1 /* $NetBSD: linux_machdep.c,v 1.23 1995/10/10 04:54:25 mycroft 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 61 #include <machine/cpu.h> 62 #include <machine/cpufunc.h> 63 #include <machine/psl.h> 64 #include <machine/reg.h> 65 #include <machine/segments.h> 66 #include <machine/specialreg.h> 67 #include <machine/sysarch.h> 68 #include <machine/linux_machdep.h> 69 70 /* 71 * To see whether pcvt is configured (for virtual console ioctl calls). 72 */ 73 #include "vt.h" 74 #if NVT > 0 75 #include <arch/i386/isa/pcvt/pcvt_ioctl.h> 76 #endif 77 78 /* 79 * Deal with some i386-specific things in the Linux emulation code. 80 * This means just signals for now, will include stuff like 81 * I/O map permissions and V86 mode sometime. 82 */ 83 84 /* 85 * Send an interrupt to process. 86 * 87 * Stack is set up to allow sigcode stored 88 * in u. to call routine, followed by kcall 89 * to sigreturn routine below. After sigreturn 90 * resets the signal mask, the stack, and the 91 * frame pointer, it returns to the user 92 * specified pc, psl. 93 */ 94 95 void 96 linux_sendsig(catcher, sig, mask, code) 97 sig_t catcher; 98 int sig, mask; 99 u_long code; 100 { 101 register struct proc *p = curproc; 102 register struct trapframe *tf; 103 struct linux_sigframe *fp, frame; 104 struct sigacts *psp = p->p_sigacts; 105 int oonstack; 106 extern char linux_sigcode[], linux_esigcode[]; 107 108 tf = p->p_md.md_regs; 109 oonstack = psp->ps_sigstk.ss_flags & SS_ONSTACK; 110 111 /* 112 * Allocate space for the signal handler context. 113 */ 114 if ((psp->ps_flags & SAS_ALTSTACK) && !oonstack && 115 (psp->ps_sigonstack & sigmask(sig))) { 116 fp = (struct linux_sigframe *)(psp->ps_sigstk.ss_base + 117 psp->ps_sigstk.ss_size - sizeof(struct linux_sigframe)); 118 psp->ps_sigstk.ss_flags |= SS_ONSTACK; 119 } else { 120 fp = (struct linux_sigframe *)tf->tf_esp - 1; 121 } 122 123 frame.sf_handler = catcher; 124 frame.sf_sig = bsd_to_linux_sig[sig]; 125 126 /* 127 * Build the signal context to be used by sigreturn. 128 */ 129 frame.sf_sc.sc_mask = mask; 130 #ifdef VM86 131 if (tf->tf_eflags & PSL_VM) { 132 frame.sf_sc.sc_gs = tf->tf_vm86_gs; 133 frame.sf_sc.sc_fs = tf->tf_vm86_fs; 134 frame.sf_sc.sc_es = tf->tf_vm86_es; 135 frame.sf_sc.sc_ds = tf->tf_vm86_ds; 136 } else 137 #endif 138 { 139 __asm("movl %%gs,%w0" : "=r" (frame.sf_sc.sc_gs)); 140 __asm("movl %%fs,%w0" : "=r" (frame.sf_sc.sc_fs)); 141 frame.sf_sc.sc_es = tf->tf_es; 142 frame.sf_sc.sc_ds = tf->tf_ds; 143 } 144 frame.sf_sc.sc_edi = tf->tf_edi; 145 frame.sf_sc.sc_esi = tf->tf_esi; 146 frame.sf_sc.sc_ebp = tf->tf_ebp; 147 frame.sf_sc.sc_ebx = tf->tf_ebx; 148 frame.sf_sc.sc_edx = tf->tf_edx; 149 frame.sf_sc.sc_ecx = tf->tf_ecx; 150 frame.sf_sc.sc_eax = tf->tf_eax; 151 frame.sf_sc.sc_eip = tf->tf_eip; 152 frame.sf_sc.sc_cs = tf->tf_cs; 153 frame.sf_sc.sc_eflags = tf->tf_eflags; 154 frame.sf_sc.sc_esp_at_signal = tf->tf_esp; 155 frame.sf_sc.sc_ss = tf->tf_ss; 156 frame.sf_sc.sc_err = tf->tf_err; 157 frame.sf_sc.sc_trapno = tf->tf_trapno; 158 159 if (copyout(&frame, fp, sizeof(frame)) != 0) { 160 /* 161 * Process has trashed its stack; give it an illegal 162 * instruction to halt it in its tracks. 163 */ 164 sigexit(p, SIGILL); 165 /* NOTREACHED */ 166 } 167 168 /* 169 * Build context to run handler in. 170 */ 171 tf->tf_esp = (int)fp; 172 tf->tf_eip = (int)(((char *)PS_STRINGS) - 173 (linux_esigcode - linux_sigcode)); 174 #ifdef VM86 175 tf->tf_eflags &= ~PSL_VM; 176 #endif 177 tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL); 178 tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL); 179 tf->tf_es = GSEL(GUDATA_SEL, SEL_UPL); 180 tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL); 181 } 182 183 /* 184 * System call to cleanup state after a signal 185 * has been taken. Reset signal mask and 186 * stack state from context left by sendsig (above). 187 * Return to previous pc and psl as specified by 188 * context left by sendsig. Check carefully to 189 * make sure that the user has not modified the 190 * psl to gain improper privileges or to cause 191 * a machine fault. 192 */ 193 int 194 linux_sys_sigreturn(p, v, retval) 195 struct proc *p; 196 void *v; 197 register_t *retval; 198 { 199 struct linux_sys_sigreturn_args /* { 200 syscallarg(struct linux_sigcontext *) scp; 201 } */ *uap = v; 202 struct linux_sigcontext *scp, context; 203 register struct trapframe *tf; 204 205 tf = p->p_md.md_regs; 206 207 /* 208 * The trampoline code hands us the context. 209 * It is unsafe to keep track of it ourselves, in the event that a 210 * program jumps out of a signal handler. 211 */ 212 scp = SCARG(uap, scp); 213 if (copyin((caddr_t)scp, &context, sizeof(*scp)) != 0) 214 return (EFAULT); 215 216 /* 217 * Check for security violations. 218 */ 219 if (((context.sc_eflags ^ tf->tf_eflags) & PSL_USERSTATIC) != 0 || 220 !USERMODE(context.sc_cs, context.sc_eflags)) 221 return (EINVAL); 222 223 p->p_sigacts->ps_sigstk.ss_flags &= ~SS_ONSTACK; 224 p->p_sigmask = context.sc_mask & ~sigcantmask; 225 226 /* 227 * Restore signal context. 228 */ 229 #ifdef VM86 230 if (context.sc_eflags & PSL_VM) { 231 tf->tf_vm86_gs = context.sc_gs; 232 tf->tf_vm86_fs = context.sc_fs; 233 tf->tf_vm86_es = context.sc_es; 234 tf->tf_vm86_ds = context.sc_ds; 235 } else 236 #endif 237 { 238 /* %fs and %gs were restored by the trampoline. */ 239 tf->tf_es = context.sc_es; 240 tf->tf_ds = context.sc_ds; 241 } 242 tf->tf_edi = context.sc_edi; 243 tf->tf_esi = context.sc_esi; 244 tf->tf_ebp = context.sc_ebp; 245 tf->tf_ebx = context.sc_ebx; 246 tf->tf_edx = context.sc_edx; 247 tf->tf_ecx = context.sc_ecx; 248 tf->tf_eax = context.sc_eax; 249 tf->tf_eip = context.sc_eip; 250 tf->tf_cs = context.sc_cs; 251 tf->tf_eflags = context.sc_eflags; 252 tf->tf_esp = context.sc_esp_at_signal; 253 tf->tf_ss = context.sc_ss; 254 255 return (EJUSTRETURN); 256 } 257 258 #ifdef USER_LDT 259 260 int 261 linux_read_ldt(p, uap, retval) 262 struct proc *p; 263 struct linux_sys_modify_ldt_args /* { 264 syscallarg(int) func; 265 syscallarg(void *) ptr; 266 syscallarg(size_t) bytecount; 267 } */ *uap; 268 register_t *retval; 269 { 270 struct i386_get_ldt_args gl; 271 int error; 272 caddr_t sg; 273 char *parms; 274 275 sg = stackgap_init(p->p_emul); 276 277 gl.start = 0; 278 gl.desc = SCARG(uap, ptr); 279 gl.num = SCARG(uap, bytecount) / sizeof(union descriptor); 280 281 parms = stackgap_alloc(&sg, sizeof(gl)); 282 283 if (error = copyout(&gl, parms, sizeof(gl))) 284 return (error); 285 286 if (error = i386_get_ldt(p, parms, retval)) 287 return (error); 288 289 *retval *= sizeof(union descriptor); 290 return (0); 291 } 292 293 struct linux_ldt_info { 294 u_int entry_number; 295 u_long base_addr; 296 u_int limit; 297 u_int seg_32bit:1; 298 u_int contents:2; 299 u_int read_exec_only:1; 300 u_int limit_in_pages:1; 301 u_int seg_not_present:1; 302 }; 303 304 int 305 linux_write_ldt(p, uap, retval) 306 struct proc *p; 307 struct linux_sys_modify_ldt_args /* { 308 syscallarg(int) func; 309 syscallarg(void *) ptr; 310 syscallarg(size_t) bytecount; 311 } */ *uap; 312 register_t *retval; 313 { 314 struct linux_ldt_info ldt_info; 315 struct segment_descriptor sd; 316 struct i386_set_ldt_args sl; 317 int error; 318 caddr_t sg; 319 char *parms; 320 321 if (SCARG(uap, bytecount) != sizeof(ldt_info)) 322 return (EINVAL); 323 if (error = copyin(SCARG(uap, ptr), &ldt_info, sizeof(ldt_info))) 324 return error; 325 if (ldt_info.contents == 3) 326 return (EINVAL); 327 328 sg = stackgap_init(p->p_emul); 329 330 sd.sd_lobase = ldt_info.base_addr & 0xffffff; 331 sd.sd_hibase = (ldt_info.base_addr >> 24) & 0xff; 332 sd.sd_lolimit = ldt_info.limit & 0xffff; 333 sd.sd_hilimit = (ldt_info.limit >> 16) & 0xf; 334 sd.sd_type = 335 16 | (ldt_info.contents << 2) | (!ldt_info.read_exec_only << 1); 336 sd.sd_dpl = SEL_UPL; 337 sd.sd_p = !ldt_info.seg_not_present; 338 sd.sd_def32 = ldt_info.seg_32bit; 339 sd.sd_gran = ldt_info.limit_in_pages; 340 341 sl.start = ldt_info.entry_number; 342 sl.desc = stackgap_alloc(&sg, sizeof(sd)); 343 sl.num = 1; 344 345 #if 0 346 printf("linux_write_ldt: idx=%d, base=%x, limit=%x\n", 347 ldt_info.entry_number, ldt_info.base_addr, ldt_info.limit); 348 #endif 349 350 parms = stackgap_alloc(&sg, sizeof(sl)); 351 352 if (error = copyout(&sd, sl.desc, sizeof(sd))) 353 return (error); 354 if (error = copyout(&sl, parms, sizeof(sl))) 355 return (error); 356 357 if (error = i386_set_ldt(p, parms, retval)) 358 return (error); 359 360 *retval = 0; 361 return (0); 362 } 363 364 #endif /* USER_LDT */ 365 366 int 367 linux_sys_modify_ldt(p, v, retval) 368 struct proc *p; 369 void *v; 370 register_t *retval; 371 { 372 struct linux_sys_modify_ldt_args /* { 373 syscallarg(int) func; 374 syscallarg(void *) ptr; 375 syscallarg(size_t) bytecount; 376 } */ *uap = v; 377 378 switch (SCARG(uap, func)) { 379 #ifdef USER_LDT 380 case 0: 381 return (linux_read_ldt(p, uap, retval)); 382 383 case 1: 384 return (linux_write_ldt(p, uap, retval)); 385 #endif /* USER_LDT */ 386 387 default: 388 return (ENOSYS); 389 } 390 } 391 392 /* 393 * XXX Pathetic hack to make svgalib work. This will fake the major 394 * device number of an opened VT so that svgalib likes it. grmbl. 395 * Should probably do it 'wrong the right way' and use a mapping 396 * array for all major device numbers, and map linux_mknod too. 397 */ 398 dev_t 399 linux_fakedev(dev) 400 dev_t dev; 401 { 402 403 if (major(dev) == NETBSD_CONS_MAJOR) 404 return makedev(LINUX_CONS_MAJOR, (minor(dev) + 1)); 405 return dev; 406 } 407 408 /* 409 * We come here in a last attempt to satisfy a Linux ioctl() call 410 */ 411 int 412 linux_machdepioctl(p, v, retval) 413 struct proc *p; 414 void *v; 415 register_t *retval; 416 { 417 struct linux_sys_ioctl_args /* { 418 syscallarg(int) fd; 419 syscallarg(u_long) com; 420 syscallarg(caddr_t) data; 421 } */ *uap = v; 422 struct sys_ioctl_args bia, tmparg; 423 u_long com; 424 #if NVT > 0 425 int error, mode; 426 struct vt_mode lvt; 427 caddr_t bvtp, sg; 428 u_int fd; 429 struct file *fp; 430 struct filedesc *fdp; 431 #endif 432 433 SCARG(&bia, fd) = SCARG(uap, fd); 434 SCARG(&bia, data) = SCARG(uap, data); 435 com = SCARG(uap, com); 436 437 switch (com) { 438 #if NVT > 0 439 case LINUX_KDGKBMODE: 440 com = KDGKBMODE; 441 break; 442 case LINUX_KDSKBMODE: 443 com = KDSKBMODE; 444 if ((unsigned)SCARG(uap, data) == LINUX_K_MEDIUMRAW) 445 SCARG(&bia, data) = (caddr_t)K_RAW; 446 break; 447 case LINUX_KDMKTONE: 448 com = KDMKTONE; 449 break; 450 case LINUX_KDSETMODE: 451 com = KDSETMODE; 452 break; 453 case LINUX_KDENABIO: 454 com = KDENABIO; 455 break; 456 case LINUX_KDDISABIO: 457 com = KDDISABIO; 458 break; 459 case LINUX_KDGETLED: 460 com = KDGETLED; 461 break; 462 case LINUX_KDSETLED: 463 com = KDSETLED; 464 break; 465 case LINUX_VT_OPENQRY: 466 com = VT_OPENQRY; 467 break; 468 case LINUX_VT_GETMODE: 469 SCARG(&bia, com) = VT_GETMODE; 470 if ((error = sys_ioctl(p, &bia, retval))) 471 return error; 472 if ((error = copyin(SCARG(uap, data), (caddr_t)&lvt, 473 sizeof (struct vt_mode)))) 474 return error; 475 lvt.relsig = bsd_to_linux_sig[lvt.relsig]; 476 lvt.acqsig = bsd_to_linux_sig[lvt.acqsig]; 477 lvt.frsig = bsd_to_linux_sig[lvt.frsig]; 478 return copyout((caddr_t)&lvt, SCARG(uap, data), 479 sizeof (struct vt_mode)); 480 case LINUX_VT_SETMODE: 481 com = VT_SETMODE; 482 if ((error = copyin(SCARG(uap, data), (caddr_t)&lvt, 483 sizeof (struct vt_mode)))) 484 return error; 485 lvt.relsig = linux_to_bsd_sig[lvt.relsig]; 486 lvt.acqsig = linux_to_bsd_sig[lvt.acqsig]; 487 lvt.frsig = linux_to_bsd_sig[lvt.frsig]; 488 sg = stackgap_init(p->p_emul); 489 bvtp = stackgap_alloc(&sg, sizeof (struct vt_mode)); 490 if ((error = copyout(&lvt, bvtp, sizeof (struct vt_mode)))) 491 return error; 492 SCARG(&bia, data) = bvtp; 493 break; 494 case LINUX_VT_RELDISP: 495 com = VT_RELDISP; 496 break; 497 case LINUX_VT_ACTIVATE: 498 com = VT_ACTIVATE; 499 break; 500 case LINUX_VT_WAITACTIVE: 501 com = VT_WAITACTIVE; 502 break; 503 #endif 504 default: 505 return EINVAL; 506 } 507 SCARG(&bia, com) = com; 508 return sys_ioctl(p, &bia, retval); 509 } 510 511 /* 512 * Set I/O permissions for a process. Just set the maximum level 513 * right away (ignoring the argument), otherwise we would have 514 * to rely on I/O permission maps, which are not implemented. 515 */ 516 int 517 linux_sys_iopl(p, v, retval) 518 struct proc *p; 519 void *v; 520 register_t *retval; 521 { 522 struct linux_sys_iopl_args /* { 523 syscallarg(int) level; 524 } */ *uap = v; 525 struct trapframe *fp = p->p_md.md_regs; 526 527 if (suser(p->p_ucred, &p->p_acflag) != 0) 528 return EPERM; 529 fp->tf_eflags |= PSL_IOPL; 530 *retval = 0; 531 return 0; 532 } 533 534 /* 535 * See above. If a root process tries to set access to an I/O port, 536 * just let it have the whole range. 537 */ 538 int 539 linux_sys_ioperm(p, v, retval) 540 struct proc *p; 541 void *v; 542 register_t *retval; 543 { 544 struct linux_sys_ioperm_args /* { 545 syscallarg(unsigned int) lo; 546 syscallarg(unsigned int) hi; 547 syscallarg(int) val; 548 } */ *uap = v; 549 struct trapframe *fp = p->p_md.md_regs; 550 551 if (suser(p->p_ucred, &p->p_acflag) != 0) 552 return EPERM; 553 if (SCARG(uap, val)) 554 fp->tf_eflags |= PSL_IOPL; 555 *retval = 0; 556 return 0; 557 } 558