blob: a790821366a7f045d068fe47df517dc479b0ecce [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
11unsigned *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
16unsigned 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 }
Mikulas Patocka0b697602011-05-08 20:44:26 +020024 sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 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
Al Viro7e7742e2010-01-31 17:09:29 -050038unsigned char *hpfs_load_code_page(struct super_block *s, secno cps)
Linus Torvalds1da177e2005-04-16 15:20:36 -070039{
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;
Mikulas Patocka0b697602011-05-08 20:44:26 +020049 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));
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 brelse(bh);
52 return NULL;
53 }
Mikulas Patocka0b697602011-05-08 20:44:26 +020054 if (!le32_to_cpu(cp->n_code_pages)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 printk("HPFS: n_code_pages == 0\n");
56 brelse(bh);
57 return NULL;
58 }
Mikulas Patocka0b697602011-05-08 20:44:26 +020059 cpds = le32_to_cpu(cp->array[0].code_page_data);
60 cpi = le16_to_cpu(cp->array[0].index);
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 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;
Mikulas Patocka0b697602011-05-08 20:44:26 +020069 if (le16_to_cpu(cpd->offs[cpi]) > 0x178) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 printk("HPFS: Code page index out of sector\n");
71 brelse(bh);
72 return NULL;
73 }
Mikulas Patocka0b697602011-05-08 20:44:26 +020074 ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6;
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 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
92secno *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
118struct 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;
Mikulas Patocka0b697602011-05-08 20:44:26 +0200128 if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) {
Randy Dunlap18debbb2006-12-06 20:37:05 -0800129 hpfs_error(s, "bad magic on fnode %08lx",
130 (unsigned long)ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 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)) {
Randy Dunlap18debbb2006-12-06 20:37:05 -0800136 hpfs_error(s,
137 "bad number of nodes in fnode %08lx",
138 (unsigned long)ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 goto bail;
140 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200141 if (le16_to_cpu(fnode->btree.first_free) !=
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 8 + fnode->btree.n_used_nodes * (fnode->btree.internal ? 8 : 12)) {
Randy Dunlap18debbb2006-12-06 20:37:05 -0800143 hpfs_error(s,
144 "bad first_free pointer in fnode %08lx",
145 (unsigned long)ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 goto bail;
147 }
148 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200149 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)) {
Randy Dunlap18debbb2006-12-06 20:37:05 -0800151 hpfs_error(s,
152 "bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x",
153 (unsigned long)ino,
Mikulas Patocka0b697602011-05-08 20:44:26 +0200154 le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 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) {
Randy Dunlap18debbb2006-12-06 20:37:05 -0800161 hpfs_error(s, "bad EA in fnode %08lx",
162 (unsigned long)ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 goto bail;
164 }
165 ea = next_ea(ea);
166 }
167 }
168 }
169 return fnode;
170 bail:
171 brelse(*bhp);
172 return NULL;
173}
174
175struct 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) {
Mikulas Patocka0b697602011-05-08 20:44:26 +0200181 if (le32_to_cpu(anode->magic) != ANODE_MAGIC) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 hpfs_error(s, "bad magic on anode %08x", ano);
183 goto bail;
184 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200185 if (le32_to_cpu(anode->self) != ano) {
186 hpfs_error(s, "self pointer invalid on anode %08x", ano);
187 goto bail;
188 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 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 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200194 if (le16_to_cpu(anode->btree.first_free) !=
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195 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
210struct 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;
Al Viro7e7742e2010-01-31 17:09:29 -0500224 unsigned char *d = (unsigned char *)dnode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 int b = 0;
Mikulas Patocka0b697602011-05-08 20:44:26 +0200226 if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 hpfs_error(s, "bad magic on dnode %08x", secno);
228 goto bail;
229 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200230 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));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 /* Check dirents - bad dirents would cause infinite
233 loops or shooting to memory */
Mikulas Patocka0b697602011-05-08 20:44:26 +0200234 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));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 goto bail;
237 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200238 for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 struct hpfs_dirent *de = (struct hpfs_dirent *)((char *)dnode + p);
Mikulas Patocka0b697602011-05-08 20:44:26 +0200240 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) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
242 goto bail;
243 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200244 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;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246 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 }
Mikulas Patocka0b697602011-05-08 20:44:26 +0200258 if (p != le32_to_cpu(dnode->first_free)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 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
274dnode_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
Mikulas Patocka0b697602011-05-08 20:44:26 +0200284 dno = le32_to_cpu(fnode->u.external[0].disk_secno);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 brelse(bh);
286 return dno;
287}