spin_unlock(&MSDOS_I(inode)->cache_lru_lock);
}
-static int __fat_access(struct super_block *sb, int nr, int new_value)
-{
- struct msdos_sb_info *sbi = MSDOS_SB(sb);
- struct buffer_head *bh, *bh2, *c_bh, *c_bh2;
- unsigned char *p_first, *p_last;
- int copy, first, last, next, b;
-
- if (sbi->fat_bits == 32) {
- first = last = nr*4;
- } else if (sbi->fat_bits == 16) {
- first = last = nr*2;
- } else {
- first = nr*3/2;
- last = first+1;
- }
- b = sbi->fat_start + (first >> sb->s_blocksize_bits);
- if (!(bh = sb_bread(sb, b))) {
- printk(KERN_ERR "FAT: bread(block %d) in"
- " fat_access failed\n", b);
- return -EIO;
- }
- if ((first >> sb->s_blocksize_bits) == (last >> sb->s_blocksize_bits)) {
- bh2 = bh;
- } else {
- if (!(bh2 = sb_bread(sb, b + 1))) {
- brelse(bh);
- printk(KERN_ERR "FAT: bread(block %d) in"
- " fat_access failed\n", b + 1);
- return -EIO;
- }
- }
- if (sbi->fat_bits == 32) {
- p_first = p_last = NULL; /* GCC needs that stuff */
- next = le32_to_cpu(((__le32 *) bh->b_data)[(first &
- (sb->s_blocksize - 1)) >> 2]);
- /* Fscking Microsoft marketing department. Their "32" is 28. */
- next &= 0x0fffffff;
- } else if (sbi->fat_bits == 16) {
- p_first = p_last = NULL; /* GCC needs that stuff */
- next = le16_to_cpu(((__le16 *) bh->b_data)[(first &
- (sb->s_blocksize - 1)) >> 1]);
- } else {
- p_first = &((__u8 *)bh->b_data)[first & (sb->s_blocksize - 1)];
- p_last = &((__u8 *)bh2->b_data)[(first + 1) & (sb->s_blocksize - 1)];
- if (nr & 1)
- next = ((*p_first >> 4) | (*p_last << 4)) & 0xfff;
- else
- next = (*p_first+(*p_last << 8)) & 0xfff;
- }
- if (new_value != -1) {
- if (sbi->fat_bits == 32) {
- ((__le32 *)bh->b_data)[(first & (sb->s_blocksize - 1)) >> 2]
- = cpu_to_le32(new_value);
- } else if (sbi->fat_bits == 16) {
- ((__le16 *)bh->b_data)[(first & (sb->s_blocksize - 1)) >> 1]
- = cpu_to_le16(new_value);
- } else {
- if (nr & 1) {
- *p_first = (*p_first & 0xf) | (new_value << 4);
- *p_last = new_value >> 4;
- }
- else {
- *p_first = new_value & 0xff;
- *p_last = (*p_last & 0xf0) | (new_value >> 8);
- }
- mark_buffer_dirty(bh2);
- }
- mark_buffer_dirty(bh);
- for (copy = 1; copy < sbi->fats; copy++) {
- b = sbi->fat_start + (first >> sb->s_blocksize_bits)
- + sbi->fat_length * copy;
- if (!(c_bh = sb_bread(sb, b)))
- break;
- if (bh != bh2) {
- if (!(c_bh2 = sb_bread(sb, b+1))) {
- brelse(c_bh);
- break;
- }
- memcpy(c_bh2->b_data, bh2->b_data, sb->s_blocksize);
- mark_buffer_dirty(c_bh2);
- brelse(c_bh2);
- }
- memcpy(c_bh->b_data, bh->b_data, sb->s_blocksize);
- mark_buffer_dirty(c_bh);
- brelse(c_bh);
- }
- }
- brelse(bh);
- if (bh != bh2)
- brelse(bh2);
- return next;
-}
-
-/*
- * Returns the this'th FAT entry, -1 if it is an end-of-file entry. If
- * new_value is != -1, that FAT entry is replaced by it.
- */
-int fat_access(struct super_block *sb, int nr, int new_value)
-{
- int next;
-
- next = -EIO;
- if (nr < FAT_START_ENT || MSDOS_SB(sb)->max_cluster <= nr) {
- fat_fs_panic(sb, "invalid access to FAT (entry 0x%08x)", nr);
- goto out;
- }
- if (new_value == FAT_ENT_EOF)
- new_value = EOF_FAT(sb);
-
- next = __fat_access(sb, nr, new_value);
- if (next < 0)
- goto out;
- if (next >= BAD_FAT(sb))
- next = FAT_ENT_EOF;
-out:
- return next;
-}
-
static inline int cache_contiguous(struct fat_cache_id *cid, int dclus)
{
cid->nr_contig++;
{
struct super_block *sb = inode->i_sb;
const int limit = sb->s_maxbytes >> MSDOS_SB(sb)->cluster_bits;
+ struct fat_entry fatent;
struct fat_cache_id cid;
int nr;
cache_init(&cid, -1, -1);
}
+ fatent_init(&fatent);
while (*fclus < cluster) {
/* prevent the infinite loop of cluster chain */
if (*fclus > limit) {
fat_fs_panic(sb, "%s: detected the cluster chain loop"
" (i_pos %lld)", __FUNCTION__,
MSDOS_I(inode)->i_pos);
- return -EIO;
+ nr = -EIO;
+ goto out;
}
- nr = fat_access(sb, *dclus, -1);
+ nr = fat_ent_read(inode, &fatent, *dclus);
if (nr < 0)
- return nr;
+ goto out;
else if (nr == FAT_ENT_FREE) {
fat_fs_panic(sb, "%s: invalid cluster chain"
" (i_pos %lld)", __FUNCTION__,
MSDOS_I(inode)->i_pos);
- return -EIO;
+ nr = -EIO;
+ goto out;
} else if (nr == FAT_ENT_EOF) {
fat_cache_add(inode, &cid);
- return FAT_ENT_EOF;
+ goto out;
}
(*fclus)++;
*dclus = nr;
if (!cache_contiguous(&cid, *dclus))
cache_init(&cid, *fclus, *dclus);
}
+ nr = 0;
fat_cache_add(inode, &cid);
- return 0;
+out:
+ fatent_brelse(&fatent);
+ return nr;
}
static int fat_bmap_cluster(struct inode *inode, int cluster)
int cluster, offset;
*phys = 0;
- if ((sbi->fat_bits != 32) &&
- (inode->i_ino == MSDOS_ROOT_INO || (S_ISDIR(inode->i_mode) &&
- !MSDOS_I(inode)->i_start))) {
+ if ((sbi->fat_bits != 32) && (inode->i_ino == MSDOS_ROOT_INO)) {
if (sector < (sbi->dir_entries >> sbi->dir_per_block_bits))
*phys = sector + sbi->dir_start;
return 0;
git://git.onelab.eu / linux-2.6.git / blobdiff