1 /*
2 * linux/fs/adfs/dir_fplus.c
3 *
4 * Copyright (C) 1997-1999 Russell King
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 version 2 as
8 * published by the Free Software Foundation.
9 */
10 #include <linux/buffer_head.h>
11 #include <linux/slab.h>
12 #include "adfs.h"
13 #include "dir_fplus.h"
14
15 static int
adfs_fplus_read(struct super_block * sb,unsigned int id,unsigned int sz,struct adfs_dir * dir)16 adfs_fplus_read(struct super_block *sb, unsigned int id, unsigned int sz, struct adfs_dir *dir)
17 {
18 struct adfs_bigdirheader *h;
19 struct adfs_bigdirtail *t;
20 unsigned long block;
21 unsigned int blk, size;
22 int i, ret = -EIO;
23
24 dir->nr_buffers = 0;
25
26 /* start off using fixed bh set - only alloc for big dirs */
27 dir->bh_fplus = &dir->bh[0];
28
29 block = __adfs_block_map(sb, id, 0);
30 if (!block) {
31 adfs_error(sb, "dir object %X has a hole at offset 0", id);
32 goto out;
33 }
34
35 dir->bh_fplus[0] = sb_bread(sb, block);
36 if (!dir->bh_fplus[0])
37 goto out;
38 dir->nr_buffers += 1;
39
40 h = (struct adfs_bigdirheader *)dir->bh_fplus[0]->b_data;
41 size = le32_to_cpu(h->bigdirsize);
42 if (size != sz) {
43 printk(KERN_WARNING "adfs: adfs_fplus_read:"
44 " directory header size %X\n"
45 " does not match directory size %X\n",
46 size, sz);
47 }
48
49 if (h->bigdirversion[0] != 0 || h->bigdirversion[1] != 0 ||
50 h->bigdirversion[2] != 0 || size & 2047 ||
51 h->bigdirstartname != cpu_to_le32(BIGDIRSTARTNAME)) {
52 printk(KERN_WARNING "adfs: dir object %X has"
53 " malformed dir header\n", id);
54 goto out;
55 }
56
57 size >>= sb->s_blocksize_bits;
58 if (size > ARRAY_SIZE(dir->bh)) {
59 /* this directory is too big for fixed bh set, must allocate */
60 struct buffer_head **bh_fplus =
61 kcalloc(size, sizeof(struct buffer_head *),
62 GFP_KERNEL);
63 if (!bh_fplus) {
64 adfs_error(sb, "not enough memory for"
65 " dir object %X (%d blocks)", id, size);
66 goto out;
67 }
68 dir->bh_fplus = bh_fplus;
69 /* copy over the pointer to the block that we've already read */
70 dir->bh_fplus[0] = dir->bh[0];
71 }
72
73 for (blk = 1; blk < size; blk++) {
74 block = __adfs_block_map(sb, id, blk);
75 if (!block) {
76 adfs_error(sb, "dir object %X has a hole at offset %d", id, blk);
77 goto out;
78 }
79
80 dir->bh_fplus[blk] = sb_bread(sb, block);
81 if (!dir->bh_fplus[blk]) {
82 adfs_error(sb, "dir object %x failed read for offset %d, mapped block %lX",
83 id, blk, block);
84 goto out;
85 }
86
87 dir->nr_buffers += 1;
88 }
89
90 t = (struct adfs_bigdirtail *)
91 (dir->bh_fplus[size - 1]->b_data + (sb->s_blocksize - 8));
92
93 if (t->bigdirendname != cpu_to_le32(BIGDIRENDNAME) ||
94 t->bigdirendmasseq != h->startmasseq ||
95 t->reserved[0] != 0 || t->reserved[1] != 0) {
96 printk(KERN_WARNING "adfs: dir object %X has "
97 "malformed dir end\n", id);
98 goto out;
99 }
100
101 dir->parent_id = le32_to_cpu(h->bigdirparent);
102 dir->sb = sb;
103 return 0;
104
105 out:
106 if (dir->bh_fplus) {
107 for (i = 0; i < dir->nr_buffers; i++)
108 brelse(dir->bh_fplus[i]);
109
110 if (&dir->bh[0] != dir->bh_fplus)
111 kfree(dir->bh_fplus);
112
113 dir->bh_fplus = NULL;
114 }
115
116 dir->nr_buffers = 0;
117 dir->sb = NULL;
118 return ret;
119 }
120
121 static int
adfs_fplus_setpos(struct adfs_dir * dir,unsigned int fpos)122 adfs_fplus_setpos(struct adfs_dir *dir, unsigned int fpos)
123 {
124 struct adfs_bigdirheader *h =
125 (struct adfs_bigdirheader *) dir->bh_fplus[0]->b_data;
126 int ret = -ENOENT;
127
128 if (fpos <= le32_to_cpu(h->bigdirentries)) {
129 dir->pos = fpos;
130 ret = 0;
131 }
132
133 return ret;
134 }
135
136 static void
dir_memcpy(struct adfs_dir * dir,unsigned int offset,void * to,int len)137 dir_memcpy(struct adfs_dir *dir, unsigned int offset, void *to, int len)
138 {
139 struct super_block *sb = dir->sb;
140 unsigned int buffer, partial, remainder;
141
142 buffer = offset >> sb->s_blocksize_bits;
143 offset &= sb->s_blocksize - 1;
144
145 partial = sb->s_blocksize - offset;
146
147 if (partial >= len)
148 memcpy(to, dir->bh_fplus[buffer]->b_data + offset, len);
149 else {
150 char *c = (char *)to;
151
152 remainder = len - partial;
153
154 memcpy(c,
155 dir->bh_fplus[buffer]->b_data + offset,
156 partial);
157
158 memcpy(c + partial,
159 dir->bh_fplus[buffer + 1]->b_data,
160 remainder);
161 }
162 }
163
164 static int
adfs_fplus_getnext(struct adfs_dir * dir,struct object_info * obj)165 adfs_fplus_getnext(struct adfs_dir *dir, struct object_info *obj)
166 {
167 struct adfs_bigdirheader *h =
168 (struct adfs_bigdirheader *) dir->bh_fplus[0]->b_data;
169 struct adfs_bigdirentry bde;
170 unsigned int offset;
171 int i, ret = -ENOENT;
172
173 if (dir->pos >= le32_to_cpu(h->bigdirentries))
174 goto out;
175
176 offset = offsetof(struct adfs_bigdirheader, bigdirname);
177 offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3);
178 offset += dir->pos * sizeof(struct adfs_bigdirentry);
179
180 dir_memcpy(dir, offset, &bde, sizeof(struct adfs_bigdirentry));
181
182 obj->loadaddr = le32_to_cpu(bde.bigdirload);
183 obj->execaddr = le32_to_cpu(bde.bigdirexec);
184 obj->size = le32_to_cpu(bde.bigdirlen);
185 obj->file_id = le32_to_cpu(bde.bigdirindaddr);
186 obj->attr = le32_to_cpu(bde.bigdirattr);
187 obj->name_len = le32_to_cpu(bde.bigdirobnamelen);
188
189 offset = offsetof(struct adfs_bigdirheader, bigdirname);
190 offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3);
191 offset += le32_to_cpu(h->bigdirentries) * sizeof(struct adfs_bigdirentry);
192 offset += le32_to_cpu(bde.bigdirobnameptr);
193
194 dir_memcpy(dir, offset, obj->name, obj->name_len);
195 for (i = 0; i < obj->name_len; i++)
196 if (obj->name[i] == '/')
197 obj->name[i] = '.';
198
199 obj->filetype = -1;
200
201 /*
202 * object is a file and is filetyped and timestamped?
203 * RISC OS 12-bit filetype is stored in load_address[19:8]
204 */
205 if ((0 == (obj->attr & ADFS_NDA_DIRECTORY)) &&
206 (0xfff00000 == (0xfff00000 & obj->loadaddr))) {
207 obj->filetype = (__u16) ((0x000fff00 & obj->loadaddr) >> 8);
208
209 /* optionally append the ,xyz hex filetype suffix */
210 if (ADFS_SB(dir->sb)->s_ftsuffix)
211 obj->name_len +=
212 append_filetype_suffix(
213 &obj->name[obj->name_len],
214 obj->filetype);
215 }
216
217 dir->pos += 1;
218 ret = 0;
219 out:
220 return ret;
221 }
222
223 static int
adfs_fplus_sync(struct adfs_dir * dir)224 adfs_fplus_sync(struct adfs_dir *dir)
225 {
226 int err = 0;
227 int i;
228
229 for (i = dir->nr_buffers - 1; i >= 0; i--) {
230 struct buffer_head *bh = dir->bh_fplus[i];
231 sync_dirty_buffer(bh);
232 if (buffer_req(bh) && !buffer_uptodate(bh))
233 err = -EIO;
234 }
235
236 return err;
237 }
238
239 static void
adfs_fplus_free(struct adfs_dir * dir)240 adfs_fplus_free(struct adfs_dir *dir)
241 {
242 int i;
243
244 if (dir->bh_fplus) {
245 for (i = 0; i < dir->nr_buffers; i++)
246 brelse(dir->bh_fplus[i]);
247
248 if (&dir->bh[0] != dir->bh_fplus)
249 kfree(dir->bh_fplus);
250
251 dir->bh_fplus = NULL;
252 }
253
254 dir->nr_buffers = 0;
255 dir->sb = NULL;
256 }
257
258 struct adfs_dir_ops adfs_fplus_dir_ops = {
259 .read = adfs_fplus_read,
260 .setpos = adfs_fplus_setpos,
261 .getnext = adfs_fplus_getnext,
262 .sync = adfs_fplus_sync,
263 .free = adfs_fplus_free
264 };
265