vm_machdep.c revision 103407
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/amd64/amd64/vm_machdep.c 103407 2002-09-16 19:25:08Z mini $ 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/kse.h> 57#include <sys/bio.h> 58#include <sys/buf.h> 59#include <sys/vnode.h> 60#include <sys/vmmeter.h> 61#include <sys/kernel.h> 62#include <sys/ktr.h> 63#include <sys/mutex.h> 64#include <sys/smp.h> 65#include <sys/sysctl.h> 66#include <sys/unistd.h> 67 68#include <machine/cpu.h> 69#include <machine/md_var.h> 70#include <machine/pcb.h> 71#include <machine/pcb_ext.h> 72#include <machine/vm86.h> 73 74#include <vm/vm.h> 75#include <vm/vm_param.h> 76#include <sys/lock.h> 77#include <vm/vm_kern.h> 78#include <vm/vm_page.h> 79#include <vm/vm_map.h> 80#include <vm/vm_extern.h> 81 82#include <sys/user.h> 83 84#ifdef PC98 85#include <pc98/pc98/pc98.h> 86#else 87#include <i386/isa/isa.h> 88#endif 89 90static void cpu_reset_real(void); 91#ifdef SMP 92static void cpu_reset_proxy(void); 93static u_int cpu_reset_proxyid; 94static volatile u_int cpu_reset_proxy_active; 95#endif 96extern int _ucodesel, _udatasel; 97 98/* 99 * quick version of vm_fault 100 */ 101int 102vm_fault_quick(v, prot) 103 caddr_t v; 104 int prot; 105{ 106 int r; 107 108 if (prot & VM_PROT_WRITE) 109 r = subyte(v, fubyte(v)); 110 else 111 r = fubyte(v); 112 return(r); 113} 114 115/* 116 * Finish a fork operation, with process p2 nearly set up. 117 * Copy and update the pcb, set up the stack so that the child 118 * ready to run and return to user mode. 119 */ 120void 121cpu_fork(td1, p2, td2, flags) 122 register struct thread *td1; 123 register struct proc *p2; 124 struct thread *td2; 125 int flags; 126{ 127 register struct proc *p1; 128 struct pcb *pcb2; 129 struct mdproc *mdp2; 130#ifdef DEV_NPX 131 register_t savecrit; 132#endif 133 134 p1 = td1->td_proc; 135 if ((flags & RFPROC) == 0) { 136 if ((flags & RFMEM) == 0) { 137 /* unshare user LDT */ 138 struct mdproc *mdp1 = &p1->p_md; 139 struct proc_ldt *pldt = mdp1->md_ldt; 140 if (pldt && pldt->ldt_refcnt > 1) { 141 pldt = user_ldt_alloc(mdp1, pldt->ldt_len); 142 if (pldt == NULL) 143 panic("could not copy LDT"); 144 mdp1->md_ldt = pldt; 145 set_user_ldt(mdp1); 146 user_ldt_free(td1); 147 } 148 } 149 return; 150 } 151 152 /* Ensure that p1's pcb is up to date. */ 153#ifdef DEV_NPX 154 if (td1 == curthread) 155 td1->td_pcb->pcb_gs = rgs(); 156 savecrit = intr_disable(); 157 if (PCPU_GET(fpcurthread) == td1) 158 npxsave(&td1->td_pcb->pcb_save); 159 intr_restore(savecrit); 160#endif 161 162 /* Point the pcb to the top of the stack */ 163 pcb2 = (struct pcb *)(td2->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1; 164 td2->td_pcb = pcb2; 165 166 /* Copy p1's pcb */ 167 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 168 169 /* Point mdproc and then copy over td1's contents */ 170 mdp2 = &p2->p_md; 171 bcopy(&p1->p_md, mdp2, sizeof(*mdp2)); 172 173 /* 174 * Create a new fresh stack for the new process. 175 * Copy the trap frame for the return to user mode as if from a 176 * syscall. This copies most of the user mode register values. 177 * The -16 is so we can expand the trapframe if we go to vm86. 178 */ 179 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1; 180 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe)); 181 182 td2->td_frame->tf_eax = 0; /* Child returns zero */ 183 td2->td_frame->tf_eflags &= ~PSL_C; /* success */ 184 td2->td_frame->tf_edx = 1; 185 186 /* 187 * Set registers for trampoline to user mode. Leave space for the 188 * return address on stack. These are the kernel mode register values. 189 */ 190 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir); 191 pcb2->pcb_edi = 0; 192 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */ 193 pcb2->pcb_ebp = 0; 194 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *); 195 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */ 196 pcb2->pcb_eip = (int)fork_trampoline; 197 pcb2->pcb_psl = td2->td_frame->tf_eflags & ~PSL_I; /* ints disabled */ 198 /*- 199 * pcb2->pcb_dr*: cloned above. 200 * pcb2->pcb_savefpu: cloned above. 201 * pcb2->pcb_flags: cloned above. 202 * pcb2->pcb_onfault: cloned above (always NULL here?). 203 * pcb2->pcb_gs: cloned above. 204 * pcb2->pcb_ext: cleared below. 205 */ 206 207 /* 208 * XXX don't copy the i/o pages. this should probably be fixed. 209 */ 210 pcb2->pcb_ext = 0; 211 212 /* Copy the LDT, if necessary. */ 213 mtx_lock_spin(&sched_lock); 214 if (mdp2->md_ldt != 0) { 215 if (flags & RFMEM) { 216 mdp2->md_ldt->ldt_refcnt++; 217 } else { 218 mdp2->md_ldt = user_ldt_alloc(mdp2, 219 mdp2->md_ldt->ldt_len); 220 if (mdp2->md_ldt == NULL) 221 panic("could not copy LDT"); 222 } 223 } 224 mtx_unlock_spin(&sched_lock); 225 226 /* 227 * Now, cpu_switch() can schedule the new process. 228 * pcb_esp is loaded pointing to the cpu_switch() stack frame 229 * containing the return address when exiting cpu_switch. 230 * This will normally be to fork_trampoline(), which will have 231 * %ebx loaded with the new proc's pointer. fork_trampoline() 232 * will set up a stack to call fork_return(p, frame); to complete 233 * the return to user-mode. 234 */ 235} 236 237/* 238 * Intercept the return address from a freshly forked process that has NOT 239 * been scheduled yet. 240 * 241 * This is needed to make kernel threads stay in kernel mode. 242 */ 243void 244cpu_set_fork_handler(td, func, arg) 245 struct thread *td; 246 void (*func)(void *); 247 void *arg; 248{ 249 /* 250 * Note that the trap frame follows the args, so the function 251 * is really called like this: func(arg, frame); 252 */ 253 td->td_pcb->pcb_esi = (int) func; /* function */ 254 td->td_pcb->pcb_ebx = (int) arg; /* first arg */ 255} 256 257void 258cpu_exit(struct thread *td) 259{ 260 struct mdproc *mdp; 261 262 mdp = &td->td_proc->p_md; 263 if (mdp->md_ldt) 264 user_ldt_free(td); 265 reset_dbregs(); 266} 267 268void 269cpu_thread_exit(struct thread *td) 270{ 271 struct pcb *pcb = td->td_pcb; 272#ifdef DEV_NPX 273 npxexit(td); 274#endif 275 if (pcb->pcb_ext != 0) { 276 /* XXXKSE XXXSMP not SMP SAFE.. what locks do we have? */ 277 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */ 278 /* 279 * XXX do we need to move the TSS off the allocated pages 280 * before freeing them? (not done here) 281 */ 282 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext, 283 ctob(IOPAGES + 1)); 284 pcb->pcb_ext = 0; 285 } 286 if (pcb->pcb_flags & PCB_DBREGS) { 287 /* 288 * disable all hardware breakpoints 289 */ 290 reset_dbregs(); 291 pcb->pcb_flags &= ~PCB_DBREGS; 292 } 293} 294 295void 296cpu_sched_exit(td) 297 register struct thread *td; 298{ 299} 300 301void 302cpu_thread_setup(struct thread *td) 303{ 304 305 td->td_pcb = 306 (struct pcb *)(td->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1; 307 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1; 308} 309 310/* 311 * Initialize machine state (pcb and trap frame) for a new thread about to 312 * upcall. 313 */ 314void 315cpu_set_upcall(struct thread *td, void *pcb) 316{ 317 struct pcb *pcb2; 318 319 td->td_flags |= TDF_UPCALLING; 320 321 /* Point the pcb to the top of the stack. */ 322 pcb2 = td->td_pcb; 323 324 /* 325 * Copy the upcall pcb. This loads kernel regs. 326 * Those not loaded individually below get their default 327 * values here. 328 * 329 * XXXKSE It might be a good idea to simply skip this as 330 * the values of the other registers may be unimportant. 331 * This would remove any requirement for knowing the KSE 332 * at this time (see the matching comment below for 333 * more analysis) (need a good safe default). 334 */ 335 bcopy(pcb, pcb2, sizeof(*pcb2)); 336 337 /* 338 * Create a new fresh stack for the new thread. 339 * The -16 is so we can expand the trapframe if we go to vm86. 340 * Don't forget to set this stack value into whatever supplies 341 * the address for the fault handlers. 342 * The contexts are filled in at the time we actually DO the 343 * upcall as only then do we know which KSE we got. 344 */ 345 td->td_frame = (struct trapframe *)((caddr_t)pcb2 - 16) - 1; 346 347 /* 348 * Set registers for trampoline to user mode. Leave space for the 349 * return address on stack. These are the kernel mode register values. 350 */ 351 pcb2->pcb_cr3 = vtophys(vmspace_pmap(td->td_proc->p_vmspace)->pm_pdir); 352 pcb2->pcb_edi = 0; 353 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */ 354 pcb2->pcb_ebp = 0; 355 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */ 356 pcb2->pcb_ebx = (int)td; /* trampoline arg */ 357 pcb2->pcb_eip = (int)fork_trampoline; 358 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */ 359 /* 360 * If we didn't copy the pcb, we'd need to do the following registers: 361 * pcb2->pcb_dr*: cloned above. 362 * pcb2->pcb_savefpu: cloned above. 363 * pcb2->pcb_flags: cloned above. 364 * pcb2->pcb_onfault: cloned above (always NULL here?). 365 * pcb2->pcb_gs: cloned above. XXXKSE ??? 366 * pcb2->pcb_ext: cleared below. 367 */ 368 pcb2->pcb_ext = NULL; 369} 370 371/* 372 * Set the machine state for performing an upcall that had to 373 * wait until we selected a KSE to perform the upcall on. 374 */ 375void 376cpu_set_upcall_kse(struct thread *td, struct kse *ke) 377{ 378 379 /* 380 * Set the trap frame to point at the beginning of the uts 381 * function. 382 */ 383 td->td_frame->tf_esp = 384 (int)ke->ke_stack.ss_sp + ke->ke_stack.ss_size - 16; 385 td->td_frame->tf_eip = (int)ke->ke_upcall; 386 387 /* 388 * Pass the address of the mailbox for this kse to the uts 389 * function as a parameter on the stack. 390 */ 391 suword((void *)(td->td_frame->tf_esp + sizeof(void *)), 392 (int)ke->ke_mailbox); 393} 394 395void 396cpu_wait(p) 397 struct proc *p; 398{ 399} 400 401/* 402 * Convert kernel VA to physical address 403 */ 404u_long 405kvtop(void *addr) 406{ 407 vm_offset_t va; 408 409 va = pmap_kextract((vm_offset_t)addr); 410 if (va == 0) 411 panic("kvtop: zero page frame"); 412 return((int)va); 413} 414 415/* 416 * Map an IO request into kernel virtual address space. 417 * 418 * All requests are (re)mapped into kernel VA space. 419 * Notice that we use b_bufsize for the size of the buffer 420 * to be mapped. b_bcount might be modified by the driver. 421 */ 422void 423vmapbuf(bp) 424 register struct buf *bp; 425{ 426 register caddr_t addr, kva; 427 vm_offset_t pa; 428 int pidx; 429 struct vm_page *m; 430 431 GIANT_REQUIRED; 432 433 if ((bp->b_flags & B_PHYS) == 0) 434 panic("vmapbuf"); 435 436 for (addr = (caddr_t)trunc_page((vm_offset_t)bp->b_data), pidx = 0; 437 addr < bp->b_data + bp->b_bufsize; 438 addr += PAGE_SIZE, pidx++) { 439 /* 440 * Do the vm_fault if needed; do the copy-on-write thing 441 * when reading stuff off device into memory. 442 */ 443 vm_fault_quick((addr >= bp->b_data) ? addr : bp->b_data, 444 (bp->b_iocmd == BIO_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 445 pa = trunc_page(pmap_kextract((vm_offset_t) addr)); 446 if (pa == 0) 447 panic("vmapbuf: page not present"); 448 m = PHYS_TO_VM_PAGE(pa); 449 vm_page_hold(m); 450 bp->b_pages[pidx] = m; 451 } 452 if (pidx > btoc(MAXPHYS)) 453 panic("vmapbuf: mapped more than MAXPHYS"); 454 pmap_qenter((vm_offset_t)bp->b_saveaddr, bp->b_pages, pidx); 455 456 kva = bp->b_saveaddr; 457 bp->b_npages = pidx; 458 bp->b_saveaddr = bp->b_data; 459 bp->b_data = kva + (((vm_offset_t) bp->b_data) & PAGE_MASK); 460} 461 462/* 463 * Free the io map PTEs associated with this IO operation. 464 * We also invalidate the TLB entries and restore the original b_addr. 465 */ 466void 467vunmapbuf(bp) 468 register struct buf *bp; 469{ 470 int pidx; 471 int npages; 472 vm_page_t *m; 473 474 GIANT_REQUIRED; 475 476 if ((bp->b_flags & B_PHYS) == 0) 477 panic("vunmapbuf"); 478 479 npages = bp->b_npages; 480 pmap_qremove(trunc_page((vm_offset_t)bp->b_data), 481 npages); 482 m = bp->b_pages; 483 for (pidx = 0; pidx < npages; pidx++) 484 vm_page_unhold(*m++); 485 486 bp->b_data = bp->b_saveaddr; 487} 488 489/* 490 * Force reset the processor by invalidating the entire address space! 491 */ 492 493#ifdef SMP 494static void 495cpu_reset_proxy() 496{ 497 498 cpu_reset_proxy_active = 1; 499 while (cpu_reset_proxy_active == 1) 500 ; /* Wait for other cpu to see that we've started */ 501 stop_cpus((1<<cpu_reset_proxyid)); 502 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid); 503 DELAY(1000000); 504 cpu_reset_real(); 505} 506#endif 507 508void 509cpu_reset() 510{ 511#ifdef SMP 512 if (smp_active == 0) { 513 cpu_reset_real(); 514 /* NOTREACHED */ 515 } else { 516 517 u_int map; 518 int cnt; 519 printf("cpu_reset called on cpu#%d\n", PCPU_GET(cpuid)); 520 521 map = PCPU_GET(other_cpus) & ~ stopped_cpus; 522 523 if (map != 0) { 524 printf("cpu_reset: Stopping other CPUs\n"); 525 stop_cpus(map); /* Stop all other CPUs */ 526 } 527 528 if (PCPU_GET(cpuid) == 0) { 529 DELAY(1000000); 530 cpu_reset_real(); 531 /* NOTREACHED */ 532 } else { 533 /* We are not BSP (CPU #0) */ 534 535 cpu_reset_proxyid = PCPU_GET(cpuid); 536 cpustop_restartfunc = cpu_reset_proxy; 537 cpu_reset_proxy_active = 0; 538 printf("cpu_reset: Restarting BSP\n"); 539 started_cpus = (1<<0); /* Restart CPU #0 */ 540 541 cnt = 0; 542 while (cpu_reset_proxy_active == 0 && cnt < 10000000) 543 cnt++; /* Wait for BSP to announce restart */ 544 if (cpu_reset_proxy_active == 0) 545 printf("cpu_reset: Failed to restart BSP\n"); 546 enable_intr(); 547 cpu_reset_proxy_active = 2; 548 549 while (1); 550 /* NOTREACHED */ 551 } 552 } 553#else 554 cpu_reset_real(); 555#endif 556} 557 558static void 559cpu_reset_real() 560{ 561 562#ifdef PC98 563 /* 564 * Attempt to do a CPU reset via CPU reset port. 565 */ 566 disable_intr(); 567 if ((inb(0x35) & 0xa0) != 0xa0) { 568 outb(0x37, 0x0f); /* SHUT0 = 0. */ 569 outb(0x37, 0x0b); /* SHUT1 = 0. */ 570 } 571 outb(0xf0, 0x00); /* Reset. */ 572#else 573 /* 574 * Attempt to do a CPU reset via the keyboard controller, 575 * do not turn of the GateA20, as any machine that fails 576 * to do the reset here would then end up in no man's land. 577 */ 578 579#if !defined(BROKEN_KEYBOARD_RESET) 580 outb(IO_KBD + 4, 0xFE); 581 DELAY(500000); /* wait 0.5 sec to see if that did it */ 582 printf("Keyboard reset did not work, attempting CPU shutdown\n"); 583 DELAY(1000000); /* wait 1 sec for printf to complete */ 584#endif 585#endif /* PC98 */ 586 /* force a shutdown by unmapping entire address space ! */ 587 bzero((caddr_t) PTD, PAGE_SIZE); 588 589 /* "good night, sweet prince .... <THUNK!>" */ 590 invltlb(); 591 /* NOTREACHED */ 592 while(1); 593} 594 595/* 596 * Software interrupt handler for queued VM system processing. 597 */ 598void 599swi_vm(void *dummy) 600{ 601 if (busdma_swi_pending != 0) 602 busdma_swi(); 603} 604 605/* 606 * Tell whether this address is in some physical memory region. 607 * Currently used by the kernel coredump code in order to avoid 608 * dumping the ``ISA memory hole'' which could cause indefinite hangs, 609 * or other unpredictable behaviour. 610 */ 611 612int 613is_physical_memory(addr) 614 vm_offset_t addr; 615{ 616 617#ifdef DEV_ISA 618 /* The ISA ``memory hole''. */ 619 if (addr >= 0xa0000 && addr < 0x100000) 620 return 0; 621#endif 622 623 /* 624 * stuff other tests for known memory-mapped devices (PCI?) 625 * here 626 */ 627 628 return 1; 629} 630