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 109CTASSERT((struct thread **)OFFSETOF_CURTHREAD == 110 &((struct pcpu *)NULL)->pc_curthread); 111CTASSERT((struct pcb **)OFFSETOF_CURPCB == &((struct pcpu *)NULL)->pc_curpcb); 112 113static void cpu_reset_real(void); 114#ifdef SMP 115static void cpu_reset_proxy(void); 116static u_int cpu_reset_proxyid; 117static volatile u_int cpu_reset_proxy_active; 118#endif 119static void sf_buf_init(void *arg); 120SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL); 121 122LIST_HEAD(sf_head, sf_buf); 123 124/* 125 * A hash table of active sendfile(2) buffers 126 */ 127static struct sf_head *sf_buf_active; 128static u_long sf_buf_hashmask; 129 130#define SF_BUF_HASH(m) (((m) - vm_page_array) & sf_buf_hashmask) 131 132static TAILQ_HEAD(, sf_buf) sf_buf_freelist; 133static u_int sf_buf_alloc_want; 134 135/* 136 * A lock used to synchronize access to the hash table and free list 137 */ 138static struct mtx sf_buf_lock; 139 140extern int _ucodesel, _udatasel; 141 142/* 143 * Finish a fork operation, with process p2 nearly set up. 144 * Copy and update the pcb, set up the stack so that the child 145 * ready to run and return to user mode. 146 */ 147void 148cpu_fork(td1, p2, td2, flags) 149 register struct thread *td1; 150 register struct proc *p2; 151 struct thread *td2; 152 int flags; 153{ 154 register struct proc *p1; 155 struct pcb *pcb2; 156 struct mdproc *mdp2; 157 158 p1 = td1->td_proc; 159 if ((flags & RFPROC) == 0) { 160 if ((flags & RFMEM) == 0) { 161 /* unshare user LDT */ 162 struct mdproc *mdp1 = &p1->p_md; 163 struct proc_ldt *pldt, *pldt1; 164 165 mtx_lock_spin(&dt_lock); 166 if ((pldt1 = mdp1->md_ldt) != NULL && 167 pldt1->ldt_refcnt > 1) { 168 pldt = user_ldt_alloc(mdp1, pldt1->ldt_len); 169 if (pldt == NULL) 170 panic("could not copy LDT"); 171 mdp1->md_ldt = pldt; 172 set_user_ldt(mdp1); 173 user_ldt_deref(pldt1); 174 } else 175 mtx_unlock_spin(&dt_lock); 176 } 177 return; 178 } 179 180 /* Ensure that td1's pcb is up to date. */ 181 if (td1 == curthread) 182 td1->td_pcb->pcb_gs = rgs(); 183#ifdef DEV_NPX 184 critical_enter(); 185 if (PCPU_GET(fpcurthread) == td1) 186 npxsave(td1->td_pcb->pcb_save); 187 critical_exit(); 188#endif 189 190 /* Point the pcb to the top of the stack */ 191 pcb2 = (struct pcb *)(td2->td_kstack + 192 td2->td_kstack_pages * PAGE_SIZE) - 1; 193 td2->td_pcb = pcb2; 194 195 /* Copy td1's pcb */ 196 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 197 198 /* Properly initialize pcb_save */ 199 pcb2->pcb_save = &pcb2->pcb_user_save; 200 201 /* Point mdproc and then copy over td1's contents */ 202 mdp2 = &p2->p_md; 203 bcopy(&p1->p_md, mdp2, sizeof(*mdp2)); 204 205 /* 206 * Create a new fresh stack for the new process. 207 * Copy the trap frame for the return to user mode as if from a 208 * syscall. This copies most of the user mode register values. 209 * The -16 is so we can expand the trapframe if we go to vm86. 210 */ 211 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1; 212 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe)); 213 214 td2->td_frame->tf_eax = 0; /* Child returns zero */ 215 td2->td_frame->tf_eflags &= ~PSL_C; /* success */ 216 td2->td_frame->tf_edx = 1; 217 218 /* 219 * If the parent process has the trap bit set (i.e. a debugger had 220 * single stepped the process to the system call), we need to clear 221 * the trap flag from the new frame unless the debugger had set PF_FORK 222 * on the parent. Otherwise, the child will receive a (likely 223 * unexpected) SIGTRAP when it executes the first instruction after 224 * returning to userland. 225 */ 226 if ((p1->p_pfsflags & PF_FORK) == 0) 227 td2->td_frame->tf_eflags &= ~PSL_T; 228 229 /* 230 * Set registers for trampoline to user mode. Leave space for the 231 * return address on stack. These are the kernel mode register values. 232 */ 233#ifdef PAE 234 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdpt); 235#else 236 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir); 237#endif 238 pcb2->pcb_edi = 0; 239 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */ 240 pcb2->pcb_ebp = 0; 241 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *); 242 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */ 243 pcb2->pcb_eip = (int)fork_trampoline; 244 pcb2->pcb_psl = PSL_KERNEL; /* ints disabled */ 245 /*- 246 * pcb2->pcb_dr*: cloned above. 247 * pcb2->pcb_savefpu: cloned above. 248 * pcb2->pcb_flags: cloned above. 249 * pcb2->pcb_onfault: cloned above (always NULL here?). 250 * pcb2->pcb_gs: cloned above. 251 * pcb2->pcb_ext: cleared below. 252 */ 253 254 /* 255 * XXX don't copy the i/o pages. this should probably be fixed. 256 */ 257 pcb2->pcb_ext = 0; 258 259 /* Copy the LDT, if necessary. */ 260 mtx_lock_spin(&dt_lock); 261 if (mdp2->md_ldt != NULL) { 262 if (flags & RFMEM) { 263 mdp2->md_ldt->ldt_refcnt++; 264 } else { 265 mdp2->md_ldt = user_ldt_alloc(mdp2, 266 mdp2->md_ldt->ldt_len); 267 if (mdp2->md_ldt == NULL) 268 panic("could not copy LDT"); 269 } 270 } 271 mtx_unlock_spin(&dt_lock); 272 273 /* Setup to release spin count in fork_exit(). */ 274 td2->td_md.md_spinlock_count = 1; 275 /* 276 * XXX XEN need to check on PSL_USER is handled 277 */ 278 td2->td_md.md_saved_flags = PSL_KERNEL | PSL_I; 279 /* 280 * Now, cpu_switch() can schedule the new process. 281 * pcb_esp is loaded pointing to the cpu_switch() stack frame 282 * containing the return address when exiting cpu_switch. 283 * This will normally be to fork_trampoline(), which will have 284 * %ebx loaded with the new proc's pointer. fork_trampoline() 285 * will set up a stack to call fork_return(p, frame); to complete 286 * the return to user-mode. 287 */ 288} 289 290/* 291 * Intercept the return address from a freshly forked process that has NOT 292 * been scheduled yet. 293 * 294 * This is needed to make kernel threads stay in kernel mode. 295 */ 296void 297cpu_set_fork_handler(td, func, arg) 298 struct thread *td; 299 void (*func)(void *); 300 void *arg; 301{ 302 /* 303 * Note that the trap frame follows the args, so the function 304 * is really called like this: func(arg, frame); 305 */ 306 td->td_pcb->pcb_esi = (int) func; /* function */ 307 td->td_pcb->pcb_ebx = (int) arg; /* first arg */ 308} 309 310void 311cpu_exit(struct thread *td) 312{ 313 314 /* 315 * If this process has a custom LDT, release it. Reset pc->pcb_gs 316 * and %gs before we free it in case they refer to an LDT entry. 317 */ 318 mtx_lock_spin(&dt_lock); 319 if (td->td_proc->p_md.md_ldt) { 320 td->td_pcb->pcb_gs = _udatasel; 321 load_gs(_udatasel); 322 user_ldt_free(td); 323 } else 324 mtx_unlock_spin(&dt_lock); 325} 326 327void 328cpu_thread_exit(struct thread *td) 329{ 330 331#ifdef DEV_NPX 332 critical_enter(); 333 if (td == PCPU_GET(fpcurthread)) 334 npxdrop(); 335 critical_exit(); 336#endif 337 338 /* Disable any hardware breakpoints. */ 339 if (td->td_pcb->pcb_flags & PCB_DBREGS) { 340 reset_dbregs(); 341 td->td_pcb->pcb_flags &= ~PCB_DBREGS; 342 } 343} 344 345void 346cpu_thread_clean(struct thread *td) 347{ 348 struct pcb *pcb; 349 350 pcb = td->td_pcb; 351 if (pcb->pcb_ext != NULL) { 352 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */ 353 /* 354 * XXX do we need to move the TSS off the allocated pages 355 * before freeing them? (not done here) 356 */ 357 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext, 358 ctob(IOPAGES + 1)); 359 pcb->pcb_ext = NULL; 360 } 361} 362 363void 364cpu_thread_swapin(struct thread *td) 365{ 366} 367 368void 369cpu_thread_swapout(struct thread *td) 370{ 371} 372 373void 374cpu_thread_alloc(struct thread *td) 375{ 376 377 td->td_pcb = (struct pcb *)(td->td_kstack + 378 td->td_kstack_pages * PAGE_SIZE) - 1; 379 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1; 380 td->td_pcb->pcb_ext = NULL; 381 td->td_pcb->pcb_save = &td->td_pcb->pcb_user_save; 382} 383 384void 385cpu_thread_free(struct thread *td) 386{ 387 388 cpu_thread_clean(td); 389} 390 391void 392cpu_set_syscall_retval(struct thread *td, int error) 393{ 394 395 switch (error) { 396 case 0: 397 td->td_frame->tf_eax = td->td_retval[0]; 398 td->td_frame->tf_edx = td->td_retval[1]; 399 td->td_frame->tf_eflags &= ~PSL_C; 400 break; 401 402 case ERESTART: 403 /* 404 * Reconstruct pc, assuming lcall $X,y is 7 bytes, int 405 * 0x80 is 2 bytes. We saved this in tf_err. 406 */ 407 td->td_frame->tf_eip -= td->td_frame->tf_err; 408 break; 409 410 case EJUSTRETURN: 411 break; 412 413 default: 414 if (td->td_proc->p_sysent->sv_errsize) { 415 if (error >= td->td_proc->p_sysent->sv_errsize) 416 error = -1; /* XXX */ 417 else 418 error = td->td_proc->p_sysent->sv_errtbl[error]; 419 } 420 td->td_frame->tf_eax = error; 421 td->td_frame->tf_eflags |= PSL_C; 422 break; 423 } 424} 425 426/* 427 * Initialize machine state (pcb and trap frame) for a new thread about to 428 * upcall. Put enough state in the new thread's PCB to get it to go back 429 * userret(), where we can intercept it again to set the return (upcall) 430 * Address and stack, along with those from upcals that are from other sources 431 * such as those generated in thread_userret() itself. 432 */ 433void 434cpu_set_upcall(struct thread *td, struct thread *td0) 435{ 436 struct pcb *pcb2; 437 438 /* Point the pcb to the top of the stack. */ 439 pcb2 = td->td_pcb; 440 441 /* 442 * Copy the upcall pcb. This loads kernel regs. 443 * Those not loaded individually below get their default 444 * values here. 445 */ 446 bcopy(td0->td_pcb, pcb2, sizeof(*pcb2)); 447 pcb2->pcb_flags &= ~(PCB_NPXINITDONE | PCB_NPXUSERINITDONE | 448 PCB_KERNNPX); 449 pcb2->pcb_save = &pcb2->pcb_user_save; 450 451 /* 452 * Create a new fresh stack for the new thread. 453 */ 454 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 455 456 /* If the current thread has the trap bit set (i.e. a debugger had 457 * single stepped the process to the system call), we need to clear 458 * the trap flag from the new frame. Otherwise, the new thread will 459 * receive a (likely unexpected) SIGTRAP when it executes the first 460 * instruction after returning to userland. 461 */ 462 td->td_frame->tf_eflags &= ~PSL_T; 463 464 /* 465 * Set registers for trampoline to user mode. Leave space for the 466 * return address on stack. These are the kernel mode register values. 467 */ 468 pcb2->pcb_edi = 0; 469 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */ 470 pcb2->pcb_ebp = 0; 471 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */ 472 pcb2->pcb_ebx = (int)td; /* trampoline arg */ 473 pcb2->pcb_eip = (int)fork_trampoline; 474 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */ 475 pcb2->pcb_gs = rgs(); 476 /* 477 * If we didn't copy the pcb, we'd need to do the following registers: 478 * pcb2->pcb_cr3: cloned above. 479 * pcb2->pcb_dr*: cloned above. 480 * pcb2->pcb_savefpu: cloned above. 481 * pcb2->pcb_flags: cloned above. 482 * pcb2->pcb_onfault: cloned above (always NULL here?). 483 * pcb2->pcb_gs: cloned above. 484 * pcb2->pcb_ext: cleared below. 485 */ 486 pcb2->pcb_ext = NULL; 487 488 /* Setup to release spin count in fork_exit(). */ 489 td->td_md.md_spinlock_count = 1; 490 td->td_md.md_saved_flags = PSL_KERNEL | PSL_I; 491} 492 493/* 494 * Set that machine state for performing an upcall that has to 495 * be done in thread_userret() so that those upcalls generated 496 * in thread_userret() itself can be done as well. 497 */ 498void 499cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg, 500 stack_t *stack) 501{ 502 503 /* 504 * Do any extra cleaning that needs to be done. 505 * The thread may have optional components 506 * that are not present in a fresh thread. 507 * This may be a recycled thread so make it look 508 * as though it's newly allocated. 509 */ 510 cpu_thread_clean(td); 511 512 /* 513 * Set the trap frame to point at the beginning of the uts 514 * function. 515 */ 516 td->td_frame->tf_ebp = 0; 517 td->td_frame->tf_esp = 518 (((int)stack->ss_sp + stack->ss_size - 4) & ~0x0f) - 4; 519 td->td_frame->tf_eip = (int)entry; 520 521 /* 522 * Pass the address of the mailbox for this kse to the uts 523 * function as a parameter on the stack. 524 */ 525 suword((void *)(td->td_frame->tf_esp + sizeof(void *)), 526 (int)arg); 527} 528 529int 530cpu_set_user_tls(struct thread *td, void *tls_base) 531{ 532 struct segment_descriptor sd; 533 uint32_t base; 534 535 /* 536 * Construct a descriptor and store it in the pcb for 537 * the next context switch. Also store it in the gdt 538 * so that the load of tf_fs into %fs will activate it 539 * at return to userland. 540 */ 541 base = (uint32_t)tls_base; 542 sd.sd_lobase = base & 0xffffff; 543 sd.sd_hibase = (base >> 24) & 0xff; 544 sd.sd_lolimit = 0xffff; /* 4GB limit, wraps around */ 545 sd.sd_hilimit = 0xf; 546 sd.sd_type = SDT_MEMRWA; 547 sd.sd_dpl = SEL_UPL; 548 sd.sd_p = 1; 549 sd.sd_xx = 0; 550 sd.sd_def32 = 1; 551 sd.sd_gran = 1; 552 critical_enter(); 553 /* set %gs */ 554 td->td_pcb->pcb_gsd = sd; 555 if (td == curthread) { 556 PCPU_GET(fsgs_gdt)[1] = sd; 557 load_gs(GSEL(GUGS_SEL, SEL_UPL)); 558 } 559 critical_exit(); 560 return (0); 561} 562 563/* 564 * Convert kernel VA to physical address 565 */ 566vm_paddr_t 567kvtop(void *addr) 568{ 569 vm_paddr_t pa; 570 571 pa = pmap_kextract((vm_offset_t)addr); 572 if (pa == 0) 573 panic("kvtop: zero page frame"); 574 return (pa); 575} 576 577#ifdef SMP 578static void 579cpu_reset_proxy() 580{ 581 cpuset_t tcrp; 582 583 cpu_reset_proxy_active = 1; 584 while (cpu_reset_proxy_active == 1) 585 ; /* Wait for other cpu to see that we've started */ 586 CPU_SETOF(cpu_reset_proxyid, &tcrp); 587 stop_cpus(tcrp); 588 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid); 589 DELAY(1000000); 590 cpu_reset_real(); 591} 592#endif 593 594void 595cpu_reset() 596{ 597#ifdef XBOX 598 if (arch_i386_is_xbox) { 599 /* Kick the PIC16L, it can reboot the box */ 600 pic16l_reboot(); 601 for (;;); 602 } 603#endif 604 605#ifdef SMP 606 cpuset_t map; 607 u_int cnt; 608 609 if (smp_active) { 610 map = all_cpus; 611 CPU_CLR(PCPU_GET(cpuid), &map); 612 CPU_NAND(&map, &stopped_cpus); 613 if (!CPU_EMPTY(&map)) { 614 printf("cpu_reset: Stopping other CPUs\n"); 615 stop_cpus(map); 616 } 617 618 if (PCPU_GET(cpuid) != 0) { 619 cpu_reset_proxyid = PCPU_GET(cpuid); 620 cpustop_restartfunc = cpu_reset_proxy; 621 cpu_reset_proxy_active = 0; 622 printf("cpu_reset: Restarting BSP\n"); 623 624 /* Restart CPU #0. */ 625 /* XXX: restart_cpus(1 << 0); */ 626 CPU_SETOF(0, &started_cpus); 627 wmb(); 628 629 cnt = 0; 630 while (cpu_reset_proxy_active == 0 && cnt < 10000000) 631 cnt++; /* Wait for BSP to announce restart */ 632 if (cpu_reset_proxy_active == 0) 633 printf("cpu_reset: Failed to restart BSP\n"); 634 enable_intr(); 635 cpu_reset_proxy_active = 2; 636 637 while (1); 638 /* NOTREACHED */ 639 } 640 641 DELAY(1000000); 642 } 643#endif 644 cpu_reset_real(); 645 /* NOTREACHED */ 646} 647 648static void 649cpu_reset_real() 650{ 651 struct region_descriptor null_idt; 652#ifndef PC98 653 int b; 654#endif 655 656 disable_intr(); 657#ifdef XEN 658 if (smp_processor_id() == 0) 659 HYPERVISOR_shutdown(SHUTDOWN_reboot); 660 else 661 HYPERVISOR_shutdown(SHUTDOWN_poweroff); 662#endif 663#ifdef CPU_ELAN 664 if (elan_mmcr != NULL) 665 elan_mmcr->RESCFG = 1; 666#endif 667 668 if (cpu == CPU_GEODE1100) { 669 /* Attempt Geode's own reset */ 670 outl(0xcf8, 0x80009044ul); 671 outl(0xcfc, 0xf); 672 } 673 674#ifdef PC98 675 /* 676 * Attempt to do a CPU reset via CPU reset port. 677 */ 678 if ((inb(0x35) & 0xa0) != 0xa0) { 679 outb(0x37, 0x0f); /* SHUT0 = 0. */ 680 outb(0x37, 0x0b); /* SHUT1 = 0. */ 681 } 682 outb(0xf0, 0x00); /* Reset. */ 683#else 684#if !defined(BROKEN_KEYBOARD_RESET) 685 /* 686 * Attempt to do a CPU reset via the keyboard controller, 687 * do not turn off GateA20, as any machine that fails 688 * to do the reset here would then end up in no man's land. 689 */ 690 outb(IO_KBD + 4, 0xFE); 691 DELAY(500000); /* wait 0.5 sec to see if that did it */ 692#endif 693 694 /* 695 * Attempt to force a reset via the Reset Control register at 696 * I/O port 0xcf9. Bit 2 forces a system reset when it 697 * transitions from 0 to 1. Bit 1 selects the type of reset 698 * to attempt: 0 selects a "soft" reset, and 1 selects a 699 * "hard" reset. We try a "hard" reset. The first write sets 700 * bit 1 to select a "hard" reset and clears bit 2. The 701 * second write forces a 0 -> 1 transition in bit 2 to trigger 702 * a reset. 703 */ 704 outb(0xcf9, 0x2); 705 outb(0xcf9, 0x6); 706 DELAY(500000); /* wait 0.5 sec to see if that did it */ 707 708 /* 709 * Attempt to force a reset via the Fast A20 and Init register 710 * at I/O port 0x92. Bit 1 serves as an alternate A20 gate. 711 * Bit 0 asserts INIT# when set to 1. We are careful to only 712 * preserve bit 1 while setting bit 0. We also must clear bit 713 * 0 before setting it if it isn't already clear. 714 */ 715 b = inb(0x92); 716 if (b != 0xff) { 717 if ((b & 0x1) != 0) 718 outb(0x92, b & 0xfe); 719 outb(0x92, b | 0x1); 720 DELAY(500000); /* wait 0.5 sec to see if that did it */ 721 } 722#endif /* PC98 */ 723 724 printf("No known reset method worked, attempting CPU shutdown\n"); 725 DELAY(1000000); /* wait 1 sec for printf to complete */ 726 727 /* Wipe the IDT. */ 728 null_idt.rd_limit = 0; 729 null_idt.rd_base = 0; 730 lidt(&null_idt); 731 732 /* "good night, sweet prince .... <THUNK!>" */ 733 breakpoint(); 734 735 /* NOTREACHED */ 736 while(1); 737} 738 739/* 740 * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-)) 741 */ 742static void 743sf_buf_init(void *arg) 744{ 745 struct sf_buf *sf_bufs; 746 vm_offset_t sf_base; 747 int i; 748 749 nsfbufs = NSFBUFS; 750 TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs); 751 752 sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask); 753 TAILQ_INIT(&sf_buf_freelist); 754 sf_base = kmem_alloc_nofault(kernel_map, nsfbufs * PAGE_SIZE); 755 sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP, 756 M_NOWAIT | M_ZERO); 757 for (i = 0; i < nsfbufs; i++) { 758 sf_bufs[i].kva = sf_base + i * PAGE_SIZE; 759 TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry); 760 } 761 sf_buf_alloc_want = 0; 762 mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF); 763} 764 765/* 766 * Invalidate the cache lines that may belong to the page, if 767 * (possibly old) mapping of the page by sf buffer exists. Returns 768 * TRUE when mapping was found and cache invalidated. 769 */ 770boolean_t 771sf_buf_invalidate_cache(vm_page_t m) 772{ 773 struct sf_head *hash_list; 774 struct sf_buf *sf; 775 boolean_t ret; 776 777 hash_list = &sf_buf_active[SF_BUF_HASH(m)]; 778 ret = FALSE; 779 mtx_lock(&sf_buf_lock); 780 LIST_FOREACH(sf, hash_list, list_entry) { 781 if (sf->m == m) { 782 /* 783 * Use pmap_qenter to update the pte for 784 * existing mapping, in particular, the PAT 785 * settings are recalculated. 786 */ 787 pmap_qenter(sf->kva, &m, 1); 788 pmap_invalidate_cache_range(sf->kva, sf->kva + 789 PAGE_SIZE); 790 ret = TRUE; 791 break; 792 } 793 } 794 mtx_unlock(&sf_buf_lock); 795 return (ret); 796} 797 798/* 799 * Get an sf_buf from the freelist. May block if none are available. 800 */ 801struct sf_buf * 802sf_buf_alloc(struct vm_page *m, int flags) 803{ 804 pt_entry_t opte, *ptep; 805 struct sf_head *hash_list; 806 struct sf_buf *sf; 807#ifdef SMP 808 cpuset_t other_cpus; 809 u_int cpuid; 810#endif 811 int error; 812 813 KASSERT(curthread->td_pinned > 0 || (flags & SFB_CPUPRIVATE) == 0, 814 ("sf_buf_alloc(SFB_CPUPRIVATE): curthread not pinned")); 815 hash_list = &sf_buf_active[SF_BUF_HASH(m)]; 816 mtx_lock(&sf_buf_lock); 817 LIST_FOREACH(sf, hash_list, list_entry) { 818 if (sf->m == m) { 819 sf->ref_count++; 820 if (sf->ref_count == 1) { 821 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 822 nsfbufsused++; 823 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 824 } 825#ifdef SMP 826 goto shootdown; 827#else 828 goto done; 829#endif 830 } 831 } 832 while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) { 833 if (flags & SFB_NOWAIT) 834 goto done; 835 sf_buf_alloc_want++; 836 mbstat.sf_allocwait++; 837 error = msleep(&sf_buf_freelist, &sf_buf_lock, 838 (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0); 839 sf_buf_alloc_want--; 840 841 /* 842 * If we got a signal, don't risk going back to sleep. 843 */ 844 if (error) 845 goto done; 846 } 847 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 848 if (sf->m != NULL) 849 LIST_REMOVE(sf, list_entry); 850 LIST_INSERT_HEAD(hash_list, sf, list_entry); 851 sf->ref_count = 1; 852 sf->m = m; 853 nsfbufsused++; 854 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 855 856 /* 857 * Update the sf_buf's virtual-to-physical mapping, flushing the 858 * virtual address from the TLB. Since the reference count for 859 * the sf_buf's old mapping was zero, that mapping is not 860 * currently in use. Consequently, there is no need to exchange 861 * the old and new PTEs atomically, even under PAE. 862 */ 863 ptep = vtopte(sf->kva); 864 opte = *ptep; 865#ifdef XEN 866 PT_SET_MA(sf->kva, xpmap_ptom(VM_PAGE_TO_PHYS(m)) | pgeflag 867 | PG_RW | PG_V | pmap_cache_bits(m->md.pat_mode, 0)); 868#else 869 *ptep = VM_PAGE_TO_PHYS(m) | pgeflag | PG_RW | PG_V | 870 pmap_cache_bits(m->md.pat_mode, 0); 871#endif 872 873 /* 874 * Avoid unnecessary TLB invalidations: If the sf_buf's old 875 * virtual-to-physical mapping was not used, then any processor 876 * that has invalidated the sf_buf's virtual address from its TLB 877 * since the last used mapping need not invalidate again. 878 */ 879#ifdef SMP 880 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A)) 881 CPU_ZERO(&sf->cpumask); 882shootdown: 883 sched_pin(); 884 cpuid = PCPU_GET(cpuid); 885 if (!CPU_ISSET(cpuid, &sf->cpumask)) { 886 CPU_SET(cpuid, &sf->cpumask); 887 invlpg(sf->kva); 888 } 889 if ((flags & SFB_CPUPRIVATE) == 0) { 890 other_cpus = all_cpus; 891 CPU_CLR(cpuid, &other_cpus); 892 CPU_NAND(&other_cpus, &sf->cpumask); 893 if (!CPU_EMPTY(&other_cpus)) { 894 CPU_OR(&sf->cpumask, &other_cpus); 895 smp_masked_invlpg(other_cpus, sf->kva); 896 } 897 } 898 sched_unpin(); 899#else 900 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A)) 901 pmap_invalidate_page(kernel_pmap, sf->kva); 902#endif 903done: 904 mtx_unlock(&sf_buf_lock); 905 return (sf); 906} 907 908/* 909 * Remove a reference from the given sf_buf, adding it to the free 910 * list when its reference count reaches zero. A freed sf_buf still, 911 * however, retains its virtual-to-physical mapping until it is 912 * recycled or reactivated by sf_buf_alloc(9). 913 */ 914void 915sf_buf_free(struct sf_buf *sf) 916{ 917 918 mtx_lock(&sf_buf_lock); 919 sf->ref_count--; 920 if (sf->ref_count == 0) { 921 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry); 922 nsfbufsused--; 923#ifdef XEN 924/* 925 * Xen doesn't like having dangling R/W mappings 926 */ 927 pmap_qremove(sf->kva, 1); 928 sf->m = NULL; 929 LIST_REMOVE(sf, list_entry); 930#endif 931 if (sf_buf_alloc_want > 0) 932 wakeup(&sf_buf_freelist); 933 } 934 mtx_unlock(&sf_buf_lock); 935} 936 937/* 938 * Software interrupt handler for queued VM system processing. 939 */ 940void 941swi_vm(void *dummy) 942{ 943 if (busdma_swi_pending != 0) 944 busdma_swi(); 945} 946 947/* 948 * Tell whether this address is in some physical memory region. 949 * Currently used by the kernel coredump code in order to avoid 950 * dumping the ``ISA memory hole'' which could cause indefinite hangs, 951 * or other unpredictable behaviour. 952 */ 953 954int 955is_physical_memory(vm_paddr_t addr) 956{ 957 958#ifdef DEV_ISA 959 /* The ISA ``memory hole''. */ 960 if (addr >= 0xa0000 && addr < 0x100000) 961 return 0; 962#endif 963 964 /* 965 * stuff other tests for known memory-mapped devices (PCI?) 966 * here 967 */ 968 969 return 1; 970} 971