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 * $FreeBSD$ 42 */ 43 44 #include "opt_npx.h" 45 #ifdef PC98 46 #include "opt_pc98.h" 47 #endif 48 #include "opt_reset.h" 49 #include "opt_isa.h" 50 #include "opt_kstack_pages.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/malloc.h> 55 #include <sys/proc.h> 56 #include <sys/bio.h> 57 #include <sys/buf.h> 58 #include <sys/vnode.h> 59 #include <sys/vmmeter.h> 60 #include <sys/kernel.h> 61 #include <sys/ktr.h> 62 #include <sys/mutex.h> 63 #include <sys/smp.h> 64 #include <sys/sysctl.h> 65 #include <sys/unistd.h> 66 67 #include <machine/cpu.h> 68 #include <machine/md_var.h> 69 #include <machine/pcb.h> 70 #include <machine/pcb_ext.h> 71 #include <machine/vm86.h> 72 73 #include <vm/vm.h> 74 #include <vm/vm_param.h> 75 #include <sys/lock.h> 76 #include <vm/vm_kern.h> 77 #include <vm/vm_page.h> 78 #include <vm/vm_map.h> 79 #include <vm/vm_extern.h> 80 81 #include <sys/user.h> 82 83 #ifdef PC98 84 #include <pc98/pc98/pc98.h> 85 #else 86 #include <i386/isa/isa.h> 87 #endif 88 89 static void cpu_reset_real(void); 90 #ifdef SMP 91 static void cpu_reset_proxy(void); 92 static u_int cpu_reset_proxyid; 93 static volatile u_int cpu_reset_proxy_active; 94 #endif 95 extern int _ucodesel, _udatasel; 96 97 /* 98 * quick version of vm_fault 99 */ 100 int 101 vm_fault_quick(v, prot) 102 caddr_t v; 103 int prot; 104 { 105 int r; 106 107 if (prot & VM_PROT_WRITE) 108 r = subyte(v, fubyte(v)); 109 else 110 r = fubyte(v); 111 return(r); 112 } 113 114 /* 115 * Finish a fork operation, with process p2 nearly set up. 116 * Copy and update the pcb, set up the stack so that the child 117 * ready to run and return to user mode. 118 */ 119 void 120 cpu_fork(td1, p2, td2, flags) 121 register struct thread *td1; 122 register struct proc *p2; 123 struct thread *td2; 124 int flags; 125 { 126 register struct proc *p1; 127 struct pcb *pcb2; 128 struct mdproc *mdp2; 129 #ifdef DEV_NPX 130 register_t savecrit; 131 #endif 132 133 p1 = td1->td_proc; 134 if ((flags & RFPROC) == 0) { 135 if ((flags & RFMEM) == 0) { 136 /* unshare user LDT */ 137 struct mdproc *mdp1 = &p1->p_md; 138 struct proc_ldt *pldt = mdp1->md_ldt; 139 if (pldt && pldt->ldt_refcnt > 1) { 140 pldt = user_ldt_alloc(mdp1, pldt->ldt_len); 141 if (pldt == NULL) 142 panic("could not copy LDT"); 143 mdp1->md_ldt = pldt; 144 set_user_ldt(mdp1); 145 user_ldt_free(td1); 146 } 147 } 148 return; 149 } 150 151 /* Ensure that p1's pcb is up to date. */ 152 #ifdef DEV_NPX 153 if (td1 == curthread) 154 td1->td_pcb->pcb_gs = rgs(); 155 savecrit = intr_disable(); 156 if (PCPU_GET(fpcurthread) == td1) 157 npxsave(&td1->td_pcb->pcb_save); 158 intr_restore(savecrit); 159 #endif 160 161 /* Point the pcb to the top of the stack */ 162 pcb2 = (struct pcb *)(td2->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1; 163 td2->td_pcb = pcb2; 164 165 /* Copy p1's pcb */ 166 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 167 168 /* Point mdproc and then copy over td1's contents */ 169 mdp2 = &p2->p_md; 170 bcopy(&p1->p_md, mdp2, sizeof(*mdp2)); 171 172 /* 173 * Create a new fresh stack for the new process. 174 * Copy the trap frame for the return to user mode as if from a 175 * syscall. This copies most of the user mode register values. 176 * The -16 is so we can expand the trapframe if we go to vm86. 177 */ 178 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1; 179 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe)); 180 181 td2->td_frame->tf_eax = 0; /* Child returns zero */ 182 td2->td_frame->tf_eflags &= ~PSL_C; /* success */ 183 td2->td_frame->tf_edx = 1; 184 185 /* 186 * Set registers for trampoline to user mode. Leave space for the 187 * return address on stack. These are the kernel mode register values. 188 */ 189 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir); 190 pcb2->pcb_edi = 0; 191 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */ 192 pcb2->pcb_ebp = 0; 193 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *); 194 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */ 195 pcb2->pcb_eip = (int)fork_trampoline; 196 pcb2->pcb_psl = td2->td_frame->tf_eflags & ~PSL_I; /* ints disabled */ 197 /*- 198 * pcb2->pcb_dr*: cloned above. 199 * pcb2->pcb_savefpu: cloned above. 200 * pcb2->pcb_flags: cloned above. 201 * pcb2->pcb_onfault: cloned above (always NULL here?). 202 * pcb2->pcb_gs: cloned above. 203 * pcb2->pcb_ext: cleared below. 204 */ 205 206 /* 207 * XXX don't copy the i/o pages. this should probably be fixed. 208 */ 209 pcb2->pcb_ext = 0; 210 211 /* Copy the LDT, if necessary. */ 212 mtx_lock_spin(&sched_lock); 213 if (mdp2->md_ldt != 0) { 214 if (flags & RFMEM) { 215 mdp2->md_ldt->ldt_refcnt++; 216 } else { 217 mdp2->md_ldt = user_ldt_alloc(mdp2, 218 mdp2->md_ldt->ldt_len); 219 if (mdp2->md_ldt == NULL) 220 panic("could not copy LDT"); 221 } 222 } 223 mtx_unlock_spin(&sched_lock); 224 225 /* 226 * Now, cpu_switch() can schedule the new process. 227 * pcb_esp is loaded pointing to the cpu_switch() stack frame 228 * containing the return address when exiting cpu_switch. 229 * This will normally be to fork_trampoline(), which will have 230 * %ebx loaded with the new proc's pointer. fork_trampoline() 231 * will set up a stack to call fork_return(p, frame); to complete 232 * the return to user-mode. 233 */ 234 } 235 236 /* 237 * Intercept the return address from a freshly forked process that has NOT 238 * been scheduled yet. 239 * 240 * This is needed to make kernel threads stay in kernel mode. 241 */ 242 void 243 cpu_set_fork_handler(td, func, arg) 244 struct thread *td; 245 void (*func)(void *); 246 void *arg; 247 { 248 /* 249 * Note that the trap frame follows the args, so the function 250 * is really called like this: func(arg, frame); 251 */ 252 td->td_pcb->pcb_esi = (int) func; /* function */ 253 td->td_pcb->pcb_ebx = (int) arg; /* first arg */ 254 } 255 256 void 257 cpu_exit(td) 258 register struct thread *td; 259 { 260 struct pcb *pcb = td->td_pcb; 261 struct mdproc *mdp = &td->td_proc->p_md; 262 #ifdef DEV_NPX 263 npxexit(td); 264 #endif 265 if (pcb->pcb_ext != 0) { 266 /* 267 * XXX do we need to move the TSS off the allocated pages 268 * before freeing them? (not done here) 269 */ 270 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext, 271 ctob(IOPAGES + 1)); 272 pcb->pcb_ext = 0; 273 } 274 if (mdp->md_ldt) 275 user_ldt_free(td); 276 if (pcb->pcb_flags & PCB_DBREGS) { 277 /* 278 * disable all hardware breakpoints 279 */ 280 reset_dbregs(); 281 pcb->pcb_flags &= ~PCB_DBREGS; 282 } 283 } 284 285 void 286 cpu_sched_exit(td) 287 register struct thread *td; 288 { 289 } 290 291 void 292 cpu_wait(p) 293 struct proc *p; 294 { 295 } 296 297 /* 298 * Dump the machine specific header information at the start of a core dump. 299 */ 300 int 301 cpu_coredump(td, vp, cred) 302 struct thread *td; 303 struct vnode *vp; 304 struct ucred *cred; 305 { 306 struct proc *p = td->td_proc; 307 int error; 308 caddr_t tempuser; 309 310 tempuser = malloc(ctob(UAREA_PAGES + KSTACK_PAGES), M_TEMP, M_WAITOK | M_ZERO); 311 if (!tempuser) 312 return EINVAL; 313 314 bcopy(p->p_uarea, tempuser, sizeof(struct user)); 315 #if 0 /* XXXKSE - broken, fixme!!!!! td_frame is in kstack! */ 316 bcopy(td->td_frame, 317 tempuser + ((caddr_t) td->td_frame - (caddr_t) p->p_uarea), 318 sizeof(struct trapframe)); 319 #endif 320 321 error = vn_rdwr(UIO_WRITE, vp, (caddr_t) tempuser, 322 ctob(UAREA_PAGES + KSTACK_PAGES), 323 (off_t)0, UIO_SYSSPACE, IO_UNIT, cred, (int *)NULL, td); 324 325 free(tempuser, M_TEMP); 326 327 return error; 328 } 329 330 /* 331 * Convert kernel VA to physical address 332 */ 333 u_long 334 kvtop(void *addr) 335 { 336 vm_offset_t va; 337 338 va = pmap_kextract((vm_offset_t)addr); 339 if (va == 0) 340 panic("kvtop: zero page frame"); 341 return((int)va); 342 } 343 344 /* 345 * Map an IO request into kernel virtual address space. 346 * 347 * All requests are (re)mapped into kernel VA space. 348 * Notice that we use b_bufsize for the size of the buffer 349 * to be mapped. b_bcount might be modified by the driver. 350 */ 351 void 352 vmapbuf(bp) 353 register struct buf *bp; 354 { 355 register caddr_t addr, kva; 356 vm_offset_t pa; 357 int pidx; 358 struct vm_page *m; 359 360 GIANT_REQUIRED; 361 362 if ((bp->b_flags & B_PHYS) == 0) 363 panic("vmapbuf"); 364 365 for (addr = (caddr_t)trunc_page((vm_offset_t)bp->b_data), pidx = 0; 366 addr < bp->b_data + bp->b_bufsize; 367 addr += PAGE_SIZE, pidx++) { 368 /* 369 * Do the vm_fault if needed; do the copy-on-write thing 370 * when reading stuff off device into memory. 371 */ 372 vm_fault_quick((addr >= bp->b_data) ? addr : bp->b_data, 373 (bp->b_iocmd == BIO_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 374 pa = trunc_page(pmap_kextract((vm_offset_t) addr)); 375 if (pa == 0) 376 panic("vmapbuf: page not present"); 377 m = PHYS_TO_VM_PAGE(pa); 378 vm_page_hold(m); 379 bp->b_pages[pidx] = m; 380 } 381 if (pidx > btoc(MAXPHYS)) 382 panic("vmapbuf: mapped more than MAXPHYS"); 383 pmap_qenter((vm_offset_t)bp->b_saveaddr, bp->b_pages, pidx); 384 385 kva = bp->b_saveaddr; 386 bp->b_npages = pidx; 387 bp->b_saveaddr = bp->b_data; 388 bp->b_data = kva + (((vm_offset_t) bp->b_data) & PAGE_MASK); 389 } 390 391 /* 392 * Free the io map PTEs associated with this IO operation. 393 * We also invalidate the TLB entries and restore the original b_addr. 394 */ 395 void 396 vunmapbuf(bp) 397 register struct buf *bp; 398 { 399 int pidx; 400 int npages; 401 vm_page_t *m; 402 403 GIANT_REQUIRED; 404 405 if ((bp->b_flags & B_PHYS) == 0) 406 panic("vunmapbuf"); 407 408 npages = bp->b_npages; 409 pmap_qremove(trunc_page((vm_offset_t)bp->b_data), 410 npages); 411 m = bp->b_pages; 412 for (pidx = 0; pidx < npages; pidx++) 413 vm_page_unhold(*m++); 414 415 bp->b_data = bp->b_saveaddr; 416 } 417 418 /* 419 * Force reset the processor by invalidating the entire address space! 420 */ 421 422 #ifdef SMP 423 static void 424 cpu_reset_proxy() 425 { 426 427 cpu_reset_proxy_active = 1; 428 while (cpu_reset_proxy_active == 1) 429 ; /* Wait for other cpu to see that we've started */ 430 stop_cpus((1<<cpu_reset_proxyid)); 431 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid); 432 DELAY(1000000); 433 cpu_reset_real(); 434 } 435 #endif 436 437 void 438 cpu_reset() 439 { 440 #ifdef SMP 441 if (smp_active == 0) { 442 cpu_reset_real(); 443 /* NOTREACHED */ 444 } else { 445 446 u_int map; 447 int cnt; 448 printf("cpu_reset called on cpu#%d\n", PCPU_GET(cpuid)); 449 450 map = PCPU_GET(other_cpus) & ~ stopped_cpus; 451 452 if (map != 0) { 453 printf("cpu_reset: Stopping other CPUs\n"); 454 stop_cpus(map); /* Stop all other CPUs */ 455 } 456 457 if (PCPU_GET(cpuid) == 0) { 458 DELAY(1000000); 459 cpu_reset_real(); 460 /* NOTREACHED */ 461 } else { 462 /* We are not BSP (CPU #0) */ 463 464 cpu_reset_proxyid = PCPU_GET(cpuid); 465 cpustop_restartfunc = cpu_reset_proxy; 466 cpu_reset_proxy_active = 0; 467 printf("cpu_reset: Restarting BSP\n"); 468 started_cpus = (1<<0); /* Restart CPU #0 */ 469 470 cnt = 0; 471 while (cpu_reset_proxy_active == 0 && cnt < 10000000) 472 cnt++; /* Wait for BSP to announce restart */ 473 if (cpu_reset_proxy_active == 0) 474 printf("cpu_reset: Failed to restart BSP\n"); 475 enable_intr(); 476 cpu_reset_proxy_active = 2; 477 478 while (1); 479 /* NOTREACHED */ 480 } 481 } 482 #else 483 cpu_reset_real(); 484 #endif 485 } 486 487 static void 488 cpu_reset_real() 489 { 490 491 #ifdef PC98 492 /* 493 * Attempt to do a CPU reset via CPU reset port. 494 */ 495 disable_intr(); 496 if ((inb(0x35) & 0xa0) != 0xa0) { 497 outb(0x37, 0x0f); /* SHUT0 = 0. */ 498 outb(0x37, 0x0b); /* SHUT1 = 0. */ 499 } 500 outb(0xf0, 0x00); /* Reset. */ 501 #else 502 /* 503 * Attempt to do a CPU reset via the keyboard controller, 504 * do not turn of the GateA20, as any machine that fails 505 * to do the reset here would then end up in no man's land. 506 */ 507 508 #if !defined(BROKEN_KEYBOARD_RESET) 509 outb(IO_KBD + 4, 0xFE); 510 DELAY(500000); /* wait 0.5 sec to see if that did it */ 511 printf("Keyboard reset did not work, attempting CPU shutdown\n"); 512 DELAY(1000000); /* wait 1 sec for printf to complete */ 513 #endif 514 #endif /* PC98 */ 515 /* force a shutdown by unmapping entire address space ! */ 516 bzero((caddr_t) PTD, PAGE_SIZE); 517 518 /* "good night, sweet prince .... <THUNK!>" */ 519 invltlb(); 520 /* NOTREACHED */ 521 while(1); 522 } 523 524 /* 525 * Software interrupt handler for queued VM system processing. 526 */ 527 void 528 swi_vm(void *dummy) 529 { 530 if (busdma_swi_pending != 0) 531 busdma_swi(); 532 } 533 534 /* 535 * Tell whether this address is in some physical memory region. 536 * Currently used by the kernel coredump code in order to avoid 537 * dumping the ``ISA memory hole'' which could cause indefinite hangs, 538 * or other unpredictable behaviour. 539 */ 540 541 int 542 is_physical_memory(addr) 543 vm_offset_t addr; 544 { 545 546 #ifdef DEV_ISA 547 /* The ISA ``memory hole''. */ 548 if (addr >= 0xa0000 && addr < 0x100000) 549 return 0; 550 #endif 551 552 /* 553 * stuff other tests for known memory-mapped devices (PCI?) 554 * here 555 */ 556 557 return 1; 558 } 559