9p: consolidate transport structure

Right now there is a transport module structure which provides per-transport
type functions and data and a transport structure which contains per-instance
public data as well as function pointers to instance specific functions.

This patch moves public transport visible instance data to the client
structure (which in some cases had duplicate data) and consolidates the
functions into the transport module structure.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

fs/9p/v9fs.c

@@ -30,8 +30,8 @@
 #include <linux/parser.h>
 #include <linux/idr.h>
 #include <net/9p/9p.h>
-#include <net/9p/transport.h>
 #include <net/9p/client.h>
+#include <net/9p/transport.h>
 #include "v9fs.h"
 #include "v9fs_vfs.h"
 

include/net/9p/client.h

@@ -26,6 +26,22 @@
 #ifndef NET_9P_CLIENT_H
 #define NET_9P_CLIENT_H
 
+/**
+ * enum p9_trans_status - different states of underlying transports
+ * @Connected: transport is connected and healthy
+ * @Disconnected: transport has been disconnected
+ * @Hung: transport is connected by wedged
+ *
+ * This enumeration details the various states a transport
+ * instatiation can be in.
+ */
+
+enum p9_trans_status {
+	Connected,
+	Disconnected,
+	Hung,
+};
+
 /**
  * struct p9_client - per client instance state
  * @lock: protect @fidlist
@@ -48,7 +64,8 @@ struct p9_client {
 	int msize;
 	unsigned char dotu;
 	struct p9_trans_module *trans_mod;
-	struct p9_trans *trans;
+	enum p9_trans_status status;
+	void *trans;
 	struct p9_conn *conn;
 
 	struct p9_idpool *fidpool;

include/net/9p/transport.h

@@ -26,52 +26,6 @@
 #ifndef NET_9P_TRANSPORT_H
 #define NET_9P_TRANSPORT_H
 
-#include <linux/module.h>
-
-/**
- * enum p9_trans_status - different states of underlying transports
- * @Connected: transport is connected and healthy
- * @Disconnected: transport has been disconnected
- * @Hung: transport is connected by wedged
- *
- * This enumeration details the various states a transport
- * instatiation can be in.
- */
-
-enum p9_trans_status {
-	Connected,
-	Disconnected,
-	Hung,
-};
-
-/**
- * struct p9_trans - per-transport state and API
- * @status: transport &p9_trans_status
- * @msize: negotiated maximum packet size (duplicate from client)
- * @extended: negotiated protocol extensions (duplicate from client)
- * @priv: transport private data
- * @close: member function to disconnect and close the transport
- * @rpc: member function to issue a request to the transport
- *
- * This is the basic API for a transport instance.  It is used as
- * a handle by the client to issue requests.  This interface is currently
- * in flux during reorganization.
- *
- * Bugs: there is lots of duplicated data here and its not clear that
- * the member functions need to be per-instance versus per transport
- * module.
- */
-
-struct p9_trans {
-	enum p9_trans_status status;
-	int msize;
-	unsigned char extended;
-	void *priv;
-	void (*close) (struct p9_trans *);
-	int (*rpc) (struct p9_trans *t, struct p9_fcall *tc,
-							struct p9_fcall **rc);
-};
-
 /**
  * struct p9_trans_module - transport module interface
  * @list: used to maintain a list of currently available transports
@@ -79,12 +33,14 @@ struct p9_trans {
  * @maxsize: transport provided maximum packet size
  * @def: set if this transport should be considered the default
  * @create: member function to create a new connection on this transport
+ * @close: member function to disconnect and close the transport
+ * @rpc: member function to issue a request to the transport
  *
  * This is the basic API for a transport module which is registered by the
  * transport module with the 9P core network module and used by the client
  * to instantiate a new connection on a transport.
  *
- * Bugs: the transport module list isn't protected.
+ * BUGS: the transport module list isn't protected.
  */
 
 struct p9_trans_module {
@@ -92,8 +48,11 @@ struct p9_trans_module {
 	char *name;		/* name of transport */
 	int maxsize;		/* max message size of transport */
 	int def;		/* this transport should be default */
-	struct p9_trans * (*create)(const char *, char *, int, unsigned char);
 	struct module *owner;
+	int (*create)(struct p9_client *, const char *, char *);
+	void (*close) (struct p9_client *);
+	int (*rpc) (struct p9_client *t, struct p9_fcall *tc,
+							struct p9_fcall **rc);
 };
 
 void v9fs_register_trans(struct p9_trans_module *m);

net/9p/client.c

@@ -33,8 +33,8 @@
 #include <linux/uaccess.h>
 #include <net/9p/9p.h>
 #include <linux/parser.h>
-#include <net/9p/transport.h>
 #include <net/9p/client.h>
+#include <net/9p/transport.h>
 
 static struct p9_fid *p9_fid_create(struct p9_client *clnt);
 static void p9_fid_destroy(struct p9_fid *fid);
@@ -136,7 +136,7 @@ int
 p9_client_rpc(struct p9_client *c, struct p9_fcall *tc,
 	struct p9_fcall **rc)
 {
-	return c->trans->rpc(c->trans, tc, rc);
+	return c->trans_mod->rpc(c, tc, rc);
 }
 
 struct p9_client *p9_client_create(const char *dev_name, char *options)
@@ -179,13 +179,9 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
 		clnt, clnt->trans_mod, clnt->msize, clnt->dotu);
 
 
-	clnt->trans = clnt->trans_mod->create(dev_name, options, clnt->msize,
-								clnt->dotu);
-	if (IS_ERR(clnt->trans)) {
-		err = PTR_ERR(clnt->trans);
-		clnt->trans = NULL;
+	err = clnt->trans_mod->create(clnt, dev_name, options);
+	if (err)
 		goto error;
-	}
 
 	if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
 		clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
@@ -233,11 +229,8 @@ void p9_client_destroy(struct p9_client *clnt)
 
 	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 
-	if (clnt->trans) {
-		clnt->trans->close(clnt->trans);
-		kfree(clnt->trans);
-		clnt->trans = NULL;
-	}
+	if (clnt->trans_mod)
+		clnt->trans_mod->close(clnt);
 
 	v9fs_put_trans(clnt->trans_mod);
 
@@ -254,7 +247,7 @@ EXPORT_SYMBOL(p9_client_destroy);
 void p9_client_disconnect(struct p9_client *clnt)
 {
 	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
-	clnt->trans->status = Disconnected;
+	clnt->status = Disconnected;
 }
 EXPORT_SYMBOL(p9_client_disconnect);
 

net/9p/mod.c

@@ -29,6 +29,7 @@
 #include <net/9p/9p.h>
 #include <linux/fs.h>
 #include <linux/parser.h>
+#include <net/9p/client.h>
 #include <net/9p/transport.h>
 #include <linux/list.h>
 #include <linux/spinlock.h>

net/9p/trans_fd.c

@@ -39,6 +39,7 @@
 #include <linux/file.h>
 #include <linux/parser.h>
 #include <net/9p/9p.h>
+#include <net/9p/client.h>
 #include <net/9p/transport.h>
 
 #define P9_PORT 564
@@ -146,7 +147,7 @@ struct p9_poll_wait {
  * @mux_list: list link for mux to manage multiple connections (?)
  * @msize: maximum size for connection (dup)
  * @extended: 9p2000.u flag (dup)
- * @trans: reference to transport instance for this connection
+ * @client: reference to client instance for this connection
  * @tagpool: id accounting for transactions
  * @err: error state
  * @req_list: accounting for requests which have been sent
@@ -171,7 +172,7 @@ struct p9_conn {
 	struct list_head mux_list;
 	int msize;
 	unsigned char extended;
-	struct p9_trans *trans;
+	struct p9_client *client;
 	struct p9_idpool *tagpool;
 	int err;
 	struct list_head req_list;
@@ -214,8 +215,8 @@ static void p9_read_work(struct work_struct *work);
 static void p9_write_work(struct work_struct *work);
 static void p9_pollwait(struct file *filp, wait_queue_head_t *wait_address,
 								poll_table *p);
-static int p9_fd_write(struct p9_trans *trans, void *v, int len);
-static int p9_fd_read(struct p9_trans *trans, void *v, int len);
+static int p9_fd_write(struct p9_client *client, void *v, int len);
+static int p9_fd_read(struct p9_client *client, void *v, int len);
 
 static DEFINE_SPINLOCK(p9_poll_lock);
 static LIST_HEAD(p9_poll_pending_list);
@@ -223,7 +224,7 @@ static struct workqueue_struct *p9_mux_wq;
 static struct task_struct *p9_poll_task;
 
 static void p9_conn_destroy(struct p9_conn *);
-static unsigned int p9_fd_poll(struct p9_trans *trans,
+static unsigned int p9_fd_poll(struct p9_client *client,
 						struct poll_table_struct *pt);
 
 #ifdef P9_NONBLOCK
@@ -271,27 +272,26 @@ static void p9_mux_poll_stop(struct p9_conn *m)
 
 /**
  * p9_conn_create - allocate and initialize the per-session mux data
- * @trans: transport structure
+ * @client: client instance
  *
  * Note: Creates the polling task if this is the first session.
  */
 
-static struct p9_conn *p9_conn_create(struct p9_trans *trans)
+static struct p9_conn *p9_conn_create(struct p9_client *client)
 {
 	int i, n;
 	struct p9_conn *m;
 
-	P9_DPRINTK(P9_DEBUG_MUX, "transport %p msize %d\n", trans,
-								trans->msize);
+	P9_DPRINTK(P9_DEBUG_MUX, "client %p msize %d\n", client, client->msize);
 	m = kzalloc(sizeof(struct p9_conn), GFP_KERNEL);
 	if (!m)
 		return ERR_PTR(-ENOMEM);
 
 	spin_lock_init(&m->lock);
 	INIT_LIST_HEAD(&m->mux_list);
-	m->msize = trans->msize;
-	m->extended = trans->extended;
-	m->trans = trans;
+	m->msize = client->msize;
+	m->extended = client->dotu;
+	m->client = client;
 	m->tagpool = p9_idpool_create();
 	if (IS_ERR(m->tagpool)) {
 		kfree(m);
@@ -305,7 +305,7 @@ static struct p9_conn *p9_conn_create(struct p9_trans *trans)
 	INIT_LIST_HEAD(&m->poll_pending_link);
 	init_poll_funcptr(&m->pt, p9_pollwait);
 
-	n = p9_fd_poll(trans, &m->pt);
+	n = p9_fd_poll(client, &m->pt);
 	if (n & POLLIN) {
 		P9_DPRINTK(P9_DEBUG_MUX, "mux %p can read\n", m);
 		set_bit(Rpending, &m->wsched);
@@ -345,7 +345,7 @@ static void p9_conn_destroy(struct p9_conn *m)
 
 	p9_conn_cancel(m, -ECONNRESET);
 
-	m->trans = NULL;
+	m->client = NULL;
 	p9_idpool_destroy(m->tagpool);
 	kfree(m);
 }
@@ -420,7 +420,7 @@ static void p9_poll_mux(struct p9_conn *m)
 	if (m->err < 0)
 		return;
 
-	n = p9_fd_poll(m->trans, NULL);
+	n = p9_fd_poll(m->client, NULL);
 	if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) {
 		P9_DPRINTK(P9_DEBUG_MUX, "error mux %p err %d\n", m, n);
 		if (n >= 0)
@@ -533,7 +533,7 @@ static void p9_write_work(struct work_struct *work)
 	P9_DPRINTK(P9_DEBUG_MUX, "mux %p pos %d size %d\n", m, m->wpos,
 								m->wsize);
 	clear_bit(Wpending, &m->wsched);
-	err = p9_fd_write(m->trans, m->wbuf + m->wpos, m->wsize - m->wpos);
+	err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos);
 	P9_DPRINTK(P9_DEBUG_MUX, "mux %p sent %d bytes\n", m, err);
 	if (err == -EAGAIN) {
 		clear_bit(Wworksched, &m->wsched);
@@ -555,7 +555,7 @@ static void p9_write_work(struct work_struct *work)
 		if (test_and_clear_bit(Wpending, &m->wsched))
 			n = POLLOUT;
 		else
-			n = p9_fd_poll(m->trans, NULL);
+			n = p9_fd_poll(m->client, NULL);
 
 		if (n & POLLOUT) {
 			P9_DPRINTK(P9_DEBUG_MUX, "schedule write work %p\n", m);
@@ -640,7 +640,7 @@ static void p9_read_work(struct work_struct *work)
 	}
 
 	clear_bit(Rpending, &m->wsched);
-	err = p9_fd_read(m->trans, m->rbuf + m->rpos, m->msize - m->rpos);
+	err = p9_fd_read(m->client, m->rbuf + m->rpos, m->msize - m->rpos);
 	P9_DPRINTK(P9_DEBUG_MUX, "mux %p got %d bytes\n", m, err);
 	if (err == -EAGAIN) {
 		clear_bit(Rworksched, &m->wsched);
@@ -735,7 +735,7 @@ static void p9_read_work(struct work_struct *work)
 		if (test_and_clear_bit(Rpending, &m->wsched))
 			n = POLLIN;
 		else
-			n = p9_fd_poll(m->trans, NULL);
+			n = p9_fd_poll(m->client, NULL);
 
 		if (n & POLLIN) {
 			P9_DPRINTK(P9_DEBUG_MUX, "schedule read work %p\n", m);
@@ -819,7 +819,7 @@ static struct p9_req *p9_send_request(struct p9_conn *m,
 	if (test_and_clear_bit(Wpending, &m->wsched))
 		n = POLLOUT;
 	else
-		n = p9_fd_poll(m->trans, NULL);
+		n = p9_fd_poll(m->client, NULL);
 
 	if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched))
 		queue_work(p9_mux_wq, &m->wq);
@@ -933,16 +933,16 @@ p9_conn_rpc_cb(struct p9_req *req, void *a)
 /**
  * p9_fd_rpc- sends 9P request and waits until a response is available.
  *	The function can be interrupted.
- * @t: transport data
+ * @client: client instance
  * @tc: request to be sent
  * @rc: pointer where a pointer to the response is stored
  *
  */
 
 int
-p9_fd_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
+p9_fd_rpc(struct p9_client *client, struct p9_fcall *tc, struct p9_fcall **rc)
 {
-	struct p9_trans_fd *p = t->priv;
+	struct p9_trans_fd *p = client->trans;
 	struct p9_conn *m = p->conn;
 	int err, sigpending;
 	unsigned long flags;
@@ -975,7 +975,7 @@ p9_fd_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
 	if (r.err < 0)
 		err = r.err;
 
-	if (err == -ERESTARTSYS && m->trans->status == Connected
+	if (err == -ERESTARTSYS && client->status == Connected
 							&& m->err == 0) {
 		if (p9_mux_flush_request(m, req)) {
 			/* wait until we get response of the flush message */
@@ -984,7 +984,7 @@ p9_fd_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
 				err = wait_event_interruptible(r.wqueue,
 					r.rcall || r.err);
 			} while (!r.rcall && !r.err && err == -ERESTARTSYS &&
-				m->trans->status == Connected && !m->err);
+				client->status == Connected && !m->err);
 
 			err = -ERESTARTSYS;
 		}
@@ -1133,7 +1133,7 @@ static int parse_opts(char *params, struct p9_fd_opts *opts)
 	return 0;
 }
 
-static int p9_fd_open(struct p9_trans *trans, int rfd, int wfd)
+static int p9_fd_open(struct p9_client *client, int rfd, int wfd)
 {
 	struct p9_trans_fd *ts = kmalloc(sizeof(struct p9_trans_fd),
 					   GFP_KERNEL);
@@ -1151,13 +1151,13 @@ static int p9_fd_open(struct p9_trans *trans, int rfd, int wfd)
 		return -EIO;
 	}
 
-	trans->priv = ts;
-	trans->status = Connected;
+	client->trans = ts;
+	client->status = Connected;
 
 	return 0;
 }
 
-static int p9_socket_open(struct p9_trans *trans, struct socket *csocket)
+static int p9_socket_open(struct p9_client *client, struct socket *csocket)
 {
 	int fd, ret;
 
@@ -1168,33 +1168,33 @@ static int p9_socket_open(struct p9_trans *trans, struct socket *csocket)
 		return fd;
 	}
 
-	ret = p9_fd_open(trans, fd, fd);
+	ret = p9_fd_open(client, fd, fd);
 	if (ret < 0) {
 		P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to open fd\n");
 		sockfd_put(csocket);
 		return ret;
 	}
 
-	((struct p9_trans_fd *)trans->priv)->rd->f_flags |= O_NONBLOCK;
+	((struct p9_trans_fd *)client->trans)->rd->f_flags |= O_NONBLOCK;
 
 	return 0;
 }
 
 /**
  * p9_fd_read- read from a fd
- * @trans: transport instance state
+ * @client: client instance
  * @v: buffer to receive data into
  * @len: size of receive buffer
  *
  */
 
-static int p9_fd_read(struct p9_trans *trans, void *v, int len)
+static int p9_fd_read(struct p9_client *client, void *v, int len)
 {
 	int ret;
 	struct p9_trans_fd *ts = NULL;
 
-	if (trans && trans->status != Disconnected)
-		ts = trans->priv;
+	if (client && client->status != Disconnected)
+		ts = client->trans;
 
 	if (!ts)
 		return -EREMOTEIO;
@@ -1204,26 +1204,26 @@ static int p9_fd_read(struct p9_trans *trans, void *v, int len)
 
 	ret = kernel_read(ts->rd, ts->rd->f_pos, v, len);
 	if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN)
-		trans->status = Disconnected;
+		client->status = Disconnected;
 	return ret;
 }
 
 /**
  * p9_fd_write - write to a socket
- * @trans: transport instance state
+ * @client: client instance
  * @v: buffer to send data from
  * @len: size of send buffer
  *
  */
 
-static int p9_fd_write(struct p9_trans *trans, void *v, int len)
+static int p9_fd_write(struct p9_client *client, void *v, int len)
 {
 	int ret;
 	mm_segment_t oldfs;
 	struct p9_trans_fd *ts = NULL;
 
-	if (trans && trans->status != Disconnected)
-		ts = trans->priv;
+	if (client && client->status != Disconnected)
+		ts = client->trans;
 
 	if (!ts)
 		return -EREMOTEIO;
@@ -1238,18 +1238,18 @@ static int p9_fd_write(struct p9_trans *trans, void *v, int len)
 	set_fs(oldfs);
 
 	if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN)
-		trans->status = Disconnected;
+		client->status = Disconnected;
 	return ret;
 }
 
 static unsigned int
-p9_fd_poll(struct p9_trans *trans, struct poll_table_struct *pt)
+p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt)
 {
 	int ret, n;
 	struct p9_trans_fd *ts = NULL;
 
-	if (trans && trans->status == Connected)
-		ts = trans->priv;
+	if (client && client->status == Connected)
+		ts = client->trans;
 
 	if (!ts)
 		return -EREMOTEIO;
@@ -1275,30 +1275,31 @@ p9_fd_poll(struct p9_trans *trans, struct poll_table_struct *pt)
 }
 
 /**
- * p9_fd_close - shutdown socket
- * @trans: private socket structure
+ * p9_fd_close - shutdown file descriptor transport
+ * @client: client instance
  *
  */
 
-static void p9_fd_close(struct p9_trans *trans)
+static void p9_fd_close(struct p9_client *client)
 {
 	struct p9_trans_fd *ts;
 
-	if (!trans)
+	if (!client)
 		return;
 
-	ts = xchg(&trans->priv, NULL);
-
+	ts = client->trans;
 	if (!ts)
 		return;
 
+	client->status = Disconnected;
+
 	p9_conn_destroy(ts->conn);
 
-	trans->status = Disconnected;
 	if (ts->rd)
 		fput(ts->rd);
 	if (ts->wr)
 		fput(ts->wr);
+
 	kfree(ts);
 }
 
@@ -1319,31 +1320,23 @@ static inline int valid_ipaddr4(const char *buf)
 	return 0;
 }
 
-static struct p9_trans *
-p9_trans_create_tcp(const char *addr, char *args, int msize, unsigned char dotu)
+static int
+p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args)
 {
 	int err;
-	struct p9_trans *trans;
 	struct socket *csocket;
 	struct sockaddr_in sin_server;
 	struct p9_fd_opts opts;
-	struct p9_trans_fd *p;
+	struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */
 
 	err = parse_opts(args, &opts);
 	if (err < 0)
-		return ERR_PTR(err);
+		return err;
 
 	if (valid_ipaddr4(addr) < 0)
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 
 	csocket = NULL;
-	trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL);
-	if (!trans)
-		return ERR_PTR(-ENOMEM);
-	trans->msize = msize;
-	trans->extended = dotu;
-	trans->rpc = p9_fd_rpc;
-	trans->close = p9_fd_close;
 
 	sin_server.sin_family = AF_INET;
 	sin_server.sin_addr.s_addr = in_aton(addr);
@@ -1366,45 +1359,38 @@ p9_trans_create_tcp(const char *addr, char *args, int msize, unsigned char dotu)
 		goto error;
 	}
 
-	err = p9_socket_open(trans, csocket);
+	err = p9_socket_open(client, csocket);
 	if (err < 0)
 		goto error;
 
-	p = (struct p9_trans_fd *) trans->priv;
-	p->conn = p9_conn_create(trans);
+	p = (struct p9_trans_fd *) client->trans;
+	p->conn = p9_conn_create(client);
 	if (IS_ERR(p->conn)) {
 		err = PTR_ERR(p->conn);
 		p->conn = NULL;
 		goto error;
 	}
 
-	return trans;
+	return 0;
 
 error:
 	if (csocket)
 		sock_release(csocket);
 
-	kfree(trans);
-	return ERR_PTR(err);
+	kfree(p);
+
+	return err;
 }
 
-static struct p9_trans *
-p9_trans_create_unix(const char *addr, char *args, int msize,
-							unsigned char dotu)
+static int
+p9_fd_create_unix(struct p9_client *client, const char *addr, char *args)
 {
 	int err;
 	struct socket *csocket;
 	struct sockaddr_un sun_server;
-	struct p9_trans *trans;
-	struct p9_trans_fd *p;
+	struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */
 
 	csocket = NULL;
-	trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL);
-	if (!trans)
-		return ERR_PTR(-ENOMEM);
-
-	trans->rpc = p9_fd_rpc;
-	trans->close = p9_fd_close;
 
 	if (strlen(addr) > UNIX_PATH_MAX) {
 		P9_EPRINTK(KERN_ERR, "p9_trans_unix: address too long: %s\n",
@@ -1425,79 +1411,68 @@ p9_trans_create_unix(const char *addr, char *args, int msize,
 		goto error;
 	}
 
-	err = p9_socket_open(trans, csocket);
+	err = p9_socket_open(client, csocket);
 	if (err < 0)
 		goto error;
 
-	trans->msize = msize;
-	trans->extended = dotu;
-	p = (struct p9_trans_fd *) trans->priv;
-	p->conn = p9_conn_create(trans);
+	p = (struct p9_trans_fd *) client->trans;
+	p->conn = p9_conn_create(client);
 	if (IS_ERR(p->conn)) {
 		err = PTR_ERR(p->conn);
 		p->conn = NULL;
 		goto error;
 	}
 
-	return trans;
+	return 0;
 
 error:
 	if (csocket)
 		sock_release(csocket);
 
-	kfree(trans);
-	return ERR_PTR(err);
+	kfree(p);
+	return err;
 }
 
-static struct p9_trans *
-p9_trans_create_fd(const char *name, char *args, int msize,
-							unsigned char extended)
+static int
+p9_fd_create(struct p9_client *client, const char *addr, char *args)
 {
 	int err;
-	struct p9_trans *trans;
 	struct p9_fd_opts opts;
-	struct p9_trans_fd *p;
+	struct p9_trans_fd *p = NULL; /* this get allocated in p9_fd_open */
 
 	parse_opts(args, &opts);
 
 	if (opts.rfd == ~0 || opts.wfd == ~0) {
 		printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n");
-		return ERR_PTR(-ENOPROTOOPT);
+		return -ENOPROTOOPT;
 	}
 
-	trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL);
-	if (!trans)
-		return ERR_PTR(-ENOMEM);
-
-	trans->rpc = p9_fd_rpc;
-	trans->close = p9_fd_close;
-
-	err = p9_fd_open(trans, opts.rfd, opts.wfd);
+	err = p9_fd_open(client, opts.rfd, opts.wfd);
 	if (err < 0)
 		goto error;
 
-	trans->msize = msize;
-	trans->extended = extended;
-	p = (struct p9_trans_fd *) trans->priv;
-	p->conn = p9_conn_create(trans);
+	p = (struct p9_trans_fd *) client->trans;
+	p->conn = p9_conn_create(client);
 	if (IS_ERR(p->conn)) {
 		err = PTR_ERR(p->conn);
 		p->conn = NULL;
 		goto error;
 	}
 
-	return trans;
+	return 0;
 
 error:
-	kfree(trans);
-	return ERR_PTR(err);
+	kfree(p);
+	return err;
 }
 
 static struct p9_trans_module p9_tcp_trans = {
 	.name = "tcp",
 	.maxsize = MAX_SOCK_BUF,
 	.def = 1,
-	.create = p9_trans_create_tcp,
+	.create = p9_fd_create_tcp,
+	.close = p9_fd_close,
+	.rpc = p9_fd_rpc,
 	.owner = THIS_MODULE,
 };
 
@@ -1505,7 +1480,9 @@ static struct p9_trans_module p9_unix_trans = {
 	.name = "unix",
 	.maxsize = MAX_SOCK_BUF,
 	.def = 0,
-	.create = p9_trans_create_unix,
+	.create = p9_fd_create_unix,
+	.close = p9_fd_close,
+	.rpc = p9_fd_rpc,
 	.owner = THIS_MODULE,
 };
 
@@ -1513,7 +1490,9 @@ static struct p9_trans_module p9_fd_trans = {
 	.name = "fd",
 	.maxsize = MAX_SOCK_BUF,
 	.def = 0,
-	.create = p9_trans_create_fd,
+	.create = p9_fd_create,
+	.close = p9_fd_close,
+	.rpc = p9_fd_rpc,
 	.owner = THIS_MODULE,
 };
 

net/9p/trans_virtio.c

@@ -41,6 +41,7 @@
 #include <linux/file.h>
 #include <net/9p/9p.h>
 #include <linux/parser.h>
+#include <net/9p/client.h>
 #include <net/9p/transport.h>
 #include <linux/scatterlist.h>
 #include <linux/virtio.h>
@@ -55,7 +56,6 @@ static int chan_index;
 
 #define P9_INIT_MAXTAG	16
 
-
 /**
  * enum p9_req_status_t - virtio request status
  * @REQ_STATUS_IDLE: request slot unused
@@ -197,9 +197,9 @@ static unsigned int rest_of_page(void *data)
  *
  */
 
-static void p9_virtio_close(struct p9_trans *trans)
+static void p9_virtio_close(struct p9_client *client)
 {
-	struct virtio_chan *chan = trans->priv;
+	struct virtio_chan *chan = client->trans;
 	int count;
 	unsigned long flags;
 
@@ -215,7 +215,7 @@ static void p9_virtio_close(struct p9_trans *trans)
 	chan->inuse = false;
 	mutex_unlock(&virtio_9p_lock);
 
-	kfree(trans);
+	client->trans = NULL;
 }
 
 /**
@@ -292,17 +292,17 @@ pack_sg_list(struct scatterlist *sg, int start, int limit, char *data,
  */
 
 static int
-p9_virtio_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
+p9_virtio_rpc(struct p9_client *c, struct p9_fcall *tc, struct p9_fcall **rc)
 {
 	int in, out;
 	int n, err, size;
-	struct virtio_chan *chan = t->priv;
+	struct virtio_chan *chan = c->trans;
 	char *rdata;
 	struct p9_req_t *req;
 	unsigned long flags;
 
 	if (*rc == NULL) {
-		*rc = kmalloc(sizeof(struct p9_fcall) + t->msize, GFP_KERNEL);
+		*rc = kmalloc(sizeof(struct p9_fcall) + c->msize, GFP_KERNEL);
 		if (!*rc)
 			return -ENOMEM;
 	}
@@ -325,7 +325,7 @@ p9_virtio_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
 	P9_DPRINTK(P9_DEBUG_TRANS, "9p debug: virtio rpc tag %d\n", n);
 
 	out = pack_sg_list(chan->sg, 0, VIRTQUEUE_NUM, tc->sdata, tc->size);
-	in = pack_sg_list(chan->sg, out, VIRTQUEUE_NUM-out, rdata, t->msize);
+	in = pack_sg_list(chan->sg, out, VIRTQUEUE_NUM-out, rdata, c->msize);
 
 	req->status = REQ_STATUS_SENT;
 
@@ -341,7 +341,7 @@ p9_virtio_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
 
 	size = le32_to_cpu(*(__le32 *) rdata);
 
-	err = p9_deserialize_fcall(rdata, size, *rc, t->extended);
+	err = p9_deserialize_fcall(rdata, size, *rc, c->dotu);
 	if (err < 0) {
 		P9_DPRINTK(P9_DEBUG_TRANS,
 			"9p debug: virtio rpc deserialize returned %d\n", err);
@@ -352,8 +352,8 @@ p9_virtio_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
 	if ((p9_debug_level&P9_DEBUG_FCALL) == P9_DEBUG_FCALL) {
 		char buf[150];
 
-		p9_printfcall(buf, sizeof(buf), *rc, t->extended);
-		printk(KERN_NOTICE ">>> %p %s\n", t, buf);
+		p9_printfcall(buf, sizeof(buf), *rc, c->dotu);
+		printk(KERN_NOTICE ">>> %p %s\n", c, buf);
 	}
 #endif
 
@@ -422,10 +422,9 @@ static int p9_virtio_probe(struct virtio_device *vdev)
 
 /**
  * p9_virtio_create - allocate a new virtio channel
+ * @client: client instance invoking this transport
  * @devname: string identifying the channel to connect to (unused)
  * @args: args passed from sys_mount() for per-transport options (unused)
- * @msize: requested maximum packet size
- * @extended: 9p2000.u enabled flag
  *
  * This sets up a transport channel for 9p communication.  Right now
  * we only match the first available channel, but eventually we couldlook up
@@ -441,11 +440,9 @@ static int p9_virtio_probe(struct virtio_device *vdev)
  *
  */
 
-static struct p9_trans *
-p9_virtio_create(const char *devname, char *args, int msize,
-							unsigned char extended)
+static int
+p9_virtio_create(struct p9_client *client, const char *devname, char *args)
 {
-	struct p9_trans *trans;
 	struct virtio_chan *chan = channels;
 	int index = 0;
 
@@ -463,30 +460,21 @@ p9_virtio_create(const char *devname, char *args, int msize,
 
 	if (index >= MAX_9P_CHAN) {
 		printk(KERN_ERR "9p: no channels available\n");
-		return ERR_PTR(-ENODEV);
+		return -ENODEV;
 	}
 
 	chan->tagpool = p9_idpool_create();
 	if (IS_ERR(chan->tagpool)) {
 		printk(KERN_ERR "9p: couldn't allocate tagpool\n");
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 	}
 	p9_idpool_get(chan->tagpool); /* reserve tag 0 */
 	chan->max_tag = 0;
 	chan->reqs = NULL;
 
-	trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL);
-	if (!trans) {
-		printk(KERN_ERR "9p: couldn't allocate transport\n");
-		return ERR_PTR(-ENOMEM);
-	}
-	trans->extended = extended;
-	trans->msize = msize;
-	trans->close = p9_virtio_close;
-	trans->rpc = p9_virtio_rpc;
-	trans->priv = chan;
+	client->trans = (void *)chan;
 
-	return trans;
+	return 0;
 }
 
 /**
@@ -526,6 +514,8 @@ static struct virtio_driver p9_virtio_drv = {
 static struct p9_trans_module p9_virtio_trans = {
 	.name = "virtio",
 	.create = p9_virtio_create,
+	.close = p9_virtio_close,
+	.rpc = p9_virtio_rpc,
 	.maxsize = PAGE_SIZE*16,
 	.def = 0,
 	.owner = THIS_MODULE,