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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// SPDX-License-Identifier: GPL-2.0+
2/*
3 * 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_ge(a, b) \
138 (typecheck(__u32, a) && typecheck(__u32, b) && \
139 ((__s32)(a) - (__s32)(b) >= 0))
140
141static int nilfs_prepare_segment_lock(struct super_block *sb,
142 struct nilfs_transaction_info *ti)
143{
144 struct nilfs_transaction_info *cur_ti = current->journal_info;
145 void *save = NULL;
146
147 if (cur_ti) {
148 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
149 return ++cur_ti->ti_count;
150
151 /*
152 * If journal_info field is occupied by other FS,
153 * it is saved and will be restored on
154 * nilfs_transaction_commit().
155 */
156 nilfs_warn(sb, "journal info from a different FS");
157 save = current->journal_info;
158 }
159 if (!ti) {
160 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
161 if (!ti)
162 return -ENOMEM;
163 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
164 } else {
165 ti->ti_flags = 0;
166 }
167 ti->ti_count = 0;
168 ti->ti_save = save;
169 ti->ti_magic = NILFS_TI_MAGIC;
170 current->journal_info = ti;
171 return 0;
172}
173
174/**
175 * nilfs_transaction_begin - start indivisible file operations.
176 * @sb: super block
177 * @ti: nilfs_transaction_info
178 * @vacancy_check: flags for vacancy rate checks
179 *
180 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
181 * the segment semaphore, to make a segment construction and write tasks
182 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
183 * The region enclosed by these two functions can be nested. To avoid a
184 * deadlock, the semaphore is only acquired or released in the outermost call.
185 *
186 * This function allocates a nilfs_transaction_info struct to keep context
187 * information on it. It is initialized and hooked onto the current task in
188 * the outermost call. If a pre-allocated struct is given to @ti, it is used
189 * instead; otherwise a new struct is assigned from a slab.
190 *
191 * When @vacancy_check flag is set, this function will check the amount of
192 * free space, and will wait for the GC to reclaim disk space if low capacity.
193 *
194 * Return Value: On success, 0 is returned. On error, one of the following
195 * negative error code is returned.
196 *
197 * %-ENOMEM - Insufficient memory available.
198 *
199 * %-ENOSPC - No space left on device
200 */
201int nilfs_transaction_begin(struct super_block *sb,
202 struct nilfs_transaction_info *ti,
203 int vacancy_check)
204{
205 struct the_nilfs *nilfs;
206 int ret = nilfs_prepare_segment_lock(sb, ti);
207 struct nilfs_transaction_info *trace_ti;
208
209 if (unlikely(ret < 0))
210 return ret;
211 if (ret > 0) {
212 trace_ti = current->journal_info;
213
214 trace_nilfs2_transaction_transition(sb, trace_ti,
215 trace_ti->ti_count, trace_ti->ti_flags,
216 TRACE_NILFS2_TRANSACTION_BEGIN);
217 return 0;
218 }
219
220 sb_start_intwrite(sb);
221
222 nilfs = sb->s_fs_info;
223 down_read(&nilfs->ns_segctor_sem);
224 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
225 up_read(&nilfs->ns_segctor_sem);
226 ret = -ENOSPC;
227 goto failed;
228 }
229
230 trace_ti = current->journal_info;
231 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
232 trace_ti->ti_flags,
233 TRACE_NILFS2_TRANSACTION_BEGIN);
234 return 0;
235
236 failed:
237 ti = current->journal_info;
238 current->journal_info = ti->ti_save;
239 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
240 kmem_cache_free(nilfs_transaction_cachep, ti);
241 sb_end_intwrite(sb);
242 return ret;
243}
244
245/**
246 * nilfs_transaction_commit - commit indivisible file operations.
247 * @sb: super block
248 *
249 * nilfs_transaction_commit() releases the read semaphore which is
250 * acquired by nilfs_transaction_begin(). This is only performed
251 * in outermost call of this function. If a commit flag is set,
252 * nilfs_transaction_commit() sets a timer to start the segment
253 * constructor. If a sync flag is set, it starts construction
254 * directly.
255 */
256int nilfs_transaction_commit(struct super_block *sb)
257{
258 struct nilfs_transaction_info *ti = current->journal_info;
259 struct the_nilfs *nilfs = sb->s_fs_info;
260 int err = 0;
261
262 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
263 ti->ti_flags |= NILFS_TI_COMMIT;
264 if (ti->ti_count > 0) {
265 ti->ti_count--;
266 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
267 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
268 return 0;
269 }
270 if (nilfs->ns_writer) {
271 struct nilfs_sc_info *sci = nilfs->ns_writer;
272
273 if (ti->ti_flags & NILFS_TI_COMMIT)
274 nilfs_segctor_start_timer(sci);
275 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
276 nilfs_segctor_do_flush(sci, 0);
277 }
278 up_read(&nilfs->ns_segctor_sem);
279 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
280 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
281
282 current->journal_info = ti->ti_save;
283
284 if (ti->ti_flags & NILFS_TI_SYNC)
285 err = nilfs_construct_segment(sb);
286 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
287 kmem_cache_free(nilfs_transaction_cachep, ti);
288 sb_end_intwrite(sb);
289 return err;
290}
291
292void nilfs_transaction_abort(struct super_block *sb)
293{
294 struct nilfs_transaction_info *ti = current->journal_info;
295 struct the_nilfs *nilfs = sb->s_fs_info;
296
297 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
298 if (ti->ti_count > 0) {
299 ti->ti_count--;
300 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
301 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
302 return;
303 }
304 up_read(&nilfs->ns_segctor_sem);
305
306 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
307 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
308
309 current->journal_info = ti->ti_save;
310 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
311 kmem_cache_free(nilfs_transaction_cachep, ti);
312 sb_end_intwrite(sb);
313}
314
315void nilfs_relax_pressure_in_lock(struct super_block *sb)
316{
317 struct the_nilfs *nilfs = sb->s_fs_info;
318 struct nilfs_sc_info *sci = nilfs->ns_writer;
319
320 if (sb_rdonly(sb) || unlikely(!sci) || !sci->sc_flush_request)
321 return;
322
323 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
324 up_read(&nilfs->ns_segctor_sem);
325
326 down_write(&nilfs->ns_segctor_sem);
327 if (sci->sc_flush_request &&
328 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
329 struct nilfs_transaction_info *ti = current->journal_info;
330
331 ti->ti_flags |= NILFS_TI_WRITER;
332 nilfs_segctor_do_immediate_flush(sci);
333 ti->ti_flags &= ~NILFS_TI_WRITER;
334 }
335 downgrade_write(&nilfs->ns_segctor_sem);
336}
337
338static void nilfs_transaction_lock(struct super_block *sb,
339 struct nilfs_transaction_info *ti,
340 int gcflag)
341{
342 struct nilfs_transaction_info *cur_ti = current->journal_info;
343 struct the_nilfs *nilfs = sb->s_fs_info;
344 struct nilfs_sc_info *sci = nilfs->ns_writer;
345
346 WARN_ON(cur_ti);
347 ti->ti_flags = NILFS_TI_WRITER;
348 ti->ti_count = 0;
349 ti->ti_save = cur_ti;
350 ti->ti_magic = NILFS_TI_MAGIC;
351 current->journal_info = ti;
352
353 for (;;) {
354 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
355 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
356
357 down_write(&nilfs->ns_segctor_sem);
358 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
359 break;
360
361 nilfs_segctor_do_immediate_flush(sci);
362
363 up_write(&nilfs->ns_segctor_sem);
364 cond_resched();
365 }
366 if (gcflag)
367 ti->ti_flags |= NILFS_TI_GC;
368
369 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
370 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
371}
372
373static void nilfs_transaction_unlock(struct super_block *sb)
374{
375 struct nilfs_transaction_info *ti = current->journal_info;
376 struct the_nilfs *nilfs = sb->s_fs_info;
377
378 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
379 BUG_ON(ti->ti_count > 0);
380
381 up_write(&nilfs->ns_segctor_sem);
382 current->journal_info = ti->ti_save;
383
384 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
385 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
386}
387
388static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
389 struct nilfs_segsum_pointer *ssp,
390 unsigned int bytes)
391{
392 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
393 unsigned int blocksize = sci->sc_super->s_blocksize;
394 void *p;
395
396 if (unlikely(ssp->offset + bytes > blocksize)) {
397 ssp->offset = 0;
398 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
399 &segbuf->sb_segsum_buffers));
400 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
401 }
402 p = ssp->bh->b_data + ssp->offset;
403 ssp->offset += bytes;
404 return p;
405}
406
407/**
408 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
409 * @sci: nilfs_sc_info
410 */
411static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
412{
413 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
414 struct buffer_head *sumbh;
415 unsigned int sumbytes;
416 unsigned int flags = 0;
417 int err;
418
419 if (nilfs_doing_gc())
420 flags = NILFS_SS_GC;
421 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
422 if (unlikely(err))
423 return err;
424
425 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
426 sumbytes = segbuf->sb_sum.sumbytes;
427 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
428 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
429 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
430 return 0;
431}
432
433/**
434 * nilfs_segctor_zeropad_segsum - zero pad the rest of the segment summary area
435 * @sci: segment constructor object
436 *
437 * nilfs_segctor_zeropad_segsum() zero-fills unallocated space at the end of
438 * the current segment summary block.
439 */
440static void nilfs_segctor_zeropad_segsum(struct nilfs_sc_info *sci)
441{
442 struct nilfs_segsum_pointer *ssp;
443
444 ssp = sci->sc_blk_cnt > 0 ? &sci->sc_binfo_ptr : &sci->sc_finfo_ptr;
445 if (ssp->offset < ssp->bh->b_size)
446 memset(ssp->bh->b_data + ssp->offset, 0,
447 ssp->bh->b_size - ssp->offset);
448}
449
450static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
451{
452 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
453 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
454 return -E2BIG; /*
455 * The current segment is filled up
456 * (internal code)
457 */
458 nilfs_segctor_zeropad_segsum(sci);
459 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
460 return nilfs_segctor_reset_segment_buffer(sci);
461}
462
463static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
464{
465 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
466 int err;
467
468 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
469 err = nilfs_segctor_feed_segment(sci);
470 if (err)
471 return err;
472 segbuf = sci->sc_curseg;
473 }
474 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
475 if (likely(!err))
476 segbuf->sb_sum.flags |= NILFS_SS_SR;
477 return err;
478}
479
480/*
481 * Functions for making segment summary and payloads
482 */
483static int nilfs_segctor_segsum_block_required(
484 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
485 unsigned int binfo_size)
486{
487 unsigned int blocksize = sci->sc_super->s_blocksize;
488 /* Size of finfo and binfo is enough small against blocksize */
489
490 return ssp->offset + binfo_size +
491 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
492 blocksize;
493}
494
495static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
496 struct inode *inode)
497{
498 sci->sc_curseg->sb_sum.nfinfo++;
499 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
500 nilfs_segctor_map_segsum_entry(
501 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
502
503 if (NILFS_I(inode)->i_root &&
504 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
505 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
506 /* skip finfo */
507}
508
509static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
510 struct inode *inode)
511{
512 struct nilfs_finfo *finfo;
513 struct nilfs_inode_info *ii;
514 struct nilfs_segment_buffer *segbuf;
515 __u64 cno;
516
517 if (sci->sc_blk_cnt == 0)
518 return;
519
520 ii = NILFS_I(inode);
521
522 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
523 cno = ii->i_cno;
524 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
525 cno = 0;
526 else
527 cno = sci->sc_cno;
528
529 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
530 sizeof(*finfo));
531 finfo->fi_ino = cpu_to_le64(inode->i_ino);
532 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
533 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
534 finfo->fi_cno = cpu_to_le64(cno);
535
536 segbuf = sci->sc_curseg;
537 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
538 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
539 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
540 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
541}
542
543static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
544 struct buffer_head *bh,
545 struct inode *inode,
546 unsigned int binfo_size)
547{
548 struct nilfs_segment_buffer *segbuf;
549 int required, err = 0;
550
551 retry:
552 segbuf = sci->sc_curseg;
553 required = nilfs_segctor_segsum_block_required(
554 sci, &sci->sc_binfo_ptr, binfo_size);
555 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
556 nilfs_segctor_end_finfo(sci, inode);
557 err = nilfs_segctor_feed_segment(sci);
558 if (err)
559 return err;
560 goto retry;
561 }
562 if (unlikely(required)) {
563 nilfs_segctor_zeropad_segsum(sci);
564 err = nilfs_segbuf_extend_segsum(segbuf);
565 if (unlikely(err))
566 goto failed;
567 }
568 if (sci->sc_blk_cnt == 0)
569 nilfs_segctor_begin_finfo(sci, inode);
570
571 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
572 /* Substitution to vblocknr is delayed until update_blocknr() */
573 nilfs_segbuf_add_file_buffer(segbuf, bh);
574 sci->sc_blk_cnt++;
575 failed:
576 return err;
577}
578
579/*
580 * Callback functions that enumerate, mark, and collect dirty blocks
581 */
582static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
583 struct buffer_head *bh, struct inode *inode)
584{
585 int err;
586
587 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
588 if (err < 0)
589 return err;
590
591 err = nilfs_segctor_add_file_block(sci, bh, inode,
592 sizeof(struct nilfs_binfo_v));
593 if (!err)
594 sci->sc_datablk_cnt++;
595 return err;
596}
597
598static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
599 struct buffer_head *bh,
600 struct inode *inode)
601{
602 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
603}
604
605static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
606 struct buffer_head *bh,
607 struct inode *inode)
608{
609 WARN_ON(!buffer_dirty(bh));
610 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
611}
612
613static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
614 struct nilfs_segsum_pointer *ssp,
615 union nilfs_binfo *binfo)
616{
617 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
618 sci, ssp, sizeof(*binfo_v));
619 *binfo_v = binfo->bi_v;
620}
621
622static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
623 struct nilfs_segsum_pointer *ssp,
624 union nilfs_binfo *binfo)
625{
626 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
627 sci, ssp, sizeof(*vblocknr));
628 *vblocknr = binfo->bi_v.bi_vblocknr;
629}
630
631static const struct nilfs_sc_operations nilfs_sc_file_ops = {
632 .collect_data = nilfs_collect_file_data,
633 .collect_node = nilfs_collect_file_node,
634 .collect_bmap = nilfs_collect_file_bmap,
635 .write_data_binfo = nilfs_write_file_data_binfo,
636 .write_node_binfo = nilfs_write_file_node_binfo,
637};
638
639static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
640 struct buffer_head *bh, struct inode *inode)
641{
642 int err;
643
644 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
645 if (err < 0)
646 return err;
647
648 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
649 if (!err)
650 sci->sc_datablk_cnt++;
651 return err;
652}
653
654static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
655 struct buffer_head *bh, struct inode *inode)
656{
657 WARN_ON(!buffer_dirty(bh));
658 return nilfs_segctor_add_file_block(sci, bh, inode,
659 sizeof(struct nilfs_binfo_dat));
660}
661
662static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
663 struct nilfs_segsum_pointer *ssp,
664 union nilfs_binfo *binfo)
665{
666 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
667 sizeof(*blkoff));
668 *blkoff = binfo->bi_dat.bi_blkoff;
669}
670
671static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
672 struct nilfs_segsum_pointer *ssp,
673 union nilfs_binfo *binfo)
674{
675 struct nilfs_binfo_dat *binfo_dat =
676 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
677 *binfo_dat = binfo->bi_dat;
678}
679
680static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
681 .collect_data = nilfs_collect_dat_data,
682 .collect_node = nilfs_collect_file_node,
683 .collect_bmap = nilfs_collect_dat_bmap,
684 .write_data_binfo = nilfs_write_dat_data_binfo,
685 .write_node_binfo = nilfs_write_dat_node_binfo,
686};
687
688static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
689 .collect_data = nilfs_collect_file_data,
690 .collect_node = NULL,
691 .collect_bmap = NULL,
692 .write_data_binfo = nilfs_write_file_data_binfo,
693 .write_node_binfo = NULL,
694};
695
696static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
697 struct list_head *listp,
698 size_t nlimit,
699 loff_t start, loff_t end)
700{
701 struct address_space *mapping = inode->i_mapping;
702 struct folio_batch fbatch;
703 pgoff_t index = 0, last = ULONG_MAX;
704 size_t ndirties = 0;
705 int i;
706
707 if (unlikely(start != 0 || end != LLONG_MAX)) {
708 /*
709 * A valid range is given for sync-ing data pages. The
710 * range is rounded to per-page; extra dirty buffers
711 * may be included if blocksize < pagesize.
712 */
713 index = start >> PAGE_SHIFT;
714 last = end >> PAGE_SHIFT;
715 }
716 folio_batch_init(&fbatch);
717 repeat:
718 if (unlikely(index > last) ||
719 !filemap_get_folios_tag(mapping, &index, last,
720 PAGECACHE_TAG_DIRTY, &fbatch))
721 return ndirties;
722
723 for (i = 0; i < folio_batch_count(&fbatch); i++) {
724 struct buffer_head *bh, *head;
725 struct folio *folio = fbatch.folios[i];
726
727 folio_lock(folio);
728 if (unlikely(folio->mapping != mapping)) {
729 /* Exclude folios removed from the address space */
730 folio_unlock(folio);
731 continue;
732 }
733 head = folio_buffers(folio);
734 if (!head)
735 head = create_empty_buffers(folio,
736 i_blocksize(inode), 0);
737 folio_unlock(folio);
738
739 bh = head;
740 do {
741 if (!buffer_dirty(bh) || buffer_async_write(bh))
742 continue;
743 get_bh(bh);
744 list_add_tail(&bh->b_assoc_buffers, listp);
745 ndirties++;
746 if (unlikely(ndirties >= nlimit)) {
747 folio_batch_release(&fbatch);
748 cond_resched();
749 return ndirties;
750 }
751 } while (bh = bh->b_this_page, bh != head);
752 }
753 folio_batch_release(&fbatch);
754 cond_resched();
755 goto repeat;
756}
757
758static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
759 struct list_head *listp)
760{
761 struct nilfs_inode_info *ii = NILFS_I(inode);
762 struct inode *btnc_inode = ii->i_assoc_inode;
763 struct folio_batch fbatch;
764 struct buffer_head *bh, *head;
765 unsigned int i;
766 pgoff_t index = 0;
767
768 if (!btnc_inode)
769 return;
770 folio_batch_init(&fbatch);
771
772 while (filemap_get_folios_tag(btnc_inode->i_mapping, &index,
773 (pgoff_t)-1, PAGECACHE_TAG_DIRTY, &fbatch)) {
774 for (i = 0; i < folio_batch_count(&fbatch); i++) {
775 bh = head = folio_buffers(fbatch.folios[i]);
776 do {
777 if (buffer_dirty(bh) &&
778 !buffer_async_write(bh)) {
779 get_bh(bh);
780 list_add_tail(&bh->b_assoc_buffers,
781 listp);
782 }
783 bh = bh->b_this_page;
784 } while (bh != head);
785 }
786 folio_batch_release(&fbatch);
787 cond_resched();
788 }
789}
790
791static void nilfs_dispose_list(struct the_nilfs *nilfs,
792 struct list_head *head, int force)
793{
794 struct nilfs_inode_info *ii, *n;
795 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
796 unsigned int nv = 0;
797
798 while (!list_empty(head)) {
799 spin_lock(&nilfs->ns_inode_lock);
800 list_for_each_entry_safe(ii, n, head, i_dirty) {
801 list_del_init(&ii->i_dirty);
802 if (force) {
803 if (unlikely(ii->i_bh)) {
804 brelse(ii->i_bh);
805 ii->i_bh = NULL;
806 }
807 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
808 set_bit(NILFS_I_QUEUED, &ii->i_state);
809 list_add_tail(&ii->i_dirty,
810 &nilfs->ns_dirty_files);
811 continue;
812 }
813 ivec[nv++] = ii;
814 if (nv == SC_N_INODEVEC)
815 break;
816 }
817 spin_unlock(&nilfs->ns_inode_lock);
818
819 for (pii = ivec; nv > 0; pii++, nv--)
820 iput(&(*pii)->vfs_inode);
821 }
822}
823
824static void nilfs_iput_work_func(struct work_struct *work)
825{
826 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
827 sc_iput_work);
828 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
829
830 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
831}
832
833static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
834 struct nilfs_root *root)
835{
836 int ret = 0;
837
838 if (nilfs_mdt_fetch_dirty(root->ifile))
839 ret++;
840 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
841 ret++;
842 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
843 ret++;
844 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
845 ret++;
846 return ret;
847}
848
849static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
850{
851 return list_empty(&sci->sc_dirty_files) &&
852 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
853 sci->sc_nfreesegs == 0 &&
854 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
855}
856
857static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
858{
859 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
860 int ret = 0;
861
862 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
863 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
864
865 spin_lock(&nilfs->ns_inode_lock);
866 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
867 ret++;
868
869 spin_unlock(&nilfs->ns_inode_lock);
870 return ret;
871}
872
873static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
874{
875 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
876
877 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
878 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
879 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
880 nilfs_mdt_clear_dirty(nilfs->ns_dat);
881}
882
883static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
884{
885 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
886 struct buffer_head *bh_cp;
887 struct nilfs_checkpoint *raw_cp;
888 int err;
889
890 /* XXX: this interface will be changed */
891 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
892 &raw_cp, &bh_cp);
893 if (likely(!err)) {
894 /*
895 * The following code is duplicated with cpfile. But, it is
896 * needed to collect the checkpoint even if it was not newly
897 * created.
898 */
899 mark_buffer_dirty(bh_cp);
900 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
901 nilfs_cpfile_put_checkpoint(
902 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
903 } else if (err == -EINVAL || err == -ENOENT) {
904 nilfs_error(sci->sc_super,
905 "checkpoint creation failed due to metadata corruption.");
906 err = -EIO;
907 }
908 return err;
909}
910
911static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
912{
913 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
914 struct buffer_head *bh_cp;
915 struct nilfs_checkpoint *raw_cp;
916 int err;
917
918 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
919 &raw_cp, &bh_cp);
920 if (unlikely(err)) {
921 if (err == -EINVAL || err == -ENOENT) {
922 nilfs_error(sci->sc_super,
923 "checkpoint finalization failed due to metadata corruption.");
924 err = -EIO;
925 }
926 goto failed_ibh;
927 }
928 raw_cp->cp_snapshot_list.ssl_next = 0;
929 raw_cp->cp_snapshot_list.ssl_prev = 0;
930 raw_cp->cp_inodes_count =
931 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
932 raw_cp->cp_blocks_count =
933 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
934 raw_cp->cp_nblk_inc =
935 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
936 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
937 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
938
939 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
940 nilfs_checkpoint_clear_minor(raw_cp);
941 else
942 nilfs_checkpoint_set_minor(raw_cp);
943
944 nilfs_write_inode_common(sci->sc_root->ifile,
945 &raw_cp->cp_ifile_inode, 1);
946 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
947 return 0;
948
949 failed_ibh:
950 return err;
951}
952
953static void nilfs_fill_in_file_bmap(struct inode *ifile,
954 struct nilfs_inode_info *ii)
955
956{
957 struct buffer_head *ibh;
958 struct nilfs_inode *raw_inode;
959
960 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
961 ibh = ii->i_bh;
962 BUG_ON(!ibh);
963 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
964 ibh);
965 nilfs_bmap_write(ii->i_bmap, raw_inode);
966 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
967 }
968}
969
970static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
971{
972 struct nilfs_inode_info *ii;
973
974 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
975 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
976 set_bit(NILFS_I_COLLECTED, &ii->i_state);
977 }
978}
979
980static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
981 struct the_nilfs *nilfs)
982{
983 struct buffer_head *bh_sr;
984 struct nilfs_super_root *raw_sr;
985 unsigned int isz, srsz;
986
987 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
988
989 lock_buffer(bh_sr);
990 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
991 isz = nilfs->ns_inode_size;
992 srsz = NILFS_SR_BYTES(isz);
993
994 raw_sr->sr_sum = 0; /* Ensure initialization within this update */
995 raw_sr->sr_bytes = cpu_to_le16(srsz);
996 raw_sr->sr_nongc_ctime
997 = cpu_to_le64(nilfs_doing_gc() ?
998 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
999 raw_sr->sr_flags = 0;
1000
1001 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
1002 NILFS_SR_DAT_OFFSET(isz), 1);
1003 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
1004 NILFS_SR_CPFILE_OFFSET(isz), 1);
1005 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
1006 NILFS_SR_SUFILE_OFFSET(isz), 1);
1007 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
1008 set_buffer_uptodate(bh_sr);
1009 unlock_buffer(bh_sr);
1010}
1011
1012static void nilfs_redirty_inodes(struct list_head *head)
1013{
1014 struct nilfs_inode_info *ii;
1015
1016 list_for_each_entry(ii, head, i_dirty) {
1017 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
1018 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
1019 }
1020}
1021
1022static void nilfs_drop_collected_inodes(struct list_head *head)
1023{
1024 struct nilfs_inode_info *ii;
1025
1026 list_for_each_entry(ii, head, i_dirty) {
1027 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
1028 continue;
1029
1030 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
1031 set_bit(NILFS_I_UPDATED, &ii->i_state);
1032 }
1033}
1034
1035static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1036 struct inode *inode,
1037 struct list_head *listp,
1038 int (*collect)(struct nilfs_sc_info *,
1039 struct buffer_head *,
1040 struct inode *))
1041{
1042 struct buffer_head *bh, *n;
1043 int err = 0;
1044
1045 if (collect) {
1046 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1047 list_del_init(&bh->b_assoc_buffers);
1048 err = collect(sci, bh, inode);
1049 brelse(bh);
1050 if (unlikely(err))
1051 goto dispose_buffers;
1052 }
1053 return 0;
1054 }
1055
1056 dispose_buffers:
1057 while (!list_empty(listp)) {
1058 bh = list_first_entry(listp, struct buffer_head,
1059 b_assoc_buffers);
1060 list_del_init(&bh->b_assoc_buffers);
1061 brelse(bh);
1062 }
1063 return err;
1064}
1065
1066static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1067{
1068 /* Remaining number of blocks within segment buffer */
1069 return sci->sc_segbuf_nblocks -
1070 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1071}
1072
1073static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1074 struct inode *inode,
1075 const struct nilfs_sc_operations *sc_ops)
1076{
1077 LIST_HEAD(data_buffers);
1078 LIST_HEAD(node_buffers);
1079 int err;
1080
1081 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1082 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1083
1084 n = nilfs_lookup_dirty_data_buffers(
1085 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1086 if (n > rest) {
1087 err = nilfs_segctor_apply_buffers(
1088 sci, inode, &data_buffers,
1089 sc_ops->collect_data);
1090 BUG_ON(!err); /* always receive -E2BIG or true error */
1091 goto break_or_fail;
1092 }
1093 }
1094 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1095
1096 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1097 err = nilfs_segctor_apply_buffers(
1098 sci, inode, &data_buffers, sc_ops->collect_data);
1099 if (unlikely(err)) {
1100 /* dispose node list */
1101 nilfs_segctor_apply_buffers(
1102 sci, inode, &node_buffers, NULL);
1103 goto break_or_fail;
1104 }
1105 sci->sc_stage.flags |= NILFS_CF_NODE;
1106 }
1107 /* Collect node */
1108 err = nilfs_segctor_apply_buffers(
1109 sci, inode, &node_buffers, sc_ops->collect_node);
1110 if (unlikely(err))
1111 goto break_or_fail;
1112
1113 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1114 err = nilfs_segctor_apply_buffers(
1115 sci, inode, &node_buffers, sc_ops->collect_bmap);
1116 if (unlikely(err))
1117 goto break_or_fail;
1118
1119 nilfs_segctor_end_finfo(sci, inode);
1120 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1121
1122 break_or_fail:
1123 return err;
1124}
1125
1126static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1127 struct inode *inode)
1128{
1129 LIST_HEAD(data_buffers);
1130 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1131 int err;
1132
1133 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1134 sci->sc_dsync_start,
1135 sci->sc_dsync_end);
1136
1137 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1138 nilfs_collect_file_data);
1139 if (!err) {
1140 nilfs_segctor_end_finfo(sci, inode);
1141 BUG_ON(n > rest);
1142 /* always receive -E2BIG or true error if n > rest */
1143 }
1144 return err;
1145}
1146
1147static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1148{
1149 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1150 struct list_head *head;
1151 struct nilfs_inode_info *ii;
1152 size_t ndone;
1153 int err = 0;
1154
1155 switch (nilfs_sc_cstage_get(sci)) {
1156 case NILFS_ST_INIT:
1157 /* Pre-processes */
1158 sci->sc_stage.flags = 0;
1159
1160 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1161 sci->sc_nblk_inc = 0;
1162 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1163 if (mode == SC_LSEG_DSYNC) {
1164 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1165 goto dsync_mode;
1166 }
1167 }
1168
1169 sci->sc_stage.dirty_file_ptr = NULL;
1170 sci->sc_stage.gc_inode_ptr = NULL;
1171 if (mode == SC_FLUSH_DAT) {
1172 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1173 goto dat_stage;
1174 }
1175 nilfs_sc_cstage_inc(sci);
1176 fallthrough;
1177 case NILFS_ST_GC:
1178 if (nilfs_doing_gc()) {
1179 head = &sci->sc_gc_inodes;
1180 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1181 head, i_dirty);
1182 list_for_each_entry_continue(ii, head, i_dirty) {
1183 err = nilfs_segctor_scan_file(
1184 sci, &ii->vfs_inode,
1185 &nilfs_sc_file_ops);
1186 if (unlikely(err)) {
1187 sci->sc_stage.gc_inode_ptr = list_entry(
1188 ii->i_dirty.prev,
1189 struct nilfs_inode_info,
1190 i_dirty);
1191 goto break_or_fail;
1192 }
1193 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1194 }
1195 sci->sc_stage.gc_inode_ptr = NULL;
1196 }
1197 nilfs_sc_cstage_inc(sci);
1198 fallthrough;
1199 case NILFS_ST_FILE:
1200 head = &sci->sc_dirty_files;
1201 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1202 i_dirty);
1203 list_for_each_entry_continue(ii, head, i_dirty) {
1204 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1205
1206 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1207 &nilfs_sc_file_ops);
1208 if (unlikely(err)) {
1209 sci->sc_stage.dirty_file_ptr =
1210 list_entry(ii->i_dirty.prev,
1211 struct nilfs_inode_info,
1212 i_dirty);
1213 goto break_or_fail;
1214 }
1215 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1216 /* XXX: required ? */
1217 }
1218 sci->sc_stage.dirty_file_ptr = NULL;
1219 if (mode == SC_FLUSH_FILE) {
1220 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1221 return 0;
1222 }
1223 nilfs_sc_cstage_inc(sci);
1224 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1225 fallthrough;
1226 case NILFS_ST_IFILE:
1227 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1228 &nilfs_sc_file_ops);
1229 if (unlikely(err))
1230 break;
1231 nilfs_sc_cstage_inc(sci);
1232 /* Creating a checkpoint */
1233 err = nilfs_segctor_create_checkpoint(sci);
1234 if (unlikely(err))
1235 break;
1236 fallthrough;
1237 case NILFS_ST_CPFILE:
1238 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1239 &nilfs_sc_file_ops);
1240 if (unlikely(err))
1241 break;
1242 nilfs_sc_cstage_inc(sci);
1243 fallthrough;
1244 case NILFS_ST_SUFILE:
1245 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1246 sci->sc_nfreesegs, &ndone);
1247 if (unlikely(err)) {
1248 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1249 sci->sc_freesegs, ndone,
1250 NULL);
1251 break;
1252 }
1253 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1254
1255 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1256 &nilfs_sc_file_ops);
1257 if (unlikely(err))
1258 break;
1259 nilfs_sc_cstage_inc(sci);
1260 fallthrough;
1261 case NILFS_ST_DAT:
1262 dat_stage:
1263 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1264 &nilfs_sc_dat_ops);
1265 if (unlikely(err))
1266 break;
1267 if (mode == SC_FLUSH_DAT) {
1268 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1269 return 0;
1270 }
1271 nilfs_sc_cstage_inc(sci);
1272 fallthrough;
1273 case NILFS_ST_SR:
1274 if (mode == SC_LSEG_SR) {
1275 /* Appending a super root */
1276 err = nilfs_segctor_add_super_root(sci);
1277 if (unlikely(err))
1278 break;
1279 }
1280 /* End of a logical segment */
1281 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1282 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1283 return 0;
1284 case NILFS_ST_DSYNC:
1285 dsync_mode:
1286 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1287 ii = sci->sc_dsync_inode;
1288 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1289 break;
1290
1291 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1292 if (unlikely(err))
1293 break;
1294 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1295 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1296 return 0;
1297 case NILFS_ST_DONE:
1298 return 0;
1299 default:
1300 BUG();
1301 }
1302
1303 break_or_fail:
1304 return err;
1305}
1306
1307/**
1308 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1309 * @sci: nilfs_sc_info
1310 * @nilfs: nilfs object
1311 */
1312static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1313 struct the_nilfs *nilfs)
1314{
1315 struct nilfs_segment_buffer *segbuf, *prev;
1316 __u64 nextnum;
1317 int err, alloc = 0;
1318
1319 segbuf = nilfs_segbuf_new(sci->sc_super);
1320 if (unlikely(!segbuf))
1321 return -ENOMEM;
1322
1323 if (list_empty(&sci->sc_write_logs)) {
1324 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1325 nilfs->ns_pseg_offset, nilfs);
1326 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1327 nilfs_shift_to_next_segment(nilfs);
1328 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1329 }
1330
1331 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1332 nextnum = nilfs->ns_nextnum;
1333
1334 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1335 /* Start from the head of a new full segment */
1336 alloc++;
1337 } else {
1338 /* Continue logs */
1339 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1340 nilfs_segbuf_map_cont(segbuf, prev);
1341 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1342 nextnum = prev->sb_nextnum;
1343
1344 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1345 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1346 segbuf->sb_sum.seg_seq++;
1347 alloc++;
1348 }
1349 }
1350
1351 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1352 if (err)
1353 goto failed;
1354
1355 if (alloc) {
1356 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1357 if (err)
1358 goto failed;
1359 }
1360 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1361
1362 BUG_ON(!list_empty(&sci->sc_segbufs));
1363 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1364 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1365 return 0;
1366
1367 failed:
1368 nilfs_segbuf_free(segbuf);
1369 return err;
1370}
1371
1372static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1373 struct the_nilfs *nilfs, int nadd)
1374{
1375 struct nilfs_segment_buffer *segbuf, *prev;
1376 struct inode *sufile = nilfs->ns_sufile;
1377 __u64 nextnextnum;
1378 LIST_HEAD(list);
1379 int err, ret, i;
1380
1381 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1382 /*
1383 * Since the segment specified with nextnum might be allocated during
1384 * the previous construction, the buffer including its segusage may
1385 * not be dirty. The following call ensures that the buffer is dirty
1386 * and will pin the buffer on memory until the sufile is written.
1387 */
1388 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1389 if (unlikely(err))
1390 return err;
1391
1392 for (i = 0; i < nadd; i++) {
1393 /* extend segment info */
1394 err = -ENOMEM;
1395 segbuf = nilfs_segbuf_new(sci->sc_super);
1396 if (unlikely(!segbuf))
1397 goto failed;
1398
1399 /* map this buffer to region of segment on-disk */
1400 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1401 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1402
1403 /* allocate the next next full segment */
1404 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1405 if (unlikely(err))
1406 goto failed_segbuf;
1407
1408 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1409 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1410
1411 list_add_tail(&segbuf->sb_list, &list);
1412 prev = segbuf;
1413 }
1414 list_splice_tail(&list, &sci->sc_segbufs);
1415 return 0;
1416
1417 failed_segbuf:
1418 nilfs_segbuf_free(segbuf);
1419 failed:
1420 list_for_each_entry(segbuf, &list, sb_list) {
1421 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1422 WARN_ON(ret); /* never fails */
1423 }
1424 nilfs_destroy_logs(&list);
1425 return err;
1426}
1427
1428static void nilfs_free_incomplete_logs(struct list_head *logs,
1429 struct the_nilfs *nilfs)
1430{
1431 struct nilfs_segment_buffer *segbuf, *prev;
1432 struct inode *sufile = nilfs->ns_sufile;
1433 int ret;
1434
1435 segbuf = NILFS_FIRST_SEGBUF(logs);
1436 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1437 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1438 WARN_ON(ret); /* never fails */
1439 }
1440 if (atomic_read(&segbuf->sb_err)) {
1441 /* Case 1: The first segment failed */
1442 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1443 /*
1444 * Case 1a: Partial segment appended into an existing
1445 * segment
1446 */
1447 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1448 segbuf->sb_fseg_end);
1449 else /* Case 1b: New full segment */
1450 set_nilfs_discontinued(nilfs);
1451 }
1452
1453 prev = segbuf;
1454 list_for_each_entry_continue(segbuf, logs, sb_list) {
1455 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1456 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1457 WARN_ON(ret); /* never fails */
1458 }
1459 if (atomic_read(&segbuf->sb_err) &&
1460 segbuf->sb_segnum != nilfs->ns_nextnum)
1461 /* Case 2: extended segment (!= next) failed */
1462 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1463 prev = segbuf;
1464 }
1465}
1466
1467static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1468 struct inode *sufile)
1469{
1470 struct nilfs_segment_buffer *segbuf;
1471 unsigned long live_blocks;
1472 int ret;
1473
1474 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1475 live_blocks = segbuf->sb_sum.nblocks +
1476 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1477 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1478 live_blocks,
1479 sci->sc_seg_ctime);
1480 WARN_ON(ret); /* always succeed because the segusage is dirty */
1481 }
1482}
1483
1484static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1485{
1486 struct nilfs_segment_buffer *segbuf;
1487 int ret;
1488
1489 segbuf = NILFS_FIRST_SEGBUF(logs);
1490 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1491 segbuf->sb_pseg_start -
1492 segbuf->sb_fseg_start, 0);
1493 WARN_ON(ret); /* always succeed because the segusage is dirty */
1494
1495 list_for_each_entry_continue(segbuf, logs, sb_list) {
1496 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1497 0, 0);
1498 WARN_ON(ret); /* always succeed */
1499 }
1500}
1501
1502static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1503 struct nilfs_segment_buffer *last,
1504 struct inode *sufile)
1505{
1506 struct nilfs_segment_buffer *segbuf = last;
1507 int ret;
1508
1509 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1510 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1511 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1512 WARN_ON(ret);
1513 }
1514 nilfs_truncate_logs(&sci->sc_segbufs, last);
1515}
1516
1517
1518static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1519 struct the_nilfs *nilfs, int mode)
1520{
1521 struct nilfs_cstage prev_stage = sci->sc_stage;
1522 int err, nadd = 1;
1523
1524 /* Collection retry loop */
1525 for (;;) {
1526 sci->sc_nblk_this_inc = 0;
1527 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1528
1529 err = nilfs_segctor_reset_segment_buffer(sci);
1530 if (unlikely(err))
1531 goto failed;
1532
1533 err = nilfs_segctor_collect_blocks(sci, mode);
1534 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1535 if (!err)
1536 break;
1537
1538 if (unlikely(err != -E2BIG))
1539 goto failed;
1540
1541 /* The current segment is filled up */
1542 if (mode != SC_LSEG_SR ||
1543 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1544 break;
1545
1546 nilfs_clear_logs(&sci->sc_segbufs);
1547
1548 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1549 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1550 sci->sc_freesegs,
1551 sci->sc_nfreesegs,
1552 NULL);
1553 WARN_ON(err); /* do not happen */
1554 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1555 }
1556
1557 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1558 if (unlikely(err))
1559 return err;
1560
1561 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1562 sci->sc_stage = prev_stage;
1563 }
1564 nilfs_segctor_zeropad_segsum(sci);
1565 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1566 return 0;
1567
1568 failed:
1569 return err;
1570}
1571
1572static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1573 struct buffer_head *new_bh)
1574{
1575 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1576
1577 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1578 /* The caller must release old_bh */
1579}
1580
1581static int
1582nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1583 struct nilfs_segment_buffer *segbuf,
1584 int mode)
1585{
1586 struct inode *inode = NULL;
1587 sector_t blocknr;
1588 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1589 unsigned long nblocks = 0, ndatablk = 0;
1590 const struct nilfs_sc_operations *sc_op = NULL;
1591 struct nilfs_segsum_pointer ssp;
1592 struct nilfs_finfo *finfo = NULL;
1593 union nilfs_binfo binfo;
1594 struct buffer_head *bh, *bh_org;
1595 ino_t ino = 0;
1596 int err = 0;
1597
1598 if (!nfinfo)
1599 goto out;
1600
1601 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1602 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1603 ssp.offset = sizeof(struct nilfs_segment_summary);
1604
1605 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1606 if (bh == segbuf->sb_super_root)
1607 break;
1608 if (!finfo) {
1609 finfo = nilfs_segctor_map_segsum_entry(
1610 sci, &ssp, sizeof(*finfo));
1611 ino = le64_to_cpu(finfo->fi_ino);
1612 nblocks = le32_to_cpu(finfo->fi_nblocks);
1613 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1614
1615 inode = bh->b_folio->mapping->host;
1616
1617 if (mode == SC_LSEG_DSYNC)
1618 sc_op = &nilfs_sc_dsync_ops;
1619 else if (ino == NILFS_DAT_INO)
1620 sc_op = &nilfs_sc_dat_ops;
1621 else /* file blocks */
1622 sc_op = &nilfs_sc_file_ops;
1623 }
1624 bh_org = bh;
1625 get_bh(bh_org);
1626 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1627 &binfo);
1628 if (bh != bh_org)
1629 nilfs_list_replace_buffer(bh_org, bh);
1630 brelse(bh_org);
1631 if (unlikely(err))
1632 goto failed_bmap;
1633
1634 if (ndatablk > 0)
1635 sc_op->write_data_binfo(sci, &ssp, &binfo);
1636 else
1637 sc_op->write_node_binfo(sci, &ssp, &binfo);
1638
1639 blocknr++;
1640 if (--nblocks == 0) {
1641 finfo = NULL;
1642 if (--nfinfo == 0)
1643 break;
1644 } else if (ndatablk > 0)
1645 ndatablk--;
1646 }
1647 out:
1648 return 0;
1649
1650 failed_bmap:
1651 return err;
1652}
1653
1654static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1655{
1656 struct nilfs_segment_buffer *segbuf;
1657 int err;
1658
1659 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1660 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1661 if (unlikely(err))
1662 return err;
1663 nilfs_segbuf_fill_in_segsum(segbuf);
1664 }
1665 return 0;
1666}
1667
1668static void nilfs_begin_folio_io(struct folio *folio)
1669{
1670 if (!folio || folio_test_writeback(folio))
1671 /*
1672 * For split b-tree node pages, this function may be called
1673 * twice. We ignore the 2nd or later calls by this check.
1674 */
1675 return;
1676
1677 folio_lock(folio);
1678 folio_clear_dirty_for_io(folio);
1679 folio_start_writeback(folio);
1680 folio_unlock(folio);
1681}
1682
1683static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1684{
1685 struct nilfs_segment_buffer *segbuf;
1686 struct folio *bd_folio = NULL, *fs_folio = NULL;
1687
1688 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1689 struct buffer_head *bh;
1690
1691 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1692 b_assoc_buffers) {
1693 if (bh->b_folio != bd_folio) {
1694 if (bd_folio) {
1695 folio_lock(bd_folio);
1696 folio_clear_dirty_for_io(bd_folio);
1697 folio_start_writeback(bd_folio);
1698 folio_unlock(bd_folio);
1699 }
1700 bd_folio = bh->b_folio;
1701 }
1702 }
1703
1704 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1705 b_assoc_buffers) {
1706 if (bh == segbuf->sb_super_root) {
1707 if (bh->b_folio != bd_folio) {
1708 folio_lock(bd_folio);
1709 folio_clear_dirty_for_io(bd_folio);
1710 folio_start_writeback(bd_folio);
1711 folio_unlock(bd_folio);
1712 bd_folio = bh->b_folio;
1713 }
1714 break;
1715 }
1716 set_buffer_async_write(bh);
1717 if (bh->b_folio != fs_folio) {
1718 nilfs_begin_folio_io(fs_folio);
1719 fs_folio = bh->b_folio;
1720 }
1721 }
1722 }
1723 if (bd_folio) {
1724 folio_lock(bd_folio);
1725 folio_clear_dirty_for_io(bd_folio);
1726 folio_start_writeback(bd_folio);
1727 folio_unlock(bd_folio);
1728 }
1729 nilfs_begin_folio_io(fs_folio);
1730}
1731
1732static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1733 struct the_nilfs *nilfs)
1734{
1735 int ret;
1736
1737 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1738 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1739 return ret;
1740}
1741
1742static void nilfs_end_folio_io(struct folio *folio, int err)
1743{
1744 if (!folio)
1745 return;
1746
1747 if (buffer_nilfs_node(folio_buffers(folio)) &&
1748 !folio_test_writeback(folio)) {
1749 /*
1750 * For b-tree node pages, this function may be called twice
1751 * or more because they might be split in a segment.
1752 */
1753 if (folio_test_dirty(folio)) {
1754 /*
1755 * For pages holding split b-tree node buffers, dirty
1756 * flag on the buffers may be cleared discretely.
1757 * In that case, the page is once redirtied for
1758 * remaining buffers, and it must be cancelled if
1759 * all the buffers get cleaned later.
1760 */
1761 folio_lock(folio);
1762 if (nilfs_folio_buffers_clean(folio))
1763 __nilfs_clear_folio_dirty(folio);
1764 folio_unlock(folio);
1765 }
1766 return;
1767 }
1768
1769 if (!err) {
1770 if (!nilfs_folio_buffers_clean(folio))
1771 filemap_dirty_folio(folio->mapping, folio);
1772 folio_clear_error(folio);
1773 } else {
1774 filemap_dirty_folio(folio->mapping, folio);
1775 folio_set_error(folio);
1776 }
1777
1778 folio_end_writeback(folio);
1779}
1780
1781static void nilfs_abort_logs(struct list_head *logs, int err)
1782{
1783 struct nilfs_segment_buffer *segbuf;
1784 struct folio *bd_folio = NULL, *fs_folio = NULL;
1785 struct buffer_head *bh;
1786
1787 if (list_empty(logs))
1788 return;
1789
1790 list_for_each_entry(segbuf, logs, sb_list) {
1791 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1792 b_assoc_buffers) {
1793 clear_buffer_uptodate(bh);
1794 if (bh->b_folio != bd_folio) {
1795 if (bd_folio)
1796 folio_end_writeback(bd_folio);
1797 bd_folio = bh->b_folio;
1798 }
1799 }
1800
1801 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1802 b_assoc_buffers) {
1803 if (bh == segbuf->sb_super_root) {
1804 clear_buffer_uptodate(bh);
1805 if (bh->b_folio != bd_folio) {
1806 folio_end_writeback(bd_folio);
1807 bd_folio = bh->b_folio;
1808 }
1809 break;
1810 }
1811 clear_buffer_async_write(bh);
1812 if (bh->b_folio != fs_folio) {
1813 nilfs_end_folio_io(fs_folio, err);
1814 fs_folio = bh->b_folio;
1815 }
1816 }
1817 }
1818 if (bd_folio)
1819 folio_end_writeback(bd_folio);
1820
1821 nilfs_end_folio_io(fs_folio, err);
1822}
1823
1824static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1825 struct the_nilfs *nilfs, int err)
1826{
1827 LIST_HEAD(logs);
1828 int ret;
1829
1830 list_splice_tail_init(&sci->sc_write_logs, &logs);
1831 ret = nilfs_wait_on_logs(&logs);
1832 nilfs_abort_logs(&logs, ret ? : err);
1833
1834 list_splice_tail_init(&sci->sc_segbufs, &logs);
1835 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1836 nilfs_free_incomplete_logs(&logs, nilfs);
1837
1838 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1839 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1840 sci->sc_freesegs,
1841 sci->sc_nfreesegs,
1842 NULL);
1843 WARN_ON(ret); /* do not happen */
1844 }
1845
1846 nilfs_destroy_logs(&logs);
1847}
1848
1849static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1850 struct nilfs_segment_buffer *segbuf)
1851{
1852 nilfs->ns_segnum = segbuf->sb_segnum;
1853 nilfs->ns_nextnum = segbuf->sb_nextnum;
1854 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1855 + segbuf->sb_sum.nblocks;
1856 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1857 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1858}
1859
1860static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1861{
1862 struct nilfs_segment_buffer *segbuf;
1863 struct folio *bd_folio = NULL, *fs_folio = NULL;
1864 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1865 int update_sr = false;
1866
1867 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1868 struct buffer_head *bh;
1869
1870 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1871 b_assoc_buffers) {
1872 set_buffer_uptodate(bh);
1873 clear_buffer_dirty(bh);
1874 if (bh->b_folio != bd_folio) {
1875 if (bd_folio)
1876 folio_end_writeback(bd_folio);
1877 bd_folio = bh->b_folio;
1878 }
1879 }
1880 /*
1881 * We assume that the buffers which belong to the same folio
1882 * continue over the buffer list.
1883 * Under this assumption, the last BHs of folios is
1884 * identifiable by the discontinuity of bh->b_folio
1885 * (folio != fs_folio).
1886 *
1887 * For B-tree node blocks, however, this assumption is not
1888 * guaranteed. The cleanup code of B-tree node folios needs
1889 * special care.
1890 */
1891 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1892 b_assoc_buffers) {
1893 const unsigned long set_bits = BIT(BH_Uptodate);
1894 const unsigned long clear_bits =
1895 (BIT(BH_Dirty) | BIT(BH_Async_Write) |
1896 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) |
1897 BIT(BH_NILFS_Redirected));
1898
1899 if (bh == segbuf->sb_super_root) {
1900 set_buffer_uptodate(bh);
1901 clear_buffer_dirty(bh);
1902 if (bh->b_folio != bd_folio) {
1903 folio_end_writeback(bd_folio);
1904 bd_folio = bh->b_folio;
1905 }
1906 update_sr = true;
1907 break;
1908 }
1909 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1910 if (bh->b_folio != fs_folio) {
1911 nilfs_end_folio_io(fs_folio, 0);
1912 fs_folio = bh->b_folio;
1913 }
1914 }
1915
1916 if (!nilfs_segbuf_simplex(segbuf)) {
1917 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1918 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1919 sci->sc_lseg_stime = jiffies;
1920 }
1921 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1922 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1923 }
1924 }
1925 /*
1926 * Since folios may continue over multiple segment buffers,
1927 * end of the last folio must be checked outside of the loop.
1928 */
1929 if (bd_folio)
1930 folio_end_writeback(bd_folio);
1931
1932 nilfs_end_folio_io(fs_folio, 0);
1933
1934 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1935
1936 if (nilfs_doing_gc())
1937 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1938 else
1939 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1940
1941 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1942
1943 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1944 nilfs_set_next_segment(nilfs, segbuf);
1945
1946 if (update_sr) {
1947 nilfs->ns_flushed_device = 0;
1948 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1949 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1950
1951 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1952 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1953 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1954 nilfs_segctor_clear_metadata_dirty(sci);
1955 } else
1956 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1957}
1958
1959static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1960{
1961 int ret;
1962
1963 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1964 if (!ret) {
1965 nilfs_segctor_complete_write(sci);
1966 nilfs_destroy_logs(&sci->sc_write_logs);
1967 }
1968 return ret;
1969}
1970
1971static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1972 struct the_nilfs *nilfs)
1973{
1974 struct nilfs_inode_info *ii, *n;
1975 struct inode *ifile = sci->sc_root->ifile;
1976
1977 spin_lock(&nilfs->ns_inode_lock);
1978 retry:
1979 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1980 if (!ii->i_bh) {
1981 struct buffer_head *ibh;
1982 int err;
1983
1984 spin_unlock(&nilfs->ns_inode_lock);
1985 err = nilfs_ifile_get_inode_block(
1986 ifile, ii->vfs_inode.i_ino, &ibh);
1987 if (unlikely(err)) {
1988 nilfs_warn(sci->sc_super,
1989 "log writer: error %d getting inode block (ino=%lu)",
1990 err, ii->vfs_inode.i_ino);
1991 return err;
1992 }
1993 spin_lock(&nilfs->ns_inode_lock);
1994 if (likely(!ii->i_bh))
1995 ii->i_bh = ibh;
1996 else
1997 brelse(ibh);
1998 goto retry;
1999 }
2000
2001 // Always redirty the buffer to avoid race condition
2002 mark_buffer_dirty(ii->i_bh);
2003 nilfs_mdt_mark_dirty(ifile);
2004
2005 clear_bit(NILFS_I_QUEUED, &ii->i_state);
2006 set_bit(NILFS_I_BUSY, &ii->i_state);
2007 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
2008 }
2009 spin_unlock(&nilfs->ns_inode_lock);
2010
2011 return 0;
2012}
2013
2014static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
2015 struct the_nilfs *nilfs)
2016{
2017 struct nilfs_inode_info *ii, *n;
2018 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
2019 int defer_iput = false;
2020
2021 spin_lock(&nilfs->ns_inode_lock);
2022 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2023 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
2024 test_bit(NILFS_I_DIRTY, &ii->i_state))
2025 continue;
2026
2027 clear_bit(NILFS_I_BUSY, &ii->i_state);
2028 brelse(ii->i_bh);
2029 ii->i_bh = NULL;
2030 list_del_init(&ii->i_dirty);
2031 if (!ii->vfs_inode.i_nlink || during_mount) {
2032 /*
2033 * Defer calling iput() to avoid deadlocks if
2034 * i_nlink == 0 or mount is not yet finished.
2035 */
2036 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
2037 defer_iput = true;
2038 } else {
2039 spin_unlock(&nilfs->ns_inode_lock);
2040 iput(&ii->vfs_inode);
2041 spin_lock(&nilfs->ns_inode_lock);
2042 }
2043 }
2044 spin_unlock(&nilfs->ns_inode_lock);
2045
2046 if (defer_iput)
2047 schedule_work(&sci->sc_iput_work);
2048}
2049
2050/*
2051 * Main procedure of segment constructor
2052 */
2053static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2054{
2055 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2056 int err;
2057
2058 if (sb_rdonly(sci->sc_super))
2059 return -EROFS;
2060
2061 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2062 sci->sc_cno = nilfs->ns_cno;
2063
2064 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2065 if (unlikely(err))
2066 goto out;
2067
2068 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2069 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2070
2071 if (nilfs_segctor_clean(sci))
2072 goto out;
2073
2074 do {
2075 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2076
2077 err = nilfs_segctor_begin_construction(sci, nilfs);
2078 if (unlikely(err))
2079 goto out;
2080
2081 /* Update time stamp */
2082 sci->sc_seg_ctime = ktime_get_real_seconds();
2083
2084 err = nilfs_segctor_collect(sci, nilfs, mode);
2085 if (unlikely(err))
2086 goto failed;
2087
2088 /* Avoid empty segment */
2089 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2090 nilfs_segbuf_empty(sci->sc_curseg)) {
2091 nilfs_segctor_abort_construction(sci, nilfs, 1);
2092 goto out;
2093 }
2094
2095 err = nilfs_segctor_assign(sci, mode);
2096 if (unlikely(err))
2097 goto failed;
2098
2099 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2100 nilfs_segctor_fill_in_file_bmap(sci);
2101
2102 if (mode == SC_LSEG_SR &&
2103 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2104 err = nilfs_segctor_fill_in_checkpoint(sci);
2105 if (unlikely(err))
2106 goto failed_to_write;
2107
2108 nilfs_segctor_fill_in_super_root(sci, nilfs);
2109 }
2110 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2111
2112 /* Write partial segments */
2113 nilfs_segctor_prepare_write(sci);
2114
2115 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2116 nilfs->ns_crc_seed);
2117
2118 err = nilfs_segctor_write(sci, nilfs);
2119 if (unlikely(err))
2120 goto failed_to_write;
2121
2122 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2123 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2124 /*
2125 * At this point, we avoid double buffering
2126 * for blocksize < pagesize because page dirty
2127 * flag is turned off during write and dirty
2128 * buffers are not properly collected for
2129 * pages crossing over segments.
2130 */
2131 err = nilfs_segctor_wait(sci);
2132 if (err)
2133 goto failed_to_write;
2134 }
2135 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2136
2137 out:
2138 nilfs_segctor_drop_written_files(sci, nilfs);
2139 return err;
2140
2141 failed_to_write:
2142 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2143 nilfs_redirty_inodes(&sci->sc_dirty_files);
2144
2145 failed:
2146 if (nilfs_doing_gc())
2147 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2148 nilfs_segctor_abort_construction(sci, nilfs, err);
2149 goto out;
2150}
2151
2152/**
2153 * nilfs_segctor_start_timer - set timer of background write
2154 * @sci: nilfs_sc_info
2155 *
2156 * If the timer has already been set, it ignores the new request.
2157 * This function MUST be called within a section locking the segment
2158 * semaphore.
2159 */
2160static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2161{
2162 spin_lock(&sci->sc_state_lock);
2163 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2164 sci->sc_timer.expires = jiffies + sci->sc_interval;
2165 add_timer(&sci->sc_timer);
2166 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2167 }
2168 spin_unlock(&sci->sc_state_lock);
2169}
2170
2171static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2172{
2173 spin_lock(&sci->sc_state_lock);
2174 if (!(sci->sc_flush_request & BIT(bn))) {
2175 unsigned long prev_req = sci->sc_flush_request;
2176
2177 sci->sc_flush_request |= BIT(bn);
2178 if (!prev_req)
2179 wake_up(&sci->sc_wait_daemon);
2180 }
2181 spin_unlock(&sci->sc_state_lock);
2182}
2183
2184/**
2185 * nilfs_flush_segment - trigger a segment construction for resource control
2186 * @sb: super block
2187 * @ino: inode number of the file to be flushed out.
2188 */
2189void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2190{
2191 struct the_nilfs *nilfs = sb->s_fs_info;
2192 struct nilfs_sc_info *sci = nilfs->ns_writer;
2193
2194 if (!sci || nilfs_doing_construction())
2195 return;
2196 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2197 /* assign bit 0 to data files */
2198}
2199
2200struct nilfs_segctor_wait_request {
2201 wait_queue_entry_t wq;
2202 __u32 seq;
2203 int err;
2204 atomic_t done;
2205};
2206
2207static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2208{
2209 struct nilfs_segctor_wait_request wait_req;
2210 int err = 0;
2211
2212 spin_lock(&sci->sc_state_lock);
2213 init_wait(&wait_req.wq);
2214 wait_req.err = 0;
2215 atomic_set(&wait_req.done, 0);
2216 wait_req.seq = ++sci->sc_seq_request;
2217 spin_unlock(&sci->sc_state_lock);
2218
2219 init_waitqueue_entry(&wait_req.wq, current);
2220 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2221 set_current_state(TASK_INTERRUPTIBLE);
2222 wake_up(&sci->sc_wait_daemon);
2223
2224 for (;;) {
2225 if (atomic_read(&wait_req.done)) {
2226 err = wait_req.err;
2227 break;
2228 }
2229 if (!signal_pending(current)) {
2230 schedule();
2231 continue;
2232 }
2233 err = -ERESTARTSYS;
2234 break;
2235 }
2236 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2237 return err;
2238}
2239
2240static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2241{
2242 struct nilfs_segctor_wait_request *wrq, *n;
2243 unsigned long flags;
2244
2245 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2246 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
2247 if (!atomic_read(&wrq->done) &&
2248 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2249 wrq->err = err;
2250 atomic_set(&wrq->done, 1);
2251 }
2252 if (atomic_read(&wrq->done)) {
2253 wrq->wq.func(&wrq->wq,
2254 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2255 0, NULL);
2256 }
2257 }
2258 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2259}
2260
2261/**
2262 * nilfs_construct_segment - construct a logical segment
2263 * @sb: super block
2264 *
2265 * Return Value: On success, 0 is returned. On errors, one of the following
2266 * negative error code is returned.
2267 *
2268 * %-EROFS - Read only filesystem.
2269 *
2270 * %-EIO - I/O error
2271 *
2272 * %-ENOSPC - No space left on device (only in a panic state).
2273 *
2274 * %-ERESTARTSYS - Interrupted.
2275 *
2276 * %-ENOMEM - Insufficient memory available.
2277 */
2278int nilfs_construct_segment(struct super_block *sb)
2279{
2280 struct the_nilfs *nilfs = sb->s_fs_info;
2281 struct nilfs_sc_info *sci = nilfs->ns_writer;
2282 struct nilfs_transaction_info *ti;
2283
2284 if (sb_rdonly(sb) || unlikely(!sci))
2285 return -EROFS;
2286
2287 /* A call inside transactions causes a deadlock. */
2288 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2289
2290 return nilfs_segctor_sync(sci);
2291}
2292
2293/**
2294 * nilfs_construct_dsync_segment - construct a data-only logical segment
2295 * @sb: super block
2296 * @inode: inode whose data blocks should be written out
2297 * @start: start byte offset
2298 * @end: end byte offset (inclusive)
2299 *
2300 * Return Value: On success, 0 is returned. On errors, one of the following
2301 * negative error code is returned.
2302 *
2303 * %-EROFS - Read only filesystem.
2304 *
2305 * %-EIO - I/O error
2306 *
2307 * %-ENOSPC - No space left on device (only in a panic state).
2308 *
2309 * %-ERESTARTSYS - Interrupted.
2310 *
2311 * %-ENOMEM - Insufficient memory available.
2312 */
2313int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2314 loff_t start, loff_t end)
2315{
2316 struct the_nilfs *nilfs = sb->s_fs_info;
2317 struct nilfs_sc_info *sci = nilfs->ns_writer;
2318 struct nilfs_inode_info *ii;
2319 struct nilfs_transaction_info ti;
2320 int err = 0;
2321
2322 if (sb_rdonly(sb) || unlikely(!sci))
2323 return -EROFS;
2324
2325 nilfs_transaction_lock(sb, &ti, 0);
2326
2327 ii = NILFS_I(inode);
2328 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2329 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2330 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2331 nilfs_discontinued(nilfs)) {
2332 nilfs_transaction_unlock(sb);
2333 err = nilfs_segctor_sync(sci);
2334 return err;
2335 }
2336
2337 spin_lock(&nilfs->ns_inode_lock);
2338 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2339 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2340 spin_unlock(&nilfs->ns_inode_lock);
2341 nilfs_transaction_unlock(sb);
2342 return 0;
2343 }
2344 spin_unlock(&nilfs->ns_inode_lock);
2345 sci->sc_dsync_inode = ii;
2346 sci->sc_dsync_start = start;
2347 sci->sc_dsync_end = end;
2348
2349 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2350 if (!err)
2351 nilfs->ns_flushed_device = 0;
2352
2353 nilfs_transaction_unlock(sb);
2354 return err;
2355}
2356
2357#define FLUSH_FILE_BIT (0x1) /* data file only */
2358#define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2359
2360/**
2361 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2362 * @sci: segment constructor object
2363 */
2364static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2365{
2366 spin_lock(&sci->sc_state_lock);
2367 sci->sc_seq_accepted = sci->sc_seq_request;
2368 spin_unlock(&sci->sc_state_lock);
2369 del_timer_sync(&sci->sc_timer);
2370}
2371
2372/**
2373 * nilfs_segctor_notify - notify the result of request to caller threads
2374 * @sci: segment constructor object
2375 * @mode: mode of log forming
2376 * @err: error code to be notified
2377 */
2378static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2379{
2380 /* Clear requests (even when the construction failed) */
2381 spin_lock(&sci->sc_state_lock);
2382
2383 if (mode == SC_LSEG_SR) {
2384 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2385 sci->sc_seq_done = sci->sc_seq_accepted;
2386 nilfs_segctor_wakeup(sci, err);
2387 sci->sc_flush_request = 0;
2388 } else {
2389 if (mode == SC_FLUSH_FILE)
2390 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2391 else if (mode == SC_FLUSH_DAT)
2392 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2393
2394 /* re-enable timer if checkpoint creation was not done */
2395 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2396 time_before(jiffies, sci->sc_timer.expires))
2397 add_timer(&sci->sc_timer);
2398 }
2399 spin_unlock(&sci->sc_state_lock);
2400}
2401
2402/**
2403 * nilfs_segctor_construct - form logs and write them to disk
2404 * @sci: segment constructor object
2405 * @mode: mode of log forming
2406 */
2407static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2408{
2409 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2410 struct nilfs_super_block **sbp;
2411 int err = 0;
2412
2413 nilfs_segctor_accept(sci);
2414
2415 if (nilfs_discontinued(nilfs))
2416 mode = SC_LSEG_SR;
2417 if (!nilfs_segctor_confirm(sci))
2418 err = nilfs_segctor_do_construct(sci, mode);
2419
2420 if (likely(!err)) {
2421 if (mode != SC_FLUSH_DAT)
2422 atomic_set(&nilfs->ns_ndirtyblks, 0);
2423 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2424 nilfs_discontinued(nilfs)) {
2425 down_write(&nilfs->ns_sem);
2426 err = -EIO;
2427 sbp = nilfs_prepare_super(sci->sc_super,
2428 nilfs_sb_will_flip(nilfs));
2429 if (likely(sbp)) {
2430 nilfs_set_log_cursor(sbp[0], nilfs);
2431 err = nilfs_commit_super(sci->sc_super,
2432 NILFS_SB_COMMIT);
2433 }
2434 up_write(&nilfs->ns_sem);
2435 }
2436 }
2437
2438 nilfs_segctor_notify(sci, mode, err);
2439 return err;
2440}
2441
2442static void nilfs_construction_timeout(struct timer_list *t)
2443{
2444 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2445
2446 wake_up_process(sci->sc_timer_task);
2447}
2448
2449static void
2450nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2451{
2452 struct nilfs_inode_info *ii, *n;
2453
2454 list_for_each_entry_safe(ii, n, head, i_dirty) {
2455 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2456 continue;
2457 list_del_init(&ii->i_dirty);
2458 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2459 nilfs_btnode_cache_clear(ii->i_assoc_inode->i_mapping);
2460 iput(&ii->vfs_inode);
2461 }
2462}
2463
2464int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2465 void **kbufs)
2466{
2467 struct the_nilfs *nilfs = sb->s_fs_info;
2468 struct nilfs_sc_info *sci = nilfs->ns_writer;
2469 struct nilfs_transaction_info ti;
2470 int err;
2471
2472 if (unlikely(!sci))
2473 return -EROFS;
2474
2475 nilfs_transaction_lock(sb, &ti, 1);
2476
2477 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2478 if (unlikely(err))
2479 goto out_unlock;
2480
2481 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2482 if (unlikely(err)) {
2483 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2484 goto out_unlock;
2485 }
2486
2487 sci->sc_freesegs = kbufs[4];
2488 sci->sc_nfreesegs = argv[4].v_nmembs;
2489 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2490
2491 for (;;) {
2492 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2493 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2494
2495 if (likely(!err))
2496 break;
2497
2498 nilfs_warn(sb, "error %d cleaning segments", err);
2499 set_current_state(TASK_INTERRUPTIBLE);
2500 schedule_timeout(sci->sc_interval);
2501 }
2502 if (nilfs_test_opt(nilfs, DISCARD)) {
2503 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2504 sci->sc_nfreesegs);
2505 if (ret) {
2506 nilfs_warn(sb,
2507 "error %d on discard request, turning discards off for the device",
2508 ret);
2509 nilfs_clear_opt(nilfs, DISCARD);
2510 }
2511 }
2512
2513 out_unlock:
2514 sci->sc_freesegs = NULL;
2515 sci->sc_nfreesegs = 0;
2516 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2517 nilfs_transaction_unlock(sb);
2518 return err;
2519}
2520
2521static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2522{
2523 struct nilfs_transaction_info ti;
2524
2525 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2526 nilfs_segctor_construct(sci, mode);
2527
2528 /*
2529 * Unclosed segment should be retried. We do this using sc_timer.
2530 * Timeout of sc_timer will invoke complete construction which leads
2531 * to close the current logical segment.
2532 */
2533 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2534 nilfs_segctor_start_timer(sci);
2535
2536 nilfs_transaction_unlock(sci->sc_super);
2537}
2538
2539static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2540{
2541 int mode = 0;
2542
2543 spin_lock(&sci->sc_state_lock);
2544 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2545 SC_FLUSH_DAT : SC_FLUSH_FILE;
2546 spin_unlock(&sci->sc_state_lock);
2547
2548 if (mode) {
2549 nilfs_segctor_do_construct(sci, mode);
2550
2551 spin_lock(&sci->sc_state_lock);
2552 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2553 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2554 spin_unlock(&sci->sc_state_lock);
2555 }
2556 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2557}
2558
2559static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2560{
2561 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2562 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2563 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2564 return SC_FLUSH_FILE;
2565 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2566 return SC_FLUSH_DAT;
2567 }
2568 return SC_LSEG_SR;
2569}
2570
2571/**
2572 * nilfs_segctor_thread - main loop of the segment constructor thread.
2573 * @arg: pointer to a struct nilfs_sc_info.
2574 *
2575 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2576 * to execute segment constructions.
2577 */
2578static int nilfs_segctor_thread(void *arg)
2579{
2580 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2581 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2582 int timeout = 0;
2583
2584 sci->sc_timer_task = current;
2585
2586 /* start sync. */
2587 sci->sc_task = current;
2588 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2589 nilfs_info(sci->sc_super,
2590 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
2591 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2592
2593 set_freezable();
2594 spin_lock(&sci->sc_state_lock);
2595 loop:
2596 for (;;) {
2597 int mode;
2598
2599 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2600 goto end_thread;
2601
2602 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2603 mode = SC_LSEG_SR;
2604 else if (sci->sc_flush_request)
2605 mode = nilfs_segctor_flush_mode(sci);
2606 else
2607 break;
2608
2609 spin_unlock(&sci->sc_state_lock);
2610 nilfs_segctor_thread_construct(sci, mode);
2611 spin_lock(&sci->sc_state_lock);
2612 timeout = 0;
2613 }
2614
2615
2616 if (freezing(current)) {
2617 spin_unlock(&sci->sc_state_lock);
2618 try_to_freeze();
2619 spin_lock(&sci->sc_state_lock);
2620 } else {
2621 DEFINE_WAIT(wait);
2622 int should_sleep = 1;
2623
2624 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2625 TASK_INTERRUPTIBLE);
2626
2627 if (sci->sc_seq_request != sci->sc_seq_done)
2628 should_sleep = 0;
2629 else if (sci->sc_flush_request)
2630 should_sleep = 0;
2631 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2632 should_sleep = time_before(jiffies,
2633 sci->sc_timer.expires);
2634
2635 if (should_sleep) {
2636 spin_unlock(&sci->sc_state_lock);
2637 schedule();
2638 spin_lock(&sci->sc_state_lock);
2639 }
2640 finish_wait(&sci->sc_wait_daemon, &wait);
2641 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2642 time_after_eq(jiffies, sci->sc_timer.expires));
2643
2644 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2645 set_nilfs_discontinued(nilfs);
2646 }
2647 goto loop;
2648
2649 end_thread:
2650 /* end sync. */
2651 sci->sc_task = NULL;
2652 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2653 spin_unlock(&sci->sc_state_lock);
2654 return 0;
2655}
2656
2657static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2658{
2659 struct task_struct *t;
2660
2661 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2662 if (IS_ERR(t)) {
2663 int err = PTR_ERR(t);
2664
2665 nilfs_err(sci->sc_super, "error %d creating segctord thread",
2666 err);
2667 return err;
2668 }
2669 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2670 return 0;
2671}
2672
2673static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2674 __acquires(&sci->sc_state_lock)
2675 __releases(&sci->sc_state_lock)
2676{
2677 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2678
2679 while (sci->sc_task) {
2680 wake_up(&sci->sc_wait_daemon);
2681 spin_unlock(&sci->sc_state_lock);
2682 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2683 spin_lock(&sci->sc_state_lock);
2684 }
2685}
2686
2687/*
2688 * Setup & clean-up functions
2689 */
2690static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2691 struct nilfs_root *root)
2692{
2693 struct the_nilfs *nilfs = sb->s_fs_info;
2694 struct nilfs_sc_info *sci;
2695
2696 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2697 if (!sci)
2698 return NULL;
2699
2700 sci->sc_super = sb;
2701
2702 nilfs_get_root(root);
2703 sci->sc_root = root;
2704
2705 init_waitqueue_head(&sci->sc_wait_request);
2706 init_waitqueue_head(&sci->sc_wait_daemon);
2707 init_waitqueue_head(&sci->sc_wait_task);
2708 spin_lock_init(&sci->sc_state_lock);
2709 INIT_LIST_HEAD(&sci->sc_dirty_files);
2710 INIT_LIST_HEAD(&sci->sc_segbufs);
2711 INIT_LIST_HEAD(&sci->sc_write_logs);
2712 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2713 INIT_LIST_HEAD(&sci->sc_iput_queue);
2714 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2715 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
2716
2717 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2718 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2719 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2720
2721 if (nilfs->ns_interval)
2722 sci->sc_interval = HZ * nilfs->ns_interval;
2723 if (nilfs->ns_watermark)
2724 sci->sc_watermark = nilfs->ns_watermark;
2725 return sci;
2726}
2727
2728static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2729{
2730 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2731
2732 /*
2733 * The segctord thread was stopped and its timer was removed.
2734 * But some tasks remain.
2735 */
2736 do {
2737 struct nilfs_transaction_info ti;
2738
2739 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2740 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2741 nilfs_transaction_unlock(sci->sc_super);
2742
2743 flush_work(&sci->sc_iput_work);
2744
2745 } while (ret && ret != -EROFS && retrycount-- > 0);
2746}
2747
2748/**
2749 * nilfs_segctor_destroy - destroy the segment constructor.
2750 * @sci: nilfs_sc_info
2751 *
2752 * nilfs_segctor_destroy() kills the segctord thread and frees
2753 * the nilfs_sc_info struct.
2754 * Caller must hold the segment semaphore.
2755 */
2756static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2757{
2758 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2759 int flag;
2760
2761 up_write(&nilfs->ns_segctor_sem);
2762
2763 spin_lock(&sci->sc_state_lock);
2764 nilfs_segctor_kill_thread(sci);
2765 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2766 || sci->sc_seq_request != sci->sc_seq_done);
2767 spin_unlock(&sci->sc_state_lock);
2768
2769 if (flush_work(&sci->sc_iput_work))
2770 flag = true;
2771
2772 if (flag || !nilfs_segctor_confirm(sci))
2773 nilfs_segctor_write_out(sci);
2774
2775 if (!list_empty(&sci->sc_dirty_files)) {
2776 nilfs_warn(sci->sc_super,
2777 "disposed unprocessed dirty file(s) when stopping log writer");
2778 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2779 }
2780
2781 if (!list_empty(&sci->sc_iput_queue)) {
2782 nilfs_warn(sci->sc_super,
2783 "disposed unprocessed inode(s) in iput queue when stopping log writer");
2784 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2785 }
2786
2787 WARN_ON(!list_empty(&sci->sc_segbufs));
2788 WARN_ON(!list_empty(&sci->sc_write_logs));
2789
2790 nilfs_put_root(sci->sc_root);
2791
2792 down_write(&nilfs->ns_segctor_sem);
2793
2794 timer_shutdown_sync(&sci->sc_timer);
2795 kfree(sci);
2796}
2797
2798/**
2799 * nilfs_attach_log_writer - attach log writer
2800 * @sb: super block instance
2801 * @root: root object of the current filesystem tree
2802 *
2803 * This allocates a log writer object, initializes it, and starts the
2804 * log writer.
2805 *
2806 * Return Value: On success, 0 is returned. On error, one of the following
2807 * negative error code is returned.
2808 *
2809 * %-ENOMEM - Insufficient memory available.
2810 */
2811int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2812{
2813 struct the_nilfs *nilfs = sb->s_fs_info;
2814 int err;
2815
2816 if (nilfs->ns_writer) {
2817 /*
2818 * This happens if the filesystem is made read-only by
2819 * __nilfs_error or nilfs_remount and then remounted
2820 * read/write. In these cases, reuse the existing
2821 * writer.
2822 */
2823 return 0;
2824 }
2825
2826 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2827 if (!nilfs->ns_writer)
2828 return -ENOMEM;
2829
2830 inode_attach_wb(nilfs->ns_bdev->bd_inode, NULL);
2831
2832 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2833 if (unlikely(err))
2834 nilfs_detach_log_writer(sb);
2835
2836 return err;
2837}
2838
2839/**
2840 * nilfs_detach_log_writer - destroy log writer
2841 * @sb: super block instance
2842 *
2843 * This kills log writer daemon, frees the log writer object, and
2844 * destroys list of dirty files.
2845 */
2846void nilfs_detach_log_writer(struct super_block *sb)
2847{
2848 struct the_nilfs *nilfs = sb->s_fs_info;
2849 LIST_HEAD(garbage_list);
2850
2851 down_write(&nilfs->ns_segctor_sem);
2852 if (nilfs->ns_writer) {
2853 nilfs_segctor_destroy(nilfs->ns_writer);
2854 nilfs->ns_writer = NULL;
2855 }
2856 set_nilfs_purging(nilfs);
2857
2858 /* Force to free the list of dirty files */
2859 spin_lock(&nilfs->ns_inode_lock);
2860 if (!list_empty(&nilfs->ns_dirty_files)) {
2861 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2862 nilfs_warn(sb,
2863 "disposed unprocessed dirty file(s) when detaching log writer");
2864 }
2865 spin_unlock(&nilfs->ns_inode_lock);
2866 up_write(&nilfs->ns_segctor_sem);
2867
2868 nilfs_dispose_list(nilfs, &garbage_list, 1);
2869 clear_nilfs_purging(nilfs);
2870}