lockd.h revision f2af793db02d2c2f677bdb5bf8e0efdcbf9c0256 
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/fs.h>
16#include <linux/kref.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 hlist_node	h_hash;		/* doubly linked list */
41	struct sockaddr_in	h_addr;		/* peer address */
42	struct rpc_clnt	*	h_rpcclnt;	/* RPC client to talk to peer */
43	char *			h_name;		/* 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	wait_queue_head_t	h_gracewait;	/* wait while reclaiming */
51	struct rw_semaphore	h_rwsem;	/* Reboot recovery lock */
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 mutex		h_mutex;	/* 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	struct list_head	h_granted;	/* Locks in GRANTED state */
62	struct list_head	h_reclaim;	/* Locks in RECLAIM state */
63	struct nsm_handle *	h_nsmhandle;	/* NSM status handle */
64};
65
66struct nsm_handle {
67	struct list_head	sm_link;
68	atomic_t		sm_count;
69	char *			sm_name;
70	struct sockaddr_in	sm_addr;
71	unsigned int		sm_monitored : 1,
72				sm_sticky : 1;	/* don't unmonitor */
73};
74
75/*
76 * Map an fl_owner_t into a unique 32-bit "pid"
77 */
78struct nlm_lockowner {
79	struct list_head list;
80	atomic_t count;
81
82	struct nlm_host *host;
83	fl_owner_t owner;
84	uint32_t pid;
85};
86
87struct nlm_wait;
88
89/*
90 * Memory chunk for NLM client RPC request.
91 */
92#define NLMCLNT_OHSIZE		(sizeof(utsname()->nodename)+10)
93struct nlm_rqst {
94	unsigned int		a_flags;	/* initial RPC task flags */
95	struct nlm_host *	a_host;		/* host handle */
96	struct nlm_args		a_args;		/* arguments */
97	struct nlm_res		a_res;		/* result */
98	struct nlm_block *	a_block;
99	unsigned int		a_retries;	/* Retry count */
100	u8			a_owner[NLMCLNT_OHSIZE];
101};
102
103/*
104 * This struct describes a file held open by lockd on behalf of
105 * an NFS client.
106 */
107struct nlm_file {
108	struct hlist_node	f_list;		/* linked list */
109	struct nfs_fh		f_handle;	/* NFS file handle */
110	struct file *		f_file;		/* VFS file pointer */
111	struct nlm_share *	f_shares;	/* DOS shares */
112	struct list_head	f_blocks;	/* blocked locks */
113	unsigned int		f_locks;	/* guesstimate # of locks */
114	unsigned int		f_count;	/* reference count */
115	struct semaphore	f_sema;		/* avoid concurrent access */
116};
117
118/*
119 * This is a server block (i.e. a lock requested by some client which
120 * couldn't be granted because of a conflicting lock).
121 */
122#define NLM_NEVER		(~(unsigned long) 0)
123struct nlm_block {
124	struct kref		b_count;	/* Reference count */
125	struct list_head	b_list;		/* linked list of all blocks */
126	struct list_head	b_flist;	/* linked list (per file) */
127	struct nlm_rqst	*	b_call;		/* RPC args & callback info */
128	struct svc_serv *	b_daemon;	/* NLM service */
129	struct nlm_host *	b_host;		/* host handle for RPC clnt */
130	unsigned long		b_when;		/* next re-xmit */
131	unsigned int		b_id;		/* block id */
132	unsigned char		b_granted;	/* VFS granted lock */
133	struct nlm_file *	b_file;		/* file in question */
134};
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 * nlm_alloc_call(struct nlm_host *host);
151void		  nlm_release_call(struct nlm_rqst *);
152int		  nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
153int		  nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
154struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
155void		  nlmclnt_finish_block(struct nlm_wait *block);
156int		  nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
157u32		  nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *);
158void		  nlmclnt_recovery(struct nlm_host *);
159int		  nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
160
161/*
162 * Host cache
163 */
164struct nlm_host * nlmclnt_lookup_host(const struct sockaddr_in *, int, int, const char *, int);
165struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *, const char *, int);
166struct nlm_host * nlm_lookup_host(int server, const struct sockaddr_in *, int, int, const char *, int);
167struct rpc_clnt * nlm_bind_host(struct nlm_host *);
168void		  nlm_rebind_host(struct nlm_host *);
169struct nlm_host * nlm_get_host(struct nlm_host *);
170void		  nlm_release_host(struct nlm_host *);
171void		  nlm_shutdown_hosts(void);
172extern struct nlm_host *nlm_find_client(void);
173extern void	  nlm_host_rebooted(const struct sockaddr_in *, const char *, int, u32);
174struct nsm_handle *nsm_find(const struct sockaddr_in *, const char *, int);
175void		  nsm_release(struct nsm_handle *);
176
177
178/*
179 * This is used in garbage collection and resource reclaim
180 * A return value != 0 means destroy the lock/block/share
181 */
182typedef int	  (*nlm_host_match_fn_t)(struct nlm_host *cur, struct nlm_host *ref);
183
184/*
185 * Server-side lock handling
186 */
187u32		  nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
188					struct nlm_lock *, int, struct nlm_cookie *);
189u32		  nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
190u32		  nlmsvc_testlock(struct nlm_file *, struct nlm_lock *,
191					struct nlm_lock *);
192u32		  nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
193unsigned long	  nlmsvc_retry_blocked(void);
194void		  nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
195					nlm_host_match_fn_t match);
196void	  nlmsvc_grant_reply(struct svc_rqst *, struct nlm_cookie *, u32);
197
198/*
199 * File handling for the server personality
200 */
201u32		  nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
202					struct nfs_fh *);
203void		  nlm_release_file(struct nlm_file *);
204void		  nlmsvc_mark_resources(void);
205void		  nlmsvc_free_host_resources(struct nlm_host *);
206void		  nlmsvc_invalidate_all(void);
207
208static __inline__ struct inode *
209nlmsvc_file_inode(struct nlm_file *file)
210{
211	return file->f_file->f_dentry->d_inode;
212}
213
214/*
215 * Compare two host addresses (needs modifying for ipv6)
216 */
217static __inline__ int
218nlm_cmp_addr(const struct sockaddr_in *sin1, const struct sockaddr_in *sin2)
219{
220	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
221}
222
223/*
224 * Compare two NLM locks.
225 * When the second lock is of type F_UNLCK, this acts like a wildcard.
226 */
227static __inline__ int
228nlm_compare_locks(const struct file_lock *fl1, const struct file_lock *fl2)
229{
230	return	fl1->fl_pid   == fl2->fl_pid
231	     && fl1->fl_owner == fl2->fl_owner
232	     && fl1->fl_start == fl2->fl_start
233	     && fl1->fl_end   == fl2->fl_end
234	     &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
235}
236
237extern struct lock_manager_operations nlmsvc_lock_operations;
238
239#endif /* __KERNEL__ */
240
241#endif /* LINUX_LOCKD_LOCKD_H */
242