xref: /netbsd-src/sys/arch/amd64/include/frameasm.h (revision ebc1f703f93bf8e74b4e8cc4d945280f1a3a7edc)
1 /*	$NetBSD: frameasm.h,v 1.35 2018/02/22 08:56:51 maxv Exp $	*/
2 
3 #ifndef _AMD64_MACHINE_FRAMEASM_H
4 #define _AMD64_MACHINE_FRAMEASM_H
5 
6 #ifdef _KERNEL_OPT
7 #include "opt_xen.h"
8 #include "opt_svs.h"
9 #endif
10 
11 /*
12  * Macros to define pushing/popping frames for interrupts, traps
13  * and system calls. Currently all the same; will diverge later.
14  */
15 
16 #ifdef XEN
17 #define HYPERVISOR_iret hypercall_page + (__HYPERVISOR_iret * 32)
18 /* Xen do not need swapgs, done by hypervisor */
19 #define swapgs
20 #define iretq	pushq $0 ; jmp HYPERVISOR_iret
21 #define	XEN_ONLY2(x,y)	x,y
22 #define	NOT_XEN(x)
23 
24 #define CLI(temp_reg) \
25  	movq CPUVAR(VCPU),%r ## temp_reg ;			\
26 	movb $1,EVTCHN_UPCALL_MASK(%r ## temp_reg);
27 
28 #define STI(temp_reg) \
29  	movq CPUVAR(VCPU),%r ## temp_reg ;			\
30 	movb $0,EVTCHN_UPCALL_MASK(%r ## temp_reg);
31 
32 #else /* XEN */
33 #define	XEN_ONLY2(x,y)
34 #define	NOT_XEN(x)	x
35 #define CLI(temp_reg) cli
36 #define STI(temp_reg) sti
37 #endif	/* XEN */
38 
39 #define HP_NAME_CLAC		1
40 #define HP_NAME_STAC		2
41 #define HP_NAME_NOLOCK		3
42 #define HP_NAME_RETFENCE	4
43 #define HP_NAME_SVS_ENTER	5
44 #define HP_NAME_SVS_LEAVE	6
45 #define HP_NAME_SVS_ENTER_ALT	7
46 #define HP_NAME_SVS_LEAVE_ALT	8
47 
48 #define HOTPATCH(name, size) \
49 123:						; \
50 	.pushsection	.rodata.hotpatch, "a"	; \
51 	.byte		name			; \
52 	.byte		size			; \
53 	.quad		123b			; \
54 	.popsection
55 
56 #define SMAP_ENABLE \
57 	HOTPATCH(HP_NAME_CLAC, 3)		; \
58 	.byte 0x0F, 0x1F, 0x00			; \
59 
60 #define SMAP_DISABLE \
61 	HOTPATCH(HP_NAME_STAC, 3)		; \
62 	.byte 0x0F, 0x1F, 0x00			; \
63 
64 #define	SWAPGS	NOT_XEN(swapgs)
65 
66 /*
67  * These are used on interrupt or trap entry or exit.
68  */
69 #define INTR_SAVE_GPRS \
70 	movq	%rdi,TF_RDI(%rsp)	; \
71 	movq	%rsi,TF_RSI(%rsp)	; \
72 	movq	%rdx,TF_RDX(%rsp)	; \
73 	movq	%rcx,TF_RCX(%rsp)	; \
74 	movq	%r8,TF_R8(%rsp)		; \
75 	movq	%r9,TF_R9(%rsp)		; \
76 	movq	%r10,TF_R10(%rsp)	; \
77 	movq	%r11,TF_R11(%rsp)	; \
78 	movq	%r12,TF_R12(%rsp)	; \
79 	movq	%r13,TF_R13(%rsp)	; \
80 	movq	%r14,TF_R14(%rsp)	; \
81 	movq	%r15,TF_R15(%rsp)	; \
82 	movq	%rbp,TF_RBP(%rsp)	; \
83 	movq	%rbx,TF_RBX(%rsp)	; \
84 	movq	%rax,TF_RAX(%rsp)
85 
86 #define	INTR_RESTORE_GPRS \
87 	movq	TF_RDI(%rsp),%rdi	; \
88 	movq	TF_RSI(%rsp),%rsi	; \
89 	movq	TF_RDX(%rsp),%rdx	; \
90 	movq	TF_RCX(%rsp),%rcx	; \
91 	movq	TF_R8(%rsp),%r8		; \
92 	movq	TF_R9(%rsp),%r9		; \
93 	movq	TF_R10(%rsp),%r10	; \
94 	movq	TF_R11(%rsp),%r11	; \
95 	movq	TF_R12(%rsp),%r12	; \
96 	movq	TF_R13(%rsp),%r13	; \
97 	movq	TF_R14(%rsp),%r14	; \
98 	movq	TF_R15(%rsp),%r15	; \
99 	movq	TF_RBP(%rsp),%rbp	; \
100 	movq	TF_RBX(%rsp),%rbx	; \
101 	movq	TF_RAX(%rsp),%rax
102 
103 #define TEXT_USER_BEGIN	.pushsection	.text.user, "ax"
104 #define TEXT_USER_END	.popsection
105 
106 #ifdef SVS
107 
108 /* XXX: put this somewhere else */
109 #define SVS_UTLS		0xffffc00000000000 /* PMAP_PCPU_BASE */
110 #define UTLS_KPDIRPA		0
111 #define UTLS_SCRATCH		8
112 #define UTLS_RSP0		16
113 
114 #define SVS_ENTER_BYTES	22
115 #define SVS_ENTER \
116 	HOTPATCH(HP_NAME_SVS_ENTER, SVS_ENTER_BYTES)	; \
117 	.byte 0xEB, (SVS_ENTER_BYTES-2)	/* jmp */	; \
118 	.fill	(SVS_ENTER_BYTES-2),1,0xCC
119 
120 #define SVS_LEAVE_BYTES	31
121 #define SVS_LEAVE \
122 	HOTPATCH(HP_NAME_SVS_LEAVE, SVS_LEAVE_BYTES)	; \
123 	.byte 0xEB, (SVS_LEAVE_BYTES-2)	/* jmp */	; \
124 	.fill	(SVS_LEAVE_BYTES-2),1,0xCC
125 
126 #define SVS_ENTER_ALT_BYTES	23
127 #define SVS_ENTER_ALTSTACK \
128 	HOTPATCH(HP_NAME_SVS_ENTER_ALT, SVS_ENTER_ALT_BYTES)	; \
129 	.byte 0xEB, (SVS_ENTER_ALT_BYTES-2)	/* jmp */	; \
130 	.fill	(SVS_ENTER_ALT_BYTES-2),1,0xCC
131 
132 #define SVS_LEAVE_ALT_BYTES	22
133 #define SVS_LEAVE_ALTSTACK \
134 	HOTPATCH(HP_NAME_SVS_LEAVE_ALT, SVS_LEAVE_ALT_BYTES)	; \
135 	.byte 0xEB, (SVS_LEAVE_ALT_BYTES-2)	/* jmp */	; \
136 	.fill	(SVS_LEAVE_ALT_BYTES-2),1,0xCC
137 
138 #else
139 #define SVS_ENTER	/* nothing */
140 #define SVS_LEAVE	/* nothing */
141 #define SVS_ENTER_ALTSTACK	/* nothing */
142 #define SVS_LEAVE_ALTSTACK	/* nothing */
143 #endif
144 
145 #define	INTRENTRY_L(kernel_trap, usertrap) \
146 	subq	$TF_REGSIZE,%rsp	; \
147 	INTR_SAVE_GPRS			; \
148 	cld				; \
149 	SMAP_ENABLE			; \
150 	testb	$SEL_UPL,TF_CS(%rsp)	; \
151 	je	kernel_trap		; \
152 usertrap				; \
153 	SWAPGS				; \
154 	SVS_ENTER			; \
155 	movw	%gs,TF_GS(%rsp)		; \
156 	movw	%fs,TF_FS(%rsp)		; \
157 	movw	%es,TF_ES(%rsp)		; \
158 	movw	%ds,TF_DS(%rsp)
159 
160 #define	INTRENTRY \
161 	INTRENTRY_L(98f,)		; \
162 98:
163 
164 #define INTRFASTEXIT \
165 	jmp	intrfastexit
166 
167 #define INTR_RECURSE_HWFRAME \
168 	movq	%rsp,%r10		; \
169 	movl	%ss,%r11d		; \
170 	pushq	%r11			; \
171 	pushq	%r10			; \
172 	pushfq				; \
173 	pushq	$GSEL(GCODE_SEL,SEL_KPL); \
174 /* XEN: We must fixup CS, as even kernel mode runs at CPL 3 */ \
175  	XEN_ONLY2(andb	$0xfc,(%rsp);)	  \
176 	pushq	%r13			;
177 
178 #define INTR_RECURSE_ENTRY \
179 	subq	$TF_REGSIZE,%rsp	; \
180 	INTR_SAVE_GPRS			; \
181 	cld
182 
183 #define	CHECK_DEFERRED_SWITCH \
184 	cmpl	$0, CPUVAR(WANT_PMAPLOAD)
185 
186 #define CHECK_ASTPENDING(reg)	cmpl	$0, L_MD_ASTPENDING(reg)
187 #define CLEAR_ASTPENDING(reg)	movl	$0, L_MD_ASTPENDING(reg)
188 
189 #endif /* _AMD64_MACHINE_FRAMEASM_H */
190