freebsd-skq/sys/amd64/include/pcb.h
peter 12d7e4bee6 Collect the nastiness for preserving the kernel MSR_GSBASE around the
load_gs() calls into a single place that is less likely to go wrong.

Eliminate the per-process context switching of MSR_GSBASE, because it
should be constant for a single cpu.  Instead, save/restore it during
the loading of the new %gs selector for the new process.

Approved by:	re (amd64/* blanket)
2003-05-15 00:23:40 +00:00

81 lines
2.7 KiB
C

/*-
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* from: @(#)pcb.h 5.10 (Berkeley) 5/12/91
* $FreeBSD$
*/
#ifndef _I386_PCB_H_
#define _I386_PCB_H_
/*
* Intel 386 process control block
*/
#include <machine/npx.h>
struct pcb {
register_t padxx[8];
register_t pcb_cr3;
register_t pcb_r15;
register_t pcb_r14;
register_t pcb_r13;
register_t pcb_r12;
register_t pcb_rbp;
register_t pcb_rsp;
register_t pcb_rbx;
register_t pcb_rip;
register_t pcb_rflags;
register_t pcb_fsbase;
register_t pcb_gsbase;
u_int32_t pcb_ds;
u_int32_t pcb_es;
u_int32_t pcb_fs;
u_int32_t pcb_gs;
struct savefpu pcb_save;
u_long pcb_flags;
#define PCB_NPXTRAP 0x01 /* npx trap pending */
#define PCB_NPXINITDONE 0x02 /* fpu state is initialized */
#define PCB_FULLCTX 0x04 /* full context restore on sysret */
caddr_t pcb_onfault; /* copyin/out fault recovery */
};
#ifdef _KERNEL
void savectx(struct pcb *);
#endif
#endif /* _I386_PCB_H_ */