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Linux 6.13-rc4
[linux.git] / fs / nilfs2 / segment.c
blob58725183089733e5955486dfe981cfa20ff15b6d
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 */
47 enum {
48 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
49 SC_LSEG_DSYNC, /*
50 * Flush data blocks of a given file and make
51 * a logical segment without a super root.
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 */
64 enum {
65 NILFS_ST_INIT = 0,
66 NILFS_ST_GC, /* Collecting dirty blocks for GC */
67 NILFS_ST_FILE,
68 NILFS_ST_IFILE,
69 NILFS_ST_CPFILE,
70 NILFS_ST_SUFILE,
71 NILFS_ST_DAT,
72 NILFS_ST_SR, /* Super root */
73 NILFS_ST_DSYNC, /* Data sync blocks */
74 NILFS_ST_DONE,
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 */
90 static 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
96 static 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
102 static 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 */
114 struct nilfs_sc_operations {
115 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
116 struct inode *);
117 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
118 struct inode *);
119 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
120 struct inode *);
121 void (*write_data_binfo)(struct nilfs_sc_info *,
122 struct nilfs_segsum_pointer *,
123 union nilfs_binfo *);
124 void (*write_node_binfo)(struct nilfs_sc_info *,
125 struct nilfs_segsum_pointer *,
126 union nilfs_binfo *);
127 };
128
129 /*
130 * Other definitions
131 */
132 static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
133 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
134 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
135 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
136
137 #define nilfs_cnt32_ge(a, b) \
138 (typecheck(__u32, a) && typecheck(__u32, b) && \
139 ((__s32)((a) - (b)) >= 0))
140
141 static 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 */
201 int 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 */
256 int 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
292 void 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
315 void 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
338 static 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
373 static 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
388 static 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 */
411 static 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 */
440 static 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
450 static 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
463 static 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 */
483 static 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
495 static 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
509 static 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 (ii->i_type & NILFS_I_TYPE_GC)
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
543 static 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 */
582 static 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
598 static 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
605 static 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
613 static 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
622 static 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
631 static 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
639 static 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
654 static 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
662 static 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
671 static 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
680 static 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
688 static 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
696 static 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
758 static 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
791 static 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
824 static 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
833 static 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
849 static 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
857 static 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
873 static 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
883 static void nilfs_fill_in_file_bmap(struct inode *ifile,
884 struct nilfs_inode_info *ii)
885
886 {
887 struct buffer_head *ibh;
888 struct nilfs_inode *raw_inode;
889
890 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
891 ibh = ii->i_bh;
892 BUG_ON(!ibh);
893 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
894 ibh);
895 nilfs_bmap_write(ii->i_bmap, raw_inode);
896 nilfs_ifile_unmap_inode(raw_inode);
897 }
898 }
899
900 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
901 {
902 struct nilfs_inode_info *ii;
903
904 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
905 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
906 set_bit(NILFS_I_COLLECTED, &ii->i_state);
907 }
908 }
909
910 /**
911 * nilfs_write_root_mdt_inode - export root metadata inode information to
912 * the on-disk inode
913 * @inode: inode object of the root metadata file
914 * @raw_inode: on-disk inode
915 *
916 * nilfs_write_root_mdt_inode() writes inode information and bmap data of
917 * @inode to the inode area of the metadata file allocated on the super root
918 * block created to finalize the log. Since super root blocks are configured
919 * each time, this function zero-fills the unused area of @raw_inode.
920 */
921 static void nilfs_write_root_mdt_inode(struct inode *inode,
922 struct nilfs_inode *raw_inode)
923 {
924 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
925
926 nilfs_write_inode_common(inode, raw_inode);
927
928 /* zero-fill unused portion of raw_inode */
929 raw_inode->i_xattr = 0;
930 raw_inode->i_pad = 0;
931 memset((void *)raw_inode + sizeof(*raw_inode), 0,
932 nilfs->ns_inode_size - sizeof(*raw_inode));
933
934 nilfs_bmap_write(NILFS_I(inode)->i_bmap, raw_inode);
935 }
936
937 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
938 struct the_nilfs *nilfs)
939 {
940 struct buffer_head *bh_sr;
941 struct nilfs_super_root *raw_sr;
942 unsigned int isz, srsz;
943
944 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
945
946 lock_buffer(bh_sr);
947 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
948 isz = nilfs->ns_inode_size;
949 srsz = NILFS_SR_BYTES(isz);
950
951 raw_sr->sr_sum = 0; /* Ensure initialization within this update */
952 raw_sr->sr_bytes = cpu_to_le16(srsz);
953 raw_sr->sr_nongc_ctime
954 = cpu_to_le64(nilfs_doing_gc() ?
955 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
956 raw_sr->sr_flags = 0;
957
958 nilfs_write_root_mdt_inode(nilfs->ns_dat, (void *)raw_sr +
959 NILFS_SR_DAT_OFFSET(isz));
960 nilfs_write_root_mdt_inode(nilfs->ns_cpfile, (void *)raw_sr +
961 NILFS_SR_CPFILE_OFFSET(isz));
962 nilfs_write_root_mdt_inode(nilfs->ns_sufile, (void *)raw_sr +
963 NILFS_SR_SUFILE_OFFSET(isz));
964
965 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
966 set_buffer_uptodate(bh_sr);
967 unlock_buffer(bh_sr);
968 }
969
970 static void nilfs_redirty_inodes(struct list_head *head)
971 {
972 struct nilfs_inode_info *ii;
973
974 list_for_each_entry(ii, head, i_dirty) {
975 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
976 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
977 }
978 }
979
980 static void nilfs_drop_collected_inodes(struct list_head *head)
981 {
982 struct nilfs_inode_info *ii;
983
984 list_for_each_entry(ii, head, i_dirty) {
985 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
986 continue;
987
988 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
989 set_bit(NILFS_I_UPDATED, &ii->i_state);
990 }
991 }
992
993 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
994 struct inode *inode,
995 struct list_head *listp,
996 int (*collect)(struct nilfs_sc_info *,
997 struct buffer_head *,
998 struct inode *))
999 {
1000 struct buffer_head *bh, *n;
1001 int err = 0;
1002
1003 if (collect) {
1004 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1005 list_del_init(&bh->b_assoc_buffers);
1006 err = collect(sci, bh, inode);
1007 brelse(bh);
1008 if (unlikely(err))
1009 goto dispose_buffers;
1010 }
1011 return 0;
1012 }
1013
1014 dispose_buffers:
1015 while (!list_empty(listp)) {
1016 bh = list_first_entry(listp, struct buffer_head,
1017 b_assoc_buffers);
1018 list_del_init(&bh->b_assoc_buffers);
1019 brelse(bh);
1020 }
1021 return err;
1022 }
1023
1024 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1025 {
1026 /* Remaining number of blocks within segment buffer */
1027 return sci->sc_segbuf_nblocks -
1028 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1029 }
1030
1031 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1032 struct inode *inode,
1033 const struct nilfs_sc_operations *sc_ops)
1034 {
1035 LIST_HEAD(data_buffers);
1036 LIST_HEAD(node_buffers);
1037 int err;
1038
1039 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1040 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1041
1042 n = nilfs_lookup_dirty_data_buffers(
1043 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1044 if (n > rest) {
1045 err = nilfs_segctor_apply_buffers(
1046 sci, inode, &data_buffers,
1047 sc_ops->collect_data);
1048 BUG_ON(!err); /* always receive -E2BIG or true error */
1049 goto break_or_fail;
1050 }
1051 }
1052 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1053
1054 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1055 err = nilfs_segctor_apply_buffers(
1056 sci, inode, &data_buffers, sc_ops->collect_data);
1057 if (unlikely(err)) {
1058 /* dispose node list */
1059 nilfs_segctor_apply_buffers(
1060 sci, inode, &node_buffers, NULL);
1061 goto break_or_fail;
1062 }
1063 sci->sc_stage.flags |= NILFS_CF_NODE;
1064 }
1065 /* Collect node */
1066 err = nilfs_segctor_apply_buffers(
1067 sci, inode, &node_buffers, sc_ops->collect_node);
1068 if (unlikely(err))
1069 goto break_or_fail;
1070
1071 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1072 err = nilfs_segctor_apply_buffers(
1073 sci, inode, &node_buffers, sc_ops->collect_bmap);
1074 if (unlikely(err))
1075 goto break_or_fail;
1076
1077 nilfs_segctor_end_finfo(sci, inode);
1078 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1079
1080 break_or_fail:
1081 return err;
1082 }
1083
1084 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1085 struct inode *inode)
1086 {
1087 LIST_HEAD(data_buffers);
1088 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1089 int err;
1090
1091 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1092 sci->sc_dsync_start,
1093 sci->sc_dsync_end);
1094
1095 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1096 nilfs_collect_file_data);
1097 if (!err) {
1098 nilfs_segctor_end_finfo(sci, inode);
1099 BUG_ON(n > rest);
1100 /* always receive -E2BIG or true error if n > rest */
1101 }
1102 return err;
1103 }
1104
1105 /**
1106 * nilfs_free_segments - free the segments given by an array of segment numbers
1107 * @nilfs: nilfs object
1108 * @segnumv: array of segment numbers to be freed
1109 * @nsegs: number of segments to be freed in @segnumv
1110 *
1111 * nilfs_free_segments() wraps nilfs_sufile_freev() and
1112 * nilfs_sufile_cancel_freev(), and edits the segment usage metadata file
1113 * (sufile) to free all segments given by @segnumv and @nsegs at once. If
1114 * it fails midway, it cancels the changes so that none of the segments are
1115 * freed. If @nsegs is 0, this function does nothing.
1116 *
1117 * The freeing of segments is not finalized until the writing of a log with
1118 * a super root block containing this sufile change is complete, and it can
1119 * be canceled with nilfs_sufile_cancel_freev() until then.
1120 *
1121 * Return: 0 on success, or the following negative error code on failure.
1122 * * %-EINVAL - Invalid segment number.
1123 * * %-EIO - I/O error (including metadata corruption).
1124 * * %-ENOMEM - Insufficient memory available.
1125 */
1126 static int nilfs_free_segments(struct the_nilfs *nilfs, __u64 *segnumv,
1127 size_t nsegs)
1128 {
1129 size_t ndone;
1130 int ret;
1131
1132 if (!nsegs)
1133 return 0;
1134
1135 ret = nilfs_sufile_freev(nilfs->ns_sufile, segnumv, nsegs, &ndone);
1136 if (unlikely(ret)) {
1137 nilfs_sufile_cancel_freev(nilfs->ns_sufile, segnumv, ndone,
1138 NULL);
1139 /*
1140 * If a segment usage of the segments to be freed is in a
1141 * hole block, nilfs_sufile_freev() will return -ENOENT.
1142 * In this case, -EINVAL should be returned to the caller
1143 * since there is something wrong with the given segment
1144 * number array. This error can only occur during GC, so
1145 * there is no need to worry about it propagating to other
1146 * callers (such as fsync).
1147 */
1148 if (ret == -ENOENT) {
1149 nilfs_err(nilfs->ns_sb,
1150 "The segment usage entry %llu to be freed is invalid (in a hole)",
1151 (unsigned long long)segnumv[ndone]);
1152 ret = -EINVAL;
1153 }
1154 }
1155 return ret;
1156 }
1157
1158 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1159 {
1160 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1161 struct list_head *head;
1162 struct nilfs_inode_info *ii;
1163 int err = 0;
1164
1165 switch (nilfs_sc_cstage_get(sci)) {
1166 case NILFS_ST_INIT:
1167 /* Pre-processes */
1168 sci->sc_stage.flags = 0;
1169
1170 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1171 sci->sc_nblk_inc = 0;
1172 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1173 if (mode == SC_LSEG_DSYNC) {
1174 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1175 goto dsync_mode;
1176 }
1177 }
1178
1179 sci->sc_stage.dirty_file_ptr = NULL;
1180 sci->sc_stage.gc_inode_ptr = NULL;
1181 if (mode == SC_FLUSH_DAT) {
1182 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1183 goto dat_stage;
1184 }
1185 nilfs_sc_cstage_inc(sci);
1186 fallthrough;
1187 case NILFS_ST_GC:
1188 if (nilfs_doing_gc()) {
1189 head = &sci->sc_gc_inodes;
1190 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1191 head, i_dirty);
1192 list_for_each_entry_continue(ii, head, i_dirty) {
1193 err = nilfs_segctor_scan_file(
1194 sci, &ii->vfs_inode,
1195 &nilfs_sc_file_ops);
1196 if (unlikely(err)) {
1197 sci->sc_stage.gc_inode_ptr = list_entry(
1198 ii->i_dirty.prev,
1199 struct nilfs_inode_info,
1200 i_dirty);
1201 goto break_or_fail;
1202 }
1203 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1204 }
1205 sci->sc_stage.gc_inode_ptr = NULL;
1206 }
1207 nilfs_sc_cstage_inc(sci);
1208 fallthrough;
1209 case NILFS_ST_FILE:
1210 head = &sci->sc_dirty_files;
1211 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1212 i_dirty);
1213 list_for_each_entry_continue(ii, head, i_dirty) {
1214 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1215
1216 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1217 &nilfs_sc_file_ops);
1218 if (unlikely(err)) {
1219 sci->sc_stage.dirty_file_ptr =
1220 list_entry(ii->i_dirty.prev,
1221 struct nilfs_inode_info,
1222 i_dirty);
1223 goto break_or_fail;
1224 }
1225 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1226 /* XXX: required ? */
1227 }
1228 sci->sc_stage.dirty_file_ptr = NULL;
1229 if (mode == SC_FLUSH_FILE) {
1230 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1231 return 0;
1232 }
1233 nilfs_sc_cstage_inc(sci);
1234 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1235 fallthrough;
1236 case NILFS_ST_IFILE:
1237 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1238 &nilfs_sc_file_ops);
1239 if (unlikely(err))
1240 break;
1241 nilfs_sc_cstage_inc(sci);
1242 /* Creating a checkpoint */
1243 err = nilfs_cpfile_create_checkpoint(nilfs->ns_cpfile,
1244 nilfs->ns_cno);
1245 if (unlikely(err))
1246 break;
1247 fallthrough;
1248 case NILFS_ST_CPFILE:
1249 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1250 &nilfs_sc_file_ops);
1251 if (unlikely(err))
1252 break;
1253 nilfs_sc_cstage_inc(sci);
1254 fallthrough;
1255 case NILFS_ST_SUFILE:
1256 err = nilfs_free_segments(nilfs, sci->sc_freesegs,
1257 sci->sc_nfreesegs);
1258 if (unlikely(err))
1259 break;
1260 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1261
1262 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1263 &nilfs_sc_file_ops);
1264 if (unlikely(err))
1265 break;
1266 nilfs_sc_cstage_inc(sci);
1267 fallthrough;
1268 case NILFS_ST_DAT:
1269 dat_stage:
1270 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1271 &nilfs_sc_dat_ops);
1272 if (unlikely(err))
1273 break;
1274 if (mode == SC_FLUSH_DAT) {
1275 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1276 return 0;
1277 }
1278 nilfs_sc_cstage_inc(sci);
1279 fallthrough;
1280 case NILFS_ST_SR:
1281 if (mode == SC_LSEG_SR) {
1282 /* Appending a super root */
1283 err = nilfs_segctor_add_super_root(sci);
1284 if (unlikely(err))
1285 break;
1286 }
1287 /* End of a logical segment */
1288 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1289 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1290 return 0;
1291 case NILFS_ST_DSYNC:
1292 dsync_mode:
1293 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1294 ii = sci->sc_dsync_inode;
1295 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1296 break;
1297
1298 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1299 if (unlikely(err))
1300 break;
1301 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1302 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1303 return 0;
1304 case NILFS_ST_DONE:
1305 return 0;
1306 default:
1307 BUG();
1308 }
1309
1310 break_or_fail:
1311 return err;
1312 }
1313
1314 /**
1315 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1316 * @sci: nilfs_sc_info
1317 * @nilfs: nilfs object
1318 */
1319 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1320 struct the_nilfs *nilfs)
1321 {
1322 struct nilfs_segment_buffer *segbuf, *prev;
1323 __u64 nextnum;
1324 int err, alloc = 0;
1325
1326 segbuf = nilfs_segbuf_new(sci->sc_super);
1327 if (unlikely(!segbuf))
1328 return -ENOMEM;
1329
1330 if (list_empty(&sci->sc_write_logs)) {
1331 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1332 nilfs->ns_pseg_offset, nilfs);
1333 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1334 nilfs_shift_to_next_segment(nilfs);
1335 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1336 }
1337
1338 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1339 nextnum = nilfs->ns_nextnum;
1340
1341 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1342 /* Start from the head of a new full segment */
1343 alloc++;
1344 } else {
1345 /* Continue logs */
1346 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1347 nilfs_segbuf_map_cont(segbuf, prev);
1348 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1349 nextnum = prev->sb_nextnum;
1350
1351 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1352 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1353 segbuf->sb_sum.seg_seq++;
1354 alloc++;
1355 }
1356 }
1357
1358 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1359 if (err)
1360 goto failed;
1361
1362 if (alloc) {
1363 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1364 if (err)
1365 goto failed;
1366 }
1367 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1368
1369 BUG_ON(!list_empty(&sci->sc_segbufs));
1370 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1371 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1372 return 0;
1373
1374 failed:
1375 nilfs_segbuf_free(segbuf);
1376 return err;
1377 }
1378
1379 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1380 struct the_nilfs *nilfs, int nadd)
1381 {
1382 struct nilfs_segment_buffer *segbuf, *prev;
1383 struct inode *sufile = nilfs->ns_sufile;
1384 __u64 nextnextnum;
1385 LIST_HEAD(list);
1386 int err, ret, i;
1387
1388 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1389 /*
1390 * Since the segment specified with nextnum might be allocated during
1391 * the previous construction, the buffer including its segusage may
1392 * not be dirty. The following call ensures that the buffer is dirty
1393 * and will pin the buffer on memory until the sufile is written.
1394 */
1395 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1396 if (unlikely(err))
1397 return err;
1398
1399 for (i = 0; i < nadd; i++) {
1400 /* extend segment info */
1401 err = -ENOMEM;
1402 segbuf = nilfs_segbuf_new(sci->sc_super);
1403 if (unlikely(!segbuf))
1404 goto failed;
1405
1406 /* map this buffer to region of segment on-disk */
1407 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1408 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1409
1410 /* allocate the next next full segment */
1411 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1412 if (unlikely(err))
1413 goto failed_segbuf;
1414
1415 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1416 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1417
1418 list_add_tail(&segbuf->sb_list, &list);
1419 prev = segbuf;
1420 }
1421 list_splice_tail(&list, &sci->sc_segbufs);
1422 return 0;
1423
1424 failed_segbuf:
1425 nilfs_segbuf_free(segbuf);
1426 failed:
1427 list_for_each_entry(segbuf, &list, sb_list) {
1428 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1429 WARN_ON(ret); /* never fails */
1430 }
1431 nilfs_destroy_logs(&list);
1432 return err;
1433 }
1434
1435 static void nilfs_free_incomplete_logs(struct list_head *logs,
1436 struct the_nilfs *nilfs)
1437 {
1438 struct nilfs_segment_buffer *segbuf, *prev;
1439 struct inode *sufile = nilfs->ns_sufile;
1440 int ret;
1441
1442 segbuf = NILFS_FIRST_SEGBUF(logs);
1443 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1444 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1445 WARN_ON(ret); /* never fails */
1446 }
1447 if (atomic_read(&segbuf->sb_err)) {
1448 /* Case 1: The first segment failed */
1449 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1450 /*
1451 * Case 1a: Partial segment appended into an existing
1452 * segment
1453 */
1454 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1455 segbuf->sb_fseg_end);
1456 else /* Case 1b: New full segment */
1457 set_nilfs_discontinued(nilfs);
1458 }
1459
1460 prev = segbuf;
1461 list_for_each_entry_continue(segbuf, logs, sb_list) {
1462 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1463 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1464 WARN_ON(ret); /* never fails */
1465 }
1466 if (atomic_read(&segbuf->sb_err) &&
1467 segbuf->sb_segnum != nilfs->ns_nextnum)
1468 /* Case 2: extended segment (!= next) failed */
1469 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1470 prev = segbuf;
1471 }
1472 }
1473
1474 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1475 struct inode *sufile)
1476 {
1477 struct nilfs_segment_buffer *segbuf;
1478 unsigned long live_blocks;
1479 int ret;
1480
1481 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1482 live_blocks = segbuf->sb_sum.nblocks +
1483 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1484 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1485 live_blocks,
1486 sci->sc_seg_ctime);
1487 WARN_ON(ret); /* always succeed because the segusage is dirty */
1488 }
1489 }
1490
1491 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1492 {
1493 struct nilfs_segment_buffer *segbuf;
1494 int ret;
1495
1496 segbuf = NILFS_FIRST_SEGBUF(logs);
1497 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1498 segbuf->sb_pseg_start -
1499 segbuf->sb_fseg_start, 0);
1500 WARN_ON(ret); /* always succeed because the segusage is dirty */
1501
1502 list_for_each_entry_continue(segbuf, logs, sb_list) {
1503 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1504 0, 0);
1505 WARN_ON(ret); /* always succeed */
1506 }
1507 }
1508
1509 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1510 struct nilfs_segment_buffer *last,
1511 struct inode *sufile)
1512 {
1513 struct nilfs_segment_buffer *segbuf = last;
1514 int ret;
1515
1516 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1517 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1518 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1519 WARN_ON(ret);
1520 }
1521 nilfs_truncate_logs(&sci->sc_segbufs, last);
1522 }
1523
1524
1525 static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1526 struct the_nilfs *nilfs, int mode)
1527 {
1528 struct nilfs_cstage prev_stage = sci->sc_stage;
1529 int err, nadd = 1;
1530
1531 /* Collection retry loop */
1532 for (;;) {
1533 sci->sc_nblk_this_inc = 0;
1534 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1535
1536 err = nilfs_segctor_reset_segment_buffer(sci);
1537 if (unlikely(err))
1538 goto failed;
1539
1540 err = nilfs_segctor_collect_blocks(sci, mode);
1541 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1542 if (!err)
1543 break;
1544
1545 if (unlikely(err != -E2BIG))
1546 goto failed;
1547
1548 /* The current segment is filled up */
1549 if (mode != SC_LSEG_SR ||
1550 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1551 break;
1552
1553 nilfs_clear_logs(&sci->sc_segbufs);
1554
1555 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1556 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1557 sci->sc_freesegs,
1558 sci->sc_nfreesegs,
1559 NULL);
1560 WARN_ON(err); /* do not happen */
1561 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1562 }
1563
1564 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1565 if (unlikely(err))
1566 return err;
1567
1568 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1569 sci->sc_stage = prev_stage;
1570 }
1571 nilfs_segctor_zeropad_segsum(sci);
1572 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1573 return 0;
1574
1575 failed:
1576 return err;
1577 }
1578
1579 static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1580 struct buffer_head *new_bh)
1581 {
1582 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1583
1584 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1585 /* The caller must release old_bh */
1586 }
1587
1588 static int
1589 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1590 struct nilfs_segment_buffer *segbuf,
1591 int mode)
1592 {
1593 struct inode *inode = NULL;
1594 sector_t blocknr;
1595 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1596 unsigned long nblocks = 0, ndatablk = 0;
1597 const struct nilfs_sc_operations *sc_op = NULL;
1598 struct nilfs_segsum_pointer ssp;
1599 struct nilfs_finfo *finfo = NULL;
1600 union nilfs_binfo binfo;
1601 struct buffer_head *bh, *bh_org;
1602 ino_t ino = 0;
1603 int err = 0;
1604
1605 if (!nfinfo)
1606 goto out;
1607
1608 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1609 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1610 ssp.offset = sizeof(struct nilfs_segment_summary);
1611
1612 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1613 if (bh == segbuf->sb_super_root)
1614 break;
1615 if (!finfo) {
1616 finfo = nilfs_segctor_map_segsum_entry(
1617 sci, &ssp, sizeof(*finfo));
1618 ino = le64_to_cpu(finfo->fi_ino);
1619 nblocks = le32_to_cpu(finfo->fi_nblocks);
1620 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1621
1622 inode = bh->b_folio->mapping->host;
1623
1624 if (mode == SC_LSEG_DSYNC)
1625 sc_op = &nilfs_sc_dsync_ops;
1626 else if (ino == NILFS_DAT_INO)
1627 sc_op = &nilfs_sc_dat_ops;
1628 else /* file blocks */
1629 sc_op = &nilfs_sc_file_ops;
1630 }
1631 bh_org = bh;
1632 get_bh(bh_org);
1633 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1634 &binfo);
1635 if (bh != bh_org)
1636 nilfs_list_replace_buffer(bh_org, bh);
1637 brelse(bh_org);
1638 if (unlikely(err))
1639 goto failed_bmap;
1640
1641 if (ndatablk > 0)
1642 sc_op->write_data_binfo(sci, &ssp, &binfo);
1643 else
1644 sc_op->write_node_binfo(sci, &ssp, &binfo);
1645
1646 blocknr++;
1647 if (--nblocks == 0) {
1648 finfo = NULL;
1649 if (--nfinfo == 0)
1650 break;
1651 } else if (ndatablk > 0)
1652 ndatablk--;
1653 }
1654 out:
1655 return 0;
1656
1657 failed_bmap:
1658 return err;
1659 }
1660
1661 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1662 {
1663 struct nilfs_segment_buffer *segbuf;
1664 int err;
1665
1666 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1667 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1668 if (unlikely(err))
1669 return err;
1670 nilfs_segbuf_fill_in_segsum(segbuf);
1671 }
1672 return 0;
1673 }
1674
1675 static void nilfs_begin_folio_io(struct folio *folio)
1676 {
1677 if (!folio || folio_test_writeback(folio))
1678 /*
1679 * For split b-tree node pages, this function may be called
1680 * twice. We ignore the 2nd or later calls by this check.
1681 */
1682 return;
1683
1684 folio_lock(folio);
1685 folio_clear_dirty_for_io(folio);
1686 folio_start_writeback(folio);
1687 folio_unlock(folio);
1688 }
1689
1690 /**
1691 * nilfs_prepare_write_logs - prepare to write logs
1692 * @logs: logs to prepare for writing
1693 * @seed: checksum seed value
1694 *
1695 * nilfs_prepare_write_logs() adds checksums and prepares the block
1696 * buffers/folios for writing logs. In order to stabilize folios of
1697 * memory-mapped file blocks by putting them in writeback state before
1698 * calculating the checksums, first prepare to write payload blocks other
1699 * than segment summary and super root blocks in which the checksums will
1700 * be embedded.
1701 */
1702 static void nilfs_prepare_write_logs(struct list_head *logs, u32 seed)
1703 {
1704 struct nilfs_segment_buffer *segbuf;
1705 struct folio *bd_folio = NULL, *fs_folio = NULL;
1706 struct buffer_head *bh;
1707
1708 /* Prepare to write payload blocks */
1709 list_for_each_entry(segbuf, logs, sb_list) {
1710 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1711 b_assoc_buffers) {
1712 if (bh == segbuf->sb_super_root)
1713 break;
1714 set_buffer_async_write(bh);
1715 if (bh->b_folio != fs_folio) {
1716 nilfs_begin_folio_io(fs_folio);
1717 fs_folio = bh->b_folio;
1718 }
1719 }
1720 }
1721 nilfs_begin_folio_io(fs_folio);
1722
1723 nilfs_add_checksums_on_logs(logs, seed);
1724
1725 /* Prepare to write segment summary blocks */
1726 list_for_each_entry(segbuf, logs, sb_list) {
1727 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1728 b_assoc_buffers) {
1729 mark_buffer_dirty(bh);
1730 if (bh->b_folio == bd_folio)
1731 continue;
1732 if (bd_folio) {
1733 folio_lock(bd_folio);
1734 folio_wait_writeback(bd_folio);
1735 folio_clear_dirty_for_io(bd_folio);
1736 folio_start_writeback(bd_folio);
1737 folio_unlock(bd_folio);
1738 }
1739 bd_folio = bh->b_folio;
1740 }
1741 }
1742
1743 /* Prepare to write super root block */
1744 bh = NILFS_LAST_SEGBUF(logs)->sb_super_root;
1745 if (bh) {
1746 mark_buffer_dirty(bh);
1747 if (bh->b_folio != bd_folio) {
1748 folio_lock(bd_folio);
1749 folio_wait_writeback(bd_folio);
1750 folio_clear_dirty_for_io(bd_folio);
1751 folio_start_writeback(bd_folio);
1752 folio_unlock(bd_folio);
1753 bd_folio = bh->b_folio;
1754 }
1755 }
1756
1757 if (bd_folio) {
1758 folio_lock(bd_folio);
1759 folio_wait_writeback(bd_folio);
1760 folio_clear_dirty_for_io(bd_folio);
1761 folio_start_writeback(bd_folio);
1762 folio_unlock(bd_folio);
1763 }
1764 }
1765
1766 static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1767 struct the_nilfs *nilfs)
1768 {
1769 int ret;
1770
1771 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1772 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1773 return ret;
1774 }
1775
1776 static void nilfs_end_folio_io(struct folio *folio, int err)
1777 {
1778 if (!folio)
1779 return;
1780
1781 if (buffer_nilfs_node(folio_buffers(folio)) &&
1782 !folio_test_writeback(folio)) {
1783 /*
1784 * For b-tree node pages, this function may be called twice
1785 * or more because they might be split in a segment.
1786 */
1787 if (folio_test_dirty(folio)) {
1788 /*
1789 * For pages holding split b-tree node buffers, dirty
1790 * flag on the buffers may be cleared discretely.
1791 * In that case, the page is once redirtied for
1792 * remaining buffers, and it must be cancelled if
1793 * all the buffers get cleaned later.
1794 */
1795 folio_lock(folio);
1796 if (nilfs_folio_buffers_clean(folio))
1797 __nilfs_clear_folio_dirty(folio);
1798 folio_unlock(folio);
1799 }
1800 return;
1801 }
1802
1803 if (err || !nilfs_folio_buffers_clean(folio))
1804 filemap_dirty_folio(folio->mapping, folio);
1805
1806 folio_end_writeback(folio);
1807 }
1808
1809 static void nilfs_abort_logs(struct list_head *logs, int err)
1810 {
1811 struct nilfs_segment_buffer *segbuf;
1812 struct folio *bd_folio = NULL, *fs_folio = NULL;
1813 struct buffer_head *bh;
1814
1815 if (list_empty(logs))
1816 return;
1817
1818 list_for_each_entry(segbuf, logs, sb_list) {
1819 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1820 b_assoc_buffers) {
1821 clear_buffer_uptodate(bh);
1822 if (bh->b_folio != bd_folio) {
1823 if (bd_folio)
1824 folio_end_writeback(bd_folio);
1825 bd_folio = bh->b_folio;
1826 }
1827 }
1828
1829 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1830 b_assoc_buffers) {
1831 if (bh == segbuf->sb_super_root) {
1832 clear_buffer_uptodate(bh);
1833 if (bh->b_folio != bd_folio) {
1834 folio_end_writeback(bd_folio);
1835 bd_folio = bh->b_folio;
1836 }
1837 break;
1838 }
1839 clear_buffer_async_write(bh);
1840 if (bh->b_folio != fs_folio) {
1841 nilfs_end_folio_io(fs_folio, err);
1842 fs_folio = bh->b_folio;
1843 }
1844 }
1845 }
1846 if (bd_folio)
1847 folio_end_writeback(bd_folio);
1848
1849 nilfs_end_folio_io(fs_folio, err);
1850 }
1851
1852 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1853 struct the_nilfs *nilfs, int err)
1854 {
1855 LIST_HEAD(logs);
1856 int ret;
1857
1858 list_splice_tail_init(&sci->sc_write_logs, &logs);
1859 ret = nilfs_wait_on_logs(&logs);
1860 nilfs_abort_logs(&logs, ret ? : err);
1861
1862 list_splice_tail_init(&sci->sc_segbufs, &logs);
1863 if (list_empty(&logs))
1864 return; /* if the first segment buffer preparation failed */
1865
1866 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1867 nilfs_free_incomplete_logs(&logs, nilfs);
1868
1869 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1870 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1871 sci->sc_freesegs,
1872 sci->sc_nfreesegs,
1873 NULL);
1874 WARN_ON(ret); /* do not happen */
1875 }
1876
1877 nilfs_destroy_logs(&logs);
1878 }
1879
1880 static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1881 struct nilfs_segment_buffer *segbuf)
1882 {
1883 nilfs->ns_segnum = segbuf->sb_segnum;
1884 nilfs->ns_nextnum = segbuf->sb_nextnum;
1885 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1886 + segbuf->sb_sum.nblocks;
1887 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1888 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1889 }
1890
1891 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1892 {
1893 struct nilfs_segment_buffer *segbuf;
1894 struct folio *bd_folio = NULL, *fs_folio = NULL;
1895 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1896 int update_sr = false;
1897
1898 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1899 struct buffer_head *bh;
1900
1901 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1902 b_assoc_buffers) {
1903 set_buffer_uptodate(bh);
1904 clear_buffer_dirty(bh);
1905 if (bh->b_folio != bd_folio) {
1906 if (bd_folio)
1907 folio_end_writeback(bd_folio);
1908 bd_folio = bh->b_folio;
1909 }
1910 }
1911 /*
1912 * We assume that the buffers which belong to the same folio
1913 * continue over the buffer list.
1914 * Under this assumption, the last BHs of folios is
1915 * identifiable by the discontinuity of bh->b_folio
1916 * (folio != fs_folio).
1917 *
1918 * For B-tree node blocks, however, this assumption is not
1919 * guaranteed. The cleanup code of B-tree node folios needs
1920 * special care.
1921 */
1922 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1923 b_assoc_buffers) {
1924 const unsigned long set_bits = BIT(BH_Uptodate);
1925 const unsigned long clear_bits =
1926 (BIT(BH_Dirty) | BIT(BH_Async_Write) |
1927 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) |
1928 BIT(BH_NILFS_Redirected));
1929
1930 if (bh == segbuf->sb_super_root) {
1931 set_buffer_uptodate(bh);
1932 clear_buffer_dirty(bh);
1933 if (bh->b_folio != bd_folio) {
1934 folio_end_writeback(bd_folio);
1935 bd_folio = bh->b_folio;
1936 }
1937 update_sr = true;
1938 break;
1939 }
1940 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1941 if (bh->b_folio != fs_folio) {
1942 nilfs_end_folio_io(fs_folio, 0);
1943 fs_folio = bh->b_folio;
1944 }
1945 }
1946
1947 if (!nilfs_segbuf_simplex(segbuf)) {
1948 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1949 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1950 sci->sc_lseg_stime = jiffies;
1951 }
1952 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1953 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1954 }
1955 }
1956 /*
1957 * Since folios may continue over multiple segment buffers,
1958 * end of the last folio must be checked outside of the loop.
1959 */
1960 if (bd_folio)
1961 folio_end_writeback(bd_folio);
1962
1963 nilfs_end_folio_io(fs_folio, 0);
1964
1965 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1966
1967 if (nilfs_doing_gc())
1968 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1969 else
1970 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1971
1972 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1973
1974 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1975 nilfs_set_next_segment(nilfs, segbuf);
1976
1977 if (update_sr) {
1978 nilfs->ns_flushed_device = 0;
1979 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1980 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1981
1982 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1983 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1984 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1985 nilfs_segctor_clear_metadata_dirty(sci);
1986 } else
1987 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1988 }
1989
1990 static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1991 {
1992 int ret;
1993
1994 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1995 if (!ret) {
1996 nilfs_segctor_complete_write(sci);
1997 nilfs_destroy_logs(&sci->sc_write_logs);
1998 }
1999 return ret;
2000 }
2001
2002 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
2003 struct the_nilfs *nilfs)
2004 {
2005 struct nilfs_inode_info *ii, *n;
2006 struct inode *ifile = sci->sc_root->ifile;
2007
2008 spin_lock(&nilfs->ns_inode_lock);
2009 retry:
2010 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
2011 if (!ii->i_bh) {
2012 struct buffer_head *ibh;
2013 int err;
2014
2015 spin_unlock(&nilfs->ns_inode_lock);
2016 err = nilfs_ifile_get_inode_block(
2017 ifile, ii->vfs_inode.i_ino, &ibh);
2018 if (unlikely(err)) {
2019 nilfs_warn(sci->sc_super,
2020 "log writer: error %d getting inode block (ino=%lu)",
2021 err, ii->vfs_inode.i_ino);
2022 return err;
2023 }
2024 spin_lock(&nilfs->ns_inode_lock);
2025 if (likely(!ii->i_bh))
2026 ii->i_bh = ibh;
2027 else
2028 brelse(ibh);
2029 goto retry;
2030 }
2031
2032 // Always redirty the buffer to avoid race condition
2033 mark_buffer_dirty(ii->i_bh);
2034 nilfs_mdt_mark_dirty(ifile);
2035
2036 clear_bit(NILFS_I_QUEUED, &ii->i_state);
2037 set_bit(NILFS_I_BUSY, &ii->i_state);
2038 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
2039 }
2040 spin_unlock(&nilfs->ns_inode_lock);
2041
2042 return 0;
2043 }
2044
2045 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
2046 struct the_nilfs *nilfs)
2047 {
2048 struct nilfs_inode_info *ii, *n;
2049 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
2050 int defer_iput = false;
2051
2052 spin_lock(&nilfs->ns_inode_lock);
2053 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2054 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
2055 test_bit(NILFS_I_DIRTY, &ii->i_state))
2056 continue;
2057
2058 clear_bit(NILFS_I_BUSY, &ii->i_state);
2059 brelse(ii->i_bh);
2060 ii->i_bh = NULL;
2061 list_del_init(&ii->i_dirty);
2062 if (!ii->vfs_inode.i_nlink || during_mount) {
2063 /*
2064 * Defer calling iput() to avoid deadlocks if
2065 * i_nlink == 0 or mount is not yet finished.
2066 */
2067 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
2068 defer_iput = true;
2069 } else {
2070 spin_unlock(&nilfs->ns_inode_lock);
2071 iput(&ii->vfs_inode);
2072 spin_lock(&nilfs->ns_inode_lock);
2073 }
2074 }
2075 spin_unlock(&nilfs->ns_inode_lock);
2076
2077 if (defer_iput)
2078 schedule_work(&sci->sc_iput_work);
2079 }
2080
2081 /*
2082 * Main procedure of segment constructor
2083 */
2084 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2085 {
2086 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2087 int err;
2088
2089 if (sb_rdonly(sci->sc_super))
2090 return -EROFS;
2091
2092 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2093 sci->sc_cno = nilfs->ns_cno;
2094
2095 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2096 if (unlikely(err))
2097 goto out;
2098
2099 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2100 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2101
2102 if (nilfs_segctor_clean(sci))
2103 goto out;
2104
2105 do {
2106 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2107
2108 err = nilfs_segctor_begin_construction(sci, nilfs);
2109 if (unlikely(err))
2110 goto failed;
2111
2112 /* Update time stamp */
2113 sci->sc_seg_ctime = ktime_get_real_seconds();
2114
2115 err = nilfs_segctor_collect(sci, nilfs, mode);
2116 if (unlikely(err))
2117 goto failed;
2118
2119 /* Avoid empty segment */
2120 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2121 nilfs_segbuf_empty(sci->sc_curseg)) {
2122 nilfs_segctor_abort_construction(sci, nilfs, 1);
2123 goto out;
2124 }
2125
2126 err = nilfs_segctor_assign(sci, mode);
2127 if (unlikely(err))
2128 goto failed;
2129
2130 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2131 nilfs_segctor_fill_in_file_bmap(sci);
2132
2133 if (mode == SC_LSEG_SR &&
2134 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2135 err = nilfs_cpfile_finalize_checkpoint(
2136 nilfs->ns_cpfile, nilfs->ns_cno, sci->sc_root,
2137 sci->sc_nblk_inc + sci->sc_nblk_this_inc,
2138 sci->sc_seg_ctime,
2139 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags));
2140 if (unlikely(err))
2141 goto failed_to_write;
2142
2143 nilfs_segctor_fill_in_super_root(sci, nilfs);
2144 }
2145 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2146
2147 /* Write partial segments */
2148 nilfs_prepare_write_logs(&sci->sc_segbufs, nilfs->ns_crc_seed);
2149
2150 err = nilfs_segctor_write(sci, nilfs);
2151 if (unlikely(err))
2152 goto failed_to_write;
2153
2154 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2155 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2156 /*
2157 * At this point, we avoid double buffering
2158 * for blocksize < pagesize because page dirty
2159 * flag is turned off during write and dirty
2160 * buffers are not properly collected for
2161 * pages crossing over segments.
2162 */
2163 err = nilfs_segctor_wait(sci);
2164 if (err)
2165 goto failed_to_write;
2166 }
2167 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2168
2169 out:
2170 nilfs_segctor_drop_written_files(sci, nilfs);
2171 return err;
2172
2173 failed_to_write:
2174 failed:
2175 if (mode == SC_LSEG_SR && nilfs_sc_cstage_get(sci) >= NILFS_ST_IFILE)
2176 nilfs_redirty_inodes(&sci->sc_dirty_files);
2177 if (nilfs_doing_gc())
2178 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2179 nilfs_segctor_abort_construction(sci, nilfs, err);
2180 goto out;
2181 }
2182
2183 /**
2184 * nilfs_segctor_start_timer - set timer of background write
2185 * @sci: nilfs_sc_info
2186 *
2187 * If the timer has already been set, it ignores the new request.
2188 * This function MUST be called within a section locking the segment
2189 * semaphore.
2190 */
2191 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2192 {
2193 spin_lock(&sci->sc_state_lock);
2194 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2195 if (sci->sc_task) {
2196 sci->sc_timer.expires = jiffies + sci->sc_interval;
2197 add_timer(&sci->sc_timer);
2198 }
2199 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2200 }
2201 spin_unlock(&sci->sc_state_lock);
2202 }
2203
2204 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2205 {
2206 spin_lock(&sci->sc_state_lock);
2207 if (!(sci->sc_flush_request & BIT(bn))) {
2208 unsigned long prev_req = sci->sc_flush_request;
2209
2210 sci->sc_flush_request |= BIT(bn);
2211 if (!prev_req)
2212 wake_up(&sci->sc_wait_daemon);
2213 }
2214 spin_unlock(&sci->sc_state_lock);
2215 }
2216
2217 /**
2218 * nilfs_flush_segment - trigger a segment construction for resource control
2219 * @sb: super block
2220 * @ino: inode number of the file to be flushed out.
2221 */
2222 void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2223 {
2224 struct the_nilfs *nilfs = sb->s_fs_info;
2225 struct nilfs_sc_info *sci = nilfs->ns_writer;
2226
2227 if (!sci || nilfs_doing_construction())
2228 return;
2229 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2230 /* assign bit 0 to data files */
2231 }
2232
2233 struct nilfs_segctor_wait_request {
2234 wait_queue_entry_t wq;
2235 __u32 seq;
2236 int err;
2237 atomic_t done;
2238 };
2239
2240 static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2241 {
2242 struct nilfs_segctor_wait_request wait_req;
2243 int err = 0;
2244
2245 init_wait(&wait_req.wq);
2246 wait_req.err = 0;
2247 atomic_set(&wait_req.done, 0);
2248 init_waitqueue_entry(&wait_req.wq, current);
2249
2250 /*
2251 * To prevent a race issue where completion notifications from the
2252 * log writer thread are missed, increment the request sequence count
2253 * "sc_seq_request" and insert a wait queue entry using the current
2254 * sequence number into the "sc_wait_request" queue at the same time
2255 * within the lock section of "sc_state_lock".
2256 */
2257 spin_lock(&sci->sc_state_lock);
2258 wait_req.seq = ++sci->sc_seq_request;
2259 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2260 spin_unlock(&sci->sc_state_lock);
2261
2262 wake_up(&sci->sc_wait_daemon);
2263
2264 for (;;) {
2265 set_current_state(TASK_INTERRUPTIBLE);
2266
2267 /*
2268 * Synchronize only while the log writer thread is alive.
2269 * Leave flushing out after the log writer thread exits to
2270 * the cleanup work in nilfs_segctor_destroy().
2271 */
2272 if (!sci->sc_task)
2273 break;
2274
2275 if (atomic_read(&wait_req.done)) {
2276 err = wait_req.err;
2277 break;
2278 }
2279 if (!signal_pending(current)) {
2280 schedule();
2281 continue;
2282 }
2283 err = -ERESTARTSYS;
2284 break;
2285 }
2286 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2287 return err;
2288 }
2289
2290 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err, bool force)
2291 {
2292 struct nilfs_segctor_wait_request *wrq, *n;
2293 unsigned long flags;
2294
2295 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2296 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
2297 if (!atomic_read(&wrq->done) &&
2298 (force || nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq))) {
2299 wrq->err = err;
2300 atomic_set(&wrq->done, 1);
2301 }
2302 if (atomic_read(&wrq->done)) {
2303 wrq->wq.func(&wrq->wq,
2304 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2305 0, NULL);
2306 }
2307 }
2308 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2309 }
2310
2311 /**
2312 * nilfs_construct_segment - construct a logical segment
2313 * @sb: super block
2314 *
2315 * Return Value: On success, 0 is returned. On errors, one of the following
2316 * negative error code is returned.
2317 *
2318 * %-EROFS - Read only filesystem.
2319 *
2320 * %-EIO - I/O error
2321 *
2322 * %-ENOSPC - No space left on device (only in a panic state).
2323 *
2324 * %-ERESTARTSYS - Interrupted.
2325 *
2326 * %-ENOMEM - Insufficient memory available.
2327 */
2328 int nilfs_construct_segment(struct super_block *sb)
2329 {
2330 struct the_nilfs *nilfs = sb->s_fs_info;
2331 struct nilfs_sc_info *sci = nilfs->ns_writer;
2332 struct nilfs_transaction_info *ti;
2333
2334 if (sb_rdonly(sb) || unlikely(!sci))
2335 return -EROFS;
2336
2337 /* A call inside transactions causes a deadlock. */
2338 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2339
2340 return nilfs_segctor_sync(sci);
2341 }
2342
2343 /**
2344 * nilfs_construct_dsync_segment - construct a data-only logical segment
2345 * @sb: super block
2346 * @inode: inode whose data blocks should be written out
2347 * @start: start byte offset
2348 * @end: end byte offset (inclusive)
2349 *
2350 * Return Value: On success, 0 is returned. On errors, one of the following
2351 * negative error code is returned.
2352 *
2353 * %-EROFS - Read only filesystem.
2354 *
2355 * %-EIO - I/O error
2356 *
2357 * %-ENOSPC - No space left on device (only in a panic state).
2358 *
2359 * %-ERESTARTSYS - Interrupted.
2360 *
2361 * %-ENOMEM - Insufficient memory available.
2362 */
2363 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2364 loff_t start, loff_t end)
2365 {
2366 struct the_nilfs *nilfs = sb->s_fs_info;
2367 struct nilfs_sc_info *sci = nilfs->ns_writer;
2368 struct nilfs_inode_info *ii;
2369 struct nilfs_transaction_info ti;
2370 int err = 0;
2371
2372 if (sb_rdonly(sb) || unlikely(!sci))
2373 return -EROFS;
2374
2375 nilfs_transaction_lock(sb, &ti, 0);
2376
2377 ii = NILFS_I(inode);
2378 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2379 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2380 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2381 nilfs_discontinued(nilfs)) {
2382 nilfs_transaction_unlock(sb);
2383 err = nilfs_segctor_sync(sci);
2384 return err;
2385 }
2386
2387 spin_lock(&nilfs->ns_inode_lock);
2388 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2389 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2390 spin_unlock(&nilfs->ns_inode_lock);
2391 nilfs_transaction_unlock(sb);
2392 return 0;
2393 }
2394 spin_unlock(&nilfs->ns_inode_lock);
2395 sci->sc_dsync_inode = ii;
2396 sci->sc_dsync_start = start;
2397 sci->sc_dsync_end = end;
2398
2399 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2400 if (!err)
2401 nilfs->ns_flushed_device = 0;
2402
2403 nilfs_transaction_unlock(sb);
2404 return err;
2405 }
2406
2407 #define FLUSH_FILE_BIT (0x1) /* data file only */
2408 #define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2409
2410 /**
2411 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2412 * @sci: segment constructor object
2413 */
2414 static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2415 {
2416 bool thread_is_alive;
2417
2418 spin_lock(&sci->sc_state_lock);
2419 sci->sc_seq_accepted = sci->sc_seq_request;
2420 thread_is_alive = (bool)sci->sc_task;
2421 spin_unlock(&sci->sc_state_lock);
2422
2423 /*
2424 * This function does not race with the log writer thread's
2425 * termination. Therefore, deleting sc_timer, which should not be
2426 * done after the log writer thread exits, can be done safely outside
2427 * the area protected by sc_state_lock.
2428 */
2429 if (thread_is_alive)
2430 del_timer_sync(&sci->sc_timer);
2431 }
2432
2433 /**
2434 * nilfs_segctor_notify - notify the result of request to caller threads
2435 * @sci: segment constructor object
2436 * @mode: mode of log forming
2437 * @err: error code to be notified
2438 */
2439 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2440 {
2441 /* Clear requests (even when the construction failed) */
2442 spin_lock(&sci->sc_state_lock);
2443
2444 if (mode == SC_LSEG_SR) {
2445 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2446 sci->sc_seq_done = sci->sc_seq_accepted;
2447 nilfs_segctor_wakeup(sci, err, false);
2448 sci->sc_flush_request = 0;
2449 } else {
2450 if (mode == SC_FLUSH_FILE)
2451 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2452 else if (mode == SC_FLUSH_DAT)
2453 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2454
2455 /* re-enable timer if checkpoint creation was not done */
2456 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && sci->sc_task &&
2457 time_before(jiffies, sci->sc_timer.expires))
2458 add_timer(&sci->sc_timer);
2459 }
2460 spin_unlock(&sci->sc_state_lock);
2461 }
2462
2463 /**
2464 * nilfs_segctor_construct - form logs and write them to disk
2465 * @sci: segment constructor object
2466 * @mode: mode of log forming
2467 */
2468 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2469 {
2470 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2471 struct nilfs_super_block **sbp;
2472 int err = 0;
2473
2474 nilfs_segctor_accept(sci);
2475
2476 if (nilfs_discontinued(nilfs))
2477 mode = SC_LSEG_SR;
2478 if (!nilfs_segctor_confirm(sci))
2479 err = nilfs_segctor_do_construct(sci, mode);
2480
2481 if (likely(!err)) {
2482 if (mode != SC_FLUSH_DAT)
2483 atomic_set(&nilfs->ns_ndirtyblks, 0);
2484 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2485 nilfs_discontinued(nilfs)) {
2486 down_write(&nilfs->ns_sem);
2487 err = -EIO;
2488 sbp = nilfs_prepare_super(sci->sc_super,
2489 nilfs_sb_will_flip(nilfs));
2490 if (likely(sbp)) {
2491 nilfs_set_log_cursor(sbp[0], nilfs);
2492 err = nilfs_commit_super(sci->sc_super,
2493 NILFS_SB_COMMIT);
2494 }
2495 up_write(&nilfs->ns_sem);
2496 }
2497 }
2498
2499 nilfs_segctor_notify(sci, mode, err);
2500 return err;
2501 }
2502
2503 static void nilfs_construction_timeout(struct timer_list *t)
2504 {
2505 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2506
2507 wake_up_process(sci->sc_task);
2508 }
2509
2510 static void
2511 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2512 {
2513 struct nilfs_inode_info *ii, *n;
2514
2515 list_for_each_entry_safe(ii, n, head, i_dirty) {
2516 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2517 continue;
2518 list_del_init(&ii->i_dirty);
2519 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2520 nilfs_btnode_cache_clear(ii->i_assoc_inode->i_mapping);
2521 iput(&ii->vfs_inode);
2522 }
2523 }
2524
2525 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2526 void **kbufs)
2527 {
2528 struct the_nilfs *nilfs = sb->s_fs_info;
2529 struct nilfs_sc_info *sci = nilfs->ns_writer;
2530 struct nilfs_transaction_info ti;
2531 int err;
2532
2533 if (unlikely(!sci))
2534 return -EROFS;
2535
2536 nilfs_transaction_lock(sb, &ti, 1);
2537
2538 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2539 if (unlikely(err))
2540 goto out_unlock;
2541
2542 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2543 if (unlikely(err)) {
2544 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2545 goto out_unlock;
2546 }
2547
2548 sci->sc_freesegs = kbufs[4];
2549 sci->sc_nfreesegs = argv[4].v_nmembs;
2550 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2551
2552 for (;;) {
2553 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2554 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2555
2556 if (likely(!err))
2557 break;
2558
2559 nilfs_warn(sb, "error %d cleaning segments", err);
2560 set_current_state(TASK_INTERRUPTIBLE);
2561 schedule_timeout(sci->sc_interval);
2562 }
2563 if (nilfs_test_opt(nilfs, DISCARD)) {
2564 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2565 sci->sc_nfreesegs);
2566 if (ret) {
2567 nilfs_warn(sb,
2568 "error %d on discard request, turning discards off for the device",
2569 ret);
2570 nilfs_clear_opt(nilfs, DISCARD);
2571 }
2572 }
2573
2574 out_unlock:
2575 sci->sc_freesegs = NULL;
2576 sci->sc_nfreesegs = 0;
2577 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2578 nilfs_transaction_unlock(sb);
2579 return err;
2580 }
2581
2582 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2583 {
2584 struct nilfs_transaction_info ti;
2585
2586 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2587 nilfs_segctor_construct(sci, mode);
2588
2589 /*
2590 * Unclosed segment should be retried. We do this using sc_timer.
2591 * Timeout of sc_timer will invoke complete construction which leads
2592 * to close the current logical segment.
2593 */
2594 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2595 nilfs_segctor_start_timer(sci);
2596
2597 nilfs_transaction_unlock(sci->sc_super);
2598 }
2599
2600 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2601 {
2602 int mode = 0;
2603
2604 spin_lock(&sci->sc_state_lock);
2605 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2606 SC_FLUSH_DAT : SC_FLUSH_FILE;
2607 spin_unlock(&sci->sc_state_lock);
2608
2609 if (mode) {
2610 nilfs_segctor_do_construct(sci, mode);
2611
2612 spin_lock(&sci->sc_state_lock);
2613 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2614 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2615 spin_unlock(&sci->sc_state_lock);
2616 }
2617 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2618 }
2619
2620 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2621 {
2622 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2623 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2624 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2625 return SC_FLUSH_FILE;
2626 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2627 return SC_FLUSH_DAT;
2628 }
2629 return SC_LSEG_SR;
2630 }
2631
2632 /**
2633 * nilfs_log_write_required - determine whether log writing is required
2634 * @sci: nilfs_sc_info struct
2635 * @modep: location for storing log writing mode
2636 *
2637 * Return: true if log writing is required, false otherwise. If log writing
2638 * is required, the mode is stored in the location pointed to by @modep.
2639 */
2640 static bool nilfs_log_write_required(struct nilfs_sc_info *sci, int *modep)
2641 {
2642 bool timedout, ret = true;
2643
2644 spin_lock(&sci->sc_state_lock);
2645 timedout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2646 time_after_eq(jiffies, sci->sc_timer.expires));
2647 if (timedout || sci->sc_seq_request != sci->sc_seq_done)
2648 *modep = SC_LSEG_SR;
2649 else if (sci->sc_flush_request)
2650 *modep = nilfs_segctor_flush_mode(sci);
2651 else
2652 ret = false;
2653
2654 spin_unlock(&sci->sc_state_lock);
2655 return ret;
2656 }
2657
2658 /**
2659 * nilfs_segctor_thread - main loop of the log writer thread
2660 * @arg: pointer to a struct nilfs_sc_info.
2661 *
2662 * nilfs_segctor_thread() is the main loop function of the log writer kernel
2663 * thread, which determines whether log writing is necessary, and if so,
2664 * performs the log write in the background, or waits if not. It is also
2665 * used to decide the background writeback of the superblock.
2666 *
2667 * Return: Always 0.
2668 */
2669 static int nilfs_segctor_thread(void *arg)
2670 {
2671 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2672 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2673
2674 nilfs_info(sci->sc_super,
2675 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
2676 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2677
2678 set_freezable();
2679
2680 while (!kthread_should_stop()) {
2681 DEFINE_WAIT(wait);
2682 bool should_write;
2683 int mode;
2684
2685 if (freezing(current)) {
2686 try_to_freeze();
2687 continue;
2688 }
2689
2690 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2691 TASK_INTERRUPTIBLE);
2692 should_write = nilfs_log_write_required(sci, &mode);
2693 if (!should_write)
2694 schedule();
2695 finish_wait(&sci->sc_wait_daemon, &wait);
2696
2697 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2698 set_nilfs_discontinued(nilfs);
2699
2700 if (should_write)
2701 nilfs_segctor_thread_construct(sci, mode);
2702 }
2703
2704 /* end sync. */
2705 spin_lock(&sci->sc_state_lock);
2706 sci->sc_task = NULL;
2707 timer_shutdown_sync(&sci->sc_timer);
2708 spin_unlock(&sci->sc_state_lock);
2709 return 0;
2710 }
2711
2712 /*
2713 * Setup & clean-up functions
2714 */
2715 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2716 struct nilfs_root *root)
2717 {
2718 struct the_nilfs *nilfs = sb->s_fs_info;
2719 struct nilfs_sc_info *sci;
2720
2721 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2722 if (!sci)
2723 return NULL;
2724
2725 sci->sc_super = sb;
2726
2727 nilfs_get_root(root);
2728 sci->sc_root = root;
2729
2730 init_waitqueue_head(&sci->sc_wait_request);
2731 init_waitqueue_head(&sci->sc_wait_daemon);
2732 spin_lock_init(&sci->sc_state_lock);
2733 INIT_LIST_HEAD(&sci->sc_dirty_files);
2734 INIT_LIST_HEAD(&sci->sc_segbufs);
2735 INIT_LIST_HEAD(&sci->sc_write_logs);
2736 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2737 INIT_LIST_HEAD(&sci->sc_iput_queue);
2738 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2739
2740 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2741 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2742 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2743
2744 if (nilfs->ns_interval)
2745 sci->sc_interval = HZ * nilfs->ns_interval;
2746 if (nilfs->ns_watermark)
2747 sci->sc_watermark = nilfs->ns_watermark;
2748 return sci;
2749 }
2750
2751 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2752 {
2753 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2754
2755 /*
2756 * The segctord thread was stopped and its timer was removed.
2757 * But some tasks remain.
2758 */
2759 do {
2760 struct nilfs_transaction_info ti;
2761
2762 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2763 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2764 nilfs_transaction_unlock(sci->sc_super);
2765
2766 flush_work(&sci->sc_iput_work);
2767
2768 } while (ret && ret != -EROFS && retrycount-- > 0);
2769 }
2770
2771 /**
2772 * nilfs_segctor_destroy - destroy the segment constructor.
2773 * @sci: nilfs_sc_info
2774 *
2775 * nilfs_segctor_destroy() kills the segctord thread and frees
2776 * the nilfs_sc_info struct.
2777 * Caller must hold the segment semaphore.
2778 */
2779 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2780 {
2781 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2782 int flag;
2783
2784 up_write(&nilfs->ns_segctor_sem);
2785
2786 if (sci->sc_task) {
2787 wake_up(&sci->sc_wait_daemon);
2788 kthread_stop(sci->sc_task);
2789 }
2790
2791 spin_lock(&sci->sc_state_lock);
2792 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2793 || sci->sc_seq_request != sci->sc_seq_done);
2794 spin_unlock(&sci->sc_state_lock);
2795
2796 /*
2797 * Forcibly wake up tasks waiting in nilfs_segctor_sync(), which can
2798 * be called from delayed iput() via nilfs_evict_inode() and can race
2799 * with the above log writer thread termination.
2800 */
2801 nilfs_segctor_wakeup(sci, 0, true);
2802
2803 if (flush_work(&sci->sc_iput_work))
2804 flag = true;
2805
2806 if (flag || !nilfs_segctor_confirm(sci))
2807 nilfs_segctor_write_out(sci);
2808
2809 if (!list_empty(&sci->sc_dirty_files)) {
2810 nilfs_warn(sci->sc_super,
2811 "disposed unprocessed dirty file(s) when stopping log writer");
2812 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2813 }
2814
2815 if (!list_empty(&sci->sc_iput_queue)) {
2816 nilfs_warn(sci->sc_super,
2817 "disposed unprocessed inode(s) in iput queue when stopping log writer");
2818 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2819 }
2820
2821 WARN_ON(!list_empty(&sci->sc_segbufs));
2822 WARN_ON(!list_empty(&sci->sc_write_logs));
2823
2824 nilfs_put_root(sci->sc_root);
2825
2826 down_write(&nilfs->ns_segctor_sem);
2827
2828 kfree(sci);
2829 }
2830
2831 /**
2832 * nilfs_attach_log_writer - attach log writer
2833 * @sb: super block instance
2834 * @root: root object of the current filesystem tree
2835 *
2836 * This allocates a log writer object, initializes it, and starts the
2837 * log writer.
2838 *
2839 * Return: 0 on success, or the following negative error code on failure.
2840 * * %-EINTR - Log writer thread creation failed due to interruption.
2841 * * %-ENOMEM - Insufficient memory available.
2842 */
2843 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2844 {
2845 struct the_nilfs *nilfs = sb->s_fs_info;
2846 struct nilfs_sc_info *sci;
2847 struct task_struct *t;
2848 int err;
2849
2850 if (nilfs->ns_writer) {
2851 /*
2852 * This happens if the filesystem is made read-only by
2853 * __nilfs_error or nilfs_remount and then remounted
2854 * read/write. In these cases, reuse the existing
2855 * writer.
2856 */
2857 return 0;
2858 }
2859
2860 sci = nilfs_segctor_new(sb, root);
2861 if (unlikely(!sci))
2862 return -ENOMEM;
2863
2864 nilfs->ns_writer = sci;
2865 t = kthread_create(nilfs_segctor_thread, sci, "segctord");
2866 if (IS_ERR(t)) {
2867 err = PTR_ERR(t);
2868 nilfs_err(sb, "error %d creating segctord thread", err);
2869 nilfs_detach_log_writer(sb);
2870 return err;
2871 }
2872 sci->sc_task = t;
2873 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
2874
2875 wake_up_process(sci->sc_task);
2876 return 0;
2877 }
2878
2879 /**
2880 * nilfs_detach_log_writer - destroy log writer
2881 * @sb: super block instance
2882 *
2883 * This kills log writer daemon, frees the log writer object, and
2884 * destroys list of dirty files.
2885 */
2886 void nilfs_detach_log_writer(struct super_block *sb)
2887 {
2888 struct the_nilfs *nilfs = sb->s_fs_info;
2889 LIST_HEAD(garbage_list);
2890
2891 down_write(&nilfs->ns_segctor_sem);
2892 if (nilfs->ns_writer) {
2893 nilfs_segctor_destroy(nilfs->ns_writer);
2894 nilfs->ns_writer = NULL;
2895 }
2896 set_nilfs_purging(nilfs);
2897
2898 /* Force to free the list of dirty files */
2899 spin_lock(&nilfs->ns_inode_lock);
2900 if (!list_empty(&nilfs->ns_dirty_files)) {
2901 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2902 nilfs_warn(sb,
2903 "disposed unprocessed dirty file(s) when detaching log writer");
2904 }
2905 spin_unlock(&nilfs->ns_inode_lock);
2906 up_write(&nilfs->ns_segctor_sem);
2907
2908 nilfs_dispose_list(nilfs, &garbage_list, 1);
2909 clear_nilfs_purging(nilfs);
2910 }
Linux Kernel