1 /*- 2 * Copyright (c) 1982, 1986 The Regents of the University of California. 3 * Copyright (c) 1989, 1990 William Jolitz 4 * Copyright (c) 1994 John Dyson 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department, and William Jolitz. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91 40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ 41 * $FreeBSD$ 42 */ 43 44 #include "opt_npx.h" 45 #ifdef PC98 46 #include "opt_pc98.h" 47 #endif 48 #include "opt_reset.h" 49 #include "opt_isa.h" 50 #include "opt_kstack_pages.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/malloc.h> 55 #include <sys/proc.h> 56 #include <sys/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 90 static void cpu_reset_real(void); 91 #ifdef SMP 92 static void cpu_reset_proxy(void); 93 static u_int cpu_reset_proxyid; 94 static volatile u_int cpu_reset_proxy_active; 95 #endif 96 extern int _ucodesel, _udatasel; 97 98 /* 99 * Finish a fork operation, with process p2 nearly set up. 100 * Copy and update the pcb, set up the stack so that the child 101 * ready to run and return to user mode. 102 */ 103 void 104 cpu_fork(td1, p2, td2, flags) 105 register struct thread *td1; 106 register struct proc *p2; 107 struct thread *td2; 108 int flags; 109 { 110 register struct proc *p1; 111 struct pcb *pcb2; 112 struct mdproc *mdp2; 113 #ifdef DEV_NPX 114 register_t savecrit; 115 #endif 116 117 p1 = td1->td_proc; 118 if ((flags & RFPROC) == 0) { 119 if ((flags & RFMEM) == 0) { 120 /* unshare user LDT */ 121 struct mdproc *mdp1 = &p1->p_md; 122 struct proc_ldt *pldt = mdp1->md_ldt; 123 if (pldt && pldt->ldt_refcnt > 1) { 124 pldt = user_ldt_alloc(mdp1, pldt->ldt_len); 125 if (pldt == NULL) 126 panic("could not copy LDT"); 127 mdp1->md_ldt = pldt; 128 set_user_ldt(mdp1); 129 user_ldt_free(td1); 130 } 131 } 132 return; 133 } 134 135 /* Ensure that p1's pcb is up to date. */ 136 #ifdef DEV_NPX 137 if (td1 == curthread) 138 td1->td_pcb->pcb_gs = rgs(); 139 savecrit = intr_disable(); 140 if (PCPU_GET(fpcurthread) == td1) 141 npxsave(&td1->td_pcb->pcb_save); 142 intr_restore(savecrit); 143 #endif 144 145 /* Point the pcb to the top of the stack */ 146 pcb2 = (struct pcb *)(td2->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1; 147 td2->td_pcb = pcb2; 148 149 /* Copy p1's pcb */ 150 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 151 152 /* Point mdproc and then copy over td1's contents */ 153 mdp2 = &p2->p_md; 154 bcopy(&p1->p_md, mdp2, sizeof(*mdp2)); 155 156 /* 157 * Create a new fresh stack for the new process. 158 * Copy the trap frame for the return to user mode as if from a 159 * syscall. This copies most of the user mode register values. 160 * The -16 is so we can expand the trapframe if we go to vm86. 161 */ 162 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1; 163 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe)); 164 165 td2->td_frame->tf_eax = 0; /* Child returns zero */ 166 td2->td_frame->tf_eflags &= ~PSL_C; /* success */ 167 td2->td_frame->tf_edx = 1; 168 169 /* 170 * Set registers for trampoline to user mode. Leave space for the 171 * return address on stack. These are the kernel mode register values. 172 */ 173 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir); 174 pcb2->pcb_edi = 0; 175 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */ 176 pcb2->pcb_ebp = 0; 177 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *); 178 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */ 179 pcb2->pcb_eip = (int)fork_trampoline; 180 pcb2->pcb_psl = td2->td_frame->tf_eflags & ~PSL_I; /* ints disabled */ 181 /*- 182 * pcb2->pcb_dr*: cloned above. 183 * pcb2->pcb_savefpu: cloned above. 184 * pcb2->pcb_flags: cloned above. 185 * pcb2->pcb_onfault: cloned above (always NULL here?). 186 * pcb2->pcb_gs: cloned above. 187 * pcb2->pcb_ext: cleared below. 188 */ 189 190 /* 191 * XXX don't copy the i/o pages. this should probably be fixed. 192 */ 193 pcb2->pcb_ext = 0; 194 195 /* Copy the LDT, if necessary. */ 196 mtx_lock_spin(&sched_lock); 197 if (mdp2->md_ldt != 0) { 198 if (flags & RFMEM) { 199 mdp2->md_ldt->ldt_refcnt++; 200 } else { 201 mdp2->md_ldt = user_ldt_alloc(mdp2, 202 mdp2->md_ldt->ldt_len); 203 if (mdp2->md_ldt == NULL) 204 panic("could not copy LDT"); 205 } 206 } 207 mtx_unlock_spin(&sched_lock); 208 209 /* 210 * Now, cpu_switch() can schedule the new process. 211 * pcb_esp is loaded pointing to the cpu_switch() stack frame 212 * containing the return address when exiting cpu_switch. 213 * This will normally be to fork_trampoline(), which will have 214 * %ebx loaded with the new proc's pointer. fork_trampoline() 215 * will set up a stack to call fork_return(p, frame); to complete 216 * the return to user-mode. 217 */ 218 } 219 220 /* 221 * Intercept the return address from a freshly forked process that has NOT 222 * been scheduled yet. 223 * 224 * This is needed to make kernel threads stay in kernel mode. 225 */ 226 void 227 cpu_set_fork_handler(td, func, arg) 228 struct thread *td; 229 void (*func)(void *); 230 void *arg; 231 { 232 /* 233 * Note that the trap frame follows the args, so the function 234 * is really called like this: func(arg, frame); 235 */ 236 td->td_pcb->pcb_esi = (int) func; /* function */ 237 td->td_pcb->pcb_ebx = (int) arg; /* first arg */ 238 } 239 240 void 241 cpu_exit(struct thread *td) 242 { 243 struct mdproc *mdp; 244 245 mdp = &td->td_proc->p_md; 246 if (mdp->md_ldt) 247 user_ldt_free(td); 248 reset_dbregs(); 249 } 250 251 void 252 cpu_thread_exit(struct thread *td) 253 { 254 struct pcb *pcb = td->td_pcb; 255 #ifdef DEV_NPX 256 npxexit(td); 257 #endif 258 if (pcb->pcb_flags & PCB_DBREGS) { 259 /* 260 * disable all hardware breakpoints 261 */ 262 reset_dbregs(); 263 pcb->pcb_flags &= ~PCB_DBREGS; 264 } 265 } 266 267 void 268 cpu_thread_clean(struct thread *td) 269 { 270 struct pcb *pcb; 271 272 pcb = td->td_pcb; 273 if (pcb->pcb_ext != 0) { 274 /* XXXKSE XXXSMP not SMP SAFE.. what locks do we have? */ 275 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */ 276 /* 277 * XXX do we need to move the TSS off the allocated pages 278 * before freeing them? (not done here) 279 */ 280 mtx_lock(&Giant); 281 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext, 282 ctob(IOPAGES + 1)); 283 mtx_unlock(&Giant); 284 pcb->pcb_ext = 0; 285 } 286 } 287 288 void 289 cpu_sched_exit(td) 290 register struct thread *td; 291 { 292 } 293 294 void 295 cpu_thread_setup(struct thread *td) 296 { 297 298 td->td_pcb = 299 (struct pcb *)(td->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1; 300 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1; 301 } 302 303 /* 304 * Initialize machine state (pcb and trap frame) for a new thread about to 305 * upcall. Pu t enough state in the new thread's PCB to get it to go back 306 * userret(), where we can intercept it again to set the return (upcall) 307 * Address and stack, along with those from upcals that are from other sources 308 * such as those generated in thread_userret() itself. 309 */ 310 void 311 cpu_set_upcall(struct thread *td, void *pcb) 312 { 313 struct pcb *pcb2; 314 315 /* Point the pcb to the top of the stack. */ 316 pcb2 = td->td_pcb; 317 318 /* 319 * Copy the upcall pcb. This loads kernel regs. 320 * Those not loaded individually below get their default 321 * values here. 322 * 323 * XXXKSE It might be a good idea to simply skip this as 324 * the values of the other registers may be unimportant. 325 * This would remove any requirement for knowing the KSE 326 * at this time (see the matching comment below for 327 * more analysis) (need a good safe default). 328 */ 329 bcopy(pcb, pcb2, sizeof(*pcb2)); 330 331 /* 332 * Create a new fresh stack for the new thread. 333 * The -16 is so we can expand the trapframe if we go to vm86. 334 * Don't forget to set this stack value into whatever supplies 335 * the address for the fault handlers. 336 * The contexts are filled in at the time we actually DO the 337 * upcall as only then do we know which KSE we got. 338 */ 339 td->td_frame = (struct trapframe *)((caddr_t)pcb2 - 16) - 1; 340 341 /* 342 * Set registers for trampoline to user mode. Leave space for the 343 * return address on stack. These are the kernel mode register values. 344 */ 345 pcb2->pcb_cr3 = vtophys(vmspace_pmap(td->td_proc->p_vmspace)->pm_pdir); 346 pcb2->pcb_edi = 0; 347 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */ 348 pcb2->pcb_ebp = 0; 349 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */ 350 pcb2->pcb_ebx = (int)td; /* trampoline arg */ 351 pcb2->pcb_eip = (int)fork_trampoline; 352 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */ 353 /* 354 * If we didn't copy the pcb, we'd need to do the following registers: 355 * pcb2->pcb_dr*: cloned above. 356 * pcb2->pcb_savefpu: cloned above. 357 * pcb2->pcb_flags: cloned above. 358 * pcb2->pcb_onfault: cloned above (always NULL here?). 359 * pcb2->pcb_gs: cloned above. XXXKSE ??? 360 * pcb2->pcb_ext: cleared below. 361 */ 362 pcb2->pcb_ext = NULL; 363 } 364 365 /* 366 * Set that machine state for performing an upcall that has to 367 * be done in thread_userret() so that those upcalls generated 368 * in thread_userret() itself can be done as well. 369 */ 370 void 371 cpu_set_upcall_kse(struct thread *td, struct kse_upcall *ku) 372 { 373 374 /* 375 * Do any extra cleaning that needs to be done. 376 * The thread may have optional components 377 * that are not present in a fresh thread. 378 * This may be a recycled thread so make it look 379 * as though it's newly allocated. 380 */ 381 cpu_thread_clean(td); 382 383 /* 384 * Set the trap frame to point at the beginning of the uts 385 * function. 386 */ 387 td->td_frame->tf_esp = 388 (int)ku->ku_stack.ss_sp + ku->ku_stack.ss_size - 16; 389 td->td_frame->tf_eip = (int)ku->ku_func; 390 391 /* 392 * Pass the address of the mailbox for this kse to the uts 393 * function as a parameter on the stack. 394 */ 395 suword((void *)(td->td_frame->tf_esp + sizeof(void *)), 396 (int)ku->ku_mailbox); 397 } 398 399 void 400 cpu_wait(p) 401 struct proc *p; 402 { 403 } 404 405 /* 406 * Convert kernel VA to physical address 407 */ 408 vm_paddr_t 409 kvtop(void *addr) 410 { 411 vm_paddr_t pa; 412 413 pa = pmap_kextract((vm_offset_t)addr); 414 if (pa == 0) 415 panic("kvtop: zero page frame"); 416 return (pa); 417 } 418 419 /* 420 * Force reset the processor by invalidating the entire address space! 421 */ 422 423 #ifdef SMP 424 static void 425 cpu_reset_proxy() 426 { 427 428 cpu_reset_proxy_active = 1; 429 while (cpu_reset_proxy_active == 1) 430 ; /* Wait for other cpu to see that we've started */ 431 stop_cpus((1<<cpu_reset_proxyid)); 432 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid); 433 DELAY(1000000); 434 cpu_reset_real(); 435 } 436 #endif 437 438 void 439 cpu_reset() 440 { 441 #ifdef SMP 442 if (smp_active == 0) { 443 cpu_reset_real(); 444 /* NOTREACHED */ 445 } else { 446 447 u_int map; 448 int cnt; 449 printf("cpu_reset called on cpu#%d\n", PCPU_GET(cpuid)); 450 451 map = PCPU_GET(other_cpus) & ~ stopped_cpus; 452 453 if (map != 0) { 454 printf("cpu_reset: Stopping other CPUs\n"); 455 stop_cpus(map); /* Stop all other CPUs */ 456 } 457 458 if (PCPU_GET(cpuid) == 0) { 459 DELAY(1000000); 460 cpu_reset_real(); 461 /* NOTREACHED */ 462 } else { 463 /* We are not BSP (CPU #0) */ 464 465 cpu_reset_proxyid = PCPU_GET(cpuid); 466 cpustop_restartfunc = cpu_reset_proxy; 467 cpu_reset_proxy_active = 0; 468 printf("cpu_reset: Restarting BSP\n"); 469 started_cpus = (1<<0); /* Restart CPU #0 */ 470 471 cnt = 0; 472 while (cpu_reset_proxy_active == 0 && cnt < 10000000) 473 cnt++; /* Wait for BSP to announce restart */ 474 if (cpu_reset_proxy_active == 0) 475 printf("cpu_reset: Failed to restart BSP\n"); 476 enable_intr(); 477 cpu_reset_proxy_active = 2; 478 479 while (1); 480 /* NOTREACHED */ 481 } 482 } 483 #else 484 cpu_reset_real(); 485 #endif 486 } 487 488 static void 489 cpu_reset_real() 490 { 491 492 #ifdef PC98 493 /* 494 * Attempt to do a CPU reset via CPU reset port. 495 */ 496 disable_intr(); 497 if ((inb(0x35) & 0xa0) != 0xa0) { 498 outb(0x37, 0x0f); /* SHUT0 = 0. */ 499 outb(0x37, 0x0b); /* SHUT1 = 0. */ 500 } 501 outb(0xf0, 0x00); /* Reset. */ 502 #else 503 /* 504 * Attempt to do a CPU reset via the keyboard controller, 505 * do not turn of the GateA20, as any machine that fails 506 * to do the reset here would then end up in no man's land. 507 */ 508 509 #if !defined(BROKEN_KEYBOARD_RESET) 510 outb(IO_KBD + 4, 0xFE); 511 DELAY(500000); /* wait 0.5 sec to see if that did it */ 512 printf("Keyboard reset did not work, attempting CPU shutdown\n"); 513 DELAY(1000000); /* wait 1 sec for printf to complete */ 514 #endif 515 #endif /* PC98 */ 516 /* force a shutdown by unmapping entire address space ! */ 517 bzero((caddr_t)PTD, NBPTD); 518 519 /* "good night, sweet prince .... <THUNK!>" */ 520 invltlb(); 521 /* NOTREACHED */ 522 while(1); 523 } 524 525 /* 526 * Software interrupt handler for queued VM system processing. 527 */ 528 void 529 swi_vm(void *dummy) 530 { 531 if (busdma_swi_pending != 0) 532 busdma_swi(); 533 } 534 535 /* 536 * Tell whether this address is in some physical memory region. 537 * Currently used by the kernel coredump code in order to avoid 538 * dumping the ``ISA memory hole'' which could cause indefinite hangs, 539 * or other unpredictable behaviour. 540 */ 541 542 int 543 is_physical_memory(addr) 544 vm_offset_t addr; 545 { 546 547 #ifdef DEV_ISA 548 /* The ISA ``memory hole''. */ 549 if (addr >= 0xa0000 && addr < 0x100000) 550 return 0; 551 #endif 552 553 /* 554 * stuff other tests for known memory-mapped devices (PCI?) 555 * here 556 */ 557 558 return 1; 559 } 560