LXR linux/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 "hpfs_fn.h"
  10
  11/* Remove external extended attributes. ano specifies whether a is a 
  12   direct sector where eas starts or an anode */
  13
  14void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
  15{
  16        unsigned pos = 0;
  17        while (pos < len) {
  18                char ex[4 + 255 + 1 + 8];
  19                struct extended_attribute *ea = (struct extended_attribute *)ex;
  20                if (pos + 4 > len) {
  21                        hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
  22                                ano ? "anode" : "sectors", a, len);
  23                        return;
  24                }
  25                if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
  26                if (ea_indirect(ea)) {
  27                        if (ea_valuelen(ea) != 8) {
  28                                hpfs_error(s, "ea_indirect(ea) set while ea->valuelen!=8, %s %08x, pos %08x",
  29                                        ano ? "anode" : "sectors", a, pos);
  30                                return;
  31                        }
  32                        if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
  33                                return;
  34                        hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
  35                }
  36                pos += ea->namelen + ea_valuelen(ea) + 5;
  37        }
  38        if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
  39        else {
  40                struct buffer_head *bh;
  41                struct anode *anode;
  42                if ((anode = hpfs_map_anode(s, a, &bh))) {
  43                        hpfs_remove_btree(s, &anode->btree);
  44                        brelse(bh);
  45                        hpfs_free_sectors(s, a, 1);
  46                }
  47        }
  48}
  49
  50static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
  51{
  52        char *ret;
  53        if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
  54                pr_err("out of memory for EA\n");
  55                return NULL;
  56        }
  57        if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
  58                kfree(ret);
  59                return NULL;
  60        }
  61        ret[size] = 0;
  62        return ret;
  63}
  64
  65static void set_indirect_ea(struct super_block *s, int ano, secno a,
  66                            const char *data, int size)
  67{
  68        hpfs_ea_write(s, a, ano, 0, size, data);
  69}
  70
  71/* Read an extended attribute named 'key' into the provided buffer */
  72
  73int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
  74                char *buf, int size)
  75{
  76        unsigned pos;
  77        int ano, len;
  78        secno a;
  79        char ex[4 + 255 + 1 + 8];
  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(ea))
  85                                goto indirect;
  86                        if (ea_valuelen(ea) >= size)
  87                                return -EINVAL;
  88                        memcpy(buf, ea_data(ea), ea_valuelen(ea));
  89                        buf[ea_valuelen(ea)] = 0;
  90                        return 0;
  91                }
  92        a = le32_to_cpu(fnode->ea_secno);
  93        len = le32_to_cpu(fnode->ea_size_l);
  94        ano = fnode_in_anode(fnode);
  95        pos = 0;
  96        while (pos < len) {
  97                ea = (struct extended_attribute *)ex;
  98                if (pos + 4 > len) {
  99                        hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 100                                ano ? "anode" : "sectors", a, len);
 101                        return -EIO;
 102                }
 103                if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
 104                if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
 105                        return -EIO;
 106                if (!strcmp(ea->name, key)) {
 107                        if (ea_indirect(ea))
 108                                goto indirect;
 109                        if (ea_valuelen(ea) >= size)
 110                                return -EINVAL;
 111                        if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), buf))
 112                                return -EIO;
 113                        buf[ea_valuelen(ea)] = 0;
 114                        return 0;
 115                }
 116                pos += ea->namelen + ea_valuelen(ea) + 5;
 117        }
 118        return -ENOENT;
 119indirect:
 120        if (ea_len(ea) >= size)
 121                return -EINVAL;
 122        if (hpfs_ea_read(s, ea_sec(ea), ea_in_anode(ea), 0, ea_len(ea), buf))
 123                return -EIO;
 124        buf[ea_len(ea)] = 0;
 125        return 0;
 126}
 127
 128/* Read an extended attribute named 'key' */
 129char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
 130{
 131        char *ret;
 132        unsigned pos;
 133        int ano, len;
 134        secno a;
 135        struct extended_attribute *ea;
 136        struct extended_attribute *ea_end = fnode_end_ea(fnode);
 137        for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 138                if (!strcmp(ea->name, key)) {
 139                        if (ea_indirect(ea))
 140                                return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
 141                        if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
 142                                pr_err("out of memory for EA\n");
 143                                return NULL;
 144                        }
 145                        memcpy(ret, ea_data(ea), ea_valuelen(ea));
 146                        ret[ea_valuelen(ea)] = 0;
 147                        return ret;
 148                }
 149        a = le32_to_cpu(fnode->ea_secno);
 150        len = le32_to_cpu(fnode->ea_size_l);
 151        ano = fnode_in_anode(fnode);
 152        pos = 0;
 153        while (pos < len) {
 154                char ex[4 + 255 + 1 + 8];
 155                ea = (struct extended_attribute *)ex;
 156                if (pos + 4 > len) {
 157                        hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 158                                ano ? "anode" : "sectors", a, len);
 159                        return NULL;
 160                }
 161                if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
 162                if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
 163                        return NULL;
 164                if (!strcmp(ea->name, key)) {
 165                        if (ea_indirect(ea))
 166                                return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
 167                        if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
 168                                pr_err("out of memory for EA\n");
 169                                return NULL;
 170                        }
 171                        if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), ret)) {
 172                                kfree(ret);
 173                                return NULL;
 174                        }
 175                        ret[ea_valuelen(ea)] = 0;
 176                        return ret;
 177                }
 178                pos += ea->namelen + ea_valuelen(ea) + 5;
 179        }
 180        return NULL;
 181}
 182
 183/* 
 184 * Update or create extended attribute 'key' with value 'data'. Note that
 185 * when this ea exists, it MUST have the same size as size of data.
 186 * This driver can't change sizes of eas ('cause I just don't need it).
 187 */
 188
 189void hpfs_set_ea(struct inode *inode, struct fnode *fnode, const char *key,
 190                 const 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(ea)) {
 203                                if (ea_len(ea) == size)
 204                                        set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
 205                        } else if (ea_valuelen(ea) == size) {
 206                                memcpy(ea_data(ea), data, size);
 207                        }
 208                        return;
 209                }
 210        a = le32_to_cpu(fnode->ea_secno);
 211        len = le32_to_cpu(fnode->ea_size_l);
 212        ano = fnode_in_anode(fnode);
 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(ea) ? 8 : 0), ex + 4))
 224                        return;
 225                if (!strcmp(ea->name, key)) {
 226                        if (ea_indirect(ea)) {
 227                                if (ea_len(ea) == size)
 228                                        set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
 229                        }
 230                        else {
 231                                if (ea_valuelen(ea) == 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(ea) + 5;
 237        }
 238        if (!le16_to_cpu(fnode->ea_offs)) {
 239                /*if (le16_to_cpu(fnode->ea_size_s)) {
 240                        hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
 241                                inode->i_ino, le16_to_cpu(fnode->ea_size_s));
 242                        return;
 243                }*/
 244                fnode->ea_offs = cpu_to_le16(0xc4);
 245        }
 246        if (le16_to_cpu(fnode->ea_offs) < 0xc4 || le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200) {
 247                hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
 248                        (unsigned long)inode->i_ino,
 249                        le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
 250                return;
 251        }
 252        if ((le16_to_cpu(fnode->ea_size_s) || !le32_to_cpu(fnode->ea_size_l)) &&
 253             le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5 <= 0x200) {
 254                ea = fnode_end_ea(fnode);
 255                *(char *)ea = 0;
 256                ea->namelen = strlen(key);
 257                ea->valuelen_lo = size;
 258                ea->valuelen_hi = size >> 8;
 259                strcpy(ea->name, key);
 260                memcpy(ea_data(ea), data, size);
 261                fnode->ea_size_s = cpu_to_le16(le16_to_cpu(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 (le16_to_cpu(fnode->ea_size_s) && !le32_to_cpu(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))) 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), le16_to_cpu(fnode->ea_size_s));
 276                fnode->ea_size_l = cpu_to_le32(le16_to_cpu(fnode->ea_size_s));
 277                fnode->ea_size_s = cpu_to_le16(0);
 278                fnode->ea_secno = cpu_to_le32(n);
 279                fnode->flags &= ~FNODE_anode;
 280                mark_buffer_dirty(bh);
 281                brelse(bh);
 282        }
 283        pos = le32_to_cpu(fnode->ea_size_l) + 5 + strlen(key) + size;
 284        len = (le32_to_cpu(fnode->ea_size_l) + 511) >> 9;
 285        if (pos >= 30000) goto bail;
 286        while (((pos + 511) >> 9) > len) {
 287                if (!len) {
 288                        secno q = hpfs_alloc_sector(s, fno, 1, 0);
 289                        if (!q) goto bail;
 290                        fnode->ea_secno = cpu_to_le32(q);
 291                        fnode->flags &= ~FNODE_anode;
 292                        len++;
 293                } else if (!fnode_in_anode(fnode)) {
 294                        if (hpfs_alloc_if_possible(s, le32_to_cpu(fnode->ea_secno) + len)) {
 295                                len++;
 296                        } else {
 297                                /* Aargh... don't know how to create ea anodes :-( */
 298                                /*struct buffer_head *bh;
 299                                struct anode *anode;
 300                                anode_secno a_s;
 301                                if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
 302                                        goto bail;
 303                                anode->up = cpu_to_le32(fno);
 304                                anode->btree.fnode_parent = 1;
 305                                anode->btree.n_free_nodes--;
 306                                anode->btree.n_used_nodes++;
 307                                anode->btree.first_free = cpu_to_le16(le16_to_cpu(anode->btree.first_free) + 12);
 308                                anode->u.external[0].disk_secno = cpu_to_le32(le32_to_cpu(fnode->ea_secno));
 309                                anode->u.external[0].file_secno = cpu_to_le32(0);
 310                                anode->u.external[0].length = cpu_to_le32(len);
 311                                mark_buffer_dirty(bh);
 312                                brelse(bh);
 313                                fnode->flags |= FNODE_anode;
 314                                fnode->ea_secno = cpu_to_le32(a_s);*/
 315                                secno new_sec;
 316                                int i;
 317                                if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9))))
 318                                        goto bail;
 319                                for (i = 0; i < len; i++) {
 320                                        struct buffer_head *bh1, *bh2;
 321                                        void *b1, *b2;
 322                                        if (!(b1 = hpfs_map_sector(s, le32_to_cpu(fnode->ea_secno) + i, &bh1, len - i - 1))) {
 323                                                hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 324                                                goto bail;
 325                                        }
 326                                        if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
 327                                                brelse(bh1);
 328                                                hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 329                                                goto bail;
 330                                        }
 331                                        memcpy(b2, b1, 512);
 332                                        brelse(bh1);
 333                                        mark_buffer_dirty(bh2);
 334                                        brelse(bh2);
 335                                }
 336                                hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno), len);
 337                                fnode->ea_secno = cpu_to_le32(new_sec);
 338                                len = (pos + 511) >> 9;
 339                        }
 340                }
 341                if (fnode_in_anode(fnode)) {
 342                        if (hpfs_add_sector_to_btree(s, le32_to_cpu(fnode->ea_secno),
 343                                                     0, len) != -1) {
 344                                len++;
 345                        } else {
 346                                goto bail;
 347                        }
 348                }
 349        }
 350        h[0] = 0;
 351        h[1] = strlen(key);
 352        h[2] = size & 0xff;
 353        h[3] = size >> 8;
 354        if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l), 4, h)) goto bail;
 355        if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 4, h[1] + 1, key)) goto bail;
 356        if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 5 + h[1], size, data)) goto bail;
 357        fnode->ea_size_l = cpu_to_le32(pos);
 358        ret:
 359        hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
 360        return;
 361        bail:
 362        if (le32_to_cpu(fnode->ea_secno))
 363                if (fnode_in_anode(fnode)) hpfs_truncate_btree(s, le32_to_cpu(fnode->ea_secno), 1, (le32_to_cpu(fnode->ea_size_l) + 511) >> 9);
 364                else hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno) + ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9), len - ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9));
 365        else fnode->ea_secno = fnode->ea_size_l = cpu_to_le32(0);
 366}
 367        
 368