xref: /linux/fs/nilfs2/direct.c (revision 8f8d5745bb520c76b81abef4a2cb3023d0313bfd)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * direct.c - NILFS direct block pointer.
4  *
5  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
6  *
7  * Written by Koji Sato.
8  */
9 
10 #include <linux/errno.h>
11 #include "nilfs.h"
12 #include "page.h"
13 #include "direct.h"
14 #include "alloc.h"
15 #include "dat.h"
16 
17 static inline __le64 *nilfs_direct_dptrs(const struct nilfs_bmap *direct)
18 {
19 	return (__le64 *)
20 		((struct nilfs_direct_node *)direct->b_u.u_data + 1);
21 }
22 
23 static inline __u64
24 nilfs_direct_get_ptr(const struct nilfs_bmap *direct, __u64 key)
25 {
26 	return le64_to_cpu(*(nilfs_direct_dptrs(direct) + key));
27 }
28 
29 static inline void nilfs_direct_set_ptr(struct nilfs_bmap *direct,
30 					__u64 key, __u64 ptr)
31 {
32 	*(nilfs_direct_dptrs(direct) + key) = cpu_to_le64(ptr);
33 }
34 
35 static int nilfs_direct_lookup(const struct nilfs_bmap *direct,
36 			       __u64 key, int level, __u64 *ptrp)
37 {
38 	__u64 ptr;
39 
40 	if (key > NILFS_DIRECT_KEY_MAX || level != 1)
41 		return -ENOENT;
42 	ptr = nilfs_direct_get_ptr(direct, key);
43 	if (ptr == NILFS_BMAP_INVALID_PTR)
44 		return -ENOENT;
45 
46 	*ptrp = ptr;
47 	return 0;
48 }
49 
50 static int nilfs_direct_lookup_contig(const struct nilfs_bmap *direct,
51 				      __u64 key, __u64 *ptrp,
52 				      unsigned int maxblocks)
53 {
54 	struct inode *dat = NULL;
55 	__u64 ptr, ptr2;
56 	sector_t blocknr;
57 	int ret, cnt;
58 
59 	if (key > NILFS_DIRECT_KEY_MAX)
60 		return -ENOENT;
61 	ptr = nilfs_direct_get_ptr(direct, key);
62 	if (ptr == NILFS_BMAP_INVALID_PTR)
63 		return -ENOENT;
64 
65 	if (NILFS_BMAP_USE_VBN(direct)) {
66 		dat = nilfs_bmap_get_dat(direct);
67 		ret = nilfs_dat_translate(dat, ptr, &blocknr);
68 		if (ret < 0)
69 			return ret;
70 		ptr = blocknr;
71 	}
72 
73 	maxblocks = min_t(unsigned int, maxblocks,
74 			  NILFS_DIRECT_KEY_MAX - key + 1);
75 	for (cnt = 1; cnt < maxblocks &&
76 		     (ptr2 = nilfs_direct_get_ptr(direct, key + cnt)) !=
77 		     NILFS_BMAP_INVALID_PTR;
78 	     cnt++) {
79 		if (dat) {
80 			ret = nilfs_dat_translate(dat, ptr2, &blocknr);
81 			if (ret < 0)
82 				return ret;
83 			ptr2 = blocknr;
84 		}
85 		if (ptr2 != ptr + cnt)
86 			break;
87 	}
88 	*ptrp = ptr;
89 	return cnt;
90 }
91 
92 static __u64
93 nilfs_direct_find_target_v(const struct nilfs_bmap *direct, __u64 key)
94 {
95 	__u64 ptr;
96 
97 	ptr = nilfs_bmap_find_target_seq(direct, key);
98 	if (ptr != NILFS_BMAP_INVALID_PTR)
99 		/* sequential access */
100 		return ptr;
101 
102 	/* block group */
103 	return nilfs_bmap_find_target_in_group(direct);
104 }
105 
106 static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
107 {
108 	union nilfs_bmap_ptr_req req;
109 	struct inode *dat = NULL;
110 	struct buffer_head *bh;
111 	int ret;
112 
113 	if (key > NILFS_DIRECT_KEY_MAX)
114 		return -ENOENT;
115 	if (nilfs_direct_get_ptr(bmap, key) != NILFS_BMAP_INVALID_PTR)
116 		return -EEXIST;
117 
118 	if (NILFS_BMAP_USE_VBN(bmap)) {
119 		req.bpr_ptr = nilfs_direct_find_target_v(bmap, key);
120 		dat = nilfs_bmap_get_dat(bmap);
121 	}
122 	ret = nilfs_bmap_prepare_alloc_ptr(bmap, &req, dat);
123 	if (!ret) {
124 		/* ptr must be a pointer to a buffer head. */
125 		bh = (struct buffer_head *)((unsigned long)ptr);
126 		set_buffer_nilfs_volatile(bh);
127 
128 		nilfs_bmap_commit_alloc_ptr(bmap, &req, dat);
129 		nilfs_direct_set_ptr(bmap, key, req.bpr_ptr);
130 
131 		if (!nilfs_bmap_dirty(bmap))
132 			nilfs_bmap_set_dirty(bmap);
133 
134 		if (NILFS_BMAP_USE_VBN(bmap))
135 			nilfs_bmap_set_target_v(bmap, key, req.bpr_ptr);
136 
137 		nilfs_inode_add_blocks(bmap->b_inode, 1);
138 	}
139 	return ret;
140 }
141 
142 static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key)
143 {
144 	union nilfs_bmap_ptr_req req;
145 	struct inode *dat;
146 	int ret;
147 
148 	if (key > NILFS_DIRECT_KEY_MAX ||
149 	    nilfs_direct_get_ptr(bmap, key) == NILFS_BMAP_INVALID_PTR)
150 		return -ENOENT;
151 
152 	dat = NILFS_BMAP_USE_VBN(bmap) ? nilfs_bmap_get_dat(bmap) : NULL;
153 	req.bpr_ptr = nilfs_direct_get_ptr(bmap, key);
154 
155 	ret = nilfs_bmap_prepare_end_ptr(bmap, &req, dat);
156 	if (!ret) {
157 		nilfs_bmap_commit_end_ptr(bmap, &req, dat);
158 		nilfs_direct_set_ptr(bmap, key, NILFS_BMAP_INVALID_PTR);
159 		nilfs_inode_sub_blocks(bmap->b_inode, 1);
160 	}
161 	return ret;
162 }
163 
164 static int nilfs_direct_seek_key(const struct nilfs_bmap *direct, __u64 start,
165 				 __u64 *keyp)
166 {
167 	__u64 key;
168 
169 	for (key = start; key <= NILFS_DIRECT_KEY_MAX; key++) {
170 		if (nilfs_direct_get_ptr(direct, key) !=
171 		    NILFS_BMAP_INVALID_PTR) {
172 			*keyp = key;
173 			return 0;
174 		}
175 	}
176 	return -ENOENT;
177 }
178 
179 static int nilfs_direct_last_key(const struct nilfs_bmap *direct, __u64 *keyp)
180 {
181 	__u64 key, lastkey;
182 
183 	lastkey = NILFS_DIRECT_KEY_MAX + 1;
184 	for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++)
185 		if (nilfs_direct_get_ptr(direct, key) !=
186 		    NILFS_BMAP_INVALID_PTR)
187 			lastkey = key;
188 
189 	if (lastkey == NILFS_DIRECT_KEY_MAX + 1)
190 		return -ENOENT;
191 
192 	*keyp = lastkey;
193 
194 	return 0;
195 }
196 
197 static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key)
198 {
199 	return key > NILFS_DIRECT_KEY_MAX;
200 }
201 
202 static int nilfs_direct_gather_data(struct nilfs_bmap *direct,
203 				    __u64 *keys, __u64 *ptrs, int nitems)
204 {
205 	__u64 key;
206 	__u64 ptr;
207 	int n;
208 
209 	if (nitems > NILFS_DIRECT_NBLOCKS)
210 		nitems = NILFS_DIRECT_NBLOCKS;
211 	n = 0;
212 	for (key = 0; key < nitems; key++) {
213 		ptr = nilfs_direct_get_ptr(direct, key);
214 		if (ptr != NILFS_BMAP_INVALID_PTR) {
215 			keys[n] = key;
216 			ptrs[n] = ptr;
217 			n++;
218 		}
219 	}
220 	return n;
221 }
222 
223 int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap,
224 				    __u64 key, __u64 *keys, __u64 *ptrs, int n)
225 {
226 	__le64 *dptrs;
227 	int ret, i, j;
228 
229 	/* no need to allocate any resource for conversion */
230 
231 	/* delete */
232 	ret = bmap->b_ops->bop_delete(bmap, key);
233 	if (ret < 0)
234 		return ret;
235 
236 	/* free resources */
237 	if (bmap->b_ops->bop_clear != NULL)
238 		bmap->b_ops->bop_clear(bmap);
239 
240 	/* convert */
241 	dptrs = nilfs_direct_dptrs(bmap);
242 	for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) {
243 		if ((j < n) && (i == keys[j])) {
244 			dptrs[i] = (i != key) ?
245 				cpu_to_le64(ptrs[j]) :
246 				NILFS_BMAP_INVALID_PTR;
247 			j++;
248 		} else
249 			dptrs[i] = NILFS_BMAP_INVALID_PTR;
250 	}
251 
252 	nilfs_direct_init(bmap);
253 	return 0;
254 }
255 
256 static int nilfs_direct_propagate(struct nilfs_bmap *bmap,
257 				  struct buffer_head *bh)
258 {
259 	struct nilfs_palloc_req oldreq, newreq;
260 	struct inode *dat;
261 	__u64 key;
262 	__u64 ptr;
263 	int ret;
264 
265 	if (!NILFS_BMAP_USE_VBN(bmap))
266 		return 0;
267 
268 	dat = nilfs_bmap_get_dat(bmap);
269 	key = nilfs_bmap_data_get_key(bmap, bh);
270 	ptr = nilfs_direct_get_ptr(bmap, key);
271 	if (!buffer_nilfs_volatile(bh)) {
272 		oldreq.pr_entry_nr = ptr;
273 		newreq.pr_entry_nr = ptr;
274 		ret = nilfs_dat_prepare_update(dat, &oldreq, &newreq);
275 		if (ret < 0)
276 			return ret;
277 		nilfs_dat_commit_update(dat, &oldreq, &newreq,
278 					bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
279 		set_buffer_nilfs_volatile(bh);
280 		nilfs_direct_set_ptr(bmap, key, newreq.pr_entry_nr);
281 	} else
282 		ret = nilfs_dat_mark_dirty(dat, ptr);
283 
284 	return ret;
285 }
286 
287 static int nilfs_direct_assign_v(struct nilfs_bmap *direct,
288 				 __u64 key, __u64 ptr,
289 				 struct buffer_head **bh,
290 				 sector_t blocknr,
291 				 union nilfs_binfo *binfo)
292 {
293 	struct inode *dat = nilfs_bmap_get_dat(direct);
294 	union nilfs_bmap_ptr_req req;
295 	int ret;
296 
297 	req.bpr_ptr = ptr;
298 	ret = nilfs_dat_prepare_start(dat, &req.bpr_req);
299 	if (!ret) {
300 		nilfs_dat_commit_start(dat, &req.bpr_req, blocknr);
301 		binfo->bi_v.bi_vblocknr = cpu_to_le64(ptr);
302 		binfo->bi_v.bi_blkoff = cpu_to_le64(key);
303 	}
304 	return ret;
305 }
306 
307 static int nilfs_direct_assign_p(struct nilfs_bmap *direct,
308 				 __u64 key, __u64 ptr,
309 				 struct buffer_head **bh,
310 				 sector_t blocknr,
311 				 union nilfs_binfo *binfo)
312 {
313 	nilfs_direct_set_ptr(direct, key, blocknr);
314 
315 	binfo->bi_dat.bi_blkoff = cpu_to_le64(key);
316 	binfo->bi_dat.bi_level = 0;
317 
318 	return 0;
319 }
320 
321 static int nilfs_direct_assign(struct nilfs_bmap *bmap,
322 			       struct buffer_head **bh,
323 			       sector_t blocknr,
324 			       union nilfs_binfo *binfo)
325 {
326 	__u64 key;
327 	__u64 ptr;
328 
329 	key = nilfs_bmap_data_get_key(bmap, *bh);
330 	if (unlikely(key > NILFS_DIRECT_KEY_MAX)) {
331 		nilfs_msg(bmap->b_inode->i_sb, KERN_CRIT,
332 			  "%s (ino=%lu): invalid key: %llu", __func__,
333 			  bmap->b_inode->i_ino, (unsigned long long)key);
334 		return -EINVAL;
335 	}
336 	ptr = nilfs_direct_get_ptr(bmap, key);
337 	if (unlikely(ptr == NILFS_BMAP_INVALID_PTR)) {
338 		nilfs_msg(bmap->b_inode->i_sb, KERN_CRIT,
339 			  "%s (ino=%lu): invalid pointer: %llu", __func__,
340 			  bmap->b_inode->i_ino, (unsigned long long)ptr);
341 		return -EINVAL;
342 	}
343 
344 	return NILFS_BMAP_USE_VBN(bmap) ?
345 		nilfs_direct_assign_v(bmap, key, ptr, bh, blocknr, binfo) :
346 		nilfs_direct_assign_p(bmap, key, ptr, bh, blocknr, binfo);
347 }
348 
349 static const struct nilfs_bmap_operations nilfs_direct_ops = {
350 	.bop_lookup		=	nilfs_direct_lookup,
351 	.bop_lookup_contig	=	nilfs_direct_lookup_contig,
352 	.bop_insert		=	nilfs_direct_insert,
353 	.bop_delete		=	nilfs_direct_delete,
354 	.bop_clear		=	NULL,
355 
356 	.bop_propagate		=	nilfs_direct_propagate,
357 
358 	.bop_lookup_dirty_buffers	=	NULL,
359 
360 	.bop_assign		=	nilfs_direct_assign,
361 	.bop_mark		=	NULL,
362 
363 	.bop_seek_key		=	nilfs_direct_seek_key,
364 	.bop_last_key		=	nilfs_direct_last_key,
365 
366 	.bop_check_insert	=	nilfs_direct_check_insert,
367 	.bop_check_delete	=	NULL,
368 	.bop_gather_data	=	nilfs_direct_gather_data,
369 };
370 
371 
372 int nilfs_direct_init(struct nilfs_bmap *bmap)
373 {
374 	bmap->b_ops = &nilfs_direct_ops;
375 	return 0;
376 }
377