xref: /freebsd/sys/amd64/include/pcb.h (revision 640235e2c2ba32947f7c59d168437ffa1280f1e6)
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  * $FreeBSD$
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 
46 #ifdef __amd64__
47 /*
48  * NB: The fields marked with (*) are used by kernel debuggers.  Their
49  * ABI should be preserved.
50  */
51 struct pcb {
52 	register_t	pcb_r15;	/* (*) */
53 	register_t	pcb_r14;	/* (*) */
54 	register_t	pcb_r13;	/* (*) */
55 	register_t	pcb_r12;	/* (*) */
56 	register_t	pcb_rbp;	/* (*) */
57 	register_t	pcb_rsp;	/* (*) */
58 	register_t	pcb_rbx;	/* (*) */
59 	register_t	pcb_rip;	/* (*) */
60 	register_t	pcb_fsbase;
61 	register_t	pcb_gsbase;
62 	register_t	pcb_kgsbase;
63 	register_t	pcb_cr0;
64 	register_t	pcb_cr2;
65 	register_t	pcb_cr3;
66 	register_t	pcb_cr4;
67 	register_t	pcb_dr0;
68 	register_t	pcb_dr1;
69 	register_t	pcb_dr2;
70 	register_t	pcb_dr3;
71 	register_t	pcb_dr6;
72 	register_t	pcb_dr7;
73 
74 	struct region_descriptor pcb_gdt;
75 	struct region_descriptor pcb_idt;
76 	struct region_descriptor pcb_ldt;
77 	uint16_t	pcb_tr;
78 
79 	u_int		pcb_flags;
80 #define	PCB_FULL_IRET	0x01	/* full iret is required */
81 #define	PCB_DBREGS	0x02	/* process using debug registers */
82 #define	PCB_KERNFPU	0x04	/* kernel uses fpu */
83 #define	PCB_FPUINITDONE	0x08	/* fpu state is initialized */
84 #define	PCB_USERFPUINITDONE 0x10 /* fpu user state is initialized */
85 #define	PCB_32BIT	0x40	/* process has 32 bit context (segs etc) */
86 
87 	uint16_t	pcb_initial_fpucw;
88 
89 	/* copyin/out fault recovery */
90 	caddr_t		pcb_onfault;
91 
92 	uint64_t	pcb_pad0;
93 
94 	/* local tss, with i/o bitmap; NULL for common */
95 	struct amd64tss *pcb_tssp;
96 
97 	/* model specific registers */
98 	register_t	pcb_efer;
99 	register_t	pcb_star;
100 	register_t	pcb_lstar;
101 	register_t	pcb_cstar;
102 	register_t	pcb_sfmask;
103 
104 	struct savefpu	*pcb_save;
105 
106 	uint64_t	pcb_pad[5];
107 };
108 
109 /* Per-CPU state saved during suspend and resume. */
110 struct susppcb {
111 	struct pcb	sp_pcb;
112 
113 	/* fpu context for suspend/resume */
114 	void		*sp_fpususpend;
115 };
116 #endif
117 
118 #ifdef _KERNEL
119 struct trapframe;
120 
121 /*
122  * The pcb_flags is only modified by current thread, or by other threads
123  * when current thread is stopped.  However, current thread may change it
124  * from the interrupt context in cpu_switch(), or in the trap handler.
125  * When we read-modify-write pcb_flags from C sources, compiler may generate
126  * code that is not atomic regarding the interrupt handler.  If a trap or
127  * interrupt happens and any flag is modified from the handler, it can be
128  * clobbered with the cached value later.  Therefore, we implement setting
129  * and clearing flags with single-instruction functions, which do not race
130  * with possible modification of the flags from the trap or interrupt context,
131  * because traps and interrupts are executed only on instruction boundary.
132  */
133 static __inline void
134 set_pcb_flags(struct pcb *pcb, const u_int flags)
135 {
136 
137 	__asm __volatile("orl %1,%0"
138 	    : "=m" (pcb->pcb_flags) : "ir" (flags), "m" (pcb->pcb_flags)
139 	    : "cc");
140 }
141 
142 static __inline void
143 clear_pcb_flags(struct pcb *pcb, const u_int flags)
144 {
145 
146 	__asm __volatile("andl %1,%0"
147 	    : "=m" (pcb->pcb_flags) : "ir" (~flags), "m" (pcb->pcb_flags)
148 	    : "cc");
149 }
150 
151 void	makectx(struct trapframe *, struct pcb *);
152 int	savectx(struct pcb *) __returns_twice;
153 void	resumectx(struct pcb *);
154 
155 #endif
156 
157 #endif /* _AMD64_PCB_H_ */
158