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linux_machdep.c revision 1.48.2.1
      1 /*	$NetBSD: linux_machdep.c,v 1.48.2.1 2012/04/17 00:07:15 yamt Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Eric Haszlakiewicz.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  *
     31  * Based on sys/arch/i386/i386/linux_machdep.c:
     32  *	linux_machdep.c,v 1.42 1998/09/11 12:50:06 mycroft Exp
     33  *	written by Frank van der Linden
     34  *
     35  */
     36 
     37 #include <sys/cdefs.h>
     38 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.48.2.1 2012/04/17 00:07:15 yamt Exp $");
     39 
     40 #include <sys/param.h>
     41 #include <sys/systm.h>
     42 #include <sys/signalvar.h>
     43 #include <sys/kernel.h>
     44 #include <sys/proc.h>
     45 #include <sys/buf.h>
     46 #include <sys/reboot.h>
     47 #include <sys/conf.h>
     48 #include <sys/exec.h>
     49 #include <sys/file.h>
     50 #include <sys/callout.h>
     51 #include <sys/malloc.h>
     52 #include <sys/mbuf.h>
     53 #include <sys/msgbuf.h>
     54 #include <sys/mount.h>
     55 #include <sys/vnode.h>
     56 #include <sys/device.h>
     57 #include <sys/syscallargs.h>
     58 #include <sys/filedesc.h>
     59 #include <sys/exec_elf.h>
     60 #include <sys/ioctl.h>
     61 #include <sys/kauth.h>
     62 
     63 #include <uvm/uvm_extern.h>
     64 
     65 #include <compat/linux/common/linux_types.h>
     66 #include <compat/linux/common/linux_signal.h>
     67 #include <compat/linux/common/linux_siginfo.h>
     68 #include <compat/linux/common/linux_util.h>
     69 #include <compat/linux/common/linux_ioctl.h>
     70 #include <compat/linux/common/linux_exec.h>
     71 #include <compat/linux/common/linux_machdep.h>
     72 #include <compat/linux/common/linux_emuldata.h>
     73 
     74 #include <compat/linux/linux_syscallargs.h>
     75 
     76 #include <machine/alpha.h>
     77 #include <machine/reg.h>
     78 
     79 #if defined(_KERNEL_OPT)
     80 #include "wsdisplay.h"
     81 #endif
     82 #if (NWSDISPLAY >0)
     83 #include <dev/wscons/wsdisplay_usl_io.h>
     84 #endif
     85 #ifdef DEBUG
     86 #include <machine/sigdebug.h>
     87 #endif
     88 
     89 /*
     90  * Deal with some alpha-specific things in the Linux emulation code.
     91  */
     92 
     93 void
     94 linux_setregs(struct lwp *l, struct exec_package *epp, vaddr_t stack)
     95 {
     96 #ifdef DEBUG
     97 	struct trapframe *tfp = l->l_md.md_tf;
     98 #endif
     99 
    100 	setregs(l, epp, stack);
    101 #ifdef DEBUG
    102 	/*
    103 	 * Linux has registers set to zero on entry; for DEBUG kernels
    104 	 * the alpha setregs() fills registers with 0xbabefacedeadbeef.
    105 	 */
    106 	memset(tfp->tf_regs, 0, FRAME_SIZE * sizeof tfp->tf_regs[0]);
    107 #endif
    108 }
    109 
    110 void
    111 setup_linux_rt_sigframe(struct trapframe *tf, const ksiginfo_t *ksi,
    112     const sigset_t *mask)
    113 {
    114 	struct lwp *l = curlwp;
    115 	struct proc *p = l->l_proc;
    116 	struct linux_rt_sigframe *sfp, sigframe;
    117 	int onstack, error;
    118 	int fsize, rndfsize;
    119 	int sig = ksi->ksi_signo;
    120 	extern char linux_rt_sigcode[], linux_rt_esigcode[];
    121 
    122 	/* Do we need to jump onto the signal stack? */
    123 	onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
    124 		  (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
    125 
    126 	/* Allocate space for the signal handler context.  */
    127 	fsize = sizeof(struct linux_rt_sigframe);
    128 	rndfsize = ((fsize + 15) / 16) * 16;
    129 
    130 	if (onstack)
    131 		sfp = (struct linux_rt_sigframe *)
    132 		    ((char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size);
    133 	else
    134 		sfp = (struct linux_rt_sigframe *)(alpha_pal_rdusp());
    135 	sfp = (struct linux_rt_sigframe *)((char *)sfp - rndfsize);
    136 
    137 #ifdef DEBUG
    138 	if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
    139 		printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
    140 		    sig, &onstack, sfp);
    141 #endif /* DEBUG */
    142 
    143 	/*
    144 	 * Build the signal context to be used by sigreturn.
    145 	 */
    146 	memset(&sigframe.uc, 0, sizeof(struct linux_ucontext));
    147 	sigframe.uc.uc_mcontext.sc_onstack = onstack;
    148 
    149 	/* Setup potentially partial signal mask in sc_mask. */
    150 	/* But get all of it in uc_sigmask */
    151 	native_to_linux_old_sigset(&sigframe.uc.uc_mcontext.sc_mask, mask);
    152 	native_to_linux_sigset(&sigframe.uc.uc_sigmask, mask);
    153 
    154 	sigframe.uc.uc_mcontext.sc_pc = tf->tf_regs[FRAME_PC];
    155 	sigframe.uc.uc_mcontext.sc_ps = ALPHA_PSL_USERMODE;
    156 	frametoreg(tf, (struct reg *)sigframe.uc.uc_mcontext.sc_regs);
    157 	sigframe.uc.uc_mcontext.sc_regs[R_SP] = alpha_pal_rdusp();
    158 
    159 	fpu_load();
    160 	alpha_pal_wrfen(1);
    161 	sigframe.uc.uc_mcontext.sc_fpcr = alpha_read_fpcr();
    162 	sigframe.uc.uc_mcontext.sc_fp_control = alpha_read_fp_c(l);
    163 	alpha_pal_wrfen(0);
    164 
    165 	sigframe.uc.uc_mcontext.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
    166 	sigframe.uc.uc_mcontext.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
    167 	sigframe.uc.uc_mcontext.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
    168 	native_to_linux_siginfo(&sigframe.info, &ksi->ksi_info);
    169 	sendsig_reset(l, sig);
    170 	mutex_exit(p->p_lock);
    171 	error = copyout((void *)&sigframe, (void *)sfp, fsize);
    172 	mutex_enter(p->p_lock);
    173 
    174 	if (error != 0) {
    175 #ifdef DEBUG
    176 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
    177 			printf("sendsig(%d): copyout failed on sig %d\n",
    178 			    p->p_pid, sig);
    179 #endif
    180 		/*
    181 		 * Process has trashed its stack; give it an illegal
    182 		 * instruction to halt it in its tracks.
    183 		 */
    184 		sigexit(l, SIGILL);
    185 		/* NOTREACHED */
    186 	}
    187 
    188 	/* Pass pointers to siginfo and ucontext in the regs */
    189 	tf->tf_regs[FRAME_A1] = (unsigned long)&sfp->info;
    190 	tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->uc;
    191 
    192 	/* Address of trampoline code.  End up at this PC after mi_switch */
    193 	tf->tf_regs[FRAME_PC] =
    194 	    (u_int64_t)(p->p_psstrp - (linux_rt_esigcode - linux_rt_sigcode));
    195 
    196 	/* Adjust the stack */
    197 	alpha_pal_wrusp((unsigned long)sfp);
    198 
    199 	/* Remember that we're now on the signal stack. */
    200 	if (onstack)
    201 		l->l_sigstk.ss_flags |= SS_ONSTACK;
    202 }
    203 
    204 void setup_linux_sigframe(struct trapframe *tf, const ksiginfo_t *ksi,
    205     const sigset_t *mask)
    206 {
    207 	struct lwp *l = curlwp;
    208 	struct proc *p = l->l_proc;
    209 	struct linux_sigframe *sfp, sigframe;
    210 	int onstack, error;
    211 	int fsize, rndfsize;
    212 	int sig = ksi->ksi_signo;
    213 	extern char linux_sigcode[], linux_esigcode[];
    214 
    215 	/* Do we need to jump onto the signal stack? */
    216 	onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
    217 		  (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
    218 
    219 	/* Allocate space for the signal handler context.  */
    220 	fsize = sizeof(struct linux_sigframe);
    221 	rndfsize = ((fsize + 15) / 16) * 16;
    222 
    223 	if (onstack)
    224 		sfp = (struct linux_sigframe *)
    225 		    ((char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size);
    226 	else
    227 		sfp = (struct linux_sigframe *)(alpha_pal_rdusp());
    228 	sfp = (struct linux_sigframe *)((char *)sfp - rndfsize);
    229 
    230 #ifdef DEBUG
    231 	if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
    232 		printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
    233 		    sig, &onstack, sfp);
    234 #endif /* DEBUG */
    235 
    236 	/*
    237 	 * Build the signal context to be used by sigreturn.
    238 	 */
    239 	memset(&sigframe.sf_sc, 0, sizeof(struct linux_sigcontext));
    240 	sigframe.sf_sc.sc_onstack = onstack;
    241 	native_to_linux_old_sigset(&sigframe.sf_sc.sc_mask, mask);
    242 	sigframe.sf_sc.sc_pc = tf->tf_regs[FRAME_PC];
    243 	sigframe.sf_sc.sc_ps = ALPHA_PSL_USERMODE;
    244 	frametoreg(tf, (struct reg *)sigframe.sf_sc.sc_regs);
    245 	sigframe.sf_sc.sc_regs[R_SP] = alpha_pal_rdusp();
    246 
    247 	if (l == fpcurlwp) {
    248 		struct pcb *pcb = lwp_getpcb(l);
    249 
    250 		alpha_pal_wrfen(1);
    251 		savefpstate(&pcb->pcb_fp);
    252 		alpha_pal_wrfen(0);
    253 		sigframe.sf_sc.sc_fpcr = pcb->pcb_fp.fpr_cr;
    254 		fpcurlwp = NULL;
    255 	}
    256 	/* XXX ownedfp ? etc...? */
    257 
    258 	sigframe.sf_sc.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
    259 	sigframe.sf_sc.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
    260 	sigframe.sf_sc.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
    261 
    262 	sendsig_reset(l, sig);
    263 	mutex_exit(p->p_lock);
    264 	error = copyout((void *)&sigframe, (void *)sfp, fsize);
    265 	mutex_enter(p->p_lock);
    266 
    267 	if (error != 0) {
    268 #ifdef DEBUG
    269 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
    270 			printf("sendsig(%d): copyout failed on sig %d\n",
    271 			    p->p_pid, sig);
    272 #endif
    273 		/*
    274 		 * Process has trashed its stack; give it an illegal
    275 		 * instruction to halt it in its tracks.
    276 		 */
    277 		sigexit(l, SIGILL);
    278 		/* NOTREACHED */
    279 	}
    280 
    281 	/* Pass pointers to sigcontext in the regs */
    282 	tf->tf_regs[FRAME_A1] = 0;
    283 	tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->sf_sc;
    284 
    285 	/* Address of trampoline code.  End up at this PC after mi_switch */
    286 	tf->tf_regs[FRAME_PC] =
    287 	    (u_int64_t)(p->p_psstrp - (linux_esigcode - linux_sigcode));
    288 
    289 	/* Adjust the stack */
    290 	alpha_pal_wrusp((unsigned long)sfp);
    291 
    292 	/* Remember that we're now on the signal stack. */
    293 	if (onstack)
    294 		l->l_sigstk.ss_flags |= SS_ONSTACK;
    295 }
    296 
    297 /*
    298  * Send an interrupt to process.
    299  *
    300  * Stack is set up to allow sigcode stored
    301  * in u. to call routine, followed by kcall
    302  * to sigreturn routine below.  After sigreturn
    303  * resets the signal mask, the stack, and the
    304  * frame pointer, it returns to the user
    305  * specified pc, psl.
    306  */
    307 void
    308 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
    309 {
    310 	struct lwp *l = curlwp;
    311 	struct proc *p = l->l_proc;
    312 	struct trapframe *tf = l->l_md.md_tf;
    313 	const int sig = ksi->ksi_signo;
    314 	sig_t catcher = SIGACTION(p, sig).sa_handler;
    315 #ifdef notyet
    316 	struct linux_emuldata *edp;
    317 
    318 	/* Setup the signal frame (and part of the trapframe) */
    319 	/*OLD: if (p->p_sigacts->ps_siginfo & sigmask(sig))*/
    320 /*	XXX XAX this is broken now.  need someplace to store what
    321 	XXX XAX kind of signal handler a signal has.*/
    322 #if 0
    323 	edp = (struct linux_emuldata *)p->p_emuldata;
    324 #else
    325 	edp = 0;
    326 #endif
    327 	if (edp && sigismember(&edp->ps_siginfo, sig))
    328 		setup_linux_rt_sigframe(tf, ksi, mask);
    329 	else
    330 #endif /* notyet */
    331 		setup_linux_sigframe(tf, ksi, mask);
    332 
    333 	/* Signal handler for trampoline code */
    334 	tf->tf_regs[FRAME_T12] = (u_int64_t)catcher;
    335 	tf->tf_regs[FRAME_A0] = native_to_linux_signo[sig];
    336 
    337 	/*
    338 	 * Linux has a custom restorer option.  To support it we would
    339 	 * need to store an array of restorers and a sigcode block
    340 	 * which knew to use it.  Doesn't seem worth the trouble.
    341 	 * -erh
    342 	 */
    343 
    344 #ifdef DEBUG
    345 	if (sigdebug & SDB_FOLLOW)
    346 		printf("sendsig(%d): pc %lx, catcher %lx\n", l->l_proc->p_pid,
    347 		    tf->tf_regs[FRAME_PC], tf->tf_regs[FRAME_A3]);
    348 	if ((sigdebug & SDB_KSTACK) && l->l_proc->p_pid == sigpid)
    349 		printf("sendsig(%d): sig %d returns\n", l->l_proc->p_pid, sig);
    350 #endif
    351 }
    352 
    353 /*
    354  * System call to cleanup state after a signal
    355  * has been taken.  Reset signal mask and
    356  * stack state from context left by sendsig (above).
    357  * Return to previous pc as specified by context
    358  * left by sendsig.
    359  * Linux real-time signals use a different sigframe,
    360  * but the sigcontext is the same.
    361  */
    362 
    363 int
    364 linux_restore_sigcontext(struct lwp *l, struct linux_sigcontext context,
    365 			 sigset_t *mask)
    366 {
    367 	struct proc *p = l->l_proc;
    368 	struct pcb *pcb;
    369 
    370 	/*
    371 	 * Linux doesn't (yet) have alternate signal stacks.
    372 	 * However, the OSF/1 sigcontext which they use has
    373 	 * an onstack member.  This could be needed in the future.
    374 	 */
    375 	mutex_enter(p->p_lock);
    376 	if (context.sc_onstack & LINUX_SA_ONSTACK)
    377 	    l->l_sigstk.ss_flags |= SS_ONSTACK;
    378 	else
    379 	    l->l_sigstk.ss_flags &= ~SS_ONSTACK;
    380 
    381 	/* Reset the signal mask */
    382 	(void) sigprocmask1(l, SIG_SETMASK, mask, 0);
    383 	mutex_exit(p->p_lock);
    384 
    385 	/*
    386 	 * Check for security violations.
    387 	 * Linux doesn't allow any changes to the PSL.
    388 	 */
    389 	if (context.sc_ps != ALPHA_PSL_USERMODE)
    390 	    return(EINVAL);
    391 
    392 	l->l_md.md_tf->tf_regs[FRAME_PC] = context.sc_pc;
    393 	l->l_md.md_tf->tf_regs[FRAME_PS] = context.sc_ps;
    394 
    395 	regtoframe((struct reg *)context.sc_regs, l->l_md.md_tf);
    396 	alpha_pal_wrusp(context.sc_regs[R_SP]);
    397 
    398 	if (l == fpcurlwp)
    399 	    fpcurlwp = NULL;
    400 
    401 	/* Restore fp regs and fpr_cr */
    402 	pcb = lwp_getpcb(l);
    403 	memcpy(&pcb->pcb_fp, (struct fpreg *)context.sc_fpregs,
    404 	    sizeof(struct fpreg));
    405 	/* XXX sc_ownedfp ? */
    406 	/* XXX sc_fp_control ? */
    407 
    408 #ifdef DEBUG
    409 	if (sigdebug & SDB_FOLLOW)
    410 		printf("linux_rt_sigreturn(%d): returns\n", p->p_pid);
    411 #endif
    412 	return (EJUSTRETURN);
    413 }
    414 
    415 int
    416 linux_sys_rt_sigreturn(struct lwp *l, const struct linux_sys_rt_sigreturn_args *uap, register_t *retval)
    417 {
    418 	/* {
    419 		syscallarg(struct linux_rt_sigframe *) sfp;
    420 	} */
    421 	struct linux_rt_sigframe *sfp, sigframe;
    422 	sigset_t mask;
    423 
    424 	/*
    425 	 * The trampoline code hands us the context.
    426 	 * It is unsafe to keep track of it ourselves, in the event that a
    427 	 * program jumps out of a signal handler.
    428 	 */
    429 
    430 	sfp = SCARG(uap, sfp);
    431 
    432 	if (ALIGN(sfp) != (u_int64_t)sfp)
    433 		return(EINVAL);
    434 
    435 	/*
    436 	 * Fetch the frame structure.
    437 	 */
    438 	if (copyin((void *)sfp, &sigframe,
    439 			sizeof(struct linux_rt_sigframe)) != 0)
    440 		return (EFAULT);
    441 
    442 	/* Grab the signal mask */
    443 	linux_to_native_sigset(&mask, &sigframe.uc.uc_sigmask);
    444 
    445 	return(linux_restore_sigcontext(l, sigframe.uc.uc_mcontext, &mask));
    446 }
    447 
    448 
    449 int
    450 linux_sys_sigreturn(struct lwp *l, const struct linux_sys_sigreturn_args *uap, register_t *retval)
    451 {
    452 	/* {
    453 		syscallarg(struct linux_sigframe *) sfp;
    454 	} */
    455 	struct linux_sigframe *sfp, frame;
    456 	sigset_t mask;
    457 
    458 	/*
    459 	 * The trampoline code hands us the context.
    460 	 * It is unsafe to keep track of it ourselves, in the event that a
    461 	 * program jumps out of a signal handler.
    462 	 */
    463 
    464 	sfp = SCARG(uap, sfp);
    465 	if (ALIGN(sfp) != (u_int64_t)sfp)
    466 		return(EINVAL);
    467 
    468 	/*
    469 	 * Fetch the frame structure.
    470 	 */
    471 	if (copyin((void *)sfp, &frame, sizeof(struct linux_sigframe)) != 0)
    472 		return(EFAULT);
    473 
    474 	/* Grab the signal mask. */
    475 	/* XXX use frame.extramask */
    476 	linux_old_to_native_sigset(&mask, frame.sf_sc.sc_mask);
    477 
    478 	return(linux_restore_sigcontext(l, frame.sf_sc, &mask));
    479 }
    480 
    481 /*
    482  * We come here in a last attempt to satisfy a Linux ioctl() call
    483  */
    484 /* XXX XAX update this, add maps, etc... */
    485 int
    486 linux_machdepioctl(struct lwp *l, const struct linux_sys_ioctl_args *uap, register_t *retval)
    487 {
    488 	/* {
    489 		syscallarg(int) fd;
    490 		syscallarg(u_long) com;
    491 		syscallarg(void *) data;
    492 	} */
    493 	struct sys_ioctl_args bia;
    494 	u_long com;
    495 
    496 	SCARG(&bia, fd) = SCARG(uap, fd);
    497 	SCARG(&bia, data) = SCARG(uap, data);
    498 	com = SCARG(uap, com);
    499 
    500 	switch (com) {
    501 	default:
    502 		printf("linux_machdepioctl: invalid ioctl %08lx\n", com);
    503 		return EINVAL;
    504 	}
    505 	SCARG(&bia, com) = com;
    506 	return sys_ioctl(l, &bia, retval);
    507 }
    508 
    509 /* XXX XAX fix this */
    510 dev_t
    511 linux_fakedev(dev_t dev, int raw)
    512 {
    513 	return dev;
    514 }
    515 
    516 int
    517 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
    518 {
    519 	return 0;
    520 }
    521