xref: /freebsd/sys/amd64/ia32/ia32_reg.c (revision 6cf9a08d2c338e25f0be42326e6880f089156562)
1 /*-
2  * Copyright (c) 2005 Peter Wemm
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_compat.h"
33 
34 #include <sys/param.h>
35 #include <sys/exec.h>
36 #include <sys/fcntl.h>
37 #include <sys/imgact.h>
38 #include <sys/kernel.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/mutex.h>
42 #include <sys/mman.h>
43 #include <sys/namei.h>
44 #include <sys/pioctl.h>
45 #include <sys/proc.h>
46 #include <sys/procfs.h>
47 #include <sys/resourcevar.h>
48 #include <sys/systm.h>
49 #include <sys/signalvar.h>
50 #include <sys/stat.h>
51 #include <sys/sx.h>
52 #include <sys/syscall.h>
53 #include <sys/sysctl.h>
54 #include <sys/sysent.h>
55 #include <sys/vnode.h>
56 
57 #include <vm/vm.h>
58 #include <vm/vm_kern.h>
59 #include <vm/vm_param.h>
60 #include <vm/pmap.h>
61 #include <vm/vm_map.h>
62 #include <vm/vm_object.h>
63 #include <vm/vm_extern.h>
64 
65 #include <compat/freebsd32/freebsd32_util.h>
66 #include <compat/freebsd32/freebsd32_proto.h>
67 #include <machine/fpu.h>
68 #include <compat/ia32/ia32_reg.h>
69 #include <machine/psl.h>
70 #include <machine/segments.h>
71 #include <machine/specialreg.h>
72 #include <machine/frame.h>
73 #include <machine/md_var.h>
74 #include <machine/pcb.h>
75 #include <machine/cpufunc.h>
76 
77 #define	CS_SECURE(cs)		(ISPL(cs) == SEL_UPL)
78 #define	EFL_SECURE(ef, oef)	((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
79 
80 int
81 fill_regs32(struct thread *td, struct reg32 *regs)
82 {
83 	struct pcb *pcb;
84 	struct trapframe *tp;
85 
86 	tp = td->td_frame;
87 	pcb = td->td_pcb;
88 	if (tp->tf_flags & TF_HASSEGS) {
89 		regs->r_gs = tp->tf_gs;
90 		regs->r_fs = tp->tf_fs;
91 		regs->r_es = tp->tf_es;
92 		regs->r_ds = tp->tf_ds;
93 	} else {
94 		regs->r_gs = _ugssel;
95 		regs->r_fs = _ufssel;
96 		regs->r_es = _udatasel;
97 		regs->r_ds = _udatasel;
98 	}
99 	regs->r_edi = tp->tf_rdi;
100 	regs->r_esi = tp->tf_rsi;
101 	regs->r_ebp = tp->tf_rbp;
102 	regs->r_ebx = tp->tf_rbx;
103 	regs->r_edx = tp->tf_rdx;
104 	regs->r_ecx = tp->tf_rcx;
105 	regs->r_eax = tp->tf_rax;
106 	regs->r_eip = tp->tf_rip;
107 	regs->r_cs = tp->tf_cs;
108 	regs->r_eflags = tp->tf_rflags;
109 	regs->r_esp = tp->tf_rsp;
110 	regs->r_ss = tp->tf_ss;
111 	return (0);
112 }
113 
114 int
115 set_regs32(struct thread *td, struct reg32 *regs)
116 {
117 	struct pcb *pcb;
118 	struct trapframe *tp;
119 
120 	tp = td->td_frame;
121 	if (!EFL_SECURE(regs->r_eflags, tp->tf_rflags) || !CS_SECURE(regs->r_cs))
122 		return (EINVAL);
123 	pcb = td->td_pcb;
124 	tp->tf_gs = regs->r_gs;
125 	tp->tf_fs = regs->r_fs;
126 	tp->tf_es = regs->r_es;
127 	tp->tf_ds = regs->r_ds;
128 	td->td_pcb->pcb_full_iret = 1;
129 	tp->tf_flags = TF_HASSEGS;
130 	tp->tf_rdi = regs->r_edi;
131 	tp->tf_rsi = regs->r_esi;
132 	tp->tf_rbp = regs->r_ebp;
133 	tp->tf_rbx = regs->r_ebx;
134 	tp->tf_rdx = regs->r_edx;
135 	tp->tf_rcx = regs->r_ecx;
136 	tp->tf_rax = regs->r_eax;
137 	tp->tf_rip = regs->r_eip;
138 	tp->tf_cs = regs->r_cs;
139 	tp->tf_rflags = regs->r_eflags;
140 	tp->tf_rsp = regs->r_esp;
141 	tp->tf_ss = regs->r_ss;
142 	return (0);
143 }
144 
145 int
146 fill_fpregs32(struct thread *td, struct fpreg32 *regs)
147 {
148 	struct save87 *sv_87 = (struct save87 *)regs;
149 	struct env87 *penv_87 = &sv_87->sv_env;
150 	struct savefpu *sv_fpu = &td->td_pcb->pcb_user_save;
151 	struct envxmm *penv_xmm = &sv_fpu->sv_env;
152 	int i;
153 
154 	bzero(regs, sizeof(*regs));
155 
156 	/* FPU control/status */
157 	penv_87->en_cw = penv_xmm->en_cw;
158 	penv_87->en_sw = penv_xmm->en_sw;
159 	penv_87->en_tw = penv_xmm->en_tw;
160 	/*
161 	 * XXX for en_fip/fcs/foo/fos, check if the fxsave format
162 	 * uses the old-style layout for 32 bit user apps.  If so,
163 	 * read the ip and operand segment registers from there.
164 	 * For now, use the process's %cs/%ds.
165 	 */
166 	penv_87->en_fip = penv_xmm->en_rip;
167 	penv_87->en_fcs = td->td_frame->tf_cs;
168 	penv_87->en_opcode = penv_xmm->en_opcode;
169 	penv_87->en_foo = penv_xmm->en_rdp;
170 	/* Entry into the kernel always sets TF_HASSEGS */
171 	penv_87->en_fos = td->td_frame->tf_ds;
172 
173 	/* FPU registers */
174 	for (i = 0; i < 8; ++i)
175 		sv_87->sv_ac[i] = sv_fpu->sv_fp[i].fp_acc;
176 
177 	return (0);
178 }
179 
180 int
181 set_fpregs32(struct thread *td, struct fpreg32 *regs)
182 {
183 	struct save87 *sv_87 = (struct save87 *)regs;
184 	struct env87 *penv_87 = &sv_87->sv_env;
185 	struct savefpu *sv_fpu = &td->td_pcb->pcb_user_save;
186 	struct envxmm *penv_xmm = &sv_fpu->sv_env;
187 	int i;
188 
189 	/* FPU control/status */
190 	penv_xmm->en_cw = penv_87->en_cw;
191 	penv_xmm->en_sw = penv_87->en_sw;
192 	penv_xmm->en_tw = penv_87->en_tw;
193 	penv_xmm->en_rip = penv_87->en_fip;
194 	/* penv_87->en_fcs and en_fos ignored, see above */
195 	penv_xmm->en_opcode = penv_87->en_opcode;
196 	penv_xmm->en_rdp = penv_87->en_foo;
197 
198 	/* FPU registers */
199 	for (i = 0; i < 8; ++i)
200 		sv_fpu->sv_fp[i].fp_acc = sv_87->sv_ac[i];
201 	for (i = 8; i < 16; ++i)
202 		bzero(&sv_fpu->sv_fp[i].fp_acc, sizeof(sv_fpu->sv_fp[i].fp_acc));
203 
204 	return (0);
205 }
206 
207 int
208 fill_dbregs32(struct thread *td, struct dbreg32 *regs)
209 {
210 	struct dbreg dr;
211 	int err, i;
212 
213 	err = fill_dbregs(td, &dr);
214 	for (i = 0; i < 8; i++)
215 		regs->dr[i] = dr.dr[i];
216 	return (err);
217 }
218 
219 int
220 set_dbregs32(struct thread *td, struct dbreg32 *regs)
221 {
222 	struct dbreg dr;
223 	int i;
224 
225 	for (i = 0; i < 8; i++)
226 		dr.dr[i] = regs->dr[i];
227 	for (i = 8; i < 16; i++)
228 		dr.dr[i] = 0;
229 	return (set_dbregs(td, &dr));
230 }
231