1 /*- 2 * SPDX-License-Identifier: BSD-4-Clause 3 * 4 * Copyright (c) 1982, 1986 The Regents of the University of California. 5 * Copyright (c) 1989, 1990 William Jolitz 6 * Copyright (c) 1994 John Dyson 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * the Systems Programming Group of the University of Utah Computer 11 * Science Department, and William Jolitz. 12 * 13 * Redistribution and use in source and binary :forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. All advertising materials mentioning features or use of this software 22 * must display the following acknowledgement: 23 * This product includes software developed by the University of 24 * California, Berkeley and its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/proc.h> 49 #include <sys/socketvar.h> 50 #include <sys/syscall.h> 51 #include <sys/sysctl.h> 52 #include <sys/sysent.h> 53 #include <sys/unistd.h> 54 55 #include <machine/cpu.h> 56 #include <machine/frame.h> 57 #include <machine/pcb.h> 58 #include <machine/sysarch.h> 59 #include <sys/lock.h> 60 #include <sys/mutex.h> 61 62 #include <vm/vm.h> 63 #include <vm/pmap.h> 64 #include <vm/vm_extern.h> 65 #include <vm/vm_kern.h> 66 #include <vm/vm_page.h> 67 #include <vm/vm_map.h> 68 #include <vm/vm_param.h> 69 #include <vm/vm_pageout.h> 70 #include <vm/uma.h> 71 #include <vm/uma_int.h> 72 73 #include <machine/md_var.h> 74 #include <machine/vfp.h> 75 76 /* 77 * struct switchframe and trapframe must both be a multiple of 8 78 * for correct stack alignment. 79 */ 80 _Static_assert((sizeof(struct switchframe) % 8) == 0, "Bad alignment"); 81 _Static_assert((sizeof(struct trapframe) % 8) == 0, "Bad alignment"); 82 83 uint32_t initial_fpscr = VFPSCR_DN | VFPSCR_FZ; 84 85 /* 86 * Finish a fork operation, with process p2 nearly set up. 87 * Copy and update the pcb, set up the stack so that the child 88 * ready to run and return to user mode. 89 */ 90 void 91 cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags) 92 { 93 struct pcb *pcb2; 94 struct trapframe *tf; 95 struct mdproc *mdp2; 96 97 if ((flags & RFPROC) == 0) 98 return; 99 100 /* Point the pcb to the top of the stack */ 101 pcb2 = (struct pcb *) 102 (td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE) - 1; 103 #ifdef VFP 104 /* Store actual state of VFP */ 105 if (curthread == td1) { 106 if ((td1->td_pcb->pcb_fpflags & PCB_FP_STARTED) != 0) 107 vfp_save_state(td1, td1->td_pcb); 108 } 109 #endif 110 td2->td_pcb = pcb2; 111 112 /* Clone td1's pcb */ 113 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 114 115 /* Point to mdproc and then copy over td1's contents */ 116 mdp2 = &p2->p_md; 117 bcopy(&td1->td_proc->p_md, mdp2, sizeof(*mdp2)); 118 119 /* Point the frame to the stack in front of pcb and copy td1's frame */ 120 td2->td_frame = (struct trapframe *)pcb2 - 1; 121 *td2->td_frame = *td1->td_frame; 122 123 /* 124 * Create a new fresh stack for the new process. 125 * Copy the trap frame for the return to user mode as if from a 126 * syscall. This copies most of the user mode register values. 127 */ 128 pmap_set_pcb_pagedir(vmspace_pmap(p2->p_vmspace), pcb2); 129 pcb2->pcb_regs.sf_r4 = (register_t)fork_return; 130 pcb2->pcb_regs.sf_r5 = (register_t)td2; 131 pcb2->pcb_regs.sf_lr = (register_t)fork_trampoline; 132 pcb2->pcb_regs.sf_sp = STACKALIGN(td2->td_frame); 133 pcb2->pcb_regs.sf_tpidrurw = (register_t)get_tls(); 134 135 #ifdef VFP 136 vfp_new_thread(td2, td1, true); 137 #endif 138 139 tf = td2->td_frame; 140 tf->tf_spsr &= ~PSR_C; 141 tf->tf_r0 = 0; 142 tf->tf_r1 = 0; 143 144 /* Setup to release spin count in fork_exit(). */ 145 td2->td_md.md_spinlock_count = 1; 146 td2->td_md.md_saved_cspr = PSR_SVC32_MODE; 147 } 148 149 void 150 cpu_thread_swapin(struct thread *td) 151 { 152 } 153 154 void 155 cpu_thread_swapout(struct thread *td) 156 { 157 } 158 159 void 160 cpu_set_syscall_retval(struct thread *td, int error) 161 { 162 struct trapframe *frame; 163 164 frame = td->td_frame; 165 switch (error) { 166 case 0: 167 frame->tf_r0 = td->td_retval[0]; 168 frame->tf_r1 = td->td_retval[1]; 169 frame->tf_spsr &= ~PSR_C; /* carry bit */ 170 break; 171 case ERESTART: 172 /* 173 * Reconstruct the pc to point at the swi. 174 */ 175 #if __ARM_ARCH >= 7 176 if ((frame->tf_spsr & PSR_T) != 0) 177 frame->tf_pc -= THUMB_INSN_SIZE; 178 else 179 #endif 180 frame->tf_pc -= INSN_SIZE; 181 break; 182 case EJUSTRETURN: 183 /* nothing to do */ 184 break; 185 default: 186 frame->tf_r0 = error; 187 frame->tf_spsr |= PSR_C; /* carry bit */ 188 break; 189 } 190 } 191 192 /* 193 * Initialize machine state, mostly pcb and trap frame for a new 194 * thread, about to return to userspace. Put enough state in the new 195 * thread's PCB to get it to go back to the fork_return(), which 196 * finalizes the thread state and handles peculiarities of the first 197 * return to userspace for the new thread. 198 */ 199 void 200 cpu_copy_thread(struct thread *td, struct thread *td0) 201 { 202 203 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 204 bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb)); 205 206 td->td_pcb->pcb_regs.sf_r4 = (register_t)fork_return; 207 td->td_pcb->pcb_regs.sf_r5 = (register_t)td; 208 td->td_pcb->pcb_regs.sf_lr = (register_t)fork_trampoline; 209 td->td_pcb->pcb_regs.sf_sp = STACKALIGN(td->td_frame); 210 211 td->td_frame->tf_spsr &= ~PSR_C; 212 td->td_frame->tf_r0 = 0; 213 214 #ifdef VFP 215 vfp_new_thread(td, td0, false); 216 #endif 217 218 /* Setup to release spin count in fork_exit(). */ 219 td->td_md.md_spinlock_count = 1; 220 td->td_md.md_saved_cspr = PSR_SVC32_MODE; 221 } 222 223 /* 224 * Set that machine state for performing an upcall that starts 225 * the entry function with the given argument. 226 */ 227 void 228 cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg, 229 stack_t *stack) 230 { 231 struct trapframe *tf = td->td_frame; 232 233 tf->tf_usr_sp = STACKALIGN((int)stack->ss_sp + stack->ss_size); 234 tf->tf_pc = (int)entry; 235 tf->tf_r0 = (int)arg; 236 tf->tf_spsr = PSR_USR32_MODE; 237 if ((register_t)entry & 1) 238 tf->tf_spsr |= PSR_T; 239 } 240 241 int 242 cpu_set_user_tls(struct thread *td, void *tls_base) 243 { 244 245 td->td_pcb->pcb_regs.sf_tpidrurw = (register_t)tls_base; 246 if (td == curthread) 247 set_tls(tls_base); 248 return (0); 249 } 250 251 void 252 cpu_thread_exit(struct thread *td) 253 { 254 } 255 256 void 257 cpu_thread_alloc(struct thread *td) 258 { 259 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages * 260 PAGE_SIZE) - 1; 261 /* 262 * Ensure td_frame is aligned to an 8 byte boundary as it will be 263 * placed into the stack pointer which must be 8 byte aligned in 264 * the ARM EABI. 265 */ 266 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb) - 1; 267 } 268 269 void 270 cpu_thread_free(struct thread *td) 271 { 272 } 273 274 void 275 cpu_thread_clean(struct thread *td) 276 { 277 } 278 279 /* 280 * Intercept the return address from a freshly forked process that has NOT 281 * been scheduled yet. 282 * 283 * This is needed to make kernel threads stay in kernel mode. 284 */ 285 void 286 cpu_fork_kthread_handler(struct thread *td, void (*func)(void *), void *arg) 287 { 288 td->td_pcb->pcb_regs.sf_r4 = (register_t)func; /* function */ 289 td->td_pcb->pcb_regs.sf_r5 = (register_t)arg; /* first arg */ 290 } 291 292 void 293 cpu_exit(struct thread *td) 294 { 295 } 296 297 bool 298 cpu_exec_vmspace_reuse(struct proc *p __unused, vm_map_t map __unused) 299 { 300 301 return (true); 302 } 303 304 int 305 cpu_procctl(struct thread *td __unused, int idtype __unused, id_t id __unused, 306 int com __unused, void *data __unused) 307 { 308 309 return (EINVAL); 310 } 311 312 void 313 cpu_sync_core(void) 314 { 315 } 316