Merge ../torvalds-2.6/

23 files changed, 6088 insertions, 0 deletions

diff --git a/fs/9p/9p.c b/fs/9p/9p.c
new file mode 100644
index 00000000000..e847f504a47
--- /dev/null
+++ b/fs/9p/9p.c
@@ -0,0 +1,359 @@
+/*
+ *  linux/fs/9p/9p.c
+ *
+ *  This file contains functions 9P2000 functions
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "mux.h"
+
+/**
+ * v9fs_t_version - negotiate protocol parameters with sever
+ * @v9ses: 9P2000 session information
+ * @msize: requested max size packet
+ * @version: requested version.extension string
+ * @fcall: pointer to response fcall pointer
+ *
+ */
+
+int
+v9fs_t_version(struct v9fs_session_info *v9ses, u32 msize,
+	       char *version, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "msize: %d version: %s\n", msize, version);
+	msg.id = TVERSION;
+	msg.params.tversion.msize = msize;
+	msg.params.tversion.version = version;
+
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_t_attach - mount the server
+ * @v9ses: 9P2000 session information
+ * @uname: user name doing the attach
+ * @aname: remote name being attached to
+ * @fid: mount fid to attatch to root node
+ * @afid: authentication fid (in this case result key)
+ * @fcall: pointer to response fcall pointer
+ *
+ */
+
+int
+v9fs_t_attach(struct v9fs_session_info *v9ses, char *uname, char *aname,
+	      u32 fid, u32 afid, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "uname '%s' aname '%s' fid %d afid %d\n", uname,
+		aname, fid, afid);
+	msg.id = TATTACH;
+	msg.params.tattach.fid = fid;
+	msg.params.tattach.afid = afid;
+	msg.params.tattach.uname = uname;
+	msg.params.tattach.aname = aname;
+
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_t_clunk - release a fid (finish a transaction)
+ * @v9ses: 9P2000 session information
+ * @fid: fid to release
+ * @fcall: pointer to response fcall pointer
+ *
+ */
+
+int
+v9fs_t_clunk(struct v9fs_session_info *v9ses, u32 fid,
+	     struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "fid %d\n", fid);
+	msg.id = TCLUNK;
+	msg.params.tclunk.fid = fid;
+
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_v9fs_t_flush - flush a pending transaction
+ * @v9ses: 9P2000 session information
+ * @tag: tid to release
+ *
+ */
+
+int v9fs_t_flush(struct v9fs_session_info *v9ses, u16 tag)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "oldtag %d\n", tag);
+	msg.id = TFLUSH;
+	msg.params.tflush.oldtag = tag;
+	return v9fs_mux_rpc(v9ses, &msg, NULL);
+}
+
+/**
+ * v9fs_t_stat - read a file's meta-data
+ * @v9ses: 9P2000 session information
+ * @fid: fid pointing to file or directory to get info about
+ * @fcall: pointer to response fcall
+ *
+ */
+
+int
+v9fs_t_stat(struct v9fs_session_info *v9ses, u32 fid, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "fid %d\n", fid);
+	if (fcall)
+		*fcall = NULL;
+
+	msg.id = TSTAT;
+	msg.params.tstat.fid = fid;
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_t_wstat - write a file's meta-data
+ * @v9ses: 9P2000 session information
+ * @fid: fid pointing to file or directory to write info about
+ * @stat: metadata
+ * @fcall: pointer to response fcall
+ *
+ */
+
+int
+v9fs_t_wstat(struct v9fs_session_info *v9ses, u32 fid,
+	     struct v9fs_stat *stat, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "fid %d length %d\n", fid, (int)stat->length);
+	msg.id = TWSTAT;
+	msg.params.twstat.fid = fid;
+	msg.params.twstat.stat = stat;
+
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_t_walk - walk a fid to a new file or directory
+ * @v9ses: 9P2000 session information
+ * @fid: fid to walk
+ * @newfid: new fid (for clone operations)
+ * @name: path to walk fid to
+ * @fcall: pointer to response fcall
+ *
+ */
+
+/* TODO: support multiple walk */
+
+int
+v9fs_t_walk(struct v9fs_session_info *v9ses, u32 fid, u32 newfid,
+	    char *name, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "fid %d newfid %d wname '%s'\n", fid, newfid, name);
+	msg.id = TWALK;
+	msg.params.twalk.fid = fid;
+	msg.params.twalk.newfid = newfid;
+
+	if (name) {
+		msg.params.twalk.nwname = 1;
+		msg.params.twalk.wnames = &name;
+	} else {
+		msg.params.twalk.nwname = 0;
+	}
+
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_t_open - open a file
+ *
+ * @v9ses - 9P2000 session information
+ * @fid - fid to open
+ * @mode - mode to open file (R, RW, etc)
+ * @fcall - pointer to response fcall
+ *
+ */
+
+int
+v9fs_t_open(struct v9fs_session_info *v9ses, u32 fid, u8 mode,
+	    struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+	long errorno = -1;
+
+	dprintk(DEBUG_9P, "fid %d mode %d\n", fid, mode);
+	msg.id = TOPEN;
+	msg.params.topen.fid = fid;
+	msg.params.topen.mode = mode;
+
+	errorno = v9fs_mux_rpc(v9ses, &msg, fcall);
+
+	return errorno;
+}
+
+/**
+ * v9fs_t_remove - remove a file or directory
+ * @v9ses: 9P2000 session information
+ * @fid: fid to remove
+ * @fcall: pointer to response fcall
+ *
+ */
+
+int
+v9fs_t_remove(struct v9fs_session_info *v9ses, u32 fid,
+	      struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "fid %d\n", fid);
+	msg.id = TREMOVE;
+	msg.params.tremove.fid = fid;
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_t_create - create a file or directory
+ * @v9ses: 9P2000 session information
+ * @fid: fid to create
+ * @name: name of the file or directory to create
+ * @perm: permissions to create with
+ * @mode: mode to open file (R, RW, etc)
+ * @fcall: pointer to response fcall
+ *
+ */
+
+int
+v9fs_t_create(struct v9fs_session_info *v9ses, u32 fid, char *name,
+	      u32 perm, u8 mode, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+
+	dprintk(DEBUG_9P, "fid %d name '%s' perm %x mode %d\n",
+		fid, name, perm, mode);
+
+	msg.id = TCREATE;
+	msg.params.tcreate.fid = fid;
+	msg.params.tcreate.name = name;
+	msg.params.tcreate.perm = perm;
+	msg.params.tcreate.mode = mode;
+
+	return v9fs_mux_rpc(v9ses, &msg, fcall);
+}
+
+/**
+ * v9fs_t_read - read data
+ * @v9ses: 9P2000 session information
+ * @fid: fid to read from
+ * @offset: offset to start read at
+ * @count: how many bytes to read
+ * @fcall: pointer to response fcall (with data)
+ *
+ */
+
+int
+v9fs_t_read(struct v9fs_session_info *v9ses, u32 fid, u64 offset,
+	    u32 count, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+	struct v9fs_fcall *rc = NULL;
+	long errorno = -1;
+
+	dprintk(DEBUG_9P, "fid %d offset 0x%lx count 0x%x\n", fid,
+		(long unsigned int)offset, count);
+	msg.id = TREAD;
+	msg.params.tread.fid = fid;
+	msg.params.tread.offset = offset;
+	msg.params.tread.count = count;
+	errorno = v9fs_mux_rpc(v9ses, &msg, &rc);
+
+	if (!errorno) {
+		errorno = rc->params.rread.count;
+		dump_data(rc->params.rread.data, rc->params.rread.count);
+	}
+
+	if (fcall)
+		*fcall = rc;
+	else
+		kfree(rc);
+
+	return errorno;
+}
+
+/**
+ * v9fs_t_write - write data
+ * @v9ses: 9P2000 session information
+ * @fid: fid to write to
+ * @offset: offset to start write at
+ * @count: how many bytes to write
+ * @fcall: pointer to response fcall
+ *
+ */
+
+int
+v9fs_t_write(struct v9fs_session_info *v9ses, u32 fid,
+	     u64 offset, u32 count, void *data, struct v9fs_fcall **fcall)
+{
+	struct v9fs_fcall msg;
+	struct v9fs_fcall *rc = NULL;
+	long errorno = -1;
+
+	dprintk(DEBUG_9P, "fid %d offset 0x%llx count 0x%x\n", fid,
+		(unsigned long long)offset, count);
+	dump_data(data, count);
+
+	msg.id = TWRITE;
+	msg.params.twrite.fid = fid;
+	msg.params.twrite.offset = offset;
+	msg.params.twrite.count = count;
+	msg.params.twrite.data = data;
+
+	errorno = v9fs_mux_rpc(v9ses, &msg, &rc);
+
+	if (!errorno)
+		errorno = rc->params.rwrite.count;
+
+	if (fcall)
+		*fcall = rc;
+	else
+		kfree(rc);
+
+	return errorno;
+}
diff --git a/fs/9p/9p.h b/fs/9p/9p.h
new file mode 100644
index 00000000000..f55424216be
--- /dev/null
+++ b/fs/9p/9p.h
@@ -0,0 +1,341 @@
+/*
+ * linux/fs/9p/9p.h
+ *
+ * 9P protocol definitions.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+/* Message Types */
+enum {
+	TVERSION = 100,
+	RVERSION,
+	TAUTH = 102,
+	RAUTH,
+	TATTACH = 104,
+	RATTACH,
+	TERROR = 106,
+	RERROR,
+	TFLUSH = 108,
+	RFLUSH,
+	TWALK = 110,
+	RWALK,
+	TOPEN = 112,
+	ROPEN,
+	TCREATE = 114,
+	RCREATE,
+	TREAD = 116,
+	RREAD,
+	TWRITE = 118,
+	RWRITE,
+	TCLUNK = 120,
+	RCLUNK,
+	TREMOVE = 122,
+	RREMOVE,
+	TSTAT = 124,
+	RSTAT,
+	TWSTAT = 126,
+	RWSTAT,
+};
+
+/* modes */
+enum {
+	V9FS_OREAD = 0x00,
+	V9FS_OWRITE = 0x01,
+	V9FS_ORDWR = 0x02,
+	V9FS_OEXEC = 0x03,
+	V9FS_OEXCL = 0x04,
+	V9FS_OTRUNC = 0x10,
+	V9FS_OREXEC = 0x20,
+	V9FS_ORCLOSE = 0x40,
+	V9FS_OAPPEND = 0x80,
+};
+
+/* permissions */
+enum {
+	V9FS_DMDIR = 0x80000000,
+	V9FS_DMAPPEND = 0x40000000,
+	V9FS_DMEXCL = 0x20000000,
+	V9FS_DMMOUNT = 0x10000000,
+	V9FS_DMAUTH = 0x08000000,
+	V9FS_DMTMP = 0x04000000,
+	V9FS_DMSYMLINK = 0x02000000,
+	V9FS_DMLINK = 0x01000000,
+	/* 9P2000.u extensions */
+	V9FS_DMDEVICE = 0x00800000,
+	V9FS_DMNAMEDPIPE = 0x00200000,
+	V9FS_DMSOCKET = 0x00100000,
+	V9FS_DMSETUID = 0x00080000,
+	V9FS_DMSETGID = 0x00040000,
+};
+
+/* qid.types */
+enum {
+	V9FS_QTDIR = 0x80,
+	V9FS_QTAPPEND = 0x40,
+	V9FS_QTEXCL = 0x20,
+	V9FS_QTMOUNT = 0x10,
+	V9FS_QTAUTH = 0x08,
+	V9FS_QTTMP = 0x04,
+	V9FS_QTSYMLINK = 0x02,
+	V9FS_QTLINK = 0x01,
+	V9FS_QTFILE = 0x00,
+};
+
+/* ample room for Twrite/Rread header (iounit) */
+#define V9FS_IOHDRSZ	24
+
+/* qids are the unique ID for a file (like an inode */
+struct v9fs_qid {
+	u8 type;
+	u32 version;
+	u64 path;
+};
+
+/* Plan 9 file metadata (stat) structure */
+struct v9fs_stat {
+	u16 size;
+	u16 type;
+	u32 dev;
+	struct v9fs_qid qid;
+	u32 mode;
+	u32 atime;
+	u32 mtime;
+	u64 length;
+	char *name;
+	char *uid;
+	char *gid;
+	char *muid;
+	char *extension;	/* 9p2000.u extensions */
+	u32 n_uid;		/* 9p2000.u extensions */
+	u32 n_gid;		/* 9p2000.u extensions */
+	u32 n_muid;		/* 9p2000.u extensions */
+	char data[0];
+};
+
+/* Structures for Protocol Operations */
+
+struct Tversion {
+	u32 msize;
+	char *version;
+};
+
+struct Rversion {
+	u32 msize;
+	char *version;
+};
+
+struct Tauth {
+	u32 afid;
+	char *uname;
+	char *aname;
+};
+
+struct Rauth {
+	struct v9fs_qid qid;
+};
+
+struct Rerror {
+	char *error;
+	u32 errno;		/* 9p2000.u extension */
+};
+
+struct Tflush {
+	u32 oldtag;
+};
+
+struct Rflush {
+};
+
+struct Tattach {
+	u32 fid;
+	u32 afid;
+	char *uname;
+	char *aname;
+};
+
+struct Rattach {
+	struct v9fs_qid qid;
+};
+
+struct Twalk {
+	u32 fid;
+	u32 newfid;
+	u32 nwname;
+	char **wnames;
+};
+
+struct Rwalk {
+	u32 nwqid;
+	struct v9fs_qid *wqids;
+};
+
+struct Topen {
+	u32 fid;
+	u8 mode;
+};
+
+struct Ropen {
+	struct v9fs_qid qid;
+	u32 iounit;
+};
+
+struct Tcreate {
+	u32 fid;
+	char *name;
+	u32 perm;
+	u8 mode;
+};
+
+struct Rcreate {
+	struct v9fs_qid qid;
+	u32 iounit;
+};
+
+struct Tread {
+	u32 fid;
+	u64 offset;
+	u32 count;
+};
+
+struct Rread {
+	u32 count;
+	u8 *data;
+};
+
+struct Twrite {
+	u32 fid;
+	u64 offset;
+	u32 count;
+	u8 *data;
+};
+
+struct Rwrite {
+	u32 count;
+};
+
+struct Tclunk {
+	u32 fid;
+};
+
+struct Rclunk {
+};
+
+struct Tremove {
+	u32 fid;
+};
+
+struct Rremove {
+};
+
+struct Tstat {
+	u32 fid;
+};
+
+struct Rstat {
+	struct v9fs_stat *stat;
+};
+
+struct Twstat {
+	u32 fid;
+	struct v9fs_stat *stat;
+};
+
+struct Rwstat {
+};
+
+/*
+  * fcall is the primary packet structure
+  *
+  */
+
+struct v9fs_fcall {
+	u32 size;
+	u8 id;
+	u16 tag;
+
+	union {
+		struct Tversion tversion;
+		struct Rversion rversion;
+		struct Tauth tauth;
+		struct Rauth rauth;
+		struct Rerror rerror;
+		struct Tflush tflush;
+		struct Rflush rflush;
+		struct Tattach tattach;
+		struct Rattach rattach;
+		struct Twalk twalk;
+		struct Rwalk rwalk;
+		struct Topen topen;
+		struct Ropen ropen;
+		struct Tcreate tcreate;
+		struct Rcreate rcreate;
+		struct Tread tread;
+		struct Rread rread;
+		struct Twrite twrite;
+		struct Rwrite rwrite;
+		struct Tclunk tclunk;
+		struct Rclunk rclunk;
+		struct Tremove tremove;
+		struct Rremove rremove;
+		struct Tstat tstat;
+		struct Rstat rstat;
+		struct Twstat twstat;
+		struct Rwstat rwstat;
+	} params;
+};
+
+#define FCALL_ERROR(fcall) (fcall ? fcall->params.rerror.error : "")
+
+int v9fs_t_version(struct v9fs_session_info *v9ses, u32 msize,
+		   char *version, struct v9fs_fcall **rcall);
+
+int v9fs_t_attach(struct v9fs_session_info *v9ses, char *uname, char *aname,
+		  u32 fid, u32 afid, struct v9fs_fcall **rcall);
+
+int v9fs_t_clunk(struct v9fs_session_info *v9ses, u32 fid,
+		 struct v9fs_fcall **rcall);
+
+int v9fs_t_flush(struct v9fs_session_info *v9ses, u16 oldtag);
+
+int v9fs_t_stat(struct v9fs_session_info *v9ses, u32 fid,
+		struct v9fs_fcall **rcall);
+
+int v9fs_t_wstat(struct v9fs_session_info *v9ses, u32 fid,
+		 struct v9fs_stat *stat, struct v9fs_fcall **rcall);
+
+int v9fs_t_walk(struct v9fs_session_info *v9ses, u32 fid, u32 newfid,
+		char *name, struct v9fs_fcall **rcall);
+
+int v9fs_t_open(struct v9fs_session_info *v9ses, u32 fid, u8 mode,
+		struct v9fs_fcall **rcall);
+
+int v9fs_t_remove(struct v9fs_session_info *v9ses, u32 fid,
+		  struct v9fs_fcall **rcall);
+
+int v9fs_t_create(struct v9fs_session_info *v9ses, u32 fid, char *name,
+		  u32 perm, u8 mode, struct v9fs_fcall **rcall);
+
+int v9fs_t_read(struct v9fs_session_info *v9ses, u32 fid,
+		u64 offset, u32 count, struct v9fs_fcall **rcall);
+
+int v9fs_t_write(struct v9fs_session_info *v9ses, u32 fid, u64 offset,
+		 u32 count, void *data, struct v9fs_fcall **rcall);
diff --git a/fs/9p/Makefile b/fs/9p/Makefile
new file mode 100644
index 00000000000..e4e4ffe5a7d
--- /dev/null
+++ b/fs/9p/Makefile
@@ -0,0 +1,17 @@
+obj-$(CONFIG_9P_FS) := 9p2000.o
+
+9p2000-objs := \
+	vfs_super.o \
+	vfs_inode.o \
+	vfs_file.o \
+	vfs_dir.o \
+	vfs_dentry.o \
+	error.o \
+	mux.o \
+	trans_fd.o \
+	trans_sock.o \
+	9p.o \
+	conv.o \
+	v9fs.o \
+	fid.o
+
diff --git a/fs/9p/conv.c b/fs/9p/conv.c
new file mode 100644
index 00000000000..1554731bd65
--- /dev/null
+++ b/fs/9p/conv.c
@@ -0,0 +1,693 @@
+/*
+ * linux/fs/9p/conv.c
+ *
+ * 9P protocol conversion functions
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "conv.h"
+
+/*
+ * Buffer to help with string parsing
+ */
+struct cbuf {
+	unsigned char *sp;
+	unsigned char *p;
+	unsigned char *ep;
+};
+
+static inline void buf_init(struct cbuf *buf, void *data, int datalen)
+{
+	buf->sp = buf->p = data;
+	buf->ep = data + datalen;
+}
+
+static inline int buf_check_overflow(struct cbuf *buf)
+{
+	return buf->p > buf->ep;
+}
+
+static inline void buf_check_size(struct cbuf *buf, int len)
+{
+	if (buf->p+len > buf->ep) {
+		if (buf->p < buf->ep) {
+			eprintk(KERN_ERR, "buffer overflow\n");
+			buf->p = buf->ep + 1;
+		}
+	}
+}
+
+static inline void *buf_alloc(struct cbuf *buf, int len)
+{
+	void *ret = NULL;
+
+	buf_check_size(buf, len);
+	ret = buf->p;
+	buf->p += len;
+
+	return ret;
+}
+
+static inline void buf_put_int8(struct cbuf *buf, u8 val)
+{
+	buf_check_size(buf, 1);
+
+	buf->p[0] = val;
+	buf->p++;
+}
+
+static inline void buf_put_int16(struct cbuf *buf, u16 val)
+{
+	buf_check_size(buf, 2);
+
+	*(__le16 *) buf->p = cpu_to_le16(val);
+	buf->p += 2;
+}
+
+static inline void buf_put_int32(struct cbuf *buf, u32 val)
+{
+	buf_check_size(buf, 4);
+
+	*(__le32 *)buf->p = cpu_to_le32(val);
+	buf->p += 4;
+}
+
+static inline void buf_put_int64(struct cbuf *buf, u64 val)
+{
+	buf_check_size(buf, 8);
+
+	*(__le64 *)buf->p = cpu_to_le64(val);
+	buf->p += 8;
+}
+
+static inline void buf_put_stringn(struct cbuf *buf, const char *s, u16 slen)
+{
+	buf_check_size(buf, slen + 2);
+
+	buf_put_int16(buf, slen);
+	memcpy(buf->p, s, slen);
+	buf->p += slen;
+}
+
+static inline void buf_put_string(struct cbuf *buf, const char *s)
+{
+	buf_put_stringn(buf, s, strlen(s));
+}
+
+static inline void buf_put_data(struct cbuf *buf, void *data, u32 datalen)
+{
+	buf_check_size(buf, datalen);
+
+	memcpy(buf->p, data, datalen);
+	buf->p += datalen;
+}
+
+static inline u8 buf_get_int8(struct cbuf *buf)
+{
+	u8 ret = 0;
+
+	buf_check_size(buf, 1);
+	ret = buf->p[0];
+
+	buf->p++;
+
+	return ret;
+}
+
+static inline u16 buf_get_int16(struct cbuf *buf)
+{
+	u16 ret = 0;
+
+	buf_check_size(buf, 2);
+	ret = le16_to_cpu(*(__le16 *)buf->p);
+
+	buf->p += 2;
+
+	return ret;
+}
+
+static inline u32 buf_get_int32(struct cbuf *buf)
+{
+	u32 ret = 0;
+
+	buf_check_size(buf, 4);
+	ret = le32_to_cpu(*(__le32 *)buf->p);
+
+	buf->p += 4;
+
+	return ret;
+}
+
+static inline u64 buf_get_int64(struct cbuf *buf)
+{
+	u64 ret = 0;
+
+	buf_check_size(buf, 8);
+	ret = le64_to_cpu(*(__le64 *)buf->p);
+
+	buf->p += 8;
+
+	return ret;
+}
+
+static inline int
+buf_get_string(struct cbuf *buf, char *data, unsigned int datalen)
+{
+
+	u16 len = buf_get_int16(buf);
+	buf_check_size(buf, len);
+	if (len + 1 > datalen)
+		return 0;
+
+	memcpy(data, buf->p, len);
+	data[len] = 0;
+	buf->p += len;
+
+	return len + 1;
+}
+
+static inline char *buf_get_stringb(struct cbuf *buf, struct cbuf *sbuf)
+{
+	char *ret = NULL;
+	int n = buf_get_string(buf, sbuf->p, sbuf->ep - sbuf->p);
+
+	if (n > 0) {
+		ret = sbuf->p;
+		sbuf->p += n;
+	}
+
+	return ret;
+}
+
+static inline int buf_get_data(struct cbuf *buf, void *data, int datalen)
+{
+	buf_check_size(buf, datalen);
+
+	memcpy(data, buf->p, datalen);
+	buf->p += datalen;
+
+	return datalen;
+}
+
+static inline void *buf_get_datab(struct cbuf *buf, struct cbuf *dbuf,
+				  int datalen)
+{
+	char *ret = NULL;
+	int n = 0;
+
+	buf_check_size(dbuf, datalen);
+
+	n = buf_get_data(buf, dbuf->p, datalen);
+
+	if (n > 0) {
+		ret = dbuf->p;
+		dbuf->p += n;
+	}
+
+	return ret;
+}
+
+/**
+ * v9fs_size_stat - calculate the size of a variable length stat struct
+ * @v9ses: session information
+ * @stat: metadata (stat) structure
+ *
+ */
+
+static int v9fs_size_stat(struct v9fs_session_info *v9ses,
+			  struct v9fs_stat *stat)
+{
+	int size = 0;
+
+	if (stat == NULL) {
+		eprintk(KERN_ERR, "v9fs_size_stat: got a NULL stat pointer\n");
+		return 0;
+	}
+
+	size =			/* 2 + *//* size[2] */
+	    2 +			/* type[2] */
+	    4 +			/* dev[4] */
+	    1 +			/* qid.type[1] */
+	    4 +			/* qid.vers[4] */
+	    8 +			/* qid.path[8] */
+	    4 +			/* mode[4] */
+	    4 +			/* atime[4] */
+	    4 +			/* mtime[4] */
+	    8 +			/* length[8] */
+	    8;			/* minimum sum of string lengths */
+
+	if (stat->name)
+		size += strlen(stat->name);
+	if (stat->uid)
+		size += strlen(stat->uid);
+	if (stat->gid)
+		size += strlen(stat->gid);
+	if (stat->muid)
+		size += strlen(stat->muid);
+
+	if (v9ses->extended) {
+		size += 4 +	/* n_uid[4] */
+		    4 +		/* n_gid[4] */
+		    4 +		/* n_muid[4] */
+		    2;		/* string length of extension[4] */
+		if (stat->extension)
+			size += strlen(stat->extension);
+	}
+
+	return size;
+}
+
+/**
+ * serialize_stat - safely format a stat structure for transmission
+ * @v9ses: session info
+ * @stat: metadata (stat) structure
+ * @bufp: buffer to serialize structure into
+ *
+ */
+
+static int
+serialize_stat(struct v9fs_session_info *v9ses, struct v9fs_stat *stat,
+	       struct cbuf *bufp)
+{
+	buf_put_int16(bufp, stat->size);
+	buf_put_int16(bufp, stat->type);
+	buf_put_int32(bufp, stat->dev);
+	buf_put_int8(bufp, stat->qid.type);
+	buf_put_int32(bufp, stat->qid.version);
+	buf_put_int64(bufp, stat->qid.path);
+	buf_put_int32(bufp, stat->mode);
+	buf_put_int32(bufp, stat->atime);
+	buf_put_int32(bufp, stat->mtime);
+	buf_put_int64(bufp, stat->length);
+
+	buf_put_string(bufp, stat->name);
+	buf_put_string(bufp, stat->uid);
+	buf_put_string(bufp, stat->gid);
+	buf_put_string(bufp, stat->muid);
+
+	if (v9ses->extended) {
+		buf_put_string(bufp, stat->extension);
+		buf_put_int32(bufp, stat->n_uid);
+		buf_put_int32(bufp, stat->n_gid);
+		buf_put_int32(bufp, stat->n_muid);
+	}
+
+	if (buf_check_overflow(bufp))
+		return 0;
+
+	return stat->size;
+}
+
+/**
+ * deserialize_stat - safely decode a recieved metadata (stat) structure
+ * @v9ses: session info
+ * @bufp: buffer to deserialize
+ * @stat: metadata (stat) structure
+ * @dbufp: buffer to deserialize variable strings into
+ *
+ */
+
+static inline int
+deserialize_stat(struct v9fs_session_info *v9ses, struct cbuf *bufp,
+		 struct v9fs_stat *stat, struct cbuf *dbufp)
+{
+
+	stat->size = buf_get_int16(bufp);
+	stat->type = buf_get_int16(bufp);
+	stat->dev = buf_get_int32(bufp);
+	stat->qid.type = buf_get_int8(bufp);
+	stat->qid.version = buf_get_int32(bufp);
+	stat->qid.path = buf_get_int64(bufp);
+	stat->mode = buf_get_int32(bufp);
+	stat->atime = buf_get_int32(bufp);
+	stat->mtime = buf_get_int32(bufp);
+	stat->length = buf_get_int64(bufp);
+	stat->name = buf_get_stringb(bufp, dbufp);
+	stat->uid = buf_get_stringb(bufp, dbufp);
+	stat->gid = buf_get_stringb(bufp, dbufp);
+	stat->muid = buf_get_stringb(bufp, dbufp);
+
+	if (v9ses->extended) {
+		stat->extension = buf_get_stringb(bufp, dbufp);
+		stat->n_uid = buf_get_int32(bufp);
+		stat->n_gid = buf_get_int32(bufp);
+		stat->n_muid = buf_get_int32(bufp);
+	}
+
+	if (buf_check_overflow(bufp) || buf_check_overflow(dbufp))
+		return 0;
+
+	return stat->size + 2;
+}
+
+/**
+ * deserialize_statb - wrapper for decoding a received metadata structure
+ * @v9ses: session info
+ * @bufp: buffer to deserialize
+ * @dbufp: buffer to deserialize variable strings into
+ *
+ */
+
+static inline struct v9fs_stat *deserialize_statb(struct v9fs_session_info
+						  *v9ses, struct cbuf *bufp,
+						  struct cbuf *dbufp)
+{
+	struct v9fs_stat *ret = buf_alloc(dbufp, sizeof(struct v9fs_stat));
+
+	if (ret) {
+		int n = deserialize_stat(v9ses, bufp, ret, dbufp);
+		if (n <= 0)
+			return NULL;
+	}
+
+	return ret;
+}
+
+/**
+ * v9fs_deserialize_stat - decode a received metadata structure
+ * @v9ses: session info
+ * @buf: buffer to deserialize
+ * @buflen: length of received buffer
+ * @stat: metadata structure to decode into
+ * @statlen: length of destination metadata structure
+ *
+ */
+
+int
+v9fs_deserialize_stat(struct v9fs_session_info *v9ses, void *buf,
+		      u32 buflen, struct v9fs_stat *stat, u32 statlen)
+{
+	struct cbuf buffer;
+	struct cbuf *bufp = &buffer;
+	struct cbuf dbuffer;
+	struct cbuf *dbufp = &dbuffer;
+
+	buf_init(bufp, buf, buflen);
+	buf_init(dbufp, (char *)stat + sizeof(struct v9fs_stat),
+		 statlen - sizeof(struct v9fs_stat));
+
+	return deserialize_stat(v9ses, bufp, stat, dbufp);
+}
+
+static inline int
+v9fs_size_fcall(struct v9fs_session_info *v9ses, struct v9fs_fcall *fcall)
+{
+	int size = 4 + 1 + 2;	/* size[4] msg[1] tag[2] */
+	int i = 0;
+
+	switch (fcall->id) {
+	default:
+		eprintk(KERN_ERR, "bad msg type %d\n", fcall->id);
+		return 0;
+	case TVERSION:		/* msize[4] version[s] */
+		size += 4 + 2 + strlen(fcall->params.tversion.version);
+		break;
+	case TAUTH:		/* afid[4] uname[s] aname[s] */
+		size += 4 + 2 + strlen(fcall->params.tauth.uname) +
+		    2 + strlen(fcall->params.tauth.aname);
+		break;
+	case TFLUSH:		/* oldtag[2] */
+		size += 2;
+		break;
+	case TATTACH:		/* fid[4] afid[4] uname[s] aname[s] */
+		size += 4 + 4 + 2 + strlen(fcall->params.tattach.uname) +
+		    2 + strlen(fcall->params.tattach.aname);
+		break;
+	case TWALK:		/* fid[4] newfid[4] nwname[2] nwname*(wname[s]) */
+		size += 4 + 4 + 2;
+		/* now compute total for the array of names */
+		for (i = 0; i < fcall->params.twalk.nwname; i++)
+			size += 2 + strlen(fcall->params.twalk.wnames[i]);
+		break;
+	case TOPEN:		/* fid[4] mode[1] */
+		size += 4 + 1;
+		break;
+	case TCREATE:		/* fid[4] name[s] perm[4] mode[1] */
+		size += 4 + 2 + strlen(fcall->params.tcreate.name) + 4 + 1;
+		break;
+	case TREAD:		/* fid[4] offset[8] count[4] */
+		size += 4 + 8 + 4;
+		break;
+	case TWRITE:		/* fid[4] offset[8] count[4] data[count] */
+		size += 4 + 8 + 4 + fcall->params.twrite.count;
+		break;
+	case TCLUNK:		/* fid[4] */
+		size += 4;
+		break;
+	case TREMOVE:		/* fid[4] */
+		size += 4;
+		break;
+	case TSTAT:		/* fid[4] */
+		size += 4;
+		break;
+	case TWSTAT:		/* fid[4] stat[n] */
+		fcall->params.twstat.stat->size =
+		    v9fs_size_stat(v9ses, fcall->params.twstat.stat);
+		size += 4 + 2 + 2 + fcall->params.twstat.stat->size;
+	}
+	return size;
+}
+
+/*
+ * v9fs_serialize_fcall - marshall fcall struct into a packet
+ * @v9ses: session information
+ * @fcall: structure to convert
+ * @data: buffer to serialize fcall into
+ * @datalen: length of buffer to serialize fcall into
+ *
+ */
+
+int
+v9fs_serialize_fcall(struct v9fs_session_info *v9ses, struct v9fs_fcall *fcall,
+		     void *data, u32 datalen)
+{
+	int i = 0;
+	struct v9fs_stat *stat = NULL;
+	struct cbuf buffer;
+	struct cbuf *bufp = &buffer;
+
+	buf_init(bufp, data, datalen);
+
+	if (!fcall) {
+		eprintk(KERN_ERR, "no fcall\n");
+		return -EINVAL;
+	}
+
+	fcall->size = v9fs_size_fcall(v9ses, fcall);
+
+	buf_put_int32(bufp, fcall->size);
+	buf_put_int8(bufp, fcall->id);
+	buf_put_int16(bufp, fcall->tag);
+
+	dprintk(DEBUG_CONV, "size %d id %d tag %d\n", fcall->size, fcall->id,
+		fcall->tag);
+
+	/* now encode it */
+	switch (fcall->id) {
+	default:
+		eprintk(KERN_ERR, "bad msg type: %d\n", fcall->id);
+		return -EPROTO;
+	case TVERSION:
+		buf_put_int32(bufp, fcall->params.tversion.msize);
+		buf_put_string(bufp, fcall->params.tversion.version);
+		break;
+	case TAUTH:
+		buf_put_int32(bufp, fcall->params.tauth.afid);
+		buf_put_string(bufp, fcall->params.tauth.uname);
+		buf_put_string(bufp, fcall->params.tauth.aname);
+		break;
+	case TFLUSH:
+		buf_put_int16(bufp, fcall->params.tflush.oldtag);
+		break;
+	case TATTACH:
+		buf_put_int32(bufp, fcall->params.tattach.fid);
+		buf_put_int32(bufp, fcall->params.tattach.afid);
+		buf_put_string(bufp, fcall->params.tattach.uname);
+		buf_put_string(bufp, fcall->params.tattach.aname);
+		break;
+	case TWALK:
+		buf_put_int32(bufp, fcall->params.twalk.fid);
+		buf_put_int32(bufp, fcall->params.twalk.newfid);
+		buf_put_int16(bufp, fcall->params.twalk.nwname);
+		for (i = 0; i < fcall->params.twalk.nwname; i++)
+			buf_put_string(bufp, fcall->params.twalk.wnames[i]);
+		break;
+	case TOPEN:
+		buf_put_int32(bufp, fcall->params.topen.fid);
+		buf_put_int8(bufp, fcall->params.topen.mode);
+		break;
+	case TCREATE:
+		buf_put_int32(bufp, fcall->params.tcreate.fid);
+		buf_put_string(bufp, fcall->params.tcreate.name);
+		buf_put_int32(bufp, fcall->params.tcreate.perm);
+		buf_put_int8(bufp, fcall->params.tcreate.mode);
+		break;
+	case TREAD:
+		buf_put_int32(bufp, fcall->params.tread.fid);
+		buf_put_int64(bufp, fcall->params.tread.offset);
+		buf_put_int32(bufp, fcall->params.tread.count);
+		break;
+	case TWRITE:
+		buf_put_int32(bufp, fcall->params.twrite.fid);
+		buf_put_int64(bufp, fcall->params.twrite.offset);
+		buf_put_int32(bufp, fcall->params.twrite.count);
+		buf_put_data(bufp, fcall->params.twrite.data,
+			     fcall->params.twrite.count);
+		break;
+	case TCLUNK:
+		buf_put_int32(bufp, fcall->params.tclunk.fid);
+		break;
+	case TREMOVE:
+		buf_put_int32(bufp, fcall->params.tremove.fid);
+		break;
+	case TSTAT:
+		buf_put_int32(bufp, fcall->params.tstat.fid);
+		break;
+	case TWSTAT:
+		buf_put_int32(bufp, fcall->params.twstat.fid);
+		stat = fcall->params.twstat.stat;
+
+		buf_put_int16(bufp, stat->size + 2);
+		serialize_stat(v9ses, stat, bufp);
+		break;
+	}
+
+	if (buf_check_overflow(bufp))
+		return -EIO;
+
+	return fcall->size;
+}
+
+/**
+ * deserialize_fcall - unmarshal a response
+ * @v9ses: session information
+ * @msgsize: size of rcall message
+ * @buf: recieved buffer
+ * @buflen: length of received buffer
+ * @rcall: fcall structure to populate
+ * @rcalllen: length of fcall structure to populate
+ *
+ */
+
+int
+v9fs_deserialize_fcall(struct v9fs_session_info *v9ses, u32 msgsize,
+		       void *buf, u32 buflen, struct v9fs_fcall *rcall,
+		       int rcalllen)
+{
+
+	struct cbuf buffer;
+	struct cbuf *bufp = &buffer;
+	struct cbuf dbuffer;
+	struct cbuf *dbufp = &dbuffer;
+	int i = 0;
+
+	buf_init(bufp, buf, buflen);
+	buf_init(dbufp, (char *)rcall + sizeof(struct v9fs_fcall),
+		 rcalllen - sizeof(struct v9fs_fcall));
+
+	rcall->size = msgsize;
+	rcall->id = buf_get_int8(bufp);
+	rcall->tag = buf_get_int16(bufp);
+
+	dprintk(DEBUG_CONV, "size %d id %d tag %d\n", rcall->size, rcall->id,
+		rcall->tag);
+	switch (rcall->id) {
+	default:
+		eprintk(KERN_ERR, "unknown message type: %d\n", rcall->id);
+		return -EPROTO;
+	case RVERSION:
+		rcall->params.rversion.msize = buf_get_int32(bufp);
+		rcall->params.rversion.version = buf_get_stringb(bufp, dbufp);
+		break;
+	case RFLUSH:
+		break;
+	case RATTACH:
+		rcall->params.rattach.qid.type = buf_get_int8(bufp);
+		rcall->params.rattach.qid.version = buf_get_int32(bufp);
+		rcall->params.rattach.qid.path = buf_get_int64(bufp);
+		break;
+	case RWALK:
+		rcall->params.rwalk.nwqid = buf_get_int16(bufp);
+		rcall->params.rwalk.wqids = buf_alloc(bufp,
+		      rcall->params.rwalk.nwqid * sizeof(struct v9fs_qid));
+		if (rcall->params.rwalk.wqids)
+			for (i = 0; i < rcall->params.rwalk.nwqid; i++) {
+				rcall->params.rwalk.wqids[i].type =
+				    buf_get_int8(bufp);
+				rcall->params.rwalk.wqids[i].version =
+				    buf_get_int16(bufp);
+				rcall->params.rwalk.wqids[i].path =
+				    buf_get_int64(bufp);
+			}
+		break;
+	case ROPEN:
+		rcall->params.ropen.qid.type = buf_get_int8(bufp);
+		rcall->params.ropen.qid.version = buf_get_int32(bufp);
+		rcall->params.ropen.qid.path = buf_get_int64(bufp);
+		rcall->params.ropen.iounit = buf_get_int32(bufp);
+		break;
+	case RCREATE:
+		rcall->params.rcreate.qid.type = buf_get_int8(bufp);
+		rcall->params.rcreate.qid.version = buf_get_int32(bufp);
+		rcall->params.rcreate.qid.path = buf_get_int64(bufp);
+		rcall->params.rcreate.iounit = buf_get_int32(bufp);
+		break;
+	case RREAD:
+		rcall->params.rread.count = buf_get_int32(bufp);
+		rcall->params.rread.data = buf_get_datab(bufp, dbufp,
+			rcall->params.rread.count);
+		break;
+	case RWRITE:
+		rcall->params.rwrite.count = buf_get_int32(bufp);
+		break;
+	case RCLUNK:
+		break;
+	case RREMOVE:
+		break;
+	case RSTAT:
+		buf_get_int16(bufp);
+		rcall->params.rstat.stat =
+		    deserialize_statb(v9ses, bufp, dbufp);
+		break;
+	case RWSTAT:
+		break;
+	case RERROR:
+		rcall->params.rerror.error = buf_get_stringb(bufp, dbufp);
+		if (v9ses->extended)
+			rcall->params.rerror.errno = buf_get_int16(bufp);
+		break;
+	}
+
+	if (buf_check_overflow(bufp) || buf_check_overflow(dbufp))
+		return -EIO;
+
+	return rcall->size;
+}
diff --git a/fs/9p/conv.h b/fs/9p/conv.h
new file mode 100644
index 00000000000..ee849613c61
--- /dev/null
+++ b/fs/9p/conv.h
@@ -0,0 +1,36 @@
+/*
+ * linux/fs/9p/conv.h
+ *
+ * 9P protocol conversion definitions
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+int v9fs_deserialize_stat(struct v9fs_session_info *, void *buf,
+			  u32 buflen, struct v9fs_stat *stat, u32 statlen);
+int v9fs_serialize_fcall(struct v9fs_session_info *, struct v9fs_fcall *tcall,
+			 void *buf, u32 buflen);
+int v9fs_deserialize_fcall(struct v9fs_session_info *, u32 msglen,
+			   void *buf, u32 buflen, struct v9fs_fcall *rcall,
+			   int rcalllen);
+
+/* this one is actually in error.c right now */
+int v9fs_errstr2errno(char *errstr);
diff --git a/fs/9p/debug.h b/fs/9p/debug.h
new file mode 100644
index 00000000000..4445f06919d
--- /dev/null
+++ b/fs/9p/debug.h
@@ -0,0 +1,70 @@
+/*
+ *  linux/fs/9p/debug.h - V9FS Debug Definitions
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define DEBUG_ERROR		(1<<0)
+#define DEBUG_CURRENT		(1<<1)
+#define DEBUG_9P	        (1<<2)
+#define DEBUG_VFS	        (1<<3)
+#define DEBUG_CONV		(1<<4)
+#define DEBUG_MUX		(1<<5)
+#define DEBUG_TRANS		(1<<6)
+#define DEBUG_SLABS	      	(1<<7)
+
+#define DEBUG_DUMP_PKT		0
+
+extern int v9fs_debug_level;
+
+#define dprintk(level, format, arg...) \
+do {  \
+	if((v9fs_debug_level & level)==level) \
+		printk(KERN_NOTICE "-- %s (%d): " \
+		format , __FUNCTION__, current->pid , ## arg); \
+} while(0)
+
+#define eprintk(level, format, arg...) \
+do { \
+	printk(level "v9fs: %s (%d): " \
+		format , __FUNCTION__, current->pid , ## arg); \
+} while(0)
+
+#if DEBUG_DUMP_PKT
+static inline void dump_data(const unsigned char *data, unsigned int datalen)
+{
+	int i, j;
+	int len = datalen;
+
+	printk(KERN_DEBUG "data ");
+	for (i = 0; i < len; i += 4) {
+		for (j = 0; (j < 4) && (i + j < len); j++)
+			printk(KERN_DEBUG "%02x", data[i + j]);
+		printk(KERN_DEBUG " ");
+	}
+	printk(KERN_DEBUG "\n");
+}
+#else				/* DEBUG_DUMP_PKT */
+static inline void dump_data(const unsigned char *data, unsigned int datalen)
+{
+
+}
+#endif				/* DEBUG_DUMP_PKT */
diff --git a/fs/9p/error.c b/fs/9p/error.c
new file mode 100644
index 00000000000..fee5d19179c
--- /dev/null
+++ b/fs/9p/error.c
@@ -0,0 +1,93 @@
+/*
+ * linux/fs/9p/error.c
+ *
+ * Error string handling
+ *
+ * Plan 9 uses error strings, Unix uses error numbers.  These functions
+ * try to help manage that and provide for dynamically adding error
+ * mappings.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/list.h>
+#include <linux/jhash.h>
+
+#include "debug.h"
+#include "error.h"
+
+/**
+ * v9fs_error_init - preload
+ * @errstr: error string
+ *
+ */
+
+int v9fs_error_init(void)
+{
+	struct errormap *c;
+	int bucket;
+
+	/* initialize hash table */
+	for (bucket = 0; bucket < ERRHASHSZ; bucket++)
+		INIT_HLIST_HEAD(&hash_errmap[bucket]);
+
+	/* load initial error map into hash table */
+	for (c = errmap; c->name != NULL; c++) {
+		bucket = jhash(c->name, strlen(c->name), 0) % ERRHASHSZ;
+		INIT_HLIST_NODE(&c->list);
+		hlist_add_head(&c->list, &hash_errmap[bucket]);
+	}
+
+	return 1;
+}
+
+/**
+ * errstr2errno - convert error string to error number
+ * @errstr: error string
+ *
+ */
+
+int v9fs_errstr2errno(char *errstr)
+{
+	int errno = 0;
+	struct hlist_node *p = NULL;
+	struct errormap *c = NULL;
+	int bucket = jhash(errstr, strlen(errstr), 0) % ERRHASHSZ;
+
+	hlist_for_each_entry(c, p, &hash_errmap[bucket], list) {
+		if (!strcmp(c->name, errstr)) {
+			errno = c->val;
+			break;
+		}
+	}
+
+	if (errno == 0) {
+		/* TODO: if error isn't found, add it dynamically */
+		printk(KERN_ERR "%s: errstr :%s: not found\n", __FUNCTION__,
+		       errstr);
+		errno = 1;
+	}
+
+	return -errno;
+}
diff --git a/fs/9p/error.h b/fs/9p/error.h
new file mode 100644
index 00000000000..78f89acf7c9
--- /dev/null
+++ b/fs/9p/error.h
@@ -0,0 +1,178 @@
+/*
+ * linux/fs/9p/error.h
+ *
+ * Huge Nasty Error Table
+ *
+ * Plan 9 uses error strings, Unix uses error numbers.  This table tries to
+ * match UNIX strings and Plan 9 strings to unix error numbers.  It is used
+ * to preload the dynamic error table which can also track user-specific error
+ * strings.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/errno.h>
+#include <asm/errno.h>
+
+struct errormap {
+	char *name;
+	int val;
+
+	struct hlist_node list;
+};
+
+#define ERRHASHSZ		32
+static struct hlist_head hash_errmap[ERRHASHSZ];
+
+/* FixMe - reduce to a reasonable size */
+static struct errormap errmap[] = {
+	{"Operation not permitted", EPERM},
+	{"wstat prohibited", EPERM},
+	{"No such file or directory", ENOENT},
+	{"directory entry not found", ENOENT},
+	{"file not found", ENOENT},
+	{"Interrupted system call", EINTR},
+	{"Input/output error", EIO},
+	{"No such device or address", ENXIO},
+	{"Argument list too long", E2BIG},
+	{"Bad file descriptor", EBADF},
+	{"Resource temporarily unavailable", EAGAIN},
+	{"Cannot allocate memory", ENOMEM},
+	{"Permission denied", EACCES},
+	{"Bad address", EFAULT},
+	{"Block device required", ENOTBLK},
+	{"Device or resource busy", EBUSY},
+	{"File exists", EEXIST},
+	{"Invalid cross-device link", EXDEV},
+	{"No such device", ENODEV},
+	{"Not a directory", ENOTDIR},
+	{"Is a directory", EISDIR},
+	{"Invalid argument", EINVAL},
+	{"Too many open files in system", ENFILE},
+	{"Too many open files", EMFILE},
+	{"Text file busy", ETXTBSY},
+	{"File too large", EFBIG},
+	{"No space left on device", ENOSPC},
+	{"Illegal seek", ESPIPE},
+	{"Read-only file system", EROFS},
+	{"Too many links", EMLINK},
+	{"Broken pipe", EPIPE},
+	{"Numerical argument out of domain", EDOM},
+	{"Numerical result out of range", ERANGE},
+	{"Resource deadlock avoided", EDEADLK},
+	{"File name too long", ENAMETOOLONG},
+	{"No locks available", ENOLCK},
+	{"Function not implemented", ENOSYS},
+	{"Directory not empty", ENOTEMPTY},
+	{"Too many levels of symbolic links", ELOOP},
+	{"No message of desired type", ENOMSG},
+	{"Identifier removed", EIDRM},
+	{"No data available", ENODATA},
+	{"Machine is not on the network", ENONET},
+	{"Package not installed", ENOPKG},
+	{"Object is remote", EREMOTE},
+	{"Link has been severed", ENOLINK},
+	{"Communication error on send", ECOMM},
+	{"Protocol error", EPROTO},
+	{"Bad message", EBADMSG},
+	{"File descriptor in bad state", EBADFD},
+	{"Streams pipe error", ESTRPIPE},
+	{"Too many users", EUSERS},
+	{"Socket operation on non-socket", ENOTSOCK},
+	{"Message too long", EMSGSIZE},
+	{"Protocol not available", ENOPROTOOPT},
+	{"Protocol not supported", EPROTONOSUPPORT},
+	{"Socket type not supported", ESOCKTNOSUPPORT},
+	{"Operation not supported", EOPNOTSUPP},
+	{"Protocol family not supported", EPFNOSUPPORT},
+	{"Network is down", ENETDOWN},
+	{"Network is unreachable", ENETUNREACH},
+	{"Network dropped connection on reset", ENETRESET},
+	{"Software caused connection abort", ECONNABORTED},
+	{"Connection reset by peer", ECONNRESET},
+	{"No buffer space available", ENOBUFS},
+	{"Transport endpoint is already connected", EISCONN},
+	{"Transport endpoint is not connected", ENOTCONN},
+	{"Cannot send after transport endpoint shutdown", ESHUTDOWN},
+	{"Connection timed out", ETIMEDOUT},
+	{"Connection refused", ECONNREFUSED},
+	{"Host is down", EHOSTDOWN},
+	{"No route to host", EHOSTUNREACH},
+	{"Operation already in progress", EALREADY},
+	{"Operation now in progress", EINPROGRESS},
+	{"Is a named type file", EISNAM},
+	{"Remote I/O error", EREMOTEIO},
+	{"Disk quota exceeded", EDQUOT},
+/* errors from fossil, vacfs, and u9fs */
+	{"fid unknown or out of range", EBADF},
+	{"permission denied", EACCES},
+	{"file does not exist", ENOENT},
+	{"authentication failed", ECONNREFUSED},
+	{"bad offset in directory read", ESPIPE},
+	{"bad use of fid", EBADF},
+	{"wstat can't convert between files and directories", EPERM},
+	{"directory is not empty", ENOTEMPTY},
+	{"file exists", EEXIST},
+	{"file already exists", EEXIST},
+	{"file or directory already exists", EEXIST},
+	{"fid already in use", EBADF},
+	{"file in use", ETXTBSY},
+	{"i/o error", EIO},
+	{"file already open for I/O", ETXTBSY},
+	{"illegal mode", EINVAL},
+	{"illegal name", ENAMETOOLONG},
+	{"not a directory", ENOTDIR},
+	{"not a member of proposed group", EPERM},
+	{"not owner", EACCES},
+	{"only owner can change group in wstat", EACCES},
+	{"read only file system", EROFS},
+	{"no access to special file", EPERM},
+	{"i/o count too large", EIO},
+	{"unknown group", EINVAL},
+	{"unknown user", EINVAL},
+	{"bogus wstat buffer", EPROTO},
+	{"exclusive use file already open", EAGAIN},
+	{"corrupted directory entry", EIO},
+	{"corrupted file entry", EIO},
+	{"corrupted block label", EIO},
+	{"corrupted meta data", EIO},
+	{"illegal offset", EINVAL},
+	{"illegal path element", ENOENT},
+	{"root of file system is corrupted", EIO},
+	{"corrupted super block", EIO},
+	{"protocol botch", EPROTO},
+	{"file system is full", ENOSPC},
+	{"file is in use", EAGAIN},
+	{"directory entry is not allocated", ENOENT},
+	{"file is read only", EROFS},
+	{"file has been removed", EIDRM},
+	{"only support truncation to zero length", EPERM},
+	{"cannot remove root", EPERM},
+	{"file too big", EFBIG},
+	{"venti i/o error", EIO},
+	/* these are not errors */
+	{"u9fs rhostsauth: no authentication required", 0},
+	{"u9fs authnone: no authentication required", 0},
+	{NULL, -1}
+};
+
+extern int v9fs_error_init(void);
+extern int v9fs_errstr2errno(char *errstr);
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
new file mode 100644
index 00000000000..821c9c4d76a
--- /dev/null
+++ b/fs/9p/fid.c
@@ -0,0 +1,241 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "transport.h"
+#include "mux.h"
+#include "conv.h"
+#include "fid.h"
+
+/**
+ * v9fs_fid_insert - add a fid to a dentry
+ * @fid: fid to add
+ * @dentry: dentry that it is being added to
+ *
+ */
+
+static int v9fs_fid_insert(struct v9fs_fid *fid, struct dentry *dentry)
+{
+	struct list_head *fid_list = (struct list_head *)dentry->d_fsdata;
+	dprintk(DEBUG_9P, "fid %d (%p) dentry %s (%p)\n", fid->fid, fid,
+		dentry->d_iname, dentry);
+	if (dentry->d_fsdata == NULL) {
+		dentry->d_fsdata =
+		    kmalloc(sizeof(struct list_head), GFP_KERNEL);
+		if (dentry->d_fsdata == NULL) {
+			dprintk(DEBUG_ERROR, "Out of memory\n");
+			return -ENOMEM;
+		}
+		fid_list = (struct list_head *)dentry->d_fsdata;
+		INIT_LIST_HEAD(fid_list);	/* Initialize list head */
+	}
+
+	fid->uid = current->uid;
+	fid->pid = current->pid;
+	list_add(&fid->list, fid_list);
+	return 0;
+}
+
+/**
+ * v9fs_fid_create - allocate a FID structure
+ * @dentry - dentry to link newly created fid to
+ *
+ */
+
+struct v9fs_fid *v9fs_fid_create(struct dentry *dentry)
+{
+	struct v9fs_fid *new;
+
+	new = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL);
+	if (new == NULL) {
+		dprintk(DEBUG_ERROR, "Out of Memory\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	new->fid = -1;
+	new->fidopen = 0;
+	new->fidcreate = 0;
+	new->fidclunked = 0;
+	new->iounit = 0;
+
+	if (v9fs_fid_insert(new, dentry) == 0)
+		return new;
+	else {
+		dprintk(DEBUG_ERROR, "Problems inserting to dentry\n");
+		kfree(new);
+		return NULL;
+	}
+}
+
+/**
+ * v9fs_fid_destroy - deallocate a FID structure
+ * @fid: fid to destroy
+ *
+ */
+
+void v9fs_fid_destroy(struct v9fs_fid *fid)
+{
+	list_del(&fid->list);
+	kfree(fid);
+}
+
+/**
+ * v9fs_fid_lookup - retrieve the right fid from a  particular dentry
+ * @dentry: dentry to look for fid in
+ * @type: intent of lookup (operation or traversal)
+ *
+ * search list of fids associated with a dentry for a fid with a matching
+ * thread id or uid.  If that fails, look up the dentry's parents to see if you
+ * can find a matching fid.
+ *
+ */
+
+struct v9fs_fid *v9fs_fid_lookup(struct dentry *dentry, int type)
+{
+	struct list_head *fid_list = (struct list_head *)dentry->d_fsdata;
+	struct v9fs_fid *current_fid = NULL;
+	struct v9fs_fid *temp = NULL;
+	struct v9fs_fid *return_fid = NULL;
+	int found_parent = 0;
+	int found_user = 0;
+
+	dprintk(DEBUG_9P, " dentry: %s (%p) type %d\n", dentry->d_iname, dentry,
+		type);
+
+	if (fid_list && !list_empty(fid_list)) {
+		list_for_each_entry_safe(current_fid, temp, fid_list, list) {
+			if (current_fid->uid == current->uid) {
+				if (return_fid == NULL) {
+					if ((type == FID_OP)
+					    || (!current_fid->fidopen)) {
+						return_fid = current_fid;
+						found_user = 1;
+					}
+				}
+			}
+			if (current_fid->pid == current->real_parent->pid) {
+				if ((return_fid == NULL) || (found_parent)
+				    || (found_user)) {
+					if ((type == FID_OP)
+					    || (!current_fid->fidopen)) {
+						return_fid = current_fid;
+						found_parent = 1;
+						found_user = 0;
+					}
+				}
+			}
+			if (current_fid->pid == current->pid) {
+				if ((type == FID_OP) ||
+				    (!current_fid->fidopen)) {
+					return_fid = current_fid;
+					found_parent = 0;
+					found_user = 0;
+				}
+			}
+		}
+	}
+
+	/* we are at the root but didn't match */
+	if ((!return_fid) && (dentry->d_parent == dentry)) {
+		/* TODO: clone attach with new uid */
+		return_fid = current_fid;
+	}
+
+	if (!return_fid) {
+		struct dentry *par = current->fs->pwd->d_parent;
+		int count = 1;
+		while (par != NULL) {
+			if (par == dentry)
+				break;
+			count++;
+			if (par == par->d_parent) {
+				dprintk(DEBUG_ERROR,
+					"got to root without finding dentry\n");
+				break;
+			}
+			par = par->d_parent;
+		}
+
+/* XXX - there may be some duplication we can get rid of */
+		if (par == dentry) {
+			/* we need to fid_lookup the starting point */
+			int fidnum = -1;
+			int oldfid = -1;
+			int result = -1;
+			struct v9fs_session_info *v9ses =
+			    v9fs_inode2v9ses(current->fs->pwd->d_inode);
+
+			current_fid =
+			    v9fs_fid_lookup(current->fs->pwd, FID_WALK);
+			if (current_fid == NULL) {
+				dprintk(DEBUG_ERROR,
+					"process cwd doesn't have a fid\n");
+				return return_fid;
+			}
+			oldfid = current_fid->fid;
+			par = current->fs->pwd;
+			/* TODO: take advantage of multiwalk */
+
+			fidnum = v9fs_get_idpool(&v9ses->fidpool);
+			if (fidnum < 0) {
+				dprintk(DEBUG_ERROR,
+					"could not get a new fid num\n");
+				return return_fid;
+			}
+
+			while (par != dentry) {
+				result =
+				    v9fs_t_walk(v9ses, oldfid, fidnum, "..",
+						NULL);
+				if (result < 0) {
+					dprintk(DEBUG_ERROR,
+						"problem walking to parent\n");
+
+					break;
+				}
+				oldfid = fidnum;
+				if (par == par->d_parent) {
+					dprintk(DEBUG_ERROR,
+						"can't find dentry\n");
+					break;
+				}
+				par = par->d_parent;
+			}
+			if (par == dentry) {
+				return_fid = v9fs_fid_create(dentry);
+				return_fid->fid = fidnum;
+			}
+		}
+	}
+
+	return return_fid;
+}
diff --git a/fs/9p/fid.h b/fs/9p/fid.h
new file mode 100644
index 00000000000..7db478ccca3
--- /dev/null
+++ b/fs/9p/fid.h
@@ -0,0 +1,57 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/list.h>
+
+#define FID_OP   0
+#define FID_WALK 1
+
+struct v9fs_fid {
+	struct list_head list;	 /* list of fids associated with a dentry */
+	struct list_head active; /* XXX - debug */
+
+	u32 fid;
+	unsigned char fidopen;	  /* set when fid is opened */
+	unsigned char fidcreate;  /* set when fid was just created */
+	unsigned char fidclunked; /* set when fid has already been clunked */
+
+	struct v9fs_qid qid;
+	u32 iounit;
+
+	/* readdir stuff */
+	int rdir_fpos;
+	loff_t rdir_pos;
+	struct v9fs_fcall *rdir_fcall;
+
+	/* management stuff */
+	pid_t pid;		/* thread associated with this fid */
+	uid_t uid;		/* user associated with this fid */
+
+	/* private data */
+	struct file *filp;	/* backpointer to File struct for open files */
+	struct v9fs_session_info *v9ses;	/* session info for this FID */
+};
+
+struct v9fs_fid *v9fs_fid_lookup(struct dentry *dentry, int type);
+void v9fs_fid_destroy(struct v9fs_fid *fid);
+struct v9fs_fid *v9fs_fid_create(struct dentry *);
diff --git a/fs/9p/mux.c b/fs/9p/mux.c
new file mode 100644
index 00000000000..8835b576f74
--- /dev/null
+++ b/fs/9p/mux.c
@@ -0,0 +1,475 @@
+/*
+ * linux/fs/9p/mux.c
+ *
+ * Protocol Multiplexer
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2004 by Latchesar Ionkov <lucho@ionkov.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/kthread.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "transport.h"
+#include "conv.h"
+#include "mux.h"
+
+/**
+ * dprintcond - print condition of session info
+ * @v9ses: session info structure
+ * @req: RPC request structure
+ *
+ */
+
+static inline int
+dprintcond(struct v9fs_session_info *v9ses, struct v9fs_rpcreq *req)
+{
+	dprintk(DEBUG_MUX, "condition: %d, %p\n", v9ses->transport->status,
+		req->rcall);
+	return 0;
+}
+
+/**
+ * xread - force read of a certain number of bytes
+ * @v9ses: session info structure
+ * @ptr: pointer to buffer
+ * @sz: number of bytes to read
+ *
+ * Chuck Cranor CS-533 project1
+ */
+
+static int xread(struct v9fs_session_info *v9ses, void *ptr, unsigned long sz)
+{
+	int rd = 0;
+	int ret = 0;
+	while (rd < sz) {
+		ret = v9ses->transport->read(v9ses->transport, ptr, sz - rd);
+		if (ret <= 0) {
+			dprintk(DEBUG_ERROR, "xread errno %d\n", ret);
+			return ret;
+		}
+		rd += ret;
+		ptr += ret;
+	}
+	return (rd);
+}
+
+/**
+ * read_message - read a full 9P2000 fcall packet
+ * @v9ses: session info structure
+ * @rcall: fcall structure to read into
+ * @rcalllen: size of fcall buffer
+ *
+ */
+
+static int
+read_message(struct v9fs_session_info *v9ses,
+	     struct v9fs_fcall *rcall, int rcalllen)
+{
+	unsigned char buf[4];
+	void *data;
+	int size = 0;
+	int res = 0;
+
+	res = xread(v9ses, buf, sizeof(buf));
+	if (res < 0) {
+		dprintk(DEBUG_ERROR,
+			"Reading of count field failed returned: %d\n", res);
+		return res;
+	}
+
+	if (res < 4) {
+		dprintk(DEBUG_ERROR,
+			"Reading of count field failed returned: %d\n", res);
+		return -EIO;
+	}
+
+	size = buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
+	dprintk(DEBUG_MUX, "got a packet count: %d\n", size);
+
+	/* adjust for the four bytes of size */
+	size -= 4;
+
+	if (size > v9ses->maxdata) {
+		dprintk(DEBUG_ERROR, "packet too big: %d\n", size);
+		return -E2BIG;
+	}
+
+	data = kmalloc(size, GFP_KERNEL);
+	if (!data) {
+		eprintk(KERN_WARNING, "out of memory\n");
+		return -ENOMEM;
+	}
+
+	res = xread(v9ses, data, size);
+	if (res < size) {
+		dprintk(DEBUG_ERROR, "Reading of fcall failed returned: %d\n",
+			res);
+		kfree(data);
+		return res;
+	}
+
+	/* we now have an in-memory string that is the reply.
+	 * deserialize it. There is very little to go wrong at this point
+	 * save for v9fs_alloc errors.
+	 */
+	res = v9fs_deserialize_fcall(v9ses, size, data, v9ses->maxdata,
+				     rcall, rcalllen);
+
+	kfree(data);
+
+	if (res < 0)
+		return res;
+
+	return 0;
+}
+
+/**
+ * v9fs_recv - receive an RPC response for a particular tag
+ * @v9ses: session info structure
+ * @req: RPC request structure
+ *
+ */
+
+static int v9fs_recv(struct v9fs_session_info *v9ses, struct v9fs_rpcreq *req)
+{
+	int ret = 0;
+
+	dprintk(DEBUG_MUX, "waiting for response: %d\n", req->tcall->tag);
+	ret = wait_event_interruptible(v9ses->read_wait,
+		       ((v9ses->transport->status != Connected) ||
+			(req->rcall != 0) || (req->err < 0) ||
+			dprintcond(v9ses, req)));
+
+	dprintk(DEBUG_MUX, "got it: rcall %p\n", req->rcall);
+
+	spin_lock(&v9ses->muxlock);
+	list_del(&req->next);
+	spin_unlock(&v9ses->muxlock);
+
+	if (req->err < 0)
+		return req->err;
+
+	if (v9ses->transport->status == Disconnected)
+		return -ECONNRESET;
+
+	return ret;
+}
+
+/**
+ * v9fs_send - send a 9P request
+ * @v9ses: session info structure
+ * @req: RPC request to send
+ *
+ */
+
+static int v9fs_send(struct v9fs_session_info *v9ses, struct v9fs_rpcreq *req)
+{
+	int ret = -1;
+	void *data = NULL;
+	struct v9fs_fcall *tcall = req->tcall;
+
+	data = kmalloc(v9ses->maxdata + V9FS_IOHDRSZ, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	tcall->size = 0;	/* enforce size recalculation */
+	ret =
+	    v9fs_serialize_fcall(v9ses, tcall, data,
+				 v9ses->maxdata + V9FS_IOHDRSZ);
+	if (ret < 0)
+		goto free_data;
+
+	spin_lock(&v9ses->muxlock);
+	list_add(&req->next, &v9ses->mux_fcalls);
+	spin_unlock(&v9ses->muxlock);
+
+	dprintk(DEBUG_MUX, "sending message: tag %d size %d\n", tcall->tag,
+		tcall->size);
+	ret = v9ses->transport->write(v9ses->transport, data, tcall->size);
+
+	if (ret != tcall->size) {
+		spin_lock(&v9ses->muxlock);
+		list_del(&req->next);
+		kfree(req->rcall);
+
+		spin_unlock(&v9ses->muxlock);
+		if (ret >= 0)
+			ret = -EREMOTEIO;
+	} else
+		ret = 0;
+
+      free_data:
+	kfree(data);
+	return ret;
+}
+
+/**
+ * v9fs_mux_rpc - send a request, receive a response
+ * @v9ses: session info structure
+ * @tcall: fcall to send
+ * @rcall: buffer to place response into
+ *
+ */
+
+long
+v9fs_mux_rpc(struct v9fs_session_info *v9ses, struct v9fs_fcall *tcall,
+	     struct v9fs_fcall **rcall)
+{
+	int tid = -1;
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_rpcreq req;
+	int ret = -1;
+
+	if (!v9ses)
+		return -EINVAL;
+
+	if (!v9ses->transport || v9ses->transport->status != Connected)
+		return -EIO;
+
+	if (rcall)
+		*rcall = NULL;
+
+	if (tcall->id != TVERSION) {
+		tid = v9fs_get_idpool(&v9ses->tidpool);
+		if (tid < 0)
+			return -ENOMEM;
+	}
+
+	tcall->tag = tid;
+
+	req.tcall = tcall;
+	req.err = 0;
+	req.rcall = NULL;
+
+	ret = v9fs_send(v9ses, &req);
+
+	if (ret < 0) {
+		if (tcall->id != TVERSION)
+			v9fs_put_idpool(tid, &v9ses->tidpool);
+		dprintk(DEBUG_MUX, "error %d\n", ret);
+		return ret;
+	}
+
+	ret = v9fs_recv(v9ses, &req);
+
+	fcall = req.rcall;
+
+	dprintk(DEBUG_MUX, "received: tag=%x, ret=%d\n", tcall->tag, ret);
+	if (ret == -ERESTARTSYS) {
+		if (v9ses->transport->status != Disconnected
+		    && tcall->id != TFLUSH) {
+			unsigned long flags;
+
+			dprintk(DEBUG_MUX, "flushing the tag: %d\n",
+				tcall->tag);
+			clear_thread_flag(TIF_SIGPENDING);
+			v9fs_t_flush(v9ses, tcall->tag);
+			spin_lock_irqsave(&current->sighand->siglock, flags);
+			recalc_sigpending();
+			spin_unlock_irqrestore(&current->sighand->siglock,
+					       flags);
+			dprintk(DEBUG_MUX, "flushing done\n");
+		}
+
+		goto release_req;
+	} else if (ret < 0)
+		goto release_req;
+
+	if (!fcall)
+		ret = -EIO;
+	else {
+		if (fcall->id == RERROR) {
+			ret = v9fs_errstr2errno(fcall->params.rerror.error);
+			if (ret == 0) {	/* string match failed */
+				if (fcall->params.rerror.errno)
+					ret = -(fcall->params.rerror.errno);
+				else
+					ret = -ESERVERFAULT;
+			}
+		} else if (fcall->id != tcall->id + 1) {
+			dprintk(DEBUG_ERROR,
+				"fcall mismatch: expected %d, got %d\n",
+				tcall->id + 1, fcall->id);
+			ret = -EIO;
+		}
+	}
+
+      release_req:
+	if (tcall->id != TVERSION)
+		v9fs_put_idpool(tid, &v9ses->tidpool);
+	if (rcall)
+		*rcall = fcall;
+	else
+		kfree(fcall);
+
+	return ret;
+}
+
+/**
+ * v9fs_mux_cancel_requests - cancels all pending requests
+ *
+ * @v9ses: session info structure
+ * @err: error code to return to the requests
+ */
+void v9fs_mux_cancel_requests(struct v9fs_session_info *v9ses, int err)
+{
+	struct v9fs_rpcreq *rptr;
+	struct v9fs_rpcreq *rreq;
+
+	dprintk(DEBUG_MUX, " %d\n", err);
+	spin_lock(&v9ses->muxlock);
+	list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
+		rreq->err = err;
+	}
+	spin_unlock(&v9ses->muxlock);
+	wake_up_all(&v9ses->read_wait);
+}
+
+/**
+ * v9fs_recvproc - kproc to handle demultiplexing responses
+ * @data: session info structure
+ *
+ */
+
+static int v9fs_recvproc(void *data)
+{
+	struct v9fs_session_info *v9ses = (struct v9fs_session_info *)data;
+	struct v9fs_fcall *rcall = NULL;
+	struct v9fs_rpcreq *rptr;
+	struct v9fs_rpcreq *req;
+	struct v9fs_rpcreq *rreq;
+	int err = 0;
+
+	allow_signal(SIGKILL);
+	set_current_state(TASK_INTERRUPTIBLE);
+	complete(&v9ses->proccmpl);
+	while (!kthread_should_stop() && err >= 0) {
+		req = rptr = rreq = NULL;
+
+		rcall = kmalloc(v9ses->maxdata + V9FS_IOHDRSZ, GFP_KERNEL);
+		if (!rcall) {
+			eprintk(KERN_ERR, "no memory for buffers\n");
+			break;
+		}
+
+		err = read_message(v9ses, rcall, v9ses->maxdata + V9FS_IOHDRSZ);
+		spin_lock(&v9ses->muxlock);
+		if (err < 0) {
+			list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
+				rreq->err = err;
+			}
+			if(err != -ERESTARTSYS)
+				eprintk(KERN_ERR,
+					"Transport error while reading message %d\n", err);
+		} else {
+			list_for_each_entry_safe(rreq, rptr, &v9ses->mux_fcalls, next) {
+				if (rreq->tcall->tag == rcall->tag) {
+					req = rreq;
+					req->rcall = rcall;
+					break;
+				}
+			}
+		}
+
+		if (req && (req->tcall->id == TFLUSH)) {
+			struct v9fs_rpcreq *treq = NULL;
+			list_for_each_entry_safe(treq, rptr, &v9ses->mux_fcalls, next) {
+				if (treq->tcall->tag ==
+				    req->tcall->params.tflush.oldtag) {
+					list_del(&rptr->next);
+					kfree(treq->rcall);
+					break;
+				}
+			}
+		}
+
+		spin_unlock(&v9ses->muxlock);
+
+		if (!req) {
+			if (err >= 0)
+				dprintk(DEBUG_ERROR,
+					"unexpected response: id %d tag %d\n",
+					rcall->id, rcall->tag);
+
+			kfree(rcall);
+		}
+
+		wake_up_all(&v9ses->read_wait);
+		set_current_state(TASK_INTERRUPTIBLE);
+	}
+
+	v9ses->transport->close(v9ses->transport);
+
+	/* Inform all pending processes about the failure */
+	wake_up_all(&v9ses->read_wait);
+
+	if (signal_pending(current))
+		complete(&v9ses->proccmpl);
+
+	dprintk(DEBUG_MUX, "recvproc: end\n");
+	v9ses->recvproc = NULL;
+
+	return err >= 0;
+}
+
+/**
+ * v9fs_mux_init - initialize multiplexer (spawn kproc)
+ * @v9ses: session info structure
+ * @dev_name: mount device information (to create unique kproc)
+ *
+ */
+
+int v9fs_mux_init(struct v9fs_session_info *v9ses, const char *dev_name)
+{
+	char procname[60];
+
+	strncpy(procname, dev_name, sizeof(procname));
+	procname[sizeof(procname) - 1] = 0;
+
+	init_waitqueue_head(&v9ses->read_wait);
+	init_completion(&v9ses->fcread);
+	init_completion(&v9ses->proccmpl);
+	spin_lock_init(&v9ses->muxlock);
+	INIT_LIST_HEAD(&v9ses->mux_fcalls);
+	v9ses->recvproc = NULL;
+	v9ses->curfcall = NULL;
+
+	v9ses->recvproc = kthread_create(v9fs_recvproc, v9ses,
+					 "v9fs_recvproc %s", procname);
+
+	if (IS_ERR(v9ses->recvproc)) {
+		eprintk(KERN_ERR, "cannot create receiving thread\n");
+		v9fs_session_close(v9ses);
+		return -ECONNABORTED;
+	}
+
+	wake_up_process(v9ses->recvproc);
+	wait_for_completion(&v9ses->proccmpl);
+
+	return 0;
+}
diff --git a/fs/9p/mux.h b/fs/9p/mux.h
new file mode 100644
index 00000000000..4994cb10bad
--- /dev/null
+++ b/fs/9p/mux.h
@@ -0,0 +1,41 @@
+/*
+ * linux/fs/9p/mux.h
+ *
+ * Multiplexer Definitions
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+/* structure to manage each RPC transaction */
+
+struct v9fs_rpcreq {
+	struct v9fs_fcall *tcall;
+	struct v9fs_fcall *rcall;
+	int err;	/* error code if response failed */
+
+	/* XXX - could we put scatter/gather buffers here? */
+
+	struct list_head next;
+};
+
+int v9fs_mux_init(struct v9fs_session_info *v9ses, const char *dev_name);
+long v9fs_mux_rpc(struct v9fs_session_info *v9ses,
+		  struct v9fs_fcall *tcall, struct v9fs_fcall **rcall);
+void v9fs_mux_cancel_requests(struct v9fs_session_info *v9ses, int err);
diff --git a/fs/9p/trans_fd.c b/fs/9p/trans_fd.c
new file mode 100644
index 00000000000..63b58ce98ff
--- /dev/null
+++ b/fs/9p/trans_fd.c
@@ -0,0 +1,172 @@
+/*
+ * linux/fs/9p/trans_fd.c
+ *
+ * File Descriptor Transport Layer
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/ipv6.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/un.h>
+#include <asm/uaccess.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <linux/file.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "transport.h"
+
+struct v9fs_trans_fd {
+	struct file *in_file;
+	struct file *out_file;
+};
+
+/**
+ * v9fs_fd_recv - receive from a socket
+ * @v9ses: session information
+ * @v: buffer to receive data into
+ * @len: size of receive buffer
+ *
+ */
+
+static int v9fs_fd_recv(struct v9fs_transport *trans, void *v, int len)
+{
+	struct v9fs_trans_fd *ts = trans ? trans->priv : NULL;
+
+	if (!trans || trans->status != Connected || !ts)
+		return -EIO;
+
+	return kernel_read(ts->in_file, ts->in_file->f_pos, v, len);
+}
+
+/**
+ * v9fs_fd_send - send to a socket
+ * @v9ses: session information
+ * @v: buffer to send data from
+ * @len: size of send buffer
+ *
+ */
+
+static int v9fs_fd_send(struct v9fs_transport *trans, void *v, int len)
+{
+	struct v9fs_trans_fd *ts = trans ? trans->priv : NULL;
+	mm_segment_t oldfs = get_fs();
+	int ret = 0;
+
+	if (!trans || trans->status != Connected || !ts)
+		return -EIO;
+
+	set_fs(get_ds());
+	/* The cast to a user pointer is valid due to the set_fs() */
+	ret = vfs_write(ts->out_file, (void __user *)v, len, &ts->out_file->f_pos);
+	set_fs(oldfs);
+
+	return ret;
+}
+
+/**
+ * v9fs_fd_init - initialize file descriptor transport
+ * @v9ses: session information
+ * @addr: address of server to mount
+ * @data: mount options
+ *
+ */
+
+static int
+v9fs_fd_init(struct v9fs_session_info *v9ses, const char *addr, char *data)
+{
+	struct v9fs_trans_fd *ts = NULL;
+	struct v9fs_transport *trans = v9ses->transport;
+
+	if((v9ses->wfdno == ~0) || (v9ses->rfdno == ~0)) {
+		printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n");
+		return -ENOPROTOOPT;
+	}
+
+	sema_init(&trans->writelock, 1);
+	sema_init(&trans->readlock, 1);
+
+	ts = kmalloc(sizeof(struct v9fs_trans_fd), GFP_KERNEL);
+
+	if (!ts)
+		return -ENOMEM;
+
+	ts->in_file = fget( v9ses->rfdno );
+	ts->out_file = fget( v9ses->wfdno );
+
+	if (!ts->in_file || !ts->out_file) {
+		if (ts->in_file)
+			fput(ts->in_file);
+
+		if (ts->out_file)
+			fput(ts->out_file);
+
+		kfree(ts);
+		return -EIO;
+	}
+
+	trans->priv = ts;
+	trans->status = Connected;
+
+	return 0;
+}
+
+
+/**
+ * v9fs_fd_close - shutdown file descriptor
+ * @trans: private socket structure
+ *
+ */
+
+static void v9fs_fd_close(struct v9fs_transport *trans)
+{
+	struct v9fs_trans_fd *ts;
+
+	if (!trans)
+		return;
+
+	trans->status = Disconnected;
+	ts = trans->priv;
+
+	if (!ts)
+		return;
+
+	if (ts->in_file)
+		fput(ts->in_file);
+
+	if (ts->out_file)
+		fput(ts->out_file);
+
+	kfree(ts);
+}
+
+struct v9fs_transport v9fs_trans_fd = {
+	.init = v9fs_fd_init,
+	.write = v9fs_fd_send,
+	.read = v9fs_fd_recv,
+	.close = v9fs_fd_close,
+};
+
diff --git a/fs/9p/trans_sock.c b/fs/9p/trans_sock.c
new file mode 100644
index 00000000000..01e26f0013a
--- /dev/null
+++ b/fs/9p/trans_sock.c
@@ -0,0 +1,290 @@
+/*
+ * linux/fs/9p/trans_socket.c
+ *
+ * Socket Transport Layer
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
+ *  Copyright (C) 1995, 1996 by Olaf Kirch <okir@monad.swb.de>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/ipv6.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/un.h>
+#include <asm/uaccess.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "transport.h"
+
+#define V9FS_PORT 564
+
+struct v9fs_trans_sock {
+	struct socket *s;
+};
+
+/**
+ * v9fs_sock_recv - receive from a socket
+ * @v9ses: session information
+ * @v: buffer to receive data into
+ * @len: size of receive buffer
+ *
+ */
+
+static int v9fs_sock_recv(struct v9fs_transport *trans, void *v, int len)
+{
+	struct msghdr msg;
+	struct kvec iov;
+	int result;
+	mm_segment_t oldfs;
+	struct v9fs_trans_sock *ts = trans ? trans->priv : NULL;
+
+	if (trans->status == Disconnected)
+		return -EREMOTEIO;
+
+	result = -EINVAL;
+
+	oldfs = get_fs();
+	set_fs(get_ds());
+
+	iov.iov_base = v;
+	iov.iov_len = len;
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_iovlen = 1;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_namelen = 0;
+	msg.msg_flags = MSG_NOSIGNAL;
+
+	result = kernel_recvmsg(ts->s, &msg, &iov, 1, len, 0);
+
+	dprintk(DEBUG_TRANS, "socket state %d\n", ts->s->state);
+	set_fs(oldfs);
+
+	if (result <= 0) {
+		if (result != -ERESTARTSYS)
+			trans->status = Disconnected;
+	}
+
+	return result;
+}
+
+/**
+ * v9fs_sock_send - send to a socket
+ * @v9ses: session information
+ * @v: buffer to send data from
+ * @len: size of send buffer
+ *
+ */
+
+static int v9fs_sock_send(struct v9fs_transport *trans, void *v, int len)
+{
+	struct kvec iov;
+	struct msghdr msg;
+	int result = -1;
+	mm_segment_t oldfs;
+	struct v9fs_trans_sock *ts = trans ? trans->priv : NULL;
+
+	dprintk(DEBUG_TRANS, "Sending packet size %d (%x)\n", len, len);
+	dump_data(v, len);
+
+	down(&trans->writelock);
+
+	oldfs = get_fs();
+	set_fs(get_ds());
+	iov.iov_base = v;
+	iov.iov_len = len;
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_iovlen = 1;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_namelen = 0;
+	msg.msg_flags = MSG_NOSIGNAL;
+	result = kernel_sendmsg(ts->s, &msg, &iov, 1, len);
+	set_fs(oldfs);
+
+	if (result < 0) {
+		if (result != -ERESTARTSYS)
+			trans->status = Disconnected;
+	}
+
+	up(&trans->writelock);
+	return result;
+}
+
+/**
+ * v9fs_tcp_init - initialize TCP socket
+ * @v9ses: session information
+ * @addr: address of server to mount
+ * @data: mount options
+ *
+ */
+
+static int
+v9fs_tcp_init(struct v9fs_session_info *v9ses, const char *addr, char *data)
+{
+	struct socket *csocket = NULL;
+	struct sockaddr_in sin_server;
+	int rc = 0;
+	struct v9fs_trans_sock *ts = NULL;
+	struct v9fs_transport *trans = v9ses->transport;
+
+	sema_init(&trans->writelock, 1);
+	sema_init(&trans->readlock, 1);
+
+	ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
+
+	if (!ts)
+		return -ENOMEM;
+
+	trans->priv = ts;
+	ts->s = NULL;
+
+	if (!addr)
+		return -EINVAL;
+
+	dprintk(DEBUG_TRANS, "Connecting to %s\n", addr);
+
+	sin_server.sin_family = AF_INET;
+	sin_server.sin_addr.s_addr = in_aton(addr);
+	sin_server.sin_port = htons(v9ses->port);
+	sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket);
+	rc = csocket->ops->connect(csocket,
+				   (struct sockaddr *)&sin_server,
+				   sizeof(struct sockaddr_in), 0);
+	if (rc < 0) {
+		eprintk(KERN_ERR,
+			"v9fs_trans_tcp: problem connecting socket to %s\n",
+			addr);
+		return rc;
+	}
+	csocket->sk->sk_allocation = GFP_NOIO;
+	ts->s = csocket;
+	trans->status = Connected;
+
+	return 0;
+}
+
+/**
+ * v9fs_unix_init - initialize UNIX domain socket
+ * @v9ses: session information
+ * @dev_name: path to named pipe
+ * @data: mount options
+ *
+ */
+
+static int
+v9fs_unix_init(struct v9fs_session_info *v9ses, const char *dev_name,
+	       char *data)
+{
+	int rc;
+	struct socket *csocket;
+	struct sockaddr_un sun_server;
+	struct v9fs_transport *trans;
+	struct v9fs_trans_sock *ts;
+
+	rc = 0;
+	csocket = NULL;
+	trans = v9ses->transport;
+
+	if (strlen(dev_name) > UNIX_PATH_MAX) {
+		eprintk(KERN_ERR, "v9fs_trans_unix: address too long: %s\n",
+			dev_name);
+		return -ENOMEM;
+	}
+
+	ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	trans->priv = ts;
+	ts->s = NULL;
+
+	sema_init(&trans->writelock, 1);
+	sema_init(&trans->readlock, 1);
+
+	sun_server.sun_family = PF_UNIX;
+	strcpy(sun_server.sun_path, dev_name);
+	sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket);
+	rc = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server,
+		sizeof(struct sockaddr_un) - 1, 0);	/* -1 *is* important */
+	if (rc < 0) {
+		eprintk(KERN_ERR,
+			"v9fs_trans_unix: problem connecting socket: %s: %d\n",
+			dev_name, rc);
+		return rc;
+	}
+	csocket->sk->sk_allocation = GFP_NOIO;
+	ts->s = csocket;
+	trans->status = Connected;
+
+	return 0;
+}
+
+/**
+ * v9fs_sock_close - shutdown socket
+ * @trans: private socket structure
+ *
+ */
+
+static void v9fs_sock_close(struct v9fs_transport *trans)
+{
+	struct v9fs_trans_sock *ts;
+
+	if (!trans)
+		return;
+
+	ts = trans->priv;
+
+	if ((ts) && (ts->s)) {
+		dprintk(DEBUG_TRANS, "closing the socket %p\n", ts->s);
+		sock_release(ts->s);
+		ts->s = NULL;
+		trans->status = Disconnected;
+		dprintk(DEBUG_TRANS, "socket closed\n");
+	}
+
+	if (ts)
+		kfree(ts);
+
+	trans->priv = NULL;
+}
+
+struct v9fs_transport v9fs_trans_tcp = {
+	.init = v9fs_tcp_init,
+	.write = v9fs_sock_send,
+	.read = v9fs_sock_recv,
+	.close = v9fs_sock_close,
+};
+
+struct v9fs_transport v9fs_trans_unix = {
+	.init = v9fs_unix_init,
+	.write = v9fs_sock_send,
+	.read = v9fs_sock_recv,
+	.close = v9fs_sock_close,
+};
diff --git a/fs/9p/transport.h b/fs/9p/transport.h
new file mode 100644
index 00000000000..9e9cd418efd
--- /dev/null
+++ b/fs/9p/transport.h
@@ -0,0 +1,46 @@
+/*
+ * linux/fs/9p/transport.h
+ *
+ * Transport Definition
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+enum v9fs_transport_status {
+	Connected,
+	Disconnected,
+	Hung,
+};
+
+struct v9fs_transport {
+	enum v9fs_transport_status status;
+	struct semaphore writelock;
+	struct semaphore readlock;
+	void *priv;
+
+	int (*init) (struct v9fs_session_info *, const char *, char *);
+	int (*write) (struct v9fs_transport *, void *, int);
+	int (*read) (struct v9fs_transport *, void *, int);
+	void (*close) (struct v9fs_transport *);
+};
+
+extern struct v9fs_transport v9fs_trans_tcp;
+extern struct v9fs_transport v9fs_trans_unix;
+extern struct v9fs_transport v9fs_trans_fd;
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
new file mode 100644
index 00000000000..13bdbbab438
--- /dev/null
+++ b/fs/9p/v9fs.c
@@ -0,0 +1,452 @@
+/*
+ *  linux/fs/9p/v9fs.c
+ *
+ *  This file contains functions assisting in mapping VFS to 9P2000
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/parser.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "transport.h"
+#include "mux.h"
+#include "conv.h"
+
+/* TODO: sysfs or debugfs interface */
+int v9fs_debug_level = 0;	/* feature-rific global debug level  */
+
+/*
+  * Option Parsing (code inspired by NFS code)
+  *
+  */
+
+enum {
+	/* Options that take integer arguments */
+	Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid, Opt_debug,
+	Opt_rfdno, Opt_wfdno,
+	/* String options */
+	Opt_name, Opt_remotename,
+	/* Options that take no arguments */
+	Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd,
+	/* Error token */
+	Opt_err
+};
+
+static match_table_t tokens = {
+	{Opt_port, "port=%u"},
+	{Opt_msize, "msize=%u"},
+	{Opt_uid, "uid=%u"},
+	{Opt_gid, "gid=%u"},
+	{Opt_afid, "afid=%u"},
+	{Opt_rfdno, "rfdno=%u"},
+	{Opt_wfdno, "wfdno=%u"},
+	{Opt_debug, "debug=%u"},
+	{Opt_name, "name=%s"},
+	{Opt_remotename, "aname=%s"},
+	{Opt_unix, "proto=unix"},
+	{Opt_tcp, "proto=tcp"},
+	{Opt_fd, "proto=fd"},
+	{Opt_tcp, "tcp"},
+	{Opt_unix, "unix"},
+	{Opt_fd, "fd"},
+	{Opt_legacy, "noextend"},
+	{Opt_nodevmap, "nodevmap"},
+	{Opt_err, NULL}
+};
+
+/*
+ *  Parse option string.
+ */
+
+/**
+ * v9fs_parse_options - parse mount options into session structure
+ * @options: options string passed from mount
+ * @v9ses: existing v9fs session information
+ *
+ */
+
+static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
+{
+	char *p;
+	substring_t args[MAX_OPT_ARGS];
+	int option;
+	int ret;
+
+	/* setup defaults */
+	v9ses->port = V9FS_PORT;
+	v9ses->maxdata = 9000;
+	v9ses->proto = PROTO_TCP;
+	v9ses->extended = 1;
+	v9ses->afid = ~0;
+	v9ses->debug = 0;
+	v9ses->rfdno = ~0;
+	v9ses->wfdno = ~0;
+
+	if (!options)
+		return;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token;
+		if (!*p)
+			continue;
+		token = match_token(p, tokens, args);
+		if (token < Opt_name) {
+			if ((ret = match_int(&args[0], &option)) < 0) {
+				dprintk(DEBUG_ERROR,
+					"integer field, but no integer?\n");
+				continue;
+			}
+
+		}
+		switch (token) {
+		case Opt_port:
+			v9ses->port = option;
+			break;
+		case Opt_msize:
+			v9ses->maxdata = option;
+			break;
+		case Opt_uid:
+			v9ses->uid = option;
+			break;
+		case Opt_gid:
+			v9ses->gid = option;
+			break;
+		case Opt_afid:
+			v9ses->afid = option;
+			break;
+		case Opt_rfdno:
+			v9ses->rfdno = option;
+			break;
+		case Opt_wfdno:
+			v9ses->wfdno = option;
+			break;
+		case Opt_debug:
+			v9ses->debug = option;
+			break;
+		case Opt_tcp:
+			v9ses->proto = PROTO_TCP;
+			break;
+		case Opt_unix:
+			v9ses->proto = PROTO_UNIX;
+			break;
+		case Opt_fd:
+			v9ses->proto = PROTO_FD;
+			break;
+		case Opt_name:
+			match_strcpy(v9ses->name, &args[0]);
+			break;
+		case Opt_remotename:
+			match_strcpy(v9ses->remotename, &args[0]);
+			break;
+		case Opt_legacy:
+			v9ses->extended = 0;
+			break;
+		case Opt_nodevmap:
+			v9ses->nodev = 1;
+			break;
+		default:
+			continue;
+		}
+	}
+}
+
+/**
+ * v9fs_inode2v9ses - safely extract v9fs session info from super block
+ * @inode: inode to extract information from
+ *
+ * Paranoid function to extract v9ses information from superblock,
+ * if anything is missing it will report an error.
+ *
+ */
+
+struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
+{
+	return (inode->i_sb->s_fs_info);
+}
+
+/**
+ * v9fs_get_idpool - allocate numeric id from pool
+ * @p - pool to allocate from
+ *
+ * XXX - This seems to be an awful generic function, should it be in idr.c with
+ *            the lock included in struct idr?
+ */
+
+int v9fs_get_idpool(struct v9fs_idpool *p)
+{
+	int i = 0;
+	int error;
+
+retry:
+	if (idr_pre_get(&p->pool, GFP_KERNEL) == 0)
+		return 0;
+
+	if (down_interruptible(&p->lock) == -EINTR) {
+		eprintk(KERN_WARNING, "Interrupted while locking\n");
+		return -1;
+	}
+
+	error = idr_get_new(&p->pool, NULL, &i);
+	up(&p->lock);
+
+	if (error == -EAGAIN)
+		goto retry;
+	else if (error)
+		return -1;
+
+	return i;
+}
+
+/**
+ * v9fs_put_idpool - release numeric id from pool
+ * @p - pool to allocate from
+ *
+ * XXX - This seems to be an awful generic function, should it be in idr.c with
+ *            the lock included in struct idr?
+ */
+
+void v9fs_put_idpool(int id, struct v9fs_idpool *p)
+{
+	if (down_interruptible(&p->lock) == -EINTR) {
+		eprintk(KERN_WARNING, "Interrupted while locking\n");
+		return;
+	}
+	idr_remove(&p->pool, id);
+	up(&p->lock);
+}
+
+/**
+ * v9fs_session_init - initialize session
+ * @v9ses: session information structure
+ * @dev_name: device being mounted
+ * @data: options
+ *
+ */
+
+int
+v9fs_session_init(struct v9fs_session_info *v9ses,
+		  const char *dev_name, char *data)
+{
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_transport *trans_proto;
+	int n = 0;
+	int newfid = -1;
+	int retval = -EINVAL;
+
+	v9ses->name = __getname();
+	if (!v9ses->name)
+		return -ENOMEM;
+
+	v9ses->remotename = __getname();
+	if (!v9ses->remotename) {
+		putname(v9ses->name);
+		return -ENOMEM;
+	}
+
+	strcpy(v9ses->name, V9FS_DEFUSER);
+	strcpy(v9ses->remotename, V9FS_DEFANAME);
+
+	v9fs_parse_options(data, v9ses);
+
+	/* set global debug level */
+	v9fs_debug_level = v9ses->debug;
+
+	/* id pools that are session-dependent: FIDs and TIDs */
+	idr_init(&v9ses->fidpool.pool);
+	init_MUTEX(&v9ses->fidpool.lock);
+	idr_init(&v9ses->tidpool.pool);
+	init_MUTEX(&v9ses->tidpool.lock);
+
+
+	switch (v9ses->proto) {
+	case PROTO_TCP:
+		trans_proto = &v9fs_trans_tcp;
+		break;
+	case PROTO_UNIX:
+		trans_proto = &v9fs_trans_unix;
+		*v9ses->remotename = 0;
+		break;
+	case PROTO_FD:
+		trans_proto = &v9fs_trans_fd;
+		*v9ses->remotename = 0;
+		break;
+	default:
+		printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
+		retval = -ENOPROTOOPT;
+		goto SessCleanUp;
+	};
+
+	v9ses->transport = trans_proto;
+
+	if ((retval = v9ses->transport->init(v9ses, dev_name, data)) < 0) {
+		eprintk(KERN_ERR, "problem initializing transport\n");
+		goto SessCleanUp;
+	}
+
+	v9ses->inprogress = 0;
+	v9ses->shutdown = 0;
+	v9ses->session_hung = 0;
+
+	if ((retval = v9fs_mux_init(v9ses, dev_name)) < 0) {
+		dprintk(DEBUG_ERROR, "problem initializing mux\n");
+		goto SessCleanUp;
+	}
+
+	if (v9ses->afid == ~0) {
+		if (v9ses->extended)
+			retval =
+			    v9fs_t_version(v9ses, v9ses->maxdata, "9P2000.u",
+					   &fcall);
+		else
+			retval = v9fs_t_version(v9ses, v9ses->maxdata, "9P2000",
+						&fcall);
+
+		if (retval < 0) {
+			dprintk(DEBUG_ERROR, "v9fs_t_version failed\n");
+			goto FreeFcall;
+		}
+
+		/* Really should check for 9P1 and report error */
+		if (!strcmp(fcall->params.rversion.version, "9P2000.u")) {
+			dprintk(DEBUG_9P, "9P2000 UNIX extensions enabled\n");
+			v9ses->extended = 1;
+		} else {
+			dprintk(DEBUG_9P, "9P2000 legacy mode enabled\n");
+			v9ses->extended = 0;
+		}
+
+		n = fcall->params.rversion.msize;
+		kfree(fcall);
+
+		if (n < v9ses->maxdata)
+			v9ses->maxdata = n;
+	}
+
+	newfid = v9fs_get_idpool(&v9ses->fidpool);
+	if (newfid < 0) {
+		eprintk(KERN_WARNING, "couldn't allocate FID\n");
+		retval = -ENOMEM;
+		goto SessCleanUp;
+	}
+	/* it is a little bit ugly, but we have to prevent newfid */
+	/* being the same as afid, so if it is, get a new fid     */
+	if (v9ses->afid != ~0 && newfid == v9ses->afid) {
+		newfid = v9fs_get_idpool(&v9ses->fidpool);
+		if (newfid < 0) {
+			eprintk(KERN_WARNING, "couldn't allocate FID\n");
+			retval = -ENOMEM;
+			goto SessCleanUp;
+		}
+	}
+
+	if ((retval =
+	     v9fs_t_attach(v9ses, v9ses->name, v9ses->remotename, newfid,
+			   v9ses->afid, NULL))
+	    < 0) {
+		dprintk(DEBUG_ERROR, "cannot attach\n");
+		goto SessCleanUp;
+	}
+
+	if (v9ses->afid != ~0) {
+		if (v9fs_t_clunk(v9ses, v9ses->afid, NULL))
+			dprintk(DEBUG_ERROR, "clunk failed\n");
+	}
+
+	return newfid;
+
+      FreeFcall:
+	kfree(fcall);
+
+      SessCleanUp:
+	v9fs_session_close(v9ses);
+	return retval;
+}
+
+/**
+ * v9fs_session_close - shutdown a session
+ * @v9ses: session information structure
+ *
+ */
+
+void v9fs_session_close(struct v9fs_session_info *v9ses)
+{
+	if (v9ses->recvproc) {
+		send_sig(SIGKILL, v9ses->recvproc, 1);
+		wait_for_completion(&v9ses->proccmpl);
+	}
+
+	if (v9ses->transport)
+		v9ses->transport->close(v9ses->transport);
+
+	putname(v9ses->name);
+	putname(v9ses->remotename);
+}
+
+/**
+ * v9fs_session_cancel - mark transport as disconnected
+ * 	and cancel all pending requests.
+ */
+void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
+	v9ses->transport->status = Disconnected;
+	v9fs_mux_cancel_requests(v9ses, -EIO);
+}
+
+extern int v9fs_error_init(void);
+
+/**
+ * v9fs_init - Initialize module
+ *
+ */
+
+static int __init init_v9fs(void)
+{
+	v9fs_error_init();
+
+	printk(KERN_INFO "Installing v9fs 9P2000 file system support\n");
+
+	return register_filesystem(&v9fs_fs_type);
+}
+
+/**
+ * v9fs_init - shutdown module
+ *
+ */
+
+static void __exit exit_v9fs(void)
+{
+	unregister_filesystem(&v9fs_fs_type);
+}
+
+module_init(init_v9fs)
+module_exit(exit_v9fs)
+
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
+MODULE_LICENSE("GPL");
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
new file mode 100644
index 00000000000..45dcef42bdd
--- /dev/null
+++ b/fs/9p/v9fs.h
@@ -0,0 +1,103 @@
+/*
+ * V9FS definitions.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+/*
+  * Idpool structure provides lock and id management
+  *
+  */
+
+struct v9fs_idpool {
+	struct semaphore lock;
+	struct idr pool;
+};
+
+/*
+  * Session structure provides information for an opened session
+  *
+  */
+
+struct v9fs_session_info {
+	/* options */
+	unsigned int maxdata;
+	unsigned char extended;	/* set to 1 if we are using UNIX extensions */
+	unsigned char nodev;	/* set to 1 if no disable device mapping */
+	unsigned short port;	/* port to connect to */
+	unsigned short debug;	/* debug level */
+	unsigned short proto;	/* protocol to use */
+	unsigned int afid;	/* authentication fid */
+	unsigned int rfdno;	/* read file descriptor number */
+	unsigned int wfdno;	/* write file descriptor number */
+
+
+	char *name;		/* user name to mount as */
+	char *remotename;	/* name of remote hierarchy being mounted */
+	unsigned int uid;	/* default uid/muid for legacy support */
+	unsigned int gid;	/* default gid for legacy support */
+
+	/* book keeping */
+	struct v9fs_idpool fidpool;	/* The FID pool for file descriptors */
+	struct v9fs_idpool tidpool;	/* The TID pool for transactions ids */
+
+	/* transport information */
+	struct v9fs_transport *transport;
+
+	int inprogress;		/* session in progress => true */
+	int shutdown;		/* session shutting down. no more attaches. */
+	unsigned char session_hung;
+
+	/* mux private data */
+	struct v9fs_fcall *curfcall;
+	wait_queue_head_t read_wait;
+	struct completion fcread;
+	struct completion proccmpl;
+	struct task_struct *recvproc;
+
+	spinlock_t muxlock;
+	struct list_head mux_fcalls;
+};
+
+/* possible values of ->proto */
+enum {
+	PROTO_TCP,
+	PROTO_UNIX,
+	PROTO_FD,
+};
+
+int v9fs_session_init(struct v9fs_session_info *, const char *, char *);
+struct v9fs_session_info *v9fs_inode2v9ses(struct inode *);
+void v9fs_session_close(struct v9fs_session_info *v9ses);
+int v9fs_get_idpool(struct v9fs_idpool *p);
+void v9fs_put_idpool(int id, struct v9fs_idpool *p);
+void v9fs_session_cancel(struct v9fs_session_info *v9ses);
+
+#define V9FS_MAGIC 0x01021997
+
+/* other default globals */
+#define V9FS_PORT		564
+#define V9FS_DEFUSER	"nobody"
+#define V9FS_DEFANAME	""
+
+/* inital pool sizes for fids and tags */
+#define V9FS_START_FIDS 8192
+#define V9FS_START_TIDS 256
diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
new file mode 100644
index 00000000000..2f2cea7ee3e
--- /dev/null
+++ b/fs/9p/v9fs_vfs.h
@@ -0,0 +1,53 @@
+/*
+ * V9FS VFS extensions.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+/* plan9 semantics are that created files are implicitly opened.
+ * But linux semantics are that you call create, then open.
+ * the plan9 approach is superior as it provides an atomic
+ * open.
+ * we track the create fid here. When the file is opened, if fidopen is
+ * non-zero, we use the fid and can skip some steps.
+ * there may be a better way to do this, but I don't know it.
+ * one BAD way is to clunk the fid on create, then open it again:
+ * you lose the atomicity of file open
+ */
+
+/* special case:
+ * unlink calls remove, which is an implicit clunk. So we have to track
+ * that kind of thing so that we don't try to clunk a dead fid.
+ */
+
+extern struct file_system_type v9fs_fs_type;
+extern struct file_operations v9fs_file_operations;
+extern struct file_operations v9fs_dir_operations;
+extern struct dentry_operations v9fs_dentry_operations;
+
+struct inode *v9fs_get_inode(struct super_block *sb, int mode);
+ino_t v9fs_qid2ino(struct v9fs_qid *qid);
+void v9fs_mistat2inode(struct v9fs_stat *, struct inode *,
+		       struct super_block *);
+int v9fs_dir_release(struct inode *inode, struct file *filp);
+int v9fs_file_open(struct inode *inode, struct file *file);
+void v9fs_inode2mistat(struct inode *inode, struct v9fs_stat *mistat);
+void v9fs_dentry_release(struct dentry *);
diff --git a/fs/9p/vfs_dentry.c b/fs/9p/vfs_dentry.c
new file mode 100644
index 00000000000..306c96741f8
--- /dev/null
+++ b/fs/9p/vfs_dentry.c
@@ -0,0 +1,126 @@
+/*
+ *  linux/fs/9p/vfs_dentry.c
+ *
+ * This file contians vfs dentry ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+#include <linux/inet.h>
+#include <linux/namei.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "conv.h"
+#include "fid.h"
+
+/**
+ * v9fs_dentry_validate - VFS dcache hook to validate cache
+ * @dentry:  dentry that is being validated
+ * @nd: path data
+ *
+ * dcache really shouldn't be used for 9P2000 as at all due to
+ * potential attached semantics to directory traversal (walk).
+ *
+ * FUTURE: look into how to use dcache to allow multi-stage
+ * walks in Plan 9 & potential for better dcache operation which
+ * would remain valid for Plan 9 semantics.  Older versions
+ * had validation via stat for those interested.  However, since
+ * stat has the same approximate overhead as walk there really
+ * is no difference.  The only improvement would be from a
+ * time-decay cache like NFS has and that undermines the
+ * synchronous nature of 9P2000.
+ *
+ */
+
+static int v9fs_dentry_validate(struct dentry *dentry, struct nameidata *nd)
+{
+	struct dentry *dc = current->fs->pwd;
+
+	dprintk(DEBUG_VFS, "dentry: %s (%p)\n", dentry->d_iname, dentry);
+	if (v9fs_fid_lookup(dentry, FID_OP)) {
+		dprintk(DEBUG_VFS, "VALID\n");
+		return 1;
+	}
+
+	while (dc != NULL) {
+		if (dc == dentry) {
+			dprintk(DEBUG_VFS, "VALID\n");
+			return 1;
+		}
+		if (dc == dc->d_parent)
+			break;
+
+		dc = dc->d_parent;
+	}
+
+	dprintk(DEBUG_VFS, "INVALID\n");
+	return 0;
+}
+
+/**
+ * v9fs_dentry_release - called when dentry is going to be freed
+ * @dentry:  dentry that is being release
+ *
+ */
+
+void v9fs_dentry_release(struct dentry *dentry)
+{
+	dprintk(DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);
+
+	if (dentry->d_fsdata != NULL) {
+		struct list_head *fid_list = dentry->d_fsdata;
+		struct v9fs_fid *temp = NULL;
+		struct v9fs_fid *current_fid = NULL;
+		struct v9fs_fcall *fcall = NULL;
+
+		list_for_each_entry_safe(current_fid, temp, fid_list, list) {
+			if (v9fs_t_clunk
+			    (current_fid->v9ses, current_fid->fid, &fcall))
+				dprintk(DEBUG_ERROR, "clunk failed: %s\n",
+					FCALL_ERROR(fcall));
+
+			v9fs_put_idpool(current_fid->fid,
+					&current_fid->v9ses->fidpool);
+
+			kfree(fcall);
+			v9fs_fid_destroy(current_fid);
+		}
+
+		kfree(dentry->d_fsdata);	/* free the list_head */
+	}
+}
+
+struct dentry_operations v9fs_dentry_operations = {
+	.d_revalidate = v9fs_dentry_validate,
+	.d_release = v9fs_dentry_release,
+};
diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
new file mode 100644
index 00000000000..c478a738418
--- /dev/null
+++ b/fs/9p/vfs_dir.c
@@ -0,0 +1,226 @@
+/*
+ * linux/fs/9p/vfs_dir.c
+ *
+ * This file contains vfs directory ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "conv.h"
+#include "fid.h"
+
+/**
+ * dt_type - return file type
+ * @mistat: mistat structure
+ *
+ */
+
+static inline int dt_type(struct v9fs_stat *mistat)
+{
+	unsigned long perm = mistat->mode;
+	int rettype = DT_REG;
+
+	if (perm & V9FS_DMDIR)
+		rettype = DT_DIR;
+	if (perm & V9FS_DMSYMLINK)
+		rettype = DT_LNK;
+
+	return rettype;
+}
+
+/**
+ * v9fs_dir_readdir - read a directory
+ * @filep: opened file structure
+ * @dirent: directory structure ???
+ * @filldir: function to populate directory structure ???
+ *
+ */
+
+static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+	struct v9fs_fcall *fcall = NULL;
+	struct inode *inode = filp->f_dentry->d_inode;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
+	struct v9fs_fid *file = filp->private_data;
+	unsigned int i, n;
+	int fid = -1;
+	int ret = 0;
+	struct v9fs_stat *mi = NULL;
+	int over = 0;
+
+	dprintk(DEBUG_VFS, "name %s\n", filp->f_dentry->d_name.name);
+
+	fid = file->fid;
+
+	mi = kmalloc(v9ses->maxdata, GFP_KERNEL);
+	if (!mi)
+		return -ENOMEM;
+
+	if (file->rdir_fcall && (filp->f_pos != file->rdir_pos)) {
+		kfree(file->rdir_fcall);
+		file->rdir_fcall = NULL;
+	}
+
+	if (file->rdir_fcall) {
+		n = file->rdir_fcall->params.rread.count;
+		i = file->rdir_fpos;
+		while (i < n) {
+			int s = v9fs_deserialize_stat(v9ses,
+				  file->rdir_fcall->params.rread.data + i,
+			          n - i, mi, v9ses->maxdata);
+
+			if (s == 0) {
+				dprintk(DEBUG_ERROR,
+					"error while deserializing mistat\n");
+				ret = -EIO;
+				goto FreeStructs;
+			}
+
+			over = filldir(dirent, mi->name, strlen(mi->name),
+				    filp->f_pos, v9fs_qid2ino(&mi->qid),
+				    dt_type(mi));
+
+			if (over) {
+				file->rdir_fpos = i;
+				file->rdir_pos = filp->f_pos;
+				break;
+			}
+
+			i += s;
+			filp->f_pos += s;
+		}
+
+		if (!over) {
+			kfree(file->rdir_fcall);
+			file->rdir_fcall = NULL;
+		}
+	}
+
+	while (!over) {
+		ret = v9fs_t_read(v9ses, fid, filp->f_pos,
+					    v9ses->maxdata-V9FS_IOHDRSZ, &fcall);
+		if (ret < 0) {
+			dprintk(DEBUG_ERROR, "error while reading: %d: %p\n",
+				ret, fcall);
+			goto FreeStructs;
+		} else if (ret == 0)
+			break;
+
+		n = ret;
+		i = 0;
+		while (i < n) {
+			int s = v9fs_deserialize_stat(v9ses,
+			          fcall->params.rread.data + i, n - i, mi,
+			          v9ses->maxdata);
+
+			if (s == 0) {
+				dprintk(DEBUG_ERROR,
+					"error while deserializing mistat\n");
+				return -EIO;
+			}
+
+			over = filldir(dirent, mi->name, strlen(mi->name),
+				    filp->f_pos, v9fs_qid2ino(&mi->qid),
+				    dt_type(mi));
+
+			if (over) {
+				file->rdir_fcall = fcall;
+				file->rdir_fpos = i;
+				file->rdir_pos = filp->f_pos;
+				fcall = NULL;
+				break;
+			}
+
+			i += s;
+			filp->f_pos += s;
+		}
+
+		kfree(fcall);
+	}
+
+      FreeStructs:
+	kfree(fcall);
+	kfree(mi);
+	return ret;
+}
+
+/**
+ * v9fs_dir_release - close a directory
+ * @inode: inode of the directory
+ * @filp: file pointer to a directory
+ *
+ */
+
+int v9fs_dir_release(struct inode *inode, struct file *filp)
+{
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
+	struct v9fs_fid *fid = filp->private_data;
+	int fidnum = -1;
+
+	dprintk(DEBUG_VFS, "inode: %p filp: %p fid: %d\n", inode, filp,
+		fid->fid);
+	fidnum = fid->fid;
+
+	filemap_fdatawrite(inode->i_mapping);
+	filemap_fdatawait(inode->i_mapping);
+
+	if (fidnum >= 0) {
+		fid->fidopen--;
+		dprintk(DEBUG_VFS, "fidopen: %d v9f->fid: %d\n", fid->fidopen,
+			fid->fid);
+
+		if (fid->fidopen == 0) {
+			if (v9fs_t_clunk(v9ses, fidnum, NULL))
+				dprintk(DEBUG_ERROR, "clunk failed\n");
+
+			v9fs_put_idpool(fid->fid, &v9ses->fidpool);
+		}
+
+		kfree(fid->rdir_fcall);
+
+		filp->private_data = NULL;
+		v9fs_fid_destroy(fid);
+	}
+
+	d_drop(filp->f_dentry);
+	return 0;
+}
+
+struct file_operations v9fs_dir_operations = {
+	.read = generic_read_dir,
+	.readdir = v9fs_dir_readdir,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+};
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
new file mode 100644
index 00000000000..1f8ae7d580a
--- /dev/null
+++ b/fs/9p/vfs_file.c
@@ -0,0 +1,401 @@
+/*
+ *  linux/fs/9p/vfs_file.c
+ *
+ * This file contians vfs file ops for 9P2000.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+#include <linux/inet.h>
+#include <linux/version.h>
+#include <linux/list.h>
+#include <asm/uaccess.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * v9fs_file_open - open a file (or directory)
+ * @inode: inode to be opened
+ * @file: file being opened
+ *
+ */
+
+int v9fs_file_open(struct inode *inode, struct file *file)
+{
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
+	struct v9fs_fid *v9fid = v9fs_fid_lookup(file->f_dentry, FID_WALK);
+	struct v9fs_fid *v9newfid = NULL;
+	struct v9fs_fcall *fcall = NULL;
+	int open_mode = 0;
+	unsigned int iounit = 0;
+	int newfid = -1;
+	long result = -1;
+
+	dprintk(DEBUG_VFS, "inode: %p file: %p v9fid= %p\n", inode, file,
+		v9fid);
+
+	if (!v9fid) {
+		struct dentry *dentry = file->f_dentry;
+		dprintk(DEBUG_ERROR, "Couldn't resolve fid from dentry\n");
+
+		/* XXX - some duplication from lookup, generalize later */
+		/* basically vfs_lookup is too heavy weight */
+		v9fid = v9fs_fid_lookup(file->f_dentry, FID_OP);
+		if (!v9fid)
+			return -EBADF;
+
+		v9fid = v9fs_fid_lookup(dentry->d_parent, FID_WALK);
+		if (!v9fid)
+			return -EBADF;
+
+		newfid = v9fs_get_idpool(&v9ses->fidpool);
+		if (newfid < 0) {
+			eprintk(KERN_WARNING, "newfid fails!\n");
+			return -ENOSPC;
+		}
+
+		result =
+		    v9fs_t_walk(v9ses, v9fid->fid, newfid,
+				(char *)file->f_dentry->d_name.name, NULL);
+		if (result < 0) {
+			v9fs_put_idpool(newfid, &v9ses->fidpool);
+			dprintk(DEBUG_ERROR, "rewalk didn't work\n");
+			return -EBADF;
+		}
+
+		v9fid = v9fs_fid_create(dentry);
+		if (v9fid == NULL) {
+			dprintk(DEBUG_ERROR, "couldn't insert\n");
+			return -ENOMEM;
+		}
+		v9fid->fid = newfid;
+	}
+
+	if (v9fid->fidcreate) {
+		/* create case */
+		newfid = v9fid->fid;
+		iounit = v9fid->iounit;
+		v9fid->fidcreate = 0;
+	} else {
+		if (!S_ISDIR(inode->i_mode))
+			newfid = v9fid->fid;
+		else {
+			newfid = v9fs_get_idpool(&v9ses->fidpool);
+			if (newfid < 0) {
+				eprintk(KERN_WARNING, "allocation failed\n");
+				return -ENOSPC;
+			}
+			/* This would be a somewhat critical clone */
+			result =
+			    v9fs_t_walk(v9ses, v9fid->fid, newfid, NULL,
+					&fcall);
+			if (result < 0) {
+				dprintk(DEBUG_ERROR, "clone error: %s\n",
+					FCALL_ERROR(fcall));
+				kfree(fcall);
+				return result;
+			}
+
+			v9newfid = v9fs_fid_create(file->f_dentry);
+			v9newfid->fid = newfid;
+			v9newfid->qid = v9fid->qid;
+			v9newfid->iounit = v9fid->iounit;
+			v9newfid->fidopen = 0;
+			v9newfid->fidclunked = 0;
+			v9newfid->v9ses = v9ses;
+			v9fid = v9newfid;
+			kfree(fcall);
+		}
+
+		/* TODO: do special things for O_EXCL, O_NOFOLLOW, O_SYNC */
+		/* translate open mode appropriately */
+		open_mode = file->f_flags & 0x3;
+
+		if (file->f_flags & O_EXCL)
+			open_mode |= V9FS_OEXCL;
+
+		if (v9ses->extended) {
+			if (file->f_flags & O_TRUNC)
+				open_mode |= V9FS_OTRUNC;
+
+			if (file->f_flags & O_APPEND)
+				open_mode |= V9FS_OAPPEND;
+		}
+
+		result = v9fs_t_open(v9ses, newfid, open_mode, &fcall);
+		if (result < 0) {
+			dprintk(DEBUG_ERROR,
+				"open failed, open_mode 0x%x: %s\n", open_mode,
+				FCALL_ERROR(fcall));
+			kfree(fcall);
+			return result;
+		}
+
+		iounit = fcall->params.ropen.iounit;
+		kfree(fcall);
+	}
+
+
+	file->private_data = v9fid;
+
+	v9fid->rdir_pos = 0;
+	v9fid->rdir_fcall = NULL;
+	v9fid->fidopen = 1;
+	v9fid->filp = file;
+	v9fid->iounit = iounit;
+
+	return 0;
+}
+
+/**
+ * v9fs_file_lock - lock a file (or directory)
+ * @inode: inode to be opened
+ * @file: file being opened
+ *
+ * XXX - this looks like a local only lock, we should extend into 9P
+ *       by using open exclusive
+ */
+
+static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	int res = 0;
+	struct inode *inode = filp->f_dentry->d_inode;
+
+	dprintk(DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
+
+	/* No mandatory locks */
+	if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
+		return -ENOLCK;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_fdatawrite(inode->i_mapping);
+		filemap_fdatawait(inode->i_mapping);
+		invalidate_inode_pages(&inode->i_data);
+	}
+
+	return res;
+}
+
+/**
+ * v9fs_read - read from a file (internal)
+ * @filep: file pointer to read
+ * @data: data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+
+static ssize_t
+v9fs_read(struct file *filp, char *buffer, size_t count, loff_t * offset)
+{
+	struct inode *inode = filp->f_dentry->d_inode;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
+	struct v9fs_fid *v9f = filp->private_data;
+	struct v9fs_fcall *fcall = NULL;
+	int fid = v9f->fid;
+	int rsize = 0;
+	int result = 0;
+	int total = 0;
+
+	dprintk(DEBUG_VFS, "\n");
+
+	rsize = v9ses->maxdata - V9FS_IOHDRSZ;
+	if (v9f->iounit != 0 && rsize > v9f->iounit)
+		rsize = v9f->iounit;
+
+	do {
+		if (count < rsize)
+			rsize = count;
+
+		result = v9fs_t_read(v9ses, fid, *offset, rsize, &fcall);
+
+		if (result < 0) {
+			printk(KERN_ERR "9P2000: v9fs_t_read returned %d\n",
+			       result);
+
+			kfree(fcall);
+			return total;
+		} else
+			*offset += result;
+
+		/* XXX - extra copy */
+		memcpy(buffer, fcall->params.rread.data, result);
+		count -= result;
+		buffer += result;
+		total += result;
+
+		kfree(fcall);
+
+		if (result < rsize)
+			break;
+	} while (count);
+
+	return total;
+}
+
+/**
+ * v9fs_file_read - read from a file
+ * @filep: file pointer to read
+ * @data: data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+
+static ssize_t
+v9fs_file_read(struct file *filp, char __user * data, size_t count,
+	       loff_t * offset)
+{
+	int retval = -1;
+	int ret = 0;
+	char *buffer;
+
+	buffer = kmalloc(count, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+
+	retval = v9fs_read(filp, buffer, count, offset);
+	if (retval > 0) {
+		if ((ret = copy_to_user(data, buffer, retval)) != 0) {
+			dprintk(DEBUG_ERROR, "Problem copying to user %d\n",
+				ret);
+			retval = ret;
+		}
+	}
+
+	kfree(buffer);
+
+	return retval;
+}
+
+/**
+ * v9fs_write - write to a file
+ * @filep: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+
+static ssize_t
+v9fs_write(struct file *filp, char *buffer, size_t count, loff_t * offset)
+{
+	struct inode *inode = filp->f_dentry->d_inode;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
+	struct v9fs_fid *v9fid = filp->private_data;
+	struct v9fs_fcall *fcall;
+	int fid = v9fid->fid;
+	int result = -EIO;
+	int rsize = 0;
+	int total = 0;
+
+	dprintk(DEBUG_VFS, "data %p count %d offset %x\n", buffer, (int)count,
+		(int)*offset);
+	rsize = v9ses->maxdata - V9FS_IOHDRSZ;
+	if (v9fid->iounit != 0 && rsize > v9fid->iounit)
+		rsize = v9fid->iounit;
+
+	dump_data(buffer, count);
+
+	do {
+		if (count < rsize)
+			rsize = count;
+
+		result =
+		    v9fs_t_write(v9ses, fid, *offset, rsize, buffer, &fcall);
+		if (result < 0) {
+			eprintk(KERN_ERR, "error while writing: %s(%d)\n",
+				FCALL_ERROR(fcall), result);
+			kfree(fcall);
+			return result;
+		} else
+			*offset += result;
+
+		kfree(fcall);
+
+		if (result != rsize) {
+			eprintk(KERN_ERR,
+				"short write: v9fs_t_write returned %d\n",
+				result);
+			break;
+		}
+
+		count -= result;
+		buffer += result;
+		total += result;
+	} while (count);
+
+	return total;
+}
+
+/**
+ * v9fs_file_write - write to a file
+ * @filep: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+
+static ssize_t
+v9fs_file_write(struct file *filp, const char __user * data,
+		size_t count, loff_t * offset)
+{
+	int ret = -1;
+	char *buffer;
+
+	buffer = kmalloc(count, GFP_KERNEL);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	ret = copy_from_user(buffer, data, count);
+	if (ret) {
+		dprintk(DEBUG_ERROR, "Problem copying from user\n");
+		ret = -EFAULT;
+	} else {
+		ret = v9fs_write(filp, buffer, count, offset);
+	}
+
+	kfree(buffer);
+
+	return ret;
+}
+
+struct file_operations v9fs_file_operations = {
+	.llseek = generic_file_llseek,
+	.read = v9fs_file_read,
+	.write = v9fs_file_write,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+};
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
new file mode 100644
index 00000000000..0c13fc60004
--- /dev/null
+++ b/fs/9p/vfs_inode.c
@@ -0,0 +1,1338 @@
+/*
+ *  linux/fs/9p/vfs_inode.c
+ *
+ * This file contains vfs inode ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+#include <linux/inet.h>
+#include <linux/namei.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "conv.h"
+#include "fid.h"
+
+static struct inode_operations v9fs_dir_inode_operations;
+static struct inode_operations v9fs_dir_inode_operations_ext;
+static struct inode_operations v9fs_file_inode_operations;
+static struct inode_operations v9fs_symlink_inode_operations;
+
+/**
+ * unixmode2p9mode - convert unix mode bits to plan 9
+ * @v9ses: v9fs session information
+ * @mode: mode to convert
+ *
+ */
+
+static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
+{
+	int res;
+	res = mode & 0777;
+	if (S_ISDIR(mode))
+		res |= V9FS_DMDIR;
+	if (v9ses->extended) {
+		if (S_ISLNK(mode))
+			res |= V9FS_DMSYMLINK;
+		if (v9ses->nodev == 0) {
+			if (S_ISSOCK(mode))
+				res |= V9FS_DMSOCKET;
+			if (S_ISFIFO(mode))
+				res |= V9FS_DMNAMEDPIPE;
+			if (S_ISBLK(mode))
+				res |= V9FS_DMDEVICE;
+			if (S_ISCHR(mode))
+				res |= V9FS_DMDEVICE;
+		}
+
+		if ((mode & S_ISUID) == S_ISUID)
+			res |= V9FS_DMSETUID;
+		if ((mode & S_ISGID) == S_ISGID)
+			res |= V9FS_DMSETGID;
+		if ((mode & V9FS_DMLINK))
+			res |= V9FS_DMLINK;
+	}
+
+	return res;
+}
+
+/**
+ * p9mode2unixmode- convert plan9 mode bits to unix mode bits
+ * @v9ses: v9fs session information
+ * @mode: mode to convert
+ *
+ */
+
+static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
+{
+	int res;
+
+	res = mode & 0777;
+
+	if ((mode & V9FS_DMDIR) == V9FS_DMDIR)
+		res |= S_IFDIR;
+	else if ((mode & V9FS_DMSYMLINK) && (v9ses->extended))
+		res |= S_IFLNK;
+	else if ((mode & V9FS_DMSOCKET) && (v9ses->extended)
+		 && (v9ses->nodev == 0))
+		res |= S_IFSOCK;
+	else if ((mode & V9FS_DMNAMEDPIPE) && (v9ses->extended)
+		 && (v9ses->nodev == 0))
+		res |= S_IFIFO;
+	else if ((mode & V9FS_DMDEVICE) && (v9ses->extended)
+		 && (v9ses->nodev == 0))
+		res |= S_IFBLK;
+	else
+		res |= S_IFREG;
+
+	if (v9ses->extended) {
+		if ((mode & V9FS_DMSETUID) == V9FS_DMSETUID)
+			res |= S_ISUID;
+
+		if ((mode & V9FS_DMSETGID) == V9FS_DMSETGID)
+			res |= S_ISGID;
+	}
+
+	return res;
+}
+
+/**
+ * v9fs_blank_mistat - helper function to setup a 9P stat structure
+ * @v9ses: 9P session info (for determining extended mode)
+ * @mistat: structure to initialize
+ *
+ */
+
+static void
+v9fs_blank_mistat(struct v9fs_session_info *v9ses, struct v9fs_stat *mistat)
+{
+	mistat->type = ~0;
+	mistat->dev = ~0;
+	mistat->qid.type = ~0;
+	mistat->qid.version = ~0;
+	*((long long *)&mistat->qid.path) = ~0;
+	mistat->mode = ~0;
+	mistat->atime = ~0;
+	mistat->mtime = ~0;
+	mistat->length = ~0;
+	mistat->name = mistat->data;
+	mistat->uid = mistat->data;
+	mistat->gid = mistat->data;
+	mistat->muid = mistat->data;
+	if (v9ses->extended) {
+		mistat->n_uid = ~0;
+		mistat->n_gid = ~0;
+		mistat->n_muid = ~0;
+		mistat->extension = mistat->data;
+	}
+	*mistat->data = 0;
+}
+
+/**
+ * v9fs_mistat2unix - convert mistat to unix stat
+ * @mistat: Plan 9 metadata (mistat) structure
+ * @buf: unix metadata (stat) structure to populate
+ * @sb: superblock
+ *
+ */
+
+static void
+v9fs_mistat2unix(struct v9fs_stat *mistat, struct stat *buf,
+		 struct super_block *sb)
+{
+	struct v9fs_session_info *v9ses = sb ? sb->s_fs_info : NULL;
+
+	buf->st_nlink = 1;
+
+	buf->st_atime = mistat->atime;
+	buf->st_mtime = mistat->mtime;
+	buf->st_ctime = mistat->mtime;
+
+	buf->st_uid = (unsigned short)-1;
+	buf->st_gid = (unsigned short)-1;
+
+	if (v9ses && v9ses->extended) {
+		/* TODO: string to uid mapping via user-space daemon */
+		if (mistat->n_uid != -1)
+			sscanf(mistat->uid, "%x", (unsigned int *)&buf->st_uid);
+
+		if (mistat->n_gid != -1)
+			sscanf(mistat->gid, "%x", (unsigned int *)&buf->st_gid);
+	}
+
+	if (buf->st_uid == (unsigned short)-1)
+		buf->st_uid = v9ses->uid;
+	if (buf->st_gid == (unsigned short)-1)
+		buf->st_gid = v9ses->gid;
+
+	buf->st_mode = p9mode2unixmode(v9ses, mistat->mode);
+	if ((S_ISBLK(buf->st_mode)) || (S_ISCHR(buf->st_mode))) {
+		char type = 0;
+		int major = -1;
+		int minor = -1;
+		sscanf(mistat->extension, "%c %u %u", &type, &major, &minor);
+		switch (type) {
+		case 'c':
+			buf->st_mode &= ~S_IFBLK;
+			buf->st_mode |= S_IFCHR;
+			break;
+		case 'b':
+			break;
+		default:
+			dprintk(DEBUG_ERROR, "Unknown special type %c (%s)\n",
+				type, mistat->extension);
+		};
+		buf->st_rdev = MKDEV(major, minor);
+	} else
+		buf->st_rdev = 0;
+
+	buf->st_size = mistat->length;
+
+	buf->st_blksize = sb->s_blocksize;
+	buf->st_blocks =
+	    (buf->st_size + buf->st_blksize - 1) >> sb->s_blocksize_bits;
+}
+
+/**
+ * v9fs_get_inode - helper function to setup an inode
+ * @sb: superblock
+ * @mode: mode to setup inode with
+ *
+ */
+
+struct inode *v9fs_get_inode(struct super_block *sb, int mode)
+{
+	struct inode *inode = NULL;
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+	dprintk(DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
+
+	inode = new_inode(sb);
+	if (inode) {
+		inode->i_mode = mode;
+		inode->i_uid = current->fsuid;
+		inode->i_gid = current->fsgid;
+		inode->i_blksize = sb->s_blocksize;
+		inode->i_blocks = 0;
+		inode->i_rdev = 0;
+		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+
+		switch (mode & S_IFMT) {
+		case S_IFIFO:
+		case S_IFBLK:
+		case S_IFCHR:
+		case S_IFSOCK:
+			if(!v9ses->extended) {
+				dprintk(DEBUG_ERROR, "special files without extended mode\n");
+				return ERR_PTR(-EINVAL);
+			}
+			init_special_inode(inode, inode->i_mode,
+					   inode->i_rdev);
+			break;
+		case S_IFREG:
+			inode->i_op = &v9fs_file_inode_operations;
+			inode->i_fop = &v9fs_file_operations;
+			break;
+		case S_IFLNK:
+			if(!v9ses->extended) {
+				dprintk(DEBUG_ERROR, "extended modes used w/o 9P2000.u\n");
+				return ERR_PTR(-EINVAL);
+			}
+			inode->i_op = &v9fs_symlink_inode_operations;
+			break;
+		case S_IFDIR:
+			inode->i_nlink++;
+			if(v9ses->extended)
+				inode->i_op = &v9fs_dir_inode_operations_ext;
+			else
+				inode->i_op = &v9fs_dir_inode_operations;
+			inode->i_fop = &v9fs_dir_operations;
+			break;
+		default:
+			dprintk(DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
+				mode, mode & S_IFMT);
+			return ERR_PTR(-EINVAL);
+		}
+	} else {
+		eprintk(KERN_WARNING, "Problem allocating inode\n");
+		return ERR_PTR(-ENOMEM);
+	}
+	return inode;
+}
+
+/**
+ * v9fs_create - helper function to create files and directories
+ * @dir: directory inode file is being created in
+ * @file_dentry: dentry file is being created in
+ * @perm: permissions file is being created with
+ * @open_mode: resulting open mode for file
+ *
+ */
+
+static int
+v9fs_create(struct inode *dir,
+	    struct dentry *file_dentry,
+	    unsigned int perm, unsigned int open_mode)
+{
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
+	struct super_block *sb = dir->i_sb;
+	struct v9fs_fid *dirfid =
+	    v9fs_fid_lookup(file_dentry->d_parent, FID_WALK);
+	struct v9fs_fid *fid = NULL;
+	struct inode *file_inode = NULL;
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_qid qid;
+	struct stat newstat;
+	int dirfidnum = -1;
+	long newfid = -1;
+	int result = 0;
+	unsigned int iounit = 0;
+
+	perm = unixmode2p9mode(v9ses, perm);
+
+	dprintk(DEBUG_VFS, "dir: %p dentry: %p perm: %o mode: %o\n", dir,
+		file_dentry, perm, open_mode);
+
+	if (!dirfid)
+		return -EBADF;
+
+	dirfidnum = dirfid->fid;
+	if (dirfidnum < 0) {
+		dprintk(DEBUG_ERROR, "No fid for the directory #%lu\n",
+			dir->i_ino);
+		return -EBADF;
+	}
+
+	if (file_dentry->d_inode) {
+		dprintk(DEBUG_ERROR,
+			"Odd. There is an inode for dir %lu, name :%s:\n",
+			dir->i_ino, file_dentry->d_name.name);
+		return -EEXIST;
+	}
+
+	newfid = v9fs_get_idpool(&v9ses->fidpool);
+	if (newfid < 0) {
+		eprintk(KERN_WARNING, "no free fids available\n");
+		return -ENOSPC;
+	}
+
+	result = v9fs_t_walk(v9ses, dirfidnum, newfid, NULL, &fcall);
+	if (result < 0) {
+		dprintk(DEBUG_ERROR, "clone error: %s\n", FCALL_ERROR(fcall));
+		v9fs_put_idpool(newfid, &v9ses->fidpool);
+		newfid = 0;
+		goto CleanUpFid;
+	}
+
+	kfree(fcall);
+
+	result = v9fs_t_create(v9ses, newfid, (char *)file_dentry->d_name.name,
+			       perm, open_mode, &fcall);
+	if (result < 0) {
+		dprintk(DEBUG_ERROR, "create fails: %s(%d)\n",
+			FCALL_ERROR(fcall), result);
+
+		goto CleanUpFid;
+	}
+
+	iounit = fcall->params.rcreate.iounit;
+	qid = fcall->params.rcreate.qid;
+	kfree(fcall);
+
+	fid = v9fs_fid_create(file_dentry);
+	if (!fid) {
+		result = -ENOMEM;
+		goto CleanUpFid;
+	}
+
+	fid->fid = newfid;
+	fid->fidopen = 0;
+	fid->fidcreate = 1;
+	fid->qid = qid;
+	fid->iounit = iounit;
+	fid->rdir_pos = 0;
+	fid->rdir_fcall = NULL;
+	fid->v9ses = v9ses;
+
+	if ((perm & V9FS_DMSYMLINK) || (perm & V9FS_DMLINK) ||
+	    (perm & V9FS_DMNAMEDPIPE) || (perm & V9FS_DMSOCKET) ||
+	    (perm & V9FS_DMDEVICE))
+		return 0;
+
+	result = v9fs_t_stat(v9ses, newfid, &fcall);
+	if (result < 0) {
+		dprintk(DEBUG_ERROR, "stat error: %s(%d)\n", FCALL_ERROR(fcall),
+			result);
+		goto CleanUpFid;
+	}
+
+	v9fs_mistat2unix(fcall->params.rstat.stat, &newstat, sb);
+
+	file_inode = v9fs_get_inode(sb, newstat.st_mode);
+	if ((!file_inode) || IS_ERR(file_inode)) {
+		dprintk(DEBUG_ERROR, "create inode failed\n");
+		result = -EBADF;
+		goto CleanUpFid;
+	}
+
+	v9fs_mistat2inode(fcall->params.rstat.stat, file_inode, sb);
+	kfree(fcall);
+	d_instantiate(file_dentry, file_inode);
+
+	if (perm & V9FS_DMDIR) {
+		if (v9fs_t_clunk(v9ses, newfid, &fcall))
+			dprintk(DEBUG_ERROR, "clunk for mkdir failed: %s\n",
+				FCALL_ERROR(fcall));
+
+		v9fs_put_idpool(newfid, &v9ses->fidpool);
+		kfree(fcall);
+		fid->fidopen = 0;
+		fid->fidcreate = 0;
+		d_drop(file_dentry);
+	}
+
+	return 0;
+
+      CleanUpFid:
+	kfree(fcall);
+
+	if (newfid) {
+		if (v9fs_t_clunk(v9ses, newfid, &fcall))
+			dprintk(DEBUG_ERROR, "clunk failed: %s\n",
+				FCALL_ERROR(fcall));
+
+		v9fs_put_idpool(newfid, &v9ses->fidpool);
+		kfree(fcall);
+	}
+	return result;
+}
+
+/**
+ * v9fs_remove - helper function to remove files and directories
+ * @dir: directory inode that is being deleted
+ * @file:  dentry that is being deleted
+ * @rmdir: removing a directory
+ *
+ */
+
+static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
+{
+	struct v9fs_fcall *fcall = NULL;
+	struct super_block *sb = NULL;
+	struct v9fs_session_info *v9ses = NULL;
+	struct v9fs_fid *v9fid = NULL;
+	struct inode *file_inode = NULL;
+	int fid = -1;
+	int result = 0;
+
+	dprintk(DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
+		rmdir);
+
+	file_inode = file->d_inode;
+	sb = file_inode->i_sb;
+	v9ses = v9fs_inode2v9ses(file_inode);
+	v9fid = v9fs_fid_lookup(file, FID_OP);
+
+	if (!v9fid) {
+		dprintk(DEBUG_ERROR,
+			"no v9fs_fid\n");
+		return -EBADF;
+	}
+
+	fid = v9fid->fid;
+	if (fid < 0) {
+		dprintk(DEBUG_ERROR, "inode #%lu, no fid!\n",
+			file_inode->i_ino);
+		return -EBADF;
+	}
+
+	result = v9fs_t_remove(v9ses, fid, &fcall);
+	if (result < 0)
+		dprintk(DEBUG_ERROR, "remove of file fails: %s(%d)\n",
+			FCALL_ERROR(fcall), result);
+	else {
+		v9fs_put_idpool(fid, &v9ses->fidpool);
+		v9fs_fid_destroy(v9fid);
+	}
+
+	kfree(fcall);
+	return result;
+}
+
+/**
+ * v9fs_vfs_create - VFS hook to create files
+ * @inode: directory inode that is being deleted
+ * @dentry:  dentry that is being deleted
+ * @perm: create permissions
+ * @nd: path information
+ *
+ */
+
+static int
+v9fs_vfs_create(struct inode *inode, struct dentry *dentry, int perm,
+		struct nameidata *nd)
+{
+	return v9fs_create(inode, dentry, perm, O_RDWR);
+}
+
+/**
+ * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
+ * @inode:  inode that is being unlinked
+ * @dentry: dentry that is being unlinked
+ * @mode: mode for new directory
+ *
+ */
+
+static int v9fs_vfs_mkdir(struct inode *inode, struct dentry *dentry, int mode)
+{
+	return v9fs_create(inode, dentry, mode | S_IFDIR, O_RDONLY);
+}
+
+/**
+ * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
+ * @dir:  inode that is being walked from
+ * @dentry: dentry that is being walked to?
+ * @nameidata: path data
+ *
+ */
+
+static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
+				      struct nameidata *nameidata)
+{
+	struct super_block *sb;
+	struct v9fs_session_info *v9ses;
+	struct v9fs_fid *dirfid;
+	struct v9fs_fid *fid;
+	struct inode *inode;
+	struct v9fs_fcall *fcall = NULL;
+	struct stat newstat;
+	int dirfidnum = -1;
+	int newfid = -1;
+	int result = 0;
+
+	dprintk(DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
+		dir, dentry->d_iname, dentry, nameidata);
+
+	sb = dir->i_sb;
+	v9ses = v9fs_inode2v9ses(dir);
+	dirfid = v9fs_fid_lookup(dentry->d_parent, FID_WALK);
+
+	if (!dirfid) {
+		dprintk(DEBUG_ERROR, "no dirfid\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	dirfidnum = dirfid->fid;
+
+	if (dirfidnum < 0) {
+		dprintk(DEBUG_ERROR, "no dirfid for inode %p, #%lu\n",
+			dir, dir->i_ino);
+		return ERR_PTR(-EBADF);
+	}
+
+	newfid = v9fs_get_idpool(&v9ses->fidpool);
+	if (newfid < 0) {
+		eprintk(KERN_WARNING, "newfid fails!\n");
+		return ERR_PTR(-ENOSPC);
+	}
+
+	result =
+	    v9fs_t_walk(v9ses, dirfidnum, newfid, (char *)dentry->d_name.name,
+			NULL);
+	if (result < 0) {
+		v9fs_put_idpool(newfid, &v9ses->fidpool);
+		if (result == -ENOENT) {
+			d_add(dentry, NULL);
+			dprintk(DEBUG_ERROR,
+				"Return negative dentry %p count %d\n",
+				dentry, atomic_read(&dentry->d_count));
+			return NULL;
+		}
+		dprintk(DEBUG_ERROR, "walk error:%d\n", result);
+		goto FreeFcall;
+	}
+
+	result = v9fs_t_stat(v9ses, newfid, &fcall);
+	if (result < 0) {
+		dprintk(DEBUG_ERROR, "stat error\n");
+		goto FreeFcall;
+	}
+
+	v9fs_mistat2unix(fcall->params.rstat.stat, &newstat, sb);
+	inode = v9fs_get_inode(sb, newstat.st_mode);
+
+	if (IS_ERR(inode) && (PTR_ERR(inode) == -ENOSPC)) {
+		eprintk(KERN_WARNING, "inode alloc failes, returns %ld\n",
+			PTR_ERR(inode));
+
+		result = -ENOSPC;
+		goto FreeFcall;
+	}
+
+	inode->i_ino = v9fs_qid2ino(&fcall->params.rstat.stat->qid);
+
+	fid = v9fs_fid_create(dentry);
+	if (fid == NULL) {
+		dprintk(DEBUG_ERROR, "couldn't insert\n");
+		result = -ENOMEM;
+		goto FreeFcall;
+	}
+
+	fid->fid = newfid;
+	fid->fidopen = 0;
+	fid->v9ses = v9ses;
+	fid->qid = fcall->params.rstat.stat->qid;
+
+	dentry->d_op = &v9fs_dentry_operations;
+	v9fs_mistat2inode(fcall->params.rstat.stat, inode, inode->i_sb);
+
+	d_add(dentry, inode);
+	kfree(fcall);
+
+	return NULL;
+
+      FreeFcall:
+	kfree(fcall);
+	return ERR_PTR(result);
+}
+
+/**
+ * v9fs_vfs_unlink - VFS unlink hook to delete an inode
+ * @i:  inode that is being unlinked
+ * @d: dentry that is being unlinked
+ *
+ */
+
+static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
+{
+	return v9fs_remove(i, d, 0);
+}
+
+/**
+ * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
+ * @i:  inode that is being unlinked
+ * @d: dentry that is being unlinked
+ *
+ */
+
+static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
+{
+	return v9fs_remove(i, d, 1);
+}
+
+/**
+ * v9fs_vfs_rename - VFS hook to rename an inode
+ * @old_dir:  old dir inode
+ * @old_dentry: old dentry
+ * @new_dir: new dir inode
+ * @new_dentry: new dentry
+ *
+ */
+
+static int
+v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+		struct inode *new_dir, struct dentry *new_dentry)
+{
+	struct inode *old_inode = old_dentry->d_inode;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(old_inode);
+	struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry, FID_WALK);
+	struct v9fs_fid *olddirfid =
+	    v9fs_fid_lookup(old_dentry->d_parent, FID_WALK);
+	struct v9fs_fid *newdirfid =
+	    v9fs_fid_lookup(new_dentry->d_parent, FID_WALK);
+	struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
+	struct v9fs_fcall *fcall = NULL;
+	int fid = -1;
+	int olddirfidnum = -1;
+	int newdirfidnum = -1;
+	int retval = 0;
+
+	dprintk(DEBUG_VFS, "\n");
+
+	if (!mistat)
+		return -ENOMEM;
+
+	if ((!oldfid) || (!olddirfid) || (!newdirfid)) {
+		dprintk(DEBUG_ERROR, "problem with arguments\n");
+		return -EBADF;
+	}
+
+	/* 9P can only handle file rename in the same directory */
+	if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
+		dprintk(DEBUG_ERROR, "old dir and new dir are different\n");
+		retval = -EPERM;
+		goto FreeFcallnBail;
+	}
+
+	fid = oldfid->fid;
+	olddirfidnum = olddirfid->fid;
+	newdirfidnum = newdirfid->fid;
+
+	if (fid < 0) {
+		dprintk(DEBUG_ERROR, "no fid for old file #%lu\n",
+			old_inode->i_ino);
+		retval = -EBADF;
+		goto FreeFcallnBail;
+	}
+
+	v9fs_blank_mistat(v9ses, mistat);
+
+	strcpy(mistat->data + 1, v9ses->name);
+	mistat->name = mistat->data + 1 + strlen(v9ses->name);
+
+	if (new_dentry->d_name.len >
+	    (v9ses->maxdata - strlen(v9ses->name) - sizeof(struct v9fs_stat))) {
+		dprintk(DEBUG_ERROR, "new name too long\n");
+		goto FreeFcallnBail;
+	}
+
+	strcpy(mistat->name, new_dentry->d_name.name);
+	retval = v9fs_t_wstat(v9ses, fid, mistat, &fcall);
+
+      FreeFcallnBail:
+	kfree(mistat);
+
+	if (retval < 0)
+		dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
+			FCALL_ERROR(fcall));
+
+	kfree(fcall);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_getattr - retreive file metadata
+ * @mnt - mount information
+ * @dentry - file to get attributes on
+ * @stat - metadata structure to populate
+ *
+ */
+
+static int
+v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
+		 struct kstat *stat)
+{
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	struct v9fs_fid *fid = v9fs_fid_lookup(dentry, FID_OP);
+	int err = -EPERM;
+
+	dprintk(DEBUG_VFS, "dentry: %p\n", dentry);
+	if (!fid) {
+		dprintk(DEBUG_ERROR,
+			"couldn't find fid associated with dentry\n");
+		return -EBADF;
+	}
+
+	err = v9fs_t_stat(v9ses, fid->fid, &fcall);
+
+	if (err < 0)
+		dprintk(DEBUG_ERROR, "stat error\n");
+	else {
+		v9fs_mistat2inode(fcall->params.rstat.stat, dentry->d_inode,
+				  dentry->d_inode->i_sb);
+		generic_fillattr(dentry->d_inode, stat);
+	}
+
+	kfree(fcall);
+	return err;
+}
+
+/**
+ * v9fs_vfs_setattr - set file metadata
+ * @dentry: file whose metadata to set
+ * @iattr: metadata assignment structure
+ *
+ */
+
+static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
+{
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	struct v9fs_fid *fid = v9fs_fid_lookup(dentry, FID_OP);
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
+	int res = -EPERM;
+
+	dprintk(DEBUG_VFS, "\n");
+
+	if (!mistat)
+		return -ENOMEM;
+
+	if (!fid) {
+		dprintk(DEBUG_ERROR,
+			"Couldn't find fid associated with dentry\n");
+		return -EBADF;
+	}
+
+	v9fs_blank_mistat(v9ses, mistat);
+	if (iattr->ia_valid & ATTR_MODE)
+		mistat->mode = unixmode2p9mode(v9ses, iattr->ia_mode);
+
+	if (iattr->ia_valid & ATTR_MTIME)
+		mistat->mtime = iattr->ia_mtime.tv_sec;
+
+	if (iattr->ia_valid & ATTR_ATIME)
+		mistat->atime = iattr->ia_atime.tv_sec;
+
+	if (iattr->ia_valid & ATTR_SIZE)
+		mistat->length = iattr->ia_size;
+
+	if (v9ses->extended) {
+		char *ptr = mistat->data+1;
+
+		if (iattr->ia_valid & ATTR_UID) {
+			mistat->uid = ptr;
+			ptr += 1+sprintf(ptr, "%08x", iattr->ia_uid);
+			mistat->n_uid = iattr->ia_uid;
+		}
+
+		if (iattr->ia_valid & ATTR_GID) {
+			mistat->gid = ptr;
+			ptr += 1+sprintf(ptr, "%08x", iattr->ia_gid);
+			mistat->n_gid = iattr->ia_gid;
+		}
+	}
+
+	res = v9fs_t_wstat(v9ses, fid->fid, mistat, &fcall);
+
+	if (res < 0)
+		dprintk(DEBUG_ERROR, "wstat error: %s\n", FCALL_ERROR(fcall));
+
+	kfree(mistat);
+	kfree(fcall);
+
+	if (res >= 0)
+		res = inode_setattr(dentry->d_inode, iattr);
+
+	return res;
+}
+
+/**
+ * v9fs_mistat2inode - populate an inode structure with mistat info
+ * @mistat: Plan 9 metadata (mistat) structure
+ * @inode: inode to populate
+ * @sb: superblock of filesystem
+ *
+ */
+
+void
+v9fs_mistat2inode(struct v9fs_stat *mistat, struct inode *inode,
+		  struct super_block *sb)
+{
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+	inode->i_nlink = 1;
+
+	inode->i_atime.tv_sec = mistat->atime;
+	inode->i_mtime.tv_sec = mistat->mtime;
+	inode->i_ctime.tv_sec = mistat->mtime;
+
+	inode->i_uid = -1;
+	inode->i_gid = -1;
+
+	if (v9ses->extended) {
+		/* TODO: string to uid mapping via user-space daemon */
+		inode->i_uid = mistat->n_uid;
+		inode->i_gid = mistat->n_gid;
+
+		if (mistat->n_uid == -1)
+			sscanf(mistat->uid, "%x", &inode->i_uid);
+
+		if (mistat->n_gid == -1)
+			sscanf(mistat->gid, "%x", &inode->i_gid);
+	}
+
+	if (inode->i_uid == -1)
+		inode->i_uid = v9ses->uid;
+	if (inode->i_gid == -1)
+		inode->i_gid = v9ses->gid;
+
+	inode->i_mode = p9mode2unixmode(v9ses, mistat->mode);
+	if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
+		char type = 0;
+		int major = -1;
+		int minor = -1;
+		sscanf(mistat->extension, "%c %u %u", &type, &major, &minor);
+		switch (type) {
+		case 'c':
+			inode->i_mode &= ~S_IFBLK;
+			inode->i_mode |= S_IFCHR;
+			break;
+		case 'b':
+			break;
+		default:
+			dprintk(DEBUG_ERROR, "Unknown special type %c (%s)\n",
+				type, mistat->extension);
+		};
+		inode->i_rdev = MKDEV(major, minor);
+	} else
+		inode->i_rdev = 0;
+
+	inode->i_size = mistat->length;
+
+	inode->i_blksize = sb->s_blocksize;
+	inode->i_blocks =
+	    (inode->i_size + inode->i_blksize - 1) >> sb->s_blocksize_bits;
+}
+
+/**
+ * v9fs_qid2ino - convert qid into inode number
+ * @qid: qid to hash
+ *
+ * BUG: potential for inode number collisions?
+ */
+
+ino_t v9fs_qid2ino(struct v9fs_qid *qid)
+{
+	u64 path = qid->path + 2;
+	ino_t i = 0;
+
+	if (sizeof(ino_t) == sizeof(path))
+		memcpy(&i, &path, sizeof(ino_t));
+	else
+		i = (ino_t) (path ^ (path >> 32));
+
+	return i;
+}
+
+/**
+ * v9fs_vfs_symlink - helper function to create symlinks
+ * @dir: directory inode containing symlink
+ * @dentry: dentry for symlink
+ * @symname: symlink data
+ *
+ * See 9P2000.u RFC for more information
+ *
+ */
+
+static int
+v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+{
+	int retval = -EPERM;
+	struct v9fs_fid *newfid;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
+
+	dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
+		symname);
+
+	if (!mistat)
+		return -ENOMEM;
+
+	if (!v9ses->extended) {
+		dprintk(DEBUG_ERROR, "not extended\n");
+		goto FreeFcall;
+	}
+
+	/* issue a create */
+	retval = v9fs_create(dir, dentry, S_IFLNK, 0);
+	if (retval != 0)
+		goto FreeFcall;
+
+	newfid = v9fs_fid_lookup(dentry, FID_OP);
+
+	/* issue a twstat */
+	v9fs_blank_mistat(v9ses, mistat);
+	strcpy(mistat->data + 1, symname);
+	mistat->extension = mistat->data + 1;
+	retval = v9fs_t_wstat(v9ses, newfid->fid, mistat, &fcall);
+	if (retval < 0) {
+		dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
+			FCALL_ERROR(fcall));
+		goto FreeFcall;
+	}
+
+	kfree(fcall);
+
+	if (v9fs_t_clunk(v9ses, newfid->fid, &fcall)) {
+		dprintk(DEBUG_ERROR, "clunk for symlink failed: %s\n",
+			FCALL_ERROR(fcall));
+		goto FreeFcall;
+	}
+
+	d_drop(dentry);		/* FID - will this also clunk? */
+
+      FreeFcall:
+	kfree(mistat);
+	kfree(fcall);
+
+	return retval;
+}
+
+/**
+ * v9fs_readlink - read a symlink's location (internal version)
+ * @dentry: dentry for symlink
+ * @buffer: buffer to load symlink location into
+ * @buflen: length of buffer
+ *
+ */
+
+static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
+{
+	int retval = -EPERM;
+
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	struct v9fs_fid *fid = v9fs_fid_lookup(dentry, FID_OP);
+
+	if (!fid) {
+		dprintk(DEBUG_ERROR, "could not resolve fid from dentry\n");
+		retval = -EBADF;
+		goto FreeFcall;
+	}
+
+	if (!v9ses->extended) {
+		retval = -EBADF;
+		dprintk(DEBUG_ERROR, "not extended\n");
+		goto FreeFcall;
+	}
+
+	dprintk(DEBUG_VFS, " %s\n", dentry->d_name.name);
+	retval = v9fs_t_stat(v9ses, fid->fid, &fcall);
+
+	if (retval < 0) {
+		dprintk(DEBUG_ERROR, "stat error\n");
+		goto FreeFcall;
+	}
+
+	if (!fcall)
+		return -EIO;
+
+	if (!(fcall->params.rstat.stat->mode & V9FS_DMSYMLINK)) {
+		retval = -EINVAL;
+		goto FreeFcall;
+	}
+
+	/* copy extension buffer into buffer */
+	if (strlen(fcall->params.rstat.stat->extension) < buflen)
+		buflen = strlen(fcall->params.rstat.stat->extension);
+
+	memcpy(buffer, fcall->params.rstat.stat->extension, buflen + 1);
+
+	retval = buflen;
+
+      FreeFcall:
+	kfree(fcall);
+
+	return retval;
+}
+
+/**
+ * v9fs_vfs_readlink - read a symlink's location
+ * @dentry: dentry for symlink
+ * @buf: buffer to load symlink location into
+ * @buflen: length of buffer
+ *
+ */
+
+static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
+			     int buflen)
+{
+	int retval;
+	int ret;
+	char *link = __getname();
+
+	if (strlen(link) < buflen)
+		buflen = strlen(link);
+
+	dprintk(DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);
+
+	retval = v9fs_readlink(dentry, link, buflen);
+
+	if (retval > 0) {
+		if ((ret = copy_to_user(buffer, link, retval)) != 0) {
+			dprintk(DEBUG_ERROR, "problem copying to user: %d\n",
+				ret);
+			retval = ret;
+		}
+	}
+
+	putname(link);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_follow_link - follow a symlink path
+ * @dentry: dentry for symlink
+ * @nd: nameidata
+ *
+ */
+
+static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	int len = 0;
+	char *link = __getname();
+
+	dprintk(DEBUG_VFS, "%s n", dentry->d_name.name);
+
+	if (!link)
+		link = ERR_PTR(-ENOMEM);
+	else {
+		len = v9fs_readlink(dentry, link, strlen(link));
+
+		if (len < 0) {
+			putname(link);
+			link = ERR_PTR(len);
+		} else
+			link[len] = 0;
+	}
+	nd_set_link(nd, link);
+
+	return NULL;
+}
+
+/**
+ * v9fs_vfs_put_link - release a symlink path
+ * @dentry: dentry for symlink
+ * @nd: nameidata
+ *
+ */
+
+static void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
+{
+	char *s = nd_get_link(nd);
+
+	dprintk(DEBUG_VFS, " %s %s\n", dentry->d_name.name, s);
+	if (!IS_ERR(s))
+		putname(s);
+}
+
+/**
+ * v9fs_vfs_link - create a hardlink
+ * @old_dentry: dentry for file to link to
+ * @dir: inode destination for new link
+ * @dentry: dentry for link
+ *
+ */
+
+/* XXX - lots of code dup'd from symlink and creates,
+ * figure out a better reuse strategy
+ */
+
+static int
+v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
+	      struct dentry *dentry)
+{
+	int retval = -EPERM;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
+	struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry, FID_OP);
+	struct v9fs_fid *newfid = NULL;
+	char *symname = __getname();
+
+	dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
+		old_dentry->d_name.name);
+
+	if (!v9ses->extended) {
+		dprintk(DEBUG_ERROR, "not extended\n");
+		goto FreeMem;
+	}
+
+	/* get fid of old_dentry */
+	sprintf(symname, "hardlink(%d)\n", oldfid->fid);
+
+	/* issue a create */
+	retval = v9fs_create(dir, dentry, V9FS_DMLINK, 0);
+	if (retval != 0)
+		goto FreeMem;
+
+	newfid = v9fs_fid_lookup(dentry, FID_OP);
+	if (!newfid) {
+		dprintk(DEBUG_ERROR, "couldn't resolve fid from dentry\n");
+		goto FreeMem;
+	}
+
+	/* issue a twstat */
+	v9fs_blank_mistat(v9ses, mistat);
+	strcpy(mistat->data + 1, symname);
+	mistat->extension = mistat->data + 1;
+	retval = v9fs_t_wstat(v9ses, newfid->fid, mistat, &fcall);
+	if (retval < 0) {
+		dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
+			FCALL_ERROR(fcall));
+		goto FreeMem;
+	}
+
+	kfree(fcall);
+
+	if (v9fs_t_clunk(v9ses, newfid->fid, &fcall)) {
+		dprintk(DEBUG_ERROR, "clunk for symlink failed: %s\n",
+			FCALL_ERROR(fcall));
+		goto FreeMem;
+	}
+
+	d_drop(dentry);		/* FID - will this also clunk? */
+
+	kfree(fcall);
+	fcall = NULL;
+
+      FreeMem:
+	kfree(mistat);
+	kfree(fcall);
+	putname(symname);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_mknod - create a special file
+ * @dir: inode destination for new link
+ * @dentry: dentry for file
+ * @mode: mode for creation
+ * @dev_t: device associated with special file
+ *
+ */
+
+static int
+v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
+{
+	int retval = -EPERM;
+	struct v9fs_fid *newfid;
+	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
+	struct v9fs_fcall *fcall = NULL;
+	struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
+	char *symname = __getname();
+
+	dprintk(DEBUG_VFS, " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
+		dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
+
+	if (!mistat)
+		return -ENOMEM;
+
+	if (!new_valid_dev(rdev)) {
+		retval = -EINVAL;
+		goto FreeMem;
+	}
+
+	if (!v9ses->extended) {
+		dprintk(DEBUG_ERROR, "not extended\n");
+		goto FreeMem;
+	}
+
+	/* issue a create */
+	retval = v9fs_create(dir, dentry, mode, 0);
+
+	if (retval != 0)
+		goto FreeMem;
+
+	newfid = v9fs_fid_lookup(dentry, FID_OP);
+	if (!newfid) {
+		dprintk(DEBUG_ERROR, "coudn't resove fid from dentry\n");
+		retval = -EINVAL;
+		goto FreeMem;
+	}
+
+	/* build extension */
+	if (S_ISBLK(mode))
+		sprintf(symname, "b %u %u", MAJOR(rdev), MINOR(rdev));
+	else if (S_ISCHR(mode))
+		sprintf(symname, "c %u %u", MAJOR(rdev), MINOR(rdev));
+	else if (S_ISFIFO(mode))
+		;	/* DO NOTHING */
+	else {
+		retval = -EINVAL;
+		goto FreeMem;
+	}
+
+	if (!S_ISFIFO(mode)) {
+		/* issue a twstat */
+		v9fs_blank_mistat(v9ses, mistat);
+		strcpy(mistat->data + 1, symname);
+		mistat->extension = mistat->data + 1;
+		retval = v9fs_t_wstat(v9ses, newfid->fid, mistat, &fcall);
+		if (retval < 0) {
+			dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
+				FCALL_ERROR(fcall));
+			goto FreeMem;
+		}
+	}
+
+	/* need to update dcache so we show up */
+	kfree(fcall);
+
+	if (v9fs_t_clunk(v9ses, newfid->fid, &fcall)) {
+		dprintk(DEBUG_ERROR, "clunk for symlink failed: %s\n",
+			FCALL_ERROR(fcall));
+		goto FreeMem;
+	}
+
+	d_drop(dentry);		/* FID - will this also clunk? */
+
+      FreeMem:
+	kfree(mistat);
+	kfree(fcall);
+	putname(symname);
+
+	return retval;
+}
+
+static struct inode_operations v9fs_dir_inode_operations_ext = {
+	.create = v9fs_vfs_create,
+	.lookup = v9fs_vfs_lookup,
+	.symlink = v9fs_vfs_symlink,
+	.link = v9fs_vfs_link,
+	.unlink = v9fs_vfs_unlink,
+	.mkdir = v9fs_vfs_mkdir,
+	.rmdir = v9fs_vfs_rmdir,
+	.mknod = v9fs_vfs_mknod,
+	.rename = v9fs_vfs_rename,
+	.readlink = v9fs_vfs_readlink,
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
+
+static struct inode_operations v9fs_dir_inode_operations = {
+	.create = v9fs_vfs_create,
+	.lookup = v9fs_vfs_lookup,
+	.unlink = v9fs_vfs_unlink,
+	.mkdir = v9fs_vfs_mkdir,
+	.rmdir = v9fs_vfs_rmdir,
+	.mknod = v9fs_vfs_mknod,
+	.rename = v9fs_vfs_rename,
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
+
+static struct inode_operations v9fs_file_inode_operations = {
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
+
+static struct inode_operations v9fs_symlink_inode_operations = {
+	.readlink = v9fs_vfs_readlink,
+	.follow_link = v9fs_vfs_follow_link,
+	.put_link = v9fs_vfs_put_link,
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
new file mode 100644
index 00000000000..868f350b2c5
--- /dev/null
+++ b/fs/9p/vfs_super.c
@@ -0,0 +1,280 @@
+/*
+ *  linux/fs/9p/vfs_super.c
+ *
+ * This file contians superblock ops for 9P2000. It is intended that
+ * you mount this file system on directories.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "conv.h"
+#include "fid.h"
+
+static void v9fs_clear_inode(struct inode *);
+static struct super_operations v9fs_super_ops;
+
+/**
+ * v9fs_clear_inode - release an inode
+ * @inode: inode to release
+ *
+ */
+
+static void v9fs_clear_inode(struct inode *inode)
+{
+	filemap_fdatawrite(inode->i_mapping);
+}
+
+/**
+ * v9fs_set_super - set the superblock
+ * @s: super block
+ * @data: file system specific data
+ *
+ */
+
+static int v9fs_set_super(struct super_block *s, void *data)
+{
+	s->s_fs_info = data;
+	return set_anon_super(s, data);
+}
+
+/**
+ * v9fs_fill_super - populate superblock with info
+ * @sb: superblock
+ * @v9ses: session information
+ *
+ */
+
+static void
+v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
+		int flags)
+{
+	sb->s_maxbytes = MAX_LFS_FILESIZE;
+	sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
+	sb->s_blocksize = 1 << sb->s_blocksize_bits;
+	sb->s_magic = V9FS_MAGIC;
+	sb->s_op = &v9fs_super_ops;
+
+	sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC |
+	    MS_NODIRATIME | MS_NOATIME;
+}
+
+/**
+ * v9fs_get_sb - mount a superblock
+ * @fs_type: file system type
+ * @flags: mount flags
+ * @dev_name: device name that was mounted
+ * @data: mount options
+ *
+ */
+
+static struct super_block *v9fs_get_sb(struct file_system_type
+				       *fs_type, int flags,
+				       const char *dev_name, void *data)
+{
+	struct super_block *sb = NULL;
+	struct v9fs_fcall *fcall = NULL;
+	struct inode *inode = NULL;
+	struct dentry *root = NULL;
+	struct v9fs_session_info *v9ses = NULL;
+	struct v9fs_fid *root_fid = NULL;
+	int mode = S_IRWXUGO | S_ISVTX;
+	uid_t uid = current->fsuid;
+	gid_t gid = current->fsgid;
+	int stat_result = 0;
+	int newfid = 0;
+	int retval = 0;
+
+	dprintk(DEBUG_VFS, " \n");
+
+	v9ses = kcalloc(1, sizeof(struct v9fs_session_info), GFP_KERNEL);
+	if (!v9ses)
+		return ERR_PTR(-ENOMEM);
+
+	if ((newfid = v9fs_session_init(v9ses, dev_name, data)) < 0) {
+		dprintk(DEBUG_ERROR, "problem initiating session\n");
+		retval = newfid;
+		goto free_session;
+	}
+
+	sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
+
+	v9fs_fill_super(sb, v9ses, flags);
+
+	inode = v9fs_get_inode(sb, S_IFDIR | mode);
+	if (IS_ERR(inode)) {
+		retval = PTR_ERR(inode);
+		goto put_back_sb;
+	}
+
+	inode->i_uid = uid;
+	inode->i_gid = gid;
+
+	root = d_alloc_root(inode);
+
+	if (!root) {
+		retval = -ENOMEM;
+		goto release_inode;
+	}
+
+	sb->s_root = root;
+
+	/* Setup the Root Inode */
+	root_fid = v9fs_fid_create(root);
+	if (root_fid == NULL) {
+		retval = -ENOMEM;
+		goto release_dentry;
+	}
+
+	root_fid->fidopen = 0;
+	root_fid->v9ses = v9ses;
+
+	stat_result = v9fs_t_stat(v9ses, newfid, &fcall);
+	if (stat_result < 0) {
+		dprintk(DEBUG_ERROR, "stat error\n");
+		v9fs_t_clunk(v9ses, newfid, NULL);
+		v9fs_put_idpool(newfid, &v9ses->fidpool);
+	} else {
+		root_fid->fid = newfid;
+		root_fid->qid = fcall->params.rstat.stat->qid;
+		root->d_inode->i_ino =
+		    v9fs_qid2ino(&fcall->params.rstat.stat->qid);
+		v9fs_mistat2inode(fcall->params.rstat.stat, root->d_inode, sb);
+	}
+
+	kfree(fcall);
+
+	if (stat_result < 0) {
+		retval = stat_result;
+		goto release_dentry;
+	}
+
+	return sb;
+
+      release_dentry:
+	dput(sb->s_root);
+
+      release_inode:
+	iput(inode);
+
+      put_back_sb:
+	up_write(&sb->s_umount);
+	deactivate_super(sb);
+	v9fs_session_close(v9ses);
+
+      free_session:
+	kfree(v9ses);
+
+	return ERR_PTR(retval);
+}
+
+/**
+ * v9fs_kill_super - Kill Superblock
+ * @s: superblock
+ *
+ */
+
+static void v9fs_kill_super(struct super_block *s)
+{
+	struct v9fs_session_info *v9ses = s->s_fs_info;
+
+	dprintk(DEBUG_VFS, " %p\n", s);
+
+	v9fs_dentry_release(s->s_root);	/* clunk root */
+
+	kill_anon_super(s);
+
+	v9fs_session_close(v9ses);
+	kfree(v9ses);
+	dprintk(DEBUG_VFS, "exiting kill_super\n");
+}
+
+/**
+ * v9fs_show_options - Show mount options in /proc/mounts
+ * @m: seq_file to write to
+ * @mnt: mount descriptor
+ *
+ */
+
+static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+	struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;
+
+	if (v9ses->debug != 0)
+		seq_printf(m, ",debug=%u", v9ses->debug);
+	if (v9ses->port != V9FS_PORT)
+		seq_printf(m, ",port=%u", v9ses->port);
+	if (v9ses->maxdata != 9000)
+		seq_printf(m, ",msize=%u", v9ses->maxdata);
+	if (v9ses->afid != ~0)
+		seq_printf(m, ",afid=%u", v9ses->afid);
+	if (v9ses->proto == PROTO_UNIX)
+		seq_puts(m, ",proto=unix");
+	if (v9ses->extended == 0)
+		seq_puts(m, ",noextend");
+	if (v9ses->nodev == 1)
+		seq_puts(m, ",nodevmap");
+	seq_printf(m, ",name=%s", v9ses->name);
+	seq_printf(m, ",aname=%s", v9ses->remotename);
+	seq_printf(m, ",uid=%u", v9ses->uid);
+	seq_printf(m, ",gid=%u", v9ses->gid);
+	return 0;
+}
+
+static void
+v9fs_umount_begin(struct super_block *sb)
+{
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+	v9fs_session_cancel(v9ses);
+}
+
+static struct super_operations v9fs_super_ops = {
+	.statfs = simple_statfs,
+	.clear_inode = v9fs_clear_inode,
+	.show_options = v9fs_show_options,
+	.umount_begin = v9fs_umount_begin,
+};
+
+struct file_system_type v9fs_fs_type = {
+	.name = "9P",
+	.get_sb = v9fs_get_sb,
+	.kill_sb = v9fs_kill_super,
+	.owner = THIS_MODULE,
+};