1 /*
2 * direct.c - NILFS direct block pointer.
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 * Written by Koji Sato.
17 */
18
19 #include <linux/errno.h>
20 #include "nilfs.h"
21 #include "page.h"
22 #include "direct.h"
23 #include "alloc.h"
24 #include "dat.h"
25
nilfs_direct_dptrs(const struct nilfs_bmap * direct)26 static inline __le64 *nilfs_direct_dptrs(const struct nilfs_bmap *direct)
27 {
28 return (__le64 *)
29 ((struct nilfs_direct_node *)direct->b_u.u_data + 1);
30 }
31
32 static inline __u64
nilfs_direct_get_ptr(const struct nilfs_bmap * direct,__u64 key)33 nilfs_direct_get_ptr(const struct nilfs_bmap *direct, __u64 key)
34 {
35 return le64_to_cpu(*(nilfs_direct_dptrs(direct) + key));
36 }
37
nilfs_direct_set_ptr(struct nilfs_bmap * direct,__u64 key,__u64 ptr)38 static inline void nilfs_direct_set_ptr(struct nilfs_bmap *direct,
39 __u64 key, __u64 ptr)
40 {
41 *(nilfs_direct_dptrs(direct) + key) = cpu_to_le64(ptr);
42 }
43
nilfs_direct_lookup(const struct nilfs_bmap * direct,__u64 key,int level,__u64 * ptrp)44 static int nilfs_direct_lookup(const struct nilfs_bmap *direct,
45 __u64 key, int level, __u64 *ptrp)
46 {
47 __u64 ptr;
48
49 if (key > NILFS_DIRECT_KEY_MAX || level != 1)
50 return -ENOENT;
51 ptr = nilfs_direct_get_ptr(direct, key);
52 if (ptr == NILFS_BMAP_INVALID_PTR)
53 return -ENOENT;
54
55 *ptrp = ptr;
56 return 0;
57 }
58
nilfs_direct_lookup_contig(const struct nilfs_bmap * direct,__u64 key,__u64 * ptrp,unsigned int maxblocks)59 static int nilfs_direct_lookup_contig(const struct nilfs_bmap *direct,
60 __u64 key, __u64 *ptrp,
61 unsigned int maxblocks)
62 {
63 struct inode *dat = NULL;
64 __u64 ptr, ptr2;
65 sector_t blocknr;
66 int ret, cnt;
67
68 if (key > NILFS_DIRECT_KEY_MAX)
69 return -ENOENT;
70 ptr = nilfs_direct_get_ptr(direct, key);
71 if (ptr == NILFS_BMAP_INVALID_PTR)
72 return -ENOENT;
73
74 if (NILFS_BMAP_USE_VBN(direct)) {
75 dat = nilfs_bmap_get_dat(direct);
76 ret = nilfs_dat_translate(dat, ptr, &blocknr);
77 if (ret < 0)
78 return ret;
79 ptr = blocknr;
80 }
81
82 maxblocks = min_t(unsigned int, maxblocks,
83 NILFS_DIRECT_KEY_MAX - key + 1);
84 for (cnt = 1; cnt < maxblocks &&
85 (ptr2 = nilfs_direct_get_ptr(direct, key + cnt)) !=
86 NILFS_BMAP_INVALID_PTR;
87 cnt++) {
88 if (dat) {
89 ret = nilfs_dat_translate(dat, ptr2, &blocknr);
90 if (ret < 0)
91 return ret;
92 ptr2 = blocknr;
93 }
94 if (ptr2 != ptr + cnt)
95 break;
96 }
97 *ptrp = ptr;
98 return cnt;
99 }
100
101 static __u64
nilfs_direct_find_target_v(const struct nilfs_bmap * direct,__u64 key)102 nilfs_direct_find_target_v(const struct nilfs_bmap *direct, __u64 key)
103 {
104 __u64 ptr;
105
106 ptr = nilfs_bmap_find_target_seq(direct, key);
107 if (ptr != NILFS_BMAP_INVALID_PTR)
108 /* sequential access */
109 return ptr;
110
111 /* block group */
112 return nilfs_bmap_find_target_in_group(direct);
113 }
114
nilfs_direct_insert(struct nilfs_bmap * bmap,__u64 key,__u64 ptr)115 static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
116 {
117 union nilfs_bmap_ptr_req req;
118 struct inode *dat = NULL;
119 struct buffer_head *bh;
120 int ret;
121
122 if (key > NILFS_DIRECT_KEY_MAX)
123 return -ENOENT;
124 if (nilfs_direct_get_ptr(bmap, key) != NILFS_BMAP_INVALID_PTR)
125 return -EEXIST;
126
127 if (NILFS_BMAP_USE_VBN(bmap)) {
128 req.bpr_ptr = nilfs_direct_find_target_v(bmap, key);
129 dat = nilfs_bmap_get_dat(bmap);
130 }
131 ret = nilfs_bmap_prepare_alloc_ptr(bmap, &req, dat);
132 if (!ret) {
133 /* ptr must be a pointer to a buffer head. */
134 bh = (struct buffer_head *)((unsigned long)ptr);
135 set_buffer_nilfs_volatile(bh);
136
137 nilfs_bmap_commit_alloc_ptr(bmap, &req, dat);
138 nilfs_direct_set_ptr(bmap, key, req.bpr_ptr);
139
140 if (!nilfs_bmap_dirty(bmap))
141 nilfs_bmap_set_dirty(bmap);
142
143 if (NILFS_BMAP_USE_VBN(bmap))
144 nilfs_bmap_set_target_v(bmap, key, req.bpr_ptr);
145
146 nilfs_inode_add_blocks(bmap->b_inode, 1);
147 }
148 return ret;
149 }
150
nilfs_direct_delete(struct nilfs_bmap * bmap,__u64 key)151 static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key)
152 {
153 union nilfs_bmap_ptr_req req;
154 struct inode *dat;
155 int ret;
156
157 if (key > NILFS_DIRECT_KEY_MAX ||
158 nilfs_direct_get_ptr(bmap, key) == NILFS_BMAP_INVALID_PTR)
159 return -ENOENT;
160
161 dat = NILFS_BMAP_USE_VBN(bmap) ? nilfs_bmap_get_dat(bmap) : NULL;
162 req.bpr_ptr = nilfs_direct_get_ptr(bmap, key);
163
164 ret = nilfs_bmap_prepare_end_ptr(bmap, &req, dat);
165 if (!ret) {
166 nilfs_bmap_commit_end_ptr(bmap, &req, dat);
167 nilfs_direct_set_ptr(bmap, key, NILFS_BMAP_INVALID_PTR);
168 nilfs_inode_sub_blocks(bmap->b_inode, 1);
169 }
170 return ret;
171 }
172
nilfs_direct_seek_key(const struct nilfs_bmap * direct,__u64 start,__u64 * keyp)173 static int nilfs_direct_seek_key(const struct nilfs_bmap *direct, __u64 start,
174 __u64 *keyp)
175 {
176 __u64 key;
177
178 for (key = start; key <= NILFS_DIRECT_KEY_MAX; key++) {
179 if (nilfs_direct_get_ptr(direct, key) !=
180 NILFS_BMAP_INVALID_PTR) {
181 *keyp = key;
182 return 0;
183 }
184 }
185 return -ENOENT;
186 }
187
nilfs_direct_last_key(const struct nilfs_bmap * direct,__u64 * keyp)188 static int nilfs_direct_last_key(const struct nilfs_bmap *direct, __u64 *keyp)
189 {
190 __u64 key, lastkey;
191
192 lastkey = NILFS_DIRECT_KEY_MAX + 1;
193 for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++)
194 if (nilfs_direct_get_ptr(direct, key) !=
195 NILFS_BMAP_INVALID_PTR)
196 lastkey = key;
197
198 if (lastkey == NILFS_DIRECT_KEY_MAX + 1)
199 return -ENOENT;
200
201 *keyp = lastkey;
202
203 return 0;
204 }
205
nilfs_direct_check_insert(const struct nilfs_bmap * bmap,__u64 key)206 static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key)
207 {
208 return key > NILFS_DIRECT_KEY_MAX;
209 }
210
nilfs_direct_gather_data(struct nilfs_bmap * direct,__u64 * keys,__u64 * ptrs,int nitems)211 static int nilfs_direct_gather_data(struct nilfs_bmap *direct,
212 __u64 *keys, __u64 *ptrs, int nitems)
213 {
214 __u64 key;
215 __u64 ptr;
216 int n;
217
218 if (nitems > NILFS_DIRECT_NBLOCKS)
219 nitems = NILFS_DIRECT_NBLOCKS;
220 n = 0;
221 for (key = 0; key < nitems; key++) {
222 ptr = nilfs_direct_get_ptr(direct, key);
223 if (ptr != NILFS_BMAP_INVALID_PTR) {
224 keys[n] = key;
225 ptrs[n] = ptr;
226 n++;
227 }
228 }
229 return n;
230 }
231
nilfs_direct_delete_and_convert(struct nilfs_bmap * bmap,__u64 key,__u64 * keys,__u64 * ptrs,int n)232 int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap,
233 __u64 key, __u64 *keys, __u64 *ptrs, int n)
234 {
235 __le64 *dptrs;
236 int ret, i, j;
237
238 /* no need to allocate any resource for conversion */
239
240 /* delete */
241 ret = bmap->b_ops->bop_delete(bmap, key);
242 if (ret < 0)
243 return ret;
244
245 /* free resources */
246 if (bmap->b_ops->bop_clear != NULL)
247 bmap->b_ops->bop_clear(bmap);
248
249 /* convert */
250 dptrs = nilfs_direct_dptrs(bmap);
251 for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) {
252 if ((j < n) && (i == keys[j])) {
253 dptrs[i] = (i != key) ?
254 cpu_to_le64(ptrs[j]) :
255 NILFS_BMAP_INVALID_PTR;
256 j++;
257 } else
258 dptrs[i] = NILFS_BMAP_INVALID_PTR;
259 }
260
261 nilfs_direct_init(bmap);
262 return 0;
263 }
264
nilfs_direct_propagate(struct nilfs_bmap * bmap,struct buffer_head * bh)265 static int nilfs_direct_propagate(struct nilfs_bmap *bmap,
266 struct buffer_head *bh)
267 {
268 struct nilfs_palloc_req oldreq, newreq;
269 struct inode *dat;
270 __u64 key;
271 __u64 ptr;
272 int ret;
273
274 if (!NILFS_BMAP_USE_VBN(bmap))
275 return 0;
276
277 dat = nilfs_bmap_get_dat(bmap);
278 key = nilfs_bmap_data_get_key(bmap, bh);
279 ptr = nilfs_direct_get_ptr(bmap, key);
280 if (!buffer_nilfs_volatile(bh)) {
281 oldreq.pr_entry_nr = ptr;
282 newreq.pr_entry_nr = ptr;
283 ret = nilfs_dat_prepare_update(dat, &oldreq, &newreq);
284 if (ret < 0)
285 return ret;
286 nilfs_dat_commit_update(dat, &oldreq, &newreq,
287 bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
288 set_buffer_nilfs_volatile(bh);
289 nilfs_direct_set_ptr(bmap, key, newreq.pr_entry_nr);
290 } else
291 ret = nilfs_dat_mark_dirty(dat, ptr);
292
293 return ret;
294 }
295
nilfs_direct_assign_v(struct nilfs_bmap * direct,__u64 key,__u64 ptr,struct buffer_head ** bh,sector_t blocknr,union nilfs_binfo * binfo)296 static int nilfs_direct_assign_v(struct nilfs_bmap *direct,
297 __u64 key, __u64 ptr,
298 struct buffer_head **bh,
299 sector_t blocknr,
300 union nilfs_binfo *binfo)
301 {
302 struct inode *dat = nilfs_bmap_get_dat(direct);
303 union nilfs_bmap_ptr_req req;
304 int ret;
305
306 req.bpr_ptr = ptr;
307 ret = nilfs_dat_prepare_start(dat, &req.bpr_req);
308 if (!ret) {
309 nilfs_dat_commit_start(dat, &req.bpr_req, blocknr);
310 binfo->bi_v.bi_vblocknr = cpu_to_le64(ptr);
311 binfo->bi_v.bi_blkoff = cpu_to_le64(key);
312 }
313 return ret;
314 }
315
nilfs_direct_assign_p(struct nilfs_bmap * direct,__u64 key,__u64 ptr,struct buffer_head ** bh,sector_t blocknr,union nilfs_binfo * binfo)316 static int nilfs_direct_assign_p(struct nilfs_bmap *direct,
317 __u64 key, __u64 ptr,
318 struct buffer_head **bh,
319 sector_t blocknr,
320 union nilfs_binfo *binfo)
321 {
322 nilfs_direct_set_ptr(direct, key, blocknr);
323
324 binfo->bi_dat.bi_blkoff = cpu_to_le64(key);
325 binfo->bi_dat.bi_level = 0;
326
327 return 0;
328 }
329
nilfs_direct_assign(struct nilfs_bmap * bmap,struct buffer_head ** bh,sector_t blocknr,union nilfs_binfo * binfo)330 static int nilfs_direct_assign(struct nilfs_bmap *bmap,
331 struct buffer_head **bh,
332 sector_t blocknr,
333 union nilfs_binfo *binfo)
334 {
335 __u64 key;
336 __u64 ptr;
337
338 key = nilfs_bmap_data_get_key(bmap, *bh);
339 if (unlikely(key > NILFS_DIRECT_KEY_MAX)) {
340 nilfs_msg(bmap->b_inode->i_sb, KERN_CRIT,
341 "%s (ino=%lu): invalid key: %llu", __func__,
342 bmap->b_inode->i_ino, (unsigned long long)key);
343 return -EINVAL;
344 }
345 ptr = nilfs_direct_get_ptr(bmap, key);
346 if (unlikely(ptr == NILFS_BMAP_INVALID_PTR)) {
347 nilfs_msg(bmap->b_inode->i_sb, KERN_CRIT,
348 "%s (ino=%lu): invalid pointer: %llu", __func__,
349 bmap->b_inode->i_ino, (unsigned long long)ptr);
350 return -EINVAL;
351 }
352
353 return NILFS_BMAP_USE_VBN(bmap) ?
354 nilfs_direct_assign_v(bmap, key, ptr, bh, blocknr, binfo) :
355 nilfs_direct_assign_p(bmap, key, ptr, bh, blocknr, binfo);
356 }
357
358 static const struct nilfs_bmap_operations nilfs_direct_ops = {
359 .bop_lookup = nilfs_direct_lookup,
360 .bop_lookup_contig = nilfs_direct_lookup_contig,
361 .bop_insert = nilfs_direct_insert,
362 .bop_delete = nilfs_direct_delete,
363 .bop_clear = NULL,
364
365 .bop_propagate = nilfs_direct_propagate,
366
367 .bop_lookup_dirty_buffers = NULL,
368
369 .bop_assign = nilfs_direct_assign,
370 .bop_mark = NULL,
371
372 .bop_seek_key = nilfs_direct_seek_key,
373 .bop_last_key = nilfs_direct_last_key,
374
375 .bop_check_insert = nilfs_direct_check_insert,
376 .bop_check_delete = NULL,
377 .bop_gather_data = nilfs_direct_gather_data,
378 };
379
380
nilfs_direct_init(struct nilfs_bmap * bmap)381 int nilfs_direct_init(struct nilfs_bmap *bmap)
382 {
383 bmap->b_ops = &nilfs_direct_ops;
384 return 0;
385 }
386