aboutsummaryrefslogtreecommitdiff
path: root/include/linux/lockd/lockd.h
blob: dcaad79f54ed5e74985c165585a354c6d04e0bc0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
/*
 * linux/include/linux/lockd/lockd.h
 *
 * General-purpose lockd include file.
 *
 * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de>
 */

#ifndef LINUX_LOCKD_LOCKD_H
#define LINUX_LOCKD_LOCKD_H

#ifdef __KERNEL__

#include <linux/in.h>
#include <linux/in6.h>
#include <net/ipv6.h>
#include <linux/fs.h>
#include <linux/kref.h>
#include <linux/utsname.h>
#include <linux/nfsd/nfsfh.h>
#include <linux/lockd/bind.h>
#include <linux/lockd/xdr.h>
#ifdef CONFIG_LOCKD_V4
#include <linux/lockd/xdr4.h>
#endif
#include <linux/lockd/debug.h>

/*
 * Version string
 */
#define LOCKD_VERSION		"0.5"

/*
 * Default timeout for RPC calls (seconds)
 */
#define LOCKD_DFLT_TIMEO	10

/*
 * Lockd host handle (used both by the client and server personality).
 */
struct nlm_host {
	struct hlist_node	h_hash;		/* doubly linked list */
	struct sockaddr_storage	h_addr;		/* peer address */
	size_t			h_addrlen;
	struct sockaddr_storage	h_srcaddr;	/* our address (optional) */
	size_t			h_srcaddrlen;
	struct rpc_clnt		*h_rpcclnt;	/* RPC client to talk to peer */
	char			*h_name;		/* remote hostname */
	u32			h_version;	/* interface version */
	unsigned short		h_proto;	/* transport proto */
	unsigned short		h_reclaiming : 1,
				h_server     : 1, /* server side, not client side */
				h_noresvport : 1,
				h_inuse      : 1;
	wait_queue_head_t	h_gracewait;	/* wait while reclaiming */
	struct rw_semaphore	h_rwsem;	/* Reboot recovery lock */
	u32			h_state;	/* pseudo-state counter */
	u32			h_nsmstate;	/* true remote NSM state */
	u32			h_pidcount;	/* Pseudopids */
	atomic_t		h_count;	/* reference count */
	struct mutex		h_mutex;	/* mutex for pmap binding */
	unsigned long		h_nextrebind;	/* next portmap call */
	unsigned long		h_expires;	/* eligible for GC */
	struct list_head	h_lockowners;	/* Lockowners for the client */
	spinlock_t		h_lock;
	struct list_head	h_granted;	/* Locks in GRANTED state */
	struct list_head	h_reclaim;	/* Locks in RECLAIM state */
	struct nsm_handle	*h_nsmhandle;	/* NSM status handle */
	char			*h_addrbuf;	/* address eyecatcher */
	struct net		*net;		/* host net */
};

/*
 * The largest string sm_addrbuf should hold is a full-size IPv6 address
 * (no "::" anywhere) with a scope ID.  The buffer size is computed to
 * hold eight groups of colon-separated four-hex-digit numbers, a
 * percent sign, a scope id (at most 32 bits, in decimal), and NUL.
 */
#define NSM_ADDRBUF		((8 * 4 + 7) + (1 + 10) + 1)

struct nsm_handle {
	struct list_head	sm_link;
	atomic_t		sm_count;
	char			*sm_mon_name;
	char			*sm_name;
	struct sockaddr_storage	sm_addr;
	size_t			sm_addrlen;
	unsigned int		sm_monitored : 1,
				sm_sticky : 1;	/* don't unmonitor */
	struct nsm_private	sm_priv;
	char			sm_addrbuf[NSM_ADDRBUF];
};

/*
 * Rigorous type checking on sockaddr type conversions
 */
static inline struct sockaddr_in *nlm_addr_in(const struct nlm_host *host)
{
	return (struct sockaddr_in *)&host->h_addr;
}

static inline struct sockaddr *nlm_addr(const struct nlm_host *host)
{
	return (struct sockaddr *)&host->h_addr;
}

static inline struct sockaddr_in *nlm_srcaddr_in(const struct nlm_host *host)
{
	return (struct sockaddr_in *)&host->h_srcaddr;
}

static inline struct sockaddr *nlm_srcaddr(const struct nlm_host *host)
{
	return (struct sockaddr *)&host->h_srcaddr;
}

/*
 * Map an fl_owner_t into a unique 32-bit "pid"
 */
struct nlm_lockowner {
	struct list_head list;
	atomic_t count;

	struct nlm_host *host;
	fl_owner_t owner;
	uint32_t pid;
};

struct nlm_wait;

/*
 * Memory chunk for NLM client RPC request.
 */
#define NLMCLNT_OHSIZE		((__NEW_UTS_LEN) + 10u)
struct nlm_rqst {
	atomic_t		a_count;
	unsigned int		a_flags;	/* initial RPC task flags */
	struct nlm_host *	a_host;		/* host handle */
	struct nlm_args		a_args;		/* arguments */
	struct nlm_res		a_res;		/* result */
	struct nlm_block *	a_block;
	unsigned int		a_retries;	/* Retry count */
	u8			a_owner[NLMCLNT_OHSIZE];
};

/*
 * This struct describes a file held open by lockd on behalf of
 * an NFS client.
 */
struct nlm_file {
	struct hlist_node	f_list;		/* linked list */
	struct nfs_fh		f_handle;	/* NFS file handle */
	struct file *		f_file;		/* VFS file pointer */
	struct nlm_share *	f_shares;	/* DOS shares */
	struct list_head	f_blocks;	/* blocked locks */
	unsigned int		f_locks;	/* guesstimate # of locks */
	unsigned int		f_count;	/* reference count */
	struct mutex		f_mutex;	/* avoid concurrent access */
};

/*
 * This is a server block (i.e. a lock requested by some client which
 * couldn't be granted because of a conflicting lock).
 */
#define NLM_NEVER		(~(unsigned long) 0)
/* timeout on non-blocking call: */
#define NLM_TIMEOUT		(7 * HZ)

struct nlm_block {
	struct kref		b_count;	/* Reference count */
	struct list_head	b_list;		/* linked list of all blocks */
	struct list_head	b_flist;	/* linked list (per file) */
	struct nlm_rqst	*	b_call;		/* RPC args & callback info */
	struct svc_serv *	b_daemon;	/* NLM service */
	struct nlm_host *	b_host;		/* host handle for RPC clnt */
	unsigned long		b_when;		/* next re-xmit */
	unsigned int		b_id;		/* block id */
	unsigned char		b_granted;	/* VFS granted lock */
	struct nlm_file *	b_file;		/* file in question */
	struct cache_req *	b_cache_req;	/* deferred request handling */
	struct file_lock *	b_fl;		/* set for GETLK */
	struct cache_deferred_req * b_deferred_req;
	unsigned int		b_flags;	/* block flags */
#define B_QUEUED		1	/* lock queued */
#define B_GOT_CALLBACK		2	/* got lock or conflicting lock */
#define B_TIMED_OUT		4	/* filesystem too slow to respond */
};

/*
 * Global variables
 */
extern const struct rpc_program	nlm_program;
extern struct svc_procedure	nlmsvc_procedures[];
#ifdef CONFIG_LOCKD_V4
extern struct svc_procedure	nlmsvc_procedures4[];
#endif
extern int			nlmsvc_grace_period;
extern unsigned long		nlmsvc_timeout;
extern bool			nsm_use_hostnames;
extern u32			nsm_local_state;

/*
 * Lockd client functions
 */
struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
int		  nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
int		  nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
void		  nlmclnt_release_call(struct nlm_rqst *);
struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
void		  nlmclnt_finish_block(struct nlm_wait *block);
int		  nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
__be32		  nlmclnt_grant(const struct sockaddr *addr,
				const struct nlm_lock *lock);
void		  nlmclnt_recovery(struct nlm_host *);
int		  nlmclnt_reclaim(struct nlm_host *, struct file_lock *,
				  struct nlm_rqst *);
void		  nlmclnt_next_cookie(struct nlm_cookie *);

/*
 * Host cache
 */
struct nlm_host  *nlmclnt_lookup_host(const struct sockaddr *sap,
					const size_t salen,
					const unsigned short protocol,
					const u32 version,
					const char *hostname,
					int noresvport,
					struct net *net);
void		  nlmclnt_release_host(struct nlm_host *);
struct nlm_host  *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
					const char *hostname,
					const size_t hostname_len);
void		  nlmsvc_release_host(struct nlm_host *);
struct rpc_clnt * nlm_bind_host(struct nlm_host *);
void		  nlm_rebind_host(struct nlm_host *);
struct nlm_host * nlm_get_host(struct nlm_host *);
void		  nlm_shutdown_hosts(void);
void		  nlm_shutdown_hosts_net(struct net *net);
void		  nlm_host_rebooted(const struct nlm_reboot *);

/*
 * Host monitoring
 */
int		  nsm_monitor(const struct nlm_host *host);
void		  nsm_unmonitor(const struct nlm_host *host);

struct nsm_handle *nsm_get_handle(const struct sockaddr *sap,
					const size_t salen,
					const char *hostname,
					const size_t hostname_len);
struct nsm_handle *nsm_reboot_lookup(const struct nlm_reboot *info);
void		  nsm_release(struct nsm_handle *nsm);

/*
 * This is used in garbage collection and resource reclaim
 * A return value != 0 means destroy the lock/block/share
 */
typedef int	  (*nlm_host_match_fn_t)(void *cur, struct nlm_host *ref);

/*
 * Server-side lock handling
 */
__be32		  nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
			      struct nlm_host *, struct nlm_lock *, int,
			      struct nlm_cookie *, int);
__be32		  nlmsvc_unlock(struct net *net, struct nlm_file *, struct nlm_lock *);
__be32		  nlmsvc_testlock(struct svc_rqst *, struct nlm_file *,
			struct nlm_host *, struct nlm_lock *,
			struct nlm_lock *, struct nlm_cookie *);
__be32		  nlmsvc_cancel_blocked(struct net *net, struct nlm_file *, struct nlm_lock *);
unsigned long	  nlmsvc_retry_blocked(void);
void		  nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
					nlm_host_match_fn_t match);
void		  nlmsvc_grant_reply(struct nlm_cookie *, __be32);
void		  nlmsvc_release_call(struct nlm_rqst *);

/*
 * File handling for the server personality
 */
__be32		  nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
					struct nfs_fh *);
void		  nlm_release_file(struct nlm_file *);
void		  nlmsvc_mark_resources(struct net *);
void		  nlmsvc_free_host_resources(struct nlm_host *);
void		  nlmsvc_invalidate_all(void);

/*
 * Cluster failover support
 */
int           nlmsvc_unlock_all_by_sb(struct super_block *sb);
int           nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr);

static inline struct inode *nlmsvc_file_inode(struct nlm_file *file)
{
	return file_inode(file->f_file);
}

static inline int __nlm_privileged_request4(const struct sockaddr *sap)
{
	const struct sockaddr_in *sin = (struct sockaddr_in *)sap;

	if (ntohs(sin->sin_port) > 1023)
		return 0;

	return ipv4_is_loopback(sin->sin_addr.s_addr);
}

#if IS_ENABLED(CONFIG_IPV6)
static inline int __nlm_privileged_request6(const struct sockaddr *sap)
{
	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;

	if (ntohs(sin6->sin6_port) > 1023)
		return 0;

	if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_MAPPED)
		return ipv4_is_loopback(sin6->sin6_addr.s6_addr32[3]);

	return ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK;
}
#else	/* IS_ENABLED(CONFIG_IPV6) */
static inline int __nlm_privileged_request6(const struct sockaddr *sap)
{
	return 0;
}
#endif	/* IS_ENABLED(CONFIG_IPV6) */

/*
 * Ensure incoming requests are from local privileged callers.
 *
 * Return TRUE if sender is local and is connecting via a privileged port;
 * otherwise return FALSE.
 */
static inline int nlm_privileged_requester(const struct svc_rqst *rqstp)
{
	const struct sockaddr *sap = svc_addr(rqstp);

	switch (sap->sa_family) {
	case AF_INET:
		return __nlm_privileged_request4(sap);
	case AF_INET6:
		return __nlm_privileged_request6(sap);
	default:
		return 0;
	}
}

/*
 * Compare two NLM locks.
 * When the second lock is of type F_UNLCK, this acts like a wildcard.
 */
static inline int nlm_compare_locks(const struct file_lock *fl1,
				    const struct file_lock *fl2)
{
	return	fl1->fl_pid   == fl2->fl_pid
	     && fl1->fl_owner == fl2->fl_owner
	     && fl1->fl_start == fl2->fl_start
	     && fl1->fl_end   == fl2->fl_end
	     &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
}

extern const struct lock_manager_operations nlmsvc_lock_operations;

#endif /* __KERNEL__ */

#endif /* LINUX_LOCKD_LOCKD_H */