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nilfs2: move routine marking segment usage dirty into sufile
[linux-2.6-block.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"
9ff05123
RK		 42#include "segbuf.h"
43
44
45/*
46 * Segment constructor
47 */
48#define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
49
50#define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments
51 appended in collection retry loop */
52
53/* Construction mode */
54enum {
55 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
56 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make
57 a logical segment without a super root */
58 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without
59 creating a checkpoint */
60 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without
61 a checkpoint */
62};
63
64/* Stage numbers of dirty block collection */
65enum {
66 NILFS_ST_INIT = 0,
67 NILFS_ST_GC, /* Collecting dirty blocks for GC */
68 NILFS_ST_FILE,
9ff05123
RK		 69 NILFS_ST_IFILE,
70 NILFS_ST_CPFILE,
71 NILFS_ST_SUFILE,
72 NILFS_ST_DAT,
73 NILFS_ST_SR, /* Super root */
74 NILFS_ST_DSYNC, /* Data sync blocks */
75 NILFS_ST_DONE,
76};
77
78/* State flags of collection */
79#define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
80#define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
071cb4b8
RK		 81#define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
82#define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
9ff05123
RK		 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) &&
071cb4b8 813 sci->sc_nfreesegs == 0 &&
9ff05123
RK		 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
3961f0e2
RK		 977 nilfs_write_inode_common(nilfs_dat_inode(nilfs), (void *)raw_sr +
978 NILFS_SR_DAT_OFFSET(isz), 1);
979 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
980 NILFS_SR_CPFILE_OFFSET(isz), 1);
981 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
982 NILFS_SR_SUFILE_OFFSET(isz), 1);
9ff05123
RK		 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
9ff05123
RK		 1008static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1009 struct inode *inode,
1010 struct list_head *listp,
1011 int (*collect)(struct nilfs_sc_info *,
1012 struct buffer_head *,
1013 struct inode *))
1014{
1015 struct buffer_head *bh, *n;
1016 int err = 0;
1017
1018 if (collect) {
1019 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1020 list_del_init(&bh->b_assoc_buffers);
1021 err = collect(sci, bh, inode);
1022 brelse(bh);
1023 if (unlikely(err))
1024 goto dispose_buffers;
1025 }
1026 return 0;
1027 }
1028
1029 dispose_buffers:
1030 while (!list_empty(listp)) {
1031 bh = list_entry(listp->next, struct buffer_head,
1032 b_assoc_buffers);
1033 list_del_init(&bh->b_assoc_buffers);
1034 brelse(bh);
1035 }
1036 return err;
1037}
1038
f30bf3e4
RK		 1039static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1040{
1041 /* Remaining number of blocks within segment buffer */
1042 return sci->sc_segbuf_nblocks -
1043 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1044}
1045
9ff05123
RK		 1046static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1047 struct inode *inode,
1048 struct nilfs_sc_operations *sc_ops)
1049{
1050 LIST_HEAD(data_buffers);
1051 LIST_HEAD(node_buffers);
f30bf3e4 1052 int err;
9ff05123
RK		 1053
1054 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
f30bf3e4
RK		 1055 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1056
1057 n = nilfs_lookup_dirty_data_buffers(
1058 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1059 if (n > rest) {
1060 err = nilfs_segctor_apply_buffers(
9ff05123 1061 sci, inode, &data_buffers,
f30bf3e4
RK		 1062 sc_ops->collect_data);
1063 BUG_ON(!err); /* always receive -E2BIG or true error */
9ff05123
RK		 1064 goto break_or_fail;
1065 }
1066 }
1067 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1068
1069 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1070 err = nilfs_segctor_apply_buffers(
1071 sci, inode, &data_buffers, sc_ops->collect_data);
1072 if (unlikely(err)) {
1073 /* dispose node list */
1074 nilfs_segctor_apply_buffers(
1075 sci, inode, &node_buffers, NULL);
1076 goto break_or_fail;
1077 }
1078 sci->sc_stage.flags |= NILFS_CF_NODE;
1079 }
1080 /* Collect node */
1081 err = nilfs_segctor_apply_buffers(
1082 sci, inode, &node_buffers, sc_ops->collect_node);
1083 if (unlikely(err))
1084 goto break_or_fail;
1085
1086 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1087 err = nilfs_segctor_apply_buffers(
1088 sci, inode, &node_buffers, sc_ops->collect_bmap);
1089 if (unlikely(err))
1090 goto break_or_fail;
1091
1092 nilfs_segctor_end_finfo(sci, inode);
1093 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1094
1095 break_or_fail:
1096 return err;
1097}
1098
1099static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1100 struct inode *inode)
1101{
1102 LIST_HEAD(data_buffers);
f30bf3e4
RK		 1103 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1104 int err;
9ff05123 1105
f30bf3e4
RK		 1106 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1107 sci->sc_dsync_start,
1108 sci->sc_dsync_end);
1109
1110 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1111 nilfs_collect_file_data);
1112 if (!err) {
9ff05123 1113 nilfs_segctor_end_finfo(sci, inode);
f30bf3e4
RK		 1114 BUG_ON(n > rest);
1115 /* always receive -E2BIG or true error if n > rest */
1116 }
9ff05123
RK		 1117 return err;
1118}
1119
1120static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1121{
1122 struct nilfs_sb_info *sbi = sci->sc_sbi;
1123 struct the_nilfs *nilfs = sbi->s_nilfs;
1124 struct list_head *head;
1125 struct nilfs_inode_info *ii;
071cb4b8 1126 size_t ndone;
9ff05123
RK		 1127 int err = 0;
1128
1129 switch (sci->sc_stage.scnt) {
1130 case NILFS_ST_INIT:
1131 /* Pre-processes */
1132 sci->sc_stage.flags = 0;
1133
1134 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1135 sci->sc_nblk_inc = 0;
1136 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1137 if (mode == SC_LSEG_DSYNC) {
1138 sci->sc_stage.scnt = NILFS_ST_DSYNC;
1139 goto dsync_mode;
1140 }
1141 }
1142
1143 sci->sc_stage.dirty_file_ptr = NULL;
1144 sci->sc_stage.gc_inode_ptr = NULL;
1145 if (mode == SC_FLUSH_DAT) {
1146 sci->sc_stage.scnt = NILFS_ST_DAT;
1147 goto dat_stage;
1148 }
1149 sci->sc_stage.scnt++; /* Fall through */
1150 case NILFS_ST_GC:
1151 if (nilfs_doing_gc()) {
1152 head = &sci->sc_gc_inodes;
1153 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1154 head, i_dirty);
1155 list_for_each_entry_continue(ii, head, i_dirty) {
1156 err = nilfs_segctor_scan_file(
1157 sci, &ii->vfs_inode,
1158 &nilfs_sc_file_ops);
1159 if (unlikely(err)) {
1160 sci->sc_stage.gc_inode_ptr = list_entry(
1161 ii->i_dirty.prev,
1162 struct nilfs_inode_info,
1163 i_dirty);
1164 goto break_or_fail;
1165 }
1166 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1167 }
1168 sci->sc_stage.gc_inode_ptr = NULL;
1169 }
1170 sci->sc_stage.scnt++; /* Fall through */
1171 case NILFS_ST_FILE:
1172 head = &sci->sc_dirty_files;
1173 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1174 i_dirty);
1175 list_for_each_entry_continue(ii, head, i_dirty) {
1176 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1177
1178 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1179 &nilfs_sc_file_ops);
1180 if (unlikely(err)) {
1181 sci->sc_stage.dirty_file_ptr =
1182 list_entry(ii->i_dirty.prev,
1183 struct nilfs_inode_info,
1184 i_dirty);
1185 goto break_or_fail;
1186 }
1187 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1188 /* XXX: required ? */
1189 }
1190 sci->sc_stage.dirty_file_ptr = NULL;
1191 if (mode == SC_FLUSH_FILE) {
1192 sci->sc_stage.scnt = NILFS_ST_DONE;
1193 return 0;
1194 }
9ff05123
RK		 1195 sci->sc_stage.scnt++;
1196 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1197 /* Fall through */
1198 case NILFS_ST_IFILE:
1199 err = nilfs_segctor_scan_file(sci, sbi->s_ifile,
1200 &nilfs_sc_file_ops);
1201 if (unlikely(err))
1202 break;
1203 sci->sc_stage.scnt++;
1204 /* Creating a checkpoint */
1205 err = nilfs_segctor_create_checkpoint(sci);
1206 if (unlikely(err))
1207 break;
1208 /* Fall through */
1209 case NILFS_ST_CPFILE:
1210 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1211 &nilfs_sc_file_ops);
1212 if (unlikely(err))
1213 break;
1214 sci->sc_stage.scnt++; /* Fall through */
1215 case NILFS_ST_SUFILE:
071cb4b8
RK		 1216 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1217 sci->sc_nfreesegs, &ndone);
1218 if (unlikely(err)) {
1219 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1220 sci->sc_freesegs, ndone,
1221 NULL);
9ff05123 1222 break;
071cb4b8
RK		 1223 }
1224 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1225
9ff05123
RK		 1226 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1227 &nilfs_sc_file_ops);
1228 if (unlikely(err))
1229 break;
1230 sci->sc_stage.scnt++; /* Fall through */
1231 case NILFS_ST_DAT:
1232 dat_stage:
1233 err = nilfs_segctor_scan_file(sci, nilfs_dat_inode(nilfs),
1234 &nilfs_sc_dat_ops);
1235 if (unlikely(err))
1236 break;
1237 if (mode == SC_FLUSH_DAT) {
1238 sci->sc_stage.scnt = NILFS_ST_DONE;
1239 return 0;
1240 }
1241 sci->sc_stage.scnt++; /* Fall through */
1242 case NILFS_ST_SR:
1243 if (mode == SC_LSEG_SR) {
1244 /* Appending a super root */
1245 err = nilfs_segctor_add_super_root(sci);
1246 if (unlikely(err))
1247 break;
1248 }
1249 /* End of a logical segment */
1250 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1251 sci->sc_stage.scnt = NILFS_ST_DONE;
1252 return 0;
1253 case NILFS_ST_DSYNC:
1254 dsync_mode:
1255 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
f30bf3e4 1256 ii = sci->sc_dsync_inode;
9ff05123
RK		 1257 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1258 break;
1259
1260 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1261 if (unlikely(err))
1262 break;
9ff05123
RK		 1263 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1264 sci->sc_stage.scnt = NILFS_ST_DONE;
1265 return 0;
1266 case NILFS_ST_DONE:
1267 return 0;
1268 default:
1269 BUG();
1270 }
1271
1272 break_or_fail:
1273 return err;
1274}
1275
9ff05123
RK		 1276static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1277 struct the_nilfs *nilfs)
1278{
1279 struct nilfs_segment_buffer *segbuf, *n;
9ff05123
RK		 1280 __u64 nextnum;
1281 int err;
1282
1283 if (list_empty(&sci->sc_segbufs)) {
1284 segbuf = nilfs_segbuf_new(sci->sc_super);
1285 if (unlikely(!segbuf))
1286 return -ENOMEM;
1287 list_add(&segbuf->sb_list, &sci->sc_segbufs);
1288 } else
1289 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1290
cece5520
RK		 1291 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, nilfs->ns_pseg_offset,
1292 nilfs);
9ff05123
RK		 1293
1294 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
9ff05123 1295 nilfs_shift_to_next_segment(nilfs);
cece5520 1296 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
9ff05123
RK		 1297 }
1298 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1299
61a189e9 1300 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
9ff05123
RK		 1301 if (unlikely(err))
1302 return err;
1303
1304 if (nilfs->ns_segnum == nilfs->ns_nextnum) {
1305 /* Start from the head of a new full segment */
cece5520 1306 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
9ff05123
RK		 1307 if (unlikely(err))
1308 return err;
1309 } else
1310 nextnum = nilfs->ns_nextnum;
1311
1312 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1313 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1314
1315 /* truncating segment buffers */
1316 list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs,
1317 sb_list) {
1318 list_del_init(&segbuf->sb_list);
1319 nilfs_segbuf_free(segbuf);
1320 }
cece5520 1321 return 0;
9ff05123
RK		 1322}
1323
1324static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1325 struct the_nilfs *nilfs, int nadd)
1326{
1327 struct nilfs_segment_buffer *segbuf, *prev, *n;
1328 struct inode *sufile = nilfs->ns_sufile;
1329 __u64 nextnextnum;
1330 LIST_HEAD(list);
1331 int err, ret, i;
1332
1333 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1334 /*
1335 * Since the segment specified with nextnum might be allocated during
1336 * the previous construction, the buffer including its segusage may
1337 * not be dirty. The following call ensures that the buffer is dirty
1338 * and will pin the buffer on memory until the sufile is written.
1339 */
61a189e9 1340 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
9ff05123
RK		 1341 if (unlikely(err))
1342 return err;
1343
1344 for (i = 0; i < nadd; i++) {
1345 /* extend segment info */
1346 err = -ENOMEM;
1347 segbuf = nilfs_segbuf_new(sci->sc_super);
1348 if (unlikely(!segbuf))
1349 goto failed;
1350
1351 /* map this buffer to region of segment on-disk */
cece5520 1352 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
9ff05123
RK		 1353 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1354
1355 /* allocate the next next full segment */
1356 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1357 if (unlikely(err))
1358 goto failed_segbuf;
1359
1360 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1361 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1362
1363 list_add_tail(&segbuf->sb_list, &list);
1364 prev = segbuf;
1365 }
1366 list_splice(&list, sci->sc_segbufs.prev);
1367 return 0;
1368
1369 failed_segbuf:
1370 nilfs_segbuf_free(segbuf);
1371 failed:
1372 list_for_each_entry_safe(segbuf, n, &list, sb_list) {
1373 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1374 WARN_ON(ret); /* never fails */
9ff05123
RK		 1375 list_del_init(&segbuf->sb_list);
1376 nilfs_segbuf_free(segbuf);
1377 }
1378 return err;
1379}
1380
1381static void nilfs_segctor_free_incomplete_segments(struct nilfs_sc_info *sci,
1382 struct the_nilfs *nilfs)
1383{
1384 struct nilfs_segment_buffer *segbuf;
1385 int ret, done = 0;
1386
1387 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1388 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1389 ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum);
1f5abe7e 1390 WARN_ON(ret); /* never fails */
9ff05123
RK		 1391 }
1392 if (segbuf->sb_io_error) {
1393 /* Case 1: The first segment failed */
1394 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1395 /* Case 1a: Partial segment appended into an existing
1396 segment */
1397 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1398 segbuf->sb_fseg_end);
1399 else /* Case 1b: New full segment */
1400 set_nilfs_discontinued(nilfs);
1401 done++;
1402 }
1403
1404 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1405 ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum);
1f5abe7e 1406 WARN_ON(ret); /* never fails */
9ff05123
RK		 1407 if (!done && segbuf->sb_io_error) {
1408 if (segbuf->sb_segnum != nilfs->ns_nextnum)
1409 /* Case 2: extended segment (!= next) failed */
1410 nilfs_sufile_set_error(nilfs->ns_sufile,
1411 segbuf->sb_segnum);
1412 done++;
1413 }
1414 }
1415}
1416
1417static void nilfs_segctor_clear_segment_buffers(struct nilfs_sc_info *sci)
1418{
1419 struct nilfs_segment_buffer *segbuf;
1420
1421 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list)
1422 nilfs_segbuf_clear(segbuf);
1423 sci->sc_super_root = NULL;
1424}
1425
1426static void nilfs_segctor_destroy_segment_buffers(struct nilfs_sc_info *sci)
1427{
1428 struct nilfs_segment_buffer *segbuf;
1429
1430 while (!list_empty(&sci->sc_segbufs)) {
1431 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1432 list_del_init(&segbuf->sb_list);
1433 nilfs_segbuf_free(segbuf);
1434 }
1435 /* sci->sc_curseg = NULL; */
1436}
1437
1438static void nilfs_segctor_end_construction(struct nilfs_sc_info *sci,
1439 struct the_nilfs *nilfs, int err)
1440{
1441 if (unlikely(err)) {
1442 nilfs_segctor_free_incomplete_segments(sci, nilfs);
071cb4b8
RK		 1443 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1444 int ret;
1445
1446 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1447 sci->sc_freesegs,
1448 sci->sc_nfreesegs,
1449 NULL);
1450 WARN_ON(ret); /* do not happen */
1451 }
9ff05123
RK		 1452 }
1453 nilfs_segctor_clear_segment_buffers(sci);
1454}
1455
1456static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1457 struct inode *sufile)
1458{
1459 struct nilfs_segment_buffer *segbuf;
1460 struct buffer_head *bh_su;
1461 struct nilfs_segment_usage *raw_su;
1462 unsigned long live_blocks;
1463 int ret;
1464
1465 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1466 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum,
1467 &raw_su, &bh_su);
1f5abe7e 1468 WARN_ON(ret); /* always succeed because bh_su is dirty */
9ff05123
RK		 1469 live_blocks = segbuf->sb_sum.nblocks +
1470 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1471 raw_su->su_lastmod = cpu_to_le64(sci->sc_seg_ctime);
1472 raw_su->su_nblocks = cpu_to_le32(live_blocks);
1473 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum,
1474 bh_su);
1475 }
1476}
1477
1478static void nilfs_segctor_cancel_segusage(struct nilfs_sc_info *sci,
1479 struct inode *sufile)
1480{
1481 struct nilfs_segment_buffer *segbuf;
1482 struct buffer_head *bh_su;
1483 struct nilfs_segment_usage *raw_su;
1484 int ret;
1485
1486 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1487 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum,
1488 &raw_su, &bh_su);
1f5abe7e 1489 WARN_ON(ret); /* always succeed because bh_su is dirty */
9ff05123
RK		 1490 raw_su->su_nblocks = cpu_to_le32(segbuf->sb_pseg_start -
1491 segbuf->sb_fseg_start);
1492 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, bh_su);
1493
1494 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1495 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum,
1496 &raw_su, &bh_su);
1f5abe7e 1497 WARN_ON(ret); /* always succeed */
9ff05123
RK		 1498 raw_su->su_nblocks = 0;
1499 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum,
1500 bh_su);
1501 }
1502}
1503
1504static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1505 struct nilfs_segment_buffer *last,
1506 struct inode *sufile)
1507{
1508 struct nilfs_segment_buffer *segbuf = last, *n;
1509 int ret;
1510
1511 list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs,
1512 sb_list) {
1513 list_del_init(&segbuf->sb_list);
1514 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1515 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1516 WARN_ON(ret);
9ff05123
RK		 1517 nilfs_segbuf_free(segbuf);
1518 }
1519}
1520
1521
1522static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1523 struct the_nilfs *nilfs, int mode)
1524{
1525 struct nilfs_cstage prev_stage = sci->sc_stage;
1526 int err, nadd = 1;
1527
1528 /* Collection retry loop */
1529 for (;;) {
1530 sci->sc_super_root = NULL;
1531 sci->sc_nblk_this_inc = 0;
1532 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1533
1534 err = nilfs_segctor_reset_segment_buffer(sci);
1535 if (unlikely(err))
1536 goto failed;
1537
1538 err = nilfs_segctor_collect_blocks(sci, mode);
1539 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1540 if (!err)
1541 break;
1542
1543 if (unlikely(err != -E2BIG))
1544 goto failed;
1545
1546 /* The current segment is filled up */
1547 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE)
1548 break;
1549
071cb4b8
RK		 1550 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1551 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1552 sci->sc_freesegs,
1553 sci->sc_nfreesegs,
1554 NULL);
1555 WARN_ON(err); /* do not happen */
1556 }
9ff05123
RK		 1557 nilfs_segctor_clear_segment_buffers(sci);
1558
1559 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1560 if (unlikely(err))
1561 return err;
1562
1563 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1564 sci->sc_stage = prev_stage;
1565 }
1566 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1567 return 0;
1568
1569 failed:
1570 return err;
1571}
1572
1573static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1574 struct buffer_head *new_bh)
1575{
1576 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1577
1578 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1579 /* The caller must release old_bh */
1580}
1581
1582static int
1583nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1584 struct nilfs_segment_buffer *segbuf,
1585 int mode)
1586{
1587 struct inode *inode = NULL;
1588 sector_t blocknr;
1589 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1590 unsigned long nblocks = 0, ndatablk = 0;
1591 struct nilfs_sc_operations *sc_op = NULL;
1592 struct nilfs_segsum_pointer ssp;
1593 struct nilfs_finfo *finfo = NULL;
1594 union nilfs_binfo binfo;
1595 struct buffer_head *bh, *bh_org;
1596 ino_t ino = 0;
1597 int err = 0;
1598
1599 if (!nfinfo)
1600 goto out;
1601
1602 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1603 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1604 ssp.offset = sizeof(struct nilfs_segment_summary);
1605
1606 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1607 if (bh == sci->sc_super_root)
1608 break;
1609 if (!finfo) {
1610 finfo = nilfs_segctor_map_segsum_entry(
1611 sci, &ssp, sizeof(*finfo));
1612 ino = le64_to_cpu(finfo->fi_ino);
1613 nblocks = le32_to_cpu(finfo->fi_nblocks);
1614 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1615
1616 if (buffer_nilfs_node(bh))
1617 inode = NILFS_BTNC_I(bh->b_page->mapping);
1618 else
1619 inode = NILFS_AS_I(bh->b_page->mapping);
1620
1621 if (mode == SC_LSEG_DSYNC)
1622 sc_op = &nilfs_sc_dsync_ops;
1623 else if (ino == NILFS_DAT_INO)
1624 sc_op = &nilfs_sc_dat_ops;
1625 else /* file blocks */
1626 sc_op = &nilfs_sc_file_ops;
1627 }
1628 bh_org = bh;
1629 get_bh(bh_org);
1630 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1631 &binfo);
1632 if (bh != bh_org)
1633 nilfs_list_replace_buffer(bh_org, bh);
1634 brelse(bh_org);
1635 if (unlikely(err))
1636 goto failed_bmap;
1637
1638 if (ndatablk > 0)
1639 sc_op->write_data_binfo(sci, &ssp, &binfo);
1640 else
1641 sc_op->write_node_binfo(sci, &ssp, &binfo);
1642
1643 blocknr++;
1644 if (--nblocks == 0) {
1645 finfo = NULL;
1646 if (--nfinfo == 0)
1647 break;
1648 } else if (ndatablk > 0)
1649 ndatablk--;
1650 }
1651 out:
1652 return 0;
1653
1654 failed_bmap:
1655 err = nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super);
1656 return err;
1657}
1658
1659static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1660{
1661 struct nilfs_segment_buffer *segbuf;
1662 int err;
1663
1664 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1665 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1666 if (unlikely(err))
1667 return err;
1668 nilfs_segbuf_fill_in_segsum(segbuf);
1669 }
1670 return 0;
1671}
1672
1673static int
1674nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out)
1675{
1676 struct page *clone_page;
1677 struct buffer_head *bh, *head, *bh2;
1678 void *kaddr;
1679
1680 bh = head = page_buffers(page);
1681
1682 clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0);
1683 if (unlikely(!clone_page))
1684 return -ENOMEM;
1685
1686 bh2 = page_buffers(clone_page);
1687 kaddr = kmap_atomic(page, KM_USER0);
1688 do {
1689 if (list_empty(&bh->b_assoc_buffers))
1690 continue;
1691 get_bh(bh2);
1692 page_cache_get(clone_page); /* for each bh */
1693 memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size);
1694 bh2->b_blocknr = bh->b_blocknr;
1695 list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers);
1696 list_add_tail(&bh->b_assoc_buffers, out);
1697 } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head);
1698 kunmap_atomic(kaddr, KM_USER0);
1699
1700 if (!TestSetPageWriteback(clone_page))
1701 inc_zone_page_state(clone_page, NR_WRITEBACK);
1702 unlock_page(clone_page);
1703
1704 return 0;
1705}
1706
1707static int nilfs_test_page_to_be_frozen(struct page *page)
1708{
1709 struct address_space *mapping = page->mapping;
1710
1711 if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode))
1712 return 0;
1713
1714 if (page_mapped(page)) {
1715 ClearPageChecked(page);
1716 return 1;
1717 }
1718 return PageChecked(page);
1719}
1720
1721static int nilfs_begin_page_io(struct page *page, struct list_head *out)
1722{
1723 if (!page || PageWriteback(page))
1724 /* For split b-tree node pages, this function may be called
1725 twice. We ignore the 2nd or later calls by this check. */
1726 return 0;
1727
1728 lock_page(page);
1729 clear_page_dirty_for_io(page);
1730 set_page_writeback(page);
1731 unlock_page(page);
1732
1733 if (nilfs_test_page_to_be_frozen(page)) {
1734 int err = nilfs_copy_replace_page_buffers(page, out);
1735 if (unlikely(err))
1736 return err;
1737 }
1738 return 0;
1739}
1740
1741static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci,
1742 struct page **failed_page)
1743{
1744 struct nilfs_segment_buffer *segbuf;
1745 struct page *bd_page = NULL, *fs_page = NULL;
1746 struct list_head *list = &sci->sc_copied_buffers;
1747 int err;
1748
1749 *failed_page = NULL;
1750 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1751 struct buffer_head *bh;
1752
1753 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1754 b_assoc_buffers) {
1755 if (bh->b_page != bd_page) {
1756 if (bd_page) {
1757 lock_page(bd_page);
1758 clear_page_dirty_for_io(bd_page);
1759 set_page_writeback(bd_page);
1760 unlock_page(bd_page);
1761 }
1762 bd_page = bh->b_page;
1763 }
1764 }
1765
1766 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1767 b_assoc_buffers) {
1768 if (bh == sci->sc_super_root) {
1769 if (bh->b_page != bd_page) {
1770 lock_page(bd_page);
1771 clear_page_dirty_for_io(bd_page);
1772 set_page_writeback(bd_page);
1773 unlock_page(bd_page);
1774 bd_page = bh->b_page;
1775 }
1776 break;
1777 }
1778 if (bh->b_page != fs_page) {
1779 err = nilfs_begin_page_io(fs_page, list);
1780 if (unlikely(err)) {
1781 *failed_page = fs_page;
1782 goto out;
1783 }
1784 fs_page = bh->b_page;
1785 }
1786 }
1787 }
1788 if (bd_page) {
1789 lock_page(bd_page);
1790 clear_page_dirty_for_io(bd_page);
1791 set_page_writeback(bd_page);
1792 unlock_page(bd_page);
1793 }
1794 err = nilfs_begin_page_io(fs_page, list);
1795 if (unlikely(err))
1796 *failed_page = fs_page;
1797 out:
1798 return err;
1799}
1800
1801static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1802 struct backing_dev_info *bdi)
1803{
1804 struct nilfs_segment_buffer *segbuf;
1805 struct nilfs_write_info wi;
1806 int err, res;
1807
1808 wi.sb = sci->sc_super;
1809 wi.bh_sr = sci->sc_super_root;
1810 wi.bdi = bdi;
1811
1812 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1813 nilfs_segbuf_prepare_write(segbuf, &wi);
1814 err = nilfs_segbuf_write(segbuf, &wi);
1815
1816 res = nilfs_segbuf_wait(segbuf, &wi);
0cfae3d8
RK		 1817 err = err ? : res;
1818 if (err)
9ff05123
RK		 1819 return err;
1820 }
1821 return 0;
1822}
1823
9ff05123
RK		 1824static void __nilfs_end_page_io(struct page *page, int err)
1825{
9ff05123
RK		 1826 if (!err) {
1827 if (!nilfs_page_buffers_clean(page))
1828 __set_page_dirty_nobuffers(page);
1829 ClearPageError(page);
1830 } else {
1831 __set_page_dirty_nobuffers(page);
1832 SetPageError(page);
1833 }
1834
1835 if (buffer_nilfs_allocated(page_buffers(page))) {
1836 if (TestClearPageWriteback(page))
1837 dec_zone_page_state(page, NR_WRITEBACK);
1838 } else
1839 end_page_writeback(page);
1840}
1841
1842static void nilfs_end_page_io(struct page *page, int err)
1843{
1844 if (!page)
1845 return;
1846
a9777845 1847 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
8227b297
RK		 1848 /*
1849 * For b-tree node pages, this function may be called twice
1850 * or more because they might be split in a segment.
1851 */
a9777845
RK		 1852 if (PageDirty(page)) {
1853 /*
1854 * For pages holding split b-tree node buffers, dirty
1855 * flag on the buffers may be cleared discretely.
1856 * In that case, the page is once redirtied for
1857 * remaining buffers, and it must be cancelled if
1858 * all the buffers get cleaned later.
1859 */
1860 lock_page(page);
1861 if (nilfs_page_buffers_clean(page))
1862 __nilfs_clear_page_dirty(page);
1863 unlock_page(page);
1864 }
9ff05123 1865 return;
a9777845 1866 }
9ff05123
RK		 1867
1868 __nilfs_end_page_io(page, err);
1869}
1870
1871static void nilfs_clear_copied_buffers(struct list_head *list, int err)
1872{
1873 struct buffer_head *bh, *head;
1874 struct page *page;
1875
1876 while (!list_empty(list)) {
1877 bh = list_entry(list->next, struct buffer_head,
1878 b_assoc_buffers);
1879 page = bh->b_page;
1880 page_cache_get(page);
1881 head = bh = page_buffers(page);
1882 do {
1883 if (!list_empty(&bh->b_assoc_buffers)) {
1884 list_del_init(&bh->b_assoc_buffers);
1885 if (!err) {
1886 set_buffer_uptodate(bh);
1887 clear_buffer_dirty(bh);
1888 clear_buffer_nilfs_volatile(bh);
1889 }
1890 brelse(bh); /* for b_assoc_buffers */
1891 }
1892 } while ((bh = bh->b_this_page) != head);
1893
1894 __nilfs_end_page_io(page, err);
1895 page_cache_release(page);
1896 }
1897}
1898
1899static void nilfs_segctor_abort_write(struct nilfs_sc_info *sci,
1900 struct page *failed_page, int err)
1901{
1902 struct nilfs_segment_buffer *segbuf;
1903 struct page *bd_page = NULL, *fs_page = NULL;
1904
1905 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1906 struct buffer_head *bh;
1907
1908 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1909 b_assoc_buffers) {
1910 if (bh->b_page != bd_page) {
1911 if (bd_page)
1912 end_page_writeback(bd_page);
1913 bd_page = bh->b_page;
1914 }
1915 }
1916
1917 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1918 b_assoc_buffers) {
1919 if (bh == sci->sc_super_root) {
1920 if (bh->b_page != bd_page) {
1921 end_page_writeback(bd_page);
1922 bd_page = bh->b_page;
1923 }
1924 break;
1925 }
1926 if (bh->b_page != fs_page) {
1927 nilfs_end_page_io(fs_page, err);
8227b297 1928 if (fs_page && fs_page == failed_page)
9ff05123
RK		 1929 goto done;
1930 fs_page = bh->b_page;
1931 }
1932 }
1933 }
1934 if (bd_page)
1935 end_page_writeback(bd_page);
1936
1937 nilfs_end_page_io(fs_page, err);
1938 done:
1939 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err);
1940}
1941
1942static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1943 struct nilfs_segment_buffer *segbuf)
1944{
1945 nilfs->ns_segnum = segbuf->sb_segnum;
1946 nilfs->ns_nextnum = segbuf->sb_nextnum;
1947 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1948 + segbuf->sb_sum.nblocks;
1949 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1950 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1951}
1952
1953static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1954{
1955 struct nilfs_segment_buffer *segbuf;
1956 struct page *bd_page = NULL, *fs_page = NULL;
1957 struct nilfs_sb_info *sbi = sci->sc_sbi;
1958 struct the_nilfs *nilfs = sbi->s_nilfs;
1959 int update_sr = (sci->sc_super_root != NULL);
1960
1961 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1962 struct buffer_head *bh;
1963
1964 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1965 b_assoc_buffers) {
1966 set_buffer_uptodate(bh);
1967 clear_buffer_dirty(bh);
1968 if (bh->b_page != bd_page) {
1969 if (bd_page)
1970 end_page_writeback(bd_page);
1971 bd_page = bh->b_page;
1972 }
1973 }
1974 /*
1975 * We assume that the buffers which belong to the same page
1976 * continue over the buffer list.
1977 * Under this assumption, the last BHs of pages is
1978 * identifiable by the discontinuity of bh->b_page
1979 * (page != fs_page).
1980 *
1981 * For B-tree node blocks, however, this assumption is not
1982 * guaranteed. The cleanup code of B-tree node pages needs
1983 * special care.
1984 */
1985 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1986 b_assoc_buffers) {
1987 set_buffer_uptodate(bh);
1988 clear_buffer_dirty(bh);
1989 clear_buffer_nilfs_volatile(bh);
1990 if (bh == sci->sc_super_root) {
1991 if (bh->b_page != bd_page) {
1992 end_page_writeback(bd_page);
1993 bd_page = bh->b_page;
1994 }
1995 break;
1996 }
1997 if (bh->b_page != fs_page) {
1998 nilfs_end_page_io(fs_page, 0);
1999 fs_page = bh->b_page;
2000 }
2001 }
2002
2003 if (!NILFS_SEG_SIMPLEX(&segbuf->sb_sum)) {
2004 if (NILFS_SEG_LOGBGN(&segbuf->sb_sum)) {
2005 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
2006 sci->sc_lseg_stime = jiffies;
2007 }
2008 if (NILFS_SEG_LOGEND(&segbuf->sb_sum))
2009 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
2010 }
2011 }
2012 /*
2013 * Since pages may continue over multiple segment buffers,
2014 * end of the last page must be checked outside of the loop.
2015 */
2016 if (bd_page)
2017 end_page_writeback(bd_page);
2018
2019 nilfs_end_page_io(fs_page, 0);
2020
2021 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0);
2022
2023 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
2024
2025 if (nilfs_doing_gc()) {
2026 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
2027 if (update_sr)
2028 nilfs_commit_gcdat_inode(nilfs);
1088dcf4 2029 } else
9ff05123 2030 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
9ff05123
RK		 2031
2032 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
2033
2034 segbuf = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
2035 nilfs_set_next_segment(nilfs, segbuf);
2036
2037 if (update_sr) {
2038 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
e339ad31
RK		 2039 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
2040 sbi->s_super->s_dirt = 1;
9ff05123 2041
c96fa464 2042 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
9ff05123
RK		 2043 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2044 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
2045 } else
2046 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
2047}
2048
2049static int nilfs_segctor_check_in_files(struct nilfs_sc_info *sci,
2050 struct nilfs_sb_info *sbi)
2051{
2052 struct nilfs_inode_info *ii, *n;
2053 __u64 cno = sbi->s_nilfs->ns_cno;
2054
2055 spin_lock(&sbi->s_inode_lock);
2056 retry:
2057 list_for_each_entry_safe(ii, n, &sbi->s_dirty_files, i_dirty) {
2058 if (!ii->i_bh) {
2059 struct buffer_head *ibh;
2060 int err;
2061
2062 spin_unlock(&sbi->s_inode_lock);
2063 err = nilfs_ifile_get_inode_block(
2064 sbi->s_ifile, ii->vfs_inode.i_ino, &ibh);
2065 if (unlikely(err)) {
2066 nilfs_warning(sbi->s_super, __func__,
2067 "failed to get inode block.\n");
2068 return err;
2069 }
2070 nilfs_mdt_mark_buffer_dirty(ibh);
2071 nilfs_mdt_mark_dirty(sbi->s_ifile);
2072 spin_lock(&sbi->s_inode_lock);
2073 if (likely(!ii->i_bh))
2074 ii->i_bh = ibh;
2075 else
2076 brelse(ibh);
2077 goto retry;
2078 }
2079 ii->i_cno = cno;
2080
2081 clear_bit(NILFS_I_QUEUED, &ii->i_state);
2082 set_bit(NILFS_I_BUSY, &ii->i_state);
2083 list_del(&ii->i_dirty);
2084 list_add_tail(&ii->i_dirty, &sci->sc_dirty_files);
2085 }
2086 spin_unlock(&sbi->s_inode_lock);
2087
2088 NILFS_I(sbi->s_ifile)->i_cno = cno;
2089
2090 return 0;
2091}
2092
2093static void nilfs_segctor_check_out_files(struct nilfs_sc_info *sci,
2094 struct nilfs_sb_info *sbi)
2095{
2096 struct nilfs_transaction_info *ti = current->journal_info;
2097 struct nilfs_inode_info *ii, *n;
2098 __u64 cno = sbi->s_nilfs->ns_cno;
2099
2100 spin_lock(&sbi->s_inode_lock);
2101 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2102 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
2103 test_bit(NILFS_I_DIRTY, &ii->i_state)) {
2104 /* The current checkpoint number (=nilfs->ns_cno) is
2105 changed between check-in and check-out only if the
2106 super root is written out. So, we can update i_cno
2107 for the inodes that remain in the dirty list. */
2108 ii->i_cno = cno;
2109 continue;
2110 }
2111 clear_bit(NILFS_I_BUSY, &ii->i_state);
2112 brelse(ii->i_bh);
2113 ii->i_bh = NULL;
2114 list_del(&ii->i_dirty);
2115 list_add_tail(&ii->i_dirty, &ti->ti_garbage);
2116 }
2117 spin_unlock(&sbi->s_inode_lock);
2118}
2119
9ff05123
RK		 2120/*
2121 * Main procedure of segment constructor
2122 */
2123static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2124{
2125 struct nilfs_sb_info *sbi = sci->sc_sbi;
2126 struct the_nilfs *nilfs = sbi->s_nilfs;
2127 struct page *failed_page;
2128 int err, has_sr = 0;
2129
2130 sci->sc_stage.scnt = NILFS_ST_INIT;
2131
2132 err = nilfs_segctor_check_in_files(sci, sbi);
2133 if (unlikely(err))
2134 goto out;
2135
2136 if (nilfs_test_metadata_dirty(sbi))
2137 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2138
2139 if (nilfs_segctor_clean(sci))
2140 goto out;
2141
2142 do {
2143 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2144
2145 err = nilfs_segctor_begin_construction(sci, nilfs);
2146 if (unlikely(err))
2147 goto out;
2148
2149 /* Update time stamp */
2150 sci->sc_seg_ctime = get_seconds();
2151
2152 err = nilfs_segctor_collect(sci, nilfs, mode);
2153 if (unlikely(err))
2154 goto failed;
2155
2156 has_sr = (sci->sc_super_root != NULL);
2157
2158 /* Avoid empty segment */
2159 if (sci->sc_stage.scnt == NILFS_ST_DONE &&
2160 NILFS_SEG_EMPTY(&sci->sc_curseg->sb_sum)) {
9ff05123
RK		 2161 nilfs_segctor_end_construction(sci, nilfs, 1);
2162 goto out;
2163 }
2164
2165 err = nilfs_segctor_assign(sci, mode);
2166 if (unlikely(err))
2167 goto failed;
2168
9ff05123
RK		 2169 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2170 nilfs_segctor_fill_in_file_bmap(sci, sbi->s_ifile);
2171
2172 if (has_sr) {
2173 err = nilfs_segctor_fill_in_checkpoint(sci);
2174 if (unlikely(err))
2175 goto failed_to_make_up;
2176
2177 nilfs_segctor_fill_in_super_root(sci, nilfs);
2178 }
2179 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2180
2181 /* Write partial segments */
2182 err = nilfs_segctor_prepare_write(sci, &failed_page);
2183 if (unlikely(err))
2184 goto failed_to_write;
2185
2186 nilfs_segctor_fill_in_checksums(sci, nilfs->ns_crc_seed);
2187
2188 err = nilfs_segctor_write(sci, nilfs->ns_bdi);
2189 if (unlikely(err))
2190 goto failed_to_write;
2191
2192 nilfs_segctor_complete_write(sci);
2193
2194 /* Commit segments */
071cb4b8 2195 if (has_sr)
9ff05123 2196 nilfs_segctor_clear_metadata_dirty(sci);
9ff05123
RK		 2197
2198 nilfs_segctor_end_construction(sci, nilfs, 0);
2199
2200 } while (sci->sc_stage.scnt != NILFS_ST_DONE);
2201
9ff05123
RK		 2202 out:
2203 nilfs_segctor_destroy_segment_buffers(sci);
2204 nilfs_segctor_check_out_files(sci, sbi);
2205 return err;
2206
2207 failed_to_write:
2208 nilfs_segctor_abort_write(sci, failed_page, err);
2209 nilfs_segctor_cancel_segusage(sci, nilfs->ns_sufile);
2210
2211 failed_to_make_up:
2212 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2213 nilfs_redirty_inodes(&sci->sc_dirty_files);
9ff05123
RK		 2214
2215 failed:
2216 if (nilfs_doing_gc())
2217 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2218 nilfs_segctor_end_construction(sci, nilfs, err);
2219 goto out;
2220}
2221
2222/**
2223 * nilfs_secgtor_start_timer - set timer of background write
2224 * @sci: nilfs_sc_info
2225 *
2226 * If the timer has already been set, it ignores the new request.
2227 * This function MUST be called within a section locking the segment
2228 * semaphore.
2229 */
2230static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2231{
2232 spin_lock(&sci->sc_state_lock);
2233 if (sci->sc_timer && !(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2234 sci->sc_timer->expires = jiffies + sci->sc_interval;
2235 add_timer(sci->sc_timer);
2236 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2237 }
2238 spin_unlock(&sci->sc_state_lock);
2239}
2240
2241static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2242{
2243 spin_lock(&sci->sc_state_lock);
2244 if (!(sci->sc_flush_request & (1 << bn))) {
2245 unsigned long prev_req = sci->sc_flush_request;
2246
2247 sci->sc_flush_request |= (1 << bn);
2248 if (!prev_req)
2249 wake_up(&sci->sc_wait_daemon);
2250 }
2251 spin_unlock(&sci->sc_state_lock);
2252}
2253
2254/**
2255 * nilfs_flush_segment - trigger a segment construction for resource control
2256 * @sb: super block
2257 * @ino: inode number of the file to be flushed out.
2258 */
2259void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2260{
2261 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2262 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2263
2264 if (!sci || nilfs_doing_construction())
2265 return;
2266 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2267 /* assign bit 0 to data files */
2268}
2269
9ff05123
RK		 2270struct nilfs_segctor_wait_request {
2271 wait_queue_t wq;
2272 __u32 seq;
2273 int err;
2274 atomic_t done;
2275};
2276
2277static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2278{
2279 struct nilfs_segctor_wait_request wait_req;
2280 int err = 0;
2281
2282 spin_lock(&sci->sc_state_lock);
2283 init_wait(&wait_req.wq);
2284 wait_req.err = 0;
2285 atomic_set(&wait_req.done, 0);
2286 wait_req.seq = ++sci->sc_seq_request;
2287 spin_unlock(&sci->sc_state_lock);
2288
2289 init_waitqueue_entry(&wait_req.wq, current);
2290 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2291 set_current_state(TASK_INTERRUPTIBLE);
2292 wake_up(&sci->sc_wait_daemon);
2293
2294 for (;;) {
2295 if (atomic_read(&wait_req.done)) {
2296 err = wait_req.err;
2297 break;
2298 }
2299 if (!signal_pending(current)) {
2300 schedule();
2301 continue;
2302 }
2303 err = -ERESTARTSYS;
2304 break;
2305 }
2306 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2307 return err;
2308}
2309
2310static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2311{
2312 struct nilfs_segctor_wait_request *wrq, *n;
2313 unsigned long flags;
2314
2315 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2316 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2317 wq.task_list) {
2318 if (!atomic_read(&wrq->done) &&
2319 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2320 wrq->err = err;
2321 atomic_set(&wrq->done, 1);
2322 }
2323 if (atomic_read(&wrq->done)) {
2324 wrq->wq.func(&wrq->wq,
2325 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2326 0, NULL);
2327 }
2328 }
2329 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2330}
2331
2332/**
2333 * nilfs_construct_segment - construct a logical segment
2334 * @sb: super block
2335 *
2336 * Return Value: On success, 0 is retured. On errors, one of the following
2337 * negative error code is returned.
2338 *
2339 * %-EROFS - Read only filesystem.
2340 *
2341 * %-EIO - I/O error
2342 *
2343 * %-ENOSPC - No space left on device (only in a panic state).
2344 *
2345 * %-ERESTARTSYS - Interrupted.
2346 *
2347 * %-ENOMEM - Insufficient memory available.
2348 */
2349int nilfs_construct_segment(struct super_block *sb)
2350{
2351 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2352 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2353 struct nilfs_transaction_info *ti;
2354 int err;
2355
2356 if (!sci)
2357 return -EROFS;
2358
2359 /* A call inside transactions causes a deadlock. */
2360 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2361
2362 err = nilfs_segctor_sync(sci);
2363 return err;
2364}
2365
2366/**
2367 * nilfs_construct_dsync_segment - construct a data-only logical segment
2368 * @sb: super block
f30bf3e4
RK		 2369 * @inode: inode whose data blocks should be written out
2370 * @start: start byte offset
2371 * @end: end byte offset (inclusive)
9ff05123
RK		 2372 *
2373 * Return Value: On success, 0 is retured. On errors, one of the following
2374 * negative error code is returned.
2375 *
2376 * %-EROFS - Read only filesystem.
2377 *
2378 * %-EIO - I/O error
2379 *
2380 * %-ENOSPC - No space left on device (only in a panic state).
2381 *
2382 * %-ERESTARTSYS - Interrupted.
2383 *
2384 * %-ENOMEM - Insufficient memory available.
2385 */
f30bf3e4
RK		 2386int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2387 loff_t start, loff_t end)
9ff05123
RK		 2388{
2389 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2390 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2391 struct nilfs_inode_info *ii;
2392 struct nilfs_transaction_info ti;
2393 int err = 0;
2394
2395 if (!sci)
2396 return -EROFS;
2397
2398 nilfs_transaction_lock(sbi, &ti, 0);
2399
2400 ii = NILFS_I(inode);
2401 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) ||
2402 nilfs_test_opt(sbi, STRICT_ORDER) ||
2403 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2404 nilfs_discontinued(sbi->s_nilfs)) {
2405 nilfs_transaction_unlock(sbi);
2406 err = nilfs_segctor_sync(sci);
2407 return err;
2408 }
2409
2410 spin_lock(&sbi->s_inode_lock);
2411 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2412 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2413 spin_unlock(&sbi->s_inode_lock);
2414 nilfs_transaction_unlock(sbi);
2415 return 0;
2416 }
2417 spin_unlock(&sbi->s_inode_lock);
f30bf3e4
RK		 2418 sci->sc_dsync_inode = ii;
2419 sci->sc_dsync_start = start;
2420 sci->sc_dsync_end = end;
9ff05123
RK		 2421
2422 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2423
2424 nilfs_transaction_unlock(sbi);
2425 return err;
2426}
2427
2428struct nilfs_segctor_req {
2429 int mode;
2430 __u32 seq_accepted;
2431 int sc_err; /* construction failure */
2432 int sb_err; /* super block writeback failure */
2433};
2434
2435#define FLUSH_FILE_BIT (0x1) /* data file only */
2436#define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2437
2438static void nilfs_segctor_accept(struct nilfs_sc_info *sci,
2439 struct nilfs_segctor_req *req)
2440{
9ff05123
RK		 2441 req->sc_err = req->sb_err = 0;
2442 spin_lock(&sci->sc_state_lock);
2443 req->seq_accepted = sci->sc_seq_request;
2444 spin_unlock(&sci->sc_state_lock);
2445
2446 if (sci->sc_timer)
2447 del_timer_sync(sci->sc_timer);
2448}
2449
2450static void nilfs_segctor_notify(struct nilfs_sc_info *sci,
2451 struct nilfs_segctor_req *req)
2452{
2453 /* Clear requests (even when the construction failed) */
2454 spin_lock(&sci->sc_state_lock);
2455
9ff05123 2456 if (req->mode == SC_LSEG_SR) {
aeda7f63 2457 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
9ff05123
RK		 2458 sci->sc_seq_done = req->seq_accepted;
2459 nilfs_segctor_wakeup(sci, req->sc_err ? : req->sb_err);
2460 sci->sc_flush_request = 0;
aeda7f63
RK		 2461 } else {
2462 if (req->mode == SC_FLUSH_FILE)
2463 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2464 else if (req->mode == SC_FLUSH_DAT)
2465 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2466
2467 /* re-enable timer if checkpoint creation was not done */
2468 if (sci->sc_timer && (sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2469 time_before(jiffies, sci->sc_timer->expires))
2470 add_timer(sci->sc_timer);
2471 }
9ff05123
RK		 2472 spin_unlock(&sci->sc_state_lock);
2473}
2474
2475static int nilfs_segctor_construct(struct nilfs_sc_info *sci,
2476 struct nilfs_segctor_req *req)
2477{
2478 struct nilfs_sb_info *sbi = sci->sc_sbi;
2479 struct the_nilfs *nilfs = sbi->s_nilfs;
2480 int err = 0;
2481
2482 if (nilfs_discontinued(nilfs))
2483 req->mode = SC_LSEG_SR;
2484 if (!nilfs_segctor_confirm(sci)) {
2485 err = nilfs_segctor_do_construct(sci, req->mode);
2486 req->sc_err = err;
2487 }
2488 if (likely(!err)) {
2489 if (req->mode != SC_FLUSH_DAT)
2490 atomic_set(&nilfs->ns_ndirtyblks, 0);
2491 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2492 nilfs_discontinued(nilfs)) {
2493 down_write(&nilfs->ns_sem);
1dfa2710
JS		 2494 req->sb_err = nilfs_commit_super(sbi,
2495 nilfs_altsb_need_update(nilfs));
9ff05123
RK		 2496 up_write(&nilfs->ns_sem);
2497 }
2498 }
2499 return err;
2500}
2501
2502static void nilfs_construction_timeout(unsigned long data)
2503{
2504 struct task_struct *p = (struct task_struct *)data;
2505 wake_up_process(p);
2506}
2507
2508static void
2509nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2510{
2511 struct nilfs_inode_info *ii, *n;
2512
2513 list_for_each_entry_safe(ii, n, head, i_dirty) {
2514 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2515 continue;
2516 hlist_del_init(&ii->vfs_inode.i_hash);
2517 list_del_init(&ii->i_dirty);
2518 nilfs_clear_gcinode(&ii->vfs_inode);
2519 }
2520}
2521
4f6b8288
RK		 2522int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2523 void **kbufs)
9ff05123
RK		 2524{
2525 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2526 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2527 struct the_nilfs *nilfs = sbi->s_nilfs;
2528 struct nilfs_transaction_info ti;
2529 struct nilfs_segctor_req req = { .mode = SC_LSEG_SR };
2530 int err;
2531
2532 if (unlikely(!sci))
2533 return -EROFS;
2534
2535 nilfs_transaction_lock(sbi, &ti, 1);
2536
2537 err = nilfs_init_gcdat_inode(nilfs);
2538 if (unlikely(err))
2539 goto out_unlock;
071cb4b8 2540
4f6b8288 2541 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
9ff05123
RK		 2542 if (unlikely(err))
2543 goto out_unlock;
2544
071cb4b8
RK		 2545 sci->sc_freesegs = kbufs[4];
2546 sci->sc_nfreesegs = argv[4].v_nmembs;
9ff05123
RK		 2547 list_splice_init(&nilfs->ns_gc_inodes, sci->sc_gc_inodes.prev);
2548
2549 for (;;) {
2550 nilfs_segctor_accept(sci, &req);
2551 err = nilfs_segctor_construct(sci, &req);
2552 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2553 nilfs_segctor_notify(sci, &req);
2554
2555 if (likely(!err))
2556 break;
2557
2558 nilfs_warning(sb, __func__,
2559 "segment construction failed. (err=%d)", err);
2560 set_current_state(TASK_INTERRUPTIBLE);
2561 schedule_timeout(sci->sc_interval);
2562 }
2563
2564 out_unlock:
071cb4b8
RK		 2565 sci->sc_freesegs = NULL;
2566 sci->sc_nfreesegs = 0;
9ff05123
RK		 2567 nilfs_clear_gcdat_inode(nilfs);
2568 nilfs_transaction_unlock(sbi);
2569 return err;
2570}
2571
2572static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2573{
2574 struct nilfs_sb_info *sbi = sci->sc_sbi;
2575 struct nilfs_transaction_info ti;
2576 struct nilfs_segctor_req req = { .mode = mode };
2577
2578 nilfs_transaction_lock(sbi, &ti, 0);
2579
2580 nilfs_segctor_accept(sci, &req);
2581 nilfs_segctor_construct(sci, &req);
2582 nilfs_segctor_notify(sci, &req);
2583
2584 /*
2585 * Unclosed segment should be retried. We do this using sc_timer.
2586 * Timeout of sc_timer will invoke complete construction which leads
2587 * to close the current logical segment.
2588 */
2589 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2590 nilfs_segctor_start_timer(sci);
2591
2592 nilfs_transaction_unlock(sbi);
2593}
2594
2595static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2596{
2597 int mode = 0;
2598 int err;
2599
2600 spin_lock(&sci->sc_state_lock);
2601 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2602 SC_FLUSH_DAT : SC_FLUSH_FILE;
2603 spin_unlock(&sci->sc_state_lock);
2604
2605 if (mode) {
2606 err = nilfs_segctor_do_construct(sci, mode);
2607
2608 spin_lock(&sci->sc_state_lock);
2609 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2610 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2611 spin_unlock(&sci->sc_state_lock);
2612 }
2613 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2614}
2615
2616static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2617{
2618 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2619 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2620 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2621 return SC_FLUSH_FILE;
2622 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2623 return SC_FLUSH_DAT;
2624 }
2625 return SC_LSEG_SR;
2626}
2627
2628/**
2629 * nilfs_segctor_thread - main loop of the segment constructor thread.
2630 * @arg: pointer to a struct nilfs_sc_info.
2631 *
2632 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2633 * to execute segment constructions.
2634 */
2635static int nilfs_segctor_thread(void *arg)
2636{
2637 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2638 struct timer_list timer;
2639 int timeout = 0;
2640
2641 init_timer(&timer);
2642 timer.data = (unsigned long)current;
2643 timer.function = nilfs_construction_timeout;
2644 sci->sc_timer = &timer;
2645
2646 /* start sync. */
2647 sci->sc_task = current;
2648 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2649 printk(KERN_INFO
2650 "segctord starting. Construction interval = %lu seconds, "
2651 "CP frequency < %lu seconds\n",
2652 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2653
2654 spin_lock(&sci->sc_state_lock);
2655 loop:
2656 for (;;) {
2657 int mode;
2658
2659 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2660 goto end_thread;
2661
2662 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2663 mode = SC_LSEG_SR;
2664 else if (!sci->sc_flush_request)
2665 break;
2666 else
2667 mode = nilfs_segctor_flush_mode(sci);
2668
2669 spin_unlock(&sci->sc_state_lock);
2670 nilfs_segctor_thread_construct(sci, mode);
2671 spin_lock(&sci->sc_state_lock);
2672 timeout = 0;
2673 }
2674
2675
2676 if (freezing(current)) {
2677 spin_unlock(&sci->sc_state_lock);
2678 refrigerator();
2679 spin_lock(&sci->sc_state_lock);
2680 } else {
2681 DEFINE_WAIT(wait);
2682 int should_sleep = 1;
1dfa2710 2683 struct the_nilfs *nilfs;
9ff05123
RK		 2684
2685 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2686 TASK_INTERRUPTIBLE);
2687
2688 if (sci->sc_seq_request != sci->sc_seq_done)
2689 should_sleep = 0;
2690 else if (sci->sc_flush_request)
2691 should_sleep = 0;
2692 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2693 should_sleep = time_before(jiffies,
2694 sci->sc_timer->expires);
2695
2696 if (should_sleep) {
2697 spin_unlock(&sci->sc_state_lock);
2698 schedule();
2699 spin_lock(&sci->sc_state_lock);
2700 }
2701 finish_wait(&sci->sc_wait_daemon, &wait);
2702 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2703 time_after_eq(jiffies, sci->sc_timer->expires));
1dfa2710
JS		 2704 nilfs = sci->sc_sbi->s_nilfs;
2705 if (sci->sc_super->s_dirt && nilfs_sb_need_update(nilfs))
2706 set_nilfs_discontinued(nilfs);
9ff05123
RK		 2707 }
2708 goto loop;
2709
2710 end_thread:
2711 spin_unlock(&sci->sc_state_lock);
2712 del_timer_sync(sci->sc_timer);
2713 sci->sc_timer = NULL;
2714
2715 /* end sync. */
2716 sci->sc_task = NULL;
2717 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2718 return 0;
2719}
2720
2721static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2722{
2723 struct task_struct *t;
2724
2725 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2726 if (IS_ERR(t)) {
2727 int err = PTR_ERR(t);
2728
2729 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2730 err);
2731 return err;
2732 }
2733 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2734 return 0;
2735}
2736
2737static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2738{
2739 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2740
2741 while (sci->sc_task) {
2742 wake_up(&sci->sc_wait_daemon);
2743 spin_unlock(&sci->sc_state_lock);
2744 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2745 spin_lock(&sci->sc_state_lock);
2746 }
2747}
2748
cece5520 2749static int nilfs_segctor_init(struct nilfs_sc_info *sci)
9ff05123 2750{
9ff05123 2751 sci->sc_seq_done = sci->sc_seq_request;
9ff05123 2752
cece5520 2753 return nilfs_segctor_start_thread(sci);
9ff05123
RK		 2754}
2755
2756/*
2757 * Setup & clean-up functions
2758 */
2759static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi)
2760{
2761 struct nilfs_sc_info *sci;
2762
2763 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2764 if (!sci)
2765 return NULL;
2766
2767 sci->sc_sbi = sbi;
2768 sci->sc_super = sbi->s_super;
2769
2770 init_waitqueue_head(&sci->sc_wait_request);
2771 init_waitqueue_head(&sci->sc_wait_daemon);
2772 init_waitqueue_head(&sci->sc_wait_task);
2773 spin_lock_init(&sci->sc_state_lock);
2774 INIT_LIST_HEAD(&sci->sc_dirty_files);
2775 INIT_LIST_HEAD(&sci->sc_segbufs);
2776 INIT_LIST_HEAD(&sci->sc_gc_inodes);
9ff05123
RK		 2777 INIT_LIST_HEAD(&sci->sc_copied_buffers);
2778
2779 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2780 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2781 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2782
2783 if (sbi->s_interval)
2784 sci->sc_interval = sbi->s_interval;
2785 if (sbi->s_watermark)
2786 sci->sc_watermark = sbi->s_watermark;
2787 return sci;
2788}
2789
2790static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2791{
2792 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2793
2794 /* The segctord thread was stopped and its timer was removed.
2795 But some tasks remain. */
2796 do {
2797 struct nilfs_sb_info *sbi = sci->sc_sbi;
2798 struct nilfs_transaction_info ti;
2799 struct nilfs_segctor_req req = { .mode = SC_LSEG_SR };
2800
2801 nilfs_transaction_lock(sbi, &ti, 0);
2802 nilfs_segctor_accept(sci, &req);
2803 ret = nilfs_segctor_construct(sci, &req);
2804 nilfs_segctor_notify(sci, &req);
2805 nilfs_transaction_unlock(sbi);
2806
2807 } while (ret && retrycount-- > 0);
2808}
2809
2810/**
2811 * nilfs_segctor_destroy - destroy the segment constructor.
2812 * @sci: nilfs_sc_info
2813 *
2814 * nilfs_segctor_destroy() kills the segctord thread and frees
2815 * the nilfs_sc_info struct.
2816 * Caller must hold the segment semaphore.
2817 */
2818static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2819{
2820 struct nilfs_sb_info *sbi = sci->sc_sbi;
2821 int flag;
2822
2823 up_write(&sbi->s_nilfs->ns_segctor_sem);
2824
2825 spin_lock(&sci->sc_state_lock);
2826 nilfs_segctor_kill_thread(sci);
2827 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2828 || sci->sc_seq_request != sci->sc_seq_done);
2829 spin_unlock(&sci->sc_state_lock);
2830
2831 if (flag || nilfs_segctor_confirm(sci))
2832 nilfs_segctor_write_out(sci);
2833
1f5abe7e 2834 WARN_ON(!list_empty(&sci->sc_copied_buffers));
9ff05123
RK		 2835
2836 if (!list_empty(&sci->sc_dirty_files)) {
2837 nilfs_warning(sbi->s_super, __func__,
2838 "dirty file(s) after the final construction\n");
2839 nilfs_dispose_list(sbi, &sci->sc_dirty_files, 1);
2840 }
9ff05123 2841
1f5abe7e 2842 WARN_ON(!list_empty(&sci->sc_segbufs));
9ff05123 2843
9ff05123
RK		 2844 down_write(&sbi->s_nilfs->ns_segctor_sem);
2845
2846 kfree(sci);
2847}
2848
2849/**
2850 * nilfs_attach_segment_constructor - attach a segment constructor
2851 * @sbi: nilfs_sb_info
9ff05123
RK		 2852 *
2853 * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info,
2854 * initilizes it, and starts the segment constructor.
2855 *
2856 * Return Value: On success, 0 is returned. On error, one of the following
2857 * negative error code is returned.
2858 *
2859 * %-ENOMEM - Insufficient memory available.
2860 */
cece5520 2861int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi)
9ff05123
RK		 2862{
2863 struct the_nilfs *nilfs = sbi->s_nilfs;
2864 int err;
2865
2866 /* Each field of nilfs_segctor is cleared through the initialization
2867 of super-block info */
2868 sbi->s_sc_info = nilfs_segctor_new(sbi);
2869 if (!sbi->s_sc_info)
2870 return -ENOMEM;
2871
2872 nilfs_attach_writer(nilfs, sbi);
cece5520 2873 err = nilfs_segctor_init(NILFS_SC(sbi));
9ff05123
RK		 2874 if (err) {
2875 nilfs_detach_writer(nilfs, sbi);
2876 kfree(sbi->s_sc_info);
2877 sbi->s_sc_info = NULL;
2878 }
2879 return err;
2880}
2881
2882/**
2883 * nilfs_detach_segment_constructor - destroy the segment constructor
2884 * @sbi: nilfs_sb_info
2885 *
2886 * nilfs_detach_segment_constructor() kills the segment constructor daemon,
2887 * frees the struct nilfs_sc_info, and destroy the dirty file list.
2888 */
2889void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi)
2890{
2891 struct the_nilfs *nilfs = sbi->s_nilfs;
2892 LIST_HEAD(garbage_list);
2893
2894 down_write(&nilfs->ns_segctor_sem);
2895 if (NILFS_SC(sbi)) {
2896 nilfs_segctor_destroy(NILFS_SC(sbi));
2897 sbi->s_sc_info = NULL;
2898 }
2899
2900 /* Force to free the list of dirty files */
2901 spin_lock(&sbi->s_inode_lock);
2902 if (!list_empty(&sbi->s_dirty_files)) {
2903 list_splice_init(&sbi->s_dirty_files, &garbage_list);
2904 nilfs_warning(sbi->s_super, __func__,
2905 "Non empty dirty list after the last "
2906 "segment construction\n");
2907 }
2908 spin_unlock(&sbi->s_inode_lock);
2909 up_write(&nilfs->ns_segctor_sem);
2910
2911 nilfs_dispose_list(sbi, &garbage_list, 1);
2912 nilfs_detach_writer(nilfs, sbi);
2913}
Linux 6.x block layer and io_uring tree(s)