801 lines
20 KiB
C
801 lines
20 KiB
C
/*
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* Copyright (c) 1982, 1986, 1989, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Scooter Morris at Genentech Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)ufs_lockf.c 8.3 (Berkeley) 1/6/94
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* $Id: kern_lockf.c,v 1.17 1997/12/05 19:55:38 bde Exp $
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*/
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#include "opt_debug_lockf.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/lock.h>
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#include <sys/proc.h>
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#include <sys/unistd.h>
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#include <sys/vnode.h>
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#include <sys/malloc.h>
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#include <sys/fcntl.h>
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#include <sys/lockf.h>
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/*
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* This variable controls the maximum number of processes that will
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* be checked in doing deadlock detection.
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*/
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static int maxlockdepth = MAXDEPTH;
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#ifdef LOCKF_DEBUG
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#include <sys/kernel.h>
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#include <sys/sysctl.h>
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#include <ufs/ufs/quota.h>
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#include <ufs/ufs/inode.h>
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static int lockf_debug = 0;
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SYSCTL_INT(_debug, OID_AUTO, lockf_debug, CTLFLAG_RW, &lockf_debug, 0, "");
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#endif
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static MALLOC_DEFINE(M_LOCKF, "lockf", "Byte-range locking structures");
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#define NOLOCKF (struct lockf *)0
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#define SELF 0x1
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#define OTHERS 0x2
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static int lf_clearlock __P((struct lockf *));
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static int lf_findoverlap __P((struct lockf *,
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struct lockf *, int, struct lockf ***, struct lockf **));
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static struct lockf *
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lf_getblock __P((struct lockf *));
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static int lf_getlock __P((struct lockf *, struct flock *));
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static int lf_setlock __P((struct lockf *));
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static void lf_split __P((struct lockf *, struct lockf *));
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static void lf_wakelock __P((struct lockf *));
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/*
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* Advisory record locking support
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*/
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int
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lf_advlock(ap, head, size)
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struct vop_advlock_args /* {
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struct vnode *a_vp;
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caddr_t a_id;
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int a_op;
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struct flock *a_fl;
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int a_flags;
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} */ *ap;
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struct lockf **head;
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u_quad_t size;
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{
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register struct flock *fl = ap->a_fl;
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register struct lockf *lock;
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off_t start, end;
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int error;
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/*
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* Convert the flock structure into a start and end.
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*/
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switch (fl->l_whence) {
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case SEEK_SET:
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case SEEK_CUR:
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/*
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* Caller is responsible for adding any necessary offset
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* when SEEK_CUR is used.
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*/
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start = fl->l_start;
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break;
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case SEEK_END:
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start = size + fl->l_start;
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break;
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default:
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return (EINVAL);
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}
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if (start < 0)
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return (EINVAL);
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if (fl->l_len == 0)
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end = -1;
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else {
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end = start + fl->l_len - 1;
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if (end < start)
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return (EINVAL);
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}
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/*
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* Avoid the common case of unlocking when inode has no locks.
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*/
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if (*head == (struct lockf *)0) {
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if (ap->a_op != F_SETLK) {
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fl->l_type = F_UNLCK;
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return (0);
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}
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}
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/*
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* Create the lockf structure
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*/
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MALLOC(lock, struct lockf *, sizeof *lock, M_LOCKF, M_WAITOK);
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lock->lf_start = start;
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lock->lf_end = end;
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lock->lf_id = ap->a_id;
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/* lock->lf_inode = ip; */ /* XXX JH */
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lock->lf_type = fl->l_type;
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lock->lf_head = head;
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lock->lf_next = (struct lockf *)0;
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TAILQ_INIT(&lock->lf_blkhd);
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lock->lf_flags = ap->a_flags;
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/*
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* Do the requested operation.
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*/
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switch(ap->a_op) {
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case F_SETLK:
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return (lf_setlock(lock));
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case F_UNLCK:
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error = lf_clearlock(lock);
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FREE(lock, M_LOCKF);
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return (error);
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case F_GETLK:
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error = lf_getlock(lock, fl);
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FREE(lock, M_LOCKF);
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return (error);
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default:
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free(lock, M_LOCKF);
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return (EINVAL);
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}
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/* NOTREACHED */
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}
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/*
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* Set a byte-range lock.
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*/
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static int
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lf_setlock(lock)
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register struct lockf *lock;
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{
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register struct lockf *block;
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struct lockf **head = lock->lf_head;
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struct lockf **prev, *overlap, *ltmp;
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static char lockstr[] = "lockf";
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int ovcase, priority, needtolink, error;
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#ifdef LOCKF_DEBUG
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if (lockf_debug & 1)
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lf_print("lf_setlock", lock);
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#endif /* LOCKF_DEBUG */
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/*
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* Set the priority
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*/
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priority = PLOCK;
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if (lock->lf_type == F_WRLCK)
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priority += 4;
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priority |= PCATCH;
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/*
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* Scan lock list for this file looking for locks that would block us.
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*/
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while ((block = lf_getblock(lock))) {
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/*
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* Free the structure and return if nonblocking.
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*/
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if ((lock->lf_flags & F_WAIT) == 0) {
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FREE(lock, M_LOCKF);
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return (EAGAIN);
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}
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/*
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* We are blocked. Since flock style locks cover
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* the whole file, there is no chance for deadlock.
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* For byte-range locks we must check for deadlock.
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*
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* Deadlock detection is done by looking through the
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* wait channels to see if there are any cycles that
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* involve us. MAXDEPTH is set just to make sure we
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* do not go off into neverland.
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*/
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if ((lock->lf_flags & F_POSIX) &&
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(block->lf_flags & F_POSIX)) {
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register struct proc *wproc;
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register struct lockf *waitblock;
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int i = 0;
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/* The block is waiting on something */
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wproc = (struct proc *)block->lf_id;
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while (wproc->p_wchan &&
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(wproc->p_wmesg == lockstr) &&
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(i++ < maxlockdepth)) {
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waitblock = (struct lockf *)wproc->p_wchan;
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/* Get the owner of the blocking lock */
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waitblock = waitblock->lf_next;
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if ((waitblock->lf_flags & F_POSIX) == 0)
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break;
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wproc = (struct proc *)waitblock->lf_id;
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if (wproc == (struct proc *)lock->lf_id) {
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free(lock, M_LOCKF);
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return (EDEADLK);
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}
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}
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}
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/*
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* For flock type locks, we must first remove
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* any shared locks that we hold before we sleep
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* waiting for an exclusive lock.
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*/
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if ((lock->lf_flags & F_FLOCK) &&
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lock->lf_type == F_WRLCK) {
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lock->lf_type = F_UNLCK;
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(void) lf_clearlock(lock);
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lock->lf_type = F_WRLCK;
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}
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/*
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* Add our lock to the blocked list and sleep until we're free.
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* Remember who blocked us (for deadlock detection).
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*/
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lock->lf_next = block;
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TAILQ_INSERT_TAIL(&block->lf_blkhd, lock, lf_block);
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#ifdef LOCKF_DEBUG
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if (lockf_debug & 1) {
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lf_print("lf_setlock: blocking on", block);
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lf_printlist("lf_setlock", block);
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}
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#endif /* LOCKF_DEBUG */
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if ((error = tsleep((caddr_t)lock, priority, lockstr, 0))) {
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/*
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* We may have been awakened by a signal (in
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* which case we must remove ourselves from the
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* blocked list) and/or by another process
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* releasing a lock (in which case we have already
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* been removed from the blocked list and our
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* lf_next field set to NOLOCKF).
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*/
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if (lock->lf_next)
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TAILQ_REMOVE(&lock->lf_next->lf_blkhd, lock,
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lf_block);
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free(lock, M_LOCKF);
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return (error);
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}
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}
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/*
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* No blocks!! Add the lock. Note that we will
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* downgrade or upgrade any overlapping locks this
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* process already owns.
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*
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* Skip over locks owned by other processes.
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* Handle any locks that overlap and are owned by ourselves.
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*/
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prev = head;
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block = *head;
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needtolink = 1;
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for (;;) {
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ovcase = lf_findoverlap(block, lock, SELF, &prev, &overlap);
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if (ovcase)
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block = overlap->lf_next;
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/*
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* Six cases:
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* 0) no overlap
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* 1) overlap == lock
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* 2) overlap contains lock
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* 3) lock contains overlap
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* 4) overlap starts before lock
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* 5) overlap ends after lock
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*/
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switch (ovcase) {
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case 0: /* no overlap */
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if (needtolink) {
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*prev = lock;
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lock->lf_next = overlap;
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}
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break;
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case 1: /* overlap == lock */
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/*
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* If downgrading lock, others may be
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* able to acquire it.
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*/
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if (lock->lf_type == F_RDLCK &&
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overlap->lf_type == F_WRLCK)
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lf_wakelock(overlap);
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overlap->lf_type = lock->lf_type;
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FREE(lock, M_LOCKF);
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lock = overlap; /* for debug output below */
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break;
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case 2: /* overlap contains lock */
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/*
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* Check for common starting point and different types.
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*/
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if (overlap->lf_type == lock->lf_type) {
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free(lock, M_LOCKF);
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lock = overlap; /* for debug output below */
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break;
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}
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if (overlap->lf_start == lock->lf_start) {
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*prev = lock;
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lock->lf_next = overlap;
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overlap->lf_start = lock->lf_end + 1;
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} else
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lf_split(overlap, lock);
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lf_wakelock(overlap);
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break;
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case 3: /* lock contains overlap */
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/*
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* If downgrading lock, others may be able to
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* acquire it, otherwise take the list.
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*/
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if (lock->lf_type == F_RDLCK &&
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overlap->lf_type == F_WRLCK) {
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lf_wakelock(overlap);
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} else {
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while (ltmp = overlap->lf_blkhd.tqh_first) {
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TAILQ_REMOVE(&overlap->lf_blkhd, ltmp,
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lf_block);
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TAILQ_INSERT_TAIL(&lock->lf_blkhd,
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ltmp, lf_block);
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}
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}
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/*
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* Add the new lock if necessary and delete the overlap.
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*/
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if (needtolink) {
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*prev = lock;
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lock->lf_next = overlap->lf_next;
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prev = &lock->lf_next;
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needtolink = 0;
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} else
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*prev = overlap->lf_next;
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free(overlap, M_LOCKF);
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continue;
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case 4: /* overlap starts before lock */
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/*
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* Add lock after overlap on the list.
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*/
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lock->lf_next = overlap->lf_next;
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overlap->lf_next = lock;
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overlap->lf_end = lock->lf_start - 1;
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prev = &lock->lf_next;
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lf_wakelock(overlap);
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needtolink = 0;
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continue;
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case 5: /* overlap ends after lock */
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/*
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* Add the new lock before overlap.
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*/
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if (needtolink) {
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*prev = lock;
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lock->lf_next = overlap;
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}
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overlap->lf_start = lock->lf_end + 1;
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lf_wakelock(overlap);
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break;
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}
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break;
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}
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#ifdef LOCKF_DEBUG
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if (lockf_debug & 1) {
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lf_print("lf_setlock: got the lock", lock);
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lf_printlist("lf_setlock", lock);
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}
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#endif /* LOCKF_DEBUG */
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return (0);
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}
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/*
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* Remove a byte-range lock on an inode.
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*
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* Generally, find the lock (or an overlap to that lock)
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* and remove it (or shrink it), then wakeup anyone we can.
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*/
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static int
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lf_clearlock(unlock)
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register struct lockf *unlock;
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{
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struct lockf **head = unlock->lf_head;
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register struct lockf *lf = *head;
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struct lockf *overlap, **prev;
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int ovcase;
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if (lf == NOLOCKF)
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return (0);
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#ifdef LOCKF_DEBUG
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if (unlock->lf_type != F_UNLCK)
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panic("lf_clearlock: bad type");
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if (lockf_debug & 1)
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lf_print("lf_clearlock", unlock);
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#endif /* LOCKF_DEBUG */
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prev = head;
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while ((ovcase = lf_findoverlap(lf, unlock, SELF, &prev, &overlap))) {
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/*
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* Wakeup the list of locks to be retried.
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*/
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lf_wakelock(overlap);
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switch (ovcase) {
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case 1: /* overlap == lock */
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*prev = overlap->lf_next;
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FREE(overlap, M_LOCKF);
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break;
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case 2: /* overlap contains lock: split it */
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if (overlap->lf_start == unlock->lf_start) {
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overlap->lf_start = unlock->lf_end + 1;
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break;
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}
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lf_split(overlap, unlock);
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overlap->lf_next = unlock->lf_next;
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break;
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case 3: /* lock contains overlap */
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*prev = overlap->lf_next;
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lf = overlap->lf_next;
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free(overlap, M_LOCKF);
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continue;
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case 4: /* overlap starts before lock */
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overlap->lf_end = unlock->lf_start - 1;
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prev = &overlap->lf_next;
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lf = overlap->lf_next;
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continue;
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case 5: /* overlap ends after lock */
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overlap->lf_start = unlock->lf_end + 1;
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break;
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}
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break;
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}
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#ifdef LOCKF_DEBUG
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if (lockf_debug & 1)
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lf_printlist("lf_clearlock", unlock);
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#endif /* LOCKF_DEBUG */
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return (0);
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}
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/*
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* Check whether there is a blocking lock,
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* and if so return its process identifier.
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*/
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static int
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lf_getlock(lock, fl)
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register struct lockf *lock;
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register struct flock *fl;
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{
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register struct lockf *block;
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#ifdef LOCKF_DEBUG
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if (lockf_debug & 1)
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lf_print("lf_getlock", lock);
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#endif /* LOCKF_DEBUG */
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if ((block = lf_getblock(lock))) {
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fl->l_type = block->lf_type;
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fl->l_whence = SEEK_SET;
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fl->l_start = block->lf_start;
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if (block->lf_end == -1)
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fl->l_len = 0;
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else
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fl->l_len = block->lf_end - block->lf_start + 1;
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if (block->lf_flags & F_POSIX)
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fl->l_pid = ((struct proc *)(block->lf_id))->p_pid;
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else
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fl->l_pid = -1;
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} else {
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fl->l_type = F_UNLCK;
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}
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return (0);
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}
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/*
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* Walk the list of locks for an inode and
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* return the first blocking lock.
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*/
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static struct lockf *
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lf_getblock(lock)
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register struct lockf *lock;
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{
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struct lockf **prev, *overlap, *lf = *(lock->lf_head);
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int ovcase;
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prev = lock->lf_head;
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while ((ovcase = lf_findoverlap(lf, lock, OTHERS, &prev, &overlap))) {
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/*
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* We've found an overlap, see if it blocks us
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*/
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if ((lock->lf_type == F_WRLCK || overlap->lf_type == F_WRLCK))
|
|
return (overlap);
|
|
/*
|
|
* Nope, point to the next one on the list and
|
|
* see if it blocks us
|
|
*/
|
|
lf = overlap->lf_next;
|
|
}
|
|
return (NOLOCKF);
|
|
}
|
|
|
|
/*
|
|
* Walk the list of locks for an inode to
|
|
* find an overlapping lock (if any).
|
|
*
|
|
* NOTE: this returns only the FIRST overlapping lock. There
|
|
* may be more than one.
|
|
*/
|
|
static int
|
|
lf_findoverlap(lf, lock, type, prev, overlap)
|
|
register struct lockf *lf;
|
|
struct lockf *lock;
|
|
int type;
|
|
struct lockf ***prev;
|
|
struct lockf **overlap;
|
|
{
|
|
off_t start, end;
|
|
|
|
*overlap = lf;
|
|
if (lf == NOLOCKF)
|
|
return (0);
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
lf_print("lf_findoverlap: looking for overlap in", lock);
|
|
#endif /* LOCKF_DEBUG */
|
|
start = lock->lf_start;
|
|
end = lock->lf_end;
|
|
while (lf != NOLOCKF) {
|
|
if (((type & SELF) && lf->lf_id != lock->lf_id) ||
|
|
((type & OTHERS) && lf->lf_id == lock->lf_id)) {
|
|
*prev = &lf->lf_next;
|
|
*overlap = lf = lf->lf_next;
|
|
continue;
|
|
}
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
lf_print("\tchecking", lf);
|
|
#endif /* LOCKF_DEBUG */
|
|
/*
|
|
* OK, check for overlap
|
|
*
|
|
* Six cases:
|
|
* 0) no overlap
|
|
* 1) overlap == lock
|
|
* 2) overlap contains lock
|
|
* 3) lock contains overlap
|
|
* 4) overlap starts before lock
|
|
* 5) overlap ends after lock
|
|
*/
|
|
if ((lf->lf_end != -1 && start > lf->lf_end) ||
|
|
(end != -1 && lf->lf_start > end)) {
|
|
/* Case 0 */
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
printf("no overlap\n");
|
|
#endif /* LOCKF_DEBUG */
|
|
if ((type & SELF) && end != -1 && lf->lf_start > end)
|
|
return (0);
|
|
*prev = &lf->lf_next;
|
|
*overlap = lf = lf->lf_next;
|
|
continue;
|
|
}
|
|
if ((lf->lf_start == start) && (lf->lf_end == end)) {
|
|
/* Case 1 */
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
printf("overlap == lock\n");
|
|
#endif /* LOCKF_DEBUG */
|
|
return (1);
|
|
}
|
|
if ((lf->lf_start <= start) &&
|
|
(end != -1) &&
|
|
((lf->lf_end >= end) || (lf->lf_end == -1))) {
|
|
/* Case 2 */
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
printf("overlap contains lock\n");
|
|
#endif /* LOCKF_DEBUG */
|
|
return (2);
|
|
}
|
|
if (start <= lf->lf_start &&
|
|
(end == -1 ||
|
|
(lf->lf_end != -1 && end >= lf->lf_end))) {
|
|
/* Case 3 */
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
printf("lock contains overlap\n");
|
|
#endif /* LOCKF_DEBUG */
|
|
return (3);
|
|
}
|
|
if ((lf->lf_start < start) &&
|
|
((lf->lf_end >= start) || (lf->lf_end == -1))) {
|
|
/* Case 4 */
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
printf("overlap starts before lock\n");
|
|
#endif /* LOCKF_DEBUG */
|
|
return (4);
|
|
}
|
|
if ((lf->lf_start > start) &&
|
|
(end != -1) &&
|
|
((lf->lf_end > end) || (lf->lf_end == -1))) {
|
|
/* Case 5 */
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
printf("overlap ends after lock\n");
|
|
#endif /* LOCKF_DEBUG */
|
|
return (5);
|
|
}
|
|
panic("lf_findoverlap: default");
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Split a lock and a contained region into
|
|
* two or three locks as necessary.
|
|
*/
|
|
static void
|
|
lf_split(lock1, lock2)
|
|
register struct lockf *lock1;
|
|
register struct lockf *lock2;
|
|
{
|
|
register struct lockf *splitlock;
|
|
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2) {
|
|
lf_print("lf_split", lock1);
|
|
lf_print("splitting from", lock2);
|
|
}
|
|
#endif /* LOCKF_DEBUG */
|
|
/*
|
|
* Check to see if spliting into only two pieces.
|
|
*/
|
|
if (lock1->lf_start == lock2->lf_start) {
|
|
lock1->lf_start = lock2->lf_end + 1;
|
|
lock2->lf_next = lock1;
|
|
return;
|
|
}
|
|
if (lock1->lf_end == lock2->lf_end) {
|
|
lock1->lf_end = lock2->lf_start - 1;
|
|
lock2->lf_next = lock1->lf_next;
|
|
lock1->lf_next = lock2;
|
|
return;
|
|
}
|
|
/*
|
|
* Make a new lock consisting of the last part of
|
|
* the encompassing lock
|
|
*/
|
|
MALLOC(splitlock, struct lockf *, sizeof *splitlock, M_LOCKF, M_WAITOK);
|
|
bcopy((caddr_t)lock1, (caddr_t)splitlock, sizeof *splitlock);
|
|
splitlock->lf_start = lock2->lf_end + 1;
|
|
TAILQ_INIT(&splitlock->lf_blkhd);
|
|
lock1->lf_end = lock2->lf_start - 1;
|
|
/*
|
|
* OK, now link it in
|
|
*/
|
|
splitlock->lf_next = lock1->lf_next;
|
|
lock2->lf_next = splitlock;
|
|
lock1->lf_next = lock2;
|
|
}
|
|
|
|
/*
|
|
* Wakeup a blocklist
|
|
*/
|
|
static void
|
|
lf_wakelock(listhead)
|
|
struct lockf *listhead;
|
|
{
|
|
register struct lockf *wakelock;
|
|
|
|
while (wakelock = listhead->lf_blkhd.tqh_first) {
|
|
TAILQ_REMOVE(&listhead->lf_blkhd, wakelock, lf_block);
|
|
wakelock->lf_next = NOLOCKF;
|
|
#ifdef LOCKF_DEBUG
|
|
if (lockf_debug & 2)
|
|
lf_print("lf_wakelock: awakening", wakelock);
|
|
#endif /* LOCKF_DEBUG */
|
|
wakeup((caddr_t)wakelock);
|
|
}
|
|
}
|
|
|
|
#ifdef LOCKF_DEBUG
|
|
/*
|
|
* Print out a lock.
|
|
*/
|
|
void
|
|
lf_print(tag, lock)
|
|
char *tag;
|
|
register struct lockf *lock;
|
|
{
|
|
|
|
printf("%s: lock 0x%lx for ", tag, lock);
|
|
if (lock->lf_flags & F_POSIX)
|
|
printf("proc %d", ((struct proc *)(lock->lf_id))->p_pid);
|
|
else
|
|
printf("id 0x%x", lock->lf_id);
|
|
printf(" in ino %d on dev <%d, %d>, %s, start %d, end %d",
|
|
lock->lf_inode->i_number,
|
|
major(lock->lf_inode->i_dev),
|
|
minor(lock->lf_inode->i_dev),
|
|
lock->lf_type == F_RDLCK ? "shared" :
|
|
lock->lf_type == F_WRLCK ? "exclusive" :
|
|
lock->lf_type == F_UNLCK ? "unlock" :
|
|
"unknown", lock->lf_start, lock->lf_end);
|
|
if (lock->lf_blkhd.tqh_first)
|
|
printf(" block 0x%x\n", lock->lf_blkhd.tqh_first);
|
|
else
|
|
printf("\n");
|
|
}
|
|
|
|
void
|
|
lf_printlist(tag, lock)
|
|
char *tag;
|
|
struct lockf *lock;
|
|
{
|
|
register struct lockf *lf, *blk;
|
|
|
|
printf("%s: Lock list for ino %d on dev <%d, %d>:\n",
|
|
tag, lock->lf_inode->i_number,
|
|
major(lock->lf_inode->i_dev),
|
|
minor(lock->lf_inode->i_dev));
|
|
for (lf = lock->lf_inode->i_lockf; lf; lf = lf->lf_next) {
|
|
printf("\tlock 0x%lx for ", lf);
|
|
if (lf->lf_flags & F_POSIX)
|
|
printf("proc %d", ((struct proc *)(lf->lf_id))->p_pid);
|
|
else
|
|
printf("id 0x%x", lf->lf_id);
|
|
printf(", %s, start %d, end %d",
|
|
lf->lf_type == F_RDLCK ? "shared" :
|
|
lf->lf_type == F_WRLCK ? "exclusive" :
|
|
lf->lf_type == F_UNLCK ? "unlock" :
|
|
"unknown", lf->lf_start, lf->lf_end);
|
|
for (blk = lf->lf_blkhd.tqh_first; blk;
|
|
blk = blk->lf_block.tqe_next) {
|
|
printf("\n\t\tlock request 0x%lx for ", blk);
|
|
if (blk->lf_flags & F_POSIX)
|
|
printf("proc %d",
|
|
((struct proc *)(blk->lf_id))->p_pid);
|
|
else
|
|
printf("id 0x%x", blk->lf_id);
|
|
printf(", %s, start %d, end %d",
|
|
blk->lf_type == F_RDLCK ? "shared" :
|
|
blk->lf_type == F_WRLCK ? "exclusive" :
|
|
blk->lf_type == F_UNLCK ? "unlock" :
|
|
"unknown", blk->lf_start, blk->lf_end);
|
|
if (blk->lf_blkhd.tqh_first)
|
|
panic("lf_printlist: bad list");
|
|
}
|
|
printf("\n");
|
|
}
|
|
}
|
|
#endif /* LOCKF_DEBUG */
|