lockd.h revision aaaa99423b4b1f9cfd33ea5643d9274c25f62491 
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/config.h>
15#include <linux/in.h>
16#include <linux/fs.h>
17#include <linux/utsname.h>
18#include <linux/nfsd/nfsfh.h>
19#include <linux/lockd/bind.h>
20#include <linux/lockd/xdr.h>
21#ifdef CONFIG_LOCKD_V4
22#include <linux/lockd/xdr4.h>
23#endif
24#include <linux/lockd/debug.h>
25
26/*
27 * Version string
28 */
29#define LOCKD_VERSION		"0.5"
30
31/*
32 * Default timeout for RPC calls (seconds)
33 */
34#define LOCKD_DFLT_TIMEO	10
35
36/*
37 * Lockd host handle (used both by the client and server personality).
38 */
39struct nlm_host {
40	struct nlm_host *	h_next;		/* linked list (hash table) */
41	struct sockaddr_in	h_addr;		/* peer address */
42	struct rpc_clnt	*	h_rpcclnt;	/* RPC client to talk to peer */
43	char			h_name[20];	/* remote hostname */
44	u32			h_version;	/* interface version */
45	unsigned short		h_proto;	/* transport proto */
46	unsigned short		h_reclaiming : 1,
47				h_server     : 1, /* server side, not client side */
48				h_inuse      : 1,
49				h_killed     : 1,
50				h_monitored  : 1;
51	wait_queue_head_t	h_gracewait;	/* wait while reclaiming */
52	u32			h_state;	/* pseudo-state counter */
53	u32			h_nsmstate;	/* true remote NSM state */
54	u32			h_pidcount;	/* Pseudopids */
55	atomic_t		h_count;	/* reference count */
56	struct semaphore	h_sema;		/* mutex for pmap binding */
57	unsigned long		h_nextrebind;	/* next portmap call */
58	unsigned long		h_expires;	/* eligible for GC */
59	struct list_head	h_lockowners;	/* Lockowners for the client */
60	spinlock_t		h_lock;
61};
62
63/*
64 * Map an fl_owner_t into a unique 32-bit "pid"
65 */
66struct nlm_lockowner {
67	struct list_head list;
68	atomic_t count;
69
70	struct nlm_host *host;
71	fl_owner_t owner;
72	uint32_t pid;
73};
74
75struct nlm_wait;
76
77/*
78 * Memory chunk for NLM client RPC request.
79 */
80#define NLMCLNT_OHSIZE		(sizeof(system_utsname.nodename)+10)
81struct nlm_rqst {
82	unsigned int		a_flags;	/* initial RPC task flags */
83	struct nlm_host *	a_host;		/* host handle */
84	struct nlm_args		a_args;		/* arguments */
85	struct nlm_res		a_res;		/* result */
86	struct nlm_wait *	a_block;
87	unsigned int		a_retries;	/* Retry count */
88	char			a_owner[NLMCLNT_OHSIZE];
89};
90
91/*
92 * This struct describes a file held open by lockd on behalf of
93 * an NFS client.
94 */
95struct nlm_file {
96	struct nlm_file *	f_next;		/* linked list */
97	struct nfs_fh		f_handle;	/* NFS file handle */
98	struct file *		f_file;		/* VFS file pointer */
99	struct nlm_share *	f_shares;	/* DOS shares */
100	struct nlm_block *	f_blocks;	/* blocked locks */
101	unsigned int		f_locks;	/* guesstimate # of locks */
102	unsigned int		f_count;	/* reference count */
103	struct semaphore	f_sema;		/* avoid concurrent access */
104	int		       	f_hash;		/* hash of f_handle */
105};
106
107/*
108 * This is a server block (i.e. a lock requested by some client which
109 * couldn't be granted because of a conflicting lock).
110 */
111#define NLM_NEVER		(~(unsigned long) 0)
112struct nlm_block {
113	struct nlm_block *	b_next;		/* linked list (all blocks) */
114	struct nlm_block *	b_fnext;	/* linked list (per file) */
115	struct nlm_rqst		b_call;		/* RPC args & callback info */
116	struct svc_serv *	b_daemon;	/* NLM service */
117	struct nlm_host *	b_host;		/* host handle for RPC clnt */
118	unsigned long		b_when;		/* next re-xmit */
119	unsigned int		b_id;		/* block id */
120	unsigned char		b_queued;	/* re-queued */
121	unsigned char		b_granted;	/* VFS granted lock */
122	unsigned char		b_incall;	/* doing callback */
123	unsigned char		b_done;		/* callback complete */
124	struct nlm_file *	b_file;		/* file in question */
125};
126
127/*
128 * Valid actions for nlmsvc_traverse_files
129 */
130#define NLM_ACT_CHECK		0		/* check for locks */
131#define NLM_ACT_MARK		1		/* mark & sweep */
132#define NLM_ACT_UNLOCK		2		/* release all locks */
133
134/*
135 * Global variables
136 */
137extern struct rpc_program	nlm_program;
138extern struct svc_procedure	nlmsvc_procedures[];
139#ifdef CONFIG_LOCKD_V4
140extern struct svc_procedure	nlmsvc_procedures4[];
141#endif
142extern int			nlmsvc_grace_period;
143extern unsigned long		nlmsvc_timeout;
144
145/*
146 * Lockd client functions
147 */
148struct nlm_rqst * nlmclnt_alloc_call(void);
149int		  nlmclnt_prepare_block(struct nlm_rqst *req, struct nlm_host *host, struct file_lock *fl);
150void		  nlmclnt_finish_block(struct nlm_rqst *req);
151long		  nlmclnt_block(struct nlm_rqst *req, long timeout);
152u32		  nlmclnt_grant(struct nlm_lock *);
153void		  nlmclnt_recovery(struct nlm_host *, u32);
154int		  nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
155int		  nlmclnt_setgrantargs(struct nlm_rqst *, struct nlm_lock *);
156void		  nlmclnt_freegrantargs(struct nlm_rqst *);
157
158/*
159 * Host cache
160 */
161struct nlm_host * nlmclnt_lookup_host(struct sockaddr_in *, int, int);
162struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *);
163struct nlm_host * nlm_lookup_host(int server, struct sockaddr_in *, int, int);
164struct rpc_clnt * nlm_bind_host(struct nlm_host *);
165void		  nlm_rebind_host(struct nlm_host *);
166struct nlm_host * nlm_get_host(struct nlm_host *);
167void		  nlm_release_host(struct nlm_host *);
168void		  nlm_shutdown_hosts(void);
169extern struct nlm_host *nlm_find_client(void);
170
171
172/*
173 * Server-side lock handling
174 */
175int		  nlmsvc_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
176u32		  nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
177					struct nlm_lock *, int, struct nlm_cookie *);
178u32		  nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
179u32		  nlmsvc_testlock(struct nlm_file *, struct nlm_lock *,
180					struct nlm_lock *);
181u32		  nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
182unsigned long	  nlmsvc_retry_blocked(void);
183int		  nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
184					int action);
185void	  nlmsvc_grant_reply(struct svc_rqst *, struct nlm_cookie *, u32);
186
187/*
188 * File handling for the server personality
189 */
190u32		  nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
191					struct nfs_fh *);
192void		  nlm_release_file(struct nlm_file *);
193void		  nlmsvc_mark_resources(void);
194void		  nlmsvc_free_host_resources(struct nlm_host *);
195void		  nlmsvc_invalidate_all(void);
196
197static __inline__ struct inode *
198nlmsvc_file_inode(struct nlm_file *file)
199{
200	return file->f_file->f_dentry->d_inode;
201}
202
203/*
204 * Compare two host addresses (needs modifying for ipv6)
205 */
206static __inline__ int
207nlm_cmp_addr(struct sockaddr_in *sin1, struct sockaddr_in *sin2)
208{
209	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
210}
211
212/*
213 * Compare two NLM locks.
214 * When the second lock is of type F_UNLCK, this acts like a wildcard.
215 */
216static __inline__ int
217nlm_compare_locks(struct file_lock *fl1, struct file_lock *fl2)
218{
219	return	fl1->fl_pid   == fl2->fl_pid
220	     && fl1->fl_start == fl2->fl_start
221	     && fl1->fl_end   == fl2->fl_end
222	     &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
223}
224
225extern struct lock_manager_operations nlmsvc_lock_operations;
226
227#endif /* __KERNEL__ */
228
229#endif /* LINUX_LOCKD_LOCKD_H */
230