[PATCH] v9fs: transport modules

This part of the patch contains transport routines.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/9p/mux.h

+/*
+ * 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;
+
+	/* 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);

fs/9p/trans_fd.c

+/*
+ * 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,
+};
+

fs/9p/trans_sock.c

+/*
+ * 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 = trans ? trans->priv : NULL;
+
+	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");
+	}
+
+	kfree(ts);
+}
+
+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,
+};

fs/9p/transport.h

+/*
+ * 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;

fs/9p/v9fs.c

@@ -296,11 +296,6 @@ v9fs_session_init(struct v9fs_session_info *v9ses,
 	case PROTO_FD:
 		trans_proto = &v9fs_trans_fd;
 		*v9ses->remotename = 0;
-		if((v9ses->wfdno == ~0) || (v9ses->rfdno == ~0)) {
-			printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n");
-			retval = -ENOPROTOOPT;
-			goto SessCleanUp;
-		}
 		break;
 	default:
 		printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);