xref: /freebsd/sys/arm/arm/sys_machdep.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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 #include "opt_capsicum.h"
36 #include "opt_ktrace.h"
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/capsicum.h>
41 #include <sys/ktrace.h>
42 #include <sys/proc.h>
43 #include <sys/sysproto.h>
44 #include <sys/syscall.h>
45 #include <sys/sysent.h>
46 #include <vm/vm.h>
47 #include <vm/vm_extern.h>
48 
49 #include <machine/cpu.h>
50 #include <machine/sysarch.h>
51 #include <machine/machdep.h>
52 #include <machine/vmparam.h>
53 
54 #ifndef _SYS_SYSPROTO_H_
55 struct sysarch_args {
56 	int op;
57 	char *parms;
58 };
59 #endif
60 
61 /* Prototypes */
62 static int arm32_sync_icache (struct thread *, void *);
63 static int arm32_drain_writebuf(struct thread *, void *);
64 
65 static int
66 sync_icache(uintptr_t addr, size_t len)
67 {
68 	size_t size;
69 	vm_offset_t rv;
70 
71 	 /* Align starting address to cacheline size */
72 	len += addr & cpuinfo.dcache_line_mask;
73 	addr &= ~cpuinfo.dcache_line_mask;
74 
75 	/* Break whole range to pages. */
76 	do {
77 		size = PAGE_SIZE - (addr & PAGE_MASK);
78 		size = min(size, len);
79 		rv = dcache_wb_pou_checked(addr, size);
80 		if (rv == 1) /* see dcache_wb_pou_checked() */
81 			rv = icache_inv_pou_checked(addr, size);
82 		if (rv != 1) {
83 			if (!useracc((void *)addr, size, VM_PROT_READ)) {
84 				/* Invalid access */
85 				return (rv);
86 			}
87 			/* Valid but unmapped page - skip it. */
88 		}
89 		len -= size;
90 		addr += size;
91 	} while (len > 0);
92 
93 	/* Invalidate branch predictor buffer. */
94 	bpb_inv_all();
95 	return (1);
96 }
97 
98 static int
99 arm32_sync_icache(struct thread *td, void *args)
100 {
101 	struct arm_sync_icache_args ua;
102 	int error;
103 	ksiginfo_t ksi;
104 	vm_offset_t rv;
105 
106 	if ((error = copyin(args, &ua, sizeof(ua))) != 0)
107 		return (error);
108 
109 	if  (ua.len == 0) {
110 		td->td_retval[0] = 0;
111 		return (0);
112 	}
113 
114 	/*
115 	 * Validate arguments. Address and length are unsigned,
116 	 * so we can use wrapped overflow check.
117 	 */
118 	if (((ua.addr + ua.len) < ua.addr) ||
119 	    ((ua.addr + ua.len) > VM_MAXUSER_ADDRESS)) {
120 		ksiginfo_init_trap(&ksi);
121 		ksi.ksi_signo = SIGSEGV;
122 		ksi.ksi_code = SEGV_ACCERR;
123 		ksi.ksi_addr = (void *)max(ua.addr, VM_MAXUSER_ADDRESS);
124 		trapsignal(td, &ksi);
125 		return (EINVAL);
126 	}
127 
128 	rv = sync_icache(ua.addr, ua.len);
129 	if (rv != 1) {
130 		ksiginfo_init_trap(&ksi);
131 		ksi.ksi_signo = SIGSEGV;
132 		ksi.ksi_code = SEGV_MAPERR;
133 		ksi.ksi_addr = (void *)rv;
134 		trapsignal(td, &ksi);
135 		return (EINVAL);
136 	}
137 
138 	td->td_retval[0] = 0;
139 	return (0);
140 }
141 
142 static int
143 arm32_drain_writebuf(struct thread *td, void *args)
144 {
145 	/* No args. */
146 
147 	dsb();
148 	cpu_l2cache_drain_writebuf();
149 	td->td_retval[0] = 0;
150 	return (0);
151 }
152 
153 static int
154 arm32_set_tp(struct thread *td, void *args)
155 {
156 
157 	set_tls(args);
158 	return (0);
159 }
160 
161 static int
162 arm32_get_tp(struct thread *td, void *args)
163 {
164 
165 	td->td_retval[0] = (register_t)get_tls();
166 	return (0);
167 }
168 
169 int
170 sysarch(struct thread *td, struct sysarch_args *uap)
171 {
172 	int error;
173 
174 #ifdef CAPABILITY_MODE
175 	/*
176 	 * When adding new operations, add a new case statement here to
177 	 * explicitly indicate whether or not the operation is safe to
178 	 * perform in capability mode.
179 	 */
180 	if (IN_CAPABILITY_MODE(td)) {
181 		switch (uap->op) {
182 		case ARM_SYNC_ICACHE:
183 		case ARM_DRAIN_WRITEBUF:
184 		case ARM_SET_TP:
185 		case ARM_GET_TP:
186 		case ARM_GET_VFPSTATE:
187 			break;
188 
189 		default:
190 #ifdef KTRACE
191 			if (KTRPOINT(td, KTR_CAPFAIL))
192 				ktrcapfail(CAPFAIL_SYSCALL, NULL, NULL);
193 #endif
194 			return (ECAPMODE);
195 		}
196 	}
197 #endif
198 
199 	switch (uap->op) {
200 	case ARM_SYNC_ICACHE:
201 		error = arm32_sync_icache(td, uap->parms);
202 		break;
203 	case ARM_DRAIN_WRITEBUF:
204 		error = arm32_drain_writebuf(td, uap->parms);
205 		break;
206 	case ARM_SET_TP:
207 		error = arm32_set_tp(td, uap->parms);
208 		break;
209 	case ARM_GET_TP:
210 		error = arm32_get_tp(td, uap->parms);
211 		break;
212 	case ARM_GET_VFPSTATE:
213 		error = arm_get_vfpstate(td, uap->parms);
214 		break;
215 	default:
216 		error = EINVAL;
217 		break;
218 	}
219 	return (error);
220 }
221