1 /*
2 * linux/include/linux/lockd/lockd.h
3 *
4 * General-purpose lockd include file.
5 *
6 * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de>
7 */
8
9 #ifndef LINUX_LOCKD_LOCKD_H
10 #define LINUX_LOCKD_LOCKD_H
11
12 #ifdef __KERNEL__
13
14 #include <linux/in.h>
15 #include <linux/in6.h>
16 #include <net/ipv6.h>
17 #include <linux/fs.h>
18 #include <linux/kref.h>
19 #include <linux/utsname.h>
20 #include <linux/nfsd/nfsfh.h>
21 #include <linux/lockd/bind.h>
22 #include <linux/lockd/xdr.h>
23 #ifdef CONFIG_LOCKD_V4
24 #include <linux/lockd/xdr4.h>
25 #endif
26 #include <linux/lockd/debug.h>
27
28 /*
29 * Version string
30 */
31 #define LOCKD_VERSION "0.5"
32
33 /*
34 * Default timeout for RPC calls (seconds)
35 */
36 #define LOCKD_DFLT_TIMEO 10
37
38 /*
39 * Lockd host handle (used both by the client and server personality).
40 */
41 struct nlm_host {
42 struct hlist_node h_hash; /* doubly linked list */
43 struct sockaddr_storage h_addr; /* peer address */
44 size_t h_addrlen;
45 struct sockaddr_storage h_srcaddr; /* our address (optional) */
46 size_t h_srcaddrlen;
47 struct rpc_clnt *h_rpcclnt; /* RPC client to talk to peer */
48 char *h_name; /* remote hostname */
49 u32 h_version; /* interface version */
50 unsigned short h_proto; /* transport proto */
51 unsigned short h_reclaiming : 1,
52 h_server : 1, /* server side, not client side */
53 h_noresvport : 1,
54 h_inuse : 1;
55 wait_queue_head_t h_gracewait; /* wait while reclaiming */
56 struct rw_semaphore h_rwsem; /* Reboot recovery lock */
57 u32 h_state; /* pseudo-state counter */
58 u32 h_nsmstate; /* true remote NSM state */
59 u32 h_pidcount; /* Pseudopids */
60 atomic_t h_count; /* reference count */
61 struct mutex h_mutex; /* mutex for pmap binding */
62 unsigned long h_nextrebind; /* next portmap call */
63 unsigned long h_expires; /* eligible for GC */
64 struct list_head h_lockowners; /* Lockowners for the client */
65 spinlock_t h_lock;
66 struct list_head h_granted; /* Locks in GRANTED state */
67 struct list_head h_reclaim; /* Locks in RECLAIM state */
68 struct nsm_handle *h_nsmhandle; /* NSM status handle */
69 char *h_addrbuf; /* address eyecatcher */
70 };
71
72 /*
73 * The largest string sm_addrbuf should hold is a full-size IPv6 address
74 * (no "::" anywhere) with a scope ID. The buffer size is computed to
75 * hold eight groups of colon-separated four-hex-digit numbers, a
76 * percent sign, a scope id (at most 32 bits, in decimal), and NUL.
77 */
78 #define NSM_ADDRBUF ((8 * 4 + 7) + (1 + 10) + 1)
79
80 struct nsm_handle {
81 struct list_head sm_link;
82 atomic_t sm_count;
83 char *sm_mon_name;
84 char *sm_name;
85 struct sockaddr_storage sm_addr;
86 size_t sm_addrlen;
87 unsigned int sm_monitored : 1,
88 sm_sticky : 1; /* don't unmonitor */
89 struct nsm_private sm_priv;
90 char sm_addrbuf[NSM_ADDRBUF];
91 };
92
93 /*
94 * Rigorous type checking on sockaddr type conversions
95 */
nlm_addr_in(const struct nlm_host * host)96 static inline struct sockaddr_in *nlm_addr_in(const struct nlm_host *host)
97 {
98 return (struct sockaddr_in *)&host->h_addr;
99 }
100
nlm_addr(const struct nlm_host * host)101 static inline struct sockaddr *nlm_addr(const struct nlm_host *host)
102 {
103 return (struct sockaddr *)&host->h_addr;
104 }
105
nlm_srcaddr_in(const struct nlm_host * host)106 static inline struct sockaddr_in *nlm_srcaddr_in(const struct nlm_host *host)
107 {
108 return (struct sockaddr_in *)&host->h_srcaddr;
109 }
110
nlm_srcaddr(const struct nlm_host * host)111 static inline struct sockaddr *nlm_srcaddr(const struct nlm_host *host)
112 {
113 return (struct sockaddr *)&host->h_srcaddr;
114 }
115
116 /*
117 * Map an fl_owner_t into a unique 32-bit "pid"
118 */
119 struct nlm_lockowner {
120 struct list_head list;
121 atomic_t count;
122
123 struct nlm_host *host;
124 fl_owner_t owner;
125 uint32_t pid;
126 };
127
128 struct nlm_wait;
129
130 /*
131 * Memory chunk for NLM client RPC request.
132 */
133 #define NLMCLNT_OHSIZE ((__NEW_UTS_LEN) + 10u)
134 struct nlm_rqst {
135 atomic_t a_count;
136 unsigned int a_flags; /* initial RPC task flags */
137 struct nlm_host * a_host; /* host handle */
138 struct nlm_args a_args; /* arguments */
139 struct nlm_res a_res; /* result */
140 struct nlm_block * a_block;
141 unsigned int a_retries; /* Retry count */
142 u8 a_owner[NLMCLNT_OHSIZE];
143 };
144
145 /*
146 * This struct describes a file held open by lockd on behalf of
147 * an NFS client.
148 */
149 struct nlm_file {
150 struct hlist_node f_list; /* linked list */
151 struct nfs_fh f_handle; /* NFS file handle */
152 struct file * f_file; /* VFS file pointer */
153 struct nlm_share * f_shares; /* DOS shares */
154 struct list_head f_blocks; /* blocked locks */
155 unsigned int f_locks; /* guesstimate # of locks */
156 unsigned int f_count; /* reference count */
157 struct mutex f_mutex; /* avoid concurrent access */
158 };
159
160 /*
161 * This is a server block (i.e. a lock requested by some client which
162 * couldn't be granted because of a conflicting lock).
163 */
164 #define NLM_NEVER (~(unsigned long) 0)
165 /* timeout on non-blocking call: */
166 #define NLM_TIMEOUT (7 * HZ)
167
168 struct nlm_block {
169 struct kref b_count; /* Reference count */
170 struct list_head b_list; /* linked list of all blocks */
171 struct list_head b_flist; /* linked list (per file) */
172 struct nlm_rqst * b_call; /* RPC args & callback info */
173 struct svc_serv * b_daemon; /* NLM service */
174 struct nlm_host * b_host; /* host handle for RPC clnt */
175 unsigned long b_when; /* next re-xmit */
176 unsigned int b_id; /* block id */
177 unsigned char b_granted; /* VFS granted lock */
178 struct nlm_file * b_file; /* file in question */
179 struct cache_req * b_cache_req; /* deferred request handling */
180 struct file_lock * b_fl; /* set for GETLK */
181 struct cache_deferred_req * b_deferred_req;
182 unsigned int b_flags; /* block flags */
183 #define B_QUEUED 1 /* lock queued */
184 #define B_GOT_CALLBACK 2 /* got lock or conflicting lock */
185 #define B_TIMED_OUT 4 /* filesystem too slow to respond */
186 };
187
188 /*
189 * Global variables
190 */
191 extern struct rpc_program nlm_program;
192 extern struct svc_procedure nlmsvc_procedures[];
193 #ifdef CONFIG_LOCKD_V4
194 extern struct svc_procedure nlmsvc_procedures4[];
195 #endif
196 extern int nlmsvc_grace_period;
197 extern unsigned long nlmsvc_timeout;
198 extern int nsm_use_hostnames;
199 extern u32 nsm_local_state;
200
201 /*
202 * Lockd client functions
203 */
204 struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
205 int nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
206 int nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
207 void nlmclnt_release_call(struct nlm_rqst *);
208 struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
209 void nlmclnt_finish_block(struct nlm_wait *block);
210 int nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
211 __be32 nlmclnt_grant(const struct sockaddr *addr,
212 const struct nlm_lock *lock);
213 void nlmclnt_recovery(struct nlm_host *);
214 int nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
215 void nlmclnt_next_cookie(struct nlm_cookie *);
216
217 /*
218 * Host cache
219 */
220 struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap,
221 const size_t salen,
222 const unsigned short protocol,
223 const u32 version,
224 const char *hostname,
225 int noresvport);
226 void nlmclnt_release_host(struct nlm_host *);
227 struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
228 const char *hostname,
229 const size_t hostname_len);
230 void nlmsvc_release_host(struct nlm_host *);
231 struct rpc_clnt * nlm_bind_host(struct nlm_host *);
232 void nlm_rebind_host(struct nlm_host *);
233 struct nlm_host * nlm_get_host(struct nlm_host *);
234 void nlm_shutdown_hosts(void);
235 void nlm_host_rebooted(const struct nlm_reboot *);
236
237 /*
238 * Host monitoring
239 */
240 int nsm_monitor(const struct nlm_host *host);
241 void nsm_unmonitor(const struct nlm_host *host);
242
243 struct nsm_handle *nsm_get_handle(const struct sockaddr *sap,
244 const size_t salen,
245 const char *hostname,
246 const size_t hostname_len);
247 struct nsm_handle *nsm_reboot_lookup(const struct nlm_reboot *info);
248 void nsm_release(struct nsm_handle *nsm);
249
250 /*
251 * This is used in garbage collection and resource reclaim
252 * A return value != 0 means destroy the lock/block/share
253 */
254 typedef int (*nlm_host_match_fn_t)(void *cur, struct nlm_host *ref);
255
256 /*
257 * Server-side lock handling
258 */
259 __be32 nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
260 struct nlm_host *, struct nlm_lock *, int,
261 struct nlm_cookie *, int);
262 __be32 nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
263 __be32 nlmsvc_testlock(struct svc_rqst *, struct nlm_file *,
264 struct nlm_host *, struct nlm_lock *,
265 struct nlm_lock *, struct nlm_cookie *);
266 __be32 nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
267 unsigned long nlmsvc_retry_blocked(void);
268 void nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
269 nlm_host_match_fn_t match);
270 void nlmsvc_grant_reply(struct nlm_cookie *, __be32);
271 void nlmsvc_release_call(struct nlm_rqst *);
272
273 /*
274 * File handling for the server personality
275 */
276 __be32 nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
277 struct nfs_fh *);
278 void nlm_release_file(struct nlm_file *);
279 void nlmsvc_mark_resources(void);
280 void nlmsvc_free_host_resources(struct nlm_host *);
281 void nlmsvc_invalidate_all(void);
282
283 /*
284 * Cluster failover support
285 */
286 int nlmsvc_unlock_all_by_sb(struct super_block *sb);
287 int nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr);
288
nlmsvc_file_inode(struct nlm_file * file)289 static inline struct inode *nlmsvc_file_inode(struct nlm_file *file)
290 {
291 return file->f_file->f_path.dentry->d_inode;
292 }
293
__nlm_privileged_request4(const struct sockaddr * sap)294 static inline int __nlm_privileged_request4(const struct sockaddr *sap)
295 {
296 const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
297
298 if (ntohs(sin->sin_port) > 1023)
299 return 0;
300
301 return ipv4_is_loopback(sin->sin_addr.s_addr);
302 }
303
304 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
__nlm_privileged_request6(const struct sockaddr * sap)305 static inline int __nlm_privileged_request6(const struct sockaddr *sap)
306 {
307 const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
308
309 if (ntohs(sin6->sin6_port) > 1023)
310 return 0;
311
312 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_MAPPED)
313 return ipv4_is_loopback(sin6->sin6_addr.s6_addr32[3]);
314
315 return ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK;
316 }
317 #else /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
__nlm_privileged_request6(const struct sockaddr * sap)318 static inline int __nlm_privileged_request6(const struct sockaddr *sap)
319 {
320 return 0;
321 }
322 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
323
324 /*
325 * Ensure incoming requests are from local privileged callers.
326 *
327 * Return TRUE if sender is local and is connecting via a privileged port;
328 * otherwise return FALSE.
329 */
nlm_privileged_requester(const struct svc_rqst * rqstp)330 static inline int nlm_privileged_requester(const struct svc_rqst *rqstp)
331 {
332 const struct sockaddr *sap = svc_addr(rqstp);
333
334 switch (sap->sa_family) {
335 case AF_INET:
336 return __nlm_privileged_request4(sap);
337 case AF_INET6:
338 return __nlm_privileged_request6(sap);
339 default:
340 return 0;
341 }
342 }
343
344 /*
345 * Compare two NLM locks.
346 * When the second lock is of type F_UNLCK, this acts like a wildcard.
347 */
nlm_compare_locks(const struct file_lock * fl1,const struct file_lock * fl2)348 static inline int nlm_compare_locks(const struct file_lock *fl1,
349 const struct file_lock *fl2)
350 {
351 return fl1->fl_pid == fl2->fl_pid
352 && fl1->fl_owner == fl2->fl_owner
353 && fl1->fl_start == fl2->fl_start
354 && fl1->fl_end == fl2->fl_end
355 &&(fl1->fl_type == fl2->fl_type || fl2->fl_type == F_UNLCK);
356 }
357
358 extern const struct lock_manager_operations nlmsvc_lock_operations;
359
360 #endif /* __KERNEL__ */
361
362 #endif /* LINUX_LOCKD_LOCKD_H */
363