pcb.h revision 256281 
1/*-
2 * Copyright (c) 2003 Peter Wemm.
3 * Copyright (c) 1990 The Regents of the University of California.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * William Jolitz.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	from: @(#)pcb.h	5.10 (Berkeley) 5/12/91
34 * $FreeBSD: stable/10/sys/amd64/include/pcb.h 250423 2013-05-09 21:42:43Z dchagin $
35 */
36
37#ifndef _AMD64_PCB_H_
38#define _AMD64_PCB_H_
39
40/*
41 * AMD64 process control block
42 */
43#include <machine/fpu.h>
44#include <machine/segments.h>
45
46struct pcb {
47	register_t	pcb_r15;
48	register_t	pcb_r14;
49	register_t	pcb_r13;
50	register_t	pcb_r12;
51	register_t	pcb_rbp;
52	register_t	pcb_rsp;
53	register_t	pcb_rbx;
54	register_t	pcb_rip;
55	register_t	pcb_fsbase;
56	register_t	pcb_gsbase;
57	register_t	pcb_kgsbase;
58	register_t	pcb_cr0;
59	register_t	pcb_cr2;
60	register_t	pcb_cr3;
61	register_t	pcb_cr4;
62	register_t	pcb_dr0;
63	register_t	pcb_dr1;
64	register_t	pcb_dr2;
65	register_t	pcb_dr3;
66	register_t	pcb_dr6;
67	register_t	pcb_dr7;
68
69	struct region_descriptor pcb_gdt;
70	struct region_descriptor pcb_idt;
71	struct region_descriptor pcb_ldt;
72	uint16_t	pcb_tr;
73
74	u_int		pcb_flags;
75#define	PCB_FULL_IRET	0x01	/* full iret is required */
76#define	PCB_DBREGS	0x02	/* process using debug registers */
77#define	PCB_KERNFPU	0x04	/* kernel uses fpu */
78#define	PCB_FPUINITDONE	0x08	/* fpu state is initialized */
79#define	PCB_USERFPUINITDONE 0x10 /* fpu user state is initialized */
80#define	PCB_32BIT	0x40	/* process has 32 bit context (segs etc) */
81
82	uint16_t	pcb_initial_fpucw;
83
84	/* copyin/out fault recovery */
85	caddr_t		pcb_onfault;
86
87	/* 32-bit segment descriptor */
88	struct user_segment_descriptor pcb_gs32sd;
89
90	/* local tss, with i/o bitmap; NULL for common */
91	struct amd64tss *pcb_tssp;
92
93	/* model specific registers */
94	register_t	pcb_efer;
95	register_t	pcb_star;
96	register_t	pcb_lstar;
97	register_t	pcb_cstar;
98	register_t	pcb_sfmask;
99	register_t	pcb_xsmask;
100
101	/* fpu context for suspend/resume */
102	void		*pcb_fpususpend;
103
104	struct savefpu	*pcb_save;
105
106	uint64_t	pcb_pad[3];
107};
108
109#ifdef _KERNEL
110struct trapframe;
111
112/*
113 * The pcb_flags is only modified by current thread, or by other threads
114 * when current thread is stopped.  However, current thread may change it
115 * from the interrupt context in cpu_switch(), or in the trap handler.
116 * When we read-modify-write pcb_flags from C sources, compiler may generate
117 * code that is not atomic regarding the interrupt handler.  If a trap or
118 * interrupt happens and any flag is modified from the handler, it can be
119 * clobbered with the cached value later.  Therefore, we implement setting
120 * and clearing flags with single-instruction functions, which do not race
121 * with possible modification of the flags from the trap or interrupt context,
122 * because traps and interrupts are executed only on instruction boundary.
123 */
124static __inline void
125set_pcb_flags(struct pcb *pcb, const u_int flags)
126{
127
128	__asm __volatile("orl %1,%0"
129	    : "=m" (pcb->pcb_flags) : "ir" (flags), "m" (pcb->pcb_flags)
130	    : "cc");
131}
132
133static __inline void
134clear_pcb_flags(struct pcb *pcb, const u_int flags)
135{
136
137	__asm __volatile("andl %1,%0"
138	    : "=m" (pcb->pcb_flags) : "ir" (~flags), "m" (pcb->pcb_flags)
139	    : "cc");
140}
141
142void	makectx(struct trapframe *, struct pcb *);
143int	savectx(struct pcb *) __returns_twice;
144void	resumectx(struct pcb *);
145
146#endif
147
148#endif /* _AMD64_PCB_H_ */
149