Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/hpfs/map.c | |
3 | * | |
4 | * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 | |
5 | * | |
6 | * mapping structures to memory with some minimal checks | |
7 | */ | |
8 | ||
9 | #include "hpfs_fn.h" | |
10 | ||
11 | unsigned *hpfs_map_dnode_bitmap(struct super_block *s, struct quad_buffer_head *qbh) | |
12 | { | |
13 | return hpfs_map_4sectors(s, hpfs_sb(s)->sb_dmap, qbh, 0); | |
14 | } | |
15 | ||
16 | unsigned int *hpfs_map_bitmap(struct super_block *s, unsigned bmp_block, | |
17 | struct quad_buffer_head *qbh, char *id) | |
18 | { | |
19 | secno sec; | |
20 | if (hpfs_sb(s)->sb_chk) if (bmp_block * 16384 > hpfs_sb(s)->sb_fs_size) { | |
21 | hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x at %s", bmp_block, id); | |
22 | return NULL; | |
23 | } | |
0b69760b | 24 | sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]); |
1da177e4 LT |
25 | if (!sec || sec > hpfs_sb(s)->sb_fs_size-4) { |
26 | hpfs_error(s, "invalid bitmap block pointer %08x -> %08x at %s", bmp_block, sec, id); | |
27 | return NULL; | |
28 | } | |
29 | return hpfs_map_4sectors(s, sec, qbh, 4); | |
30 | } | |
31 | ||
32 | /* | |
33 | * Load first code page into kernel memory, return pointer to 256-byte array, | |
34 | * first 128 bytes are uppercasing table for chars 128-255, next 128 bytes are | |
35 | * lowercasing table | |
36 | */ | |
37 | ||
7e7742ee | 38 | unsigned char *hpfs_load_code_page(struct super_block *s, secno cps) |
1da177e4 LT |
39 | { |
40 | struct buffer_head *bh; | |
41 | secno cpds; | |
42 | unsigned cpi; | |
43 | unsigned char *ptr; | |
44 | unsigned char *cp_table; | |
45 | int i; | |
46 | struct code_page_data *cpd; | |
47 | struct code_page_directory *cp = hpfs_map_sector(s, cps, &bh, 0); | |
48 | if (!cp) return NULL; | |
0b69760b MP |
49 | if (le32_to_cpu(cp->magic) != CP_DIR_MAGIC) { |
50 | printk("HPFS: Code page directory magic doesn't match (magic = %08x)\n", le32_to_cpu(cp->magic)); | |
1da177e4 LT |
51 | brelse(bh); |
52 | return NULL; | |
53 | } | |
0b69760b | 54 | if (!le32_to_cpu(cp->n_code_pages)) { |
1da177e4 LT |
55 | printk("HPFS: n_code_pages == 0\n"); |
56 | brelse(bh); | |
57 | return NULL; | |
58 | } | |
0b69760b MP |
59 | cpds = le32_to_cpu(cp->array[0].code_page_data); |
60 | cpi = le16_to_cpu(cp->array[0].index); | |
1da177e4 LT |
61 | brelse(bh); |
62 | ||
63 | if (cpi >= 3) { | |
64 | printk("HPFS: Code page index out of array\n"); | |
65 | return NULL; | |
66 | } | |
67 | ||
68 | if (!(cpd = hpfs_map_sector(s, cpds, &bh, 0))) return NULL; | |
0b69760b | 69 | if (le16_to_cpu(cpd->offs[cpi]) > 0x178) { |
1da177e4 LT |
70 | printk("HPFS: Code page index out of sector\n"); |
71 | brelse(bh); | |
72 | return NULL; | |
73 | } | |
0b69760b | 74 | ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6; |
1da177e4 LT |
75 | if (!(cp_table = kmalloc(256, GFP_KERNEL))) { |
76 | printk("HPFS: out of memory for code page table\n"); | |
77 | brelse(bh); | |
78 | return NULL; | |
79 | } | |
80 | memcpy(cp_table, ptr, 128); | |
81 | brelse(bh); | |
82 | ||
83 | /* Try to build lowercasing table from uppercasing one */ | |
84 | ||
85 | for (i=128; i<256; i++) cp_table[i]=i; | |
86 | for (i=128; i<256; i++) if (cp_table[i-128]!=i && cp_table[i-128]>=128) | |
87 | cp_table[cp_table[i-128]] = i; | |
88 | ||
89 | return cp_table; | |
90 | } | |
91 | ||
92 | secno *hpfs_load_bitmap_directory(struct super_block *s, secno bmp) | |
93 | { | |
94 | struct buffer_head *bh; | |
95 | int n = (hpfs_sb(s)->sb_fs_size + 0x200000 - 1) >> 21; | |
96 | int i; | |
97 | secno *b; | |
98 | if (!(b = kmalloc(n * 512, GFP_KERNEL))) { | |
99 | printk("HPFS: can't allocate memory for bitmap directory\n"); | |
100 | return NULL; | |
101 | } | |
102 | for (i=0;i<n;i++) { | |
103 | secno *d = hpfs_map_sector(s, bmp+i, &bh, n - i - 1); | |
104 | if (!d) { | |
105 | kfree(b); | |
106 | return NULL; | |
107 | } | |
108 | memcpy((char *)b + 512 * i, d, 512); | |
109 | brelse(bh); | |
110 | } | |
111 | return b; | |
112 | } | |
113 | ||
114 | /* | |
115 | * Load fnode to memory | |
116 | */ | |
117 | ||
118 | struct fnode *hpfs_map_fnode(struct super_block *s, ino_t ino, struct buffer_head **bhp) | |
119 | { | |
120 | struct fnode *fnode; | |
121 | if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ino, 1, "fnode")) { | |
122 | return NULL; | |
123 | } | |
124 | if ((fnode = hpfs_map_sector(s, ino, bhp, FNODE_RD_AHEAD))) { | |
125 | if (hpfs_sb(s)->sb_chk) { | |
126 | struct extended_attribute *ea; | |
127 | struct extended_attribute *ea_end; | |
0b69760b | 128 | if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) { |
18debbbc RD |
129 | hpfs_error(s, "bad magic on fnode %08lx", |
130 | (unsigned long)ino); | |
1da177e4 LT |
131 | goto bail; |
132 | } | |
133 | if (!fnode->dirflag) { | |
134 | if ((unsigned)fnode->btree.n_used_nodes + (unsigned)fnode->btree.n_free_nodes != | |
135 | (fnode->btree.internal ? 12 : 8)) { | |
18debbbc RD |
136 | hpfs_error(s, |
137 | "bad number of nodes in fnode %08lx", | |
138 | (unsigned long)ino); | |
1da177e4 LT |
139 | goto bail; |
140 | } | |
0b69760b | 141 | if (le16_to_cpu(fnode->btree.first_free) != |
1da177e4 | 142 | 8 + fnode->btree.n_used_nodes * (fnode->btree.internal ? 8 : 12)) { |
18debbbc RD |
143 | hpfs_error(s, |
144 | "bad first_free pointer in fnode %08lx", | |
145 | (unsigned long)ino); | |
1da177e4 LT |
146 | goto bail; |
147 | } | |
148 | } | |
0b69760b MP |
149 | if (le16_to_cpu(fnode->ea_size_s) && (le16_to_cpu(fnode->ea_offs) < 0xc4 || |
150 | le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200)) { | |
18debbbc RD |
151 | hpfs_error(s, |
152 | "bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x", | |
153 | (unsigned long)ino, | |
0b69760b | 154 | le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s)); |
1da177e4 LT |
155 | goto bail; |
156 | } | |
157 | ea = fnode_ea(fnode); | |
158 | ea_end = fnode_end_ea(fnode); | |
159 | while (ea != ea_end) { | |
160 | if (ea > ea_end) { | |
18debbbc RD |
161 | hpfs_error(s, "bad EA in fnode %08lx", |
162 | (unsigned long)ino); | |
1da177e4 LT |
163 | goto bail; |
164 | } | |
165 | ea = next_ea(ea); | |
166 | } | |
167 | } | |
168 | } | |
169 | return fnode; | |
170 | bail: | |
171 | brelse(*bhp); | |
172 | return NULL; | |
173 | } | |
174 | ||
175 | struct anode *hpfs_map_anode(struct super_block *s, anode_secno ano, struct buffer_head **bhp) | |
176 | { | |
177 | struct anode *anode; | |
178 | if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ano, 1, "anode")) return NULL; | |
179 | if ((anode = hpfs_map_sector(s, ano, bhp, ANODE_RD_AHEAD))) | |
180 | if (hpfs_sb(s)->sb_chk) { | |
0b69760b | 181 | if (le32_to_cpu(anode->magic) != ANODE_MAGIC) { |
1da177e4 LT |
182 | hpfs_error(s, "bad magic on anode %08x", ano); |
183 | goto bail; | |
184 | } | |
0b69760b MP |
185 | if (le32_to_cpu(anode->self) != ano) { |
186 | hpfs_error(s, "self pointer invalid on anode %08x", ano); | |
187 | goto bail; | |
188 | } | |
1da177e4 LT |
189 | if ((unsigned)anode->btree.n_used_nodes + (unsigned)anode->btree.n_free_nodes != |
190 | (anode->btree.internal ? 60 : 40)) { | |
191 | hpfs_error(s, "bad number of nodes in anode %08x", ano); | |
192 | goto bail; | |
193 | } | |
0b69760b | 194 | if (le16_to_cpu(anode->btree.first_free) != |
1da177e4 LT |
195 | 8 + anode->btree.n_used_nodes * (anode->btree.internal ? 8 : 12)) { |
196 | hpfs_error(s, "bad first_free pointer in anode %08x", ano); | |
197 | goto bail; | |
198 | } | |
199 | } | |
200 | return anode; | |
201 | bail: | |
202 | brelse(*bhp); | |
203 | return NULL; | |
204 | } | |
205 | ||
206 | /* | |
207 | * Load dnode to memory and do some checks | |
208 | */ | |
209 | ||
210 | struct dnode *hpfs_map_dnode(struct super_block *s, unsigned secno, | |
211 | struct quad_buffer_head *qbh) | |
212 | { | |
213 | struct dnode *dnode; | |
214 | if (hpfs_sb(s)->sb_chk) { | |
215 | if (hpfs_chk_sectors(s, secno, 4, "dnode")) return NULL; | |
216 | if (secno & 3) { | |
217 | hpfs_error(s, "dnode %08x not byte-aligned", secno); | |
218 | return NULL; | |
219 | } | |
220 | } | |
221 | if ((dnode = hpfs_map_4sectors(s, secno, qbh, DNODE_RD_AHEAD))) | |
222 | if (hpfs_sb(s)->sb_chk) { | |
223 | unsigned p, pp = 0; | |
7e7742ee | 224 | unsigned char *d = (unsigned char *)dnode; |
1da177e4 | 225 | int b = 0; |
0b69760b | 226 | if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) { |
1da177e4 LT |
227 | hpfs_error(s, "bad magic on dnode %08x", secno); |
228 | goto bail; | |
229 | } | |
0b69760b MP |
230 | if (le32_to_cpu(dnode->self) != secno) |
231 | hpfs_error(s, "bad self pointer on dnode %08x self = %08x", secno, le32_to_cpu(dnode->self)); | |
1da177e4 LT |
232 | /* Check dirents - bad dirents would cause infinite |
233 | loops or shooting to memory */ | |
0b69760b MP |
234 | if (le32_to_cpu(dnode->first_free) > 2048) { |
235 | hpfs_error(s, "dnode %08x has first_free == %08x", secno, le32_to_cpu(dnode->first_free)); | |
1da177e4 LT |
236 | goto bail; |
237 | } | |
0b69760b | 238 | for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) { |
1da177e4 | 239 | struct hpfs_dirent *de = (struct hpfs_dirent *)((char *)dnode + p); |
0b69760b | 240 | if (le16_to_cpu(de->length) > 292 || (le16_to_cpu(de->length) < 32) || (le16_to_cpu(de->length) & 3) || p + le16_to_cpu(de->length) > 2048) { |
1da177e4 LT |
241 | hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp); |
242 | goto bail; | |
243 | } | |
0b69760b MP |
244 | if (((31 + de->namelen + de->down*4 + 3) & ~3) != le16_to_cpu(de->length)) { |
245 | if (((31 + de->namelen + de->down*4 + 3) & ~3) < le16_to_cpu(de->length) && s->s_flags & MS_RDONLY) goto ok; | |
1da177e4 LT |
246 | hpfs_error(s, "namelen does not match dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp); |
247 | goto bail; | |
248 | } | |
249 | ok: | |
250 | if (hpfs_sb(s)->sb_chk >= 2) b |= 1 << de->down; | |
251 | if (de->down) if (de_down_pointer(de) < 0x10) { | |
252 | hpfs_error(s, "bad down pointer in dnode %08x, dirent %03x, last %03x", secno, p, pp); | |
253 | goto bail; | |
254 | } | |
255 | pp = p; | |
256 | ||
257 | } | |
0b69760b | 258 | if (p != le32_to_cpu(dnode->first_free)) { |
1da177e4 LT |
259 | hpfs_error(s, "size on last dirent does not match first_free; dnode %08x", secno); |
260 | goto bail; | |
261 | } | |
262 | if (d[pp + 30] != 1 || d[pp + 31] != 255) { | |
263 | hpfs_error(s, "dnode %08x does not end with \\377 entry", secno); | |
264 | goto bail; | |
265 | } | |
266 | if (b == 3) printk("HPFS: warning: unbalanced dnode tree, dnode %08x; see hpfs.txt 4 more info\n", secno); | |
267 | } | |
268 | return dnode; | |
269 | bail: | |
270 | hpfs_brelse4(qbh); | |
271 | return NULL; | |
272 | } | |
273 | ||
274 | dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino) | |
275 | { | |
276 | struct buffer_head *bh; | |
277 | struct fnode *fnode; | |
278 | dnode_secno dno; | |
279 | ||
280 | fnode = hpfs_map_fnode(s, ino, &bh); | |
281 | if (!fnode) | |
282 | return 0; | |
283 | ||
0b69760b | 284 | dno = le32_to_cpu(fnode->u.external[0].disk_secno); |
1da177e4 LT |
285 | brelse(bh); |
286 | return dno; | |
287 | } |