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nilfs2: get rid of sc_sbi back pointer
[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>
5a0e3ad6 35#include <linux/slab.h>
9ff05123
RK		 36#include "nilfs.h"
37#include "btnode.h"
38#include "page.h"
39#include "segment.h"
40#include "sufile.h"
41#include "cpfile.h"
42#include "ifile.h"
9ff05123
RK		 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 */
071cb4b8
RK		 82#define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
83#define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
9ff05123
RK		 84
85/* Operations depending on the construction mode and file type */
86struct nilfs_sc_operations {
87 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
88 struct inode *);
89 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
90 struct inode *);
91 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
92 struct inode *);
93 void (*write_data_binfo)(struct nilfs_sc_info *,
94 struct nilfs_segsum_pointer *,
95 union nilfs_binfo *);
96 void (*write_node_binfo)(struct nilfs_sc_info *,
97 struct nilfs_segsum_pointer *,
98 union nilfs_binfo *);
99};
100
101/*
102 * Other definitions
103 */
104static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
105static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
106static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
693dd321 107static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
9ff05123
RK		 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
9ff05123
RK		 118static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
119{
120 struct nilfs_transaction_info *cur_ti = current->journal_info;
121 void *save = NULL;
122
123 if (cur_ti) {
124 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
125 return ++cur_ti->ti_count;
126 else {
127 /*
128 * If journal_info field is occupied by other FS,
47420c79
RK		 129 * it is saved and will be restored on
130 * nilfs_transaction_commit().
9ff05123
RK		 131 */
132 printk(KERN_WARNING
133 "NILFS warning: journal info from a different "
134 "FS\n");
135 save = current->journal_info;
136 }
137 }
138 if (!ti) {
139 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
140 if (!ti)
141 return -ENOMEM;
142 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
143 } else {
144 ti->ti_flags = 0;
145 }
146 ti->ti_count = 0;
147 ti->ti_save = save;
148 ti->ti_magic = NILFS_TI_MAGIC;
149 current->journal_info = ti;
150 return 0;
151}
152
153/**
154 * nilfs_transaction_begin - start indivisible file operations.
155 * @sb: super block
156 * @ti: nilfs_transaction_info
157 * @vacancy_check: flags for vacancy rate checks
158 *
159 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
160 * the segment semaphore, to make a segment construction and write tasks
47420c79 161 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
9ff05123
RK		 162 * The region enclosed by these two functions can be nested. To avoid a
163 * deadlock, the semaphore is only acquired or released in the outermost call.
164 *
165 * This function allocates a nilfs_transaction_info struct to keep context
166 * information on it. It is initialized and hooked onto the current task in
167 * the outermost call. If a pre-allocated struct is given to @ti, it is used
7a65004b 168 * instead; otherwise a new struct is assigned from a slab.
9ff05123
RK		 169 *
170 * When @vacancy_check flag is set, this function will check the amount of
171 * free space, and will wait for the GC to reclaim disk space if low capacity.
172 *
173 * Return Value: On success, 0 is returned. On error, one of the following
174 * negative error code is returned.
175 *
176 * %-ENOMEM - Insufficient memory available.
177 *
9ff05123
RK		 178 * %-ENOSPC - No space left on device
179 */
180int nilfs_transaction_begin(struct super_block *sb,
181 struct nilfs_transaction_info *ti,
182 int vacancy_check)
183{
184 struct nilfs_sb_info *sbi;
185 struct the_nilfs *nilfs;
186 int ret = nilfs_prepare_segment_lock(ti);
187
188 if (unlikely(ret < 0))
189 return ret;
190 if (ret > 0)
191 return 0;
192
5beb6e0b
RK		 193 vfs_check_frozen(sb, SB_FREEZE_WRITE);
194
9ff05123
RK		 195 sbi = NILFS_SB(sb);
196 nilfs = sbi->s_nilfs;
197 down_read(&nilfs->ns_segctor_sem);
198 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
199 up_read(&nilfs->ns_segctor_sem);
200 ret = -ENOSPC;
201 goto failed;
202 }
203 return 0;
204
205 failed:
206 ti = current->journal_info;
207 current->journal_info = ti->ti_save;
208 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
209 kmem_cache_free(nilfs_transaction_cachep, ti);
210 return ret;
211}
212
213/**
47420c79 214 * nilfs_transaction_commit - commit indivisible file operations.
9ff05123 215 * @sb: super block
9ff05123 216 *
47420c79
RK		 217 * nilfs_transaction_commit() releases the read semaphore which is
218 * acquired by nilfs_transaction_begin(). This is only performed
219 * in outermost call of this function. If a commit flag is set,
220 * nilfs_transaction_commit() sets a timer to start the segment
221 * constructor. If a sync flag is set, it starts construction
222 * directly.
9ff05123 223 */
47420c79 224int nilfs_transaction_commit(struct super_block *sb)
9ff05123
RK		 225{
226 struct nilfs_transaction_info *ti = current->journal_info;
3fd3fe5a 227 struct the_nilfs *nilfs = NILFS_SB(sb)->s_nilfs;
9ff05123
RK		 228 int err = 0;
229
230 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
47420c79 231 ti->ti_flags |= NILFS_TI_COMMIT;
9ff05123
RK		 232 if (ti->ti_count > 0) {
233 ti->ti_count--;
234 return 0;
235 }
3fd3fe5a
RK		 236 if (nilfs->ns_writer) {
237 struct nilfs_sc_info *sci = nilfs->ns_writer;
238
9ff05123
RK		 239 if (ti->ti_flags & NILFS_TI_COMMIT)
240 nilfs_segctor_start_timer(sci);
3fd3fe5a 241 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
9ff05123
RK		 242 nilfs_segctor_do_flush(sci, 0);
243 }
3fd3fe5a 244 up_read(&nilfs->ns_segctor_sem);
9ff05123
RK		 245 current->journal_info = ti->ti_save;
246
247 if (ti->ti_flags & NILFS_TI_SYNC)
248 err = nilfs_construct_segment(sb);
249 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
250 kmem_cache_free(nilfs_transaction_cachep, ti);
251 return err;
252}
253
47420c79
RK		 254void nilfs_transaction_abort(struct super_block *sb)
255{
256 struct nilfs_transaction_info *ti = current->journal_info;
257
258 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
259 if (ti->ti_count > 0) {
260 ti->ti_count--;
261 return;
262 }
263 up_read(&NILFS_SB(sb)->s_nilfs->ns_segctor_sem);
264
265 current->journal_info = ti->ti_save;
266 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
267 kmem_cache_free(nilfs_transaction_cachep, ti);
268}
269
9ff05123
RK		 270void nilfs_relax_pressure_in_lock(struct super_block *sb)
271{
3fd3fe5a
RK		 272 struct the_nilfs *nilfs = NILFS_SB(sb)->s_nilfs;
273 struct nilfs_sc_info *sci = nilfs->ns_writer;
9ff05123
RK		 274
275 if (!sci || !sci->sc_flush_request)
276 return;
277
278 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
279 up_read(&nilfs->ns_segctor_sem);
280
281 down_write(&nilfs->ns_segctor_sem);
282 if (sci->sc_flush_request &&
283 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
284 struct nilfs_transaction_info *ti = current->journal_info;
285
286 ti->ti_flags |= NILFS_TI_WRITER;
287 nilfs_segctor_do_immediate_flush(sci);
288 ti->ti_flags &= ~NILFS_TI_WRITER;
289 }
290 downgrade_write(&nilfs->ns_segctor_sem);
291}
292
293static void nilfs_transaction_lock(struct nilfs_sb_info *sbi,
294 struct nilfs_transaction_info *ti,
295 int gcflag)
296{
297 struct nilfs_transaction_info *cur_ti = current->journal_info;
3fd3fe5a
RK		 298 struct the_nilfs *nilfs = sbi->s_nilfs;
299 struct nilfs_sc_info *sci = nilfs->ns_writer;
9ff05123 300
1f5abe7e 301 WARN_ON(cur_ti);
9ff05123
RK		 302 ti->ti_flags = NILFS_TI_WRITER;
303 ti->ti_count = 0;
304 ti->ti_save = cur_ti;
305 ti->ti_magic = NILFS_TI_MAGIC;
306 INIT_LIST_HEAD(&ti->ti_garbage);
307 current->journal_info = ti;
308
309 for (;;) {
3fd3fe5a
RK		 310 down_write(&nilfs->ns_segctor_sem);
311 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
9ff05123
RK		 312 break;
313
3fd3fe5a 314 nilfs_segctor_do_immediate_flush(sci);
9ff05123
RK		 315
316 up_write(&sbi->s_nilfs->ns_segctor_sem);
317 yield();
318 }
319 if (gcflag)
320 ti->ti_flags |= NILFS_TI_GC;
321}
322
323static void nilfs_transaction_unlock(struct nilfs_sb_info *sbi)
324{
325 struct nilfs_transaction_info *ti = current->journal_info;
693dd321 326 struct the_nilfs *nilfs = sbi->s_nilfs;
9ff05123
RK		 327
328 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
329 BUG_ON(ti->ti_count > 0);
330
693dd321 331 up_write(&nilfs->ns_segctor_sem);
9ff05123
RK		 332 current->journal_info = ti->ti_save;
333 if (!list_empty(&ti->ti_garbage))
693dd321 334 nilfs_dispose_list(nilfs, &ti->ti_garbage, 0);
9ff05123
RK		 335}
336
337static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
338 struct nilfs_segsum_pointer *ssp,
339 unsigned bytes)
340{
341 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
342 unsigned blocksize = sci->sc_super->s_blocksize;
343 void *p;
344
345 if (unlikely(ssp->offset + bytes > blocksize)) {
346 ssp->offset = 0;
347 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
348 &segbuf->sb_segsum_buffers));
349 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
350 }
351 p = ssp->bh->b_data + ssp->offset;
352 ssp->offset += bytes;
353 return p;
354}
355
356/**
357 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
358 * @sci: nilfs_sc_info
359 */
360static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
361{
362 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
363 struct buffer_head *sumbh;
364 unsigned sumbytes;
365 unsigned flags = 0;
366 int err;
367
368 if (nilfs_doing_gc())
369 flags = NILFS_SS_GC;
6c43f410 370 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
9ff05123
RK		 371 if (unlikely(err))
372 return err;
373
374 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
375 sumbytes = segbuf->sb_sum.sumbytes;
376 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
377 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
378 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
379 return 0;
380}
381
382static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
383{
384 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
385 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
386 return -E2BIG; /* The current segment is filled up
387 (internal code) */
388 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
389 return nilfs_segctor_reset_segment_buffer(sci);
390}
391
392static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
393{
394 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
395 int err;
396
397 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
398 err = nilfs_segctor_feed_segment(sci);
399 if (err)
400 return err;
401 segbuf = sci->sc_curseg;
402 }
1e2b68bf 403 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
9ff05123
RK		 404 if (likely(!err))
405 segbuf->sb_sum.flags |= NILFS_SS_SR;
406 return err;
407}
408
409/*
410 * Functions for making segment summary and payloads
411 */
412static int nilfs_segctor_segsum_block_required(
413 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
414 unsigned binfo_size)
415{
416 unsigned blocksize = sci->sc_super->s_blocksize;
417 /* Size of finfo and binfo is enough small against blocksize */
418
419 return ssp->offset + binfo_size +
420 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
421 blocksize;
422}
423
424static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
425 struct inode *inode)
426{
427 sci->sc_curseg->sb_sum.nfinfo++;
428 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
429 nilfs_segctor_map_segsum_entry(
430 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
c96fa464 431
72746ac6
RK		 432 if (NILFS_I(inode)->i_root &&
433 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
c96fa464 434 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
9ff05123
RK		 435 /* skip finfo */
436}
437
438static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
439 struct inode *inode)
440{
441 struct nilfs_finfo *finfo;
442 struct nilfs_inode_info *ii;
443 struct nilfs_segment_buffer *segbuf;
6c43f410 444 __u64 cno;
9ff05123
RK		 445
446 if (sci->sc_blk_cnt == 0)
447 return;
448
449 ii = NILFS_I(inode);
6c43f410
RK		 450
451 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
452 cno = ii->i_cno;
453 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
454 cno = 0;
455 else
456 cno = sci->sc_cno;
457
9ff05123
RK		 458 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
459 sizeof(*finfo));
460 finfo->fi_ino = cpu_to_le64(inode->i_ino);
461 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
462 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
6c43f410 463 finfo->fi_cno = cpu_to_le64(cno);
9ff05123
RK		 464
465 segbuf = sci->sc_curseg;
466 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
467 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
468 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
469 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
470}
471
472static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
473 struct buffer_head *bh,
474 struct inode *inode,
475 unsigned binfo_size)
476{
477 struct nilfs_segment_buffer *segbuf;
478 int required, err = 0;
479
480 retry:
481 segbuf = sci->sc_curseg;
482 required = nilfs_segctor_segsum_block_required(
483 sci, &sci->sc_binfo_ptr, binfo_size);
484 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
485 nilfs_segctor_end_finfo(sci, inode);
486 err = nilfs_segctor_feed_segment(sci);
487 if (err)
488 return err;
489 goto retry;
490 }
491 if (unlikely(required)) {
492 err = nilfs_segbuf_extend_segsum(segbuf);
493 if (unlikely(err))
494 goto failed;
495 }
496 if (sci->sc_blk_cnt == 0)
497 nilfs_segctor_begin_finfo(sci, inode);
498
499 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
500 /* Substitution to vblocknr is delayed until update_blocknr() */
501 nilfs_segbuf_add_file_buffer(segbuf, bh);
502 sci->sc_blk_cnt++;
503 failed:
504 return err;
505}
506
9ff05123
RK		 507/*
508 * Callback functions that enumerate, mark, and collect dirty blocks
509 */
510static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
511 struct buffer_head *bh, struct inode *inode)
512{
513 int err;
514
9ff05123 515 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
e828949e
RK		 516 if (err < 0)
517 return err;
9ff05123
RK		 518
519 err = nilfs_segctor_add_file_block(sci, bh, inode,
520 sizeof(struct nilfs_binfo_v));
521 if (!err)
522 sci->sc_datablk_cnt++;
523 return err;
524}
525
526static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
527 struct buffer_head *bh,
528 struct inode *inode)
529{
e828949e 530 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
9ff05123
RK		 531}
532
533static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
534 struct buffer_head *bh,
535 struct inode *inode)
536{
1f5abe7e 537 WARN_ON(!buffer_dirty(bh));
9ff05123
RK		 538 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
539}
540
541static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
542 struct nilfs_segsum_pointer *ssp,
543 union nilfs_binfo *binfo)
544{
545 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
546 sci, ssp, sizeof(*binfo_v));
547 *binfo_v = binfo->bi_v;
548}
549
550static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
551 struct nilfs_segsum_pointer *ssp,
552 union nilfs_binfo *binfo)
553{
554 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
555 sci, ssp, sizeof(*vblocknr));
556 *vblocknr = binfo->bi_v.bi_vblocknr;
557}
558
4e819509 559static struct nilfs_sc_operations nilfs_sc_file_ops = {
9ff05123
RK		 560 .collect_data = nilfs_collect_file_data,
561 .collect_node = nilfs_collect_file_node,
562 .collect_bmap = nilfs_collect_file_bmap,
563 .write_data_binfo = nilfs_write_file_data_binfo,
564 .write_node_binfo = nilfs_write_file_node_binfo,
565};
566
567static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
568 struct buffer_head *bh, struct inode *inode)
569{
570 int err;
571
572 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
e828949e
RK		 573 if (err < 0)
574 return err;
9ff05123
RK		 575
576 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
577 if (!err)
578 sci->sc_datablk_cnt++;
579 return err;
580}
581
582static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
583 struct buffer_head *bh, struct inode *inode)
584{
1f5abe7e 585 WARN_ON(!buffer_dirty(bh));
9ff05123
RK		 586 return nilfs_segctor_add_file_block(sci, bh, inode,
587 sizeof(struct nilfs_binfo_dat));
588}
589
590static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
591 struct nilfs_segsum_pointer *ssp,
592 union nilfs_binfo *binfo)
593{
594 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
595 sizeof(*blkoff));
596 *blkoff = binfo->bi_dat.bi_blkoff;
597}
598
599static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
600 struct nilfs_segsum_pointer *ssp,
601 union nilfs_binfo *binfo)
602{
603 struct nilfs_binfo_dat *binfo_dat =
604 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
605 *binfo_dat = binfo->bi_dat;
606}
607
4e819509 608static struct nilfs_sc_operations nilfs_sc_dat_ops = {
9ff05123
RK		 609 .collect_data = nilfs_collect_dat_data,
610 .collect_node = nilfs_collect_file_node,
611 .collect_bmap = nilfs_collect_dat_bmap,
612 .write_data_binfo = nilfs_write_dat_data_binfo,
613 .write_node_binfo = nilfs_write_dat_node_binfo,
614};
615
4e819509 616static struct nilfs_sc_operations nilfs_sc_dsync_ops = {
9ff05123
RK		 617 .collect_data = nilfs_collect_file_data,
618 .collect_node = NULL,
619 .collect_bmap = NULL,
620 .write_data_binfo = nilfs_write_file_data_binfo,
621 .write_node_binfo = NULL,
622};
623
f30bf3e4
RK		 624static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
625 struct list_head *listp,
626 size_t nlimit,
627 loff_t start, loff_t end)
9ff05123 628{
9ff05123
RK		 629 struct address_space *mapping = inode->i_mapping;
630 struct pagevec pvec;
f30bf3e4
RK		 631 pgoff_t index = 0, last = ULONG_MAX;
632 size_t ndirties = 0;
633 int i;
9ff05123 634
f30bf3e4
RK		 635 if (unlikely(start != 0 || end != LLONG_MAX)) {
636 /*
637 * A valid range is given for sync-ing data pages. The
638 * range is rounded to per-page; extra dirty buffers
639 * may be included if blocksize < pagesize.
640 */
641 index = start >> PAGE_SHIFT;
642 last = end >> PAGE_SHIFT;
643 }
9ff05123
RK		 644 pagevec_init(&pvec, 0);
645 repeat:
f30bf3e4
RK		 646 if (unlikely(index > last) ||
647 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
648 min_t(pgoff_t, last - index,
649 PAGEVEC_SIZE - 1) + 1))
650 return ndirties;
9ff05123
RK		 651
652 for (i = 0; i < pagevec_count(&pvec); i++) {
653 struct buffer_head *bh, *head;
654 struct page *page = pvec.pages[i];
655
f30bf3e4
RK		 656 if (unlikely(page->index > last))
657 break;
658
9ff05123
RK		 659 if (mapping->host) {
660 lock_page(page);
661 if (!page_has_buffers(page))
662 create_empty_buffers(page,
663 1 << inode->i_blkbits, 0);
664 unlock_page(page);
665 }
666
667 bh = head = page_buffers(page);
668 do {
f30bf3e4
RK		 669 if (!buffer_dirty(bh))
670 continue;
671 get_bh(bh);
672 list_add_tail(&bh->b_assoc_buffers, listp);
673 ndirties++;
674 if (unlikely(ndirties >= nlimit)) {
675 pagevec_release(&pvec);
676 cond_resched();
677 return ndirties;
9ff05123 678 }
f30bf3e4 679 } while (bh = bh->b_this_page, bh != head);
9ff05123
RK		 680 }
681 pagevec_release(&pvec);
682 cond_resched();
f30bf3e4 683 goto repeat;
9ff05123
RK		 684}
685
686static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
687 struct list_head *listp)
688{
689 struct nilfs_inode_info *ii = NILFS_I(inode);
690 struct address_space *mapping = &ii->i_btnode_cache;
691 struct pagevec pvec;
692 struct buffer_head *bh, *head;
693 unsigned int i;
694 pgoff_t index = 0;
695
696 pagevec_init(&pvec, 0);
697
698 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
699 PAGEVEC_SIZE)) {
700 for (i = 0; i < pagevec_count(&pvec); i++) {
701 bh = head = page_buffers(pvec.pages[i]);
702 do {
703 if (buffer_dirty(bh)) {
704 get_bh(bh);
705 list_add_tail(&bh->b_assoc_buffers,
706 listp);
707 }
708 bh = bh->b_this_page;
709 } while (bh != head);
710 }
711 pagevec_release(&pvec);
712 cond_resched();
713 }
714}
715
693dd321 716static void nilfs_dispose_list(struct the_nilfs *nilfs,
9ff05123
RK		 717 struct list_head *head, int force)
718{
719 struct nilfs_inode_info *ii, *n;
720 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
721 unsigned nv = 0;
722
723 while (!list_empty(head)) {
693dd321 724 spin_lock(&nilfs->ns_inode_lock);
9ff05123
RK		 725 list_for_each_entry_safe(ii, n, head, i_dirty) {
726 list_del_init(&ii->i_dirty);
727 if (force) {
728 if (unlikely(ii->i_bh)) {
729 brelse(ii->i_bh);
730 ii->i_bh = NULL;
731 }
732 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
733 set_bit(NILFS_I_QUEUED, &ii->i_state);
734 list_add_tail(&ii->i_dirty,
693dd321 735 &nilfs->ns_dirty_files);
9ff05123
RK		 736 continue;
737 }
738 ivec[nv++] = ii;
739 if (nv == SC_N_INODEVEC)
740 break;
741 }
693dd321 742 spin_unlock(&nilfs->ns_inode_lock);
9ff05123
RK		 743
744 for (pii = ivec; nv > 0; pii++, nv--)
745 iput(&(*pii)->vfs_inode);
746 }
747}
748
e912a5b6
RK		 749static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
750 struct nilfs_root *root)
9ff05123 751{
9ff05123
RK		 752 int ret = 0;
753
e912a5b6 754 if (nilfs_mdt_fetch_dirty(root->ifile))
9ff05123
RK		 755 ret++;
756 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
757 ret++;
758 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
759 ret++;
365e215c
RK		 760 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
761 ret++;
9ff05123
RK		 762 return ret;
763}
764
765static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
766{
767 return list_empty(&sci->sc_dirty_files) &&
768 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
071cb4b8 769 sci->sc_nfreesegs == 0 &&
9ff05123
RK		 770 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
771}
772
773static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
774{
d96bbfa2 775 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123
RK		 776 int ret = 0;
777
693dd321 778 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
9ff05123
RK		 779 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
780
693dd321
RK		 781 spin_lock(&nilfs->ns_inode_lock);
782 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
9ff05123
RK		 783 ret++;
784
693dd321 785 spin_unlock(&nilfs->ns_inode_lock);
9ff05123
RK		 786 return ret;
787}
788
789static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
790{
d96bbfa2 791 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123 792
e912a5b6 793 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
9ff05123
RK		 794 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
795 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
365e215c 796 nilfs_mdt_clear_dirty(nilfs->ns_dat);
9ff05123
RK		 797}
798
799static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
800{
d96bbfa2 801 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123
RK		 802 struct buffer_head *bh_cp;
803 struct nilfs_checkpoint *raw_cp;
804 int err;
805
806 /* XXX: this interface will be changed */
807 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
808 &raw_cp, &bh_cp);
809 if (likely(!err)) {
810 /* The following code is duplicated with cpfile. But, it is
811 needed to collect the checkpoint even if it was not newly
812 created */
813 nilfs_mdt_mark_buffer_dirty(bh_cp);
814 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
815 nilfs_cpfile_put_checkpoint(
816 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
1f5abe7e
RK		 817 } else
818 WARN_ON(err == -EINVAL || err == -ENOENT);
819
9ff05123
RK		 820 return err;
821}
822
823static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
824{
d96bbfa2 825 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123
RK		 826 struct buffer_head *bh_cp;
827 struct nilfs_checkpoint *raw_cp;
828 int err;
829
830 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
831 &raw_cp, &bh_cp);
832 if (unlikely(err)) {
1f5abe7e 833 WARN_ON(err == -EINVAL || err == -ENOENT);
9ff05123
RK		 834 goto failed_ibh;
835 }
836 raw_cp->cp_snapshot_list.ssl_next = 0;
837 raw_cp->cp_snapshot_list.ssl_prev = 0;
838 raw_cp->cp_inodes_count =
b7c06342 839 cpu_to_le64(atomic_read(&sci->sc_root->inodes_count));
9ff05123 840 raw_cp->cp_blocks_count =
b7c06342 841 cpu_to_le64(atomic_read(&sci->sc_root->blocks_count));
9ff05123
RK		 842 raw_cp->cp_nblk_inc =
843 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
844 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
845 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
458c5b08 846
c96fa464
RK		 847 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
848 nilfs_checkpoint_clear_minor(raw_cp);
849 else
850 nilfs_checkpoint_set_minor(raw_cp);
851
e912a5b6
RK		 852 nilfs_write_inode_common(sci->sc_root->ifile,
853 &raw_cp->cp_ifile_inode, 1);
9ff05123
RK		 854 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
855 return 0;
856
857 failed_ibh:
858 return err;
859}
860
861static void nilfs_fill_in_file_bmap(struct inode *ifile,
862 struct nilfs_inode_info *ii)
863
864{
865 struct buffer_head *ibh;
866 struct nilfs_inode *raw_inode;
867
868 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
869 ibh = ii->i_bh;
870 BUG_ON(!ibh);
871 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
872 ibh);
873 nilfs_bmap_write(ii->i_bmap, raw_inode);
874 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
875 }
876}
877
e912a5b6 878static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
9ff05123
RK		 879{
880 struct nilfs_inode_info *ii;
881
882 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
e912a5b6 883 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
9ff05123
RK		 884 set_bit(NILFS_I_COLLECTED, &ii->i_state);
885 }
9ff05123
RK		 886}
887
9ff05123
RK		 888static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
889 struct the_nilfs *nilfs)
890{
1e2b68bf
RK		 891 struct buffer_head *bh_sr;
892 struct nilfs_super_root *raw_sr;
9ff05123
RK		 893 unsigned isz = nilfs->ns_inode_size;
894
1e2b68bf
RK		 895 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
896 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
897
9ff05123
RK		 898 raw_sr->sr_bytes = cpu_to_le16(NILFS_SR_BYTES);
899 raw_sr->sr_nongc_ctime
900 = cpu_to_le64(nilfs_doing_gc() ?
901 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
902 raw_sr->sr_flags = 0;
903
365e215c 904 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
3961f0e2
RK		 905 NILFS_SR_DAT_OFFSET(isz), 1);
906 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
907 NILFS_SR_CPFILE_OFFSET(isz), 1);
908 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
909 NILFS_SR_SUFILE_OFFSET(isz), 1);
9ff05123
RK		 910}
911
912static void nilfs_redirty_inodes(struct list_head *head)
913{
914 struct nilfs_inode_info *ii;
915
916 list_for_each_entry(ii, head, i_dirty) {
917 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
918 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
919 }
920}
921
922static void nilfs_drop_collected_inodes(struct list_head *head)
923{
924 struct nilfs_inode_info *ii;
925
926 list_for_each_entry(ii, head, i_dirty) {
927 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
928 continue;
929
930 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
931 set_bit(NILFS_I_UPDATED, &ii->i_state);
932 }
933}
934
9ff05123
RK		 935static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
936 struct inode *inode,
937 struct list_head *listp,
938 int (*collect)(struct nilfs_sc_info *,
939 struct buffer_head *,
940 struct inode *))
941{
942 struct buffer_head *bh, *n;
943 int err = 0;
944
945 if (collect) {
946 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
947 list_del_init(&bh->b_assoc_buffers);
948 err = collect(sci, bh, inode);
949 brelse(bh);
950 if (unlikely(err))
951 goto dispose_buffers;
952 }
953 return 0;
954 }
955
956 dispose_buffers:
957 while (!list_empty(listp)) {
958 bh = list_entry(listp->next, struct buffer_head,
959 b_assoc_buffers);
960 list_del_init(&bh->b_assoc_buffers);
961 brelse(bh);
962 }
963 return err;
964}
965
f30bf3e4
RK		 966static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
967{
968 /* Remaining number of blocks within segment buffer */
969 return sci->sc_segbuf_nblocks -
970 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
971}
972
9ff05123
RK		 973static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
974 struct inode *inode,
975 struct nilfs_sc_operations *sc_ops)
976{
977 LIST_HEAD(data_buffers);
978 LIST_HEAD(node_buffers);
f30bf3e4 979 int err;
9ff05123
RK		 980
981 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
f30bf3e4
RK		 982 size_t n, rest = nilfs_segctor_buffer_rest(sci);
983
984 n = nilfs_lookup_dirty_data_buffers(
985 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
986 if (n > rest) {
987 err = nilfs_segctor_apply_buffers(
9ff05123 988 sci, inode, &data_buffers,
f30bf3e4
RK		 989 sc_ops->collect_data);
990 BUG_ON(!err); /* always receive -E2BIG or true error */
9ff05123
RK		 991 goto break_or_fail;
992 }
993 }
994 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
995
996 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
997 err = nilfs_segctor_apply_buffers(
998 sci, inode, &data_buffers, sc_ops->collect_data);
999 if (unlikely(err)) {
1000 /* dispose node list */
1001 nilfs_segctor_apply_buffers(
1002 sci, inode, &node_buffers, NULL);
1003 goto break_or_fail;
1004 }
1005 sci->sc_stage.flags |= NILFS_CF_NODE;
1006 }
1007 /* Collect node */
1008 err = nilfs_segctor_apply_buffers(
1009 sci, inode, &node_buffers, sc_ops->collect_node);
1010 if (unlikely(err))
1011 goto break_or_fail;
1012
1013 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1014 err = nilfs_segctor_apply_buffers(
1015 sci, inode, &node_buffers, sc_ops->collect_bmap);
1016 if (unlikely(err))
1017 goto break_or_fail;
1018
1019 nilfs_segctor_end_finfo(sci, inode);
1020 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1021
1022 break_or_fail:
1023 return err;
1024}
1025
1026static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1027 struct inode *inode)
1028{
1029 LIST_HEAD(data_buffers);
f30bf3e4
RK		 1030 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1031 int err;
9ff05123 1032
f30bf3e4
RK		 1033 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1034 sci->sc_dsync_start,
1035 sci->sc_dsync_end);
1036
1037 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1038 nilfs_collect_file_data);
1039 if (!err) {
9ff05123 1040 nilfs_segctor_end_finfo(sci, inode);
f30bf3e4
RK		 1041 BUG_ON(n > rest);
1042 /* always receive -E2BIG or true error if n > rest */
1043 }
9ff05123
RK		 1044 return err;
1045}
1046
1047static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1048{
d96bbfa2 1049 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123
RK		 1050 struct list_head *head;
1051 struct nilfs_inode_info *ii;
071cb4b8 1052 size_t ndone;
9ff05123
RK		 1053 int err = 0;
1054
1055 switch (sci->sc_stage.scnt) {
1056 case NILFS_ST_INIT:
1057 /* Pre-processes */
1058 sci->sc_stage.flags = 0;
1059
1060 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1061 sci->sc_nblk_inc = 0;
1062 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1063 if (mode == SC_LSEG_DSYNC) {
1064 sci->sc_stage.scnt = NILFS_ST_DSYNC;
1065 goto dsync_mode;
1066 }
1067 }
1068
1069 sci->sc_stage.dirty_file_ptr = NULL;
1070 sci->sc_stage.gc_inode_ptr = NULL;
1071 if (mode == SC_FLUSH_DAT) {
1072 sci->sc_stage.scnt = NILFS_ST_DAT;
1073 goto dat_stage;
1074 }
1075 sci->sc_stage.scnt++; /* Fall through */
1076 case NILFS_ST_GC:
1077 if (nilfs_doing_gc()) {
1078 head = &sci->sc_gc_inodes;
1079 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1080 head, i_dirty);
1081 list_for_each_entry_continue(ii, head, i_dirty) {
1082 err = nilfs_segctor_scan_file(
1083 sci, &ii->vfs_inode,
1084 &nilfs_sc_file_ops);
1085 if (unlikely(err)) {
1086 sci->sc_stage.gc_inode_ptr = list_entry(
1087 ii->i_dirty.prev,
1088 struct nilfs_inode_info,
1089 i_dirty);
1090 goto break_or_fail;
1091 }
1092 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1093 }
1094 sci->sc_stage.gc_inode_ptr = NULL;
1095 }
1096 sci->sc_stage.scnt++; /* Fall through */
1097 case NILFS_ST_FILE:
1098 head = &sci->sc_dirty_files;
1099 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1100 i_dirty);
1101 list_for_each_entry_continue(ii, head, i_dirty) {
1102 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1103
1104 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1105 &nilfs_sc_file_ops);
1106 if (unlikely(err)) {
1107 sci->sc_stage.dirty_file_ptr =
1108 list_entry(ii->i_dirty.prev,
1109 struct nilfs_inode_info,
1110 i_dirty);
1111 goto break_or_fail;
1112 }
1113 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1114 /* XXX: required ? */
1115 }
1116 sci->sc_stage.dirty_file_ptr = NULL;
1117 if (mode == SC_FLUSH_FILE) {
1118 sci->sc_stage.scnt = NILFS_ST_DONE;
1119 return 0;
1120 }
9ff05123
RK		 1121 sci->sc_stage.scnt++;
1122 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1123 /* Fall through */
1124 case NILFS_ST_IFILE:
e912a5b6 1125 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
9ff05123
RK		 1126 &nilfs_sc_file_ops);
1127 if (unlikely(err))
1128 break;
1129 sci->sc_stage.scnt++;
1130 /* Creating a checkpoint */
1131 err = nilfs_segctor_create_checkpoint(sci);
1132 if (unlikely(err))
1133 break;
1134 /* Fall through */
1135 case NILFS_ST_CPFILE:
1136 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1137 &nilfs_sc_file_ops);
1138 if (unlikely(err))
1139 break;
1140 sci->sc_stage.scnt++; /* Fall through */
1141 case NILFS_ST_SUFILE:
071cb4b8
RK		 1142 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1143 sci->sc_nfreesegs, &ndone);
1144 if (unlikely(err)) {
1145 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1146 sci->sc_freesegs, ndone,
1147 NULL);
9ff05123 1148 break;
071cb4b8
RK		 1149 }
1150 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1151
9ff05123
RK		 1152 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1153 &nilfs_sc_file_ops);
1154 if (unlikely(err))
1155 break;
1156 sci->sc_stage.scnt++; /* Fall through */
1157 case NILFS_ST_DAT:
1158 dat_stage:
365e215c 1159 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
9ff05123
RK		 1160 &nilfs_sc_dat_ops);
1161 if (unlikely(err))
1162 break;
1163 if (mode == SC_FLUSH_DAT) {
1164 sci->sc_stage.scnt = NILFS_ST_DONE;
1165 return 0;
1166 }
1167 sci->sc_stage.scnt++; /* Fall through */
1168 case NILFS_ST_SR:
1169 if (mode == SC_LSEG_SR) {
1170 /* Appending a super root */
1171 err = nilfs_segctor_add_super_root(sci);
1172 if (unlikely(err))
1173 break;
1174 }
1175 /* End of a logical segment */
1176 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1177 sci->sc_stage.scnt = NILFS_ST_DONE;
1178 return 0;
1179 case NILFS_ST_DSYNC:
1180 dsync_mode:
1181 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
f30bf3e4 1182 ii = sci->sc_dsync_inode;
9ff05123
RK		 1183 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1184 break;
1185
1186 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1187 if (unlikely(err))
1188 break;
9ff05123
RK		 1189 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1190 sci->sc_stage.scnt = NILFS_ST_DONE;
1191 return 0;
1192 case NILFS_ST_DONE:
1193 return 0;
1194 default:
1195 BUG();
1196 }
1197
1198 break_or_fail:
1199 return err;
1200}
1201
a694291a
RK		 1202/**
1203 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1204 * @sci: nilfs_sc_info
1205 * @nilfs: nilfs object
1206 */
9ff05123
RK		 1207static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1208 struct the_nilfs *nilfs)
1209{
a694291a 1210 struct nilfs_segment_buffer *segbuf, *prev;
9ff05123 1211 __u64 nextnum;
a694291a 1212 int err, alloc = 0;
9ff05123 1213
a694291a
RK		 1214 segbuf = nilfs_segbuf_new(sci->sc_super);
1215 if (unlikely(!segbuf))
1216 return -ENOMEM;
9ff05123 1217
a694291a
RK		 1218 if (list_empty(&sci->sc_write_logs)) {
1219 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1220 nilfs->ns_pseg_offset, nilfs);
1221 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1222 nilfs_shift_to_next_segment(nilfs);
1223 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1224 }
9ff05123 1225
a694291a
RK		 1226 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1227 nextnum = nilfs->ns_nextnum;
1228
1229 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1230 /* Start from the head of a new full segment */
1231 alloc++;
1232 } else {
1233 /* Continue logs */
1234 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1235 nilfs_segbuf_map_cont(segbuf, prev);
1236 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1237 nextnum = prev->sb_nextnum;
1238
1239 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1240 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1241 segbuf->sb_sum.seg_seq++;
1242 alloc++;
1243 }
9ff05123 1244 }
9ff05123 1245
61a189e9 1246 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
a694291a
RK		 1247 if (err)
1248 goto failed;
9ff05123 1249
a694291a 1250 if (alloc) {
cece5520 1251 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
a694291a
RK		 1252 if (err)
1253 goto failed;
1254 }
9ff05123
RK		 1255 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1256
a694291a
RK		 1257 BUG_ON(!list_empty(&sci->sc_segbufs));
1258 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1259 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
cece5520 1260 return 0;
a694291a
RK		 1261
1262 failed:
1263 nilfs_segbuf_free(segbuf);
1264 return err;
9ff05123
RK		 1265}
1266
1267static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1268 struct the_nilfs *nilfs, int nadd)
1269{
e29df395 1270 struct nilfs_segment_buffer *segbuf, *prev;
9ff05123
RK		 1271 struct inode *sufile = nilfs->ns_sufile;
1272 __u64 nextnextnum;
1273 LIST_HEAD(list);
1274 int err, ret, i;
1275
1276 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1277 /*
1278 * Since the segment specified with nextnum might be allocated during
1279 * the previous construction, the buffer including its segusage may
1280 * not be dirty. The following call ensures that the buffer is dirty
1281 * and will pin the buffer on memory until the sufile is written.
1282 */
61a189e9 1283 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
9ff05123
RK		 1284 if (unlikely(err))
1285 return err;
1286
1287 for (i = 0; i < nadd; i++) {
1288 /* extend segment info */
1289 err = -ENOMEM;
1290 segbuf = nilfs_segbuf_new(sci->sc_super);
1291 if (unlikely(!segbuf))
1292 goto failed;
1293
1294 /* map this buffer to region of segment on-disk */
cece5520 1295 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
9ff05123
RK		 1296 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1297
1298 /* allocate the next next full segment */
1299 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1300 if (unlikely(err))
1301 goto failed_segbuf;
1302
1303 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1304 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1305
1306 list_add_tail(&segbuf->sb_list, &list);
1307 prev = segbuf;
1308 }
0935db74 1309 list_splice_tail(&list, &sci->sc_segbufs);
9ff05123
RK		 1310 return 0;
1311
1312 failed_segbuf:
1313 nilfs_segbuf_free(segbuf);
1314 failed:
e29df395 1315 list_for_each_entry(segbuf, &list, sb_list) {
9ff05123 1316 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1317 WARN_ON(ret); /* never fails */
9ff05123 1318 }
e29df395 1319 nilfs_destroy_logs(&list);
9ff05123
RK		 1320 return err;
1321}
1322
a694291a
RK		 1323static void nilfs_free_incomplete_logs(struct list_head *logs,
1324 struct the_nilfs *nilfs)
9ff05123 1325{
a694291a
RK		 1326 struct nilfs_segment_buffer *segbuf, *prev;
1327 struct inode *sufile = nilfs->ns_sufile;
9284ad2a 1328 int ret;
9ff05123 1329
a694291a 1330 segbuf = NILFS_FIRST_SEGBUF(logs);
9ff05123 1331 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
a694291a 1332 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1333 WARN_ON(ret); /* never fails */
9ff05123 1334 }
9284ad2a 1335 if (atomic_read(&segbuf->sb_err)) {
9ff05123
RK		 1336 /* Case 1: The first segment failed */
1337 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1338 /* Case 1a: Partial segment appended into an existing
1339 segment */
1340 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1341 segbuf->sb_fseg_end);
1342 else /* Case 1b: New full segment */
1343 set_nilfs_discontinued(nilfs);
9ff05123
RK		 1344 }
1345
a694291a
RK		 1346 prev = segbuf;
1347 list_for_each_entry_continue(segbuf, logs, sb_list) {
1348 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1349 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1350 WARN_ON(ret); /* never fails */
1351 }
9284ad2a
RK		 1352 if (atomic_read(&segbuf->sb_err) &&
1353 segbuf->sb_segnum != nilfs->ns_nextnum)
1354 /* Case 2: extended segment (!= next) failed */
a694291a
RK		 1355 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1356 prev = segbuf;
9ff05123 1357 }
9ff05123
RK		 1358}
1359
1360static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1361 struct inode *sufile)
1362{
1363 struct nilfs_segment_buffer *segbuf;
9ff05123
RK		 1364 unsigned long live_blocks;
1365 int ret;
1366
1367 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
9ff05123
RK		 1368 live_blocks = segbuf->sb_sum.nblocks +
1369 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
071ec54d
RK		 1370 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1371 live_blocks,
1372 sci->sc_seg_ctime);
1373 WARN_ON(ret); /* always succeed because the segusage is dirty */
9ff05123
RK		 1374 }
1375}
1376
a694291a 1377static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
9ff05123
RK		 1378{
1379 struct nilfs_segment_buffer *segbuf;
9ff05123
RK		 1380 int ret;
1381
a694291a 1382 segbuf = NILFS_FIRST_SEGBUF(logs);
071ec54d
RK		 1383 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1384 segbuf->sb_pseg_start -
1385 segbuf->sb_fseg_start, 0);
1386 WARN_ON(ret); /* always succeed because the segusage is dirty */
9ff05123 1387
a694291a 1388 list_for_each_entry_continue(segbuf, logs, sb_list) {
071ec54d
RK		 1389 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1390 0, 0);
1f5abe7e 1391 WARN_ON(ret); /* always succeed */
9ff05123
RK		 1392 }
1393}
1394
1395static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1396 struct nilfs_segment_buffer *last,
1397 struct inode *sufile)
1398{
e29df395 1399 struct nilfs_segment_buffer *segbuf = last;
9ff05123
RK		 1400 int ret;
1401
e29df395 1402 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
9ff05123
RK		 1403 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1404 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1405 WARN_ON(ret);
9ff05123 1406 }
e29df395 1407 nilfs_truncate_logs(&sci->sc_segbufs, last);
9ff05123
RK		 1408}
1409
1410
1411static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1412 struct the_nilfs *nilfs, int mode)
1413{
1414 struct nilfs_cstage prev_stage = sci->sc_stage;
1415 int err, nadd = 1;
1416
1417 /* Collection retry loop */
1418 for (;;) {
9ff05123
RK		 1419 sci->sc_nblk_this_inc = 0;
1420 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1421
1422 err = nilfs_segctor_reset_segment_buffer(sci);
1423 if (unlikely(err))
1424 goto failed;
1425
1426 err = nilfs_segctor_collect_blocks(sci, mode);
1427 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1428 if (!err)
1429 break;
1430
1431 if (unlikely(err != -E2BIG))
1432 goto failed;
1433
1434 /* The current segment is filled up */
1435 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE)
1436 break;
1437
2d8428ac
RK		 1438 nilfs_clear_logs(&sci->sc_segbufs);
1439
1440 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1441 if (unlikely(err))
1442 return err;
1443
071cb4b8
RK		 1444 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1445 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1446 sci->sc_freesegs,
1447 sci->sc_nfreesegs,
1448 NULL);
1449 WARN_ON(err); /* do not happen */
1450 }
9ff05123
RK		 1451 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1452 sci->sc_stage = prev_stage;
1453 }
1454 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1455 return 0;
1456
1457 failed:
1458 return err;
1459}
1460
1461static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1462 struct buffer_head *new_bh)
1463{
1464 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1465
1466 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1467 /* The caller must release old_bh */
1468}
1469
1470static int
1471nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1472 struct nilfs_segment_buffer *segbuf,
1473 int mode)
1474{
1475 struct inode *inode = NULL;
1476 sector_t blocknr;
1477 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1478 unsigned long nblocks = 0, ndatablk = 0;
1479 struct nilfs_sc_operations *sc_op = NULL;
1480 struct nilfs_segsum_pointer ssp;
1481 struct nilfs_finfo *finfo = NULL;
1482 union nilfs_binfo binfo;
1483 struct buffer_head *bh, *bh_org;
1484 ino_t ino = 0;
1485 int err = 0;
1486
1487 if (!nfinfo)
1488 goto out;
1489
1490 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1491 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1492 ssp.offset = sizeof(struct nilfs_segment_summary);
1493
1494 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1e2b68bf 1495 if (bh == segbuf->sb_super_root)
9ff05123
RK		 1496 break;
1497 if (!finfo) {
1498 finfo = nilfs_segctor_map_segsum_entry(
1499 sci, &ssp, sizeof(*finfo));
1500 ino = le64_to_cpu(finfo->fi_ino);
1501 nblocks = le32_to_cpu(finfo->fi_nblocks);
1502 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1503
1504 if (buffer_nilfs_node(bh))
1505 inode = NILFS_BTNC_I(bh->b_page->mapping);
1506 else
1507 inode = NILFS_AS_I(bh->b_page->mapping);
1508
1509 if (mode == SC_LSEG_DSYNC)
1510 sc_op = &nilfs_sc_dsync_ops;
1511 else if (ino == NILFS_DAT_INO)
1512 sc_op = &nilfs_sc_dat_ops;
1513 else /* file blocks */
1514 sc_op = &nilfs_sc_file_ops;
1515 }
1516 bh_org = bh;
1517 get_bh(bh_org);
1518 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1519 &binfo);
1520 if (bh != bh_org)
1521 nilfs_list_replace_buffer(bh_org, bh);
1522 brelse(bh_org);
1523 if (unlikely(err))
1524 goto failed_bmap;
1525
1526 if (ndatablk > 0)
1527 sc_op->write_data_binfo(sci, &ssp, &binfo);
1528 else
1529 sc_op->write_node_binfo(sci, &ssp, &binfo);
1530
1531 blocknr++;
1532 if (--nblocks == 0) {
1533 finfo = NULL;
1534 if (--nfinfo == 0)
1535 break;
1536 } else if (ndatablk > 0)
1537 ndatablk--;
1538 }
1539 out:
1540 return 0;
1541
1542 failed_bmap:
9ff05123
RK		 1543 return err;
1544}
1545
1546static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1547{
1548 struct nilfs_segment_buffer *segbuf;
1549 int err;
1550
1551 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1552 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1553 if (unlikely(err))
1554 return err;
1555 nilfs_segbuf_fill_in_segsum(segbuf);
1556 }
1557 return 0;
1558}
1559
1560static int
1561nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out)
1562{
1563 struct page *clone_page;
1564 struct buffer_head *bh, *head, *bh2;
1565 void *kaddr;
1566
1567 bh = head = page_buffers(page);
1568
1569 clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0);
1570 if (unlikely(!clone_page))
1571 return -ENOMEM;
1572
1573 bh2 = page_buffers(clone_page);
1574 kaddr = kmap_atomic(page, KM_USER0);
1575 do {
1576 if (list_empty(&bh->b_assoc_buffers))
1577 continue;
1578 get_bh(bh2);
1579 page_cache_get(clone_page); /* for each bh */
1580 memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size);
1581 bh2->b_blocknr = bh->b_blocknr;
1582 list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers);
1583 list_add_tail(&bh->b_assoc_buffers, out);
1584 } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head);
1585 kunmap_atomic(kaddr, KM_USER0);
1586
1587 if (!TestSetPageWriteback(clone_page))
f629d1c9 1588 account_page_writeback(clone_page);
9ff05123
RK		 1589 unlock_page(clone_page);
1590
1591 return 0;
1592}
1593
1594static int nilfs_test_page_to_be_frozen(struct page *page)
1595{
1596 struct address_space *mapping = page->mapping;
1597
1598 if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode))
1599 return 0;
1600
1601 if (page_mapped(page)) {
1602 ClearPageChecked(page);
1603 return 1;
1604 }
1605 return PageChecked(page);
1606}
1607
1608static int nilfs_begin_page_io(struct page *page, struct list_head *out)
1609{
1610 if (!page || PageWriteback(page))
1611 /* For split b-tree node pages, this function may be called
1612 twice. We ignore the 2nd or later calls by this check. */
1613 return 0;
1614
1615 lock_page(page);
1616 clear_page_dirty_for_io(page);
1617 set_page_writeback(page);
1618 unlock_page(page);
1619
1620 if (nilfs_test_page_to_be_frozen(page)) {
1621 int err = nilfs_copy_replace_page_buffers(page, out);
1622 if (unlikely(err))
1623 return err;
1624 }
1625 return 0;
1626}
1627
1628static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci,
1629 struct page **failed_page)
1630{
1631 struct nilfs_segment_buffer *segbuf;
1632 struct page *bd_page = NULL, *fs_page = NULL;
1633 struct list_head *list = &sci->sc_copied_buffers;
1634 int err;
1635
1636 *failed_page = NULL;
1637 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1638 struct buffer_head *bh;
1639
1640 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1641 b_assoc_buffers) {
1642 if (bh->b_page != bd_page) {
1643 if (bd_page) {
1644 lock_page(bd_page);
1645 clear_page_dirty_for_io(bd_page);
1646 set_page_writeback(bd_page);
1647 unlock_page(bd_page);
1648 }
1649 bd_page = bh->b_page;
1650 }
1651 }
1652
1653 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1654 b_assoc_buffers) {
1e2b68bf 1655 if (bh == segbuf->sb_super_root) {
9ff05123
RK		 1656 if (bh->b_page != bd_page) {
1657 lock_page(bd_page);
1658 clear_page_dirty_for_io(bd_page);
1659 set_page_writeback(bd_page);
1660 unlock_page(bd_page);
1661 bd_page = bh->b_page;
1662 }
1663 break;
1664 }
1665 if (bh->b_page != fs_page) {
1666 err = nilfs_begin_page_io(fs_page, list);
1667 if (unlikely(err)) {
1668 *failed_page = fs_page;
1669 goto out;
1670 }
1671 fs_page = bh->b_page;
1672 }
1673 }
1674 }
1675 if (bd_page) {
1676 lock_page(bd_page);
1677 clear_page_dirty_for_io(bd_page);
1678 set_page_writeback(bd_page);
1679 unlock_page(bd_page);
1680 }
1681 err = nilfs_begin_page_io(fs_page, list);
1682 if (unlikely(err))
1683 *failed_page = fs_page;
1684 out:
1685 return err;
1686}
1687
1688static int nilfs_segctor_write(struct nilfs_sc_info *sci,
9c965bac 1689 struct the_nilfs *nilfs)
9ff05123 1690{
d1c6b72a 1691 int ret;
9ff05123 1692
d1c6b72a 1693 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
a694291a
RK		 1694 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1695 return ret;
9ff05123
RK		 1696}
1697
9ff05123
RK		 1698static void __nilfs_end_page_io(struct page *page, int err)
1699{
9ff05123
RK		 1700 if (!err) {
1701 if (!nilfs_page_buffers_clean(page))
1702 __set_page_dirty_nobuffers(page);
1703 ClearPageError(page);
1704 } else {
1705 __set_page_dirty_nobuffers(page);
1706 SetPageError(page);
1707 }
1708
1709 if (buffer_nilfs_allocated(page_buffers(page))) {
1710 if (TestClearPageWriteback(page))
1711 dec_zone_page_state(page, NR_WRITEBACK);
1712 } else
1713 end_page_writeback(page);
1714}
1715
1716static void nilfs_end_page_io(struct page *page, int err)
1717{
1718 if (!page)
1719 return;
1720
a9777845 1721 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
8227b297
RK		 1722 /*
1723 * For b-tree node pages, this function may be called twice
1724 * or more because they might be split in a segment.
1725 */
a9777845
RK		 1726 if (PageDirty(page)) {
1727 /*
1728 * For pages holding split b-tree node buffers, dirty
1729 * flag on the buffers may be cleared discretely.
1730 * In that case, the page is once redirtied for
1731 * remaining buffers, and it must be cancelled if
1732 * all the buffers get cleaned later.
1733 */
1734 lock_page(page);
1735 if (nilfs_page_buffers_clean(page))
1736 __nilfs_clear_page_dirty(page);
1737 unlock_page(page);
1738 }
9ff05123 1739 return;
a9777845 1740 }
9ff05123
RK		 1741
1742 __nilfs_end_page_io(page, err);
1743}
1744
1745static void nilfs_clear_copied_buffers(struct list_head *list, int err)
1746{
1747 struct buffer_head *bh, *head;
1748 struct page *page;
1749
1750 while (!list_empty(list)) {
1751 bh = list_entry(list->next, struct buffer_head,
1752 b_assoc_buffers);
1753 page = bh->b_page;
1754 page_cache_get(page);
1755 head = bh = page_buffers(page);
1756 do {
1757 if (!list_empty(&bh->b_assoc_buffers)) {
1758 list_del_init(&bh->b_assoc_buffers);
1759 if (!err) {
1760 set_buffer_uptodate(bh);
1761 clear_buffer_dirty(bh);
27e6c7a3 1762 clear_buffer_delay(bh);
9ff05123
RK		 1763 clear_buffer_nilfs_volatile(bh);
1764 }
1765 brelse(bh); /* for b_assoc_buffers */
1766 }
1767 } while ((bh = bh->b_this_page) != head);
1768
1769 __nilfs_end_page_io(page, err);
1770 page_cache_release(page);
1771 }
1772}
1773
a694291a 1774static void nilfs_abort_logs(struct list_head *logs, struct page *failed_page,
1e2b68bf 1775 int err)
9ff05123
RK		 1776{
1777 struct nilfs_segment_buffer *segbuf;
1778 struct page *bd_page = NULL, *fs_page = NULL;
a694291a 1779 struct buffer_head *bh;
9ff05123 1780
a694291a
RK		 1781 if (list_empty(logs))
1782 return;
9ff05123 1783
a694291a 1784 list_for_each_entry(segbuf, logs, sb_list) {
9ff05123
RK		 1785 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1786 b_assoc_buffers) {
1787 if (bh->b_page != bd_page) {
1788 if (bd_page)
1789 end_page_writeback(bd_page);
1790 bd_page = bh->b_page;
1791 }
1792 }
1793
1794 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1795 b_assoc_buffers) {
1e2b68bf 1796 if (bh == segbuf->sb_super_root) {
9ff05123
RK		 1797 if (bh->b_page != bd_page) {
1798 end_page_writeback(bd_page);
1799 bd_page = bh->b_page;
1800 }
1801 break;
1802 }
1803 if (bh->b_page != fs_page) {
1804 nilfs_end_page_io(fs_page, err);
8227b297 1805 if (fs_page && fs_page == failed_page)
a694291a 1806 return;
9ff05123
RK		 1807 fs_page = bh->b_page;
1808 }
1809 }
1810 }
1811 if (bd_page)
1812 end_page_writeback(bd_page);
1813
1814 nilfs_end_page_io(fs_page, err);
a694291a
RK		 1815}
1816
1817static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1818 struct the_nilfs *nilfs, int err)
1819{
1820 LIST_HEAD(logs);
1821 int ret;
1822
1823 list_splice_tail_init(&sci->sc_write_logs, &logs);
1824 ret = nilfs_wait_on_logs(&logs);
1e2b68bf 1825 nilfs_abort_logs(&logs, NULL, ret ? : err);
a694291a
RK		 1826
1827 list_splice_tail_init(&sci->sc_segbufs, &logs);
1828 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1829 nilfs_free_incomplete_logs(&logs, nilfs);
9ff05123 1830 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err);
a694291a
RK		 1831
1832 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1833 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1834 sci->sc_freesegs,
1835 sci->sc_nfreesegs,
1836 NULL);
1837 WARN_ON(ret); /* do not happen */
1838 }
1839
1840 nilfs_destroy_logs(&logs);
9ff05123
RK		 1841}
1842
1843static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1844 struct nilfs_segment_buffer *segbuf)
1845{
1846 nilfs->ns_segnum = segbuf->sb_segnum;
1847 nilfs->ns_nextnum = segbuf->sb_nextnum;
1848 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1849 + segbuf->sb_sum.nblocks;
1850 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1851 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1852}
1853
1854static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1855{
1856 struct nilfs_segment_buffer *segbuf;
1857 struct page *bd_page = NULL, *fs_page = NULL;
d96bbfa2 1858 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
1e2b68bf 1859 int update_sr = false;
9ff05123 1860
a694291a 1861 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
9ff05123
RK		 1862 struct buffer_head *bh;
1863
1864 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1865 b_assoc_buffers) {
1866 set_buffer_uptodate(bh);
1867 clear_buffer_dirty(bh);
1868 if (bh->b_page != bd_page) {
1869 if (bd_page)
1870 end_page_writeback(bd_page);
1871 bd_page = bh->b_page;
1872 }
1873 }
1874 /*
1875 * We assume that the buffers which belong to the same page
1876 * continue over the buffer list.
1877 * Under this assumption, the last BHs of pages is
1878 * identifiable by the discontinuity of bh->b_page
1879 * (page != fs_page).
1880 *
1881 * For B-tree node blocks, however, this assumption is not
1882 * guaranteed. The cleanup code of B-tree node pages needs
1883 * special care.
1884 */
1885 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1886 b_assoc_buffers) {
1887 set_buffer_uptodate(bh);
1888 clear_buffer_dirty(bh);
27e6c7a3 1889 clear_buffer_delay(bh);
9ff05123 1890 clear_buffer_nilfs_volatile(bh);
b1f6a4f2 1891 clear_buffer_nilfs_redirected(bh);
1e2b68bf 1892 if (bh == segbuf->sb_super_root) {
9ff05123
RK		 1893 if (bh->b_page != bd_page) {
1894 end_page_writeback(bd_page);
1895 bd_page = bh->b_page;
1896 }
1e2b68bf 1897 update_sr = true;
9ff05123
RK		 1898 break;
1899 }
1900 if (bh->b_page != fs_page) {
1901 nilfs_end_page_io(fs_page, 0);
1902 fs_page = bh->b_page;
1903 }
1904 }
1905
4762077c
RK		 1906 if (!nilfs_segbuf_simplex(segbuf)) {
1907 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
9ff05123
RK		 1908 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1909 sci->sc_lseg_stime = jiffies;
1910 }
4762077c 1911 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
9ff05123
RK		 1912 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1913 }
1914 }
1915 /*
1916 * Since pages may continue over multiple segment buffers,
1917 * end of the last page must be checked outside of the loop.
1918 */
1919 if (bd_page)
1920 end_page_writeback(bd_page);
1921
1922 nilfs_end_page_io(fs_page, 0);
1923
1924 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0);
1925
1926 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1927
c1c1d709 1928 if (nilfs_doing_gc())
9ff05123 1929 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
c1c1d709 1930 else
9ff05123 1931 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
9ff05123
RK		 1932
1933 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1934
a694291a 1935 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
9ff05123
RK		 1936 nilfs_set_next_segment(nilfs, segbuf);
1937
1938 if (update_sr) {
1939 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
e339ad31 1940 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
9ff05123 1941
c96fa464 1942 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
9ff05123
RK		 1943 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1944 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
a694291a 1945 nilfs_segctor_clear_metadata_dirty(sci);
9ff05123
RK		 1946 } else
1947 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1948}
1949
a694291a
RK		 1950static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1951{
1952 int ret;
1953
1954 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1955 if (!ret) {
1956 nilfs_segctor_complete_write(sci);
1957 nilfs_destroy_logs(&sci->sc_write_logs);
1958 }
1959 return ret;
1960}
1961
693dd321
RK		 1962static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1963 struct the_nilfs *nilfs)
9ff05123
RK		 1964{
1965 struct nilfs_inode_info *ii, *n;
e912a5b6 1966 struct inode *ifile = sci->sc_root->ifile;
9ff05123 1967
693dd321 1968 spin_lock(&nilfs->ns_inode_lock);
9ff05123 1969 retry:
693dd321 1970 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
9ff05123
RK		 1971 if (!ii->i_bh) {
1972 struct buffer_head *ibh;
1973 int err;
1974
693dd321 1975 spin_unlock(&nilfs->ns_inode_lock);
9ff05123 1976 err = nilfs_ifile_get_inode_block(
e912a5b6 1977 ifile, ii->vfs_inode.i_ino, &ibh);
9ff05123 1978 if (unlikely(err)) {
693dd321 1979 nilfs_warning(sci->sc_super, __func__,
9ff05123
RK		 1980 "failed to get inode block.\n");
1981 return err;
1982 }
1983 nilfs_mdt_mark_buffer_dirty(ibh);
e912a5b6 1984 nilfs_mdt_mark_dirty(ifile);
693dd321 1985 spin_lock(&nilfs->ns_inode_lock);
9ff05123
RK		 1986 if (likely(!ii->i_bh))
1987 ii->i_bh = ibh;
1988 else
1989 brelse(ibh);
1990 goto retry;
1991 }
9ff05123
RK		 1992
1993 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1994 set_bit(NILFS_I_BUSY, &ii->i_state);
1995 list_del(&ii->i_dirty);
1996 list_add_tail(&ii->i_dirty, &sci->sc_dirty_files);
1997 }
693dd321 1998 spin_unlock(&nilfs->ns_inode_lock);
9ff05123 1999
9ff05123
RK		 2000 return 0;
2001}
2002
693dd321
RK		 2003static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
2004 struct the_nilfs *nilfs)
9ff05123
RK		 2005{
2006 struct nilfs_transaction_info *ti = current->journal_info;
2007 struct nilfs_inode_info *ii, *n;
9ff05123 2008
693dd321 2009 spin_lock(&nilfs->ns_inode_lock);
9ff05123
RK		 2010 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2011 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
6c43f410 2012 test_bit(NILFS_I_DIRTY, &ii->i_state))
9ff05123 2013 continue;
6c43f410 2014
9ff05123
RK		 2015 clear_bit(NILFS_I_BUSY, &ii->i_state);
2016 brelse(ii->i_bh);
2017 ii->i_bh = NULL;
2018 list_del(&ii->i_dirty);
2019 list_add_tail(&ii->i_dirty, &ti->ti_garbage);
2020 }
693dd321 2021 spin_unlock(&nilfs->ns_inode_lock);
9ff05123
RK		 2022}
2023
9ff05123
RK		 2024/*
2025 * Main procedure of segment constructor
2026 */
2027static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2028{
d96bbfa2 2029 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123 2030 struct page *failed_page;
1e2b68bf 2031 int err;
9ff05123
RK		 2032
2033 sci->sc_stage.scnt = NILFS_ST_INIT;
6c43f410 2034 sci->sc_cno = nilfs->ns_cno;
9ff05123 2035
693dd321 2036 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
9ff05123
RK		 2037 if (unlikely(err))
2038 goto out;
2039
e912a5b6 2040 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
9ff05123
RK		 2041 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2042
2043 if (nilfs_segctor_clean(sci))
2044 goto out;
2045
2046 do {
2047 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2048
2049 err = nilfs_segctor_begin_construction(sci, nilfs);
2050 if (unlikely(err))
2051 goto out;
2052
2053 /* Update time stamp */
2054 sci->sc_seg_ctime = get_seconds();
2055
2056 err = nilfs_segctor_collect(sci, nilfs, mode);
2057 if (unlikely(err))
2058 goto failed;
2059
9ff05123
RK		 2060 /* Avoid empty segment */
2061 if (sci->sc_stage.scnt == NILFS_ST_DONE &&
4762077c 2062 nilfs_segbuf_empty(sci->sc_curseg)) {
a694291a 2063 nilfs_segctor_abort_construction(sci, nilfs, 1);
9ff05123
RK		 2064 goto out;
2065 }
2066
2067 err = nilfs_segctor_assign(sci, mode);
2068 if (unlikely(err))
2069 goto failed;
2070
9ff05123 2071 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
e912a5b6 2072 nilfs_segctor_fill_in_file_bmap(sci);
9ff05123 2073
1e2b68bf
RK		 2074 if (mode == SC_LSEG_SR &&
2075 sci->sc_stage.scnt >= NILFS_ST_CPFILE) {
9ff05123
RK		 2076 err = nilfs_segctor_fill_in_checkpoint(sci);
2077 if (unlikely(err))
a694291a 2078 goto failed_to_write;
9ff05123
RK		 2079
2080 nilfs_segctor_fill_in_super_root(sci, nilfs);
2081 }
2082 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2083
2084 /* Write partial segments */
2085 err = nilfs_segctor_prepare_write(sci, &failed_page);
a694291a 2086 if (err) {
1e2b68bf 2087 nilfs_abort_logs(&sci->sc_segbufs, failed_page, err);
9ff05123 2088 goto failed_to_write;
a694291a 2089 }
aaed1d5b
RK		 2090
2091 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2092 nilfs->ns_crc_seed);
9ff05123 2093
9c965bac 2094 err = nilfs_segctor_write(sci, nilfs);
9ff05123
RK		 2095 if (unlikely(err))
2096 goto failed_to_write;
2097
a694291a
RK		 2098 if (sci->sc_stage.scnt == NILFS_ST_DONE ||
2099 nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) {
2100 /*
2101 * At this point, we avoid double buffering
2102 * for blocksize < pagesize because page dirty
2103 * flag is turned off during write and dirty
2104 * buffers are not properly collected for
2105 * pages crossing over segments.
2106 */
2107 err = nilfs_segctor_wait(sci);
2108 if (err)
2109 goto failed_to_write;
2110 }
9ff05123
RK		 2111 } while (sci->sc_stage.scnt != NILFS_ST_DONE);
2112
9ff05123 2113 out:
693dd321 2114 nilfs_segctor_drop_written_files(sci, nilfs);
9ff05123
RK		 2115 return err;
2116
2117 failed_to_write:
9ff05123
RK		 2118 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2119 nilfs_redirty_inodes(&sci->sc_dirty_files);
9ff05123
RK		 2120
2121 failed:
2122 if (nilfs_doing_gc())
2123 nilfs_redirty_inodes(&sci->sc_gc_inodes);
a694291a 2124 nilfs_segctor_abort_construction(sci, nilfs, err);
9ff05123
RK		 2125 goto out;
2126}
2127
2128/**
9ccf56c1 2129 * nilfs_segctor_start_timer - set timer of background write
9ff05123
RK		 2130 * @sci: nilfs_sc_info
2131 *
2132 * If the timer has already been set, it ignores the new request.
2133 * This function MUST be called within a section locking the segment
2134 * semaphore.
2135 */
2136static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2137{
2138 spin_lock(&sci->sc_state_lock);
fdce895e
LH		 2139 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2140 sci->sc_timer.expires = jiffies + sci->sc_interval;
2141 add_timer(&sci->sc_timer);
9ff05123
RK		 2142 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2143 }
2144 spin_unlock(&sci->sc_state_lock);
2145}
2146
2147static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2148{
2149 spin_lock(&sci->sc_state_lock);
2150 if (!(sci->sc_flush_request & (1 << bn))) {
2151 unsigned long prev_req = sci->sc_flush_request;
2152
2153 sci->sc_flush_request |= (1 << bn);
2154 if (!prev_req)
2155 wake_up(&sci->sc_wait_daemon);
2156 }
2157 spin_unlock(&sci->sc_state_lock);
2158}
2159
2160/**
2161 * nilfs_flush_segment - trigger a segment construction for resource control
2162 * @sb: super block
2163 * @ino: inode number of the file to be flushed out.
2164 */
2165void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2166{
3fd3fe5a
RK		 2167 struct the_nilfs *nilfs = NILFS_SB(sb)->s_nilfs;
2168 struct nilfs_sc_info *sci = nilfs->ns_writer;
9ff05123
RK		 2169
2170 if (!sci || nilfs_doing_construction())
2171 return;
2172 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2173 /* assign bit 0 to data files */
2174}
2175
9ff05123
RK		 2176struct nilfs_segctor_wait_request {
2177 wait_queue_t wq;
2178 __u32 seq;
2179 int err;
2180 atomic_t done;
2181};
2182
2183static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2184{
2185 struct nilfs_segctor_wait_request wait_req;
2186 int err = 0;
2187
2188 spin_lock(&sci->sc_state_lock);
2189 init_wait(&wait_req.wq);
2190 wait_req.err = 0;
2191 atomic_set(&wait_req.done, 0);
2192 wait_req.seq = ++sci->sc_seq_request;
2193 spin_unlock(&sci->sc_state_lock);
2194
2195 init_waitqueue_entry(&wait_req.wq, current);
2196 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2197 set_current_state(TASK_INTERRUPTIBLE);
2198 wake_up(&sci->sc_wait_daemon);
2199
2200 for (;;) {
2201 if (atomic_read(&wait_req.done)) {
2202 err = wait_req.err;
2203 break;
2204 }
2205 if (!signal_pending(current)) {
2206 schedule();
2207 continue;
2208 }
2209 err = -ERESTARTSYS;
2210 break;
2211 }
2212 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2213 return err;
2214}
2215
2216static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2217{
2218 struct nilfs_segctor_wait_request *wrq, *n;
2219 unsigned long flags;
2220
2221 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2222 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2223 wq.task_list) {
2224 if (!atomic_read(&wrq->done) &&
2225 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2226 wrq->err = err;
2227 atomic_set(&wrq->done, 1);
2228 }
2229 if (atomic_read(&wrq->done)) {
2230 wrq->wq.func(&wrq->wq,
2231 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2232 0, NULL);
2233 }
2234 }
2235 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2236}
2237
2238/**
2239 * nilfs_construct_segment - construct a logical segment
2240 * @sb: super block
2241 *
2242 * Return Value: On success, 0 is retured. On errors, one of the following
2243 * negative error code is returned.
2244 *
2245 * %-EROFS - Read only filesystem.
2246 *
2247 * %-EIO - I/O error
2248 *
2249 * %-ENOSPC - No space left on device (only in a panic state).
2250 *
2251 * %-ERESTARTSYS - Interrupted.
2252 *
2253 * %-ENOMEM - Insufficient memory available.
2254 */
2255int nilfs_construct_segment(struct super_block *sb)
2256{
3fd3fe5a
RK		 2257 struct the_nilfs *nilfs = NILFS_SB(sb)->s_nilfs;
2258 struct nilfs_sc_info *sci = nilfs->ns_writer;
9ff05123
RK		 2259 struct nilfs_transaction_info *ti;
2260 int err;
2261
2262 if (!sci)
2263 return -EROFS;
2264
2265 /* A call inside transactions causes a deadlock. */
2266 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2267
2268 err = nilfs_segctor_sync(sci);
2269 return err;
2270}
2271
2272/**
2273 * nilfs_construct_dsync_segment - construct a data-only logical segment
2274 * @sb: super block
f30bf3e4
RK		 2275 * @inode: inode whose data blocks should be written out
2276 * @start: start byte offset
2277 * @end: end byte offset (inclusive)
9ff05123
RK		 2278 *
2279 * Return Value: On success, 0 is retured. On errors, one of the following
2280 * negative error code is returned.
2281 *
2282 * %-EROFS - Read only filesystem.
2283 *
2284 * %-EIO - I/O error
2285 *
2286 * %-ENOSPC - No space left on device (only in a panic state).
2287 *
2288 * %-ERESTARTSYS - Interrupted.
2289 *
2290 * %-ENOMEM - Insufficient memory available.
2291 */
f30bf3e4
RK		 2292int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2293 loff_t start, loff_t end)
9ff05123
RK		 2294{
2295 struct nilfs_sb_info *sbi = NILFS_SB(sb);
3b2ce58b 2296 struct the_nilfs *nilfs = sbi->s_nilfs;
3fd3fe5a 2297 struct nilfs_sc_info *sci = nilfs->ns_writer;
9ff05123
RK		 2298 struct nilfs_inode_info *ii;
2299 struct nilfs_transaction_info ti;
2300 int err = 0;
2301
2302 if (!sci)
2303 return -EROFS;
2304
2305 nilfs_transaction_lock(sbi, &ti, 0);
2306
2307 ii = NILFS_I(inode);
2308 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) ||
3b2ce58b 2309 nilfs_test_opt(nilfs, STRICT_ORDER) ||
9ff05123 2310 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
3b2ce58b 2311 nilfs_discontinued(nilfs)) {
9ff05123
RK		 2312 nilfs_transaction_unlock(sbi);
2313 err = nilfs_segctor_sync(sci);
2314 return err;
2315 }
2316
693dd321 2317 spin_lock(&nilfs->ns_inode_lock);
9ff05123
RK		 2318 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2319 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
693dd321 2320 spin_unlock(&nilfs->ns_inode_lock);
9ff05123
RK		 2321 nilfs_transaction_unlock(sbi);
2322 return 0;
2323 }
693dd321 2324 spin_unlock(&nilfs->ns_inode_lock);
f30bf3e4
RK		 2325 sci->sc_dsync_inode = ii;
2326 sci->sc_dsync_start = start;
2327 sci->sc_dsync_end = end;
9ff05123
RK		 2328
2329 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2330
2331 nilfs_transaction_unlock(sbi);
2332 return err;
2333}
2334
9ff05123
RK		 2335#define FLUSH_FILE_BIT (0x1) /* data file only */
2336#define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2337
dcd76186
RK		 2338/**
2339 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2340 * @sci: segment constructor object
2341 */
2342static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
9ff05123 2343{
9ff05123 2344 spin_lock(&sci->sc_state_lock);
dcd76186 2345 sci->sc_seq_accepted = sci->sc_seq_request;
9ff05123 2346 spin_unlock(&sci->sc_state_lock);
fdce895e 2347 del_timer_sync(&sci->sc_timer);
9ff05123
RK		 2348}
2349
dcd76186
RK		 2350/**
2351 * nilfs_segctor_notify - notify the result of request to caller threads
2352 * @sci: segment constructor object
2353 * @mode: mode of log forming
2354 * @err: error code to be notified
2355 */
2356static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
9ff05123
RK		 2357{
2358 /* Clear requests (even when the construction failed) */
2359 spin_lock(&sci->sc_state_lock);
2360
dcd76186 2361 if (mode == SC_LSEG_SR) {
aeda7f63 2362 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
dcd76186
RK		 2363 sci->sc_seq_done = sci->sc_seq_accepted;
2364 nilfs_segctor_wakeup(sci, err);
9ff05123 2365 sci->sc_flush_request = 0;
aeda7f63 2366 } else {
dcd76186 2367 if (mode == SC_FLUSH_FILE)
aeda7f63 2368 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
dcd76186 2369 else if (mode == SC_FLUSH_DAT)
aeda7f63
RK		 2370 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2371
2372 /* re-enable timer if checkpoint creation was not done */
fdce895e
LH		 2373 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2374 time_before(jiffies, sci->sc_timer.expires))
2375 add_timer(&sci->sc_timer);
aeda7f63 2376 }
9ff05123
RK		 2377 spin_unlock(&sci->sc_state_lock);
2378}
2379
dcd76186
RK		 2380/**
2381 * nilfs_segctor_construct - form logs and write them to disk
2382 * @sci: segment constructor object
2383 * @mode: mode of log forming
2384 */
2385static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
9ff05123 2386{
d96bbfa2 2387 struct nilfs_sb_info *sbi = NILFS_SB(sci->sc_super);
9ff05123 2388 struct the_nilfs *nilfs = sbi->s_nilfs;
d26493b6 2389 struct nilfs_super_block **sbp;
9ff05123
RK		 2390 int err = 0;
2391
dcd76186
RK		 2392 nilfs_segctor_accept(sci);
2393
9ff05123 2394 if (nilfs_discontinued(nilfs))
dcd76186
RK		 2395 mode = SC_LSEG_SR;
2396 if (!nilfs_segctor_confirm(sci))
2397 err = nilfs_segctor_do_construct(sci, mode);
2398
9ff05123 2399 if (likely(!err)) {
dcd76186 2400 if (mode != SC_FLUSH_DAT)
9ff05123
RK		 2401 atomic_set(&nilfs->ns_ndirtyblks, 0);
2402 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2403 nilfs_discontinued(nilfs)) {
2404 down_write(&nilfs->ns_sem);
d26493b6 2405 err = -EIO;
b2ac86e1
JS		 2406 sbp = nilfs_prepare_super(sbi,
2407 nilfs_sb_will_flip(nilfs));
2408 if (likely(sbp)) {
2409 nilfs_set_log_cursor(sbp[0], nilfs);
2410 err = nilfs_commit_super(sbi, NILFS_SB_COMMIT);
2411 }
9ff05123
RK		 2412 up_write(&nilfs->ns_sem);
2413 }
2414 }
dcd76186
RK		 2415
2416 nilfs_segctor_notify(sci, mode, err);
9ff05123
RK		 2417 return err;
2418}
2419
2420static void nilfs_construction_timeout(unsigned long data)
2421{
2422 struct task_struct *p = (struct task_struct *)data;
2423 wake_up_process(p);
2424}
2425
2426static void
2427nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2428{
2429 struct nilfs_inode_info *ii, *n;
2430
2431 list_for_each_entry_safe(ii, n, head, i_dirty) {
2432 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2433 continue;
9ff05123 2434 list_del_init(&ii->i_dirty);
263d90ce 2435 iput(&ii->vfs_inode);
9ff05123
RK		 2436 }
2437}
2438
4f6b8288
RK		 2439int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2440 void **kbufs)
9ff05123
RK		 2441{
2442 struct nilfs_sb_info *sbi = NILFS_SB(sb);
9ff05123 2443 struct the_nilfs *nilfs = sbi->s_nilfs;
3fd3fe5a 2444 struct nilfs_sc_info *sci = nilfs->ns_writer;
9ff05123 2445 struct nilfs_transaction_info ti;
9ff05123
RK		 2446 int err;
2447
2448 if (unlikely(!sci))
2449 return -EROFS;
2450
2451 nilfs_transaction_lock(sbi, &ti, 1);
2452
c1c1d709 2453 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
9ff05123
RK		 2454 if (unlikely(err))
2455 goto out_unlock;
071cb4b8 2456
4f6b8288 2457 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
c1c1d709
RK		 2458 if (unlikely(err)) {
2459 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
9ff05123 2460 goto out_unlock;
c1c1d709 2461 }
9ff05123 2462
071cb4b8
RK		 2463 sci->sc_freesegs = kbufs[4];
2464 sci->sc_nfreesegs = argv[4].v_nmembs;
0935db74 2465 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
9ff05123
RK		 2466
2467 for (;;) {
dcd76186 2468 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
9ff05123 2469 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
9ff05123
RK		 2470
2471 if (likely(!err))
2472 break;
2473
2474 nilfs_warning(sb, __func__,
2475 "segment construction failed. (err=%d)", err);
2476 set_current_state(TASK_INTERRUPTIBLE);
2477 schedule_timeout(sci->sc_interval);
2478 }
3b2ce58b 2479 if (nilfs_test_opt(nilfs, DISCARD)) {
e902ec99
JS		 2480 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2481 sci->sc_nfreesegs);
2482 if (ret) {
2483 printk(KERN_WARNING
2484 "NILFS warning: error %d on discard request, "
2485 "turning discards off for the device\n", ret);
3b2ce58b 2486 nilfs_clear_opt(nilfs, DISCARD);
e902ec99
JS		 2487 }
2488 }
9ff05123
RK		 2489
2490 out_unlock:
071cb4b8
RK		 2491 sci->sc_freesegs = NULL;
2492 sci->sc_nfreesegs = 0;
c1c1d709 2493 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
9ff05123
RK		 2494 nilfs_transaction_unlock(sbi);
2495 return err;
2496}
2497
2498static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2499{
d96bbfa2 2500 struct nilfs_sb_info *sbi = NILFS_SB(sci->sc_super);
9ff05123 2501 struct nilfs_transaction_info ti;
9ff05123
RK		 2502
2503 nilfs_transaction_lock(sbi, &ti, 0);
dcd76186 2504 nilfs_segctor_construct(sci, mode);
9ff05123
RK		 2505
2506 /*
2507 * Unclosed segment should be retried. We do this using sc_timer.
2508 * Timeout of sc_timer will invoke complete construction which leads
2509 * to close the current logical segment.
2510 */
2511 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2512 nilfs_segctor_start_timer(sci);
2513
2514 nilfs_transaction_unlock(sbi);
2515}
2516
2517static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2518{
2519 int mode = 0;
2520 int err;
2521
2522 spin_lock(&sci->sc_state_lock);
2523 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2524 SC_FLUSH_DAT : SC_FLUSH_FILE;
2525 spin_unlock(&sci->sc_state_lock);
2526
2527 if (mode) {
2528 err = nilfs_segctor_do_construct(sci, mode);
2529
2530 spin_lock(&sci->sc_state_lock);
2531 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2532 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2533 spin_unlock(&sci->sc_state_lock);
2534 }
2535 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2536}
2537
2538static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2539{
2540 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2541 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2542 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2543 return SC_FLUSH_FILE;
2544 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2545 return SC_FLUSH_DAT;
2546 }
2547 return SC_LSEG_SR;
2548}
2549
2550/**
2551 * nilfs_segctor_thread - main loop of the segment constructor thread.
2552 * @arg: pointer to a struct nilfs_sc_info.
2553 *
2554 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2555 * to execute segment constructions.
2556 */
2557static int nilfs_segctor_thread(void *arg)
2558{
2559 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
d96bbfa2 2560 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123
RK		 2561 int timeout = 0;
2562
fdce895e
LH		 2563 sci->sc_timer.data = (unsigned long)current;
2564 sci->sc_timer.function = nilfs_construction_timeout;
9ff05123
RK		 2565
2566 /* start sync. */
2567 sci->sc_task = current;
2568 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2569 printk(KERN_INFO
2570 "segctord starting. Construction interval = %lu seconds, "
2571 "CP frequency < %lu seconds\n",
2572 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2573
2574 spin_lock(&sci->sc_state_lock);
2575 loop:
2576 for (;;) {
2577 int mode;
2578
2579 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2580 goto end_thread;
2581
2582 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2583 mode = SC_LSEG_SR;
2584 else if (!sci->sc_flush_request)
2585 break;
2586 else
2587 mode = nilfs_segctor_flush_mode(sci);
2588
2589 spin_unlock(&sci->sc_state_lock);
2590 nilfs_segctor_thread_construct(sci, mode);
2591 spin_lock(&sci->sc_state_lock);
2592 timeout = 0;
2593 }
2594
2595
2596 if (freezing(current)) {
2597 spin_unlock(&sci->sc_state_lock);
2598 refrigerator();
2599 spin_lock(&sci->sc_state_lock);
2600 } else {
2601 DEFINE_WAIT(wait);
2602 int should_sleep = 1;
2603
2604 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2605 TASK_INTERRUPTIBLE);
2606
2607 if (sci->sc_seq_request != sci->sc_seq_done)
2608 should_sleep = 0;
2609 else if (sci->sc_flush_request)
2610 should_sleep = 0;
2611 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2612 should_sleep = time_before(jiffies,
fdce895e 2613 sci->sc_timer.expires);
9ff05123
RK		 2614
2615 if (should_sleep) {
2616 spin_unlock(&sci->sc_state_lock);
2617 schedule();
2618 spin_lock(&sci->sc_state_lock);
2619 }
2620 finish_wait(&sci->sc_wait_daemon, &wait);
2621 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
fdce895e 2622 time_after_eq(jiffies, sci->sc_timer.expires));
e605f0a7
RK		 2623
2624 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
1dfa2710 2625 set_nilfs_discontinued(nilfs);
9ff05123
RK		 2626 }
2627 goto loop;
2628
2629 end_thread:
2630 spin_unlock(&sci->sc_state_lock);
9ff05123
RK		 2631
2632 /* end sync. */
2633 sci->sc_task = NULL;
2634 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2635 return 0;
2636}
2637
2638static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2639{
2640 struct task_struct *t;
2641
2642 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2643 if (IS_ERR(t)) {
2644 int err = PTR_ERR(t);
2645
2646 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2647 err);
2648 return err;
2649 }
2650 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2651 return 0;
2652}
2653
2654static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
6b81e14e
JS		 2655 __acquires(&sci->sc_state_lock)
2656 __releases(&sci->sc_state_lock)
9ff05123
RK		 2657{
2658 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2659
2660 while (sci->sc_task) {
2661 wake_up(&sci->sc_wait_daemon);
2662 spin_unlock(&sci->sc_state_lock);
2663 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2664 spin_lock(&sci->sc_state_lock);
2665 }
2666}
2667
9ff05123
RK		 2668/*
2669 * Setup & clean-up functions
2670 */
e912a5b6
RK		 2671static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi,
2672 struct nilfs_root *root)
9ff05123 2673{
574e6c31 2674 struct the_nilfs *nilfs = sbi->s_nilfs;
9ff05123
RK		 2675 struct nilfs_sc_info *sci;
2676
2677 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2678 if (!sci)
2679 return NULL;
2680
9ff05123
RK		 2681 sci->sc_super = sbi->s_super;
2682
e912a5b6
RK		 2683 nilfs_get_root(root);
2684 sci->sc_root = root;
2685
9ff05123
RK		 2686 init_waitqueue_head(&sci->sc_wait_request);
2687 init_waitqueue_head(&sci->sc_wait_daemon);
2688 init_waitqueue_head(&sci->sc_wait_task);
2689 spin_lock_init(&sci->sc_state_lock);
2690 INIT_LIST_HEAD(&sci->sc_dirty_files);
2691 INIT_LIST_HEAD(&sci->sc_segbufs);
a694291a 2692 INIT_LIST_HEAD(&sci->sc_write_logs);
9ff05123 2693 INIT_LIST_HEAD(&sci->sc_gc_inodes);
9ff05123 2694 INIT_LIST_HEAD(&sci->sc_copied_buffers);
fdce895e 2695 init_timer(&sci->sc_timer);
9ff05123
RK		 2696
2697 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2698 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2699 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2700
574e6c31
RK		 2701 if (nilfs->ns_interval)
2702 sci->sc_interval = nilfs->ns_interval;
2703 if (nilfs->ns_watermark)
2704 sci->sc_watermark = nilfs->ns_watermark;
9ff05123
RK		 2705 return sci;
2706}
2707
2708static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2709{
2710 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2711
2712 /* The segctord thread was stopped and its timer was removed.
2713 But some tasks remain. */
2714 do {
d96bbfa2 2715 struct nilfs_sb_info *sbi = NILFS_SB(sci->sc_super);
9ff05123 2716 struct nilfs_transaction_info ti;
9ff05123
RK		 2717
2718 nilfs_transaction_lock(sbi, &ti, 0);
dcd76186 2719 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
9ff05123
RK		 2720 nilfs_transaction_unlock(sbi);
2721
2722 } while (ret && retrycount-- > 0);
2723}
2724
2725/**
2726 * nilfs_segctor_destroy - destroy the segment constructor.
2727 * @sci: nilfs_sc_info
2728 *
2729 * nilfs_segctor_destroy() kills the segctord thread and frees
2730 * the nilfs_sc_info struct.
2731 * Caller must hold the segment semaphore.
2732 */
2733static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2734{
d96bbfa2 2735 struct the_nilfs *nilfs = NILFS_SB(sci->sc_super)->s_nilfs;
9ff05123
RK		 2736 int flag;
2737
693dd321 2738 up_write(&nilfs->ns_segctor_sem);
9ff05123
RK		 2739
2740 spin_lock(&sci->sc_state_lock);
2741 nilfs_segctor_kill_thread(sci);
2742 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2743 || sci->sc_seq_request != sci->sc_seq_done);
2744 spin_unlock(&sci->sc_state_lock);
2745
3256a055 2746 if (flag || !nilfs_segctor_confirm(sci))
9ff05123
RK		 2747 nilfs_segctor_write_out(sci);
2748
1f5abe7e 2749 WARN_ON(!list_empty(&sci->sc_copied_buffers));
9ff05123
RK		 2750
2751 if (!list_empty(&sci->sc_dirty_files)) {
693dd321 2752 nilfs_warning(sci->sc_super, __func__,
9ff05123 2753 "dirty file(s) after the final construction\n");
693dd321 2754 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
9ff05123 2755 }
9ff05123 2756
1f5abe7e 2757 WARN_ON(!list_empty(&sci->sc_segbufs));
a694291a 2758 WARN_ON(!list_empty(&sci->sc_write_logs));
9ff05123 2759
e912a5b6
RK		 2760 nilfs_put_root(sci->sc_root);
2761
693dd321 2762 down_write(&nilfs->ns_segctor_sem);
9ff05123 2763
fdce895e 2764 del_timer_sync(&sci->sc_timer);
9ff05123
RK		 2765 kfree(sci);
2766}
2767
2768/**
2769 * nilfs_attach_segment_constructor - attach a segment constructor
2770 * @sbi: nilfs_sb_info
e912a5b6 2771 * @root: root object of the current filesystem tree
9ff05123
RK		 2772 *
2773 * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info,
7a65004b 2774 * initializes it, and starts the segment constructor.
9ff05123
RK		 2775 *
2776 * Return Value: On success, 0 is returned. On error, one of the following
2777 * negative error code is returned.
2778 *
2779 * %-ENOMEM - Insufficient memory available.
2780 */
e912a5b6
RK		 2781int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi,
2782 struct nilfs_root *root)
9ff05123 2783{
3fd3fe5a 2784 struct the_nilfs *nilfs = sbi->s_nilfs;
9ff05123
RK		 2785 int err;
2786
3fd3fe5a 2787 if (nilfs->ns_writer) {
fe5f171b
RK		 2788 /*
2789 * This happens if the filesystem was remounted
2790 * read/write after nilfs_error degenerated it into a
2791 * read-only mount.
2792 */
2793 nilfs_detach_segment_constructor(sbi);
2794 }
2795
3fd3fe5a
RK		 2796 nilfs->ns_writer = nilfs_segctor_new(sbi, root);
2797 if (!nilfs->ns_writer)
9ff05123
RK		 2798 return -ENOMEM;
2799
3fd3fe5a 2800 err = nilfs_segctor_start_thread(nilfs->ns_writer);
9ff05123 2801 if (err) {
3fd3fe5a
RK		 2802 kfree(nilfs->ns_writer);
2803 nilfs->ns_writer = NULL;
9ff05123
RK		 2804 }
2805 return err;
2806}
2807
2808/**
2809 * nilfs_detach_segment_constructor - destroy the segment constructor
2810 * @sbi: nilfs_sb_info
2811 *
2812 * nilfs_detach_segment_constructor() kills the segment constructor daemon,
2813 * frees the struct nilfs_sc_info, and destroy the dirty file list.
2814 */
2815void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi)
2816{
2817 struct the_nilfs *nilfs = sbi->s_nilfs;
2818 LIST_HEAD(garbage_list);
2819
2820 down_write(&nilfs->ns_segctor_sem);
3fd3fe5a
RK		 2821 if (nilfs->ns_writer) {
2822 nilfs_segctor_destroy(nilfs->ns_writer);
2823 nilfs->ns_writer = NULL;
9ff05123
RK		 2824 }
2825
2826 /* Force to free the list of dirty files */
693dd321
RK		 2827 spin_lock(&nilfs->ns_inode_lock);
2828 if (!list_empty(&nilfs->ns_dirty_files)) {
2829 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
9ff05123
RK		 2830 nilfs_warning(sbi->s_super, __func__,
2831 "Non empty dirty list after the last "
2832 "segment construction\n");
2833 }
693dd321 2834 spin_unlock(&nilfs->ns_inode_lock);
9ff05123
RK		 2835 up_write(&nilfs->ns_segctor_sem);
2836
693dd321 2837 nilfs_dispose_list(nilfs, &garbage_list, 1);
9ff05123 2838}
Linux 6.x block layer and io_uring tree(s)