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 */ 42 43 #include <sys/cdefs.h> 44 __FBSDID("$FreeBSD$"); 45 46 #include "opt_isa.h" 47 #include "opt_npx.h" 48 #include "opt_reset.h" 49 #include "opt_cpu.h" 50 #include "opt_xbox.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/bio.h> 55 #include <sys/buf.h> 56 #include <sys/kernel.h> 57 #include <sys/ktr.h> 58 #include <sys/lock.h> 59 #include <sys/malloc.h> 60 #include <sys/mbuf.h> 61 #include <sys/mutex.h> 62 #include <sys/pioctl.h> 63 #include <sys/proc.h> 64 #include <sys/sysent.h> 65 #include <sys/sf_buf.h> 66 #include <sys/smp.h> 67 #include <sys/sched.h> 68 #include <sys/sysctl.h> 69 #include <sys/unistd.h> 70 #include <sys/vnode.h> 71 #include <sys/vmmeter.h> 72 73 #include <machine/cpu.h> 74 #include <machine/cputypes.h> 75 #include <machine/md_var.h> 76 #include <machine/pcb.h> 77 #include <machine/pcb_ext.h> 78 #include <machine/smp.h> 79 #include <machine/vm86.h> 80 81 #ifdef CPU_ELAN 82 #include <machine/elan_mmcr.h> 83 #endif 84 85 #include <vm/vm.h> 86 #include <vm/vm_extern.h> 87 #include <vm/vm_kern.h> 88 #include <vm/vm_page.h> 89 #include <vm/vm_map.h> 90 #include <vm/vm_param.h> 91 92 #ifdef XEN 93 #include <xen/hypervisor.h> 94 #endif 95 #ifdef PC98 96 #include <pc98/cbus/cbus.h> 97 #else 98 #include <x86/isa/isa.h> 99 #endif 100 101 #ifdef XBOX 102 #include <machine/xbox.h> 103 #endif 104 105 #ifndef NSFBUFS 106 #define NSFBUFS (512 + maxusers * 16) 107 #endif 108 109 static void cpu_reset_real(void); 110 #ifdef SMP 111 static void cpu_reset_proxy(void); 112 static u_int cpu_reset_proxyid; 113 static volatile u_int cpu_reset_proxy_active; 114 #endif 115 static void sf_buf_init(void *arg); 116 SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL); 117 118 LIST_HEAD(sf_head, sf_buf); 119 120 /* 121 * A hash table of active sendfile(2) buffers 122 */ 123 static struct sf_head *sf_buf_active; 124 static u_long sf_buf_hashmask; 125 126 #define SF_BUF_HASH(m) (((m) - vm_page_array) & sf_buf_hashmask) 127 128 static TAILQ_HEAD(, sf_buf) sf_buf_freelist; 129 static u_int sf_buf_alloc_want; 130 131 /* 132 * A lock used to synchronize access to the hash table and free list 133 */ 134 static struct mtx sf_buf_lock; 135 136 extern int _ucodesel, _udatasel; 137 138 /* 139 * Finish a fork operation, with process p2 nearly set up. 140 * Copy and update the pcb, set up the stack so that the child 141 * ready to run and return to user mode. 142 */ 143 void 144 cpu_fork(td1, p2, td2, flags) 145 register struct thread *td1; 146 register struct proc *p2; 147 struct thread *td2; 148 int flags; 149 { 150 register struct proc *p1; 151 struct pcb *pcb2; 152 struct mdproc *mdp2; 153 154 p1 = td1->td_proc; 155 if ((flags & RFPROC) == 0) { 156 if ((flags & RFMEM) == 0) { 157 /* unshare user LDT */ 158 struct mdproc *mdp1 = &p1->p_md; 159 struct proc_ldt *pldt, *pldt1; 160 161 mtx_lock_spin(&dt_lock); 162 if ((pldt1 = mdp1->md_ldt) != NULL && 163 pldt1->ldt_refcnt > 1) { 164 pldt = user_ldt_alloc(mdp1, pldt1->ldt_len); 165 if (pldt == NULL) 166 panic("could not copy LDT"); 167 mdp1->md_ldt = pldt; 168 set_user_ldt(mdp1); 169 user_ldt_deref(pldt1); 170 } else 171 mtx_unlock_spin(&dt_lock); 172 } 173 return; 174 } 175 176 /* Ensure that td1's pcb is up to date. */ 177 if (td1 == curthread) 178 td1->td_pcb->pcb_gs = rgs(); 179 #ifdef DEV_NPX 180 critical_enter(); 181 if (PCPU_GET(fpcurthread) == td1) 182 npxsave(td1->td_pcb->pcb_save); 183 critical_exit(); 184 #endif 185 186 /* Point the pcb to the top of the stack */ 187 pcb2 = (struct pcb *)(td2->td_kstack + 188 td2->td_kstack_pages * PAGE_SIZE) - 1; 189 td2->td_pcb = pcb2; 190 191 /* Copy td1's pcb */ 192 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 193 194 /* Properly initialize pcb_save */ 195 pcb2->pcb_save = &pcb2->pcb_user_save; 196 197 /* Point mdproc and then copy over td1's contents */ 198 mdp2 = &p2->p_md; 199 bcopy(&p1->p_md, mdp2, sizeof(*mdp2)); 200 201 /* 202 * Create a new fresh stack for the new process. 203 * Copy the trap frame for the return to user mode as if from a 204 * syscall. This copies most of the user mode register values. 205 * The -16 is so we can expand the trapframe if we go to vm86. 206 */ 207 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1; 208 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe)); 209 210 td2->td_frame->tf_eax = 0; /* Child returns zero */ 211 td2->td_frame->tf_eflags &= ~PSL_C; /* success */ 212 td2->td_frame->tf_edx = 1; 213 214 /* 215 * If the parent process has the trap bit set (i.e. a debugger had 216 * single stepped the process to the system call), we need to clear 217 * the trap flag from the new frame unless the debugger had set PF_FORK 218 * on the parent. Otherwise, the child will receive a (likely 219 * unexpected) SIGTRAP when it executes the first instruction after 220 * returning to userland. 221 */ 222 if ((p1->p_pfsflags & PF_FORK) == 0) 223 td2->td_frame->tf_eflags &= ~PSL_T; 224 225 /* 226 * Set registers for trampoline to user mode. Leave space for the 227 * return address on stack. These are the kernel mode register values. 228 */ 229 #ifdef PAE 230 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdpt); 231 #else 232 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir); 233 #endif 234 pcb2->pcb_edi = 0; 235 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */ 236 pcb2->pcb_ebp = 0; 237 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *); 238 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */ 239 pcb2->pcb_eip = (int)fork_trampoline; 240 pcb2->pcb_psl = PSL_KERNEL; /* ints disabled */ 241 /*- 242 * pcb2->pcb_dr*: cloned above. 243 * pcb2->pcb_savefpu: cloned above. 244 * pcb2->pcb_flags: cloned above. 245 * pcb2->pcb_onfault: cloned above (always NULL here?). 246 * pcb2->pcb_gs: cloned above. 247 * pcb2->pcb_ext: cleared below. 248 */ 249 250 /* 251 * XXX don't copy the i/o pages. this should probably be fixed. 252 */ 253 pcb2->pcb_ext = 0; 254 255 /* Copy the LDT, if necessary. */ 256 mtx_lock_spin(&dt_lock); 257 if (mdp2->md_ldt != NULL) { 258 if (flags & RFMEM) { 259 mdp2->md_ldt->ldt_refcnt++; 260 } else { 261 mdp2->md_ldt = user_ldt_alloc(mdp2, 262 mdp2->md_ldt->ldt_len); 263 if (mdp2->md_ldt == NULL) 264 panic("could not copy LDT"); 265 } 266 } 267 mtx_unlock_spin(&dt_lock); 268 269 /* Setup to release spin count in fork_exit(). */ 270 td2->td_md.md_spinlock_count = 1; 271 /* 272 * XXX XEN need to check on PSL_USER is handled 273 */ 274 td2->td_md.md_saved_flags = PSL_KERNEL | PSL_I; 275 /* 276 * Now, cpu_switch() can schedule the new process. 277 * pcb_esp is loaded pointing to the cpu_switch() stack frame 278 * containing the return address when exiting cpu_switch. 279 * This will normally be to fork_trampoline(), which will have 280 * %ebx loaded with the new proc's pointer. fork_trampoline() 281 * will set up a stack to call fork_return(p, frame); to complete 282 * the return to user-mode. 283 */ 284 } 285 286 /* 287 * Intercept the return address from a freshly forked process that has NOT 288 * been scheduled yet. 289 * 290 * This is needed to make kernel threads stay in kernel mode. 291 */ 292 void 293 cpu_set_fork_handler(td, func, arg) 294 struct thread *td; 295 void (*func)(void *); 296 void *arg; 297 { 298 /* 299 * Note that the trap frame follows the args, so the function 300 * is really called like this: func(arg, frame); 301 */ 302 td->td_pcb->pcb_esi = (int) func; /* function */ 303 td->td_pcb->pcb_ebx = (int) arg; /* first arg */ 304 } 305 306 void 307 cpu_exit(struct thread *td) 308 { 309 310 /* 311 * If this process has a custom LDT, release it. Reset pc->pcb_gs 312 * and %gs before we free it in case they refer to an LDT entry. 313 */ 314 mtx_lock_spin(&dt_lock); 315 if (td->td_proc->p_md.md_ldt) { 316 td->td_pcb->pcb_gs = _udatasel; 317 load_gs(_udatasel); 318 user_ldt_free(td); 319 } else 320 mtx_unlock_spin(&dt_lock); 321 } 322 323 void 324 cpu_thread_exit(struct thread *td) 325 { 326 327 #ifdef DEV_NPX 328 critical_enter(); 329 if (td == PCPU_GET(fpcurthread)) 330 npxdrop(); 331 critical_exit(); 332 #endif 333 334 /* Disable any hardware breakpoints. */ 335 if (td->td_pcb->pcb_flags & PCB_DBREGS) { 336 reset_dbregs(); 337 td->td_pcb->pcb_flags &= ~PCB_DBREGS; 338 } 339 } 340 341 void 342 cpu_thread_clean(struct thread *td) 343 { 344 struct pcb *pcb; 345 346 pcb = td->td_pcb; 347 if (pcb->pcb_ext != NULL) { 348 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */ 349 /* 350 * XXX do we need to move the TSS off the allocated pages 351 * before freeing them? (not done here) 352 */ 353 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext, 354 ctob(IOPAGES + 1)); 355 pcb->pcb_ext = NULL; 356 } 357 } 358 359 void 360 cpu_thread_swapin(struct thread *td) 361 { 362 } 363 364 void 365 cpu_thread_swapout(struct thread *td) 366 { 367 } 368 369 void 370 cpu_thread_alloc(struct thread *td) 371 { 372 373 td->td_pcb = (struct pcb *)(td->td_kstack + 374 td->td_kstack_pages * PAGE_SIZE) - 1; 375 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1; 376 td->td_pcb->pcb_ext = NULL; 377 td->td_pcb->pcb_save = &td->td_pcb->pcb_user_save; 378 } 379 380 void 381 cpu_thread_free(struct thread *td) 382 { 383 384 cpu_thread_clean(td); 385 } 386 387 void 388 cpu_set_syscall_retval(struct thread *td, int error) 389 { 390 391 switch (error) { 392 case 0: 393 td->td_frame->tf_eax = td->td_retval[0]; 394 td->td_frame->tf_edx = td->td_retval[1]; 395 td->td_frame->tf_eflags &= ~PSL_C; 396 break; 397 398 case ERESTART: 399 /* 400 * Reconstruct pc, assuming lcall $X,y is 7 bytes, int 401 * 0x80 is 2 bytes. We saved this in tf_err. 402 */ 403 td->td_frame->tf_eip -= td->td_frame->tf_err; 404 break; 405 406 case EJUSTRETURN: 407 break; 408 409 default: 410 if (td->td_proc->p_sysent->sv_errsize) { 411 if (error >= td->td_proc->p_sysent->sv_errsize) 412 error = -1; /* XXX */ 413 else 414 error = td->td_proc->p_sysent->sv_errtbl[error]; 415 } 416 td->td_frame->tf_eax = error; 417 td->td_frame->tf_eflags |= PSL_C; 418 break; 419 } 420 } 421 422 /* 423 * Initialize machine state (pcb and trap frame) for a new thread about to 424 * upcall. Put enough state in the new thread's PCB to get it to go back 425 * userret(), where we can intercept it again to set the return (upcall) 426 * Address and stack, along with those from upcals that are from other sources 427 * such as those generated in thread_userret() itself. 428 */ 429 void 430 cpu_set_upcall(struct thread *td, struct thread *td0) 431 { 432 struct pcb *pcb2; 433 434 /* Point the pcb to the top of the stack. */ 435 pcb2 = td->td_pcb; 436 437 /* 438 * Copy the upcall pcb. This loads kernel regs. 439 * Those not loaded individually below get their default 440 * values here. 441 */ 442 bcopy(td0->td_pcb, pcb2, sizeof(*pcb2)); 443 pcb2->pcb_flags &= ~(PCB_NPXINITDONE | PCB_NPXUSERINITDONE); 444 pcb2->pcb_save = &pcb2->pcb_user_save; 445 446 /* 447 * Create a new fresh stack for the new thread. 448 */ 449 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 450 451 /* If the current thread has the trap bit set (i.e. a debugger had 452 * single stepped the process to the system call), we need to clear 453 * the trap flag from the new frame. Otherwise, the new thread will 454 * receive a (likely unexpected) SIGTRAP when it executes the first 455 * instruction after returning to userland. 456 */ 457 td->td_frame->tf_eflags &= ~PSL_T; 458 459 /* 460 * Set registers for trampoline to user mode. Leave space for the 461 * return address on stack. These are the kernel mode register values. 462 */ 463 pcb2->pcb_edi = 0; 464 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */ 465 pcb2->pcb_ebp = 0; 466 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */ 467 pcb2->pcb_ebx = (int)td; /* trampoline arg */ 468 pcb2->pcb_eip = (int)fork_trampoline; 469 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */ 470 pcb2->pcb_gs = rgs(); 471 /* 472 * If we didn't copy the pcb, we'd need to do the following registers: 473 * pcb2->pcb_cr3: cloned above. 474 * pcb2->pcb_dr*: cloned above. 475 * pcb2->pcb_savefpu: cloned above. 476 * pcb2->pcb_flags: cloned above. 477 * pcb2->pcb_onfault: cloned above (always NULL here?). 478 * pcb2->pcb_gs: cloned above. 479 * pcb2->pcb_ext: cleared below. 480 */ 481 pcb2->pcb_ext = NULL; 482 483 /* Setup to release spin count in fork_exit(). */ 484 td->td_md.md_spinlock_count = 1; 485 td->td_md.md_saved_flags = PSL_KERNEL | PSL_I; 486 } 487 488 /* 489 * Set that machine state for performing an upcall that has to 490 * be done in thread_userret() so that those upcalls generated 491 * in thread_userret() itself can be done as well. 492 */ 493 void 494 cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg, 495 stack_t *stack) 496 { 497 498 /* 499 * Do any extra cleaning that needs to be done. 500 * The thread may have optional components 501 * that are not present in a fresh thread. 502 * This may be a recycled thread so make it look 503 * as though it's newly allocated. 504 */ 505 cpu_thread_clean(td); 506 507 /* 508 * Set the trap frame to point at the beginning of the uts 509 * function. 510 */ 511 td->td_frame->tf_ebp = 0; 512 td->td_frame->tf_esp = 513 (((int)stack->ss_sp + stack->ss_size - 4) & ~0x0f) - 4; 514 td->td_frame->tf_eip = (int)entry; 515 516 /* 517 * Pass the address of the mailbox for this kse to the uts 518 * function as a parameter on the stack. 519 */ 520 suword((void *)(td->td_frame->tf_esp + sizeof(void *)), 521 (int)arg); 522 } 523 524 int 525 cpu_set_user_tls(struct thread *td, void *tls_base) 526 { 527 struct segment_descriptor sd; 528 uint32_t base; 529 530 /* 531 * Construct a descriptor and store it in the pcb for 532 * the next context switch. Also store it in the gdt 533 * so that the load of tf_fs into %fs will activate it 534 * at return to userland. 535 */ 536 base = (uint32_t)tls_base; 537 sd.sd_lobase = base & 0xffffff; 538 sd.sd_hibase = (base >> 24) & 0xff; 539 sd.sd_lolimit = 0xffff; /* 4GB limit, wraps around */ 540 sd.sd_hilimit = 0xf; 541 sd.sd_type = SDT_MEMRWA; 542 sd.sd_dpl = SEL_UPL; 543 sd.sd_p = 1; 544 sd.sd_xx = 0; 545 sd.sd_def32 = 1; 546 sd.sd_gran = 1; 547 critical_enter(); 548 /* set %gs */ 549 td->td_pcb->pcb_gsd = sd; 550 if (td == curthread) { 551 PCPU_GET(fsgs_gdt)[1] = sd; 552 load_gs(GSEL(GUGS_SEL, SEL_UPL)); 553 } 554 critical_exit(); 555 return (0); 556 } 557 558 /* 559 * Convert kernel VA to physical address 560 */ 561 vm_paddr_t 562 kvtop(void *addr) 563 { 564 vm_paddr_t pa; 565 566 pa = pmap_kextract((vm_offset_t)addr); 567 if (pa == 0) 568 panic("kvtop: zero page frame"); 569 return (pa); 570 } 571 572 #ifdef SMP 573 static void 574 cpu_reset_proxy() 575 { 576 577 cpu_reset_proxy_active = 1; 578 while (cpu_reset_proxy_active == 1) 579 ; /* Wait for other cpu to see that we've started */ 580 stop_cpus((1<<cpu_reset_proxyid)); 581 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid); 582 DELAY(1000000); 583 cpu_reset_real(); 584 } 585 #endif 586 587 void 588 cpu_reset() 589 { 590 #ifdef XBOX 591 if (arch_i386_is_xbox) { 592 /* Kick the PIC16L, it can reboot the box */ 593 pic16l_reboot(); 594 for (;;); 595 } 596 #endif 597 598 #ifdef SMP 599 u_int cnt, map; 600 601 if (smp_active) { 602 map = PCPU_GET(other_cpus) & ~stopped_cpus; 603 if (map != 0) { 604 printf("cpu_reset: Stopping other CPUs\n"); 605 stop_cpus(map); 606 } 607 608 if (PCPU_GET(cpuid) != 0) { 609 cpu_reset_proxyid = PCPU_GET(cpuid); 610 cpustop_restartfunc = cpu_reset_proxy; 611 cpu_reset_proxy_active = 0; 612 printf("cpu_reset: Restarting BSP\n"); 613 614 /* Restart CPU #0. */ 615 /* XXX: restart_cpus(1 << 0); */ 616 atomic_store_rel_int(&started_cpus, (1 << 0)); 617 618 cnt = 0; 619 while (cpu_reset_proxy_active == 0 && cnt < 10000000) 620 cnt++; /* Wait for BSP to announce restart */ 621 if (cpu_reset_proxy_active == 0) 622 printf("cpu_reset: Failed to restart BSP\n"); 623 enable_intr(); 624 cpu_reset_proxy_active = 2; 625 626 while (1); 627 /* NOTREACHED */ 628 } 629 630 DELAY(1000000); 631 } 632 #endif 633 cpu_reset_real(); 634 /* NOTREACHED */ 635 } 636 637 static void 638 cpu_reset_real() 639 { 640 struct region_descriptor null_idt; 641 #ifndef PC98 642 int b; 643 #endif 644 645 disable_intr(); 646 #ifdef XEN 647 if (smp_processor_id() == 0) 648 HYPERVISOR_shutdown(SHUTDOWN_reboot); 649 else 650 HYPERVISOR_shutdown(SHUTDOWN_poweroff); 651 #endif 652 #ifdef CPU_ELAN 653 if (elan_mmcr != NULL) 654 elan_mmcr->RESCFG = 1; 655 #endif 656 657 if (cpu == CPU_GEODE1100) { 658 /* Attempt Geode's own reset */ 659 outl(0xcf8, 0x80009044ul); 660 outl(0xcfc, 0xf); 661 } 662 663 #ifdef PC98 664 /* 665 * Attempt to do a CPU reset via CPU reset port. 666 */ 667 if ((inb(0x35) & 0xa0) != 0xa0) { 668 outb(0x37, 0x0f); /* SHUT0 = 0. */ 669 outb(0x37, 0x0b); /* SHUT1 = 0. */ 670 } 671 outb(0xf0, 0x00); /* Reset. */ 672 #else 673 #if !defined(BROKEN_KEYBOARD_RESET) 674 /* 675 * Attempt to do a CPU reset via the keyboard controller, 676 * do not turn off GateA20, as any machine that fails 677 * to do the reset here would then end up in no man's land. 678 */ 679 outb(IO_KBD + 4, 0xFE); 680 DELAY(500000); /* wait 0.5 sec to see if that did it */ 681 #endif 682 683 /* 684 * Attempt to force a reset via the Reset Control register at 685 * I/O port 0xcf9. Bit 2 forces a system reset when it 686 * transitions from 0 to 1. Bit 1 selects the type of reset 687 * to attempt: 0 selects a "soft" reset, and 1 selects a 688 * "hard" reset. We try a "hard" reset. The first write sets 689 * bit 1 to select a "hard" reset and clears bit 2. The 690 * second write forces a 0 -> 1 transition in bit 2 to trigger 691 * a reset. 692 */ 693 outb(0xcf9, 0x2); 694 outb(0xcf9, 0x6); 695 DELAY(500000); /* wait 0.5 sec to see if that did it */ 696 697 /* 698 * Attempt to force a reset via the Fast A20 and Init register 699 * at I/O port 0x92. Bit 1 serves as an alternate A20 gate. 700 * Bit 0 asserts INIT# when set to 1. We are careful to only 701 * preserve bit 1 while setting bit 0. We also must clear bit 702 * 0 before setting it if it isn't already clear. 703 */ 704 b = inb(0x92); 705 if (b != 0xff) { 706 if ((b & 0x1) != 0) 707 outb(0x92, b & 0xfe); 708 outb(0x92, b | 0x1); 709 DELAY(500000); /* wait 0.5 sec to see if that did it */ 710 } 711 #endif /* PC98 */ 712 713 printf("No known reset method worked, attempting CPU shutdown\n"); 714 DELAY(1000000); /* wait 1 sec for printf to complete */ 715 716 /* Wipe the IDT. */ 717 null_idt.rd_limit = 0; 718 null_idt.rd_base = 0; 719 lidt(&null_idt); 720 721 /* "good night, sweet prince .... <THUNK!>" */ 722 breakpoint(); 723 724 /* NOTREACHED */ 725 while(1); 726 } 727 728 /* 729 * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-)) 730 */ 731 static void 732 sf_buf_init(void *arg) 733 { 734 struct sf_buf *sf_bufs; 735 vm_offset_t sf_base; 736 int i; 737 738 nsfbufs = NSFBUFS; 739 TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs); 740 741 sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask); 742 TAILQ_INIT(&sf_buf_freelist); 743 sf_base = kmem_alloc_nofault(kernel_map, nsfbufs * PAGE_SIZE); 744 sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP, 745 M_NOWAIT | M_ZERO); 746 for (i = 0; i < nsfbufs; i++) { 747 sf_bufs[i].kva = sf_base + i * PAGE_SIZE; 748 TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry); 749 } 750 sf_buf_alloc_want = 0; 751 mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF); 752 } 753 754 /* 755 * Invalidate the cache lines that may belong to the page, if 756 * (possibly old) mapping of the page by sf buffer exists. Returns 757 * TRUE when mapping was found and cache invalidated. 758 */ 759 boolean_t 760 sf_buf_invalidate_cache(vm_page_t m) 761 { 762 struct sf_head *hash_list; 763 struct sf_buf *sf; 764 boolean_t ret; 765 766 hash_list = &sf_buf_active[SF_BUF_HASH(m)]; 767 ret = FALSE; 768 mtx_lock(&sf_buf_lock); 769 LIST_FOREACH(sf, hash_list, list_entry) { 770 if (sf->m == m) { 771 /* 772 * Use pmap_qenter to update the pte for 773 * existing mapping, in particular, the PAT 774 * settings are recalculated. 775 */ 776 pmap_qenter(sf->kva, &m, 1); 777 pmap_invalidate_cache_range(sf->kva, sf->kva + 778 PAGE_SIZE); 779 ret = TRUE; 780 break; 781 } 782 } 783 mtx_unlock(&sf_buf_lock); 784 return (ret); 785 } 786 787 /* 788 * Get an sf_buf from the freelist. May block if none are available. 789 */ 790 struct sf_buf * 791 sf_buf_alloc(struct vm_page *m, int flags) 792 { 793 pt_entry_t opte, *ptep; 794 struct sf_head *hash_list; 795 struct sf_buf *sf; 796 #ifdef SMP 797 cpumask_t cpumask, other_cpus; 798 #endif 799 int error; 800 801 KASSERT(curthread->td_pinned > 0 || (flags & SFB_CPUPRIVATE) == 0, 802 ("sf_buf_alloc(SFB_CPUPRIVATE): curthread not pinned")); 803 hash_list = &sf_buf_active[SF_BUF_HASH(m)]; 804 mtx_lock(&sf_buf_lock); 805 LIST_FOREACH(sf, hash_list, list_entry) { 806 if (sf->m == m) { 807 sf->ref_count++; 808 if (sf->ref_count == 1) { 809 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 810 nsfbufsused++; 811 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 812 } 813 #ifdef SMP 814 goto shootdown; 815 #else 816 goto done; 817 #endif 818 } 819 } 820 while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) { 821 if (flags & SFB_NOWAIT) 822 goto done; 823 sf_buf_alloc_want++; 824 mbstat.sf_allocwait++; 825 error = msleep(&sf_buf_freelist, &sf_buf_lock, 826 (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0); 827 sf_buf_alloc_want--; 828 829 /* 830 * If we got a signal, don't risk going back to sleep. 831 */ 832 if (error) 833 goto done; 834 } 835 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 836 if (sf->m != NULL) 837 LIST_REMOVE(sf, list_entry); 838 LIST_INSERT_HEAD(hash_list, sf, list_entry); 839 sf->ref_count = 1; 840 sf->m = m; 841 nsfbufsused++; 842 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 843 844 /* 845 * Update the sf_buf's virtual-to-physical mapping, flushing the 846 * virtual address from the TLB. Since the reference count for 847 * the sf_buf's old mapping was zero, that mapping is not 848 * currently in use. Consequently, there is no need to exchange 849 * the old and new PTEs atomically, even under PAE. 850 */ 851 ptep = vtopte(sf->kva); 852 opte = *ptep; 853 #ifdef XEN 854 PT_SET_MA(sf->kva, xpmap_ptom(VM_PAGE_TO_PHYS(m)) | pgeflag 855 | PG_RW | PG_V | pmap_cache_bits(m->md.pat_mode, 0)); 856 #else 857 *ptep = VM_PAGE_TO_PHYS(m) | pgeflag | PG_RW | PG_V | 858 pmap_cache_bits(m->md.pat_mode, 0); 859 #endif 860 861 /* 862 * Avoid unnecessary TLB invalidations: If the sf_buf's old 863 * virtual-to-physical mapping was not used, then any processor 864 * that has invalidated the sf_buf's virtual address from its TLB 865 * since the last used mapping need not invalidate again. 866 */ 867 #ifdef SMP 868 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A)) 869 sf->cpumask = 0; 870 shootdown: 871 sched_pin(); 872 cpumask = PCPU_GET(cpumask); 873 if ((sf->cpumask & cpumask) == 0) { 874 sf->cpumask |= cpumask; 875 invlpg(sf->kva); 876 } 877 if ((flags & SFB_CPUPRIVATE) == 0) { 878 other_cpus = PCPU_GET(other_cpus) & ~sf->cpumask; 879 if (other_cpus != 0) { 880 sf->cpumask |= other_cpus; 881 smp_masked_invlpg(other_cpus, sf->kva); 882 } 883 } 884 sched_unpin(); 885 #else 886 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A)) 887 pmap_invalidate_page(kernel_pmap, sf->kva); 888 #endif 889 done: 890 mtx_unlock(&sf_buf_lock); 891 return (sf); 892 } 893 894 /* 895 * Remove a reference from the given sf_buf, adding it to the free 896 * list when its reference count reaches zero. A freed sf_buf still, 897 * however, retains its virtual-to-physical mapping until it is 898 * recycled or reactivated by sf_buf_alloc(9). 899 */ 900 void 901 sf_buf_free(struct sf_buf *sf) 902 { 903 904 mtx_lock(&sf_buf_lock); 905 sf->ref_count--; 906 if (sf->ref_count == 0) { 907 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry); 908 nsfbufsused--; 909 #ifdef XEN 910 /* 911 * Xen doesn't like having dangling R/W mappings 912 */ 913 pmap_qremove(sf->kva, 1); 914 sf->m = NULL; 915 LIST_REMOVE(sf, list_entry); 916 #endif 917 if (sf_buf_alloc_want > 0) 918 wakeup_one(&sf_buf_freelist); 919 } 920 mtx_unlock(&sf_buf_lock); 921 } 922 923 /* 924 * Software interrupt handler for queued VM system processing. 925 */ 926 void 927 swi_vm(void *dummy) 928 { 929 if (busdma_swi_pending != 0) 930 busdma_swi(); 931 } 932 933 /* 934 * Tell whether this address is in some physical memory region. 935 * Currently used by the kernel coredump code in order to avoid 936 * dumping the ``ISA memory hole'' which could cause indefinite hangs, 937 * or other unpredictable behaviour. 938 */ 939 940 int 941 is_physical_memory(vm_paddr_t addr) 942 { 943 944 #ifdef DEV_ISA 945 /* The ISA ``memory hole''. */ 946 if (addr >= 0xa0000 && addr < 0x100000) 947 return 0; 948 #endif 949 950 /* 951 * stuff other tests for known memory-mapped devices (PCI?) 952 * here 953 */ 954 955 return 1; 956 } 957