1 /* $NetBSD: linux_machdep.c,v 1.29 1996/05/03 19:42:11 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Frank van der Linden 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed for the NetBSD Project 18 * by Frank van der Linden 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/signalvar.h> 37 #include <sys/kernel.h> 38 #include <sys/map.h> 39 #include <sys/proc.h> 40 #include <sys/user.h> 41 #include <sys/buf.h> 42 #include <sys/reboot.h> 43 #include <sys/conf.h> 44 #include <sys/file.h> 45 #include <sys/callout.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/msgbuf.h> 49 #include <sys/mount.h> 50 #include <sys/vnode.h> 51 #include <sys/device.h> 52 #include <sys/sysctl.h> 53 #include <sys/syscallargs.h> 54 #include <sys/filedesc.h> 55 56 #include <compat/linux/linux_types.h> 57 #include <compat/linux/linux_signal.h> 58 #include <compat/linux/linux_syscallargs.h> 59 #include <compat/linux/linux_util.h> 60 #include <compat/linux/linux_ioctl.h> 61 62 #include <machine/cpu.h> 63 #include <machine/cpufunc.h> 64 #include <machine/psl.h> 65 #include <machine/reg.h> 66 #include <machine/segments.h> 67 #include <machine/specialreg.h> 68 #include <machine/sysarch.h> 69 #include <machine/vm86.h> 70 #include <machine/linux_machdep.h> 71 72 /* 73 * To see whether pcvt is configured (for virtual console ioctl calls). 74 */ 75 #include "vt.h" 76 #if NVT > 0 77 #include <arch/i386/isa/pcvt/pcvt_ioctl.h> 78 #endif 79 80 #ifdef USER_LDT 81 #include <machine/cpu.h> 82 int linux_read_ldt __P((struct proc *, struct linux_sys_modify_ldt_args *, 83 register_t *)); 84 int linux_write_ldt __P((struct proc *, struct linux_sys_modify_ldt_args *, 85 register_t *)); 86 #endif 87 88 /* 89 * Deal with some i386-specific things in the Linux emulation code. 90 * This means just signals for now, will include stuff like 91 * I/O map permissions and V86 mode sometime. 92 */ 93 94 /* 95 * Send an interrupt to process. 96 * 97 * Stack is set up to allow sigcode stored 98 * in u. to call routine, followed by kcall 99 * to sigreturn routine below. After sigreturn 100 * resets the signal mask, the stack, and the 101 * frame pointer, it returns to the user 102 * specified pc, psl. 103 */ 104 105 void 106 linux_sendsig(catcher, sig, mask, code) 107 sig_t catcher; 108 int sig, mask; 109 u_long code; 110 { 111 register struct proc *p = curproc; 112 register struct trapframe *tf; 113 struct linux_sigframe *fp, frame; 114 struct sigacts *psp = p->p_sigacts; 115 int oonstack; 116 extern char linux_sigcode[], linux_esigcode[]; 117 118 tf = p->p_md.md_regs; 119 oonstack = psp->ps_sigstk.ss_flags & SS_ONSTACK; 120 121 /* 122 * Allocate space for the signal handler context. 123 */ 124 if ((psp->ps_flags & SAS_ALTSTACK) && !oonstack && 125 (psp->ps_sigonstack & sigmask(sig))) { 126 fp = (struct linux_sigframe *)(psp->ps_sigstk.ss_sp + 127 psp->ps_sigstk.ss_size - sizeof(struct linux_sigframe)); 128 psp->ps_sigstk.ss_flags |= SS_ONSTACK; 129 } else { 130 fp = (struct linux_sigframe *)tf->tf_esp - 1; 131 } 132 133 frame.sf_handler = catcher; 134 frame.sf_sig = bsd_to_linux_sig[sig]; 135 136 /* 137 * Build the signal context to be used by sigreturn. 138 */ 139 frame.sf_sc.sc_mask = mask; 140 #ifdef VM86 141 if (tf->tf_eflags & PSL_VM) { 142 frame.sf_sc.sc_gs = tf->tf_vm86_gs; 143 frame.sf_sc.sc_fs = tf->tf_vm86_fs; 144 frame.sf_sc.sc_es = tf->tf_vm86_es; 145 frame.sf_sc.sc_ds = tf->tf_vm86_ds; 146 frame.sf_sc.sc_eflags = get_vflags(p); 147 } else 148 #endif 149 { 150 __asm("movl %%gs,%w0" : "=r" (frame.sf_sc.sc_gs)); 151 __asm("movl %%fs,%w0" : "=r" (frame.sf_sc.sc_fs)); 152 frame.sf_sc.sc_es = tf->tf_es; 153 frame.sf_sc.sc_ds = tf->tf_ds; 154 frame.sf_sc.sc_eflags = tf->tf_eflags; 155 } 156 frame.sf_sc.sc_edi = tf->tf_edi; 157 frame.sf_sc.sc_esi = tf->tf_esi; 158 frame.sf_sc.sc_ebp = tf->tf_ebp; 159 frame.sf_sc.sc_ebx = tf->tf_ebx; 160 frame.sf_sc.sc_edx = tf->tf_edx; 161 frame.sf_sc.sc_ecx = tf->tf_ecx; 162 frame.sf_sc.sc_eax = tf->tf_eax; 163 frame.sf_sc.sc_eip = tf->tf_eip; 164 frame.sf_sc.sc_cs = tf->tf_cs; 165 frame.sf_sc.sc_esp_at_signal = tf->tf_esp; 166 frame.sf_sc.sc_ss = tf->tf_ss; 167 frame.sf_sc.sc_err = tf->tf_err; 168 frame.sf_sc.sc_trapno = tf->tf_trapno; 169 170 if (copyout(&frame, fp, sizeof(frame)) != 0) { 171 /* 172 * Process has trashed its stack; give it an illegal 173 * instruction to halt it in its tracks. 174 */ 175 sigexit(p, SIGILL); 176 /* NOTREACHED */ 177 } 178 179 /* 180 * Build context to run handler in. 181 */ 182 tf->tf_es = GSEL(GUDATA_SEL, SEL_UPL); 183 tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL); 184 tf->tf_eip = (int)(((char *)PS_STRINGS) - 185 (linux_esigcode - linux_sigcode)); 186 tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL); 187 tf->tf_eflags &= ~(PSL_T|PSL_VM|PSL_AC); 188 tf->tf_esp = (int)fp; 189 tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL); 190 } 191 192 /* 193 * System call to cleanup state after a signal 194 * has been taken. Reset signal mask and 195 * stack state from context left by sendsig (above). 196 * Return to previous pc and psl as specified by 197 * context left by sendsig. Check carefully to 198 * make sure that the user has not modified the 199 * psl to gain improper privileges or to cause 200 * a machine fault. 201 */ 202 int 203 linux_sys_sigreturn(p, v, retval) 204 struct proc *p; 205 void *v; 206 register_t *retval; 207 { 208 struct linux_sys_sigreturn_args /* { 209 syscallarg(struct linux_sigcontext *) scp; 210 } */ *uap = v; 211 struct linux_sigcontext *scp, context; 212 register struct trapframe *tf; 213 214 tf = p->p_md.md_regs; 215 216 /* 217 * The trampoline code hands us the context. 218 * It is unsafe to keep track of it ourselves, in the event that a 219 * program jumps out of a signal handler. 220 */ 221 scp = SCARG(uap, scp); 222 if (copyin((caddr_t)scp, &context, sizeof(*scp)) != 0) 223 return (EFAULT); 224 225 /* 226 * Restore signal context. 227 */ 228 #ifdef VM86 229 if (context.sc_eflags & PSL_VM) { 230 tf->tf_vm86_gs = context.sc_gs; 231 tf->tf_vm86_fs = context.sc_fs; 232 tf->tf_vm86_es = context.sc_es; 233 tf->tf_vm86_ds = context.sc_ds; 234 set_vflags(p, context.sc_eflags); 235 } else 236 #endif 237 { 238 /* 239 * Check for security violations. If we're returning to 240 * protected mode, the CPU will validate the segment registers 241 * automatically and generate a trap on violations. We handle 242 * the trap, rather than doing all of the checking here. 243 */ 244 if (((context.sc_eflags ^ tf->tf_eflags) & PSL_USERSTATIC) != 0 || 245 !USERMODE(context.sc_cs, context.sc_eflags)) 246 return (EINVAL); 247 248 /* %fs and %gs were restored by the trampoline. */ 249 tf->tf_es = context.sc_es; 250 tf->tf_ds = context.sc_ds; 251 tf->tf_eflags = context.sc_eflags; 252 } 253 tf->tf_edi = context.sc_edi; 254 tf->tf_esi = context.sc_esi; 255 tf->tf_ebp = context.sc_ebp; 256 tf->tf_ebx = context.sc_ebx; 257 tf->tf_edx = context.sc_edx; 258 tf->tf_ecx = context.sc_ecx; 259 tf->tf_eax = context.sc_eax; 260 tf->tf_eip = context.sc_eip; 261 tf->tf_cs = context.sc_cs; 262 tf->tf_esp = context.sc_esp_at_signal; 263 tf->tf_ss = context.sc_ss; 264 265 p->p_sigacts->ps_sigstk.ss_flags &= ~SS_ONSTACK; 266 p->p_sigmask = context.sc_mask & ~sigcantmask; 267 268 return (EJUSTRETURN); 269 } 270 271 #ifdef USER_LDT 272 273 int 274 linux_read_ldt(p, uap, retval) 275 struct proc *p; 276 struct linux_sys_modify_ldt_args /* { 277 syscallarg(int) func; 278 syscallarg(void *) ptr; 279 syscallarg(size_t) bytecount; 280 } */ *uap; 281 register_t *retval; 282 { 283 struct i386_get_ldt_args gl; 284 int error; 285 caddr_t sg; 286 char *parms; 287 288 sg = stackgap_init(p->p_emul); 289 290 gl.start = 0; 291 gl.desc = SCARG(uap, ptr); 292 gl.num = SCARG(uap, bytecount) / sizeof(union descriptor); 293 294 parms = stackgap_alloc(&sg, sizeof(gl)); 295 296 if ((error = copyout(&gl, parms, sizeof(gl))) != 0) 297 return (error); 298 299 if ((error = i386_get_ldt(p, parms, retval)) != 0) 300 return (error); 301 302 *retval *= sizeof(union descriptor); 303 return (0); 304 } 305 306 struct linux_ldt_info { 307 u_int entry_number; 308 u_long base_addr; 309 u_int limit; 310 u_int seg_32bit:1; 311 u_int contents:2; 312 u_int read_exec_only:1; 313 u_int limit_in_pages:1; 314 u_int seg_not_present:1; 315 }; 316 317 int 318 linux_write_ldt(p, uap, retval) 319 struct proc *p; 320 struct linux_sys_modify_ldt_args /* { 321 syscallarg(int) func; 322 syscallarg(void *) ptr; 323 syscallarg(size_t) bytecount; 324 } */ *uap; 325 register_t *retval; 326 { 327 struct linux_ldt_info ldt_info; 328 struct segment_descriptor sd; 329 struct i386_set_ldt_args sl; 330 int error; 331 caddr_t sg; 332 char *parms; 333 334 if (SCARG(uap, bytecount) != sizeof(ldt_info)) 335 return (EINVAL); 336 if ((error = copyin(SCARG(uap, ptr), &ldt_info, sizeof(ldt_info))) != 0) 337 return error; 338 if (ldt_info.contents == 3) 339 return (EINVAL); 340 341 sg = stackgap_init(p->p_emul); 342 343 sd.sd_lobase = ldt_info.base_addr & 0xffffff; 344 sd.sd_hibase = (ldt_info.base_addr >> 24) & 0xff; 345 sd.sd_lolimit = ldt_info.limit & 0xffff; 346 sd.sd_hilimit = (ldt_info.limit >> 16) & 0xf; 347 sd.sd_type = 348 16 | (ldt_info.contents << 2) | (!ldt_info.read_exec_only << 1); 349 sd.sd_dpl = SEL_UPL; 350 sd.sd_p = !ldt_info.seg_not_present; 351 sd.sd_def32 = ldt_info.seg_32bit; 352 sd.sd_gran = ldt_info.limit_in_pages; 353 354 sl.start = ldt_info.entry_number; 355 sl.desc = stackgap_alloc(&sg, sizeof(sd)); 356 sl.num = 1; 357 358 #if 0 359 printf("linux_write_ldt: idx=%d, base=%x, limit=%x\n", 360 ldt_info.entry_number, ldt_info.base_addr, ldt_info.limit); 361 #endif 362 363 parms = stackgap_alloc(&sg, sizeof(sl)); 364 365 if ((error = copyout(&sd, sl.desc, sizeof(sd))) != 0) 366 return (error); 367 if ((error = copyout(&sl, parms, sizeof(sl))) != 0) 368 return (error); 369 370 if ((error = i386_set_ldt(p, parms, retval)) != 0) 371 return (error); 372 373 *retval = 0; 374 return (0); 375 } 376 377 #endif /* USER_LDT */ 378 379 int 380 linux_sys_modify_ldt(p, v, retval) 381 struct proc *p; 382 void *v; 383 register_t *retval; 384 { 385 struct linux_sys_modify_ldt_args /* { 386 syscallarg(int) func; 387 syscallarg(void *) ptr; 388 syscallarg(size_t) bytecount; 389 } */ *uap = v; 390 391 switch (SCARG(uap, func)) { 392 #ifdef USER_LDT 393 case 0: 394 return (linux_read_ldt(p, uap, retval)); 395 396 case 1: 397 return (linux_write_ldt(p, uap, retval)); 398 #endif /* USER_LDT */ 399 400 default: 401 return (ENOSYS); 402 } 403 } 404 405 /* 406 * XXX Pathetic hack to make svgalib work. This will fake the major 407 * device number of an opened VT so that svgalib likes it. grmbl. 408 * Should probably do it 'wrong the right way' and use a mapping 409 * array for all major device numbers, and map linux_mknod too. 410 */ 411 dev_t 412 linux_fakedev(dev) 413 dev_t dev; 414 { 415 416 if (major(dev) == NETBSD_CONS_MAJOR) 417 return makedev(LINUX_CONS_MAJOR, (minor(dev) + 1)); 418 return dev; 419 } 420 421 /* 422 * We come here in a last attempt to satisfy a Linux ioctl() call 423 */ 424 int 425 linux_machdepioctl(p, v, retval) 426 struct proc *p; 427 void *v; 428 register_t *retval; 429 { 430 struct linux_sys_ioctl_args /* { 431 syscallarg(int) fd; 432 syscallarg(u_long) com; 433 syscallarg(caddr_t) data; 434 } */ *uap = v; 435 struct sys_ioctl_args bia; 436 u_long com; 437 #if NVT > 0 438 int error; 439 struct vt_mode lvt; 440 caddr_t bvtp, sg; 441 #endif 442 443 SCARG(&bia, fd) = SCARG(uap, fd); 444 SCARG(&bia, data) = SCARG(uap, data); 445 com = SCARG(uap, com); 446 447 switch (com) { 448 #if NVT > 0 449 case LINUX_KDGKBMODE: 450 com = KDGKBMODE; 451 break; 452 case LINUX_KDSKBMODE: 453 com = KDSKBMODE; 454 if ((unsigned)SCARG(uap, data) == LINUX_K_MEDIUMRAW) 455 SCARG(&bia, data) = (caddr_t)K_RAW; 456 break; 457 case LINUX_KDMKTONE: 458 com = KDMKTONE; 459 break; 460 case LINUX_KDSETMODE: 461 com = KDSETMODE; 462 break; 463 case LINUX_KDENABIO: 464 com = KDENABIO; 465 break; 466 case LINUX_KDDISABIO: 467 com = KDDISABIO; 468 break; 469 case LINUX_KDGETLED: 470 com = KDGETLED; 471 break; 472 case LINUX_KDSETLED: 473 com = KDSETLED; 474 break; 475 case LINUX_VT_OPENQRY: 476 com = VT_OPENQRY; 477 break; 478 case LINUX_VT_GETMODE: 479 SCARG(&bia, com) = VT_GETMODE; 480 if ((error = sys_ioctl(p, &bia, retval))) 481 return error; 482 if ((error = copyin(SCARG(uap, data), (caddr_t)&lvt, 483 sizeof (struct vt_mode)))) 484 return error; 485 lvt.relsig = bsd_to_linux_sig[lvt.relsig]; 486 lvt.acqsig = bsd_to_linux_sig[lvt.acqsig]; 487 lvt.frsig = bsd_to_linux_sig[lvt.frsig]; 488 return copyout((caddr_t)&lvt, SCARG(uap, data), 489 sizeof (struct vt_mode)); 490 case LINUX_VT_SETMODE: 491 com = VT_SETMODE; 492 if ((error = copyin(SCARG(uap, data), (caddr_t)&lvt, 493 sizeof (struct vt_mode)))) 494 return error; 495 lvt.relsig = linux_to_bsd_sig[lvt.relsig]; 496 lvt.acqsig = linux_to_bsd_sig[lvt.acqsig]; 497 lvt.frsig = linux_to_bsd_sig[lvt.frsig]; 498 sg = stackgap_init(p->p_emul); 499 bvtp = stackgap_alloc(&sg, sizeof (struct vt_mode)); 500 if ((error = copyout(&lvt, bvtp, sizeof (struct vt_mode)))) 501 return error; 502 SCARG(&bia, data) = bvtp; 503 break; 504 case LINUX_VT_RELDISP: 505 com = VT_RELDISP; 506 break; 507 case LINUX_VT_ACTIVATE: 508 com = VT_ACTIVATE; 509 break; 510 case LINUX_VT_WAITACTIVE: 511 com = VT_WAITACTIVE; 512 break; 513 #endif 514 default: 515 printf("linux_machdepioctl: invalid ioctl %08lx\n", com); 516 return EINVAL; 517 } 518 SCARG(&bia, com) = com; 519 return sys_ioctl(p, &bia, retval); 520 } 521 522 /* 523 * Set I/O permissions for a process. Just set the maximum level 524 * right away (ignoring the argument), otherwise we would have 525 * to rely on I/O permission maps, which are not implemented. 526 */ 527 int 528 linux_sys_iopl(p, v, retval) 529 struct proc *p; 530 void *v; 531 register_t *retval; 532 { 533 #if 0 534 struct linux_sys_iopl_args /* { 535 syscallarg(int) level; 536 } */ *uap = v; 537 #endif 538 struct trapframe *fp = p->p_md.md_regs; 539 540 if (suser(p->p_ucred, &p->p_acflag) != 0) 541 return EPERM; 542 fp->tf_eflags |= PSL_IOPL; 543 *retval = 0; 544 return 0; 545 } 546 547 /* 548 * See above. If a root process tries to set access to an I/O port, 549 * just let it have the whole range. 550 */ 551 int 552 linux_sys_ioperm(p, v, retval) 553 struct proc *p; 554 void *v; 555 register_t *retval; 556 { 557 struct linux_sys_ioperm_args /* { 558 syscallarg(unsigned int) lo; 559 syscallarg(unsigned int) hi; 560 syscallarg(int) val; 561 } */ *uap = v; 562 struct trapframe *fp = p->p_md.md_regs; 563 564 if (suser(p->p_ucred, &p->p_acflag) != 0) 565 return EPERM; 566 if (SCARG(uap, val)) 567 fp->tf_eflags |= PSL_IOPL; 568 *retval = 0; 569 return 0; 570 } 571