dmaengine: imx-dma: fix slow path issue in prep_dma_cyclic
[linux/fpc-iii.git] / fs / hpfs / map.c
blob3aa66ae1031e7f8b8c0ea8399b670daa308d3557
1 /*
2 * linux/fs/hpfs/map.c
4 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
6 * mapping structures to memory with some minimal checks
7 */
9 #include "hpfs_fn.h"
11 __le32 *hpfs_map_dnode_bitmap(struct super_block *s, struct quad_buffer_head *qbh)
13 return hpfs_map_4sectors(s, hpfs_sb(s)->sb_dmap, qbh, 0);
16 __le32 *hpfs_map_bitmap(struct super_block *s, unsigned bmp_block,
17 struct quad_buffer_head *qbh, char *id)
19 secno sec;
20 __le32 *ret;
21 unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
22 if (hpfs_sb(s)->sb_chk) if (bmp_block >= n_bands) {
23 hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x at %s", bmp_block, id);
24 return NULL;
26 sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
27 if (!sec || sec > hpfs_sb(s)->sb_fs_size-4) {
28 hpfs_error(s, "invalid bitmap block pointer %08x -> %08x at %s", bmp_block, sec, id);
29 return NULL;
31 ret = hpfs_map_4sectors(s, sec, qbh, 4);
32 if (ret) hpfs_prefetch_bitmap(s, bmp_block + 1);
33 return ret;
36 void hpfs_prefetch_bitmap(struct super_block *s, unsigned bmp_block)
38 unsigned to_prefetch, next_prefetch;
39 unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
40 if (unlikely(bmp_block >= n_bands))
41 return;
42 to_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
43 if (unlikely(bmp_block + 1 >= n_bands))
44 next_prefetch = 0;
45 else
46 next_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block + 1]);
47 hpfs_prefetch_sectors(s, to_prefetch, 4 + 4 * (to_prefetch + 4 == next_prefetch));
51 * Load first code page into kernel memory, return pointer to 256-byte array,
52 * first 128 bytes are uppercasing table for chars 128-255, next 128 bytes are
53 * lowercasing table
56 unsigned char *hpfs_load_code_page(struct super_block *s, secno cps)
58 struct buffer_head *bh;
59 secno cpds;
60 unsigned cpi;
61 unsigned char *ptr;
62 unsigned char *cp_table;
63 int i;
64 struct code_page_data *cpd;
65 struct code_page_directory *cp = hpfs_map_sector(s, cps, &bh, 0);
66 if (!cp) return NULL;
67 if (le32_to_cpu(cp->magic) != CP_DIR_MAGIC) {
68 printk("HPFS: Code page directory magic doesn't match (magic = %08x)\n", le32_to_cpu(cp->magic));
69 brelse(bh);
70 return NULL;
72 if (!le32_to_cpu(cp->n_code_pages)) {
73 printk("HPFS: n_code_pages == 0\n");
74 brelse(bh);
75 return NULL;
77 cpds = le32_to_cpu(cp->array[0].code_page_data);
78 cpi = le16_to_cpu(cp->array[0].index);
79 brelse(bh);
81 if (cpi >= 3) {
82 printk("HPFS: Code page index out of array\n");
83 return NULL;
86 if (!(cpd = hpfs_map_sector(s, cpds, &bh, 0))) return NULL;
87 if (le16_to_cpu(cpd->offs[cpi]) > 0x178) {
88 printk("HPFS: Code page index out of sector\n");
89 brelse(bh);
90 return NULL;
92 ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6;
93 if (!(cp_table = kmalloc(256, GFP_KERNEL))) {
94 printk("HPFS: out of memory for code page table\n");
95 brelse(bh);
96 return NULL;
98 memcpy(cp_table, ptr, 128);
99 brelse(bh);
101 /* Try to build lowercasing table from uppercasing one */
103 for (i=128; i<256; i++) cp_table[i]=i;
104 for (i=128; i<256; i++) if (cp_table[i-128]!=i && cp_table[i-128]>=128)
105 cp_table[cp_table[i-128]] = i;
107 return cp_table;
110 __le32 *hpfs_load_bitmap_directory(struct super_block *s, secno bmp)
112 struct buffer_head *bh;
113 int n = (hpfs_sb(s)->sb_fs_size + 0x200000 - 1) >> 21;
114 int i;
115 __le32 *b;
116 if (!(b = kmalloc(n * 512, GFP_KERNEL))) {
117 printk("HPFS: can't allocate memory for bitmap directory\n");
118 return NULL;
120 for (i=0;i<n;i++) {
121 __le32 *d = hpfs_map_sector(s, bmp+i, &bh, n - i - 1);
122 if (!d) {
123 kfree(b);
124 return NULL;
126 memcpy((char *)b + 512 * i, d, 512);
127 brelse(bh);
129 return b;
133 * Load fnode to memory
136 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t ino, struct buffer_head **bhp)
138 struct fnode *fnode;
139 if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ino, 1, "fnode")) {
140 return NULL;
142 if ((fnode = hpfs_map_sector(s, ino, bhp, FNODE_RD_AHEAD))) {
143 if (hpfs_sb(s)->sb_chk) {
144 struct extended_attribute *ea;
145 struct extended_attribute *ea_end;
146 if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) {
147 hpfs_error(s, "bad magic on fnode %08lx",
148 (unsigned long)ino);
149 goto bail;
151 if (!fnode_is_dir(fnode)) {
152 if ((unsigned)fnode->btree.n_used_nodes + (unsigned)fnode->btree.n_free_nodes !=
153 (bp_internal(&fnode->btree) ? 12 : 8)) {
154 hpfs_error(s,
155 "bad number of nodes in fnode %08lx",
156 (unsigned long)ino);
157 goto bail;
159 if (le16_to_cpu(fnode->btree.first_free) !=
160 8 + fnode->btree.n_used_nodes * (bp_internal(&fnode->btree) ? 8 : 12)) {
161 hpfs_error(s,
162 "bad first_free pointer in fnode %08lx",
163 (unsigned long)ino);
164 goto bail;
167 if (le16_to_cpu(fnode->ea_size_s) && (le16_to_cpu(fnode->ea_offs) < 0xc4 ||
168 le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200)) {
169 hpfs_error(s,
170 "bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x",
171 (unsigned long)ino,
172 le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
173 goto bail;
175 ea = fnode_ea(fnode);
176 ea_end = fnode_end_ea(fnode);
177 while (ea != ea_end) {
178 if (ea > ea_end) {
179 hpfs_error(s, "bad EA in fnode %08lx",
180 (unsigned long)ino);
181 goto bail;
183 ea = next_ea(ea);
187 return fnode;
188 bail:
189 brelse(*bhp);
190 return NULL;
193 struct anode *hpfs_map_anode(struct super_block *s, anode_secno ano, struct buffer_head **bhp)
195 struct anode *anode;
196 if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ano, 1, "anode")) return NULL;
197 if ((anode = hpfs_map_sector(s, ano, bhp, ANODE_RD_AHEAD)))
198 if (hpfs_sb(s)->sb_chk) {
199 if (le32_to_cpu(anode->magic) != ANODE_MAGIC) {
200 hpfs_error(s, "bad magic on anode %08x", ano);
201 goto bail;
203 if (le32_to_cpu(anode->self) != ano) {
204 hpfs_error(s, "self pointer invalid on anode %08x", ano);
205 goto bail;
207 if ((unsigned)anode->btree.n_used_nodes + (unsigned)anode->btree.n_free_nodes !=
208 (bp_internal(&anode->btree) ? 60 : 40)) {
209 hpfs_error(s, "bad number of nodes in anode %08x", ano);
210 goto bail;
212 if (le16_to_cpu(anode->btree.first_free) !=
213 8 + anode->btree.n_used_nodes * (bp_internal(&anode->btree) ? 8 : 12)) {
214 hpfs_error(s, "bad first_free pointer in anode %08x", ano);
215 goto bail;
218 return anode;
219 bail:
220 brelse(*bhp);
221 return NULL;
225 * Load dnode to memory and do some checks
228 struct dnode *hpfs_map_dnode(struct super_block *s, unsigned secno,
229 struct quad_buffer_head *qbh)
231 struct dnode *dnode;
232 if (hpfs_sb(s)->sb_chk) {
233 if (hpfs_chk_sectors(s, secno, 4, "dnode")) return NULL;
234 if (secno & 3) {
235 hpfs_error(s, "dnode %08x not byte-aligned", secno);
236 return NULL;
239 if ((dnode = hpfs_map_4sectors(s, secno, qbh, DNODE_RD_AHEAD)))
240 if (hpfs_sb(s)->sb_chk) {
241 unsigned p, pp = 0;
242 unsigned char *d = (unsigned char *)dnode;
243 int b = 0;
244 if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) {
245 hpfs_error(s, "bad magic on dnode %08x", secno);
246 goto bail;
248 if (le32_to_cpu(dnode->self) != secno)
249 hpfs_error(s, "bad self pointer on dnode %08x self = %08x", secno, le32_to_cpu(dnode->self));
250 /* Check dirents - bad dirents would cause infinite
251 loops or shooting to memory */
252 if (le32_to_cpu(dnode->first_free) > 2048) {
253 hpfs_error(s, "dnode %08x has first_free == %08x", secno, le32_to_cpu(dnode->first_free));
254 goto bail;
256 for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) {
257 struct hpfs_dirent *de = (struct hpfs_dirent *)((char *)dnode + p);
258 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) {
259 hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
260 goto bail;
262 if (((31 + de->namelen + de->down*4 + 3) & ~3) != le16_to_cpu(de->length)) {
263 if (((31 + de->namelen + de->down*4 + 3) & ~3) < le16_to_cpu(de->length) && s->s_flags & MS_RDONLY) goto ok;
264 hpfs_error(s, "namelen does not match dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
265 goto bail;
268 if (hpfs_sb(s)->sb_chk >= 2) b |= 1 << de->down;
269 if (de->down) if (de_down_pointer(de) < 0x10) {
270 hpfs_error(s, "bad down pointer in dnode %08x, dirent %03x, last %03x", secno, p, pp);
271 goto bail;
273 pp = p;
276 if (p != le32_to_cpu(dnode->first_free)) {
277 hpfs_error(s, "size on last dirent does not match first_free; dnode %08x", secno);
278 goto bail;
280 if (d[pp + 30] != 1 || d[pp + 31] != 255) {
281 hpfs_error(s, "dnode %08x does not end with \\377 entry", secno);
282 goto bail;
284 if (b == 3) printk("HPFS: warning: unbalanced dnode tree, dnode %08x; see hpfs.txt 4 more info\n", secno);
286 return dnode;
287 bail:
288 hpfs_brelse4(qbh);
289 return NULL;
292 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino)
294 struct buffer_head *bh;
295 struct fnode *fnode;
296 dnode_secno dno;
298 fnode = hpfs_map_fnode(s, ino, &bh);
299 if (!fnode)
300 return 0;
302 dno = le32_to_cpu(fnode->u.external[0].disk_secno);
303 brelse(bh);
304 return dno;