1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * NILFS block mapping.
4  *
5  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
6  *
7  * Written by Koji Sato.
8  */
9 
10 #include <linux/fs.h>
11 #include <linux/string.h>
12 #include <linux/errno.h>
13 #include "nilfs.h"
14 #include "bmap.h"
15 #include "btree.h"
16 #include "direct.h"
17 #include "btnode.h"
18 #include "mdt.h"
19 #include "dat.h"
20 #include "alloc.h"
21 
nilfs_bmap_get_dat(const struct nilfs_bmap * bmap)22 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap)
23 {
24 	struct the_nilfs *nilfs = bmap->b_inode->i_sb->s_fs_info;
25 
26 	return nilfs->ns_dat;
27 }
28 
nilfs_bmap_convert_error(struct nilfs_bmap * bmap,const char * fname,int err)29 static int nilfs_bmap_convert_error(struct nilfs_bmap *bmap,
30 				     const char *fname, int err)
31 {
32 	struct inode *inode = bmap->b_inode;
33 
34 	if (err == -EINVAL) {
35 		__nilfs_error(inode->i_sb, fname,
36 			      "broken bmap (inode number=%lu)", inode->i_ino);
37 		err = -EIO;
38 	}
39 	return err;
40 }
41 
42 /**
43  * nilfs_bmap_lookup_at_level - find a data block or node block
44  * @bmap: bmap
45  * @key: key
46  * @level: level
47  * @ptrp: place to store the value associated to @key
48  *
49  * Description: nilfs_bmap_lookup_at_level() finds a record whose key
50  * matches @key in the block at @level of the bmap.
51  *
52  * Return Value: On success, 0 is returned and the record associated with @key
53  * is stored in the place pointed by @ptrp. On error, one of the following
54  * negative error codes is returned.
55  *
56  * %-EIO - I/O error.
57  *
58  * %-ENOMEM - Insufficient amount of memory available.
59  *
60  * %-ENOENT - A record associated with @key does not exist.
61  */
nilfs_bmap_lookup_at_level(struct nilfs_bmap * bmap,__u64 key,int level,__u64 * ptrp)62 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *bmap, __u64 key, int level,
63 			       __u64 *ptrp)
64 {
65 	sector_t blocknr;
66 	int ret;
67 
68 	down_read(&bmap->b_sem);
69 	ret = bmap->b_ops->bop_lookup(bmap, key, level, ptrp);
70 	if (ret < 0) {
71 		ret = nilfs_bmap_convert_error(bmap, __func__, ret);
72 		goto out;
73 	}
74 	if (NILFS_BMAP_USE_VBN(bmap)) {
75 		ret = nilfs_dat_translate(nilfs_bmap_get_dat(bmap), *ptrp,
76 					  &blocknr);
77 		if (!ret)
78 			*ptrp = blocknr;
79 	}
80 
81  out:
82 	up_read(&bmap->b_sem);
83 	return ret;
84 }
85 
nilfs_bmap_lookup_contig(struct nilfs_bmap * bmap,__u64 key,__u64 * ptrp,unsigned int maxblocks)86 int nilfs_bmap_lookup_contig(struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp,
87 			     unsigned int maxblocks)
88 {
89 	int ret;
90 
91 	down_read(&bmap->b_sem);
92 	ret = bmap->b_ops->bop_lookup_contig(bmap, key, ptrp, maxblocks);
93 	up_read(&bmap->b_sem);
94 
95 	return nilfs_bmap_convert_error(bmap, __func__, ret);
96 }
97 
nilfs_bmap_do_insert(struct nilfs_bmap * bmap,__u64 key,__u64 ptr)98 static int nilfs_bmap_do_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
99 {
100 	__u64 keys[NILFS_BMAP_SMALL_HIGH + 1];
101 	__u64 ptrs[NILFS_BMAP_SMALL_HIGH + 1];
102 	int ret, n;
103 
104 	if (bmap->b_ops->bop_check_insert != NULL) {
105 		ret = bmap->b_ops->bop_check_insert(bmap, key);
106 		if (ret > 0) {
107 			n = bmap->b_ops->bop_gather_data(
108 				bmap, keys, ptrs, NILFS_BMAP_SMALL_HIGH + 1);
109 			if (n < 0)
110 				return n;
111 			ret = nilfs_btree_convert_and_insert(
112 				bmap, key, ptr, keys, ptrs, n);
113 			if (ret == 0)
114 				bmap->b_u.u_flags |= NILFS_BMAP_LARGE;
115 
116 			return ret;
117 		} else if (ret < 0)
118 			return ret;
119 	}
120 
121 	return bmap->b_ops->bop_insert(bmap, key, ptr);
122 }
123 
124 /**
125  * nilfs_bmap_insert - insert a new key-record pair into a bmap
126  * @bmap: bmap
127  * @key: key
128  * @rec: record
129  *
130  * Description: nilfs_bmap_insert() inserts the new key-record pair specified
131  * by @key and @rec into @bmap.
132  *
133  * Return Value: On success, 0 is returned. On error, one of the following
134  * negative error codes is returned.
135  *
136  * %-EIO - I/O error.
137  *
138  * %-ENOMEM - Insufficient amount of memory available.
139  *
140  * %-EEXIST - A record associated with @key already exist.
141  */
nilfs_bmap_insert(struct nilfs_bmap * bmap,__u64 key,unsigned long rec)142 int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec)
143 {
144 	int ret;
145 
146 	down_write(&bmap->b_sem);
147 	ret = nilfs_bmap_do_insert(bmap, key, rec);
148 	up_write(&bmap->b_sem);
149 
150 	return nilfs_bmap_convert_error(bmap, __func__, ret);
151 }
152 
nilfs_bmap_do_delete(struct nilfs_bmap * bmap,__u64 key)153 static int nilfs_bmap_do_delete(struct nilfs_bmap *bmap, __u64 key)
154 {
155 	__u64 keys[NILFS_BMAP_LARGE_LOW + 1];
156 	__u64 ptrs[NILFS_BMAP_LARGE_LOW + 1];
157 	int ret, n;
158 
159 	if (bmap->b_ops->bop_check_delete != NULL) {
160 		ret = bmap->b_ops->bop_check_delete(bmap, key);
161 		if (ret > 0) {
162 			n = bmap->b_ops->bop_gather_data(
163 				bmap, keys, ptrs, NILFS_BMAP_LARGE_LOW + 1);
164 			if (n < 0)
165 				return n;
166 			ret = nilfs_direct_delete_and_convert(
167 				bmap, key, keys, ptrs, n);
168 			if (ret == 0)
169 				bmap->b_u.u_flags &= ~NILFS_BMAP_LARGE;
170 
171 			return ret;
172 		} else if (ret < 0)
173 			return ret;
174 	}
175 
176 	return bmap->b_ops->bop_delete(bmap, key);
177 }
178 
179 /**
180  * nilfs_bmap_seek_key - seek a valid entry and return its key
181  * @bmap: bmap struct
182  * @start: start key number
183  * @keyp: place to store valid key
184  *
185  * Description: nilfs_bmap_seek_key() seeks a valid key on @bmap
186  * starting from @start, and stores it to @keyp if found.
187  *
188  * Return Value: On success, 0 is returned. On error, one of the following
189  * negative error codes is returned.
190  *
191  * %-EIO - I/O error.
192  *
193  * %-ENOMEM - Insufficient amount of memory available.
194  *
195  * %-ENOENT - No valid entry was found
196  */
nilfs_bmap_seek_key(struct nilfs_bmap * bmap,__u64 start,__u64 * keyp)197 int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp)
198 {
199 	int ret;
200 
201 	down_read(&bmap->b_sem);
202 	ret = bmap->b_ops->bop_seek_key(bmap, start, keyp);
203 	up_read(&bmap->b_sem);
204 
205 	if (ret < 0)
206 		ret = nilfs_bmap_convert_error(bmap, __func__, ret);
207 	return ret;
208 }
209 
nilfs_bmap_last_key(struct nilfs_bmap * bmap,__u64 * keyp)210 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp)
211 {
212 	int ret;
213 
214 	down_read(&bmap->b_sem);
215 	ret = bmap->b_ops->bop_last_key(bmap, keyp);
216 	up_read(&bmap->b_sem);
217 
218 	if (ret < 0)
219 		ret = nilfs_bmap_convert_error(bmap, __func__, ret);
220 	return ret;
221 }
222 
223 /**
224  * nilfs_bmap_delete - delete a key-record pair from a bmap
225  * @bmap: bmap
226  * @key: key
227  *
228  * Description: nilfs_bmap_delete() deletes the key-record pair specified by
229  * @key from @bmap.
230  *
231  * Return Value: On success, 0 is returned. On error, one of the following
232  * negative error codes is returned.
233  *
234  * %-EIO - I/O error.
235  *
236  * %-ENOMEM - Insufficient amount of memory available.
237  *
238  * %-ENOENT - A record associated with @key does not exist.
239  */
nilfs_bmap_delete(struct nilfs_bmap * bmap,__u64 key)240 int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key)
241 {
242 	int ret;
243 
244 	down_write(&bmap->b_sem);
245 	ret = nilfs_bmap_do_delete(bmap, key);
246 	up_write(&bmap->b_sem);
247 
248 	return nilfs_bmap_convert_error(bmap, __func__, ret);
249 }
250 
nilfs_bmap_do_truncate(struct nilfs_bmap * bmap,__u64 key)251 static int nilfs_bmap_do_truncate(struct nilfs_bmap *bmap, __u64 key)
252 {
253 	__u64 lastkey;
254 	int ret;
255 
256 	ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
257 	if (ret < 0) {
258 		if (ret == -ENOENT)
259 			ret = 0;
260 		return ret;
261 	}
262 
263 	while (key <= lastkey) {
264 		ret = nilfs_bmap_do_delete(bmap, lastkey);
265 		if (ret < 0)
266 			return ret;
267 		ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
268 		if (ret < 0) {
269 			if (ret == -ENOENT)
270 				ret = 0;
271 			return ret;
272 		}
273 	}
274 	return 0;
275 }
276 
277 /**
278  * nilfs_bmap_truncate - truncate a bmap to a specified key
279  * @bmap: bmap
280  * @key: key
281  *
282  * Description: nilfs_bmap_truncate() removes key-record pairs whose keys are
283  * greater than or equal to @key from @bmap.
284  *
285  * Return Value: On success, 0 is returned. On error, one of the following
286  * negative error codes is returned.
287  *
288  * %-EIO - I/O error.
289  *
290  * %-ENOMEM - Insufficient amount of memory available.
291  */
nilfs_bmap_truncate(struct nilfs_bmap * bmap,__u64 key)292 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key)
293 {
294 	int ret;
295 
296 	down_write(&bmap->b_sem);
297 	ret = nilfs_bmap_do_truncate(bmap, key);
298 	up_write(&bmap->b_sem);
299 
300 	return nilfs_bmap_convert_error(bmap, __func__, ret);
301 }
302 
303 /**
304  * nilfs_bmap_clear - free resources a bmap holds
305  * @bmap: bmap
306  *
307  * Description: nilfs_bmap_clear() frees resources associated with @bmap.
308  */
nilfs_bmap_clear(struct nilfs_bmap * bmap)309 void nilfs_bmap_clear(struct nilfs_bmap *bmap)
310 {
311 	down_write(&bmap->b_sem);
312 	if (bmap->b_ops->bop_clear != NULL)
313 		bmap->b_ops->bop_clear(bmap);
314 	up_write(&bmap->b_sem);
315 }
316 
317 /**
318  * nilfs_bmap_propagate - propagate dirty state
319  * @bmap: bmap
320  * @bh: buffer head
321  *
322  * Description: nilfs_bmap_propagate() marks the buffers that directly or
323  * indirectly refer to the block specified by @bh dirty.
324  *
325  * Return Value: On success, 0 is returned. On error, one of the following
326  * negative error codes is returned.
327  *
328  * %-EIO - I/O error.
329  *
330  * %-ENOMEM - Insufficient amount of memory available.
331  */
nilfs_bmap_propagate(struct nilfs_bmap * bmap,struct buffer_head * bh)332 int nilfs_bmap_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh)
333 {
334 	int ret;
335 
336 	down_write(&bmap->b_sem);
337 	ret = bmap->b_ops->bop_propagate(bmap, bh);
338 	up_write(&bmap->b_sem);
339 
340 	return nilfs_bmap_convert_error(bmap, __func__, ret);
341 }
342 
343 /**
344  * nilfs_bmap_lookup_dirty_buffers -
345  * @bmap: bmap
346  * @listp: pointer to buffer head list
347  */
nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap * bmap,struct list_head * listp)348 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *bmap,
349 				     struct list_head *listp)
350 {
351 	if (bmap->b_ops->bop_lookup_dirty_buffers != NULL)
352 		bmap->b_ops->bop_lookup_dirty_buffers(bmap, listp);
353 }
354 
355 /**
356  * nilfs_bmap_assign - assign a new block number to a block
357  * @bmap: bmap
358  * @bh: pointer to buffer head
359  * @blocknr: block number
360  * @binfo: block information
361  *
362  * Description: nilfs_bmap_assign() assigns the block number @blocknr to the
363  * buffer specified by @bh.
364  *
365  * Return Value: On success, 0 is returned and the buffer head of a newly
366  * create buffer and the block information associated with the buffer are
367  * stored in the place pointed by @bh and @binfo, respectively. On error, one
368  * of the following negative error codes is returned.
369  *
370  * %-EIO - I/O error.
371  *
372  * %-ENOMEM - Insufficient amount of memory available.
373  */
nilfs_bmap_assign(struct nilfs_bmap * bmap,struct buffer_head ** bh,unsigned long blocknr,union nilfs_binfo * binfo)374 int nilfs_bmap_assign(struct nilfs_bmap *bmap,
375 		      struct buffer_head **bh,
376 		      unsigned long blocknr,
377 		      union nilfs_binfo *binfo)
378 {
379 	int ret;
380 
381 	down_write(&bmap->b_sem);
382 	ret = bmap->b_ops->bop_assign(bmap, bh, blocknr, binfo);
383 	up_write(&bmap->b_sem);
384 
385 	return nilfs_bmap_convert_error(bmap, __func__, ret);
386 }
387 
388 /**
389  * nilfs_bmap_mark - mark block dirty
390  * @bmap: bmap
391  * @key: key
392  * @level: level
393  *
394  * Description: nilfs_bmap_mark() marks the block specified by @key and @level
395  * as dirty.
396  *
397  * Return Value: On success, 0 is returned. On error, one of the following
398  * negative error codes is returned.
399  *
400  * %-EIO - I/O error.
401  *
402  * %-ENOMEM - Insufficient amount of memory available.
403  */
nilfs_bmap_mark(struct nilfs_bmap * bmap,__u64 key,int level)404 int nilfs_bmap_mark(struct nilfs_bmap *bmap, __u64 key, int level)
405 {
406 	int ret;
407 
408 	if (bmap->b_ops->bop_mark == NULL)
409 		return 0;
410 
411 	down_write(&bmap->b_sem);
412 	ret = bmap->b_ops->bop_mark(bmap, key, level);
413 	up_write(&bmap->b_sem);
414 
415 	return nilfs_bmap_convert_error(bmap, __func__, ret);
416 }
417 
418 /**
419  * nilfs_bmap_test_and_clear_dirty - test and clear a bmap dirty state
420  * @bmap: bmap
421  *
422  * Description: nilfs_test_and_clear() is the atomic operation to test and
423  * clear the dirty state of @bmap.
424  *
425  * Return Value: 1 is returned if @bmap is dirty, or 0 if clear.
426  */
nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap * bmap)427 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *bmap)
428 {
429 	int ret;
430 
431 	down_write(&bmap->b_sem);
432 	ret = nilfs_bmap_dirty(bmap);
433 	nilfs_bmap_clear_dirty(bmap);
434 	up_write(&bmap->b_sem);
435 	return ret;
436 }
437 
438 
439 /*
440  * Internal use only
441  */
nilfs_bmap_data_get_key(const struct nilfs_bmap * bmap,const struct buffer_head * bh)442 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap,
443 			      const struct buffer_head *bh)
444 {
445 	struct buffer_head *pbh;
446 	__u64 key;
447 
448 	key = page_index(bh->b_page) << (PAGE_SHIFT -
449 					 bmap->b_inode->i_blkbits);
450 	for (pbh = page_buffers(bh->b_page); pbh != bh; pbh = pbh->b_this_page)
451 		key++;
452 
453 	return key;
454 }
455 
nilfs_bmap_find_target_seq(const struct nilfs_bmap * bmap,__u64 key)456 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key)
457 {
458 	__s64 diff;
459 
460 	diff = key - bmap->b_last_allocated_key;
461 	if ((nilfs_bmap_keydiff_abs(diff) < NILFS_INODE_BMAP_SIZE) &&
462 	    (bmap->b_last_allocated_ptr != NILFS_BMAP_INVALID_PTR) &&
463 	    (bmap->b_last_allocated_ptr + diff > 0))
464 		return bmap->b_last_allocated_ptr + diff;
465 	else
466 		return NILFS_BMAP_INVALID_PTR;
467 }
468 
469 #define NILFS_BMAP_GROUP_DIV	8
nilfs_bmap_find_target_in_group(const struct nilfs_bmap * bmap)470 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap)
471 {
472 	struct inode *dat = nilfs_bmap_get_dat(bmap);
473 	unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat);
474 	unsigned long group = bmap->b_inode->i_ino / entries_per_group;
475 
476 	return group * entries_per_group +
477 		(bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) *
478 		(entries_per_group / NILFS_BMAP_GROUP_DIV);
479 }
480 
481 static struct lock_class_key nilfs_bmap_dat_lock_key;
482 static struct lock_class_key nilfs_bmap_mdt_lock_key;
483 
484 /**
485  * nilfs_bmap_read - read a bmap from an inode
486  * @bmap: bmap
487  * @raw_inode: on-disk inode
488  *
489  * Description: nilfs_bmap_read() initializes the bmap @bmap.
490  *
491  * Return Value: On success, 0 is returned. On error, the following negative
492  * error code is returned.
493  *
494  * %-ENOMEM - Insufficient amount of memory available.
495  */
nilfs_bmap_read(struct nilfs_bmap * bmap,struct nilfs_inode * raw_inode)496 int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
497 {
498 	if (raw_inode == NULL)
499 		memset(bmap->b_u.u_data, 0, NILFS_BMAP_SIZE);
500 	else
501 		memcpy(bmap->b_u.u_data, raw_inode->i_bmap, NILFS_BMAP_SIZE);
502 
503 	init_rwsem(&bmap->b_sem);
504 	bmap->b_state = 0;
505 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
506 	switch (bmap->b_inode->i_ino) {
507 	case NILFS_DAT_INO:
508 		bmap->b_ptr_type = NILFS_BMAP_PTR_P;
509 		bmap->b_last_allocated_key = 0;
510 		bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
511 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
512 		break;
513 	case NILFS_CPFILE_INO:
514 	case NILFS_SUFILE_INO:
515 		bmap->b_ptr_type = NILFS_BMAP_PTR_VS;
516 		bmap->b_last_allocated_key = 0;
517 		bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
518 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
519 		break;
520 	case NILFS_IFILE_INO:
521 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
522 		fallthrough;
523 	default:
524 		bmap->b_ptr_type = NILFS_BMAP_PTR_VM;
525 		bmap->b_last_allocated_key = 0;
526 		bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
527 		break;
528 	}
529 
530 	return (bmap->b_u.u_flags & NILFS_BMAP_LARGE) ?
531 		nilfs_btree_init(bmap) : nilfs_direct_init(bmap);
532 }
533 
534 /**
535  * nilfs_bmap_write - write back a bmap to an inode
536  * @bmap: bmap
537  * @raw_inode: on-disk inode
538  *
539  * Description: nilfs_bmap_write() stores @bmap in @raw_inode.
540  */
nilfs_bmap_write(struct nilfs_bmap * bmap,struct nilfs_inode * raw_inode)541 void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
542 {
543 	down_write(&bmap->b_sem);
544 	memcpy(raw_inode->i_bmap, bmap->b_u.u_data,
545 	       NILFS_INODE_BMAP_SIZE * sizeof(__le64));
546 	if (bmap->b_inode->i_ino == NILFS_DAT_INO)
547 		bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
548 
549 	up_write(&bmap->b_sem);
550 }
551 
nilfs_bmap_init_gc(struct nilfs_bmap * bmap)552 void nilfs_bmap_init_gc(struct nilfs_bmap *bmap)
553 {
554 	memset(&bmap->b_u, 0, NILFS_BMAP_SIZE);
555 	init_rwsem(&bmap->b_sem);
556 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
557 	bmap->b_ptr_type = NILFS_BMAP_PTR_U;
558 	bmap->b_last_allocated_key = 0;
559 	bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
560 	bmap->b_state = 0;
561 	nilfs_btree_init_gc(bmap);
562 }
563 
nilfs_bmap_save(const struct nilfs_bmap * bmap,struct nilfs_bmap_store * store)564 void nilfs_bmap_save(const struct nilfs_bmap *bmap,
565 		     struct nilfs_bmap_store *store)
566 {
567 	memcpy(store->data, bmap->b_u.u_data, sizeof(store->data));
568 	store->last_allocated_key = bmap->b_last_allocated_key;
569 	store->last_allocated_ptr = bmap->b_last_allocated_ptr;
570 	store->state = bmap->b_state;
571 }
572 
nilfs_bmap_restore(struct nilfs_bmap * bmap,const struct nilfs_bmap_store * store)573 void nilfs_bmap_restore(struct nilfs_bmap *bmap,
574 			const struct nilfs_bmap_store *store)
575 {
576 	memcpy(bmap->b_u.u_data, store->data, sizeof(store->data));
577 	bmap->b_last_allocated_key = store->last_allocated_key;
578 	bmap->b_last_allocated_ptr = store->last_allocated_ptr;
579 	bmap->b_state = store->state;
580 }
581