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 #ifdef DEV_NPX 154 register_t savecrit; 155 #endif 156 157 p1 = td1->td_proc; 158 if ((flags & RFPROC) == 0) { 159 if ((flags & RFMEM) == 0) { 160 /* unshare user LDT */ 161 struct mdproc *mdp1 = &p1->p_md; 162 struct proc_ldt *pldt, *pldt1; 163 164 mtx_lock_spin(&dt_lock); 165 if ((pldt1 = mdp1->md_ldt) != NULL && 166 pldt1->ldt_refcnt > 1) { 167 pldt = user_ldt_alloc(mdp1, pldt1->ldt_len); 168 if (pldt == NULL) 169 panic("could not copy LDT"); 170 mdp1->md_ldt = pldt; 171 set_user_ldt(mdp1); 172 user_ldt_deref(pldt1); 173 } else 174 mtx_unlock_spin(&dt_lock); 175 } 176 return; 177 } 178 179 /* Ensure that td1's pcb is up to date. */ 180 if (td1 == curthread) 181 td1->td_pcb->pcb_gs = rgs(); 182 #ifdef DEV_NPX 183 savecrit = intr_disable(); 184 if (PCPU_GET(fpcurthread) == td1) 185 npxsave(td1->td_pcb->pcb_save); 186 intr_restore(savecrit); 187 #endif 188 189 /* Point the pcb to the top of the stack */ 190 pcb2 = (struct pcb *)(td2->td_kstack + 191 td2->td_kstack_pages * PAGE_SIZE) - 1; 192 td2->td_pcb = pcb2; 193 194 /* Copy td1's pcb */ 195 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 196 197 /* Properly initialize pcb_save */ 198 pcb2->pcb_save = &pcb2->pcb_user_save; 199 200 /* Point mdproc and then copy over td1's contents */ 201 mdp2 = &p2->p_md; 202 bcopy(&p1->p_md, mdp2, sizeof(*mdp2)); 203 204 /* 205 * Create a new fresh stack for the new process. 206 * Copy the trap frame for the return to user mode as if from a 207 * syscall. This copies most of the user mode register values. 208 * The -16 is so we can expand the trapframe if we go to vm86. 209 */ 210 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1; 211 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe)); 212 213 td2->td_frame->tf_eax = 0; /* Child returns zero */ 214 td2->td_frame->tf_eflags &= ~PSL_C; /* success */ 215 td2->td_frame->tf_edx = 1; 216 217 /* 218 * If the parent process has the trap bit set (i.e. a debugger had 219 * single stepped the process to the system call), we need to clear 220 * the trap flag from the new frame unless the debugger had set PF_FORK 221 * on the parent. Otherwise, the child will receive a (likely 222 * unexpected) SIGTRAP when it executes the first instruction after 223 * returning to userland. 224 */ 225 if ((p1->p_pfsflags & PF_FORK) == 0) 226 td2->td_frame->tf_eflags &= ~PSL_T; 227 228 /* 229 * Set registers for trampoline to user mode. Leave space for the 230 * return address on stack. These are the kernel mode register values. 231 */ 232 #ifdef PAE 233 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdpt); 234 #else 235 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir); 236 #endif 237 pcb2->pcb_edi = 0; 238 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */ 239 pcb2->pcb_ebp = 0; 240 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *); 241 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */ 242 pcb2->pcb_eip = (int)fork_trampoline; 243 pcb2->pcb_psl = PSL_KERNEL; /* ints disabled */ 244 /*- 245 * pcb2->pcb_dr*: cloned above. 246 * pcb2->pcb_savefpu: cloned above. 247 * pcb2->pcb_flags: cloned above. 248 * pcb2->pcb_onfault: cloned above (always NULL here?). 249 * pcb2->pcb_gs: cloned above. 250 * pcb2->pcb_ext: cleared below. 251 */ 252 253 /* 254 * XXX don't copy the i/o pages. this should probably be fixed. 255 */ 256 pcb2->pcb_ext = 0; 257 258 /* Copy the LDT, if necessary. */ 259 mtx_lock_spin(&dt_lock); 260 if (mdp2->md_ldt != NULL) { 261 if (flags & RFMEM) { 262 mdp2->md_ldt->ldt_refcnt++; 263 } else { 264 mdp2->md_ldt = user_ldt_alloc(mdp2, 265 mdp2->md_ldt->ldt_len); 266 if (mdp2->md_ldt == NULL) 267 panic("could not copy LDT"); 268 } 269 } 270 mtx_unlock_spin(&dt_lock); 271 272 /* Setup to release spin count in fork_exit(). */ 273 td2->td_md.md_spinlock_count = 1; 274 /* 275 * XXX XEN need to check on PSL_USER is handled 276 */ 277 td2->td_md.md_saved_flags = PSL_KERNEL | PSL_I; 278 /* 279 * Now, cpu_switch() can schedule the new process. 280 * pcb_esp is loaded pointing to the cpu_switch() stack frame 281 * containing the return address when exiting cpu_switch. 282 * This will normally be to fork_trampoline(), which will have 283 * %ebx loaded with the new proc's pointer. fork_trampoline() 284 * will set up a stack to call fork_return(p, frame); to complete 285 * the return to user-mode. 286 */ 287 } 288 289 /* 290 * Intercept the return address from a freshly forked process that has NOT 291 * been scheduled yet. 292 * 293 * This is needed to make kernel threads stay in kernel mode. 294 */ 295 void 296 cpu_set_fork_handler(td, func, arg) 297 struct thread *td; 298 void (*func)(void *); 299 void *arg; 300 { 301 /* 302 * Note that the trap frame follows the args, so the function 303 * is really called like this: func(arg, frame); 304 */ 305 td->td_pcb->pcb_esi = (int) func; /* function */ 306 td->td_pcb->pcb_ebx = (int) arg; /* first arg */ 307 } 308 309 void 310 cpu_exit(struct thread *td) 311 { 312 313 /* 314 * If this process has a custom LDT, release it. Reset pc->pcb_gs 315 * and %gs before we free it in case they refer to an LDT entry. 316 */ 317 mtx_lock_spin(&dt_lock); 318 if (td->td_proc->p_md.md_ldt) { 319 td->td_pcb->pcb_gs = _udatasel; 320 load_gs(_udatasel); 321 user_ldt_free(td); 322 } else 323 mtx_unlock_spin(&dt_lock); 324 } 325 326 void 327 cpu_thread_exit(struct thread *td) 328 { 329 330 #ifdef DEV_NPX 331 if (td == PCPU_GET(fpcurthread)) 332 npxdrop(); 333 #endif 334 335 /* Disable any hardware breakpoints. */ 336 if (td->td_pcb->pcb_flags & PCB_DBREGS) { 337 reset_dbregs(); 338 td->td_pcb->pcb_flags &= ~PCB_DBREGS; 339 } 340 } 341 342 void 343 cpu_thread_clean(struct thread *td) 344 { 345 struct pcb *pcb; 346 347 pcb = td->td_pcb; 348 if (pcb->pcb_ext != NULL) { 349 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */ 350 /* 351 * XXX do we need to move the TSS off the allocated pages 352 * before freeing them? (not done here) 353 */ 354 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext, 355 ctob(IOPAGES + 1)); 356 pcb->pcb_ext = NULL; 357 } 358 } 359 360 void 361 cpu_thread_swapin(struct thread *td) 362 { 363 } 364 365 void 366 cpu_thread_swapout(struct thread *td) 367 { 368 } 369 370 void 371 cpu_thread_alloc(struct thread *td) 372 { 373 374 td->td_pcb = (struct pcb *)(td->td_kstack + 375 td->td_kstack_pages * PAGE_SIZE) - 1; 376 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1; 377 td->td_pcb->pcb_ext = NULL; 378 td->td_pcb->pcb_save = &td->td_pcb->pcb_user_save; 379 } 380 381 void 382 cpu_thread_free(struct thread *td) 383 { 384 385 cpu_thread_clean(td); 386 } 387 388 void 389 cpu_set_syscall_retval(struct thread *td, int error) 390 { 391 392 switch (error) { 393 case 0: 394 td->td_frame->tf_eax = td->td_retval[0]; 395 td->td_frame->tf_edx = td->td_retval[1]; 396 td->td_frame->tf_eflags &= ~PSL_C; 397 break; 398 399 case ERESTART: 400 /* 401 * Reconstruct pc, assuming lcall $X,y is 7 bytes, int 402 * 0x80 is 2 bytes. We saved this in tf_err. 403 */ 404 td->td_frame->tf_eip -= td->td_frame->tf_err; 405 break; 406 407 case EJUSTRETURN: 408 break; 409 410 default: 411 if (td->td_proc->p_sysent->sv_errsize) { 412 if (error >= td->td_proc->p_sysent->sv_errsize) 413 error = -1; /* XXX */ 414 else 415 error = td->td_proc->p_sysent->sv_errtbl[error]; 416 } 417 td->td_frame->tf_eax = error; 418 td->td_frame->tf_eflags |= PSL_C; 419 break; 420 } 421 } 422 423 /* 424 * Initialize machine state (pcb and trap frame) for a new thread about to 425 * upcall. Put enough state in the new thread's PCB to get it to go back 426 * userret(), where we can intercept it again to set the return (upcall) 427 * Address and stack, along with those from upcals that are from other sources 428 * such as those generated in thread_userret() itself. 429 */ 430 void 431 cpu_set_upcall(struct thread *td, struct thread *td0) 432 { 433 struct pcb *pcb2; 434 435 /* Point the pcb to the top of the stack. */ 436 pcb2 = td->td_pcb; 437 438 /* 439 * Copy the upcall pcb. This loads kernel regs. 440 * Those not loaded individually below get their default 441 * values here. 442 */ 443 bcopy(td0->td_pcb, pcb2, sizeof(*pcb2)); 444 pcb2->pcb_flags &= ~(PCB_NPXTRAP|PCB_NPXINITDONE|PCB_NPXUSERINITDONE); 445 pcb2->pcb_save = &pcb2->pcb_user_save; 446 447 /* 448 * Create a new fresh stack for the new thread. 449 */ 450 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 451 452 /* If the current thread has the trap bit set (i.e. a debugger had 453 * single stepped the process to the system call), we need to clear 454 * the trap flag from the new frame. Otherwise, the new thread will 455 * receive a (likely unexpected) SIGTRAP when it executes the first 456 * instruction after returning to userland. 457 */ 458 td->td_frame->tf_eflags &= ~PSL_T; 459 460 /* 461 * Set registers for trampoline to user mode. Leave space for the 462 * return address on stack. These are the kernel mode register values. 463 */ 464 pcb2->pcb_edi = 0; 465 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */ 466 pcb2->pcb_ebp = 0; 467 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */ 468 pcb2->pcb_ebx = (int)td; /* trampoline arg */ 469 pcb2->pcb_eip = (int)fork_trampoline; 470 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */ 471 pcb2->pcb_gs = rgs(); 472 /* 473 * If we didn't copy the pcb, we'd need to do the following registers: 474 * pcb2->pcb_cr3: cloned above. 475 * pcb2->pcb_dr*: cloned above. 476 * pcb2->pcb_savefpu: cloned above. 477 * pcb2->pcb_flags: cloned above. 478 * pcb2->pcb_onfault: cloned above (always NULL here?). 479 * pcb2->pcb_gs: cloned above. 480 * pcb2->pcb_ext: cleared below. 481 */ 482 pcb2->pcb_ext = NULL; 483 484 /* Setup to release spin count in fork_exit(). */ 485 td->td_md.md_spinlock_count = 1; 486 td->td_md.md_saved_flags = PSL_KERNEL | PSL_I; 487 } 488 489 /* 490 * Set that machine state for performing an upcall that has to 491 * be done in thread_userret() so that those upcalls generated 492 * in thread_userret() itself can be done as well. 493 */ 494 void 495 cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg, 496 stack_t *stack) 497 { 498 499 /* 500 * Do any extra cleaning that needs to be done. 501 * The thread may have optional components 502 * that are not present in a fresh thread. 503 * This may be a recycled thread so make it look 504 * as though it's newly allocated. 505 */ 506 cpu_thread_clean(td); 507 508 /* 509 * Set the trap frame to point at the beginning of the uts 510 * function. 511 */ 512 td->td_frame->tf_ebp = 0; 513 td->td_frame->tf_esp = 514 (((int)stack->ss_sp + stack->ss_size - 4) & ~0x0f) - 4; 515 td->td_frame->tf_eip = (int)entry; 516 517 /* 518 * Pass the address of the mailbox for this kse to the uts 519 * function as a parameter on the stack. 520 */ 521 suword((void *)(td->td_frame->tf_esp + sizeof(void *)), 522 (int)arg); 523 } 524 525 int 526 cpu_set_user_tls(struct thread *td, void *tls_base) 527 { 528 struct segment_descriptor sd; 529 uint32_t base; 530 531 /* 532 * Construct a descriptor and store it in the pcb for 533 * the next context switch. Also store it in the gdt 534 * so that the load of tf_fs into %fs will activate it 535 * at return to userland. 536 */ 537 base = (uint32_t)tls_base; 538 sd.sd_lobase = base & 0xffffff; 539 sd.sd_hibase = (base >> 24) & 0xff; 540 sd.sd_lolimit = 0xffff; /* 4GB limit, wraps around */ 541 sd.sd_hilimit = 0xf; 542 sd.sd_type = SDT_MEMRWA; 543 sd.sd_dpl = SEL_UPL; 544 sd.sd_p = 1; 545 sd.sd_xx = 0; 546 sd.sd_def32 = 1; 547 sd.sd_gran = 1; 548 critical_enter(); 549 /* set %gs */ 550 td->td_pcb->pcb_gsd = sd; 551 if (td == curthread) { 552 PCPU_GET(fsgs_gdt)[1] = sd; 553 load_gs(GSEL(GUGS_SEL, SEL_UPL)); 554 } 555 critical_exit(); 556 return (0); 557 } 558 559 /* 560 * Convert kernel VA to physical address 561 */ 562 vm_paddr_t 563 kvtop(void *addr) 564 { 565 vm_paddr_t pa; 566 567 pa = pmap_kextract((vm_offset_t)addr); 568 if (pa == 0) 569 panic("kvtop: zero page frame"); 570 return (pa); 571 } 572 573 #ifdef SMP 574 static void 575 cpu_reset_proxy() 576 { 577 578 cpu_reset_proxy_active = 1; 579 while (cpu_reset_proxy_active == 1) 580 ; /* Wait for other cpu to see that we've started */ 581 stop_cpus((1<<cpu_reset_proxyid)); 582 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid); 583 DELAY(1000000); 584 cpu_reset_real(); 585 } 586 #endif 587 588 void 589 cpu_reset() 590 { 591 #ifdef XBOX 592 if (arch_i386_is_xbox) { 593 /* Kick the PIC16L, it can reboot the box */ 594 pic16l_reboot(); 595 for (;;); 596 } 597 #endif 598 599 #ifdef SMP 600 u_int cnt, map; 601 602 if (smp_active) { 603 map = PCPU_GET(other_cpus) & ~stopped_cpus; 604 if (map != 0) { 605 printf("cpu_reset: Stopping other CPUs\n"); 606 stop_cpus(map); 607 } 608 609 if (PCPU_GET(cpuid) != 0) { 610 cpu_reset_proxyid = PCPU_GET(cpuid); 611 cpustop_restartfunc = cpu_reset_proxy; 612 cpu_reset_proxy_active = 0; 613 printf("cpu_reset: Restarting BSP\n"); 614 615 /* Restart CPU #0. */ 616 /* XXX: restart_cpus(1 << 0); */ 617 atomic_store_rel_int(&started_cpus, (1 << 0)); 618 619 cnt = 0; 620 while (cpu_reset_proxy_active == 0 && cnt < 10000000) 621 cnt++; /* Wait for BSP to announce restart */ 622 if (cpu_reset_proxy_active == 0) 623 printf("cpu_reset: Failed to restart BSP\n"); 624 enable_intr(); 625 cpu_reset_proxy_active = 2; 626 627 while (1); 628 /* NOTREACHED */ 629 } 630 631 DELAY(1000000); 632 } 633 #endif 634 cpu_reset_real(); 635 /* NOTREACHED */ 636 } 637 638 static void 639 cpu_reset_real() 640 { 641 struct region_descriptor null_idt; 642 #ifndef PC98 643 int b; 644 #endif 645 646 disable_intr(); 647 #ifdef XEN 648 if (smp_processor_id() == 0) 649 HYPERVISOR_shutdown(SHUTDOWN_reboot); 650 else 651 HYPERVISOR_shutdown(SHUTDOWN_poweroff); 652 #endif 653 #ifdef CPU_ELAN 654 if (elan_mmcr != NULL) 655 elan_mmcr->RESCFG = 1; 656 #endif 657 658 if (cpu == CPU_GEODE1100) { 659 /* Attempt Geode's own reset */ 660 outl(0xcf8, 0x80009044ul); 661 outl(0xcfc, 0xf); 662 } 663 664 #ifdef PC98 665 /* 666 * Attempt to do a CPU reset via CPU reset port. 667 */ 668 if ((inb(0x35) & 0xa0) != 0xa0) { 669 outb(0x37, 0x0f); /* SHUT0 = 0. */ 670 outb(0x37, 0x0b); /* SHUT1 = 0. */ 671 } 672 outb(0xf0, 0x00); /* Reset. */ 673 #else 674 #if !defined(BROKEN_KEYBOARD_RESET) 675 /* 676 * Attempt to do a CPU reset via the keyboard controller, 677 * do not turn off GateA20, as any machine that fails 678 * to do the reset here would then end up in no man's land. 679 */ 680 outb(IO_KBD + 4, 0xFE); 681 DELAY(500000); /* wait 0.5 sec to see if that did it */ 682 #endif 683 684 /* 685 * Attempt to force a reset via the Reset Control register at 686 * I/O port 0xcf9. Bit 2 forces a system reset when it 687 * transitions from 0 to 1. Bit 1 selects the type of reset 688 * to attempt: 0 selects a "soft" reset, and 1 selects a 689 * "hard" reset. We try a "hard" reset. The first write sets 690 * bit 1 to select a "hard" reset and clears bit 2. The 691 * second write forces a 0 -> 1 transition in bit 2 to trigger 692 * a reset. 693 */ 694 outb(0xcf9, 0x2); 695 outb(0xcf9, 0x6); 696 DELAY(500000); /* wait 0.5 sec to see if that did it */ 697 698 /* 699 * Attempt to force a reset via the Fast A20 and Init register 700 * at I/O port 0x92. Bit 1 serves as an alternate A20 gate. 701 * Bit 0 asserts INIT# when set to 1. We are careful to only 702 * preserve bit 1 while setting bit 0. We also must clear bit 703 * 0 before setting it if it isn't already clear. 704 */ 705 b = inb(0x92); 706 if (b != 0xff) { 707 if ((b & 0x1) != 0) 708 outb(0x92, b & 0xfe); 709 outb(0x92, b | 0x1); 710 DELAY(500000); /* wait 0.5 sec to see if that did it */ 711 } 712 #endif /* PC98 */ 713 714 printf("No known reset method worked, attempting CPU shutdown\n"); 715 DELAY(1000000); /* wait 1 sec for printf to complete */ 716 717 /* Wipe the IDT. */ 718 null_idt.rd_limit = 0; 719 null_idt.rd_base = 0; 720 lidt(&null_idt); 721 722 /* "good night, sweet prince .... <THUNK!>" */ 723 breakpoint(); 724 725 /* NOTREACHED */ 726 while(1); 727 } 728 729 /* 730 * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-)) 731 */ 732 static void 733 sf_buf_init(void *arg) 734 { 735 struct sf_buf *sf_bufs; 736 vm_offset_t sf_base; 737 int i; 738 739 nsfbufs = NSFBUFS; 740 TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs); 741 742 sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask); 743 TAILQ_INIT(&sf_buf_freelist); 744 sf_base = kmem_alloc_nofault(kernel_map, nsfbufs * PAGE_SIZE); 745 sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP, 746 M_NOWAIT | M_ZERO); 747 for (i = 0; i < nsfbufs; i++) { 748 sf_bufs[i].kva = sf_base + i * PAGE_SIZE; 749 TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry); 750 } 751 sf_buf_alloc_want = 0; 752 mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF); 753 } 754 755 /* 756 * Invalidate the cache lines that may belong to the page, if 757 * (possibly old) mapping of the page by sf buffer exists. Returns 758 * TRUE when mapping was found and cache invalidated. 759 */ 760 boolean_t 761 sf_buf_invalidate_cache(vm_page_t m) 762 { 763 struct sf_head *hash_list; 764 struct sf_buf *sf; 765 boolean_t ret; 766 767 hash_list = &sf_buf_active[SF_BUF_HASH(m)]; 768 ret = FALSE; 769 mtx_lock(&sf_buf_lock); 770 LIST_FOREACH(sf, hash_list, list_entry) { 771 if (sf->m == m) { 772 /* 773 * Use pmap_qenter to update the pte for 774 * existing mapping, in particular, the PAT 775 * settings are recalculated. 776 */ 777 pmap_qenter(sf->kva, &m, 1); 778 pmap_invalidate_cache_range(sf->kva, sf->kva + 779 PAGE_SIZE); 780 ret = TRUE; 781 break; 782 } 783 } 784 mtx_unlock(&sf_buf_lock); 785 return (ret); 786 } 787 788 /* 789 * Get an sf_buf from the freelist. May block if none are available. 790 */ 791 struct sf_buf * 792 sf_buf_alloc(struct vm_page *m, int flags) 793 { 794 pt_entry_t opte, *ptep; 795 struct sf_head *hash_list; 796 struct sf_buf *sf; 797 #ifdef SMP 798 cpumask_t cpumask, other_cpus; 799 #endif 800 int error; 801 802 KASSERT(curthread->td_pinned > 0 || (flags & SFB_CPUPRIVATE) == 0, 803 ("sf_buf_alloc(SFB_CPUPRIVATE): curthread not pinned")); 804 hash_list = &sf_buf_active[SF_BUF_HASH(m)]; 805 mtx_lock(&sf_buf_lock); 806 LIST_FOREACH(sf, hash_list, list_entry) { 807 if (sf->m == m) { 808 sf->ref_count++; 809 if (sf->ref_count == 1) { 810 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 811 nsfbufsused++; 812 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 813 } 814 #ifdef SMP 815 goto shootdown; 816 #else 817 goto done; 818 #endif 819 } 820 } 821 while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) { 822 if (flags & SFB_NOWAIT) 823 goto done; 824 sf_buf_alloc_want++; 825 mbstat.sf_allocwait++; 826 error = msleep(&sf_buf_freelist, &sf_buf_lock, 827 (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0); 828 sf_buf_alloc_want--; 829 830 /* 831 * If we got a signal, don't risk going back to sleep. 832 */ 833 if (error) 834 goto done; 835 } 836 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 837 if (sf->m != NULL) 838 LIST_REMOVE(sf, list_entry); 839 LIST_INSERT_HEAD(hash_list, sf, list_entry); 840 sf->ref_count = 1; 841 sf->m = m; 842 nsfbufsused++; 843 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 844 845 /* 846 * Update the sf_buf's virtual-to-physical mapping, flushing the 847 * virtual address from the TLB. Since the reference count for 848 * the sf_buf's old mapping was zero, that mapping is not 849 * currently in use. Consequently, there is no need to exchange 850 * the old and new PTEs atomically, even under PAE. 851 */ 852 ptep = vtopte(sf->kva); 853 opte = *ptep; 854 #ifdef XEN 855 PT_SET_MA(sf->kva, xpmap_ptom(VM_PAGE_TO_PHYS(m)) | pgeflag 856 | PG_RW | PG_V | pmap_cache_bits(m->md.pat_mode, 0)); 857 #else 858 *ptep = VM_PAGE_TO_PHYS(m) | pgeflag | PG_RW | PG_V | 859 pmap_cache_bits(m->md.pat_mode, 0); 860 #endif 861 862 /* 863 * Avoid unnecessary TLB invalidations: If the sf_buf's old 864 * virtual-to-physical mapping was not used, then any processor 865 * that has invalidated the sf_buf's virtual address from its TLB 866 * since the last used mapping need not invalidate again. 867 */ 868 #ifdef SMP 869 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A)) 870 sf->cpumask = 0; 871 shootdown: 872 sched_pin(); 873 cpumask = PCPU_GET(cpumask); 874 if ((sf->cpumask & cpumask) == 0) { 875 sf->cpumask |= cpumask; 876 invlpg(sf->kva); 877 } 878 if ((flags & SFB_CPUPRIVATE) == 0) { 879 other_cpus = PCPU_GET(other_cpus) & ~sf->cpumask; 880 if (other_cpus != 0) { 881 sf->cpumask |= other_cpus; 882 smp_masked_invlpg(other_cpus, sf->kva); 883 } 884 } 885 sched_unpin(); 886 #else 887 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A)) 888 pmap_invalidate_page(kernel_pmap, sf->kva); 889 #endif 890 done: 891 mtx_unlock(&sf_buf_lock); 892 return (sf); 893 } 894 895 /* 896 * Remove a reference from the given sf_buf, adding it to the free 897 * list when its reference count reaches zero. A freed sf_buf still, 898 * however, retains its virtual-to-physical mapping until it is 899 * recycled or reactivated by sf_buf_alloc(9). 900 */ 901 void 902 sf_buf_free(struct sf_buf *sf) 903 { 904 905 mtx_lock(&sf_buf_lock); 906 sf->ref_count--; 907 if (sf->ref_count == 0) { 908 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry); 909 nsfbufsused--; 910 #ifdef XEN 911 /* 912 * Xen doesn't like having dangling R/W mappings 913 */ 914 pmap_qremove(sf->kva, 1); 915 sf->m = NULL; 916 LIST_REMOVE(sf, list_entry); 917 #endif 918 if (sf_buf_alloc_want > 0) 919 wakeup_one(&sf_buf_freelist); 920 } 921 mtx_unlock(&sf_buf_lock); 922 } 923 924 /* 925 * Software interrupt handler for queued VM system processing. 926 */ 927 void 928 swi_vm(void *dummy) 929 { 930 if (busdma_swi_pending != 0) 931 busdma_swi(); 932 } 933 934 /* 935 * Tell whether this address is in some physical memory region. 936 * Currently used by the kernel coredump code in order to avoid 937 * dumping the ``ISA memory hole'' which could cause indefinite hangs, 938 * or other unpredictable behaviour. 939 */ 940 941 int 942 is_physical_memory(vm_paddr_t addr) 943 { 944 945 #ifdef DEV_ISA 946 /* The ISA ``memory hole''. */ 947 if (addr >= 0xa0000 && addr < 0x100000) 948 return 0; 949 #endif 950 951 /* 952 * stuff other tests for known memory-mapped devices (PCI?) 953 * here 954 */ 955 956 return 1; 957 } 958