1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * segment.c - NILFS segment constructor.
4 *
5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Ryusuke Konishi.
8 *
9 */
10
11 #include <linux/pagemap.h>
12 #include <linux/buffer_head.h>
13 #include <linux/writeback.h>
14 #include <linux/bitops.h>
15 #include <linux/bio.h>
16 #include <linux/completion.h>
17 #include <linux/blkdev.h>
18 #include <linux/backing-dev.h>
19 #include <linux/freezer.h>
20 #include <linux/kthread.h>
21 #include <linux/crc32.h>
22 #include <linux/pagevec.h>
23 #include <linux/slab.h>
24 #include <linux/sched/signal.h>
25
26 #include "nilfs.h"
27 #include "btnode.h"
28 #include "page.h"
29 #include "segment.h"
30 #include "sufile.h"
31 #include "cpfile.h"
32 #include "ifile.h"
33 #include "segbuf.h"
34
35
36 /*
37 * Segment constructor
38 */
39 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */
40
41 #define SC_MAX_SEGDELTA 64 /*
42 * Upper limit of the number of segments
43 * appended in collection retry loop
44 */
45
46 /* Construction mode */
47 enum {
48 SC_LSEG_SR = 1, /* Make a logical segment having a super root */
49 SC_LSEG_DSYNC, /*
50 * Flush data blocks of a given file and make
51 * a logical segment without a super root.
52 */
53 SC_FLUSH_FILE, /*
54 * Flush data files, leads to segment writes without
55 * creating a checkpoint.
56 */
57 SC_FLUSH_DAT, /*
58 * Flush DAT file. This also creates segments
59 * without a checkpoint.
60 */
61 };
62
63 /* Stage numbers of dirty block collection */
64 enum {
65 NILFS_ST_INIT = 0,
66 NILFS_ST_GC, /* Collecting dirty blocks for GC */
67 NILFS_ST_FILE,
68 NILFS_ST_IFILE,
69 NILFS_ST_CPFILE,
70 NILFS_ST_SUFILE,
71 NILFS_ST_DAT,
72 NILFS_ST_SR, /* Super root */
73 NILFS_ST_DSYNC, /* Data sync blocks */
74 NILFS_ST_DONE,
75 };
76
77 #define CREATE_TRACE_POINTS
78 #include <trace/events/nilfs2.h>
79
80 /*
81 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are
82 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of
83 * the variable must use them because transition of stage count must involve
84 * trace events (trace_nilfs2_collection_stage_transition).
85 *
86 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't
87 * produce tracepoint events. It is provided just for making the intention
88 * clear.
89 */
nilfs_sc_cstage_inc(struct nilfs_sc_info * sci)90 static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci)
91 {
92 sci->sc_stage.scnt++;
93 trace_nilfs2_collection_stage_transition(sci);
94 }
95
nilfs_sc_cstage_set(struct nilfs_sc_info * sci,int next_scnt)96 static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt)
97 {
98 sci->sc_stage.scnt = next_scnt;
99 trace_nilfs2_collection_stage_transition(sci);
100 }
101
nilfs_sc_cstage_get(struct nilfs_sc_info * sci)102 static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci)
103 {
104 return sci->sc_stage.scnt;
105 }
106
107 /* State flags of collection */
108 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */
109 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */
110 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */
111 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED)
112
113 /* Operations depending on the construction mode and file type */
114 struct nilfs_sc_operations {
115 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *,
116 struct inode *);
117 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *,
118 struct inode *);
119 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *,
120 struct inode *);
121 void (*write_data_binfo)(struct nilfs_sc_info *,
122 struct nilfs_segsum_pointer *,
123 union nilfs_binfo *);
124 void (*write_node_binfo)(struct nilfs_sc_info *,
125 struct nilfs_segsum_pointer *,
126 union nilfs_binfo *);
127 };
128
129 /*
130 * Other definitions
131 */
132 static void nilfs_segctor_start_timer(struct nilfs_sc_info *);
133 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int);
134 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *);
135 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int);
136
137 #define nilfs_cnt32_gt(a, b) \
138 (typecheck(__u32, a) && typecheck(__u32, b) && \
139 ((__s32)(b) - (__s32)(a) < 0))
140 #define nilfs_cnt32_ge(a, b) \
141 (typecheck(__u32, a) && typecheck(__u32, b) && \
142 ((__s32)(a) - (__s32)(b) >= 0))
143 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a)
144 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a)
145
nilfs_prepare_segment_lock(struct super_block * sb,struct nilfs_transaction_info * ti)146 static int nilfs_prepare_segment_lock(struct super_block *sb,
147 struct nilfs_transaction_info *ti)
148 {
149 struct nilfs_transaction_info *cur_ti = current->journal_info;
150 void *save = NULL;
151
152 if (cur_ti) {
153 if (cur_ti->ti_magic == NILFS_TI_MAGIC)
154 return ++cur_ti->ti_count;
155
156 /*
157 * If journal_info field is occupied by other FS,
158 * it is saved and will be restored on
159 * nilfs_transaction_commit().
160 */
161 nilfs_warn(sb, "journal info from a different FS");
162 save = current->journal_info;
163 }
164 if (!ti) {
165 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS);
166 if (!ti)
167 return -ENOMEM;
168 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC;
169 } else {
170 ti->ti_flags = 0;
171 }
172 ti->ti_count = 0;
173 ti->ti_save = save;
174 ti->ti_magic = NILFS_TI_MAGIC;
175 current->journal_info = ti;
176 return 0;
177 }
178
179 /**
180 * nilfs_transaction_begin - start indivisible file operations.
181 * @sb: super block
182 * @ti: nilfs_transaction_info
183 * @vacancy_check: flags for vacancy rate checks
184 *
185 * nilfs_transaction_begin() acquires a reader/writer semaphore, called
186 * the segment semaphore, to make a segment construction and write tasks
187 * exclusive. The function is used with nilfs_transaction_commit() in pairs.
188 * The region enclosed by these two functions can be nested. To avoid a
189 * deadlock, the semaphore is only acquired or released in the outermost call.
190 *
191 * This function allocates a nilfs_transaction_info struct to keep context
192 * information on it. It is initialized and hooked onto the current task in
193 * the outermost call. If a pre-allocated struct is given to @ti, it is used
194 * instead; otherwise a new struct is assigned from a slab.
195 *
196 * When @vacancy_check flag is set, this function will check the amount of
197 * free space, and will wait for the GC to reclaim disk space if low capacity.
198 *
199 * Return Value: On success, 0 is returned. On error, one of the following
200 * negative error code is returned.
201 *
202 * %-ENOMEM - Insufficient memory available.
203 *
204 * %-ENOSPC - No space left on device
205 */
nilfs_transaction_begin(struct super_block * sb,struct nilfs_transaction_info * ti,int vacancy_check)206 int nilfs_transaction_begin(struct super_block *sb,
207 struct nilfs_transaction_info *ti,
208 int vacancy_check)
209 {
210 struct the_nilfs *nilfs;
211 int ret = nilfs_prepare_segment_lock(sb, ti);
212 struct nilfs_transaction_info *trace_ti;
213
214 if (unlikely(ret < 0))
215 return ret;
216 if (ret > 0) {
217 trace_ti = current->journal_info;
218
219 trace_nilfs2_transaction_transition(sb, trace_ti,
220 trace_ti->ti_count, trace_ti->ti_flags,
221 TRACE_NILFS2_TRANSACTION_BEGIN);
222 return 0;
223 }
224
225 sb_start_intwrite(sb);
226
227 nilfs = sb->s_fs_info;
228 down_read(&nilfs->ns_segctor_sem);
229 if (vacancy_check && nilfs_near_disk_full(nilfs)) {
230 up_read(&nilfs->ns_segctor_sem);
231 ret = -ENOSPC;
232 goto failed;
233 }
234
235 trace_ti = current->journal_info;
236 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count,
237 trace_ti->ti_flags,
238 TRACE_NILFS2_TRANSACTION_BEGIN);
239 return 0;
240
241 failed:
242 ti = current->journal_info;
243 current->journal_info = ti->ti_save;
244 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
245 kmem_cache_free(nilfs_transaction_cachep, ti);
246 sb_end_intwrite(sb);
247 return ret;
248 }
249
250 /**
251 * nilfs_transaction_commit - commit indivisible file operations.
252 * @sb: super block
253 *
254 * nilfs_transaction_commit() releases the read semaphore which is
255 * acquired by nilfs_transaction_begin(). This is only performed
256 * in outermost call of this function. If a commit flag is set,
257 * nilfs_transaction_commit() sets a timer to start the segment
258 * constructor. If a sync flag is set, it starts construction
259 * directly.
260 */
nilfs_transaction_commit(struct super_block * sb)261 int nilfs_transaction_commit(struct super_block *sb)
262 {
263 struct nilfs_transaction_info *ti = current->journal_info;
264 struct the_nilfs *nilfs = sb->s_fs_info;
265 int err = 0;
266
267 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
268 ti->ti_flags |= NILFS_TI_COMMIT;
269 if (ti->ti_count > 0) {
270 ti->ti_count--;
271 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
272 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
273 return 0;
274 }
275 if (nilfs->ns_writer) {
276 struct nilfs_sc_info *sci = nilfs->ns_writer;
277
278 if (ti->ti_flags & NILFS_TI_COMMIT)
279 nilfs_segctor_start_timer(sci);
280 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark)
281 nilfs_segctor_do_flush(sci, 0);
282 }
283 up_read(&nilfs->ns_segctor_sem);
284 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
285 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT);
286
287 current->journal_info = ti->ti_save;
288
289 if (ti->ti_flags & NILFS_TI_SYNC)
290 err = nilfs_construct_segment(sb);
291 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
292 kmem_cache_free(nilfs_transaction_cachep, ti);
293 sb_end_intwrite(sb);
294 return err;
295 }
296
nilfs_transaction_abort(struct super_block * sb)297 void nilfs_transaction_abort(struct super_block *sb)
298 {
299 struct nilfs_transaction_info *ti = current->journal_info;
300 struct the_nilfs *nilfs = sb->s_fs_info;
301
302 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
303 if (ti->ti_count > 0) {
304 ti->ti_count--;
305 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
306 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
307 return;
308 }
309 up_read(&nilfs->ns_segctor_sem);
310
311 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
312 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT);
313
314 current->journal_info = ti->ti_save;
315 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC)
316 kmem_cache_free(nilfs_transaction_cachep, ti);
317 sb_end_intwrite(sb);
318 }
319
nilfs_relax_pressure_in_lock(struct super_block * sb)320 void nilfs_relax_pressure_in_lock(struct super_block *sb)
321 {
322 struct the_nilfs *nilfs = sb->s_fs_info;
323 struct nilfs_sc_info *sci = nilfs->ns_writer;
324
325 if (sb_rdonly(sb) || unlikely(!sci) || !sci->sc_flush_request)
326 return;
327
328 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
329 up_read(&nilfs->ns_segctor_sem);
330
331 down_write(&nilfs->ns_segctor_sem);
332 if (sci->sc_flush_request &&
333 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) {
334 struct nilfs_transaction_info *ti = current->journal_info;
335
336 ti->ti_flags |= NILFS_TI_WRITER;
337 nilfs_segctor_do_immediate_flush(sci);
338 ti->ti_flags &= ~NILFS_TI_WRITER;
339 }
340 downgrade_write(&nilfs->ns_segctor_sem);
341 }
342
nilfs_transaction_lock(struct super_block * sb,struct nilfs_transaction_info * ti,int gcflag)343 static void nilfs_transaction_lock(struct super_block *sb,
344 struct nilfs_transaction_info *ti,
345 int gcflag)
346 {
347 struct nilfs_transaction_info *cur_ti = current->journal_info;
348 struct the_nilfs *nilfs = sb->s_fs_info;
349 struct nilfs_sc_info *sci = nilfs->ns_writer;
350
351 WARN_ON(cur_ti);
352 ti->ti_flags = NILFS_TI_WRITER;
353 ti->ti_count = 0;
354 ti->ti_save = cur_ti;
355 ti->ti_magic = NILFS_TI_MAGIC;
356 current->journal_info = ti;
357
358 for (;;) {
359 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
360 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK);
361
362 down_write(&nilfs->ns_segctor_sem);
363 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags))
364 break;
365
366 nilfs_segctor_do_immediate_flush(sci);
367
368 up_write(&nilfs->ns_segctor_sem);
369 cond_resched();
370 }
371 if (gcflag)
372 ti->ti_flags |= NILFS_TI_GC;
373
374 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
375 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK);
376 }
377
nilfs_transaction_unlock(struct super_block * sb)378 static void nilfs_transaction_unlock(struct super_block *sb)
379 {
380 struct nilfs_transaction_info *ti = current->journal_info;
381 struct the_nilfs *nilfs = sb->s_fs_info;
382
383 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC);
384 BUG_ON(ti->ti_count > 0);
385
386 up_write(&nilfs->ns_segctor_sem);
387 current->journal_info = ti->ti_save;
388
389 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count,
390 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK);
391 }
392
nilfs_segctor_map_segsum_entry(struct nilfs_sc_info * sci,struct nilfs_segsum_pointer * ssp,unsigned int bytes)393 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci,
394 struct nilfs_segsum_pointer *ssp,
395 unsigned int bytes)
396 {
397 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
398 unsigned int blocksize = sci->sc_super->s_blocksize;
399 void *p;
400
401 if (unlikely(ssp->offset + bytes > blocksize)) {
402 ssp->offset = 0;
403 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh,
404 &segbuf->sb_segsum_buffers));
405 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh);
406 }
407 p = ssp->bh->b_data + ssp->offset;
408 ssp->offset += bytes;
409 return p;
410 }
411
412 /**
413 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer
414 * @sci: nilfs_sc_info
415 */
nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info * sci)416 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci)
417 {
418 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
419 struct buffer_head *sumbh;
420 unsigned int sumbytes;
421 unsigned int flags = 0;
422 int err;
423
424 if (nilfs_doing_gc())
425 flags = NILFS_SS_GC;
426 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno);
427 if (unlikely(err))
428 return err;
429
430 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
431 sumbytes = segbuf->sb_sum.sumbytes;
432 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes;
433 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes;
434 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
435 return 0;
436 }
437
438 /**
439 * nilfs_segctor_zeropad_segsum - zero pad the rest of the segment summary area
440 * @sci: segment constructor object
441 *
442 * nilfs_segctor_zeropad_segsum() zero-fills unallocated space at the end of
443 * the current segment summary block.
444 */
nilfs_segctor_zeropad_segsum(struct nilfs_sc_info * sci)445 static void nilfs_segctor_zeropad_segsum(struct nilfs_sc_info *sci)
446 {
447 struct nilfs_segsum_pointer *ssp;
448
449 ssp = sci->sc_blk_cnt > 0 ? &sci->sc_binfo_ptr : &sci->sc_finfo_ptr;
450 if (ssp->offset < ssp->bh->b_size)
451 memset(ssp->bh->b_data + ssp->offset, 0,
452 ssp->bh->b_size - ssp->offset);
453 }
454
nilfs_segctor_feed_segment(struct nilfs_sc_info * sci)455 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci)
456 {
457 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
458 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs))
459 return -E2BIG; /*
460 * The current segment is filled up
461 * (internal code)
462 */
463 nilfs_segctor_zeropad_segsum(sci);
464 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg);
465 return nilfs_segctor_reset_segment_buffer(sci);
466 }
467
nilfs_segctor_add_super_root(struct nilfs_sc_info * sci)468 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci)
469 {
470 struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
471 int err;
472
473 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) {
474 err = nilfs_segctor_feed_segment(sci);
475 if (err)
476 return err;
477 segbuf = sci->sc_curseg;
478 }
479 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root);
480 if (likely(!err))
481 segbuf->sb_sum.flags |= NILFS_SS_SR;
482 return err;
483 }
484
485 /*
486 * Functions for making segment summary and payloads
487 */
nilfs_segctor_segsum_block_required(struct nilfs_sc_info * sci,const struct nilfs_segsum_pointer * ssp,unsigned int binfo_size)488 static int nilfs_segctor_segsum_block_required(
489 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp,
490 unsigned int binfo_size)
491 {
492 unsigned int blocksize = sci->sc_super->s_blocksize;
493 /* Size of finfo and binfo is enough small against blocksize */
494
495 return ssp->offset + binfo_size +
496 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) >
497 blocksize;
498 }
499
nilfs_segctor_begin_finfo(struct nilfs_sc_info * sci,struct inode * inode)500 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci,
501 struct inode *inode)
502 {
503 sci->sc_curseg->sb_sum.nfinfo++;
504 sci->sc_binfo_ptr = sci->sc_finfo_ptr;
505 nilfs_segctor_map_segsum_entry(
506 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo));
507
508 if (NILFS_I(inode)->i_root &&
509 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
510 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
511 /* skip finfo */
512 }
513
nilfs_segctor_end_finfo(struct nilfs_sc_info * sci,struct inode * inode)514 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci,
515 struct inode *inode)
516 {
517 struct nilfs_finfo *finfo;
518 struct nilfs_inode_info *ii;
519 struct nilfs_segment_buffer *segbuf;
520 __u64 cno;
521
522 if (sci->sc_blk_cnt == 0)
523 return;
524
525 ii = NILFS_I(inode);
526
527 if (test_bit(NILFS_I_GCINODE, &ii->i_state))
528 cno = ii->i_cno;
529 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino))
530 cno = 0;
531 else
532 cno = sci->sc_cno;
533
534 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr,
535 sizeof(*finfo));
536 finfo->fi_ino = cpu_to_le64(inode->i_ino);
537 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt);
538 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt);
539 finfo->fi_cno = cpu_to_le64(cno);
540
541 segbuf = sci->sc_curseg;
542 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset +
543 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1);
544 sci->sc_finfo_ptr = sci->sc_binfo_ptr;
545 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0;
546 }
547
nilfs_segctor_add_file_block(struct nilfs_sc_info * sci,struct buffer_head * bh,struct inode * inode,unsigned int binfo_size)548 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci,
549 struct buffer_head *bh,
550 struct inode *inode,
551 unsigned int binfo_size)
552 {
553 struct nilfs_segment_buffer *segbuf;
554 int required, err = 0;
555
556 retry:
557 segbuf = sci->sc_curseg;
558 required = nilfs_segctor_segsum_block_required(
559 sci, &sci->sc_binfo_ptr, binfo_size);
560 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) {
561 nilfs_segctor_end_finfo(sci, inode);
562 err = nilfs_segctor_feed_segment(sci);
563 if (err)
564 return err;
565 goto retry;
566 }
567 if (unlikely(required)) {
568 nilfs_segctor_zeropad_segsum(sci);
569 err = nilfs_segbuf_extend_segsum(segbuf);
570 if (unlikely(err))
571 goto failed;
572 }
573 if (sci->sc_blk_cnt == 0)
574 nilfs_segctor_begin_finfo(sci, inode);
575
576 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size);
577 /* Substitution to vblocknr is delayed until update_blocknr() */
578 nilfs_segbuf_add_file_buffer(segbuf, bh);
579 sci->sc_blk_cnt++;
580 failed:
581 return err;
582 }
583
584 /*
585 * Callback functions that enumerate, mark, and collect dirty blocks
586 */
nilfs_collect_file_data(struct nilfs_sc_info * sci,struct buffer_head * bh,struct inode * inode)587 static int nilfs_collect_file_data(struct nilfs_sc_info *sci,
588 struct buffer_head *bh, struct inode *inode)
589 {
590 int err;
591
592 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
593 if (err < 0)
594 return err;
595
596 err = nilfs_segctor_add_file_block(sci, bh, inode,
597 sizeof(struct nilfs_binfo_v));
598 if (!err)
599 sci->sc_datablk_cnt++;
600 return err;
601 }
602
nilfs_collect_file_node(struct nilfs_sc_info * sci,struct buffer_head * bh,struct inode * inode)603 static int nilfs_collect_file_node(struct nilfs_sc_info *sci,
604 struct buffer_head *bh,
605 struct inode *inode)
606 {
607 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
608 }
609
nilfs_collect_file_bmap(struct nilfs_sc_info * sci,struct buffer_head * bh,struct inode * inode)610 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci,
611 struct buffer_head *bh,
612 struct inode *inode)
613 {
614 WARN_ON(!buffer_dirty(bh));
615 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
616 }
617
nilfs_write_file_data_binfo(struct nilfs_sc_info * sci,struct nilfs_segsum_pointer * ssp,union nilfs_binfo * binfo)618 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci,
619 struct nilfs_segsum_pointer *ssp,
620 union nilfs_binfo *binfo)
621 {
622 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry(
623 sci, ssp, sizeof(*binfo_v));
624 *binfo_v = binfo->bi_v;
625 }
626
nilfs_write_file_node_binfo(struct nilfs_sc_info * sci,struct nilfs_segsum_pointer * ssp,union nilfs_binfo * binfo)627 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci,
628 struct nilfs_segsum_pointer *ssp,
629 union nilfs_binfo *binfo)
630 {
631 __le64 *vblocknr = nilfs_segctor_map_segsum_entry(
632 sci, ssp, sizeof(*vblocknr));
633 *vblocknr = binfo->bi_v.bi_vblocknr;
634 }
635
636 static const struct nilfs_sc_operations nilfs_sc_file_ops = {
637 .collect_data = nilfs_collect_file_data,
638 .collect_node = nilfs_collect_file_node,
639 .collect_bmap = nilfs_collect_file_bmap,
640 .write_data_binfo = nilfs_write_file_data_binfo,
641 .write_node_binfo = nilfs_write_file_node_binfo,
642 };
643
nilfs_collect_dat_data(struct nilfs_sc_info * sci,struct buffer_head * bh,struct inode * inode)644 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci,
645 struct buffer_head *bh, struct inode *inode)
646 {
647 int err;
648
649 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh);
650 if (err < 0)
651 return err;
652
653 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64));
654 if (!err)
655 sci->sc_datablk_cnt++;
656 return err;
657 }
658
nilfs_collect_dat_bmap(struct nilfs_sc_info * sci,struct buffer_head * bh,struct inode * inode)659 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci,
660 struct buffer_head *bh, struct inode *inode)
661 {
662 WARN_ON(!buffer_dirty(bh));
663 return nilfs_segctor_add_file_block(sci, bh, inode,
664 sizeof(struct nilfs_binfo_dat));
665 }
666
nilfs_write_dat_data_binfo(struct nilfs_sc_info * sci,struct nilfs_segsum_pointer * ssp,union nilfs_binfo * binfo)667 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci,
668 struct nilfs_segsum_pointer *ssp,
669 union nilfs_binfo *binfo)
670 {
671 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp,
672 sizeof(*blkoff));
673 *blkoff = binfo->bi_dat.bi_blkoff;
674 }
675
nilfs_write_dat_node_binfo(struct nilfs_sc_info * sci,struct nilfs_segsum_pointer * ssp,union nilfs_binfo * binfo)676 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci,
677 struct nilfs_segsum_pointer *ssp,
678 union nilfs_binfo *binfo)
679 {
680 struct nilfs_binfo_dat *binfo_dat =
681 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat));
682 *binfo_dat = binfo->bi_dat;
683 }
684
685 static const struct nilfs_sc_operations nilfs_sc_dat_ops = {
686 .collect_data = nilfs_collect_dat_data,
687 .collect_node = nilfs_collect_file_node,
688 .collect_bmap = nilfs_collect_dat_bmap,
689 .write_data_binfo = nilfs_write_dat_data_binfo,
690 .write_node_binfo = nilfs_write_dat_node_binfo,
691 };
692
693 static const struct nilfs_sc_operations nilfs_sc_dsync_ops = {
694 .collect_data = nilfs_collect_file_data,
695 .collect_node = NULL,
696 .collect_bmap = NULL,
697 .write_data_binfo = nilfs_write_file_data_binfo,
698 .write_node_binfo = NULL,
699 };
700
nilfs_lookup_dirty_data_buffers(struct inode * inode,struct list_head * listp,size_t nlimit,loff_t start,loff_t end)701 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
702 struct list_head *listp,
703 size_t nlimit,
704 loff_t start, loff_t end)
705 {
706 struct address_space *mapping = inode->i_mapping;
707 struct pagevec pvec;
708 pgoff_t index = 0, last = ULONG_MAX;
709 size_t ndirties = 0;
710 int i;
711
712 if (unlikely(start != 0 || end != LLONG_MAX)) {
713 /*
714 * A valid range is given for sync-ing data pages. The
715 * range is rounded to per-page; extra dirty buffers
716 * may be included if blocksize < pagesize.
717 */
718 index = start >> PAGE_SHIFT;
719 last = end >> PAGE_SHIFT;
720 }
721 pagevec_init(&pvec);
722 repeat:
723 if (unlikely(index > last) ||
724 !pagevec_lookup_range_tag(&pvec, mapping, &index, last,
725 PAGECACHE_TAG_DIRTY))
726 return ndirties;
727
728 for (i = 0; i < pagevec_count(&pvec); i++) {
729 struct buffer_head *bh, *head;
730 struct page *page = pvec.pages[i];
731
732 lock_page(page);
733 if (unlikely(page->mapping != mapping)) {
734 /* Exclude pages removed from the address space */
735 unlock_page(page);
736 continue;
737 }
738 if (!page_has_buffers(page))
739 create_empty_buffers(page, i_blocksize(inode), 0);
740 unlock_page(page);
741
742 bh = head = page_buffers(page);
743 do {
744 if (!buffer_dirty(bh) || buffer_async_write(bh))
745 continue;
746 get_bh(bh);
747 list_add_tail(&bh->b_assoc_buffers, listp);
748 ndirties++;
749 if (unlikely(ndirties >= nlimit)) {
750 pagevec_release(&pvec);
751 cond_resched();
752 return ndirties;
753 }
754 } while (bh = bh->b_this_page, bh != head);
755 }
756 pagevec_release(&pvec);
757 cond_resched();
758 goto repeat;
759 }
760
nilfs_lookup_dirty_node_buffers(struct inode * inode,struct list_head * listp)761 static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
762 struct list_head *listp)
763 {
764 struct nilfs_inode_info *ii = NILFS_I(inode);
765 struct inode *btnc_inode = ii->i_assoc_inode;
766 struct pagevec pvec;
767 struct buffer_head *bh, *head;
768 unsigned int i;
769 pgoff_t index = 0;
770
771 if (!btnc_inode)
772 return;
773
774 pagevec_init(&pvec);
775
776 while (pagevec_lookup_tag(&pvec, btnc_inode->i_mapping, &index,
777 PAGECACHE_TAG_DIRTY)) {
778 for (i = 0; i < pagevec_count(&pvec); i++) {
779 bh = head = page_buffers(pvec.pages[i]);
780 do {
781 if (buffer_dirty(bh) &&
782 !buffer_async_write(bh)) {
783 get_bh(bh);
784 list_add_tail(&bh->b_assoc_buffers,
785 listp);
786 }
787 bh = bh->b_this_page;
788 } while (bh != head);
789 }
790 pagevec_release(&pvec);
791 cond_resched();
792 }
793 }
794
nilfs_dispose_list(struct the_nilfs * nilfs,struct list_head * head,int force)795 static void nilfs_dispose_list(struct the_nilfs *nilfs,
796 struct list_head *head, int force)
797 {
798 struct nilfs_inode_info *ii, *n;
799 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii;
800 unsigned int nv = 0;
801
802 while (!list_empty(head)) {
803 spin_lock(&nilfs->ns_inode_lock);
804 list_for_each_entry_safe(ii, n, head, i_dirty) {
805 list_del_init(&ii->i_dirty);
806 if (force) {
807 if (unlikely(ii->i_bh)) {
808 brelse(ii->i_bh);
809 ii->i_bh = NULL;
810 }
811 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) {
812 set_bit(NILFS_I_QUEUED, &ii->i_state);
813 list_add_tail(&ii->i_dirty,
814 &nilfs->ns_dirty_files);
815 continue;
816 }
817 ivec[nv++] = ii;
818 if (nv == SC_N_INODEVEC)
819 break;
820 }
821 spin_unlock(&nilfs->ns_inode_lock);
822
823 for (pii = ivec; nv > 0; pii++, nv--)
824 iput(&(*pii)->vfs_inode);
825 }
826 }
827
nilfs_iput_work_func(struct work_struct * work)828 static void nilfs_iput_work_func(struct work_struct *work)
829 {
830 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info,
831 sc_iput_work);
832 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
833
834 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0);
835 }
836
nilfs_test_metadata_dirty(struct the_nilfs * nilfs,struct nilfs_root * root)837 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs,
838 struct nilfs_root *root)
839 {
840 int ret = 0;
841
842 if (nilfs_mdt_fetch_dirty(root->ifile))
843 ret++;
844 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile))
845 ret++;
846 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile))
847 ret++;
848 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat))
849 ret++;
850 return ret;
851 }
852
nilfs_segctor_clean(struct nilfs_sc_info * sci)853 static int nilfs_segctor_clean(struct nilfs_sc_info *sci)
854 {
855 return list_empty(&sci->sc_dirty_files) &&
856 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) &&
857 sci->sc_nfreesegs == 0 &&
858 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes));
859 }
860
nilfs_segctor_confirm(struct nilfs_sc_info * sci)861 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci)
862 {
863 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
864 int ret = 0;
865
866 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
867 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
868
869 spin_lock(&nilfs->ns_inode_lock);
870 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci))
871 ret++;
872
873 spin_unlock(&nilfs->ns_inode_lock);
874 return ret;
875 }
876
nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info * sci)877 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci)
878 {
879 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
880
881 nilfs_mdt_clear_dirty(sci->sc_root->ifile);
882 nilfs_mdt_clear_dirty(nilfs->ns_cpfile);
883 nilfs_mdt_clear_dirty(nilfs->ns_sufile);
884 nilfs_mdt_clear_dirty(nilfs->ns_dat);
885 }
886
nilfs_segctor_create_checkpoint(struct nilfs_sc_info * sci)887 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci)
888 {
889 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
890 struct buffer_head *bh_cp;
891 struct nilfs_checkpoint *raw_cp;
892 int err;
893
894 /* XXX: this interface will be changed */
895 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1,
896 &raw_cp, &bh_cp);
897 if (likely(!err)) {
898 /*
899 * The following code is duplicated with cpfile. But, it is
900 * needed to collect the checkpoint even if it was not newly
901 * created.
902 */
903 mark_buffer_dirty(bh_cp);
904 nilfs_mdt_mark_dirty(nilfs->ns_cpfile);
905 nilfs_cpfile_put_checkpoint(
906 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
907 } else if (err == -EINVAL || err == -ENOENT) {
908 nilfs_error(sci->sc_super,
909 "checkpoint creation failed due to metadata corruption.");
910 err = -EIO;
911 }
912 return err;
913 }
914
nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info * sci)915 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci)
916 {
917 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
918 struct buffer_head *bh_cp;
919 struct nilfs_checkpoint *raw_cp;
920 int err;
921
922 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0,
923 &raw_cp, &bh_cp);
924 if (unlikely(err)) {
925 if (err == -EINVAL || err == -ENOENT) {
926 nilfs_error(sci->sc_super,
927 "checkpoint finalization failed due to metadata corruption.");
928 err = -EIO;
929 }
930 goto failed_ibh;
931 }
932 raw_cp->cp_snapshot_list.ssl_next = 0;
933 raw_cp->cp_snapshot_list.ssl_prev = 0;
934 raw_cp->cp_inodes_count =
935 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count));
936 raw_cp->cp_blocks_count =
937 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count));
938 raw_cp->cp_nblk_inc =
939 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
940 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);
941 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno);
942
943 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags))
944 nilfs_checkpoint_clear_minor(raw_cp);
945 else
946 nilfs_checkpoint_set_minor(raw_cp);
947
948 nilfs_write_inode_common(sci->sc_root->ifile,
949 &raw_cp->cp_ifile_inode, 1);
950 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp);
951 return 0;
952
953 failed_ibh:
954 return err;
955 }
956
nilfs_fill_in_file_bmap(struct inode * ifile,struct nilfs_inode_info * ii)957 static void nilfs_fill_in_file_bmap(struct inode *ifile,
958 struct nilfs_inode_info *ii)
959
960 {
961 struct buffer_head *ibh;
962 struct nilfs_inode *raw_inode;
963
964 if (test_bit(NILFS_I_BMAP, &ii->i_state)) {
965 ibh = ii->i_bh;
966 BUG_ON(!ibh);
967 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino,
968 ibh);
969 nilfs_bmap_write(ii->i_bmap, raw_inode);
970 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh);
971 }
972 }
973
nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info * sci)974 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci)
975 {
976 struct nilfs_inode_info *ii;
977
978 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) {
979 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii);
980 set_bit(NILFS_I_COLLECTED, &ii->i_state);
981 }
982 }
983
nilfs_segctor_fill_in_super_root(struct nilfs_sc_info * sci,struct the_nilfs * nilfs)984 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci,
985 struct the_nilfs *nilfs)
986 {
987 struct buffer_head *bh_sr;
988 struct nilfs_super_root *raw_sr;
989 unsigned int isz, srsz;
990
991 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root;
992
993 lock_buffer(bh_sr);
994 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
995 isz = nilfs->ns_inode_size;
996 srsz = NILFS_SR_BYTES(isz);
997
998 raw_sr->sr_sum = 0; /* Ensure initialization within this update */
999 raw_sr->sr_bytes = cpu_to_le16(srsz);
1000 raw_sr->sr_nongc_ctime
1001 = cpu_to_le64(nilfs_doing_gc() ?
1002 nilfs->ns_nongc_ctime : sci->sc_seg_ctime);
1003 raw_sr->sr_flags = 0;
1004
1005 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr +
1006 NILFS_SR_DAT_OFFSET(isz), 1);
1007 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr +
1008 NILFS_SR_CPFILE_OFFSET(isz), 1);
1009 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr +
1010 NILFS_SR_SUFILE_OFFSET(isz), 1);
1011 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz);
1012 set_buffer_uptodate(bh_sr);
1013 unlock_buffer(bh_sr);
1014 }
1015
nilfs_redirty_inodes(struct list_head * head)1016 static void nilfs_redirty_inodes(struct list_head *head)
1017 {
1018 struct nilfs_inode_info *ii;
1019
1020 list_for_each_entry(ii, head, i_dirty) {
1021 if (test_bit(NILFS_I_COLLECTED, &ii->i_state))
1022 clear_bit(NILFS_I_COLLECTED, &ii->i_state);
1023 }
1024 }
1025
nilfs_drop_collected_inodes(struct list_head * head)1026 static void nilfs_drop_collected_inodes(struct list_head *head)
1027 {
1028 struct nilfs_inode_info *ii;
1029
1030 list_for_each_entry(ii, head, i_dirty) {
1031 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state))
1032 continue;
1033
1034 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state);
1035 set_bit(NILFS_I_UPDATED, &ii->i_state);
1036 }
1037 }
1038
nilfs_segctor_apply_buffers(struct nilfs_sc_info * sci,struct inode * inode,struct list_head * listp,int (* collect)(struct nilfs_sc_info *,struct buffer_head *,struct inode *))1039 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci,
1040 struct inode *inode,
1041 struct list_head *listp,
1042 int (*collect)(struct nilfs_sc_info *,
1043 struct buffer_head *,
1044 struct inode *))
1045 {
1046 struct buffer_head *bh, *n;
1047 int err = 0;
1048
1049 if (collect) {
1050 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) {
1051 list_del_init(&bh->b_assoc_buffers);
1052 err = collect(sci, bh, inode);
1053 brelse(bh);
1054 if (unlikely(err))
1055 goto dispose_buffers;
1056 }
1057 return 0;
1058 }
1059
1060 dispose_buffers:
1061 while (!list_empty(listp)) {
1062 bh = list_first_entry(listp, struct buffer_head,
1063 b_assoc_buffers);
1064 list_del_init(&bh->b_assoc_buffers);
1065 brelse(bh);
1066 }
1067 return err;
1068 }
1069
nilfs_segctor_buffer_rest(struct nilfs_sc_info * sci)1070 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
1071 {
1072 /* Remaining number of blocks within segment buffer */
1073 return sci->sc_segbuf_nblocks -
1074 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
1075 }
1076
nilfs_segctor_scan_file(struct nilfs_sc_info * sci,struct inode * inode,const struct nilfs_sc_operations * sc_ops)1077 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
1078 struct inode *inode,
1079 const struct nilfs_sc_operations *sc_ops)
1080 {
1081 LIST_HEAD(data_buffers);
1082 LIST_HEAD(node_buffers);
1083 int err;
1084
1085 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1086 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1087
1088 n = nilfs_lookup_dirty_data_buffers(
1089 inode, &data_buffers, rest + 1, 0, LLONG_MAX);
1090 if (n > rest) {
1091 err = nilfs_segctor_apply_buffers(
1092 sci, inode, &data_buffers,
1093 sc_ops->collect_data);
1094 BUG_ON(!err); /* always receive -E2BIG or true error */
1095 goto break_or_fail;
1096 }
1097 }
1098 nilfs_lookup_dirty_node_buffers(inode, &node_buffers);
1099
1100 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
1101 err = nilfs_segctor_apply_buffers(
1102 sci, inode, &data_buffers, sc_ops->collect_data);
1103 if (unlikely(err)) {
1104 /* dispose node list */
1105 nilfs_segctor_apply_buffers(
1106 sci, inode, &node_buffers, NULL);
1107 goto break_or_fail;
1108 }
1109 sci->sc_stage.flags |= NILFS_CF_NODE;
1110 }
1111 /* Collect node */
1112 err = nilfs_segctor_apply_buffers(
1113 sci, inode, &node_buffers, sc_ops->collect_node);
1114 if (unlikely(err))
1115 goto break_or_fail;
1116
1117 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers);
1118 err = nilfs_segctor_apply_buffers(
1119 sci, inode, &node_buffers, sc_ops->collect_bmap);
1120 if (unlikely(err))
1121 goto break_or_fail;
1122
1123 nilfs_segctor_end_finfo(sci, inode);
1124 sci->sc_stage.flags &= ~NILFS_CF_NODE;
1125
1126 break_or_fail:
1127 return err;
1128 }
1129
nilfs_segctor_scan_file_dsync(struct nilfs_sc_info * sci,struct inode * inode)1130 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci,
1131 struct inode *inode)
1132 {
1133 LIST_HEAD(data_buffers);
1134 size_t n, rest = nilfs_segctor_buffer_rest(sci);
1135 int err;
1136
1137 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
1138 sci->sc_dsync_start,
1139 sci->sc_dsync_end);
1140
1141 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
1142 nilfs_collect_file_data);
1143 if (!err) {
1144 nilfs_segctor_end_finfo(sci, inode);
1145 BUG_ON(n > rest);
1146 /* always receive -E2BIG or true error if n > rest */
1147 }
1148 return err;
1149 }
1150
nilfs_segctor_collect_blocks(struct nilfs_sc_info * sci,int mode)1151 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode)
1152 {
1153 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1154 struct list_head *head;
1155 struct nilfs_inode_info *ii;
1156 size_t ndone;
1157 int err = 0;
1158
1159 switch (nilfs_sc_cstage_get(sci)) {
1160 case NILFS_ST_INIT:
1161 /* Pre-processes */
1162 sci->sc_stage.flags = 0;
1163
1164 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) {
1165 sci->sc_nblk_inc = 0;
1166 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN;
1167 if (mode == SC_LSEG_DSYNC) {
1168 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC);
1169 goto dsync_mode;
1170 }
1171 }
1172
1173 sci->sc_stage.dirty_file_ptr = NULL;
1174 sci->sc_stage.gc_inode_ptr = NULL;
1175 if (mode == SC_FLUSH_DAT) {
1176 nilfs_sc_cstage_set(sci, NILFS_ST_DAT);
1177 goto dat_stage;
1178 }
1179 nilfs_sc_cstage_inc(sci);
1180 fallthrough;
1181 case NILFS_ST_GC:
1182 if (nilfs_doing_gc()) {
1183 head = &sci->sc_gc_inodes;
1184 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr,
1185 head, i_dirty);
1186 list_for_each_entry_continue(ii, head, i_dirty) {
1187 err = nilfs_segctor_scan_file(
1188 sci, &ii->vfs_inode,
1189 &nilfs_sc_file_ops);
1190 if (unlikely(err)) {
1191 sci->sc_stage.gc_inode_ptr = list_entry(
1192 ii->i_dirty.prev,
1193 struct nilfs_inode_info,
1194 i_dirty);
1195 goto break_or_fail;
1196 }
1197 set_bit(NILFS_I_COLLECTED, &ii->i_state);
1198 }
1199 sci->sc_stage.gc_inode_ptr = NULL;
1200 }
1201 nilfs_sc_cstage_inc(sci);
1202 fallthrough;
1203 case NILFS_ST_FILE:
1204 head = &sci->sc_dirty_files;
1205 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head,
1206 i_dirty);
1207 list_for_each_entry_continue(ii, head, i_dirty) {
1208 clear_bit(NILFS_I_DIRTY, &ii->i_state);
1209
1210 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode,
1211 &nilfs_sc_file_ops);
1212 if (unlikely(err)) {
1213 sci->sc_stage.dirty_file_ptr =
1214 list_entry(ii->i_dirty.prev,
1215 struct nilfs_inode_info,
1216 i_dirty);
1217 goto break_or_fail;
1218 }
1219 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */
1220 /* XXX: required ? */
1221 }
1222 sci->sc_stage.dirty_file_ptr = NULL;
1223 if (mode == SC_FLUSH_FILE) {
1224 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1225 return 0;
1226 }
1227 nilfs_sc_cstage_inc(sci);
1228 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED;
1229 fallthrough;
1230 case NILFS_ST_IFILE:
1231 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile,
1232 &nilfs_sc_file_ops);
1233 if (unlikely(err))
1234 break;
1235 nilfs_sc_cstage_inc(sci);
1236 /* Creating a checkpoint */
1237 err = nilfs_segctor_create_checkpoint(sci);
1238 if (unlikely(err))
1239 break;
1240 fallthrough;
1241 case NILFS_ST_CPFILE:
1242 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile,
1243 &nilfs_sc_file_ops);
1244 if (unlikely(err))
1245 break;
1246 nilfs_sc_cstage_inc(sci);
1247 fallthrough;
1248 case NILFS_ST_SUFILE:
1249 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs,
1250 sci->sc_nfreesegs, &ndone);
1251 if (unlikely(err)) {
1252 nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1253 sci->sc_freesegs, ndone,
1254 NULL);
1255 break;
1256 }
1257 sci->sc_stage.flags |= NILFS_CF_SUFREED;
1258
1259 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile,
1260 &nilfs_sc_file_ops);
1261 if (unlikely(err))
1262 break;
1263 nilfs_sc_cstage_inc(sci);
1264 fallthrough;
1265 case NILFS_ST_DAT:
1266 dat_stage:
1267 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat,
1268 &nilfs_sc_dat_ops);
1269 if (unlikely(err))
1270 break;
1271 if (mode == SC_FLUSH_DAT) {
1272 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1273 return 0;
1274 }
1275 nilfs_sc_cstage_inc(sci);
1276 fallthrough;
1277 case NILFS_ST_SR:
1278 if (mode == SC_LSEG_SR) {
1279 /* Appending a super root */
1280 err = nilfs_segctor_add_super_root(sci);
1281 if (unlikely(err))
1282 break;
1283 }
1284 /* End of a logical segment */
1285 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1286 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1287 return 0;
1288 case NILFS_ST_DSYNC:
1289 dsync_mode:
1290 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
1291 ii = sci->sc_dsync_inode;
1292 if (!test_bit(NILFS_I_BUSY, &ii->i_state))
1293 break;
1294
1295 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
1296 if (unlikely(err))
1297 break;
1298 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
1299 nilfs_sc_cstage_set(sci, NILFS_ST_DONE);
1300 return 0;
1301 case NILFS_ST_DONE:
1302 return 0;
1303 default:
1304 BUG();
1305 }
1306
1307 break_or_fail:
1308 return err;
1309 }
1310
1311 /**
1312 * nilfs_segctor_begin_construction - setup segment buffer to make a new log
1313 * @sci: nilfs_sc_info
1314 * @nilfs: nilfs object
1315 */
nilfs_segctor_begin_construction(struct nilfs_sc_info * sci,struct the_nilfs * nilfs)1316 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci,
1317 struct the_nilfs *nilfs)
1318 {
1319 struct nilfs_segment_buffer *segbuf, *prev;
1320 __u64 nextnum;
1321 int err, alloc = 0;
1322
1323 segbuf = nilfs_segbuf_new(sci->sc_super);
1324 if (unlikely(!segbuf))
1325 return -ENOMEM;
1326
1327 if (list_empty(&sci->sc_write_logs)) {
1328 nilfs_segbuf_map(segbuf, nilfs->ns_segnum,
1329 nilfs->ns_pseg_offset, nilfs);
1330 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1331 nilfs_shift_to_next_segment(nilfs);
1332 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs);
1333 }
1334
1335 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq;
1336 nextnum = nilfs->ns_nextnum;
1337
1338 if (nilfs->ns_segnum == nilfs->ns_nextnum)
1339 /* Start from the head of a new full segment */
1340 alloc++;
1341 } else {
1342 /* Continue logs */
1343 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1344 nilfs_segbuf_map_cont(segbuf, prev);
1345 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq;
1346 nextnum = prev->sb_nextnum;
1347
1348 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) {
1349 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1350 segbuf->sb_sum.seg_seq++;
1351 alloc++;
1352 }
1353 }
1354
1355 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum);
1356 if (err)
1357 goto failed;
1358
1359 if (alloc) {
1360 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum);
1361 if (err)
1362 goto failed;
1363 }
1364 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs);
1365
1366 BUG_ON(!list_empty(&sci->sc_segbufs));
1367 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs);
1368 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks;
1369 return 0;
1370
1371 failed:
1372 nilfs_segbuf_free(segbuf);
1373 return err;
1374 }
1375
nilfs_segctor_extend_segments(struct nilfs_sc_info * sci,struct the_nilfs * nilfs,int nadd)1376 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
1377 struct the_nilfs *nilfs, int nadd)
1378 {
1379 struct nilfs_segment_buffer *segbuf, *prev;
1380 struct inode *sufile = nilfs->ns_sufile;
1381 __u64 nextnextnum;
1382 LIST_HEAD(list);
1383 int err, ret, i;
1384
1385 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs);
1386 /*
1387 * Since the segment specified with nextnum might be allocated during
1388 * the previous construction, the buffer including its segusage may
1389 * not be dirty. The following call ensures that the buffer is dirty
1390 * and will pin the buffer on memory until the sufile is written.
1391 */
1392 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum);
1393 if (unlikely(err))
1394 return err;
1395
1396 for (i = 0; i < nadd; i++) {
1397 /* extend segment info */
1398 err = -ENOMEM;
1399 segbuf = nilfs_segbuf_new(sci->sc_super);
1400 if (unlikely(!segbuf))
1401 goto failed;
1402
1403 /* map this buffer to region of segment on-disk */
1404 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs);
1405 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks;
1406
1407 /* allocate the next next full segment */
1408 err = nilfs_sufile_alloc(sufile, &nextnextnum);
1409 if (unlikely(err))
1410 goto failed_segbuf;
1411
1412 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1;
1413 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs);
1414
1415 list_add_tail(&segbuf->sb_list, &list);
1416 prev = segbuf;
1417 }
1418 list_splice_tail(&list, &sci->sc_segbufs);
1419 return 0;
1420
1421 failed_segbuf:
1422 nilfs_segbuf_free(segbuf);
1423 failed:
1424 list_for_each_entry(segbuf, &list, sb_list) {
1425 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1426 WARN_ON(ret); /* never fails */
1427 }
1428 nilfs_destroy_logs(&list);
1429 return err;
1430 }
1431
nilfs_free_incomplete_logs(struct list_head * logs,struct the_nilfs * nilfs)1432 static void nilfs_free_incomplete_logs(struct list_head *logs,
1433 struct the_nilfs *nilfs)
1434 {
1435 struct nilfs_segment_buffer *segbuf, *prev;
1436 struct inode *sufile = nilfs->ns_sufile;
1437 int ret;
1438
1439 segbuf = NILFS_FIRST_SEGBUF(logs);
1440 if (nilfs->ns_nextnum != segbuf->sb_nextnum) {
1441 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1442 WARN_ON(ret); /* never fails */
1443 }
1444 if (atomic_read(&segbuf->sb_err)) {
1445 /* Case 1: The first segment failed */
1446 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start)
1447 /*
1448 * Case 1a: Partial segment appended into an existing
1449 * segment
1450 */
1451 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start,
1452 segbuf->sb_fseg_end);
1453 else /* Case 1b: New full segment */
1454 set_nilfs_discontinued(nilfs);
1455 }
1456
1457 prev = segbuf;
1458 list_for_each_entry_continue(segbuf, logs, sb_list) {
1459 if (prev->sb_nextnum != segbuf->sb_nextnum) {
1460 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1461 WARN_ON(ret); /* never fails */
1462 }
1463 if (atomic_read(&segbuf->sb_err) &&
1464 segbuf->sb_segnum != nilfs->ns_nextnum)
1465 /* Case 2: extended segment (!= next) failed */
1466 nilfs_sufile_set_error(sufile, segbuf->sb_segnum);
1467 prev = segbuf;
1468 }
1469 }
1470
nilfs_segctor_update_segusage(struct nilfs_sc_info * sci,struct inode * sufile)1471 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci,
1472 struct inode *sufile)
1473 {
1474 struct nilfs_segment_buffer *segbuf;
1475 unsigned long live_blocks;
1476 int ret;
1477
1478 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1479 live_blocks = segbuf->sb_sum.nblocks +
1480 (segbuf->sb_pseg_start - segbuf->sb_fseg_start);
1481 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1482 live_blocks,
1483 sci->sc_seg_ctime);
1484 WARN_ON(ret); /* always succeed because the segusage is dirty */
1485 }
1486 }
1487
nilfs_cancel_segusage(struct list_head * logs,struct inode * sufile)1488 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile)
1489 {
1490 struct nilfs_segment_buffer *segbuf;
1491 int ret;
1492
1493 segbuf = NILFS_FIRST_SEGBUF(logs);
1494 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1495 segbuf->sb_pseg_start -
1496 segbuf->sb_fseg_start, 0);
1497 WARN_ON(ret); /* always succeed because the segusage is dirty */
1498
1499 list_for_each_entry_continue(segbuf, logs, sb_list) {
1500 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum,
1501 0, 0);
1502 WARN_ON(ret); /* always succeed */
1503 }
1504 }
1505
nilfs_segctor_truncate_segments(struct nilfs_sc_info * sci,struct nilfs_segment_buffer * last,struct inode * sufile)1506 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci,
1507 struct nilfs_segment_buffer *last,
1508 struct inode *sufile)
1509 {
1510 struct nilfs_segment_buffer *segbuf = last;
1511 int ret;
1512
1513 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) {
1514 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks;
1515 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum);
1516 WARN_ON(ret);
1517 }
1518 nilfs_truncate_logs(&sci->sc_segbufs, last);
1519 }
1520
1521
nilfs_segctor_collect(struct nilfs_sc_info * sci,struct the_nilfs * nilfs,int mode)1522 static int nilfs_segctor_collect(struct nilfs_sc_info *sci,
1523 struct the_nilfs *nilfs, int mode)
1524 {
1525 struct nilfs_cstage prev_stage = sci->sc_stage;
1526 int err, nadd = 1;
1527
1528 /* Collection retry loop */
1529 for (;;) {
1530 sci->sc_nblk_this_inc = 0;
1531 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs);
1532
1533 err = nilfs_segctor_reset_segment_buffer(sci);
1534 if (unlikely(err))
1535 goto failed;
1536
1537 err = nilfs_segctor_collect_blocks(sci, mode);
1538 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks;
1539 if (!err)
1540 break;
1541
1542 if (unlikely(err != -E2BIG))
1543 goto failed;
1544
1545 /* The current segment is filled up */
1546 if (mode != SC_LSEG_SR ||
1547 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE)
1548 break;
1549
1550 nilfs_clear_logs(&sci->sc_segbufs);
1551
1552 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1553 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1554 sci->sc_freesegs,
1555 sci->sc_nfreesegs,
1556 NULL);
1557 WARN_ON(err); /* do not happen */
1558 sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
1559 }
1560
1561 err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
1562 if (unlikely(err))
1563 return err;
1564
1565 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
1566 sci->sc_stage = prev_stage;
1567 }
1568 nilfs_segctor_zeropad_segsum(sci);
1569 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile);
1570 return 0;
1571
1572 failed:
1573 return err;
1574 }
1575
nilfs_list_replace_buffer(struct buffer_head * old_bh,struct buffer_head * new_bh)1576 static void nilfs_list_replace_buffer(struct buffer_head *old_bh,
1577 struct buffer_head *new_bh)
1578 {
1579 BUG_ON(!list_empty(&new_bh->b_assoc_buffers));
1580
1581 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers);
1582 /* The caller must release old_bh */
1583 }
1584
1585 static int
nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info * sci,struct nilfs_segment_buffer * segbuf,int mode)1586 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci,
1587 struct nilfs_segment_buffer *segbuf,
1588 int mode)
1589 {
1590 struct inode *inode = NULL;
1591 sector_t blocknr;
1592 unsigned long nfinfo = segbuf->sb_sum.nfinfo;
1593 unsigned long nblocks = 0, ndatablk = 0;
1594 const struct nilfs_sc_operations *sc_op = NULL;
1595 struct nilfs_segsum_pointer ssp;
1596 struct nilfs_finfo *finfo = NULL;
1597 union nilfs_binfo binfo;
1598 struct buffer_head *bh, *bh_org;
1599 ino_t ino = 0;
1600 int err = 0;
1601
1602 if (!nfinfo)
1603 goto out;
1604
1605 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk;
1606 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers);
1607 ssp.offset = sizeof(struct nilfs_segment_summary);
1608
1609 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) {
1610 if (bh == segbuf->sb_super_root)
1611 break;
1612 if (!finfo) {
1613 finfo = nilfs_segctor_map_segsum_entry(
1614 sci, &ssp, sizeof(*finfo));
1615 ino = le64_to_cpu(finfo->fi_ino);
1616 nblocks = le32_to_cpu(finfo->fi_nblocks);
1617 ndatablk = le32_to_cpu(finfo->fi_ndatablk);
1618
1619 inode = bh->b_page->mapping->host;
1620
1621 if (mode == SC_LSEG_DSYNC)
1622 sc_op = &nilfs_sc_dsync_ops;
1623 else if (ino == NILFS_DAT_INO)
1624 sc_op = &nilfs_sc_dat_ops;
1625 else /* file blocks */
1626 sc_op = &nilfs_sc_file_ops;
1627 }
1628 bh_org = bh;
1629 get_bh(bh_org);
1630 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr,
1631 &binfo);
1632 if (bh != bh_org)
1633 nilfs_list_replace_buffer(bh_org, bh);
1634 brelse(bh_org);
1635 if (unlikely(err))
1636 goto failed_bmap;
1637
1638 if (ndatablk > 0)
1639 sc_op->write_data_binfo(sci, &ssp, &binfo);
1640 else
1641 sc_op->write_node_binfo(sci, &ssp, &binfo);
1642
1643 blocknr++;
1644 if (--nblocks == 0) {
1645 finfo = NULL;
1646 if (--nfinfo == 0)
1647 break;
1648 } else if (ndatablk > 0)
1649 ndatablk--;
1650 }
1651 out:
1652 return 0;
1653
1654 failed_bmap:
1655 return err;
1656 }
1657
nilfs_segctor_assign(struct nilfs_sc_info * sci,int mode)1658 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode)
1659 {
1660 struct nilfs_segment_buffer *segbuf;
1661 int err;
1662
1663 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1664 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode);
1665 if (unlikely(err))
1666 return err;
1667 nilfs_segbuf_fill_in_segsum(segbuf);
1668 }
1669 return 0;
1670 }
1671
nilfs_begin_page_io(struct page * page)1672 static void nilfs_begin_page_io(struct page *page)
1673 {
1674 if (!page || PageWriteback(page))
1675 /*
1676 * For split b-tree node pages, this function may be called
1677 * twice. We ignore the 2nd or later calls by this check.
1678 */
1679 return;
1680
1681 lock_page(page);
1682 clear_page_dirty_for_io(page);
1683 set_page_writeback(page);
1684 unlock_page(page);
1685 }
1686
nilfs_segctor_prepare_write(struct nilfs_sc_info * sci)1687 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci)
1688 {
1689 struct nilfs_segment_buffer *segbuf;
1690 struct page *bd_page = NULL, *fs_page = NULL;
1691
1692 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) {
1693 struct buffer_head *bh;
1694
1695 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1696 b_assoc_buffers) {
1697 if (bh->b_page != bd_page) {
1698 if (bd_page) {
1699 lock_page(bd_page);
1700 clear_page_dirty_for_io(bd_page);
1701 set_page_writeback(bd_page);
1702 unlock_page(bd_page);
1703 }
1704 bd_page = bh->b_page;
1705 }
1706 }
1707
1708 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1709 b_assoc_buffers) {
1710 if (bh == segbuf->sb_super_root) {
1711 if (bh->b_page != bd_page) {
1712 lock_page(bd_page);
1713 clear_page_dirty_for_io(bd_page);
1714 set_page_writeback(bd_page);
1715 unlock_page(bd_page);
1716 bd_page = bh->b_page;
1717 }
1718 break;
1719 }
1720 set_buffer_async_write(bh);
1721 if (bh->b_page != fs_page) {
1722 nilfs_begin_page_io(fs_page);
1723 fs_page = bh->b_page;
1724 }
1725 }
1726 }
1727 if (bd_page) {
1728 lock_page(bd_page);
1729 clear_page_dirty_for_io(bd_page);
1730 set_page_writeback(bd_page);
1731 unlock_page(bd_page);
1732 }
1733 nilfs_begin_page_io(fs_page);
1734 }
1735
nilfs_segctor_write(struct nilfs_sc_info * sci,struct the_nilfs * nilfs)1736 static int nilfs_segctor_write(struct nilfs_sc_info *sci,
1737 struct the_nilfs *nilfs)
1738 {
1739 int ret;
1740
1741 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs);
1742 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs);
1743 return ret;
1744 }
1745
nilfs_end_page_io(struct page * page,int err)1746 static void nilfs_end_page_io(struct page *page, int err)
1747 {
1748 if (!page)
1749 return;
1750
1751 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) {
1752 /*
1753 * For b-tree node pages, this function may be called twice
1754 * or more because they might be split in a segment.
1755 */
1756 if (PageDirty(page)) {
1757 /*
1758 * For pages holding split b-tree node buffers, dirty
1759 * flag on the buffers may be cleared discretely.
1760 * In that case, the page is once redirtied for
1761 * remaining buffers, and it must be cancelled if
1762 * all the buffers get cleaned later.
1763 */
1764 lock_page(page);
1765 if (nilfs_page_buffers_clean(page))
1766 __nilfs_clear_page_dirty(page);
1767 unlock_page(page);
1768 }
1769 return;
1770 }
1771
1772 if (!err) {
1773 if (!nilfs_page_buffers_clean(page))
1774 __set_page_dirty_nobuffers(page);
1775 ClearPageError(page);
1776 } else {
1777 __set_page_dirty_nobuffers(page);
1778 SetPageError(page);
1779 }
1780
1781 end_page_writeback(page);
1782 }
1783
nilfs_abort_logs(struct list_head * logs,int err)1784 static void nilfs_abort_logs(struct list_head *logs, int err)
1785 {
1786 struct nilfs_segment_buffer *segbuf;
1787 struct page *bd_page = NULL, *fs_page = NULL;
1788 struct buffer_head *bh;
1789
1790 if (list_empty(logs))
1791 return;
1792
1793 list_for_each_entry(segbuf, logs, sb_list) {
1794 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1795 b_assoc_buffers) {
1796 clear_buffer_uptodate(bh);
1797 if (bh->b_page != bd_page) {
1798 if (bd_page)
1799 end_page_writeback(bd_page);
1800 bd_page = bh->b_page;
1801 }
1802 }
1803
1804 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1805 b_assoc_buffers) {
1806 if (bh == segbuf->sb_super_root) {
1807 clear_buffer_uptodate(bh);
1808 if (bh->b_page != bd_page) {
1809 end_page_writeback(bd_page);
1810 bd_page = bh->b_page;
1811 }
1812 break;
1813 }
1814 clear_buffer_async_write(bh);
1815 if (bh->b_page != fs_page) {
1816 nilfs_end_page_io(fs_page, err);
1817 fs_page = bh->b_page;
1818 }
1819 }
1820 }
1821 if (bd_page)
1822 end_page_writeback(bd_page);
1823
1824 nilfs_end_page_io(fs_page, err);
1825 }
1826
nilfs_segctor_abort_construction(struct nilfs_sc_info * sci,struct the_nilfs * nilfs,int err)1827 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci,
1828 struct the_nilfs *nilfs, int err)
1829 {
1830 LIST_HEAD(logs);
1831 int ret;
1832
1833 list_splice_tail_init(&sci->sc_write_logs, &logs);
1834 ret = nilfs_wait_on_logs(&logs);
1835 nilfs_abort_logs(&logs, ret ? : err);
1836
1837 list_splice_tail_init(&sci->sc_segbufs, &logs);
1838 nilfs_cancel_segusage(&logs, nilfs->ns_sufile);
1839 nilfs_free_incomplete_logs(&logs, nilfs);
1840
1841 if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
1842 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
1843 sci->sc_freesegs,
1844 sci->sc_nfreesegs,
1845 NULL);
1846 WARN_ON(ret); /* do not happen */
1847 }
1848
1849 nilfs_destroy_logs(&logs);
1850 }
1851
nilfs_set_next_segment(struct the_nilfs * nilfs,struct nilfs_segment_buffer * segbuf)1852 static void nilfs_set_next_segment(struct the_nilfs *nilfs,
1853 struct nilfs_segment_buffer *segbuf)
1854 {
1855 nilfs->ns_segnum = segbuf->sb_segnum;
1856 nilfs->ns_nextnum = segbuf->sb_nextnum;
1857 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start
1858 + segbuf->sb_sum.nblocks;
1859 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq;
1860 nilfs->ns_ctime = segbuf->sb_sum.ctime;
1861 }
1862
nilfs_segctor_complete_write(struct nilfs_sc_info * sci)1863 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
1864 {
1865 struct nilfs_segment_buffer *segbuf;
1866 struct page *bd_page = NULL, *fs_page = NULL;
1867 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
1868 int update_sr = false;
1869
1870 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) {
1871 struct buffer_head *bh;
1872
1873 list_for_each_entry(bh, &segbuf->sb_segsum_buffers,
1874 b_assoc_buffers) {
1875 set_buffer_uptodate(bh);
1876 clear_buffer_dirty(bh);
1877 if (bh->b_page != bd_page) {
1878 if (bd_page)
1879 end_page_writeback(bd_page);
1880 bd_page = bh->b_page;
1881 }
1882 }
1883 /*
1884 * We assume that the buffers which belong to the same page
1885 * continue over the buffer list.
1886 * Under this assumption, the last BHs of pages is
1887 * identifiable by the discontinuity of bh->b_page
1888 * (page != fs_page).
1889 *
1890 * For B-tree node blocks, however, this assumption is not
1891 * guaranteed. The cleanup code of B-tree node pages needs
1892 * special care.
1893 */
1894 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
1895 b_assoc_buffers) {
1896 const unsigned long set_bits = BIT(BH_Uptodate);
1897 const unsigned long clear_bits =
1898 (BIT(BH_Dirty) | BIT(BH_Async_Write) |
1899 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) |
1900 BIT(BH_NILFS_Redirected));
1901
1902 if (bh == segbuf->sb_super_root) {
1903 set_buffer_uptodate(bh);
1904 clear_buffer_dirty(bh);
1905 if (bh->b_page != bd_page) {
1906 end_page_writeback(bd_page);
1907 bd_page = bh->b_page;
1908 }
1909 update_sr = true;
1910 break;
1911 }
1912 set_mask_bits(&bh->b_state, clear_bits, set_bits);
1913 if (bh->b_page != fs_page) {
1914 nilfs_end_page_io(fs_page, 0);
1915 fs_page = bh->b_page;
1916 }
1917 }
1918
1919 if (!nilfs_segbuf_simplex(segbuf)) {
1920 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) {
1921 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1922 sci->sc_lseg_stime = jiffies;
1923 }
1924 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND)
1925 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags);
1926 }
1927 }
1928 /*
1929 * Since pages may continue over multiple segment buffers,
1930 * end of the last page must be checked outside of the loop.
1931 */
1932 if (bd_page)
1933 end_page_writeback(bd_page);
1934
1935 nilfs_end_page_io(fs_page, 0);
1936
1937 nilfs_drop_collected_inodes(&sci->sc_dirty_files);
1938
1939 if (nilfs_doing_gc())
1940 nilfs_drop_collected_inodes(&sci->sc_gc_inodes);
1941 else
1942 nilfs->ns_nongc_ctime = sci->sc_seg_ctime;
1943
1944 sci->sc_nblk_inc += sci->sc_nblk_this_inc;
1945
1946 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs);
1947 nilfs_set_next_segment(nilfs, segbuf);
1948
1949 if (update_sr) {
1950 nilfs->ns_flushed_device = 0;
1951 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
1952 segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
1953
1954 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
1955 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
1956 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1957 nilfs_segctor_clear_metadata_dirty(sci);
1958 } else
1959 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags);
1960 }
1961
nilfs_segctor_wait(struct nilfs_sc_info * sci)1962 static int nilfs_segctor_wait(struct nilfs_sc_info *sci)
1963 {
1964 int ret;
1965
1966 ret = nilfs_wait_on_logs(&sci->sc_write_logs);
1967 if (!ret) {
1968 nilfs_segctor_complete_write(sci);
1969 nilfs_destroy_logs(&sci->sc_write_logs);
1970 }
1971 return ret;
1972 }
1973
nilfs_segctor_collect_dirty_files(struct nilfs_sc_info * sci,struct the_nilfs * nilfs)1974 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
1975 struct the_nilfs *nilfs)
1976 {
1977 struct nilfs_inode_info *ii, *n;
1978 struct inode *ifile = sci->sc_root->ifile;
1979
1980 spin_lock(&nilfs->ns_inode_lock);
1981 retry:
1982 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) {
1983 if (!ii->i_bh) {
1984 struct buffer_head *ibh;
1985 int err;
1986
1987 spin_unlock(&nilfs->ns_inode_lock);
1988 err = nilfs_ifile_get_inode_block(
1989 ifile, ii->vfs_inode.i_ino, &ibh);
1990 if (unlikely(err)) {
1991 nilfs_warn(sci->sc_super,
1992 "log writer: error %d getting inode block (ino=%lu)",
1993 err, ii->vfs_inode.i_ino);
1994 return err;
1995 }
1996 spin_lock(&nilfs->ns_inode_lock);
1997 if (likely(!ii->i_bh))
1998 ii->i_bh = ibh;
1999 else
2000 brelse(ibh);
2001 goto retry;
2002 }
2003
2004 // Always redirty the buffer to avoid race condition
2005 mark_buffer_dirty(ii->i_bh);
2006 nilfs_mdt_mark_dirty(ifile);
2007
2008 clear_bit(NILFS_I_QUEUED, &ii->i_state);
2009 set_bit(NILFS_I_BUSY, &ii->i_state);
2010 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
2011 }
2012 spin_unlock(&nilfs->ns_inode_lock);
2013
2014 return 0;
2015 }
2016
nilfs_segctor_drop_written_files(struct nilfs_sc_info * sci,struct the_nilfs * nilfs)2017 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci,
2018 struct the_nilfs *nilfs)
2019 {
2020 struct nilfs_inode_info *ii, *n;
2021 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE);
2022 int defer_iput = false;
2023
2024 spin_lock(&nilfs->ns_inode_lock);
2025 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) {
2026 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) ||
2027 test_bit(NILFS_I_DIRTY, &ii->i_state))
2028 continue;
2029
2030 clear_bit(NILFS_I_BUSY, &ii->i_state);
2031 brelse(ii->i_bh);
2032 ii->i_bh = NULL;
2033 list_del_init(&ii->i_dirty);
2034 if (!ii->vfs_inode.i_nlink || during_mount) {
2035 /*
2036 * Defer calling iput() to avoid deadlocks if
2037 * i_nlink == 0 or mount is not yet finished.
2038 */
2039 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue);
2040 defer_iput = true;
2041 } else {
2042 spin_unlock(&nilfs->ns_inode_lock);
2043 iput(&ii->vfs_inode);
2044 spin_lock(&nilfs->ns_inode_lock);
2045 }
2046 }
2047 spin_unlock(&nilfs->ns_inode_lock);
2048
2049 if (defer_iput)
2050 schedule_work(&sci->sc_iput_work);
2051 }
2052
2053 /*
2054 * Main procedure of segment constructor
2055 */
nilfs_segctor_do_construct(struct nilfs_sc_info * sci,int mode)2056 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
2057 {
2058 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2059 int err;
2060
2061 if (sb_rdonly(sci->sc_super))
2062 return -EROFS;
2063
2064 nilfs_sc_cstage_set(sci, NILFS_ST_INIT);
2065 sci->sc_cno = nilfs->ns_cno;
2066
2067 err = nilfs_segctor_collect_dirty_files(sci, nilfs);
2068 if (unlikely(err))
2069 goto out;
2070
2071 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root))
2072 set_bit(NILFS_SC_DIRTY, &sci->sc_flags);
2073
2074 if (nilfs_segctor_clean(sci))
2075 goto out;
2076
2077 do {
2078 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK;
2079
2080 err = nilfs_segctor_begin_construction(sci, nilfs);
2081 if (unlikely(err))
2082 goto out;
2083
2084 /* Update time stamp */
2085 sci->sc_seg_ctime = ktime_get_real_seconds();
2086
2087 err = nilfs_segctor_collect(sci, nilfs, mode);
2088 if (unlikely(err))
2089 goto failed;
2090
2091 /* Avoid empty segment */
2092 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE &&
2093 nilfs_segbuf_empty(sci->sc_curseg)) {
2094 nilfs_segctor_abort_construction(sci, nilfs, 1);
2095 goto out;
2096 }
2097
2098 err = nilfs_segctor_assign(sci, mode);
2099 if (unlikely(err))
2100 goto failed;
2101
2102 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2103 nilfs_segctor_fill_in_file_bmap(sci);
2104
2105 if (mode == SC_LSEG_SR &&
2106 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) {
2107 err = nilfs_segctor_fill_in_checkpoint(sci);
2108 if (unlikely(err))
2109 goto failed_to_write;
2110
2111 nilfs_segctor_fill_in_super_root(sci, nilfs);
2112 }
2113 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile);
2114
2115 /* Write partial segments */
2116 nilfs_segctor_prepare_write(sci);
2117
2118 nilfs_add_checksums_on_logs(&sci->sc_segbufs,
2119 nilfs->ns_crc_seed);
2120
2121 err = nilfs_segctor_write(sci, nilfs);
2122 if (unlikely(err))
2123 goto failed_to_write;
2124
2125 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
2126 nilfs->ns_blocksize_bits != PAGE_SHIFT) {
2127 /*
2128 * At this point, we avoid double buffering
2129 * for blocksize < pagesize because page dirty
2130 * flag is turned off during write and dirty
2131 * buffers are not properly collected for
2132 * pages crossing over segments.
2133 */
2134 err = nilfs_segctor_wait(sci);
2135 if (err)
2136 goto failed_to_write;
2137 }
2138 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE);
2139
2140 out:
2141 nilfs_segctor_drop_written_files(sci, nilfs);
2142 return err;
2143
2144 failed_to_write:
2145 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED)
2146 nilfs_redirty_inodes(&sci->sc_dirty_files);
2147
2148 failed:
2149 if (nilfs_doing_gc())
2150 nilfs_redirty_inodes(&sci->sc_gc_inodes);
2151 nilfs_segctor_abort_construction(sci, nilfs, err);
2152 goto out;
2153 }
2154
2155 /**
2156 * nilfs_segctor_start_timer - set timer of background write
2157 * @sci: nilfs_sc_info
2158 *
2159 * If the timer has already been set, it ignores the new request.
2160 * This function MUST be called within a section locking the segment
2161 * semaphore.
2162 */
nilfs_segctor_start_timer(struct nilfs_sc_info * sci)2163 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci)
2164 {
2165 spin_lock(&sci->sc_state_lock);
2166 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) {
2167 sci->sc_timer.expires = jiffies + sci->sc_interval;
2168 add_timer(&sci->sc_timer);
2169 sci->sc_state |= NILFS_SEGCTOR_COMMIT;
2170 }
2171 spin_unlock(&sci->sc_state_lock);
2172 }
2173
nilfs_segctor_do_flush(struct nilfs_sc_info * sci,int bn)2174 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn)
2175 {
2176 spin_lock(&sci->sc_state_lock);
2177 if (!(sci->sc_flush_request & BIT(bn))) {
2178 unsigned long prev_req = sci->sc_flush_request;
2179
2180 sci->sc_flush_request |= BIT(bn);
2181 if (!prev_req)
2182 wake_up(&sci->sc_wait_daemon);
2183 }
2184 spin_unlock(&sci->sc_state_lock);
2185 }
2186
2187 /**
2188 * nilfs_flush_segment - trigger a segment construction for resource control
2189 * @sb: super block
2190 * @ino: inode number of the file to be flushed out.
2191 */
nilfs_flush_segment(struct super_block * sb,ino_t ino)2192 void nilfs_flush_segment(struct super_block *sb, ino_t ino)
2193 {
2194 struct the_nilfs *nilfs = sb->s_fs_info;
2195 struct nilfs_sc_info *sci = nilfs->ns_writer;
2196
2197 if (!sci || nilfs_doing_construction())
2198 return;
2199 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0);
2200 /* assign bit 0 to data files */
2201 }
2202
2203 struct nilfs_segctor_wait_request {
2204 wait_queue_entry_t wq;
2205 __u32 seq;
2206 int err;
2207 atomic_t done;
2208 };
2209
nilfs_segctor_sync(struct nilfs_sc_info * sci)2210 static int nilfs_segctor_sync(struct nilfs_sc_info *sci)
2211 {
2212 struct nilfs_segctor_wait_request wait_req;
2213 int err = 0;
2214
2215 spin_lock(&sci->sc_state_lock);
2216 init_wait(&wait_req.wq);
2217 wait_req.err = 0;
2218 atomic_set(&wait_req.done, 0);
2219 wait_req.seq = ++sci->sc_seq_request;
2220 spin_unlock(&sci->sc_state_lock);
2221
2222 init_waitqueue_entry(&wait_req.wq, current);
2223 add_wait_queue(&sci->sc_wait_request, &wait_req.wq);
2224 set_current_state(TASK_INTERRUPTIBLE);
2225 wake_up(&sci->sc_wait_daemon);
2226
2227 for (;;) {
2228 if (atomic_read(&wait_req.done)) {
2229 err = wait_req.err;
2230 break;
2231 }
2232 if (!signal_pending(current)) {
2233 schedule();
2234 continue;
2235 }
2236 err = -ERESTARTSYS;
2237 break;
2238 }
2239 finish_wait(&sci->sc_wait_request, &wait_req.wq);
2240 return err;
2241 }
2242
nilfs_segctor_wakeup(struct nilfs_sc_info * sci,int err)2243 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
2244 {
2245 struct nilfs_segctor_wait_request *wrq, *n;
2246 unsigned long flags;
2247
2248 spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
2249 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
2250 if (!atomic_read(&wrq->done) &&
2251 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
2252 wrq->err = err;
2253 atomic_set(&wrq->done, 1);
2254 }
2255 if (atomic_read(&wrq->done)) {
2256 wrq->wq.func(&wrq->wq,
2257 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE,
2258 0, NULL);
2259 }
2260 }
2261 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags);
2262 }
2263
2264 /**
2265 * nilfs_construct_segment - construct a logical segment
2266 * @sb: super block
2267 *
2268 * Return Value: On success, 0 is retured. On errors, one of the following
2269 * negative error code is returned.
2270 *
2271 * %-EROFS - Read only filesystem.
2272 *
2273 * %-EIO - I/O error
2274 *
2275 * %-ENOSPC - No space left on device (only in a panic state).
2276 *
2277 * %-ERESTARTSYS - Interrupted.
2278 *
2279 * %-ENOMEM - Insufficient memory available.
2280 */
nilfs_construct_segment(struct super_block * sb)2281 int nilfs_construct_segment(struct super_block *sb)
2282 {
2283 struct the_nilfs *nilfs = sb->s_fs_info;
2284 struct nilfs_sc_info *sci = nilfs->ns_writer;
2285 struct nilfs_transaction_info *ti;
2286 int err;
2287
2288 if (sb_rdonly(sb) || unlikely(!sci))
2289 return -EROFS;
2290
2291 /* A call inside transactions causes a deadlock. */
2292 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC);
2293
2294 err = nilfs_segctor_sync(sci);
2295 return err;
2296 }
2297
2298 /**
2299 * nilfs_construct_dsync_segment - construct a data-only logical segment
2300 * @sb: super block
2301 * @inode: inode whose data blocks should be written out
2302 * @start: start byte offset
2303 * @end: end byte offset (inclusive)
2304 *
2305 * Return Value: On success, 0 is retured. On errors, one of the following
2306 * negative error code is returned.
2307 *
2308 * %-EROFS - Read only filesystem.
2309 *
2310 * %-EIO - I/O error
2311 *
2312 * %-ENOSPC - No space left on device (only in a panic state).
2313 *
2314 * %-ERESTARTSYS - Interrupted.
2315 *
2316 * %-ENOMEM - Insufficient memory available.
2317 */
nilfs_construct_dsync_segment(struct super_block * sb,struct inode * inode,loff_t start,loff_t end)2318 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
2319 loff_t start, loff_t end)
2320 {
2321 struct the_nilfs *nilfs = sb->s_fs_info;
2322 struct nilfs_sc_info *sci = nilfs->ns_writer;
2323 struct nilfs_inode_info *ii;
2324 struct nilfs_transaction_info ti;
2325 int err = 0;
2326
2327 if (sb_rdonly(sb) || unlikely(!sci))
2328 return -EROFS;
2329
2330 nilfs_transaction_lock(sb, &ti, 0);
2331
2332 ii = NILFS_I(inode);
2333 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) ||
2334 nilfs_test_opt(nilfs, STRICT_ORDER) ||
2335 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2336 nilfs_discontinued(nilfs)) {
2337 nilfs_transaction_unlock(sb);
2338 err = nilfs_segctor_sync(sci);
2339 return err;
2340 }
2341
2342 spin_lock(&nilfs->ns_inode_lock);
2343 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
2344 !test_bit(NILFS_I_BUSY, &ii->i_state)) {
2345 spin_unlock(&nilfs->ns_inode_lock);
2346 nilfs_transaction_unlock(sb);
2347 return 0;
2348 }
2349 spin_unlock(&nilfs->ns_inode_lock);
2350 sci->sc_dsync_inode = ii;
2351 sci->sc_dsync_start = start;
2352 sci->sc_dsync_end = end;
2353
2354 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);
2355 if (!err)
2356 nilfs->ns_flushed_device = 0;
2357
2358 nilfs_transaction_unlock(sb);
2359 return err;
2360 }
2361
2362 #define FLUSH_FILE_BIT (0x1) /* data file only */
2363 #define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */
2364
2365 /**
2366 * nilfs_segctor_accept - record accepted sequence count of log-write requests
2367 * @sci: segment constructor object
2368 */
nilfs_segctor_accept(struct nilfs_sc_info * sci)2369 static void nilfs_segctor_accept(struct nilfs_sc_info *sci)
2370 {
2371 spin_lock(&sci->sc_state_lock);
2372 sci->sc_seq_accepted = sci->sc_seq_request;
2373 spin_unlock(&sci->sc_state_lock);
2374 del_timer_sync(&sci->sc_timer);
2375 }
2376
2377 /**
2378 * nilfs_segctor_notify - notify the result of request to caller threads
2379 * @sci: segment constructor object
2380 * @mode: mode of log forming
2381 * @err: error code to be notified
2382 */
nilfs_segctor_notify(struct nilfs_sc_info * sci,int mode,int err)2383 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err)
2384 {
2385 /* Clear requests (even when the construction failed) */
2386 spin_lock(&sci->sc_state_lock);
2387
2388 if (mode == SC_LSEG_SR) {
2389 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT;
2390 sci->sc_seq_done = sci->sc_seq_accepted;
2391 nilfs_segctor_wakeup(sci, err);
2392 sci->sc_flush_request = 0;
2393 } else {
2394 if (mode == SC_FLUSH_FILE)
2395 sci->sc_flush_request &= ~FLUSH_FILE_BIT;
2396 else if (mode == SC_FLUSH_DAT)
2397 sci->sc_flush_request &= ~FLUSH_DAT_BIT;
2398
2399 /* re-enable timer if checkpoint creation was not done */
2400 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2401 time_before(jiffies, sci->sc_timer.expires))
2402 add_timer(&sci->sc_timer);
2403 }
2404 spin_unlock(&sci->sc_state_lock);
2405 }
2406
2407 /**
2408 * nilfs_segctor_construct - form logs and write them to disk
2409 * @sci: segment constructor object
2410 * @mode: mode of log forming
2411 */
nilfs_segctor_construct(struct nilfs_sc_info * sci,int mode)2412 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
2413 {
2414 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2415 struct nilfs_super_block **sbp;
2416 int err = 0;
2417
2418 nilfs_segctor_accept(sci);
2419
2420 if (nilfs_discontinued(nilfs))
2421 mode = SC_LSEG_SR;
2422 if (!nilfs_segctor_confirm(sci))
2423 err = nilfs_segctor_do_construct(sci, mode);
2424
2425 if (likely(!err)) {
2426 if (mode != SC_FLUSH_DAT)
2427 atomic_set(&nilfs->ns_ndirtyblks, 0);
2428 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
2429 nilfs_discontinued(nilfs)) {
2430 down_write(&nilfs->ns_sem);
2431 err = -EIO;
2432 sbp = nilfs_prepare_super(sci->sc_super,
2433 nilfs_sb_will_flip(nilfs));
2434 if (likely(sbp)) {
2435 nilfs_set_log_cursor(sbp[0], nilfs);
2436 err = nilfs_commit_super(sci->sc_super,
2437 NILFS_SB_COMMIT);
2438 }
2439 up_write(&nilfs->ns_sem);
2440 }
2441 }
2442
2443 nilfs_segctor_notify(sci, mode, err);
2444 return err;
2445 }
2446
nilfs_construction_timeout(struct timer_list * t)2447 static void nilfs_construction_timeout(struct timer_list *t)
2448 {
2449 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
2450
2451 wake_up_process(sci->sc_timer_task);
2452 }
2453
2454 static void
nilfs_remove_written_gcinodes(struct the_nilfs * nilfs,struct list_head * head)2455 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
2456 {
2457 struct nilfs_inode_info *ii, *n;
2458
2459 list_for_each_entry_safe(ii, n, head, i_dirty) {
2460 if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
2461 continue;
2462 list_del_init(&ii->i_dirty);
2463 truncate_inode_pages(&ii->vfs_inode.i_data, 0);
2464 nilfs_btnode_cache_clear(ii->i_assoc_inode->i_mapping);
2465 iput(&ii->vfs_inode);
2466 }
2467 }
2468
nilfs_clean_segments(struct super_block * sb,struct nilfs_argv * argv,void ** kbufs)2469 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
2470 void **kbufs)
2471 {
2472 struct the_nilfs *nilfs = sb->s_fs_info;
2473 struct nilfs_sc_info *sci = nilfs->ns_writer;
2474 struct nilfs_transaction_info ti;
2475 int err;
2476
2477 if (unlikely(!sci))
2478 return -EROFS;
2479
2480 nilfs_transaction_lock(sb, &ti, 1);
2481
2482 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat);
2483 if (unlikely(err))
2484 goto out_unlock;
2485
2486 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
2487 if (unlikely(err)) {
2488 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat);
2489 goto out_unlock;
2490 }
2491
2492 sci->sc_freesegs = kbufs[4];
2493 sci->sc_nfreesegs = argv[4].v_nmembs;
2494 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
2495
2496 for (;;) {
2497 err = nilfs_segctor_construct(sci, SC_LSEG_SR);
2498 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes);
2499
2500 if (likely(!err))
2501 break;
2502
2503 nilfs_warn(sb, "error %d cleaning segments", err);
2504 set_current_state(TASK_INTERRUPTIBLE);
2505 schedule_timeout(sci->sc_interval);
2506 }
2507 if (nilfs_test_opt(nilfs, DISCARD)) {
2508 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs,
2509 sci->sc_nfreesegs);
2510 if (ret) {
2511 nilfs_warn(sb,
2512 "error %d on discard request, turning discards off for the device",
2513 ret);
2514 nilfs_clear_opt(nilfs, DISCARD);
2515 }
2516 }
2517
2518 out_unlock:
2519 sci->sc_freesegs = NULL;
2520 sci->sc_nfreesegs = 0;
2521 nilfs_mdt_clear_shadow_map(nilfs->ns_dat);
2522 nilfs_transaction_unlock(sb);
2523 return err;
2524 }
2525
nilfs_segctor_thread_construct(struct nilfs_sc_info * sci,int mode)2526 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode)
2527 {
2528 struct nilfs_transaction_info ti;
2529
2530 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2531 nilfs_segctor_construct(sci, mode);
2532
2533 /*
2534 * Unclosed segment should be retried. We do this using sc_timer.
2535 * Timeout of sc_timer will invoke complete construction which leads
2536 * to close the current logical segment.
2537 */
2538 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags))
2539 nilfs_segctor_start_timer(sci);
2540
2541 nilfs_transaction_unlock(sci->sc_super);
2542 }
2543
nilfs_segctor_do_immediate_flush(struct nilfs_sc_info * sci)2544 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci)
2545 {
2546 int mode = 0;
2547
2548 spin_lock(&sci->sc_state_lock);
2549 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ?
2550 SC_FLUSH_DAT : SC_FLUSH_FILE;
2551 spin_unlock(&sci->sc_state_lock);
2552
2553 if (mode) {
2554 nilfs_segctor_do_construct(sci, mode);
2555
2556 spin_lock(&sci->sc_state_lock);
2557 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ?
2558 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT;
2559 spin_unlock(&sci->sc_state_lock);
2560 }
2561 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags);
2562 }
2563
nilfs_segctor_flush_mode(struct nilfs_sc_info * sci)2564 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci)
2565 {
2566 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) ||
2567 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) {
2568 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT))
2569 return SC_FLUSH_FILE;
2570 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT))
2571 return SC_FLUSH_DAT;
2572 }
2573 return SC_LSEG_SR;
2574 }
2575
2576 /**
2577 * nilfs_segctor_thread - main loop of the segment constructor thread.
2578 * @arg: pointer to a struct nilfs_sc_info.
2579 *
2580 * nilfs_segctor_thread() initializes a timer and serves as a daemon
2581 * to execute segment constructions.
2582 */
nilfs_segctor_thread(void * arg)2583 static int nilfs_segctor_thread(void *arg)
2584 {
2585 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg;
2586 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2587 int timeout = 0;
2588
2589 sci->sc_timer_task = current;
2590
2591 /* start sync. */
2592 sci->sc_task = current;
2593 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */
2594 nilfs_info(sci->sc_super,
2595 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds",
2596 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ);
2597
2598 spin_lock(&sci->sc_state_lock);
2599 loop:
2600 for (;;) {
2601 int mode;
2602
2603 if (sci->sc_state & NILFS_SEGCTOR_QUIT)
2604 goto end_thread;
2605
2606 if (timeout || sci->sc_seq_request != sci->sc_seq_done)
2607 mode = SC_LSEG_SR;
2608 else if (sci->sc_flush_request)
2609 mode = nilfs_segctor_flush_mode(sci);
2610 else
2611 break;
2612
2613 spin_unlock(&sci->sc_state_lock);
2614 nilfs_segctor_thread_construct(sci, mode);
2615 spin_lock(&sci->sc_state_lock);
2616 timeout = 0;
2617 }
2618
2619
2620 if (freezing(current)) {
2621 spin_unlock(&sci->sc_state_lock);
2622 try_to_freeze();
2623 spin_lock(&sci->sc_state_lock);
2624 } else {
2625 DEFINE_WAIT(wait);
2626 int should_sleep = 1;
2627
2628 prepare_to_wait(&sci->sc_wait_daemon, &wait,
2629 TASK_INTERRUPTIBLE);
2630
2631 if (sci->sc_seq_request != sci->sc_seq_done)
2632 should_sleep = 0;
2633 else if (sci->sc_flush_request)
2634 should_sleep = 0;
2635 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT)
2636 should_sleep = time_before(jiffies,
2637 sci->sc_timer.expires);
2638
2639 if (should_sleep) {
2640 spin_unlock(&sci->sc_state_lock);
2641 schedule();
2642 spin_lock(&sci->sc_state_lock);
2643 }
2644 finish_wait(&sci->sc_wait_daemon, &wait);
2645 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) &&
2646 time_after_eq(jiffies, sci->sc_timer.expires));
2647
2648 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs))
2649 set_nilfs_discontinued(nilfs);
2650 }
2651 goto loop;
2652
2653 end_thread:
2654 /* end sync. */
2655 sci->sc_task = NULL;
2656 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */
2657 spin_unlock(&sci->sc_state_lock);
2658 return 0;
2659 }
2660
nilfs_segctor_start_thread(struct nilfs_sc_info * sci)2661 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci)
2662 {
2663 struct task_struct *t;
2664
2665 t = kthread_run(nilfs_segctor_thread, sci, "segctord");
2666 if (IS_ERR(t)) {
2667 int err = PTR_ERR(t);
2668
2669 nilfs_err(sci->sc_super, "error %d creating segctord thread",
2670 err);
2671 return err;
2672 }
2673 wait_event(sci->sc_wait_task, sci->sc_task != NULL);
2674 return 0;
2675 }
2676
nilfs_segctor_kill_thread(struct nilfs_sc_info * sci)2677 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci)
2678 __acquires(&sci->sc_state_lock)
2679 __releases(&sci->sc_state_lock)
2680 {
2681 sci->sc_state |= NILFS_SEGCTOR_QUIT;
2682
2683 while (sci->sc_task) {
2684 wake_up(&sci->sc_wait_daemon);
2685 spin_unlock(&sci->sc_state_lock);
2686 wait_event(sci->sc_wait_task, sci->sc_task == NULL);
2687 spin_lock(&sci->sc_state_lock);
2688 }
2689 }
2690
2691 /*
2692 * Setup & clean-up functions
2693 */
nilfs_segctor_new(struct super_block * sb,struct nilfs_root * root)2694 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
2695 struct nilfs_root *root)
2696 {
2697 struct the_nilfs *nilfs = sb->s_fs_info;
2698 struct nilfs_sc_info *sci;
2699
2700 sci = kzalloc(sizeof(*sci), GFP_KERNEL);
2701 if (!sci)
2702 return NULL;
2703
2704 sci->sc_super = sb;
2705
2706 nilfs_get_root(root);
2707 sci->sc_root = root;
2708
2709 init_waitqueue_head(&sci->sc_wait_request);
2710 init_waitqueue_head(&sci->sc_wait_daemon);
2711 init_waitqueue_head(&sci->sc_wait_task);
2712 spin_lock_init(&sci->sc_state_lock);
2713 INIT_LIST_HEAD(&sci->sc_dirty_files);
2714 INIT_LIST_HEAD(&sci->sc_segbufs);
2715 INIT_LIST_HEAD(&sci->sc_write_logs);
2716 INIT_LIST_HEAD(&sci->sc_gc_inodes);
2717 INIT_LIST_HEAD(&sci->sc_iput_queue);
2718 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
2719 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
2720
2721 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
2722 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
2723 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK;
2724
2725 if (nilfs->ns_interval)
2726 sci->sc_interval = HZ * nilfs->ns_interval;
2727 if (nilfs->ns_watermark)
2728 sci->sc_watermark = nilfs->ns_watermark;
2729 return sci;
2730 }
2731
nilfs_segctor_write_out(struct nilfs_sc_info * sci)2732 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci)
2733 {
2734 int ret, retrycount = NILFS_SC_CLEANUP_RETRY;
2735
2736 /*
2737 * The segctord thread was stopped and its timer was removed.
2738 * But some tasks remain.
2739 */
2740 do {
2741 struct nilfs_transaction_info ti;
2742
2743 nilfs_transaction_lock(sci->sc_super, &ti, 0);
2744 ret = nilfs_segctor_construct(sci, SC_LSEG_SR);
2745 nilfs_transaction_unlock(sci->sc_super);
2746
2747 flush_work(&sci->sc_iput_work);
2748
2749 } while (ret && ret != -EROFS && retrycount-- > 0);
2750 }
2751
2752 /**
2753 * nilfs_segctor_destroy - destroy the segment constructor.
2754 * @sci: nilfs_sc_info
2755 *
2756 * nilfs_segctor_destroy() kills the segctord thread and frees
2757 * the nilfs_sc_info struct.
2758 * Caller must hold the segment semaphore.
2759 */
nilfs_segctor_destroy(struct nilfs_sc_info * sci)2760 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci)
2761 {
2762 struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
2763 int flag;
2764
2765 up_write(&nilfs->ns_segctor_sem);
2766
2767 spin_lock(&sci->sc_state_lock);
2768 nilfs_segctor_kill_thread(sci);
2769 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request
2770 || sci->sc_seq_request != sci->sc_seq_done);
2771 spin_unlock(&sci->sc_state_lock);
2772
2773 if (flush_work(&sci->sc_iput_work))
2774 flag = true;
2775
2776 if (flag || !nilfs_segctor_confirm(sci))
2777 nilfs_segctor_write_out(sci);
2778
2779 if (!list_empty(&sci->sc_dirty_files)) {
2780 nilfs_warn(sci->sc_super,
2781 "disposed unprocessed dirty file(s) when stopping log writer");
2782 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1);
2783 }
2784
2785 if (!list_empty(&sci->sc_iput_queue)) {
2786 nilfs_warn(sci->sc_super,
2787 "disposed unprocessed inode(s) in iput queue when stopping log writer");
2788 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1);
2789 }
2790
2791 WARN_ON(!list_empty(&sci->sc_segbufs));
2792 WARN_ON(!list_empty(&sci->sc_write_logs));
2793
2794 nilfs_put_root(sci->sc_root);
2795
2796 down_write(&nilfs->ns_segctor_sem);
2797
2798 del_timer_sync(&sci->sc_timer);
2799 kfree(sci);
2800 }
2801
2802 /**
2803 * nilfs_attach_log_writer - attach log writer
2804 * @sb: super block instance
2805 * @root: root object of the current filesystem tree
2806 *
2807 * This allocates a log writer object, initializes it, and starts the
2808 * log writer.
2809 *
2810 * Return Value: On success, 0 is returned. On error, one of the following
2811 * negative error code is returned.
2812 *
2813 * %-ENOMEM - Insufficient memory available.
2814 */
nilfs_attach_log_writer(struct super_block * sb,struct nilfs_root * root)2815 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
2816 {
2817 struct the_nilfs *nilfs = sb->s_fs_info;
2818 int err;
2819
2820 if (nilfs->ns_writer) {
2821 /*
2822 * This happens if the filesystem is made read-only by
2823 * __nilfs_error or nilfs_remount and then remounted
2824 * read/write. In these cases, reuse the existing
2825 * writer.
2826 */
2827 return 0;
2828 }
2829
2830 nilfs->ns_writer = nilfs_segctor_new(sb, root);
2831 if (!nilfs->ns_writer)
2832 return -ENOMEM;
2833
2834 inode_attach_wb(nilfs->ns_bdev->bd_inode, NULL);
2835
2836 err = nilfs_segctor_start_thread(nilfs->ns_writer);
2837 if (unlikely(err))
2838 nilfs_detach_log_writer(sb);
2839
2840 return err;
2841 }
2842
2843 /**
2844 * nilfs_detach_log_writer - destroy log writer
2845 * @sb: super block instance
2846 *
2847 * This kills log writer daemon, frees the log writer object, and
2848 * destroys list of dirty files.
2849 */
nilfs_detach_log_writer(struct super_block * sb)2850 void nilfs_detach_log_writer(struct super_block *sb)
2851 {
2852 struct the_nilfs *nilfs = sb->s_fs_info;
2853 LIST_HEAD(garbage_list);
2854
2855 down_write(&nilfs->ns_segctor_sem);
2856 if (nilfs->ns_writer) {
2857 nilfs_segctor_destroy(nilfs->ns_writer);
2858 nilfs->ns_writer = NULL;
2859 }
2860 set_nilfs_purging(nilfs);
2861
2862 /* Force to free the list of dirty files */
2863 spin_lock(&nilfs->ns_inode_lock);
2864 if (!list_empty(&nilfs->ns_dirty_files)) {
2865 list_splice_init(&nilfs->ns_dirty_files, &garbage_list);
2866 nilfs_warn(sb,
2867 "disposed unprocessed dirty file(s) when detaching log writer");
2868 }
2869 spin_unlock(&nilfs->ns_inode_lock);
2870 up_write(&nilfs->ns_segctor_sem);
2871
2872 nilfs_dispose_list(nilfs, &garbage_list, 1);
2873 clear_nilfs_purging(nilfs);
2874 }
2875