1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * NILFS segment buffer |
4 | * |
5 | * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. |
6 | * |
7 | * Written by Ryusuke Konishi. |
8 | * |
9 | */ |
10 | |
11 | #include <linux/buffer_head.h> |
12 | #include <linux/writeback.h> |
13 | #include <linux/crc32.h> |
14 | #include <linux/backing-dev.h> |
15 | #include <linux/slab.h> |
16 | #include "page.h" |
17 | #include "segbuf.h" |
18 | |
19 | |
20 | struct nilfs_write_info { |
21 | struct the_nilfs *nilfs; |
22 | struct bio *bio; |
23 | int start, end; /* The region to be submitted */ |
24 | int rest_blocks; |
25 | int max_pages; |
26 | int nr_vecs; |
27 | sector_t blocknr; |
28 | }; |
29 | |
30 | static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf, |
31 | struct the_nilfs *nilfs); |
32 | static int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf); |
33 | |
34 | struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *sb) |
35 | { |
36 | struct nilfs_segment_buffer *segbuf; |
37 | |
38 | segbuf = kmem_cache_alloc(cachep: nilfs_segbuf_cachep, GFP_NOFS); |
39 | if (unlikely(!segbuf)) |
40 | return NULL; |
41 | |
42 | segbuf->sb_super = sb; |
43 | INIT_LIST_HEAD(list: &segbuf->sb_list); |
44 | INIT_LIST_HEAD(list: &segbuf->sb_segsum_buffers); |
45 | INIT_LIST_HEAD(list: &segbuf->sb_payload_buffers); |
46 | segbuf->sb_super_root = NULL; |
47 | |
48 | init_completion(x: &segbuf->sb_bio_event); |
49 | atomic_set(v: &segbuf->sb_err, i: 0); |
50 | segbuf->sb_nbio = 0; |
51 | |
52 | return segbuf; |
53 | } |
54 | |
55 | void nilfs_segbuf_free(struct nilfs_segment_buffer *segbuf) |
56 | { |
57 | kmem_cache_free(s: nilfs_segbuf_cachep, objp: segbuf); |
58 | } |
59 | |
60 | void nilfs_segbuf_map(struct nilfs_segment_buffer *segbuf, __u64 segnum, |
61 | unsigned long offset, struct the_nilfs *nilfs) |
62 | { |
63 | segbuf->sb_segnum = segnum; |
64 | nilfs_get_segment_range(nilfs, segnum, seg_start: &segbuf->sb_fseg_start, |
65 | seg_end: &segbuf->sb_fseg_end); |
66 | |
67 | segbuf->sb_pseg_start = segbuf->sb_fseg_start + offset; |
68 | segbuf->sb_rest_blocks = |
69 | segbuf->sb_fseg_end - segbuf->sb_pseg_start + 1; |
70 | } |
71 | |
72 | /** |
73 | * nilfs_segbuf_map_cont - map a new log behind a given log |
74 | * @segbuf: new segment buffer |
75 | * @prev: segment buffer containing a log to be continued |
76 | */ |
77 | void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf, |
78 | struct nilfs_segment_buffer *prev) |
79 | { |
80 | segbuf->sb_segnum = prev->sb_segnum; |
81 | segbuf->sb_fseg_start = prev->sb_fseg_start; |
82 | segbuf->sb_fseg_end = prev->sb_fseg_end; |
83 | segbuf->sb_pseg_start = prev->sb_pseg_start + prev->sb_sum.nblocks; |
84 | segbuf->sb_rest_blocks = |
85 | segbuf->sb_fseg_end - segbuf->sb_pseg_start + 1; |
86 | } |
87 | |
88 | void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *segbuf, |
89 | __u64 nextnum, struct the_nilfs *nilfs) |
90 | { |
91 | segbuf->sb_nextnum = nextnum; |
92 | segbuf->sb_sum.next = nilfs_get_segment_start_blocknr(nilfs, segnum: nextnum); |
93 | } |
94 | |
95 | int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *segbuf) |
96 | { |
97 | struct buffer_head *bh; |
98 | |
99 | bh = sb_getblk(sb: segbuf->sb_super, |
100 | block: segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk); |
101 | if (unlikely(!bh)) |
102 | return -ENOMEM; |
103 | |
104 | lock_buffer(bh); |
105 | if (!buffer_uptodate(bh)) { |
106 | memset(bh->b_data, 0, bh->b_size); |
107 | set_buffer_uptodate(bh); |
108 | } |
109 | unlock_buffer(bh); |
110 | nilfs_segbuf_add_segsum_buffer(segbuf, bh); |
111 | return 0; |
112 | } |
113 | |
114 | int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *segbuf, |
115 | struct buffer_head **bhp) |
116 | { |
117 | struct buffer_head *bh; |
118 | |
119 | bh = sb_getblk(sb: segbuf->sb_super, |
120 | block: segbuf->sb_pseg_start + segbuf->sb_sum.nblocks); |
121 | if (unlikely(!bh)) |
122 | return -ENOMEM; |
123 | |
124 | nilfs_segbuf_add_payload_buffer(segbuf, bh); |
125 | *bhp = bh; |
126 | return 0; |
127 | } |
128 | |
129 | int nilfs_segbuf_reset(struct nilfs_segment_buffer *segbuf, unsigned int flags, |
130 | time64_t ctime, __u64 cno) |
131 | { |
132 | int err; |
133 | |
134 | segbuf->sb_sum.nblocks = segbuf->sb_sum.nsumblk = 0; |
135 | err = nilfs_segbuf_extend_segsum(segbuf); |
136 | if (unlikely(err)) |
137 | return err; |
138 | |
139 | segbuf->sb_sum.flags = flags; |
140 | segbuf->sb_sum.sumbytes = sizeof(struct nilfs_segment_summary); |
141 | segbuf->sb_sum.nfinfo = segbuf->sb_sum.nfileblk = 0; |
142 | segbuf->sb_sum.ctime = ctime; |
143 | segbuf->sb_sum.cno = cno; |
144 | return 0; |
145 | } |
146 | |
147 | /* |
148 | * Setup segment summary |
149 | */ |
150 | void nilfs_segbuf_fill_in_segsum(struct nilfs_segment_buffer *segbuf) |
151 | { |
152 | struct nilfs_segment_summary *raw_sum; |
153 | struct buffer_head *bh_sum; |
154 | |
155 | bh_sum = list_entry(segbuf->sb_segsum_buffers.next, |
156 | struct buffer_head, b_assoc_buffers); |
157 | raw_sum = (struct nilfs_segment_summary *)bh_sum->b_data; |
158 | |
159 | raw_sum->ss_magic = cpu_to_le32(NILFS_SEGSUM_MAGIC); |
160 | raw_sum->ss_bytes = cpu_to_le16(sizeof(*raw_sum)); |
161 | raw_sum->ss_flags = cpu_to_le16(segbuf->sb_sum.flags); |
162 | raw_sum->ss_seq = cpu_to_le64(segbuf->sb_sum.seg_seq); |
163 | raw_sum->ss_create = cpu_to_le64(segbuf->sb_sum.ctime); |
164 | raw_sum->ss_next = cpu_to_le64(segbuf->sb_sum.next); |
165 | raw_sum->ss_nblocks = cpu_to_le32(segbuf->sb_sum.nblocks); |
166 | raw_sum->ss_nfinfo = cpu_to_le32(segbuf->sb_sum.nfinfo); |
167 | raw_sum->ss_sumbytes = cpu_to_le32(segbuf->sb_sum.sumbytes); |
168 | raw_sum->ss_pad = 0; |
169 | raw_sum->ss_cno = cpu_to_le64(segbuf->sb_sum.cno); |
170 | } |
171 | |
172 | /* |
173 | * CRC calculation routines |
174 | */ |
175 | static void |
176 | nilfs_segbuf_fill_in_segsum_crc(struct nilfs_segment_buffer *segbuf, u32 seed) |
177 | { |
178 | struct buffer_head *bh; |
179 | struct nilfs_segment_summary *raw_sum; |
180 | unsigned long size, bytes = segbuf->sb_sum.sumbytes; |
181 | u32 crc; |
182 | |
183 | bh = list_entry(segbuf->sb_segsum_buffers.next, struct buffer_head, |
184 | b_assoc_buffers); |
185 | |
186 | raw_sum = (struct nilfs_segment_summary *)bh->b_data; |
187 | size = min_t(unsigned long, bytes, bh->b_size); |
188 | crc = crc32_le(crc: seed, |
189 | p: (unsigned char *)raw_sum + |
190 | sizeof(raw_sum->ss_datasum) + sizeof(raw_sum->ss_sumsum), |
191 | len: size - (sizeof(raw_sum->ss_datasum) + |
192 | sizeof(raw_sum->ss_sumsum))); |
193 | |
194 | list_for_each_entry_continue(bh, &segbuf->sb_segsum_buffers, |
195 | b_assoc_buffers) { |
196 | bytes -= size; |
197 | size = min_t(unsigned long, bytes, bh->b_size); |
198 | crc = crc32_le(crc, p: bh->b_data, len: size); |
199 | } |
200 | raw_sum->ss_sumsum = cpu_to_le32(crc); |
201 | } |
202 | |
203 | static void nilfs_segbuf_fill_in_data_crc(struct nilfs_segment_buffer *segbuf, |
204 | u32 seed) |
205 | { |
206 | struct buffer_head *bh; |
207 | struct nilfs_segment_summary *raw_sum; |
208 | void *kaddr; |
209 | u32 crc; |
210 | |
211 | bh = list_entry(segbuf->sb_segsum_buffers.next, struct buffer_head, |
212 | b_assoc_buffers); |
213 | raw_sum = (struct nilfs_segment_summary *)bh->b_data; |
214 | crc = crc32_le(crc: seed, |
215 | p: (unsigned char *)raw_sum + sizeof(raw_sum->ss_datasum), |
216 | len: bh->b_size - sizeof(raw_sum->ss_datasum)); |
217 | |
218 | list_for_each_entry_continue(bh, &segbuf->sb_segsum_buffers, |
219 | b_assoc_buffers) { |
220 | crc = crc32_le(crc, p: bh->b_data, len: bh->b_size); |
221 | } |
222 | list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { |
223 | kaddr = kmap_atomic(page: bh->b_page); |
224 | crc = crc32_le(crc, p: kaddr + bh_offset(bh), len: bh->b_size); |
225 | kunmap_atomic(kaddr); |
226 | } |
227 | raw_sum->ss_datasum = cpu_to_le32(crc); |
228 | } |
229 | |
230 | static void |
231 | nilfs_segbuf_fill_in_super_root_crc(struct nilfs_segment_buffer *segbuf, |
232 | u32 seed) |
233 | { |
234 | struct nilfs_super_root *raw_sr; |
235 | struct the_nilfs *nilfs = segbuf->sb_super->s_fs_info; |
236 | unsigned int srsize; |
237 | u32 crc; |
238 | |
239 | raw_sr = (struct nilfs_super_root *)segbuf->sb_super_root->b_data; |
240 | srsize = NILFS_SR_BYTES(nilfs->ns_inode_size); |
241 | crc = crc32_le(crc: seed, |
242 | p: (unsigned char *)raw_sr + sizeof(raw_sr->sr_sum), |
243 | len: srsize - sizeof(raw_sr->sr_sum)); |
244 | raw_sr->sr_sum = cpu_to_le32(crc); |
245 | } |
246 | |
247 | static void nilfs_release_buffers(struct list_head *list) |
248 | { |
249 | struct buffer_head *bh, *n; |
250 | |
251 | list_for_each_entry_safe(bh, n, list, b_assoc_buffers) { |
252 | list_del_init(entry: &bh->b_assoc_buffers); |
253 | brelse(bh); |
254 | } |
255 | } |
256 | |
257 | static void nilfs_segbuf_clear(struct nilfs_segment_buffer *segbuf) |
258 | { |
259 | nilfs_release_buffers(list: &segbuf->sb_segsum_buffers); |
260 | nilfs_release_buffers(list: &segbuf->sb_payload_buffers); |
261 | segbuf->sb_super_root = NULL; |
262 | } |
263 | |
264 | /* |
265 | * Iterators for segment buffers |
266 | */ |
267 | void nilfs_clear_logs(struct list_head *logs) |
268 | { |
269 | struct nilfs_segment_buffer *segbuf; |
270 | |
271 | list_for_each_entry(segbuf, logs, sb_list) |
272 | nilfs_segbuf_clear(segbuf); |
273 | } |
274 | |
275 | void nilfs_truncate_logs(struct list_head *logs, |
276 | struct nilfs_segment_buffer *last) |
277 | { |
278 | struct nilfs_segment_buffer *n, *segbuf; |
279 | |
280 | segbuf = list_prepare_entry(last, logs, sb_list); |
281 | list_for_each_entry_safe_continue(segbuf, n, logs, sb_list) { |
282 | list_del_init(entry: &segbuf->sb_list); |
283 | nilfs_segbuf_clear(segbuf); |
284 | nilfs_segbuf_free(segbuf); |
285 | } |
286 | } |
287 | |
288 | int nilfs_write_logs(struct list_head *logs, struct the_nilfs *nilfs) |
289 | { |
290 | struct nilfs_segment_buffer *segbuf; |
291 | int ret = 0; |
292 | |
293 | list_for_each_entry(segbuf, logs, sb_list) { |
294 | ret = nilfs_segbuf_write(segbuf, nilfs); |
295 | if (ret) |
296 | break; |
297 | } |
298 | return ret; |
299 | } |
300 | |
301 | int nilfs_wait_on_logs(struct list_head *logs) |
302 | { |
303 | struct nilfs_segment_buffer *segbuf; |
304 | int err, ret = 0; |
305 | |
306 | list_for_each_entry(segbuf, logs, sb_list) { |
307 | err = nilfs_segbuf_wait(segbuf); |
308 | if (err && !ret) |
309 | ret = err; |
310 | } |
311 | return ret; |
312 | } |
313 | |
314 | /** |
315 | * nilfs_add_checksums_on_logs - add checksums on the logs |
316 | * @logs: list of segment buffers storing target logs |
317 | * @seed: checksum seed value |
318 | */ |
319 | void nilfs_add_checksums_on_logs(struct list_head *logs, u32 seed) |
320 | { |
321 | struct nilfs_segment_buffer *segbuf; |
322 | |
323 | list_for_each_entry(segbuf, logs, sb_list) { |
324 | if (segbuf->sb_super_root) |
325 | nilfs_segbuf_fill_in_super_root_crc(segbuf, seed); |
326 | nilfs_segbuf_fill_in_segsum_crc(segbuf, seed); |
327 | nilfs_segbuf_fill_in_data_crc(segbuf, seed); |
328 | } |
329 | } |
330 | |
331 | /* |
332 | * BIO operations |
333 | */ |
334 | static void nilfs_end_bio_write(struct bio *bio) |
335 | { |
336 | struct nilfs_segment_buffer *segbuf = bio->bi_private; |
337 | |
338 | if (bio->bi_status) |
339 | atomic_inc(v: &segbuf->sb_err); |
340 | |
341 | bio_put(bio); |
342 | complete(&segbuf->sb_bio_event); |
343 | } |
344 | |
345 | static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf, |
346 | struct nilfs_write_info *wi) |
347 | { |
348 | struct bio *bio = wi->bio; |
349 | |
350 | bio->bi_end_io = nilfs_end_bio_write; |
351 | bio->bi_private = segbuf; |
352 | submit_bio(bio); |
353 | segbuf->sb_nbio++; |
354 | |
355 | wi->bio = NULL; |
356 | wi->rest_blocks -= wi->end - wi->start; |
357 | wi->nr_vecs = min(wi->max_pages, wi->rest_blocks); |
358 | wi->start = wi->end; |
359 | return 0; |
360 | } |
361 | |
362 | static void nilfs_segbuf_prepare_write(struct nilfs_segment_buffer *segbuf, |
363 | struct nilfs_write_info *wi) |
364 | { |
365 | wi->bio = NULL; |
366 | wi->rest_blocks = segbuf->sb_sum.nblocks; |
367 | wi->max_pages = BIO_MAX_VECS; |
368 | wi->nr_vecs = min(wi->max_pages, wi->rest_blocks); |
369 | wi->start = wi->end = 0; |
370 | wi->blocknr = segbuf->sb_pseg_start; |
371 | } |
372 | |
373 | static int nilfs_segbuf_submit_bh(struct nilfs_segment_buffer *segbuf, |
374 | struct nilfs_write_info *wi, |
375 | struct buffer_head *bh) |
376 | { |
377 | int len, err; |
378 | |
379 | BUG_ON(wi->nr_vecs <= 0); |
380 | repeat: |
381 | if (!wi->bio) { |
382 | wi->bio = bio_alloc(bdev: wi->nilfs->ns_bdev, nr_vecs: wi->nr_vecs, |
383 | opf: REQ_OP_WRITE, GFP_NOIO); |
384 | wi->bio->bi_iter.bi_sector = (wi->blocknr + wi->end) << |
385 | (wi->nilfs->ns_blocksize_bits - 9); |
386 | } |
387 | |
388 | len = bio_add_page(bio: wi->bio, page: bh->b_page, len: bh->b_size, off: bh_offset(bh)); |
389 | if (len == bh->b_size) { |
390 | wi->end++; |
391 | return 0; |
392 | } |
393 | /* bio is FULL */ |
394 | err = nilfs_segbuf_submit_bio(segbuf, wi); |
395 | /* never submit current bh */ |
396 | if (likely(!err)) |
397 | goto repeat; |
398 | return err; |
399 | } |
400 | |
401 | /** |
402 | * nilfs_segbuf_write - submit write requests of a log |
403 | * @segbuf: buffer storing a log to be written |
404 | * @nilfs: nilfs object |
405 | * |
406 | * Return Value: On Success, 0 is returned. On Error, one of the following |
407 | * negative error code is returned. |
408 | * |
409 | * %-EIO - I/O error |
410 | * |
411 | * %-ENOMEM - Insufficient memory available. |
412 | */ |
413 | static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf, |
414 | struct the_nilfs *nilfs) |
415 | { |
416 | struct nilfs_write_info wi; |
417 | struct buffer_head *bh; |
418 | int res = 0; |
419 | |
420 | wi.nilfs = nilfs; |
421 | nilfs_segbuf_prepare_write(segbuf, wi: &wi); |
422 | |
423 | list_for_each_entry(bh, &segbuf->sb_segsum_buffers, b_assoc_buffers) { |
424 | res = nilfs_segbuf_submit_bh(segbuf, wi: &wi, bh); |
425 | if (unlikely(res)) |
426 | goto failed_bio; |
427 | } |
428 | |
429 | list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { |
430 | res = nilfs_segbuf_submit_bh(segbuf, wi: &wi, bh); |
431 | if (unlikely(res)) |
432 | goto failed_bio; |
433 | } |
434 | |
435 | if (wi.bio) { |
436 | /* |
437 | * Last BIO is always sent through the following |
438 | * submission. |
439 | */ |
440 | wi.bio->bi_opf |= REQ_SYNC; |
441 | res = nilfs_segbuf_submit_bio(segbuf, wi: &wi); |
442 | } |
443 | |
444 | failed_bio: |
445 | return res; |
446 | } |
447 | |
448 | /** |
449 | * nilfs_segbuf_wait - wait for completion of requested BIOs |
450 | * @segbuf: segment buffer |
451 | * |
452 | * Return Value: On Success, 0 is returned. On Error, one of the following |
453 | * negative error code is returned. |
454 | * |
455 | * %-EIO - I/O error |
456 | */ |
457 | static int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf) |
458 | { |
459 | int err = 0; |
460 | |
461 | if (!segbuf->sb_nbio) |
462 | return 0; |
463 | |
464 | do { |
465 | wait_for_completion(&segbuf->sb_bio_event); |
466 | } while (--segbuf->sb_nbio > 0); |
467 | |
468 | if (unlikely(atomic_read(&segbuf->sb_err) > 0)) { |
469 | nilfs_err(segbuf->sb_super, |
470 | "I/O error writing log (start-blocknr=%llu, block-count=%lu) in segment %llu" , |
471 | (unsigned long long)segbuf->sb_pseg_start, |
472 | segbuf->sb_sum.nblocks, |
473 | (unsigned long long)segbuf->sb_segnum); |
474 | err = -EIO; |
475 | } |
476 | return err; |
477 | } |
478 | |