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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * segment.c - NILFS segment constructor.
4 *
5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Ryusuke Konishi.
8 *
9 */
10
11#include <linux/pagemap.h>
12#include <linux/buffer_head.h>
13#include <linux/writeback.h>
14#include <linux/bitops.h>
15#include <linux/bio.h>
16#include <linux/completion.h>
17#include <linux/blkdev.h>
18#include <linux/backing-dev.h>
19#include <linux/freezer.h>
20#include <linux/kthread.h>
21#include <linux/crc32.h>
22#include <linux/pagevec.h>
23#include <linux/slab.h>
24#include <linux/sched/signal.h>
25
26#include "nilfs.h"
27#include "btnode.h"
28#include "page.h"
29#include "segment.h"
30#include "sufile.h"
31#include "cpfile.h"
32#include "ifile.h"
33#include "segbuf.h"
34
35
36/*
37 * Segment constructor
38 */
39#define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
40
41#define SC_MAX_SEGDELTA 64 /*
42 * Upper limit of the number of segments
43 * appended in collection retry loop
44 */
45
46/* Construction mode */
47enum {
48 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
49 SC_LSEG_DSYNC, /*
50 * Flush data blocks of a given file and make
51 * a logical segment without a super root.
52 */
53 SC_FLUSH_FILE, /*
54 * Flush data files, leads to segment writes without
55 * creating a checkpoint.
56 */
57 SC_FLUSH_DAT, /*
58 * Flush DAT file. This also creates segments
59 * without a checkpoint.
60 */
61};
62
63/* Stage numbers of dirty block collection */
64enum {
65 NILFS_ST_INIT = 0,
66 NILFS_ST_GC, /* Collecting dirty blocks for GC */
67 NILFS_ST_FILE,
68 NILFS_ST_IFILE,
69 NILFS_ST_CPFILE,
70 NILFS_ST_SUFILE,
71 NILFS_ST_DAT,
72 NILFS_ST_SR, /* Super root */
73 NILFS_ST_DSYNC, /* Data sync blocks */
74 NILFS_ST_DONE,
75};
76
77#define CREATE_TRACE_POINTS
78#include <trace/events/nilfs2.h>
79
80/*
81 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
82 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
83 * the variable must use them because transition of stage count must involve
84 * trace events (trace_nilfs2_collection_stage_transition).
85 *
86 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
87 * produce tracepoint events. It is provided just for making the intention
88 * clear.
89 */
90static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
91{
92 sci->sc_stage.scnt++;
93 trace_nilfs2_collection_stage_transition(sci);
94}
95
96static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
97{
98 sci->sc_stage.scnt = next_scnt;
99 trace_nilfs2_collection_stage_transition(sci);
100}
101
102static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
103{
104 return sci->sc_stage.scnt;
105}
106
107/* State flags of collection */
108#define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
109#define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
110#define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
111#define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
112
113/* Operations depending on the construction mode and file type */
114struct nilfs_sc_operations {
115 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
116 struct inode *);
117 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
118 struct inode *);
119 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
120 struct inode *);
121 void (*write_data_binfo)(struct nilfs_sc_info *,
122 struct nilfs_segsum_pointer *,
123 union nilfs_binfo *);
124 void (*write_node_binfo)(struct nilfs_sc_info *,
125 struct nilfs_segsum_pointer *,
126 union nilfs_binfo *);
127};
128
129/*
130 * Other definitions
131 */
132static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
133static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
134static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
135static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
136
137#define nilfs_cnt32_gt(a, b) \
138 (typecheck(__u32, a) && typecheck(__u32, b) && \
139 ((__s32)(b) - (__s32)(a) < 0))
140#define nilfs_cnt32_ge(a, b) \
141 (typecheck(__u32, a) && typecheck(__u32, b) && \
142 ((__s32)(a) - (__s32)(b) >= 0))
143#define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
144#define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
145
146static int nilfs_prepare_segment_lock(struct super_block *sb,
147 struct nilfs_transaction_info *ti)
148{
149 struct nilfs_transaction_info *cur_ti = current->journal_info;
150 void *save = NULL;
151
152 if (cur_ti) {
153 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
154 return ++cur_ti->ti_count;
155
156 /*
157 * If journal_info field is occupied by other FS,
158 * it is saved and will be restored on
159 * nilfs_transaction_commit().
160 */
161 nilfs_msg(sb, KERN_WARNING, "journal info from a different FS");
162 save = current->journal_info;
163 }
164 if (!ti) {
165 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
166 if (!ti)
167 return -ENOMEM;
168 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
169 } else {
170 ti->ti_flags = 0;
171 }
172 ti->ti_count = 0;
173 ti->ti_save = save;
174 ti->ti_magic = NILFS_TI_MAGIC;
175 current->journal_info = ti;
176 return 0;
177}
178
179/**
180 * nilfs_transaction_begin - start indivisible file operations.
181 * @sb: super block
182 * @ti: nilfs_transaction_info
183 * @vacancy_check: flags for vacancy rate checks
184 *
185 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
186 * the segment semaphore, to make a segment construction and write tasks
187 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
188 * The region enclosed by these two functions can be nested. To avoid a
189 * deadlock, the semaphore is only acquired or released in the outermost call.
190 *
191 * This function allocates a nilfs_transaction_info struct to keep context
192 * information on it. It is initialized and hooked onto the current task in
193 * the outermost call. If a pre-allocated struct is given to @ti, it is used
194 * instead; otherwise a new struct is assigned from a slab.
195 *
196 * When @vacancy_check flag is set, this function will check the amount of
197 * free space, and will wait for the GC to reclaim disk space if low capacity.
198 *
199 * Return Value: On success, 0 is returned. On error, one of the following
200 * negative error code is returned.
201 *
202 * %-ENOMEM - Insufficient memory available.
203 *
204 * %-ENOSPC - No space left on device
205 */
206int nilfs_transaction_begin(struct super_block *sb,
207 struct nilfs_transaction_info *ti,
208 int vacancy_check)
209{
210 struct the_nilfs *nilfs;
211 int ret = nilfs_prepare_segment_lock(sb, ti);
212 struct nilfs_transaction_info *trace_ti;
213
214 if (unlikely(ret < 0))
215 return ret;
216 if (ret > 0) {
217 trace_ti = current->journal_info;
218
219 trace_nilfs2_transaction_transition(sb, trace_ti,
220 trace_ti->ti_count, trace_ti->ti_flags,
221 TRACE_NILFS2_TRANSACTION_BEGIN);
222 return 0;
223 }
224
225 sb_start_intwrite(sb);
226
227 nilfs = sb->s_fs_info;
228 down_read(&nilfs->ns_segctor_sem);
229 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
230 up_read(&nilfs->ns_segctor_sem);
231 ret = -ENOSPC;
232 goto failed;
233 }
234
235 trace_ti = current->journal_info;
236 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
237 trace_ti->ti_flags,
238 TRACE_NILFS2_TRANSACTION_BEGIN);
239 return 0;
240
241 failed:
242 ti = current->journal_info;
243 current->journal_info = ti->ti_save;
244 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
245 kmem_cache_free(nilfs_transaction_cachep, ti);
246 sb_end_intwrite(sb);
247 return ret;
248}
249
250/**
251 * nilfs_transaction_commit - commit indivisible file operations.
252 * @sb: super block
253 *
254 * nilfs_transaction_commit() releases the read semaphore which is
255 * acquired by nilfs_transaction_begin(). This is only performed
256 * in outermost call of this function. If a commit flag is set,
257 * nilfs_transaction_commit() sets a timer to start the segment
258 * constructor. If a sync flag is set, it starts construction
259 * directly.
260 */
261int nilfs_transaction_commit(struct super_block *sb)
262{
263 struct nilfs_transaction_info *ti = current->journal_info;
264 struct the_nilfs *nilfs = sb->s_fs_info;
265 int err = 0;
266
267 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
268 ti->ti_flags |= NILFS_TI_COMMIT;
269 if (ti->ti_count > 0) {
270 ti->ti_count--;
271 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
272 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
273 return 0;
274 }
275 if (nilfs->ns_writer) {
276 struct nilfs_sc_info *sci = nilfs->ns_writer;
277
278 if (ti->ti_flags & NILFS_TI_COMMIT)
279 nilfs_segctor_start_timer(sci);
280 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
281 nilfs_segctor_do_flush(sci, 0);
282 }
283 up_read(&nilfs->ns_segctor_sem);
284 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
285 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
286
287 current->journal_info = ti->ti_save;
288
289 if (ti->ti_flags & NILFS_TI_SYNC)
290 err = nilfs_construct_segment(sb);
291 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
292 kmem_cache_free(nilfs_transaction_cachep, ti);
293 sb_end_intwrite(sb);
294 return err;
295}
296
297void nilfs_transaction_abort(struct super_block *sb)
298{
299 struct nilfs_transaction_info *ti = current->journal_info;
300 struct the_nilfs *nilfs = sb->s_fs_info;
301
302 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
303 if (ti->ti_count > 0) {
304 ti->ti_count--;
305 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
306 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
307 return;
308 }
309 up_read(&nilfs->ns_segctor_sem);
310
311 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
312 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
313
314 current->journal_info = ti->ti_save;
315 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
316 kmem_cache_free(nilfs_transaction_cachep, ti);
317 sb_end_intwrite(sb);
318}
319
320void nilfs_relax_pressure_in_lock(struct super_block *sb)
321{
322 struct the_nilfs *nilfs = sb->s_fs_info;
323 struct nilfs_sc_info *sci = nilfs->ns_writer;
324
325 if (!sci || !sci->sc_flush_request)
326 return;
327
328 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
329 up_read(&nilfs->ns_segctor_sem);
330
331 down_write(&nilfs->ns_segctor_sem);
332 if (sci->sc_flush_request &&
333 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
334 struct nilfs_transaction_info *ti = current->journal_info;
335
336 ti->ti_flags |= NILFS_TI_WRITER;
337 nilfs_segctor_do_immediate_flush(sci);
338 ti->ti_flags &= ~NILFS_TI_WRITER;
339 }
340 downgrade_write(&nilfs->ns_segctor_sem);
341}
342
343static void nilfs_transaction_lock(struct super_block *sb,
344 struct nilfs_transaction_info *ti,
345 int gcflag)
346{
347 struct nilfs_transaction_info *cur_ti = current->journal_info;
348 struct the_nilfs *nilfs = sb->s_fs_info;
349 struct nilfs_sc_info *sci = nilfs->ns_writer;
350
351 WARN_ON(cur_ti);
352 ti->ti_flags = NILFS_TI_WRITER;
353 ti->ti_count = 0;
354 ti->ti_save = cur_ti;
355 ti->ti_magic = NILFS_TI_MAGIC;
356 current->journal_info = ti;
357
358 for (;;) {
359 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
360 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
361
362 down_write(&nilfs->ns_segctor_sem);
363 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
364 break;
365
366 nilfs_segctor_do_immediate_flush(sci);
367
368 up_write(&nilfs->ns_segctor_sem);
369 cond_resched();
370 }
371 if (gcflag)
372 ti->ti_flags |= NILFS_TI_GC;
373
374 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
375 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
376}
377
378static void nilfs_transaction_unlock(struct super_block *sb)
379{
380 struct nilfs_transaction_info *ti = current->journal_info;
381 struct the_nilfs *nilfs = sb->s_fs_info;
382
383 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
384 BUG_ON(ti->ti_count > 0);
385
386 up_write(&nilfs->ns_segctor_sem);
387 current->journal_info = ti->ti_save;
388
389 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
390 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
391}
392
393static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
394 struct nilfs_segsum_pointer *ssp,
395 unsigned int bytes)
396{
397 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
398 unsigned int blocksize = sci->sc_super->s_blocksize;
399 void *p;
400
401 if (unlikely(ssp->offset + bytes > blocksize)) {
402 ssp->offset = 0;
403 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
404 &segbuf->sb_segsum_buffers));
405 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
406 }
407 p = ssp->bh->b_data + ssp->offset;
408 ssp->offset += bytes;
409 return p;
410}
411
412/**
413 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
414 * @sci: nilfs_sc_info
415 */
416static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
417{
418 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
419 struct buffer_head *sumbh;
420 unsigned int sumbytes;
421 unsigned int flags = 0;
422 int err;
423
424 if (nilfs_doing_gc())
425 flags = NILFS_SS_GC;
426 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
427 if (unlikely(err))
428 return err;
429
430 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
431 sumbytes = segbuf->sb_sum.sumbytes;
432 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
433 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
434 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
435 return 0;
436}
437
438static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
439{
440 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
441 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
442 return -E2BIG; /*
443 * The current segment is filled up
444 * (internal code)
445 */
446 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
447 return nilfs_segctor_reset_segment_buffer(sci);
448}
449
450static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
451{
452 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
453 int err;
454
455 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
456 err = nilfs_segctor_feed_segment(sci);
457 if (err)
458 return err;
459 segbuf = sci->sc_curseg;
460 }
461 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
462 if (likely(!err))
463 segbuf->sb_sum.flags |= NILFS_SS_SR;
464 return err;
465}
466
467/*
468 * Functions for making segment summary and payloads
469 */
470static int nilfs_segctor_segsum_block_required(
471 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
472 unsigned int binfo_size)
473{
474 unsigned int blocksize = sci->sc_super->s_blocksize;
475 /* Size of finfo and binfo is enough small against blocksize */
476
477 return ssp->offset + binfo_size +
478 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
479 blocksize;
480}
481
482static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
483 struct inode *inode)
484{
485 sci->sc_curseg->sb_sum.nfinfo++;
486 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
487 nilfs_segctor_map_segsum_entry(
488 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
489
490 if (NILFS_I(inode)->i_root &&
491 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
492 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
493 /* skip finfo */
494}
495
496static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
497 struct inode *inode)
498{
499 struct nilfs_finfo *finfo;
500 struct nilfs_inode_info *ii;
501 struct nilfs_segment_buffer *segbuf;
502 __u64 cno;
503
504 if (sci->sc_blk_cnt == 0)
505 return;
506
507 ii = NILFS_I(inode);
508
509 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
510 cno = ii->i_cno;
511 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
512 cno = 0;
513 else
514 cno = sci->sc_cno;
515
516 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
517 sizeof(*finfo));
518 finfo->fi_ino = cpu_to_le64(inode->i_ino);
519 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
520 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
521 finfo->fi_cno = cpu_to_le64(cno);
522
523 segbuf = sci->sc_curseg;
524 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
525 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
526 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
527 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
528}
529
530static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
531 struct buffer_head *bh,
532 struct inode *inode,
533 unsigned int binfo_size)
534{
535 struct nilfs_segment_buffer *segbuf;
536 int required, err = 0;
537
538 retry:
539 segbuf = sci->sc_curseg;
540 required = nilfs_segctor_segsum_block_required(
541 sci, &sci->sc_binfo_ptr, binfo_size);
542 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
543 nilfs_segctor_end_finfo(sci, inode);
544 err = nilfs_segctor_feed_segment(sci);
545 if (err)
546 return err;
547 goto retry;
548 }
549 if (unlikely(required)) {
550 err = nilfs_segbuf_extend_segsum(segbuf);
551 if (unlikely(err))
552 goto failed;
553 }
554 if (sci->sc_blk_cnt == 0)
555 nilfs_segctor_begin_finfo(sci, inode);
556
557 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
558 /* Substitution to vblocknr is delayed until update_blocknr() */
559 nilfs_segbuf_add_file_buffer(segbuf, bh);
560 sci->sc_blk_cnt++;
561 failed:
562 return err;
563}
564
565/*
566 * Callback functions that enumerate, mark, and collect dirty blocks
567 */
568static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
569 struct buffer_head *bh, struct inode *inode)
570{
571 int err;
572
573 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
574 if (err < 0)
575 return err;
576
577 err = nilfs_segctor_add_file_block(sci, bh, inode,
578 sizeof(struct nilfs_binfo_v));
579 if (!err)
580 sci->sc_datablk_cnt++;
581 return err;
582}
583
584static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
585 struct buffer_head *bh,
586 struct inode *inode)
587{
588 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
589}
590
591static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
592 struct buffer_head *bh,
593 struct inode *inode)
594{
595 WARN_ON(!buffer_dirty(bh));
596 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
597}
598
599static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
600 struct nilfs_segsum_pointer *ssp,
601 union nilfs_binfo *binfo)
602{
603 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
604 sci, ssp, sizeof(*binfo_v));
605 *binfo_v = binfo->bi_v;
606}
607
608static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
609 struct nilfs_segsum_pointer *ssp,
610 union nilfs_binfo *binfo)
611{
612 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
613 sci, ssp, sizeof(*vblocknr));
614 *vblocknr = binfo->bi_v.bi_vblocknr;
615}
616
617static const struct nilfs_sc_operations nilfs_sc_file_ops = {
618 .collect_data = nilfs_collect_file_data,
619 .collect_node = nilfs_collect_file_node,
620 .collect_bmap = nilfs_collect_file_bmap,
621 .write_data_binfo = nilfs_write_file_data_binfo,
622 .write_node_binfo = nilfs_write_file_node_binfo,
623};
624
625static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
626 struct buffer_head *bh, struct inode *inode)
627{
628 int err;
629
630 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
631 if (err < 0)
632 return err;
633
634 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
635 if (!err)
636 sci->sc_datablk_cnt++;
637 return err;
638}
639
640static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
641 struct buffer_head *bh, struct inode *inode)
642{
643 WARN_ON(!buffer_dirty(bh));
644 return nilfs_segctor_add_file_block(sci, bh, inode,
645 sizeof(struct nilfs_binfo_dat));
646}
647
648static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
649 struct nilfs_segsum_pointer *ssp,
650 union nilfs_binfo *binfo)
651{
652 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
653 sizeof(*blkoff));
654 *blkoff = binfo->bi_dat.bi_blkoff;
655}
656
657static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
658 struct nilfs_segsum_pointer *ssp,
659 union nilfs_binfo *binfo)
660{
661 struct nilfs_binfo_dat *binfo_dat =
662 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
663 *binfo_dat = binfo->bi_dat;
664}
665
666static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
667 .collect_data = nilfs_collect_dat_data,
668 .collect_node = nilfs_collect_file_node,
669 .collect_bmap = nilfs_collect_dat_bmap,
670 .write_data_binfo = nilfs_write_dat_data_binfo,
671 .write_node_binfo = nilfs_write_dat_node_binfo,
672};
673
674static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
675 .collect_data = nilfs_collect_file_data,
676 .collect_node = NULL,
677 .collect_bmap = NULL,
678 .write_data_binfo = nilfs_write_file_data_binfo,
679 .write_node_binfo = NULL,
680};
681
682static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
683 struct list_head *listp,
684 size_t nlimit,
685 loff_t start, loff_t end)
686{
687 struct address_space *mapping = inode->i_mapping;
688 struct pagevec pvec;
689 pgoff_t index = 0, last = ULONG_MAX;
690 size_t ndirties = 0;
691 int i;
692
693 if (unlikely(start != 0 || end != LLONG_MAX)) {
694 /*
695 * A valid range is given for sync-ing data pages. The
696 * range is rounded to per-page; extra dirty buffers
697 * may be included if blocksize < pagesize.
698 */
699 index = start >> PAGE_SHIFT;
700 last = end >> PAGE_SHIFT;
701 }
702 pagevec_init(&pvec);
703 repeat:
704 if (unlikely(index > last) ||
705 !pagevec_lookup_range_tag(&pvec, mapping, &index, last,
706 PAGECACHE_TAG_DIRTY))
707 return ndirties;
708
709 for (i = 0; i < pagevec_count(&pvec); i++) {
710 struct buffer_head *bh, *head;
711 struct page *page = pvec.pages[i];
712
713 lock_page(page);
714 if (!page_has_buffers(page))
715 create_empty_buffers(page, i_blocksize(inode), 0);
716 unlock_page(page);
717
718 bh = head = page_buffers(page);
719 do {
720 if (!buffer_dirty(bh) || buffer_async_write(bh))
721 continue;
722 get_bh(bh);
723 list_add_tail(&bh->b_assoc_buffers, listp);
724 ndirties++;
725 if (unlikely(ndirties >= nlimit)) {
726 pagevec_release(&pvec);
727 cond_resched();
728 return ndirties;
729 }
730 } while (bh = bh->b_this_page, bh != head);
731 }
732 pagevec_release(&pvec);
733 cond_resched();
734 goto repeat;
735}
736
737static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
738 struct list_head *listp)
739{
740 struct nilfs_inode_info *ii = NILFS_I(inode);
741 struct address_space *mapping = &ii->i_btnode_cache;
742 struct pagevec pvec;
743 struct buffer_head *bh, *head;
744 unsigned int i;
745 pgoff_t index = 0;
746
747 pagevec_init(&pvec);
748
749 while (pagevec_lookup_tag(&pvec, mapping, &index,
750 PAGECACHE_TAG_DIRTY)) {
751 for (i = 0; i < pagevec_count(&pvec); i++) {
752 bh = head = page_buffers(pvec.pages[i]);
753 do {
754 if (buffer_dirty(bh) &&
755 !buffer_async_write(bh)) {
756 get_bh(bh);
757 list_add_tail(&bh->b_assoc_buffers,
758 listp);
759 }
760 bh = bh->b_this_page;
761 } while (bh != head);
762 }
763 pagevec_release(&pvec);
764 cond_resched();
765 }
766}
767
768static void nilfs_dispose_list(struct the_nilfs *nilfs,
769 struct list_head *head, int force)
770{
771 struct nilfs_inode_info *ii, *n;
772 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
773 unsigned int nv = 0;
774
775 while (!list_empty(head)) {
776 spin_lock(&nilfs->ns_inode_lock);
777 list_for_each_entry_safe(ii, n, head, i_dirty) {
778 list_del_init(&ii->i_dirty);
779 if (force) {
780 if (unlikely(ii->i_bh)) {
781 brelse(ii->i_bh);
782 ii->i_bh = NULL;
783 }
784 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
785 set_bit(NILFS_I_QUEUED, &ii->i_state);
786 list_add_tail(&ii->i_dirty,
787 &nilfs->ns_dirty_files);
788 continue;
789 }
790 ivec[nv++] = ii;
791 if (nv == SC_N_INODEVEC)
792 break;
793 }
794 spin_unlock(&nilfs->ns_inode_lock);
795
796 for (pii = ivec; nv > 0; pii++, nv--)
797 iput(&(*pii)->vfs_inode);
798 }
799}
800
801static void nilfs_iput_work_func(struct work_struct *work)
802{
803 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
804 sc_iput_work);
805 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
806
807 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
808}
809
810static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
811 struct nilfs_root *root)
812{
813 int ret = 0;
814
815 if (nilfs_mdt_fetch_dirty(root->ifile))
816 ret++;
817 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
818 ret++;
819 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
820 ret++;
821 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
822 ret++;
823 return ret;
824}
825
826static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
827{
828 return list_empty(&sci->sc_dirty_files) &&
829 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
830 sci->sc_nfreesegs == 0 &&
831 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
832}
833
834static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
835{
836 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
837 int ret = 0;
838
839 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
840 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
841
842 spin_lock(&nilfs->ns_inode_lock);
843 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
844 ret++;
845
846 spin_unlock(&nilfs->ns_inode_lock);
847 return ret;
848}
849
850static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
851{
852 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
853
854 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
855 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
856 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
857 nilfs_mdt_clear_dirty(nilfs->ns_dat);
858}
859
860static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
861{
862 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
863 struct buffer_head *bh_cp;
864 struct nilfs_checkpoint *raw_cp;
865 int err;
866
867 /* XXX: this interface will be changed */
868 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
869 &raw_cp, &bh_cp);
870 if (likely(!err)) {
871 /*
872 * The following code is duplicated with cpfile. But, it is
873 * needed to collect the checkpoint even if it was not newly
874 * created.
875 */
876 mark_buffer_dirty(bh_cp);
877 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
878 nilfs_cpfile_put_checkpoint(
879 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
880 } else
881 WARN_ON(err == -EINVAL || err == -ENOENT);
882
883 return err;
884}
885
886static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
887{
888 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
889 struct buffer_head *bh_cp;
890 struct nilfs_checkpoint *raw_cp;
891 int err;
892
893 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
894 &raw_cp, &bh_cp);
895 if (unlikely(err)) {
896 WARN_ON(err == -EINVAL || err == -ENOENT);
897 goto failed_ibh;
898 }
899 raw_cp->cp_snapshot_list.ssl_next = 0;
900 raw_cp->cp_snapshot_list.ssl_prev = 0;
901 raw_cp->cp_inodes_count =
902 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
903 raw_cp->cp_blocks_count =
904 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
905 raw_cp->cp_nblk_inc =
906 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
907 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
908 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
909
910 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
911 nilfs_checkpoint_clear_minor(raw_cp);
912 else
913 nilfs_checkpoint_set_minor(raw_cp);
914
915 nilfs_write_inode_common(sci->sc_root->ifile,
916 &raw_cp->cp_ifile_inode, 1);
917 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
918 return 0;
919
920 failed_ibh:
921 return err;
922}
923
924static void nilfs_fill_in_file_bmap(struct inode *ifile,
925 struct nilfs_inode_info *ii)
926
927{
928 struct buffer_head *ibh;
929 struct nilfs_inode *raw_inode;
930
931 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
932 ibh = ii->i_bh;
933 BUG_ON(!ibh);
934 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
935 ibh);
936 nilfs_bmap_write(ii->i_bmap, raw_inode);
937 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
938 }
939}
940
941static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
942{
943 struct nilfs_inode_info *ii;
944
945 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
946 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
947 set_bit(NILFS_I_COLLECTED, &ii->i_state);
948 }
949}
950
951static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
952 struct the_nilfs *nilfs)
953{
954 struct buffer_head *bh_sr;
955 struct nilfs_super_root *raw_sr;
956 unsigned int isz, srsz;
957
958 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
959 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
960 isz = nilfs->ns_inode_size;
961 srsz = NILFS_SR_BYTES(isz);
962
963 raw_sr->sr_bytes = cpu_to_le16(srsz);
964 raw_sr->sr_nongc_ctime
965 = cpu_to_le64(nilfs_doing_gc() ?
966 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
967 raw_sr->sr_flags = 0;
968
969 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
970 NILFS_SR_DAT_OFFSET(isz), 1);
971 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
972 NILFS_SR_CPFILE_OFFSET(isz), 1);
973 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
974 NILFS_SR_SUFILE_OFFSET(isz), 1);
975 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
976}
977
978static void nilfs_redirty_inodes(struct list_head *head)
979{
980 struct nilfs_inode_info *ii;
981
982 list_for_each_entry(ii, head, i_dirty) {
983 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
984 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
985 }
986}
987
988static void nilfs_drop_collected_inodes(struct list_head *head)
989{
990 struct nilfs_inode_info *ii;
991
992 list_for_each_entry(ii, head, i_dirty) {
993 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
994 continue;
995
996 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
997 set_bit(NILFS_I_UPDATED, &ii->i_state);
998 }
999}
1000
1001static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1002 struct inode *inode,
1003 struct list_head *listp,
1004 int (*collect)(struct nilfs_sc_info *,
1005 struct buffer_head *,
1006 struct inode *))
1007{
1008 struct buffer_head *bh, *n;
1009 int err = 0;
1010
1011 if (collect) {
1012 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1013 list_del_init(&bh->b_assoc_buffers);
1014 err = collect(sci, bh, inode);
1015 brelse(bh);
1016 if (unlikely(err))
1017 goto dispose_buffers;
1018 }
1019 return 0;
1020 }
1021
1022 dispose_buffers:
1023 while (!list_empty(listp)) {
1024 bh = list_first_entry(listp, struct buffer_head,
1025 b_assoc_buffers);
1026 list_del_init(&bh->b_assoc_buffers);
1027 brelse(bh);
1028 }
1029 return err;
1030}
1031
1032static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1033{
1034 /* Remaining number of blocks within segment buffer */
1035 return sci->sc_segbuf_nblocks -
1036 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1037}
1038
1039static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1040 struct inode *inode,
1041 const struct nilfs_sc_operations *sc_ops)
1042{
1043 LIST_HEAD(data_buffers);
1044 LIST_HEAD(node_buffers);
1045 int err;
1046
1047 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1048 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1049
1050 n = nilfs_lookup_dirty_data_buffers(
1051 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1052 if (n > rest) {
1053 err = nilfs_segctor_apply_buffers(
1054 sci, inode, &data_buffers,
1055 sc_ops->collect_data);
1056 BUG_ON(!err); /* always receive -E2BIG or true error */
1057 goto break_or_fail;
1058 }
1059 }
1060 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1061
1062 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1063 err = nilfs_segctor_apply_buffers(
1064 sci, inode, &data_buffers, sc_ops->collect_data);
1065 if (unlikely(err)) {
1066 /* dispose node list */
1067 nilfs_segctor_apply_buffers(
1068 sci, inode, &node_buffers, NULL);
1069 goto break_or_fail;
1070 }
1071 sci->sc_stage.flags |= NILFS_CF_NODE;
1072 }
1073 /* Collect node */
1074 err = nilfs_segctor_apply_buffers(
1075 sci, inode, &node_buffers, sc_ops->collect_node);
1076 if (unlikely(err))
1077 goto break_or_fail;
1078
1079 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1080 err = nilfs_segctor_apply_buffers(
1081 sci, inode, &node_buffers, sc_ops->collect_bmap);
1082 if (unlikely(err))
1083 goto break_or_fail;
1084
1085 nilfs_segctor_end_finfo(sci, inode);
1086 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1087
1088 break_or_fail:
1089 return err;
1090}
1091
1092static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1093 struct inode *inode)
1094{
1095 LIST_HEAD(data_buffers);
1096 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1097 int err;
1098
1099 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1100 sci->sc_dsync_start,
1101 sci->sc_dsync_end);
1102
1103 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1104 nilfs_collect_file_data);
1105 if (!err) {
1106 nilfs_segctor_end_finfo(sci, inode);
1107 BUG_ON(n > rest);
1108 /* always receive -E2BIG or true error if n > rest */
1109 }
1110 return err;
1111}
1112
1113static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1114{
1115 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1116 struct list_head *head;
1117 struct nilfs_inode_info *ii;
1118 size_t ndone;
1119 int err = 0;
1120
1121 switch (nilfs_sc_cstage_get(sci)) {
1122 case NILFS_ST_INIT:
1123 /* Pre-processes */
1124 sci->sc_stage.flags = 0;
1125
1126 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1127 sci->sc_nblk_inc = 0;
1128 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1129 if (mode == SC_LSEG_DSYNC) {
1130 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1131 goto dsync_mode;
1132 }
1133 }
1134
1135 sci->sc_stage.dirty_file_ptr = NULL;
1136 sci->sc_stage.gc_inode_ptr = NULL;
1137 if (mode == SC_FLUSH_DAT) {
1138 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1139 goto dat_stage;
1140 }
1141 nilfs_sc_cstage_inc(sci); /* Fall through */
1142 case NILFS_ST_GC:
1143 if (nilfs_doing_gc()) {
1144 head = &sci->sc_gc_inodes;
1145 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1146 head, i_dirty);
1147 list_for_each_entry_continue(ii, head, i_dirty) {
1148 err = nilfs_segctor_scan_file(
1149 sci, &ii->vfs_inode,
1150 &nilfs_sc_file_ops);
1151 if (unlikely(err)) {
1152 sci->sc_stage.gc_inode_ptr = list_entry(
1153 ii->i_dirty.prev,
1154 struct nilfs_inode_info,
1155 i_dirty);
1156 goto break_or_fail;
1157 }
1158 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1159 }
1160 sci->sc_stage.gc_inode_ptr = NULL;
1161 }
1162 nilfs_sc_cstage_inc(sci); /* Fall through */
1163 case NILFS_ST_FILE:
1164 head = &sci->sc_dirty_files;
1165 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1166 i_dirty);
1167 list_for_each_entry_continue(ii, head, i_dirty) {
1168 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1169
1170 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1171 &nilfs_sc_file_ops);
1172 if (unlikely(err)) {
1173 sci->sc_stage.dirty_file_ptr =
1174 list_entry(ii->i_dirty.prev,
1175 struct nilfs_inode_info,
1176 i_dirty);
1177 goto break_or_fail;
1178 }
1179 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1180 /* XXX: required ? */
1181 }
1182 sci->sc_stage.dirty_file_ptr = NULL;
1183 if (mode == SC_FLUSH_FILE) {
1184 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1185 return 0;
1186 }
1187 nilfs_sc_cstage_inc(sci);
1188 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1189 /* Fall through */
1190 case NILFS_ST_IFILE:
1191 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1192 &nilfs_sc_file_ops);
1193 if (unlikely(err))
1194 break;
1195 nilfs_sc_cstage_inc(sci);
1196 /* Creating a checkpoint */
1197 err = nilfs_segctor_create_checkpoint(sci);
1198 if (unlikely(err))
1199 break;
1200 /* Fall through */
1201 case NILFS_ST_CPFILE:
1202 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1203 &nilfs_sc_file_ops);
1204 if (unlikely(err))
1205 break;
1206 nilfs_sc_cstage_inc(sci); /* Fall through */
1207 case NILFS_ST_SUFILE:
1208 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1209 sci->sc_nfreesegs, &ndone);
1210 if (unlikely(err)) {
1211 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1212 sci->sc_freesegs, ndone,
1213 NULL);
1214 break;
1215 }
1216 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1217
1218 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1219 &nilfs_sc_file_ops);
1220 if (unlikely(err))
1221 break;
1222 nilfs_sc_cstage_inc(sci); /* Fall through */
1223 case NILFS_ST_DAT:
1224 dat_stage:
1225 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1226 &nilfs_sc_dat_ops);
1227 if (unlikely(err))
1228 break;
1229 if (mode == SC_FLUSH_DAT) {
1230 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1231 return 0;
1232 }
1233 nilfs_sc_cstage_inc(sci); /* Fall through */
1234 case NILFS_ST_SR:
1235 if (mode == SC_LSEG_SR) {
1236 /* Appending a super root */
1237 err = nilfs_segctor_add_super_root(sci);
1238 if (unlikely(err))
1239 break;
1240 }
1241 /* End of a logical segment */
1242 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1243 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1244 return 0;
1245 case NILFS_ST_DSYNC:
1246 dsync_mode:
1247 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1248 ii = sci->sc_dsync_inode;
1249 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1250 break;
1251
1252 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1253 if (unlikely(err))
1254 break;
1255 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1256 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1257 return 0;
1258 case NILFS_ST_DONE:
1259 return 0;
1260 default:
1261 BUG();
1262 }
1263
1264 break_or_fail:
1265 return err;
1266}
1267
1268/**
1269 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1270 * @sci: nilfs_sc_info
1271 * @nilfs: nilfs object
1272 */
1273static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1274 struct the_nilfs *nilfs)
1275{
1276 struct nilfs_segment_buffer *segbuf, *prev;
1277 __u64 nextnum;
1278 int err, alloc = 0;
1279
1280 segbuf = nilfs_segbuf_new(sci->sc_super);
1281 if (unlikely(!segbuf))
1282 return -ENOMEM;
1283
1284 if (list_empty(&sci->sc_write_logs)) {
1285 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1286 nilfs->ns_pseg_offset, nilfs);
1287 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1288 nilfs_shift_to_next_segment(nilfs);
1289 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1290 }
1291
1292 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1293 nextnum = nilfs->ns_nextnum;
1294
1295 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1296 /* Start from the head of a new full segment */
1297 alloc++;
1298 } else {
1299 /* Continue logs */
1300 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1301 nilfs_segbuf_map_cont(segbuf, prev);
1302 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1303 nextnum = prev->sb_nextnum;
1304
1305 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1306 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1307 segbuf->sb_sum.seg_seq++;
1308 alloc++;
1309 }
1310 }
1311
1312 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1313 if (err)
1314 goto failed;
1315
1316 if (alloc) {
1317 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1318 if (err)
1319 goto failed;
1320 }
1321 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1322
1323 BUG_ON(!list_empty(&sci->sc_segbufs));
1324 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1325 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1326 return 0;
1327
1328 failed:
1329 nilfs_segbuf_free(segbuf);
1330 return err;
1331}
1332
1333static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1334 struct the_nilfs *nilfs, int nadd)
1335{
1336 struct nilfs_segment_buffer *segbuf, *prev;
1337 struct inode *sufile = nilfs->ns_sufile;
1338 __u64 nextnextnum;
1339 LIST_HEAD(list);
1340 int err, ret, i;
1341
1342 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1343 /*
1344 * Since the segment specified with nextnum might be allocated during
1345 * the previous construction, the buffer including its segusage may
1346 * not be dirty. The following call ensures that the buffer is dirty
1347 * and will pin the buffer on memory until the sufile is written.
1348 */
1349 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1350 if (unlikely(err))
1351 return err;
1352
1353 for (i = 0; i < nadd; i++) {
1354 /* extend segment info */
1355 err = -ENOMEM;
1356 segbuf = nilfs_segbuf_new(sci->sc_super);
1357 if (unlikely(!segbuf))
1358 goto failed;
1359
1360 /* map this buffer to region of segment on-disk */
1361 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1362 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1363
1364 /* allocate the next next full segment */
1365 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1366 if (unlikely(err))
1367 goto failed_segbuf;
1368
1369 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1370 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1371
1372 list_add_tail(&segbuf->sb_list, &list);
1373 prev = segbuf;
1374 }
1375 list_splice_tail(&list, &sci->sc_segbufs);
1376 return 0;
1377
1378 failed_segbuf:
1379 nilfs_segbuf_free(segbuf);
1380 failed:
1381 list_for_each_entry(segbuf, &list, sb_list) {
1382 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1383 WARN_ON(ret); /* never fails */
1384 }
1385 nilfs_destroy_logs(&list);
1386 return err;
1387}
1388
1389static void nilfs_free_incomplete_logs(struct list_head *logs,
1390 struct the_nilfs *nilfs)
1391{
1392 struct nilfs_segment_buffer *segbuf, *prev;
1393 struct inode *sufile = nilfs->ns_sufile;
1394 int ret;
1395
1396 segbuf = NILFS_FIRST_SEGBUF(logs);
1397 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1398 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1399 WARN_ON(ret); /* never fails */
1400 }
1401 if (atomic_read(&segbuf->sb_err)) {
1402 /* Case 1: The first segment failed */
1403 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1404 /*
1405 * Case 1a: Partial segment appended into an existing
1406 * segment
1407 */
1408 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1409 segbuf->sb_fseg_end);
1410 else /* Case 1b: New full segment */
1411 set_nilfs_discontinued(nilfs);
1412 }
1413
1414 prev = segbuf;
1415 list_for_each_entry_continue(segbuf, logs, sb_list) {
1416 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1417 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1418 WARN_ON(ret); /* never fails */
1419 }
1420 if (atomic_read(&segbuf->sb_err) &&
1421 segbuf->sb_segnum != nilfs->ns_nextnum)
1422 /* Case 2: extended segment (!= next) failed */
1423 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1424 prev = segbuf;
1425 }
1426}
1427
1428static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1429 struct inode *sufile)
1430{
1431 struct nilfs_segment_buffer *segbuf;
1432 unsigned long live_blocks;
1433 int ret;
1434
1435 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1436 live_blocks = segbuf->sb_sum.nblocks +
1437 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1438 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1439 live_blocks,
1440 sci->sc_seg_ctime);
1441 WARN_ON(ret); /* always succeed because the segusage is dirty */
1442 }
1443}
1444
1445static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1446{
1447 struct nilfs_segment_buffer *segbuf;
1448 int ret;
1449
1450 segbuf = NILFS_FIRST_SEGBUF(logs);
1451 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1452 segbuf->sb_pseg_start -
1453 segbuf->sb_fseg_start, 0);
1454 WARN_ON(ret); /* always succeed because the segusage is dirty */
1455
1456 list_for_each_entry_continue(segbuf, logs, sb_list) {
1457 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1458 0, 0);
1459 WARN_ON(ret); /* always succeed */
1460 }
1461}
1462
1463static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1464 struct nilfs_segment_buffer *last,
1465 struct inode *sufile)
1466{
1467 struct nilfs_segment_buffer *segbuf = last;
1468 int ret;
1469
1470 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1471 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1472 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1473 WARN_ON(ret);
1474 }
1475 nilfs_truncate_logs(&sci->sc_segbufs, last);
1476}
1477
1478
1479static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1480 struct the_nilfs *nilfs, int mode)
1481{
1482 struct nilfs_cstage prev_stage = sci->sc_stage;
1483 int err, nadd = 1;
1484
1485 /* Collection retry loop */
1486 for (;;) {
1487 sci->sc_nblk_this_inc = 0;
1488 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1489
1490 err = nilfs_segctor_reset_segment_buffer(sci);
1491 if (unlikely(err))
1492 goto failed;
1493
1494 err = nilfs_segctor_collect_blocks(sci, mode);
1495 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1496 if (!err)
1497 break;
1498
1499 if (unlikely(err != -E2BIG))
1500 goto failed;
1501
1502 /* The current segment is filled up */
1503 if (mode != SC_LSEG_SR ||
1504 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1505 break;
1506
1507 nilfs_clear_logs(&sci->sc_segbufs);
1508
1509 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1510 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1511 sci->sc_freesegs,
1512 sci->sc_nfreesegs,
1513 NULL);
1514 WARN_ON(err); /* do not happen */
1515 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1516 }
1517
1518 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1519 if (unlikely(err))
1520 return err;
1521
1522 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1523 sci->sc_stage = prev_stage;
1524 }
1525 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1526 return 0;
1527
1528 failed:
1529 return err;
1530}
1531
1532static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1533 struct buffer_head *new_bh)
1534{
1535 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1536
1537 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1538 /* The caller must release old_bh */
1539}
1540
1541static int
1542nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1543 struct nilfs_segment_buffer *segbuf,
1544 int mode)
1545{
1546 struct inode *inode = NULL;
1547 sector_t blocknr;
1548 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1549 unsigned long nblocks = 0, ndatablk = 0;
1550 const struct nilfs_sc_operations *sc_op = NULL;
1551 struct nilfs_segsum_pointer ssp;
1552 struct nilfs_finfo *finfo = NULL;
1553 union nilfs_binfo binfo;
1554 struct buffer_head *bh, *bh_org;
1555 ino_t ino = 0;
1556 int err = 0;
1557
1558 if (!nfinfo)
1559 goto out;
1560
1561 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1562 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1563 ssp.offset = sizeof(struct nilfs_segment_summary);
1564
1565 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1566 if (bh == segbuf->sb_super_root)
1567 break;
1568 if (!finfo) {
1569 finfo = nilfs_segctor_map_segsum_entry(
1570 sci, &ssp, sizeof(*finfo));
1571 ino = le64_to_cpu(finfo->fi_ino);
1572 nblocks = le32_to_cpu(finfo->fi_nblocks);
1573 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1574
1575 inode = bh->b_page->mapping->host;
1576
1577 if (mode == SC_LSEG_DSYNC)
1578 sc_op = &nilfs_sc_dsync_ops;
1579 else if (ino == NILFS_DAT_INO)
1580 sc_op = &nilfs_sc_dat_ops;
1581 else /* file blocks */
1582 sc_op = &nilfs_sc_file_ops;
1583 }
1584 bh_org = bh;
1585 get_bh(bh_org);
1586 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1587 &binfo);
1588 if (bh != bh_org)
1589 nilfs_list_replace_buffer(bh_org, bh);
1590 brelse(bh_org);
1591 if (unlikely(err))
1592 goto failed_bmap;
1593
1594 if (ndatablk > 0)
1595 sc_op->write_data_binfo(sci, &ssp, &binfo);
1596 else
1597 sc_op->write_node_binfo(sci, &ssp, &binfo);
1598
1599 blocknr++;
1600 if (--nblocks == 0) {
1601 finfo = NULL;
1602 if (--nfinfo == 0)
1603 break;
1604 } else if (ndatablk > 0)
1605 ndatablk--;
1606 }
1607 out:
1608 return 0;
1609
1610 failed_bmap:
1611 return err;
1612}
1613
1614static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1615{
1616 struct nilfs_segment_buffer *segbuf;
1617 int err;
1618
1619 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1620 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1621 if (unlikely(err))
1622 return err;
1623 nilfs_segbuf_fill_in_segsum(segbuf);
1624 }
1625 return 0;
1626}
1627
1628static void nilfs_begin_page_io(struct page *page)
1629{
1630 if (!page || PageWriteback(page))
1631 /*
1632 * For split b-tree node pages, this function may be called
1633 * twice. We ignore the 2nd or later calls by this check.
1634 */
1635 return;
1636
1637 lock_page(page);
1638 clear_page_dirty_for_io(page);
1639 set_page_writeback(page);
1640 unlock_page(page);
1641}
1642
1643static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1644{
1645 struct nilfs_segment_buffer *segbuf;
1646 struct page *bd_page = NULL, *fs_page = NULL;
1647
1648 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1649 struct buffer_head *bh;
1650
1651 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1652 b_assoc_buffers) {
1653 if (bh->b_page != bd_page) {
1654 if (bd_page) {
1655 lock_page(bd_page);
1656 clear_page_dirty_for_io(bd_page);
1657 set_page_writeback(bd_page);
1658 unlock_page(bd_page);
1659 }
1660 bd_page = bh->b_page;
1661 }
1662 }
1663
1664 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1665 b_assoc_buffers) {
1666 set_buffer_async_write(bh);
1667 if (bh == segbuf->sb_super_root) {
1668 if (bh->b_page != bd_page) {
1669 lock_page(bd_page);
1670 clear_page_dirty_for_io(bd_page);
1671 set_page_writeback(bd_page);
1672 unlock_page(bd_page);
1673 bd_page = bh->b_page;
1674 }
1675 break;
1676 }
1677 if (bh->b_page != fs_page) {
1678 nilfs_begin_page_io(fs_page);
1679 fs_page = bh->b_page;
1680 }
1681 }
1682 }
1683 if (bd_page) {
1684 lock_page(bd_page);
1685 clear_page_dirty_for_io(bd_page);
1686 set_page_writeback(bd_page);
1687 unlock_page(bd_page);
1688 }
1689 nilfs_begin_page_io(fs_page);
1690}
1691
1692static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1693 struct the_nilfs *nilfs)
1694{
1695 int ret;
1696
1697 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1698 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1699 return ret;
1700}
1701
1702static void nilfs_end_page_io(struct page *page, int err)
1703{
1704 if (!page)
1705 return;
1706
1707 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1708 /*
1709 * For b-tree node pages, this function may be called twice
1710 * or more because they might be split in a segment.
1711 */
1712 if (PageDirty(page)) {
1713 /*
1714 * For pages holding split b-tree node buffers, dirty
1715 * flag on the buffers may be cleared discretely.
1716 * In that case, the page is once redirtied for
1717 * remaining buffers, and it must be cancelled if
1718 * all the buffers get cleaned later.
1719 */
1720 lock_page(page);
1721 if (nilfs_page_buffers_clean(page))
1722 __nilfs_clear_page_dirty(page);
1723 unlock_page(page);
1724 }
1725 return;
1726 }
1727
1728 if (!err) {
1729 if (!nilfs_page_buffers_clean(page))
1730 __set_page_dirty_nobuffers(page);
1731 ClearPageError(page);
1732 } else {
1733 __set_page_dirty_nobuffers(page);
1734 SetPageError(page);
1735 }
1736
1737 end_page_writeback(page);
1738}
1739
1740static void nilfs_abort_logs(struct list_head *logs, int err)
1741{
1742 struct nilfs_segment_buffer *segbuf;
1743 struct page *bd_page = NULL, *fs_page = NULL;
1744 struct buffer_head *bh;
1745
1746 if (list_empty(logs))
1747 return;
1748
1749 list_for_each_entry(segbuf, logs, sb_list) {
1750 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1751 b_assoc_buffers) {
1752 if (bh->b_page != bd_page) {
1753 if (bd_page)
1754 end_page_writeback(bd_page);
1755 bd_page = bh->b_page;
1756 }
1757 }
1758
1759 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1760 b_assoc_buffers) {
1761 clear_buffer_async_write(bh);
1762 if (bh == segbuf->sb_super_root) {
1763 if (bh->b_page != bd_page) {
1764 end_page_writeback(bd_page);
1765 bd_page = bh->b_page;
1766 }
1767 break;
1768 }
1769 if (bh->b_page != fs_page) {
1770 nilfs_end_page_io(fs_page, err);
1771 fs_page = bh->b_page;
1772 }
1773 }
1774 }
1775 if (bd_page)
1776 end_page_writeback(bd_page);
1777
1778 nilfs_end_page_io(fs_page, err);
1779}
1780
1781static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1782 struct the_nilfs *nilfs, int err)
1783{
1784 LIST_HEAD(logs);
1785 int ret;
1786
1787 list_splice_tail_init(&sci->sc_write_logs, &logs);
1788 ret = nilfs_wait_on_logs(&logs);
1789 nilfs_abort_logs(&logs, ret ? : err);
1790
1791 list_splice_tail_init(&sci->sc_segbufs, &logs);
1792 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1793 nilfs_free_incomplete_logs(&logs, nilfs);
1794
1795 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1796 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1797 sci->sc_freesegs,
1798 sci->sc_nfreesegs,
1799 NULL);
1800 WARN_ON(ret); /* do not happen */
1801 }
1802
1803 nilfs_destroy_logs(&logs);
1804}
1805
1806static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1807 struct nilfs_segment_buffer *segbuf)
1808{
1809 nilfs->ns_segnum = segbuf->sb_segnum;
1810 nilfs->ns_nextnum = segbuf->sb_nextnum;
1811 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1812 + segbuf->sb_sum.nblocks;
1813 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1814 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1815}
1816
1817static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1818{
1819 struct nilfs_segment_buffer *segbuf;
1820 struct page *bd_page = NULL, *fs_page = NULL;
1821 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1822 int update_sr = false;
1823
1824 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1825 struct buffer_head *bh;
1826
1827 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1828 b_assoc_buffers) {
1829 set_buffer_uptodate(bh);
1830 clear_buffer_dirty(bh);
1831 if (bh->b_page != bd_page) {
1832 if (bd_page)
1833 end_page_writeback(bd_page);
1834 bd_page = bh->b_page;
1835 }
1836 }
1837 /*
1838 * We assume that the buffers which belong to the same page
1839 * continue over the buffer list.
1840 * Under this assumption, the last BHs of pages is
1841 * identifiable by the discontinuity of bh->b_page
1842 * (page != fs_page).
1843 *
1844 * For B-tree node blocks, however, this assumption is not
1845 * guaranteed. The cleanup code of B-tree node pages needs
1846 * special care.
1847 */
1848 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1849 b_assoc_buffers) {
1850 const unsigned long set_bits = BIT(BH_Uptodate);
1851 const unsigned long clear_bits =
1852 (BIT(BH_Dirty) | BIT(BH_Async_Write) |
1853 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) |
1854 BIT(BH_NILFS_Redirected));
1855
1856 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1857 if (bh == segbuf->sb_super_root) {
1858 if (bh->b_page != bd_page) {
1859 end_page_writeback(bd_page);
1860 bd_page = bh->b_page;
1861 }
1862 update_sr = true;
1863 break;
1864 }
1865 if (bh->b_page != fs_page) {
1866 nilfs_end_page_io(fs_page, 0);
1867 fs_page = bh->b_page;
1868 }
1869 }
1870
1871 if (!nilfs_segbuf_simplex(segbuf)) {
1872 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1873 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1874 sci->sc_lseg_stime = jiffies;
1875 }
1876 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1877 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1878 }
1879 }
1880 /*
1881 * Since pages may continue over multiple segment buffers,
1882 * end of the last page must be checked outside of the loop.
1883 */
1884 if (bd_page)
1885 end_page_writeback(bd_page);
1886
1887 nilfs_end_page_io(fs_page, 0);
1888
1889 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1890
1891 if (nilfs_doing_gc())
1892 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1893 else
1894 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1895
1896 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1897
1898 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1899 nilfs_set_next_segment(nilfs, segbuf);
1900
1901 if (update_sr) {
1902 nilfs->ns_flushed_device = 0;
1903 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1904 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1905
1906 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1907 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1908 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1909 nilfs_segctor_clear_metadata_dirty(sci);
1910 } else
1911 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1912}
1913
1914static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1915{
1916 int ret;
1917
1918 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1919 if (!ret) {
1920 nilfs_segctor_complete_write(sci);
1921 nilfs_destroy_logs(&sci->sc_write_logs);
1922 }
1923 return ret;
1924}
1925
1926static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1927 struct the_nilfs *nilfs)
1928{
1929 struct nilfs_inode_info *ii, *n;
1930 struct inode *ifile = sci->sc_root->ifile;
1931
1932 spin_lock(&nilfs->ns_inode_lock);
1933 retry:
1934 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1935 if (!ii->i_bh) {
1936 struct buffer_head *ibh;
1937 int err;
1938
1939 spin_unlock(&nilfs->ns_inode_lock);
1940 err = nilfs_ifile_get_inode_block(
1941 ifile, ii->vfs_inode.i_ino, &ibh);
1942 if (unlikely(err)) {
1943 nilfs_msg(sci->sc_super, KERN_WARNING,
1944 "log writer: error %d getting inode block (ino=%lu)",
1945 err, ii->vfs_inode.i_ino);
1946 return err;
1947 }
1948 spin_lock(&nilfs->ns_inode_lock);
1949 if (likely(!ii->i_bh))
1950 ii->i_bh = ibh;
1951 else
1952 brelse(ibh);
1953 goto retry;
1954 }
1955
1956 // Always redirty the buffer to avoid race condition
1957 mark_buffer_dirty(ii->i_bh);
1958 nilfs_mdt_mark_dirty(ifile);
1959
1960 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1961 set_bit(NILFS_I_BUSY, &ii->i_state);
1962 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
1963 }
1964 spin_unlock(&nilfs->ns_inode_lock);
1965
1966 return 0;
1967}
1968
1969static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
1970 struct the_nilfs *nilfs)
1971{
1972 struct nilfs_inode_info *ii, *n;
1973 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
1974 int defer_iput = false;
1975
1976 spin_lock(&nilfs->ns_inode_lock);
1977 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
1978 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
1979 test_bit(NILFS_I_DIRTY, &ii->i_state))
1980 continue;
1981
1982 clear_bit(NILFS_I_BUSY, &ii->i_state);
1983 brelse(ii->i_bh);
1984 ii->i_bh = NULL;
1985 list_del_init(&ii->i_dirty);
1986 if (!ii->vfs_inode.i_nlink || during_mount) {
1987 /*
1988 * Defer calling iput() to avoid deadlocks if
1989 * i_nlink == 0 or mount is not yet finished.
1990 */
1991 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
1992 defer_iput = true;
1993 } else {
1994 spin_unlock(&nilfs->ns_inode_lock);
1995 iput(&ii->vfs_inode);
1996 spin_lock(&nilfs->ns_inode_lock);
1997 }
1998 }
1999 spin_unlock(&nilfs->ns_inode_lock);
2000
2001 if (defer_iput)
2002 schedule_work(&sci->sc_iput_work);
2003}
2004
2005/*
2006 * Main procedure of segment constructor
2007 */
2008static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2009{
2010 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2011 int err;
2012
2013 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2014 sci->sc_cno = nilfs->ns_cno;
2015
2016 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2017 if (unlikely(err))
2018 goto out;
2019
2020 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2021 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2022
2023 if (nilfs_segctor_clean(sci))
2024 goto out;
2025
2026 do {
2027 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2028
2029 err = nilfs_segctor_begin_construction(sci, nilfs);
2030 if (unlikely(err))
2031 goto out;
2032
2033 /* Update time stamp */
2034 sci->sc_seg_ctime = ktime_get_real_seconds();
2035
2036 err = nilfs_segctor_collect(sci, nilfs, mode);
2037 if (unlikely(err))
2038 goto failed;
2039
2040 /* Avoid empty segment */
2041 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2042 nilfs_segbuf_empty(sci->sc_curseg)) {
2043 nilfs_segctor_abort_construction(sci, nilfs, 1);
2044 goto out;
2045 }
2046
2047 err = nilfs_segctor_assign(sci, mode);
2048 if (unlikely(err))
2049 goto failed;
2050
2051 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2052 nilfs_segctor_fill_in_file_bmap(sci);
2053
2054 if (mode == SC_LSEG_SR &&
2055 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2056 err = nilfs_segctor_fill_in_checkpoint(sci);
2057 if (unlikely(err))
2058 goto failed_to_write;
2059
2060 nilfs_segctor_fill_in_super_root(sci, nilfs);
2061 }
2062 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2063
2064 /* Write partial segments */
2065 nilfs_segctor_prepare_write(sci);
2066
2067 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2068 nilfs->ns_crc_seed);
2069
2070 err = nilfs_segctor_write(sci, nilfs);
2071 if (unlikely(err))
2072 goto failed_to_write;
2073
2074 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2075 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2076 /*
2077 * At this point, we avoid double buffering
2078 * for blocksize < pagesize because page dirty
2079 * flag is turned off during write and dirty
2080 * buffers are not properly collected for
2081 * pages crossing over segments.
2082 */
2083 err = nilfs_segctor_wait(sci);
2084 if (err)
2085 goto failed_to_write;
2086 }
2087 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2088
2089 out:
2090 nilfs_segctor_drop_written_files(sci, nilfs);
2091 return err;
2092
2093 failed_to_write:
2094 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2095 nilfs_redirty_inodes(&sci->sc_dirty_files);
2096
2097 failed:
2098 if (nilfs_doing_gc())
2099 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2100 nilfs_segctor_abort_construction(sci, nilfs, err);
2101 goto out;
2102}
2103
2104/**
2105 * nilfs_segctor_start_timer - set timer of background write
2106 * @sci: nilfs_sc_info
2107 *
2108 * If the timer has already been set, it ignores the new request.
2109 * This function MUST be called within a section locking the segment
2110 * semaphore.
2111 */
2112static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2113{
2114 spin_lock(&sci->sc_state_lock);
2115 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2116 sci->sc_timer.expires = jiffies + sci->sc_interval;
2117 add_timer(&sci->sc_timer);
2118 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2119 }
2120 spin_unlock(&sci->sc_state_lock);
2121}
2122
2123static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2124{
2125 spin_lock(&sci->sc_state_lock);
2126 if (!(sci->sc_flush_request & BIT(bn))) {
2127 unsigned long prev_req = sci->sc_flush_request;
2128
2129 sci->sc_flush_request |= BIT(bn);
2130 if (!prev_req)
2131 wake_up(&sci->sc_wait_daemon);
2132 }
2133 spin_unlock(&sci->sc_state_lock);
2134}
2135
2136/**
2137 * nilfs_flush_segment - trigger a segment construction for resource control
2138 * @sb: super block
2139 * @ino: inode number of the file to be flushed out.
2140 */
2141void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2142{
2143 struct the_nilfs *nilfs = sb->s_fs_info;
2144 struct nilfs_sc_info *sci = nilfs->ns_writer;
2145
2146 if (!sci || nilfs_doing_construction())
2147 return;
2148 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2149 /* assign bit 0 to data files */
2150}
2151
2152struct nilfs_segctor_wait_request {
2153 wait_queue_entry_t wq;
2154 __u32 seq;
2155 int err;
2156 atomic_t done;
2157};
2158
2159static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2160{
2161 struct nilfs_segctor_wait_request wait_req;
2162 int err = 0;
2163
2164 spin_lock(&sci->sc_state_lock);
2165 init_wait(&wait_req.wq);
2166 wait_req.err = 0;
2167 atomic_set(&wait_req.done, 0);
2168 wait_req.seq = ++sci->sc_seq_request;
2169 spin_unlock(&sci->sc_state_lock);
2170
2171 init_waitqueue_entry(&wait_req.wq, current);
2172 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2173 set_current_state(TASK_INTERRUPTIBLE);
2174 wake_up(&sci->sc_wait_daemon);
2175
2176 for (;;) {
2177 if (atomic_read(&wait_req.done)) {
2178 err = wait_req.err;
2179 break;
2180 }
2181 if (!signal_pending(current)) {
2182 schedule();
2183 continue;
2184 }
2185 err = -ERESTARTSYS;
2186 break;
2187 }
2188 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2189 return err;
2190}
2191
2192static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2193{
2194 struct nilfs_segctor_wait_request *wrq, *n;
2195 unsigned long flags;
2196
2197 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2198 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
2199 if (!atomic_read(&wrq->done) &&
2200 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2201 wrq->err = err;
2202 atomic_set(&wrq->done, 1);
2203 }
2204 if (atomic_read(&wrq->done)) {
2205 wrq->wq.func(&wrq->wq,
2206 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2207 0, NULL);
2208 }
2209 }
2210 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2211}
2212
2213/**
2214 * nilfs_construct_segment - construct a logical segment
2215 * @sb: super block
2216 *
2217 * Return Value: On success, 0 is retured. On errors, one of the following
2218 * negative error code is returned.
2219 *
2220 * %-EROFS - Read only filesystem.
2221 *
2222 * %-EIO - I/O error
2223 *
2224 * %-ENOSPC - No space left on device (only in a panic state).
2225 *
2226 * %-ERESTARTSYS - Interrupted.
2227 *
2228 * %-ENOMEM - Insufficient memory available.
2229 */
2230int nilfs_construct_segment(struct super_block *sb)
2231{
2232 struct the_nilfs *nilfs = sb->s_fs_info;
2233 struct nilfs_sc_info *sci = nilfs->ns_writer;
2234 struct nilfs_transaction_info *ti;
2235 int err;
2236
2237 if (!sci)
2238 return -EROFS;
2239
2240 /* A call inside transactions causes a deadlock. */
2241 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2242
2243 err = nilfs_segctor_sync(sci);
2244 return err;
2245}
2246
2247/**
2248 * nilfs_construct_dsync_segment - construct a data-only logical segment
2249 * @sb: super block
2250 * @inode: inode whose data blocks should be written out
2251 * @start: start byte offset
2252 * @end: end byte offset (inclusive)
2253 *
2254 * Return Value: On success, 0 is retured. On errors, one of the following
2255 * negative error code is returned.
2256 *
2257 * %-EROFS - Read only filesystem.
2258 *
2259 * %-EIO - I/O error
2260 *
2261 * %-ENOSPC - No space left on device (only in a panic state).
2262 *
2263 * %-ERESTARTSYS - Interrupted.
2264 *
2265 * %-ENOMEM - Insufficient memory available.
2266 */
2267int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2268 loff_t start, loff_t end)
2269{
2270 struct the_nilfs *nilfs = sb->s_fs_info;
2271 struct nilfs_sc_info *sci = nilfs->ns_writer;
2272 struct nilfs_inode_info *ii;
2273 struct nilfs_transaction_info ti;
2274 int err = 0;
2275
2276 if (!sci)
2277 return -EROFS;
2278
2279 nilfs_transaction_lock(sb, &ti, 0);
2280
2281 ii = NILFS_I(inode);
2282 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2283 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2284 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2285 nilfs_discontinued(nilfs)) {
2286 nilfs_transaction_unlock(sb);
2287 err = nilfs_segctor_sync(sci);
2288 return err;
2289 }
2290
2291 spin_lock(&nilfs->ns_inode_lock);
2292 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2293 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2294 spin_unlock(&nilfs->ns_inode_lock);
2295 nilfs_transaction_unlock(sb);
2296 return 0;
2297 }
2298 spin_unlock(&nilfs->ns_inode_lock);
2299 sci->sc_dsync_inode = ii;
2300 sci->sc_dsync_start = start;
2301 sci->sc_dsync_end = end;
2302
2303 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2304 if (!err)
2305 nilfs->ns_flushed_device = 0;
2306
2307 nilfs_transaction_unlock(sb);
2308 return err;
2309}
2310
2311#define FLUSH_FILE_BIT (0x1) /* data file only */
2312#define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2313
2314/**
2315 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2316 * @sci: segment constructor object
2317 */
2318static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2319{
2320 spin_lock(&sci->sc_state_lock);
2321 sci->sc_seq_accepted = sci->sc_seq_request;
2322 spin_unlock(&sci->sc_state_lock);
2323 del_timer_sync(&sci->sc_timer);
2324}
2325
2326/**
2327 * nilfs_segctor_notify - notify the result of request to caller threads
2328 * @sci: segment constructor object
2329 * @mode: mode of log forming
2330 * @err: error code to be notified
2331 */
2332static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2333{
2334 /* Clear requests (even when the construction failed) */
2335 spin_lock(&sci->sc_state_lock);
2336
2337 if (mode == SC_LSEG_SR) {
2338 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2339 sci->sc_seq_done = sci->sc_seq_accepted;
2340 nilfs_segctor_wakeup(sci, err);
2341 sci->sc_flush_request = 0;
2342 } else {
2343 if (mode == SC_FLUSH_FILE)
2344 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2345 else if (mode == SC_FLUSH_DAT)
2346 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2347
2348 /* re-enable timer if checkpoint creation was not done */
2349 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2350 time_before(jiffies, sci->sc_timer.expires))
2351 add_timer(&sci->sc_timer);
2352 }
2353 spin_unlock(&sci->sc_state_lock);
2354}
2355
2356/**
2357 * nilfs_segctor_construct - form logs and write them to disk
2358 * @sci: segment constructor object
2359 * @mode: mode of log forming
2360 */
2361static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2362{
2363 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2364 struct nilfs_super_block **sbp;
2365 int err = 0;
2366
2367 nilfs_segctor_accept(sci);
2368
2369 if (nilfs_discontinued(nilfs))
2370 mode = SC_LSEG_SR;
2371 if (!nilfs_segctor_confirm(sci))
2372 err = nilfs_segctor_do_construct(sci, mode);
2373
2374 if (likely(!err)) {
2375 if (mode != SC_FLUSH_DAT)
2376 atomic_set(&nilfs->ns_ndirtyblks, 0);
2377 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2378 nilfs_discontinued(nilfs)) {
2379 down_write(&nilfs->ns_sem);
2380 err = -EIO;
2381 sbp = nilfs_prepare_super(sci->sc_super,
2382 nilfs_sb_will_flip(nilfs));
2383 if (likely(sbp)) {
2384 nilfs_set_log_cursor(sbp[0], nilfs);
2385 err = nilfs_commit_super(sci->sc_super,
2386 NILFS_SB_COMMIT);
2387 }
2388 up_write(&nilfs->ns_sem);
2389 }
2390 }
2391
2392 nilfs_segctor_notify(sci, mode, err);
2393 return err;
2394}
2395
2396static void nilfs_construction_timeout(struct timer_list *t)
2397{
2398 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2399
2400 wake_up_process(sci->sc_timer_task);
2401}
2402
2403static void
2404nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2405{
2406 struct nilfs_inode_info *ii, *n;
2407
2408 list_for_each_entry_safe(ii, n, head, i_dirty) {
2409 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2410 continue;
2411 list_del_init(&ii->i_dirty);
2412 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2413 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
2414 iput(&ii->vfs_inode);
2415 }
2416}
2417
2418int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2419 void **kbufs)
2420{
2421 struct the_nilfs *nilfs = sb->s_fs_info;
2422 struct nilfs_sc_info *sci = nilfs->ns_writer;
2423 struct nilfs_transaction_info ti;
2424 int err;
2425
2426 if (unlikely(!sci))
2427 return -EROFS;
2428
2429 nilfs_transaction_lock(sb, &ti, 1);
2430
2431 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2432 if (unlikely(err))
2433 goto out_unlock;
2434
2435 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2436 if (unlikely(err)) {
2437 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2438 goto out_unlock;
2439 }
2440
2441 sci->sc_freesegs = kbufs[4];
2442 sci->sc_nfreesegs = argv[4].v_nmembs;
2443 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2444
2445 for (;;) {
2446 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2447 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2448
2449 if (likely(!err))
2450 break;
2451
2452 nilfs_msg(sb, KERN_WARNING, "error %d cleaning segments", err);
2453 set_current_state(TASK_INTERRUPTIBLE);
2454 schedule_timeout(sci->sc_interval);
2455 }
2456 if (nilfs_test_opt(nilfs, DISCARD)) {
2457 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2458 sci->sc_nfreesegs);
2459 if (ret) {
2460 nilfs_msg(sb, KERN_WARNING,
2461 "error %d on discard request, turning discards off for the device",
2462 ret);
2463 nilfs_clear_opt(nilfs, DISCARD);
2464 }
2465 }
2466
2467 out_unlock:
2468 sci->sc_freesegs = NULL;
2469 sci->sc_nfreesegs = 0;
2470 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2471 nilfs_transaction_unlock(sb);
2472 return err;
2473}
2474
2475static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2476{
2477 struct nilfs_transaction_info ti;
2478
2479 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2480 nilfs_segctor_construct(sci, mode);
2481
2482 /*
2483 * Unclosed segment should be retried. We do this using sc_timer.
2484 * Timeout of sc_timer will invoke complete construction which leads
2485 * to close the current logical segment.
2486 */
2487 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2488 nilfs_segctor_start_timer(sci);
2489
2490 nilfs_transaction_unlock(sci->sc_super);
2491}
2492
2493static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2494{
2495 int mode = 0;
2496
2497 spin_lock(&sci->sc_state_lock);
2498 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2499 SC_FLUSH_DAT : SC_FLUSH_FILE;
2500 spin_unlock(&sci->sc_state_lock);
2501
2502 if (mode) {
2503 nilfs_segctor_do_construct(sci, mode);
2504
2505 spin_lock(&sci->sc_state_lock);
2506 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2507 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2508 spin_unlock(&sci->sc_state_lock);
2509 }
2510 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2511}
2512
2513static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2514{
2515 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2516 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2517 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2518 return SC_FLUSH_FILE;
2519 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2520 return SC_FLUSH_DAT;
2521 }
2522 return SC_LSEG_SR;
2523}
2524
2525/**
2526 * nilfs_segctor_thread - main loop of the segment constructor thread.
2527 * @arg: pointer to a struct nilfs_sc_info.
2528 *
2529 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2530 * to execute segment constructions.
2531 */
2532static int nilfs_segctor_thread(void *arg)
2533{
2534 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2535 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2536 int timeout = 0;
2537
2538 sci->sc_timer_task = current;
2539
2540 /* start sync. */
2541 sci->sc_task = current;
2542 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2543 nilfs_msg(sci->sc_super, KERN_INFO,
2544 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
2545 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2546
2547 spin_lock(&sci->sc_state_lock);
2548 loop:
2549 for (;;) {
2550 int mode;
2551
2552 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2553 goto end_thread;
2554
2555 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2556 mode = SC_LSEG_SR;
2557 else if (sci->sc_flush_request)
2558 mode = nilfs_segctor_flush_mode(sci);
2559 else
2560 break;
2561
2562 spin_unlock(&sci->sc_state_lock);
2563 nilfs_segctor_thread_construct(sci, mode);
2564 spin_lock(&sci->sc_state_lock);
2565 timeout = 0;
2566 }
2567
2568
2569 if (freezing(current)) {
2570 spin_unlock(&sci->sc_state_lock);
2571 try_to_freeze();
2572 spin_lock(&sci->sc_state_lock);
2573 } else {
2574 DEFINE_WAIT(wait);
2575 int should_sleep = 1;
2576
2577 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2578 TASK_INTERRUPTIBLE);
2579
2580 if (sci->sc_seq_request != sci->sc_seq_done)
2581 should_sleep = 0;
2582 else if (sci->sc_flush_request)
2583 should_sleep = 0;
2584 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2585 should_sleep = time_before(jiffies,
2586 sci->sc_timer.expires);
2587
2588 if (should_sleep) {
2589 spin_unlock(&sci->sc_state_lock);
2590 schedule();
2591 spin_lock(&sci->sc_state_lock);
2592 }
2593 finish_wait(&sci->sc_wait_daemon, &wait);
2594 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2595 time_after_eq(jiffies, sci->sc_timer.expires));
2596
2597 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2598 set_nilfs_discontinued(nilfs);
2599 }
2600 goto loop;
2601
2602 end_thread:
2603 spin_unlock(&sci->sc_state_lock);
2604
2605 /* end sync. */
2606 sci->sc_task = NULL;
2607 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2608 return 0;
2609}
2610
2611static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2612{
2613 struct task_struct *t;
2614
2615 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2616 if (IS_ERR(t)) {
2617 int err = PTR_ERR(t);
2618
2619 nilfs_msg(sci->sc_super, KERN_ERR,
2620 "error %d creating segctord thread", err);
2621 return err;
2622 }
2623 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2624 return 0;
2625}
2626
2627static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2628 __acquires(&sci->sc_state_lock)
2629 __releases(&sci->sc_state_lock)
2630{
2631 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2632
2633 while (sci->sc_task) {
2634 wake_up(&sci->sc_wait_daemon);
2635 spin_unlock(&sci->sc_state_lock);
2636 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2637 spin_lock(&sci->sc_state_lock);
2638 }
2639}
2640
2641/*
2642 * Setup & clean-up functions
2643 */
2644static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2645 struct nilfs_root *root)
2646{
2647 struct the_nilfs *nilfs = sb->s_fs_info;
2648 struct nilfs_sc_info *sci;
2649
2650 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2651 if (!sci)
2652 return NULL;
2653
2654 sci->sc_super = sb;
2655
2656 nilfs_get_root(root);
2657 sci->sc_root = root;
2658
2659 init_waitqueue_head(&sci->sc_wait_request);
2660 init_waitqueue_head(&sci->sc_wait_daemon);
2661 init_waitqueue_head(&sci->sc_wait_task);
2662 spin_lock_init(&sci->sc_state_lock);
2663 INIT_LIST_HEAD(&sci->sc_dirty_files);
2664 INIT_LIST_HEAD(&sci->sc_segbufs);
2665 INIT_LIST_HEAD(&sci->sc_write_logs);
2666 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2667 INIT_LIST_HEAD(&sci->sc_iput_queue);
2668 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2669 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
2670
2671 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2672 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2673 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2674
2675 if (nilfs->ns_interval)
2676 sci->sc_interval = HZ * nilfs->ns_interval;
2677 if (nilfs->ns_watermark)
2678 sci->sc_watermark = nilfs->ns_watermark;
2679 return sci;
2680}
2681
2682static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2683{
2684 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2685
2686 /*
2687 * The segctord thread was stopped and its timer was removed.
2688 * But some tasks remain.
2689 */
2690 do {
2691 struct nilfs_transaction_info ti;
2692
2693 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2694 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2695 nilfs_transaction_unlock(sci->sc_super);
2696
2697 flush_work(&sci->sc_iput_work);
2698
2699 } while (ret && retrycount-- > 0);
2700}
2701
2702/**
2703 * nilfs_segctor_destroy - destroy the segment constructor.
2704 * @sci: nilfs_sc_info
2705 *
2706 * nilfs_segctor_destroy() kills the segctord thread and frees
2707 * the nilfs_sc_info struct.
2708 * Caller must hold the segment semaphore.
2709 */
2710static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2711{
2712 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2713 int flag;
2714
2715 up_write(&nilfs->ns_segctor_sem);
2716
2717 spin_lock(&sci->sc_state_lock);
2718 nilfs_segctor_kill_thread(sci);
2719 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2720 || sci->sc_seq_request != sci->sc_seq_done);
2721 spin_unlock(&sci->sc_state_lock);
2722
2723 if (flush_work(&sci->sc_iput_work))
2724 flag = true;
2725
2726 if (flag || !nilfs_segctor_confirm(sci))
2727 nilfs_segctor_write_out(sci);
2728
2729 if (!list_empty(&sci->sc_dirty_files)) {
2730 nilfs_msg(sci->sc_super, KERN_WARNING,
2731 "disposed unprocessed dirty file(s) when stopping log writer");
2732 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2733 }
2734
2735 if (!list_empty(&sci->sc_iput_queue)) {
2736 nilfs_msg(sci->sc_super, KERN_WARNING,
2737 "disposed unprocessed inode(s) in iput queue when stopping log writer");
2738 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2739 }
2740
2741 WARN_ON(!list_empty(&sci->sc_segbufs));
2742 WARN_ON(!list_empty(&sci->sc_write_logs));
2743
2744 nilfs_put_root(sci->sc_root);
2745
2746 down_write(&nilfs->ns_segctor_sem);
2747
2748 del_timer_sync(&sci->sc_timer);
2749 kfree(sci);
2750}
2751
2752/**
2753 * nilfs_attach_log_writer - attach log writer
2754 * @sb: super block instance
2755 * @root: root object of the current filesystem tree
2756 *
2757 * This allocates a log writer object, initializes it, and starts the
2758 * log writer.
2759 *
2760 * Return Value: On success, 0 is returned. On error, one of the following
2761 * negative error code is returned.
2762 *
2763 * %-ENOMEM - Insufficient memory available.
2764 */
2765int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2766{
2767 struct the_nilfs *nilfs = sb->s_fs_info;
2768 int err;
2769
2770 if (nilfs->ns_writer) {
2771 /*
2772 * This happens if the filesystem was remounted
2773 * read/write after nilfs_error degenerated it into a
2774 * read-only mount.
2775 */
2776 nilfs_detach_log_writer(sb);
2777 }
2778
2779 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2780 if (!nilfs->ns_writer)
2781 return -ENOMEM;
2782
2783 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2784 if (err) {
2785 kfree(nilfs->ns_writer);
2786 nilfs->ns_writer = NULL;
2787 }
2788 return err;
2789}
2790
2791/**
2792 * nilfs_detach_log_writer - destroy log writer
2793 * @sb: super block instance
2794 *
2795 * This kills log writer daemon, frees the log writer object, and
2796 * destroys list of dirty files.
2797 */
2798void nilfs_detach_log_writer(struct super_block *sb)
2799{
2800 struct the_nilfs *nilfs = sb->s_fs_info;
2801 LIST_HEAD(garbage_list);
2802
2803 down_write(&nilfs->ns_segctor_sem);
2804 if (nilfs->ns_writer) {
2805 nilfs_segctor_destroy(nilfs->ns_writer);
2806 nilfs->ns_writer = NULL;
2807 }
2808
2809 /* Force to free the list of dirty files */
2810 spin_lock(&nilfs->ns_inode_lock);
2811 if (!list_empty(&nilfs->ns_dirty_files)) {
2812 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2813 nilfs_msg(sb, KERN_WARNING,
2814 "disposed unprocessed dirty file(s) when detaching log writer");
2815 }
2816 spin_unlock(&nilfs->ns_inode_lock);
2817 up_write(&nilfs->ns_segctor_sem);
2818
2819 nilfs_dispose_list(nilfs, &garbage_list, 1);
2820}
1/*
2 * segment.c - NILFS segment constructor.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * 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}