1 /* $NetBSD: netbsd32_machdep.c,v 1.7 2026/10/20 06:40:44 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 1.7 2026/10/20 06:40:44 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/frame.h> 45 #include <riscv/locore.h> 46 #include <riscv/userret.h> 47 48 char machine_arch32[] = MACHINE_ARCH32; 49 char machine32[] = MACHINE; 50 51 void 52 netbsd32_setregs(struct lwp *l, struct exec_package *pack, vaddr_t stack) 53 { 54 l->l_proc->p_flag |= PK_32; 55 setregs(l, pack, stack); 56 } 57 58 /* 59 * Start a new LWP 60 */ 61 void 62 startlwp32(void *arg) 63 { 64 ucontext32_t * const uc = arg; 65 int error __diagused; 66 67 error = cpu_setmcontext32(curlwp, &uc->uc_mcontext, uc->uc_flags); 68 KASSERT(error == 0); 69 70 // Even though this is a ucontext32_t, the space allocated was for a 71 // full ucontext_t 72 kmem_free(uc, sizeof(ucontext_t)); 73 userret(curlwp); 74 } 75 76 // We've worked hard to make sure struct reg32 and __gregset32_t are the same. 77 // Ditto for struct fpreg and fregset_t. 78 79 CTASSERT(sizeof(struct reg32) == sizeof(__gregset32_t)); 80 CTASSERT(sizeof(struct fpreg) == sizeof(__fregset_t)); 81 82 void 83 cpu_getmcontext32(struct lwp *l, mcontext32_t *mcp, unsigned int *flags) 84 { 85 const struct trapframe * const tf = l->l_md.md_utf; 86 87 /* Save register context. */ 88 for (size_t i = _X_RA; i <= _X_T6; i++) { 89 mcp->__gregs[i] = tf->tf_reg[i]; 90 } 91 mcp->__gregs[_REG_PC] = tf->tf_pc; 92 93 mcp->__gregs[_REG_TP] = (uint32_t)(uintptr_t)l->l_private; 94 95 *flags |= _UC_CPU | _UC_TLSBASE; 96 97 /* Save floating point register context, if any. */ 98 KASSERT(l == curlwp); 99 if (fpu_valid_p(l)) { 100 /* 101 * If this process is the current FP owner, dump its 102 * context to the PCB first. 103 */ 104 fpu_save(l); 105 106 struct pcb * const pcb = lwp_getpcb(l); 107 *(struct fpreg *)mcp->__fregs = pcb->pcb_fpregs; 108 *flags |= _UC_FPU; 109 } 110 } 111 112 int 113 cpu_mcontext32_validate(struct lwp *l, const mcontext32_t *mcp) 114 { 115 /* 116 * Verify that at least the PC and SP are user addresses. 117 */ 118 if ((int32_t) mcp->__gregs[_REG_PC] < 0 119 || (int32_t) mcp->__gregs[_REG_SP] < 0 120 || (mcp->__gregs[_REG_PC] & 1)) 121 return EINVAL; 122 123 return 0; 124 } 125 126 int 127 cpu_setmcontext32(struct lwp *l, const mcontext32_t *mcp, unsigned int flags) 128 { 129 struct trapframe * const tf = l->l_md.md_utf; 130 struct proc * const p = l->l_proc; 131 const __greg32_t * const gr = mcp->__gregs; 132 int error; 133 134 /* Restore register context, if any. */ 135 if (flags & _UC_CPU) { 136 error = cpu_mcontext32_validate(l, mcp); 137 if (error) 138 return error; 139 140 /* Save register context. */ 141 for (size_t i = _X_RA; i <= _X_T6; i++) { 142 tf->tf_reg[i] = (int32_t)gr[i]; 143 } 144 tf->tf_pc = (int32_t) gr[_REG_PC]; 145 } 146 147 /* Restore the private thread context */ 148 if (flags & _UC_TLSBASE) { 149 lwp_setprivate(l, 150 (void *)(uintptr_t)(uint32_t)mcp->__gregs[_REG_TP]); 151 } 152 153 /* Restore floating point register context, if any. */ 154 if (flags & _UC_FPU) { 155 KASSERT(l == curlwp); 156 /* Tell PCU we are replacing the FPU contents. */ 157 fpu_replace(l); 158 159 /* 160 * The PCB FP regs struct includes the FP CSR, so use the 161 * proper size of fpreg when copying. 162 */ 163 struct pcb * const pcb = lwp_getpcb(l); 164 pcb->pcb_fpregs = *(const struct fpreg *)mcp->__fregs; 165 } 166 167 mutex_enter(p->p_lock); 168 if (flags & _UC_SETSTACK) 169 l->l_sigstk.ss_flags |= SS_ONSTACK; 170 if (flags & _UC_CLRSTACK) 171 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 172 mutex_exit(p->p_lock); 173 174 return (0); 175 } 176 177 int 178 netbsd32_sysarch(struct lwp *l, const struct netbsd32_sysarch_args *uap, 179 register_t *retval) 180 { 181 return ENOSYS; 182 } 183 184 vaddr_t 185 netbsd32_vm_default_addr(struct proc *p, vaddr_t base, vsize_t size, 186 int topdown) 187 { 188 if (topdown) 189 return VM_DEFAULT_ADDRESS32_TOPDOWN(base, size); 190 else 191 return VM_DEFAULT_ADDRESS32_BOTTOMUP(base, size); 192 } 193 194 void 195 netbsd32_machdep_md_init(void) 196 { 197 198 /* nothing to do */ 199 } 200 201 void 202 netbsd32_machdep_md_fini(void) 203 { 204 205 /* nothing to do */ 206 } 207
Indexes created Sun Oct 25 00:26:45 UTC 2026