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		"0.4"
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 svc_client *	h_exportent;	/* NFS client */
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_authflavor;	/* RPC authentication type */
48	unsigned short		h_reclaiming : 1,
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	unsigned int		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};
60
61/*
62 * Memory chunk for NLM client RPC request.
63 */
64#define NLMCLNT_OHSIZE		(sizeof(system_utsname.nodename)+10)
65struct nlm_rqst {
66	unsigned int		a_flags;	/* initial RPC task flags */
67	struct nlm_host *	a_host;		/* host handle */
68	struct nlm_args		a_args;		/* arguments */
69	struct nlm_res		a_res;		/* result */
70	char			a_owner[NLMCLNT_OHSIZE];
71};
72
73/*
74 * This struct describes a file held open by lockd on behalf of
75 * an NFS client.
76 */
77struct nlm_file {
78	struct nlm_file *	f_next;		/* linked list */
79	struct nfs_fh		f_handle;	/* NFS file handle */
80	struct file		f_file;		/* VFS file pointer */
81	struct nlm_share *	f_shares;	/* DOS shares */
82	struct nlm_block *	f_blocks;	/* blocked locks */
83	unsigned int		f_locks;	/* guesstimate # of locks */
84	unsigned int		f_count;	/* reference count */
85	struct semaphore	f_sema;		/* avoid concurrent access */
86	int		       	f_hash;		/* hash of f_handle */
87};
88
89/*
90 * This is a server block (i.e. a lock requested by some client which
91 * couldn't be granted because of a conflicting lock).
92 */
93#define NLM_NEVER		(~(unsigned long) 0)
94struct nlm_block {
95	struct nlm_block *	b_next;		/* linked list (all blocks) */
96	struct nlm_block *	b_fnext;	/* linked list (per file) */
97	struct nlm_rqst		b_call;		/* RPC args & callback info */
98	struct svc_serv *	b_daemon;	/* NLM service */
99	struct nlm_host *	b_host;		/* host handle for RPC clnt */
100	unsigned long		b_when;		/* next re-xmit */
101	unsigned int		b_id;		/* block id */
102	unsigned char		b_queued;	/* re-queued */
103	unsigned char		b_granted;	/* VFS granted lock */
104	unsigned char		b_incall;	/* doing callback */
105	unsigned char		b_done;		/* callback complete */
106	struct nlm_file *	b_file;		/* file in question */
107};
108
109/*
110 * Valid actions for nlmsvc_traverse_files
111 */
112#define NLM_ACT_CHECK		0		/* check for locks */
113#define NLM_ACT_MARK		1		/* mark & sweep */
114#define NLM_ACT_UNLOCK		2		/* release all locks */
115
116/*
117 * Global variables
118 */
119extern struct rpc_program	nlm_program;
120extern struct svc_procedure	nlmsvc_procedures[];
121#ifdef CONFIG_LOCKD_V4
122extern struct svc_procedure	nlmsvc_procedures4[];
123#endif
124extern int			nlmsvc_grace_period;
125extern unsigned long		nlmsvc_timeout;
126
127/*
128 * Lockd client functions
129 */
130struct nlm_rqst * nlmclnt_alloc_call(void);
131int		  nlmclnt_call(struct nlm_rqst *, u32);
132int		  nlmclnt_async_call(struct nlm_rqst *, u32, rpc_action);
133int		  nlmclnt_block(struct nlm_host *, struct file_lock *, u32 *);
134int		  nlmclnt_cancel(struct nlm_host *, struct file_lock *);
135u32		  nlmclnt_grant(struct nlm_lock *);
136void		  nlmclnt_recovery(struct nlm_host *, u32);
137int		  nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
138int		  nlmclnt_setgrantargs(struct nlm_rqst *, struct nlm_lock *);
139void		  nlmclnt_freegrantargs(struct nlm_rqst *);
140
141/*
142 * Host cache
143 */
144struct nlm_host * nlmclnt_lookup_host(struct sockaddr_in *, int, int);
145struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *);
146struct nlm_host * nlm_lookup_host(struct svc_client *,
147					struct sockaddr_in *, int, int);
148struct rpc_clnt * nlm_bind_host(struct nlm_host *);
149void		  nlm_rebind_host(struct nlm_host *);
150struct nlm_host * nlm_get_host(struct nlm_host *);
151void		  nlm_release_host(struct nlm_host *);
152void		  nlm_shutdown_hosts(void);
153
154/*
155 * Server-side lock handling
156 */
157int		  nlmsvc_async_call(struct nlm_rqst *, u32, rpc_action);
158u32		  nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
159					struct nlm_lock *, int, struct nlm_cookie *);
160u32		  nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
161u32		  nlmsvc_testlock(struct nlm_file *, struct nlm_lock *,
162					struct nlm_lock *);
163u32		  nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
164unsigned long	  nlmsvc_retry_blocked(void);
165int		  nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
166					int action);
167
168/*
169 * File handling for the server personality
170 */
171u32		  nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
172					struct nfs_fh *);
173void		  nlm_release_file(struct nlm_file *);
174void		  nlmsvc_mark_resources(void);
175void		  nlmsvc_free_host_resources(struct nlm_host *);
176
177static __inline__ struct inode *
178nlmsvc_file_inode(struct nlm_file *file)
179{
180	return file->f_file.f_dentry->d_inode;
181}
182
183/*
184 * Compare two host addresses (needs modifying for ipv6)
185 */
186static __inline__ int
187nlm_cmp_addr(struct sockaddr_in *sin1, struct sockaddr_in *sin2)
188{
189	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
190}
191
192/*
193 * Compare two NLM locks.
194 * When the second lock is of type F_UNLCK, this acts like a wildcard.
195 */
196static __inline__ int
197nlm_compare_locks(struct file_lock *fl1, struct file_lock *fl2)
198{
199	return	fl1->fl_pid   == fl2->fl_pid
200	     && fl1->fl_start == fl2->fl_start
201	     && fl1->fl_end   == fl2->fl_end
202	     &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
203}
204
205#endif /* __KERNEL__ */
206
207#endif /* LINUX_LOCKD_LOCKD_H */
208