lockd.h revision 3a649b884637c4fdff50a6beebc3dc0e6082e048 
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/kref.h>
18#include <linux/utsname.h>
19#include <linux/nfsd/nfsfh.h>
20#include <linux/lockd/bind.h>
21#include <linux/lockd/xdr.h>
22#ifdef CONFIG_LOCKD_V4
23#include <linux/lockd/xdr4.h>
24#endif
25#include <linux/lockd/debug.h>
26
27/*
28 * Version string
29 */
30#define LOCKD_VERSION		"0.5"
31
32/*
33 * Default timeout for RPC calls (seconds)
34 */
35#define LOCKD_DFLT_TIMEO	10
36
37/*
38 * Lockd host handle (used both by the client and server personality).
39 */
40struct nlm_host {
41	struct nlm_host *	h_next;		/* linked list (hash table) */
42	struct sockaddr_in	h_addr;		/* peer address */
43	struct rpc_clnt	*	h_rpcclnt;	/* RPC client to talk to peer */
44	char			h_name[20];	/* remote hostname */
45	u32			h_version;	/* interface version */
46	unsigned short		h_proto;	/* transport proto */
47	unsigned short		h_reclaiming : 1,
48				h_server     : 1, /* server side, not client side */
49				h_inuse      : 1,
50				h_killed     : 1,
51				h_monitored  : 1;
52	wait_queue_head_t	h_gracewait;	/* wait while reclaiming */
53	u32			h_state;	/* pseudo-state counter */
54	u32			h_nsmstate;	/* true remote NSM state */
55	u32			h_pidcount;	/* Pseudopids */
56	atomic_t		h_count;	/* reference count */
57	struct semaphore	h_sema;		/* mutex for pmap binding */
58	unsigned long		h_nextrebind;	/* next portmap call */
59	unsigned long		h_expires;	/* eligible for GC */
60	struct list_head	h_lockowners;	/* Lockowners for the client */
61	spinlock_t		h_lock;
62	struct list_head	h_granted;	/* Locks in GRANTED state */
63	struct list_head	h_reclaim;	/* Locks in RECLAIM state */
64};
65
66/*
67 * Map an fl_owner_t into a unique 32-bit "pid"
68 */
69struct nlm_lockowner {
70	struct list_head list;
71	atomic_t count;
72
73	struct nlm_host *host;
74	fl_owner_t owner;
75	uint32_t pid;
76};
77
78struct nlm_wait;
79
80/*
81 * Memory chunk for NLM client RPC request.
82 */
83#define NLMCLNT_OHSIZE		(sizeof(system_utsname.nodename)+10)
84struct nlm_rqst {
85	unsigned int		a_flags;	/* initial RPC task flags */
86	struct nlm_host *	a_host;		/* host handle */
87	struct nlm_args		a_args;		/* arguments */
88	struct nlm_res		a_res;		/* result */
89	unsigned int		a_retries;	/* Retry count */
90	char			a_owner[NLMCLNT_OHSIZE];
91};
92
93/*
94 * This struct describes a file held open by lockd on behalf of
95 * an NFS client.
96 */
97struct nlm_file {
98	struct nlm_file *	f_next;		/* linked list */
99	struct nfs_fh		f_handle;	/* NFS file handle */
100	struct file *		f_file;		/* VFS file pointer */
101	struct nlm_share *	f_shares;	/* DOS shares */
102	struct nlm_block *	f_blocks;	/* blocked locks */
103	unsigned int		f_locks;	/* guesstimate # of locks */
104	unsigned int		f_count;	/* reference count */
105	struct semaphore	f_sema;		/* avoid concurrent access */
106	int		       	f_hash;		/* hash of f_handle */
107};
108
109/*
110 * This is a server block (i.e. a lock requested by some client which
111 * couldn't be granted because of a conflicting lock).
112 */
113#define NLM_NEVER		(~(unsigned long) 0)
114struct nlm_block {
115	struct kref		b_count;	/* Reference count */
116	struct nlm_block *	b_next;		/* linked list (all blocks) */
117	struct nlm_block *	b_fnext;	/* linked list (per file) */
118	struct nlm_rqst		b_call;		/* RPC args & callback info */
119	struct svc_serv *	b_daemon;	/* NLM service */
120	struct nlm_host *	b_host;		/* host handle for RPC clnt */
121	unsigned long		b_when;		/* next re-xmit */
122	unsigned int		b_id;		/* block id */
123	unsigned char		b_queued;	/* re-queued */
124	unsigned char		b_granted;	/* VFS granted lock */
125	unsigned char		b_done;		/* callback complete */
126	struct nlm_file *	b_file;		/* file in question */
127};
128
129/*
130 * Valid actions for nlmsvc_traverse_files
131 */
132#define NLM_ACT_CHECK		0		/* check for locks */
133#define NLM_ACT_MARK		1		/* mark & sweep */
134#define NLM_ACT_UNLOCK		2		/* release all locks */
135
136/*
137 * Global variables
138 */
139extern struct rpc_program	nlm_program;
140extern struct svc_procedure	nlmsvc_procedures[];
141#ifdef CONFIG_LOCKD_V4
142extern struct svc_procedure	nlmsvc_procedures4[];
143#endif
144extern int			nlmsvc_grace_period;
145extern unsigned long		nlmsvc_timeout;
146
147/*
148 * Lockd client functions
149 */
150struct nlm_rqst * nlmclnt_alloc_call(void);
151struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
152void		  nlmclnt_finish_block(struct nlm_wait *block);
153int		  nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
154u32		  nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *);
155void		  nlmclnt_recovery(struct nlm_host *, u32);
156int		  nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
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(const struct sockaddr_in *sin1, const 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(const struct file_lock *fl1, const 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