From f75580c4afb72c156746b3fc1ec977b1a85d3dee Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Mon, 15 Feb 2010 17:27:00 +0000
Subject: net/9p: Add multi channel support.

This is needed for supporting multiple mount points.

We can find out the device names to be used with mount by checking

/sys/devices/virtio-pci/virtio*/device file

if the device file have value 9 then the specific virtio device can
be used for mounting.

ex:
 #cat /sys/devices/virtio-pci/virtio1/device
 9

now we can mount using
# mount -t 9p -o trans=virtio virtio1  /mnt/

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/include/linux/virtio_9p.h b/include/linux/virtio_9p.h
index 095e10d..7a615c3 100644
--- a/include/linux/virtio_9p.h
+++ b/include/linux/virtio_9p.h
@@ -6,6 +6,6 @@
 #include <linux/virtio_config.h>
 
 /* Maximum number of virtio channels per partition (1 for now) */
-#define MAX_9P_CHAN	1
+#define MAX_9P_CHAN	10
 
 #endif /* _LINUX_VIRTIO_9P_H */
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index cb50f4a..df924e5 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -296,13 +296,15 @@ p9_virtio_create(struct p9_client *client, const char *devname, char *args)
 
 	mutex_lock(&virtio_9p_lock);
 	while (index < MAX_9P_CHAN) {
-		if (chan->initialized && !chan->inuse) {
-			chan->inuse = true;
-			break;
-		} else {
-			index++;
-			chan = &channels[index];
+		if (chan->initialized &&
+			!strcmp(devname, dev_name(&chan->vdev->dev))) {
+			if (!chan->inuse) {
+				chan->inuse = true;
+				break;
+			}
 		}
+		index++;
+		chan = &channels[index];
 	}
 	mutex_unlock(&virtio_9p_lock);
 
-- 
cgit v0.10.2


From 37c1209d413242d9560e343c040777049a8dd869 Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Mon, 15 Feb 2010 17:27:01 +0000
Subject: net/9p: Remove MAX_9P_CHAN limit

Use a list to track the channel instead of statically
allocated array

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/include/linux/virtio_9p.h b/include/linux/virtio_9p.h
index 7a615c3..3322750 100644
--- a/include/linux/virtio_9p.h
+++ b/include/linux/virtio_9p.h
@@ -5,7 +5,4 @@
 #include <linux/virtio_ids.h>
 #include <linux/virtio_config.h>
 
-/* Maximum number of virtio channels per partition (1 for now) */
-#define MAX_9P_CHAN	10
-
 #endif /* _LINUX_VIRTIO_9P_H */
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index df924e5..05918d3 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -49,8 +49,6 @@
 
 /* a single mutex to manage channel initialization and attachment */
 static DEFINE_MUTEX(virtio_9p_lock);
-/* global which tracks highest initialized channel */
-static int chan_index;
 
 /**
  * struct virtio_chan - per-instance transport information
@@ -68,8 +66,7 @@ static int chan_index;
  *
  */
 
-static struct virtio_chan {
-	bool initialized;
+struct virtio_chan {
 	bool inuse;
 
 	spinlock_t lock;
@@ -80,7 +77,11 @@ static struct virtio_chan {
 
 	/* Scatterlist: can be too big for stack. */
 	struct scatterlist sg[VIRTQUEUE_NUM];
-} channels[MAX_9P_CHAN];
+
+	struct list_head chan_list;
+};
+
+static struct list_head virtio_chan_list;
 
 /* How many bytes left in this page. */
 static unsigned int rest_of_page(void *data)
@@ -217,9 +218,7 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
  * p9_virtio_probe - probe for existence of 9P virtio channels
  * @vdev: virtio device to probe
  *
- * This probes for existing virtio channels.  At present only
- * a single channel is in use, so in the future more work may need
- * to be done here.
+ * This probes for existing virtio channels.
  *
  */
 
@@ -227,16 +226,10 @@ static int p9_virtio_probe(struct virtio_device *vdev)
 {
 	int err;
 	struct virtio_chan *chan;
-	int index;
 
-	mutex_lock(&virtio_9p_lock);
-	index = chan_index++;
-	chan = &channels[index];
-	mutex_unlock(&virtio_9p_lock);
-
-	if (chan_index > MAX_9P_CHAN) {
-		printk(KERN_ERR "9p: virtio: Maximum channels exceeded\n");
-		BUG();
+	chan = kmalloc(sizeof(struct virtio_chan), GFP_KERNEL);
+	if (!chan) {
+		printk(KERN_ERR "9p: Failed to allocate virtio 9P channel\n");
 		err = -ENOMEM;
 		goto fail;
 	}
@@ -255,15 +248,15 @@ static int p9_virtio_probe(struct virtio_device *vdev)
 	sg_init_table(chan->sg, VIRTQUEUE_NUM);
 
 	chan->inuse = false;
-	chan->initialized = true;
+	mutex_lock(&virtio_9p_lock);
+	list_add_tail(&chan->chan_list, &virtio_chan_list);
+	mutex_unlock(&virtio_9p_lock);
 	return 0;
 
 out_free_vq:
 	vdev->config->del_vqs(vdev);
+	kfree(chan);
 fail:
-	mutex_lock(&virtio_9p_lock);
-	chan_index--;
-	mutex_unlock(&virtio_9p_lock);
 	return err;
 }
 
@@ -280,35 +273,27 @@ fail:
  * We use a simple reference count mechanism to ensure that only a single
  * mount has a channel open at a time.
  *
- * Bugs: doesn't allow identification of a specific channel
- * to allocate, channels are allocated sequentially. This was
- * a pragmatic decision to get things rolling, but ideally some
- * way of identifying the channel to attach to would be nice
- * if we are going to support multiple channels.
- *
  */
 
 static int
 p9_virtio_create(struct p9_client *client, const char *devname, char *args)
 {
-	struct virtio_chan *chan = channels;
-	int index = 0;
+	struct virtio_chan *chan;
+	int found = 0;
 
 	mutex_lock(&virtio_9p_lock);
-	while (index < MAX_9P_CHAN) {
-		if (chan->initialized &&
-			!strcmp(devname, dev_name(&chan->vdev->dev))) {
+	list_for_each_entry(chan, &virtio_chan_list, chan_list) {
+		if (!strcmp(devname, dev_name(&chan->vdev->dev))) {
 			if (!chan->inuse) {
 				chan->inuse = true;
+				found = 1;
 				break;
 			}
 		}
-		index++;
-		chan = &channels[index];
 	}
 	mutex_unlock(&virtio_9p_lock);
 
-	if (index >= MAX_9P_CHAN) {
+	if (!found) {
 		printk(KERN_ERR "9p: no channels available\n");
 		return -ENODEV;
 	}
@@ -331,11 +316,13 @@ static void p9_virtio_remove(struct virtio_device *vdev)
 	struct virtio_chan *chan = vdev->priv;
 
 	BUG_ON(chan->inuse);
+	vdev->config->del_vqs(vdev);
+
+	mutex_lock(&virtio_9p_lock);
+	list_del(&chan->chan_list);
+	mutex_unlock(&virtio_9p_lock);
+	kfree(chan);
 
-	if (chan->initialized) {
-		vdev->config->del_vqs(vdev);
-		chan->initialized = false;
-	}
 }
 
 static struct virtio_device_id id_table[] = {
@@ -366,10 +353,7 @@ static struct p9_trans_module p9_virtio_trans = {
 /* The standard init function */
 static int __init p9_virtio_init(void)
 {
-	int count;
-
-	for (count = 0; count < MAX_9P_CHAN; count++)
-		channels[count].initialized = false;
+	INIT_LIST_HEAD(&virtio_chan_list);
 
 	v9fs_register_trans(&p9_virtio_trans);
 	return register_virtio_driver(&p9_virtio_drv);
-- 
cgit v0.10.2


From c1a7c2262035e83a8f70ebe1328b3451702cf51b Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Mon, 15 Feb 2010 17:27:02 +0000
Subject: net/9p: Handle mount errors correctly.

With this patch we have

# mount -t 9p -o trans=virtio virtio2 /mnt/
# mount -t 9p -o trans=virtio virtio2 /mnt/
mount: virtio2 already mounted or /mnt/ busy
mount: according to mtab, virtio2 is already mounted on /mnt
# mount -t 9p -o trans=virtio virtio3 /mnt/ -o debug=0xfff
mount: special device virtio3 does not exist

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index 05918d3..0aaed48 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -279,6 +279,7 @@ static int
 p9_virtio_create(struct p9_client *client, const char *devname, char *args)
 {
 	struct virtio_chan *chan;
+	int ret = -ENOENT;
 	int found = 0;
 
 	mutex_lock(&virtio_9p_lock);
@@ -289,13 +290,14 @@ p9_virtio_create(struct p9_client *client, const char *devname, char *args)
 				found = 1;
 				break;
 			}
+			ret = -EBUSY;
 		}
 	}
 	mutex_unlock(&virtio_9p_lock);
 
 	if (!found) {
 		printk(KERN_ERR "9p: no channels available\n");
-		return -ENODEV;
+		return ret;
 	}
 
 	client->trans = (void *)chan;
-- 
cgit v0.10.2


From dd6102fbd917889384d89bc427e98e85e8fda000 Mon Sep 17 00:00:00 2001
From: Sripathi Kodi <sripathik@in.ibm.com>
Date: Fri, 5 Mar 2010 18:48:00 +0000
Subject: 9P2010.L handshake: Add VFS flags

Add 9P2000.u and 9P2010.L protocol flags to V9FS VFS

This patch adds 9P2000.u and 9P2010.L protocol flags into V9FS VFS side code
and removes the single flag used for 'extended'.

Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index 14d9442..08b2eb1 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -151,7 +151,7 @@ struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
 			if (access == V9FS_ACCESS_SINGLE)
 				return ERR_PTR(-EPERM);
 
-			if (v9fs_extended(v9ses))
+			if (v9fs_proto_dotu(v9ses))
 				uname = NULL;
 			else
 				uname = v9ses->uname;
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index 7d6c213..247f10a 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -241,7 +241,7 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 	list_add(&v9ses->slist, &v9fs_sessionlist);
 	spin_unlock(&v9fs_sessionlist_lock);
 
-	v9ses->flags = V9FS_EXTENDED | V9FS_ACCESS_USER;
+	v9ses->flags = V9FS_PROTO_2000U | V9FS_ACCESS_USER;
 	strcpy(v9ses->uname, V9FS_DEFUSER);
 	strcpy(v9ses->aname, V9FS_DEFANAME);
 	v9ses->uid = ~0;
@@ -263,12 +263,12 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 	}
 
 	if (!v9ses->clnt->dotu)
-		v9ses->flags &= ~V9FS_EXTENDED;
+		v9ses->flags &= ~V9FS_PROTO_2000U;
 
 	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
 
 	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
-	if (!v9fs_extended(v9ses) &&
+	if (!v9fs_proto_dotu(v9ses) &&
 		((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
 
 		v9ses->flags &= ~V9FS_ACCESS_MASK;
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index 019f4cc..79000bf 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -23,7 +23,8 @@
 
 /**
  * enum p9_session_flags - option flags for each 9P session
- * @V9FS_EXTENDED: whether or not to use 9P2000.u extensions
+ * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
+ * @V9FS_PROTO_2010L: whether or not to use 9P2010.l extensions
  * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
  * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
  * @V9FS_ACCESS_ANY: use a single attach for all users
@@ -32,11 +33,12 @@
  * Session flags reflect options selected by users at mount time
  */
 enum p9_session_flags {
-	V9FS_EXTENDED		= 0x01,
-	V9FS_ACCESS_SINGLE	= 0x02,
-	V9FS_ACCESS_USER	= 0x04,
-	V9FS_ACCESS_ANY		= 0x06,
-	V9FS_ACCESS_MASK	= 0x06,
+	V9FS_PROTO_2000U	= 0x01,
+	V9FS_PROTO_2010L	= 0x02,
+	V9FS_ACCESS_SINGLE	= 0x04,
+	V9FS_ACCESS_USER	= 0x08,
+	V9FS_ACCESS_ANY		= 0x0C,
+	V9FS_ACCESS_MASK	= 0x0C,
 };
 
 /* possible values of ->cache */
@@ -121,7 +123,12 @@ static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
 	return (inode->i_sb->s_fs_info);
 }
 
-static inline int v9fs_extended(struct v9fs_session_info *v9ses)
+static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
 {
-	return v9ses->flags & V9FS_EXTENDED;
+	return v9ses->flags & V9FS_PROTO_2000U;
+}
+
+static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
+{
+	return v9ses->flags & V9FS_PROTO_2010L;
 }
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 74a0461..3612268 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -61,7 +61,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 
 	P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p \n", inode, file);
 	v9ses = v9fs_inode2v9ses(inode);
-	omode = v9fs_uflags2omode(file->f_flags, v9fs_extended(v9ses));
+	omode = v9fs_uflags2omode(file->f_flags, v9fs_proto_dotu(v9ses));
 	fid = file->private_data;
 	if (!fid) {
 		fid = v9fs_fid_clone(file->f_path.dentry);
@@ -77,7 +77,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 			i_size_write(inode, 0);
 			inode->i_blocks = 0;
 		}
-		if ((file->f_flags & O_APPEND) && (!v9fs_extended(v9ses)))
+		if ((file->f_flags & O_APPEND) && (!v9fs_proto_dotu(v9ses)))
 			generic_file_llseek(file, 0, SEEK_END);
 	}
 
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index a407fa3..d3d3c3c 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -60,7 +60,7 @@ static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
 	res = mode & 0777;
 	if (S_ISDIR(mode))
 		res |= P9_DMDIR;
-	if (v9fs_extended(v9ses)) {
+	if (v9fs_proto_dotu(v9ses)) {
 		if (S_ISLNK(mode))
 			res |= P9_DMSYMLINK;
 		if (v9ses->nodev == 0) {
@@ -102,21 +102,21 @@ static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
 
 	if ((mode & P9_DMDIR) == P9_DMDIR)
 		res |= S_IFDIR;
-	else if ((mode & P9_DMSYMLINK) && (v9fs_extended(v9ses)))
+	else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
 		res |= S_IFLNK;
-	else if ((mode & P9_DMSOCKET) && (v9fs_extended(v9ses))
+	else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
 		 && (v9ses->nodev == 0))
 		res |= S_IFSOCK;
-	else if ((mode & P9_DMNAMEDPIPE) && (v9fs_extended(v9ses))
+	else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
 		 && (v9ses->nodev == 0))
 		res |= S_IFIFO;
-	else if ((mode & P9_DMDEVICE) && (v9fs_extended(v9ses))
+	else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
 		 && (v9ses->nodev == 0))
 		res |= S_IFBLK;
 	else
 		res |= S_IFREG;
 
-	if (v9fs_extended(v9ses)) {
+	if (v9fs_proto_dotu(v9ses)) {
 		if ((mode & P9_DMSETUID) == P9_DMSETUID)
 			res |= S_ISUID;
 
@@ -265,7 +265,7 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode)
 	case S_IFBLK:
 	case S_IFCHR:
 	case S_IFSOCK:
-		if (!v9fs_extended(v9ses)) {
+		if (!v9fs_proto_dotu(v9ses)) {
 			P9_DPRINTK(P9_DEBUG_ERROR,
 				   "special files without extended mode\n");
 			err = -EINVAL;
@@ -278,7 +278,7 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode)
 		inode->i_fop = &v9fs_file_operations;
 		break;
 	case S_IFLNK:
-		if (!v9fs_extended(v9ses)) {
+		if (!v9fs_proto_dotu(v9ses)) {
 			P9_DPRINTK(P9_DEBUG_ERROR,
 				   "extended modes used w/o 9P2000.u\n");
 			err = -EINVAL;
@@ -288,7 +288,7 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode)
 		break;
 	case S_IFDIR:
 		inc_nlink(inode);
-		if (v9fs_extended(v9ses))
+		if (v9fs_proto_dotu(v9ses))
 			inode->i_op = &v9fs_dir_inode_operations_ext;
 		else
 			inode->i_op = &v9fs_dir_inode_operations;
@@ -575,7 +575,8 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 		flags = O_RDWR;
 
 	fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
-				v9fs_uflags2omode(flags, v9fs_extended(v9ses)));
+				v9fs_uflags2omode(flags,
+						v9fs_proto_dotu(v9ses)));
 	if (IS_ERR(fid)) {
 		err = PTR_ERR(fid);
 		fid = NULL;
@@ -858,7 +859,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	if (iattr->ia_valid & ATTR_SIZE)
 		wstat.length = iattr->ia_size;
 
-	if (v9fs_extended(v9ses)) {
+	if (v9fs_proto_dotu(v9ses)) {
 		if (iattr->ia_valid & ATTR_UID)
 			wstat.n_uid = iattr->ia_uid;
 
@@ -897,7 +898,7 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 	inode->i_uid = v9ses->dfltuid;
 	inode->i_gid = v9ses->dfltgid;
 
-	if (v9fs_extended(v9ses)) {
+	if (v9fs_proto_dotu(v9ses)) {
 		inode->i_uid = stat->n_uid;
 		inode->i_gid = stat->n_gid;
 	}
@@ -976,7 +977,7 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
 	if (IS_ERR(fid))
 		return PTR_ERR(fid);
 
-	if (!v9fs_extended(v9ses))
+	if (!v9fs_proto_dotu(v9ses))
 		return -EBADF;
 
 	st = p9_client_stat(fid);
@@ -1066,7 +1067,7 @@ static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
 	struct p9_fid *fid;
 
 	v9ses = v9fs_inode2v9ses(dir);
-	if (!v9fs_extended(v9ses)) {
+	if (!v9fs_proto_dotu(v9ses)) {
 		P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
 		return -EPERM;
 	}
-- 
cgit v0.10.2


From 0fb80abd911a7cb1e6548b5279568dc1e8949702 Mon Sep 17 00:00:00 2001
From: Sripathi Kodi <sripathik@in.ibm.com>
Date: Fri, 5 Mar 2010 18:49:11 +0000
Subject: 9P2010.L handshake: Add mount option

Add new mount V9FS mount option to specify protocol version

This patch adds a new mount option to specify protocol version.
With this option it is possible to use "-o version=" switch to
specify 9P protocol version to use. Valid options for version
are:
9p2000
9p2000.u
9p2010.L

Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index fb00b32..d40f8c5 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -29,6 +29,19 @@
 /* Number of requests per row */
 #define P9_ROW_MAXTAG 255
 
+/** enum p9_proto_versions - 9P protocol versions
+ * @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u
+ * @p9_proto_2000u: 9P2000.u extension
+ * @p9_proto_2010L: 9P2010.L extension
+ */
+
+enum p9_proto_versions{
+	p9_proto_legacy = 0,
+	p9_proto_2000u = 1,
+	p9_proto_2010L = 2,
+};
+
+
 /**
  * enum p9_trans_status - different states of underlying transports
  * @Connected: transport is connected and healthy
@@ -111,6 +124,7 @@ struct p9_req_t {
  * @lock: protect @fidlist
  * @msize: maximum data size negotiated by protocol
  * @dotu: extension flags negotiated by protocol
+ * @proto_version: 9P protocol version to use
  * @trans_mod: module API instantiated with this client
  * @trans: tranport instance state and API
  * @conn: connection state information used by trans_fd
@@ -138,6 +152,7 @@ struct p9_client {
 	spinlock_t lock; /* protect client structure */
 	int msize;
 	unsigned char dotu;
+	unsigned char proto_version;
 	struct p9_trans_module *trans_mod;
 	enum p9_trans_status status;
 	void *trans;
diff --git a/net/9p/client.c b/net/9p/client.c
index 09d4f1e..3b5f3c9 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -46,6 +46,7 @@ enum {
 	Opt_msize,
 	Opt_trans,
 	Opt_legacy,
+	Opt_version,
 	Opt_err,
 };
 
@@ -53,9 +54,30 @@ static const match_table_t tokens = {
 	{Opt_msize, "msize=%u"},
 	{Opt_legacy, "noextend"},
 	{Opt_trans, "trans=%s"},
+	{Opt_version, "version=%s"},
 	{Opt_err, NULL},
 };
 
+/* Interpret mount option for protocol version */
+static unsigned char get_protocol_version(const substring_t *name)
+{
+	unsigned char version = -EINVAL;
+	if (!strncmp("9p2000", name->from, name->to-name->from)) {
+		version = p9_proto_legacy;
+		P9_DPRINTK(P9_DEBUG_9P, "Protocol version: Legacy\n");
+	} else if (!strncmp("9p2000.u", name->from, name->to-name->from)) {
+		version = p9_proto_2000u;
+		P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
+	} else if (!strncmp("9p2010.L", name->from, name->to-name->from)) {
+		version = p9_proto_2010L;
+		P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2010.L\n");
+	} else {
+		P9_DPRINTK(P9_DEBUG_ERROR, "Unknown protocol version %s. ",
+							name->from);
+	}
+	return version;
+}
+
 static struct p9_req_t *
 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 
@@ -120,6 +142,12 @@ static int parse_opts(char *opts, struct p9_client *clnt)
 		case Opt_legacy:
 			clnt->dotu = 0;
 			break;
+		case Opt_version:
+			ret = get_protocol_version(&args[0]);
+			if (ret == -EINVAL)
+				goto free_and_return;
+			clnt->proto_version = ret;
+			break;
 		default:
 			continue;
 		}
-- 
cgit v0.10.2


From 342fee1d5c7dfa05f4e14ec1e583df4553b09776 Mon Sep 17 00:00:00 2001
From: Sripathi Kodi <sripathik@in.ibm.com>
Date: Fri, 5 Mar 2010 18:50:14 +0000
Subject: 9P2010.L handshake: Remove "dotu" variable

Removes 'dotu' variable and make everything dependent
on 'proto_version' field.

Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index 247f10a..6c7f6a2 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -262,7 +262,7 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 		goto error;
 	}
 
-	if (!v9ses->clnt->dotu)
+	if (!p9_is_proto_dotu(v9ses->clnt))
 		v9ses->flags &= ~V9FS_PROTO_2000U;
 
 	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
index 15cce53..6580aa4 100644
--- a/fs/9p/vfs_dir.c
+++ b/fs/9p/vfs_dir.c
@@ -135,7 +135,7 @@ static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir)
 		while (rdir->head < rdir->tail) {
 			err = p9stat_read(rdir->buf + rdir->head,
 						buflen - rdir->head, &st,
-						fid->clnt->dotu);
+						fid->clnt->proto_version);
 			if (err) {
 				P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err);
 				err = -EIO;
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index d40f8c5..52e1fff 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -151,7 +151,6 @@ struct p9_req_t {
 struct p9_client {
 	spinlock_t lock; /* protect client structure */
 	int msize;
-	unsigned char dotu;
 	unsigned char proto_version;
 	struct p9_trans_module *trans_mod;
 	enum p9_trans_status status;
@@ -224,5 +223,7 @@ int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int);
 int p9stat_read(char *, int, struct p9_wstat *, int);
 void p9stat_free(struct p9_wstat *);
 
+int p9_is_proto_dotu(struct p9_client *clnt);
+int p9_is_proto_dotl(struct p9_client *clnt);
 
 #endif /* NET_9P_CLIENT_H */
diff --git a/net/9p/client.c b/net/9p/client.c
index 3b5f3c9..9994676 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -58,6 +58,18 @@ static const match_table_t tokens = {
 	{Opt_err, NULL},
 };
 
+inline int p9_is_proto_dotl(struct p9_client *clnt)
+{
+	return (clnt->proto_version == p9_proto_2010L);
+}
+EXPORT_SYMBOL(p9_is_proto_dotl);
+
+inline int p9_is_proto_dotu(struct p9_client *clnt)
+{
+	return (clnt->proto_version == p9_proto_2000u);
+}
+EXPORT_SYMBOL(p9_is_proto_dotu);
+
 /* Interpret mount option for protocol version */
 static unsigned char get_protocol_version(const substring_t *name)
 {
@@ -97,7 +109,7 @@ static int parse_opts(char *opts, struct p9_client *clnt)
 	int option;
 	int ret = 0;
 
-	clnt->dotu = 1;
+	clnt->proto_version = p9_proto_2000u;
 	clnt->msize = 8192;
 
 	if (!opts)
@@ -140,7 +152,7 @@ static int parse_opts(char *opts, struct p9_client *clnt)
 			}
 			break;
 		case Opt_legacy:
-			clnt->dotu = 0;
+			clnt->proto_version = p9_proto_legacy;
 			break;
 		case Opt_version:
 			ret = get_protocol_version(&args[0]);
@@ -438,14 +450,15 @@ static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 		int ecode;
 		char *ename;
 
-		err = p9pdu_readf(req->rc, c->dotu, "s?d", &ename, &ecode);
+		err = p9pdu_readf(req->rc, c->proto_version, "s?d",
+							&ename, &ecode);
 		if (err) {
 			P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
 									err);
 			return err;
 		}
 
-		if (c->dotu)
+		if (p9_is_proto_dotu(c))
 			err = -ecode;
 
 		if (!err || !IS_ERR_VALUE(err))
@@ -543,7 +556,7 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 	/* marshall the data */
 	p9pdu_prepare(req->tc, tag, type);
 	va_start(ap, fmt);
-	err = p9pdu_vwritef(req->tc, c->dotu, fmt, ap);
+	err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 	va_end(ap);
 	p9pdu_finalize(req->tc);
 
@@ -655,14 +668,14 @@ int p9_client_version(struct p9_client *c)
 	char *version;
 	int msize;
 
-	P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d extended %d\n",
-							c->msize, c->dotu);
+	P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
+						c->msize, c->proto_version);
 	req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize,
-				c->dotu ? "9P2000.u" : "9P2000");
+				p9_is_proto_dotu(c) ? "9P2000.u" : "9P2000");
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
-	err = p9pdu_readf(req->rc, c->dotu, "ds", &msize, &version);
+	err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 	if (err) {
 		P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
 		p9pdu_dump(1, req->rc);
@@ -670,10 +683,10 @@ int p9_client_version(struct p9_client *c)
 	}
 
 	P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
-	if (!memcmp(version, "9P2000.u", 8))
-		c->dotu = 1;
-	else if (!memcmp(version, "9P2000", 6))
-		c->dotu = 0;
+	if (!strncmp(version, "9P2000.u", 8))
+		c->proto_version = p9_proto_2000u;
+	else if (!strncmp(version, "9P2000", 6))
+		c->proto_version = p9_proto_legacy;
 	else {
 		err = -EREMOTEIO;
 		goto error;
@@ -728,8 +741,8 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
 		goto put_trans;
 	}
 
-	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d dotu %d\n",
-		clnt, clnt->trans_mod, clnt->msize, clnt->dotu);
+	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
+		clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
 
 	err = clnt->trans_mod->create(clnt, dev_name, options);
 	if (err)
@@ -812,7 +825,7 @@ struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		p9_free_req(clnt, req);
@@ -861,7 +874,7 @@ p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		p9_free_req(clnt, req);
@@ -919,7 +932,7 @@ struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "R", &nwqids, &wqids);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		p9_free_req(clnt, req);
@@ -980,7 +993,7 @@ int p9_client_open(struct p9_fid *fid, int mode)
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		goto free_and_error;
@@ -1025,7 +1038,7 @@ int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		goto free_and_error;
@@ -1126,7 +1139,7 @@ p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "D", &count, &dataptr);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		goto free_and_error;
@@ -1187,7 +1200,7 @@ p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "d", &count);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		goto free_and_error;
@@ -1227,7 +1240,7 @@ struct p9_wstat *p9_client_stat(struct p9_fid *fid)
 		goto error;
 	}
 
-	err = p9pdu_readf(req->rc, clnt->dotu, "wS", &ignored, ret);
+	err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
 	if (err) {
 		p9pdu_dump(1, req->rc);
 		p9_free_req(clnt, req);
@@ -1254,7 +1267,7 @@ error:
 }
 EXPORT_SYMBOL(p9_client_stat);
 
-static int p9_client_statsize(struct p9_wstat *wst, int optional)
+static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
 {
 	int ret;
 
@@ -1273,7 +1286,7 @@ static int p9_client_statsize(struct p9_wstat *wst, int optional)
 	if (wst->muid)
 		ret += strlen(wst->muid);
 
-	if (optional) {
+	if (proto_version == p9_proto_2000u) {
 		ret += 2+4+4+4;	/* extension[s] n_uid[4] n_gid[4] n_muid[4] */
 		if (wst->extension)
 			ret += strlen(wst->extension);
@@ -1290,7 +1303,7 @@ int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
 
 	err = 0;
 	clnt = fid->clnt;
-	wst->size = p9_client_statsize(wst, clnt->dotu);
+	wst->size = p9_client_statsize(wst, clnt->proto_version);
 	P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
 	P9_DPRINTK(P9_DEBUG_9P,
 		"     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
diff --git a/net/9p/protocol.c b/net/9p/protocol.c
index fc70147..94f5a8f 100644
--- a/net/9p/protocol.c
+++ b/net/9p/protocol.c
@@ -52,7 +52,7 @@
 #endif
 
 static int
-p9pdu_writef(struct p9_fcall *pdu, int optional, const char *fmt, ...);
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
 
 #ifdef CONFIG_NET_9P_DEBUG
 void
@@ -144,7 +144,8 @@ pdu_write_u(struct p9_fcall *pdu, const char __user *udata, size_t size)
 */
 
 static int
-p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
+p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
+	va_list ap)
 {
 	const char *ptr;
 	int errcode = 0;
@@ -194,7 +195,8 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				int16_t len;
 				int size;
 
-				errcode = p9pdu_readf(pdu, optional, "w", &len);
+				errcode = p9pdu_readf(pdu, proto_version,
+								"w", &len);
 				if (errcode)
 					break;
 
@@ -217,7 +219,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				struct p9_qid *qid =
 				    va_arg(ap, struct p9_qid *);
 
-				errcode = p9pdu_readf(pdu, optional, "bdq",
+				errcode = p9pdu_readf(pdu, proto_version, "bdq",
 						      &qid->type, &qid->version,
 						      &qid->path);
 			}
@@ -230,7 +232,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
 									-1;
 				errcode =
-				    p9pdu_readf(pdu, optional,
+				    p9pdu_readf(pdu, proto_version,
 						"wwdQdddqssss?sddd",
 						&stbuf->size, &stbuf->type,
 						&stbuf->dev, &stbuf->qid,
@@ -250,7 +252,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				void **data = va_arg(ap, void **);
 
 				errcode =
-				    p9pdu_readf(pdu, optional, "d", count);
+				    p9pdu_readf(pdu, proto_version, "d", count);
 				if (!errcode) {
 					*count =
 					    MIN(*count,
@@ -263,8 +265,8 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				int16_t *nwname = va_arg(ap, int16_t *);
 				char ***wnames = va_arg(ap, char ***);
 
-				errcode =
-				    p9pdu_readf(pdu, optional, "w", nwname);
+				errcode = p9pdu_readf(pdu, proto_version,
+								"w", nwname);
 				if (!errcode) {
 					*wnames =
 					    kmalloc(sizeof(char *) * *nwname,
@@ -278,7 +280,8 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 
 					for (i = 0; i < *nwname; i++) {
 						errcode =
-						    p9pdu_readf(pdu, optional,
+						    p9pdu_readf(pdu,
+								proto_version,
 								"s",
 								&(*wnames)[i]);
 						if (errcode)
@@ -306,7 +309,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				*wqids = NULL;
 
 				errcode =
-				    p9pdu_readf(pdu, optional, "w", nwqid);
+				    p9pdu_readf(pdu, proto_version, "w", nwqid);
 				if (!errcode) {
 					*wqids =
 					    kmalloc(*nwqid *
@@ -321,7 +324,8 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 
 					for (i = 0; i < *nwqid; i++) {
 						errcode =
-						    p9pdu_readf(pdu, optional,
+						    p9pdu_readf(pdu,
+								proto_version,
 								"Q",
 								&(*wqids)[i]);
 						if (errcode)
@@ -336,7 +340,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 			}
 			break;
 		case '?':
-			if (!optional)
+			if (proto_version != p9_proto_2000u)
 				return 0;
 			break;
 		default:
@@ -352,7 +356,8 @@ p9pdu_vreadf(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 }
 
 int
-p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
+p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+	va_list ap)
 {
 	const char *ptr;
 	int errcode = 0;
@@ -389,7 +394,8 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				if (sptr)
 					len = MIN(strlen(sptr), USHORT_MAX);
 
-				errcode = p9pdu_writef(pdu, optional, "w", len);
+				errcode = p9pdu_writef(pdu, proto_version,
+								"w", len);
 				if (!errcode && pdu_write(pdu, sptr, len))
 					errcode = -EFAULT;
 			}
@@ -398,7 +404,7 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				const struct p9_qid *qid =
 				    va_arg(ap, const struct p9_qid *);
 				errcode =
-				    p9pdu_writef(pdu, optional, "bdq",
+				    p9pdu_writef(pdu, proto_version, "bdq",
 						 qid->type, qid->version,
 						 qid->path);
 			} break;
@@ -406,7 +412,7 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				const struct p9_wstat *stbuf =
 				    va_arg(ap, const struct p9_wstat *);
 				errcode =
-				    p9pdu_writef(pdu, optional,
+				    p9pdu_writef(pdu, proto_version,
 						 "wwdQdddqssss?sddd",
 						 stbuf->size, stbuf->type,
 						 stbuf->dev, &stbuf->qid,
@@ -421,8 +427,8 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				int32_t count = va_arg(ap, int32_t);
 				const void *data = va_arg(ap, const void *);
 
-				errcode =
-				    p9pdu_writef(pdu, optional, "d", count);
+				errcode = p9pdu_writef(pdu, proto_version, "d",
+									count);
 				if (!errcode && pdu_write(pdu, data, count))
 					errcode = -EFAULT;
 			}
@@ -431,8 +437,8 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				int32_t count = va_arg(ap, int32_t);
 				const char __user *udata =
 						va_arg(ap, const void __user *);
-				errcode =
-				    p9pdu_writef(pdu, optional, "d", count);
+				errcode = p9pdu_writef(pdu, proto_version, "d",
+									count);
 				if (!errcode && pdu_write_u(pdu, udata, count))
 					errcode = -EFAULT;
 			}
@@ -441,14 +447,15 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				int16_t nwname = va_arg(ap, int);
 				const char **wnames = va_arg(ap, const char **);
 
-				errcode =
-				    p9pdu_writef(pdu, optional, "w", nwname);
+				errcode = p9pdu_writef(pdu, proto_version, "w",
+									nwname);
 				if (!errcode) {
 					int i;
 
 					for (i = 0; i < nwname; i++) {
 						errcode =
-						    p9pdu_writef(pdu, optional,
+						    p9pdu_writef(pdu,
+								proto_version,
 								 "s",
 								 wnames[i]);
 						if (errcode)
@@ -462,14 +469,15 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 				struct p9_qid *wqids =
 				    va_arg(ap, struct p9_qid *);
 
-				errcode =
-				    p9pdu_writef(pdu, optional, "w", nwqid);
+				errcode = p9pdu_writef(pdu, proto_version, "w",
+									nwqid);
 				if (!errcode) {
 					int i;
 
 					for (i = 0; i < nwqid; i++) {
 						errcode =
-						    p9pdu_writef(pdu, optional,
+						    p9pdu_writef(pdu,
+								proto_version,
 								 "Q",
 								 &wqids[i]);
 						if (errcode)
@@ -479,7 +487,7 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 			}
 			break;
 		case '?':
-			if (!optional)
+			if (proto_version != p9_proto_2000u)
 				return 0;
 			break;
 		default:
@@ -494,32 +502,32 @@ p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap)
 	return errcode;
 }
 
-int p9pdu_readf(struct p9_fcall *pdu, int optional, const char *fmt, ...)
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
 {
 	va_list ap;
 	int ret;
 
 	va_start(ap, fmt);
-	ret = p9pdu_vreadf(pdu, optional, fmt, ap);
+	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
 	va_end(ap);
 
 	return ret;
 }
 
 static int
-p9pdu_writef(struct p9_fcall *pdu, int optional, const char *fmt, ...)
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
 {
 	va_list ap;
 	int ret;
 
 	va_start(ap, fmt);
-	ret = p9pdu_vwritef(pdu, optional, fmt, ap);
+	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
 	va_end(ap);
 
 	return ret;
 }
 
-int p9stat_read(char *buf, int len, struct p9_wstat *st, int dotu)
+int p9stat_read(char *buf, int len, struct p9_wstat *st, int proto_version)
 {
 	struct p9_fcall fake_pdu;
 	int ret;
@@ -529,7 +537,7 @@ int p9stat_read(char *buf, int len, struct p9_wstat *st, int dotu)
 	fake_pdu.sdata = buf;
 	fake_pdu.offset = 0;
 
-	ret = p9pdu_readf(&fake_pdu, dotu, "S", st);
+	ret = p9pdu_readf(&fake_pdu, proto_version, "S", st);
 	if (ret) {
 		P9_DPRINTK(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
 		p9pdu_dump(1, &fake_pdu);
diff --git a/net/9p/protocol.h b/net/9p/protocol.h
index ccde462..2431c0f 100644
--- a/net/9p/protocol.h
+++ b/net/9p/protocol.h
@@ -25,9 +25,9 @@
  *
  */
 
-int
-p9pdu_vwritef(struct p9_fcall *pdu, int optional, const char *fmt, va_list ap);
-int p9pdu_readf(struct p9_fcall *pdu, int optional, const char *fmt, ...);
+int p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+								va_list ap);
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
 int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type);
 int p9pdu_finalize(struct p9_fcall *pdu);
 void p9pdu_dump(int, struct p9_fcall *);
-- 
cgit v0.10.2


From c5a7697da9775f7a0e122fa23180becc311772d1 Mon Sep 17 00:00:00 2001
From: Sripathi Kodi <sripathik@in.ibm.com>
Date: Fri, 5 Mar 2010 18:51:04 +0000
Subject: 9P2010.L handshake: .L protocol negotiation

This patch adds 9P2010.L protocol negotiation with the server

Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/net/9p/client.c b/net/9p/client.c
index 9994676..bde9f3d 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -670,8 +670,25 @@ int p9_client_version(struct p9_client *c)
 
 	P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 						c->msize, c->proto_version);
-	req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize,
-				p9_is_proto_dotu(c) ? "9P2000.u" : "9P2000");
+
+	switch (c->proto_version) {
+	case p9_proto_2010L:
+		req = p9_client_rpc(c, P9_TVERSION, "ds",
+					c->msize, "9P2010.L");
+		break;
+	case p9_proto_2000u:
+		req = p9_client_rpc(c, P9_TVERSION, "ds",
+					c->msize, "9P2000.u");
+		break;
+	case p9_proto_legacy:
+		req = p9_client_rpc(c, P9_TVERSION, "ds",
+					c->msize, "9P2000");
+		break;
+	default:
+		return -EINVAL;
+		break;
+	}
+
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
@@ -683,7 +700,9 @@ int p9_client_version(struct p9_client *c)
 	}
 
 	P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
-	if (!strncmp(version, "9P2000.u", 8))
+	if (!strncmp(version, "9P2010.L", 8))
+		c->proto_version = p9_proto_2010L;
+	else if (!strncmp(version, "9P2000.u", 8))
 		c->proto_version = p9_proto_2000u;
 	else if (!strncmp(version, "9P2000", 6))
 		c->proto_version = p9_proto_legacy;
-- 
cgit v0.10.2


From 5717144a01d701614cfdb15f09ed562d720cf3db Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Fri, 5 Mar 2010 14:43:43 -0600
Subject: fs/9p: Add hardlink support to .u extension

For regular file and directories we put the link
count in th extension field in a tagged string format.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index d3d3c3c..5fe45d6 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -887,6 +887,8 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 	struct super_block *sb)
 {
 	char ext[32];
+	char tag_name[14];
+	unsigned int i_nlink;
 	struct v9fs_session_info *v9ses = sb->s_fs_info;
 
 	inode->i_nlink = 1;
@@ -902,7 +904,22 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 		inode->i_uid = stat->n_uid;
 		inode->i_gid = stat->n_gid;
 	}
-
+	if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
+		if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
+			/*
+			 * Hadlink support got added later to
+			 * to the .u extension. So there can be
+			 * server out there that doesn't support
+			 * this even with .u extension. So check
+			 * for non NULL stat->extension
+			 */
+			strncpy(ext, stat->extension, sizeof(ext));
+			/* HARDLINKCOUNT %u */
+			sscanf(ext, "%13s %u", tag_name, &i_nlink);
+			if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
+				inode->i_nlink = i_nlink;
+		}
+	}
 	inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
 	if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
 		char type = 0;
-- 
cgit v0.10.2