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nilfs2: mark minor flag for checkpoint created by internal operation
[deliverable/linux.git] / fs / nilfs2 / segment.c
CommitLineData
9ff05123
RK		 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 "nilfs.h"
36#include "btnode.h"
37#include "page.h"
38#include "segment.h"
39#include "sufile.h"
40#include "cpfile.h"
41#include "ifile.h"
42#include "seglist.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,
9ff05123
RK		 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_HISTORY_MASK (NILFS_CF_IFILE_STARTED)
83
84/* Operations depending on the construction mode and file type */
85struct nilfs_sc_operations {
86 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
87 struct inode *);
88 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
89 struct inode *);
90 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
91 struct inode *);
92 void (*write_data_binfo)(struct nilfs_sc_info *,
93 struct nilfs_segsum_pointer *,
94 union nilfs_binfo *);
95 void (*write_node_binfo)(struct nilfs_sc_info *,
96 struct nilfs_segsum_pointer *,
97 union nilfs_binfo *);
98};
99
100/*
101 * Other definitions
102 */
103static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
104static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
105static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
106static void nilfs_dispose_list(struct nilfs_sb_info *, struct list_head *,
107 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
118/*
119 * Transaction
120 */
121static struct kmem_cache *nilfs_transaction_cachep;
122
123/**
124 * nilfs_init_transaction_cache - create a cache for nilfs_transaction_info
125 *
126 * nilfs_init_transaction_cache() creates a slab cache for the struct
127 * nilfs_transaction_info.
128 *
129 * Return Value: On success, it returns 0. On error, one of the following
130 * negative error code is returned.
131 *
132 * %-ENOMEM - Insufficient memory available.
133 */
134int nilfs_init_transaction_cache(void)
135{
136 nilfs_transaction_cachep =
137 kmem_cache_create("nilfs2_transaction_cache",
138 sizeof(struct nilfs_transaction_info),
139 0, SLAB_RECLAIM_ACCOUNT, NULL);
140 return (nilfs_transaction_cachep == NULL) ? -ENOMEM : 0;
141}
142
143/**
144 * nilfs_detroy_transaction_cache - destroy the cache for transaction info
145 *
146 * nilfs_destroy_transaction_cache() frees the slab cache for the struct
147 * nilfs_transaction_info.
148 */
149void nilfs_destroy_transaction_cache(void)
150{
151 kmem_cache_destroy(nilfs_transaction_cachep);
152}
153
154static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
155{
156 struct nilfs_transaction_info *cur_ti = current->journal_info;
157 void *save = NULL;
158
159 if (cur_ti) {
160 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
161 return ++cur_ti->ti_count;
162 else {
163 /*
164 * If journal_info field is occupied by other FS,
47420c79
RK		 165 * it is saved and will be restored on
166 * nilfs_transaction_commit().
9ff05123
RK		 167 */
168 printk(KERN_WARNING
169 "NILFS warning: journal info from a different "
170 "FS\n");
171 save = current->journal_info;
172 }
173 }
174 if (!ti) {
175 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
176 if (!ti)
177 return -ENOMEM;
178 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
179 } else {
180 ti->ti_flags = 0;
181 }
182 ti->ti_count = 0;
183 ti->ti_save = save;
184 ti->ti_magic = NILFS_TI_MAGIC;
185 current->journal_info = ti;
186 return 0;
187}
188
189/**
190 * nilfs_transaction_begin - start indivisible file operations.
191 * @sb: super block
192 * @ti: nilfs_transaction_info
193 * @vacancy_check: flags for vacancy rate checks
194 *
195 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
196 * the segment semaphore, to make a segment construction and write tasks
47420c79 197 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
9ff05123
RK		 198 * The region enclosed by these two functions can be nested. To avoid a
199 * deadlock, the semaphore is only acquired or released in the outermost call.
200 *
201 * This function allocates a nilfs_transaction_info struct to keep context
202 * information on it. It is initialized and hooked onto the current task in
203 * the outermost call. If a pre-allocated struct is given to @ti, it is used
204 * instead; othewise a new struct is assigned from a slab.
205 *
206 * When @vacancy_check flag is set, this function will check the amount of
207 * free space, and will wait for the GC to reclaim disk space if low capacity.
208 *
209 * Return Value: On success, 0 is returned. On error, one of the following
210 * negative error code is returned.
211 *
212 * %-ENOMEM - Insufficient memory available.
213 *
9ff05123
RK		 214 * %-ENOSPC - No space left on device
215 */
216int nilfs_transaction_begin(struct super_block *sb,
217 struct nilfs_transaction_info *ti,
218 int vacancy_check)
219{
220 struct nilfs_sb_info *sbi;
221 struct the_nilfs *nilfs;
222 int ret = nilfs_prepare_segment_lock(ti);
223
224 if (unlikely(ret < 0))
225 return ret;
226 if (ret > 0)
227 return 0;
228
229 sbi = NILFS_SB(sb);
230 nilfs = sbi->s_nilfs;
231 down_read(&nilfs->ns_segctor_sem);
232 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
233 up_read(&nilfs->ns_segctor_sem);
234 ret = -ENOSPC;
235 goto failed;
236 }
237 return 0;
238
239 failed:
240 ti = current->journal_info;
241 current->journal_info = ti->ti_save;
242 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
243 kmem_cache_free(nilfs_transaction_cachep, ti);
244 return ret;
245}
246
247/**
47420c79 248 * nilfs_transaction_commit - commit indivisible file operations.
9ff05123 249 * @sb: super block
9ff05123 250 *
47420c79
RK		 251 * nilfs_transaction_commit() releases the read semaphore which is
252 * acquired by nilfs_transaction_begin(). This is only performed
253 * in outermost call of this function. If a commit flag is set,
254 * nilfs_transaction_commit() sets a timer to start the segment
255 * constructor. If a sync flag is set, it starts construction
256 * directly.
9ff05123 257 */
47420c79 258int nilfs_transaction_commit(struct super_block *sb)
9ff05123
RK		 259{
260 struct nilfs_transaction_info *ti = current->journal_info;
261 struct nilfs_sb_info *sbi;
262 struct nilfs_sc_info *sci;
263 int err = 0;
264
265 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
47420c79 266 ti->ti_flags |= NILFS_TI_COMMIT;
9ff05123
RK		 267 if (ti->ti_count > 0) {
268 ti->ti_count--;
269 return 0;
270 }
271 sbi = NILFS_SB(sb);
272 sci = NILFS_SC(sbi);
273 if (sci != NULL) {
274 if (ti->ti_flags & NILFS_TI_COMMIT)
275 nilfs_segctor_start_timer(sci);
276 if (atomic_read(&sbi->s_nilfs->ns_ndirtyblks) >
277 sci->sc_watermark)
278 nilfs_segctor_do_flush(sci, 0);
279 }
280 up_read(&sbi->s_nilfs->ns_segctor_sem);
281 current->journal_info = ti->ti_save;
282
283 if (ti->ti_flags & NILFS_TI_SYNC)
284 err = nilfs_construct_segment(sb);
285 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
286 kmem_cache_free(nilfs_transaction_cachep, ti);
287 return err;
288}
289
47420c79
RK		 290void nilfs_transaction_abort(struct super_block *sb)
291{
292 struct nilfs_transaction_info *ti = current->journal_info;
293
294 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
295 if (ti->ti_count > 0) {
296 ti->ti_count--;
297 return;
298 }
299 up_read(&NILFS_SB(sb)->s_nilfs->ns_segctor_sem);
300
301 current->journal_info = ti->ti_save;
302 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
303 kmem_cache_free(nilfs_transaction_cachep, ti);
304}
305
9ff05123
RK		 306void nilfs_relax_pressure_in_lock(struct super_block *sb)
307{
308 struct nilfs_sb_info *sbi = NILFS_SB(sb);
309 struct nilfs_sc_info *sci = NILFS_SC(sbi);
310 struct the_nilfs *nilfs = sbi->s_nilfs;
311
312 if (!sci || !sci->sc_flush_request)
313 return;
314
315 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
316 up_read(&nilfs->ns_segctor_sem);
317
318 down_write(&nilfs->ns_segctor_sem);
319 if (sci->sc_flush_request &&
320 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
321 struct nilfs_transaction_info *ti = current->journal_info;
322
323 ti->ti_flags |= NILFS_TI_WRITER;
324 nilfs_segctor_do_immediate_flush(sci);
325 ti->ti_flags &= ~NILFS_TI_WRITER;
326 }
327 downgrade_write(&nilfs->ns_segctor_sem);
328}
329
330static void nilfs_transaction_lock(struct nilfs_sb_info *sbi,
331 struct nilfs_transaction_info *ti,
332 int gcflag)
333{
334 struct nilfs_transaction_info *cur_ti = current->journal_info;
335
1f5abe7e 336 WARN_ON(cur_ti);
9ff05123
RK		 337 ti->ti_flags = NILFS_TI_WRITER;
338 ti->ti_count = 0;
339 ti->ti_save = cur_ti;
340 ti->ti_magic = NILFS_TI_MAGIC;
341 INIT_LIST_HEAD(&ti->ti_garbage);
342 current->journal_info = ti;
343
344 for (;;) {
345 down_write(&sbi->s_nilfs->ns_segctor_sem);
346 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &NILFS_SC(sbi)->sc_flags))
347 break;
348
349 nilfs_segctor_do_immediate_flush(NILFS_SC(sbi));
350
351 up_write(&sbi->s_nilfs->ns_segctor_sem);
352 yield();
353 }
354 if (gcflag)
355 ti->ti_flags |= NILFS_TI_GC;
356}
357
358static void nilfs_transaction_unlock(struct nilfs_sb_info *sbi)
359{
360 struct nilfs_transaction_info *ti = current->journal_info;
361
362 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
363 BUG_ON(ti->ti_count > 0);
364
365 up_write(&sbi->s_nilfs->ns_segctor_sem);
366 current->journal_info = ti->ti_save;
367 if (!list_empty(&ti->ti_garbage))
368 nilfs_dispose_list(sbi, &ti->ti_garbage, 0);
369}
370
371static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
372 struct nilfs_segsum_pointer *ssp,
373 unsigned bytes)
374{
375 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
376 unsigned blocksize = sci->sc_super->s_blocksize;
377 void *p;
378
379 if (unlikely(ssp->offset + bytes > blocksize)) {
380 ssp->offset = 0;
381 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
382 &segbuf->sb_segsum_buffers));
383 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
384 }
385 p = ssp->bh->b_data + ssp->offset;
386 ssp->offset += bytes;
387 return p;
388}
389
390/**
391 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
392 * @sci: nilfs_sc_info
393 */
394static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
395{
396 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
397 struct buffer_head *sumbh;
398 unsigned sumbytes;
399 unsigned flags = 0;
400 int err;
401
402 if (nilfs_doing_gc())
403 flags = NILFS_SS_GC;
404 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime);
405 if (unlikely(err))
406 return err;
407
408 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
409 sumbytes = segbuf->sb_sum.sumbytes;
410 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
411 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
412 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
413 return 0;
414}
415
416static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
417{
418 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
419 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
420 return -E2BIG; /* The current segment is filled up
421 (internal code) */
422 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
423 return nilfs_segctor_reset_segment_buffer(sci);
424}
425
426static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
427{
428 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
429 int err;
430
431 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
432 err = nilfs_segctor_feed_segment(sci);
433 if (err)
434 return err;
435 segbuf = sci->sc_curseg;
436 }
437 err = nilfs_segbuf_extend_payload(segbuf, &sci->sc_super_root);
438 if (likely(!err))
439 segbuf->sb_sum.flags |= NILFS_SS_SR;
440 return err;
441}
442
443/*
444 * Functions for making segment summary and payloads
445 */
446static int nilfs_segctor_segsum_block_required(
447 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
448 unsigned binfo_size)
449{
450 unsigned blocksize = sci->sc_super->s_blocksize;
451 /* Size of finfo and binfo is enough small against blocksize */
452
453 return ssp->offset + binfo_size +
454 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
455 blocksize;
456}
457
458static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
459 struct inode *inode)
460{
461 sci->sc_curseg->sb_sum.nfinfo++;
462 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
463 nilfs_segctor_map_segsum_entry(
464 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
c96fa464
RK		 465
466 if (inode->i_sb && !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
467 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
9ff05123
RK		 468 /* skip finfo */
469}
470
471static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
472 struct inode *inode)
473{
474 struct nilfs_finfo *finfo;
475 struct nilfs_inode_info *ii;
476 struct nilfs_segment_buffer *segbuf;
477
478 if (sci->sc_blk_cnt == 0)
479 return;
480
481 ii = NILFS_I(inode);
482 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
483 sizeof(*finfo));
484 finfo->fi_ino = cpu_to_le64(inode->i_ino);
485 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
486 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
487 finfo->fi_cno = cpu_to_le64(ii->i_cno);
488
489 segbuf = sci->sc_curseg;
490 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
491 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
492 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
493 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
494}
495
496static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
497 struct buffer_head *bh,
498 struct inode *inode,
499 unsigned binfo_size)
500{
501 struct nilfs_segment_buffer *segbuf;
502 int required, err = 0;
503
504 retry:
505 segbuf = sci->sc_curseg;
506 required = nilfs_segctor_segsum_block_required(
507 sci, &sci->sc_binfo_ptr, binfo_size);
508 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
509 nilfs_segctor_end_finfo(sci, inode);
510 err = nilfs_segctor_feed_segment(sci);
511 if (err)
512 return err;
513 goto retry;
514 }
515 if (unlikely(required)) {
516 err = nilfs_segbuf_extend_segsum(segbuf);
517 if (unlikely(err))
518 goto failed;
519 }
520 if (sci->sc_blk_cnt == 0)
521 nilfs_segctor_begin_finfo(sci, inode);
522
523 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
524 /* Substitution to vblocknr is delayed until update_blocknr() */
525 nilfs_segbuf_add_file_buffer(segbuf, bh);
526 sci->sc_blk_cnt++;
527 failed:
528 return err;
529}
530
531static int nilfs_handle_bmap_error(int err, const char *fname,
532 struct inode *inode, struct super_block *sb)
533{
534 if (err == -EINVAL) {
535 nilfs_error(sb, fname, "broken bmap (inode=%lu)\n",
536 inode->i_ino);
537 err = -EIO;
538 }
539 return err;
540}
541
542/*
543 * Callback functions that enumerate, mark, and collect dirty blocks
544 */
545static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
546 struct buffer_head *bh, struct inode *inode)
547{
548 int err;
549
9ff05123
RK		 550 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
551 if (unlikely(err < 0))
552 return nilfs_handle_bmap_error(err, __func__, inode,
553 sci->sc_super);
554
555 err = nilfs_segctor_add_file_block(sci, bh, inode,
556 sizeof(struct nilfs_binfo_v));
557 if (!err)
558 sci->sc_datablk_cnt++;
559 return err;
560}
561
562static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
563 struct buffer_head *bh,
564 struct inode *inode)
565{
566 int err;
567
9ff05123
RK		 568 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
569 if (unlikely(err < 0))
570 return nilfs_handle_bmap_error(err, __func__, inode,
571 sci->sc_super);
572 return 0;
573}
574
575static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
576 struct buffer_head *bh,
577 struct inode *inode)
578{
1f5abe7e 579 WARN_ON(!buffer_dirty(bh));
9ff05123
RK		 580 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
581}
582
583static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
584 struct nilfs_segsum_pointer *ssp,
585 union nilfs_binfo *binfo)
586{
587 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
588 sci, ssp, sizeof(*binfo_v));
589 *binfo_v = binfo->bi_v;
590}
591
592static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
593 struct nilfs_segsum_pointer *ssp,
594 union nilfs_binfo *binfo)
595{
596 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
597 sci, ssp, sizeof(*vblocknr));
598 *vblocknr = binfo->bi_v.bi_vblocknr;
599}
600
601struct nilfs_sc_operations nilfs_sc_file_ops = {
602 .collect_data = nilfs_collect_file_data,
603 .collect_node = nilfs_collect_file_node,
604 .collect_bmap = nilfs_collect_file_bmap,
605 .write_data_binfo = nilfs_write_file_data_binfo,
606 .write_node_binfo = nilfs_write_file_node_binfo,
607};
608
609static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
610 struct buffer_head *bh, struct inode *inode)
611{
612 int err;
613
614 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
615 if (unlikely(err < 0))
616 return nilfs_handle_bmap_error(err, __func__, inode,
617 sci->sc_super);
618
619 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
620 if (!err)
621 sci->sc_datablk_cnt++;
622 return err;
623}
624
625static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
626 struct buffer_head *bh, struct inode *inode)
627{
1f5abe7e 628 WARN_ON(!buffer_dirty(bh));
9ff05123
RK		 629 return nilfs_segctor_add_file_block(sci, bh, inode,
630 sizeof(struct nilfs_binfo_dat));
631}
632
633static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
634 struct nilfs_segsum_pointer *ssp,
635 union nilfs_binfo *binfo)
636{
637 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
638 sizeof(*blkoff));
639 *blkoff = binfo->bi_dat.bi_blkoff;
640}
641
642static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
643 struct nilfs_segsum_pointer *ssp,
644 union nilfs_binfo *binfo)
645{
646 struct nilfs_binfo_dat *binfo_dat =
647 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
648 *binfo_dat = binfo->bi_dat;
649}
650
651struct nilfs_sc_operations nilfs_sc_dat_ops = {
652 .collect_data = nilfs_collect_dat_data,
653 .collect_node = nilfs_collect_file_node,
654 .collect_bmap = nilfs_collect_dat_bmap,
655 .write_data_binfo = nilfs_write_dat_data_binfo,
656 .write_node_binfo = nilfs_write_dat_node_binfo,
657};
658
659struct nilfs_sc_operations nilfs_sc_dsync_ops = {
660 .collect_data = nilfs_collect_file_data,
661 .collect_node = NULL,
662 .collect_bmap = NULL,
663 .write_data_binfo = nilfs_write_file_data_binfo,
664 .write_node_binfo = NULL,
665};
666
f30bf3e4
RK		 667static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
668 struct list_head *listp,
669 size_t nlimit,
670 loff_t start, loff_t end)
9ff05123 671{
9ff05123
RK		 672 struct address_space *mapping = inode->i_mapping;
673 struct pagevec pvec;
f30bf3e4
RK		 674 pgoff_t index = 0, last = ULONG_MAX;
675 size_t ndirties = 0;
676 int i;
9ff05123 677
f30bf3e4
RK		 678 if (unlikely(start != 0 || end != LLONG_MAX)) {
679 /*
680 * A valid range is given for sync-ing data pages. The
681 * range is rounded to per-page; extra dirty buffers
682 * may be included if blocksize < pagesize.
683 */
684 index = start >> PAGE_SHIFT;
685 last = end >> PAGE_SHIFT;
686 }
9ff05123
RK		 687 pagevec_init(&pvec, 0);
688 repeat:
f30bf3e4
RK		 689 if (unlikely(index > last) ||
690 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
691 min_t(pgoff_t, last - index,
692 PAGEVEC_SIZE - 1) + 1))
693 return ndirties;
9ff05123
RK		 694
695 for (i = 0; i < pagevec_count(&pvec); i++) {
696 struct buffer_head *bh, *head;
697 struct page *page = pvec.pages[i];
698
f30bf3e4
RK		 699 if (unlikely(page->index > last))
700 break;
701
9ff05123
RK		 702 if (mapping->host) {
703 lock_page(page);
704 if (!page_has_buffers(page))
705 create_empty_buffers(page,
706 1 << inode->i_blkbits, 0);
707 unlock_page(page);
708 }
709
710 bh = head = page_buffers(page);
711 do {
f30bf3e4
RK		 712 if (!buffer_dirty(bh))
713 continue;
714 get_bh(bh);
715 list_add_tail(&bh->b_assoc_buffers, listp);
716 ndirties++;
717 if (unlikely(ndirties >= nlimit)) {
718 pagevec_release(&pvec);
719 cond_resched();
720 return ndirties;
9ff05123 721 }
f30bf3e4 722 } while (bh = bh->b_this_page, bh != head);
9ff05123
RK		 723 }
724 pagevec_release(&pvec);
725 cond_resched();
f30bf3e4 726 goto repeat;
9ff05123
RK		 727}
728
729static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
730 struct list_head *listp)
731{
732 struct nilfs_inode_info *ii = NILFS_I(inode);
733 struct address_space *mapping = &ii->i_btnode_cache;
734 struct pagevec pvec;
735 struct buffer_head *bh, *head;
736 unsigned int i;
737 pgoff_t index = 0;
738
739 pagevec_init(&pvec, 0);
740
741 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
742 PAGEVEC_SIZE)) {
743 for (i = 0; i < pagevec_count(&pvec); i++) {
744 bh = head = page_buffers(pvec.pages[i]);
745 do {
746 if (buffer_dirty(bh)) {
747 get_bh(bh);
748 list_add_tail(&bh->b_assoc_buffers,
749 listp);
750 }
751 bh = bh->b_this_page;
752 } while (bh != head);
753 }
754 pagevec_release(&pvec);
755 cond_resched();
756 }
757}
758
759static void nilfs_dispose_list(struct nilfs_sb_info *sbi,
760 struct list_head *head, int force)
761{
762 struct nilfs_inode_info *ii, *n;
763 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
764 unsigned nv = 0;
765
766 while (!list_empty(head)) {
767 spin_lock(&sbi->s_inode_lock);
768 list_for_each_entry_safe(ii, n, head, i_dirty) {
769 list_del_init(&ii->i_dirty);
770 if (force) {
771 if (unlikely(ii->i_bh)) {
772 brelse(ii->i_bh);
773 ii->i_bh = NULL;
774 }
775 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
776 set_bit(NILFS_I_QUEUED, &ii->i_state);
777 list_add_tail(&ii->i_dirty,
778 &sbi->s_dirty_files);
779 continue;
780 }
781 ivec[nv++] = ii;
782 if (nv == SC_N_INODEVEC)
783 break;
784 }
785 spin_unlock(&sbi->s_inode_lock);
786
787 for (pii = ivec; nv > 0; pii++, nv--)
788 iput(&(*pii)->vfs_inode);
789 }
790}
791
792static int nilfs_test_metadata_dirty(struct nilfs_sb_info *sbi)
793{
794 struct the_nilfs *nilfs = sbi->s_nilfs;
795 int ret = 0;
796
797 if (nilfs_mdt_fetch_dirty(sbi->s_ifile))
798 ret++;
799 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
800 ret++;
801 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
802 ret++;
803 if (ret || nilfs_doing_gc())
804 if (nilfs_mdt_fetch_dirty(nilfs_dat_inode(nilfs)))
805 ret++;
806 return ret;
807}
808
809static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
810{
811 return list_empty(&sci->sc_dirty_files) &&
812 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
813 list_empty(&sci->sc_cleaning_segments) &&
814 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
815}
816
817static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
818{
819 struct nilfs_sb_info *sbi = sci->sc_sbi;
820 int ret = 0;
821
822 if (nilfs_test_metadata_dirty(sbi))
823 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
824
825 spin_lock(&sbi->s_inode_lock);
826 if (list_empty(&sbi->s_dirty_files) && nilfs_segctor_clean(sci))
827 ret++;
828
829 spin_unlock(&sbi->s_inode_lock);
830 return ret;
831}
832
833static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
834{
835 struct nilfs_sb_info *sbi = sci->sc_sbi;
836 struct the_nilfs *nilfs = sbi->s_nilfs;
837
838 nilfs_mdt_clear_dirty(sbi->s_ifile);
839 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
840 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
841 nilfs_mdt_clear_dirty(nilfs_dat_inode(nilfs));
842}
843
844static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
845{
846 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
847 struct buffer_head *bh_cp;
848 struct nilfs_checkpoint *raw_cp;
849 int err;
850
851 /* XXX: this interface will be changed */
852 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
853 &raw_cp, &bh_cp);
854 if (likely(!err)) {
855 /* The following code is duplicated with cpfile. But, it is
856 needed to collect the checkpoint even if it was not newly
857 created */
858 nilfs_mdt_mark_buffer_dirty(bh_cp);
859 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
860 nilfs_cpfile_put_checkpoint(
861 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
1f5abe7e
RK		 862 } else
863 WARN_ON(err == -EINVAL || err == -ENOENT);
864
9ff05123
RK		 865 return err;
866}
867
868static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
869{
870 struct nilfs_sb_info *sbi = sci->sc_sbi;
871 struct the_nilfs *nilfs = sbi->s_nilfs;
872 struct buffer_head *bh_cp;
873 struct nilfs_checkpoint *raw_cp;
874 int err;
875
876 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
877 &raw_cp, &bh_cp);
878 if (unlikely(err)) {
1f5abe7e 879 WARN_ON(err == -EINVAL || err == -ENOENT);
9ff05123
RK		 880 goto failed_ibh;
881 }
882 raw_cp->cp_snapshot_list.ssl_next = 0;
883 raw_cp->cp_snapshot_list.ssl_prev = 0;
884 raw_cp->cp_inodes_count =
885 cpu_to_le64(atomic_read(&sbi->s_inodes_count));
886 raw_cp->cp_blocks_count =
887 cpu_to_le64(atomic_read(&sbi->s_blocks_count));
888 raw_cp->cp_nblk_inc =
889 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
890 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
891 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
458c5b08 892
c96fa464
RK		 893 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
894 nilfs_checkpoint_clear_minor(raw_cp);
895 else
896 nilfs_checkpoint_set_minor(raw_cp);
897
9ff05123
RK		 898 nilfs_write_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode, 1);
899 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
900 return 0;
901
902 failed_ibh:
903 return err;
904}
905
906static void nilfs_fill_in_file_bmap(struct inode *ifile,
907 struct nilfs_inode_info *ii)
908
909{
910 struct buffer_head *ibh;
911 struct nilfs_inode *raw_inode;
912
913 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
914 ibh = ii->i_bh;
915 BUG_ON(!ibh);
916 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
917 ibh);
918 nilfs_bmap_write(ii->i_bmap, raw_inode);
919 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
920 }
921}
922
923static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci,
924 struct inode *ifile)
925{
926 struct nilfs_inode_info *ii;
927
928 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
929 nilfs_fill_in_file_bmap(ifile, ii);
930 set_bit(NILFS_I_COLLECTED, &ii->i_state);
931 }
9ff05123
RK		 932}
933
934/*
935 * CRC calculation routines
936 */
937static void nilfs_fill_in_super_root_crc(struct buffer_head *bh_sr, u32 seed)
938{
939 struct nilfs_super_root *raw_sr =
940 (struct nilfs_super_root *)bh_sr->b_data;
941 u32 crc;
942
9ff05123
RK		 943 crc = crc32_le(seed,
944 (unsigned char *)raw_sr + sizeof(raw_sr->sr_sum),
945 NILFS_SR_BYTES - sizeof(raw_sr->sr_sum));
946 raw_sr->sr_sum = cpu_to_le32(crc);
947}
948
949static void nilfs_segctor_fill_in_checksums(struct nilfs_sc_info *sci,
950 u32 seed)
951{
952 struct nilfs_segment_buffer *segbuf;
953
954 if (sci->sc_super_root)
955 nilfs_fill_in_super_root_crc(sci->sc_super_root, seed);
956
957 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
958 nilfs_segbuf_fill_in_segsum_crc(segbuf, seed);
959 nilfs_segbuf_fill_in_data_crc(segbuf, seed);
960 }
961}
962
963static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
964 struct the_nilfs *nilfs)
965{
966 struct buffer_head *bh_sr = sci->sc_super_root;
967 struct nilfs_super_root *raw_sr =
968 (struct nilfs_super_root *)bh_sr->b_data;
969 unsigned isz = nilfs->ns_inode_size;
970
971 raw_sr->sr_bytes = cpu_to_le16(NILFS_SR_BYTES);
972 raw_sr->sr_nongc_ctime
973 = cpu_to_le64(nilfs_doing_gc() ?
974 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
975 raw_sr->sr_flags = 0;
976
977 nilfs_mdt_write_inode_direct(
978 nilfs_dat_inode(nilfs), bh_sr, NILFS_SR_DAT_OFFSET(isz));
979 nilfs_mdt_write_inode_direct(
980 nilfs->ns_cpfile, bh_sr, NILFS_SR_CPFILE_OFFSET(isz));
981 nilfs_mdt_write_inode_direct(
982 nilfs->ns_sufile, bh_sr, NILFS_SR_SUFILE_OFFSET(isz));
983}
984
985static void nilfs_redirty_inodes(struct list_head *head)
986{
987 struct nilfs_inode_info *ii;
988
989 list_for_each_entry(ii, head, i_dirty) {
990 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
991 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
992 }
993}
994
995static void nilfs_drop_collected_inodes(struct list_head *head)
996{
997 struct nilfs_inode_info *ii;
998
999 list_for_each_entry(ii, head, i_dirty) {
1000 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
1001 continue;
1002
1003 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
1004 set_bit(NILFS_I_UPDATED, &ii->i_state);
1005 }
1006}
1007
1008static void nilfs_segctor_cancel_free_segments(struct nilfs_sc_info *sci,
1009 struct inode *sufile)
1010
1011{
1012 struct list_head *head = &sci->sc_cleaning_segments;
1013 struct nilfs_segment_entry *ent;
1014 int err;
1015
1016 list_for_each_entry(ent, head, list) {
1017 if (!(ent->flags & NILFS_SLH_FREED))
1018 break;
1019 err = nilfs_sufile_cancel_free(sufile, ent->segnum);
1f5abe7e 1020 WARN_ON(err); /* do not happen */
9ff05123
RK		 1021 ent->flags &= ~NILFS_SLH_FREED;
1022 }
1023}
1024
1025static int nilfs_segctor_prepare_free_segments(struct nilfs_sc_info *sci,
1026 struct inode *sufile)
1027{
1028 struct list_head *head = &sci->sc_cleaning_segments;
1029 struct nilfs_segment_entry *ent;
1030 int err;
1031
1032 list_for_each_entry(ent, head, list) {
1033 err = nilfs_sufile_free(sufile, ent->segnum);
1034 if (unlikely(err))
1035 return err;
1036 ent->flags |= NILFS_SLH_FREED;
1037 }
1038 return 0;
1039}
1040
1041static void nilfs_segctor_commit_free_segments(struct nilfs_sc_info *sci)
1042{
1043 nilfs_dispose_segment_list(&sci->sc_cleaning_segments);
1044}
1045
1046static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1047 struct inode *inode,
1048 struct list_head *listp,
1049 int (*collect)(struct nilfs_sc_info *,
1050 struct buffer_head *,
1051 struct inode *))
1052{
1053 struct buffer_head *bh, *n;
1054 int err = 0;
1055
1056 if (collect) {
1057 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1058 list_del_init(&bh->b_assoc_buffers);
1059 err = collect(sci, bh, inode);
1060 brelse(bh);
1061 if (unlikely(err))
1062 goto dispose_buffers;
1063 }
1064 return 0;
1065 }
1066
1067 dispose_buffers:
1068 while (!list_empty(listp)) {
1069 bh = list_entry(listp->next, struct buffer_head,
1070 b_assoc_buffers);
1071 list_del_init(&bh->b_assoc_buffers);
1072 brelse(bh);
1073 }
1074 return err;
1075}
1076
f30bf3e4
RK		 1077static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1078{
1079 /* Remaining number of blocks within segment buffer */
1080 return sci->sc_segbuf_nblocks -
1081 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1082}
1083
9ff05123
RK		 1084static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1085 struct inode *inode,
1086 struct nilfs_sc_operations *sc_ops)
1087{
1088 LIST_HEAD(data_buffers);
1089 LIST_HEAD(node_buffers);
f30bf3e4 1090 int err;
9ff05123
RK		 1091
1092 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
f30bf3e4
RK		 1093 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1094
1095 n = nilfs_lookup_dirty_data_buffers(
1096 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1097 if (n > rest) {
1098 err = nilfs_segctor_apply_buffers(
9ff05123 1099 sci, inode, &data_buffers,
f30bf3e4
RK		 1100 sc_ops->collect_data);
1101 BUG_ON(!err); /* always receive -E2BIG or true error */
9ff05123
RK		 1102 goto break_or_fail;
1103 }
1104 }
1105 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1106
1107 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1108 err = nilfs_segctor_apply_buffers(
1109 sci, inode, &data_buffers, sc_ops->collect_data);
1110 if (unlikely(err)) {
1111 /* dispose node list */
1112 nilfs_segctor_apply_buffers(
1113 sci, inode, &node_buffers, NULL);
1114 goto break_or_fail;
1115 }
1116 sci->sc_stage.flags |= NILFS_CF_NODE;
1117 }
1118 /* Collect node */
1119 err = nilfs_segctor_apply_buffers(
1120 sci, inode, &node_buffers, sc_ops->collect_node);
1121 if (unlikely(err))
1122 goto break_or_fail;
1123
1124 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1125 err = nilfs_segctor_apply_buffers(
1126 sci, inode, &node_buffers, sc_ops->collect_bmap);
1127 if (unlikely(err))
1128 goto break_or_fail;
1129
1130 nilfs_segctor_end_finfo(sci, inode);
1131 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1132
1133 break_or_fail:
1134 return err;
1135}
1136
1137static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1138 struct inode *inode)
1139{
1140 LIST_HEAD(data_buffers);
f30bf3e4
RK		 1141 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1142 int err;
9ff05123 1143
f30bf3e4
RK		 1144 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1145 sci->sc_dsync_start,
1146 sci->sc_dsync_end);
1147
1148 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1149 nilfs_collect_file_data);
1150 if (!err) {
9ff05123 1151 nilfs_segctor_end_finfo(sci, inode);
f30bf3e4
RK		 1152 BUG_ON(n > rest);
1153 /* always receive -E2BIG or true error if n > rest */
1154 }
9ff05123
RK		 1155 return err;
1156}
1157
1158static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1159{
1160 struct nilfs_sb_info *sbi = sci->sc_sbi;
1161 struct the_nilfs *nilfs = sbi->s_nilfs;
1162 struct list_head *head;
1163 struct nilfs_inode_info *ii;
1164 int err = 0;
1165
1166 switch (sci->sc_stage.scnt) {
1167 case NILFS_ST_INIT:
1168 /* Pre-processes */
1169 sci->sc_stage.flags = 0;
1170
1171 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1172 sci->sc_nblk_inc = 0;
1173 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1174 if (mode == SC_LSEG_DSYNC) {
1175 sci->sc_stage.scnt = NILFS_ST_DSYNC;
1176 goto dsync_mode;
1177 }
1178 }
1179
1180 sci->sc_stage.dirty_file_ptr = NULL;
1181 sci->sc_stage.gc_inode_ptr = NULL;
1182 if (mode == SC_FLUSH_DAT) {
1183 sci->sc_stage.scnt = NILFS_ST_DAT;
1184 goto dat_stage;
1185 }
1186 sci->sc_stage.scnt++; /* Fall through */
1187 case NILFS_ST_GC:
1188 if (nilfs_doing_gc()) {
1189 head = &sci->sc_gc_inodes;
1190 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1191 head, i_dirty);
1192 list_for_each_entry_continue(ii, head, i_dirty) {
1193 err = nilfs_segctor_scan_file(
1194 sci, &ii->vfs_inode,
1195 &nilfs_sc_file_ops);
1196 if (unlikely(err)) {
1197 sci->sc_stage.gc_inode_ptr = list_entry(
1198 ii->i_dirty.prev,
1199 struct nilfs_inode_info,
1200 i_dirty);
1201 goto break_or_fail;
1202 }
1203 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1204 }
1205 sci->sc_stage.gc_inode_ptr = NULL;
1206 }
1207 sci->sc_stage.scnt++; /* Fall through */
1208 case NILFS_ST_FILE:
1209 head = &sci->sc_dirty_files;
1210 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1211 i_dirty);
1212 list_for_each_entry_continue(ii, head, i_dirty) {
1213 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1214
1215 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1216 &nilfs_sc_file_ops);
1217 if (unlikely(err)) {
1218 sci->sc_stage.dirty_file_ptr =
1219 list_entry(ii->i_dirty.prev,
1220 struct nilfs_inode_info,
1221 i_dirty);
1222 goto break_or_fail;
1223 }
1224 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1225 /* XXX: required ? */
1226 }
1227 sci->sc_stage.dirty_file_ptr = NULL;
1228 if (mode == SC_FLUSH_FILE) {
1229 sci->sc_stage.scnt = NILFS_ST_DONE;
1230 return 0;
1231 }
9ff05123
RK		 1232 sci->sc_stage.scnt++;
1233 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1234 /* Fall through */
1235 case NILFS_ST_IFILE:
1236 err = nilfs_segctor_scan_file(sci, sbi->s_ifile,
1237 &nilfs_sc_file_ops);
1238 if (unlikely(err))
1239 break;
1240 sci->sc_stage.scnt++;
1241 /* Creating a checkpoint */
1242 err = nilfs_segctor_create_checkpoint(sci);
1243 if (unlikely(err))
1244 break;
1245 /* Fall through */
1246 case NILFS_ST_CPFILE:
1247 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1248 &nilfs_sc_file_ops);
1249 if (unlikely(err))
1250 break;
1251 sci->sc_stage.scnt++; /* Fall through */
1252 case NILFS_ST_SUFILE:
1253 err = nilfs_segctor_prepare_free_segments(sci,
1254 nilfs->ns_sufile);
1255 if (unlikely(err))
1256 break;
1257 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1258 &nilfs_sc_file_ops);
1259 if (unlikely(err))
1260 break;
1261 sci->sc_stage.scnt++; /* Fall through */
1262 case NILFS_ST_DAT:
1263 dat_stage:
1264 err = nilfs_segctor_scan_file(sci, nilfs_dat_inode(nilfs),
1265 &nilfs_sc_dat_ops);
1266 if (unlikely(err))
1267 break;
1268 if (mode == SC_FLUSH_DAT) {
1269 sci->sc_stage.scnt = NILFS_ST_DONE;
1270 return 0;
1271 }
1272 sci->sc_stage.scnt++; /* Fall through */
1273 case NILFS_ST_SR:
1274 if (mode == SC_LSEG_SR) {
1275 /* Appending a super root */
1276 err = nilfs_segctor_add_super_root(sci);
1277 if (unlikely(err))
1278 break;
1279 }
1280 /* End of a logical segment */
1281 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1282 sci->sc_stage.scnt = NILFS_ST_DONE;
1283 return 0;
1284 case NILFS_ST_DSYNC:
1285 dsync_mode:
1286 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
f30bf3e4 1287 ii = sci->sc_dsync_inode;
9ff05123
RK		 1288 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1289 break;
1290
1291 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1292 if (unlikely(err))
1293 break;
9ff05123
RK		 1294 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1295 sci->sc_stage.scnt = NILFS_ST_DONE;
1296 return 0;
1297 case NILFS_ST_DONE:
1298 return 0;
1299 default:
1300 BUG();
1301 }
1302
1303 break_or_fail:
1304 return err;
1305}
1306
1307static int nilfs_segctor_terminate_segment(struct nilfs_sc_info *sci,
1308 struct nilfs_segment_buffer *segbuf,
1309 struct inode *sufile)
1310{
1311 struct nilfs_segment_entry *ent = segbuf->sb_segent;
1312 int err;
1313
1314 err = nilfs_open_segment_entry(ent, sufile);
1315 if (unlikely(err))
1316 return err;
1317 nilfs_mdt_mark_buffer_dirty(ent->bh_su);
1318 nilfs_mdt_mark_dirty(sufile);
1319 nilfs_close_segment_entry(ent, sufile);
1320
1321 list_add_tail(&ent->list, &sci->sc_active_segments);
1322 segbuf->sb_segent = NULL;
1323 return 0;
1324}
1325
1326static int nilfs_touch_segusage(struct inode *sufile, __u64 segnum)
1327{
1328 struct buffer_head *bh_su;
1329 struct nilfs_segment_usage *raw_su;
1330 int err;
1331
1332 err = nilfs_sufile_get_segment_usage(sufile, segnum, &raw_su, &bh_su);
1333 if (unlikely(err))
1334 return err;
1335 nilfs_mdt_mark_buffer_dirty(bh_su);
1336 nilfs_mdt_mark_dirty(sufile);
1337 nilfs_sufile_put_segment_usage(sufile, segnum, bh_su);
1338 return 0;
1339}
1340
1341static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1342 struct the_nilfs *nilfs)
1343{
1344 struct nilfs_segment_buffer *segbuf, *n;
1345 struct inode *sufile = nilfs->ns_sufile;
1346 __u64 nextnum;
1347 int err;
1348
1349 if (list_empty(&sci->sc_segbufs)) {
1350 segbuf = nilfs_segbuf_new(sci->sc_super);
1351 if (unlikely(!segbuf))
1352 return -ENOMEM;
1353 list_add(&segbuf->sb_list, &sci->sc_segbufs);
1354 } else
1355 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1356
1357 err = nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1358 nilfs->ns_pseg_offset, nilfs);
1359 if (unlikely(err))
1360 return err;
1361
1362 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1363 err = nilfs_segctor_terminate_segment(sci, segbuf, sufile);
1364 if (unlikely(err))
1365 return err;
1366
1367 nilfs_shift_to_next_segment(nilfs);
1368 err = nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1369 }
1370 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1371
1372 err = nilfs_touch_segusage(sufile, segbuf->sb_segnum);
1373 if (unlikely(err))
1374 return err;
1375
1376 if (nilfs->ns_segnum == nilfs->ns_nextnum) {
1377 /* Start from the head of a new full segment */
1378 err = nilfs_sufile_alloc(sufile, &nextnum);
1379 if (unlikely(err))
1380 return err;
1381 } else
1382 nextnum = nilfs->ns_nextnum;
1383
1384 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1385 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1386
1387 /* truncating segment buffers */
1388 list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs,
1389 sb_list) {
1390 list_del_init(&segbuf->sb_list);
1391 nilfs_segbuf_free(segbuf);
1392 }
1393 return err;
1394}
1395
1396static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1397 struct the_nilfs *nilfs, int nadd)
1398{
1399 struct nilfs_segment_buffer *segbuf, *prev, *n;
1400 struct inode *sufile = nilfs->ns_sufile;
1401 __u64 nextnextnum;
1402 LIST_HEAD(list);
1403 int err, ret, i;
1404
1405 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1406 /*
1407 * Since the segment specified with nextnum might be allocated during
1408 * the previous construction, the buffer including its segusage may
1409 * not be dirty. The following call ensures that the buffer is dirty
1410 * and will pin the buffer on memory until the sufile is written.
1411 */
1412 err = nilfs_touch_segusage(sufile, prev->sb_nextnum);
1413 if (unlikely(err))
1414 return err;
1415
1416 for (i = 0; i < nadd; i++) {
1417 /* extend segment info */
1418 err = -ENOMEM;
1419 segbuf = nilfs_segbuf_new(sci->sc_super);
1420 if (unlikely(!segbuf))
1421 goto failed;
1422
1423 /* map this buffer to region of segment on-disk */
1424 err = nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1425 if (unlikely(err))
1426 goto failed_segbuf;
1427
1428 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1429
1430 /* allocate the next next full segment */
1431 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1432 if (unlikely(err))
1433 goto failed_segbuf;
1434
1435 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1436 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1437
1438 list_add_tail(&segbuf->sb_list, &list);
1439 prev = segbuf;
1440 }
1441 list_splice(&list, sci->sc_segbufs.prev);
1442 return 0;
1443
1444 failed_segbuf:
1445 nilfs_segbuf_free(segbuf);
1446 failed:
1447 list_for_each_entry_safe(segbuf, n, &list, sb_list) {
1448 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1449 WARN_ON(ret); /* never fails */
9ff05123
RK		 1450 list_del_init(&segbuf->sb_list);
1451 nilfs_segbuf_free(segbuf);
1452 }
1453 return err;
1454}
1455
1456static void nilfs_segctor_free_incomplete_segments(struct nilfs_sc_info *sci,
1457 struct the_nilfs *nilfs)
1458{
1459 struct nilfs_segment_buffer *segbuf;
1460 int ret, done = 0;
1461
1462 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1463 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1464 ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum);
1f5abe7e 1465 WARN_ON(ret); /* never fails */
9ff05123
RK		 1466 }
1467 if (segbuf->sb_io_error) {
1468 /* Case 1: The first segment failed */
1469 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1470 /* Case 1a: Partial segment appended into an existing
1471 segment */
1472 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1473 segbuf->sb_fseg_end);
1474 else /* Case 1b: New full segment */
1475 set_nilfs_discontinued(nilfs);
1476 done++;
1477 }
1478
1479 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1480 ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum);
1f5abe7e 1481 WARN_ON(ret); /* never fails */
9ff05123
RK		 1482 if (!done && segbuf->sb_io_error) {
1483 if (segbuf->sb_segnum != nilfs->ns_nextnum)
1484 /* Case 2: extended segment (!= next) failed */
1485 nilfs_sufile_set_error(nilfs->ns_sufile,
1486 segbuf->sb_segnum);
1487 done++;
1488 }
1489 }
1490}
1491
1492static void nilfs_segctor_clear_segment_buffers(struct nilfs_sc_info *sci)
1493{
1494 struct nilfs_segment_buffer *segbuf;
1495
1496 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list)
1497 nilfs_segbuf_clear(segbuf);
1498 sci->sc_super_root = NULL;
1499}
1500
1501static void nilfs_segctor_destroy_segment_buffers(struct nilfs_sc_info *sci)
1502{
1503 struct nilfs_segment_buffer *segbuf;
1504
1505 while (!list_empty(&sci->sc_segbufs)) {
1506 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1507 list_del_init(&segbuf->sb_list);
1508 nilfs_segbuf_free(segbuf);
1509 }
1510 /* sci->sc_curseg = NULL; */
1511}
1512
1513static void nilfs_segctor_end_construction(struct nilfs_sc_info *sci,
1514 struct the_nilfs *nilfs, int err)
1515{
1516 if (unlikely(err)) {
1517 nilfs_segctor_free_incomplete_segments(sci, nilfs);
1518 nilfs_segctor_cancel_free_segments(sci, nilfs->ns_sufile);
1519 }
1520 nilfs_segctor_clear_segment_buffers(sci);
1521}
1522
1523static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1524 struct inode *sufile)
1525{
1526 struct nilfs_segment_buffer *segbuf;
1527 struct buffer_head *bh_su;
1528 struct nilfs_segment_usage *raw_su;
1529 unsigned long live_blocks;
1530 int ret;
1531
1532 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1533 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum,
1534 &raw_su, &bh_su);
1f5abe7e 1535 WARN_ON(ret); /* always succeed because bh_su is dirty */
9ff05123
RK		 1536 live_blocks = segbuf->sb_sum.nblocks +
1537 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1538 raw_su->su_lastmod = cpu_to_le64(sci->sc_seg_ctime);
1539 raw_su->su_nblocks = cpu_to_le32(live_blocks);
1540 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum,
1541 bh_su);
1542 }
1543}
1544
1545static void nilfs_segctor_cancel_segusage(struct nilfs_sc_info *sci,
1546 struct inode *sufile)
1547{
1548 struct nilfs_segment_buffer *segbuf;
1549 struct buffer_head *bh_su;
1550 struct nilfs_segment_usage *raw_su;
1551 int ret;
1552
1553 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1554 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum,
1555 &raw_su, &bh_su);
1f5abe7e 1556 WARN_ON(ret); /* always succeed because bh_su is dirty */
9ff05123
RK		 1557 raw_su->su_nblocks = cpu_to_le32(segbuf->sb_pseg_start -
1558 segbuf->sb_fseg_start);
1559 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, bh_su);
1560
1561 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1562 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum,
1563 &raw_su, &bh_su);
1f5abe7e 1564 WARN_ON(ret); /* always succeed */
9ff05123
RK		 1565 raw_su->su_nblocks = 0;
1566 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum,
1567 bh_su);
1568 }
1569}
1570
1571static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1572 struct nilfs_segment_buffer *last,
1573 struct inode *sufile)
1574{
1575 struct nilfs_segment_buffer *segbuf = last, *n;
1576 int ret;
1577
1578 list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs,
1579 sb_list) {
1580 list_del_init(&segbuf->sb_list);
1581 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1582 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1583 WARN_ON(ret);
9ff05123
RK		 1584 nilfs_segbuf_free(segbuf);
1585 }
1586}
1587
1588
1589static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1590 struct the_nilfs *nilfs, int mode)
1591{
1592 struct nilfs_cstage prev_stage = sci->sc_stage;
1593 int err, nadd = 1;
1594
1595 /* Collection retry loop */
1596 for (;;) {
1597 sci->sc_super_root = NULL;
1598 sci->sc_nblk_this_inc = 0;
1599 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1600
1601 err = nilfs_segctor_reset_segment_buffer(sci);
1602 if (unlikely(err))
1603 goto failed;
1604
1605 err = nilfs_segctor_collect_blocks(sci, mode);
1606 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1607 if (!err)
1608 break;
1609
1610 if (unlikely(err != -E2BIG))
1611 goto failed;
1612
1613 /* The current segment is filled up */
1614 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE)
1615 break;
1616
1617 nilfs_segctor_cancel_free_segments(sci, nilfs->ns_sufile);
1618 nilfs_segctor_clear_segment_buffers(sci);
1619
1620 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1621 if (unlikely(err))
1622 return err;
1623
1624 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1625 sci->sc_stage = prev_stage;
1626 }
1627 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1628 return 0;
1629
1630 failed:
1631 return err;
1632}
1633
1634static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1635 struct buffer_head *new_bh)
1636{
1637 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1638
1639 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1640 /* The caller must release old_bh */
1641}
1642
1643static int
1644nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1645 struct nilfs_segment_buffer *segbuf,
1646 int mode)
1647{
1648 struct inode *inode = NULL;
1649 sector_t blocknr;
1650 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1651 unsigned long nblocks = 0, ndatablk = 0;
1652 struct nilfs_sc_operations *sc_op = NULL;
1653 struct nilfs_segsum_pointer ssp;
1654 struct nilfs_finfo *finfo = NULL;
1655 union nilfs_binfo binfo;
1656 struct buffer_head *bh, *bh_org;
1657 ino_t ino = 0;
1658 int err = 0;
1659
1660 if (!nfinfo)
1661 goto out;
1662
1663 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1664 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1665 ssp.offset = sizeof(struct nilfs_segment_summary);
1666
1667 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1668 if (bh == sci->sc_super_root)
1669 break;
1670 if (!finfo) {
1671 finfo = nilfs_segctor_map_segsum_entry(
1672 sci, &ssp, sizeof(*finfo));
1673 ino = le64_to_cpu(finfo->fi_ino);
1674 nblocks = le32_to_cpu(finfo->fi_nblocks);
1675 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1676
1677 if (buffer_nilfs_node(bh))
1678 inode = NILFS_BTNC_I(bh->b_page->mapping);
1679 else
1680 inode = NILFS_AS_I(bh->b_page->mapping);
1681
1682 if (mode == SC_LSEG_DSYNC)
1683 sc_op = &nilfs_sc_dsync_ops;
1684 else if (ino == NILFS_DAT_INO)
1685 sc_op = &nilfs_sc_dat_ops;
1686 else /* file blocks */
1687 sc_op = &nilfs_sc_file_ops;
1688 }
1689 bh_org = bh;
1690 get_bh(bh_org);
1691 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1692 &binfo);
1693 if (bh != bh_org)
1694 nilfs_list_replace_buffer(bh_org, bh);
1695 brelse(bh_org);
1696 if (unlikely(err))
1697 goto failed_bmap;
1698
1699 if (ndatablk > 0)
1700 sc_op->write_data_binfo(sci, &ssp, &binfo);
1701 else
1702 sc_op->write_node_binfo(sci, &ssp, &binfo);
1703
1704 blocknr++;
1705 if (--nblocks == 0) {
1706 finfo = NULL;
1707 if (--nfinfo == 0)
1708 break;
1709 } else if (ndatablk > 0)
1710 ndatablk--;
1711 }
1712 out:
1713 return 0;
1714
1715 failed_bmap:
1716 err = nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super);
1717 return err;
1718}
1719
1720static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1721{
1722 struct nilfs_segment_buffer *segbuf;
1723 int err;
1724
1725 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1726 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1727 if (unlikely(err))
1728 return err;
1729 nilfs_segbuf_fill_in_segsum(segbuf);
1730 }
1731 return 0;
1732}
1733
1734static int
1735nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out)
1736{
1737 struct page *clone_page;
1738 struct buffer_head *bh, *head, *bh2;
1739 void *kaddr;
1740
1741 bh = head = page_buffers(page);
1742
1743 clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0);
1744 if (unlikely(!clone_page))
1745 return -ENOMEM;
1746
1747 bh2 = page_buffers(clone_page);
1748 kaddr = kmap_atomic(page, KM_USER0);
1749 do {
1750 if (list_empty(&bh->b_assoc_buffers))
1751 continue;
1752 get_bh(bh2);
1753 page_cache_get(clone_page); /* for each bh */
1754 memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size);
1755 bh2->b_blocknr = bh->b_blocknr;
1756 list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers);
1757 list_add_tail(&bh->b_assoc_buffers, out);
1758 } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head);
1759 kunmap_atomic(kaddr, KM_USER0);
1760
1761 if (!TestSetPageWriteback(clone_page))
1762 inc_zone_page_state(clone_page, NR_WRITEBACK);
1763 unlock_page(clone_page);
1764
1765 return 0;
1766}
1767
1768static int nilfs_test_page_to_be_frozen(struct page *page)
1769{
1770 struct address_space *mapping = page->mapping;
1771
1772 if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode))
1773 return 0;
1774
1775 if (page_mapped(page)) {
1776 ClearPageChecked(page);
1777 return 1;
1778 }
1779 return PageChecked(page);
1780}
1781
1782static int nilfs_begin_page_io(struct page *page, struct list_head *out)
1783{
1784 if (!page || PageWriteback(page))
1785 /* For split b-tree node pages, this function may be called
1786 twice. We ignore the 2nd or later calls by this check. */
1787 return 0;
1788
1789 lock_page(page);
1790 clear_page_dirty_for_io(page);
1791 set_page_writeback(page);
1792 unlock_page(page);
1793
1794 if (nilfs_test_page_to_be_frozen(page)) {
1795 int err = nilfs_copy_replace_page_buffers(page, out);
1796 if (unlikely(err))
1797 return err;
1798 }
1799 return 0;
1800}
1801
1802static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci,
1803 struct page **failed_page)
1804{
1805 struct nilfs_segment_buffer *segbuf;
1806 struct page *bd_page = NULL, *fs_page = NULL;
1807 struct list_head *list = &sci->sc_copied_buffers;
1808 int err;
1809
1810 *failed_page = NULL;
1811 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1812 struct buffer_head *bh;
1813
1814 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1815 b_assoc_buffers) {
1816 if (bh->b_page != bd_page) {
1817 if (bd_page) {
1818 lock_page(bd_page);
1819 clear_page_dirty_for_io(bd_page);
1820 set_page_writeback(bd_page);
1821 unlock_page(bd_page);
1822 }
1823 bd_page = bh->b_page;
1824 }
1825 }
1826
1827 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1828 b_assoc_buffers) {
1829 if (bh == sci->sc_super_root) {
1830 if (bh->b_page != bd_page) {
1831 lock_page(bd_page);
1832 clear_page_dirty_for_io(bd_page);
1833 set_page_writeback(bd_page);
1834 unlock_page(bd_page);
1835 bd_page = bh->b_page;
1836 }
1837 break;
1838 }
1839 if (bh->b_page != fs_page) {
1840 err = nilfs_begin_page_io(fs_page, list);
1841 if (unlikely(err)) {
1842 *failed_page = fs_page;
1843 goto out;
1844 }
1845 fs_page = bh->b_page;
1846 }
1847 }
1848 }
1849 if (bd_page) {
1850 lock_page(bd_page);
1851 clear_page_dirty_for_io(bd_page);
1852 set_page_writeback(bd_page);
1853 unlock_page(bd_page);
1854 }
1855 err = nilfs_begin_page_io(fs_page, list);
1856 if (unlikely(err))
1857 *failed_page = fs_page;
1858 out:
1859 return err;
1860}
1861
1862static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1863 struct backing_dev_info *bdi)
1864{
1865 struct nilfs_segment_buffer *segbuf;
1866 struct nilfs_write_info wi;
1867 int err, res;
1868
1869 wi.sb = sci->sc_super;
1870 wi.bh_sr = sci->sc_super_root;
1871 wi.bdi = bdi;
1872
1873 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1874 nilfs_segbuf_prepare_write(segbuf, &wi);
1875 err = nilfs_segbuf_write(segbuf, &wi);
1876
1877 res = nilfs_segbuf_wait(segbuf, &wi);
1878 err = unlikely(err) ? : res;
1879 if (unlikely(err))
1880 return err;
1881 }
1882 return 0;
1883}
1884
1885static int nilfs_page_has_uncleared_buffer(struct page *page)
1886{
1887 struct buffer_head *head, *bh;
1888
1889 head = bh = page_buffers(page);
1890 do {
1891 if (buffer_dirty(bh) && !list_empty(&bh->b_assoc_buffers))
1892 return 1;
1893 bh = bh->b_this_page;
1894 } while (bh != head);
1895 return 0;
1896}
1897
1898static void __nilfs_end_page_io(struct page *page, int err)
1899{
9ff05123
RK		 1900 if (!err) {
1901 if (!nilfs_page_buffers_clean(page))
1902 __set_page_dirty_nobuffers(page);
1903 ClearPageError(page);
1904 } else {
1905 __set_page_dirty_nobuffers(page);
1906 SetPageError(page);
1907 }
1908
1909 if (buffer_nilfs_allocated(page_buffers(page))) {
1910 if (TestClearPageWriteback(page))
1911 dec_zone_page_state(page, NR_WRITEBACK);
1912 } else
1913 end_page_writeback(page);
1914}
1915
1916static void nilfs_end_page_io(struct page *page, int err)
1917{
1918 if (!page)
1919 return;
1920
1921 if (buffer_nilfs_node(page_buffers(page)) &&
1922 nilfs_page_has_uncleared_buffer(page))
1923 /* For b-tree node pages, this function may be called twice
1924 or more because they might be split in a segment.
1925 This check assures that cleanup has been done for all
1926 buffers in a split btnode page. */
1927 return;
1928
1929 __nilfs_end_page_io(page, err);
1930}
1931
1932static void nilfs_clear_copied_buffers(struct list_head *list, int err)
1933{
1934 struct buffer_head *bh, *head;
1935 struct page *page;
1936
1937 while (!list_empty(list)) {
1938 bh = list_entry(list->next, struct buffer_head,
1939 b_assoc_buffers);
1940 page = bh->b_page;
1941 page_cache_get(page);
1942 head = bh = page_buffers(page);
1943 do {
1944 if (!list_empty(&bh->b_assoc_buffers)) {
1945 list_del_init(&bh->b_assoc_buffers);
1946 if (!err) {
1947 set_buffer_uptodate(bh);
1948 clear_buffer_dirty(bh);
1949 clear_buffer_nilfs_volatile(bh);
1950 }
1951 brelse(bh); /* for b_assoc_buffers */
1952 }
1953 } while ((bh = bh->b_this_page) != head);
1954
1955 __nilfs_end_page_io(page, err);
1956 page_cache_release(page);
1957 }
1958}
1959
1960static void nilfs_segctor_abort_write(struct nilfs_sc_info *sci,
1961 struct page *failed_page, int err)
1962{
1963 struct nilfs_segment_buffer *segbuf;
1964 struct page *bd_page = NULL, *fs_page = NULL;
1965
1966 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1967 struct buffer_head *bh;
1968
1969 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1970 b_assoc_buffers) {
1971 if (bh->b_page != bd_page) {
1972 if (bd_page)
1973 end_page_writeback(bd_page);
1974 bd_page = bh->b_page;
1975 }
1976 }
1977
1978 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1979 b_assoc_buffers) {
1980 if (bh == sci->sc_super_root) {
1981 if (bh->b_page != bd_page) {
1982 end_page_writeback(bd_page);
1983 bd_page = bh->b_page;
1984 }
1985 break;
1986 }
1987 if (bh->b_page != fs_page) {
1988 nilfs_end_page_io(fs_page, err);
1989 if (unlikely(fs_page == failed_page))
1990 goto done;
1991 fs_page = bh->b_page;
1992 }
1993 }
1994 }
1995 if (bd_page)
1996 end_page_writeback(bd_page);
1997
1998 nilfs_end_page_io(fs_page, err);
1999 done:
2000 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err);
2001}
2002
2003static void nilfs_set_next_segment(struct the_nilfs *nilfs,
2004 struct nilfs_segment_buffer *segbuf)
2005{
2006 nilfs->ns_segnum = segbuf->sb_segnum;
2007 nilfs->ns_nextnum = segbuf->sb_nextnum;
2008 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
2009 + segbuf->sb_sum.nblocks;
2010 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
2011 nilfs->ns_ctime = segbuf->sb_sum.ctime;
2012}
2013
2014static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
2015{
2016 struct nilfs_segment_buffer *segbuf;
2017 struct page *bd_page = NULL, *fs_page = NULL;
2018 struct nilfs_sb_info *sbi = sci->sc_sbi;
2019 struct the_nilfs *nilfs = sbi->s_nilfs;
2020 int update_sr = (sci->sc_super_root != NULL);
2021
2022 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
2023 struct buffer_head *bh;
2024
2025 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
2026 b_assoc_buffers) {
2027 set_buffer_uptodate(bh);
2028 clear_buffer_dirty(bh);
2029 if (bh->b_page != bd_page) {
2030 if (bd_page)
2031 end_page_writeback(bd_page);
2032 bd_page = bh->b_page;
2033 }
2034 }
2035 /*
2036 * We assume that the buffers which belong to the same page
2037 * continue over the buffer list.
2038 * Under this assumption, the last BHs of pages is
2039 * identifiable by the discontinuity of bh->b_page
2040 * (page != fs_page).
2041 *
2042 * For B-tree node blocks, however, this assumption is not
2043 * guaranteed. The cleanup code of B-tree node pages needs
2044 * special care.
2045 */
2046 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
2047 b_assoc_buffers) {
2048 set_buffer_uptodate(bh);
2049 clear_buffer_dirty(bh);
2050 clear_buffer_nilfs_volatile(bh);
2051 if (bh == sci->sc_super_root) {
2052 if (bh->b_page != bd_page) {
2053 end_page_writeback(bd_page);
2054 bd_page = bh->b_page;
2055 }
2056 break;
2057 }
2058 if (bh->b_page != fs_page) {
2059 nilfs_end_page_io(fs_page, 0);
2060 fs_page = bh->b_page;
2061 }
2062 }
2063
2064 if (!NILFS_SEG_SIMPLEX(&segbuf->sb_sum)) {
2065 if (NILFS_SEG_LOGBGN(&segbuf->sb_sum)) {
2066 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
2067 sci->sc_lseg_stime = jiffies;
2068 }
2069 if (NILFS_SEG_LOGEND(&segbuf->sb_sum))
2070 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
2071 }
2072 }
2073 /*
2074 * Since pages may continue over multiple segment buffers,
2075 * end of the last page must be checked outside of the loop.
2076 */
2077 if (bd_page)
2078 end_page_writeback(bd_page);
2079
2080 nilfs_end_page_io(fs_page, 0);
2081
2082 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0);
2083
2084 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
2085
2086 if (nilfs_doing_gc()) {
2087 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
2088 if (update_sr)
2089 nilfs_commit_gcdat_inode(nilfs);
1088dcf4 2090 } else
9ff05123 2091 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
9ff05123
RK		 2092
2093 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
2094
2095 segbuf = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
2096 nilfs_set_next_segment(nilfs, segbuf);
2097
2098 if (update_sr) {
2099 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
2100 segbuf->sb_sum.seg_seq, nilfs->ns_cno);
2101
c96fa464 2102 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
9ff05123
RK		 2103 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2104 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
2105 } else
2106 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
2107}
2108
2109static int nilfs_segctor_check_in_files(struct nilfs_sc_info *sci,
2110 struct nilfs_sb_info *sbi)
2111{
2112 struct nilfs_inode_info *ii, *n;
2113 __u64 cno = sbi->s_nilfs->ns_cno;
2114
2115 spin_lock(&sbi->s_inode_lock);
2116 retry:
2117 list_for_each_entry_safe(ii, n, &sbi->s_dirty_files, i_dirty) {
2118 if (!ii->i_bh) {
2119 struct buffer_head *ibh;
2120 int err;
2121
2122 spin_unlock(&sbi->s_inode_lock);
2123 err = nilfs_ifile_get_inode_block(
2124 sbi->s_ifile, ii->vfs_inode.i_ino, &ibh);
2125 if (unlikely(err)) {
2126 nilfs_warning(sbi->s_super, __func__,
2127 "failed to get inode block.\n");
2128 return err;
2129 }
2130 nilfs_mdt_mark_buffer_dirty(ibh);
2131 nilfs_mdt_mark_dirty(sbi->s_ifile);
2132 spin_lock(&sbi->s_inode_lock);
2133 if (likely(!ii->i_bh))
2134 ii->i_bh = ibh;
2135 else
2136 brelse(ibh);
2137 goto retry;
2138 }
2139 ii->i_cno = cno;
2140
2141 clear_bit(NILFS_I_QUEUED, &ii->i_state);
2142 set_bit(NILFS_I_BUSY, &ii->i_state);
2143 list_del(&ii->i_dirty);
2144 list_add_tail(&ii->i_dirty, &sci->sc_dirty_files);
2145 }
2146 spin_unlock(&sbi->s_inode_lock);
2147
2148 NILFS_I(sbi->s_ifile)->i_cno = cno;
2149
2150 return 0;
2151}
2152
2153static void nilfs_segctor_check_out_files(struct nilfs_sc_info *sci,
2154 struct nilfs_sb_info *sbi)
2155{
2156 struct nilfs_transaction_info *ti = current->journal_info;
2157 struct nilfs_inode_info *ii, *n;
2158 __u64 cno = sbi->s_nilfs->ns_cno;
2159
2160 spin_lock(&sbi->s_inode_lock);
2161 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2162 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
2163 test_bit(NILFS_I_DIRTY, &ii->i_state)) {
2164 /* The current checkpoint number (=nilfs->ns_cno) is
2165 changed between check-in and check-out only if the
2166 super root is written out. So, we can update i_cno
2167 for the inodes that remain in the dirty list. */
2168 ii->i_cno = cno;
2169 continue;
2170 }
2171 clear_bit(NILFS_I_BUSY, &ii->i_state);
2172 brelse(ii->i_bh);
2173 ii->i_bh = NULL;
2174 list_del(&ii->i_dirty);
2175 list_add_tail(&ii->i_dirty, &ti->ti_garbage);
2176 }
2177 spin_unlock(&sbi->s_inode_lock);
2178}
2179
2180/*
2181 * Nasty routines to manipulate active flags on sufile.
2182 * These would be removed in a future release.
2183 */
2184static void nilfs_segctor_reactivate_segments(struct nilfs_sc_info *sci,
2185 struct the_nilfs *nilfs)
2186{
2187 struct nilfs_segment_buffer *segbuf, *last;
2188 struct nilfs_segment_entry *ent, *n;
2189 struct inode *sufile = nilfs->ns_sufile;
2190 struct list_head *head;
2191
2192 last = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
2193 nilfs_for_each_segbuf_before(segbuf, last, &sci->sc_segbufs) {
2194 ent = segbuf->sb_segent;
2195 if (!ent)
2196 break; /* ignore unmapped segments (should check it?)*/
2197 nilfs_segment_usage_set_active(ent->raw_su);
2198 nilfs_close_segment_entry(ent, sufile);
2199 }
2200
2201 head = &sci->sc_active_segments;
2202 list_for_each_entry_safe(ent, n, head, list) {
2203 nilfs_segment_usage_set_active(ent->raw_su);
2204 nilfs_close_segment_entry(ent, sufile);
2205 }
9ff05123
RK		 2206}
2207
2208static int nilfs_segctor_deactivate_segments(struct nilfs_sc_info *sci,
2209 struct the_nilfs *nilfs)
2210{
2211 struct nilfs_segment_buffer *segbuf, *last;
2212 struct nilfs_segment_entry *ent;
2213 struct inode *sufile = nilfs->ns_sufile;
9ff05123
RK		 2214 int err;
2215
2216 last = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
2217 nilfs_for_each_segbuf_before(segbuf, last, &sci->sc_segbufs) {
2218 /*
2219 * Deactivate ongoing full segments. The last segment is kept
2220 * active because it is a start point of recovery, and is not
2221 * relocatable until the super block points to a newer
2222 * checkpoint.
2223 */
2224 ent = segbuf->sb_segent;
2225 if (!ent)
2226 break; /* ignore unmapped segments (should check it?)*/
2227 err = nilfs_open_segment_entry(ent, sufile);
2228 if (unlikely(err))
2229 goto failed;
2230 nilfs_segment_usage_clear_active(ent->raw_su);
2231 BUG_ON(!buffer_dirty(ent->bh_su));
2232 }
2233
2c2e52fc 2234 list_for_each_entry(ent, &sci->sc_active_segments, list) {
9ff05123
RK		 2235 err = nilfs_open_segment_entry(ent, sufile);
2236 if (unlikely(err))
2237 goto failed;
2238 nilfs_segment_usage_clear_active(ent->raw_su);
1f5abe7e 2239 WARN_ON(!buffer_dirty(ent->bh_su));
9ff05123 2240 }
9ff05123
RK		 2241 return 0;
2242
2243 failed:
2244 nilfs_segctor_reactivate_segments(sci, nilfs);
2245 return err;
2246}
2247
2248static void nilfs_segctor_bead_completed_segments(struct nilfs_sc_info *sci)
2249{
2250 struct nilfs_segment_buffer *segbuf, *last;
2251 struct nilfs_segment_entry *ent;
2252
2253 /* move each segbuf->sb_segent to the list of used active segments */
2254 last = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
2255 nilfs_for_each_segbuf_before(segbuf, last, &sci->sc_segbufs) {
2256 ent = segbuf->sb_segent;
2257 if (!ent)
2258 break; /* ignore unmapped segments (should check it?)*/
2259 list_add_tail(&ent->list, &sci->sc_active_segments);
2260 segbuf->sb_segent = NULL;
2261 }
2262}
2263
2c2e52fc
RK		 2264static void nilfs_segctor_commit_deactivate_segments(struct nilfs_sc_info *sci,
2265 struct the_nilfs *nilfs)
9ff05123 2266{
2c2e52fc 2267 struct nilfs_segment_entry *ent, *n;
9ff05123 2268
2c2e52fc
RK		 2269 list_for_each_entry_safe(ent, n, &sci->sc_active_segments, list) {
2270 list_del(&ent->list);
2271 nilfs_close_segment_entry(ent, nilfs->ns_sufile);
2272 nilfs_free_segment_entry(ent);
9ff05123
RK		 2273 }
2274}
2275
2276/*
2277 * Main procedure of segment constructor
2278 */
2279static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2280{
2281 struct nilfs_sb_info *sbi = sci->sc_sbi;
2282 struct the_nilfs *nilfs = sbi->s_nilfs;
2283 struct page *failed_page;
2284 int err, has_sr = 0;
2285
2286 sci->sc_stage.scnt = NILFS_ST_INIT;
2287
2288 err = nilfs_segctor_check_in_files(sci, sbi);
2289 if (unlikely(err))
2290 goto out;
2291
2292 if (nilfs_test_metadata_dirty(sbi))
2293 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2294
2295 if (nilfs_segctor_clean(sci))
2296 goto out;
2297
2298 do {
2299 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2300
2301 err = nilfs_segctor_begin_construction(sci, nilfs);
2302 if (unlikely(err))
2303 goto out;
2304
2305 /* Update time stamp */
2306 sci->sc_seg_ctime = get_seconds();
2307
2308 err = nilfs_segctor_collect(sci, nilfs, mode);
2309 if (unlikely(err))
2310 goto failed;
2311
2312 has_sr = (sci->sc_super_root != NULL);
2313
2314 /* Avoid empty segment */
2315 if (sci->sc_stage.scnt == NILFS_ST_DONE &&
2316 NILFS_SEG_EMPTY(&sci->sc_curseg->sb_sum)) {
9ff05123
RK		 2317 nilfs_segctor_end_construction(sci, nilfs, 1);
2318 goto out;
2319 }
2320
2321 err = nilfs_segctor_assign(sci, mode);
2322 if (unlikely(err))
2323 goto failed;
2324
2325 if (has_sr) {
2326 err = nilfs_segctor_deactivate_segments(sci, nilfs);
2327 if (unlikely(err))
2328 goto failed;
2329 }
2330 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2331 nilfs_segctor_fill_in_file_bmap(sci, sbi->s_ifile);
2332
2333 if (has_sr) {
2334 err = nilfs_segctor_fill_in_checkpoint(sci);
2335 if (unlikely(err))
2336 goto failed_to_make_up;
2337
2338 nilfs_segctor_fill_in_super_root(sci, nilfs);
2339 }
2340 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2341
2342 /* Write partial segments */
2343 err = nilfs_segctor_prepare_write(sci, &failed_page);
2344 if (unlikely(err))
2345 goto failed_to_write;
2346
2347 nilfs_segctor_fill_in_checksums(sci, nilfs->ns_crc_seed);
2348
2349 err = nilfs_segctor_write(sci, nilfs->ns_bdi);
2350 if (unlikely(err))
2351 goto failed_to_write;
2352
2353 nilfs_segctor_complete_write(sci);
2354
2355 /* Commit segments */
2356 nilfs_segctor_bead_completed_segments(sci);
2357 if (has_sr) {
2358 down_write(&nilfs->ns_sem);
2359 nilfs_update_last_segment(sbi, 1);
9ff05123 2360 up_write(&nilfs->ns_sem);
2c2e52fc 2361 nilfs_segctor_commit_deactivate_segments(sci, nilfs);
9ff05123
RK		 2362 nilfs_segctor_commit_free_segments(sci);
2363 nilfs_segctor_clear_metadata_dirty(sci);
2364 }
2365
2366 nilfs_segctor_end_construction(sci, nilfs, 0);
2367
2368 } while (sci->sc_stage.scnt != NILFS_ST_DONE);
2369
9ff05123
RK		 2370 out:
2371 nilfs_segctor_destroy_segment_buffers(sci);
2372 nilfs_segctor_check_out_files(sci, sbi);
2373 return err;
2374
2375 failed_to_write:
2376 nilfs_segctor_abort_write(sci, failed_page, err);
2377 nilfs_segctor_cancel_segusage(sci, nilfs->ns_sufile);
2378
2379 failed_to_make_up:
2380 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2381 nilfs_redirty_inodes(&sci->sc_dirty_files);
2382 if (has_sr)
2383 nilfs_segctor_reactivate_segments(sci, nilfs);
2384
2385 failed:
2386 if (nilfs_doing_gc())
2387 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2388 nilfs_segctor_end_construction(sci, nilfs, err);
2389 goto out;
2390}
2391
2392/**
2393 * nilfs_secgtor_start_timer - set timer of background write
2394 * @sci: nilfs_sc_info
2395 *
2396 * If the timer has already been set, it ignores the new request.
2397 * This function MUST be called within a section locking the segment
2398 * semaphore.
2399 */
2400static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2401{
2402 spin_lock(&sci->sc_state_lock);
2403 if (sci->sc_timer && !(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2404 sci->sc_timer->expires = jiffies + sci->sc_interval;
2405 add_timer(sci->sc_timer);
2406 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2407 }
2408 spin_unlock(&sci->sc_state_lock);
2409}
2410
2411static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2412{
2413 spin_lock(&sci->sc_state_lock);
2414 if (!(sci->sc_flush_request & (1 << bn))) {
2415 unsigned long prev_req = sci->sc_flush_request;
2416
2417 sci->sc_flush_request |= (1 << bn);
2418 if (!prev_req)
2419 wake_up(&sci->sc_wait_daemon);
2420 }
2421 spin_unlock(&sci->sc_state_lock);
2422}
2423
2424/**
2425 * nilfs_flush_segment - trigger a segment construction for resource control
2426 * @sb: super block
2427 * @ino: inode number of the file to be flushed out.
2428 */
2429void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2430{
2431 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2432 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2433
2434 if (!sci || nilfs_doing_construction())
2435 return;
2436 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2437 /* assign bit 0 to data files */
2438}
2439
2440int nilfs_segctor_add_segments_to_be_freed(struct nilfs_sc_info *sci,
2441 __u64 *segnum, size_t nsegs)
2442{
2443 struct nilfs_segment_entry *ent;
2444 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
2445 struct inode *sufile = nilfs->ns_sufile;
2446 LIST_HEAD(list);
2447 __u64 *pnum;
9ff05123 2448 size_t i;
1f5abe7e 2449 int err;
9ff05123
RK		 2450
2451 for (pnum = segnum, i = 0; i < nsegs; pnum++, i++) {
2452 ent = nilfs_alloc_segment_entry(*pnum);
2453 if (unlikely(!ent)) {
2454 err = -ENOMEM;
2455 goto failed;
2456 }
2457 list_add_tail(&ent->list, &list);
2458
2459 err = nilfs_open_segment_entry(ent, sufile);
2460 if (unlikely(err))
2461 goto failed;
2462
1f5abe7e
RK		 2463 if (unlikely(!nilfs_segment_usage_dirty(ent->raw_su)))
2464 printk(KERN_WARNING "NILFS: unused segment is "
2465 "requested to be cleaned (segnum=%llu)\n",
2466 (unsigned long long)ent->segnum);
9ff05123
RK		 2467 nilfs_close_segment_entry(ent, sufile);
2468 }
9ff05123
RK		 2469 list_splice(&list, sci->sc_cleaning_segments.prev);
2470 return 0;
2471
2472 failed:
2473 nilfs_dispose_segment_list(&list);
2474 return err;
2475}
2476
2477void nilfs_segctor_clear_segments_to_be_freed(struct nilfs_sc_info *sci)
2478{
2479 nilfs_dispose_segment_list(&sci->sc_cleaning_segments);
2480}
2481
2482struct nilfs_segctor_wait_request {
2483 wait_queue_t wq;
2484 __u32 seq;
2485 int err;
2486 atomic_t done;
2487};
2488
2489static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2490{
2491 struct nilfs_segctor_wait_request wait_req;
2492 int err = 0;
2493
2494 spin_lock(&sci->sc_state_lock);
2495 init_wait(&wait_req.wq);
2496 wait_req.err = 0;
2497 atomic_set(&wait_req.done, 0);
2498 wait_req.seq = ++sci->sc_seq_request;
2499 spin_unlock(&sci->sc_state_lock);
2500
2501 init_waitqueue_entry(&wait_req.wq, current);
2502 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2503 set_current_state(TASK_INTERRUPTIBLE);
2504 wake_up(&sci->sc_wait_daemon);
2505
2506 for (;;) {
2507 if (atomic_read(&wait_req.done)) {
2508 err = wait_req.err;
2509 break;
2510 }
2511 if (!signal_pending(current)) {
2512 schedule();
2513 continue;
2514 }
2515 err = -ERESTARTSYS;
2516 break;
2517 }
2518 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2519 return err;
2520}
2521
2522static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2523{
2524 struct nilfs_segctor_wait_request *wrq, *n;
2525 unsigned long flags;
2526
2527 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2528 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2529 wq.task_list) {
2530 if (!atomic_read(&wrq->done) &&
2531 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2532 wrq->err = err;
2533 atomic_set(&wrq->done, 1);
2534 }
2535 if (atomic_read(&wrq->done)) {
2536 wrq->wq.func(&wrq->wq,
2537 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2538 0, NULL);
2539 }
2540 }
2541 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2542}
2543
2544/**
2545 * nilfs_construct_segment - construct a logical segment
2546 * @sb: super block
2547 *
2548 * Return Value: On success, 0 is retured. On errors, one of the following
2549 * negative error code is returned.
2550 *
2551 * %-EROFS - Read only filesystem.
2552 *
2553 * %-EIO - I/O error
2554 *
2555 * %-ENOSPC - No space left on device (only in a panic state).
2556 *
2557 * %-ERESTARTSYS - Interrupted.
2558 *
2559 * %-ENOMEM - Insufficient memory available.
2560 */
2561int nilfs_construct_segment(struct super_block *sb)
2562{
2563 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2564 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2565 struct nilfs_transaction_info *ti;
2566 int err;
2567
2568 if (!sci)
2569 return -EROFS;
2570
2571 /* A call inside transactions causes a deadlock. */
2572 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2573
2574 err = nilfs_segctor_sync(sci);
2575 return err;
2576}
2577
2578/**
2579 * nilfs_construct_dsync_segment - construct a data-only logical segment
2580 * @sb: super block
f30bf3e4
RK		 2581 * @inode: inode whose data blocks should be written out
2582 * @start: start byte offset
2583 * @end: end byte offset (inclusive)
9ff05123
RK		 2584 *
2585 * Return Value: On success, 0 is retured. On errors, one of the following
2586 * negative error code is returned.
2587 *
2588 * %-EROFS - Read only filesystem.
2589 *
2590 * %-EIO - I/O error
2591 *
2592 * %-ENOSPC - No space left on device (only in a panic state).
2593 *
2594 * %-ERESTARTSYS - Interrupted.
2595 *
2596 * %-ENOMEM - Insufficient memory available.
2597 */
f30bf3e4
RK		 2598int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2599 loff_t start, loff_t end)
9ff05123
RK		 2600{
2601 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2602 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2603 struct nilfs_inode_info *ii;
2604 struct nilfs_transaction_info ti;
2605 int err = 0;
2606
2607 if (!sci)
2608 return -EROFS;
2609
2610 nilfs_transaction_lock(sbi, &ti, 0);
2611
2612 ii = NILFS_I(inode);
2613 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) ||
2614 nilfs_test_opt(sbi, STRICT_ORDER) ||
2615 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2616 nilfs_discontinued(sbi->s_nilfs)) {
2617 nilfs_transaction_unlock(sbi);
2618 err = nilfs_segctor_sync(sci);
2619 return err;
2620 }
2621
2622 spin_lock(&sbi->s_inode_lock);
2623 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2624 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2625 spin_unlock(&sbi->s_inode_lock);
2626 nilfs_transaction_unlock(sbi);
2627 return 0;
2628 }
2629 spin_unlock(&sbi->s_inode_lock);
f30bf3e4
RK		 2630 sci->sc_dsync_inode = ii;
2631 sci->sc_dsync_start = start;
2632 sci->sc_dsync_end = end;
9ff05123
RK		 2633
2634 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2635
2636 nilfs_transaction_unlock(sbi);
2637 return err;
2638}
2639
2640struct nilfs_segctor_req {
2641 int mode;
2642 __u32 seq_accepted;
2643 int sc_err; /* construction failure */
2644 int sb_err; /* super block writeback failure */
2645};
2646
2647#define FLUSH_FILE_BIT (0x1) /* data file only */
2648#define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2649
2650static void nilfs_segctor_accept(struct nilfs_sc_info *sci,
2651 struct nilfs_segctor_req *req)
2652{
9ff05123
RK		 2653 req->sc_err = req->sb_err = 0;
2654 spin_lock(&sci->sc_state_lock);
2655 req->seq_accepted = sci->sc_seq_request;
2656 spin_unlock(&sci->sc_state_lock);
2657
2658 if (sci->sc_timer)
2659 del_timer_sync(sci->sc_timer);
2660}
2661
2662static void nilfs_segctor_notify(struct nilfs_sc_info *sci,
2663 struct nilfs_segctor_req *req)
2664{
2665 /* Clear requests (even when the construction failed) */
2666 spin_lock(&sci->sc_state_lock);
2667
2668 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2669
2670 if (req->mode == SC_LSEG_SR) {
2671 sci->sc_seq_done = req->seq_accepted;
2672 nilfs_segctor_wakeup(sci, req->sc_err ? : req->sb_err);
2673 sci->sc_flush_request = 0;
2674 } else if (req->mode == SC_FLUSH_FILE)
2675 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2676 else if (req->mode == SC_FLUSH_DAT)
2677 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2678
2679 spin_unlock(&sci->sc_state_lock);
2680}
2681
2682static int nilfs_segctor_construct(struct nilfs_sc_info *sci,
2683 struct nilfs_segctor_req *req)
2684{
2685 struct nilfs_sb_info *sbi = sci->sc_sbi;
2686 struct the_nilfs *nilfs = sbi->s_nilfs;
2687 int err = 0;
2688
2689 if (nilfs_discontinued(nilfs))
2690 req->mode = SC_LSEG_SR;
2691 if (!nilfs_segctor_confirm(sci)) {
2692 err = nilfs_segctor_do_construct(sci, req->mode);
2693 req->sc_err = err;
2694 }
2695 if (likely(!err)) {
2696 if (req->mode != SC_FLUSH_DAT)
2697 atomic_set(&nilfs->ns_ndirtyblks, 0);
2698 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2699 nilfs_discontinued(nilfs)) {
2700 down_write(&nilfs->ns_sem);
2701 req->sb_err = nilfs_commit_super(sbi);
2702 up_write(&nilfs->ns_sem);
2703 }
2704 }
2705 return err;
2706}
2707
2708static void nilfs_construction_timeout(unsigned long data)
2709{
2710 struct task_struct *p = (struct task_struct *)data;
2711 wake_up_process(p);
2712}
2713
2714static void
2715nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2716{
2717 struct nilfs_inode_info *ii, *n;
2718
2719 list_for_each_entry_safe(ii, n, head, i_dirty) {
2720 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2721 continue;
2722 hlist_del_init(&ii->vfs_inode.i_hash);
2723 list_del_init(&ii->i_dirty);
2724 nilfs_clear_gcinode(&ii->vfs_inode);
2725 }
2726}
2727
2728int nilfs_clean_segments(struct super_block *sb, void __user *argp)
2729{
2730 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2731 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2732 struct the_nilfs *nilfs = sbi->s_nilfs;
2733 struct nilfs_transaction_info ti;
2734 struct nilfs_segctor_req req = { .mode = SC_LSEG_SR };
2735 int err;
2736
2737 if (unlikely(!sci))
2738 return -EROFS;
2739
2740 nilfs_transaction_lock(sbi, &ti, 1);
2741
2742 err = nilfs_init_gcdat_inode(nilfs);
2743 if (unlikely(err))
2744 goto out_unlock;
2745 err = nilfs_ioctl_prepare_clean_segments(nilfs, argp);
2746 if (unlikely(err))
2747 goto out_unlock;
2748
2749 list_splice_init(&nilfs->ns_gc_inodes, sci->sc_gc_inodes.prev);
2750
2751 for (;;) {
2752 nilfs_segctor_accept(sci, &req);
2753 err = nilfs_segctor_construct(sci, &req);
2754 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2755 nilfs_segctor_notify(sci, &req);
2756
2757 if (likely(!err))
2758 break;
2759
2760 nilfs_warning(sb, __func__,
2761 "segment construction failed. (err=%d)", err);
2762 set_current_state(TASK_INTERRUPTIBLE);
2763 schedule_timeout(sci->sc_interval);
2764 }
2765
2766 out_unlock:
2767 nilfs_clear_gcdat_inode(nilfs);
2768 nilfs_transaction_unlock(sbi);
2769 return err;
2770}
2771
2772static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2773{
2774 struct nilfs_sb_info *sbi = sci->sc_sbi;
2775 struct nilfs_transaction_info ti;
2776 struct nilfs_segctor_req req = { .mode = mode };
2777
2778 nilfs_transaction_lock(sbi, &ti, 0);
2779
2780 nilfs_segctor_accept(sci, &req);
2781 nilfs_segctor_construct(sci, &req);
2782 nilfs_segctor_notify(sci, &req);
2783
2784 /*
2785 * Unclosed segment should be retried. We do this using sc_timer.
2786 * Timeout of sc_timer will invoke complete construction which leads
2787 * to close the current logical segment.
2788 */
2789 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2790 nilfs_segctor_start_timer(sci);
2791
2792 nilfs_transaction_unlock(sbi);
2793}
2794
2795static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2796{
2797 int mode = 0;
2798 int err;
2799
2800 spin_lock(&sci->sc_state_lock);
2801 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2802 SC_FLUSH_DAT : SC_FLUSH_FILE;
2803 spin_unlock(&sci->sc_state_lock);
2804
2805 if (mode) {
2806 err = nilfs_segctor_do_construct(sci, mode);
2807
2808 spin_lock(&sci->sc_state_lock);
2809 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2810 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2811 spin_unlock(&sci->sc_state_lock);
2812 }
2813 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2814}
2815
2816static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2817{
2818 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2819 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2820 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2821 return SC_FLUSH_FILE;
2822 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2823 return SC_FLUSH_DAT;
2824 }
2825 return SC_LSEG_SR;
2826}
2827
2828/**
2829 * nilfs_segctor_thread - main loop of the segment constructor thread.
2830 * @arg: pointer to a struct nilfs_sc_info.
2831 *
2832 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2833 * to execute segment constructions.
2834 */
2835static int nilfs_segctor_thread(void *arg)
2836{
2837 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2838 struct timer_list timer;
2839 int timeout = 0;
2840
2841 init_timer(&timer);
2842 timer.data = (unsigned long)current;
2843 timer.function = nilfs_construction_timeout;
2844 sci->sc_timer = &timer;
2845
2846 /* start sync. */
2847 sci->sc_task = current;
2848 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2849 printk(KERN_INFO
2850 "segctord starting. Construction interval = %lu seconds, "
2851 "CP frequency < %lu seconds\n",
2852 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2853
2854 spin_lock(&sci->sc_state_lock);
2855 loop:
2856 for (;;) {
2857 int mode;
2858
2859 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2860 goto end_thread;
2861
2862 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2863 mode = SC_LSEG_SR;
2864 else if (!sci->sc_flush_request)
2865 break;
2866 else
2867 mode = nilfs_segctor_flush_mode(sci);
2868
2869 spin_unlock(&sci->sc_state_lock);
2870 nilfs_segctor_thread_construct(sci, mode);
2871 spin_lock(&sci->sc_state_lock);
2872 timeout = 0;
2873 }
2874
2875
2876 if (freezing(current)) {
2877 spin_unlock(&sci->sc_state_lock);
2878 refrigerator();
2879 spin_lock(&sci->sc_state_lock);
2880 } else {
2881 DEFINE_WAIT(wait);
2882 int should_sleep = 1;
2883
2884 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2885 TASK_INTERRUPTIBLE);
2886
2887 if (sci->sc_seq_request != sci->sc_seq_done)
2888 should_sleep = 0;
2889 else if (sci->sc_flush_request)
2890 should_sleep = 0;
2891 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2892 should_sleep = time_before(jiffies,
2893 sci->sc_timer->expires);
2894
2895 if (should_sleep) {
2896 spin_unlock(&sci->sc_state_lock);
2897 schedule();
2898 spin_lock(&sci->sc_state_lock);
2899 }
2900 finish_wait(&sci->sc_wait_daemon, &wait);
2901 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2902 time_after_eq(jiffies, sci->sc_timer->expires));
2903 }
2904 goto loop;
2905
2906 end_thread:
2907 spin_unlock(&sci->sc_state_lock);
2908 del_timer_sync(sci->sc_timer);
2909 sci->sc_timer = NULL;
2910
2911 /* end sync. */
2912 sci->sc_task = NULL;
2913 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2914 return 0;
2915}
2916
2917static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2918{
2919 struct task_struct *t;
2920
2921 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2922 if (IS_ERR(t)) {
2923 int err = PTR_ERR(t);
2924
2925 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2926 err);
2927 return err;
2928 }
2929 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2930 return 0;
2931}
2932
2933static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2934{
2935 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2936
2937 while (sci->sc_task) {
2938 wake_up(&sci->sc_wait_daemon);
2939 spin_unlock(&sci->sc_state_lock);
2940 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2941 spin_lock(&sci->sc_state_lock);
2942 }
2943}
2944
2945static int nilfs_segctor_init(struct nilfs_sc_info *sci,
2946 struct nilfs_recovery_info *ri)
2947{
2948 int err;
9ff05123
RK		 2949
2950 sci->sc_seq_done = sci->sc_seq_request;
2951 if (ri)
2952 list_splice_init(&ri->ri_used_segments,
2953 sci->sc_active_segments.prev);
2954
2955 err = nilfs_segctor_start_thread(sci);
2956 if (err) {
2957 if (ri)
2958 list_splice_init(&sci->sc_active_segments,
2959 ri->ri_used_segments.prev);
9ff05123
RK		 2960 }
2961 return err;
2962}
2963
2964/*
2965 * Setup & clean-up functions
2966 */
2967static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi)
2968{
2969 struct nilfs_sc_info *sci;
2970
2971 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2972 if (!sci)
2973 return NULL;
2974
2975 sci->sc_sbi = sbi;
2976 sci->sc_super = sbi->s_super;
2977
2978 init_waitqueue_head(&sci->sc_wait_request);
2979 init_waitqueue_head(&sci->sc_wait_daemon);
2980 init_waitqueue_head(&sci->sc_wait_task);
2981 spin_lock_init(&sci->sc_state_lock);
2982 INIT_LIST_HEAD(&sci->sc_dirty_files);
2983 INIT_LIST_HEAD(&sci->sc_segbufs);
2984 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2985 INIT_LIST_HEAD(&sci->sc_active_segments);
2986 INIT_LIST_HEAD(&sci->sc_cleaning_segments);
2987 INIT_LIST_HEAD(&sci->sc_copied_buffers);
2988
2989 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2990 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2991 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2992
2993 if (sbi->s_interval)
2994 sci->sc_interval = sbi->s_interval;
2995 if (sbi->s_watermark)
2996 sci->sc_watermark = sbi->s_watermark;
2997 return sci;
2998}
2999
3000static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
3001{
3002 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
3003
3004 /* The segctord thread was stopped and its timer was removed.
3005 But some tasks remain. */
3006 do {
3007 struct nilfs_sb_info *sbi = sci->sc_sbi;
3008 struct nilfs_transaction_info ti;
3009 struct nilfs_segctor_req req = { .mode = SC_LSEG_SR };
3010
3011 nilfs_transaction_lock(sbi, &ti, 0);
3012 nilfs_segctor_accept(sci, &req);
3013 ret = nilfs_segctor_construct(sci, &req);
3014 nilfs_segctor_notify(sci, &req);
3015 nilfs_transaction_unlock(sbi);
3016
3017 } while (ret && retrycount-- > 0);
3018}
3019
3020/**
3021 * nilfs_segctor_destroy - destroy the segment constructor.
3022 * @sci: nilfs_sc_info
3023 *
3024 * nilfs_segctor_destroy() kills the segctord thread and frees
3025 * the nilfs_sc_info struct.
3026 * Caller must hold the segment semaphore.
3027 */
3028static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
3029{
3030 struct nilfs_sb_info *sbi = sci->sc_sbi;
3031 int flag;
3032
3033 up_write(&sbi->s_nilfs->ns_segctor_sem);
3034
3035 spin_lock(&sci->sc_state_lock);
3036 nilfs_segctor_kill_thread(sci);
3037 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
3038 || sci->sc_seq_request != sci->sc_seq_done);
3039 spin_unlock(&sci->sc_state_lock);
3040
3041 if (flag || nilfs_segctor_confirm(sci))
3042 nilfs_segctor_write_out(sci);
3043
1f5abe7e 3044 WARN_ON(!list_empty(&sci->sc_copied_buffers));
9ff05123
RK		 3045
3046 if (!list_empty(&sci->sc_dirty_files)) {
3047 nilfs_warning(sbi->s_super, __func__,
3048 "dirty file(s) after the final construction\n");
3049 nilfs_dispose_list(sbi, &sci->sc_dirty_files, 1);
3050 }
3051 if (!list_empty(&sci->sc_active_segments))
3052 nilfs_dispose_segment_list(&sci->sc_active_segments);
3053
3054 if (!list_empty(&sci->sc_cleaning_segments))
3055 nilfs_dispose_segment_list(&sci->sc_cleaning_segments);
3056
1f5abe7e 3057 WARN_ON(!list_empty(&sci->sc_segbufs));
9ff05123 3058
9ff05123
RK		 3059 down_write(&sbi->s_nilfs->ns_segctor_sem);
3060
3061 kfree(sci);
3062}
3063
3064/**
3065 * nilfs_attach_segment_constructor - attach a segment constructor
3066 * @sbi: nilfs_sb_info
3067 * @ri: nilfs_recovery_info
3068 *
3069 * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info,
3070 * initilizes it, and starts the segment constructor.
3071 *
3072 * Return Value: On success, 0 is returned. On error, one of the following
3073 * negative error code is returned.
3074 *
3075 * %-ENOMEM - Insufficient memory available.
3076 */
3077int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi,
3078 struct nilfs_recovery_info *ri)
3079{
3080 struct the_nilfs *nilfs = sbi->s_nilfs;
3081 int err;
3082
3083 /* Each field of nilfs_segctor is cleared through the initialization
3084 of super-block info */
3085 sbi->s_sc_info = nilfs_segctor_new(sbi);
3086 if (!sbi->s_sc_info)
3087 return -ENOMEM;
3088
3089 nilfs_attach_writer(nilfs, sbi);
3090 err = nilfs_segctor_init(NILFS_SC(sbi), ri);
3091 if (err) {
3092 nilfs_detach_writer(nilfs, sbi);
3093 kfree(sbi->s_sc_info);
3094 sbi->s_sc_info = NULL;
3095 }
3096 return err;
3097}
3098
3099/**
3100 * nilfs_detach_segment_constructor - destroy the segment constructor
3101 * @sbi: nilfs_sb_info
3102 *
3103 * nilfs_detach_segment_constructor() kills the segment constructor daemon,
3104 * frees the struct nilfs_sc_info, and destroy the dirty file list.
3105 */
3106void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi)
3107{
3108 struct the_nilfs *nilfs = sbi->s_nilfs;
3109 LIST_HEAD(garbage_list);
3110
3111 down_write(&nilfs->ns_segctor_sem);
3112 if (NILFS_SC(sbi)) {
3113 nilfs_segctor_destroy(NILFS_SC(sbi));
3114 sbi->s_sc_info = NULL;
3115 }
3116
3117 /* Force to free the list of dirty files */
3118 spin_lock(&sbi->s_inode_lock);
3119 if (!list_empty(&sbi->s_dirty_files)) {
3120 list_splice_init(&sbi->s_dirty_files, &garbage_list);
3121 nilfs_warning(sbi->s_super, __func__,
3122 "Non empty dirty list after the last "
3123 "segment construction\n");
3124 }
3125 spin_unlock(&sbi->s_inode_lock);
3126 up_write(&nilfs->ns_segctor_sem);
3127
3128 nilfs_dispose_list(sbi, &garbage_list, 1);
3129 nilfs_detach_writer(nilfs, sbi);
3130}
Linux kernel - Deliverables
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