xref: /netbsd-src/sys/arch/amd64/include/frameasm.h (revision c38e7cc395b1472a774ff828e46123de44c628e9)
1 /*	$NetBSD: frameasm.h,v 1.38 2018/03/28 16:02:49 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 #define HP_NAME_IBRS_ENTER	9
48 #define HP_NAME_IBRS_LEAVE	10
49 
50 #define HOTPATCH(name, size) \
51 123:						; \
52 	.pushsection	.rodata.hotpatch, "a"	; \
53 	.byte		name			; \
54 	.byte		size			; \
55 	.quad		123b			; \
56 	.popsection
57 
58 #define SMAP_ENABLE \
59 	HOTPATCH(HP_NAME_CLAC, 3)		; \
60 	.byte 0x0F, 0x1F, 0x00			; \
61 
62 #define SMAP_DISABLE \
63 	HOTPATCH(HP_NAME_STAC, 3)		; \
64 	.byte 0x0F, 0x1F, 0x00			; \
65 
66 /*
67  * IBRS
68  */
69 
70 #define IBRS_ENTER_BYTES	17
71 #define IBRS_ENTER \
72 	HOTPATCH(HP_NAME_IBRS_ENTER, IBRS_ENTER_BYTES)		; \
73 	NOIBRS_ENTER
74 #define NOIBRS_ENTER \
75 	.byte 0xEB, (IBRS_ENTER_BYTES-2)	/* jmp */	; \
76 	.fill	(IBRS_ENTER_BYTES-2),1,0xCC
77 
78 #define IBRS_LEAVE_BYTES	21
79 #define IBRS_LEAVE \
80 	HOTPATCH(HP_NAME_IBRS_LEAVE, IBRS_LEAVE_BYTES)		; \
81 	NOIBRS_LEAVE
82 #define NOIBRS_LEAVE \
83 	.byte 0xEB, (IBRS_LEAVE_BYTES-2)	/* jmp */	; \
84 	.fill	(IBRS_LEAVE_BYTES-2),1,0xCC
85 
86 #define	SWAPGS	NOT_XEN(swapgs)
87 
88 /*
89  * These are used on interrupt or trap entry or exit.
90  */
91 #define INTR_SAVE_GPRS \
92 	movq	%rdi,TF_RDI(%rsp)	; \
93 	movq	%rsi,TF_RSI(%rsp)	; \
94 	movq	%rdx,TF_RDX(%rsp)	; \
95 	movq	%rcx,TF_RCX(%rsp)	; \
96 	movq	%r8,TF_R8(%rsp)		; \
97 	movq	%r9,TF_R9(%rsp)		; \
98 	movq	%r10,TF_R10(%rsp)	; \
99 	movq	%r11,TF_R11(%rsp)	; \
100 	movq	%r12,TF_R12(%rsp)	; \
101 	movq	%r13,TF_R13(%rsp)	; \
102 	movq	%r14,TF_R14(%rsp)	; \
103 	movq	%r15,TF_R15(%rsp)	; \
104 	movq	%rbp,TF_RBP(%rsp)	; \
105 	movq	%rbx,TF_RBX(%rsp)	; \
106 	movq	%rax,TF_RAX(%rsp)
107 
108 #define	INTR_RESTORE_GPRS \
109 	movq	TF_RDI(%rsp),%rdi	; \
110 	movq	TF_RSI(%rsp),%rsi	; \
111 	movq	TF_RDX(%rsp),%rdx	; \
112 	movq	TF_RCX(%rsp),%rcx	; \
113 	movq	TF_R8(%rsp),%r8		; \
114 	movq	TF_R9(%rsp),%r9		; \
115 	movq	TF_R10(%rsp),%r10	; \
116 	movq	TF_R11(%rsp),%r11	; \
117 	movq	TF_R12(%rsp),%r12	; \
118 	movq	TF_R13(%rsp),%r13	; \
119 	movq	TF_R14(%rsp),%r14	; \
120 	movq	TF_R15(%rsp),%r15	; \
121 	movq	TF_RBP(%rsp),%rbp	; \
122 	movq	TF_RBX(%rsp),%rbx	; \
123 	movq	TF_RAX(%rsp),%rax
124 
125 #define TEXT_USER_BEGIN	.pushsection	.text.user, "ax"
126 #define TEXT_USER_END	.popsection
127 
128 #ifdef SVS
129 
130 /* XXX: put this somewhere else */
131 #define SVS_UTLS		0xffffc00000000000 /* PMAP_PCPU_BASE */
132 #define UTLS_KPDIRPA		0
133 #define UTLS_SCRATCH		8
134 #define UTLS_RSP0		16
135 
136 #define SVS_ENTER_BYTES	22
137 #define NOSVS_ENTER \
138 	.byte 0xEB, (SVS_ENTER_BYTES-2)	/* jmp */	; \
139 	.fill	(SVS_ENTER_BYTES-2),1,0xCC
140 #define SVS_ENTER \
141 	HOTPATCH(HP_NAME_SVS_ENTER, SVS_ENTER_BYTES)	; \
142 	NOSVS_ENTER
143 
144 #define SVS_LEAVE_BYTES	31
145 #define NOSVS_LEAVE \
146 	.byte 0xEB, (SVS_LEAVE_BYTES-2)	/* jmp */	; \
147 	.fill	(SVS_LEAVE_BYTES-2),1,0xCC
148 #define SVS_LEAVE \
149 	HOTPATCH(HP_NAME_SVS_LEAVE, SVS_LEAVE_BYTES)	; \
150 	NOSVS_LEAVE
151 
152 #define SVS_ENTER_ALT_BYTES	23
153 #define NOSVS_ENTER_ALTSTACK \
154 	.byte 0xEB, (SVS_ENTER_ALT_BYTES-2)	/* jmp */	; \
155 	.fill	(SVS_ENTER_ALT_BYTES-2),1,0xCC
156 #define SVS_ENTER_ALTSTACK \
157 	HOTPATCH(HP_NAME_SVS_ENTER_ALT, SVS_ENTER_ALT_BYTES)	; \
158 	NOSVS_ENTER_ALTSTACK
159 
160 #define SVS_LEAVE_ALT_BYTES	22
161 #define NOSVS_LEAVE_ALTSTACK \
162 	.byte 0xEB, (SVS_LEAVE_ALT_BYTES-2)	/* jmp */	; \
163 	.fill	(SVS_LEAVE_ALT_BYTES-2),1,0xCC
164 #define SVS_LEAVE_ALTSTACK \
165 	HOTPATCH(HP_NAME_SVS_LEAVE_ALT, SVS_LEAVE_ALT_BYTES)	; \
166 	NOSVS_LEAVE_ALTSTACK
167 
168 #else
169 #define SVS_ENTER	/* nothing */
170 #define SVS_LEAVE	/* nothing */
171 #define SVS_ENTER_ALTSTACK	/* nothing */
172 #define SVS_LEAVE_ALTSTACK	/* nothing */
173 #endif
174 
175 #define	INTRENTRY \
176 	subq	$TF_REGSIZE,%rsp	; \
177 	INTR_SAVE_GPRS			; \
178 	cld				; \
179 	SMAP_ENABLE			; \
180 	testb	$SEL_UPL,TF_CS(%rsp)	; \
181 	je	98f			; \
182 	SWAPGS				; \
183 	IBRS_ENTER			; \
184 	SVS_ENTER			; \
185 	movw	%gs,TF_GS(%rsp)		; \
186 	movw	%fs,TF_FS(%rsp)		; \
187 	movw	%es,TF_ES(%rsp)		; \
188 	movw	%ds,TF_DS(%rsp)		; \
189 98:
190 
191 #define INTRFASTEXIT \
192 	jmp	intrfastexit
193 
194 #define INTR_RECURSE_HWFRAME \
195 	movq	%rsp,%r10		; \
196 	movl	%ss,%r11d		; \
197 	pushq	%r11			; \
198 	pushq	%r10			; \
199 	pushfq				; \
200 	pushq	$GSEL(GCODE_SEL,SEL_KPL); \
201 /* XEN: We must fixup CS, as even kernel mode runs at CPL 3 */ \
202  	XEN_ONLY2(andb	$0xfc,(%rsp);)	  \
203 	pushq	%r13			;
204 
205 #define INTR_RECURSE_ENTRY \
206 	subq	$TF_REGSIZE,%rsp	; \
207 	INTR_SAVE_GPRS			; \
208 	cld
209 
210 #define	CHECK_DEFERRED_SWITCH \
211 	cmpl	$0, CPUVAR(WANT_PMAPLOAD)
212 
213 #define CHECK_ASTPENDING(reg)	cmpl	$0, L_MD_ASTPENDING(reg)
214 #define CLEAR_ASTPENDING(reg)	movl	$0, L_MD_ASTPENDING(reg)
215 
216 #endif /* _AMD64_MACHINE_FRAMEASM_H */
217