initial_commit

8 files changed, 858 insertions, 0 deletions

diff --git a/fs/qnx4/Kconfig b/fs/qnx4/Kconfig
new file mode 100644
index 00000000..5f608999
--- /dev/null
+++ b/fs/qnx4/Kconfig
@@ -0,0 +1,14 @@
+config QNX4FS_FS
+	tristate "QNX4 file system support (read only)"
+	depends on BLOCK
+	help
+	  This is the file system used by the real-time operating systems
+	  QNX 4 and QNX 6 (the latter is also called QNX RTP).
+	  Further information is available at <http://www.qnx.com/>.
+	  Say Y if you intend to mount QNX hard disks or floppies.
+
+	  To compile this file system support as a module, choose M here: the
+	  module will be called qnx4.
+
+	  If you don't know whether you need it, then you don't need it:
+	  answer N.
diff --git a/fs/qnx4/Makefile b/fs/qnx4/Makefile
new file mode 100644
index 00000000..4a283b3f
--- /dev/null
+++ b/fs/qnx4/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the linux qnx4-filesystem routines.
+#
+
+obj-$(CONFIG_QNX4FS_FS) += qnx4.o
+
+qnx4-objs := inode.o dir.o namei.o bitmap.o
diff --git a/fs/qnx4/README b/fs/qnx4/README
new file mode 100644
index 00000000..1f1e320d
--- /dev/null
+++ b/fs/qnx4/README
@@ -0,0 +1,9 @@
+
+  This is a snapshot of the QNX4 filesystem for Linux.
+  Please send diffs and remarks to <al@alarsen.net> .
+  
+Credits :
+
+Richard "Scuba" A. Frowijn     <scuba@wxs.nl>
+Frank "Jedi/Sector One" Denis  <j@pureftpd.org>
+Anders Larsen                  <al@alarsen.net> (Maintainer)
diff --git a/fs/qnx4/bitmap.c b/fs/qnx4/bitmap.c
new file mode 100644
index 00000000..22e0d60e
--- /dev/null
+++ b/fs/qnx4/bitmap.c
@@ -0,0 +1,58 @@
+/*
+ * QNX4 file system, Linux implementation.
+ *
+ * Version : 0.2.1
+ *
+ * Using parts of the xiafs filesystem.
+ *
+ * History :
+ *
+ * 28-05-1998 by Richard Frowijn : first release.
+ * 20-06-1998 by Frank Denis : basic optimisations.
+ * 25-06-1998 by Frank Denis : qnx4_is_free, qnx4_set_bitmap, qnx4_bmap .
+ * 28-06-1998 by Frank Denis : qnx4_free_inode (to be fixed) .
+ */
+
+#include <linux/buffer_head.h>
+#include <linux/bitops.h>
+#include "qnx4.h"
+
+static void count_bits(register const char *bmPart, register int size,
+		       int *const tf)
+{
+	char b;
+	int tot = *tf;
+
+	if (size > QNX4_BLOCK_SIZE) {
+		size = QNX4_BLOCK_SIZE;
+	}
+	do {
+		b = *bmPart++;
+		tot += 8 - hweight8(b);
+		size--;
+	} while (size != 0);
+	*tf = tot;
+}
+
+unsigned long qnx4_count_free_blocks(struct super_block *sb)
+{
+	int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
+	int total = 0;
+	int total_free = 0;
+	int offset = 0;
+	int size = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size);
+	struct buffer_head *bh;
+
+	while (total < size) {
+		if ((bh = sb_bread(sb, start + offset)) == NULL) {
+			printk(KERN_ERR "qnx4: I/O error in counting free blocks\n");
+			break;
+		}
+		count_bits(bh->b_data, size - total, &total_free);
+		brelse(bh);
+		total += QNX4_BLOCK_SIZE;
+		offset++;
+	}
+
+	return total_free;
+}
diff --git a/fs/qnx4/dir.c b/fs/qnx4/dir.c
new file mode 100644
index 00000000..7b032946
--- /dev/null
+++ b/fs/qnx4/dir.c
@@ -0,0 +1,85 @@
+/*
+ * QNX4 file system, Linux implementation.
+ *
+ * Version : 0.2.1
+ *
+ * Using parts of the xiafs filesystem.
+ *
+ * History :
+ *
+ * 28-05-1998 by Richard Frowijn : first release.
+ * 20-06-1998 by Frank Denis : Linux 2.1.99+ & dcache support.
+ */
+
+#include <linux/buffer_head.h>
+#include "qnx4.h"
+
+static int qnx4_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+	struct inode *inode = filp->f_path.dentry->d_inode;
+	unsigned int offset;
+	struct buffer_head *bh;
+	struct qnx4_inode_entry *de;
+	struct qnx4_link_info *le;
+	unsigned long blknum;
+	int ix, ino;
+	int size;
+
+	QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
+	QNX4DEBUG((KERN_INFO "filp->f_pos         = %ld\n", (long) filp->f_pos));
+
+	while (filp->f_pos < inode->i_size) {
+		blknum = qnx4_block_map( inode, filp->f_pos >> QNX4_BLOCK_SIZE_BITS );
+		bh = sb_bread(inode->i_sb, blknum);
+		if(bh==NULL) {
+			printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
+			break;
+		}
+		ix = (int)(filp->f_pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
+		while (ix < QNX4_INODES_PER_BLOCK) {
+			offset = ix * QNX4_DIR_ENTRY_SIZE;
+			de = (struct qnx4_inode_entry *) (bh->b_data + offset);
+			size = strlen(de->di_fname);
+			if (size) {
+				if ( !( de->di_status & QNX4_FILE_LINK ) && size > QNX4_SHORT_NAME_MAX )
+					size = QNX4_SHORT_NAME_MAX;
+				else if ( size > QNX4_NAME_MAX )
+					size = QNX4_NAME_MAX;
+
+				if ( ( de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK) ) != 0 ) {
+					QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, de->di_fname));
+					if ( ( de->di_status & QNX4_FILE_LINK ) == 0 )
+						ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
+					else {
+						le  = (struct qnx4_link_info*)de;
+						ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
+							QNX4_INODES_PER_BLOCK +
+							le->dl_inode_ndx;
+					}
+					if (filldir(dirent, de->di_fname, size, filp->f_pos, ino, DT_UNKNOWN) < 0) {
+						brelse(bh);
+						goto out;
+					}
+				}
+			}
+			ix++;
+			filp->f_pos += QNX4_DIR_ENTRY_SIZE;
+		}
+		brelse(bh);
+	}
+out:
+	return 0;
+}
+
+const struct file_operations qnx4_dir_operations =
+{
+	.llseek		= generic_file_llseek,
+	.read		= generic_read_dir,
+	.readdir	= qnx4_readdir,
+	.fsync		= generic_file_fsync,
+};
+
+const struct inode_operations qnx4_dir_inode_operations =
+{
+	.lookup		= qnx4_lookup,
+};
diff --git a/fs/qnx4/inode.c b/fs/qnx4/inode.c
new file mode 100644
index 00000000..2b064661
--- /dev/null
+++ b/fs/qnx4/inode.c
@@ -0,0 +1,504 @@
+/*
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/highuid.h>
+#include <linux/pagemap.h>
+#include <linux/buffer_head.h>
+#include <linux/writeback.h>
+#include <linux/statfs.h>
+#include "qnx4.h"
+
+#define QNX4_VERSION  4
+#define QNX4_BMNAME   ".bitmap"
+
+static const struct super_operations qnx4_sops;
+
+static void qnx4_put_super(struct super_block *sb);
+static struct inode *qnx4_alloc_inode(struct super_block *sb);
+static void qnx4_destroy_inode(struct inode *inode);
+static int qnx4_remount(struct super_block *sb, int *flags, char *data);
+static int qnx4_statfs(struct dentry *, struct kstatfs *);
+
+static const struct super_operations qnx4_sops =
+{
+	.alloc_inode	= qnx4_alloc_inode,
+	.destroy_inode	= qnx4_destroy_inode,
+	.put_super	= qnx4_put_super,
+	.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 = qnx4_sb(sb);
+	qs->Version = QNX4_VERSION;
+	*flags |= MS_RDONLY;
+	return 0;
+}
+
+static 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;
+	}
+	return NULL;
+}
+
+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;
+}
+
+static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create )
+{
+	unsigned long phys;
+
+	QNX4DEBUG((KERN_INFO "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
+		map_bh(bh, inode->i_sb, phys);
+	}
+	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 = 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);
+
+	if ( iblock < le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size) ) {
+		// iblock is in the first extent. This is easy.
+		block = le32_to_cpu(qnx4_inode->di_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->di_xblk);
+		offset = iblock - le32_to_cpu(qnx4_inode->di_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((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;
+				}
+			}
+			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 = NULL;
+			}
+		}
+		if ( bh )
+			brelse( bh );
+	}
+
+	QNX4DEBUG((KERN_INFO "qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
+	return block;
+}
+
+static int qnx4_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *sb = dentry->d_sb;
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
+
+	buf->f_type    = sb->s_magic;
+	buf->f_bsize   = sb->s_blocksize;
+	buf->f_blocks  = le32_to_cpu(qnx4_sb(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;
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
+
+	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 (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/') {
+		return "no qnx4 filesystem (no root dir).";
+	} else {
+		QNX4DEBUG((KERN_NOTICE "QNX4 filesystem found on dev %s.\n", sb->s_id));
+		rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1;
+		rl = le32_to_cpu(qnx4_sb(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((KERN_INFO "rootdir entry found : [%s]\n", rootdir->di_fname));
+					if (!strcmp(rootdir->di_fname,
+						    QNX4_BMNAME)) {
+						found = 1;
+						qnx4_sb(sb)->BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL );
+						if (!qnx4_sb(sb)->BitMap) {
+							brelse (bh);
+							return "not enough memory for bitmap inode";
+						}
+						memcpy( qnx4_sb(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 int qnx4_fill_super(struct super_block *s, void *data, int silent)
+{
+	struct buffer_head *bh;
+	struct inode *root;
+	const char *errmsg;
+	struct qnx4_sb_info *qs;
+	int ret = -EINVAL;
+
+	qs = kzalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL);
+	if (!qs)
+		return -ENOMEM;
+	s->s_fs_info = qs;
+
+	sb_set_blocksize(s, QNX4_BLOCK_SIZE);
+
+	/* Check the superblock signature. Since the qnx4 code is
+	   dangerous, we should leave as quickly as possible
+	   if we don't belong here... */
+	bh = sb_bread(s, 1);
+	if (!bh) {
+		printk(KERN_ERR "qnx4: unable to read the superblock\n");
+		goto outnobh;
+	}
+	if ( le32_to_cpup((__le32*) bh->b_data) != QNX4_SUPER_MAGIC ) {
+		if (!silent)
+			printk(KERN_ERR "qnx4: wrong fsid in superblock.\n");
+		goto out;
+	}
+	s->s_op = &qnx4_sops;
+	s->s_magic = QNX4_SUPER_MAGIC;
+	s->s_flags |= MS_RDONLY;	/* Yup, read-only yet */
+	qnx4_sb(s)->sb_buf = bh;
+	qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data;
+
+
+ 	/* check before allocating dentries, inodes, .. */
+	errmsg = qnx4_checkroot(s);
+	if (errmsg != NULL) {
+ 		if (!silent)
+			printk(KERN_ERR "qnx4: %s\n", errmsg);
+		goto out;
+	}
+
+ 	/* does root not have inode number QNX4_ROOT_INO ?? */
+	root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
+	if (IS_ERR(root)) {
+		printk(KERN_ERR "qnx4: get inode failed\n");
+		ret = PTR_ERR(root);
+ 		goto out;
+ 	}
+
+	ret = -ENOMEM;
+ 	s->s_root = d_alloc_root(root);
+ 	if (s->s_root == NULL)
+ 		goto outi;
+
+	brelse(bh);
+	return 0;
+
+      outi:
+	iput(root);
+      out:
+	brelse(bh);
+      outnobh:
+	kfree(qs);
+	s->s_fs_info = NULL;
+	return ret;
+}
+
+static void qnx4_put_super(struct super_block *sb)
+{
+	struct qnx4_sb_info *qs = qnx4_sb(sb);
+	kfree( qs->BitMap );
+	kfree( qs );
+	sb->s_fs_info = NULL;
+	return;
+}
+
+static int qnx4_writepage(struct page *page, struct writeback_control *wbc)
+{
+	return block_write_full_page(page,qnx4_get_block, wbc);
+}
+
+static int qnx4_readpage(struct file *file, struct page *page)
+{
+	return block_read_full_page(page,qnx4_get_block);
+}
+
+static int qnx4_write_begin(struct file *file, struct address_space *mapping,
+			loff_t pos, unsigned len, unsigned flags,
+			struct page **pagep, void **fsdata)
+{
+	struct qnx4_inode_info *qnx4_inode = qnx4_i(mapping->host);
+	int ret;
+
+	*pagep = NULL;
+	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
+				qnx4_get_block,
+				&qnx4_inode->mmu_private);
+	if (unlikely(ret)) {
+		loff_t isize = mapping->host->i_size;
+		if (pos + len > isize)
+			vmtruncate(mapping->host, isize);
+	}
+
+	return ret;
+}
+static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
+{
+	return generic_block_bmap(mapping,block,qnx4_get_block);
+}
+static const struct address_space_operations qnx4_aops = {
+	.readpage	= qnx4_readpage,
+	.writepage	= qnx4_writepage,
+	.write_begin	= qnx4_write_begin,
+	.write_end	= generic_write_end,
+	.bmap		= qnx4_bmap
+};
+
+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;
+}
+
+static struct kmem_cache *qnx4_inode_cachep;
+
+static struct inode *qnx4_alloc_inode(struct super_block *sb)
+{
+	struct qnx4_inode_info *ei;
+	ei = kmem_cache_alloc(qnx4_inode_cachep, GFP_KERNEL);
+	if (!ei)
+		return NULL;
+	return &ei->vfs_inode;
+}
+
+static void qnx4_i_callback(struct rcu_head *head)
+{
+	struct inode *inode = container_of(head, struct inode, i_rcu);
+	INIT_LIST_HEAD(&inode->i_dentry);
+	kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
+}
+
+static void qnx4_destroy_inode(struct inode *inode)
+{
+	call_rcu(&inode->i_rcu, qnx4_i_callback);
+}
+
+static void init_once(void *foo)
+{
+	struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo;
+
+	inode_init_once(&ei->vfs_inode);
+}
+
+static int init_inodecache(void)
+{
+	qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache",
+					     sizeof(struct qnx4_inode_info),
+					     0, (SLAB_RECLAIM_ACCOUNT|
+						SLAB_MEM_SPREAD),
+					     init_once);
+	if (qnx4_inode_cachep == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+static void destroy_inodecache(void)
+{
+	kmem_cache_destroy(qnx4_inode_cachep);
+}
+
+static struct dentry *qnx4_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
+{
+	return mount_bdev(fs_type, flags, dev_name, data, qnx4_fill_super);
+}
+
+static struct file_system_type qnx4_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "qnx4",
+	.mount		= qnx4_mount,
+	.kill_sb	= kill_block_super,
+	.fs_flags	= FS_REQUIRES_DEV,
+};
+
+static int __init init_qnx4_fs(void)
+{
+	int err;
+
+	err = init_inodecache();
+	if (err)
+		return err;
+
+	err = register_filesystem(&qnx4_fs_type);
+	if (err) {
+		destroy_inodecache();
+		return err;
+	}
+
+	printk(KERN_INFO "QNX4 filesystem 0.2.3 registered.\n");
+	return 0;
+}
+
+static void __exit exit_qnx4_fs(void)
+{
+	unregister_filesystem(&qnx4_fs_type);
+	destroy_inodecache();
+}
+
+module_init(init_qnx4_fs)
+module_exit(exit_qnx4_fs)
+MODULE_LICENSE("GPL");
+
diff --git a/fs/qnx4/namei.c b/fs/qnx4/namei.c
new file mode 100644
index 00000000..275327b5
--- /dev/null
+++ b/fs/qnx4/namei.c
@@ -0,0 +1,132 @@
+/* 
+ * QNX4 file system, Linux implementation.
+ * 
+ * Version : 0.2.1
+ * 
+ * Using parts of the xiafs filesystem.
+ * 
+ * History :
+ * 
+ * 01-06-1998 by Richard Frowijn : first release.
+ * 21-06-1998 by Frank Denis : dcache support, fixed error codes.
+ * 04-07-1998 by Frank Denis : first step for rmdir/unlink.
+ */
+
+#include <linux/buffer_head.h>
+#include "qnx4.h"
+
+
+/*
+ * check if the filename is correct. For some obscure reason, qnx writes a
+ * new file twice in the directory entry, first with all possible options at 0
+ * and for a second time the way it is, they want us not to access the qnx
+ * filesystem when whe are using linux.
+ */
+static int qnx4_match(int len, const char *name,
+		      struct buffer_head *bh, unsigned long *offset)
+{
+	struct qnx4_inode_entry *de;
+	int namelen, thislen;
+
+	if (bh == NULL) {
+		printk(KERN_WARNING "qnx4: matching unassigned buffer !\n");
+		return 0;
+	}
+	de = (struct qnx4_inode_entry *) (bh->b_data + *offset);
+	*offset += QNX4_DIR_ENTRY_SIZE;
+	if ((de->di_status & QNX4_FILE_LINK) != 0) {
+		namelen = QNX4_NAME_MAX;
+	} else {
+		namelen = QNX4_SHORT_NAME_MAX;
+	}
+	/* "" means "." ---> so paths like "/usr/lib//libc.a" work */
+	if (!len && (de->di_fname[0] == '.') && (de->di_fname[1] == '\0')) {
+		return 1;
+	}
+	thislen = strlen( de->di_fname );
+	if ( thislen > namelen )
+		thislen = namelen;
+	if (len != thislen) {
+		return 0;
+	}
+	if (strncmp(name, de->di_fname, len) == 0) {
+		if ((de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)) != 0) {
+			return 1;
+		}
+	}
+	return 0;
+}
+
+static struct buffer_head *qnx4_find_entry(int len, struct inode *dir,
+	   const char *name, struct qnx4_inode_entry **res_dir, int *ino)
+{
+	unsigned long block, offset, blkofs;
+	struct buffer_head *bh;
+
+	*res_dir = NULL;
+	if (!dir->i_sb) {
+		printk(KERN_WARNING "qnx4: no superblock on dir.\n");
+		return NULL;
+	}
+	bh = NULL;
+	block = offset = blkofs = 0;
+	while (blkofs * QNX4_BLOCK_SIZE + offset < dir->i_size) {
+		if (!bh) {
+			bh = qnx4_bread(dir, blkofs, 0);
+			if (!bh) {
+				blkofs++;
+				continue;
+			}
+		}
+		*res_dir = (struct qnx4_inode_entry *) (bh->b_data + offset);
+		if (qnx4_match(len, name, bh, &offset)) {
+			block = qnx4_block_map( dir, blkofs );
+			*ino = block * QNX4_INODES_PER_BLOCK +
+			    (offset / QNX4_DIR_ENTRY_SIZE) - 1;
+			return bh;
+		}
+		if (offset < bh->b_size) {
+			continue;
+		}
+		brelse(bh);
+		bh = NULL;
+		offset = 0;
+		blkofs++;
+	}
+	brelse(bh);
+	*res_dir = NULL;
+	return NULL;
+}
+
+struct dentry * qnx4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+	int ino;
+	struct qnx4_inode_entry *de;
+	struct qnx4_link_info *lnk;
+	struct buffer_head *bh;
+	const char *name = dentry->d_name.name;
+	int len = dentry->d_name.len;
+	struct inode *foundinode = NULL;
+
+	if (!(bh = qnx4_find_entry(len, dir, name, &de, &ino)))
+		goto out;
+	/* The entry is linked, let's get the real info */
+	if ((de->di_status & QNX4_FILE_LINK) == QNX4_FILE_LINK) {
+		lnk = (struct qnx4_link_info *) de;
+		ino = (le32_to_cpu(lnk->dl_inode_blk) - 1) *
+                    QNX4_INODES_PER_BLOCK +
+		    lnk->dl_inode_ndx;
+	}
+	brelse(bh);
+
+	foundinode = qnx4_iget(dir->i_sb, ino);
+	if (IS_ERR(foundinode)) {
+		QNX4DEBUG((KERN_ERR "qnx4: lookup->iget -> error %ld\n",
+			   PTR_ERR(foundinode)));
+		return ERR_CAST(foundinode);
+	}
+out:
+	d_add(dentry, foundinode);
+
+	return NULL;
+}
diff --git a/fs/qnx4/qnx4.h b/fs/qnx4/qnx4.h
new file mode 100644
index 00000000..33a60858
--- /dev/null
+++ b/fs/qnx4/qnx4.h
@@ -0,0 +1,49 @@
+#include <linux/fs.h>
+#include <linux/qnx4_fs.h>
+
+#define QNX4_DEBUG 0
+
+#if QNX4_DEBUG
+#define QNX4DEBUG(X) printk X
+#else
+#define QNX4DEBUG(X) (void) 0
+#endif
+
+struct qnx4_sb_info {
+	struct buffer_head	*sb_buf;	/* superblock buffer */
+	struct qnx4_super_block	*sb;		/* our superblock */
+	unsigned int		Version;	/* may be useful */
+	struct qnx4_inode_entry	*BitMap;	/* useful */
+};
+
+struct qnx4_inode_info {
+	struct qnx4_inode_entry raw;
+	loff_t mmu_private;
+	struct inode vfs_inode;
+};
+
+extern struct inode *qnx4_iget(struct super_block *, unsigned long);
+extern struct dentry *qnx4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd);
+extern unsigned long qnx4_count_free_blocks(struct super_block *sb);
+extern unsigned long qnx4_block_map(struct inode *inode, long iblock);
+
+extern struct buffer_head *qnx4_bread(struct inode *, int, int);
+
+extern const struct inode_operations qnx4_dir_inode_operations;
+extern const struct file_operations qnx4_dir_operations;
+extern int qnx4_is_free(struct super_block *sb, long block);
+
+static inline struct qnx4_sb_info *qnx4_sb(struct super_block *sb)
+{
+	return sb->s_fs_info;
+}
+
+static inline struct qnx4_inode_info *qnx4_i(struct inode *inode)
+{
+	return container_of(inode, struct qnx4_inode_info, vfs_inode);
+}
+
+static inline struct qnx4_inode_entry *qnx4_raw_inode(struct inode *inode)
+{
+	return &qnx4_i(inode)->raw;
+}