[PATCH] v9fs: 9P protocol implementation

This part of the patch contains the 9P protocol functions.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/9p/9p.c b/fs/9p/9p.c
new file mode 100644
index 0000000..e847f50
--- /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;
+}