1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright 2019 Joyent, Inc.
24 */
25
26 /*
27 * This is an assembly file that gets #include-ed into the brand-specific
28 * assembly files (e.g. sn1_brand_asm.s) for Solaris-derived brands.
29 * We can't make these into functions since in the trap context there's
30 * no easy place to save the extra parameters that would be required, so
31 * each brand module needs its own copy of this code. We #include this and
32 * use brand-specific #defines to replace the XXX_brand_... definitions.
33 */
34
35 #ifdef lint
36
37 #include <sys/systm.h>
38
39 #else /* !lint */
40
41 #include <sys/asm_linkage.h>
42 #include <sys/privregs.h>
43 #include <sys/segments.h>
44 #include "assym.h"
45 #include "brand_asm.h"
46
47 #endif /* !lint */
48
49 #ifdef lint
50
51 void
52 XXX_brand_sysenter_callback(void)
53 {
54 }
55
56 void
57 XXX_brand_syscall_callback(void)
58 {
59 }
60
61 #if defined(__amd64)
62 void
63 XXX_brand_syscall32_callback(void)
64 {
65 }
66 #endif /* amd64 */
67
68 void
69 XXX_brand_int91_callback(void)
70 {
71 }
72
73 #else /* !lint */
74
75 #ifdef _ASM /* The remainder of this file is only for assembly files */
76
77 #if defined(__amd64)
78
79 /*
80 * syscall handler for 32-bit user processes:
81 * See "64-BIT INTERPOSITION STACK" in brand_asm.h.
82 * To 'return' to our user-space handler, we just need to place its address
83 * into %rcx. The original return address is passed back in SYSCALL_REG.
84 */
85 ENTRY(XXX_brand_syscall32_callback)
86 CALLBACK_PROLOGUE(XXX_emulation_table, SPD_HANDLER, SYSCALL_REG,
87 SCR_REG, SCR_REGB);
88 CALC_TABLE_ADDR(SCR_REG, SPD_HANDLER);
89 mov %rcx, SYSCALL_REG; /* save orig return addr in syscall_reg */
90 mov SCR_REG, %rcx; /* place new return addr in %rcx */
91 mov %gs:CPU_RTMP_R15, SCR_REG; /* restore scratch register */
92 call *x86_md_clear /* Flush micro-arch state */
93 mov V_SSP(SP_REG), SP_REG /* restore user stack pointer */
94 jmp nopop_sys_syscall32_swapgs_sysretl
95 9:
96 retq
97 SET_SIZE(XXX_brand_syscall32_callback)
98
99 /*
100 * syscall handler for 64-bit user processes:
101 * See "64-BIT INTERPOSITION STACK" in brand_asm.h.
102 * To 'return' to our user-space handler, we just need to place its address
103 * into %rcx. The original return address is passed back in SYSCALL_REG.
104 */
105 ENTRY(XXX_brand_syscall_callback)
106 CALLBACK_PROLOGUE(XXX_emulation_table, SPD_HANDLER, SYSCALL_REG,
107 SCR_REG, SCR_REGB);
108 CALC_TABLE_ADDR(SCR_REG, SPD_HANDLER);
109 mov %rcx, SYSCALL_REG; /* save orig return addr in syscall_reg */
110 mov SCR_REG, %rcx; /* place new return addr in %rcx */
111 mov %gs:CPU_RTMP_R15, SCR_REG; /* restore scratch register */
112 call *x86_md_clear /* Flush micro-arch state */
113 mov V_SSP(SP_REG), SP_REG /* restore user stack pointer */
114 jmp nopop_sys_syscall_swapgs_sysretq
115 9:
116 retq
117 SET_SIZE(XXX_brand_syscall_callback)
118
119 /*
120 * See "64-BIT INTERPOSITION STACK" in brand_asm.h.
121 * To 'return' to our user-space handler, we just need to place its address
122 * into %rdx. The original return address is passed back in SYSCALL_REG.
123 */
124 ENTRY(XXX_brand_sysenter_callback)
125 CALLBACK_PROLOGUE(XXX_emulation_table, SPD_HANDLER, SYSCALL_REG,
126 SCR_REG, SCR_REGB);
127 CALC_TABLE_ADDR(SCR_REG, SPD_HANDLER);
128 mov %rdx, SYSCALL_REG; /* save orig return addr in syscall_reg */
129 mov SCR_REG, %rdx; /* place new return addr in %rdx */
130 mov %gs:CPU_RTMP_R15, SCR_REG; /* restore scratch register */
131 mov V_SSP(SP_REG), SP_REG /* restore user stack pointer */
132 jmp sys_sysenter_swapgs_sysexit
133 9:
134 ret
135 SET_SIZE(XXX_brand_sysenter_callback)
136
137 /*
138 * To 'return' to our user-space handler we need to update the user's %eip
139 * pointer in the saved interrupt state on the stack. The interrupt state was
140 * pushed onto our stack automatically when the interrupt occured; see the
141 * comments above. The original return address is passed back in SYSCALL_REG.
142 * See "64-BIT INTERPOSITION STACK" and "64-BIT INT STACK" in brand_asm.h.
143 */
144 ENTRY(XXX_brand_int91_callback)
145 CALLBACK_PROLOGUE(XXX_emulation_table, SPD_HANDLER, SYSCALL_REG,
146 SCR_REG, SCR_REGB);
147 CALC_TABLE_ADDR(SCR_REG, SPD_HANDLER); /* new ret addr is in scratch */
148 mov SCR_REG, SYSCALL_REG; /* place new ret addr in syscallreg */
149 mov %gs:CPU_RTMP_R15, SCR_REG; /* restore scratch register */
150 mov V_SSP(SP_REG), SP_REG; /* restore intr stack pointer */
151 /*CSTYLED*/
152 xchg (SP_REG), SYSCALL_REG /* swap new and orig. return addrs */
153 jmp sys_sysint_swapgs_iret
154 9:
155 retq
156 SET_SIZE(XXX_brand_int91_callback)
157
158 #else /* !__amd64 */
159
160 /*
161 * To 'return' to our user-space handler, we need to replace the iret target
162 * address. The original return address is passed back in %eax.
163 * See "32-BIT INTERPOSITION STACK" and "32-BIT INT STACK" in brand_asm.h.
164 */
165 ENTRY(XXX_brand_syscall_callback)
166 CALLBACK_PROLOGUE(XXX_emulation_table, SPD_HANDLER, SYSCALL_REG,
167 SCR_REG, SCR_REGB);
168 CALC_TABLE_ADDR(SCR_REG, SPD_HANDLER); /* new ret addr is in scratch */
169 mov SCR_REG, SYSCALL_REG; /* place new ret addr in syscallreg */
170 GET_V(SP_REG, 0, V_U_EBX, SCR_REG); /* restore scratch register */
171 add $V_END, SP_REG; /* restore intr stack pointer */
172 /*CSTYLED*/
173 xchg (SP_REG), SYSCALL_REG /* swap new and orig. return addrs */
174 jmp nopop_sys_rtt_syscall
175 9:
176 ret
177 SET_SIZE(XXX_brand_syscall_callback)
178
179 /*
180 * To 'return' to our user-space handler, we just need to place its address
181 * into %edx. The original return address is passed back in SYSCALL_REG.
182 * See "32-BIT INTERPOSITION STACK" in brand_asm.h.
183 */
184 ENTRY(XXX_brand_sysenter_callback)
185 CALLBACK_PROLOGUE(XXX_emulation_table, SPD_HANDLER, SYSCALL_REG,
186 SCR_REG, SCR_REGB);
187 mov %edx, SCR_REG; /* save orig return addr in scr reg */
188 CALC_TABLE_ADDR(%edx, SPD_HANDLER); /* new return addr is in %edx */
189 mov SCR_REG, SYSCALL_REG; /* save orig return addr in %eax */
190 GET_V(SP_REG, 0, V_U_EBX, SCR_REG) /* restore scratch register */
191 sysexit
192 9:
193 ret
194 SET_SIZE(XXX_brand_sysenter_callback)
195
196 #endif /* !__amd64 */
197 #endif /* _ASM */
198 #endif /* !lint */