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/*
* QNX4 file system, Linux implementation.
*
* Version : 0.2.1
*
* Using parts of the xiafs filesystem.
*
* History :
*
* 01-06-1998 by Richard Frowijn : first release.
* 20-06-1998 by Frank Denis : Linux 2.1.99+ support, boot signature, misc.
* 30-06-1998 by Frank Denis : first step to write inodes.
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/qnx4_fs.h>
#include <linux/fs.h>
#include <linux/locks.h>
#include <linux/init.h>
#include <linux/highuid.h>
#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#define QNX4_VERSION 4
#define QNX4_BMNAME ".bitmap"
static struct super_operations qnx4_sops;
#ifdef CONFIG_QNX4FS_RW
int qnx4_sync_inode(struct inode *inode)
{
int err = 0;
# if 0
struct buffer_head *bh;
bh = qnx4_update_inode(inode);
if (bh && buffer_dirty(bh))
{
ll_rw_block(WRITE, 1, &bh);
wait_on_buffer(bh);
if (buffer_req(bh) && !buffer_uptodate(bh))
{
printk ("IO error syncing qnx4 inode [%s:%08lx]\n",
kdevname(inode->i_dev), inode->i_ino);
err = -1;
}
brelse (bh);
} else if (!bh) {
err = -1;
}
# endif
return err;
}
static void qnx4_delete_inode(struct inode *inode)
{
QNX4DEBUG(("qnx4: deleting inode [%lu]\n", (unsigned long) inode->i_ino));
lock_kernel();
inode->i_size = 0;
qnx4_truncate(inode);
qnx4_free_inode(inode);
unlock_kernel();
}
static void qnx4_write_super(struct super_block *sb)
{
QNX4DEBUG(("qnx4: write_super\n"));
sb->s_dirt = 0;
}
static void qnx4_write_inode(struct inode *inode, int unused)
{
struct qnx4_inode_entry *raw_inode;
int block, ino;
struct buffer_head *bh;
ino = inode->i_ino;
QNX4DEBUG(("qnx4: write inode 1.\n"));
if (inode->i_nlink == 0) {
return;
}
if (!ino) {
printk("qnx4: bad inode number on dev %s: %d is out of range\n",
kdevname(inode->i_dev), ino);
return;
}
QNX4DEBUG(("qnx4: write inode 2.\n"));
block = ino / QNX4_INODES_PER_BLOCK;
lock_kernel();
if (!(bh = sb_bread(inode->i_sb, block))) {
printk("qnx4: major problem: unable to read inode from dev "
"%s\n", kdevname(inode->i_dev));
unlock_kernel();
return;
}
raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
(ino % QNX4_INODES_PER_BLOCK);
raw_inode->di_mode = cpu_to_le16(inode->i_mode);
raw_inode->di_uid = cpu_to_le16(fs_high2lowuid(inode->i_uid));
raw_inode->di_gid = cpu_to_le16(fs_high2lowgid(inode->i_gid));
raw_inode->di_nlink = cpu_to_le16(inode->i_nlink);
raw_inode->di_size = cpu_to_le32(inode->i_size);
raw_inode->di_mtime = cpu_to_le32(inode->i_mtime);
raw_inode->di_atime = cpu_to_le32(inode->i_atime);
raw_inode->di_ctime = cpu_to_le32(inode->i_ctime);
raw_inode->di_first_xtnt.xtnt_size = cpu_to_le32(inode->i_blocks);
mark_buffer_dirty(bh);
brelse(bh);
unlock_kernel();
}
#endif
static struct super_block *qnx4_read_super(struct super_block *, void *, int);
static void qnx4_put_super(struct super_block *sb);
static void qnx4_read_inode(struct inode *);
static int qnx4_remount(struct super_block *sb, int *flags, char *data);
static int qnx4_statfs(struct super_block *, struct statfs *);
static struct super_operations qnx4_sops =
{
read_inode: qnx4_read_inode,
#ifdef CONFIG_QNX4FS_RW
write_inode: qnx4_write_inode,
delete_inode: qnx4_delete_inode,
#endif
put_super: qnx4_put_super,
#ifdef CONFIG_QNX4FS_RW
write_super: qnx4_write_super,
#endif
statfs: qnx4_statfs,
remount_fs: qnx4_remount,
};
static int qnx4_remount(struct super_block *sb, int *flags, char *data)
{
struct qnx4_sb_info *qs;
qs = &sb->u.qnx4_sb;
qs->Version = QNX4_VERSION;
if (*flags & MS_RDONLY) {
return 0;
}
mark_buffer_dirty(qs->sb_buf);
return 0;
}
struct buffer_head *qnx4_getblk(struct inode *inode, int nr,
int create)
{
struct buffer_head *result = NULL;
if ( nr >= 0 )
nr = qnx4_block_map( inode, nr );
if (nr) {
result = sb_getblk(inode->i_sb, nr);
return result;
}
if (!create) {
return NULL;
}
#if 0
tmp = qnx4_new_block(inode->i_sb);
if (!tmp) {
return NULL;
}
result = sb_getblk(inode->i_sb, tmp);
if (tst) {
qnx4_free_block(inode->i_sb, tmp);
brelse(result);
goto repeat;
}
tst = tmp;
#endif
inode->i_ctime = CURRENT_TIME;
mark_inode_dirty(inode);
return result;
}
struct buffer_head *qnx4_bread(struct inode *inode, int block, int create)
{
struct buffer_head *bh;
bh = qnx4_getblk(inode, block, create);
if (!bh || buffer_uptodate(bh)) {
return bh;
}
ll_rw_block(READ, 1, &bh);
wait_on_buffer(bh);
if (buffer_uptodate(bh)) {
return bh;
}
brelse(bh);
return NULL;
}
int qnx4_get_block( struct inode *inode, long iblock, struct buffer_head *bh, int create )
{
unsigned long phys;
QNX4DEBUG(("qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock));
phys = qnx4_block_map( inode, iblock );
if ( phys ) {
// logical block is before EOF
bh->b_dev = inode->i_dev;
bh->b_blocknr = phys;
bh->b_state |= (1UL << BH_Mapped);
} else if ( create ) {
// to be done.
}
return 0;
}
unsigned long qnx4_block_map( struct inode *inode, long iblock )
{
int ix;
long offset, i_xblk;
unsigned long block = 0;
struct buffer_head *bh = 0;
struct qnx4_xblk *xblk = 0;
struct qnx4_inode_info *qnx4_inode = &inode->u.qnx4_i;
qnx4_nxtnt_t nxtnt = le16_to_cpu(qnx4_inode->i_num_xtnts);
if ( iblock < le32_to_cpu(qnx4_inode->i_first_xtnt.xtnt_size) ) {
// iblock is in the first extent. This is easy.
block = le32_to_cpu(qnx4_inode->i_first_xtnt.xtnt_blk) + iblock - 1;
} else {
// iblock is beyond first extent. We have to follow the extent chain.
i_xblk = le32_to_cpu(qnx4_inode->i_xblk);
offset = iblock - le32_to_cpu(qnx4_inode->i_first_xtnt.xtnt_size);
ix = 0;
while ( --nxtnt > 0 ) {
if ( ix == 0 ) {
// read next xtnt block.
bh = sb_bread(inode->i_sb, i_xblk - 1);
if ( !bh ) {
QNX4DEBUG(("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(("qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
return -EIO;
}
}
if ( offset < le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size) ) {
// got it!
block = le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_blk) + offset - 1;
break;
}
offset -= le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size);
if ( ++ix >= xblk->xblk_num_xtnts ) {
i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
ix = 0;
brelse( bh );
bh = 0;
}
}
if ( bh )
brelse( bh );
}
QNX4DEBUG(("qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
return block;
}
static int qnx4_statfs(struct super_block *sb, struct statfs *buf)
{
buf->f_type = sb->s_magic;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = le32_to_cpu(sb->u.qnx4_sb.BitMap->di_size) * 8;
buf->f_bfree = qnx4_count_free_blocks(sb);
buf->f_bavail = buf->f_bfree;
buf->f_namelen = QNX4_NAME_MAX;
return 0;
}
/*
* Check the root directory of the filesystem to make sure
* it really _is_ a qnx4 filesystem, and to check the size
* of the directory entry.
*/
static const char *qnx4_checkroot(struct super_block *sb)
{
struct buffer_head *bh;
struct qnx4_inode_entry *rootdir;
int rd, rl;
int i, j;
int found = 0;
if (*(sb->u.qnx4_sb.sb->RootDir.di_fname) != '/') {
return "no qnx4 filesystem (no root dir).";
} else {
QNX4DEBUG(("QNX4 filesystem found on dev %s.\n", kdevname(sb->s_dev)));
rd = le32_to_cpu(sb->u.qnx4_sb.sb->RootDir.di_first_xtnt.xtnt_blk) - 1;
rl = le32_to_cpu(sb->u.qnx4_sb.sb->RootDir.di_first_xtnt.xtnt_size);
for (j = 0; j < rl; j++) {
bh = sb_bread(sb, rd + j); /* root dir, first block */
if (bh == NULL) {
return "unable to read root entry.";
}
for (i = 0; i < QNX4_INODES_PER_BLOCK; i++) {
rootdir = (struct qnx4_inode_entry *) (bh->b_data + i * QNX4_DIR_ENTRY_SIZE);
if (rootdir->di_fname != NULL) {
QNX4DEBUG(("Rootdir entry found : [%s]\n", rootdir->di_fname));
if (!strncmp(rootdir->di_fname, QNX4_BMNAME, sizeof QNX4_BMNAME)) {
found = 1;
sb->u.qnx4_sb.BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL );
if (!sb->u.qnx4_sb.BitMap) {
brelse (bh);
return "not enough memory for bitmap inode";
}
memcpy( sb->u.qnx4_sb.BitMap, rootdir, sizeof( struct qnx4_inode_entry ) ); /* keep bitmap inode known */
break;
}
}
}
brelse(bh);
if (found != 0) {
break;
}
}
if (found == 0) {
return "bitmap file not found.";
}
}
return NULL;
}
static struct super_block *qnx4_read_super(struct super_block *s,
void *data, int silent)
{
struct buffer_head *bh;
kdev_t dev = s->s_dev;
struct inode *root;
const char *errmsg;
set_blocksize(dev, QNX4_BLOCK_SIZE);
s->s_blocksize = QNX4_BLOCK_SIZE;
s->s_blocksize_bits = QNX4_BLOCK_SIZE_BITS;
/* Check the boot signature. Since the qnx4 code is
dangerous, we should leave as quickly as possible
if we don't belong here... */
bh = sb_bread(s, 0);
if (!bh) {
printk("qnx4: unable to read the boot sector\n");
goto outnobh;
}
if ( memcmp( (char*)bh->b_data + 4, "QNX4FS", 6 ) ) {
if (!silent)
printk("qnx4: wrong fsid in boot sector.\n");
goto out;
}
brelse(bh);
bh = sb_bread(s, 1);
if (!bh) {
printk("qnx4: unable to read the superblock\n");
goto outnobh;
}
s->s_op = &qnx4_sops;
s->s_magic = QNX4_SUPER_MAGIC;
#ifndef CONFIG_QNX4FS_RW
s->s_flags |= MS_RDONLY; /* Yup, read-only yet */
#endif
s->u.qnx4_sb.sb_buf = bh;
s->u.qnx4_sb.sb = (struct qnx4_super_block *) bh->b_data;
/* check before allocating dentries, inodes, .. */
errmsg = qnx4_checkroot(s);
if (errmsg != NULL) {
if (!silent)
printk("qnx4: %s\n", errmsg);
goto out;
}
/* does root not have inode number QNX4_ROOT_INO ?? */
root = iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
if (!root) {
printk("qnx4: get inode failed\n");
goto out;
}
s->s_root = d_alloc_root(root);
if (s->s_root == NULL)
goto outi;
brelse(bh);
return s;
outi:
iput(root);
out:
brelse(bh);
outnobh:
return NULL;
}
static void qnx4_put_super(struct super_block *sb)
{
kfree( sb->u.qnx4_sb.BitMap );
return;
}
static int qnx4_writepage(struct page *page)
{
return block_write_full_page(page,qnx4_get_block);
}
static int qnx4_readpage(struct file *file, struct page *page)
{
return block_read_full_page(page,qnx4_get_block);
}
static int qnx4_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
{
return cont_prepare_write(page,from,to,qnx4_get_block,
&page->mapping->host->u.qnx4_i.mmu_private);
}
static int qnx4_bmap(struct address_space *mapping, long block)
{
return generic_block_bmap(mapping,block,qnx4_get_block);
}
struct address_space_operations qnx4_aops = {
readpage: qnx4_readpage,
writepage: qnx4_writepage,
sync_page: block_sync_page,
prepare_write: qnx4_prepare_write,
commit_write: generic_commit_write,
bmap: qnx4_bmap
};
static void qnx4_read_inode(struct inode *inode)
{
struct buffer_head *bh;
struct qnx4_inode_entry *raw_inode;
int block, ino;
ino = inode->i_ino;
inode->i_mode = 0;
QNX4DEBUG(("Reading inode : [%d]\n", ino));
if (!ino) {
printk("qnx4: bad inode number on dev %s: %d is out of range\n",
kdevname(inode->i_dev), ino);
return;
}
block = ino / QNX4_INODES_PER_BLOCK;
if (!(bh = sb_bread(inode->i_sb, block))) {
printk("qnx4: major problem: unable to read inode from dev "
"%s\n", kdevname(inode->i_dev));
return;
}
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 = le32_to_cpu(raw_inode->di_mtime);
inode->i_atime = le32_to_cpu(raw_inode->di_atime);
inode->i_ctime = le32_to_cpu(raw_inode->di_ctime);
inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size);
inode->i_blksize = QNX4_DIR_ENTRY_SIZE;
memcpy(&inode->u.qnx4_i, (struct qnx4_inode_info *) raw_inode, QNX4_DIR_ENTRY_SIZE);
if (S_ISREG(inode->i_mode)) {
inode->i_op = &qnx4_file_inode_operations;
inode->i_fop = &qnx4_file_operations;
inode->i_mapping->a_ops = &qnx4_aops;
inode->u.qnx4_i.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;
inode->u.qnx4_i.mmu_private = inode->i_size;
} else
printk("qnx4: bad inode %d on dev %s\n",ino,kdevname(inode->i_dev));
brelse(bh);
}
static DECLARE_FSTYPE_DEV(qnx4_fs_type, "qnx4", qnx4_read_super);
static int __init init_qnx4_fs(void)
{
printk("QNX4 filesystem 0.2.2 registered.\n");
return register_filesystem(&qnx4_fs_type);
}
static void __exit exit_qnx4_fs(void)
{
unregister_filesystem(&qnx4_fs_type);
}
EXPORT_NO_SYMBOLS;
module_init(init_qnx4_fs)
module_exit(exit_qnx4_fs)
MODULE_LICENSE("GPL");
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