vm_machdep.c revision 93452
1/*- 2 * Copyright (c) 1982, 1986 The Regents of the University of California. 3 * Copyright (c) 1989, 1990 William Jolitz 4 * Copyright (c) 1994 John Dyson 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department, and William Jolitz. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91 40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ 41 * $FreeBSD: head/sys/powerpc/aim/vm_machdep.c 93452 2002-03-30 20:44:31Z alc $ 42 */ 43/* 44 * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University. 45 * All rights reserved. 46 * 47 * Author: Chris G. Demetriou 48 * 49 * Permission to use, copy, modify and distribute this software and 50 * its documentation is hereby granted, provided that both the copyright 51 * notice and this permission notice appear in all copies of the 52 * software, derivative works or modified versions, and any portions 53 * thereof, and that both notices appear in supporting documentation. 54 * 55 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 56 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 57 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 58 * 59 * Carnegie Mellon requests users of this software to return to 60 * 61 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 62 * School of Computer Science 63 * Carnegie Mellon University 64 * Pittsburgh PA 15213-3890 65 * 66 * any improvements or extensions that they make and grant Carnegie the 67 * rights to redistribute these changes. 68 */ 69 70#include <sys/param.h> 71#include <sys/systm.h> 72#include <sys/proc.h> 73#include <sys/malloc.h> 74#include <sys/bio.h> 75#include <sys/buf.h> 76#include <sys/ktr.h> 77#include <sys/lock.h> 78#include <sys/mutex.h> 79#include <sys/vnode.h> 80#include <sys/vmmeter.h> 81#include <sys/kernel.h> 82#include <sys/sysctl.h> 83#include <sys/unistd.h> 84 85#include <machine/clock.h> 86#include <machine/cpu.h> 87#include <machine/fpu.h> 88#include <machine/md_var.h> 89 90#include <dev/ofw/openfirm.h> 91 92#include <vm/vm.h> 93#include <vm/vm_param.h> 94#include <vm/vm_kern.h> 95#include <vm/vm_page.h> 96#include <vm/vm_map.h> 97#include <vm/vm_extern.h> 98 99#include <sys/user.h> 100 101/* 102 * quick version of vm_fault 103 */ 104int 105vm_fault_quick(v, prot) 106 caddr_t v; 107 int prot; 108{ 109 int r; 110 if (prot & VM_PROT_WRITE) 111 r = subyte(v, fubyte(v)); 112 else 113 r = fubyte(v); 114 return(r); 115} 116 117/* 118 * Finish a fork operation, with process p2 nearly set up. 119 * Copy and update the pcb, set up the stack so that the child 120 * ready to run and return to user mode. 121 */ 122void 123cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags) 124{ 125 struct proc *p1; 126 struct trapframe *tf; 127 struct callframe *cf; 128 struct pcb *pcb; 129 130 KASSERT(td1 == curthread || td1 == &thread0, 131 ("cpu_fork: p1 not curproc and not proc0")); 132 CTR3(KTR_PROC, "cpu_fork: called td1=%08x p2=%08x flags=%x", (u_int)td1, (u_int)p2, flags); 133 134 if ((flags & RFPROC) == 0) 135 return; 136 137 p1 = td1->td_proc; 138 139 pcb = (struct pcb *)((td2->td_kstack + KSTACK_PAGES * PAGE_SIZE - 140 sizeof(struct pcb)) & ~0x2fU); 141 td2->td_pcb = pcb; 142 143 /* Copy the pcb */ 144 bcopy(td1->td_pcb, pcb, sizeof(struct pcb)); 145 146 /* 147 * Create a fresh stack for the new process. 148 * Copy the trap frame for the return to user mode as if from a 149 * syscall. This copies most of the user mode register values. 150 */ 151 tf = (struct trapframe *)pcb - 1; 152 bcopy(td1->td_frame, tf, sizeof(*tf)); 153 154 /* XXX: Set up trap frame? */ 155 156 td2->td_frame = tf; 157 158 cf = (struct callframe *)tf - 1; 159 cf->cf_func = (register_t)fork_return; 160 cf->cf_arg0 = (register_t)td2; 161 cf->cf_arg1 = (register_t)tf; 162 163 pcb->pcb_sp = (register_t)cf; 164 pcb->pcb_lr = (register_t)fork_trampoline; 165 166 /* 167 * Now cpu_switch() can schedule the new process. 168 */ 169} 170 171/* 172 * Intercept the return address from a freshly forked process that has NOT 173 * been scheduled yet. 174 * 175 * This is needed to make kernel threads stay in kernel mode. 176 */ 177void 178cpu_set_fork_handler(td, func, arg) 179 struct thread *td; 180 void (*func)(void *); 181 void *arg; 182{ 183 struct callframe *cf; 184 185 CTR3(KTR_PROC, "cpu_set_fork_handler: called with td=%08x func=%08x arg=%08x", 186 (u_int)td, (u_int)func, (u_int)arg); 187 188 cf = (struct callframe *)td->td_pcb->pcb_sp; 189 190 cf->cf_func = (register_t)func; 191 cf->cf_arg0 = (register_t)arg; 192} 193 194/* 195 * cpu_exit is called as the last action during exit. 196 * We release the address space of the process, block interrupts, 197 * and call switch_exit. switch_exit switches to proc0's PCB and stack, 198 * then jumps into the middle of cpu_switch, as if it were switching 199 * from proc0. 200 */ 201void 202cpu_exit(td) 203 register struct thread *td; 204{ 205} 206 207void 208cpu_wait(td) 209 struct proc *td; 210{ 211} 212 213/* Temporary helper */ 214void 215cpu_throw(void) 216{ 217 218 cpu_switch(); 219 panic("cpu_throw() didn't"); 220} 221 222/* 223 * Dump the machine specific header information at the start of a core dump. 224 */ 225int 226cpu_coredump(td, vp, cred) 227 struct thread *td; 228 struct vnode *vp; 229 struct ucred *cred; 230{ 231 232 return (vn_rdwr(UIO_WRITE, vp, (caddr_t)td->td_proc->p_uarea, 233 ctob(UAREA_PAGES), (off_t)0, UIO_SYSSPACE, IO_UNIT, cred, 234 (int *)NULL, td)); 235} 236 237/* 238 * Map an IO request into kernel virtual address space. 239 * 240 * All requests are (re)mapped into kernel VA space. 241 * Notice that we use b_bufsize for the size of the buffer 242 * to be mapped. b_bcount might be modified by the driver. 243 */ 244void 245vmapbuf(bp) 246 register struct buf *bp; 247{ 248 register caddr_t addr, v, kva; 249 vm_offset_t pa; 250 251 GIANT_REQUIRED; 252 253 if ((bp->b_flags & B_PHYS) == 0) 254 panic("vmapbuf"); 255 256 for (v = bp->b_saveaddr, addr = (caddr_t)trunc_page(bp->b_data); 257 addr < bp->b_data + bp->b_bufsize; 258 addr += PAGE_SIZE, v += PAGE_SIZE) { 259 /* 260 * Do the vm_fault if needed; do the copy-on-write thing 261 * when reading stuff off device into memory. 262 */ 263 vm_fault_quick((addr >= bp->b_data) ? addr : bp->b_data, 264 (bp->b_iocmd == BIO_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 265 pa = trunc_page(pmap_kextract((vm_offset_t) addr)); 266 if (pa == 0) 267 panic("vmapbuf: page not present"); 268 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 269 pmap_kenter((vm_offset_t) v, pa); 270 } 271 272 kva = bp->b_saveaddr; 273 bp->b_saveaddr = bp->b_data; 274 bp->b_data = kva + (((vm_offset_t) bp->b_data) & PAGE_MASK); 275} 276 277/* 278 * Free the io map PTEs associated with this IO operation. 279 * We also invalidate the TLB entries and restore the original b_addr. 280 */ 281void 282vunmapbuf(bp) 283 register struct buf *bp; 284{ 285 register caddr_t addr; 286 vm_offset_t pa; 287 288 GIANT_REQUIRED; 289 290 if ((bp->b_flags & B_PHYS) == 0) 291 panic("vunmapbuf"); 292 293 for (addr = (caddr_t)trunc_page(bp->b_data); 294 addr < bp->b_data + bp->b_bufsize; 295 addr += PAGE_SIZE) { 296 pa = trunc_page(pmap_kextract((vm_offset_t) addr)); 297 pmap_kremove((vm_offset_t) addr); 298 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 299 } 300 301 bp->b_data = bp->b_saveaddr; 302} 303 304/* 305 * Reset back to firmware. 306 */ 307void 308cpu_reset() 309{ 310 OF_exit(); 311} 312 313/* 314 * Software interrupt handler for queued VM system processing. 315 */ 316void 317swi_vm(void *dummy) 318{ 319#if 0 /* XXX: Don't have busdma stuff yet */ 320 if (busdma_swi_pending != 0) 321 busdma_swi(); 322#endif 323} 324 325/* 326 * Tell whether this address is in some physical memory region. 327 * Currently used by the kernel coredump code in order to avoid 328 * dumping the ``ISA memory hole'' which could cause indefinite hangs, 329 * or other unpredictable behaviour. 330 */ 331 332 333int 334is_physical_memory(addr) 335 vm_offset_t addr; 336{ 337 /* 338 * stuff other tests for known memory-mapped devices (PCI?) 339 * here 340 */ 341 342 return 1; 343} 344