/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * William Jolitz. * * 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. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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. */ #ifndef _MACHINE_PSL_H_ #define _MACHINE_PSL_H_ /* * 386 processor status longword. */ #define PSL_C 0x00000001 /* carry bit */ #define PSL_PF 0x00000004 /* parity bit */ #define PSL_AF 0x00000010 /* bcd carry bit */ #define PSL_Z 0x00000040 /* zero bit */ #define PSL_N 0x00000080 /* negative bit */ #define PSL_T 0x00000100 /* trace enable bit */ #define PSL_I 0x00000200 /* interrupt enable bit */ #define PSL_D 0x00000400 /* string instruction direction bit */ #define PSL_V 0x00000800 /* overflow bit */ #define PSL_IOPL 0x00003000 /* i/o privilege level */ #define PSL_NT 0x00004000 /* nested task bit */ #define PSL_RF 0x00010000 /* resume flag bit */ #define PSL_VM 0x00020000 /* virtual 8086 mode bit */ #define PSL_AC 0x00040000 /* alignment checking */ #define PSL_VIF 0x00080000 /* virtual interrupt enable */ #define PSL_VIP 0x00100000 /* virtual interrupt pending */ #define PSL_ID 0x00200000 /* identification bit */ /* * The i486 manual says that we are not supposed to change reserved flags, * but this is too much trouble since the reserved flags depend on the cpu * and setting them to their historical values works in practice. */ #define PSL_RESERVED_DEFAULT 0x00000002 /* * Initial flags for kernel and user mode. The kernel later inherits * PSL_I and some other flags from user mode. */ #define PSL_KERNEL PSL_RESERVED_DEFAULT #define PSL_USER (PSL_RESERVED_DEFAULT | PSL_I) /* * Bits that can be changed in user mode on 486's. We allow these bits * to be changed using ptrace(), sigreturn() and procfs. Setting PS_NT * is undesirable but it may as well be allowed since users can inflict * it on the kernel directly. Changes to PSL_AC are silently ignored on * 386's. * * Users are allowed to change the privileged flag PSL_RF. The cpu sets PSL_RF * in tf_eflags for faults. Debuggers should sometimes set it there too. * tf_eflags is kept in the signal context during signal handling and there is * no other place to remember it, so the PSL_RF bit may be corrupted by the * signal handler without us knowing. Corruption of the PSL_RF bit at worst * causes one more or one less debugger trap, so allowing it is fairly * harmless. */ #define PSL_USERCHANGE (PSL_C | PSL_PF | PSL_AF | PSL_Z | PSL_N | PSL_T \ | PSL_D | PSL_V | PSL_NT | PSL_RF | PSL_AC | PSL_ID) #endif /* !_MACHINE_PSL_H_ */
