1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2005 Peter Wemm
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/param.h>
30#include <sys/elf.h>
31#include <sys/exec.h>
32#include <sys/fcntl.h>
33#include <sys/imgact.h>
34#include <sys/kernel.h>
35#include <sys/lock.h>
36#include <sys/malloc.h>
37#include <sys/mutex.h>
38#include <sys/mman.h>
39#include <sys/namei.h>
40#include <sys/proc.h>
41#include <sys/procfs.h>
42#include <sys/reg.h>
43#include <sys/resourcevar.h>
44#include <sys/systm.h>
45#include <sys/signalvar.h>
46#include <sys/stat.h>
47#include <sys/sx.h>
48#include <sys/syscall.h>
49#include <sys/sysctl.h>
50#include <sys/sysent.h>
51#include <sys/vnode.h>
52
53#include <vm/vm.h>
54#include <vm/vm_kern.h>
55#include <vm/vm_param.h>
56#include <vm/pmap.h>
57#include <vm/vm_map.h>
58#include <vm/vm_object.h>
59#include <vm/vm_extern.h>
60
61#include <compat/freebsd32/freebsd32_util.h>
62#include <compat/freebsd32/freebsd32_proto.h>
63#include <machine/fpu.h>
64#include <machine/psl.h>
65#include <machine/segments.h>
66#include <machine/specialreg.h>
67#include <machine/frame.h>
68#include <machine/md_var.h>
69#include <machine/pcb.h>
70#include <machine/cpufunc.h>
71
72int
73fill_regs32(struct thread *td, struct reg32 *regs)
74{
75	struct trapframe *tp;
76
77	tp = td->td_frame;
78	if (tp->tf_flags & TF_HASSEGS) {
79		regs->r_gs = tp->tf_gs;
80		regs->r_fs = tp->tf_fs;
81		regs->r_es = tp->tf_es;
82		regs->r_ds = tp->tf_ds;
83	} else {
84		regs->r_gs = _ugssel;
85		regs->r_fs = _ufssel;
86		regs->r_es = _udatasel;
87		regs->r_ds = _udatasel;
88	}
89	regs->r_edi = tp->tf_rdi;
90	regs->r_esi = tp->tf_rsi;
91	regs->r_ebp = tp->tf_rbp;
92	regs->r_ebx = tp->tf_rbx;
93	regs->r_edx = tp->tf_rdx;
94	regs->r_ecx = tp->tf_rcx;
95	regs->r_eax = tp->tf_rax;
96	regs->r_eip = tp->tf_rip;
97	regs->r_cs = tp->tf_cs;
98	regs->r_eflags = tp->tf_rflags;
99	regs->r_esp = tp->tf_rsp;
100	regs->r_ss = tp->tf_ss;
101	regs->r_err = 0;
102	regs->r_trapno = 0;
103	return (0);
104}
105
106int
107set_regs32(struct thread *td, struct reg32 *regs)
108{
109	struct trapframe *tp;
110
111	tp = td->td_frame;
112	if (!EFL_SECURE(regs->r_eflags, tp->tf_rflags) || !CS_SECURE(regs->r_cs))
113		return (EINVAL);
114	tp->tf_gs = regs->r_gs;
115	tp->tf_fs = regs->r_fs;
116	tp->tf_es = regs->r_es;
117	tp->tf_ds = regs->r_ds;
118	set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
119	tp->tf_flags = TF_HASSEGS;
120	tp->tf_rdi = regs->r_edi;
121	tp->tf_rsi = regs->r_esi;
122	tp->tf_rbp = regs->r_ebp;
123	tp->tf_rbx = regs->r_ebx;
124	tp->tf_rdx = regs->r_edx;
125	tp->tf_rcx = regs->r_ecx;
126	tp->tf_rax = regs->r_eax;
127	tp->tf_rip = regs->r_eip;
128	tp->tf_cs = regs->r_cs;
129	tp->tf_rflags = regs->r_eflags;
130	tp->tf_rsp = regs->r_esp;
131	tp->tf_ss = regs->r_ss;
132	return (0);
133}
134
135int
136fill_fpregs32(struct thread *td, struct fpreg32 *regs)
137{
138	struct savefpu *sv_fpu;
139	struct save87 *sv_87;
140	struct env87 *penv_87;
141	struct envxmm *penv_xmm;
142	struct fpacc87 *fx_reg;
143	int i, st;
144	uint64_t mantissa;
145	uint16_t tw, exp;
146	uint8_t ab_tw;
147
148	bzero(regs, sizeof(*regs));
149	sv_87 = (struct save87 *)regs;
150	penv_87 = &sv_87->sv_env;
151	fpugetregs(td);
152	sv_fpu = get_pcb_user_save_td(td);
153	penv_xmm = &sv_fpu->sv_env;
154
155	/* FPU control/status */
156	penv_87->en_cw = penv_xmm->en_cw;
157	penv_87->en_sw = penv_xmm->en_sw;
158
159	/*
160	 * XXX for en_fip/fcs/foo/fos, check if the fxsave format
161	 * uses the old-style layout for 32 bit user apps.  If so,
162	 * read the ip and operand segment registers from there.
163	 * For now, use the process's %cs/%ds.
164	 */
165	penv_87->en_fip = penv_xmm->en_rip;
166	penv_87->en_fcs = td->td_frame->tf_cs;
167	penv_87->en_opcode = penv_xmm->en_opcode;
168	penv_87->en_foo = penv_xmm->en_rdp;
169	/* Entry into the kernel always sets TF_HASSEGS */
170	penv_87->en_fos = td->td_frame->tf_ds;
171
172	/*
173	 * FPU registers and tags.
174	 * For ST(i), i = fpu_reg - top; we start with fpu_reg=7.
175	 */
176	st = 7 - ((penv_xmm->en_sw >> 11) & 7);
177	ab_tw = penv_xmm->en_tw;
178	tw = 0;
179	for (i = 0x80; i != 0; i >>= 1) {
180		sv_87->sv_ac[st] = sv_fpu->sv_fp[st].fp_acc;
181		tw <<= 2;
182		if ((ab_tw & i) != 0) {
183			/* Non-empty - we need to check ST(i) */
184			fx_reg = &sv_fpu->sv_fp[st].fp_acc;
185			/* The first 64 bits contain the mantissa. */
186			mantissa = *((uint64_t *)fx_reg->fp_bytes);
187			/*
188			 * The final 16 bits contain the sign bit and the exponent.
189			 * Mask the sign bit since it is of no consequence to these
190			 * tests.
191			 */
192			exp = *((uint16_t *)&fx_reg->fp_bytes[8]) & 0x7fff;
193			if (exp == 0) {
194				if (mantissa == 0)
195					tw |= 1; /* Zero */
196				else
197					tw |= 2; /* Denormal */
198			} else if (exp == 0x7fff)
199				tw |= 2; /* Infinity or NaN */
200		} else
201			tw |= 3; /* Empty */
202		st = (st - 1) & 7;
203	}
204	penv_87->en_tw = tw;
205
206	return (0);
207}
208
209int
210set_fpregs32(struct thread *td, struct fpreg32 *regs)
211{
212	struct save87 *sv_87 = (struct save87 *)regs;
213	struct env87 *penv_87 = &sv_87->sv_env;
214	struct savefpu *sv_fpu = get_pcb_user_save_td(td);
215	struct envxmm *penv_xmm = &sv_fpu->sv_env;
216	int i;
217
218	/* FPU control/status */
219	penv_xmm->en_cw = penv_87->en_cw;
220	penv_xmm->en_sw = penv_87->en_sw;
221	penv_xmm->en_rip = penv_87->en_fip;
222	/* penv_87->en_fcs and en_fos ignored, see above */
223	penv_xmm->en_opcode = penv_87->en_opcode;
224	penv_xmm->en_rdp = penv_87->en_foo;
225
226	/* FPU registers and tags */
227	penv_xmm->en_tw = 0;
228	for (i = 0; i < 8; ++i) {
229		sv_fpu->sv_fp[i].fp_acc = sv_87->sv_ac[i];
230		if ((penv_87->en_tw & (3 << i * 2)) != (3 << i * 2))
231			penv_xmm->en_tw |= 1 << i;
232	}
233
234	for (i = 8; i < 16; ++i)
235		bzero(&sv_fpu->sv_fp[i].fp_acc, sizeof(sv_fpu->sv_fp[i].fp_acc));
236	fpuuserinited(td);
237
238	return (0);
239}
240
241int
242fill_dbregs32(struct thread *td, struct dbreg32 *regs)
243{
244	struct dbreg dr;
245	int err, i;
246
247	err = fill_dbregs(td, &dr);
248	for (i = 0; i < 8; i++)
249		regs->dr[i] = dr.dr[i];
250	return (err);
251}
252
253int
254set_dbregs32(struct thread *td, struct dbreg32 *regs)
255{
256	struct dbreg dr;
257	int i;
258
259	for (i = 0; i < 8; i++)
260		dr.dr[i] = regs->dr[i];
261	for (i = 8; i < 16; i++)
262		dr.dr[i] = 0;
263	return (set_dbregs(td, &dr));
264}
265
266static bool
267get_i386_segbases(struct regset *rs, struct thread *td, void *buf,
268    size_t *sizep)
269{
270	struct segbasereg32 *reg;
271	struct pcb *pcb;
272
273	if (buf != NULL) {
274		KASSERT(*sizep == sizeof(*reg), ("%s: invalid size", __func__));
275		reg = buf;
276
277		pcb = td->td_pcb;
278		if (td == curthread)
279			update_pcb_bases(pcb);
280		reg->r_fsbase = pcb->pcb_fsbase;
281		reg->r_gsbase = pcb->pcb_gsbase;
282	}
283	*sizep = sizeof(*reg);
284	return (true);
285}
286
287static bool
288set_i386_segbases(struct regset *rs, struct thread *td, void *buf,
289    size_t size)
290{
291	struct segbasereg32 *reg;
292	struct pcb *pcb;
293
294	KASSERT(size == sizeof(*reg), ("%s: invalid size", __func__));
295	reg = buf;
296
297	pcb = td->td_pcb;
298	set_pcb_flags(pcb, PCB_FULL_IRET);
299	pcb->pcb_fsbase = reg->r_fsbase;
300	td->td_frame->tf_fs = _ufssel;
301	pcb->pcb_gsbase = reg->r_gsbase;
302	td->td_frame->tf_gs = _ugssel;
303
304	return (true);
305}
306
307static struct regset regset_i386_segbases = {
308	.note = NT_X86_SEGBASES,
309	.size = sizeof(struct segbasereg),
310	.get = get_i386_segbases,
311	.set = set_i386_segbases,
312};
313ELF32_REGSET(regset_i386_segbases);
314