378 if (nilfs_discontinued(nilfs))
2379 mode = SC_LSEG_SR;
2380 if (!nilfs_segctor_confirm(sci))
2381 err = nilfs_segctor_do_construct(sci, mode);
2382
2383 if (likely(!err)) {
2384 if (mode != SC_FLUSH_DAT)
2385 atomic_set(&nilfs->ns_ndirtyblks, 0);
2386 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2387 nilfs_discontinued(nilfs)) {
2388 down_write(&nilfs->ns_sem);
2389 err = -EIO;
2390 sbp = nilfs_prepare_super(sci->sc_super,
2391 nilfs_sb_will_flip(nilfs));
2392 if (likely(sbp)) {
2393 nilfs_set_log_cursor(sbp[0], nilfs);
2394 err = nilfs_commit_super(sci->sc_super,
2395 NILFS_SB_COMMIT);
2396 }
2397 up_write(&nilfs->ns_sem);
2398 }
2399 }
2400
2401 nilfs_segctor_notify(sci, mode, err);
2402 return err;
2403}
2404
2405static void nilfs_construction_timeout(struct timer_list *t)
2406{
2407 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2408
2409 wake_up_process(sci->sc_timer_task);
2410}
2411
2412static void
2413nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2414{
2415 struct nilfs_inode_info *ii, *n;
2416
2417 list_for_each_entry_safe(ii, n, head, i_dirty) {
2418 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2419 continue;
2420 list_del_init(&ii->i_dirty);
2421 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2422 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2423 iput(&ii->vfs_inode);
2424 }
2425}
2426
2427int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2428 void **kbufs)
2429{
2430 struct the_nilfs *nilfs = sb->s_fs_info;
2431 struct nilfs_sc_info *sci = nilfs->ns_writer;
2432 struct nilfs_transaction_info ti;
2433 int err;
2434
2435 if (unlikely(!sci))
2436 return -EROFS;
2437
2438 nilfs_transaction_lock(sb, &ti, 1);
2439
2440 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2441 if (unlikely(err))
2442 goto out_unlock;
2443
2444 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2445 if (unlikely(err)) {
2446 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2447 goto out_unlock;
2448 }
2449
2450 sci->sc_freesegs = kbufs[4];
2451 sci->sc_nfreesegs = argv[4].v_nmembs;
2452 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2453
2454 for (;;) {
2455 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2456 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2457
2458 if (likely(!err))
2459 break;
2460
2461 nilfs_msg(sb, KERN_WARNING, "error %d cleaning segments", err);
2462 set_current_state(TASK_INTERRUPTIBLE);
2463 schedule_timeout(sci->sc_interval);
2464 }
2465 if (nilfs_test_opt(nilfs, DISCARD)) {
2466 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2467 sci->sc_nfreesegs);
2468 if (ret) {
2469 nilfs_msg(sb, KERN_WARNING,
2470 "error %d on discard request, turning discards off for the device",
2471 ret);
2472 nilfs_clear_opt(nilfs, DISCARD);
2473 }
2474 }
2475
2476 out_unlock:
2477 sci->sc_freesegs = NULL;
2478 sci->sc_nfreesegs = 0;
2479 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2480 nilfs_transaction_unlock(sb);
2481 return err;
2482}
2483
2484static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2485{
2486 struct nilfs_transaction_info ti;
2487
2488 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2489 nilfs_segctor_construct(sci, mode);
2490
2491 /*
2492 * Unclosed segment should be retried. We do this using sc_timer.
2493 * Timeout of sc_timer will invoke complete construction which leads
2494 * to close the current logical segment.
2495 */
2496 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2497 nilfs_segctor_start_timer(sci);
2498
2499 nilfs_transaction_unlock(sci->sc_super);
2500}
2501
2502static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2503{
2504 int mode = 0;
2505
2506 spin_lock(&sci->sc_state_lock);
2507 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2508 SC_FLUSH_DAT : SC_FLUSH_FILE;
2509 spin_unlock(&sci->sc_state_lock);
2510
2511 if (mode) {
2512 nilfs_segctor_do_construct(sci, mode);
2513
2514 spin_lock(&sci->sc_state_lock);
2515 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2516 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2517 spin_unlock(&sci->sc_state_lock);
2518 }
2519 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2520}
2521
2522static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2523{
2524 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2525 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2526 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2527 return SC_FLUSH_FILE;
2528 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2529 return SC_FLUSH_DAT;
2530 }
2531 return SC_LSEG_SR;
2532}
2533
2534/**
2535 * nilfs_segctor_thread - main loop of the segment constructor thread.
2536 * @arg: pointer to a struct nilfs_sc_info.
2537 *
2538 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2539 * to execute segment constructions.
2540 */
2541static int nilfs_segctor_thread(void *arg)
2542{
2543 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2544 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2545 int timeout = 0;
2546
2547 sci->sc_timer_task = current;
2548
2549 /* start sync. */
2550 sci->sc_task = current;
2551 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2552 nilfs_msg(sci->sc_super, KERN_INFO,
2553 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
2554 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2555
2556 spin_lock(&sci->sc_state_lock);
2557 loop:
2558 for (;;) {
2559 int mode;
2560
2561 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2562 goto end_thread;
2563
2564 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2565 mode = SC_LSEG_SR;
2566 else if (sci->sc_flush_request)
2567 mode = nilfs_segctor_flush_mode(sci);
2568 else
2569 break;
2570
2571 spin_unlock(&sci->sc_state_lock);
2572 nilfs_segctor_thread_construct(sci, mode);
2573 spin_lock(&sci->sc_state_lock);
2574 timeout = 0;
2575 }
2576
2577
2578 if (freezing(current)) {
2579 spin_unlock(&sci->sc_state_lock);
2580 try_to_freeze();
2581 spin_lock(&sci->sc_state_lock);
2582 } else {
2583 DEFINE_WAIT(wait);
2584 int should_sleep = 1;
2585
2586 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2587 TASK_INTERRUPTIBLE);
2588
2589 if (sci->sc_seq_request != sci->sc_seq_done)
2590 should_sleep = 0;
2591 else if (sci->sc_flush_request)
2592 should_sleep = 0;
2593 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2594 should_sleep = time_before(jiffies,
2595 sci->sc_timer.expires);
2596
2597 if (should_sleep) {
2598 spin_unlock(&sci->sc_state_lock);
2599 schedule();
2600 spin_lock(&sci->sc_state_lock);
2601 }
2602 finish_wait(&sci->sc_wait_daemon, &wait);
2603 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2604 time_after_eq(jiffies, sci->sc_timer.expires));
2605
2606 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2607 set_nilfs_discontinued(nilfs);
2608 }
2609 goto loop;
2610
2611 end_thread:
2612 spin_unlock(&sci->sc_state_lock);
2613
2614 /* end sync. */
2615 sci->sc_task = NULL;
2616 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2617 return 0;
2618}
2619
2620static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2621{
2622 struct task_struct *t;
2623
2624 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2625 if (IS_ERR(t)) {
2626 int err = PTR_ERR(t);
2627
2628 nilfs_msg(sci->sc_super, KERN_ERR,
2629 "error %d creating segctord thread", err);
2630 return err;
2631 }
2632 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2633 return 0;
2634}
2635
2636static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2637 __acquires(&sci->sc_state_lock)
2638 __releases(&sci->sc_state_lock)
2639{
2640 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2641
2642 while (sci->sc_task) {
2643 wake_up(&sci->sc_wait_daemon);
2644 spin_unlock(&sci->sc_state_lock);
2645 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2646 spin_lock(&sci->sc_state_lock);
2647 }
2648}
2649
2650/*
2651 * Setup & clean-up functions
2652 */
2653static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2654 struct nilfs_root *root)
2655{
2656 struct the_nilfs *nilfs = sb->s_fs_info;
2657 struct nilfs_sc_info *sci;
2658
2659 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2660 if (!sci)
2661 return NULL;
2662
2663 sci->sc_super = sb;
2664
2665 nilfs_get_root(root);
2666 sci->sc_root = root;
2667
2668 init_waitqueue_head(&sci->sc_wait_request);
2669 init_waitqueue_head(&sci->sc_wait_daemon);
2670 init_waitqueue_head(&sci->sc_wait_task);
2671 spin_lock_init(&sci->sc_state_lock);
2672 INIT_LIST_HEAD(&sci->sc_dirty_files);
2673 INIT_LIST_HEAD(&sci->sc_segbufs);
2674 INIT_LIST_HEAD(&sci->sc_write_logs);
2675 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2676 INIT_LIST_HEAD(&sci->sc_iput_queue);
2677 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2678 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
2679
2680 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2681 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2682 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2683
2684 if (nilfs->ns_interval)
2685 sci->sc_interval = HZ * nilfs->ns_interval;
2686 if (nilfs->ns_watermark)
2687 sci->sc_watermark = nilfs->ns_watermark;
2688 return sci;
2689}
2690
2691static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2692{
2693 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2694
2695 /*
2696 * The segctord thread was stopped and its timer was removed.
2697 * But some tasks remain.
2698 */
2699 do {
2700 struct nilfs_transaction_info ti;
2701
2702 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2703 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2704 nilfs_transaction_unlock(sci->sc_super);
2705
2706 flush_work(&sci->sc_iput_work);
2707
2708 } while (ret && retrycount-- > 0);
2709}
2710
2711/**
2712 * nilfs_segctor_destroy - destroy the segment constructor.
2713 * @sci: nilfs_sc_info
2714 *
2715 * nilfs_segctor_destroy() kills the segctord thread and frees
2716 * the nilfs_sc_info struct.
2717 * Caller must hold the segment semaphore.
2718 */
2719static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2720{
2721 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2722 int flag;
2723
2724 up_write(&nilfs->ns_segctor_sem);
2725
2726 spin_lock(&sci->sc_state_lock);
2727 nilfs_segctor_kill_thread(sci);
2728 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2729 || sci->sc_seq_request != sci->sc_seq_done);
2730 spin_unlock(&sci->sc_state_lock);
2731
2732 if (flush_work(&sci->sc_iput_work))
2733 flag = true;
2734
2735 if (flag || !nilfs_segctor_confirm(sci))
2736 nilfs_segctor_write_out(sci);
2737
2738 if (!list_empty(&sci->sc_dirty_files)) {
2739 nilfs_msg(sci->sc_super, KERN_WARNING,
2740 "disposed unprocessed dirty file(s) when stopping log writer");
2741 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2742 }
2743
2744 if (!list_empty(&sci->sc_iput_queue)) {
2745 nilfs_msg(sci->sc_super, KERN_WARNING,
2746 "disposed unprocessed inode(s) in iput queue when stopping log writer");
2747 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2748 }
2749
2750 WARN_ON(!list_empty(&sci->sc_segbufs));
2751 WARN_ON(!list_empty(&sci->sc_write_logs));
2752
2753 nilfs_put_root(sci->sc_root);
2754
2755 down_write(&nilfs->ns_segctor_sem);
2756
2757 del_timer_sync(&sci->sc_timer);
2758 kfree(sci);
2759}
2760
2761/**
2762 * nilfs_attach_log_writer - attach log writer
2763 * @sb: super block instance
2764 * @root: root object of the current filesystem tree
2765 *
2766 * This allocates a log writer object, initializes it, and starts the
2767 * log writer.
2768 *
2769 * Return Value: On success, 0 is returned. On error, one of the following
2770 * negative error code is returned.
2771 *
2772 * %-ENOMEM - Insufficient memory available.
2773 */
2774int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2775{
2776 struct the_nilfs *nilfs = sb->s_fs_info;
2777 int err;
2778
2779 if (nilfs->ns_writer) {
2780 /*
2781 * This happens if the filesystem was remounted
2782 * read/write after nilfs_error degenerated it into a
2783 * read-only mount.
2784 */
2785 nilfs_detach_log_writer(sb);
2786 }
2787
2788 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2789 if (!nilfs->ns_writer)
2790 return -ENOMEM;
2791
2792 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2793 if (err) {
2794 kfree(nilfs->ns_writer);
2795 nilfs->ns_writer = NULL;
2796 }
2797 return err;
2798}
2799
2800/**
2801 * nilfs_detach_log_writer - destroy log writer
2802 * @sb: super block instance
2803 *
2804 * This kills log writer daemon, frees the log writer object, and
2805 * destroys list of dirty files.
2806 */
2807void nilfs_detach_log_writer(struct super_block *sb)
2808{
2809 struct the_nilfs *nilfs = sb->s_fs_info;
2810 LIST_HEAD(garbage_list);
2811
2812 down_write(&nilfs->ns_segctor_sem);
2813 if (nilfs->ns_writer) {
2814 nilfs_segctor_destroy(nilfs->ns_writer);
2815 nilfs->ns_writer = NULL;
2816 }
2817
2818 /* Force to free the list of dirty files */
2819 spin_lock(&nilfs->ns_inode_lock);
2820 if (!list_empty(&nilfs->ns_dirty_files)) {
2821 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2822 nilfs_msg(sb, KERN_WARNING,
2823 "disposed unprocessed dirty file(s) when detaching log writer");
2824 }
2825 spin_unlock(&nilfs->ns_inode_lock);
2826 up_write(&nilfs->ns_segctor_sem);
2827
2828 nilfs_dispose_list(nilfs, &garbage_list, 1);
2829}