9p: Reorganization of 9p file system code

This patchset moves non-filesystem interfaces of v9fs from fs/9p to net/9p.
It moves the transport, packet marshalling and connection layers to net/9p
leaving only the VFS related files in fs/9p.  This work is being done in
preparation for in-kernel 9p servers as well as alternate 9p clients (other
than VFS).

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

4 files changed, 603 insertions, 0 deletions

diff --git a/include/net/9p/9p.h b/include/net/9p/9p.h
new file mode 100644
index 000000000000..88884d39f28f
--- /dev/null
+++ b/include/net/9p/9p.h
@@ -0,0 +1,417 @@
+/*
+ * include/net/9p/9p.h
+ *
+ * 9P protocol definitions.
+ *
+ *  Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  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
+ *
+ */
+
+#ifndef NET_9P_H
+#define NET_9P_H
+
+#ifdef CONFIG_NET_9P_DEBUG
+
+#define P9_DEBUG_ERROR		(1<<0)
+#define P9_DEBUG_9P	        (1<<2)
+#define P9_DEBUG_VFS	        (1<<3)
+#define P9_DEBUG_CONV		(1<<4)
+#define P9_DEBUG_MUX		(1<<5)
+#define P9_DEBUG_TRANS		(1<<6)
+#define P9_DEBUG_SLABS	      	(1<<7)
+#define P9_DEBUG_FCALL		(1<<8)
+
+extern unsigned int p9_debug_level;
+
+#define P9_DPRINTK(level, format, arg...) \
+do {  \
+	if ((p9_debug_level & level) == level) \
+		printk(KERN_NOTICE "-- %s (%d): " \
+		format , __FUNCTION__, current->pid , ## arg); \
+} while (0)
+
+#define PRINT_FCALL_ERROR(s, fcall) P9_DPRINTK(P9_DEBUG_ERROR,   \
+	"%s: %.*s\n", s, fcall?fcall->params.rerror.error.len:0, \
+	fcall?fcall->params.rerror.error.str:"");
+
+#else
+#define P9_DPRINTK(level, format, arg...)  do { } while (0)
+#define PRINT_FCALL_ERROR(s, fcall) do { } while (0)
+#endif
+
+#define P9_EPRINTK(level, format, arg...) \
+do { \
+	printk(level "9p: %s (%d): " \
+		format , __FUNCTION__, current->pid , ## arg); \
+} while (0)
+
+
+/* Message Types */
+enum {
+	P9_TVERSION = 100,
+	P9_RVERSION,
+	P9_TAUTH = 102,
+	P9_RAUTH,
+	P9_TATTACH = 104,
+	P9_RATTACH,
+	P9_TERROR = 106,
+	P9_RERROR,
+	P9_TFLUSH = 108,
+	P9_RFLUSH,
+	P9_TWALK = 110,
+	P9_RWALK,
+	P9_TOPEN = 112,
+	P9_ROPEN,
+	P9_TCREATE = 114,
+	P9_RCREATE,
+	P9_TREAD = 116,
+	P9_RREAD,
+	P9_TWRITE = 118,
+	P9_RWRITE,
+	P9_TCLUNK = 120,
+	P9_RCLUNK,
+	P9_TREMOVE = 122,
+	P9_RREMOVE,
+	P9_TSTAT = 124,
+	P9_RSTAT,
+	P9_TWSTAT = 126,
+	P9_RWSTAT,
+};
+
+/* open modes */
+enum {
+	P9_OREAD = 0x00,
+	P9_OWRITE = 0x01,
+	P9_ORDWR = 0x02,
+	P9_OEXEC = 0x03,
+	P9_OEXCL = 0x04,
+	P9_OTRUNC = 0x10,
+	P9_OREXEC = 0x20,
+	P9_ORCLOSE = 0x40,
+	P9_OAPPEND = 0x80,
+};
+
+/* permissions */
+enum {
+	P9_DMDIR = 0x80000000,
+	P9_DMAPPEND = 0x40000000,
+	P9_DMEXCL = 0x20000000,
+	P9_DMMOUNT = 0x10000000,
+	P9_DMAUTH = 0x08000000,
+	P9_DMTMP = 0x04000000,
+	P9_DMSYMLINK = 0x02000000,
+	P9_DMLINK = 0x01000000,
+	/* 9P2000.u extensions */
+	P9_DMDEVICE = 0x00800000,
+	P9_DMNAMEDPIPE = 0x00200000,
+	P9_DMSOCKET = 0x00100000,
+	P9_DMSETUID = 0x00080000,
+	P9_DMSETGID = 0x00040000,
+};
+
+/* qid.types */
+enum {
+	P9_QTDIR = 0x80,
+	P9_QTAPPEND = 0x40,
+	P9_QTEXCL = 0x20,
+	P9_QTMOUNT = 0x10,
+	P9_QTAUTH = 0x08,
+	P9_QTTMP = 0x04,
+	P9_QTSYMLINK = 0x02,
+	P9_QTLINK = 0x01,
+	P9_QTFILE = 0x00,
+};
+
+#define P9_NOTAG	(u16)(~0)
+#define P9_NOFID	(u32)(~0)
+#define P9_MAXWELEM	16
+
+/* ample room for Twrite/Rread header */
+#define P9_IOHDRSZ	24
+
+struct p9_str {
+	u16 len;
+	char *str;
+};
+
+/* qids are the unique ID for a file (like an inode */
+struct p9_qid {
+	u8 type;
+	u32 version;
+	u64 path;
+};
+
+/* Plan 9 file metadata (stat) structure */
+struct p9_stat {
+	u16 size;
+	u16 type;
+	u32 dev;
+	struct p9_qid qid;
+	u32 mode;
+	u32 atime;
+	u32 mtime;
+	u64 length;
+	struct p9_str name;
+	struct p9_str uid;
+	struct p9_str gid;
+	struct p9_str muid;
+	struct p9_str extension;	/* 9p2000.u extensions */
+	u32 n_uid;			/* 9p2000.u extensions */
+	u32 n_gid;			/* 9p2000.u extensions */
+	u32 n_muid;			/* 9p2000.u extensions */
+};
+
+/* file metadata (stat) structure used to create Twstat message
+   The is similar to p9_stat, but the strings don't point to
+   the same memory block and should be freed separately
+*/
+struct p9_wstat {
+	u16 size;
+	u16 type;
+	u32 dev;
+	struct p9_qid qid;
+	u32 mode;
+	u32 atime;
+	u32 mtime;
+	u64 length;
+	char *name;
+	char *uid;
+	char *gid;
+	char *muid;
+	char *extension;	/* 9p2000.u extensions */
+	u32 n_uid;		/* 9p2000.u extensions */
+	u32 n_gid;		/* 9p2000.u extensions */
+	u32 n_muid;		/* 9p2000.u extensions */
+};
+
+/* Structures for Protocol Operations */
+struct p9_tversion {
+	u32 msize;
+	struct p9_str version;
+};
+
+struct p9_rversion {
+	u32 msize;
+	struct p9_str version;
+};
+
+struct p9_tauth {
+	u32 afid;
+	struct p9_str uname;
+	struct p9_str aname;
+};
+
+struct p9_rauth {
+	struct p9_qid qid;
+};
+
+struct p9_rerror {
+	struct p9_str error;
+	u32 errno;		/* 9p2000.u extension */
+};
+
+struct p9_tflush {
+	u16 oldtag;
+};
+
+struct p9_rflush {
+};
+
+struct p9_tattach {
+	u32 fid;
+	u32 afid;
+	struct p9_str uname;
+	struct p9_str aname;
+};
+
+struct p9_rattach {
+	struct p9_qid qid;
+};
+
+struct p9_twalk {
+	u32 fid;
+	u32 newfid;
+	u16 nwname;
+	struct p9_str wnames[16];
+};
+
+struct p9_rwalk {
+	u16 nwqid;
+	struct p9_qid wqids[16];
+};
+
+struct p9_topen {
+	u32 fid;
+	u8 mode;
+};
+
+struct p9_ropen {
+	struct p9_qid qid;
+	u32 iounit;
+};
+
+struct p9_tcreate {
+	u32 fid;
+	struct p9_str name;
+	u32 perm;
+	u8 mode;
+	struct p9_str extension;
+};
+
+struct p9_rcreate {
+	struct p9_qid qid;
+	u32 iounit;
+};
+
+struct p9_tread {
+	u32 fid;
+	u64 offset;
+	u32 count;
+};
+
+struct p9_rread {
+	u32 count;
+	u8 *data;
+};
+
+struct p9_twrite {
+	u32 fid;
+	u64 offset;
+	u32 count;
+	u8 *data;
+};
+
+struct p9_rwrite {
+	u32 count;
+};
+
+struct p9_tclunk {
+	u32 fid;
+};
+
+struct p9_rclunk {
+};
+
+struct p9_tremove {
+	u32 fid;
+};
+
+struct p9_rremove {
+};
+
+struct p9_tstat {
+	u32 fid;
+};
+
+struct p9_rstat {
+	struct p9_stat stat;
+};
+
+struct p9_twstat {
+	u32 fid;
+	struct p9_stat stat;
+};
+
+struct p9_rwstat {
+};
+
+/*
+  * fcall is the primary packet structure
+  *
+  */
+
+struct p9_fcall {
+	u32 size;
+	u8 id;
+	u16 tag;
+	void *sdata;
+
+	union {
+		struct p9_tversion tversion;
+		struct p9_rversion rversion;
+		struct p9_tauth tauth;
+		struct p9_rauth rauth;
+		struct p9_rerror rerror;
+		struct p9_tflush tflush;
+		struct p9_rflush rflush;
+		struct p9_tattach tattach;
+		struct p9_rattach rattach;
+		struct p9_twalk twalk;
+		struct p9_rwalk rwalk;
+		struct p9_topen topen;
+		struct p9_ropen ropen;
+		struct p9_tcreate tcreate;
+		struct p9_rcreate rcreate;
+		struct p9_tread tread;
+		struct p9_rread rread;
+		struct p9_twrite twrite;
+		struct p9_rwrite rwrite;
+		struct p9_tclunk tclunk;
+		struct p9_rclunk rclunk;
+		struct p9_tremove tremove;
+		struct p9_rremove rremove;
+		struct p9_tstat tstat;
+		struct p9_rstat rstat;
+		struct p9_twstat twstat;
+		struct p9_rwstat rwstat;
+	} params;
+};
+
+struct p9_idpool;
+
+int p9_deserialize_stat(void *buf, u32 buflen, struct p9_stat *stat,
+	int dotu);
+int p9_deserialize_fcall(void *buf, u32 buflen, struct p9_fcall *fc, int dotu);
+void p9_set_tag(struct p9_fcall *fc, u16 tag);
+struct p9_fcall *p9_create_tversion(u32 msize, char *version);
+struct p9_fcall *p9_create_tattach(u32 fid, u32 afid, char *uname,
+	char *aname);
+struct p9_fcall *p9_create_tauth(u32 afid, char *uname, char *aname);
+struct p9_fcall *p9_create_tflush(u16 oldtag);
+struct p9_fcall *p9_create_twalk(u32 fid, u32 newfid, u16 nwname,
+	char **wnames);
+struct p9_fcall *p9_create_topen(u32 fid, u8 mode);
+struct p9_fcall *p9_create_tcreate(u32 fid, char *name, u32 perm, u8 mode,
+	char *extension, int dotu);
+struct p9_fcall *p9_create_tread(u32 fid, u64 offset, u32 count);
+struct p9_fcall *p9_create_twrite(u32 fid, u64 offset, u32 count,
+	const char *data);
+struct p9_fcall *p9_create_twrite_u(u32 fid, u64 offset, u32 count,
+	const char __user *data);
+struct p9_fcall *p9_create_tclunk(u32 fid);
+struct p9_fcall *p9_create_tremove(u32 fid);
+struct p9_fcall *p9_create_tstat(u32 fid);
+struct p9_fcall *p9_create_twstat(u32 fid, struct p9_wstat *wstat,
+	int dotu);
+
+int p9_printfcall(char *buf, int buflen, struct p9_fcall *fc, int dotu);
+int p9_errstr2errno(char *errstr, int len);
+
+struct p9_idpool *p9_idpool_create(void);
+void p9_idpool_destroy(struct p9_idpool *);
+int p9_idpool_get(struct p9_idpool *p);
+void p9_idpool_put(int id, struct p9_idpool *p);
+int p9_idpool_check(int id, struct p9_idpool *p);
+
+int p9_error_init(void);
+int p9_errstr2errno(char *, int);
+int __init p9_sysctl_register(void);
+void __exit p9_sysctl_unregister(void);
+#endif /* NET_9P_H */
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
new file mode 100644
index 000000000000..d65ed7c69063
--- /dev/null
+++ b/include/net/9p/client.h
@@ -0,0 +1,80 @@
+/*
+ * include/net/9p/client.h
+ *
+ * 9P Client Definitions
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  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
+ *
+ */
+
+#ifndef NET_9P_CLIENT_H
+#define NET_9P_CLIENT_H
+
+struct p9_client {
+	spinlock_t lock; /* protect client structure */
+	int msize;
+	unsigned char dotu;
+	struct p9_transport *trans;
+	struct p9_conn *conn;
+
+	struct p9_idpool *fidpool;
+	struct list_head fidlist;
+};
+
+struct p9_fid {
+	struct p9_client *clnt;
+	u32 fid;
+	int mode;
+	struct p9_qid qid;
+	u32 iounit;
+	uid_t uid;
+	void *aux;
+
+	int rdir_fpos;
+	int rdir_pos;
+	struct p9_fcall *rdir_fcall;
+	struct list_head flist;
+	struct list_head dlist;	/* list of all fids attached to a dentry */
+};
+
+struct p9_client *p9_client_create(struct p9_transport *trans, int msize,
+								int dotu);
+void p9_client_destroy(struct p9_client *clnt);
+void p9_client_disconnect(struct p9_client *clnt);
+struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
+						     char *uname, char *aname);
+struct p9_fid *p9_client_auth(struct p9_client *clnt, char *uname, char *aname);
+struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
+								int clone);
+int p9_client_open(struct p9_fid *fid, int mode);
+int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
+							char *extension);
+int p9_client_clunk(struct p9_fid *fid);
+int p9_client_remove(struct p9_fid *fid);
+int p9_client_read(struct p9_fid *fid, char *data, u64 offset, u32 count);
+int p9_client_readn(struct p9_fid *fid, char *data, u64 offset, u32 count);
+int p9_client_write(struct p9_fid *fid, char *data, u64 offset, u32 count);
+int p9_client_uread(struct p9_fid *fid, char __user *data, u64 offset,
+								u32 count);
+int p9_client_uwrite(struct p9_fid *fid, const char __user *data, u64 offset,
+								u32 count);
+struct p9_stat *p9_client_stat(struct p9_fid *fid);
+int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst);
+struct p9_stat *p9_client_dirread(struct p9_fid *fid, u64 offset);
+
+#endif /* NET_9P_CLIENT_H */
diff --git a/include/net/9p/conn.h b/include/net/9p/conn.h
new file mode 100644
index 000000000000..583b6a2cb3df
--- /dev/null
+++ b/include/net/9p/conn.h
@@ -0,0 +1,57 @@
+/*
+ * include/net/9p/conn.h
+ *
+ * Connection Definitions
+ *
+ *  Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
+ *  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 version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  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
+ *
+ */
+
+#ifndef NET_9P_CONN_H
+#define NET_9P_CONN_H
+
+#undef P9_NONBLOCK
+
+struct p9_conn;
+struct p9_req;
+
+/**
+ * p9_mux_req_callback - callback function that is called when the
+ * response of a request is received. The callback is called from
+ * a workqueue and shouldn't block.
+ *
+ * @req - request
+ * @a - the pointer that was specified when the request was send to be
+ *      passed to the callback
+ */
+typedef void (*p9_conn_req_callback)(struct p9_req *req, void *a);
+
+struct p9_conn *p9_conn_create(struct p9_transport *trans, int msize,
+	unsigned char *dotu);
+void p9_conn_destroy(struct p9_conn *);
+int p9_conn_rpc(struct p9_conn *m, struct p9_fcall *tc, struct p9_fcall **rc);
+
+#ifdef P9_NONBLOCK
+int p9_conn_rpcnb(struct p9_conn *m, struct p9_fcall *tc,
+	p9_conn_req_callback cb, void *a);
+#endif /* P9_NONBLOCK */
+
+void p9_conn_cancel(struct p9_conn *m, int err);
+
+#endif /* NET_9P_CONN_H */
diff --git a/include/net/9p/transport.h b/include/net/9p/transport.h
new file mode 100644
index 000000000000..462d42279fb0
--- /dev/null
+++ b/include/net/9p/transport.h
@@ -0,0 +1,49 @@
+/*
+ * include/net/9p/transport.h
+ *
+ * Transport Definition
+ *
+ *  Copyright (C) 2005 by Latchesar Ionkov <lucho@ionkov.net>
+ *  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 version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  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
+ *
+ */
+
+#ifndef NET_9P_TRANSPORT_H
+#define NET_9P_TRANSPORT_H
+
+enum p9_transport_status {
+	Connected,
+	Disconnected,
+	Hung,
+};
+
+struct p9_transport {
+	enum p9_transport_status status;
+	void *priv;
+
+	int (*write) (struct p9_transport *, void *, int);
+	int (*read) (struct p9_transport *, void *, int);
+	void (*close) (struct p9_transport *);
+	unsigned int (*poll)(struct p9_transport *, struct poll_table_struct *);
+};
+
+struct p9_transport *p9_trans_create_tcp(const char *addr, int port);
+struct p9_transport *p9_trans_create_unix(const char *addr);
+struct p9_transport *p9_trans_create_fd(int rfd, int wfd);
+
+#endif /* NET_9P_TRANSPORT_H */