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io_uring: ensure finish_wait() is always called in __io_uring_task_cancel()
[linux/fpc-iii.git] / fs / nilfs2 / segment.c
blobcd4da9535aedcf7b279236bba0fb26234d2fe5b9
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 */
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) - (__s32)(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 (!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 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
434 {
435 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
436 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
437 return -E2BIG; /*
438 * The current segment is filled up
439 * (internal code)
440 */
441 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
442 return nilfs_segctor_reset_segment_buffer(sci);
443 }
444
445 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
446 {
447 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
448 int err;
449
450 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
451 err = nilfs_segctor_feed_segment(sci);
452 if (err)
453 return err;
454 segbuf = sci->sc_curseg;
455 }
456 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
457 if (likely(!err))
458 segbuf->sb_sum.flags |= NILFS_SS_SR;
459 return err;
460 }
461
462 /*
463 * Functions for making segment summary and payloads
464 */
465 static int nilfs_segctor_segsum_block_required(
466 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
467 unsigned int binfo_size)
468 {
469 unsigned int blocksize = sci->sc_super->s_blocksize;
470 /* Size of finfo and binfo is enough small against blocksize */
471
472 return ssp->offset + binfo_size +
473 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
474 blocksize;
475 }
476
477 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
478 struct inode *inode)
479 {
480 sci->sc_curseg->sb_sum.nfinfo++;
481 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
482 nilfs_segctor_map_segsum_entry(
483 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
484
485 if (NILFS_I(inode)->i_root &&
486 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
487 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
488 /* skip finfo */
489 }
490
491 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
492 struct inode *inode)
493 {
494 struct nilfs_finfo *finfo;
495 struct nilfs_inode_info *ii;
496 struct nilfs_segment_buffer *segbuf;
497 __u64 cno;
498
499 if (sci->sc_blk_cnt == 0)
500 return;
501
502 ii = NILFS_I(inode);
503
504 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
505 cno = ii->i_cno;
506 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
507 cno = 0;
508 else
509 cno = sci->sc_cno;
510
511 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
512 sizeof(*finfo));
513 finfo->fi_ino = cpu_to_le64(inode->i_ino);
514 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
515 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
516 finfo->fi_cno = cpu_to_le64(cno);
517
518 segbuf = sci->sc_curseg;
519 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
520 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
521 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
522 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
523 }
524
525 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
526 struct buffer_head *bh,
527 struct inode *inode,
528 unsigned int binfo_size)
529 {
530 struct nilfs_segment_buffer *segbuf;
531 int required, err = 0;
532
533 retry:
534 segbuf = sci->sc_curseg;
535 required = nilfs_segctor_segsum_block_required(
536 sci, &sci->sc_binfo_ptr, binfo_size);
537 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
538 nilfs_segctor_end_finfo(sci, inode);
539 err = nilfs_segctor_feed_segment(sci);
540 if (err)
541 return err;
542 goto retry;
543 }
544 if (unlikely(required)) {
545 err = nilfs_segbuf_extend_segsum(segbuf);
546 if (unlikely(err))
547 goto failed;
548 }
549 if (sci->sc_blk_cnt == 0)
550 nilfs_segctor_begin_finfo(sci, inode);
551
552 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
553 /* Substitution to vblocknr is delayed until update_blocknr() */
554 nilfs_segbuf_add_file_buffer(segbuf, bh);
555 sci->sc_blk_cnt++;
556 failed:
557 return err;
558 }
559
560 /*
561 * Callback functions that enumerate, mark, and collect dirty blocks
562 */
563 static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
564 struct buffer_head *bh, struct inode *inode)
565 {
566 int err;
567
568 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
569 if (err < 0)
570 return err;
571
572 err = nilfs_segctor_add_file_block(sci, bh, inode,
573 sizeof(struct nilfs_binfo_v));
574 if (!err)
575 sci->sc_datablk_cnt++;
576 return err;
577 }
578
579 static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
580 struct buffer_head *bh,
581 struct inode *inode)
582 {
583 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
584 }
585
586 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
587 struct buffer_head *bh,
588 struct inode *inode)
589 {
590 WARN_ON(!buffer_dirty(bh));
591 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
592 }
593
594 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
595 struct nilfs_segsum_pointer *ssp,
596 union nilfs_binfo *binfo)
597 {
598 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
599 sci, ssp, sizeof(*binfo_v));
600 *binfo_v = binfo->bi_v;
601 }
602
603 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
604 struct nilfs_segsum_pointer *ssp,
605 union nilfs_binfo *binfo)
606 {
607 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
608 sci, ssp, sizeof(*vblocknr));
609 *vblocknr = binfo->bi_v.bi_vblocknr;
610 }
611
612 static const struct nilfs_sc_operations nilfs_sc_file_ops = {
613 .collect_data = nilfs_collect_file_data,
614 .collect_node = nilfs_collect_file_node,
615 .collect_bmap = nilfs_collect_file_bmap,
616 .write_data_binfo = nilfs_write_file_data_binfo,
617 .write_node_binfo = nilfs_write_file_node_binfo,
618 };
619
620 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
621 struct buffer_head *bh, struct inode *inode)
622 {
623 int err;
624
625 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
626 if (err < 0)
627 return err;
628
629 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
630 if (!err)
631 sci->sc_datablk_cnt++;
632 return err;
633 }
634
635 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
636 struct buffer_head *bh, struct inode *inode)
637 {
638 WARN_ON(!buffer_dirty(bh));
639 return nilfs_segctor_add_file_block(sci, bh, inode,
640 sizeof(struct nilfs_binfo_dat));
641 }
642
643 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
644 struct nilfs_segsum_pointer *ssp,
645 union nilfs_binfo *binfo)
646 {
647 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
648 sizeof(*blkoff));
649 *blkoff = binfo->bi_dat.bi_blkoff;
650 }
651
652 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
653 struct nilfs_segsum_pointer *ssp,
654 union nilfs_binfo *binfo)
655 {
656 struct nilfs_binfo_dat *binfo_dat =
657 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
658 *binfo_dat = binfo->bi_dat;
659 }
660
661 static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
662 .collect_data = nilfs_collect_dat_data,
663 .collect_node = nilfs_collect_file_node,
664 .collect_bmap = nilfs_collect_dat_bmap,
665 .write_data_binfo = nilfs_write_dat_data_binfo,
666 .write_node_binfo = nilfs_write_dat_node_binfo,
667 };
668
669 static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
670 .collect_data = nilfs_collect_file_data,
671 .collect_node = NULL,
672 .collect_bmap = NULL,
673 .write_data_binfo = nilfs_write_file_data_binfo,
674 .write_node_binfo = NULL,
675 };
676
677 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
678 struct list_head *listp,
679 size_t nlimit,
680 loff_t start, loff_t end)
681 {
682 struct address_space *mapping = inode->i_mapping;
683 struct pagevec pvec;
684 pgoff_t index = 0, last = ULONG_MAX;
685 size_t ndirties = 0;
686 int i;
687
688 if (unlikely(start != 0 || end != LLONG_MAX)) {
689 /*
690 * A valid range is given for sync-ing data pages. The
691 * range is rounded to per-page; extra dirty buffers
692 * may be included if blocksize < pagesize.
693 */
694 index = start >> PAGE_SHIFT;
695 last = end >> PAGE_SHIFT;
696 }
697 pagevec_init(&pvec);
698 repeat:
699 if (unlikely(index > last) ||
700 !pagevec_lookup_range_tag(&pvec, mapping, &index, last,
701 PAGECACHE_TAG_DIRTY))
702 return ndirties;
703
704 for (i = 0; i < pagevec_count(&pvec); i++) {
705 struct buffer_head *bh, *head;
706 struct page *page = pvec.pages[i];
707
708 lock_page(page);
709 if (!page_has_buffers(page))
710 create_empty_buffers(page, i_blocksize(inode), 0);
711 unlock_page(page);
712
713 bh = head = page_buffers(page);
714 do {
715 if (!buffer_dirty(bh) || buffer_async_write(bh))
716 continue;
717 get_bh(bh);
718 list_add_tail(&bh->b_assoc_buffers, listp);
719 ndirties++;
720 if (unlikely(ndirties >= nlimit)) {
721 pagevec_release(&pvec);
722 cond_resched();
723 return ndirties;
724 }
725 } while (bh = bh->b_this_page, bh != head);
726 }
727 pagevec_release(&pvec);
728 cond_resched();
729 goto repeat;
730 }
731
732 static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
733 struct list_head *listp)
734 {
735 struct nilfs_inode_info *ii = NILFS_I(inode);
736 struct address_space *mapping = &ii->i_btnode_cache;
737 struct pagevec pvec;
738 struct buffer_head *bh, *head;
739 unsigned int i;
740 pgoff_t index = 0;
741
742 pagevec_init(&pvec);
743
744 while (pagevec_lookup_tag(&pvec, mapping, &index,
745 PAGECACHE_TAG_DIRTY)) {
746 for (i = 0; i < pagevec_count(&pvec); i++) {
747 bh = head = page_buffers(pvec.pages[i]);
748 do {
749 if (buffer_dirty(bh) &&
750 !buffer_async_write(bh)) {
751 get_bh(bh);
752 list_add_tail(&bh->b_assoc_buffers,
753 listp);
754 }
755 bh = bh->b_this_page;
756 } while (bh != head);
757 }
758 pagevec_release(&pvec);
759 cond_resched();
760 }
761 }
762
763 static void nilfs_dispose_list(struct the_nilfs *nilfs,
764 struct list_head *head, int force)
765 {
766 struct nilfs_inode_info *ii, *n;
767 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
768 unsigned int nv = 0;
769
770 while (!list_empty(head)) {
771 spin_lock(&nilfs->ns_inode_lock);
772 list_for_each_entry_safe(ii, n, head, i_dirty) {
773 list_del_init(&ii->i_dirty);
774 if (force) {
775 if (unlikely(ii->i_bh)) {
776 brelse(ii->i_bh);
777 ii->i_bh = NULL;
778 }
779 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
780 set_bit(NILFS_I_QUEUED, &ii->i_state);
781 list_add_tail(&ii->i_dirty,
782 &nilfs->ns_dirty_files);
783 continue;
784 }
785 ivec[nv++] = ii;
786 if (nv == SC_N_INODEVEC)
787 break;
788 }
789 spin_unlock(&nilfs->ns_inode_lock);
790
791 for (pii = ivec; nv > 0; pii++, nv--)
792 iput(&(*pii)->vfs_inode);
793 }
794 }
795
796 static void nilfs_iput_work_func(struct work_struct *work)
797 {
798 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
799 sc_iput_work);
800 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
801
802 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
803 }
804
805 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
806 struct nilfs_root *root)
807 {
808 int ret = 0;
809
810 if (nilfs_mdt_fetch_dirty(root->ifile))
811 ret++;
812 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
813 ret++;
814 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
815 ret++;
816 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
817 ret++;
818 return ret;
819 }
820
821 static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
822 {
823 return list_empty(&sci->sc_dirty_files) &&
824 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
825 sci->sc_nfreesegs == 0 &&
826 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
827 }
828
829 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
830 {
831 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
832 int ret = 0;
833
834 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
835 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
836
837 spin_lock(&nilfs->ns_inode_lock);
838 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
839 ret++;
840
841 spin_unlock(&nilfs->ns_inode_lock);
842 return ret;
843 }
844
845 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
846 {
847 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
848
849 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
850 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
851 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
852 nilfs_mdt_clear_dirty(nilfs->ns_dat);
853 }
854
855 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
856 {
857 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
858 struct buffer_head *bh_cp;
859 struct nilfs_checkpoint *raw_cp;
860 int err;
861
862 /* XXX: this interface will be changed */
863 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
864 &raw_cp, &bh_cp);
865 if (likely(!err)) {
866 /*
867 * The following code is duplicated with cpfile. But, it is
868 * needed to collect the checkpoint even if it was not newly
869 * created.
870 */
871 mark_buffer_dirty(bh_cp);
872 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
873 nilfs_cpfile_put_checkpoint(
874 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
875 } else
876 WARN_ON(err == -EINVAL || err == -ENOENT);
877
878 return err;
879 }
880
881 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
882 {
883 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
884 struct buffer_head *bh_cp;
885 struct nilfs_checkpoint *raw_cp;
886 int err;
887
888 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
889 &raw_cp, &bh_cp);
890 if (unlikely(err)) {
891 WARN_ON(err == -EINVAL || err == -ENOENT);
892 goto failed_ibh;
893 }
894 raw_cp->cp_snapshot_list.ssl_next = 0;
895 raw_cp->cp_snapshot_list.ssl_prev = 0;
896 raw_cp->cp_inodes_count =
897 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
898 raw_cp->cp_blocks_count =
899 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
900 raw_cp->cp_nblk_inc =
901 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
902 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
903 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
904
905 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
906 nilfs_checkpoint_clear_minor(raw_cp);
907 else
908 nilfs_checkpoint_set_minor(raw_cp);
909
910 nilfs_write_inode_common(sci->sc_root->ifile,
911 &raw_cp->cp_ifile_inode, 1);
912 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
913 return 0;
914
915 failed_ibh:
916 return err;
917 }
918
919 static void nilfs_fill_in_file_bmap(struct inode *ifile,
920 struct nilfs_inode_info *ii)
921
922 {
923 struct buffer_head *ibh;
924 struct nilfs_inode *raw_inode;
925
926 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
927 ibh = ii->i_bh;
928 BUG_ON(!ibh);
929 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
930 ibh);
931 nilfs_bmap_write(ii->i_bmap, raw_inode);
932 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
933 }
934 }
935
936 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
937 {
938 struct nilfs_inode_info *ii;
939
940 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
941 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
942 set_bit(NILFS_I_COLLECTED, &ii->i_state);
943 }
944 }
945
946 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
947 struct the_nilfs *nilfs)
948 {
949 struct buffer_head *bh_sr;
950 struct nilfs_super_root *raw_sr;
951 unsigned int isz, srsz;
952
953 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
954 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
955 isz = nilfs->ns_inode_size;
956 srsz = NILFS_SR_BYTES(isz);
957
958 raw_sr->sr_bytes = cpu_to_le16(srsz);
959 raw_sr->sr_nongc_ctime
960 = cpu_to_le64(nilfs_doing_gc() ?
961 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
962 raw_sr->sr_flags = 0;
963
964 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
965 NILFS_SR_DAT_OFFSET(isz), 1);
966 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
967 NILFS_SR_CPFILE_OFFSET(isz), 1);
968 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
969 NILFS_SR_SUFILE_OFFSET(isz), 1);
970 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
971 }
972
973 static void nilfs_redirty_inodes(struct list_head *head)
974 {
975 struct nilfs_inode_info *ii;
976
977 list_for_each_entry(ii, head, i_dirty) {
978 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
979 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
980 }
981 }
982
983 static void nilfs_drop_collected_inodes(struct list_head *head)
984 {
985 struct nilfs_inode_info *ii;
986
987 list_for_each_entry(ii, head, i_dirty) {
988 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
989 continue;
990
991 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
992 set_bit(NILFS_I_UPDATED, &ii->i_state);
993 }
994 }
995
996 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
997 struct inode *inode,
998 struct list_head *listp,
999 int (*collect)(struct nilfs_sc_info *,
1000 struct buffer_head *,
1001 struct inode *))
1002 {
1003 struct buffer_head *bh, *n;
1004 int err = 0;
1005
1006 if (collect) {
1007 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1008 list_del_init(&bh->b_assoc_buffers);
1009 err = collect(sci, bh, inode);
1010 brelse(bh);
1011 if (unlikely(err))
1012 goto dispose_buffers;
1013 }
1014 return 0;
1015 }
1016
1017 dispose_buffers:
1018 while (!list_empty(listp)) {
1019 bh = list_first_entry(listp, struct buffer_head,
1020 b_assoc_buffers);
1021 list_del_init(&bh->b_assoc_buffers);
1022 brelse(bh);
1023 }
1024 return err;
1025 }
1026
1027 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1028 {
1029 /* Remaining number of blocks within segment buffer */
1030 return sci->sc_segbuf_nblocks -
1031 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1032 }
1033
1034 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1035 struct inode *inode,
1036 const struct nilfs_sc_operations *sc_ops)
1037 {
1038 LIST_HEAD(data_buffers);
1039 LIST_HEAD(node_buffers);
1040 int err;
1041
1042 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1043 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1044
1045 n = nilfs_lookup_dirty_data_buffers(
1046 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1047 if (n > rest) {
1048 err = nilfs_segctor_apply_buffers(
1049 sci, inode, &data_buffers,
1050 sc_ops->collect_data);
1051 BUG_ON(!err); /* always receive -E2BIG or true error */
1052 goto break_or_fail;
1053 }
1054 }
1055 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1056
1057 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1058 err = nilfs_segctor_apply_buffers(
1059 sci, inode, &data_buffers, sc_ops->collect_data);
1060 if (unlikely(err)) {
1061 /* dispose node list */
1062 nilfs_segctor_apply_buffers(
1063 sci, inode, &node_buffers, NULL);
1064 goto break_or_fail;
1065 }
1066 sci->sc_stage.flags |= NILFS_CF_NODE;
1067 }
1068 /* Collect node */
1069 err = nilfs_segctor_apply_buffers(
1070 sci, inode, &node_buffers, sc_ops->collect_node);
1071 if (unlikely(err))
1072 goto break_or_fail;
1073
1074 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1075 err = nilfs_segctor_apply_buffers(
1076 sci, inode, &node_buffers, sc_ops->collect_bmap);
1077 if (unlikely(err))
1078 goto break_or_fail;
1079
1080 nilfs_segctor_end_finfo(sci, inode);
1081 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1082
1083 break_or_fail:
1084 return err;
1085 }
1086
1087 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1088 struct inode *inode)
1089 {
1090 LIST_HEAD(data_buffers);
1091 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1092 int err;
1093
1094 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1095 sci->sc_dsync_start,
1096 sci->sc_dsync_end);
1097
1098 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1099 nilfs_collect_file_data);
1100 if (!err) {
1101 nilfs_segctor_end_finfo(sci, inode);
1102 BUG_ON(n > rest);
1103 /* always receive -E2BIG or true error if n > rest */
1104 }
1105 return err;
1106 }
1107
1108 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1109 {
1110 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1111 struct list_head *head;
1112 struct nilfs_inode_info *ii;
1113 size_t ndone;
1114 int err = 0;
1115
1116 switch (nilfs_sc_cstage_get(sci)) {
1117 case NILFS_ST_INIT:
1118 /* Pre-processes */
1119 sci->sc_stage.flags = 0;
1120
1121 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1122 sci->sc_nblk_inc = 0;
1123 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1124 if (mode == SC_LSEG_DSYNC) {
1125 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1126 goto dsync_mode;
1127 }
1128 }
1129
1130 sci->sc_stage.dirty_file_ptr = NULL;
1131 sci->sc_stage.gc_inode_ptr = NULL;
1132 if (mode == SC_FLUSH_DAT) {
1133 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1134 goto dat_stage;
1135 }
1136 nilfs_sc_cstage_inc(sci);
1137 fallthrough;
1138 case NILFS_ST_GC:
1139 if (nilfs_doing_gc()) {
1140 head = &sci->sc_gc_inodes;
1141 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1142 head, i_dirty);
1143 list_for_each_entry_continue(ii, head, i_dirty) {
1144 err = nilfs_segctor_scan_file(
1145 sci, &ii->vfs_inode,
1146 &nilfs_sc_file_ops);
1147 if (unlikely(err)) {
1148 sci->sc_stage.gc_inode_ptr = list_entry(
1149 ii->i_dirty.prev,
1150 struct nilfs_inode_info,
1151 i_dirty);
1152 goto break_or_fail;
1153 }
1154 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1155 }
1156 sci->sc_stage.gc_inode_ptr = NULL;
1157 }
1158 nilfs_sc_cstage_inc(sci);
1159 fallthrough;
1160 case NILFS_ST_FILE:
1161 head = &sci->sc_dirty_files;
1162 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1163 i_dirty);
1164 list_for_each_entry_continue(ii, head, i_dirty) {
1165 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1166
1167 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1168 &nilfs_sc_file_ops);
1169 if (unlikely(err)) {
1170 sci->sc_stage.dirty_file_ptr =
1171 list_entry(ii->i_dirty.prev,
1172 struct nilfs_inode_info,
1173 i_dirty);
1174 goto break_or_fail;
1175 }
1176 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1177 /* XXX: required ? */
1178 }
1179 sci->sc_stage.dirty_file_ptr = NULL;
1180 if (mode == SC_FLUSH_FILE) {
1181 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1182 return 0;
1183 }
1184 nilfs_sc_cstage_inc(sci);
1185 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1186 fallthrough;
1187 case NILFS_ST_IFILE:
1188 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1189 &nilfs_sc_file_ops);
1190 if (unlikely(err))
1191 break;
1192 nilfs_sc_cstage_inc(sci);
1193 /* Creating a checkpoint */
1194 err = nilfs_segctor_create_checkpoint(sci);
1195 if (unlikely(err))
1196 break;
1197 fallthrough;
1198 case NILFS_ST_CPFILE:
1199 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1200 &nilfs_sc_file_ops);
1201 if (unlikely(err))
1202 break;
1203 nilfs_sc_cstage_inc(sci);
1204 fallthrough;
1205 case NILFS_ST_SUFILE:
1206 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1207 sci->sc_nfreesegs, &ndone);
1208 if (unlikely(err)) {
1209 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1210 sci->sc_freesegs, ndone,
1211 NULL);
1212 break;
1213 }
1214 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1215
1216 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1217 &nilfs_sc_file_ops);
1218 if (unlikely(err))
1219 break;
1220 nilfs_sc_cstage_inc(sci);
1221 fallthrough;
1222 case NILFS_ST_DAT:
1223 dat_stage:
1224 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1225 &nilfs_sc_dat_ops);
1226 if (unlikely(err))
1227 break;
1228 if (mode == SC_FLUSH_DAT) {
1229 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1230 return 0;
1231 }
1232 nilfs_sc_cstage_inc(sci);
1233 fallthrough;
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 */
1273 static 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
1333 static 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
1389 static 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
1428 static 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
1445 static 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
1463 static 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
1479 static 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
1532 static 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
1541 static int
1542 nilfs_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
1614 static 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
1628 static 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
1643 static 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
1692 static 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
1702 static 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
1740 static 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
1781 static 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
1806 static 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
1817 static 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
1914 static 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
1926 static 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_warn(sci->sc_super,
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
1969 static 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 */
2008 static 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 */
2112 static 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
2123 static 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 */
2141 void 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
2152 struct nilfs_segctor_wait_request {
2153 wait_queue_entry_t wq;
2154 __u32 seq;
2155 int err;
2156 atomic_t done;
2157 };
2158
2159 static 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
2192 static 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 */
2230 int 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 */
2267 int 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 */
2318 static 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 */
2332 static 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 */
2361 static 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
2396 static 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
2403 static void
2404 nilfs_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
2418 int 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_warn(sb, "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_warn(sb,
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
2475 static 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
2493 static 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
2513 static 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 */
2532 static 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_info(sci->sc_super,
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
2611 static 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_err(sci->sc_super, "error %d creating segctord thread",
2620 err);
2621 return err;
2622 }
2623 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2624 return 0;
2625 }
2626
2627 static 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 */
2644 static 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
2682 static 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 */
2710 static 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_warn(sci->sc_super,
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_warn(sci->sc_super,
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 */
2765 int 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 inode_attach_wb(nilfs->ns_bdev->bd_inode, NULL);
2784
2785 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2786 if (err) {
2787 kfree(nilfs->ns_writer);
2788 nilfs->ns_writer = NULL;
2789 }
2790 return err;
2791 }
2792
2793 /**
2794 * nilfs_detach_log_writer - destroy log writer
2795 * @sb: super block instance
2796 *
2797 * This kills log writer daemon, frees the log writer object, and
2798 * destroys list of dirty files.
2799 */
2800 void nilfs_detach_log_writer(struct super_block *sb)
2801 {
2802 struct the_nilfs *nilfs = sb->s_fs_info;
2803 LIST_HEAD(garbage_list);
2804
2805 down_write(&nilfs->ns_segctor_sem);
2806 if (nilfs->ns_writer) {
2807 nilfs_segctor_destroy(nilfs->ns_writer);
2808 nilfs->ns_writer = NULL;
2809 }
2810
2811 /* Force to free the list of dirty files */
2812 spin_lock(&nilfs->ns_inode_lock);
2813 if (!list_empty(&nilfs->ns_dirty_files)) {
2814 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2815 nilfs_warn(sb,
2816 "disposed unprocessed dirty file(s) when detaching log writer");
2817 }
2818 spin_unlock(&nilfs->ns_inode_lock);
2819 up_write(&nilfs->ns_segctor_sem);
2820
2821 nilfs_dispose_list(nilfs, &garbage_list, 1);
2822 }
Linux with added FPC-III support