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	wait_queue_head_t	h_gracewait;	/* wait while reclaiming */
50	struct rw_semaphore	h_rwsem;	/* Reboot recovery lock */
51	u32			h_state;	/* pseudo-state counter */
52	u32			h_nsmstate;	/* true remote NSM state */
53	u32			h_pidcount;	/* Pseudopids */
54	atomic_t		h_count;	/* reference count */
55	struct mutex		h_mutex;	/* mutex for pmap binding */
56	unsigned long		h_nextrebind;	/* next portmap call */
57	unsigned long		h_expires;	/* eligible for GC */
58	struct list_head	h_lockowners;	/* Lockowners for the client */
59	spinlock_t		h_lock;
60	struct list_head	h_granted;	/* Locks in GRANTED state */
61	struct list_head	h_reclaim;	/* Locks in RECLAIM state */
62	struct nsm_handle *	h_nsmhandle;	/* NSM status handle */
63};
64
65struct nsm_handle {
66	struct list_head	sm_link;
67	atomic_t		sm_count;
68	char *			sm_name;
69	struct sockaddr_in	sm_addr;
70	unsigned int		sm_monitored : 1,
71				sm_sticky : 1;	/* don't unmonitor */
72};
73
74/*
75 * Map an fl_owner_t into a unique 32-bit "pid"
76 */
77struct nlm_lockowner {
78	struct list_head list;
79	atomic_t count;
80
81	struct nlm_host *host;
82	fl_owner_t owner;
83	uint32_t pid;
84};
85
86struct nlm_wait;
87
88/*
89 * Memory chunk for NLM client RPC request.
90 */
91#define NLMCLNT_OHSIZE		((__NEW_UTS_LEN) + 10u)
92struct nlm_rqst {
93	unsigned int		a_flags;	/* initial RPC task flags */
94	struct nlm_host *	a_host;		/* host handle */
95	struct nlm_args		a_args;		/* arguments */
96	struct nlm_res		a_res;		/* result */
97	struct nlm_block *	a_block;
98	unsigned int		a_retries;	/* Retry count */
99	u8			a_owner[NLMCLNT_OHSIZE];
100};
101
102/*
103 * This struct describes a file held open by lockd on behalf of
104 * an NFS client.
105 */
106struct nlm_file {
107	struct hlist_node	f_list;		/* linked list */
108	struct nfs_fh		f_handle;	/* NFS file handle */
109	struct file *		f_file;		/* VFS file pointer */
110	struct nlm_share *	f_shares;	/* DOS shares */
111	struct list_head	f_blocks;	/* blocked locks */
112	unsigned int		f_locks;	/* guesstimate # of locks */
113	unsigned int		f_count;	/* reference count */
114	struct mutex		f_mutex;	/* avoid concurrent access */
115};
116
117/*
118 * This is a server block (i.e. a lock requested by some client which
119 * couldn't be granted because of a conflicting lock).
120 */
121#define NLM_NEVER		(~(unsigned long) 0)
122/* timeout on non-blocking call: */
123#define NLM_TIMEOUT		(7 * HZ)
124
125struct nlm_block {
126	struct kref		b_count;	/* Reference count */
127	struct list_head	b_list;		/* linked list of all blocks */
128	struct list_head	b_flist;	/* linked list (per file) */
129	struct nlm_rqst	*	b_call;		/* RPC args & callback info */
130	struct svc_serv *	b_daemon;	/* NLM service */
131	struct nlm_host *	b_host;		/* host handle for RPC clnt */
132	unsigned long		b_when;		/* next re-xmit */
133	unsigned int		b_id;		/* block id */
134	unsigned char		b_granted;	/* VFS granted lock */
135	struct nlm_file *	b_file;		/* file in question */
136	struct cache_req *	b_cache_req;	/* deferred request handling */
137	struct file_lock *	b_fl;		/* set for GETLK */
138	struct cache_deferred_req * b_deferred_req;
139	unsigned int		b_flags;	/* block flags */
140#define B_QUEUED		1	/* lock queued */
141#define B_GOT_CALLBACK		2	/* got lock or conflicting lock */
142#define B_TIMED_OUT		4	/* filesystem too slow to respond */
143};
144
145/*
146 * Global variables
147 */
148extern struct rpc_program	nlm_program;
149extern struct svc_procedure	nlmsvc_procedures[];
150#ifdef CONFIG_LOCKD_V4
151extern struct svc_procedure	nlmsvc_procedures4[];
152#endif
153extern int			nlmsvc_grace_period;
154extern unsigned long		nlmsvc_timeout;
155extern int			nsm_use_hostnames;
156
157/*
158 * Lockd client functions
159 */
160struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
161void		  nlm_release_call(struct nlm_rqst *);
162int		  nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
163int		  nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
164struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
165void		  nlmclnt_finish_block(struct nlm_wait *block);
166int		  nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
167__be32		  nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *);
168void		  nlmclnt_recovery(struct nlm_host *);
169int		  nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
170void		  nlmclnt_next_cookie(struct nlm_cookie *);
171
172/*
173 * Host cache
174 */
175struct nlm_host * nlmclnt_lookup_host(const struct sockaddr_in *, int, int, const char *, int);
176struct nlm_host * nlmsvc_lookup_host(struct svc_rqst *, const char *, int);
177struct rpc_clnt * nlm_bind_host(struct nlm_host *);
178void		  nlm_rebind_host(struct nlm_host *);
179struct nlm_host * nlm_get_host(struct nlm_host *);
180void		  nlm_release_host(struct nlm_host *);
181void		  nlm_shutdown_hosts(void);
182extern void	  nlm_host_rebooted(const struct sockaddr_in *, const char *, int, u32);
183void		  nsm_release(struct nsm_handle *);
184
185
186/*
187 * This is used in garbage collection and resource reclaim
188 * A return value != 0 means destroy the lock/block/share
189 */
190typedef int	  (*nlm_host_match_fn_t)(struct nlm_host *cur, struct nlm_host *ref);
191
192/*
193 * Server-side lock handling
194 */
195__be32		  nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
196					struct nlm_lock *, int, struct nlm_cookie *);
197__be32		  nlmsvc_unlock(struct nlm_file *, struct nlm_lock *);
198__be32		  nlmsvc_testlock(struct svc_rqst *, struct nlm_file *,
199			struct nlm_lock *, struct nlm_lock *, struct nlm_cookie *);
200__be32		  nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
201unsigned long	  nlmsvc_retry_blocked(void);
202void		  nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
203					nlm_host_match_fn_t match);
204void		  nlmsvc_grant_reply(struct nlm_cookie *, __be32);
205
206/*
207 * File handling for the server personality
208 */
209__be32		  nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
210					struct nfs_fh *);
211void		  nlm_release_file(struct nlm_file *);
212void		  nlmsvc_mark_resources(void);
213void		  nlmsvc_free_host_resources(struct nlm_host *);
214void		  nlmsvc_invalidate_all(void);
215
216static __inline__ struct inode *
217nlmsvc_file_inode(struct nlm_file *file)
218{
219	return file->f_file->f_path.dentry->d_inode;
220}
221
222/*
223 * Compare two host addresses (needs modifying for ipv6)
224 */
225static __inline__ int
226nlm_cmp_addr(const struct sockaddr_in *sin1, const struct sockaddr_in *sin2)
227{
228	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
229}
230
231/*
232 * Compare two NLM locks.
233 * When the second lock is of type F_UNLCK, this acts like a wildcard.
234 */
235static __inline__ int
236nlm_compare_locks(const struct file_lock *fl1, const struct file_lock *fl2)
237{
238	return	fl1->fl_pid   == fl2->fl_pid
239	     && fl1->fl_owner == fl2->fl_owner
240	     && fl1->fl_start == fl2->fl_start
241	     && fl1->fl_end   == fl2->fl_end
242	     &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
243}
244
245extern struct lock_manager_operations nlmsvc_lock_operations;
246
247#endif /* __KERNEL__ */
248
249#endif /* LINUX_LOCKD_LOCKD_H */
250