1 /*
2  * bmap.c - NILFS block mapping.
3  *
4  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  *
20  * Written by Koji Sato <koji@osrg.net>.
21  */
22 
23 #include <linux/fs.h>
24 #include <linux/string.h>
25 #include <linux/errno.h>
26 #include "nilfs.h"
27 #include "bmap.h"
28 #include "btree.h"
29 #include "direct.h"
30 #include "btnode.h"
31 #include "mdt.h"
32 #include "dat.h"
33 #include "alloc.h"
34 
nilfs_bmap_get_dat(const struct nilfs_bmap * bmap)35 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap)
36 {
37 	struct the_nilfs *nilfs = bmap->b_inode->i_sb->s_fs_info;
38 
39 	return nilfs->ns_dat;
40 }
41 
nilfs_bmap_convert_error(struct nilfs_bmap * bmap,const char * fname,int err)42 static int nilfs_bmap_convert_error(struct nilfs_bmap *bmap,
43 				     const char *fname, int err)
44 {
45 	struct inode *inode = bmap->b_inode;
46 
47 	if (err == -EINVAL) {
48 		nilfs_error(inode->i_sb, fname,
49 			    "broken bmap (inode number=%lu)\n", inode->i_ino);
50 		err = -EIO;
51 	}
52 	return err;
53 }
54 
55 /**
56  * nilfs_bmap_lookup_at_level - find a data block or node block
57  * @bmap: bmap
58  * @key: key
59  * @level: level
60  * @ptrp: place to store the value associated to @key
61  *
62  * Description: nilfs_bmap_lookup_at_level() finds a record whose key
63  * matches @key in the block at @level of the bmap.
64  *
65  * Return Value: On success, 0 is returned and the record associated with @key
66  * is stored in the place pointed by @ptrp. On error, one of the following
67  * negative error codes is returned.
68  *
69  * %-EIO - I/O error.
70  *
71  * %-ENOMEM - Insufficient amount of memory available.
72  *
73  * %-ENOENT - A record associated with @key does not exist.
74  */
nilfs_bmap_lookup_at_level(struct nilfs_bmap * bmap,__u64 key,int level,__u64 * ptrp)75 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *bmap, __u64 key, int level,
76 			       __u64 *ptrp)
77 {
78 	sector_t blocknr;
79 	int ret;
80 
81 	down_read(&bmap->b_sem);
82 	ret = bmap->b_ops->bop_lookup(bmap, key, level, ptrp);
83 	if (ret < 0) {
84 		ret = nilfs_bmap_convert_error(bmap, __func__, ret);
85 		goto out;
86 	}
87 	if (NILFS_BMAP_USE_VBN(bmap)) {
88 		ret = nilfs_dat_translate(nilfs_bmap_get_dat(bmap), *ptrp,
89 					  &blocknr);
90 		if (!ret)
91 			*ptrp = blocknr;
92 	}
93 
94  out:
95 	up_read(&bmap->b_sem);
96 	return ret;
97 }
98 
nilfs_bmap_lookup_contig(struct nilfs_bmap * bmap,__u64 key,__u64 * ptrp,unsigned maxblocks)99 int nilfs_bmap_lookup_contig(struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp,
100 			     unsigned maxblocks)
101 {
102 	int ret;
103 
104 	down_read(&bmap->b_sem);
105 	ret = bmap->b_ops->bop_lookup_contig(bmap, key, ptrp, maxblocks);
106 	up_read(&bmap->b_sem);
107 
108 	return nilfs_bmap_convert_error(bmap, __func__, ret);
109 }
110 
nilfs_bmap_do_insert(struct nilfs_bmap * bmap,__u64 key,__u64 ptr)111 static int nilfs_bmap_do_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
112 {
113 	__u64 keys[NILFS_BMAP_SMALL_HIGH + 1];
114 	__u64 ptrs[NILFS_BMAP_SMALL_HIGH + 1];
115 	int ret, n;
116 
117 	if (bmap->b_ops->bop_check_insert != NULL) {
118 		ret = bmap->b_ops->bop_check_insert(bmap, key);
119 		if (ret > 0) {
120 			n = bmap->b_ops->bop_gather_data(
121 				bmap, keys, ptrs, NILFS_BMAP_SMALL_HIGH + 1);
122 			if (n < 0)
123 				return n;
124 			ret = nilfs_btree_convert_and_insert(
125 				bmap, key, ptr, keys, ptrs, n);
126 			if (ret == 0)
127 				bmap->b_u.u_flags |= NILFS_BMAP_LARGE;
128 
129 			return ret;
130 		} else if (ret < 0)
131 			return ret;
132 	}
133 
134 	return bmap->b_ops->bop_insert(bmap, key, ptr);
135 }
136 
137 /**
138  * nilfs_bmap_insert - insert a new key-record pair into a bmap
139  * @bmap: bmap
140  * @key: key
141  * @rec: record
142  *
143  * Description: nilfs_bmap_insert() inserts the new key-record pair specified
144  * by @key and @rec into @bmap.
145  *
146  * Return Value: On success, 0 is returned. On error, one of the following
147  * negative error codes is returned.
148  *
149  * %-EIO - I/O error.
150  *
151  * %-ENOMEM - Insufficient amount of memory available.
152  *
153  * %-EEXIST - A record associated with @key already exist.
154  */
nilfs_bmap_insert(struct nilfs_bmap * bmap,unsigned long key,unsigned long rec)155 int nilfs_bmap_insert(struct nilfs_bmap *bmap,
156 		      unsigned long key,
157 		      unsigned long rec)
158 {
159 	int ret;
160 
161 	down_write(&bmap->b_sem);
162 	ret = nilfs_bmap_do_insert(bmap, key, rec);
163 	up_write(&bmap->b_sem);
164 
165 	return nilfs_bmap_convert_error(bmap, __func__, ret);
166 }
167 
nilfs_bmap_do_delete(struct nilfs_bmap * bmap,__u64 key)168 static int nilfs_bmap_do_delete(struct nilfs_bmap *bmap, __u64 key)
169 {
170 	__u64 keys[NILFS_BMAP_LARGE_LOW + 1];
171 	__u64 ptrs[NILFS_BMAP_LARGE_LOW + 1];
172 	int ret, n;
173 
174 	if (bmap->b_ops->bop_check_delete != NULL) {
175 		ret = bmap->b_ops->bop_check_delete(bmap, key);
176 		if (ret > 0) {
177 			n = bmap->b_ops->bop_gather_data(
178 				bmap, keys, ptrs, NILFS_BMAP_LARGE_LOW + 1);
179 			if (n < 0)
180 				return n;
181 			ret = nilfs_direct_delete_and_convert(
182 				bmap, key, keys, ptrs, n);
183 			if (ret == 0)
184 				bmap->b_u.u_flags &= ~NILFS_BMAP_LARGE;
185 
186 			return ret;
187 		} else if (ret < 0)
188 			return ret;
189 	}
190 
191 	return bmap->b_ops->bop_delete(bmap, key);
192 }
193 
nilfs_bmap_last_key(struct nilfs_bmap * bmap,unsigned long * key)194 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, unsigned long *key)
195 {
196 	__u64 lastkey;
197 	int ret;
198 
199 	down_read(&bmap->b_sem);
200 	ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
201 	up_read(&bmap->b_sem);
202 
203 	if (ret < 0)
204 		ret = nilfs_bmap_convert_error(bmap, __func__, ret);
205 	else
206 		*key = lastkey;
207 	return ret;
208 }
209 
210 /**
211  * nilfs_bmap_delete - delete a key-record pair from a bmap
212  * @bmap: bmap
213  * @key: key
214  *
215  * Description: nilfs_bmap_delete() deletes the key-record pair specified by
216  * @key from @bmap.
217  *
218  * Return Value: On success, 0 is returned. On error, one of the following
219  * negative error codes is returned.
220  *
221  * %-EIO - I/O error.
222  *
223  * %-ENOMEM - Insufficient amount of memory available.
224  *
225  * %-ENOENT - A record associated with @key does not exist.
226  */
nilfs_bmap_delete(struct nilfs_bmap * bmap,unsigned long key)227 int nilfs_bmap_delete(struct nilfs_bmap *bmap, unsigned long key)
228 {
229 	int ret;
230 
231 	down_write(&bmap->b_sem);
232 	ret = nilfs_bmap_do_delete(bmap, key);
233 	up_write(&bmap->b_sem);
234 
235 	return nilfs_bmap_convert_error(bmap, __func__, ret);
236 }
237 
nilfs_bmap_do_truncate(struct nilfs_bmap * bmap,unsigned long key)238 static int nilfs_bmap_do_truncate(struct nilfs_bmap *bmap, unsigned long key)
239 {
240 	__u64 lastkey;
241 	int ret;
242 
243 	ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
244 	if (ret < 0) {
245 		if (ret == -ENOENT)
246 			ret = 0;
247 		return ret;
248 	}
249 
250 	while (key <= lastkey) {
251 		ret = nilfs_bmap_do_delete(bmap, lastkey);
252 		if (ret < 0)
253 			return ret;
254 		ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
255 		if (ret < 0) {
256 			if (ret == -ENOENT)
257 				ret = 0;
258 			return ret;
259 		}
260 	}
261 	return 0;
262 }
263 
264 /**
265  * nilfs_bmap_truncate - truncate a bmap to a specified key
266  * @bmap: bmap
267  * @key: key
268  *
269  * Description: nilfs_bmap_truncate() removes key-record pairs whose keys are
270  * greater than or equal to @key from @bmap.
271  *
272  * Return Value: On success, 0 is returned. On error, one of the following
273  * negative error codes is returned.
274  *
275  * %-EIO - I/O error.
276  *
277  * %-ENOMEM - Insufficient amount of memory available.
278  */
nilfs_bmap_truncate(struct nilfs_bmap * bmap,unsigned long key)279 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, unsigned long key)
280 {
281 	int ret;
282 
283 	down_write(&bmap->b_sem);
284 	ret = nilfs_bmap_do_truncate(bmap, key);
285 	up_write(&bmap->b_sem);
286 
287 	return nilfs_bmap_convert_error(bmap, __func__, ret);
288 }
289 
290 /**
291  * nilfs_bmap_clear - free resources a bmap holds
292  * @bmap: bmap
293  *
294  * Description: nilfs_bmap_clear() frees resources associated with @bmap.
295  */
nilfs_bmap_clear(struct nilfs_bmap * bmap)296 void nilfs_bmap_clear(struct nilfs_bmap *bmap)
297 {
298 	down_write(&bmap->b_sem);
299 	if (bmap->b_ops->bop_clear != NULL)
300 		bmap->b_ops->bop_clear(bmap);
301 	up_write(&bmap->b_sem);
302 }
303 
304 /**
305  * nilfs_bmap_propagate - propagate dirty state
306  * @bmap: bmap
307  * @bh: buffer head
308  *
309  * Description: nilfs_bmap_propagate() marks the buffers that directly or
310  * indirectly refer to the block specified by @bh dirty.
311  *
312  * Return Value: On success, 0 is returned. On error, one of the following
313  * negative error codes is returned.
314  *
315  * %-EIO - I/O error.
316  *
317  * %-ENOMEM - Insufficient amount of memory available.
318  */
nilfs_bmap_propagate(struct nilfs_bmap * bmap,struct buffer_head * bh)319 int nilfs_bmap_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh)
320 {
321 	int ret;
322 
323 	down_write(&bmap->b_sem);
324 	ret = bmap->b_ops->bop_propagate(bmap, bh);
325 	up_write(&bmap->b_sem);
326 
327 	return nilfs_bmap_convert_error(bmap, __func__, ret);
328 }
329 
330 /**
331  * nilfs_bmap_lookup_dirty_buffers -
332  * @bmap: bmap
333  * @listp: pointer to buffer head list
334  */
nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap * bmap,struct list_head * listp)335 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *bmap,
336 				     struct list_head *listp)
337 {
338 	if (bmap->b_ops->bop_lookup_dirty_buffers != NULL)
339 		bmap->b_ops->bop_lookup_dirty_buffers(bmap, listp);
340 }
341 
342 /**
343  * nilfs_bmap_assign - assign a new block number to a block
344  * @bmap: bmap
345  * @bhp: pointer to buffer head
346  * @blocknr: block number
347  * @binfo: block information
348  *
349  * Description: nilfs_bmap_assign() assigns the block number @blocknr to the
350  * buffer specified by @bh.
351  *
352  * Return Value: On success, 0 is returned and the buffer head of a newly
353  * create buffer and the block information associated with the buffer are
354  * stored in the place pointed by @bh and @binfo, respectively. On error, one
355  * of the following negative error codes is returned.
356  *
357  * %-EIO - I/O error.
358  *
359  * %-ENOMEM - Insufficient amount of memory available.
360  */
nilfs_bmap_assign(struct nilfs_bmap * bmap,struct buffer_head ** bh,unsigned long blocknr,union nilfs_binfo * binfo)361 int nilfs_bmap_assign(struct nilfs_bmap *bmap,
362 		      struct buffer_head **bh,
363 		      unsigned long blocknr,
364 		      union nilfs_binfo *binfo)
365 {
366 	int ret;
367 
368 	down_write(&bmap->b_sem);
369 	ret = bmap->b_ops->bop_assign(bmap, bh, blocknr, binfo);
370 	up_write(&bmap->b_sem);
371 
372 	return nilfs_bmap_convert_error(bmap, __func__, ret);
373 }
374 
375 /**
376  * nilfs_bmap_mark - mark block dirty
377  * @bmap: bmap
378  * @key: key
379  * @level: level
380  *
381  * Description: nilfs_bmap_mark() marks the block specified by @key and @level
382  * as dirty.
383  *
384  * Return Value: On success, 0 is returned. On error, one of the following
385  * negative error codes is returned.
386  *
387  * %-EIO - I/O error.
388  *
389  * %-ENOMEM - Insufficient amount of memory available.
390  */
nilfs_bmap_mark(struct nilfs_bmap * bmap,__u64 key,int level)391 int nilfs_bmap_mark(struct nilfs_bmap *bmap, __u64 key, int level)
392 {
393 	int ret;
394 
395 	if (bmap->b_ops->bop_mark == NULL)
396 		return 0;
397 
398 	down_write(&bmap->b_sem);
399 	ret = bmap->b_ops->bop_mark(bmap, key, level);
400 	up_write(&bmap->b_sem);
401 
402 	return nilfs_bmap_convert_error(bmap, __func__, ret);
403 }
404 
405 /**
406  * nilfs_bmap_test_and_clear_dirty - test and clear a bmap dirty state
407  * @bmap: bmap
408  *
409  * Description: nilfs_test_and_clear() is the atomic operation to test and
410  * clear the dirty state of @bmap.
411  *
412  * Return Value: 1 is returned if @bmap is dirty, or 0 if clear.
413  */
nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap * bmap)414 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *bmap)
415 {
416 	int ret;
417 
418 	down_write(&bmap->b_sem);
419 	ret = nilfs_bmap_dirty(bmap);
420 	nilfs_bmap_clear_dirty(bmap);
421 	up_write(&bmap->b_sem);
422 	return ret;
423 }
424 
425 
426 /*
427  * Internal use only
428  */
nilfs_bmap_data_get_key(const struct nilfs_bmap * bmap,const struct buffer_head * bh)429 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap,
430 			      const struct buffer_head *bh)
431 {
432 	struct buffer_head *pbh;
433 	__u64 key;
434 
435 	key = page_index(bh->b_page) << (PAGE_CACHE_SHIFT -
436 					 bmap->b_inode->i_blkbits);
437 	for (pbh = page_buffers(bh->b_page); pbh != bh; pbh = pbh->b_this_page)
438 		key++;
439 
440 	return key;
441 }
442 
nilfs_bmap_find_target_seq(const struct nilfs_bmap * bmap,__u64 key)443 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key)
444 {
445 	__s64 diff;
446 
447 	diff = key - bmap->b_last_allocated_key;
448 	if ((nilfs_bmap_keydiff_abs(diff) < NILFS_INODE_BMAP_SIZE) &&
449 	    (bmap->b_last_allocated_ptr != NILFS_BMAP_INVALID_PTR) &&
450 	    (bmap->b_last_allocated_ptr + diff > 0))
451 		return bmap->b_last_allocated_ptr + diff;
452 	else
453 		return NILFS_BMAP_INVALID_PTR;
454 }
455 
456 #define NILFS_BMAP_GROUP_DIV	8
nilfs_bmap_find_target_in_group(const struct nilfs_bmap * bmap)457 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap)
458 {
459 	struct inode *dat = nilfs_bmap_get_dat(bmap);
460 	unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat);
461 	unsigned long group = bmap->b_inode->i_ino / entries_per_group;
462 
463 	return group * entries_per_group +
464 		(bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) *
465 		(entries_per_group / NILFS_BMAP_GROUP_DIV);
466 }
467 
468 static struct lock_class_key nilfs_bmap_dat_lock_key;
469 static struct lock_class_key nilfs_bmap_mdt_lock_key;
470 
471 /**
472  * nilfs_bmap_read - read a bmap from an inode
473  * @bmap: bmap
474  * @raw_inode: on-disk inode
475  *
476  * Description: nilfs_bmap_read() initializes the bmap @bmap.
477  *
478  * Return Value: On success, 0 is returned. On error, the following negative
479  * error code is returned.
480  *
481  * %-ENOMEM - Insufficient amount of memory available.
482  */
nilfs_bmap_read(struct nilfs_bmap * bmap,struct nilfs_inode * raw_inode)483 int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
484 {
485 	if (raw_inode == NULL)
486 		memset(bmap->b_u.u_data, 0, NILFS_BMAP_SIZE);
487 	else
488 		memcpy(bmap->b_u.u_data, raw_inode->i_bmap, NILFS_BMAP_SIZE);
489 
490 	init_rwsem(&bmap->b_sem);
491 	bmap->b_state = 0;
492 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
493 	switch (bmap->b_inode->i_ino) {
494 	case NILFS_DAT_INO:
495 		bmap->b_ptr_type = NILFS_BMAP_PTR_P;
496 		bmap->b_last_allocated_key = 0;
497 		bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
498 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
499 		break;
500 	case NILFS_CPFILE_INO:
501 	case NILFS_SUFILE_INO:
502 		bmap->b_ptr_type = NILFS_BMAP_PTR_VS;
503 		bmap->b_last_allocated_key = 0;
504 		bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
505 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
506 		break;
507 	case NILFS_IFILE_INO:
508 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
509 		/* Fall through */
510 	default:
511 		bmap->b_ptr_type = NILFS_BMAP_PTR_VM;
512 		bmap->b_last_allocated_key = 0;
513 		bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
514 		break;
515 	}
516 
517 	return (bmap->b_u.u_flags & NILFS_BMAP_LARGE) ?
518 		nilfs_btree_init(bmap) : nilfs_direct_init(bmap);
519 }
520 
521 /**
522  * nilfs_bmap_write - write back a bmap to an inode
523  * @bmap: bmap
524  * @raw_inode: on-disk inode
525  *
526  * Description: nilfs_bmap_write() stores @bmap in @raw_inode.
527  */
nilfs_bmap_write(struct nilfs_bmap * bmap,struct nilfs_inode * raw_inode)528 void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
529 {
530 	down_write(&bmap->b_sem);
531 	memcpy(raw_inode->i_bmap, bmap->b_u.u_data,
532 	       NILFS_INODE_BMAP_SIZE * sizeof(__le64));
533 	if (bmap->b_inode->i_ino == NILFS_DAT_INO)
534 		bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
535 
536 	up_write(&bmap->b_sem);
537 }
538 
nilfs_bmap_init_gc(struct nilfs_bmap * bmap)539 void nilfs_bmap_init_gc(struct nilfs_bmap *bmap)
540 {
541 	memset(&bmap->b_u, 0, NILFS_BMAP_SIZE);
542 	init_rwsem(&bmap->b_sem);
543 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
544 	bmap->b_ptr_type = NILFS_BMAP_PTR_U;
545 	bmap->b_last_allocated_key = 0;
546 	bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
547 	bmap->b_state = 0;
548 	nilfs_btree_init_gc(bmap);
549 }
550 
nilfs_bmap_save(const struct nilfs_bmap * bmap,struct nilfs_bmap_store * store)551 void nilfs_bmap_save(const struct nilfs_bmap *bmap,
552 		     struct nilfs_bmap_store *store)
553 {
554 	memcpy(store->data, bmap->b_u.u_data, sizeof(store->data));
555 	store->last_allocated_key = bmap->b_last_allocated_key;
556 	store->last_allocated_ptr = bmap->b_last_allocated_ptr;
557 	store->state = bmap->b_state;
558 }
559 
nilfs_bmap_restore(struct nilfs_bmap * bmap,const struct nilfs_bmap_store * store)560 void nilfs_bmap_restore(struct nilfs_bmap *bmap,
561 			const struct nilfs_bmap_store *store)
562 {
563 	memcpy(bmap->b_u.u_data, store->data, sizeof(store->data));
564 	bmap->b_last_allocated_key = store->last_allocated_key;
565 	bmap->b_last_allocated_ptr = store->last_allocated_ptr;
566 	bmap->b_state = store->state;
567 }
568