WSL2-Linux-Kernel/fs/9p/v9fs.c

335 строки
7.0 KiB
C

/*
* linux/fs/9p/v9fs.c
*
* This file contains functions assisting in mapping VFS to 9P2000
*
* 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
*
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/parser.h>
#include <linux/idr.h>
#include <net/9p/9p.h>
#include <net/9p/transport.h>
#include <net/9p/conn.h>
#include <net/9p/client.h>
#include "v9fs.h"
#include "v9fs_vfs.h"
/*
* Option Parsing (code inspired by NFS code)
*
*/
enum {
/* Options that take integer arguments */
Opt_debug, Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid,
Opt_rfdno, Opt_wfdno,
/* String options */
Opt_uname, Opt_remotename,
/* Options that take no arguments */
Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd, Opt_pci,
/* Cache options */
Opt_cache_loose,
/* Error token */
Opt_err
};
static match_table_t tokens = {
{Opt_debug, "debug=%x"},
{Opt_port, "port=%u"},
{Opt_msize, "msize=%u"},
{Opt_uid, "uid=%u"},
{Opt_gid, "gid=%u"},
{Opt_afid, "afid=%u"},
{Opt_rfdno, "rfdno=%u"},
{Opt_wfdno, "wfdno=%u"},
{Opt_uname, "uname=%s"},
{Opt_remotename, "aname=%s"},
{Opt_unix, "proto=unix"},
{Opt_tcp, "proto=tcp"},
{Opt_fd, "proto=fd"},
#ifdef CONFIG_PCI_9P
{Opt_pci, "proto=pci"},
#endif
{Opt_tcp, "tcp"},
{Opt_unix, "unix"},
{Opt_fd, "fd"},
{Opt_legacy, "noextend"},
{Opt_nodevmap, "nodevmap"},
{Opt_cache_loose, "cache=loose"},
{Opt_cache_loose, "loose"},
{Opt_err, NULL}
};
extern struct p9_transport *p9pci_trans_create(void);
/*
* Parse option string.
*/
/**
* v9fs_parse_options - parse mount options into session structure
* @options: options string passed from mount
* @v9ses: existing v9fs session information
*
*/
static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
{
char *p;
substring_t args[MAX_OPT_ARGS];
int option;
int ret;
/* setup defaults */
v9ses->port = V9FS_PORT;
v9ses->maxdata = 9000;
v9ses->proto = PROTO_TCP;
v9ses->extended = 1;
v9ses->afid = ~0;
v9ses->debug = 0;
v9ses->rfdno = ~0;
v9ses->wfdno = ~0;
v9ses->cache = 0;
if (!options)
return;
while ((p = strsep(&options, ",")) != NULL) {
int token;
if (!*p)
continue;
token = match_token(p, tokens, args);
if (token < Opt_uname) {
if ((ret = match_int(&args[0], &option)) < 0) {
P9_DPRINTK(P9_DEBUG_ERROR,
"integer field, but no integer?\n");
continue;
}
}
switch (token) {
case Opt_debug:
v9ses->debug = option;
#ifdef CONFIG_NET_9P_DEBUG
p9_debug_level = option;
#endif
break;
case Opt_port:
v9ses->port = option;
break;
case Opt_msize:
v9ses->maxdata = option;
break;
case Opt_uid:
v9ses->uid = option;
break;
case Opt_gid:
v9ses->gid = option;
break;
case Opt_afid:
v9ses->afid = option;
break;
case Opt_rfdno:
v9ses->rfdno = option;
break;
case Opt_wfdno:
v9ses->wfdno = option;
break;
case Opt_tcp:
v9ses->proto = PROTO_TCP;
break;
case Opt_unix:
v9ses->proto = PROTO_UNIX;
break;
case Opt_pci:
v9ses->proto = PROTO_PCI;
break;
case Opt_fd:
v9ses->proto = PROTO_FD;
break;
case Opt_uname:
match_strcpy(v9ses->name, &args[0]);
break;
case Opt_remotename:
match_strcpy(v9ses->remotename, &args[0]);
break;
case Opt_legacy:
v9ses->extended = 0;
break;
case Opt_nodevmap:
v9ses->nodev = 1;
break;
case Opt_cache_loose:
v9ses->cache = CACHE_LOOSE;
break;
default:
continue;
}
}
}
/**
* v9fs_session_init - initialize session
* @v9ses: session information structure
* @dev_name: device being mounted
* @data: options
*
*/
struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
const char *dev_name, char *data)
{
int retval = -EINVAL;
struct p9_transport *trans;
struct p9_fid *fid;
v9ses->name = __getname();
if (!v9ses->name)
return ERR_PTR(-ENOMEM);
v9ses->remotename = __getname();
if (!v9ses->remotename) {
__putname(v9ses->name);
return ERR_PTR(-ENOMEM);
}
strcpy(v9ses->name, V9FS_DEFUSER);
strcpy(v9ses->remotename, V9FS_DEFANAME);
v9fs_parse_options(data, v9ses);
switch (v9ses->proto) {
case PROTO_TCP:
trans = p9_trans_create_tcp(dev_name, v9ses->port);
break;
case PROTO_UNIX:
trans = p9_trans_create_unix(dev_name);
*v9ses->remotename = 0;
break;
case PROTO_FD:
trans = p9_trans_create_fd(v9ses->rfdno, v9ses->wfdno);
*v9ses->remotename = 0;
break;
#ifdef CONFIG_PCI_9P
case PROTO_PCI:
trans = p9pci_trans_create();
*v9ses->remotename = 0;
break;
#endif
default:
printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
retval = -ENOPROTOOPT;
goto error;
};
if (IS_ERR(trans)) {
retval = PTR_ERR(trans);
trans = NULL;
goto error;
}
v9ses->clnt = p9_client_create(trans, v9ses->maxdata + P9_IOHDRSZ,
v9ses->extended);
if (IS_ERR(v9ses->clnt)) {
retval = PTR_ERR(v9ses->clnt);
v9ses->clnt = NULL;
P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
goto error;
}
fid = p9_client_attach(v9ses->clnt, NULL, v9ses->name,
v9ses->remotename);
if (IS_ERR(fid)) {
retval = PTR_ERR(fid);
fid = NULL;
P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
goto error;
}
return fid;
error:
v9fs_session_close(v9ses);
return ERR_PTR(retval);
}
/**
* v9fs_session_close - shutdown a session
* @v9ses: session information structure
*
*/
void v9fs_session_close(struct v9fs_session_info *v9ses)
{
if (v9ses->clnt) {
p9_client_destroy(v9ses->clnt);
v9ses->clnt = NULL;
}
__putname(v9ses->name);
__putname(v9ses->remotename);
}
/**
* v9fs_session_cancel - mark transport as disconnected
* and cancel all pending requests.
*/
void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
p9_client_disconnect(v9ses->clnt);
}
extern int v9fs_error_init(void);
/**
* v9fs_init - Initialize module
*
*/
static int __init init_v9fs(void)
{
printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
return register_filesystem(&v9fs_fs_type);
}
/**
* v9fs_init - shutdown module
*
*/
static void __exit exit_v9fs(void)
{
unregister_filesystem(&v9fs_fs_type);
}
module_init(init_v9fs)
module_exit(exit_v9fs)
MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
MODULE_LICENSE("GPL");