xref: /freebsd/sys/arm/arm/sys_machdep.c (revision 4e8d558c)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990 The Regents of the University of California.
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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	from: @(#)sys_machdep.c	5.5 (Berkeley) 1/19/91
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_capsicum.h"
38 #include "opt_ktrace.h"
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/capsicum.h>
43 #include <sys/ktrace.h>
44 #include <sys/proc.h>
45 #include <sys/sysproto.h>
46 #include <sys/syscall.h>
47 #include <sys/sysent.h>
48 #include <vm/vm.h>
49 #include <vm/vm_extern.h>
50 
51 #include <machine/cpu.h>
52 #include <machine/sysarch.h>
53 #include <machine/machdep.h>
54 #include <machine/vmparam.h>
55 
56 #ifndef _SYS_SYSPROTO_H_
57 struct sysarch_args {
58 	int op;
59 	char *parms;
60 };
61 #endif
62 
63 /* Prototypes */
64 static int arm32_sync_icache (struct thread *, void *);
65 static int arm32_drain_writebuf(struct thread *, void *);
66 
67 static int
68 sync_icache(uintptr_t addr, size_t len)
69 {
70 	size_t size;
71 	vm_offset_t rv;
72 
73 	 /* Align starting address to cacheline size */
74 	len += addr & cpuinfo.dcache_line_mask;
75 	addr &= ~cpuinfo.dcache_line_mask;
76 
77 	/* Break whole range to pages. */
78 	do {
79 		size = PAGE_SIZE - (addr & PAGE_MASK);
80 		size = min(size, len);
81 		rv = dcache_wb_pou_checked(addr, size);
82 		if (rv == 1) /* see dcache_wb_pou_checked() */
83 			rv = icache_inv_pou_checked(addr, size);
84 		if (rv != 1) {
85 			if (!useracc((void *)addr, size, VM_PROT_READ)) {
86 				/* Invalid access */
87 				return (rv);
88 			}
89 			/* Valid but unmapped page - skip it. */
90 		}
91 		len -= size;
92 		addr += size;
93 	} while (len > 0);
94 
95 	/* Invalidate branch predictor buffer. */
96 	bpb_inv_all();
97 	return (1);
98 }
99 
100 static int
101 arm32_sync_icache(struct thread *td, void *args)
102 {
103 	struct arm_sync_icache_args ua;
104 	int error;
105 	ksiginfo_t ksi;
106 	vm_offset_t rv;
107 
108 	if ((error = copyin(args, &ua, sizeof(ua))) != 0)
109 		return (error);
110 
111 	if  (ua.len == 0) {
112 		td->td_retval[0] = 0;
113 		return (0);
114 	}
115 
116 	/*
117 	 * Validate arguments. Address and length are unsigned,
118 	 * so we can use wrapped overflow check.
119 	 */
120 	if (((ua.addr + ua.len) < ua.addr) ||
121 	    ((ua.addr + ua.len) > VM_MAXUSER_ADDRESS)) {
122 		ksiginfo_init_trap(&ksi);
123 		ksi.ksi_signo = SIGSEGV;
124 		ksi.ksi_code = SEGV_ACCERR;
125 		ksi.ksi_addr = (void *)max(ua.addr, VM_MAXUSER_ADDRESS);
126 		trapsignal(td, &ksi);
127 		return (EINVAL);
128 	}
129 
130 	rv = sync_icache(ua.addr, ua.len);
131 	if (rv != 1) {
132 		ksiginfo_init_trap(&ksi);
133 		ksi.ksi_signo = SIGSEGV;
134 		ksi.ksi_code = SEGV_MAPERR;
135 		ksi.ksi_addr = (void *)rv;
136 		trapsignal(td, &ksi);
137 		return (EINVAL);
138 	}
139 
140 	td->td_retval[0] = 0;
141 	return (0);
142 }
143 
144 static int
145 arm32_drain_writebuf(struct thread *td, void *args)
146 {
147 	/* No args. */
148 
149 	dsb();
150 	cpu_l2cache_drain_writebuf();
151 	td->td_retval[0] = 0;
152 	return (0);
153 }
154 
155 static int
156 arm32_set_tp(struct thread *td, void *args)
157 {
158 
159 	set_tls(args);
160 	return (0);
161 }
162 
163 static int
164 arm32_get_tp(struct thread *td, void *args)
165 {
166 
167 	td->td_retval[0] = (register_t)get_tls();
168 	return (0);
169 }
170 
171 int
172 sysarch(struct thread *td, struct sysarch_args *uap)
173 {
174 	int error;
175 
176 #ifdef CAPABILITY_MODE
177 	/*
178 	 * When adding new operations, add a new case statement here to
179 	 * explicitly indicate whether or not the operation is safe to
180 	 * perform in capability mode.
181 	 */
182 	if (IN_CAPABILITY_MODE(td)) {
183 		switch (uap->op) {
184 		case ARM_SYNC_ICACHE:
185 		case ARM_DRAIN_WRITEBUF:
186 		case ARM_SET_TP:
187 		case ARM_GET_TP:
188 		case ARM_GET_VFPSTATE:
189 			break;
190 
191 		default:
192 #ifdef KTRACE
193 			if (KTRPOINT(td, KTR_CAPFAIL))
194 				ktrcapfail(CAPFAIL_SYSCALL, NULL, NULL);
195 #endif
196 			return (ECAPMODE);
197 		}
198 	}
199 #endif
200 
201 	switch (uap->op) {
202 	case ARM_SYNC_ICACHE:
203 		error = arm32_sync_icache(td, uap->parms);
204 		break;
205 	case ARM_DRAIN_WRITEBUF:
206 		error = arm32_drain_writebuf(td, uap->parms);
207 		break;
208 	case ARM_SET_TP:
209 		error = arm32_set_tp(td, uap->parms);
210 		break;
211 	case ARM_GET_TP:
212 		error = arm32_get_tp(td, uap->parms);
213 		break;
214 	case ARM_GET_VFPSTATE:
215 		error = arm_get_vfpstate(td, uap->parms);
216 		break;
217 	default:
218 		error = EINVAL;
219 		break;
220 	}
221 	return (error);
222 }
223