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: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 92 insertions, 113 deletions

diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index f845923..d09389f 100644
--- a/net/9p/trans_fd.c
+++ b/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 @@ again:
 	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 @@ again:
 		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,
 };