xref: /linux/fs/afs/main.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /* main.c: AFS client file system
2  *
3  * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/moduleparam.h>
14 #include <linux/init.h>
15 #include <linux/completion.h>
16 #include <rxrpc/rxrpc.h>
17 #include <rxrpc/transport.h>
18 #include <rxrpc/call.h>
19 #include <rxrpc/peer.h>
20 #include "cache.h"
21 #include "cell.h"
22 #include "server.h"
23 #include "fsclient.h"
24 #include "cmservice.h"
25 #include "kafstimod.h"
26 #include "kafsasyncd.h"
27 #include "internal.h"
28 
29 struct rxrpc_transport *afs_transport;
30 
31 static int afs_adding_peer(struct rxrpc_peer *peer);
32 static void afs_discarding_peer(struct rxrpc_peer *peer);
33 
34 
35 MODULE_DESCRIPTION("AFS Client File System");
36 MODULE_AUTHOR("Red Hat, Inc.");
37 MODULE_LICENSE("GPL");
38 
39 static char *rootcell;
40 
41 module_param(rootcell, charp, 0);
42 MODULE_PARM_DESC(rootcell, "root AFS cell name and VL server IP addr list");
43 
44 
45 static struct rxrpc_peer_ops afs_peer_ops = {
46 	.adding		= afs_adding_peer,
47 	.discarding	= afs_discarding_peer,
48 };
49 
50 struct list_head afs_cb_hash_tbl[AFS_CB_HASH_COUNT];
51 DEFINE_SPINLOCK(afs_cb_hash_lock);
52 
53 #ifdef AFS_CACHING_SUPPORT
54 static struct cachefs_netfs_operations afs_cache_ops = {
55 	.get_page_cookie	= afs_cache_get_page_cookie,
56 };
57 
58 struct cachefs_netfs afs_cache_netfs = {
59 	.name			= "afs",
60 	.version		= 0,
61 	.ops			= &afs_cache_ops,
62 };
63 #endif
64 
65 /*****************************************************************************/
66 /*
67  * initialise the AFS client FS module
68  */
69 static int __init afs_init(void)
70 {
71 	int loop, ret;
72 
73 	printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 registering.\n");
74 
75 	/* initialise the callback hash table */
76 	spin_lock_init(&afs_cb_hash_lock);
77 	for (loop = AFS_CB_HASH_COUNT - 1; loop >= 0; loop--)
78 		INIT_LIST_HEAD(&afs_cb_hash_tbl[loop]);
79 
80 	/* register the /proc stuff */
81 	ret = afs_proc_init();
82 	if (ret < 0)
83 		return ret;
84 
85 #ifdef AFS_CACHING_SUPPORT
86 	/* we want to be able to cache */
87 	ret = cachefs_register_netfs(&afs_cache_netfs,
88 				     &afs_cache_cell_index_def);
89 	if (ret < 0)
90 		goto error;
91 #endif
92 
93 #ifdef CONFIG_KEYS_TURNED_OFF
94 	ret = afs_key_register();
95 	if (ret < 0)
96 		goto error_cache;
97 #endif
98 
99 	/* initialise the cell DB */
100 	ret = afs_cell_init(rootcell);
101 	if (ret < 0)
102 		goto error_keys;
103 
104 	/* start the timeout daemon */
105 	ret = afs_kafstimod_start();
106 	if (ret < 0)
107 		goto error_keys;
108 
109 	/* start the async operation daemon */
110 	ret = afs_kafsasyncd_start();
111 	if (ret < 0)
112 		goto error_kafstimod;
113 
114 	/* create the RxRPC transport */
115 	ret = rxrpc_create_transport(7001, &afs_transport);
116 	if (ret < 0)
117 		goto error_kafsasyncd;
118 
119 	afs_transport->peer_ops = &afs_peer_ops;
120 
121 	/* register the filesystems */
122 	ret = afs_fs_init();
123 	if (ret < 0)
124 		goto error_transport;
125 
126 	return ret;
127 
128  error_transport:
129 	rxrpc_put_transport(afs_transport);
130  error_kafsasyncd:
131 	afs_kafsasyncd_stop();
132  error_kafstimod:
133 	afs_kafstimod_stop();
134  error_keys:
135 #ifdef CONFIG_KEYS_TURNED_OFF
136 	afs_key_unregister();
137  error_cache:
138 #endif
139 #ifdef AFS_CACHING_SUPPORT
140 	cachefs_unregister_netfs(&afs_cache_netfs);
141  error:
142 #endif
143 	afs_cell_purge();
144 	afs_proc_cleanup();
145 	printk(KERN_ERR "kAFS: failed to register: %d\n", ret);
146 	return ret;
147 } /* end afs_init() */
148 
149 /* XXX late_initcall is kludgy, but the only alternative seems to create
150  * a transport upon the first mount, which is worse. Or is it?
151  */
152 late_initcall(afs_init);	/* must be called after net/ to create socket */
153 /*****************************************************************************/
154 /*
155  * clean up on module removal
156  */
157 static void __exit afs_exit(void)
158 {
159 	printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 unregistering.\n");
160 
161 	afs_fs_exit();
162 	rxrpc_put_transport(afs_transport);
163 	afs_kafstimod_stop();
164 	afs_kafsasyncd_stop();
165 	afs_cell_purge();
166 #ifdef CONFIG_KEYS_TURNED_OFF
167 	afs_key_unregister();
168 #endif
169 #ifdef AFS_CACHING_SUPPORT
170 	cachefs_unregister_netfs(&afs_cache_netfs);
171 #endif
172 	afs_proc_cleanup();
173 
174 } /* end afs_exit() */
175 
176 module_exit(afs_exit);
177 
178 /*****************************************************************************/
179 /*
180  * notification that new peer record is being added
181  * - called from krxsecd
182  * - return an error to induce an abort
183  * - mustn't sleep (caller holds an rwlock)
184  */
185 static int afs_adding_peer(struct rxrpc_peer *peer)
186 {
187 	struct afs_server *server;
188 	int ret;
189 
190 	_debug("kAFS: Adding new peer %08x\n", ntohl(peer->addr.s_addr));
191 
192 	/* determine which server the peer resides in (if any) */
193 	ret = afs_server_find_by_peer(peer, &server);
194 	if (ret < 0)
195 		return ret; /* none that we recognise, so abort */
196 
197 	_debug("Server %p{u=%d}\n", server, atomic_read(&server->usage));
198 
199 	_debug("Cell %p{u=%d}\n",
200 	       server->cell, atomic_read(&server->cell->usage));
201 
202 	/* cross-point the structs under a global lock */
203 	spin_lock(&afs_server_peer_lock);
204 	peer->user = server;
205 	server->peer = peer;
206 	spin_unlock(&afs_server_peer_lock);
207 
208 	afs_put_server(server);
209 
210 	return 0;
211 } /* end afs_adding_peer() */
212 
213 /*****************************************************************************/
214 /*
215  * notification that a peer record is being discarded
216  * - called from krxiod or krxsecd
217  */
218 static void afs_discarding_peer(struct rxrpc_peer *peer)
219 {
220 	struct afs_server *server;
221 
222 	_enter("%p",peer);
223 
224 	_debug("Discarding peer %08x (rtt=%lu.%lumS)\n",
225 	       ntohl(peer->addr.s_addr),
226 	       (long) (peer->rtt / 1000),
227 	       (long) (peer->rtt % 1000));
228 
229 	/* uncross-point the structs under a global lock */
230 	spin_lock(&afs_server_peer_lock);
231 	server = peer->user;
232 	if (server) {
233 		peer->user = NULL;
234 		server->peer = NULL;
235 	}
236 	spin_unlock(&afs_server_peer_lock);
237 
238 	_leave("");
239 
240 } /* end afs_discarding_peer() */
241 
242 /*****************************************************************************/
243 /*
244  * clear the dead space between task_struct and kernel stack
245  * - called by supplying -finstrument-functions to gcc
246  */
247 #if 0
248 void __cyg_profile_func_enter (void *this_fn, void *call_site)
249 __attribute__((no_instrument_function));
250 
251 void __cyg_profile_func_enter (void *this_fn, void *call_site)
252 {
253        asm volatile("  movl    %%esp,%%edi     \n"
254                     "  andl    %0,%%edi        \n"
255                     "  addl    %1,%%edi        \n"
256                     "  movl    %%esp,%%ecx     \n"
257                     "  subl    %%edi,%%ecx     \n"
258                     "  shrl    $2,%%ecx        \n"
259                     "  movl    $0xedededed,%%eax     \n"
260                     "  rep stosl               \n"
261                     :
262                     : "i"(~(THREAD_SIZE - 1)), "i"(sizeof(struct thread_info))
263                     : "eax", "ecx", "edi", "memory", "cc"
264                     );
265 }
266 
267 void __cyg_profile_func_exit(void *this_fn, void *call_site)
268 __attribute__((no_instrument_function));
269 
270 void __cyg_profile_func_exit(void *this_fn, void *call_site)
271 {
272        asm volatile("  movl    %%esp,%%edi     \n"
273                     "  andl    %0,%%edi        \n"
274                     "  addl    %1,%%edi        \n"
275                     "  movl    %%esp,%%ecx     \n"
276                     "  subl    %%edi,%%ecx     \n"
277                     "  shrl    $2,%%ecx        \n"
278                     "  movl    $0xdadadada,%%eax     \n"
279                     "  rep stosl               \n"
280                     :
281                     : "i"(~(THREAD_SIZE - 1)), "i"(sizeof(struct thread_info))
282                     : "eax", "ecx", "edi", "memory", "cc"
283                     );
284 }
285 #endif
286