fs/hpfs/ea.c

   1 /*
   2  *  linux/fs/hpfs/ea.c
   3  *
   4  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   5  *
   6  *  handling extended attributes
   7  */
   8
   9 #include <linux/string.h>
  10 #include "hpfs_fn.h"
  11
  12 /* Remove external extended attributes. ano specifies wheter a is a
  13    direct sector where eas start or an anode */
  14
  15 void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
  16 {
  17         unsigned pos = 0;
  18         while (pos < len) {
  19                 char ex[4 + 255 + 1 + 8];
  20                 struct extended_attribute *ea = (struct extended_attribute *)ex;
  21                 if (pos + 4 > len) {
  22                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
  23                                 ano ? "anode" : "sectors", a, len);
  24                         return;
  25                 }
  26                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
  27                 if (ea->indirect) {
  28                         if (ea->valuelen != 8) {
  29                                 hpfs_error(s, "ea->indirect set while ea->valuelen!=8, %s %08x, pos %08x",
  30                                         ano ? "anode" : "sectors", a, pos);
  31                                 return;
  32                         }
  33                         if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
  34                                 return;
  35                         hpfs_ea_remove(s, ea_sec(ea), ea->anode, ea_len(ea));
  36                 }
  37                 pos += ea->namelen + ea->valuelen + 5;
  38         }
  39         if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
  40         else {
  41                 struct buffer_head *bh;
  42                 struct anode *anode;
  43                 if ((anode = hpfs_map_anode(s, a, &bh))) {
  44                         hpfs_remove_btree(s, &anode->btree);
  45                         brelse(bh);
  46                         hpfs_free_sectors(s, a, 1);
  47                 }
  48         }
  49 }
  50
  51 static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
  52 {
  53         char *ret;
  54         if (!(ret = kmalloc(size + 1, GFP_KERNEL))) {
  55                 printk("HPFS: out of memory for EA\n");
  56                 return NULL;
  57         }
  58         if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
  59                 kfree(ret);
  60                 return NULL;
  61         }
  62         ret[size] = 0;
  63         return ret;
  64 }
  65
  66 static void set_indirect_ea(struct super_block *s, int ano, secno a, char *data,
  67                             int size)
  68 {
  69         hpfs_ea_write(s, a, ano, 0, size, data);
  70 }
  71
  72 /* Read an extended attribute named 'key' into the provided buffer */
  73
  74 int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
  75                 char *buf, int size)
  76 {
  77         unsigned pos;
  78         int ano, len;
  79         secno a;
  80         struct extended_attribute *ea;
  81         struct extended_attribute *ea_end = fnode_end_ea(fnode);
  82         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
  83                 if (!strcmp(ea->name, key)) {
  84                         if (ea->indirect)
  85                                 goto indirect;
  86                         if (ea->valuelen >= size)
  87                                 return -EINVAL;
  88                         memcpy(buf, ea_data(ea), ea->valuelen);
  89                         buf[ea->valuelen] = 0;
  90                         return 0;
  91                 }
  92         a = fnode->ea_secno;
  93         len = fnode->ea_size_l;
  94         ano = fnode->ea_anode;
  95         pos = 0;
  96         while (pos < len) {
  97                 char ex[4 + 255 + 1 + 8];
  98                 ea = (struct extended_attribute *)ex;
  99                 if (pos + 4 > len) {
 100                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 101                                 ano ? "anode" : "sectors", a, len);
 102                         return -EIO;
 103                 }
 104                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
 105                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
 106                         return -EIO;
 107                 if (!strcmp(ea->name, key)) {
 108                         if (ea->indirect)
 109                                 goto indirect;
 110                         if (ea->valuelen >= size)
 111                                 return -EINVAL;
 112                         if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea->valuelen, buf))
 113                                 return -EIO;
 114                         buf[ea->valuelen] = 0;
 115                         return 0;
 116                 }
 117                 pos += ea->namelen + ea->valuelen + 5;
 118         }
 119         return -ENOENT;
 120 indirect:
 121         if (ea_len(ea) >= size)
 122                 return -EINVAL;
 123         if (hpfs_ea_read(s, ea_sec(ea), ea->anode, 0, ea_len(ea), buf))
 124                 return -EIO;
 125         buf[ea_len(ea)] = 0;
 126         return 0;
 127 }
 128
 129 /* Read an extended attribute named 'key' */
 130 char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
 131 {
 132         char *ret;
 133         unsigned pos;
 134         int ano, len;
 135         secno a;
 136         struct extended_attribute *ea;
 137         struct extended_attribute *ea_end = fnode_end_ea(fnode);
 138         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 139                 if (!strcmp(ea->name, key)) {
 140                         if (ea->indirect)
 141                                 return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
 142                         if (!(ret = kmalloc((*size = ea->valuelen) + 1, GFP_KERNEL))) {
 143                                 printk("HPFS: out of memory for EA\n");
 144                                 return NULL;
 145                         }
 146                         memcpy(ret, ea_data(ea), ea->valuelen);
 147                         ret[ea->valuelen] = 0;
 148                         return ret;
 149                 }
 150         a = fnode->ea_secno;
 151         len = fnode->ea_size_l;
 152         ano = fnode->ea_anode;
 153         pos = 0;
 154         while (pos < len) {
 155                 char ex[4 + 255 + 1 + 8];
 156                 ea = (struct extended_attribute *)ex;
 157                 if (pos + 4 > len) {
 158                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 159                                 ano ? "anode" : "sectors", a, len);
 160                         return NULL;
 161                 }
 162                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
 163                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
 164                         return NULL;
 165                 if (!strcmp(ea->name, key)) {
 166                         if (ea->indirect)
 167                                 return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
 168                         if (!(ret = kmalloc((*size = ea->valuelen) + 1, GFP_KERNEL))) {
 169                                 printk("HPFS: out of memory for EA\n");
 170                                 return NULL;
 171                         }
 172                         if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea->valuelen, ret)) {
 173                                 kfree(ret);
 174                                 return NULL;
 175                         }
 176                         ret[ea->valuelen] = 0;
 177                         return ret;
 178                 }
 179                 pos += ea->namelen + ea->valuelen + 5;
 180         }
 181         return NULL;
 182 }
 183
 184 /*
 185  * Update or create extended attribute 'key' with value 'data'. Note that
 186  * when this ea exists, it MUST have the same size as size of data.
 187  * This driver can't change sizes of eas ('cause I just don't need it).
 188  */
 189
 190 void hpfs_set_ea(struct inode *inode, struct fnode *fnode, char *key, char *data, int size)
 191 {
 192         fnode_secno fno = inode->i_ino;
 193         struct super_block *s = inode->i_sb;
 194         unsigned pos;
 195         int ano, len;
 196         secno a;
 197         unsigned char h[4];
 198         struct extended_attribute *ea;
 199         struct extended_attribute *ea_end = fnode_end_ea(fnode);
 200         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 201                 if (!strcmp(ea->name, key)) {
 202                         if (ea->indirect) {
 203                                 if (ea_len(ea) == size)
 204                                         set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
 205                         } else if (ea->valuelen == size) {
 206                                 memcpy(ea_data(ea), data, size);
 207                         }
 208                         return;
 209                 }
 210         a = fnode->ea_secno;
 211         len = fnode->ea_size_l;
 212         ano = fnode->ea_anode;
 213         pos = 0;
 214         while (pos < len) {
 215                 char ex[4 + 255 + 1 + 8];
 216                 ea = (struct extended_attribute *)ex;
 217                 if (pos + 4 > len) {
 218                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 219                                 ano ? "anode" : "sectors", a, len);
 220                         return;
 221                 }
 222                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
 223                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
 224                         return;
 225                 if (!strcmp(ea->name, key)) {
 226                         if (ea->indirect) {
 227                                 if (ea_len(ea) == size)
 228                                         set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
 229                         }
 230                         else {
 231                                 if (ea->valuelen == size)
 232                                         hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
 233                         }
 234                         return;
 235                 }
 236                 pos += ea->namelen + ea->valuelen + 5;
 237         }
 238         if (!fnode->ea_size_s) {
 239                 /*if (fnode->ea_size_s) {
 240                         hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
 241                                 inode->i_ino, fnode->ea_size_s);
 242                         return;
 243                 }*/
 244                 fnode->ea_offs = 0xc4;
 245         }
 246         if (fnode->ea_offs < 0xc4 || fnode->ea_offs + fnode->ea_size_s > 0x200) {
 247                 hpfs_error(s, "fnode %08x: ea_offs == %03x, ea_size_s == %03x",
 248                         inode->i_ino, fnode->ea_offs, fnode->ea_size_s);
 249                 return;
 250         }
 251         if ((fnode->ea_size_s || !fnode->ea_size_l) &&
 252              fnode->ea_offs + fnode->ea_size_s + strlen(key) + size + 5 <= 0x200) {
 253                 /* I'm not sure ... maybe we overwrite ACL here. I have no info
 254                    on it right now :-( */
 255                 ea = fnode_end_ea(fnode);
 256                 *(char *)ea = 0;
 257                 ea->namelen = strlen(key);
 258                 ea->valuelen = size;
 259                 strcpy(ea->name, key);
 260                 memcpy(ea_data(ea), data, size);
 261                 fnode->ea_size_s += strlen(key) + size + 5;
 262                 goto ret;
 263         }
 264         /* Most the code here is 99.9993422% unused. I hope there are no bugs.
 265            But what .. HPFS.IFS has also bugs in ea management. */
 266         if (fnode->ea_size_s && !fnode->ea_size_l) {
 267                 secno n;
 268                 struct buffer_head *bh;
 269                 char *data;
 270                 if (!(n = hpfs_alloc_sector(s, fno, 1, 0, 1))) return;
 271                 if (!(data = hpfs_get_sector(s, n, &bh))) {
 272                         hpfs_free_sectors(s, n, 1);
 273                         return;
 274                 }
 275                 memcpy(data, fnode_ea(fnode), fnode->ea_size_s);
 276                 fnode->ea_size_l = fnode->ea_size_s;
 277                 fnode->ea_size_s = 0;
 278                 fnode->ea_secno = n;
 279                 fnode->ea_anode = 0;
 280                 mark_buffer_dirty(bh);
 281                 brelse(bh);
 282         }
 283         pos = fnode->ea_size_l + 5 + strlen(key) + size;
 284         len = (fnode->ea_size_l + 511) >> 9;
 285         if (pos >= 30000) goto bail;
 286         while (((pos + 511) >> 9) > len) {
 287                 if (!len) {
 288                         if (!(fnode->ea_secno = hpfs_alloc_sector(s, fno, 1, 0, 1)))
 289                                 goto bail;
 290                         fnode->ea_anode = 0;
 291                         len++;
 292                 } else if (!fnode->ea_anode) {
 293                         if (hpfs_alloc_if_possible(s, fnode->ea_secno + len)) {
 294                                 len++;
 295                         } else {
 296                                 /* Aargh... don't know how to create ea anodes :-( */
 297                                 /*struct buffer_head *bh;
 298                                 struct anode *anode;
 299                                 anode_secno a_s;
 300                                 if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
 301                                         goto bail;
 302                                 anode->up = fno;
 303                                 anode->btree.fnode_parent = 1;
 304                                 anode->btree.n_free_nodes--;
 305                                 anode->btree.n_used_nodes++;
 306                                 anode->btree.first_free += 12;
 307                                 anode->u.external[0].disk_secno = fnode->ea_secno;
 308                                 anode->u.external[0].file_secno = 0;
 309                                 anode->u.external[0].length = len;
 310                                 mark_buffer_dirty(bh);
 311                                 brelse(bh);
 312                                 fnode->ea_anode = 1;
 313                                 fnode->ea_secno = a_s;*/
 314                                 secno new_sec;
 315                                 int i;
 316                                 if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9), 1)))
 317                                         goto bail;
 318                                 for (i = 0; i < len; i++) {
 319                                         struct buffer_head *bh1, *bh2;
 320                                         void *b1, *b2;
 321                                         if (!(b1 = hpfs_map_sector(s, fnode->ea_secno + i, &bh1, len - i - 1))) {
 322                                                 hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 323                                                 goto bail;
 324                                         }
 325                                         if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
 326                                                 brelse(bh1);
 327                                                 hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 328                                                 goto bail;
 329                                         }
 330                                         memcpy(b2, b1, 512);
 331                                         brelse(bh1);
 332                                         mark_buffer_dirty(bh2);
 333                                         brelse(bh2);
 334                                 }
 335                                 hpfs_free_sectors(s, fnode->ea_secno, len);
 336                                 fnode->ea_secno = new_sec;
 337                                 len = (pos + 511) >> 9;
 338                         }
 339                 }
 340                 if (fnode->ea_anode) {
 341                         if (hpfs_add_sector_to_btree(s, fnode->ea_secno,
 342                                                      0, len) != -1) {
 343                                 len++;
 344                         } else {
 345                                 goto bail;
 346                         }
 347                 }
 348         }
 349         h[0] = 0;
 350         h[1] = strlen(key);
 351         h[2] = size & 0xff;
 352         h[3] = size >> 8;
 353         if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l, 4, h)) goto bail;
 354         if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 4, h[1] + 1, key)) goto bail;
 355         if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 5 + h[1], size, data)) goto bail;
 356         fnode->ea_size_l = pos;
 357         ret:
 358         inode->i_hpfs_ea_size += 5 + strlen(key) + size;
 359         return;
 360         bail:
 361         if (fnode->ea_secno)
 362                 if (fnode->ea_anode) hpfs_truncate_btree(s, fnode->ea_secno, 1, (fnode->ea_size_l + 511) >> 9);
 363                 else hpfs_free_sectors(s, fnode->ea_secno + ((fnode->ea_size_l + 511) >> 9), len - ((fnode->ea_size_l + 511) >> 9));
 364         else fnode->ea_secno = fnode->ea_size_l = 0;
 365 }
 366