Implement client side NFS locks.

Obtained from: BSD/os
Import Ok'd by: mckusick, jkh, motd on builder.freebsd.org

1 files changed, 112 insertions, 0 deletions

diff --git a/sys/nfsclient/nfs_lock.h b/sys/nfsclient/nfs_lock.h
new file mode 100644
index 0000000..64b6c70
--- /dev/null
+++ b/sys/nfsclient/nfs_lock.h
@@ -0,0 +1,112 @@
+/*-
+ * Copyright (c) 1998 Berkeley Software Design, Inc. All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Berkeley Software Design Inc's name may not be used to endorse or
+ *    promote products derived from this software without specific prior
+ *    written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *      from nfs_lock.h,v 2.2 1998/04/28 19:38:41 don Exp
+ * $FreeBSD$
+ */
+
+/*
+ * lockd uses the nfssvc system call to get the unique kernel services it needs.
+ * It passes in a request structure with a version number at the start.
+ * This prevents libc from needing to change if the information passed 
+ * between lockd and the kernel needs to change.
+ *
+ * If a structure changes, you must bump the version number.
+ */
+
+#include <nfs/nfsproto.h>
+
+
+#define LOCKD_REQ_VERSION	1
+
+struct lockd_req {
+	int			vers;	/* keep in sync with kernel please */
+	int 		op;		/* F_GETLK | F_SETLK | F_UNLCK */
+	int		owner;		/* owner of lock, -1 to allocate one */
+	int		owner_rel_ok;	/* release owner if no locks left ? */
+	int		*owner_ret;	/* owner alloc/free result target */
+	void 		*fh;		/* NFS file handle */
+	size_t 		fh_len;		/* NFS file handle length */
+	u_quad_t 	offset;		/* offset of where to start lock */
+	u_quad_t 	len;		/* length of range to lock */
+	int 		type;		/* F_RDLCK | F_WRLCK | F_UNLCK */
+	struct ucred	cred;		/* user credentials to use for lock */
+	struct sockaddr saddr;		/* XXX how about non AF_INET ?? */
+	int		pid;		/* pid of lock requester */
+};
+
+/* 
+ * The fifo where the kernel writes requests for locks on remote NFS files,
+ * and where lockd reads these requests.
+ *
+ */
+#define	_PATH_LCKFIFO	"/var/run/lock"
+
+/*
+ * This structure is used to uniquely identify the process which originated
+ * a particular message to lockd.  A sequence number is used to differentiate
+ * multiple messages from the same process.  A process start time is used to
+ * detect the unlikely, but possible, event of the recycling of a pid.
+ */
+struct lockd_msg_ident {
+	pid_t		pid;            /* The process ID. */
+	struct timeval	pid_start;	/* Start time of process id */
+	int		msg_seq;	/* Sequence number of message */
+};
+
+#define LOCKD_MSG_VERSION	1
+
+/*
+ * The structure that the kernel hands us for each lock request.
+ */
+typedef struct __lock_msg {
+	int			lm_version;	/* which version is this */
+	struct lockd_msg_ident	lm_msg_ident;	/* originator of the message */
+	struct flock		lm_fl;             /* The lock request. */
+	int			lm_wait;           /* The F_WAIT flag. */
+	int			lm_getlk;		/* is this a F_GETLK request */
+	struct sockaddr 	lm_addr;		/* The address. */
+	int			lm_nfsv3;		/* If NFS version 3. */
+	size_t			lm_fh_len;		/* The file handle length. */
+	struct ucred		lm_cred;		/* user cred for lock req */
+	u_int8_t		lm_fh[NFS_SMALLFH];/* The file handle. */
+} LOCKD_MSG;
+
+#define LOCKD_ANS_VERSION	1
+
+struct lockd_ans {
+	int		la_vers;
+	struct lockd_msg_ident	la_msg_ident;	/* originator of the message */
+	int		la_errno;
+	int		la_set_getlk_pid;		/* use returned pid */
+	int		la_getlk_pid;		/* returned pid for F_GETLK */
+};
+
+#ifdef _KERNEL
+int	nfs_dolock(struct vop_advlock_args *ap);
+int nfslockdans(struct proc *p, struct lockd_ans *ansp);
+int nfslockdreq(struct proc *p, struct lockd_req *reqp);
+#endif