xref: /linux/fs/nilfs2/dat.c (revision 680e6ffa15103ab610c0fc1241d2f98c801b13e2) 
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * dat.c - NILFS disk address translation.
4  *
5  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
6  *
7  * Written by Koji Sato.
8  */
9 
10 #include <linux/types.h>
11 #include <linux/buffer_head.h>
12 #include <linux/string.h>
13 #include <linux/errno.h>
14 #include "nilfs.h"
15 #include "mdt.h"
16 #include "alloc.h"
17 #include "dat.h"
18 
19 
20 #define NILFS_CNO_MIN	((__u64)1)
21 #define NILFS_CNO_MAX	(~(__u64)0)
22 
23 /**
24  * struct nilfs_dat_info - on-memory private data of DAT file
25  * @mi: on-memory private data of metadata file
26  * @palloc_cache: persistent object allocator cache of DAT file
27  * @shadow: shadow map of DAT file
28  */
29 struct nilfs_dat_info {
30 	struct nilfs_mdt_info mi;
31 	struct nilfs_palloc_cache palloc_cache;
32 	struct nilfs_shadow_map shadow;
33 };
34 
35 static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
36 {
37 	return (struct nilfs_dat_info *)NILFS_MDT(dat);
38 }
39 
40 static int nilfs_dat_prepare_entry(struct inode *dat,
41 				   struct nilfs_palloc_req *req, int create)
42 {
43 	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
44 					    create, &req->pr_entry_bh);
45 }
46 
47 static void nilfs_dat_commit_entry(struct inode *dat,
48 				   struct nilfs_palloc_req *req)
49 {
50 	mark_buffer_dirty(req->pr_entry_bh);
51 	nilfs_mdt_mark_dirty(dat);
52 	brelse(req->pr_entry_bh);
53 }
54 
55 static void nilfs_dat_abort_entry(struct inode *dat,
56 				  struct nilfs_palloc_req *req)
57 {
58 	brelse(req->pr_entry_bh);
59 }
60 
61 int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
62 {
63 	int ret;
64 
65 	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
66 	if (ret < 0)
67 		return ret;
68 
69 	ret = nilfs_dat_prepare_entry(dat, req, 1);
70 	if (ret < 0)
71 		nilfs_palloc_abort_alloc_entry(dat, req);
72 
73 	return ret;
74 }
75 
76 void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
77 {
78 	struct nilfs_dat_entry *entry;
79 	void *kaddr;
80 
81 	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
82 	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
83 					     req->pr_entry_bh, kaddr);
84 	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
85 	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
86 	entry->de_blocknr = cpu_to_le64(0);
87 	kunmap_atomic(kaddr);
88 
89 	nilfs_palloc_commit_alloc_entry(dat, req);
90 	nilfs_dat_commit_entry(dat, req);
91 }
92 
93 void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
94 {
95 	nilfs_dat_abort_entry(dat, req);
96 	nilfs_palloc_abort_alloc_entry(dat, req);
97 }
98 
99 static void nilfs_dat_commit_free(struct inode *dat,
100 				  struct nilfs_palloc_req *req)
101 {
102 	struct nilfs_dat_entry *entry;
103 	void *kaddr;
104 
105 	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
106 	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
107 					     req->pr_entry_bh, kaddr);
108 	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
109 	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
110 	entry->de_blocknr = cpu_to_le64(0);
111 	kunmap_atomic(kaddr);
112 
113 	nilfs_dat_commit_entry(dat, req);
114 	nilfs_palloc_commit_free_entry(dat, req);
115 }
116 
117 int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
118 {
119 	int ret;
120 
121 	ret = nilfs_dat_prepare_entry(dat, req, 0);
122 	WARN_ON(ret == -ENOENT);
123 	return ret;
124 }
125 
126 void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
127 			    sector_t blocknr)
128 {
129 	struct nilfs_dat_entry *entry;
130 	void *kaddr;
131 
132 	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
133 	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
134 					     req->pr_entry_bh, kaddr);
135 	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
136 	entry->de_blocknr = cpu_to_le64(blocknr);
137 	kunmap_atomic(kaddr);
138 
139 	nilfs_dat_commit_entry(dat, req);
140 }
141 
142 int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
143 {
144 	struct nilfs_dat_entry *entry;
145 	sector_t blocknr;
146 	void *kaddr;
147 	int ret;
148 
149 	ret = nilfs_dat_prepare_entry(dat, req, 0);
150 	if (ret < 0) {
151 		WARN_ON(ret == -ENOENT);
152 		return ret;
153 	}
154 
155 	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
156 	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
157 					     req->pr_entry_bh, kaddr);
158 	blocknr = le64_to_cpu(entry->de_blocknr);
159 	kunmap_atomic(kaddr);
160 
161 	if (blocknr == 0) {
162 		ret = nilfs_palloc_prepare_free_entry(dat, req);
163 		if (ret < 0) {
164 			nilfs_dat_abort_entry(dat, req);
165 			return ret;
166 		}
167 	}
168 
169 	return 0;
170 }
171 
172 void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
173 			  int dead)
174 {
175 	struct nilfs_dat_entry *entry;
176 	__u64 start, end;
177 	sector_t blocknr;
178 	void *kaddr;
179 
180 	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
181 	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
182 					     req->pr_entry_bh, kaddr);
183 	end = start = le64_to_cpu(entry->de_start);
184 	if (!dead) {
185 		end = nilfs_mdt_cno(dat);
186 		WARN_ON(start > end);
187 	}
188 	entry->de_end = cpu_to_le64(end);
189 	blocknr = le64_to_cpu(entry->de_blocknr);
190 	kunmap_atomic(kaddr);
191 
192 	if (blocknr == 0)
193 		nilfs_dat_commit_free(dat, req);
194 	else
195 		nilfs_dat_commit_entry(dat, req);
196 }
197 
198 void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
199 {
200 	struct nilfs_dat_entry *entry;
201 	__u64 start;
202 	sector_t blocknr;
203 	void *kaddr;
204 
205 	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
206 	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
207 					     req->pr_entry_bh, kaddr);
208 	start = le64_to_cpu(entry->de_start);
209 	blocknr = le64_to_cpu(entry->de_blocknr);
210 	kunmap_atomic(kaddr);
211 
212 	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
213 		nilfs_palloc_abort_free_entry(dat, req);
214 	nilfs_dat_abort_entry(dat, req);
215 }
216 
217 int nilfs_dat_prepare_update(struct inode *dat,
218 			     struct nilfs_palloc_req *oldreq,
219 			     struct nilfs_palloc_req *newreq)
220 {
221 	int ret;
222 
223 	ret = nilfs_dat_prepare_end(dat, oldreq);
224 	if (!ret) {
225 		ret = nilfs_dat_prepare_alloc(dat, newreq);
226 		if (ret < 0)
227 			nilfs_dat_abort_end(dat, oldreq);
228 	}
229 	return ret;
230 }
231 
232 void nilfs_dat_commit_update(struct inode *dat,
233 			     struct nilfs_palloc_req *oldreq,
234 			     struct nilfs_palloc_req *newreq, int dead)
235 {
236 	nilfs_dat_commit_end(dat, oldreq, dead);
237 	nilfs_dat_commit_alloc(dat, newreq);
238 }
239 
240 void nilfs_dat_abort_update(struct inode *dat,
241 			    struct nilfs_palloc_req *oldreq,
242 			    struct nilfs_palloc_req *newreq)
243 {
244 	nilfs_dat_abort_end(dat, oldreq);
245 	nilfs_dat_abort_alloc(dat, newreq);
246 }
247 
248 /**
249  * nilfs_dat_mark_dirty -
250  * @dat: DAT file inode
251  * @vblocknr: virtual block number
252  *
253  * Description:
254  *
255  * Return Value: On success, 0 is returned. On error, one of the following
256  * negative error codes is returned.
257  *
258  * %-EIO - I/O error.
259  *
260  * %-ENOMEM - Insufficient amount of memory available.
261  */
262 int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
263 {
264 	struct nilfs_palloc_req req;
265 	int ret;
266 
267 	req.pr_entry_nr = vblocknr;
268 	ret = nilfs_dat_prepare_entry(dat, &req, 0);
269 	if (ret == 0)
270 		nilfs_dat_commit_entry(dat, &req);
271 	return ret;
272 }
273 
274 /**
275  * nilfs_dat_freev - free virtual block numbers
276  * @dat: DAT file inode
277  * @vblocknrs: array of virtual block numbers
278  * @nitems: number of virtual block numbers
279  *
280  * Description: nilfs_dat_freev() frees the virtual block numbers specified by
281  * @vblocknrs and @nitems.
282  *
283  * Return Value: On success, 0 is returned. On error, one of the following
284  * negative error codes is returned.
285  *
286  * %-EIO - I/O error.
287  *
288  * %-ENOMEM - Insufficient amount of memory available.
289  *
290  * %-ENOENT - The virtual block number have not been allocated.
291  */
292 int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
293 {
294 	return nilfs_palloc_freev(dat, vblocknrs, nitems);
295 }
296 
297 /**
298  * nilfs_dat_move - change a block number
299  * @dat: DAT file inode
300  * @vblocknr: virtual block number
301  * @blocknr: block number
302  *
303  * Description: nilfs_dat_move() changes the block number associated with
304  * @vblocknr to @blocknr.
305  *
306  * Return Value: On success, 0 is returned. On error, one of the following
307  * negative error codes is returned.
308  *
309  * %-EIO - I/O error.
310  *
311  * %-ENOMEM - Insufficient amount of memory available.
312  */
313 int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
314 {
315 	struct buffer_head *entry_bh;
316 	struct nilfs_dat_entry *entry;
317 	void *kaddr;
318 	int ret;
319 
320 	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
321 	if (ret < 0)
322 		return ret;
323 
324 	/*
325 	 * The given disk block number (blocknr) is not yet written to
326 	 * the device at this point.
327 	 *
328 	 * To prevent nilfs_dat_translate() from returning the
329 	 * uncommitted block number, this makes a copy of the entry
330 	 * buffer and redirects nilfs_dat_translate() to the copy.
331 	 */
332 	if (!buffer_nilfs_redirected(entry_bh)) {
333 		ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
334 		if (ret) {
335 			brelse(entry_bh);
336 			return ret;
337 		}
338 	}
339 
340 	kaddr = kmap_atomic(entry_bh->b_page);
341 	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
342 	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
343 		nilfs_msg(dat->i_sb, KERN_CRIT,
344 			  "%s: invalid vblocknr = %llu, [%llu, %llu)",
345 			  __func__, (unsigned long long)vblocknr,
346 			  (unsigned long long)le64_to_cpu(entry->de_start),
347 			  (unsigned long long)le64_to_cpu(entry->de_end));
348 		kunmap_atomic(kaddr);
349 		brelse(entry_bh);
350 		return -EINVAL;
351 	}
352 	WARN_ON(blocknr == 0);
353 	entry->de_blocknr = cpu_to_le64(blocknr);
354 	kunmap_atomic(kaddr);
355 
356 	mark_buffer_dirty(entry_bh);
357 	nilfs_mdt_mark_dirty(dat);
358 
359 	brelse(entry_bh);
360 
361 	return 0;
362 }
363 
364 /**
365  * nilfs_dat_translate - translate a virtual block number to a block number
366  * @dat: DAT file inode
367  * @vblocknr: virtual block number
368  * @blocknrp: pointer to a block number
369  *
370  * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
371  * to the corresponding block number.
372  *
373  * Return Value: On success, 0 is returned and the block number associated
374  * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
375  * of the following negative error codes is returned.
376  *
377  * %-EIO - I/O error.
378  *
379  * %-ENOMEM - Insufficient amount of memory available.
380  *
381  * %-ENOENT - A block number associated with @vblocknr does not exist.
382  */
383 int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
384 {
385 	struct buffer_head *entry_bh, *bh;
386 	struct nilfs_dat_entry *entry;
387 	sector_t blocknr;
388 	void *kaddr;
389 	int ret;
390 
391 	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
392 	if (ret < 0)
393 		return ret;
394 
395 	if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
396 		bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
397 		if (bh) {
398 			WARN_ON(!buffer_uptodate(bh));
399 			brelse(entry_bh);
400 			entry_bh = bh;
401 		}
402 	}
403 
404 	kaddr = kmap_atomic(entry_bh->b_page);
405 	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
406 	blocknr = le64_to_cpu(entry->de_blocknr);
407 	if (blocknr == 0) {
408 		ret = -ENOENT;
409 		goto out;
410 	}
411 	*blocknrp = blocknr;
412 
413  out:
414 	kunmap_atomic(kaddr);
415 	brelse(entry_bh);
416 	return ret;
417 }
418 
419 ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned int visz,
420 			    size_t nvi)
421 {
422 	struct buffer_head *entry_bh;
423 	struct nilfs_dat_entry *entry;
424 	struct nilfs_vinfo *vinfo = buf;
425 	__u64 first, last;
426 	void *kaddr;
427 	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
428 	int i, j, n, ret;
429 
430 	for (i = 0; i < nvi; i += n) {
431 		ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
432 						   0, &entry_bh);
433 		if (ret < 0)
434 			return ret;
435 		kaddr = kmap_atomic(entry_bh->b_page);
436 		/* last virtual block number in this block */
437 		first = vinfo->vi_vblocknr;
438 		do_div(first, entries_per_block);
439 		first *= entries_per_block;
440 		last = first + entries_per_block - 1;
441 		for (j = i, n = 0;
442 		     j < nvi && vinfo->vi_vblocknr >= first &&
443 			     vinfo->vi_vblocknr <= last;
444 		     j++, n++, vinfo = (void *)vinfo + visz) {
445 			entry = nilfs_palloc_block_get_entry(
446 				dat, vinfo->vi_vblocknr, entry_bh, kaddr);
447 			vinfo->vi_start = le64_to_cpu(entry->de_start);
448 			vinfo->vi_end = le64_to_cpu(entry->de_end);
449 			vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
450 		}
451 		kunmap_atomic(kaddr);
452 		brelse(entry_bh);
453 	}
454 
455 	return nvi;
456 }
457 
458 /**
459  * nilfs_dat_read - read or get dat inode
460  * @sb: super block instance
461  * @entry_size: size of a dat entry
462  * @raw_inode: on-disk dat inode
463  * @inodep: buffer to store the inode
464  */
465 int nilfs_dat_read(struct super_block *sb, size_t entry_size,
466 		   struct nilfs_inode *raw_inode, struct inode **inodep)
467 {
468 	static struct lock_class_key dat_lock_key;
469 	struct inode *dat;
470 	struct nilfs_dat_info *di;
471 	int err;
472 
473 	if (entry_size > sb->s_blocksize) {
474 		nilfs_msg(sb, KERN_ERR, "too large DAT entry size: %zu bytes",
475 			  entry_size);
476 		return -EINVAL;
477 	} else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
478 		nilfs_msg(sb, KERN_ERR, "too small DAT entry size: %zu bytes",
479 			  entry_size);
480 		return -EINVAL;
481 	}
482 
483 	dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
484 	if (unlikely(!dat))
485 		return -ENOMEM;
486 	if (!(dat->i_state & I_NEW))
487 		goto out;
488 
489 	err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
490 	if (err)
491 		goto failed;
492 
493 	err = nilfs_palloc_init_blockgroup(dat, entry_size);
494 	if (err)
495 		goto failed;
496 
497 	di = NILFS_DAT_I(dat);
498 	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
499 	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
500 	nilfs_mdt_setup_shadow_map(dat, &di->shadow);
501 
502 	err = nilfs_read_inode_common(dat, raw_inode);
503 	if (err)
504 		goto failed;
505 
506 	unlock_new_inode(dat);
507  out:
508 	*inodep = dat;
509 	return 0;
510  failed:
511 	iget_failed(dat);
512 	return err;
513 }
514