1139825Simp/*- 21960Sdg * Copyright (c) 1991, 1993 31960Sdg * The Regents of the University of California. All rights reserved. 41960Sdg * 51960Sdg * This code is derived from software contributed to Berkeley by 61960Sdg * Scooter Morris at Genentech Inc. 71960Sdg * 81960Sdg * Redistribution and use in source and binary forms, with or without 91960Sdg * modification, are permitted provided that the following conditions 101960Sdg * are met: 111960Sdg * 1. Redistributions of source code must retain the above copyright 121960Sdg * notice, this list of conditions and the following disclaimer. 131960Sdg * 2. Redistributions in binary form must reproduce the above copyright 141960Sdg * notice, this list of conditions and the following disclaimer in the 151960Sdg * documentation and/or other materials provided with the distribution. 161960Sdg * 4. Neither the name of the University nor the names of its contributors 171960Sdg * may be used to endorse or promote products derived from this software 181960Sdg * without specific prior written permission. 191960Sdg * 201960Sdg * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 211960Sdg * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 221960Sdg * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 231960Sdg * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 241960Sdg * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 251960Sdg * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 261960Sdg * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 271960Sdg * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 281960Sdg * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 291960Sdg * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 301960Sdg * SUCH DAMAGE. 311960Sdg * 321960Sdg * @(#)lockf.h 8.1 (Berkeley) 6/11/93 3350477Speter * $FreeBSD: releng/10.3/sys/sys/lockf.h 192685 2009-05-24 12:39:38Z kib $ 341960Sdg */ 351960Sdg 362165Spaul#ifndef _SYS_LOCKF_H_ 3715493Sbde#define _SYS_LOCKF_H_ 382165Spaul 3933057Sbde#include <sys/queue.h> 40177633Sdfr#include <sys/_lock.h> 41177633Sdfr#include <sys/_sx.h> 4233057Sbde 43180025Sdfrstruct flock; 4433057Sbdestruct vop_advlock_args; 45177633Sdfrstruct vop_advlockasync_args; 4633057Sbde 471960Sdg/* 48177633Sdfr * The lockf_entry structure is a kernel structure which contains the 49177633Sdfr * information associated with a byte range lock. The lockf_entry 50177633Sdfr * structures are linked into the inode structure. Locks are sorted by 51177633Sdfr * the starting byte of the lock for efficiency. 52177633Sdfr * 53177633Sdfr * Active and pending locks on a vnode are organised into a 54177633Sdfr * graph. Each pending lock has an out-going edge to each active lock 55177633Sdfr * that blocks it. 56177633Sdfr * 57177633Sdfr * Locks: 58177633Sdfr * (i) locked by the vnode interlock 59177633Sdfr * (s) locked by state->ls_lock 60177633Sdfr * (S) locked by lf_lock_states_lock 61177633Sdfr * (c) const until freeing 621960Sdg */ 63177633Sdfrstruct lockf_edge { 64177633Sdfr LIST_ENTRY(lockf_edge) le_outlink; /* (s) link from's out-edge list */ 65177633Sdfr LIST_ENTRY(lockf_edge) le_inlink; /* (s) link to's in-edge list */ 66177633Sdfr struct lockf_entry *le_from; /* (c) out-going from here */ 67177633Sdfr struct lockf_entry *le_to; /* (s) in-coming to here */ 68177633Sdfr}; 69177633SdfrLIST_HEAD(lockf_edge_list, lockf_edge); 7022521Sdyson 71177633Sdfrstruct lockf_entry { 72177633Sdfr short lf_flags; /* (c) Semantics: F_POSIX, F_FLOCK, F_WAIT */ 73177633Sdfr short lf_type; /* (s) Lock type: F_RDLCK, F_WRLCK */ 74177633Sdfr off_t lf_start; /* (s) Byte # of the start of the lock */ 75177633Sdfr off_t lf_end; /* (s) Byte # of the end of the lock (OFF_MAX=EOF) */ 76177633Sdfr struct lock_owner *lf_owner; /* (c) Owner of the lock */ 77177633Sdfr struct vnode *lf_vnode; /* (c) File being locked (only valid for active lock) */ 78177633Sdfr struct inode *lf_inode; /* (c) Back pointer to the inode */ 79177633Sdfr struct task *lf_async_task;/* (c) Async lock callback */ 80177633Sdfr LIST_ENTRY(lockf_entry) lf_link; /* (s) Linkage for lock lists */ 81177633Sdfr struct lockf_edge_list lf_outedges; /* (s) list of out-edges */ 82177633Sdfr struct lockf_edge_list lf_inedges; /* (s) list of out-edges */ 83192685Skib int lf_refs; /* (s) ref count */ 84177633Sdfr}; 85177633SdfrLIST_HEAD(lockf_entry_list, lockf_entry); 86177633Sdfr 87177633Sdfr/* 88178243Skib * Extra lf_flags bits used by the implementation 89178243Skib */ 90178243Skib#define F_INTR 0x8000 /* lock was interrupted by lf_purgelocks */ 91178243Skib 92178243Skib/* 93177633Sdfr * Filesystem private node structures should include space for a 94177633Sdfr * pointer to a struct lockf_state. This pointer is used by the lock 95177633Sdfr * manager to track the locking state for a file. 96177633Sdfr * 97177633Sdfr * The ls_active list contains the set of active locks on the file. It 98177633Sdfr * is strictly ordered by the lock's lf_start value. Each active lock 99177633Sdfr * will have in-coming edges to any pending lock which it blocks. 100177633Sdfr * 101177633Sdfr * Lock requests which are blocked by some other active lock are 102177633Sdfr * listed in ls_pending with newer requests first in the list. Lock 103177633Sdfr * requests in this list will have out-going edges to each active lock 104177633Sdfr * that blocks then. They will also have out-going edges to each 105177633Sdfr * pending lock that is older in the queue - this helps to ensure 106177633Sdfr * fairness when several processes are contenting to lock the same 107177633Sdfr * record. 108177633Sdfr 109177633Sdfr * The value of ls_threads is the number of threads currently using 110177633Sdfr * the state structure (typically either setting/clearing locks or 111177633Sdfr * sleeping waiting to do so). This is used to defer freeing the 112177633Sdfr * structure while some thread is still using it. 113177633Sdfr */ 1141960Sdgstruct lockf { 115177633Sdfr LIST_ENTRY(lockf) ls_link; /* (S) all active lockf states */ 116177633Sdfr struct sx ls_lock; 117177633Sdfr struct lockf_entry_list ls_active; /* (s) Active locks */ 118177633Sdfr struct lockf_entry_list ls_pending; /* (s) Pending locks */ 119177633Sdfr int ls_threads; /* (i) Thread count */ 1201960Sdg}; 121177633SdfrLIST_HEAD(lockf_list, lockf); 1221960Sdg 123180025Sdfrtypedef int lf_iterator(struct vnode *, struct flock *, void *); 124180025Sdfr 12592719Salfredint lf_advlock(struct vop_advlock_args *, struct lockf **, u_quad_t); 126177633Sdfrint lf_advlockasync(struct vop_advlockasync_args *, struct lockf **, u_quad_t); 127178243Skibvoid lf_purgelocks(struct vnode *vp, struct lockf **statep); 128180025Sdfrint lf_iteratelocks_sysid(int sysid, lf_iterator *, void *); 129180025Sdfrint lf_iteratelocks_vnode(struct vnode *vp, lf_iterator *, void *); 130177633Sdfrint lf_countlocks(int sysid); 131177633Sdfrvoid lf_clearremotesys(int sysid); 1321960Sdg 13315493Sbde#endif /* !_SYS_LOCKF_H_ */ 134