1 /* 2 * net/9p/9p.c 3 * 4 * 9P entry point 5 * 6 * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net> 7 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> 8 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 12 * as published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to: 21 * Free Software Foundation 22 * 51 Franklin Street, Fifth Floor 23 * Boston, MA 02111-1301 USA 24 * 25 */ 26 27 #include <linux/module.h> 28 #include <linux/moduleparam.h> 29 #include <net/9p/9p.h> 30 #include <linux/fs.h> 31 #include <linux/parser.h> 32 #include <net/9p/transport.h> 33 #include <linux/list.h> 34 #include <linux/spinlock.h> 35 36 #ifdef CONFIG_NET_9P_DEBUG 37 unsigned int p9_debug_level = 0; /* feature-rific global debug level */ 38 EXPORT_SYMBOL(p9_debug_level); 39 module_param_named(debug, p9_debug_level, uint, 0); 40 MODULE_PARM_DESC(debug, "9P debugging level"); 41 #endif 42 43 /* 44 * Dynamic Transport Registration Routines 45 * 46 */ 47 48 static DEFINE_SPINLOCK(v9fs_trans_lock); 49 static LIST_HEAD(v9fs_trans_list); 50 51 /** 52 * v9fs_register_trans - register a new transport with 9p 53 * @m: structure describing the transport module and entry points 54 * 55 */ 56 void v9fs_register_trans(struct p9_trans_module *m) 57 { 58 spin_lock(&v9fs_trans_lock); 59 list_add_tail(&m->list, &v9fs_trans_list); 60 spin_unlock(&v9fs_trans_lock); 61 } 62 EXPORT_SYMBOL(v9fs_register_trans); 63 64 /** 65 * v9fs_unregister_trans - unregister a 9p transport 66 * @m: the transport to remove 67 * 68 */ 69 void v9fs_unregister_trans(struct p9_trans_module *m) 70 { 71 spin_lock(&v9fs_trans_lock); 72 list_del_init(&m->list); 73 spin_unlock(&v9fs_trans_lock); 74 } 75 EXPORT_SYMBOL(v9fs_unregister_trans); 76 77 /** 78 * v9fs_get_trans_by_name - get transport with the matching name 79 * @name: string identifying transport 80 * 81 */ 82 struct p9_trans_module *v9fs_get_trans_by_name(const substring_t *name) 83 { 84 struct p9_trans_module *t, *found = NULL; 85 86 spin_lock(&v9fs_trans_lock); 87 88 list_for_each_entry(t, &v9fs_trans_list, list) 89 if (strncmp(t->name, name->from, name->to-name->from) == 0 && 90 try_module_get(t->owner)) { 91 found = t; 92 break; 93 } 94 95 spin_unlock(&v9fs_trans_lock); 96 return found; 97 } 98 EXPORT_SYMBOL(v9fs_get_trans_by_name); 99 100 /** 101 * v9fs_get_default_trans - get the default transport 102 * 103 */ 104 105 struct p9_trans_module *v9fs_get_default_trans(void) 106 { 107 struct p9_trans_module *t, *found = NULL; 108 109 spin_lock(&v9fs_trans_lock); 110 111 list_for_each_entry(t, &v9fs_trans_list, list) 112 if (t->def && try_module_get(t->owner)) { 113 found = t; 114 break; 115 } 116 117 if (!found) 118 list_for_each_entry(t, &v9fs_trans_list, list) 119 if (try_module_get(t->owner)) { 120 found = t; 121 break; 122 } 123 124 spin_unlock(&v9fs_trans_lock); 125 return found; 126 } 127 EXPORT_SYMBOL(v9fs_get_default_trans); 128 129 /** 130 * v9fs_put_trans - put trans 131 * @m: transport to put 132 * 133 */ 134 void v9fs_put_trans(struct p9_trans_module *m) 135 { 136 if (m) 137 module_put(m->owner); 138 } 139 140 /** 141 * v9fs_init - Initialize module 142 * 143 */ 144 static int __init init_p9(void) 145 { 146 int ret = 0; 147 148 p9_error_init(); 149 printk(KERN_INFO "Installing 9P2000 support\n"); 150 p9_trans_fd_init(); 151 152 return ret; 153 } 154 155 /** 156 * v9fs_init - shutdown module 157 * 158 */ 159 160 static void __exit exit_p9(void) 161 { 162 printk(KERN_INFO "Unloading 9P2000 support\n"); 163 164 p9_trans_fd_exit(); 165 } 166 167 module_init(init_p9) 168 module_exit(exit_p9) 169 170 MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>"); 171 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>"); 172 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>"); 173 MODULE_LICENSE("GPL"); 174