X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/5d5c5d0d5b79ade9a973d55186ffda2638ba2b6e..d190cdc3f5544636abb56dc1874be391d3e1b148:/bsd/sys/lock.h diff --git a/bsd/sys/lock.h b/bsd/sys/lock.h index bfed673aa..4e2c537dc 100644 --- a/bsd/sys/lock.h +++ b/bsd/sys/lock.h @@ -1,31 +1,29 @@ /* - * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved. * - * @APPLE_LICENSE_OSREFERENCE_HEADER_START@ + * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * - * This file contains Original Code and/or Modifications of Original Code - * as defined in and that are subject to the Apple Public Source License - * Version 2.0 (the 'License'). You may not use this file except in - * compliance with the License. The rights granted to you under the - * License may not be used to create, or enable the creation or - * redistribution of, unlawful or unlicensed copies of an Apple operating - * system, or to circumvent, violate, or enable the circumvention or - * violation of, any terms of an Apple operating system software license - * agreement. - * - * Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this - * file. - * - * The Original Code and all software distributed under the License are - * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER - * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, - * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. - * Please see the License for the specific language governing rights and + * This file contains Original Code and/or Modifications of Original Code + * as defined in and that are subject to the Apple Public Source License + * Version 2.0 (the 'License'). You may not use this file except in + * compliance with the License. The rights granted to you under the License + * may not be used to create, or enable the creation or redistribution of, + * unlawful or unlicensed copies of an Apple operating system, or to + * circumvent, violate, or enable the circumvention or violation of, any + * terms of an Apple operating system software license agreement. + * + * Please obtain a copy of the License at + * http://www.opensource.apple.com/apsl/ and read it before using this file. + * + * The Original Code and all software distributed under the License are + * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER + * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, + * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. + * Please see the License for the specific language governing rights and * limitations under the License. - * - * @APPLE_LICENSE_OSREFERENCE_HEADER_END@ + * + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* Copyright (c) 1995, 1997 Apple Computer, Inc. All Rights Reserved */ /* @@ -80,149 +78,4 @@ #endif /* KERNEL */ -#ifdef BSD_KERNEL_PRIVATE -/* - * The general lock structure. Provides for multiple shared locks, - * upgrading from shared to exclusive, and sleeping until the lock - * can be gained. The simple locks are defined in . - */ -struct lock__bsd__ { - void * lk_interlock[10]; /* lock on remaining fields */ - u_int lk_flags; /* see below */ - int lk_sharecount; /* # of accepted shared locks */ - int lk_waitcount; /* # of processes sleeping for lock */ - short lk_exclusivecount; /* # of recursive exclusive locks */ - short lk_prio; /* priority at which to sleep */ - const char *lk_wmesg; /* resource sleeping (for tsleep) */ - int lk_timo; /* maximum sleep time (for tsleep) */ - pid_t lk_lockholder; /* pid of exclusive lock holder */ - void *lk_lockthread; /* thread which acquired excl lock */ -}; - -// LP64todo - should this move? - -/* LP64 version of lock__bsd__. all pointers - * grow when we're dealing with a 64-bit process. - * WARNING - keep in sync with lock__bsd__ - */ - -struct user_lock__bsd__ { - user_addr_t lk_interlock[10]; /* lock on remaining fields */ - u_int lk_flags; /* see below */ - int lk_sharecount; /* # of accepted shared locks */ - int lk_waitcount; /* # of processes sleeping for lock */ - short lk_exclusivecount; /* # of recursive exclusive locks */ - short lk_prio; /* priority at which to sleep */ - user_addr_t lk_wmesg; /* resource sleeping (for tsleep) */ - int lk_timo; /* maximum sleep time (for tsleep) */ - pid_t lk_lockholder; /* pid of exclusive lock holder */ - user_addr_t lk_lockthread; /* thread which acquired excl lock */ -}; - -/* - * Lock request types: - * LK_SHARED - get one of many possible shared locks. If a process - * holding an exclusive lock requests a shared lock, the exclusive - * lock(s) will be downgraded to shared locks. - * LK_EXCLUSIVE - stop further shared locks, when they are cleared, - * grant a pending upgrade if it exists, then grant an exclusive - * lock. Only one exclusive lock may exist at a time, except that - * a process holding an exclusive lock may get additional exclusive - * locks if it explicitly sets the LK_CANRECURSE flag in the lock - * request, or if the LK_CANRECUSE flag was set when the lock was - * initialized. - * LK_UPGRADE - the process must hold a shared lock that it wants to - * have upgraded to an exclusive lock. Other processes may get - * exclusive access to the resource between the time that the upgrade - * is requested and the time that it is granted. - * LK_EXCLUPGRADE - the process must hold a shared lock that it wants to - * have upgraded to an exclusive lock. If the request succeeds, no - * other processes will have gotten exclusive access to the resource - * between the time that the upgrade is requested and the time that - * it is granted. However, if another process has already requested - * an upgrade, the request will fail (see error returns below). - * LK_DOWNGRADE - the process must hold an exclusive lock that it wants - * to have downgraded to a shared lock. If the process holds multiple - * (recursive) exclusive locks, they will all be downgraded to shared - * locks. - * LK_RELEASE - release one instance of a lock. - * LK_DRAIN - wait for all activity on the lock to end, then mark it - * decommissioned. This feature is used before freeing a lock that - * is part of a piece of memory that is about to be freed. - * - * These are flags that are passed to the lockmgr routine. - */ -#define LK_TYPE_MASK 0x0000000f /* type of lock sought */ -#define LK_SHARED 0x00000001 /* shared lock */ -#define LK_EXCLUSIVE 0x00000002 /* exclusive lock */ -#define LK_UPGRADE 0x00000003 /* shared-to-exclusive upgrade */ -#define LK_EXCLUPGRADE 0x00000004 /* first shared-to-exclusive upgrade */ -#define LK_DOWNGRADE 0x00000005 /* exclusive-to-shared downgrade */ -#define LK_RELEASE 0x00000006 /* release any type of lock */ -#define LK_DRAIN 0x00000007 /* wait for all lock activity to end */ -/* - * External lock flags. - * - * The first three flags may be set in lock_init to set their mode permanently, - * or passed in as arguments to the lock manager. The LK_REENABLE flag may be - * set only at the release of a lock obtained by drain. - */ -#define LK_EXTFLG_MASK 0x00000070 /* mask of external flags */ -#define LK_NOWAIT 0x00000010 /* do not sleep to await lock */ -#define LK_SLEEPFAIL 0x00000020 /* sleep, then return failure */ -#define LK_CANRECURSE 0x00000040 /* allow recursive exclusive lock */ -#define LK_REENABLE 0x00000080 /* lock is be reenabled after drain */ -/* - * Internal lock flags. - * - * These flags are used internally to the lock manager. - */ -#define LK_WANT_UPGRADE 0x00000100 /* waiting for share-to-excl upgrade */ -#define LK_WANT_EXCL 0x00000200 /* exclusive lock sought */ -#define LK_HAVE_EXCL 0x00000400 /* exclusive lock obtained */ -#define LK_WAITDRAIN 0x00000800 /* process waiting for lock to drain */ -#define LK_DRAINING 0x00004000 /* lock is being drained */ -#define LK_DRAINED 0x00008000 /* lock has been decommissioned */ -/* - * Control flags - * - * Non-persistent external flags. - */ -#define LK_INTERLOCK 0x00010000 /* unlock passed simple lock after - getting lk_interlock */ -#define LK_RETRY 0x00020000 /* vn_lock: retry until locked */ - -/* - * Lock return status. - * - * Successfully obtained locks return 0. Locks will always succeed - * unless one of the following is true: - * LK_FORCEUPGRADE is requested and some other process has already - * requested a lock upgrade (returns EBUSY). - * LK_WAIT is set and a sleep would be required (returns EBUSY). - * LK_SLEEPFAIL is set and a sleep was done (returns ENOLCK). - * PCATCH is set in lock priority and a signal arrives (returns - * either EINTR or ERESTART if system calls is to be restarted). - * Non-null lock timeout and timeout expires (returns EWOULDBLOCK). - * A failed lock attempt always returns a non-zero error value. No lock - * is held after an error return (in particular, a failed LK_UPGRADE - * or LK_FORCEUPGRADE will have released its shared access lock). - */ - -/* - * Indicator that no process holds exclusive lock - */ -#define LK_KERNPROC ((pid_t) -2) -#define LK_NOPROC ((pid_t) -1) - -struct proc; - -void lockinit(struct lock__bsd__ *, int prio, const char *wmesg, int timo, - int flags); -int lockmgr(struct lock__bsd__ *, u_int flags, - void *, struct proc *p); -int lockstatus(struct lock__bsd__ *); - -#endif /* BSD_KERNEL_PRIVATE */ - #endif /* _SYS_LOCK_H_ */