LXR linux-old/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 whether a is a 
  13   direct sector where eas starts or an anode */
  14
  15void 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
  51static 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
  66static 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
  74int 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;
 120indirect:
 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' */
 130char *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
 190void 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_offs) {
 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->acl_size_s + 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->acl_size_s + fnode->ea_size_s + strlen(key) + size + 5 <= 0x200) {
 253                ea = fnode_end_ea(fnode);
 254                *(char *)ea = 0;
 255                ea->namelen = strlen(key);
 256                ea->valuelen = size;
 257                strcpy(ea->name, key);
 258                memcpy(ea_data(ea), data, size);
 259                fnode->ea_size_s += strlen(key) + size + 5;
 260                goto ret;
 261        }
 262        /* Most the code here is 99.9993422% unused. I hope there are no bugs.
 263           But what .. HPFS.IFS has also bugs in ea management. */
 264        if (fnode->ea_size_s && !fnode->ea_size_l) {
 265                secno n;
 266                struct buffer_head *bh;
 267                char *data;
 268                if (!(n = hpfs_alloc_sector(s, fno, 1, 0, 1))) return;
 269                if (!(data = hpfs_get_sector(s, n, &bh))) {
 270                        hpfs_free_sectors(s, n, 1);
 271                        return;
 272                }
 273                memcpy(data, fnode_ea(fnode), fnode->ea_size_s);
 274                fnode->ea_size_l = fnode->ea_size_s;
 275                fnode->ea_size_s = 0;
 276                fnode->ea_secno = n;
 277                fnode->ea_anode = 0;
 278                mark_buffer_dirty(bh);
 279                brelse(bh);
 280        }
 281        pos = fnode->ea_size_l + 5 + strlen(key) + size;
 282        len = (fnode->ea_size_l + 511) >> 9;
 283        if (pos >= 30000) goto bail;
 284        while (((pos + 511) >> 9) > len) {
 285                if (!len) {
 286                        if (!(fnode->ea_secno = hpfs_alloc_sector(s, fno, 1, 0, 1)))
 287                                goto bail;
 288                        fnode->ea_anode = 0;
 289                        len++;
 290                } else if (!fnode->ea_anode) {
 291                        if (hpfs_alloc_if_possible(s, fnode->ea_secno + len)) {
 292                                len++;
 293                        } else {
 294                                /* Aargh... don't know how to create ea anodes :-( */
 295                                /*struct buffer_head *bh;
 296                                struct anode *anode;
 297                                anode_secno a_s;
 298                                if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
 299                                        goto bail;
 300                                anode->up = fno;
 301                                anode->btree.fnode_parent = 1;
 302                                anode->btree.n_free_nodes--;
 303                                anode->btree.n_used_nodes++;
 304                                anode->btree.first_free += 12;
 305                                anode->u.external[0].disk_secno = fnode->ea_secno;
 306                                anode->u.external[0].file_secno = 0;
 307                                anode->u.external[0].length = len;
 308                                mark_buffer_dirty(bh);
 309                                brelse(bh);
 310                                fnode->ea_anode = 1;
 311                                fnode->ea_secno = a_s;*/
 312                                secno new_sec;
 313                                int i;
 314                                if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9), 1)))
 315                                        goto bail;
 316                                for (i = 0; i < len; i++) {
 317                                        struct buffer_head *bh1, *bh2;
 318                                        void *b1, *b2;
 319                                        if (!(b1 = hpfs_map_sector(s, fnode->ea_secno + i, &bh1, len - i - 1))) {
 320                                                hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 321                                                goto bail;
 322                                        }
 323                                        if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
 324                                                brelse(bh1);
 325                                                hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 326                                                goto bail;
 327                                        }
 328                                        memcpy(b2, b1, 512);
 329                                        brelse(bh1);
 330                                        mark_buffer_dirty(bh2);
 331                                        brelse(bh2);
 332                                }
 333                                hpfs_free_sectors(s, fnode->ea_secno, len);
 334                                fnode->ea_secno = new_sec;
 335                                len = (pos + 511) >> 9;
 336                        }
 337                }
 338                if (fnode->ea_anode) {
 339                        if (hpfs_add_sector_to_btree(s, fnode->ea_secno,
 340                                                     0, len) != -1) {
 341                                len++;
 342                        } else {
 343                                goto bail;
 344                        }
 345                }
 346        }
 347        h[0] = 0;
 348        h[1] = strlen(key);
 349        h[2] = size & 0xff;
 350        h[3] = size >> 8;
 351        if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l, 4, h)) goto bail;
 352        if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 4, h[1] + 1, key)) goto bail;
 353        if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 5 + h[1], size, data)) goto bail;
 354        fnode->ea_size_l = pos;
 355        ret:
 356        inode->i_hpfs_ea_size += 5 + strlen(key) + size;
 357        return;
 358        bail:
 359        if (fnode->ea_secno)
 360                if (fnode->ea_anode) hpfs_truncate_btree(s, fnode->ea_secno, 1, (fnode->ea_size_l + 511) >> 9);
 361                else hpfs_free_sectors(s, fnode->ea_secno + ((fnode->ea_size_l + 511) >> 9), len - ((fnode->ea_size_l + 511) >> 9));
 362        else fnode->ea_secno = fnode->ea_size_l = 0;
 363}
 364        
 365