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[1/2] kvm tools: Copy net/9p/9p.h

Message ID 1305657337-2584-1-git-send-email-levinsasha928@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Sasha Levin May 17, 2011, 6:35 p.m. UTC
Header could not be included directly because among some minor
issues, the original header declared the same function twice:
int p9_errstr2errno(char *errstr, int len);
int p9_errstr2errno(char *, int);

A patch has been sent to 9P maintainers, this header should
be removed once the patch is in.

Until then, use a modified copy of the header.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
---
 tools/kvm/include/net/9p/9p.h |  735 +++++++++++++++++++++++++++++++++++++++++
 1 files changed, 735 insertions(+), 0 deletions(-)
 create mode 100644 tools/kvm/include/net/9p/9p.h
diff mbox

Patch

diff --git a/tools/kvm/include/net/9p/9p.h b/tools/kvm/include/net/9p/9p.h
new file mode 100644
index 0000000..cc11592
--- /dev/null
+++ b/tools/kvm/include/net/9p/9p.h
@@ -0,0 +1,735 @@ 
+/*
+ * 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
+
+#pragma pack(1)
+
+/**
+ * enum p9_debug_flags - bits for mount time debug parameter
+ * @P9_DEBUG_ERROR: more verbose error messages including original error string
+ * @P9_DEBUG_9P: 9P protocol tracing
+ * @P9_DEBUG_VFS: VFS API tracing
+ * @P9_DEBUG_CONV: protocol conversion tracing
+ * @P9_DEBUG_MUX: trace management of concurrent transactions
+ * @P9_DEBUG_TRANS: transport tracing
+ * @P9_DEBUG_SLABS: memory management tracing
+ * @P9_DEBUG_FCALL: verbose dump of protocol messages
+ * @P9_DEBUG_FID: fid allocation/deallocation tracking
+ * @P9_DEBUG_PKT: packet marshalling/unmarshalling
+ * @P9_DEBUG_FSC: FS-cache tracing
+ *
+ * These flags are passed at mount time to turn on various levels of
+ * verbosity and tracing which will be output to the system logs.
+ */
+
+enum p9_debug_flags {
+	P9_DEBUG_ERROR =	(1<<0),
+	P9_DEBUG_9P =		(1<<2),
+	P9_DEBUG_VFS =		(1<<3),
+	P9_DEBUG_CONV =		(1<<4),
+	P9_DEBUG_MUX =		(1<<5),
+	P9_DEBUG_TRANS =	(1<<6),
+	P9_DEBUG_SLABS =	(1<<7),
+	P9_DEBUG_FCALL =	(1<<8),
+	P9_DEBUG_FID =		(1<<9),
+	P9_DEBUG_PKT =		(1<<10),
+	P9_DEBUG_FSC =		(1<<11),
+};
+
+#ifdef CONFIG_NET_9P_DEBUG
+extern unsigned int p9_debug_level;
+
+#define P9_DPRINTK(level, format, arg...) \
+do {  \
+	if ((p9_debug_level & level) == level) {\
+		if (level == P9_DEBUG_9P) \
+			printk(KERN_NOTICE "(%8.8d) " \
+			format , task_pid_nr(current) , ## arg); \
+		else \
+			printk(KERN_NOTICE "-- %s (%d): " \
+			format , __func__, task_pid_nr(current) , ## arg); \
+	} \
+} while (0)
+
+#else
+#define P9_DPRINTK(level, format, arg...)  do { } while (0)
+#endif
+
+#define P9_EPRINTK(level, format, arg...) \
+do { \
+	printk(level "9p: %s (%d): " \
+		format , __func__, task_pid_nr(current), ## arg); \
+} while (0)
+
+/**
+ * enum p9_msg_t - 9P message types
+ * @P9_TLERROR: not used
+ * @P9_RLERROR: response for any failed request for 9P2000.L
+ * @P9_TSTATFS: file system status request
+ * @P9_RSTATFS: file system status response
+ * @P9_TSYMLINK: make symlink request
+ * @P9_RSYMLINK: make symlink response
+ * @P9_TMKNOD: create a special file object request
+ * @P9_RMKNOD: create a special file object response
+ * @P9_TLCREATE: prepare a handle for I/O on an new file for 9P2000.L
+ * @P9_RLCREATE: response with file access information for 9P2000.L
+ * @P9_TRENAME: rename request
+ * @P9_RRENAME: rename response
+ * @P9_TMKDIR: create a directory request
+ * @P9_RMKDIR: create a directory response
+ * @P9_TVERSION: version handshake request
+ * @P9_RVERSION: version handshake response
+ * @P9_TAUTH: request to establish authentication channel
+ * @P9_RAUTH: response with authentication information
+ * @P9_TATTACH: establish user access to file service
+ * @P9_RATTACH: response with top level handle to file hierarchy
+ * @P9_TERROR: not used
+ * @P9_RERROR: response for any failed request
+ * @P9_TFLUSH: request to abort a previous request
+ * @P9_RFLUSH: response when previous request has been cancelled
+ * @P9_TWALK: descend a directory hierarchy
+ * @P9_RWALK: response with new handle for position within hierarchy
+ * @P9_TOPEN: prepare a handle for I/O on an existing file
+ * @P9_ROPEN: response with file access information
+ * @P9_TCREATE: prepare a handle for I/O on a new file
+ * @P9_RCREATE: response with file access information
+ * @P9_TREAD: request to transfer data from a file or directory
+ * @P9_RREAD: response with data requested
+ * @P9_TWRITE: reuqest to transfer data to a file
+ * @P9_RWRITE: response with out much data was transferred to file
+ * @P9_TCLUNK: forget about a handle to an entity within the file system
+ * @P9_RCLUNK: response when server has forgotten about the handle
+ * @P9_TREMOVE: request to remove an entity from the hierarchy
+ * @P9_RREMOVE: response when server has removed the entity
+ * @P9_TSTAT: request file entity attributes
+ * @P9_RSTAT: response with file entity attributes
+ * @P9_TWSTAT: request to update file entity attributes
+ * @P9_RWSTAT: response when file entity attributes are updated
+ *
+ * There are 14 basic operations in 9P2000, paired as
+ * requests and responses.  The one special case is ERROR
+ * as there is no @P9_TERROR request for clients to transmit to
+ * the server, but the server may respond to any other request
+ * with an @P9_RERROR.
+ *
+ * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html
+ */
+
+enum p9_msg_t {
+	P9_TLERROR = 6,
+	P9_RLERROR,
+	P9_TSTATFS = 8,
+	P9_RSTATFS,
+	P9_TLOPEN = 12,
+	P9_RLOPEN,
+	P9_TLCREATE = 14,
+	P9_RLCREATE,
+	P9_TSYMLINK = 16,
+	P9_RSYMLINK,
+	P9_TMKNOD = 18,
+	P9_RMKNOD,
+	P9_TRENAME = 20,
+	P9_RRENAME,
+	P9_TREADLINK = 22,
+	P9_RREADLINK,
+	P9_TGETATTR = 24,
+	P9_RGETATTR,
+	P9_TSETATTR = 26,
+	P9_RSETATTR,
+	P9_TXATTRWALK = 30,
+	P9_RXATTRWALK,
+	P9_TXATTRCREATE = 32,
+	P9_RXATTRCREATE,
+	P9_TREADDIR = 40,
+	P9_RREADDIR,
+	P9_TFSYNC = 50,
+	P9_RFSYNC,
+	P9_TLOCK = 52,
+	P9_RLOCK,
+	P9_TGETLOCK = 54,
+	P9_RGETLOCK,
+	P9_TLINK = 70,
+	P9_RLINK,
+	P9_TMKDIR = 72,
+	P9_RMKDIR,
+	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,
+};
+
+/**
+ * enum p9_open_mode_t - 9P open modes
+ * @P9_OREAD: open file for reading only
+ * @P9_OWRITE: open file for writing only
+ * @P9_ORDWR: open file for reading or writing
+ * @P9_OEXEC: open file for execution
+ * @P9_OTRUNC: truncate file to zero-length before opening it
+ * @P9_OREXEC: close the file when an exec(2) system call is made
+ * @P9_ORCLOSE: remove the file when the file is closed
+ * @P9_OAPPEND: open the file and seek to the end
+ * @P9_OEXCL: only create a file, do not open it
+ *
+ * 9P open modes differ slightly from Posix standard modes.
+ * In particular, there are extra modes which specify different
+ * semantic behaviors than may be available on standard Posix
+ * systems.  For example, @P9_OREXEC and @P9_ORCLOSE are modes that
+ * most likely will not be issued from the Linux VFS client, but may
+ * be supported by servers.
+ *
+ * See Also: http://plan9.bell-labs.com/magic/man2html/2/open
+ */
+
+enum p9_open_mode_t {
+	P9_OREAD = 0x00,
+	P9_OWRITE = 0x01,
+	P9_ORDWR = 0x02,
+	P9_OEXEC = 0x03,
+	P9_OTRUNC = 0x10,
+	P9_OREXEC = 0x20,
+	P9_ORCLOSE = 0x40,
+	P9_OAPPEND = 0x80,
+	P9_OEXCL = 0x1000,
+};
+
+/**
+ * enum p9_perm_t - 9P permissions
+ * @P9_DMDIR: mode bite for directories
+ * @P9_DMAPPEND: mode bit for is append-only
+ * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed)
+ * @P9_DMMOUNT: mode bite for mount points
+ * @P9_DMAUTH: mode bit for authentication file
+ * @P9_DMTMP: mode bit for non-backed-up files
+ * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u)
+ * @P9_DMLINK: mode bit for hard-link (9P2000.u)
+ * @P9_DMDEVICE: mode bit for device files (9P2000.u)
+ * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u)
+ * @P9_DMSOCKET: mode bit for socket (9P2000.u)
+ * @P9_DMSETUID: mode bit for setuid (9P2000.u)
+ * @P9_DMSETGID: mode bit for setgid (9P2000.u)
+ * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u)
+ *
+ * 9P permissions differ slightly from Posix standard modes.
+ *
+ * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
+ */
+enum p9_perm_t {
+	P9_DMDIR = 0x80000000,
+	P9_DMAPPEND = 0x40000000,
+	P9_DMEXCL = 0x20000000,
+	P9_DMMOUNT = 0x10000000,
+	P9_DMAUTH = 0x08000000,
+	P9_DMTMP = 0x04000000,
+/* 9P2000.u extensions */
+	P9_DMSYMLINK = 0x02000000,
+	P9_DMLINK = 0x01000000,
+	P9_DMDEVICE = 0x00800000,
+	P9_DMNAMEDPIPE = 0x00200000,
+	P9_DMSOCKET = 0x00100000,
+	P9_DMSETUID = 0x00080000,
+	P9_DMSETGID = 0x00040000,
+	P9_DMSETVTX = 0x00010000,
+};
+
+/**
+ * enum p9_qid_t - QID types
+ * @P9_QTDIR: directory
+ * @P9_QTAPPEND: append-only
+ * @P9_QTEXCL: excluse use (only one open handle allowed)
+ * @P9_QTMOUNT: mount points
+ * @P9_QTAUTH: authentication file
+ * @P9_QTTMP: non-backed-up files
+ * @P9_QTSYMLINK: symbolic links (9P2000.u)
+ * @P9_QTLINK: hard-link (9P2000.u)
+ * @P9_QTFILE: normal files
+ *
+ * QID types are a subset of permissions - they are primarily
+ * used to differentiate semantics for a file system entity via
+ * a jump-table.  Their value is also the most significant 16 bits
+ * of the permission_t
+ *
+ * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
+ */
+enum p9_qid_t {
+	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,
+};
+
+/* 9P Magic Numbers */
+#define P9_NOTAG	(u16)(~0)
+#define P9_NOFID	(u32)(~0)
+#define P9_MAXWELEM	16
+
+/* ample room for Twrite/Rread header */
+#define P9_IOHDRSZ	24
+
+/* Room for readdir header */
+#define P9_READDIRHDRSZ	24
+
+/**
+ * struct p9_str - length prefixed string type
+ * @len: length of the string
+ * @str: the string
+ *
+ * The protocol uses length prefixed strings for all
+ * string data, so we replicate that for our internal
+ * string members.
+ */
+
+struct p9_str {
+	u16 len;
+	char *str;
+};
+
+/**
+ * struct p9_qid - file system entity information
+ * @type: 8-bit type &p9_qid_t
+ * @version: 16-bit monotonically incrementing version number
+ * @path: 64-bit per-server-unique ID for a file system element
+ *
+ * qids are identifiers used by 9P servers to track file system
+ * entities.  The type is used to differentiate semantics for operations
+ * on the entity (ie. read means something different on a directory than
+ * on a file).  The path provides a server unique index for an entity
+ * (roughly analogous to an inode number), while the version is updated
+ * every time a file is modified and can be used to maintain cache
+ * coherency between clients and serves.
+ * Servers will often differentiate purely synthetic entities by setting
+ * their version to 0, signaling that they should never be cached and
+ * should be accessed synchronously.
+ *
+ * See Also://plan9.bell-labs.com/magic/man2html/2/stat
+ */
+
+struct p9_qid {
+	u8 type;
+	u32 version;
+	u64 path;
+};
+
+/**
+ * struct p9_stat - file system metadata information
+ * @size: length prefix for this stat structure instance
+ * @type: the type of the server (equivalent to a major number)
+ * @dev: the sub-type of the server (equivalent to a minor number)
+ * @qid: unique id from the server of type &p9_qid
+ * @mode: Plan 9 format permissions of type &p9_perm_t
+ * @atime: Last access/read time
+ * @mtime: Last modify/write time
+ * @length: file length
+ * @name: last element of path (aka filename) in type &p9_str
+ * @uid: owner name in type &p9_str
+ * @gid: group owner in type &p9_str
+ * @muid: last modifier in type &p9_str
+ * @extension: area used to encode extended UNIX support in type &p9_str
+ * @n_uid: numeric user id of owner (part of 9p2000.u extension)
+ * @n_gid: numeric group id (part of 9p2000.u extension)
+ * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension)
+ *
+ * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat
+ */
+
+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 */
+};
+
+struct p9_stat_dotl {
+	u64 st_result_mask;
+	struct p9_qid qid;
+	u32 st_mode;
+	u32 st_uid;
+	u32 st_gid;
+	u64 st_nlink;
+	u64 st_rdev;
+	u64 st_size;
+	u64 st_blksize;
+	u64 st_blocks;
+	u64 st_atime_sec;
+	u64 st_atime_nsec;
+	u64 st_mtime_sec;
+	u64 st_mtime_nsec;
+	u64 st_ctime_sec;
+	u64 st_ctime_nsec;
+	u64 st_btime_sec;
+	u64 st_btime_nsec;
+	u64 st_gen;
+	u64 st_data_version;
+};
+
+#define P9_STATS_MODE		0x00000001ULL
+#define P9_STATS_NLINK		0x00000002ULL
+#define P9_STATS_UID		0x00000004ULL
+#define P9_STATS_GID		0x00000008ULL
+#define P9_STATS_RDEV		0x00000010ULL
+#define P9_STATS_ATIME		0x00000020ULL
+#define P9_STATS_MTIME		0x00000040ULL
+#define P9_STATS_CTIME		0x00000080ULL
+#define P9_STATS_INO		0x00000100ULL
+#define P9_STATS_SIZE		0x00000200ULL
+#define P9_STATS_BLOCKS		0x00000400ULL
+
+#define P9_STATS_BTIME		0x00000800ULL
+#define P9_STATS_GEN		0x00001000ULL
+#define P9_STATS_DATA_VERSION	0x00002000ULL
+
+#define P9_STATS_BASIC		0x000007ffULL /* Mask for fields up to BLOCKS */
+#define P9_STATS_ALL		0x00003fffULL /* Mask for All fields above */
+
+/**
+ * struct p9_iattr_dotl - P9 inode attribute for setattr
+ * @valid: bitfield specifying which fields are valid
+ *         same as in struct iattr
+ * @mode: File permission bits
+ * @uid: user id of owner
+ * @gid: group id
+ * @size: File size
+ * @atime_sec: Last access time, seconds
+ * @atime_nsec: Last access time, nanoseconds
+ * @mtime_sec: Last modification time, seconds
+ * @mtime_nsec: Last modification time, nanoseconds
+ */
+
+struct p9_iattr_dotl {
+	u32 valid;
+	u32 mode;
+	u32 uid;
+	u32 gid;
+	u64 size;
+	u64 atime_sec;
+	u64 atime_nsec;
+	u64 mtime_sec;
+	u64 mtime_nsec;
+};
+
+#define P9_LOCK_SUCCESS 0
+#define P9_LOCK_BLOCKED 1
+#define P9_LOCK_ERROR 2
+#define P9_LOCK_GRACE 3
+
+#define P9_LOCK_FLAGS_BLOCK 1
+#define P9_LOCK_FLAGS_RECLAIM 2
+
+/* struct p9_flock: POSIX lock structure
+ * @type - type of lock
+ * @flags - lock flags
+ * @start - starting offset of the lock
+ * @length - number of bytes
+ * @proc_id - process id which wants to take lock
+ * @client_id - client id
+ */
+
+struct p9_flock {
+	u8 type;
+	u32 flags;
+	u64 start;
+	u64 length;
+	u32 proc_id;
+	char *client_id;
+};
+
+/* struct p9_getlock: getlock structure
+ * @type - type of lock
+ * @start - starting offset of the lock
+ * @length - number of bytes
+ * @proc_id - process id which wants to take lock
+ * @client_id - client id
+ */
+
+struct p9_getlock {
+	u8 type;
+	u64 start;
+	u64 length;
+	u32 proc_id;
+	char *client_id;
+};
+
+/* Structures for Protocol Operations */
+struct p9_tstatfs {
+	u32 fid;
+};
+
+struct p9_rstatfs {
+	u32 type;
+	u32 bsize;
+	u64 blocks;
+	u64 bfree;
+	u64 bavail;
+	u64 files;
+	u64 ffree;
+	u64 fsid;
+	u32 namelen;
+};
+
+struct p9_trename {
+	u32 fid;
+	u32 newdirfid;
+	struct p9_str name;
+};
+
+struct p9_rrename {
+};
+
+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;
+	u32 n_uname;		/* 9P2000.u extensions */
+};
+
+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;
+	u32 n_uname;		/* 9P2000.u extensions */
+};
+
+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_treaddir {
+	u32 fid;
+	u64 offset;
+	u32 count;
+};
+
+struct p9_rreaddir {
+	u32 count;
+	u8 *data;
+};
+
+
+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_wstat stat;
+};
+
+struct p9_twstat {
+	u32 fid;
+	struct p9_wstat stat;
+};
+
+struct p9_rwstat {
+};
+
+/**
+ * struct p9_fcall - primary packet structure
+ * @size: prefixed length of the structure
+ * @id: protocol operating identifier of type &p9_msg_t
+ * @tag: transaction id of the request
+ * @offset: used by marshalling routines to track currentposition in buffer
+ * @capacity: used by marshalling routines to track total malloc'd capacity
+ * @pubuf: Payload user buffer given by the caller
+ * @pubuf: Payload kernel buffer given by the caller
+ * @pbuf_size: pubuf/pkbuf(only one will be !NULL) size to be read/write.
+ * @private: For transport layer's use.
+ * @sdata: payload
+ *
+ * &p9_fcall represents the structure for all 9P RPC
+ * transactions.  Requests are packaged into fcalls, and reponses
+ * must be extracted from them.
+ *
+ * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall
+ */
+
+struct p9_fcall {
+	u32 size;
+	u8 id;
+	u16 tag;
+
+	size_t offset;
+	size_t capacity;
+	char __user *pubuf;
+	char *pkbuf;
+	size_t pbuf_size;
+	void *private;
+
+	u8 *sdata;
+};
+
+struct p9_idpool;
+
+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_trans_fd_init(void);
+void p9_trans_fd_exit(void);
+#endif /* NET_9P_H */