unsigned long qnx4_block_map( struct inode *inode, long iblock )
{
int ix;
long i_xblk;
struct buffer_head *bh = NULL;
struct qnx4_xblk *xblk = NULL;
struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts);
u32 offset = iblock;
u32 block = try_extent(&qnx4_inode->di_first_xtnt, &offset);
if (block) {
// iblock is in the first extent. This is easy.
} else {
// iblock is beyond first extent. We have to follow the extent chain.
i_xblk = le32_to_cpu(qnx4_inode->di_xblk);
ix = 0;
while ( --nxtnt > 0 ) {
if ( ix == 0 ) {
// read next xtnt block.
bh = sb_bread(inode->i_sb, i_xblk - 1);
if ( !bh ) {
QNX4DEBUG((KERN_ERR "qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1));
return -EIO;
}
xblk = (struct qnx4_xblk*)bh->b_data;
if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) {
QNX4DEBUG((KERN_ERR "qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
return -EIO;
}
}
block = try_extent(&xblk->xblk_xtnts[ix], &offset);
if (block) {
// got it!
break;
}
if ( ++ix >= xblk->xblk_num_xtnts ) {
i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
ix = 0;
brelse( bh );
bh = NULL;
}
}
if ( bh )
brelse( bh );
}
QNX4DEBUG((KERN_INFO "qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
return block;
}
struct inode *qnx4_iget(struct super_block *sb, unsigned long ino)
{
struct buffer_head *bh;
struct qnx4_inode_entry *raw_inode;
int block;
struct qnx4_inode_entry *qnx4_inode;
struct inode *inode;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
qnx4_inode = qnx4_raw_inode(inode);
inode->i_mode = 0;
QNX4DEBUG((KERN_INFO "reading inode : [%d]\n", ino));
if (!ino) {
printk(KERN_ERR "qnx4: bad inode number on dev %s: %lu is "
"out of range\n",
sb->s_id, ino);
iget_failed(inode);
return ERR_PTR(-EIO);
}
block = ino / QNX4_INODES_PER_BLOCK;
if (!(bh = sb_bread(sb, block))) {
printk(KERN_ERR "qnx4: major problem: unable to read inode from dev "
"%s\n", sb->s_id);
iget_failed(inode);
return ERR_PTR(-EIO);
}
raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
(ino % QNX4_INODES_PER_BLOCK);
inode->i_mode = le16_to_cpu(raw_inode->di_mode);
inode->i_uid = (uid_t)le16_to_cpu(raw_inode->di_uid);
inode->i_gid = (gid_t)le16_to_cpu(raw_inode->di_gid);
inode->i_nlink = le16_to_cpu(raw_inode->di_nlink);
inode->i_size = le32_to_cpu(raw_inode->di_size);
inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->di_mtime);
inode->i_mtime.tv_nsec = 0;
inode->i_atime.tv_sec = le32_to_cpu(raw_inode->di_atime);
inode->i_atime.tv_nsec = 0;
inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->di_ctime);
inode->i_ctime.tv_nsec = 0;
inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size);
memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE);
if (S_ISREG(inode->i_mode)) {
inode->i_fop = &generic_ro_fops;
inode->i_mapping->a_ops = &qnx4_aops;
qnx4_i(inode)->mmu_private = inode->i_size;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = &qnx4_dir_inode_operations;
inode->i_fop = &qnx4_dir_operations;
} else if (S_ISLNK(inode->i_mode)) {
inode->i_op = &page_symlink_inode_operations;
inode->i_mapping->a_ops = &qnx4_aops;
qnx4_i(inode)->mmu_private = inode->i_size;
} else {
printk(KERN_ERR "qnx4: bad inode %lu on dev %s\n",
ino, sb->s_id);
iget_failed(inode);
brelse(bh);
return ERR_PTR(-EIO);
}
brelse(bh);
unlock_new_inode(inode);
return inode;
}
