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1/*
2 * segment.c - NILFS segment constructor.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * Written by Ryusuke Konishi.
17 *
18 */
19
20#include <linux/pagemap.h>
21#include <linux/buffer_head.h>
22#include <linux/writeback.h>
23#include <linux/bitops.h>
24#include <linux/bio.h>
25#include <linux/completion.h>
26#include <linux/blkdev.h>
27#include <linux/backing-dev.h>
28#include <linux/freezer.h>
29#include <linux/kthread.h>
30#include <linux/crc32.h>
31#include <linux/pagevec.h>
32#include <linux/slab.h>
33#include <linux/sched/signal.h>
34
35#include "nilfs.h"
36#include "btnode.h"
37#include "page.h"
38#include "segment.h"
39#include "sufile.h"
40#include "cpfile.h"
41#include "ifile.h"
42#include "segbuf.h"
43
44
45/*
46 * Segment constructor
47 */
48#define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
49
50#define SC_MAX_SEGDELTA 64 /*
51 * Upper limit of the number of segments
52 * appended in collection retry loop
53 */
54
55/* Construction mode */
56enum {
57 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
58 SC_LSEG_DSYNC, /*
59 * Flush data blocks of a given file and make
60 * a logical segment without a super root.
61 */
62 SC_FLUSH_FILE, /*
63 * Flush data files, leads to segment writes without
64 * creating a checkpoint.
65 */
66 SC_FLUSH_DAT, /*
67 * Flush DAT file. This also creates segments
68 * without a checkpoint.
69 */
70};
71
72/* Stage numbers of dirty block collection */
73enum {
74 NILFS_ST_INIT = 0,
75 NILFS_ST_GC, /* Collecting dirty blocks for GC */
76 NILFS_ST_FILE,
77 NILFS_ST_IFILE,
78 NILFS_ST_CPFILE,
79 NILFS_ST_SUFILE,
80 NILFS_ST_DAT,
81 NILFS_ST_SR, /* Super root */
82 NILFS_ST_DSYNC, /* Data sync blocks */
83 NILFS_ST_DONE,
84};
85
86#define CREATE_TRACE_POINTS
87#include <trace/events/nilfs2.h>
88
89/*
90 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
91 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
92 * the variable must use them because transition of stage count must involve
93 * trace events (trace_nilfs2_collection_stage_transition).
94 *
95 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
96 * produce tracepoint events. It is provided just for making the intention
97 * clear.
98 */
99static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
100{
101 sci->sc_stage.scnt++;
102 trace_nilfs2_collection_stage_transition(sci);
103}
104
105static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
106{
107 sci->sc_stage.scnt = next_scnt;
108 trace_nilfs2_collection_stage_transition(sci);
109}
110
111static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
112{
113 return sci->sc_stage.scnt;
114}
115
116/* State flags of collection */
117#define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
118#define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
119#define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
120#define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
121
122/* Operations depending on the construction mode and file type */
123struct nilfs_sc_operations {
124 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
125 struct inode *);
126 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
127 struct inode *);
128 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
129 struct inode *);
130 void (*write_data_binfo)(struct nilfs_sc_info *,
131 struct nilfs_segsum_pointer *,
132 union nilfs_binfo *);
133 void (*write_node_binfo)(struct nilfs_sc_info *,
134 struct nilfs_segsum_pointer *,
135 union nilfs_binfo *);
136};
137
138/*
139 * Other definitions
140 */
141static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
142static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
143static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
144static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
145
146#define nilfs_cnt32_gt(a, b) \
147 (typecheck(__u32, a) && typecheck(__u32, b) && \
148 ((__s32)(b) - (__s32)(a) < 0))
149#define nilfs_cnt32_ge(a, b) \
150 (typecheck(__u32, a) && typecheck(__u32, b) && \
151 ((__s32)(a) - (__s32)(b) >= 0))
152#define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
153#define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
154
155static int nilfs_prepare_segment_lock(struct super_block *sb,
156 struct nilfs_transaction_info *ti)
157{
158 struct nilfs_transaction_info *cur_ti = current->journal_info;
159 void *save = NULL;
160
161 if (cur_ti) {
162 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
163 return ++cur_ti->ti_count;
164
165 /*
166 * If journal_info field is occupied by other FS,
167 * it is saved and will be restored on
168 * nilfs_transaction_commit().
169 */
170 nilfs_msg(sb, KERN_WARNING, "journal info from a different FS");
171 save = current->journal_info;
172 }
173 if (!ti) {
174 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
175 if (!ti)
176 return -ENOMEM;
177 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
178 } else {
179 ti->ti_flags = 0;
180 }
181 ti->ti_count = 0;
182 ti->ti_save = save;
183 ti->ti_magic = NILFS_TI_MAGIC;
184 current->journal_info = ti;
185 return 0;
186}
187
188/**
189 * nilfs_transaction_begin - start indivisible file operations.
190 * @sb: super block
191 * @ti: nilfs_transaction_info
192 * @vacancy_check: flags for vacancy rate checks
193 *
194 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
195 * the segment semaphore, to make a segment construction and write tasks
196 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
197 * The region enclosed by these two functions can be nested. To avoid a
198 * deadlock, the semaphore is only acquired or released in the outermost call.
199 *
200 * This function allocates a nilfs_transaction_info struct to keep context
201 * information on it. It is initialized and hooked onto the current task in
202 * the outermost call. If a pre-allocated struct is given to @ti, it is used
203 * instead; otherwise a new struct is assigned from a slab.
204 *
205 * When @vacancy_check flag is set, this function will check the amount of
206 * free space, and will wait for the GC to reclaim disk space if low capacity.
207 *
208 * Return Value: On success, 0 is returned. On error, one of the following
209 * negative error code is returned.
210 *
211 * %-ENOMEM - Insufficient memory available.
212 *
213 * %-ENOSPC - No space left on device
214 */
215int nilfs_transaction_begin(struct super_block *sb,
216 struct nilfs_transaction_info *ti,
217 int vacancy_check)
218{
219 struct the_nilfs *nilfs;
220 int ret = nilfs_prepare_segment_lock(sb, ti);
221 struct nilfs_transaction_info *trace_ti;
222
223 if (unlikely(ret < 0))
224 return ret;
225 if (ret > 0) {
226 trace_ti = current->journal_info;
227
228 trace_nilfs2_transaction_transition(sb, trace_ti,
229 trace_ti->ti_count, trace_ti->ti_flags,
230 TRACE_NILFS2_TRANSACTION_BEGIN);
231 return 0;
232 }
233
234 sb_start_intwrite(sb);
235
236 nilfs = sb->s_fs_info;
237 down_read(&nilfs->ns_segctor_sem);
238 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
239 up_read(&nilfs->ns_segctor_sem);
240 ret = -ENOSPC;
241 goto failed;
242 }
243
244 trace_ti = current->journal_info;
245 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
246 trace_ti->ti_flags,
247 TRACE_NILFS2_TRANSACTION_BEGIN);
248 return 0;
249
250 failed:
251 ti = current->journal_info;
252 current->journal_info = ti->ti_save;
253 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
254 kmem_cache_free(nilfs_transaction_cachep, ti);
255 sb_end_intwrite(sb);
256 return ret;
257}
258
259/**
260 * nilfs_transaction_commit - commit indivisible file operations.
261 * @sb: super block
262 *
263 * nilfs_transaction_commit() releases the read semaphore which is
264 * acquired by nilfs_transaction_begin(). This is only performed
265 * in outermost call of this function. If a commit flag is set,
266 * nilfs_transaction_commit() sets a timer to start the segment
267 * constructor. If a sync flag is set, it starts construction
268 * directly.
269 */
270int nilfs_transaction_commit(struct super_block *sb)
271{
272 struct nilfs_transaction_info *ti = current->journal_info;
273 struct the_nilfs *nilfs = sb->s_fs_info;
274 int err = 0;
275
276 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
277 ti->ti_flags |= NILFS_TI_COMMIT;
278 if (ti->ti_count > 0) {
279 ti->ti_count--;
280 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
281 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
282 return 0;
283 }
284 if (nilfs->ns_writer) {
285 struct nilfs_sc_info *sci = nilfs->ns_writer;
286
287 if (ti->ti_flags & NILFS_TI_COMMIT)
288 nilfs_segctor_start_timer(sci);
289 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
290 nilfs_segctor_do_flush(sci, 0);
291 }
292 up_read(&nilfs->ns_segctor_sem);
293 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
294 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
295
296 current->journal_info = ti->ti_save;
297
298 if (ti->ti_flags & NILFS_TI_SYNC)
299 err = nilfs_construct_segment(sb);
300 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
301 kmem_cache_free(nilfs_transaction_cachep, ti);
302 sb_end_intwrite(sb);
303 return err;
304}
305
306void nilfs_transaction_abort(struct super_block *sb)
307{
308 struct nilfs_transaction_info *ti = current->journal_info;
309 struct the_nilfs *nilfs = sb->s_fs_info;
310
311 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
312 if (ti->ti_count > 0) {
313 ti->ti_count--;
314 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
315 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
316 return;
317 }
318 up_read(&nilfs->ns_segctor_sem);
319
320 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
321 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
322
323 current->journal_info = ti->ti_save;
324 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
325 kmem_cache_free(nilfs_transaction_cachep, ti);
326 sb_end_intwrite(sb);
327}
328
329void nilfs_relax_pressure_in_lock(struct super_block *sb)
330{
331 struct the_nilfs *nilfs = sb->s_fs_info;
332 struct nilfs_sc_info *sci = nilfs->ns_writer;
333
334 if (!sci || !sci->sc_flush_request)
335 return;
336
337 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
338 up_read(&nilfs->ns_segctor_sem);
339
340 down_write(&nilfs->ns_segctor_sem);
341 if (sci->sc_flush_request &&
342 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
343 struct nilfs_transaction_info *ti = current->journal_info;
344
345 ti->ti_flags |= NILFS_TI_WRITER;
346 nilfs_segctor_do_immediate_flush(sci);
347 ti->ti_flags &= ~NILFS_TI_WRITER;
348 }
349 downgrade_write(&nilfs->ns_segctor_sem);
350}
351
352static void nilfs_transaction_lock(struct super_block *sb,
353 struct nilfs_transaction_info *ti,
354 int gcflag)
355{
356 struct nilfs_transaction_info *cur_ti = current->journal_info;
357 struct the_nilfs *nilfs = sb->s_fs_info;
358 struct nilfs_sc_info *sci = nilfs->ns_writer;
359
360 WARN_ON(cur_ti);
361 ti->ti_flags = NILFS_TI_WRITER;
362 ti->ti_count = 0;
363 ti->ti_save = cur_ti;
364 ti->ti_magic = NILFS_TI_MAGIC;
365 current->journal_info = ti;
366
367 for (;;) {
368 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
369 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
370
371 down_write(&nilfs->ns_segctor_sem);
372 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
373 break;
374
375 nilfs_segctor_do_immediate_flush(sci);
376
377 up_write(&nilfs->ns_segctor_sem);
378 cond_resched();
379 }
380 if (gcflag)
381 ti->ti_flags |= NILFS_TI_GC;
382
383 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
384 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
385}
386
387static void nilfs_transaction_unlock(struct super_block *sb)
388{
389 struct nilfs_transaction_info *ti = current->journal_info;
390 struct the_nilfs *nilfs = sb->s_fs_info;
391
392 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
393 BUG_ON(ti->ti_count > 0);
394
395 up_write(&nilfs->ns_segctor_sem);
396 current->journal_info = ti->ti_save;
397
398 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
399 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
400}
401
402static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
403 struct nilfs_segsum_pointer *ssp,
404 unsigned int bytes)
405{
406 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
407 unsigned int blocksize = sci->sc_super->s_blocksize;
408 void *p;
409
410 if (unlikely(ssp->offset + bytes > blocksize)) {
411 ssp->offset = 0;
412 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
413 &segbuf->sb_segsum_buffers));
414 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
415 }
416 p = ssp->bh->b_data + ssp->offset;
417 ssp->offset += bytes;
418 return p;
419}
420
421/**
422 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
423 * @sci: nilfs_sc_info
424 */
425static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
426{
427 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
428 struct buffer_head *sumbh;
429 unsigned int sumbytes;
430 unsigned int flags = 0;
431 int err;
432
433 if (nilfs_doing_gc())
434 flags = NILFS_SS_GC;
435 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
436 if (unlikely(err))
437 return err;
438
439 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
440 sumbytes = segbuf->sb_sum.sumbytes;
441 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
442 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
443 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
444 return 0;
445}
446
447static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
448{
449 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
450 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
451 return -E2BIG; /*
452 * The current segment is filled up
453 * (internal code)
454 */
455 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
456 return nilfs_segctor_reset_segment_buffer(sci);
457}
458
459static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
460{
461 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
462 int err;
463
464 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
465 err = nilfs_segctor_feed_segment(sci);
466 if (err)
467 return err;
468 segbuf = sci->sc_curseg;
469 }
470 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
471 if (likely(!err))
472 segbuf->sb_sum.flags |= NILFS_SS_SR;
473 return err;
474}
475
476/*
477 * Functions for making segment summary and payloads
478 */
479static int nilfs_segctor_segsum_block_required(
480 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
481 unsigned int binfo_size)
482{
483 unsigned int blocksize = sci->sc_super->s_blocksize;
484 /* Size of finfo and binfo is enough small against blocksize */
485
486 return ssp->offset + binfo_size +
487 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
488 blocksize;
489}
490
491static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
492 struct inode *inode)
493{
494 sci->sc_curseg->sb_sum.nfinfo++;
495 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
496 nilfs_segctor_map_segsum_entry(
497 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
498
499 if (NILFS_I(inode)->i_root &&
500 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
501 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
502 /* skip finfo */
503}
504
505static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
506 struct inode *inode)
507{
508 struct nilfs_finfo *finfo;
509 struct nilfs_inode_info *ii;
510 struct nilfs_segment_buffer *segbuf;
511 __u64 cno;
512
513 if (sci->sc_blk_cnt == 0)
514 return;
515
516 ii = NILFS_I(inode);
517
518 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
519 cno = ii->i_cno;
520 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
521 cno = 0;
522 else
523 cno = sci->sc_cno;
524
525 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
526 sizeof(*finfo));
527 finfo->fi_ino = cpu_to_le64(inode->i_ino);
528 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
529 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
530 finfo->fi_cno = cpu_to_le64(cno);
531
532 segbuf = sci->sc_curseg;
533 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
534 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
535 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
536 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
537}
538
539static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
540 struct buffer_head *bh,
541 struct inode *inode,
542 unsigned int binfo_size)
543{
544 struct nilfs_segment_buffer *segbuf;
545 int required, err = 0;
546
547 retry:
548 segbuf = sci->sc_curseg;
549 required = nilfs_segctor_segsum_block_required(
550 sci, &sci->sc_binfo_ptr, binfo_size);
551 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
552 nilfs_segctor_end_finfo(sci, inode);
553 err = nilfs_segctor_feed_segment(sci);
554 if (err)
555 return err;
556 goto retry;
557 }
558 if (unlikely(required)) {
559 err = nilfs_segbuf_extend_segsum(segbuf);
560 if (unlikely(err))
561 goto failed;
562 }
563 if (sci->sc_blk_cnt == 0)
564 nilfs_segctor_begin_finfo(sci, inode);
565
566 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
567 /* Substitution to vblocknr is delayed until update_blocknr() */
568 nilfs_segbuf_add_file_buffer(segbuf, bh);
569 sci->sc_blk_cnt++;
570 failed:
571 return err;
572}
573
574/*
575 * Callback functions that enumerate, mark, and collect dirty blocks
576 */
577static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
578 struct buffer_head *bh, struct inode *inode)
579{
580 int err;
581
582 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
583 if (err < 0)
584 return err;
585
586 err = nilfs_segctor_add_file_block(sci, bh, inode,
587 sizeof(struct nilfs_binfo_v));
588 if (!err)
589 sci->sc_datablk_cnt++;
590 return err;
591}
592
593static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
594 struct buffer_head *bh,
595 struct inode *inode)
596{
597 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
598}
599
600static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
601 struct buffer_head *bh,
602 struct inode *inode)
603{
604 WARN_ON(!buffer_dirty(bh));
605 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
606}
607
608static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
609 struct nilfs_segsum_pointer *ssp,
610 union nilfs_binfo *binfo)
611{
612 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
613 sci, ssp, sizeof(*binfo_v));
614 *binfo_v = binfo->bi_v;
615}
616
617static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
618 struct nilfs_segsum_pointer *ssp,
619 union nilfs_binfo *binfo)
620{
621 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
622 sci, ssp, sizeof(*vblocknr));
623 *vblocknr = binfo->bi_v.bi_vblocknr;
624}
625
626static const struct nilfs_sc_operations nilfs_sc_file_ops = {
627 .collect_data = nilfs_collect_file_data,
628 .collect_node = nilfs_collect_file_node,
629 .collect_bmap = nilfs_collect_file_bmap,
630 .write_data_binfo = nilfs_write_file_data_binfo,
631 .write_node_binfo = nilfs_write_file_node_binfo,
632};
633
634static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
635 struct buffer_head *bh, struct inode *inode)
636{
637 int err;
638
639 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
640 if (err < 0)
641 return err;
642
643 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
644 if (!err)
645 sci->sc_datablk_cnt++;
646 return err;
647}
648
649static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
650 struct buffer_head *bh, struct inode *inode)
651{
652 WARN_ON(!buffer_dirty(bh));
653 return nilfs_segctor_add_file_block(sci, bh, inode,
654 sizeof(struct nilfs_binfo_dat));
655}
656
657static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
658 struct nilfs_segsum_pointer *ssp,
659 union nilfs_binfo *binfo)
660{
661 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
662 sizeof(*blkoff));
663 *blkoff = binfo->bi_dat.bi_blkoff;
664}
665
666static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
667 struct nilfs_segsum_pointer *ssp,
668 union nilfs_binfo *binfo)
669{
670 struct nilfs_binfo_dat *binfo_dat =
671 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
672 *binfo_dat = binfo->bi_dat;
673}
674
675static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
676 .collect_data = nilfs_collect_dat_data,
677 .collect_node = nilfs_collect_file_node,
678 .collect_bmap = nilfs_collect_dat_bmap,
679 .write_data_binfo = nilfs_write_dat_data_binfo,
680 .write_node_binfo = nilfs_write_dat_node_binfo,
681};
682
683static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
684 .collect_data = nilfs_collect_file_data,
685 .collect_node = NULL,
686 .collect_bmap = NULL,
687 .write_data_binfo = nilfs_write_file_data_binfo,
688 .write_node_binfo = NULL,
689};
690
691static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
692 struct list_head *listp,
693 size_t nlimit,
694 loff_t start, loff_t end)
695{
696 struct address_space *mapping = inode->i_mapping;
697 struct pagevec pvec;
698 pgoff_t index = 0, last = ULONG_MAX;
699 size_t ndirties = 0;
700 int i;
701
702 if (unlikely(start != 0 || end != LLONG_MAX)) {
703 /*
704 * A valid range is given for sync-ing data pages. The
705 * range is rounded to per-page; extra dirty buffers
706 * may be included if blocksize < pagesize.
707 */
708 index = start >> PAGE_SHIFT;
709 last = end >> PAGE_SHIFT;
710 }
711 pagevec_init(&pvec);
712 repeat:
713 if (unlikely(index > last) ||
714 !pagevec_lookup_range_tag(&pvec, mapping, &index, last,
715 PAGECACHE_TAG_DIRTY))
716 return ndirties;
717
718 for (i = 0; i < pagevec_count(&pvec); i++) {
719 struct buffer_head *bh, *head;
720 struct page *page = pvec.pages[i];
721
722 lock_page(page);
723 if (!page_has_buffers(page))
724 create_empty_buffers(page, i_blocksize(inode), 0);
725 unlock_page(page);
726
727 bh = head = page_buffers(page);
728 do {
729 if (!buffer_dirty(bh) || buffer_async_write(bh))
730 continue;
731 get_bh(bh);
732 list_add_tail(&bh->b_assoc_buffers, listp);
733 ndirties++;
734 if (unlikely(ndirties >= nlimit)) {
735 pagevec_release(&pvec);
736 cond_resched();
737 return ndirties;
738 }
739 } while (bh = bh->b_this_page, bh != head);
740 }
741 pagevec_release(&pvec);
742 cond_resched();
743 goto repeat;
744}
745
746static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
747 struct list_head *listp)
748{
749 struct nilfs_inode_info *ii = NILFS_I(inode);
750 struct address_space *mapping = &ii->i_btnode_cache;
751 struct pagevec pvec;
752 struct buffer_head *bh, *head;
753 unsigned int i;
754 pgoff_t index = 0;
755
756 pagevec_init(&pvec);
757
758 while (pagevec_lookup_tag(&pvec, mapping, &index,
759 PAGECACHE_TAG_DIRTY)) {
760 for (i = 0; i < pagevec_count(&pvec); i++) {
761 bh = head = page_buffers(pvec.pages[i]);
762 do {
763 if (buffer_dirty(bh) &&
764 !buffer_async_write(bh)) {
765 get_bh(bh);
766 list_add_tail(&bh->b_assoc_buffers,
767 listp);
768 }
769 bh = bh->b_this_page;
770 } while (bh != head);
771 }
772 pagevec_release(&pvec);
773 cond_resched();
774 }
775}
776
777static void nilfs_dispose_list(struct the_nilfs *nilfs,
778 struct list_head *head, int force)
779{
780 struct nilfs_inode_info *ii, *n;
781 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
782 unsigned int nv = 0;
783
784 while (!list_empty(head)) {
785 spin_lock(&nilfs->ns_inode_lock);
786 list_for_each_entry_safe(ii, n, head, i_dirty) {
787 list_del_init(&ii->i_dirty);
788 if (force) {
789 if (unlikely(ii->i_bh)) {
790 brelse(ii->i_bh);
791 ii->i_bh = NULL;
792 }
793 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
794 set_bit(NILFS_I_QUEUED, &ii->i_state);
795 list_add_tail(&ii->i_dirty,
796 &nilfs->ns_dirty_files);
797 continue;
798 }
799 ivec[nv++] = ii;
800 if (nv == SC_N_INODEVEC)
801 break;
802 }
803 spin_unlock(&nilfs->ns_inode_lock);
804
805 for (pii = ivec; nv > 0; pii++, nv--)
806 iput(&(*pii)->vfs_inode);
807 }
808}
809
810static void nilfs_iput_work_func(struct work_struct *work)
811{
812 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
813 sc_iput_work);
814 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
815
816 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
817}
818
819static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
820 struct nilfs_root *root)
821{
822 int ret = 0;
823
824 if (nilfs_mdt_fetch_dirty(root->ifile))
825 ret++;
826 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
827 ret++;
828 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
829 ret++;
830 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
831 ret++;
832 return ret;
833}
834
835static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
836{
837 return list_empty(&sci->sc_dirty_files) &&
838 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
839 sci->sc_nfreesegs == 0 &&
840 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
841}
842
843static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
844{
845 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
846 int ret = 0;
847
848 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
849 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
850
851 spin_lock(&nilfs->ns_inode_lock);
852 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
853 ret++;
854
855 spin_unlock(&nilfs->ns_inode_lock);
856 return ret;
857}
858
859static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
860{
861 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
862
863 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
864 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
865 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
866 nilfs_mdt_clear_dirty(nilfs->ns_dat);
867}
868
869static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
870{
871 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
872 struct buffer_head *bh_cp;
873 struct nilfs_checkpoint *raw_cp;
874 int err;
875
876 /* XXX: this interface will be changed */
877 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
878 &raw_cp, &bh_cp);
879 if (likely(!err)) {
880 /*
881 * The following code is duplicated with cpfile. But, it is
882 * needed to collect the checkpoint even if it was not newly
883 * created.
884 */
885 mark_buffer_dirty(bh_cp);
886 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
887 nilfs_cpfile_put_checkpoint(
888 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
889 } else
890 WARN_ON(err == -EINVAL || err == -ENOENT);
891
892 return err;
893}
894
895static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
896{
897 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
898 struct buffer_head *bh_cp;
899 struct nilfs_checkpoint *raw_cp;
900 int err;
901
902 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
903 &raw_cp, &bh_cp);
904 if (unlikely(err)) {
905 WARN_ON(err == -EINVAL || err == -ENOENT);
906 goto failed_ibh;
907 }
908 raw_cp->cp_snapshot_list.ssl_next = 0;
909 raw_cp->cp_snapshot_list.ssl_prev = 0;
910 raw_cp->cp_inodes_count =
911 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
912 raw_cp->cp_blocks_count =
913 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
914 raw_cp->cp_nblk_inc =
915 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
916 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
917 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
918
919 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
920 nilfs_checkpoint_clear_minor(raw_cp);
921 else
922 nilfs_checkpoint_set_minor(raw_cp);
923
924 nilfs_write_inode_common(sci->sc_root->ifile,
925 &raw_cp->cp_ifile_inode, 1);
926 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
927 return 0;
928
929 failed_ibh:
930 return err;
931}
932
933static void nilfs_fill_in_file_bmap(struct inode *ifile,
934 struct nilfs_inode_info *ii)
935
936{
937 struct buffer_head *ibh;
938 struct nilfs_inode *raw_inode;
939
940 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
941 ibh = ii->i_bh;
942 BUG_ON(!ibh);
943 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
944 ibh);
945 nilfs_bmap_write(ii->i_bmap, raw_inode);
946 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
947 }
948}
949
950static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
951{
952 struct nilfs_inode_info *ii;
953
954 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
955 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
956 set_bit(NILFS_I_COLLECTED, &ii->i_state);
957 }
958}
959
960static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
961 struct the_nilfs *nilfs)
962{
963 struct buffer_head *bh_sr;
964 struct nilfs_super_root *raw_sr;
965 unsigned int isz, srsz;
966
967 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
968 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
969 isz = nilfs->ns_inode_size;
970 srsz = NILFS_SR_BYTES(isz);
971
972 raw_sr->sr_bytes = cpu_to_le16(srsz);
973 raw_sr->sr_nongc_ctime
974 = cpu_to_le64(nilfs_doing_gc() ?
975 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
976 raw_sr->sr_flags = 0;
977
978 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
979 NILFS_SR_DAT_OFFSET(isz), 1);
980 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
981 NILFS_SR_CPFILE_OFFSET(isz), 1);
982 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
983 NILFS_SR_SUFILE_OFFSET(isz), 1);
984 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
985}
986
987static void nilfs_redirty_inodes(struct list_head *head)
988{
989 struct nilfs_inode_info *ii;
990
991 list_for_each_entry(ii, head, i_dirty) {
992 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
993 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
994 }
995}
996
997static void nilfs_drop_collected_inodes(struct list_head *head)
998{
999 struct nilfs_inode_info *ii;
1000
1001 list_for_each_entry(ii, head, i_dirty) {
1002 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
1003 continue;
1004
1005 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
1006 set_bit(NILFS_I_UPDATED, &ii->i_state);
1007 }
1008}
1009
1010static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1011 struct inode *inode,
1012 struct list_head *listp,
1013 int (*collect)(struct nilfs_sc_info *,
1014 struct buffer_head *,
1015 struct inode *))
1016{
1017 struct buffer_head *bh, *n;
1018 int err = 0;
1019
1020 if (collect) {
1021 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1022 list_del_init(&bh->b_assoc_buffers);
1023 err = collect(sci, bh, inode);
1024 brelse(bh);
1025 if (unlikely(err))
1026 goto dispose_buffers;
1027 }
1028 return 0;
1029 }
1030
1031 dispose_buffers:
1032 while (!list_empty(listp)) {
1033 bh = list_first_entry(listp, struct buffer_head,
1034 b_assoc_buffers);
1035 list_del_init(&bh->b_assoc_buffers);
1036 brelse(bh);
1037 }
1038 return err;
1039}
1040
1041static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1042{
1043 /* Remaining number of blocks within segment buffer */
1044 return sci->sc_segbuf_nblocks -
1045 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1046}
1047
1048static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1049 struct inode *inode,
1050 const struct nilfs_sc_operations *sc_ops)
1051{
1052 LIST_HEAD(data_buffers);
1053 LIST_HEAD(node_buffers);
1054 int err;
1055
1056 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1057 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1058
1059 n = nilfs_lookup_dirty_data_buffers(
1060 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1061 if (n > rest) {
1062 err = nilfs_segctor_apply_buffers(
1063 sci, inode, &data_buffers,
1064 sc_ops->collect_data);
1065 BUG_ON(!err); /* always receive -E2BIG or true error */
1066 goto break_or_fail;
1067 }
1068 }
1069 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1070
1071 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1072 err = nilfs_segctor_apply_buffers(
1073 sci, inode, &data_buffers, sc_ops->collect_data);
1074 if (unlikely(err)) {
1075 /* dispose node list */
1076 nilfs_segctor_apply_buffers(
1077 sci, inode, &node_buffers, NULL);
1078 goto break_or_fail;
1079 }
1080 sci->sc_stage.flags |= NILFS_CF_NODE;
1081 }
1082 /* Collect node */
1083 err = nilfs_segctor_apply_buffers(
1084 sci, inode, &node_buffers, sc_ops->collect_node);
1085 if (unlikely(err))
1086 goto break_or_fail;
1087
1088 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1089 err = nilfs_segctor_apply_buffers(
1090 sci, inode, &node_buffers, sc_ops->collect_bmap);
1091 if (unlikely(err))
1092 goto break_or_fail;
1093
1094 nilfs_segctor_end_finfo(sci, inode);
1095 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1096
1097 break_or_fail:
1098 return err;
1099}
1100
1101static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1102 struct inode *inode)
1103{
1104 LIST_HEAD(data_buffers);
1105 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1106 int err;
1107
1108 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1109 sci->sc_dsync_start,
1110 sci->sc_dsync_end);
1111
1112 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1113 nilfs_collect_file_data);
1114 if (!err) {
1115 nilfs_segctor_end_finfo(sci, inode);
1116 BUG_ON(n > rest);
1117 /* always receive -E2BIG or true error if n > rest */
1118 }
1119 return err;
1120}
1121
1122static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1123{
1124 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1125 struct list_head *head;
1126 struct nilfs_inode_info *ii;
1127 size_t ndone;
1128 int err = 0;
1129
1130 switch (nilfs_sc_cstage_get(sci)) {
1131 case NILFS_ST_INIT:
1132 /* Pre-processes */
1133 sci->sc_stage.flags = 0;
1134
1135 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1136 sci->sc_nblk_inc = 0;
1137 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1138 if (mode == SC_LSEG_DSYNC) {
1139 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1140 goto dsync_mode;
1141 }
1142 }
1143
1144 sci->sc_stage.dirty_file_ptr = NULL;
1145 sci->sc_stage.gc_inode_ptr = NULL;
1146 if (mode == SC_FLUSH_DAT) {
1147 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1148 goto dat_stage;
1149 }
1150 nilfs_sc_cstage_inc(sci); /* Fall through */
1151 case NILFS_ST_GC:
1152 if (nilfs_doing_gc()) {
1153 head = &sci->sc_gc_inodes;
1154 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1155 head, i_dirty);
1156 list_for_each_entry_continue(ii, head, i_dirty) {
1157 err = nilfs_segctor_scan_file(
1158 sci, &ii->vfs_inode,
1159 &nilfs_sc_file_ops);
1160 if (unlikely(err)) {
1161 sci->sc_stage.gc_inode_ptr = list_entry(
1162 ii->i_dirty.prev,
1163 struct nilfs_inode_info,
1164 i_dirty);
1165 goto break_or_fail;
1166 }
1167 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1168 }
1169 sci->sc_stage.gc_inode_ptr = NULL;
1170 }
1171 nilfs_sc_cstage_inc(sci); /* Fall through */
1172 case NILFS_ST_FILE:
1173 head = &sci->sc_dirty_files;
1174 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1175 i_dirty);
1176 list_for_each_entry_continue(ii, head, i_dirty) {
1177 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1178
1179 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1180 &nilfs_sc_file_ops);
1181 if (unlikely(err)) {
1182 sci->sc_stage.dirty_file_ptr =
1183 list_entry(ii->i_dirty.prev,
1184 struct nilfs_inode_info,
1185 i_dirty);
1186 goto break_or_fail;
1187 }
1188 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1189 /* XXX: required ? */
1190 }
1191 sci->sc_stage.dirty_file_ptr = NULL;
1192 if (mode == SC_FLUSH_FILE) {
1193 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1194 return 0;
1195 }
1196 nilfs_sc_cstage_inc(sci);
1197 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1198 /* Fall through */
1199 case NILFS_ST_IFILE:
1200 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1201 &nilfs_sc_file_ops);
1202 if (unlikely(err))
1203 break;
1204 nilfs_sc_cstage_inc(sci);
1205 /* Creating a checkpoint */
1206 err = nilfs_segctor_create_checkpoint(sci);
1207 if (unlikely(err))
1208 break;
1209 /* Fall through */
1210 case NILFS_ST_CPFILE:
1211 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1212 &nilfs_sc_file_ops);
1213 if (unlikely(err))
1214 break;
1215 nilfs_sc_cstage_inc(sci); /* Fall through */
1216 case NILFS_ST_SUFILE:
1217 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1218 sci->sc_nfreesegs, &ndone);
1219 if (unlikely(err)) {
1220 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1221 sci->sc_freesegs, ndone,
1222 NULL);
1223 break;
1224 }
1225 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1226
1227 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1228 &nilfs_sc_file_ops);
1229 if (unlikely(err))
1230 break;
1231 nilfs_sc_cstage_inc(sci); /* Fall through */
1232 case NILFS_ST_DAT:
1233 dat_stage:
1234 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1235 &nilfs_sc_dat_ops);
1236 if (unlikely(err))
1237 break;
1238 if (mode == SC_FLUSH_DAT) {
1239 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1240 return 0;
1241 }
1242 nilfs_sc_cstage_inc(sci); /* Fall through */
1243 case NILFS_ST_SR:
1244 if (mode == SC_LSEG_SR) {
1245 /* Appending a super root */
1246 err = nilfs_segctor_add_super_root(sci);
1247 if (unlikely(err))
1248 break;
1249 }
1250 /* End of a logical segment */
1251 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1252 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1253 return 0;
1254 case NILFS_ST_DSYNC:
1255 dsync_mode:
1256 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1257 ii = sci->sc_dsync_inode;
1258 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1259 break;
1260
1261 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1262 if (unlikely(err))
1263 break;
1264 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1265 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1266 return 0;
1267 case NILFS_ST_DONE:
1268 return 0;
1269 default:
1270 BUG();
1271 }
1272
1273 break_or_fail:
1274 return err;
1275}
1276
1277/**
1278 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1279 * @sci: nilfs_sc_info
1280 * @nilfs: nilfs object
1281 */
1282static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1283 struct the_nilfs *nilfs)
1284{
1285 struct nilfs_segment_buffer *segbuf, *prev;
1286 __u64 nextnum;
1287 int err, alloc = 0;
1288
1289 segbuf = nilfs_segbuf_new(sci->sc_super);
1290 if (unlikely(!segbuf))
1291 return -ENOMEM;
1292
1293 if (list_empty(&sci->sc_write_logs)) {
1294 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1295 nilfs->ns_pseg_offset, nilfs);
1296 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1297 nilfs_shift_to_next_segment(nilfs);
1298 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1299 }
1300
1301 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1302 nextnum = nilfs->ns_nextnum;
1303
1304 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1305 /* Start from the head of a new full segment */
1306 alloc++;
1307 } else {
1308 /* Continue logs */
1309 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1310 nilfs_segbuf_map_cont(segbuf, prev);
1311 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1312 nextnum = prev->sb_nextnum;
1313
1314 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1315 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1316 segbuf->sb_sum.seg_seq++;
1317 alloc++;
1318 }
1319 }
1320
1321 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1322 if (err)
1323 goto failed;
1324
1325 if (alloc) {
1326 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1327 if (err)
1328 goto failed;
1329 }
1330 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1331
1332 BUG_ON(!list_empty(&sci->sc_segbufs));
1333 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1334 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1335 return 0;
1336
1337 failed:
1338 nilfs_segbuf_free(segbuf);
1339 return err;
1340}
1341
1342static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1343 struct the_nilfs *nilfs, int nadd)
1344{
1345 struct nilfs_segment_buffer *segbuf, *prev;
1346 struct inode *sufile = nilfs->ns_sufile;
1347 __u64 nextnextnum;
1348 LIST_HEAD(list);
1349 int err, ret, i;
1350
1351 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1352 /*
1353 * Since the segment specified with nextnum might be allocated during
1354 * the previous construction, the buffer including its segusage may
1355 * not be dirty. The following call ensures that the buffer is dirty
1356 * and will pin the buffer on memory until the sufile is written.
1357 */
1358 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1359 if (unlikely(err))
1360 return err;
1361
1362 for (i = 0; i < nadd; i++) {
1363 /* extend segment info */
1364 err = -ENOMEM;
1365 segbuf = nilfs_segbuf_new(sci->sc_super);
1366 if (unlikely(!segbuf))
1367 goto failed;
1368
1369 /* map this buffer to region of segment on-disk */
1370 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1371 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1372
1373 /* allocate the next next full segment */
1374 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1375 if (unlikely(err))
1376 goto failed_segbuf;
1377
1378 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1379 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1380
1381 list_add_tail(&segbuf->sb_list, &list);
1382 prev = segbuf;
1383 }
1384 list_splice_tail(&list, &sci->sc_segbufs);
1385 return 0;
1386
1387 failed_segbuf:
1388 nilfs_segbuf_free(segbuf);
1389 failed:
1390 list_for_each_entry(segbuf, &list, sb_list) {
1391 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1392 WARN_ON(ret); /* never fails */
1393 }
1394 nilfs_destroy_logs(&list);
1395 return err;
1396}
1397
1398static void nilfs_free_incomplete_logs(struct list_head *logs,
1399 struct the_nilfs *nilfs)
1400{
1401 struct nilfs_segment_buffer *segbuf, *prev;
1402 struct inode *sufile = nilfs->ns_sufile;
1403 int ret;
1404
1405 segbuf = NILFS_FIRST_SEGBUF(logs);
1406 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1407 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1408 WARN_ON(ret); /* never fails */
1409 }
1410 if (atomic_read(&segbuf->sb_err)) {
1411 /* Case 1: The first segment failed */
1412 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1413 /*
1414 * Case 1a: Partial segment appended into an existing
1415 * segment
1416 */
1417 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1418 segbuf->sb_fseg_end);
1419 else /* Case 1b: New full segment */
1420 set_nilfs_discontinued(nilfs);
1421 }
1422
1423 prev = segbuf;
1424 list_for_each_entry_continue(segbuf, logs, sb_list) {
1425 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1426 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1427 WARN_ON(ret); /* never fails */
1428 }
1429 if (atomic_read(&segbuf->sb_err) &&
1430 segbuf->sb_segnum != nilfs->ns_nextnum)
1431 /* Case 2: extended segment (!= next) failed */
1432 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1433 prev = segbuf;
1434 }
1435}
1436
1437static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1438 struct inode *sufile)
1439{
1440 struct nilfs_segment_buffer *segbuf;
1441 unsigned long live_blocks;
1442 int ret;
1443
1444 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1445 live_blocks = segbuf->sb_sum.nblocks +
1446 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1447 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1448 live_blocks,
1449 sci->sc_seg_ctime);
1450 WARN_ON(ret); /* always succeed because the segusage is dirty */
1451 }
1452}
1453
1454static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1455{
1456 struct nilfs_segment_buffer *segbuf;
1457 int ret;
1458
1459 segbuf = NILFS_FIRST_SEGBUF(logs);
1460 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1461 segbuf->sb_pseg_start -
1462 segbuf->sb_fseg_start, 0);
1463 WARN_ON(ret); /* always succeed because the segusage is dirty */
1464
1465 list_for_each_entry_continue(segbuf, logs, sb_list) {
1466 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1467 0, 0);
1468 WARN_ON(ret); /* always succeed */
1469 }
1470}
1471
1472static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1473 struct nilfs_segment_buffer *last,
1474 struct inode *sufile)
1475{
1476 struct nilfs_segment_buffer *segbuf = last;
1477 int ret;
1478
1479 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1480 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1481 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1482 WARN_ON(ret);
1483 }
1484 nilfs_truncate_logs(&sci->sc_segbufs, last);
1485}
1486
1487
1488static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1489 struct the_nilfs *nilfs, int mode)
1490{
1491 struct nilfs_cstage prev_stage = sci->sc_stage;
1492 int err, nadd = 1;
1493
1494 /* Collection retry loop */
1495 for (;;) {
1496 sci->sc_nblk_this_inc = 0;
1497 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1498
1499 err = nilfs_segctor_reset_segment_buffer(sci);
1500 if (unlikely(err))
1501 goto failed;
1502
1503 err = nilfs_segctor_collect_blocks(sci, mode);
1504 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1505 if (!err)
1506 break;
1507
1508 if (unlikely(err != -E2BIG))
1509 goto failed;
1510
1511 /* The current segment is filled up */
1512 if (mode != SC_LSEG_SR ||
1513 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1514 break;
1515
1516 nilfs_clear_logs(&sci->sc_segbufs);
1517
1518 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1519 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1520 sci->sc_freesegs,
1521 sci->sc_nfreesegs,
1522 NULL);
1523 WARN_ON(err); /* do not happen */
1524 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1525 }
1526
1527 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1528 if (unlikely(err))
1529 return err;
1530
1531 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1532 sci->sc_stage = prev_stage;
1533 }
1534 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1535 return 0;
1536
1537 failed:
1538 return err;
1539}
1540
1541static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1542 struct buffer_head *new_bh)
1543{
1544 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1545
1546 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1547 /* The caller must release old_bh */
1548}
1549
1550static int
1551nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1552 struct nilfs_segment_buffer *segbuf,
1553 int mode)
1554{
1555 struct inode *inode = NULL;
1556 sector_t blocknr;
1557 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1558 unsigned long nblocks = 0, ndatablk = 0;
1559 const struct nilfs_sc_operations *sc_op = NULL;
1560 struct nilfs_segsum_pointer ssp;
1561 struct nilfs_finfo *finfo = NULL;
1562 union nilfs_binfo binfo;
1563 struct buffer_head *bh, *bh_org;
1564 ino_t ino = 0;
1565 int err = 0;
1566
1567 if (!nfinfo)
1568 goto out;
1569
1570 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1571 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1572 ssp.offset = sizeof(struct nilfs_segment_summary);
1573
1574 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1575 if (bh == segbuf->sb_super_root)
1576 break;
1577 if (!finfo) {
1578 finfo = nilfs_segctor_map_segsum_entry(
1579 sci, &ssp, sizeof(*finfo));
1580 ino = le64_to_cpu(finfo->fi_ino);
1581 nblocks = le32_to_cpu(finfo->fi_nblocks);
1582 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1583
1584 inode = bh->b_page->mapping->host;
1585
1586 if (mode == SC_LSEG_DSYNC)
1587 sc_op = &nilfs_sc_dsync_ops;
1588 else if (ino == NILFS_DAT_INO)
1589 sc_op = &nilfs_sc_dat_ops;
1590 else /* file blocks */
1591 sc_op = &nilfs_sc_file_ops;
1592 }
1593 bh_org = bh;
1594 get_bh(bh_org);
1595 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1596 &binfo);
1597 if (bh != bh_org)
1598 nilfs_list_replace_buffer(bh_org, bh);
1599 brelse(bh_org);
1600 if (unlikely(err))
1601 goto failed_bmap;
1602
1603 if (ndatablk > 0)
1604 sc_op->write_data_binfo(sci, &ssp, &binfo);
1605 else
1606 sc_op->write_node_binfo(sci, &ssp, &binfo);
1607
1608 blocknr++;
1609 if (--nblocks == 0) {
1610 finfo = NULL;
1611 if (--nfinfo == 0)
1612 break;
1613 } else if (ndatablk > 0)
1614 ndatablk--;
1615 }
1616 out:
1617 return 0;
1618
1619 failed_bmap:
1620 return err;
1621}
1622
1623static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1624{
1625 struct nilfs_segment_buffer *segbuf;
1626 int err;
1627
1628 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1629 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1630 if (unlikely(err))
1631 return err;
1632 nilfs_segbuf_fill_in_segsum(segbuf);
1633 }
1634 return 0;
1635}
1636
1637static void nilfs_begin_page_io(struct page *page)
1638{
1639 if (!page || PageWriteback(page))
1640 /*
1641 * For split b-tree node pages, this function may be called
1642 * twice. We ignore the 2nd or later calls by this check.
1643 */
1644 return;
1645
1646 lock_page(page);
1647 clear_page_dirty_for_io(page);
1648 set_page_writeback(page);
1649 unlock_page(page);
1650}
1651
1652static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1653{
1654 struct nilfs_segment_buffer *segbuf;
1655 struct page *bd_page = NULL, *fs_page = NULL;
1656
1657 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1658 struct buffer_head *bh;
1659
1660 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1661 b_assoc_buffers) {
1662 if (bh->b_page != bd_page) {
1663 if (bd_page) {
1664 lock_page(bd_page);
1665 clear_page_dirty_for_io(bd_page);
1666 set_page_writeback(bd_page);
1667 unlock_page(bd_page);
1668 }
1669 bd_page = bh->b_page;
1670 }
1671 }
1672
1673 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1674 b_assoc_buffers) {
1675 set_buffer_async_write(bh);
1676 if (bh == segbuf->sb_super_root) {
1677 if (bh->b_page != bd_page) {
1678 lock_page(bd_page);
1679 clear_page_dirty_for_io(bd_page);
1680 set_page_writeback(bd_page);
1681 unlock_page(bd_page);
1682 bd_page = bh->b_page;
1683 }
1684 break;
1685 }
1686 if (bh->b_page != fs_page) {
1687 nilfs_begin_page_io(fs_page);
1688 fs_page = bh->b_page;
1689 }
1690 }
1691 }
1692 if (bd_page) {
1693 lock_page(bd_page);
1694 clear_page_dirty_for_io(bd_page);
1695 set_page_writeback(bd_page);
1696 unlock_page(bd_page);
1697 }
1698 nilfs_begin_page_io(fs_page);
1699}
1700
1701static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1702 struct the_nilfs *nilfs)
1703{
1704 int ret;
1705
1706 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1707 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1708 return ret;
1709}
1710
1711static void nilfs_end_page_io(struct page *page, int err)
1712{
1713 if (!page)
1714 return;
1715
1716 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1717 /*
1718 * For b-tree node pages, this function may be called twice
1719 * or more because they might be split in a segment.
1720 */
1721 if (PageDirty(page)) {
1722 /*
1723 * For pages holding split b-tree node buffers, dirty
1724 * flag on the buffers may be cleared discretely.
1725 * In that case, the page is once redirtied for
1726 * remaining buffers, and it must be cancelled if
1727 * all the buffers get cleaned later.
1728 */
1729 lock_page(page);
1730 if (nilfs_page_buffers_clean(page))
1731 __nilfs_clear_page_dirty(page);
1732 unlock_page(page);
1733 }
1734 return;
1735 }
1736
1737 if (!err) {
1738 if (!nilfs_page_buffers_clean(page))
1739 __set_page_dirty_nobuffers(page);
1740 ClearPageError(page);
1741 } else {
1742 __set_page_dirty_nobuffers(page);
1743 SetPageError(page);
1744 }
1745
1746 end_page_writeback(page);
1747}
1748
1749static void nilfs_abort_logs(struct list_head *logs, int err)
1750{
1751 struct nilfs_segment_buffer *segbuf;
1752 struct page *bd_page = NULL, *fs_page = NULL;
1753 struct buffer_head *bh;
1754
1755 if (list_empty(logs))
1756 return;
1757
1758 list_for_each_entry(segbuf, logs, sb_list) {
1759 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1760 b_assoc_buffers) {
1761 if (bh->b_page != bd_page) {
1762 if (bd_page)
1763 end_page_writeback(bd_page);
1764 bd_page = bh->b_page;
1765 }
1766 }
1767
1768 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1769 b_assoc_buffers) {
1770 clear_buffer_async_write(bh);
1771 if (bh == segbuf->sb_super_root) {
1772 if (bh->b_page != bd_page) {
1773 end_page_writeback(bd_page);
1774 bd_page = bh->b_page;
1775 }
1776 break;
1777 }
1778 if (bh->b_page != fs_page) {
1779 nilfs_end_page_io(fs_page, err);
1780 fs_page = bh->b_page;
1781 }
1782 }
1783 }
1784 if (bd_page)
1785 end_page_writeback(bd_page);
1786
1787 nilfs_end_page_io(fs_page, err);
1788}
1789
1790static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1791 struct the_nilfs *nilfs, int err)
1792{
1793 LIST_HEAD(logs);
1794 int ret;
1795
1796 list_splice_tail_init(&sci->sc_write_logs, &logs);
1797 ret = nilfs_wait_on_logs(&logs);
1798 nilfs_abort_logs(&logs, ret ? : err);
1799
1800 list_splice_tail_init(&sci->sc_segbufs, &logs);
1801 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1802 nilfs_free_incomplete_logs(&logs, nilfs);
1803
1804 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1805 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1806 sci->sc_freesegs,
1807 sci->sc_nfreesegs,
1808 NULL);
1809 WARN_ON(ret); /* do not happen */
1810 }
1811
1812 nilfs_destroy_logs(&logs);
1813}
1814
1815static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1816 struct nilfs_segment_buffer *segbuf)
1817{
1818 nilfs->ns_segnum = segbuf->sb_segnum;
1819 nilfs->ns_nextnum = segbuf->sb_nextnum;
1820 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1821 + segbuf->sb_sum.nblocks;
1822 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1823 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1824}
1825
1826static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1827{
1828 struct nilfs_segment_buffer *segbuf;
1829 struct page *bd_page = NULL, *fs_page = NULL;
1830 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1831 int update_sr = false;
1832
1833 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1834 struct buffer_head *bh;
1835
1836 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1837 b_assoc_buffers) {
1838 set_buffer_uptodate(bh);
1839 clear_buffer_dirty(bh);
1840 if (bh->b_page != bd_page) {
1841 if (bd_page)
1842 end_page_writeback(bd_page);
1843 bd_page = bh->b_page;
1844 }
1845 }
1846 /*
1847 * We assume that the buffers which belong to the same page
1848 * continue over the buffer list.
1849 * Under this assumption, the last BHs of pages is
1850 * identifiable by the discontinuity of bh->b_page
1851 * (page != fs_page).
1852 *
1853 * For B-tree node blocks, however, this assumption is not
1854 * guaranteed. The cleanup code of B-tree node pages needs
1855 * special care.
1856 */
1857 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1858 b_assoc_buffers) {
1859 const unsigned long set_bits = BIT(BH_Uptodate);
1860 const unsigned long clear_bits =
1861 (BIT(BH_Dirty) | BIT(BH_Async_Write) |
1862 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) |
1863 BIT(BH_NILFS_Redirected));
1864
1865 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1866 if (bh == segbuf->sb_super_root) {
1867 if (bh->b_page != bd_page) {
1868 end_page_writeback(bd_page);
1869 bd_page = bh->b_page;
1870 }
1871 update_sr = true;
1872 break;
1873 }
1874 if (bh->b_page != fs_page) {
1875 nilfs_end_page_io(fs_page, 0);
1876 fs_page = bh->b_page;
1877 }
1878 }
1879
1880 if (!nilfs_segbuf_simplex(segbuf)) {
1881 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1882 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1883 sci->sc_lseg_stime = jiffies;
1884 }
1885 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1886 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1887 }
1888 }
1889 /*
1890 * Since pages may continue over multiple segment buffers,
1891 * end of the last page must be checked outside of the loop.
1892 */
1893 if (bd_page)
1894 end_page_writeback(bd_page);
1895
1896 nilfs_end_page_io(fs_page, 0);
1897
1898 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1899
1900 if (nilfs_doing_gc())
1901 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1902 else
1903 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1904
1905 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1906
1907 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1908 nilfs_set_next_segment(nilfs, segbuf);
1909
1910 if (update_sr) {
1911 nilfs->ns_flushed_device = 0;
1912 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1913 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1914
1915 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1916 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1917 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1918 nilfs_segctor_clear_metadata_dirty(sci);
1919 } else
1920 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1921}
1922
1923static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1924{
1925 int ret;
1926
1927 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1928 if (!ret) {
1929 nilfs_segctor_complete_write(sci);
1930 nilfs_destroy_logs(&sci->sc_write_logs);
1931 }
1932 return ret;
1933}
1934
1935static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1936 struct the_nilfs *nilfs)
1937{
1938 struct nilfs_inode_info *ii, *n;
1939 struct inode *ifile = sci->sc_root->ifile;
1940
1941 spin_lock(&nilfs->ns_inode_lock);
1942 retry:
1943 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1944 if (!ii->i_bh) {
1945 struct buffer_head *ibh;
1946 int err;
1947
1948 spin_unlock(&nilfs->ns_inode_lock);
1949 err = nilfs_ifile_get_inode_block(
1950 ifile, ii->vfs_inode.i_ino, &ibh);
1951 if (unlikely(err)) {
1952 nilfs_msg(sci->sc_super, KERN_WARNING,
1953 "log writer: error %d getting inode block (ino=%lu)",
1954 err, ii->vfs_inode.i_ino);
1955 return err;
1956 }
1957 spin_lock(&nilfs->ns_inode_lock);
1958 if (likely(!ii->i_bh))
1959 ii->i_bh = ibh;
1960 else
1961 brelse(ibh);
1962 goto retry;
1963 }
1964
1965 // Always redirty the buffer to avoid race condition
1966 mark_buffer_dirty(ii->i_bh);
1967 nilfs_mdt_mark_dirty(ifile);
1968
1969 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1970 set_bit(NILFS_I_BUSY, &ii->i_state);
1971 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1972 }
1973 spin_unlock(&nilfs->ns_inode_lock);
1974
1975 return 0;
1976}
1977
1978static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1979 struct the_nilfs *nilfs)
1980{
1981 struct nilfs_inode_info *ii, *n;
1982 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
1983 int defer_iput = false;
1984
1985 spin_lock(&nilfs->ns_inode_lock);
1986 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1987 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1988 test_bit(NILFS_I_DIRTY, &ii->i_state))
1989 continue;
1990
1991 clear_bit(NILFS_I_BUSY, &ii->i_state);
1992 brelse(ii->i_bh);
1993 ii->i_bh = NULL;
1994 list_del_init(&ii->i_dirty);
1995 if (!ii->vfs_inode.i_nlink || during_mount) {
1996 /*
1997 * Defer calling iput() to avoid deadlocks if
1998 * i_nlink == 0 or mount is not yet finished.
1999 */
2000 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
2001 defer_iput = true;
2002 } else {
2003 spin_unlock(&nilfs->ns_inode_lock);
2004 iput(&ii->vfs_inode);
2005 spin_lock(&nilfs->ns_inode_lock);
2006 }
2007 }
2008 spin_unlock(&nilfs->ns_inode_lock);
2009
2010 if (defer_iput)
2011 schedule_work(&sci->sc_iput_work);
2012}
2013
2014/*
2015 * Main procedure of segment constructor
2016 */
2017static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2018{
2019 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2020 int err;
2021
2022 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2023 sci->sc_cno = nilfs->ns_cno;
2024
2025 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2026 if (unlikely(err))
2027 goto out;
2028
2029 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2030 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2031
2032 if (nilfs_segctor_clean(sci))
2033 goto out;
2034
2035 do {
2036 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2037
2038 err = nilfs_segctor_begin_construction(sci, nilfs);
2039 if (unlikely(err))
2040 goto out;
2041
2042 /* Update time stamp */
2043 sci->sc_seg_ctime = ktime_get_real_seconds();
2044
2045 err = nilfs_segctor_collect(sci, nilfs, mode);
2046 if (unlikely(err))
2047 goto failed;
2048
2049 /* Avoid empty segment */
2050 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2051 nilfs_segbuf_empty(sci->sc_curseg)) {
2052 nilfs_segctor_abort_construction(sci, nilfs, 1);
2053 goto out;
2054 }
2055
2056 err = nilfs_segctor_assign(sci, mode);
2057 if (unlikely(err))
2058 goto failed;
2059
2060 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2061 nilfs_segctor_fill_in_file_bmap(sci);
2062
2063 if (mode == SC_LSEG_SR &&
2064 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2065 err = nilfs_segctor_fill_in_checkpoint(sci);
2066 if (unlikely(err))
2067 goto failed_to_write;
2068
2069 nilfs_segctor_fill_in_super_root(sci, nilfs);
2070 }
2071 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2072
2073 /* Write partial segments */
2074 nilfs_segctor_prepare_write(sci);
2075
2076 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2077 nilfs->ns_crc_seed);
2078
2079 err = nilfs_segctor_write(sci, nilfs);
2080 if (unlikely(err))
2081 goto failed_to_write;
2082
2083 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2084 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2085 /*
2086 * At this point, we avoid double buffering
2087 * for blocksize < pagesize because page dirty
2088 * flag is turned off during write and dirty
2089 * buffers are not properly collected for
2090 * pages crossing over segments.
2091 */
2092 err = nilfs_segctor_wait(sci);
2093 if (err)
2094 goto failed_to_write;
2095 }
2096 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2097
2098 out:
2099 nilfs_segctor_drop_written_files(sci, nilfs);
2100 return err;
2101
2102 failed_to_write:
2103 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2104 nilfs_redirty_inodes(&sci->sc_dirty_files);
2105
2106 failed:
2107 if (nilfs_doing_gc())
2108 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2109 nilfs_segctor_abort_construction(sci, nilfs, err);
2110 goto out;
2111}
2112
2113/**
2114 * nilfs_segctor_start_timer - set timer of background write
2115 * @sci: nilfs_sc_info
2116 *
2117 * If the timer has already been set, it ignores the new request.
2118 * This function MUST be called within a section locking the segment
2119 * semaphore.
2120 */
2121static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2122{
2123 spin_lock(&sci->sc_state_lock);
2124 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2125 sci->sc_timer.expires = jiffies + sci->sc_interval;
2126 add_timer(&sci->sc_timer);
2127 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2128 }
2129 spin_unlock(&sci->sc_state_lock);
2130}
2131
2132static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2133{
2134 spin_lock(&sci->sc_state_lock);
2135 if (!(sci->sc_flush_request & BIT(bn))) {
2136 unsigned long prev_req = sci->sc_flush_request;
2137
2138 sci->sc_flush_request |= BIT(bn);
2139 if (!prev_req)
2140 wake_up(&sci->sc_wait_daemon);
2141 }
2142 spin_unlock(&sci->sc_state_lock);
2143}
2144
2145/**
2146 * nilfs_flush_segment - trigger a segment construction for resource control
2147 * @sb: super block
2148 * @ino: inode number of the file to be flushed out.
2149 */
2150void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2151{
2152 struct the_nilfs *nilfs = sb->s_fs_info;
2153 struct nilfs_sc_info *sci = nilfs->ns_writer;
2154
2155 if (!sci || nilfs_doing_construction())
2156 return;
2157 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2158 /* assign bit 0 to data files */
2159}
2160
2161struct nilfs_segctor_wait_request {
2162 wait_queue_entry_t wq;
2163 __u32 seq;
2164 int err;
2165 atomic_t done;
2166};
2167
2168static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2169{
2170 struct nilfs_segctor_wait_request wait_req;
2171 int err = 0;
2172
2173 spin_lock(&sci->sc_state_lock);
2174 init_wait(&wait_req.wq);
2175 wait_req.err = 0;
2176 atomic_set(&wait_req.done, 0);
2177 wait_req.seq = ++sci->sc_seq_request;
2178 spin_unlock(&sci->sc_state_lock);
2179
2180 init_waitqueue_entry(&wait_req.wq, current);
2181 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2182 set_current_state(TASK_INTERRUPTIBLE);
2183 wake_up(&sci->sc_wait_daemon);
2184
2185 for (;;) {
2186 if (atomic_read(&wait_req.done)) {
2187 err = wait_req.err;
2188 break;
2189 }
2190 if (!signal_pending(current)) {
2191 schedule();
2192 continue;
2193 }
2194 err = -ERESTARTSYS;
2195 break;
2196 }
2197 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2198 return err;
2199}
2200
2201static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2202{
2203 struct nilfs_segctor_wait_request *wrq, *n;
2204 unsigned long flags;
2205
2206 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2207 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
2208 if (!atomic_read(&wrq->done) &&
2209 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2210 wrq->err = err;
2211 atomic_set(&wrq->done, 1);
2212 }
2213 if (atomic_read(&wrq->done)) {
2214 wrq->wq.func(&wrq->wq,
2215 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2216 0, NULL);
2217 }
2218 }
2219 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2220}
2221
2222/**
2223 * nilfs_construct_segment - construct a logical segment
2224 * @sb: super block
2225 *
2226 * Return Value: On success, 0 is retured. On errors, one of the following
2227 * negative error code is returned.
2228 *
2229 * %-EROFS - Read only filesystem.
2230 *
2231 * %-EIO - I/O error
2232 *
2233 * %-ENOSPC - No space left on device (only in a panic state).
2234 *
2235 * %-ERESTARTSYS - Interrupted.
2236 *
2237 * %-ENOMEM - Insufficient memory available.
2238 */
2239int nilfs_construct_segment(struct super_block *sb)
2240{
2241 struct the_nilfs *nilfs = sb->s_fs_info;
2242 struct nilfs_sc_info *sci = nilfs->ns_writer;
2243 struct nilfs_transaction_info *ti;
2244 int err;
2245
2246 if (!sci)
2247 return -EROFS;
2248
2249 /* A call inside transactions causes a deadlock. */
2250 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2251
2252 err = nilfs_segctor_sync(sci);
2253 return err;
2254}
2255
2256/**
2257 * nilfs_construct_dsync_segment - construct a data-only logical segment
2258 * @sb: super block
2259 * @inode: inode whose data blocks should be written out
2260 * @start: start byte offset
2261 * @end: end byte offset (inclusive)
2262 *
2263 * Return Value: On success, 0 is retured. On errors, one of the following
2264 * negative error code is returned.
2265 *
2266 * %-EROFS - Read only filesystem.
2267 *
2268 * %-EIO - I/O error
2269 *
2270 * %-ENOSPC - No space left on device (only in a panic state).
2271 *
2272 * %-ERESTARTSYS - Interrupted.
2273 *
2274 * %-ENOMEM - Insufficient memory available.
2275 */
2276int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2277 loff_t start, loff_t end)
2278{
2279 struct the_nilfs *nilfs = sb->s_fs_info;
2280 struct nilfs_sc_info *sci = nilfs->ns_writer;
2281 struct nilfs_inode_info *ii;
2282 struct nilfs_transaction_info ti;
2283 int err = 0;
2284
2285 if (!sci)
2286 return -EROFS;
2287
2288 nilfs_transaction_lock(sb, &ti, 0);
2289
2290 ii = NILFS_I(inode);
2291 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2292 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2293 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2294 nilfs_discontinued(nilfs)) {
2295 nilfs_transaction_unlock(sb);
2296 err = nilfs_segctor_sync(sci);
2297 return err;
2298 }
2299
2300 spin_lock(&nilfs->ns_inode_lock);
2301 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2302 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2303 spin_unlock(&nilfs->ns_inode_lock);
2304 nilfs_transaction_unlock(sb);
2305 return 0;
2306 }
2307 spin_unlock(&nilfs->ns_inode_lock);
2308 sci->sc_dsync_inode = ii;
2309 sci->sc_dsync_start = start;
2310 sci->sc_dsync_end = end;
2311
2312 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2313 if (!err)
2314 nilfs->ns_flushed_device = 0;
2315
2316 nilfs_transaction_unlock(sb);
2317 return err;
2318}
2319
2320#define FLUSH_FILE_BIT (0x1) /* data file only */
2321#define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2322
2323/**
2324 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2325 * @sci: segment constructor object
2326 */
2327static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2328{
2329 spin_lock(&sci->sc_state_lock);
2330 sci->sc_seq_accepted = sci->sc_seq_request;
2331 spin_unlock(&sci->sc_state_lock);
2332 del_timer_sync(&sci->sc_timer);
2333}
2334
2335/**
2336 * nilfs_segctor_notify - notify the result of request to caller threads
2337 * @sci: segment constructor object
2338 * @mode: mode of log forming
2339 * @err: error code to be notified
2340 */
2341static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2342{
2343 /* Clear requests (even when the construction failed) */
2344 spin_lock(&sci->sc_state_lock);
2345
2346 if (mode == SC_LSEG_SR) {
2347 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2348 sci->sc_seq_done = sci->sc_seq_accepted;
2349 nilfs_segctor_wakeup(sci, err);
2350 sci->sc_flush_request = 0;
2351 } else {
2352 if (mode == SC_FLUSH_FILE)
2353 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2354 else if (mode == SC_FLUSH_DAT)
2355 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2356
2357 /* re-enable timer if checkpoint creation was not done */
2358 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2359 time_before(jiffies, sci->sc_timer.expires))
2360 add_timer(&sci->sc_timer);
2361 }
2362 spin_unlock(&sci->sc_state_lock);
2363}
2364
2365/**
2366 * nilfs_segctor_construct - form logs and write them to disk
2367 * @sci: segment constructor object
2368 * @mode: mode of log forming
2369 */
2370static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2371{
2372 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2373 struct nilfs_super_block **sbp;
2374 int err = 0;
2375
2376 nilfs_segctor_accept(sci);
2377
2378 if (nilfs_discontinued(nilfs))
2379 mode = SC_LSEG_SR;
2380 if (!nilfs_segctor_confirm(sci))
2381 err = nilfs_segctor_do_construct(sci, mode);
2382
2383 if (likely(!err)) {
2384 if (mode != SC_FLUSH_DAT)
2385 atomic_set(&nilfs->ns_ndirtyblks, 0);
2386 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2387 nilfs_discontinued(nilfs)) {
2388 down_write(&nilfs->ns_sem);
2389 err = -EIO;
2390 sbp = nilfs_prepare_super(sci->sc_super,
2391 nilfs_sb_will_flip(nilfs));
2392 if (likely(sbp)) {
2393 nilfs_set_log_cursor(sbp[0], nilfs);
2394 err = nilfs_commit_super(sci->sc_super,
2395 NILFS_SB_COMMIT);
2396 }
2397 up_write(&nilfs->ns_sem);
2398 }
2399 }
2400
2401 nilfs_segctor_notify(sci, mode, err);
2402 return err;
2403}
2404
2405static void nilfs_construction_timeout(struct timer_list *t)
2406{
2407 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2408
2409 wake_up_process(sci->sc_timer_task);
2410}
2411
2412static void
2413nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2414{
2415 struct nilfs_inode_info *ii, *n;
2416
2417 list_for_each_entry_safe(ii, n, head, i_dirty) {
2418 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2419 continue;
2420 list_del_init(&ii->i_dirty);
2421 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2422 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2423 iput(&ii->vfs_inode);
2424 }
2425}
2426
2427int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2428 void **kbufs)
2429{
2430 struct the_nilfs *nilfs = sb->s_fs_info;
2431 struct nilfs_sc_info *sci = nilfs->ns_writer;
2432 struct nilfs_transaction_info ti;
2433 int err;
2434
2435 if (unlikely(!sci))
2436 return -EROFS;
2437
2438 nilfs_transaction_lock(sb, &ti, 1);
2439
2440 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2441 if (unlikely(err))
2442 goto out_unlock;
2443
2444 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2445 if (unlikely(err)) {
2446 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2447 goto out_unlock;
2448 }
2449
2450 sci->sc_freesegs = kbufs[4];
2451 sci->sc_nfreesegs = argv[4].v_nmembs;
2452 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2453
2454 for (;;) {
2455 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2456 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2457
2458 if (likely(!err))
2459 break;
2460
2461 nilfs_msg(sb, KERN_WARNING, "error %d cleaning segments", err);
2462 set_current_state(TASK_INTERRUPTIBLE);
2463 schedule_timeout(sci->sc_interval);
2464 }
2465 if (nilfs_test_opt(nilfs, DISCARD)) {
2466 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2467 sci->sc_nfreesegs);
2468 if (ret) {
2469 nilfs_msg(sb, KERN_WARNING,
2470 "error %d on discard request, turning discards off for the device",
2471 ret);
2472 nilfs_clear_opt(nilfs, DISCARD);
2473 }
2474 }
2475
2476 out_unlock:
2477 sci->sc_freesegs = NULL;
2478 sci->sc_nfreesegs = 0;
2479 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2480 nilfs_transaction_unlock(sb);
2481 return err;
2482}
2483
2484static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2485{
2486 struct nilfs_transaction_info ti;
2487
2488 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2489 nilfs_segctor_construct(sci, mode);
2490
2491 /*
2492 * Unclosed segment should be retried. We do this using sc_timer.
2493 * Timeout of sc_timer will invoke complete construction which leads
2494 * to close the current logical segment.
2495 */
2496 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2497 nilfs_segctor_start_timer(sci);
2498
2499 nilfs_transaction_unlock(sci->sc_super);
2500}
2501
2502static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2503{
2504 int mode = 0;
2505
2506 spin_lock(&sci->sc_state_lock);
2507 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2508 SC_FLUSH_DAT : SC_FLUSH_FILE;
2509 spin_unlock(&sci->sc_state_lock);
2510
2511 if (mode) {
2512 nilfs_segctor_do_construct(sci, mode);
2513
2514 spin_lock(&sci->sc_state_lock);
2515 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2516 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2517 spin_unlock(&sci->sc_state_lock);
2518 }
2519 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2520}
2521
2522static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2523{
2524 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2525 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2526 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2527 return SC_FLUSH_FILE;
2528 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2529 return SC_FLUSH_DAT;
2530 }
2531 return SC_LSEG_SR;
2532}
2533
2534/**
2535 * nilfs_segctor_thread - main loop of the segment constructor thread.
2536 * @arg: pointer to a struct nilfs_sc_info.
2537 *
2538 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2539 * to execute segment constructions.
2540 */
2541static int nilfs_segctor_thread(void *arg)
2542{
2543 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2544 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2545 int timeout = 0;
2546
2547 sci->sc_timer_task = current;
2548
2549 /* start sync. */
2550 sci->sc_task = current;
2551 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2552 nilfs_msg(sci->sc_super, KERN_INFO,
2553 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
2554 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2555
2556 spin_lock(&sci->sc_state_lock);
2557 loop:
2558 for (;;) {
2559 int mode;
2560
2561 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2562 goto end_thread;
2563
2564 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2565 mode = SC_LSEG_SR;
2566 else if (sci->sc_flush_request)
2567 mode = nilfs_segctor_flush_mode(sci);
2568 else
2569 break;
2570
2571 spin_unlock(&sci->sc_state_lock);
2572 nilfs_segctor_thread_construct(sci, mode);
2573 spin_lock(&sci->sc_state_lock);
2574 timeout = 0;
2575 }
2576
2577
2578 if (freezing(current)) {
2579 spin_unlock(&sci->sc_state_lock);
2580 try_to_freeze();
2581 spin_lock(&sci->sc_state_lock);
2582 } else {
2583 DEFINE_WAIT(wait);
2584 int should_sleep = 1;
2585
2586 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2587 TASK_INTERRUPTIBLE);
2588
2589 if (sci->sc_seq_request != sci->sc_seq_done)
2590 should_sleep = 0;
2591 else if (sci->sc_flush_request)
2592 should_sleep = 0;
2593 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2594 should_sleep = time_before(jiffies,
2595 sci->sc_timer.expires);
2596
2597 if (should_sleep) {
2598 spin_unlock(&sci->sc_state_lock);
2599 schedule();
2600 spin_lock(&sci->sc_state_lock);
2601 }
2602 finish_wait(&sci->sc_wait_daemon, &wait);
2603 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2604 time_after_eq(jiffies, sci->sc_timer.expires));
2605
2606 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2607 set_nilfs_discontinued(nilfs);
2608 }
2609 goto loop;
2610
2611 end_thread:
2612 spin_unlock(&sci->sc_state_lock);
2613
2614 /* end sync. */
2615 sci->sc_task = NULL;
2616 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2617 return 0;
2618}
2619
2620static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2621{
2622 struct task_struct *t;
2623
2624 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2625 if (IS_ERR(t)) {
2626 int err = PTR_ERR(t);
2627
2628 nilfs_msg(sci->sc_super, KERN_ERR,
2629 "error %d creating segctord thread", err);
2630 return err;
2631 }
2632 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2633 return 0;
2634}
2635
2636static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2637 __acquires(&sci->sc_state_lock)
2638 __releases(&sci->sc_state_lock)
2639{
2640 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2641
2642 while (sci->sc_task) {
2643 wake_up(&sci->sc_wait_daemon);
2644 spin_unlock(&sci->sc_state_lock);
2645 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2646 spin_lock(&sci->sc_state_lock);
2647 }
2648}
2649
2650/*
2651 * Setup & clean-up functions
2652 */
2653static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2654 struct nilfs_root *root)
2655{
2656 struct the_nilfs *nilfs = sb->s_fs_info;
2657 struct nilfs_sc_info *sci;
2658
2659 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2660 if (!sci)
2661 return NULL;
2662
2663 sci->sc_super = sb;
2664
2665 nilfs_get_root(root);
2666 sci->sc_root = root;
2667
2668 init_waitqueue_head(&sci->sc_wait_request);
2669 init_waitqueue_head(&sci->sc_wait_daemon);
2670 init_waitqueue_head(&sci->sc_wait_task);
2671 spin_lock_init(&sci->sc_state_lock);
2672 INIT_LIST_HEAD(&sci->sc_dirty_files);
2673 INIT_LIST_HEAD(&sci->sc_segbufs);
2674 INIT_LIST_HEAD(&sci->sc_write_logs);
2675 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2676 INIT_LIST_HEAD(&sci->sc_iput_queue);
2677 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2678 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
2679
2680 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2681 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2682 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2683
2684 if (nilfs->ns_interval)
2685 sci->sc_interval = HZ * nilfs->ns_interval;
2686 if (nilfs->ns_watermark)
2687 sci->sc_watermark = nilfs->ns_watermark;
2688 return sci;
2689}
2690
2691static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2692{
2693 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2694
2695 /*
2696 * The segctord thread was stopped and its timer was removed.
2697 * But some tasks remain.
2698 */
2699 do {
2700 struct nilfs_transaction_info ti;
2701
2702 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2703 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2704 nilfs_transaction_unlock(sci->sc_super);
2705
2706 flush_work(&sci->sc_iput_work);
2707
2708 } while (ret && retrycount-- > 0);
2709}
2710
2711/**
2712 * nilfs_segctor_destroy - destroy the segment constructor.
2713 * @sci: nilfs_sc_info
2714 *
2715 * nilfs_segctor_destroy() kills the segctord thread and frees
2716 * the nilfs_sc_info struct.
2717 * Caller must hold the segment semaphore.
2718 */
2719static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2720{
2721 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2722 int flag;
2723
2724 up_write(&nilfs->ns_segctor_sem);
2725
2726 spin_lock(&sci->sc_state_lock);
2727 nilfs_segctor_kill_thread(sci);
2728 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2729 || sci->sc_seq_request != sci->sc_seq_done);
2730 spin_unlock(&sci->sc_state_lock);
2731
2732 if (flush_work(&sci->sc_iput_work))
2733 flag = true;
2734
2735 if (flag || !nilfs_segctor_confirm(sci))
2736 nilfs_segctor_write_out(sci);
2737
2738 if (!list_empty(&sci->sc_dirty_files)) {
2739 nilfs_msg(sci->sc_super, KERN_WARNING,
2740 "disposed unprocessed dirty file(s) when stopping log writer");
2741 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2742 }
2743
2744 if (!list_empty(&sci->sc_iput_queue)) {
2745 nilfs_msg(sci->sc_super, KERN_WARNING,
2746 "disposed unprocessed inode(s) in iput queue when stopping log writer");
2747 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2748 }
2749
2750 WARN_ON(!list_empty(&sci->sc_segbufs));
2751 WARN_ON(!list_empty(&sci->sc_write_logs));
2752
2753 nilfs_put_root(sci->sc_root);
2754
2755 down_write(&nilfs->ns_segctor_sem);
2756
2757 del_timer_sync(&sci->sc_timer);
2758 kfree(sci);
2759}
2760
2761/**
2762 * nilfs_attach_log_writer - attach log writer
2763 * @sb: super block instance
2764 * @root: root object of the current filesystem tree
2765 *
2766 * This allocates a log writer object, initializes it, and starts the
2767 * log writer.
2768 *
2769 * Return Value: On success, 0 is returned. On error, one of the following
2770 * negative error code is returned.
2771 *
2772 * %-ENOMEM - Insufficient memory available.
2773 */
2774int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2775{
2776 struct the_nilfs *nilfs = sb->s_fs_info;
2777 int err;
2778
2779 if (nilfs->ns_writer) {
2780 /*
2781 * This happens if the filesystem was remounted
2782 * read/write after nilfs_error degenerated it into a
2783 * read-only mount.
2784 */
2785 nilfs_detach_log_writer(sb);
2786 }
2787
2788 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2789 if (!nilfs->ns_writer)
2790 return -ENOMEM;
2791
2792 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2793 if (err) {
2794 kfree(nilfs->ns_writer);
2795 nilfs->ns_writer = NULL;
2796 }
2797 return err;
2798}
2799
2800/**
2801 * nilfs_detach_log_writer - destroy log writer
2802 * @sb: super block instance
2803 *
2804 * This kills log writer daemon, frees the log writer object, and
2805 * destroys list of dirty files.
2806 */
2807void nilfs_detach_log_writer(struct super_block *sb)
2808{
2809 struct the_nilfs *nilfs = sb->s_fs_info;
2810 LIST_HEAD(garbage_list);
2811
2812 down_write(&nilfs->ns_segctor_sem);
2813 if (nilfs->ns_writer) {
2814 nilfs_segctor_destroy(nilfs->ns_writer);
2815 nilfs->ns_writer = NULL;
2816 }
2817
2818 /* Force to free the list of dirty files */
2819 spin_lock(&nilfs->ns_inode_lock);
2820 if (!list_empty(&nilfs->ns_dirty_files)) {
2821 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2822 nilfs_msg(sb, KERN_WARNING,
2823 "disposed unprocessed dirty file(s) when detaching log writer");
2824 }
2825 spin_unlock(&nilfs->ns_inode_lock);
2826 up_write(&nilfs->ns_segctor_sem);
2827
2828 nilfs_dispose_list(nilfs, &garbage_list, 1);
2829}
1/*
2 * segment.c - NILFS segment constructor.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
21 *
22 */
23
24#include <linux/pagemap.h>
25#include <linux/buffer_head.h>
26#include <linux/writeback.h>
27#include <linux/bio.h>
28#include <linux/completion.h>
29#include <linux/blkdev.h>
30#include <linux/backing-dev.h>
31#include <linux/freezer.h>
32#include <linux/kthread.h>
33#include <linux/crc32.h>
34#include <linux/pagevec.h>
35#include <linux/slab.h>
36#include "nilfs.h"
37#include "btnode.h"
38#include "page.h"
39#include "segment.h"
40#include "sufile.h"
41#include "cpfile.h"
42#include "ifile.h"
43#include "segbuf.h"
44
45
46/*
47 * Segment constructor
48 */
49#define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
50
51#define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments
52 appended in collection retry loop */
53
54/* Construction mode */
55enum {
56 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
57 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make
58 a logical segment without a super root */
59 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without
60 creating a checkpoint */
61 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without
62 a checkpoint */
63};
64
65/* Stage numbers of dirty block collection */
66enum {
67 NILFS_ST_INIT = 0,
68 NILFS_ST_GC, /* Collecting dirty blocks for GC */
69 NILFS_ST_FILE,
70 NILFS_ST_IFILE,
71 NILFS_ST_CPFILE,
72 NILFS_ST_SUFILE,
73 NILFS_ST_DAT,
74 NILFS_ST_SR, /* Super root */
75 NILFS_ST_DSYNC, /* Data sync blocks */
76 NILFS_ST_DONE,
77};
78
79/* State flags of collection */
80#define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
81#define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
82#define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
83#define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
84
85/* Operations depending on the construction mode and file type */
86struct nilfs_sc_operations {
87 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
88 struct inode *);
89 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
90 struct inode *);
91 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
92 struct inode *);
93 void (*write_data_binfo)(struct nilfs_sc_info *,
94 struct nilfs_segsum_pointer *,
95 union nilfs_binfo *);
96 void (*write_node_binfo)(struct nilfs_sc_info *,
97 struct nilfs_segsum_pointer *,
98 union nilfs_binfo *);
99};
100
101/*
102 * Other definitions
103 */
104static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
105static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
106static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
107static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
108
109#define nilfs_cnt32_gt(a, b) \
110 (typecheck(__u32, a) && typecheck(__u32, b) && \
111 ((__s32)(b) - (__s32)(a) < 0))
112#define nilfs_cnt32_ge(a, b) \
113 (typecheck(__u32, a) && typecheck(__u32, b) && \
114 ((__s32)(a) - (__s32)(b) >= 0))
115#define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
116#define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
117
118static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
119{
120 struct nilfs_transaction_info *cur_ti = current->journal_info;
121 void *save = NULL;
122
123 if (cur_ti) {
124 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
125 return ++cur_ti->ti_count;
126 else {
127 /*
128 * If journal_info field is occupied by other FS,
129 * it is saved and will be restored on
130 * nilfs_transaction_commit().
131 */
132 printk(KERN_WARNING
133 "NILFS warning: journal info from a different "
134 "FS\n");
135 save = current->journal_info;
136 }
137 }
138 if (!ti) {
139 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
140 if (!ti)
141 return -ENOMEM;
142 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
143 } else {
144 ti->ti_flags = 0;
145 }
146 ti->ti_count = 0;
147 ti->ti_save = save;
148 ti->ti_magic = NILFS_TI_MAGIC;
149 current->journal_info = ti;
150 return 0;
151}
152
153/**
154 * nilfs_transaction_begin - start indivisible file operations.
155 * @sb: super block
156 * @ti: nilfs_transaction_info
157 * @vacancy_check: flags for vacancy rate checks
158 *
159 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
160 * the segment semaphore, to make a segment construction and write tasks
161 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
162 * The region enclosed by these two functions can be nested. To avoid a
163 * deadlock, the semaphore is only acquired or released in the outermost call.
164 *
165 * This function allocates a nilfs_transaction_info struct to keep context
166 * information on it. It is initialized and hooked onto the current task in
167 * the outermost call. If a pre-allocated struct is given to @ti, it is used
168 * instead; otherwise a new struct is assigned from a slab.
169 *
170 * When @vacancy_check flag is set, this function will check the amount of
171 * free space, and will wait for the GC to reclaim disk space if low capacity.
172 *
173 * Return Value: On success, 0 is returned. On error, one of the following
174 * negative error code is returned.
175 *
176 * %-ENOMEM - Insufficient memory available.
177 *
178 * %-ENOSPC - No space left on device
179 */
180int nilfs_transaction_begin(struct super_block *sb,
181 struct nilfs_transaction_info *ti,
182 int vacancy_check)
183{
184 struct the_nilfs *nilfs;
185 int ret = nilfs_prepare_segment_lock(ti);
186
187 if (unlikely(ret < 0))
188 return ret;
189 if (ret > 0)
190 return 0;
191
192 sb_start_intwrite(sb);
193
194 nilfs = sb->s_fs_info;
195 down_read(&nilfs->ns_segctor_sem);
196 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
197 up_read(&nilfs->ns_segctor_sem);
198 ret = -ENOSPC;
199 goto failed;
200 }
201 return 0;
202
203 failed:
204 ti = current->journal_info;
205 current->journal_info = ti->ti_save;
206 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
207 kmem_cache_free(nilfs_transaction_cachep, ti);
208 sb_end_intwrite(sb);
209 return ret;
210}
211
212/**
213 * nilfs_transaction_commit - commit indivisible file operations.
214 * @sb: super block
215 *
216 * nilfs_transaction_commit() releases the read semaphore which is
217 * acquired by nilfs_transaction_begin(). This is only performed
218 * in outermost call of this function. If a commit flag is set,
219 * nilfs_transaction_commit() sets a timer to start the segment
220 * constructor. If a sync flag is set, it starts construction
221 * directly.
222 */
223int nilfs_transaction_commit(struct super_block *sb)
224{
225 struct nilfs_transaction_info *ti = current->journal_info;
226 struct the_nilfs *nilfs = sb->s_fs_info;
227 int err = 0;
228
229 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
230 ti->ti_flags |= NILFS_TI_COMMIT;
231 if (ti->ti_count > 0) {
232 ti->ti_count--;
233 return 0;
234 }
235 if (nilfs->ns_writer) {
236 struct nilfs_sc_info *sci = nilfs->ns_writer;
237
238 if (ti->ti_flags & NILFS_TI_COMMIT)
239 nilfs_segctor_start_timer(sci);
240 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
241 nilfs_segctor_do_flush(sci, 0);
242 }
243 up_read(&nilfs->ns_segctor_sem);
244 current->journal_info = ti->ti_save;
245
246 if (ti->ti_flags & NILFS_TI_SYNC)
247 err = nilfs_construct_segment(sb);
248 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
249 kmem_cache_free(nilfs_transaction_cachep, ti);
250 sb_end_intwrite(sb);
251 return err;
252}
253
254void nilfs_transaction_abort(struct super_block *sb)
255{
256 struct nilfs_transaction_info *ti = current->journal_info;
257 struct the_nilfs *nilfs = sb->s_fs_info;
258
259 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
260 if (ti->ti_count > 0) {
261 ti->ti_count--;
262 return;
263 }
264 up_read(&nilfs->ns_segctor_sem);
265
266 current->journal_info = ti->ti_save;
267 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
268 kmem_cache_free(nilfs_transaction_cachep, ti);
269 sb_end_intwrite(sb);
270}
271
272void nilfs_relax_pressure_in_lock(struct super_block *sb)
273{
274 struct the_nilfs *nilfs = sb->s_fs_info;
275 struct nilfs_sc_info *sci = nilfs->ns_writer;
276
277 if (!sci || !sci->sc_flush_request)
278 return;
279
280 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
281 up_read(&nilfs->ns_segctor_sem);
282
283 down_write(&nilfs->ns_segctor_sem);
284 if (sci->sc_flush_request &&
285 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
286 struct nilfs_transaction_info *ti = current->journal_info;
287
288 ti->ti_flags |= NILFS_TI_WRITER;
289 nilfs_segctor_do_immediate_flush(sci);
290 ti->ti_flags &= ~NILFS_TI_WRITER;
291 }
292 downgrade_write(&nilfs->ns_segctor_sem);
293}
294
295static void nilfs_transaction_lock(struct super_block *sb,
296 struct nilfs_transaction_info *ti,
297 int gcflag)
298{
299 struct nilfs_transaction_info *cur_ti = current->journal_info;
300 struct the_nilfs *nilfs = sb->s_fs_info;
301 struct nilfs_sc_info *sci = nilfs->ns_writer;
302
303 WARN_ON(cur_ti);
304 ti->ti_flags = NILFS_TI_WRITER;
305 ti->ti_count = 0;
306 ti->ti_save = cur_ti;
307 ti->ti_magic = NILFS_TI_MAGIC;
308 INIT_LIST_HEAD(&ti->ti_garbage);
309 current->journal_info = ti;
310
311 for (;;) {
312 down_write(&nilfs->ns_segctor_sem);
313 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
314 break;
315
316 nilfs_segctor_do_immediate_flush(sci);
317
318 up_write(&nilfs->ns_segctor_sem);
319 yield();
320 }
321 if (gcflag)
322 ti->ti_flags |= NILFS_TI_GC;
323}
324
325static void nilfs_transaction_unlock(struct super_block *sb)
326{
327 struct nilfs_transaction_info *ti = current->journal_info;
328 struct the_nilfs *nilfs = sb->s_fs_info;
329
330 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
331 BUG_ON(ti->ti_count > 0);
332
333 up_write(&nilfs->ns_segctor_sem);
334 current->journal_info = ti->ti_save;
335 if (!list_empty(&ti->ti_garbage))
336 nilfs_dispose_list(nilfs, &ti->ti_garbage, 0);
337}
338
339static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
340 struct nilfs_segsum_pointer *ssp,
341 unsigned bytes)
342{
343 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
344 unsigned blocksize = sci->sc_super->s_blocksize;
345 void *p;
346
347 if (unlikely(ssp->offset + bytes > blocksize)) {
348 ssp->offset = 0;
349 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
350 &segbuf->sb_segsum_buffers));
351 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
352 }
353 p = ssp->bh->b_data + ssp->offset;
354 ssp->offset += bytes;
355 return p;
356}
357
358/**
359 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
360 * @sci: nilfs_sc_info
361 */
362static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
363{
364 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
365 struct buffer_head *sumbh;
366 unsigned sumbytes;
367 unsigned flags = 0;
368 int err;
369
370 if (nilfs_doing_gc())
371 flags = NILFS_SS_GC;
372 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
373 if (unlikely(err))
374 return err;
375
376 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
377 sumbytes = segbuf->sb_sum.sumbytes;
378 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
379 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
380 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
381 return 0;
382}
383
384static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
385{
386 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
387 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
388 return -E2BIG; /* The current segment is filled up
389 (internal code) */
390 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
391 return nilfs_segctor_reset_segment_buffer(sci);
392}
393
394static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
395{
396 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
397 int err;
398
399 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
400 err = nilfs_segctor_feed_segment(sci);
401 if (err)
402 return err;
403 segbuf = sci->sc_curseg;
404 }
405 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
406 if (likely(!err))
407 segbuf->sb_sum.flags |= NILFS_SS_SR;
408 return err;
409}
410
411/*
412 * Functions for making segment summary and payloads
413 */
414static int nilfs_segctor_segsum_block_required(
415 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
416 unsigned binfo_size)
417{
418 unsigned blocksize = sci->sc_super->s_blocksize;
419 /* Size of finfo and binfo is enough small against blocksize */
420
421 return ssp->offset + binfo_size +
422 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
423 blocksize;
424}
425
426static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
427 struct inode *inode)
428{
429 sci->sc_curseg->sb_sum.nfinfo++;
430 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
431 nilfs_segctor_map_segsum_entry(
432 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
433
434 if (NILFS_I(inode)->i_root &&
435 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
436 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
437 /* skip finfo */
438}
439
440static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
441 struct inode *inode)
442{
443 struct nilfs_finfo *finfo;
444 struct nilfs_inode_info *ii;
445 struct nilfs_segment_buffer *segbuf;
446 __u64 cno;
447
448 if (sci->sc_blk_cnt == 0)
449 return;
450
451 ii = NILFS_I(inode);
452
453 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
454 cno = ii->i_cno;
455 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
456 cno = 0;
457 else
458 cno = sci->sc_cno;
459
460 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
461 sizeof(*finfo));
462 finfo->fi_ino = cpu_to_le64(inode->i_ino);
463 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
464 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
465 finfo->fi_cno = cpu_to_le64(cno);
466
467 segbuf = sci->sc_curseg;
468 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
469 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
470 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
471 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
472}
473
474static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
475 struct buffer_head *bh,
476 struct inode *inode,
477 unsigned binfo_size)
478{
479 struct nilfs_segment_buffer *segbuf;
480 int required, err = 0;
481
482 retry:
483 segbuf = sci->sc_curseg;
484 required = nilfs_segctor_segsum_block_required(
485 sci, &sci->sc_binfo_ptr, binfo_size);
486 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
487 nilfs_segctor_end_finfo(sci, inode);
488 err = nilfs_segctor_feed_segment(sci);
489 if (err)
490 return err;
491 goto retry;
492 }
493 if (unlikely(required)) {
494 err = nilfs_segbuf_extend_segsum(segbuf);
495 if (unlikely(err))
496 goto failed;
497 }
498 if (sci->sc_blk_cnt == 0)
499 nilfs_segctor_begin_finfo(sci, inode);
500
501 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
502 /* Substitution to vblocknr is delayed until update_blocknr() */
503 nilfs_segbuf_add_file_buffer(segbuf, bh);
504 sci->sc_blk_cnt++;
505 failed:
506 return err;
507}
508
509/*
510 * Callback functions that enumerate, mark, and collect dirty blocks
511 */
512static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
513 struct buffer_head *bh, struct inode *inode)
514{
515 int err;
516
517 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
518 if (err < 0)
519 return err;
520
521 err = nilfs_segctor_add_file_block(sci, bh, inode,
522 sizeof(struct nilfs_binfo_v));
523 if (!err)
524 sci->sc_datablk_cnt++;
525 return err;
526}
527
528static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
529 struct buffer_head *bh,
530 struct inode *inode)
531{
532 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
533}
534
535static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
536 struct buffer_head *bh,
537 struct inode *inode)
538{
539 WARN_ON(!buffer_dirty(bh));
540 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
541}
542
543static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
544 struct nilfs_segsum_pointer *ssp,
545 union nilfs_binfo *binfo)
546{
547 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
548 sci, ssp, sizeof(*binfo_v));
549 *binfo_v = binfo->bi_v;
550}
551
552static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
553 struct nilfs_segsum_pointer *ssp,
554 union nilfs_binfo *binfo)
555{
556 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
557 sci, ssp, sizeof(*vblocknr));
558 *vblocknr = binfo->bi_v.bi_vblocknr;
559}
560
561static struct nilfs_sc_operations nilfs_sc_file_ops = {
562 .collect_data = nilfs_collect_file_data,
563 .collect_node = nilfs_collect_file_node,
564 .collect_bmap = nilfs_collect_file_bmap,
565 .write_data_binfo = nilfs_write_file_data_binfo,
566 .write_node_binfo = nilfs_write_file_node_binfo,
567};
568
569static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
570 struct buffer_head *bh, struct inode *inode)
571{
572 int err;
573
574 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
575 if (err < 0)
576 return err;
577
578 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
579 if (!err)
580 sci->sc_datablk_cnt++;
581 return err;
582}
583
584static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
585 struct buffer_head *bh, struct inode *inode)
586{
587 WARN_ON(!buffer_dirty(bh));
588 return nilfs_segctor_add_file_block(sci, bh, inode,
589 sizeof(struct nilfs_binfo_dat));
590}
591
592static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
593 struct nilfs_segsum_pointer *ssp,
594 union nilfs_binfo *binfo)
595{
596 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
597 sizeof(*blkoff));
598 *blkoff = binfo->bi_dat.bi_blkoff;
599}
600
601static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
602 struct nilfs_segsum_pointer *ssp,
603 union nilfs_binfo *binfo)
604{
605 struct nilfs_binfo_dat *binfo_dat =
606 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
607 *binfo_dat = binfo->bi_dat;
608}
609
610static struct nilfs_sc_operations nilfs_sc_dat_ops = {
611 .collect_data = nilfs_collect_dat_data,
612 .collect_node = nilfs_collect_file_node,
613 .collect_bmap = nilfs_collect_dat_bmap,
614 .write_data_binfo = nilfs_write_dat_data_binfo,
615 .write_node_binfo = nilfs_write_dat_node_binfo,
616};
617
618static struct nilfs_sc_operations nilfs_sc_dsync_ops = {
619 .collect_data = nilfs_collect_file_data,
620 .collect_node = NULL,
621 .collect_bmap = NULL,
622 .write_data_binfo = nilfs_write_file_data_binfo,
623 .write_node_binfo = NULL,
624};
625
626static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
627 struct list_head *listp,
628 size_t nlimit,
629 loff_t start, loff_t end)
630{
631 struct address_space *mapping = inode->i_mapping;
632 struct pagevec pvec;
633 pgoff_t index = 0, last = ULONG_MAX;
634 size_t ndirties = 0;
635 int i;
636
637 if (unlikely(start != 0 || end != LLONG_MAX)) {
638 /*
639 * A valid range is given for sync-ing data pages. The
640 * range is rounded to per-page; extra dirty buffers
641 * may be included if blocksize < pagesize.
642 */
643 index = start >> PAGE_SHIFT;
644 last = end >> PAGE_SHIFT;
645 }
646 pagevec_init(&pvec, 0);
647 repeat:
648 if (unlikely(index > last) ||
649 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
650 min_t(pgoff_t, last - index,
651 PAGEVEC_SIZE - 1) + 1))
652 return ndirties;
653
654 for (i = 0; i < pagevec_count(&pvec); i++) {
655 struct buffer_head *bh, *head;
656 struct page *page = pvec.pages[i];
657
658 if (unlikely(page->index > last))
659 break;
660
661 lock_page(page);
662 if (!page_has_buffers(page))
663 create_empty_buffers(page, 1 << inode->i_blkbits, 0);
664 unlock_page(page);
665
666 bh = head = page_buffers(page);
667 do {
668 if (!buffer_dirty(bh) || buffer_async_write(bh))
669 continue;
670 get_bh(bh);
671 list_add_tail(&bh->b_assoc_buffers, listp);
672 ndirties++;
673 if (unlikely(ndirties >= nlimit)) {
674 pagevec_release(&pvec);
675 cond_resched();
676 return ndirties;
677 }
678 } while (bh = bh->b_this_page, bh != head);
679 }
680 pagevec_release(&pvec);
681 cond_resched();
682 goto repeat;
683}
684
685static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
686 struct list_head *listp)
687{
688 struct nilfs_inode_info *ii = NILFS_I(inode);
689 struct address_space *mapping = &ii->i_btnode_cache;
690 struct pagevec pvec;
691 struct buffer_head *bh, *head;
692 unsigned int i;
693 pgoff_t index = 0;
694
695 pagevec_init(&pvec, 0);
696
697 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
698 PAGEVEC_SIZE)) {
699 for (i = 0; i < pagevec_count(&pvec); i++) {
700 bh = head = page_buffers(pvec.pages[i]);
701 do {
702 if (buffer_dirty(bh) &&
703 !buffer_async_write(bh)) {
704 get_bh(bh);
705 list_add_tail(&bh->b_assoc_buffers,
706 listp);
707 }
708 bh = bh->b_this_page;
709 } while (bh != head);
710 }
711 pagevec_release(&pvec);
712 cond_resched();
713 }
714}
715
716static void nilfs_dispose_list(struct the_nilfs *nilfs,
717 struct list_head *head, int force)
718{
719 struct nilfs_inode_info *ii, *n;
720 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
721 unsigned nv = 0;
722
723 while (!list_empty(head)) {
724 spin_lock(&nilfs->ns_inode_lock);
725 list_for_each_entry_safe(ii, n, head, i_dirty) {
726 list_del_init(&ii->i_dirty);
727 if (force) {
728 if (unlikely(ii->i_bh)) {
729 brelse(ii->i_bh);
730 ii->i_bh = NULL;
731 }
732 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
733 set_bit(NILFS_I_QUEUED, &ii->i_state);
734 list_add_tail(&ii->i_dirty,
735 &nilfs->ns_dirty_files);
736 continue;
737 }
738 ivec[nv++] = ii;
739 if (nv == SC_N_INODEVEC)
740 break;
741 }
742 spin_unlock(&nilfs->ns_inode_lock);
743
744 for (pii = ivec; nv > 0; pii++, nv--)
745 iput(&(*pii)->vfs_inode);
746 }
747}
748
749static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
750 struct nilfs_root *root)
751{
752 int ret = 0;
753
754 if (nilfs_mdt_fetch_dirty(root->ifile))
755 ret++;
756 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
757 ret++;
758 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
759 ret++;
760 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
761 ret++;
762 return ret;
763}
764
765static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
766{
767 return list_empty(&sci->sc_dirty_files) &&
768 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
769 sci->sc_nfreesegs == 0 &&
770 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
771}
772
773static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
774{
775 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
776 int ret = 0;
777
778 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
779 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
780
781 spin_lock(&nilfs->ns_inode_lock);
782 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
783 ret++;
784
785 spin_unlock(&nilfs->ns_inode_lock);
786 return ret;
787}
788
789static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
790{
791 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
792
793 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
794 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
795 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
796 nilfs_mdt_clear_dirty(nilfs->ns_dat);
797}
798
799static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
800{
801 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
802 struct buffer_head *bh_cp;
803 struct nilfs_checkpoint *raw_cp;
804 int err;
805
806 /* XXX: this interface will be changed */
807 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
808 &raw_cp, &bh_cp);
809 if (likely(!err)) {
810 /* The following code is duplicated with cpfile. But, it is
811 needed to collect the checkpoint even if it was not newly
812 created */
813 mark_buffer_dirty(bh_cp);
814 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
815 nilfs_cpfile_put_checkpoint(
816 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
817 } else
818 WARN_ON(err == -EINVAL || err == -ENOENT);
819
820 return err;
821}
822
823static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
824{
825 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
826 struct buffer_head *bh_cp;
827 struct nilfs_checkpoint *raw_cp;
828 int err;
829
830 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
831 &raw_cp, &bh_cp);
832 if (unlikely(err)) {
833 WARN_ON(err == -EINVAL || err == -ENOENT);
834 goto failed_ibh;
835 }
836 raw_cp->cp_snapshot_list.ssl_next = 0;
837 raw_cp->cp_snapshot_list.ssl_prev = 0;
838 raw_cp->cp_inodes_count =
839 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
840 raw_cp->cp_blocks_count =
841 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
842 raw_cp->cp_nblk_inc =
843 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
844 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
845 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
846
847 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
848 nilfs_checkpoint_clear_minor(raw_cp);
849 else
850 nilfs_checkpoint_set_minor(raw_cp);
851
852 nilfs_write_inode_common(sci->sc_root->ifile,
853 &raw_cp->cp_ifile_inode, 1);
854 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
855 return 0;
856
857 failed_ibh:
858 return err;
859}
860
861static void nilfs_fill_in_file_bmap(struct inode *ifile,
862 struct nilfs_inode_info *ii)
863
864{
865 struct buffer_head *ibh;
866 struct nilfs_inode *raw_inode;
867
868 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
869 ibh = ii->i_bh;
870 BUG_ON(!ibh);
871 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
872 ibh);
873 nilfs_bmap_write(ii->i_bmap, raw_inode);
874 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
875 }
876}
877
878static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
879{
880 struct nilfs_inode_info *ii;
881
882 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
883 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
884 set_bit(NILFS_I_COLLECTED, &ii->i_state);
885 }
886}
887
888static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
889 struct the_nilfs *nilfs)
890{
891 struct buffer_head *bh_sr;
892 struct nilfs_super_root *raw_sr;
893 unsigned isz, srsz;
894
895 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
896 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
897 isz = nilfs->ns_inode_size;
898 srsz = NILFS_SR_BYTES(isz);
899
900 raw_sr->sr_bytes = cpu_to_le16(srsz);
901 raw_sr->sr_nongc_ctime
902 = cpu_to_le64(nilfs_doing_gc() ?
903 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
904 raw_sr->sr_flags = 0;
905
906 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
907 NILFS_SR_DAT_OFFSET(isz), 1);
908 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
909 NILFS_SR_CPFILE_OFFSET(isz), 1);
910 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
911 NILFS_SR_SUFILE_OFFSET(isz), 1);
912 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
913}
914
915static void nilfs_redirty_inodes(struct list_head *head)
916{
917 struct nilfs_inode_info *ii;
918
919 list_for_each_entry(ii, head, i_dirty) {
920 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
921 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
922 }
923}
924
925static void nilfs_drop_collected_inodes(struct list_head *head)
926{
927 struct nilfs_inode_info *ii;
928
929 list_for_each_entry(ii, head, i_dirty) {
930 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
931 continue;
932
933 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
934 set_bit(NILFS_I_UPDATED, &ii->i_state);
935 }
936}
937
938static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
939 struct inode *inode,
940 struct list_head *listp,
941 int (*collect)(struct nilfs_sc_info *,
942 struct buffer_head *,
943 struct inode *))
944{
945 struct buffer_head *bh, *n;
946 int err = 0;
947
948 if (collect) {
949 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
950 list_del_init(&bh->b_assoc_buffers);
951 err = collect(sci, bh, inode);
952 brelse(bh);
953 if (unlikely(err))
954 goto dispose_buffers;
955 }
956 return 0;
957 }
958
959 dispose_buffers:
960 while (!list_empty(listp)) {
961 bh = list_first_entry(listp, struct buffer_head,
962 b_assoc_buffers);
963 list_del_init(&bh->b_assoc_buffers);
964 brelse(bh);
965 }
966 return err;
967}
968
969static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
970{
971 /* Remaining number of blocks within segment buffer */
972 return sci->sc_segbuf_nblocks -
973 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
974}
975
976static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
977 struct inode *inode,
978 struct nilfs_sc_operations *sc_ops)
979{
980 LIST_HEAD(data_buffers);
981 LIST_HEAD(node_buffers);
982 int err;
983
984 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
985 size_t n, rest = nilfs_segctor_buffer_rest(sci);
986
987 n = nilfs_lookup_dirty_data_buffers(
988 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
989 if (n > rest) {
990 err = nilfs_segctor_apply_buffers(
991 sci, inode, &data_buffers,
992 sc_ops->collect_data);
993 BUG_ON(!err); /* always receive -E2BIG or true error */
994 goto break_or_fail;
995 }
996 }
997 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
998
999 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1000 err = nilfs_segctor_apply_buffers(
1001 sci, inode, &data_buffers, sc_ops->collect_data);
1002 if (unlikely(err)) {
1003 /* dispose node list */
1004 nilfs_segctor_apply_buffers(
1005 sci, inode, &node_buffers, NULL);
1006 goto break_or_fail;
1007 }
1008 sci->sc_stage.flags |= NILFS_CF_NODE;
1009 }
1010 /* Collect node */
1011 err = nilfs_segctor_apply_buffers(
1012 sci, inode, &node_buffers, sc_ops->collect_node);
1013 if (unlikely(err))
1014 goto break_or_fail;
1015
1016 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1017 err = nilfs_segctor_apply_buffers(
1018 sci, inode, &node_buffers, sc_ops->collect_bmap);
1019 if (unlikely(err))
1020 goto break_or_fail;
1021
1022 nilfs_segctor_end_finfo(sci, inode);
1023 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1024
1025 break_or_fail:
1026 return err;
1027}
1028
1029static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1030 struct inode *inode)
1031{
1032 LIST_HEAD(data_buffers);
1033 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1034 int err;
1035
1036 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1037 sci->sc_dsync_start,
1038 sci->sc_dsync_end);
1039
1040 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1041 nilfs_collect_file_data);
1042 if (!err) {
1043 nilfs_segctor_end_finfo(sci, inode);
1044 BUG_ON(n > rest);
1045 /* always receive -E2BIG or true error if n > rest */
1046 }
1047 return err;
1048}
1049
1050static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1051{
1052 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1053 struct list_head *head;
1054 struct nilfs_inode_info *ii;
1055 size_t ndone;
1056 int err = 0;
1057
1058 switch (sci->sc_stage.scnt) {
1059 case NILFS_ST_INIT:
1060 /* Pre-processes */
1061 sci->sc_stage.flags = 0;
1062
1063 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1064 sci->sc_nblk_inc = 0;
1065 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1066 if (mode == SC_LSEG_DSYNC) {
1067 sci->sc_stage.scnt = NILFS_ST_DSYNC;
1068 goto dsync_mode;
1069 }
1070 }
1071
1072 sci->sc_stage.dirty_file_ptr = NULL;
1073 sci->sc_stage.gc_inode_ptr = NULL;
1074 if (mode == SC_FLUSH_DAT) {
1075 sci->sc_stage.scnt = NILFS_ST_DAT;
1076 goto dat_stage;
1077 }
1078 sci->sc_stage.scnt++; /* Fall through */
1079 case NILFS_ST_GC:
1080 if (nilfs_doing_gc()) {
1081 head = &sci->sc_gc_inodes;
1082 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1083 head, i_dirty);
1084 list_for_each_entry_continue(ii, head, i_dirty) {
1085 err = nilfs_segctor_scan_file(
1086 sci, &ii->vfs_inode,
1087 &nilfs_sc_file_ops);
1088 if (unlikely(err)) {
1089 sci->sc_stage.gc_inode_ptr = list_entry(
1090 ii->i_dirty.prev,
1091 struct nilfs_inode_info,
1092 i_dirty);
1093 goto break_or_fail;
1094 }
1095 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1096 }
1097 sci->sc_stage.gc_inode_ptr = NULL;
1098 }
1099 sci->sc_stage.scnt++; /* Fall through */
1100 case NILFS_ST_FILE:
1101 head = &sci->sc_dirty_files;
1102 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1103 i_dirty);
1104 list_for_each_entry_continue(ii, head, i_dirty) {
1105 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1106
1107 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1108 &nilfs_sc_file_ops);
1109 if (unlikely(err)) {
1110 sci->sc_stage.dirty_file_ptr =
1111 list_entry(ii->i_dirty.prev,
1112 struct nilfs_inode_info,
1113 i_dirty);
1114 goto break_or_fail;
1115 }
1116 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1117 /* XXX: required ? */
1118 }
1119 sci->sc_stage.dirty_file_ptr = NULL;
1120 if (mode == SC_FLUSH_FILE) {
1121 sci->sc_stage.scnt = NILFS_ST_DONE;
1122 return 0;
1123 }
1124 sci->sc_stage.scnt++;
1125 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1126 /* Fall through */
1127 case NILFS_ST_IFILE:
1128 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1129 &nilfs_sc_file_ops);
1130 if (unlikely(err))
1131 break;
1132 sci->sc_stage.scnt++;
1133 /* Creating a checkpoint */
1134 err = nilfs_segctor_create_checkpoint(sci);
1135 if (unlikely(err))
1136 break;
1137 /* Fall through */
1138 case NILFS_ST_CPFILE:
1139 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1140 &nilfs_sc_file_ops);
1141 if (unlikely(err))
1142 break;
1143 sci->sc_stage.scnt++; /* Fall through */
1144 case NILFS_ST_SUFILE:
1145 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1146 sci->sc_nfreesegs, &ndone);
1147 if (unlikely(err)) {
1148 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1149 sci->sc_freesegs, ndone,
1150 NULL);
1151 break;
1152 }
1153 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1154
1155 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1156 &nilfs_sc_file_ops);
1157 if (unlikely(err))
1158 break;
1159 sci->sc_stage.scnt++; /* Fall through */
1160 case NILFS_ST_DAT:
1161 dat_stage:
1162 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1163 &nilfs_sc_dat_ops);
1164 if (unlikely(err))
1165 break;
1166 if (mode == SC_FLUSH_DAT) {
1167 sci->sc_stage.scnt = NILFS_ST_DONE;
1168 return 0;
1169 }
1170 sci->sc_stage.scnt++; /* Fall through */
1171 case NILFS_ST_SR:
1172 if (mode == SC_LSEG_SR) {
1173 /* Appending a super root */
1174 err = nilfs_segctor_add_super_root(sci);
1175 if (unlikely(err))
1176 break;
1177 }
1178 /* End of a logical segment */
1179 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1180 sci->sc_stage.scnt = NILFS_ST_DONE;
1181 return 0;
1182 case NILFS_ST_DSYNC:
1183 dsync_mode:
1184 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1185 ii = sci->sc_dsync_inode;
1186 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1187 break;
1188
1189 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1190 if (unlikely(err))
1191 break;
1192 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1193 sci->sc_stage.scnt = NILFS_ST_DONE;
1194 return 0;
1195 case NILFS_ST_DONE:
1196 return 0;
1197 default:
1198 BUG();
1199 }
1200
1201 break_or_fail:
1202 return err;
1203}
1204
1205/**
1206 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1207 * @sci: nilfs_sc_info
1208 * @nilfs: nilfs object
1209 */
1210static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1211 struct the_nilfs *nilfs)
1212{
1213 struct nilfs_segment_buffer *segbuf, *prev;
1214 __u64 nextnum;
1215 int err, alloc = 0;
1216
1217 segbuf = nilfs_segbuf_new(sci->sc_super);
1218 if (unlikely(!segbuf))
1219 return -ENOMEM;
1220
1221 if (list_empty(&sci->sc_write_logs)) {
1222 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1223 nilfs->ns_pseg_offset, nilfs);
1224 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1225 nilfs_shift_to_next_segment(nilfs);
1226 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1227 }
1228
1229 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1230 nextnum = nilfs->ns_nextnum;
1231
1232 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1233 /* Start from the head of a new full segment */
1234 alloc++;
1235 } else {
1236 /* Continue logs */
1237 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1238 nilfs_segbuf_map_cont(segbuf, prev);
1239 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1240 nextnum = prev->sb_nextnum;
1241
1242 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1243 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1244 segbuf->sb_sum.seg_seq++;
1245 alloc++;
1246 }
1247 }
1248
1249 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1250 if (err)
1251 goto failed;
1252
1253 if (alloc) {
1254 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1255 if (err)
1256 goto failed;
1257 }
1258 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1259
1260 BUG_ON(!list_empty(&sci->sc_segbufs));
1261 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1262 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1263 return 0;
1264
1265 failed:
1266 nilfs_segbuf_free(segbuf);
1267 return err;
1268}
1269
1270static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1271 struct the_nilfs *nilfs, int nadd)
1272{
1273 struct nilfs_segment_buffer *segbuf, *prev;
1274 struct inode *sufile = nilfs->ns_sufile;
1275 __u64 nextnextnum;
1276 LIST_HEAD(list);
1277 int err, ret, i;
1278
1279 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1280 /*
1281 * Since the segment specified with nextnum might be allocated during
1282 * the previous construction, the buffer including its segusage may
1283 * not be dirty. The following call ensures that the buffer is dirty
1284 * and will pin the buffer on memory until the sufile is written.
1285 */
1286 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1287 if (unlikely(err))
1288 return err;
1289
1290 for (i = 0; i < nadd; i++) {
1291 /* extend segment info */
1292 err = -ENOMEM;
1293 segbuf = nilfs_segbuf_new(sci->sc_super);
1294 if (unlikely(!segbuf))
1295 goto failed;
1296
1297 /* map this buffer to region of segment on-disk */
1298 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1299 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1300
1301 /* allocate the next next full segment */
1302 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1303 if (unlikely(err))
1304 goto failed_segbuf;
1305
1306 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1307 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1308
1309 list_add_tail(&segbuf->sb_list, &list);
1310 prev = segbuf;
1311 }
1312 list_splice_tail(&list, &sci->sc_segbufs);
1313 return 0;
1314
1315 failed_segbuf:
1316 nilfs_segbuf_free(segbuf);
1317 failed:
1318 list_for_each_entry(segbuf, &list, sb_list) {
1319 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1320 WARN_ON(ret); /* never fails */
1321 }
1322 nilfs_destroy_logs(&list);
1323 return err;
1324}
1325
1326static void nilfs_free_incomplete_logs(struct list_head *logs,
1327 struct the_nilfs *nilfs)
1328{
1329 struct nilfs_segment_buffer *segbuf, *prev;
1330 struct inode *sufile = nilfs->ns_sufile;
1331 int ret;
1332
1333 segbuf = NILFS_FIRST_SEGBUF(logs);
1334 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1335 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1336 WARN_ON(ret); /* never fails */
1337 }
1338 if (atomic_read(&segbuf->sb_err)) {
1339 /* Case 1: The first segment failed */
1340 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1341 /* Case 1a: Partial segment appended into an existing
1342 segment */
1343 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1344 segbuf->sb_fseg_end);
1345 else /* Case 1b: New full segment */
1346 set_nilfs_discontinued(nilfs);
1347 }
1348
1349 prev = segbuf;
1350 list_for_each_entry_continue(segbuf, logs, sb_list) {
1351 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1352 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1353 WARN_ON(ret); /* never fails */
1354 }
1355 if (atomic_read(&segbuf->sb_err) &&
1356 segbuf->sb_segnum != nilfs->ns_nextnum)
1357 /* Case 2: extended segment (!= next) failed */
1358 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1359 prev = segbuf;
1360 }
1361}
1362
1363static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1364 struct inode *sufile)
1365{
1366 struct nilfs_segment_buffer *segbuf;
1367 unsigned long live_blocks;
1368 int ret;
1369
1370 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1371 live_blocks = segbuf->sb_sum.nblocks +
1372 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1373 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1374 live_blocks,
1375 sci->sc_seg_ctime);
1376 WARN_ON(ret); /* always succeed because the segusage is dirty */
1377 }
1378}
1379
1380static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1381{
1382 struct nilfs_segment_buffer *segbuf;
1383 int ret;
1384
1385 segbuf = NILFS_FIRST_SEGBUF(logs);
1386 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1387 segbuf->sb_pseg_start -
1388 segbuf->sb_fseg_start, 0);
1389 WARN_ON(ret); /* always succeed because the segusage is dirty */
1390
1391 list_for_each_entry_continue(segbuf, logs, sb_list) {
1392 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1393 0, 0);
1394 WARN_ON(ret); /* always succeed */
1395 }
1396}
1397
1398static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1399 struct nilfs_segment_buffer *last,
1400 struct inode *sufile)
1401{
1402 struct nilfs_segment_buffer *segbuf = last;
1403 int ret;
1404
1405 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1406 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1407 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1408 WARN_ON(ret);
1409 }
1410 nilfs_truncate_logs(&sci->sc_segbufs, last);
1411}
1412
1413
1414static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1415 struct the_nilfs *nilfs, int mode)
1416{
1417 struct nilfs_cstage prev_stage = sci->sc_stage;
1418 int err, nadd = 1;
1419
1420 /* Collection retry loop */
1421 for (;;) {
1422 sci->sc_nblk_this_inc = 0;
1423 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1424
1425 err = nilfs_segctor_reset_segment_buffer(sci);
1426 if (unlikely(err))
1427 goto failed;
1428
1429 err = nilfs_segctor_collect_blocks(sci, mode);
1430 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1431 if (!err)
1432 break;
1433
1434 if (unlikely(err != -E2BIG))
1435 goto failed;
1436
1437 /* The current segment is filled up */
1438 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE)
1439 break;
1440
1441 nilfs_clear_logs(&sci->sc_segbufs);
1442
1443 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1444 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1445 sci->sc_freesegs,
1446 sci->sc_nfreesegs,
1447 NULL);
1448 WARN_ON(err); /* do not happen */
1449 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1450 }
1451
1452 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1453 if (unlikely(err))
1454 return err;
1455
1456 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1457 sci->sc_stage = prev_stage;
1458 }
1459 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1460 return 0;
1461
1462 failed:
1463 return err;
1464}
1465
1466static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1467 struct buffer_head *new_bh)
1468{
1469 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1470
1471 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1472 /* The caller must release old_bh */
1473}
1474
1475static int
1476nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1477 struct nilfs_segment_buffer *segbuf,
1478 int mode)
1479{
1480 struct inode *inode = NULL;
1481 sector_t blocknr;
1482 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1483 unsigned long nblocks = 0, ndatablk = 0;
1484 struct nilfs_sc_operations *sc_op = NULL;
1485 struct nilfs_segsum_pointer ssp;
1486 struct nilfs_finfo *finfo = NULL;
1487 union nilfs_binfo binfo;
1488 struct buffer_head *bh, *bh_org;
1489 ino_t ino = 0;
1490 int err = 0;
1491
1492 if (!nfinfo)
1493 goto out;
1494
1495 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1496 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1497 ssp.offset = sizeof(struct nilfs_segment_summary);
1498
1499 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1500 if (bh == segbuf->sb_super_root)
1501 break;
1502 if (!finfo) {
1503 finfo = nilfs_segctor_map_segsum_entry(
1504 sci, &ssp, sizeof(*finfo));
1505 ino = le64_to_cpu(finfo->fi_ino);
1506 nblocks = le32_to_cpu(finfo->fi_nblocks);
1507 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1508
1509 inode = bh->b_page->mapping->host;
1510
1511 if (mode == SC_LSEG_DSYNC)
1512 sc_op = &nilfs_sc_dsync_ops;
1513 else if (ino == NILFS_DAT_INO)
1514 sc_op = &nilfs_sc_dat_ops;
1515 else /* file blocks */
1516 sc_op = &nilfs_sc_file_ops;
1517 }
1518 bh_org = bh;
1519 get_bh(bh_org);
1520 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1521 &binfo);
1522 if (bh != bh_org)
1523 nilfs_list_replace_buffer(bh_org, bh);
1524 brelse(bh_org);
1525 if (unlikely(err))
1526 goto failed_bmap;
1527
1528 if (ndatablk > 0)
1529 sc_op->write_data_binfo(sci, &ssp, &binfo);
1530 else
1531 sc_op->write_node_binfo(sci, &ssp, &binfo);
1532
1533 blocknr++;
1534 if (--nblocks == 0) {
1535 finfo = NULL;
1536 if (--nfinfo == 0)
1537 break;
1538 } else if (ndatablk > 0)
1539 ndatablk--;
1540 }
1541 out:
1542 return 0;
1543
1544 failed_bmap:
1545 return err;
1546}
1547
1548static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1549{
1550 struct nilfs_segment_buffer *segbuf;
1551 int err;
1552
1553 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1554 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1555 if (unlikely(err))
1556 return err;
1557 nilfs_segbuf_fill_in_segsum(segbuf);
1558 }
1559 return 0;
1560}
1561
1562static void nilfs_begin_page_io(struct page *page)
1563{
1564 if (!page || PageWriteback(page))
1565 /* For split b-tree node pages, this function may be called
1566 twice. We ignore the 2nd or later calls by this check. */
1567 return;
1568
1569 lock_page(page);
1570 clear_page_dirty_for_io(page);
1571 set_page_writeback(page);
1572 unlock_page(page);
1573}
1574
1575static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1576{
1577 struct nilfs_segment_buffer *segbuf;
1578 struct page *bd_page = NULL, *fs_page = NULL;
1579
1580 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1581 struct buffer_head *bh;
1582
1583 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1584 b_assoc_buffers) {
1585 set_buffer_async_write(bh);
1586 if (bh->b_page != bd_page) {
1587 if (bd_page) {
1588 lock_page(bd_page);
1589 clear_page_dirty_for_io(bd_page);
1590 set_page_writeback(bd_page);
1591 unlock_page(bd_page);
1592 }
1593 bd_page = bh->b_page;
1594 }
1595 }
1596
1597 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1598 b_assoc_buffers) {
1599 set_buffer_async_write(bh);
1600 if (bh == segbuf->sb_super_root) {
1601 if (bh->b_page != bd_page) {
1602 lock_page(bd_page);
1603 clear_page_dirty_for_io(bd_page);
1604 set_page_writeback(bd_page);
1605 unlock_page(bd_page);
1606 bd_page = bh->b_page;
1607 }
1608 break;
1609 }
1610 if (bh->b_page != fs_page) {
1611 nilfs_begin_page_io(fs_page);
1612 fs_page = bh->b_page;
1613 }
1614 }
1615 }
1616 if (bd_page) {
1617 lock_page(bd_page);
1618 clear_page_dirty_for_io(bd_page);
1619 set_page_writeback(bd_page);
1620 unlock_page(bd_page);
1621 }
1622 nilfs_begin_page_io(fs_page);
1623}
1624
1625static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1626 struct the_nilfs *nilfs)
1627{
1628 int ret;
1629
1630 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1631 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1632 return ret;
1633}
1634
1635static void nilfs_end_page_io(struct page *page, int err)
1636{
1637 if (!page)
1638 return;
1639
1640 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1641 /*
1642 * For b-tree node pages, this function may be called twice
1643 * or more because they might be split in a segment.
1644 */
1645 if (PageDirty(page)) {
1646 /*
1647 * For pages holding split b-tree node buffers, dirty
1648 * flag on the buffers may be cleared discretely.
1649 * In that case, the page is once redirtied for
1650 * remaining buffers, and it must be cancelled if
1651 * all the buffers get cleaned later.
1652 */
1653 lock_page(page);
1654 if (nilfs_page_buffers_clean(page))
1655 __nilfs_clear_page_dirty(page);
1656 unlock_page(page);
1657 }
1658 return;
1659 }
1660
1661 if (!err) {
1662 if (!nilfs_page_buffers_clean(page))
1663 __set_page_dirty_nobuffers(page);
1664 ClearPageError(page);
1665 } else {
1666 __set_page_dirty_nobuffers(page);
1667 SetPageError(page);
1668 }
1669
1670 end_page_writeback(page);
1671}
1672
1673static void nilfs_abort_logs(struct list_head *logs, int err)
1674{
1675 struct nilfs_segment_buffer *segbuf;
1676 struct page *bd_page = NULL, *fs_page = NULL;
1677 struct buffer_head *bh;
1678
1679 if (list_empty(logs))
1680 return;
1681
1682 list_for_each_entry(segbuf, logs, sb_list) {
1683 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1684 b_assoc_buffers) {
1685 clear_buffer_async_write(bh);
1686 if (bh->b_page != bd_page) {
1687 if (bd_page)
1688 end_page_writeback(bd_page);
1689 bd_page = bh->b_page;
1690 }
1691 }
1692
1693 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1694 b_assoc_buffers) {
1695 clear_buffer_async_write(bh);
1696 if (bh == segbuf->sb_super_root) {
1697 if (bh->b_page != bd_page) {
1698 end_page_writeback(bd_page);
1699 bd_page = bh->b_page;
1700 }
1701 break;
1702 }
1703 if (bh->b_page != fs_page) {
1704 nilfs_end_page_io(fs_page, err);
1705 fs_page = bh->b_page;
1706 }
1707 }
1708 }
1709 if (bd_page)
1710 end_page_writeback(bd_page);
1711
1712 nilfs_end_page_io(fs_page, err);
1713}
1714
1715static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1716 struct the_nilfs *nilfs, int err)
1717{
1718 LIST_HEAD(logs);
1719 int ret;
1720
1721 list_splice_tail_init(&sci->sc_write_logs, &logs);
1722 ret = nilfs_wait_on_logs(&logs);
1723 nilfs_abort_logs(&logs, ret ? : err);
1724
1725 list_splice_tail_init(&sci->sc_segbufs, &logs);
1726 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1727 nilfs_free_incomplete_logs(&logs, nilfs);
1728
1729 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1730 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1731 sci->sc_freesegs,
1732 sci->sc_nfreesegs,
1733 NULL);
1734 WARN_ON(ret); /* do not happen */
1735 }
1736
1737 nilfs_destroy_logs(&logs);
1738}
1739
1740static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1741 struct nilfs_segment_buffer *segbuf)
1742{
1743 nilfs->ns_segnum = segbuf->sb_segnum;
1744 nilfs->ns_nextnum = segbuf->sb_nextnum;
1745 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1746 + segbuf->sb_sum.nblocks;
1747 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1748 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1749}
1750
1751static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1752{
1753 struct nilfs_segment_buffer *segbuf;
1754 struct page *bd_page = NULL, *fs_page = NULL;
1755 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1756 int update_sr = false;
1757
1758 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1759 struct buffer_head *bh;
1760
1761 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1762 b_assoc_buffers) {
1763 set_buffer_uptodate(bh);
1764 clear_buffer_dirty(bh);
1765 clear_buffer_async_write(bh);
1766 if (bh->b_page != bd_page) {
1767 if (bd_page)
1768 end_page_writeback(bd_page);
1769 bd_page = bh->b_page;
1770 }
1771 }
1772 /*
1773 * We assume that the buffers which belong to the same page
1774 * continue over the buffer list.
1775 * Under this assumption, the last BHs of pages is
1776 * identifiable by the discontinuity of bh->b_page
1777 * (page != fs_page).
1778 *
1779 * For B-tree node blocks, however, this assumption is not
1780 * guaranteed. The cleanup code of B-tree node pages needs
1781 * special care.
1782 */
1783 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1784 b_assoc_buffers) {
1785 set_buffer_uptodate(bh);
1786 clear_buffer_dirty(bh);
1787 clear_buffer_async_write(bh);
1788 clear_buffer_delay(bh);
1789 clear_buffer_nilfs_volatile(bh);
1790 clear_buffer_nilfs_redirected(bh);
1791 if (bh == segbuf->sb_super_root) {
1792 if (bh->b_page != bd_page) {
1793 end_page_writeback(bd_page);
1794 bd_page = bh->b_page;
1795 }
1796 update_sr = true;
1797 break;
1798 }
1799 if (bh->b_page != fs_page) {
1800 nilfs_end_page_io(fs_page, 0);
1801 fs_page = bh->b_page;
1802 }
1803 }
1804
1805 if (!nilfs_segbuf_simplex(segbuf)) {
1806 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1807 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1808 sci->sc_lseg_stime = jiffies;
1809 }
1810 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1811 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1812 }
1813 }
1814 /*
1815 * Since pages may continue over multiple segment buffers,
1816 * end of the last page must be checked outside of the loop.
1817 */
1818 if (bd_page)
1819 end_page_writeback(bd_page);
1820
1821 nilfs_end_page_io(fs_page, 0);
1822
1823 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1824
1825 if (nilfs_doing_gc())
1826 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1827 else
1828 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1829
1830 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1831
1832 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1833 nilfs_set_next_segment(nilfs, segbuf);
1834
1835 if (update_sr) {
1836 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1837 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1838
1839 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1840 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1841 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1842 nilfs_segctor_clear_metadata_dirty(sci);
1843 } else
1844 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1845}
1846
1847static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1848{
1849 int ret;
1850
1851 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1852 if (!ret) {
1853 nilfs_segctor_complete_write(sci);
1854 nilfs_destroy_logs(&sci->sc_write_logs);
1855 }
1856 return ret;
1857}
1858
1859static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1860 struct the_nilfs *nilfs)
1861{
1862 struct nilfs_inode_info *ii, *n;
1863 struct inode *ifile = sci->sc_root->ifile;
1864
1865 spin_lock(&nilfs->ns_inode_lock);
1866 retry:
1867 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1868 if (!ii->i_bh) {
1869 struct buffer_head *ibh;
1870 int err;
1871
1872 spin_unlock(&nilfs->ns_inode_lock);
1873 err = nilfs_ifile_get_inode_block(
1874 ifile, ii->vfs_inode.i_ino, &ibh);
1875 if (unlikely(err)) {
1876 nilfs_warning(sci->sc_super, __func__,
1877 "failed to get inode block.\n");
1878 return err;
1879 }
1880 mark_buffer_dirty(ibh);
1881 nilfs_mdt_mark_dirty(ifile);
1882 spin_lock(&nilfs->ns_inode_lock);
1883 if (likely(!ii->i_bh))
1884 ii->i_bh = ibh;
1885 else
1886 brelse(ibh);
1887 goto retry;
1888 }
1889
1890 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1891 set_bit(NILFS_I_BUSY, &ii->i_state);
1892 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1893 }
1894 spin_unlock(&nilfs->ns_inode_lock);
1895
1896 return 0;
1897}
1898
1899static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1900 struct the_nilfs *nilfs)
1901{
1902 struct nilfs_transaction_info *ti = current->journal_info;
1903 struct nilfs_inode_info *ii, *n;
1904
1905 spin_lock(&nilfs->ns_inode_lock);
1906 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1907 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1908 test_bit(NILFS_I_DIRTY, &ii->i_state))
1909 continue;
1910
1911 clear_bit(NILFS_I_BUSY, &ii->i_state);
1912 brelse(ii->i_bh);
1913 ii->i_bh = NULL;
1914 list_move_tail(&ii->i_dirty, &ti->ti_garbage);
1915 }
1916 spin_unlock(&nilfs->ns_inode_lock);
1917}
1918
1919/*
1920 * Main procedure of segment constructor
1921 */
1922static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
1923{
1924 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1925 int err;
1926
1927 sci->sc_stage.scnt = NILFS_ST_INIT;
1928 sci->sc_cno = nilfs->ns_cno;
1929
1930 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
1931 if (unlikely(err))
1932 goto out;
1933
1934 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
1935 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1936
1937 if (nilfs_segctor_clean(sci))
1938 goto out;
1939
1940 do {
1941 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
1942
1943 err = nilfs_segctor_begin_construction(sci, nilfs);
1944 if (unlikely(err))
1945 goto out;
1946
1947 /* Update time stamp */
1948 sci->sc_seg_ctime = get_seconds();
1949
1950 err = nilfs_segctor_collect(sci, nilfs, mode);
1951 if (unlikely(err))
1952 goto failed;
1953
1954 /* Avoid empty segment */
1955 if (sci->sc_stage.scnt == NILFS_ST_DONE &&
1956 nilfs_segbuf_empty(sci->sc_curseg)) {
1957 nilfs_segctor_abort_construction(sci, nilfs, 1);
1958 goto out;
1959 }
1960
1961 err = nilfs_segctor_assign(sci, mode);
1962 if (unlikely(err))
1963 goto failed;
1964
1965 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
1966 nilfs_segctor_fill_in_file_bmap(sci);
1967
1968 if (mode == SC_LSEG_SR &&
1969 sci->sc_stage.scnt >= NILFS_ST_CPFILE) {
1970 err = nilfs_segctor_fill_in_checkpoint(sci);
1971 if (unlikely(err))
1972 goto failed_to_write;
1973
1974 nilfs_segctor_fill_in_super_root(sci, nilfs);
1975 }
1976 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
1977
1978 /* Write partial segments */
1979 nilfs_segctor_prepare_write(sci);
1980
1981 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
1982 nilfs->ns_crc_seed);
1983
1984 err = nilfs_segctor_write(sci, nilfs);
1985 if (unlikely(err))
1986 goto failed_to_write;
1987
1988 if (sci->sc_stage.scnt == NILFS_ST_DONE ||
1989 nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) {
1990 /*
1991 * At this point, we avoid double buffering
1992 * for blocksize < pagesize because page dirty
1993 * flag is turned off during write and dirty
1994 * buffers are not properly collected for
1995 * pages crossing over segments.
1996 */
1997 err = nilfs_segctor_wait(sci);
1998 if (err)
1999 goto failed_to_write;
2000 }
2001 } while (sci->sc_stage.scnt != NILFS_ST_DONE);
2002
2003 out:
2004 nilfs_segctor_drop_written_files(sci, nilfs);
2005 return err;
2006
2007 failed_to_write:
2008 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2009 nilfs_redirty_inodes(&sci->sc_dirty_files);
2010
2011 failed:
2012 if (nilfs_doing_gc())
2013 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2014 nilfs_segctor_abort_construction(sci, nilfs, err);
2015 goto out;
2016}
2017
2018/**
2019 * nilfs_segctor_start_timer - set timer of background write
2020 * @sci: nilfs_sc_info
2021 *
2022 * If the timer has already been set, it ignores the new request.
2023 * This function MUST be called within a section locking the segment
2024 * semaphore.
2025 */
2026static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2027{
2028 spin_lock(&sci->sc_state_lock);
2029 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2030 sci->sc_timer.expires = jiffies + sci->sc_interval;
2031 add_timer(&sci->sc_timer);
2032 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2033 }
2034 spin_unlock(&sci->sc_state_lock);
2035}
2036
2037static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2038{
2039 spin_lock(&sci->sc_state_lock);
2040 if (!(sci->sc_flush_request & (1 << bn))) {
2041 unsigned long prev_req = sci->sc_flush_request;
2042
2043 sci->sc_flush_request |= (1 << bn);
2044 if (!prev_req)
2045 wake_up(&sci->sc_wait_daemon);
2046 }
2047 spin_unlock(&sci->sc_state_lock);
2048}
2049
2050/**
2051 * nilfs_flush_segment - trigger a segment construction for resource control
2052 * @sb: super block
2053 * @ino: inode number of the file to be flushed out.
2054 */
2055void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2056{
2057 struct the_nilfs *nilfs = sb->s_fs_info;
2058 struct nilfs_sc_info *sci = nilfs->ns_writer;
2059
2060 if (!sci || nilfs_doing_construction())
2061 return;
2062 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2063 /* assign bit 0 to data files */
2064}
2065
2066struct nilfs_segctor_wait_request {
2067 wait_queue_t wq;
2068 __u32 seq;
2069 int err;
2070 atomic_t done;
2071};
2072
2073static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2074{
2075 struct nilfs_segctor_wait_request wait_req;
2076 int err = 0;
2077
2078 spin_lock(&sci->sc_state_lock);
2079 init_wait(&wait_req.wq);
2080 wait_req.err = 0;
2081 atomic_set(&wait_req.done, 0);
2082 wait_req.seq = ++sci->sc_seq_request;
2083 spin_unlock(&sci->sc_state_lock);
2084
2085 init_waitqueue_entry(&wait_req.wq, current);
2086 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2087 set_current_state(TASK_INTERRUPTIBLE);
2088 wake_up(&sci->sc_wait_daemon);
2089
2090 for (;;) {
2091 if (atomic_read(&wait_req.done)) {
2092 err = wait_req.err;
2093 break;
2094 }
2095 if (!signal_pending(current)) {
2096 schedule();
2097 continue;
2098 }
2099 err = -ERESTARTSYS;
2100 break;
2101 }
2102 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2103 return err;
2104}
2105
2106static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2107{
2108 struct nilfs_segctor_wait_request *wrq, *n;
2109 unsigned long flags;
2110
2111 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2112 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2113 wq.task_list) {
2114 if (!atomic_read(&wrq->done) &&
2115 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2116 wrq->err = err;
2117 atomic_set(&wrq->done, 1);
2118 }
2119 if (atomic_read(&wrq->done)) {
2120 wrq->wq.func(&wrq->wq,
2121 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2122 0, NULL);
2123 }
2124 }
2125 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2126}
2127
2128/**
2129 * nilfs_construct_segment - construct a logical segment
2130 * @sb: super block
2131 *
2132 * Return Value: On success, 0 is retured. On errors, one of the following
2133 * negative error code is returned.
2134 *
2135 * %-EROFS - Read only filesystem.
2136 *
2137 * %-EIO - I/O error
2138 *
2139 * %-ENOSPC - No space left on device (only in a panic state).
2140 *
2141 * %-ERESTARTSYS - Interrupted.
2142 *
2143 * %-ENOMEM - Insufficient memory available.
2144 */
2145int nilfs_construct_segment(struct super_block *sb)
2146{
2147 struct the_nilfs *nilfs = sb->s_fs_info;
2148 struct nilfs_sc_info *sci = nilfs->ns_writer;
2149 struct nilfs_transaction_info *ti;
2150 int err;
2151
2152 if (!sci)
2153 return -EROFS;
2154
2155 /* A call inside transactions causes a deadlock. */
2156 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2157
2158 err = nilfs_segctor_sync(sci);
2159 return err;
2160}
2161
2162/**
2163 * nilfs_construct_dsync_segment - construct a data-only logical segment
2164 * @sb: super block
2165 * @inode: inode whose data blocks should be written out
2166 * @start: start byte offset
2167 * @end: end byte offset (inclusive)
2168 *
2169 * Return Value: On success, 0 is retured. On errors, one of the following
2170 * negative error code is returned.
2171 *
2172 * %-EROFS - Read only filesystem.
2173 *
2174 * %-EIO - I/O error
2175 *
2176 * %-ENOSPC - No space left on device (only in a panic state).
2177 *
2178 * %-ERESTARTSYS - Interrupted.
2179 *
2180 * %-ENOMEM - Insufficient memory available.
2181 */
2182int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2183 loff_t start, loff_t end)
2184{
2185 struct the_nilfs *nilfs = sb->s_fs_info;
2186 struct nilfs_sc_info *sci = nilfs->ns_writer;
2187 struct nilfs_inode_info *ii;
2188 struct nilfs_transaction_info ti;
2189 int err = 0;
2190
2191 if (!sci)
2192 return -EROFS;
2193
2194 nilfs_transaction_lock(sb, &ti, 0);
2195
2196 ii = NILFS_I(inode);
2197 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) ||
2198 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2199 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2200 nilfs_discontinued(nilfs)) {
2201 nilfs_transaction_unlock(sb);
2202 err = nilfs_segctor_sync(sci);
2203 return err;
2204 }
2205
2206 spin_lock(&nilfs->ns_inode_lock);
2207 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2208 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2209 spin_unlock(&nilfs->ns_inode_lock);
2210 nilfs_transaction_unlock(sb);
2211 return 0;
2212 }
2213 spin_unlock(&nilfs->ns_inode_lock);
2214 sci->sc_dsync_inode = ii;
2215 sci->sc_dsync_start = start;
2216 sci->sc_dsync_end = end;
2217
2218 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2219
2220 nilfs_transaction_unlock(sb);
2221 return err;
2222}
2223
2224#define FLUSH_FILE_BIT (0x1) /* data file only */
2225#define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2226
2227/**
2228 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2229 * @sci: segment constructor object
2230 */
2231static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2232{
2233 spin_lock(&sci->sc_state_lock);
2234 sci->sc_seq_accepted = sci->sc_seq_request;
2235 spin_unlock(&sci->sc_state_lock);
2236 del_timer_sync(&sci->sc_timer);
2237}
2238
2239/**
2240 * nilfs_segctor_notify - notify the result of request to caller threads
2241 * @sci: segment constructor object
2242 * @mode: mode of log forming
2243 * @err: error code to be notified
2244 */
2245static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2246{
2247 /* Clear requests (even when the construction failed) */
2248 spin_lock(&sci->sc_state_lock);
2249
2250 if (mode == SC_LSEG_SR) {
2251 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2252 sci->sc_seq_done = sci->sc_seq_accepted;
2253 nilfs_segctor_wakeup(sci, err);
2254 sci->sc_flush_request = 0;
2255 } else {
2256 if (mode == SC_FLUSH_FILE)
2257 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2258 else if (mode == SC_FLUSH_DAT)
2259 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2260
2261 /* re-enable timer if checkpoint creation was not done */
2262 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2263 time_before(jiffies, sci->sc_timer.expires))
2264 add_timer(&sci->sc_timer);
2265 }
2266 spin_unlock(&sci->sc_state_lock);
2267}
2268
2269/**
2270 * nilfs_segctor_construct - form logs and write them to disk
2271 * @sci: segment constructor object
2272 * @mode: mode of log forming
2273 */
2274static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2275{
2276 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2277 struct nilfs_super_block **sbp;
2278 int err = 0;
2279
2280 nilfs_segctor_accept(sci);
2281
2282 if (nilfs_discontinued(nilfs))
2283 mode = SC_LSEG_SR;
2284 if (!nilfs_segctor_confirm(sci))
2285 err = nilfs_segctor_do_construct(sci, mode);
2286
2287 if (likely(!err)) {
2288 if (mode != SC_FLUSH_DAT)
2289 atomic_set(&nilfs->ns_ndirtyblks, 0);
2290 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2291 nilfs_discontinued(nilfs)) {
2292 down_write(&nilfs->ns_sem);
2293 err = -EIO;
2294 sbp = nilfs_prepare_super(sci->sc_super,
2295 nilfs_sb_will_flip(nilfs));
2296 if (likely(sbp)) {
2297 nilfs_set_log_cursor(sbp[0], nilfs);
2298 err = nilfs_commit_super(sci->sc_super,
2299 NILFS_SB_COMMIT);
2300 }
2301 up_write(&nilfs->ns_sem);
2302 }
2303 }
2304
2305 nilfs_segctor_notify(sci, mode, err);
2306 return err;
2307}
2308
2309static void nilfs_construction_timeout(unsigned long data)
2310{
2311 struct task_struct *p = (struct task_struct *)data;
2312 wake_up_process(p);
2313}
2314
2315static void
2316nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2317{
2318 struct nilfs_inode_info *ii, *n;
2319
2320 list_for_each_entry_safe(ii, n, head, i_dirty) {
2321 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2322 continue;
2323 list_del_init(&ii->i_dirty);
2324 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2325 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2326 iput(&ii->vfs_inode);
2327 }
2328}
2329
2330int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2331 void **kbufs)
2332{
2333 struct the_nilfs *nilfs = sb->s_fs_info;
2334 struct nilfs_sc_info *sci = nilfs->ns_writer;
2335 struct nilfs_transaction_info ti;
2336 int err;
2337
2338 if (unlikely(!sci))
2339 return -EROFS;
2340
2341 nilfs_transaction_lock(sb, &ti, 1);
2342
2343 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2344 if (unlikely(err))
2345 goto out_unlock;
2346
2347 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2348 if (unlikely(err)) {
2349 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2350 goto out_unlock;
2351 }
2352
2353 sci->sc_freesegs = kbufs[4];
2354 sci->sc_nfreesegs = argv[4].v_nmembs;
2355 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2356
2357 for (;;) {
2358 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2359 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2360
2361 if (likely(!err))
2362 break;
2363
2364 nilfs_warning(sb, __func__,
2365 "segment construction failed. (err=%d)", err);
2366 set_current_state(TASK_INTERRUPTIBLE);
2367 schedule_timeout(sci->sc_interval);
2368 }
2369 if (nilfs_test_opt(nilfs, DISCARD)) {
2370 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2371 sci->sc_nfreesegs);
2372 if (ret) {
2373 printk(KERN_WARNING
2374 "NILFS warning: error %d on discard request, "
2375 "turning discards off for the device\n", ret);
2376 nilfs_clear_opt(nilfs, DISCARD);
2377 }
2378 }
2379
2380 out_unlock:
2381 sci->sc_freesegs = NULL;
2382 sci->sc_nfreesegs = 0;
2383 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2384 nilfs_transaction_unlock(sb);
2385 return err;
2386}
2387
2388static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2389{
2390 struct nilfs_transaction_info ti;
2391
2392 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2393 nilfs_segctor_construct(sci, mode);
2394
2395 /*
2396 * Unclosed segment should be retried. We do this using sc_timer.
2397 * Timeout of sc_timer will invoke complete construction which leads
2398 * to close the current logical segment.
2399 */
2400 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2401 nilfs_segctor_start_timer(sci);
2402
2403 nilfs_transaction_unlock(sci->sc_super);
2404}
2405
2406static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2407{
2408 int mode = 0;
2409 int err;
2410
2411 spin_lock(&sci->sc_state_lock);
2412 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2413 SC_FLUSH_DAT : SC_FLUSH_FILE;
2414 spin_unlock(&sci->sc_state_lock);
2415
2416 if (mode) {
2417 err = nilfs_segctor_do_construct(sci, mode);
2418
2419 spin_lock(&sci->sc_state_lock);
2420 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2421 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2422 spin_unlock(&sci->sc_state_lock);
2423 }
2424 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2425}
2426
2427static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2428{
2429 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2430 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2431 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2432 return SC_FLUSH_FILE;
2433 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2434 return SC_FLUSH_DAT;
2435 }
2436 return SC_LSEG_SR;
2437}
2438
2439/**
2440 * nilfs_segctor_thread - main loop of the segment constructor thread.
2441 * @arg: pointer to a struct nilfs_sc_info.
2442 *
2443 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2444 * to execute segment constructions.
2445 */
2446static int nilfs_segctor_thread(void *arg)
2447{
2448 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2449 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2450 int timeout = 0;
2451
2452 sci->sc_timer.data = (unsigned long)current;
2453 sci->sc_timer.function = nilfs_construction_timeout;
2454
2455 /* start sync. */
2456 sci->sc_task = current;
2457 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2458 printk(KERN_INFO
2459 "segctord starting. Construction interval = %lu seconds, "
2460 "CP frequency < %lu seconds\n",
2461 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2462
2463 spin_lock(&sci->sc_state_lock);
2464 loop:
2465 for (;;) {
2466 int mode;
2467
2468 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2469 goto end_thread;
2470
2471 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2472 mode = SC_LSEG_SR;
2473 else if (!sci->sc_flush_request)
2474 break;
2475 else
2476 mode = nilfs_segctor_flush_mode(sci);
2477
2478 spin_unlock(&sci->sc_state_lock);
2479 nilfs_segctor_thread_construct(sci, mode);
2480 spin_lock(&sci->sc_state_lock);
2481 timeout = 0;
2482 }
2483
2484
2485 if (freezing(current)) {
2486 spin_unlock(&sci->sc_state_lock);
2487 try_to_freeze();
2488 spin_lock(&sci->sc_state_lock);
2489 } else {
2490 DEFINE_WAIT(wait);
2491 int should_sleep = 1;
2492
2493 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2494 TASK_INTERRUPTIBLE);
2495
2496 if (sci->sc_seq_request != sci->sc_seq_done)
2497 should_sleep = 0;
2498 else if (sci->sc_flush_request)
2499 should_sleep = 0;
2500 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2501 should_sleep = time_before(jiffies,
2502 sci->sc_timer.expires);
2503
2504 if (should_sleep) {
2505 spin_unlock(&sci->sc_state_lock);
2506 schedule();
2507 spin_lock(&sci->sc_state_lock);
2508 }
2509 finish_wait(&sci->sc_wait_daemon, &wait);
2510 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2511 time_after_eq(jiffies, sci->sc_timer.expires));
2512
2513 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2514 set_nilfs_discontinued(nilfs);
2515 }
2516 goto loop;
2517
2518 end_thread:
2519 spin_unlock(&sci->sc_state_lock);
2520
2521 /* end sync. */
2522 sci->sc_task = NULL;
2523 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2524 return 0;
2525}
2526
2527static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2528{
2529 struct task_struct *t;
2530
2531 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2532 if (IS_ERR(t)) {
2533 int err = PTR_ERR(t);
2534
2535 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2536 err);
2537 return err;
2538 }
2539 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2540 return 0;
2541}
2542
2543static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2544 __acquires(&sci->sc_state_lock)
2545 __releases(&sci->sc_state_lock)
2546{
2547 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2548
2549 while (sci->sc_task) {
2550 wake_up(&sci->sc_wait_daemon);
2551 spin_unlock(&sci->sc_state_lock);
2552 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2553 spin_lock(&sci->sc_state_lock);
2554 }
2555}
2556
2557/*
2558 * Setup & clean-up functions
2559 */
2560static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2561 struct nilfs_root *root)
2562{
2563 struct the_nilfs *nilfs = sb->s_fs_info;
2564 struct nilfs_sc_info *sci;
2565
2566 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2567 if (!sci)
2568 return NULL;
2569
2570 sci->sc_super = sb;
2571
2572 nilfs_get_root(root);
2573 sci->sc_root = root;
2574
2575 init_waitqueue_head(&sci->sc_wait_request);
2576 init_waitqueue_head(&sci->sc_wait_daemon);
2577 init_waitqueue_head(&sci->sc_wait_task);
2578 spin_lock_init(&sci->sc_state_lock);
2579 INIT_LIST_HEAD(&sci->sc_dirty_files);
2580 INIT_LIST_HEAD(&sci->sc_segbufs);
2581 INIT_LIST_HEAD(&sci->sc_write_logs);
2582 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2583 init_timer(&sci->sc_timer);
2584
2585 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2586 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2587 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2588
2589 if (nilfs->ns_interval)
2590 sci->sc_interval = HZ * nilfs->ns_interval;
2591 if (nilfs->ns_watermark)
2592 sci->sc_watermark = nilfs->ns_watermark;
2593 return sci;
2594}
2595
2596static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2597{
2598 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2599
2600 /* The segctord thread was stopped and its timer was removed.
2601 But some tasks remain. */
2602 do {
2603 struct nilfs_transaction_info ti;
2604
2605 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2606 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2607 nilfs_transaction_unlock(sci->sc_super);
2608
2609 } while (ret && retrycount-- > 0);
2610}
2611
2612/**
2613 * nilfs_segctor_destroy - destroy the segment constructor.
2614 * @sci: nilfs_sc_info
2615 *
2616 * nilfs_segctor_destroy() kills the segctord thread and frees
2617 * the nilfs_sc_info struct.
2618 * Caller must hold the segment semaphore.
2619 */
2620static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2621{
2622 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2623 int flag;
2624
2625 up_write(&nilfs->ns_segctor_sem);
2626
2627 spin_lock(&sci->sc_state_lock);
2628 nilfs_segctor_kill_thread(sci);
2629 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2630 || sci->sc_seq_request != sci->sc_seq_done);
2631 spin_unlock(&sci->sc_state_lock);
2632
2633 if (flag || !nilfs_segctor_confirm(sci))
2634 nilfs_segctor_write_out(sci);
2635
2636 if (!list_empty(&sci->sc_dirty_files)) {
2637 nilfs_warning(sci->sc_super, __func__,
2638 "dirty file(s) after the final construction\n");
2639 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2640 }
2641
2642 WARN_ON(!list_empty(&sci->sc_segbufs));
2643 WARN_ON(!list_empty(&sci->sc_write_logs));
2644
2645 nilfs_put_root(sci->sc_root);
2646
2647 down_write(&nilfs->ns_segctor_sem);
2648
2649 del_timer_sync(&sci->sc_timer);
2650 kfree(sci);
2651}
2652
2653/**
2654 * nilfs_attach_log_writer - attach log writer
2655 * @sb: super block instance
2656 * @root: root object of the current filesystem tree
2657 *
2658 * This allocates a log writer object, initializes it, and starts the
2659 * log writer.
2660 *
2661 * Return Value: On success, 0 is returned. On error, one of the following
2662 * negative error code is returned.
2663 *
2664 * %-ENOMEM - Insufficient memory available.
2665 */
2666int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2667{
2668 struct the_nilfs *nilfs = sb->s_fs_info;
2669 int err;
2670
2671 if (nilfs->ns_writer) {
2672 /*
2673 * This happens if the filesystem was remounted
2674 * read/write after nilfs_error degenerated it into a
2675 * read-only mount.
2676 */
2677 nilfs_detach_log_writer(sb);
2678 }
2679
2680 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2681 if (!nilfs->ns_writer)
2682 return -ENOMEM;
2683
2684 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2685 if (err) {
2686 kfree(nilfs->ns_writer);
2687 nilfs->ns_writer = NULL;
2688 }
2689 return err;
2690}
2691
2692/**
2693 * nilfs_detach_log_writer - destroy log writer
2694 * @sb: super block instance
2695 *
2696 * This kills log writer daemon, frees the log writer object, and
2697 * destroys list of dirty files.
2698 */
2699void nilfs_detach_log_writer(struct super_block *sb)
2700{
2701 struct the_nilfs *nilfs = sb->s_fs_info;
2702 LIST_HEAD(garbage_list);
2703
2704 down_write(&nilfs->ns_segctor_sem);
2705 if (nilfs->ns_writer) {
2706 nilfs_segctor_destroy(nilfs->ns_writer);
2707 nilfs->ns_writer = NULL;
2708 }
2709
2710 /* Force to free the list of dirty files */
2711 spin_lock(&nilfs->ns_inode_lock);
2712 if (!list_empty(&nilfs->ns_dirty_files)) {
2713 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2714 nilfs_warning(sb, __func__,
2715 "Hit dirty file after stopped log writer\n");
2716 }
2717 spin_unlock(&nilfs->ns_inode_lock);
2718 up_write(&nilfs->ns_segctor_sem);
2719
2720 nilfs_dispose_list(nilfs, &garbage_list, 1);
2721}