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