1 /* $NetBSD: netbsd32_machdep.c,v 1.5 2020/11/04 07:09:46 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas of 3am Software Foundry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33
34 __RCSID("$NetBSD: netbsd32_machdep.c,v 1.5 2020/11/04 07:09:46 skrll Exp $");
35
36 #include <sys/param.h>
37 #include <sys/ucontext.h>
38
39 #include <uvm/uvm_extern.h>
40
41 #include <compat/netbsd32/netbsd32.h>
42 #include <compat/netbsd32/netbsd32_syscallargs.h>
43
44 #include <riscv/locore.h>
45
46 char machine_arch32[] = MACHINE_ARCH32;
47 char machine32[] = MACHINE;
48
49 void
netbsd32_setregs(struct lwp * l,struct exec_package * pack,vaddr_t stack)50 netbsd32_setregs(struct lwp *l, struct exec_package *pack, vaddr_t stack)
51 {
52 l->l_proc->p_flag |= PK_32;
53 setregs(l, pack, stack);
54 }
55
56 /*
57 * Start a new LWP
58 */
59 void
startlwp32(void * arg)60 startlwp32(void *arg)
61 {
62 ucontext32_t * const uc = arg;
63 int error __diagused;
64
65 error = cpu_setmcontext32(curlwp, &uc->uc_mcontext, uc->uc_flags);
66 KASSERT(error == 0);
67
68 // Even though this is a ucontext32_t, the space allocated was for a
69 // full ucontext_t
70 kmem_free(uc, sizeof(ucontext_t));
71 userret(curlwp);
72 }
73
74 // We've worked hard to make sure struct reg32 and __gregset32_t are the same.
75 // Ditto for struct fpreg and fregset_t.
76
77 CTASSERT(sizeof(struct reg32) == sizeof(__gregset32_t));
78 CTASSERT(sizeof(struct fpreg) == sizeof(__fregset_t));
79
80 void
cpu_getmcontext32(struct lwp * l,mcontext32_t * mcp,unsigned int * flags)81 cpu_getmcontext32(struct lwp *l, mcontext32_t *mcp, unsigned int *flags)
82 {
83 const struct trapframe * const tf = l->l_md.md_utf;
84
85 /* Save register context. */
86 for (size_t i = _X_RA; i <= _X_GP; i++) {
87 mcp->__gregs[i] = tf->tf_reg[i];
88 }
89 mcp->__gregs[_REG_PC] = tf->tf_pc;
90
91 mcp->__private = (intptr_t)l->l_private;
92
93 *flags |= _UC_CPU | _UC_TLSBASE;
94
95 /* Save floating point register context, if any. */
96 KASSERT(l == curlwp);
97 if (fpu_valid_p(l)) {
98 /*
99 * If this process is the current FP owner, dump its
100 * context to the PCB first.
101 */
102 fpu_save(l);
103
104 struct pcb * const pcb = lwp_getpcb(l);
105 *(struct fpreg *)mcp->__fregs = pcb->pcb_fpregs;
106 *flags |= _UC_FPU;
107 }
108 }
109
110 int
cpu_mcontext32_validate(struct lwp * l,const mcontext32_t * mcp)111 cpu_mcontext32_validate(struct lwp *l, const mcontext32_t *mcp)
112 {
113 /*
114 * Verify that at least the PC and SP are user addresses.
115 */
116 if ((int32_t) mcp->__gregs[_REG_PC] < 0
117 || (int32_t) mcp->__gregs[_REG_SP] < 0
118 || (mcp->__gregs[_REG_PC] & 1))
119 return EINVAL;
120
121 return 0;
122 }
123
124 int
cpu_setmcontext32(struct lwp * l,const mcontext32_t * mcp,unsigned int flags)125 cpu_setmcontext32(struct lwp *l, const mcontext32_t *mcp, unsigned int flags)
126 {
127 struct trapframe * const tf = l->l_md.md_utf;
128 struct proc * const p = l->l_proc;
129 const __greg32_t * const gr = mcp->__gregs;
130 int error;
131
132 /* Restore register context, if any. */
133 if (flags & _UC_CPU) {
134 error = cpu_mcontext32_validate(l, mcp);
135 if (error)
136 return error;
137
138 /* Save register context. */
139 for (size_t i = _X_RA; i <= _X_GP; i++) {
140 tf->tf_reg[i] = (int32_t)gr[i];
141 }
142 tf->tf_pc = (int32_t) gr[_REG_PC];
143 }
144
145 /* Restore the private thread context */
146 if (flags & _UC_TLSBASE) {
147 lwp_setprivate(l, (void *)(intptr_t)(int32_t)mcp->__private);
148 }
149
150 /* Restore floating point register context, if any. */
151 if (flags & _UC_FPU) {
152 KASSERT(l == curlwp);
153 /* Tell PCU we are replacing the FPU contents. */
154 fpu_replace(l);
155
156 /*
157 * The PCB FP regs struct includes the FP CSR, so use the
158 * proper size of fpreg when copying.
159 */
160 struct pcb * const pcb = lwp_getpcb(l);
161 pcb->pcb_fpregs = *(const struct fpreg *)mcp->__fregs;
162 }
163
164 mutex_enter(p->p_lock);
165 if (flags & _UC_SETSTACK)
166 l->l_sigstk.ss_flags |= SS_ONSTACK;
167 if (flags & _UC_CLRSTACK)
168 l->l_sigstk.ss_flags &= ~SS_ONSTACK;
169 mutex_exit(p->p_lock);
170
171 return (0);
172 }
173
174 int
netbsd32_sysarch(struct lwp * l,const struct netbsd32_sysarch_args * uap,register_t * retval)175 netbsd32_sysarch(struct lwp *l, const struct netbsd32_sysarch_args *uap,
176 register_t *retval)
177 {
178 return ENOSYS;
179 }
180
181 vaddr_t
netbsd32_vm_default_addr(struct proc * p,vaddr_t base,vsize_t size,int topdown)182 netbsd32_vm_default_addr(struct proc *p, vaddr_t base, vsize_t size,
183 int topdown)
184 {
185 if (topdown)
186 return VM_DEFAULT_ADDRESS32_TOPDOWN(base, size);
187 else
188 return VM_DEFAULT_ADDRESS32_BOTTOMUP(base, size);
189 }
190