xref: /freebsd/sys/nfs/nfs_lock.h (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
1 /*-
2  * Copyright (c) 1998 Berkeley Software Design, Inc. All rights reserved.
3  * Redistribution and use in source and binary forms, with or without
4  * modification, are permitted provided that the following conditions
5  * are met:
6  * 1. Redistributions of source code must retain the above copyright
7  *    notice, this list of conditions and the following disclaimer.
8  * 2. Redistributions in binary form must reproduce the above copyright
9  *    notice, this list of conditions and the following disclaimer in the
10  *    documentation and/or other materials provided with the distribution.
11  * 3. Berkeley Software Design Inc's name may not be used to endorse or
12  *    promote products derived from this software without specific prior
13  *    written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  *      from nfs_lock.h,v 2.2 1998/04/28 19:38:41 don Exp
28  * $FreeBSD$
29  */
30 
31 /*
32  * lockd uses the nfssvc system call to get the unique kernel services it needs.
33  * It passes in a request structure with a version number at the start.
34  * This prevents libc from needing to change if the information passed
35  * between lockd and the kernel needs to change.
36  *
37  * If a structure changes, you must bump the version number.
38  */
39 
40 #include <nfs/nfsproto.h>
41 
42 
43 #define LOCKD_REQ_VERSION	1
44 
45 struct lockd_req {
46 	int			vers;	/* keep in sync with kernel please */
47 	int 		op;		/* F_GETLK | F_SETLK | F_UNLCK */
48 	int		owner;		/* owner of lock, -1 to allocate one */
49 	int		owner_rel_ok;	/* release owner if no locks left ? */
50 	int		*owner_ret;	/* owner alloc/free result target */
51 	void 		*fh;		/* NFS file handle */
52 	size_t 		fh_len;		/* NFS file handle length */
53 	u_quad_t 	offset;		/* offset of where to start lock */
54 	u_quad_t 	len;		/* length of range to lock */
55 	int 		type;		/* F_RDLCK | F_WRLCK | F_UNLCK */
56 	struct ucred	cred;		/* user credentials to use for lock */
57 	struct sockaddr saddr;		/* XXX how about non AF_INET ?? */
58 	int		pid;		/* pid of lock requester */
59 };
60 
61 /*
62  * The fifo where the kernel writes requests for locks on remote NFS files,
63  * and where lockd reads these requests.
64  *
65  */
66 #define	_PATH_LCKFIFO	"/var/run/lock"
67 
68 /*
69  * This structure is used to uniquely identify the process which originated
70  * a particular message to lockd.  A sequence number is used to differentiate
71  * multiple messages from the same process.  A process start time is used to
72  * detect the unlikely, but possible, event of the recycling of a pid.
73  */
74 struct lockd_msg_ident {
75 	pid_t		pid;            /* The process ID. */
76 	struct timeval	pid_start;	/* Start time of process id */
77 	int		msg_seq;	/* Sequence number of message */
78 };
79 
80 #define LOCKD_MSG_VERSION	1
81 
82 /*
83  * The structure that the kernel hands us for each lock request.
84  */
85 typedef struct __lock_msg {
86 	int			lm_version;	/* which version is this */
87 	struct lockd_msg_ident	lm_msg_ident;	/* originator of the message */
88 	struct flock		lm_fl;             /* The lock request. */
89 	int			lm_wait;           /* The F_WAIT flag. */
90 	int			lm_getlk;		/* is this a F_GETLK request */
91 	struct sockaddr 	lm_addr;		/* The address. */
92 	int			lm_nfsv3;		/* If NFS version 3. */
93 	size_t			lm_fh_len;		/* The file handle length. */
94 	struct ucred		lm_cred;		/* user cred for lock req */
95 	u_int8_t		lm_fh[NFS_SMALLFH];/* The file handle. */
96 } LOCKD_MSG;
97 
98 #define LOCKD_ANS_VERSION	1
99 
100 struct lockd_ans {
101 	int		la_vers;
102 	struct lockd_msg_ident	la_msg_ident;	/* originator of the message */
103 	int		la_errno;
104 	int		la_set_getlk_pid;		/* use returned pid */
105 	int		la_getlk_pid;		/* returned pid for F_GETLK */
106 };
107 
108 #ifdef _KERNEL
109 int	nfs_dolock(struct vop_advlock_args *ap);
110 int nfslockdans(struct proc *p, struct lockd_ans *ansp);
111 int nfslockdreq(struct proc *p, struct lockd_req *reqp);
112 #endif
113