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nilfs2: move mount options to nilfs object
[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 *);
107static void nilfs_dispose_list(struct nilfs_sb_info *, struct list_head *,
108 int);
109
110#define nilfs_cnt32_gt(a, b) \
111 (typecheck(__u32, a) && typecheck(__u32, b) && \
112 ((__s32)(b) - (__s32)(a) < 0))
113#define nilfs_cnt32_ge(a, b) \
114 (typecheck(__u32, a) && typecheck(__u32, b) && \
115 ((__s32)(a) - (__s32)(b) >= 0))
116#define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
117#define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
118
9ff05123
RK		 119static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti)
120{
121 struct nilfs_transaction_info *cur_ti = current->journal_info;
122 void *save = NULL;
123
124 if (cur_ti) {
125 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
126 return ++cur_ti->ti_count;
127 else {
128 /*
129 * If journal_info field is occupied by other FS,
47420c79
RK		 130 * it is saved and will be restored on
131 * nilfs_transaction_commit().
9ff05123
RK		 132 */
133 printk(KERN_WARNING
134 "NILFS warning: journal info from a different "
135 "FS\n");
136 save = current->journal_info;
137 }
138 }
139 if (!ti) {
140 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
141 if (!ti)
142 return -ENOMEM;
143 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
144 } else {
145 ti->ti_flags = 0;
146 }
147 ti->ti_count = 0;
148 ti->ti_save = save;
149 ti->ti_magic = NILFS_TI_MAGIC;
150 current->journal_info = ti;
151 return 0;
152}
153
154/**
155 * nilfs_transaction_begin - start indivisible file operations.
156 * @sb: super block
157 * @ti: nilfs_transaction_info
158 * @vacancy_check: flags for vacancy rate checks
159 *
160 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
161 * the segment semaphore, to make a segment construction and write tasks
47420c79 162 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
9ff05123
RK		 163 * The region enclosed by these two functions can be nested. To avoid a
164 * deadlock, the semaphore is only acquired or released in the outermost call.
165 *
166 * This function allocates a nilfs_transaction_info struct to keep context
167 * information on it. It is initialized and hooked onto the current task in
168 * the outermost call. If a pre-allocated struct is given to @ti, it is used
7a65004b 169 * instead; otherwise a new struct is assigned from a slab.
9ff05123
RK		 170 *
171 * When @vacancy_check flag is set, this function will check the amount of
172 * free space, and will wait for the GC to reclaim disk space if low capacity.
173 *
174 * Return Value: On success, 0 is returned. On error, one of the following
175 * negative error code is returned.
176 *
177 * %-ENOMEM - Insufficient memory available.
178 *
9ff05123
RK		 179 * %-ENOSPC - No space left on device
180 */
181int nilfs_transaction_begin(struct super_block *sb,
182 struct nilfs_transaction_info *ti,
183 int vacancy_check)
184{
185 struct nilfs_sb_info *sbi;
186 struct the_nilfs *nilfs;
187 int ret = nilfs_prepare_segment_lock(ti);
188
189 if (unlikely(ret < 0))
190 return ret;
191 if (ret > 0)
192 return 0;
193
5beb6e0b
RK		 194 vfs_check_frozen(sb, SB_FREEZE_WRITE);
195
9ff05123
RK		 196 sbi = NILFS_SB(sb);
197 nilfs = sbi->s_nilfs;
198 down_read(&nilfs->ns_segctor_sem);
199 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
200 up_read(&nilfs->ns_segctor_sem);
201 ret = -ENOSPC;
202 goto failed;
203 }
204 return 0;
205
206 failed:
207 ti = current->journal_info;
208 current->journal_info = ti->ti_save;
209 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
210 kmem_cache_free(nilfs_transaction_cachep, ti);
211 return ret;
212}
213
214/**
47420c79 215 * nilfs_transaction_commit - commit indivisible file operations.
9ff05123 216 * @sb: super block
9ff05123 217 *
47420c79
RK		 218 * nilfs_transaction_commit() releases the read semaphore which is
219 * acquired by nilfs_transaction_begin(). This is only performed
220 * in outermost call of this function. If a commit flag is set,
221 * nilfs_transaction_commit() sets a timer to start the segment
222 * constructor. If a sync flag is set, it starts construction
223 * directly.
9ff05123 224 */
47420c79 225int nilfs_transaction_commit(struct super_block *sb)
9ff05123
RK		 226{
227 struct nilfs_transaction_info *ti = current->journal_info;
228 struct nilfs_sb_info *sbi;
229 struct nilfs_sc_info *sci;
230 int err = 0;
231
232 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
47420c79 233 ti->ti_flags |= NILFS_TI_COMMIT;
9ff05123
RK		 234 if (ti->ti_count > 0) {
235 ti->ti_count--;
236 return 0;
237 }
238 sbi = NILFS_SB(sb);
239 sci = NILFS_SC(sbi);
240 if (sci != NULL) {
241 if (ti->ti_flags & NILFS_TI_COMMIT)
242 nilfs_segctor_start_timer(sci);
243 if (atomic_read(&sbi->s_nilfs->ns_ndirtyblks) >
244 sci->sc_watermark)
245 nilfs_segctor_do_flush(sci, 0);
246 }
247 up_read(&sbi->s_nilfs->ns_segctor_sem);
248 current->journal_info = ti->ti_save;
249
250 if (ti->ti_flags & NILFS_TI_SYNC)
251 err = nilfs_construct_segment(sb);
252 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
253 kmem_cache_free(nilfs_transaction_cachep, ti);
254 return err;
255}
256
47420c79
RK		 257void nilfs_transaction_abort(struct super_block *sb)
258{
259 struct nilfs_transaction_info *ti = current->journal_info;
260
261 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
262 if (ti->ti_count > 0) {
263 ti->ti_count--;
264 return;
265 }
266 up_read(&NILFS_SB(sb)->s_nilfs->ns_segctor_sem);
267
268 current->journal_info = ti->ti_save;
269 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
270 kmem_cache_free(nilfs_transaction_cachep, ti);
271}
272
9ff05123
RK		 273void nilfs_relax_pressure_in_lock(struct super_block *sb)
274{
275 struct nilfs_sb_info *sbi = NILFS_SB(sb);
276 struct nilfs_sc_info *sci = NILFS_SC(sbi);
277 struct the_nilfs *nilfs = sbi->s_nilfs;
278
279 if (!sci || !sci->sc_flush_request)
280 return;
281
282 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
283 up_read(&nilfs->ns_segctor_sem);
284
285 down_write(&nilfs->ns_segctor_sem);
286 if (sci->sc_flush_request &&
287 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
288 struct nilfs_transaction_info *ti = current->journal_info;
289
290 ti->ti_flags |= NILFS_TI_WRITER;
291 nilfs_segctor_do_immediate_flush(sci);
292 ti->ti_flags &= ~NILFS_TI_WRITER;
293 }
294 downgrade_write(&nilfs->ns_segctor_sem);
295}
296
297static void nilfs_transaction_lock(struct nilfs_sb_info *sbi,
298 struct nilfs_transaction_info *ti,
299 int gcflag)
300{
301 struct nilfs_transaction_info *cur_ti = current->journal_info;
302
1f5abe7e 303 WARN_ON(cur_ti);
9ff05123
RK		 304 ti->ti_flags = NILFS_TI_WRITER;
305 ti->ti_count = 0;
306 ti->ti_save = cur_ti;
307 ti->ti_magic = NILFS_TI_MAGIC;
308 INIT_LIST_HEAD(&ti->ti_garbage);
309 current->journal_info = ti;
310
311 for (;;) {
312 down_write(&sbi->s_nilfs->ns_segctor_sem);
313 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &NILFS_SC(sbi)->sc_flags))
314 break;
315
316 nilfs_segctor_do_immediate_flush(NILFS_SC(sbi));
317
318 up_write(&sbi->s_nilfs->ns_segctor_sem);
319 yield();
320 }
321 if (gcflag)
322 ti->ti_flags |= NILFS_TI_GC;
323}
324
325static void nilfs_transaction_unlock(struct nilfs_sb_info *sbi)
326{
327 struct nilfs_transaction_info *ti = current->journal_info;
328
329 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
330 BUG_ON(ti->ti_count > 0);
331
332 up_write(&sbi->s_nilfs->ns_segctor_sem);
333 current->journal_info = ti->ti_save;
334 if (!list_empty(&ti->ti_garbage))
335 nilfs_dispose_list(sbi, &ti->ti_garbage, 0);
336}
337
338static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
339 struct nilfs_segsum_pointer *ssp,
340 unsigned bytes)
341{
342 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
343 unsigned blocksize = sci->sc_super->s_blocksize;
344 void *p;
345
346 if (unlikely(ssp->offset + bytes > blocksize)) {
347 ssp->offset = 0;
348 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
349 &segbuf->sb_segsum_buffers));
350 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
351 }
352 p = ssp->bh->b_data + ssp->offset;
353 ssp->offset += bytes;
354 return p;
355}
356
357/**
358 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
359 * @sci: nilfs_sc_info
360 */
361static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
362{
363 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
364 struct buffer_head *sumbh;
365 unsigned sumbytes;
366 unsigned flags = 0;
367 int err;
368
369 if (nilfs_doing_gc())
370 flags = NILFS_SS_GC;
6c43f410 371 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
9ff05123
RK		 372 if (unlikely(err))
373 return err;
374
375 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
376 sumbytes = segbuf->sb_sum.sumbytes;
377 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
378 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
379 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
380 return 0;
381}
382
383static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
384{
385 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
386 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
387 return -E2BIG; /* The current segment is filled up
388 (internal code) */
389 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
390 return nilfs_segctor_reset_segment_buffer(sci);
391}
392
393static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
394{
395 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
396 int err;
397
398 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
399 err = nilfs_segctor_feed_segment(sci);
400 if (err)
401 return err;
402 segbuf = sci->sc_curseg;
403 }
1e2b68bf 404 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
9ff05123
RK		 405 if (likely(!err))
406 segbuf->sb_sum.flags |= NILFS_SS_SR;
407 return err;
408}
409
410/*
411 * Functions for making segment summary and payloads
412 */
413static int nilfs_segctor_segsum_block_required(
414 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
415 unsigned binfo_size)
416{
417 unsigned blocksize = sci->sc_super->s_blocksize;
418 /* Size of finfo and binfo is enough small against blocksize */
419
420 return ssp->offset + binfo_size +
421 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
422 blocksize;
423}
424
425static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
426 struct inode *inode)
427{
428 sci->sc_curseg->sb_sum.nfinfo++;
429 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
430 nilfs_segctor_map_segsum_entry(
431 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
c96fa464 432
72746ac6
RK		 433 if (NILFS_I(inode)->i_root &&
434 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
c96fa464 435 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
9ff05123
RK		 436 /* skip finfo */
437}
438
439static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
440 struct inode *inode)
441{
442 struct nilfs_finfo *finfo;
443 struct nilfs_inode_info *ii;
444 struct nilfs_segment_buffer *segbuf;
6c43f410 445 __u64 cno;
9ff05123
RK		 446
447 if (sci->sc_blk_cnt == 0)
448 return;
449
450 ii = NILFS_I(inode);
6c43f410
RK		 451
452 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
453 cno = ii->i_cno;
454 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
455 cno = 0;
456 else
457 cno = sci->sc_cno;
458
9ff05123
RK		 459 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
460 sizeof(*finfo));
461 finfo->fi_ino = cpu_to_le64(inode->i_ino);
462 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
463 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
6c43f410 464 finfo->fi_cno = cpu_to_le64(cno);
9ff05123
RK		 465
466 segbuf = sci->sc_curseg;
467 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
468 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
469 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
470 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
471}
472
473static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
474 struct buffer_head *bh,
475 struct inode *inode,
476 unsigned binfo_size)
477{
478 struct nilfs_segment_buffer *segbuf;
479 int required, err = 0;
480
481 retry:
482 segbuf = sci->sc_curseg;
483 required = nilfs_segctor_segsum_block_required(
484 sci, &sci->sc_binfo_ptr, binfo_size);
485 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
486 nilfs_segctor_end_finfo(sci, inode);
487 err = nilfs_segctor_feed_segment(sci);
488 if (err)
489 return err;
490 goto retry;
491 }
492 if (unlikely(required)) {
493 err = nilfs_segbuf_extend_segsum(segbuf);
494 if (unlikely(err))
495 goto failed;
496 }
497 if (sci->sc_blk_cnt == 0)
498 nilfs_segctor_begin_finfo(sci, inode);
499
500 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
501 /* Substitution to vblocknr is delayed until update_blocknr() */
502 nilfs_segbuf_add_file_buffer(segbuf, bh);
503 sci->sc_blk_cnt++;
504 failed:
505 return err;
506}
507
9ff05123
RK		 508/*
509 * Callback functions that enumerate, mark, and collect dirty blocks
510 */
511static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
512 struct buffer_head *bh, struct inode *inode)
513{
514 int err;
515
9ff05123 516 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
e828949e
RK		 517 if (err < 0)
518 return err;
9ff05123
RK		 519
520 err = nilfs_segctor_add_file_block(sci, bh, inode,
521 sizeof(struct nilfs_binfo_v));
522 if (!err)
523 sci->sc_datablk_cnt++;
524 return err;
525}
526
527static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
528 struct buffer_head *bh,
529 struct inode *inode)
530{
e828949e 531 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
9ff05123
RK		 532}
533
534static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
535 struct buffer_head *bh,
536 struct inode *inode)
537{
1f5abe7e 538 WARN_ON(!buffer_dirty(bh));
9ff05123
RK		 539 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
540}
541
542static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
543 struct nilfs_segsum_pointer *ssp,
544 union nilfs_binfo *binfo)
545{
546 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
547 sci, ssp, sizeof(*binfo_v));
548 *binfo_v = binfo->bi_v;
549}
550
551static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
552 struct nilfs_segsum_pointer *ssp,
553 union nilfs_binfo *binfo)
554{
555 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
556 sci, ssp, sizeof(*vblocknr));
557 *vblocknr = binfo->bi_v.bi_vblocknr;
558}
559
4e819509 560static struct nilfs_sc_operations nilfs_sc_file_ops = {
9ff05123
RK		 561 .collect_data = nilfs_collect_file_data,
562 .collect_node = nilfs_collect_file_node,
563 .collect_bmap = nilfs_collect_file_bmap,
564 .write_data_binfo = nilfs_write_file_data_binfo,
565 .write_node_binfo = nilfs_write_file_node_binfo,
566};
567
568static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
569 struct buffer_head *bh, struct inode *inode)
570{
571 int err;
572
573 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
e828949e
RK		 574 if (err < 0)
575 return err;
9ff05123
RK		 576
577 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
578 if (!err)
579 sci->sc_datablk_cnt++;
580 return err;
581}
582
583static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
584 struct buffer_head *bh, struct inode *inode)
585{
1f5abe7e 586 WARN_ON(!buffer_dirty(bh));
9ff05123
RK		 587 return nilfs_segctor_add_file_block(sci, bh, inode,
588 sizeof(struct nilfs_binfo_dat));
589}
590
591static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
592 struct nilfs_segsum_pointer *ssp,
593 union nilfs_binfo *binfo)
594{
595 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
596 sizeof(*blkoff));
597 *blkoff = binfo->bi_dat.bi_blkoff;
598}
599
600static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
601 struct nilfs_segsum_pointer *ssp,
602 union nilfs_binfo *binfo)
603{
604 struct nilfs_binfo_dat *binfo_dat =
605 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
606 *binfo_dat = binfo->bi_dat;
607}
608
4e819509 609static struct nilfs_sc_operations nilfs_sc_dat_ops = {
9ff05123
RK		 610 .collect_data = nilfs_collect_dat_data,
611 .collect_node = nilfs_collect_file_node,
612 .collect_bmap = nilfs_collect_dat_bmap,
613 .write_data_binfo = nilfs_write_dat_data_binfo,
614 .write_node_binfo = nilfs_write_dat_node_binfo,
615};
616
4e819509 617static struct nilfs_sc_operations nilfs_sc_dsync_ops = {
9ff05123
RK		 618 .collect_data = nilfs_collect_file_data,
619 .collect_node = NULL,
620 .collect_bmap = NULL,
621 .write_data_binfo = nilfs_write_file_data_binfo,
622 .write_node_binfo = NULL,
623};
624
f30bf3e4
RK		 625static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
626 struct list_head *listp,
627 size_t nlimit,
628 loff_t start, loff_t end)
9ff05123 629{
9ff05123
RK		 630 struct address_space *mapping = inode->i_mapping;
631 struct pagevec pvec;
f30bf3e4
RK		 632 pgoff_t index = 0, last = ULONG_MAX;
633 size_t ndirties = 0;
634 int i;
9ff05123 635
f30bf3e4
RK		 636 if (unlikely(start != 0 || end != LLONG_MAX)) {
637 /*
638 * A valid range is given for sync-ing data pages. The
639 * range is rounded to per-page; extra dirty buffers
640 * may be included if blocksize < pagesize.
641 */
642 index = start >> PAGE_SHIFT;
643 last = end >> PAGE_SHIFT;
644 }
9ff05123
RK		 645 pagevec_init(&pvec, 0);
646 repeat:
f30bf3e4
RK		 647 if (unlikely(index > last) ||
648 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
649 min_t(pgoff_t, last - index,
650 PAGEVEC_SIZE - 1) + 1))
651 return ndirties;
9ff05123
RK		 652
653 for (i = 0; i < pagevec_count(&pvec); i++) {
654 struct buffer_head *bh, *head;
655 struct page *page = pvec.pages[i];
656
f30bf3e4
RK		 657 if (unlikely(page->index > last))
658 break;
659
9ff05123
RK		 660 if (mapping->host) {
661 lock_page(page);
662 if (!page_has_buffers(page))
663 create_empty_buffers(page,
664 1 << inode->i_blkbits, 0);
665 unlock_page(page);
666 }
667
668 bh = head = page_buffers(page);
669 do {
f30bf3e4
RK		 670 if (!buffer_dirty(bh))
671 continue;
672 get_bh(bh);
673 list_add_tail(&bh->b_assoc_buffers, listp);
674 ndirties++;
675 if (unlikely(ndirties >= nlimit)) {
676 pagevec_release(&pvec);
677 cond_resched();
678 return ndirties;
9ff05123 679 }
f30bf3e4 680 } while (bh = bh->b_this_page, bh != head);
9ff05123
RK		 681 }
682 pagevec_release(&pvec);
683 cond_resched();
f30bf3e4 684 goto repeat;
9ff05123
RK		 685}
686
687static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
688 struct list_head *listp)
689{
690 struct nilfs_inode_info *ii = NILFS_I(inode);
691 struct address_space *mapping = &ii->i_btnode_cache;
692 struct pagevec pvec;
693 struct buffer_head *bh, *head;
694 unsigned int i;
695 pgoff_t index = 0;
696
697 pagevec_init(&pvec, 0);
698
699 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
700 PAGEVEC_SIZE)) {
701 for (i = 0; i < pagevec_count(&pvec); i++) {
702 bh = head = page_buffers(pvec.pages[i]);
703 do {
704 if (buffer_dirty(bh)) {
705 get_bh(bh);
706 list_add_tail(&bh->b_assoc_buffers,
707 listp);
708 }
709 bh = bh->b_this_page;
710 } while (bh != head);
711 }
712 pagevec_release(&pvec);
713 cond_resched();
714 }
715}
716
717static void nilfs_dispose_list(struct nilfs_sb_info *sbi,
718 struct list_head *head, int force)
719{
720 struct nilfs_inode_info *ii, *n;
721 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
722 unsigned nv = 0;
723
724 while (!list_empty(head)) {
725 spin_lock(&sbi->s_inode_lock);
726 list_for_each_entry_safe(ii, n, head, i_dirty) {
727 list_del_init(&ii->i_dirty);
728 if (force) {
729 if (unlikely(ii->i_bh)) {
730 brelse(ii->i_bh);
731 ii->i_bh = NULL;
732 }
733 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
734 set_bit(NILFS_I_QUEUED, &ii->i_state);
735 list_add_tail(&ii->i_dirty,
736 &sbi->s_dirty_files);
737 continue;
738 }
739 ivec[nv++] = ii;
740 if (nv == SC_N_INODEVEC)
741 break;
742 }
743 spin_unlock(&sbi->s_inode_lock);
744
745 for (pii = ivec; nv > 0; pii++, nv--)
746 iput(&(*pii)->vfs_inode);
747 }
748}
749
e912a5b6
RK		 750static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
751 struct nilfs_root *root)
9ff05123 752{
9ff05123
RK		 753 int ret = 0;
754
e912a5b6 755 if (nilfs_mdt_fetch_dirty(root->ifile))
9ff05123
RK		 756 ret++;
757 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
758 ret++;
759 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
760 ret++;
365e215c
RK		 761 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
762 ret++;
9ff05123
RK		 763 return ret;
764}
765
766static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
767{
768 return list_empty(&sci->sc_dirty_files) &&
769 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
071cb4b8 770 sci->sc_nfreesegs == 0 &&
9ff05123
RK		 771 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
772}
773
774static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
775{
776 struct nilfs_sb_info *sbi = sci->sc_sbi;
777 int ret = 0;
778
e912a5b6 779 if (nilfs_test_metadata_dirty(sbi->s_nilfs, sci->sc_root))
9ff05123
RK		 780 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
781
782 spin_lock(&sbi->s_inode_lock);
783 if (list_empty(&sbi->s_dirty_files) && nilfs_segctor_clean(sci))
784 ret++;
785
786 spin_unlock(&sbi->s_inode_lock);
787 return ret;
788}
789
790static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
791{
792 struct nilfs_sb_info *sbi = sci->sc_sbi;
793 struct the_nilfs *nilfs = sbi->s_nilfs;
794
e912a5b6 795 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
9ff05123
RK		 796 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
797 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
365e215c 798 nilfs_mdt_clear_dirty(nilfs->ns_dat);
9ff05123
RK		 799}
800
801static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
802{
803 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
804 struct buffer_head *bh_cp;
805 struct nilfs_checkpoint *raw_cp;
806 int err;
807
808 /* XXX: this interface will be changed */
809 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
810 &raw_cp, &bh_cp);
811 if (likely(!err)) {
812 /* The following code is duplicated with cpfile. But, it is
813 needed to collect the checkpoint even if it was not newly
814 created */
815 nilfs_mdt_mark_buffer_dirty(bh_cp);
816 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
817 nilfs_cpfile_put_checkpoint(
818 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
1f5abe7e
RK		 819 } else
820 WARN_ON(err == -EINVAL || err == -ENOENT);
821
9ff05123
RK		 822 return err;
823}
824
825static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
826{
827 struct nilfs_sb_info *sbi = sci->sc_sbi;
828 struct the_nilfs *nilfs = sbi->s_nilfs;
829 struct buffer_head *bh_cp;
830 struct nilfs_checkpoint *raw_cp;
831 int err;
832
833 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
834 &raw_cp, &bh_cp);
835 if (unlikely(err)) {
1f5abe7e 836 WARN_ON(err == -EINVAL || err == -ENOENT);
9ff05123
RK		 837 goto failed_ibh;
838 }
839 raw_cp->cp_snapshot_list.ssl_next = 0;
840 raw_cp->cp_snapshot_list.ssl_prev = 0;
841 raw_cp->cp_inodes_count =
b7c06342 842 cpu_to_le64(atomic_read(&sci->sc_root->inodes_count));
9ff05123 843 raw_cp->cp_blocks_count =
b7c06342 844 cpu_to_le64(atomic_read(&sci->sc_root->blocks_count));
9ff05123
RK		 845 raw_cp->cp_nblk_inc =
846 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
847 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
848 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
458c5b08 849
c96fa464
RK		 850 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
851 nilfs_checkpoint_clear_minor(raw_cp);
852 else
853 nilfs_checkpoint_set_minor(raw_cp);
854
e912a5b6
RK		 855 nilfs_write_inode_common(sci->sc_root->ifile,
856 &raw_cp->cp_ifile_inode, 1);
9ff05123
RK		 857 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
858 return 0;
859
860 failed_ibh:
861 return err;
862}
863
864static void nilfs_fill_in_file_bmap(struct inode *ifile,
865 struct nilfs_inode_info *ii)
866
867{
868 struct buffer_head *ibh;
869 struct nilfs_inode *raw_inode;
870
871 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
872 ibh = ii->i_bh;
873 BUG_ON(!ibh);
874 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
875 ibh);
876 nilfs_bmap_write(ii->i_bmap, raw_inode);
877 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
878 }
879}
880
e912a5b6 881static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
9ff05123
RK		 882{
883 struct nilfs_inode_info *ii;
884
885 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
e912a5b6 886 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
9ff05123
RK		 887 set_bit(NILFS_I_COLLECTED, &ii->i_state);
888 }
9ff05123
RK		 889}
890
9ff05123
RK		 891static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
892 struct the_nilfs *nilfs)
893{
1e2b68bf
RK		 894 struct buffer_head *bh_sr;
895 struct nilfs_super_root *raw_sr;
9ff05123
RK		 896 unsigned isz = nilfs->ns_inode_size;
897
1e2b68bf
RK		 898 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
899 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
900
9ff05123
RK		 901 raw_sr->sr_bytes = cpu_to_le16(NILFS_SR_BYTES);
902 raw_sr->sr_nongc_ctime
903 = cpu_to_le64(nilfs_doing_gc() ?
904 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
905 raw_sr->sr_flags = 0;
906
365e215c 907 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
3961f0e2
RK		 908 NILFS_SR_DAT_OFFSET(isz), 1);
909 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
910 NILFS_SR_CPFILE_OFFSET(isz), 1);
911 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
912 NILFS_SR_SUFILE_OFFSET(isz), 1);
9ff05123
RK		 913}
914
915static void nilfs_redirty_inodes(struct list_head *head)
916{
917 struct nilfs_inode_info *ii;
918
919 list_for_each_entry(ii, head, i_dirty) {
920 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
921 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
922 }
923}
924
925static void nilfs_drop_collected_inodes(struct list_head *head)
926{
927 struct nilfs_inode_info *ii;
928
929 list_for_each_entry(ii, head, i_dirty) {
930 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
931 continue;
932
933 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
934 set_bit(NILFS_I_UPDATED, &ii->i_state);
935 }
936}
937
9ff05123
RK		 938static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
939 struct inode *inode,
940 struct list_head *listp,
941 int (*collect)(struct nilfs_sc_info *,
942 struct buffer_head *,
943 struct inode *))
944{
945 struct buffer_head *bh, *n;
946 int err = 0;
947
948 if (collect) {
949 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
950 list_del_init(&bh->b_assoc_buffers);
951 err = collect(sci, bh, inode);
952 brelse(bh);
953 if (unlikely(err))
954 goto dispose_buffers;
955 }
956 return 0;
957 }
958
959 dispose_buffers:
960 while (!list_empty(listp)) {
961 bh = list_entry(listp->next, struct buffer_head,
962 b_assoc_buffers);
963 list_del_init(&bh->b_assoc_buffers);
964 brelse(bh);
965 }
966 return err;
967}
968
f30bf3e4
RK		 969static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
970{
971 /* Remaining number of blocks within segment buffer */
972 return sci->sc_segbuf_nblocks -
973 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
974}
975
9ff05123
RK		 976static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
977 struct inode *inode,
978 struct nilfs_sc_operations *sc_ops)
979{
980 LIST_HEAD(data_buffers);
981 LIST_HEAD(node_buffers);
f30bf3e4 982 int err;
9ff05123
RK		 983
984 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
f30bf3e4
RK		 985 size_t n, rest = nilfs_segctor_buffer_rest(sci);
986
987 n = nilfs_lookup_dirty_data_buffers(
988 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
989 if (n > rest) {
990 err = nilfs_segctor_apply_buffers(
9ff05123 991 sci, inode, &data_buffers,
f30bf3e4
RK		 992 sc_ops->collect_data);
993 BUG_ON(!err); /* always receive -E2BIG or true error */
9ff05123
RK		 994 goto break_or_fail;
995 }
996 }
997 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
998
999 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1000 err = nilfs_segctor_apply_buffers(
1001 sci, inode, &data_buffers, sc_ops->collect_data);
1002 if (unlikely(err)) {
1003 /* dispose node list */
1004 nilfs_segctor_apply_buffers(
1005 sci, inode, &node_buffers, NULL);
1006 goto break_or_fail;
1007 }
1008 sci->sc_stage.flags |= NILFS_CF_NODE;
1009 }
1010 /* Collect node */
1011 err = nilfs_segctor_apply_buffers(
1012 sci, inode, &node_buffers, sc_ops->collect_node);
1013 if (unlikely(err))
1014 goto break_or_fail;
1015
1016 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1017 err = nilfs_segctor_apply_buffers(
1018 sci, inode, &node_buffers, sc_ops->collect_bmap);
1019 if (unlikely(err))
1020 goto break_or_fail;
1021
1022 nilfs_segctor_end_finfo(sci, inode);
1023 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1024
1025 break_or_fail:
1026 return err;
1027}
1028
1029static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1030 struct inode *inode)
1031{
1032 LIST_HEAD(data_buffers);
f30bf3e4
RK		 1033 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1034 int err;
9ff05123 1035
f30bf3e4
RK		 1036 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1037 sci->sc_dsync_start,
1038 sci->sc_dsync_end);
1039
1040 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1041 nilfs_collect_file_data);
1042 if (!err) {
9ff05123 1043 nilfs_segctor_end_finfo(sci, inode);
f30bf3e4
RK		 1044 BUG_ON(n > rest);
1045 /* always receive -E2BIG or true error if n > rest */
1046 }
9ff05123
RK		 1047 return err;
1048}
1049
1050static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1051{
1052 struct nilfs_sb_info *sbi = sci->sc_sbi;
1053 struct the_nilfs *nilfs = sbi->s_nilfs;
1054 struct list_head *head;
1055 struct nilfs_inode_info *ii;
071cb4b8 1056 size_t ndone;
9ff05123
RK		 1057 int err = 0;
1058
1059 switch (sci->sc_stage.scnt) {
1060 case NILFS_ST_INIT:
1061 /* Pre-processes */
1062 sci->sc_stage.flags = 0;
1063
1064 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1065 sci->sc_nblk_inc = 0;
1066 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1067 if (mode == SC_LSEG_DSYNC) {
1068 sci->sc_stage.scnt = NILFS_ST_DSYNC;
1069 goto dsync_mode;
1070 }
1071 }
1072
1073 sci->sc_stage.dirty_file_ptr = NULL;
1074 sci->sc_stage.gc_inode_ptr = NULL;
1075 if (mode == SC_FLUSH_DAT) {
1076 sci->sc_stage.scnt = NILFS_ST_DAT;
1077 goto dat_stage;
1078 }
1079 sci->sc_stage.scnt++; /* Fall through */
1080 case NILFS_ST_GC:
1081 if (nilfs_doing_gc()) {
1082 head = &sci->sc_gc_inodes;
1083 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1084 head, i_dirty);
1085 list_for_each_entry_continue(ii, head, i_dirty) {
1086 err = nilfs_segctor_scan_file(
1087 sci, &ii->vfs_inode,
1088 &nilfs_sc_file_ops);
1089 if (unlikely(err)) {
1090 sci->sc_stage.gc_inode_ptr = list_entry(
1091 ii->i_dirty.prev,
1092 struct nilfs_inode_info,
1093 i_dirty);
1094 goto break_or_fail;
1095 }
1096 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1097 }
1098 sci->sc_stage.gc_inode_ptr = NULL;
1099 }
1100 sci->sc_stage.scnt++; /* Fall through */
1101 case NILFS_ST_FILE:
1102 head = &sci->sc_dirty_files;
1103 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1104 i_dirty);
1105 list_for_each_entry_continue(ii, head, i_dirty) {
1106 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1107
1108 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1109 &nilfs_sc_file_ops);
1110 if (unlikely(err)) {
1111 sci->sc_stage.dirty_file_ptr =
1112 list_entry(ii->i_dirty.prev,
1113 struct nilfs_inode_info,
1114 i_dirty);
1115 goto break_or_fail;
1116 }
1117 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1118 /* XXX: required ? */
1119 }
1120 sci->sc_stage.dirty_file_ptr = NULL;
1121 if (mode == SC_FLUSH_FILE) {
1122 sci->sc_stage.scnt = NILFS_ST_DONE;
1123 return 0;
1124 }
9ff05123
RK		 1125 sci->sc_stage.scnt++;
1126 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1127 /* Fall through */
1128 case NILFS_ST_IFILE:
e912a5b6 1129 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
9ff05123
RK		 1130 &nilfs_sc_file_ops);
1131 if (unlikely(err))
1132 break;
1133 sci->sc_stage.scnt++;
1134 /* Creating a checkpoint */
1135 err = nilfs_segctor_create_checkpoint(sci);
1136 if (unlikely(err))
1137 break;
1138 /* Fall through */
1139 case NILFS_ST_CPFILE:
1140 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1141 &nilfs_sc_file_ops);
1142 if (unlikely(err))
1143 break;
1144 sci->sc_stage.scnt++; /* Fall through */
1145 case NILFS_ST_SUFILE:
071cb4b8
RK		 1146 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1147 sci->sc_nfreesegs, &ndone);
1148 if (unlikely(err)) {
1149 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1150 sci->sc_freesegs, ndone,
1151 NULL);
9ff05123 1152 break;
071cb4b8
RK		 1153 }
1154 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1155
9ff05123
RK		 1156 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1157 &nilfs_sc_file_ops);
1158 if (unlikely(err))
1159 break;
1160 sci->sc_stage.scnt++; /* Fall through */
1161 case NILFS_ST_DAT:
1162 dat_stage:
365e215c 1163 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
9ff05123
RK		 1164 &nilfs_sc_dat_ops);
1165 if (unlikely(err))
1166 break;
1167 if (mode == SC_FLUSH_DAT) {
1168 sci->sc_stage.scnt = NILFS_ST_DONE;
1169 return 0;
1170 }
1171 sci->sc_stage.scnt++; /* Fall through */
1172 case NILFS_ST_SR:
1173 if (mode == SC_LSEG_SR) {
1174 /* Appending a super root */
1175 err = nilfs_segctor_add_super_root(sci);
1176 if (unlikely(err))
1177 break;
1178 }
1179 /* End of a logical segment */
1180 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1181 sci->sc_stage.scnt = NILFS_ST_DONE;
1182 return 0;
1183 case NILFS_ST_DSYNC:
1184 dsync_mode:
1185 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
f30bf3e4 1186 ii = sci->sc_dsync_inode;
9ff05123
RK		 1187 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1188 break;
1189
1190 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1191 if (unlikely(err))
1192 break;
9ff05123
RK		 1193 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1194 sci->sc_stage.scnt = NILFS_ST_DONE;
1195 return 0;
1196 case NILFS_ST_DONE:
1197 return 0;
1198 default:
1199 BUG();
1200 }
1201
1202 break_or_fail:
1203 return err;
1204}
1205
a694291a
RK		 1206/**
1207 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1208 * @sci: nilfs_sc_info
1209 * @nilfs: nilfs object
1210 */
9ff05123
RK		 1211static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1212 struct the_nilfs *nilfs)
1213{
a694291a 1214 struct nilfs_segment_buffer *segbuf, *prev;
9ff05123 1215 __u64 nextnum;
a694291a 1216 int err, alloc = 0;
9ff05123 1217
a694291a
RK		 1218 segbuf = nilfs_segbuf_new(sci->sc_super);
1219 if (unlikely(!segbuf))
1220 return -ENOMEM;
9ff05123 1221
a694291a
RK		 1222 if (list_empty(&sci->sc_write_logs)) {
1223 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1224 nilfs->ns_pseg_offset, nilfs);
1225 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1226 nilfs_shift_to_next_segment(nilfs);
1227 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1228 }
9ff05123 1229
a694291a
RK		 1230 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1231 nextnum = nilfs->ns_nextnum;
1232
1233 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1234 /* Start from the head of a new full segment */
1235 alloc++;
1236 } else {
1237 /* Continue logs */
1238 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1239 nilfs_segbuf_map_cont(segbuf, prev);
1240 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1241 nextnum = prev->sb_nextnum;
1242
1243 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1244 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1245 segbuf->sb_sum.seg_seq++;
1246 alloc++;
1247 }
9ff05123 1248 }
9ff05123 1249
61a189e9 1250 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
a694291a
RK		 1251 if (err)
1252 goto failed;
9ff05123 1253
a694291a 1254 if (alloc) {
cece5520 1255 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
a694291a
RK		 1256 if (err)
1257 goto failed;
1258 }
9ff05123
RK		 1259 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1260
a694291a
RK		 1261 BUG_ON(!list_empty(&sci->sc_segbufs));
1262 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1263 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
cece5520 1264 return 0;
a694291a
RK		 1265
1266 failed:
1267 nilfs_segbuf_free(segbuf);
1268 return err;
9ff05123
RK		 1269}
1270
1271static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1272 struct the_nilfs *nilfs, int nadd)
1273{
e29df395 1274 struct nilfs_segment_buffer *segbuf, *prev;
9ff05123
RK		 1275 struct inode *sufile = nilfs->ns_sufile;
1276 __u64 nextnextnum;
1277 LIST_HEAD(list);
1278 int err, ret, i;
1279
1280 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1281 /*
1282 * Since the segment specified with nextnum might be allocated during
1283 * the previous construction, the buffer including its segusage may
1284 * not be dirty. The following call ensures that the buffer is dirty
1285 * and will pin the buffer on memory until the sufile is written.
1286 */
61a189e9 1287 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
9ff05123
RK		 1288 if (unlikely(err))
1289 return err;
1290
1291 for (i = 0; i < nadd; i++) {
1292 /* extend segment info */
1293 err = -ENOMEM;
1294 segbuf = nilfs_segbuf_new(sci->sc_super);
1295 if (unlikely(!segbuf))
1296 goto failed;
1297
1298 /* map this buffer to region of segment on-disk */
cece5520 1299 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
9ff05123
RK		 1300 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1301
1302 /* allocate the next next full segment */
1303 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1304 if (unlikely(err))
1305 goto failed_segbuf;
1306
1307 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1308 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1309
1310 list_add_tail(&segbuf->sb_list, &list);
1311 prev = segbuf;
1312 }
0935db74 1313 list_splice_tail(&list, &sci->sc_segbufs);
9ff05123
RK		 1314 return 0;
1315
1316 failed_segbuf:
1317 nilfs_segbuf_free(segbuf);
1318 failed:
e29df395 1319 list_for_each_entry(segbuf, &list, sb_list) {
9ff05123 1320 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1321 WARN_ON(ret); /* never fails */
9ff05123 1322 }
e29df395 1323 nilfs_destroy_logs(&list);
9ff05123
RK		 1324 return err;
1325}
1326
a694291a
RK		 1327static void nilfs_free_incomplete_logs(struct list_head *logs,
1328 struct the_nilfs *nilfs)
9ff05123 1329{
a694291a
RK		 1330 struct nilfs_segment_buffer *segbuf, *prev;
1331 struct inode *sufile = nilfs->ns_sufile;
9284ad2a 1332 int ret;
9ff05123 1333
a694291a 1334 segbuf = NILFS_FIRST_SEGBUF(logs);
9ff05123 1335 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
a694291a 1336 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1337 WARN_ON(ret); /* never fails */
9ff05123 1338 }
9284ad2a 1339 if (atomic_read(&segbuf->sb_err)) {
9ff05123
RK		 1340 /* Case 1: The first segment failed */
1341 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1342 /* Case 1a: Partial segment appended into an existing
1343 segment */
1344 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1345 segbuf->sb_fseg_end);
1346 else /* Case 1b: New full segment */
1347 set_nilfs_discontinued(nilfs);
9ff05123
RK		 1348 }
1349
a694291a
RK		 1350 prev = segbuf;
1351 list_for_each_entry_continue(segbuf, logs, sb_list) {
1352 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1353 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1354 WARN_ON(ret); /* never fails */
1355 }
9284ad2a
RK		 1356 if (atomic_read(&segbuf->sb_err) &&
1357 segbuf->sb_segnum != nilfs->ns_nextnum)
1358 /* Case 2: extended segment (!= next) failed */
a694291a
RK		 1359 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1360 prev = segbuf;
9ff05123 1361 }
9ff05123
RK		 1362}
1363
1364static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1365 struct inode *sufile)
1366{
1367 struct nilfs_segment_buffer *segbuf;
9ff05123
RK		 1368 unsigned long live_blocks;
1369 int ret;
1370
1371 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
9ff05123
RK		 1372 live_blocks = segbuf->sb_sum.nblocks +
1373 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
071ec54d
RK		 1374 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1375 live_blocks,
1376 sci->sc_seg_ctime);
1377 WARN_ON(ret); /* always succeed because the segusage is dirty */
9ff05123
RK		 1378 }
1379}
1380
a694291a 1381static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
9ff05123
RK		 1382{
1383 struct nilfs_segment_buffer *segbuf;
9ff05123
RK		 1384 int ret;
1385
a694291a 1386 segbuf = NILFS_FIRST_SEGBUF(logs);
071ec54d
RK		 1387 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1388 segbuf->sb_pseg_start -
1389 segbuf->sb_fseg_start, 0);
1390 WARN_ON(ret); /* always succeed because the segusage is dirty */
9ff05123 1391
a694291a 1392 list_for_each_entry_continue(segbuf, logs, sb_list) {
071ec54d
RK		 1393 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1394 0, 0);
1f5abe7e 1395 WARN_ON(ret); /* always succeed */
9ff05123
RK		 1396 }
1397}
1398
1399static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1400 struct nilfs_segment_buffer *last,
1401 struct inode *sufile)
1402{
e29df395 1403 struct nilfs_segment_buffer *segbuf = last;
9ff05123
RK		 1404 int ret;
1405
e29df395 1406 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
9ff05123
RK		 1407 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1408 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1f5abe7e 1409 WARN_ON(ret);
9ff05123 1410 }
e29df395 1411 nilfs_truncate_logs(&sci->sc_segbufs, last);
9ff05123
RK		 1412}
1413
1414
1415static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1416 struct the_nilfs *nilfs, int mode)
1417{
1418 struct nilfs_cstage prev_stage = sci->sc_stage;
1419 int err, nadd = 1;
1420
1421 /* Collection retry loop */
1422 for (;;) {
9ff05123
RK		 1423 sci->sc_nblk_this_inc = 0;
1424 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1425
1426 err = nilfs_segctor_reset_segment_buffer(sci);
1427 if (unlikely(err))
1428 goto failed;
1429
1430 err = nilfs_segctor_collect_blocks(sci, mode);
1431 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1432 if (!err)
1433 break;
1434
1435 if (unlikely(err != -E2BIG))
1436 goto failed;
1437
1438 /* The current segment is filled up */
1439 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE)
1440 break;
1441
2d8428ac
RK		 1442 nilfs_clear_logs(&sci->sc_segbufs);
1443
1444 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1445 if (unlikely(err))
1446 return err;
1447
071cb4b8
RK		 1448 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1449 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1450 sci->sc_freesegs,
1451 sci->sc_nfreesegs,
1452 NULL);
1453 WARN_ON(err); /* do not happen */
1454 }
9ff05123
RK		 1455 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1456 sci->sc_stage = prev_stage;
1457 }
1458 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1459 return 0;
1460
1461 failed:
1462 return err;
1463}
1464
1465static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1466 struct buffer_head *new_bh)
1467{
1468 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1469
1470 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1471 /* The caller must release old_bh */
1472}
1473
1474static int
1475nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1476 struct nilfs_segment_buffer *segbuf,
1477 int mode)
1478{
1479 struct inode *inode = NULL;
1480 sector_t blocknr;
1481 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1482 unsigned long nblocks = 0, ndatablk = 0;
1483 struct nilfs_sc_operations *sc_op = NULL;
1484 struct nilfs_segsum_pointer ssp;
1485 struct nilfs_finfo *finfo = NULL;
1486 union nilfs_binfo binfo;
1487 struct buffer_head *bh, *bh_org;
1488 ino_t ino = 0;
1489 int err = 0;
1490
1491 if (!nfinfo)
1492 goto out;
1493
1494 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1495 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1496 ssp.offset = sizeof(struct nilfs_segment_summary);
1497
1498 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1e2b68bf 1499 if (bh == segbuf->sb_super_root)
9ff05123
RK		 1500 break;
1501 if (!finfo) {
1502 finfo = nilfs_segctor_map_segsum_entry(
1503 sci, &ssp, sizeof(*finfo));
1504 ino = le64_to_cpu(finfo->fi_ino);
1505 nblocks = le32_to_cpu(finfo->fi_nblocks);
1506 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1507
1508 if (buffer_nilfs_node(bh))
1509 inode = NILFS_BTNC_I(bh->b_page->mapping);
1510 else
1511 inode = NILFS_AS_I(bh->b_page->mapping);
1512
1513 if (mode == SC_LSEG_DSYNC)
1514 sc_op = &nilfs_sc_dsync_ops;
1515 else if (ino == NILFS_DAT_INO)
1516 sc_op = &nilfs_sc_dat_ops;
1517 else /* file blocks */
1518 sc_op = &nilfs_sc_file_ops;
1519 }
1520 bh_org = bh;
1521 get_bh(bh_org);
1522 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1523 &binfo);
1524 if (bh != bh_org)
1525 nilfs_list_replace_buffer(bh_org, bh);
1526 brelse(bh_org);
1527 if (unlikely(err))
1528 goto failed_bmap;
1529
1530 if (ndatablk > 0)
1531 sc_op->write_data_binfo(sci, &ssp, &binfo);
1532 else
1533 sc_op->write_node_binfo(sci, &ssp, &binfo);
1534
1535 blocknr++;
1536 if (--nblocks == 0) {
1537 finfo = NULL;
1538 if (--nfinfo == 0)
1539 break;
1540 } else if (ndatablk > 0)
1541 ndatablk--;
1542 }
1543 out:
1544 return 0;
1545
1546 failed_bmap:
9ff05123
RK		 1547 return err;
1548}
1549
1550static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1551{
1552 struct nilfs_segment_buffer *segbuf;
1553 int err;
1554
1555 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1556 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1557 if (unlikely(err))
1558 return err;
1559 nilfs_segbuf_fill_in_segsum(segbuf);
1560 }
1561 return 0;
1562}
1563
1564static int
1565nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out)
1566{
1567 struct page *clone_page;
1568 struct buffer_head *bh, *head, *bh2;
1569 void *kaddr;
1570
1571 bh = head = page_buffers(page);
1572
1573 clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0);
1574 if (unlikely(!clone_page))
1575 return -ENOMEM;
1576
1577 bh2 = page_buffers(clone_page);
1578 kaddr = kmap_atomic(page, KM_USER0);
1579 do {
1580 if (list_empty(&bh->b_assoc_buffers))
1581 continue;
1582 get_bh(bh2);
1583 page_cache_get(clone_page); /* for each bh */
1584 memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size);
1585 bh2->b_blocknr = bh->b_blocknr;
1586 list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers);
1587 list_add_tail(&bh->b_assoc_buffers, out);
1588 } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head);
1589 kunmap_atomic(kaddr, KM_USER0);
1590
1591 if (!TestSetPageWriteback(clone_page))
f629d1c9 1592 account_page_writeback(clone_page);
9ff05123
RK		 1593 unlock_page(clone_page);
1594
1595 return 0;
1596}
1597
1598static int nilfs_test_page_to_be_frozen(struct page *page)
1599{
1600 struct address_space *mapping = page->mapping;
1601
1602 if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode))
1603 return 0;
1604
1605 if (page_mapped(page)) {
1606 ClearPageChecked(page);
1607 return 1;
1608 }
1609 return PageChecked(page);
1610}
1611
1612static int nilfs_begin_page_io(struct page *page, struct list_head *out)
1613{
1614 if (!page || PageWriteback(page))
1615 /* For split b-tree node pages, this function may be called
1616 twice. We ignore the 2nd or later calls by this check. */
1617 return 0;
1618
1619 lock_page(page);
1620 clear_page_dirty_for_io(page);
1621 set_page_writeback(page);
1622 unlock_page(page);
1623
1624 if (nilfs_test_page_to_be_frozen(page)) {
1625 int err = nilfs_copy_replace_page_buffers(page, out);
1626 if (unlikely(err))
1627 return err;
1628 }
1629 return 0;
1630}
1631
1632static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci,
1633 struct page **failed_page)
1634{
1635 struct nilfs_segment_buffer *segbuf;
1636 struct page *bd_page = NULL, *fs_page = NULL;
1637 struct list_head *list = &sci->sc_copied_buffers;
1638 int err;
1639
1640 *failed_page = NULL;
1641 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1642 struct buffer_head *bh;
1643
1644 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1645 b_assoc_buffers) {
1646 if (bh->b_page != bd_page) {
1647 if (bd_page) {
1648 lock_page(bd_page);
1649 clear_page_dirty_for_io(bd_page);
1650 set_page_writeback(bd_page);
1651 unlock_page(bd_page);
1652 }
1653 bd_page = bh->b_page;
1654 }
1655 }
1656
1657 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1658 b_assoc_buffers) {
1e2b68bf 1659 if (bh == segbuf->sb_super_root) {
9ff05123
RK		 1660 if (bh->b_page != bd_page) {
1661 lock_page(bd_page);
1662 clear_page_dirty_for_io(bd_page);
1663 set_page_writeback(bd_page);
1664 unlock_page(bd_page);
1665 bd_page = bh->b_page;
1666 }
1667 break;
1668 }
1669 if (bh->b_page != fs_page) {
1670 err = nilfs_begin_page_io(fs_page, list);
1671 if (unlikely(err)) {
1672 *failed_page = fs_page;
1673 goto out;
1674 }
1675 fs_page = bh->b_page;
1676 }
1677 }
1678 }
1679 if (bd_page) {
1680 lock_page(bd_page);
1681 clear_page_dirty_for_io(bd_page);
1682 set_page_writeback(bd_page);
1683 unlock_page(bd_page);
1684 }
1685 err = nilfs_begin_page_io(fs_page, list);
1686 if (unlikely(err))
1687 *failed_page = fs_page;
1688 out:
1689 return err;
1690}
1691
1692static int nilfs_segctor_write(struct nilfs_sc_info *sci,
9c965bac 1693 struct the_nilfs *nilfs)
9ff05123 1694{
d1c6b72a 1695 int ret;
9ff05123 1696
d1c6b72a 1697 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
a694291a
RK		 1698 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1699 return ret;
9ff05123
RK		 1700}
1701
9ff05123
RK		 1702static void __nilfs_end_page_io(struct page *page, int err)
1703{
9ff05123
RK		 1704 if (!err) {
1705 if (!nilfs_page_buffers_clean(page))
1706 __set_page_dirty_nobuffers(page);
1707 ClearPageError(page);
1708 } else {
1709 __set_page_dirty_nobuffers(page);
1710 SetPageError(page);
1711 }
1712
1713 if (buffer_nilfs_allocated(page_buffers(page))) {
1714 if (TestClearPageWriteback(page))
1715 dec_zone_page_state(page, NR_WRITEBACK);
1716 } else
1717 end_page_writeback(page);
1718}
1719
1720static void nilfs_end_page_io(struct page *page, int err)
1721{
1722 if (!page)
1723 return;
1724
a9777845 1725 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
8227b297
RK		 1726 /*
1727 * For b-tree node pages, this function may be called twice
1728 * or more because they might be split in a segment.
1729 */
a9777845
RK		 1730 if (PageDirty(page)) {
1731 /*
1732 * For pages holding split b-tree node buffers, dirty
1733 * flag on the buffers may be cleared discretely.
1734 * In that case, the page is once redirtied for
1735 * remaining buffers, and it must be cancelled if
1736 * all the buffers get cleaned later.
1737 */
1738 lock_page(page);
1739 if (nilfs_page_buffers_clean(page))
1740 __nilfs_clear_page_dirty(page);
1741 unlock_page(page);
1742 }
9ff05123 1743 return;
a9777845 1744 }
9ff05123
RK		 1745
1746 __nilfs_end_page_io(page, err);
1747}
1748
1749static void nilfs_clear_copied_buffers(struct list_head *list, int err)
1750{
1751 struct buffer_head *bh, *head;
1752 struct page *page;
1753
1754 while (!list_empty(list)) {
1755 bh = list_entry(list->next, struct buffer_head,
1756 b_assoc_buffers);
1757 page = bh->b_page;
1758 page_cache_get(page);
1759 head = bh = page_buffers(page);
1760 do {
1761 if (!list_empty(&bh->b_assoc_buffers)) {
1762 list_del_init(&bh->b_assoc_buffers);
1763 if (!err) {
1764 set_buffer_uptodate(bh);
1765 clear_buffer_dirty(bh);
27e6c7a3 1766 clear_buffer_delay(bh);
9ff05123
RK		 1767 clear_buffer_nilfs_volatile(bh);
1768 }
1769 brelse(bh); /* for b_assoc_buffers */
1770 }
1771 } while ((bh = bh->b_this_page) != head);
1772
1773 __nilfs_end_page_io(page, err);
1774 page_cache_release(page);
1775 }
1776}
1777
a694291a 1778static void nilfs_abort_logs(struct list_head *logs, struct page *failed_page,
1e2b68bf 1779 int err)
9ff05123
RK		 1780{
1781 struct nilfs_segment_buffer *segbuf;
1782 struct page *bd_page = NULL, *fs_page = NULL;
a694291a 1783 struct buffer_head *bh;
9ff05123 1784
a694291a
RK		 1785 if (list_empty(logs))
1786 return;
9ff05123 1787
a694291a 1788 list_for_each_entry(segbuf, logs, sb_list) {
9ff05123
RK		 1789 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1790 b_assoc_buffers) {
1791 if (bh->b_page != bd_page) {
1792 if (bd_page)
1793 end_page_writeback(bd_page);
1794 bd_page = bh->b_page;
1795 }
1796 }
1797
1798 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1799 b_assoc_buffers) {
1e2b68bf 1800 if (bh == segbuf->sb_super_root) {
9ff05123
RK		 1801 if (bh->b_page != bd_page) {
1802 end_page_writeback(bd_page);
1803 bd_page = bh->b_page;
1804 }
1805 break;
1806 }
1807 if (bh->b_page != fs_page) {
1808 nilfs_end_page_io(fs_page, err);
8227b297 1809 if (fs_page && fs_page == failed_page)
a694291a 1810 return;
9ff05123
RK		 1811 fs_page = bh->b_page;
1812 }
1813 }
1814 }
1815 if (bd_page)
1816 end_page_writeback(bd_page);
1817
1818 nilfs_end_page_io(fs_page, err);
a694291a
RK		 1819}
1820
1821static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1822 struct the_nilfs *nilfs, int err)
1823{
1824 LIST_HEAD(logs);
1825 int ret;
1826
1827 list_splice_tail_init(&sci->sc_write_logs, &logs);
1828 ret = nilfs_wait_on_logs(&logs);
1e2b68bf 1829 nilfs_abort_logs(&logs, NULL, ret ? : err);
a694291a
RK		 1830
1831 list_splice_tail_init(&sci->sc_segbufs, &logs);
1832 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1833 nilfs_free_incomplete_logs(&logs, nilfs);
9ff05123 1834 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err);
a694291a
RK		 1835
1836 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1837 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1838 sci->sc_freesegs,
1839 sci->sc_nfreesegs,
1840 NULL);
1841 WARN_ON(ret); /* do not happen */
1842 }
1843
1844 nilfs_destroy_logs(&logs);
9ff05123
RK		 1845}
1846
1847static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1848 struct nilfs_segment_buffer *segbuf)
1849{
1850 nilfs->ns_segnum = segbuf->sb_segnum;
1851 nilfs->ns_nextnum = segbuf->sb_nextnum;
1852 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1853 + segbuf->sb_sum.nblocks;
1854 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1855 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1856}
1857
1858static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1859{
1860 struct nilfs_segment_buffer *segbuf;
1861 struct page *bd_page = NULL, *fs_page = NULL;
e605f0a7 1862 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
1e2b68bf 1863 int update_sr = false;
9ff05123 1864
a694291a 1865 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
9ff05123
RK		 1866 struct buffer_head *bh;
1867
1868 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1869 b_assoc_buffers) {
1870 set_buffer_uptodate(bh);
1871 clear_buffer_dirty(bh);
1872 if (bh->b_page != bd_page) {
1873 if (bd_page)
1874 end_page_writeback(bd_page);
1875 bd_page = bh->b_page;
1876 }
1877 }
1878 /*
1879 * We assume that the buffers which belong to the same page
1880 * continue over the buffer list.
1881 * Under this assumption, the last BHs of pages is
1882 * identifiable by the discontinuity of bh->b_page
1883 * (page != fs_page).
1884 *
1885 * For B-tree node blocks, however, this assumption is not
1886 * guaranteed. The cleanup code of B-tree node pages needs
1887 * special care.
1888 */
1889 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1890 b_assoc_buffers) {
1891 set_buffer_uptodate(bh);
1892 clear_buffer_dirty(bh);
27e6c7a3 1893 clear_buffer_delay(bh);
9ff05123 1894 clear_buffer_nilfs_volatile(bh);
b1f6a4f2 1895 clear_buffer_nilfs_redirected(bh);
1e2b68bf 1896 if (bh == segbuf->sb_super_root) {
9ff05123
RK		 1897 if (bh->b_page != bd_page) {
1898 end_page_writeback(bd_page);
1899 bd_page = bh->b_page;
1900 }
1e2b68bf 1901 update_sr = true;
9ff05123
RK		 1902 break;
1903 }
1904 if (bh->b_page != fs_page) {
1905 nilfs_end_page_io(fs_page, 0);
1906 fs_page = bh->b_page;
1907 }
1908 }
1909
4762077c
RK		 1910 if (!nilfs_segbuf_simplex(segbuf)) {
1911 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
9ff05123
RK		 1912 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1913 sci->sc_lseg_stime = jiffies;
1914 }
4762077c 1915 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
9ff05123
RK		 1916 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1917 }
1918 }
1919 /*
1920 * Since pages may continue over multiple segment buffers,
1921 * end of the last page must be checked outside of the loop.
1922 */
1923 if (bd_page)
1924 end_page_writeback(bd_page);
1925
1926 nilfs_end_page_io(fs_page, 0);
1927
1928 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0);
1929
1930 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1931
c1c1d709 1932 if (nilfs_doing_gc())
9ff05123 1933 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
c1c1d709 1934 else
9ff05123 1935 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
9ff05123
RK		 1936
1937 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1938
a694291a 1939 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
9ff05123
RK		 1940 nilfs_set_next_segment(nilfs, segbuf);
1941
1942 if (update_sr) {
1943 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
e339ad31 1944 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
9ff05123 1945
c96fa464 1946 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
9ff05123
RK		 1947 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1948 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
a694291a 1949 nilfs_segctor_clear_metadata_dirty(sci);
9ff05123
RK		 1950 } else
1951 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1952}
1953
a694291a
RK		 1954static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1955{
1956 int ret;
1957
1958 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1959 if (!ret) {
1960 nilfs_segctor_complete_write(sci);
1961 nilfs_destroy_logs(&sci->sc_write_logs);
1962 }
1963 return ret;
1964}
1965
9ff05123
RK		 1966static int nilfs_segctor_check_in_files(struct nilfs_sc_info *sci,
1967 struct nilfs_sb_info *sbi)
1968{
1969 struct nilfs_inode_info *ii, *n;
e912a5b6 1970 struct inode *ifile = sci->sc_root->ifile;
9ff05123
RK		 1971
1972 spin_lock(&sbi->s_inode_lock);
1973 retry:
1974 list_for_each_entry_safe(ii, n, &sbi->s_dirty_files, i_dirty) {
1975 if (!ii->i_bh) {
1976 struct buffer_head *ibh;
1977 int err;
1978
1979 spin_unlock(&sbi->s_inode_lock);
1980 err = nilfs_ifile_get_inode_block(
e912a5b6 1981 ifile, ii->vfs_inode.i_ino, &ibh);
9ff05123
RK		 1982 if (unlikely(err)) {
1983 nilfs_warning(sbi->s_super, __func__,
1984 "failed to get inode block.\n");
1985 return err;
1986 }
1987 nilfs_mdt_mark_buffer_dirty(ibh);
e912a5b6 1988 nilfs_mdt_mark_dirty(ifile);
9ff05123
RK		 1989 spin_lock(&sbi->s_inode_lock);
1990 if (likely(!ii->i_bh))
1991 ii->i_bh = ibh;
1992 else
1993 brelse(ibh);
1994 goto retry;
1995 }
9ff05123
RK		 1996
1997 clear_bit(NILFS_I_QUEUED, &ii->i_state);
1998 set_bit(NILFS_I_BUSY, &ii->i_state);
1999 list_del(&ii->i_dirty);
2000 list_add_tail(&ii->i_dirty, &sci->sc_dirty_files);
2001 }
2002 spin_unlock(&sbi->s_inode_lock);
2003
9ff05123
RK		 2004 return 0;
2005}
2006
2007static void nilfs_segctor_check_out_files(struct nilfs_sc_info *sci,
2008 struct nilfs_sb_info *sbi)
2009{
2010 struct nilfs_transaction_info *ti = current->journal_info;
2011 struct nilfs_inode_info *ii, *n;
9ff05123
RK		 2012
2013 spin_lock(&sbi->s_inode_lock);
2014 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2015 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
6c43f410 2016 test_bit(NILFS_I_DIRTY, &ii->i_state))
9ff05123 2017 continue;
6c43f410 2018
9ff05123
RK		 2019 clear_bit(NILFS_I_BUSY, &ii->i_state);
2020 brelse(ii->i_bh);
2021 ii->i_bh = NULL;
2022 list_del(&ii->i_dirty);
2023 list_add_tail(&ii->i_dirty, &ti->ti_garbage);
2024 }
2025 spin_unlock(&sbi->s_inode_lock);
2026}
2027
9ff05123
RK		 2028/*
2029 * Main procedure of segment constructor
2030 */
2031static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2032{
2033 struct nilfs_sb_info *sbi = sci->sc_sbi;
2034 struct the_nilfs *nilfs = sbi->s_nilfs;
2035 struct page *failed_page;
1e2b68bf 2036 int err;
9ff05123
RK		 2037
2038 sci->sc_stage.scnt = NILFS_ST_INIT;
6c43f410 2039 sci->sc_cno = nilfs->ns_cno;
9ff05123
RK		 2040
2041 err = nilfs_segctor_check_in_files(sci, sbi);
2042 if (unlikely(err))
2043 goto out;
2044
e912a5b6 2045 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
9ff05123
RK		 2046 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2047
2048 if (nilfs_segctor_clean(sci))
2049 goto out;
2050
2051 do {
2052 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2053
2054 err = nilfs_segctor_begin_construction(sci, nilfs);
2055 if (unlikely(err))
2056 goto out;
2057
2058 /* Update time stamp */
2059 sci->sc_seg_ctime = get_seconds();
2060
2061 err = nilfs_segctor_collect(sci, nilfs, mode);
2062 if (unlikely(err))
2063 goto failed;
2064
9ff05123
RK		 2065 /* Avoid empty segment */
2066 if (sci->sc_stage.scnt == NILFS_ST_DONE &&
4762077c 2067 nilfs_segbuf_empty(sci->sc_curseg)) {
a694291a 2068 nilfs_segctor_abort_construction(sci, nilfs, 1);
9ff05123
RK		 2069 goto out;
2070 }
2071
2072 err = nilfs_segctor_assign(sci, mode);
2073 if (unlikely(err))
2074 goto failed;
2075
9ff05123 2076 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
e912a5b6 2077 nilfs_segctor_fill_in_file_bmap(sci);
9ff05123 2078
1e2b68bf
RK		 2079 if (mode == SC_LSEG_SR &&
2080 sci->sc_stage.scnt >= NILFS_ST_CPFILE) {
9ff05123
RK		 2081 err = nilfs_segctor_fill_in_checkpoint(sci);
2082 if (unlikely(err))
a694291a 2083 goto failed_to_write;
9ff05123
RK		 2084
2085 nilfs_segctor_fill_in_super_root(sci, nilfs);
2086 }
2087 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2088
2089 /* Write partial segments */
2090 err = nilfs_segctor_prepare_write(sci, &failed_page);
a694291a 2091 if (err) {
1e2b68bf 2092 nilfs_abort_logs(&sci->sc_segbufs, failed_page, err);
9ff05123 2093 goto failed_to_write;
a694291a 2094 }
aaed1d5b
RK		 2095
2096 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2097 nilfs->ns_crc_seed);
9ff05123 2098
9c965bac 2099 err = nilfs_segctor_write(sci, nilfs);
9ff05123
RK		 2100 if (unlikely(err))
2101 goto failed_to_write;
2102
a694291a
RK		 2103 if (sci->sc_stage.scnt == NILFS_ST_DONE ||
2104 nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) {
2105 /*
2106 * At this point, we avoid double buffering
2107 * for blocksize < pagesize because page dirty
2108 * flag is turned off during write and dirty
2109 * buffers are not properly collected for
2110 * pages crossing over segments.
2111 */
2112 err = nilfs_segctor_wait(sci);
2113 if (err)
2114 goto failed_to_write;
2115 }
9ff05123
RK		 2116 } while (sci->sc_stage.scnt != NILFS_ST_DONE);
2117
9ff05123 2118 out:
9ff05123
RK		 2119 nilfs_segctor_check_out_files(sci, sbi);
2120 return err;
2121
2122 failed_to_write:
9ff05123
RK		 2123 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2124 nilfs_redirty_inodes(&sci->sc_dirty_files);
9ff05123
RK		 2125
2126 failed:
2127 if (nilfs_doing_gc())
2128 nilfs_redirty_inodes(&sci->sc_gc_inodes);
a694291a 2129 nilfs_segctor_abort_construction(sci, nilfs, err);
9ff05123
RK		 2130 goto out;
2131}
2132
2133/**
9ccf56c1 2134 * nilfs_segctor_start_timer - set timer of background write
9ff05123
RK		 2135 * @sci: nilfs_sc_info
2136 *
2137 * If the timer has already been set, it ignores the new request.
2138 * This function MUST be called within a section locking the segment
2139 * semaphore.
2140 */
2141static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2142{
2143 spin_lock(&sci->sc_state_lock);
fdce895e
LH		 2144 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2145 sci->sc_timer.expires = jiffies + sci->sc_interval;
2146 add_timer(&sci->sc_timer);
9ff05123
RK		 2147 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2148 }
2149 spin_unlock(&sci->sc_state_lock);
2150}
2151
2152static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2153{
2154 spin_lock(&sci->sc_state_lock);
2155 if (!(sci->sc_flush_request & (1 << bn))) {
2156 unsigned long prev_req = sci->sc_flush_request;
2157
2158 sci->sc_flush_request |= (1 << bn);
2159 if (!prev_req)
2160 wake_up(&sci->sc_wait_daemon);
2161 }
2162 spin_unlock(&sci->sc_state_lock);
2163}
2164
2165/**
2166 * nilfs_flush_segment - trigger a segment construction for resource control
2167 * @sb: super block
2168 * @ino: inode number of the file to be flushed out.
2169 */
2170void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2171{
2172 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2173 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2174
2175 if (!sci || nilfs_doing_construction())
2176 return;
2177 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2178 /* assign bit 0 to data files */
2179}
2180
9ff05123
RK		 2181struct nilfs_segctor_wait_request {
2182 wait_queue_t wq;
2183 __u32 seq;
2184 int err;
2185 atomic_t done;
2186};
2187
2188static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2189{
2190 struct nilfs_segctor_wait_request wait_req;
2191 int err = 0;
2192
2193 spin_lock(&sci->sc_state_lock);
2194 init_wait(&wait_req.wq);
2195 wait_req.err = 0;
2196 atomic_set(&wait_req.done, 0);
2197 wait_req.seq = ++sci->sc_seq_request;
2198 spin_unlock(&sci->sc_state_lock);
2199
2200 init_waitqueue_entry(&wait_req.wq, current);
2201 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2202 set_current_state(TASK_INTERRUPTIBLE);
2203 wake_up(&sci->sc_wait_daemon);
2204
2205 for (;;) {
2206 if (atomic_read(&wait_req.done)) {
2207 err = wait_req.err;
2208 break;
2209 }
2210 if (!signal_pending(current)) {
2211 schedule();
2212 continue;
2213 }
2214 err = -ERESTARTSYS;
2215 break;
2216 }
2217 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2218 return err;
2219}
2220
2221static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2222{
2223 struct nilfs_segctor_wait_request *wrq, *n;
2224 unsigned long flags;
2225
2226 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2227 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
2228 wq.task_list) {
2229 if (!atomic_read(&wrq->done) &&
2230 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2231 wrq->err = err;
2232 atomic_set(&wrq->done, 1);
2233 }
2234 if (atomic_read(&wrq->done)) {
2235 wrq->wq.func(&wrq->wq,
2236 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2237 0, NULL);
2238 }
2239 }
2240 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2241}
2242
2243/**
2244 * nilfs_construct_segment - construct a logical segment
2245 * @sb: super block
2246 *
2247 * Return Value: On success, 0 is retured. On errors, one of the following
2248 * negative error code is returned.
2249 *
2250 * %-EROFS - Read only filesystem.
2251 *
2252 * %-EIO - I/O error
2253 *
2254 * %-ENOSPC - No space left on device (only in a panic state).
2255 *
2256 * %-ERESTARTSYS - Interrupted.
2257 *
2258 * %-ENOMEM - Insufficient memory available.
2259 */
2260int nilfs_construct_segment(struct super_block *sb)
2261{
2262 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2263 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2264 struct nilfs_transaction_info *ti;
2265 int err;
2266
2267 if (!sci)
2268 return -EROFS;
2269
2270 /* A call inside transactions causes a deadlock. */
2271 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2272
2273 err = nilfs_segctor_sync(sci);
2274 return err;
2275}
2276
2277/**
2278 * nilfs_construct_dsync_segment - construct a data-only logical segment
2279 * @sb: super block
f30bf3e4
RK		 2280 * @inode: inode whose data blocks should be written out
2281 * @start: start byte offset
2282 * @end: end byte offset (inclusive)
9ff05123
RK		 2283 *
2284 * Return Value: On success, 0 is retured. On errors, one of the following
2285 * negative error code is returned.
2286 *
2287 * %-EROFS - Read only filesystem.
2288 *
2289 * %-EIO - I/O error
2290 *
2291 * %-ENOSPC - No space left on device (only in a panic state).
2292 *
2293 * %-ERESTARTSYS - Interrupted.
2294 *
2295 * %-ENOMEM - Insufficient memory available.
2296 */
f30bf3e4
RK		 2297int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2298 loff_t start, loff_t end)
9ff05123
RK		 2299{
2300 struct nilfs_sb_info *sbi = NILFS_SB(sb);
3b2ce58b 2301 struct the_nilfs *nilfs = sbi->s_nilfs;
9ff05123
RK		 2302 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2303 struct nilfs_inode_info *ii;
2304 struct nilfs_transaction_info ti;
2305 int err = 0;
2306
2307 if (!sci)
2308 return -EROFS;
2309
2310 nilfs_transaction_lock(sbi, &ti, 0);
2311
2312 ii = NILFS_I(inode);
2313 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) ||
3b2ce58b 2314 nilfs_test_opt(nilfs, STRICT_ORDER) ||
9ff05123 2315 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
3b2ce58b 2316 nilfs_discontinued(nilfs)) {
9ff05123
RK		 2317 nilfs_transaction_unlock(sbi);
2318 err = nilfs_segctor_sync(sci);
2319 return err;
2320 }
2321
2322 spin_lock(&sbi->s_inode_lock);
2323 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2324 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2325 spin_unlock(&sbi->s_inode_lock);
2326 nilfs_transaction_unlock(sbi);
2327 return 0;
2328 }
2329 spin_unlock(&sbi->s_inode_lock);
f30bf3e4
RK		 2330 sci->sc_dsync_inode = ii;
2331 sci->sc_dsync_start = start;
2332 sci->sc_dsync_end = end;
9ff05123
RK		 2333
2334 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2335
2336 nilfs_transaction_unlock(sbi);
2337 return err;
2338}
2339
9ff05123
RK		 2340#define FLUSH_FILE_BIT (0x1) /* data file only */
2341#define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */
2342
dcd76186
RK		 2343/**
2344 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2345 * @sci: segment constructor object
2346 */
2347static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
9ff05123 2348{
9ff05123 2349 spin_lock(&sci->sc_state_lock);
dcd76186 2350 sci->sc_seq_accepted = sci->sc_seq_request;
9ff05123 2351 spin_unlock(&sci->sc_state_lock);
fdce895e 2352 del_timer_sync(&sci->sc_timer);
9ff05123
RK		 2353}
2354
dcd76186
RK		 2355/**
2356 * nilfs_segctor_notify - notify the result of request to caller threads
2357 * @sci: segment constructor object
2358 * @mode: mode of log forming
2359 * @err: error code to be notified
2360 */
2361static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
9ff05123
RK		 2362{
2363 /* Clear requests (even when the construction failed) */
2364 spin_lock(&sci->sc_state_lock);
2365
dcd76186 2366 if (mode == SC_LSEG_SR) {
aeda7f63 2367 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
dcd76186
RK		 2368 sci->sc_seq_done = sci->sc_seq_accepted;
2369 nilfs_segctor_wakeup(sci, err);
9ff05123 2370 sci->sc_flush_request = 0;
aeda7f63 2371 } else {
dcd76186 2372 if (mode == SC_FLUSH_FILE)
aeda7f63 2373 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
dcd76186 2374 else if (mode == SC_FLUSH_DAT)
aeda7f63
RK		 2375 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2376
2377 /* re-enable timer if checkpoint creation was not done */
fdce895e
LH		 2378 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2379 time_before(jiffies, sci->sc_timer.expires))
2380 add_timer(&sci->sc_timer);
aeda7f63 2381 }
9ff05123
RK		 2382 spin_unlock(&sci->sc_state_lock);
2383}
2384
dcd76186
RK		 2385/**
2386 * nilfs_segctor_construct - form logs and write them to disk
2387 * @sci: segment constructor object
2388 * @mode: mode of log forming
2389 */
2390static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
9ff05123
RK		 2391{
2392 struct nilfs_sb_info *sbi = sci->sc_sbi;
2393 struct the_nilfs *nilfs = sbi->s_nilfs;
d26493b6 2394 struct nilfs_super_block **sbp;
9ff05123
RK		 2395 int err = 0;
2396
dcd76186
RK		 2397 nilfs_segctor_accept(sci);
2398
9ff05123 2399 if (nilfs_discontinued(nilfs))
dcd76186
RK		 2400 mode = SC_LSEG_SR;
2401 if (!nilfs_segctor_confirm(sci))
2402 err = nilfs_segctor_do_construct(sci, mode);
2403
9ff05123 2404 if (likely(!err)) {
dcd76186 2405 if (mode != SC_FLUSH_DAT)
9ff05123
RK		 2406 atomic_set(&nilfs->ns_ndirtyblks, 0);
2407 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2408 nilfs_discontinued(nilfs)) {
2409 down_write(&nilfs->ns_sem);
d26493b6 2410 err = -EIO;
b2ac86e1
JS		 2411 sbp = nilfs_prepare_super(sbi,
2412 nilfs_sb_will_flip(nilfs));
2413 if (likely(sbp)) {
2414 nilfs_set_log_cursor(sbp[0], nilfs);
2415 err = nilfs_commit_super(sbi, NILFS_SB_COMMIT);
2416 }
9ff05123
RK		 2417 up_write(&nilfs->ns_sem);
2418 }
2419 }
dcd76186
RK		 2420
2421 nilfs_segctor_notify(sci, mode, err);
9ff05123
RK		 2422 return err;
2423}
2424
2425static void nilfs_construction_timeout(unsigned long data)
2426{
2427 struct task_struct *p = (struct task_struct *)data;
2428 wake_up_process(p);
2429}
2430
2431static void
2432nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2433{
2434 struct nilfs_inode_info *ii, *n;
2435
2436 list_for_each_entry_safe(ii, n, head, i_dirty) {
2437 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2438 continue;
9ff05123 2439 list_del_init(&ii->i_dirty);
263d90ce 2440 iput(&ii->vfs_inode);
9ff05123
RK		 2441 }
2442}
2443
4f6b8288
RK		 2444int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2445 void **kbufs)
9ff05123
RK		 2446{
2447 struct nilfs_sb_info *sbi = NILFS_SB(sb);
2448 struct nilfs_sc_info *sci = NILFS_SC(sbi);
2449 struct the_nilfs *nilfs = sbi->s_nilfs;
2450 struct nilfs_transaction_info ti;
9ff05123
RK		 2451 int err;
2452
2453 if (unlikely(!sci))
2454 return -EROFS;
2455
2456 nilfs_transaction_lock(sbi, &ti, 1);
2457
c1c1d709 2458 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
9ff05123
RK		 2459 if (unlikely(err))
2460 goto out_unlock;
071cb4b8 2461
4f6b8288 2462 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
c1c1d709
RK		 2463 if (unlikely(err)) {
2464 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
9ff05123 2465 goto out_unlock;
c1c1d709 2466 }
9ff05123 2467
071cb4b8
RK		 2468 sci->sc_freesegs = kbufs[4];
2469 sci->sc_nfreesegs = argv[4].v_nmembs;
0935db74 2470 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
9ff05123
RK		 2471
2472 for (;;) {
dcd76186 2473 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
9ff05123 2474 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
9ff05123
RK		 2475
2476 if (likely(!err))
2477 break;
2478
2479 nilfs_warning(sb, __func__,
2480 "segment construction failed. (err=%d)", err);
2481 set_current_state(TASK_INTERRUPTIBLE);
2482 schedule_timeout(sci->sc_interval);
2483 }
3b2ce58b 2484 if (nilfs_test_opt(nilfs, DISCARD)) {
e902ec99
JS		 2485 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2486 sci->sc_nfreesegs);
2487 if (ret) {
2488 printk(KERN_WARNING
2489 "NILFS warning: error %d on discard request, "
2490 "turning discards off for the device\n", ret);
3b2ce58b 2491 nilfs_clear_opt(nilfs, DISCARD);
e902ec99
JS		 2492 }
2493 }
9ff05123
RK		 2494
2495 out_unlock:
071cb4b8
RK		 2496 sci->sc_freesegs = NULL;
2497 sci->sc_nfreesegs = 0;
c1c1d709 2498 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
9ff05123
RK		 2499 nilfs_transaction_unlock(sbi);
2500 return err;
2501}
2502
2503static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2504{
2505 struct nilfs_sb_info *sbi = sci->sc_sbi;
2506 struct nilfs_transaction_info ti;
9ff05123
RK		 2507
2508 nilfs_transaction_lock(sbi, &ti, 0);
dcd76186 2509 nilfs_segctor_construct(sci, mode);
9ff05123
RK		 2510
2511 /*
2512 * Unclosed segment should be retried. We do this using sc_timer.
2513 * Timeout of sc_timer will invoke complete construction which leads
2514 * to close the current logical segment.
2515 */
2516 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2517 nilfs_segctor_start_timer(sci);
2518
2519 nilfs_transaction_unlock(sbi);
2520}
2521
2522static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2523{
2524 int mode = 0;
2525 int err;
2526
2527 spin_lock(&sci->sc_state_lock);
2528 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2529 SC_FLUSH_DAT : SC_FLUSH_FILE;
2530 spin_unlock(&sci->sc_state_lock);
2531
2532 if (mode) {
2533 err = nilfs_segctor_do_construct(sci, mode);
2534
2535 spin_lock(&sci->sc_state_lock);
2536 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2537 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2538 spin_unlock(&sci->sc_state_lock);
2539 }
2540 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2541}
2542
2543static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2544{
2545 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2546 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2547 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2548 return SC_FLUSH_FILE;
2549 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2550 return SC_FLUSH_DAT;
2551 }
2552 return SC_LSEG_SR;
2553}
2554
2555/**
2556 * nilfs_segctor_thread - main loop of the segment constructor thread.
2557 * @arg: pointer to a struct nilfs_sc_info.
2558 *
2559 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2560 * to execute segment constructions.
2561 */
2562static int nilfs_segctor_thread(void *arg)
2563{
2564 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
e605f0a7 2565 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs;
9ff05123
RK		 2566 int timeout = 0;
2567
fdce895e
LH		 2568 sci->sc_timer.data = (unsigned long)current;
2569 sci->sc_timer.function = nilfs_construction_timeout;
9ff05123
RK		 2570
2571 /* start sync. */
2572 sci->sc_task = current;
2573 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2574 printk(KERN_INFO
2575 "segctord starting. Construction interval = %lu seconds, "
2576 "CP frequency < %lu seconds\n",
2577 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2578
2579 spin_lock(&sci->sc_state_lock);
2580 loop:
2581 for (;;) {
2582 int mode;
2583
2584 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2585 goto end_thread;
2586
2587 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2588 mode = SC_LSEG_SR;
2589 else if (!sci->sc_flush_request)
2590 break;
2591 else
2592 mode = nilfs_segctor_flush_mode(sci);
2593
2594 spin_unlock(&sci->sc_state_lock);
2595 nilfs_segctor_thread_construct(sci, mode);
2596 spin_lock(&sci->sc_state_lock);
2597 timeout = 0;
2598 }
2599
2600
2601 if (freezing(current)) {
2602 spin_unlock(&sci->sc_state_lock);
2603 refrigerator();
2604 spin_lock(&sci->sc_state_lock);
2605 } else {
2606 DEFINE_WAIT(wait);
2607 int should_sleep = 1;
2608
2609 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2610 TASK_INTERRUPTIBLE);
2611
2612 if (sci->sc_seq_request != sci->sc_seq_done)
2613 should_sleep = 0;
2614 else if (sci->sc_flush_request)
2615 should_sleep = 0;
2616 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2617 should_sleep = time_before(jiffies,
fdce895e 2618 sci->sc_timer.expires);
9ff05123
RK		 2619
2620 if (should_sleep) {
2621 spin_unlock(&sci->sc_state_lock);
2622 schedule();
2623 spin_lock(&sci->sc_state_lock);
2624 }
2625 finish_wait(&sci->sc_wait_daemon, &wait);
2626 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
fdce895e 2627 time_after_eq(jiffies, sci->sc_timer.expires));
e605f0a7
RK		 2628
2629 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
1dfa2710 2630 set_nilfs_discontinued(nilfs);
9ff05123
RK		 2631 }
2632 goto loop;
2633
2634 end_thread:
2635 spin_unlock(&sci->sc_state_lock);
9ff05123
RK		 2636
2637 /* end sync. */
2638 sci->sc_task = NULL;
2639 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2640 return 0;
2641}
2642
2643static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2644{
2645 struct task_struct *t;
2646
2647 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2648 if (IS_ERR(t)) {
2649 int err = PTR_ERR(t);
2650
2651 printk(KERN_ERR "NILFS: error %d creating segctord thread\n",
2652 err);
2653 return err;
2654 }
2655 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2656 return 0;
2657}
2658
2659static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
6b81e14e
JS		 2660 __acquires(&sci->sc_state_lock)
2661 __releases(&sci->sc_state_lock)
9ff05123
RK		 2662{
2663 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2664
2665 while (sci->sc_task) {
2666 wake_up(&sci->sc_wait_daemon);
2667 spin_unlock(&sci->sc_state_lock);
2668 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2669 spin_lock(&sci->sc_state_lock);
2670 }
2671}
2672
9ff05123
RK		 2673/*
2674 * Setup & clean-up functions
2675 */
e912a5b6
RK		 2676static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi,
2677 struct nilfs_root *root)
9ff05123
RK		 2678{
2679 struct nilfs_sc_info *sci;
2680
2681 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2682 if (!sci)
2683 return NULL;
2684
2685 sci->sc_sbi = sbi;
2686 sci->sc_super = sbi->s_super;
2687
e912a5b6
RK		 2688 nilfs_get_root(root);
2689 sci->sc_root = root;
2690
9ff05123
RK		 2691 init_waitqueue_head(&sci->sc_wait_request);
2692 init_waitqueue_head(&sci->sc_wait_daemon);
2693 init_waitqueue_head(&sci->sc_wait_task);
2694 spin_lock_init(&sci->sc_state_lock);
2695 INIT_LIST_HEAD(&sci->sc_dirty_files);
2696 INIT_LIST_HEAD(&sci->sc_segbufs);
a694291a 2697 INIT_LIST_HEAD(&sci->sc_write_logs);
9ff05123 2698 INIT_LIST_HEAD(&sci->sc_gc_inodes);
9ff05123 2699 INIT_LIST_HEAD(&sci->sc_copied_buffers);
fdce895e 2700 init_timer(&sci->sc_timer);
9ff05123
RK		 2701
2702 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2703 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2704 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2705
2706 if (sbi->s_interval)
2707 sci->sc_interval = sbi->s_interval;
2708 if (sbi->s_watermark)
2709 sci->sc_watermark = sbi->s_watermark;
2710 return sci;
2711}
2712
2713static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2714{
2715 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2716
2717 /* The segctord thread was stopped and its timer was removed.
2718 But some tasks remain. */
2719 do {
2720 struct nilfs_sb_info *sbi = sci->sc_sbi;
2721 struct nilfs_transaction_info ti;
9ff05123
RK		 2722
2723 nilfs_transaction_lock(sbi, &ti, 0);
dcd76186 2724 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
9ff05123
RK		 2725 nilfs_transaction_unlock(sbi);
2726
2727 } while (ret && retrycount-- > 0);
2728}
2729
2730/**
2731 * nilfs_segctor_destroy - destroy the segment constructor.
2732 * @sci: nilfs_sc_info
2733 *
2734 * nilfs_segctor_destroy() kills the segctord thread and frees
2735 * the nilfs_sc_info struct.
2736 * Caller must hold the segment semaphore.
2737 */
2738static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2739{
2740 struct nilfs_sb_info *sbi = sci->sc_sbi;
2741 int flag;
2742
2743 up_write(&sbi->s_nilfs->ns_segctor_sem);
2744
2745 spin_lock(&sci->sc_state_lock);
2746 nilfs_segctor_kill_thread(sci);
2747 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2748 || sci->sc_seq_request != sci->sc_seq_done);
2749 spin_unlock(&sci->sc_state_lock);
2750
3256a055 2751 if (flag || !nilfs_segctor_confirm(sci))
9ff05123
RK		 2752 nilfs_segctor_write_out(sci);
2753
1f5abe7e 2754 WARN_ON(!list_empty(&sci->sc_copied_buffers));
9ff05123
RK		 2755
2756 if (!list_empty(&sci->sc_dirty_files)) {
2757 nilfs_warning(sbi->s_super, __func__,
2758 "dirty file(s) after the final construction\n");
2759 nilfs_dispose_list(sbi, &sci->sc_dirty_files, 1);
2760 }
9ff05123 2761
1f5abe7e 2762 WARN_ON(!list_empty(&sci->sc_segbufs));
a694291a 2763 WARN_ON(!list_empty(&sci->sc_write_logs));
9ff05123 2764
e912a5b6
RK		 2765 nilfs_put_root(sci->sc_root);
2766
9ff05123
RK		 2767 down_write(&sbi->s_nilfs->ns_segctor_sem);
2768
fdce895e 2769 del_timer_sync(&sci->sc_timer);
9ff05123
RK		 2770 kfree(sci);
2771}
2772
2773/**
2774 * nilfs_attach_segment_constructor - attach a segment constructor
2775 * @sbi: nilfs_sb_info
e912a5b6 2776 * @root: root object of the current filesystem tree
9ff05123
RK		 2777 *
2778 * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info,
7a65004b 2779 * initializes it, and starts the segment constructor.
9ff05123
RK		 2780 *
2781 * Return Value: On success, 0 is returned. On error, one of the following
2782 * negative error code is returned.
2783 *
2784 * %-ENOMEM - Insufficient memory available.
2785 */
e912a5b6
RK		 2786int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi,
2787 struct nilfs_root *root)
9ff05123 2788{
9ff05123
RK		 2789 int err;
2790
fe5f171b
RK		 2791 if (NILFS_SC(sbi)) {
2792 /*
2793 * This happens if the filesystem was remounted
2794 * read/write after nilfs_error degenerated it into a
2795 * read-only mount.
2796 */
2797 nilfs_detach_segment_constructor(sbi);
2798 }
2799
e912a5b6 2800 sbi->s_sc_info = nilfs_segctor_new(sbi, root);
9ff05123
RK		 2801 if (!sbi->s_sc_info)
2802 return -ENOMEM;
2803
154ac5a8 2804 err = nilfs_segctor_start_thread(NILFS_SC(sbi));
9ff05123 2805 if (err) {
9ff05123
RK		 2806 kfree(sbi->s_sc_info);
2807 sbi->s_sc_info = NULL;
2808 }
2809 return err;
2810}
2811
2812/**
2813 * nilfs_detach_segment_constructor - destroy the segment constructor
2814 * @sbi: nilfs_sb_info
2815 *
2816 * nilfs_detach_segment_constructor() kills the segment constructor daemon,
2817 * frees the struct nilfs_sc_info, and destroy the dirty file list.
2818 */
2819void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi)
2820{
2821 struct the_nilfs *nilfs = sbi->s_nilfs;
2822 LIST_HEAD(garbage_list);
2823
2824 down_write(&nilfs->ns_segctor_sem);
2825 if (NILFS_SC(sbi)) {
2826 nilfs_segctor_destroy(NILFS_SC(sbi));
2827 sbi->s_sc_info = NULL;
2828 }
2829
2830 /* Force to free the list of dirty files */
2831 spin_lock(&sbi->s_inode_lock);
2832 if (!list_empty(&sbi->s_dirty_files)) {
2833 list_splice_init(&sbi->s_dirty_files, &garbage_list);
2834 nilfs_warning(sbi->s_super, __func__,
2835 "Non empty dirty list after the last "
2836 "segment construction\n");
2837 }
2838 spin_unlock(&sbi->s_inode_lock);
2839 up_write(&nilfs->ns_segctor_sem);
2840
2841 nilfs_dispose_list(sbi, &garbage_list, 1);
9ff05123 2842}
Linux 6.x block layer and io_uring tree(s)