linux-user/s390x/signal.c - third_party/qemu - Git at Google

 /*
  *  Emulation of Linux signals
  *
  *  Copyright (c) 2003 Fabrice Bellard
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 #include "qemu/osdep.h"
 #include "qemu.h"
 #include "signal-common.h"
 #include "linux-user/trace.h"

 #define __NUM_GPRS 16
 #define __NUM_FPRS 16
 #define __NUM_ACRS 16

 #define S390_SYSCALL_SIZE   2
 #define __SIGNAL_FRAMESIZE      160 /* FIXME: 31-bit mode -> 96 */

 #define _SIGCONTEXT_NSIG        64
 #define _SIGCONTEXT_NSIG_BPW    64 /* FIXME: 31-bit mode -> 32 */
 #define _SIGCONTEXT_NSIG_WORDS  (_SIGCONTEXT_NSIG / _SIGCONTEXT_NSIG_BPW)
 #define _SIGMASK_COPY_SIZE    (sizeof(unsigned long)*_SIGCONTEXT_NSIG_WORDS)
 #define PSW_ADDR_AMODE            0x0000000000000000UL /* 0x80000000UL for 31-bit */
 #define S390_SYSCALL_OPCODE ((uint16_t)0x0a00)

 typedef struct {
     target_psw_t psw;
     target_ulong gprs[__NUM_GPRS];
     unsigned int acrs[__NUM_ACRS];
 } target_s390_regs_common;

 typedef struct {
     unsigned int fpc;
     double   fprs[__NUM_FPRS];
 } target_s390_fp_regs;

 typedef struct {
     target_s390_regs_common regs;
     target_s390_fp_regs     fpregs;
 } target_sigregs;

 struct target_sigcontext {
     target_ulong   oldmask[_SIGCONTEXT_NSIG_WORDS];
     target_sigregs *sregs;
 };

 typedef struct {
     uint8_t callee_used_stack[__SIGNAL_FRAMESIZE];
     struct target_sigcontext sc;
     target_sigregs sregs;
     int signo;
     uint8_t retcode[S390_SYSCALL_SIZE];
 } sigframe;

 struct target_ucontext {
     target_ulong tuc_flags;
     struct target_ucontext *tuc_link;
     target_stack_t tuc_stack;
     target_sigregs tuc_mcontext;
     target_sigset_t tuc_sigmask;   /* mask last for extensibility */
 };

 typedef struct {
     uint8_t callee_used_stack[__SIGNAL_FRAMESIZE];
     uint8_t retcode[S390_SYSCALL_SIZE];
     struct target_siginfo info;
     struct target_ucontext uc;
 } rt_sigframe;

 static inline abi_ulong
 get_sigframe(struct target_sigaction *ka, CPUS390XState *env, size_t frame_size)
 {
     abi_ulong sp;

     /* Default to using normal stack */
     sp = get_sp_from_cpustate(env);

     /* This is the X/Open sanctioned signal stack switching.  */
     if (ka->sa_flags & TARGET_SA_ONSTACK) {
         sp = target_sigsp(sp, ka);
     }

     /* This is the legacy signal stack switching. */
     else if (/* FIXME !user_mode(regs) */ 0 &&
              !(ka->sa_flags & TARGET_SA_RESTORER) &&
              ka->sa_restorer) {
         sp = (abi_ulong) ka->sa_restorer;
     }

     return (sp - frame_size) & -8ul;
 }

 static void save_sigregs(CPUS390XState *env, target_sigregs *sregs)
 {
     int i;
     //save_access_regs(current->thread.acrs); FIXME

     /* Copy a 'clean' PSW mask to the user to avoid leaking
        information about whether PER is currently on.  */
     __put_user(env->psw.mask, &sregs->regs.psw.mask);
     __put_user(env->psw.addr, &sregs->regs.psw.addr);
     for (i = 0; i < 16; i++) {
         __put_user(env->regs[i], &sregs->regs.gprs[i]);
     }
     for (i = 0; i < 16; i++) {
         __put_user(env->aregs[i], &sregs->regs.acrs[i]);
     }
     /*
      * We have to store the fp registers to current->thread.fp_regs
      * to merge them with the emulated registers.
      */
     //save_fp_regs(&current->thread.fp_regs); FIXME
     for (i = 0; i < 16; i++) {
         __put_user(*get_freg(env, i), &sregs->fpregs.fprs[i]);
     }
 }

 void setup_frame(int sig, struct target_sigaction *ka,
                  target_sigset_t *set, CPUS390XState *env)
 {
     sigframe *frame;
     abi_ulong frame_addr;

     frame_addr = get_sigframe(ka, env, sizeof(*frame));
     trace_user_setup_frame(env, frame_addr);
     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
         goto give_sigsegv;
     }

     __put_user(set->sig[0], &frame->sc.oldmask[0]);

     save_sigregs(env, &frame->sregs);

     __put_user((abi_ulong)(unsigned long)&frame->sregs,
                (abi_ulong *)&frame->sc.sregs);

     /* Set up to return from userspace.  If provided, use a stub
        already in userspace.  */
     if (ka->sa_flags & TARGET_SA_RESTORER) {
         env->regs[14] = (unsigned long)
                 ka->sa_restorer | PSW_ADDR_AMODE;
     } else {
         env->regs[14] = (frame_addr + offsetof(sigframe, retcode))
                         | PSW_ADDR_AMODE;
         __put_user(S390_SYSCALL_OPCODE | TARGET_NR_sigreturn,
                    (uint16_t *)(frame->retcode));
     }

     /* Set up backchain. */
     __put_user(env->regs[15], (abi_ulong *) frame);

     /* Set up registers for signal handler */
     env->regs[15] = frame_addr;
     env->psw.addr = (target_ulong) ka->_sa_handler | PSW_ADDR_AMODE;

     env->regs[2] = sig; //map_signal(sig);
     env->regs[3] = frame_addr += offsetof(typeof(*frame), sc);

     /* We forgot to include these in the sigcontext.
        To avoid breaking binary compatibility, they are passed as args. */
     env->regs[4] = 0; // FIXME: no clue... current->thread.trap_no;
     env->regs[5] = 0; // FIXME: no clue... current->thread.prot_addr;

     /* Place signal number on stack to allow backtrace from handler.  */
     __put_user(env->regs[2], &frame->signo);
     unlock_user_struct(frame, frame_addr, 1);
     return;

 give_sigsegv:
     force_sigsegv(sig);
 }

 void setup_rt_frame(int sig, struct target_sigaction *ka,
                     target_siginfo_t *info,
                     target_sigset_t *set, CPUS390XState *env)
 {
     int i;
     rt_sigframe *frame;
     abi_ulong frame_addr;

     frame_addr = get_sigframe(ka, env, sizeof *frame);
     trace_user_setup_rt_frame(env, frame_addr);
     if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
         goto give_sigsegv;
     }

     tswap_siginfo(&frame->info, info);

     /* Create the ucontext.  */
     __put_user(0, &frame->uc.tuc_flags);
     __put_user((abi_ulong)0, (abi_ulong *)&frame->uc.tuc_link);
     target_save_altstack(&frame->uc.tuc_stack, env);
     save_sigregs(env, &frame->uc.tuc_mcontext);
     for (i = 0; i < TARGET_NSIG_WORDS; i++) {
         __put_user((abi_ulong)set->sig[i],
                    (abi_ulong *)&frame->uc.tuc_sigmask.sig[i]);
     }

     /* Set up to return from userspace.  If provided, use a stub
        already in userspace.  */
     if (ka->sa_flags & TARGET_SA_RESTORER) {
         env->regs[14] = (unsigned long) ka->sa_restorer | PSW_ADDR_AMODE;
     } else {
         env->regs[14] = (unsigned long) frame->retcode | PSW_ADDR_AMODE;
         __put_user(S390_SYSCALL_OPCODE | TARGET_NR_rt_sigreturn,
                    (uint16_t *)(frame->retcode));
     }

     /* Set up backchain. */
     __put_user(env->regs[15], (abi_ulong *) frame);

     /* Set up registers for signal handler */
     env->regs[15] = frame_addr;
     env->psw.addr = (target_ulong) ka->_sa_handler | PSW_ADDR_AMODE;

     env->regs[2] = sig; //map_signal(sig);
     env->regs[3] = frame_addr + offsetof(typeof(*frame), info);
     env->regs[4] = frame_addr + offsetof(typeof(*frame), uc);
     return;

 give_sigsegv:
     force_sigsegv(sig);
 }

 static int
 restore_sigregs(CPUS390XState *env, target_sigregs *sc)
 {
     int err = 0;
     int i;

     for (i = 0; i < 16; i++) {
         __get_user(env->regs[i], &sc->regs.gprs[i]);
     }

     __get_user(env->psw.mask, &sc->regs.psw.mask);
     trace_user_s390x_restore_sigregs(env, (unsigned long long)sc->regs.psw.addr,
                                      (unsigned long long)env->psw.addr);
     __get_user(env->psw.addr, &sc->regs.psw.addr);
     /* FIXME: 31-bit -> | PSW_ADDR_AMODE */

     for (i = 0; i < 16; i++) {
         __get_user(env->aregs[i], &sc->regs.acrs[i]);
     }
     for (i = 0; i < 16; i++) {
         __get_user(*get_freg(env, i), &sc->fpregs.fprs[i]);
     }

     return err;
 }

 long do_sigreturn(CPUS390XState *env)
 {
     sigframe *frame;
     abi_ulong frame_addr = env->regs[15];
     target_sigset_t target_set;
     sigset_t set;

     trace_user_do_sigreturn(env, frame_addr);
     if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
         goto badframe;
     }
     __get_user(target_set.sig[0], &frame->sc.oldmask[0]);

     target_to_host_sigset_internal(&set, &target_set);
     set_sigmask(&set); /* ~_BLOCKABLE? */

     if (restore_sigregs(env, &frame->sregs)) {
         goto badframe;
     }

     unlock_user_struct(frame, frame_addr, 0);
     return -TARGET_QEMU_ESIGRETURN;

 badframe:
     force_sig(TARGET_SIGSEGV);
     return -TARGET_QEMU_ESIGRETURN;
 }

 long do_rt_sigreturn(CPUS390XState *env)
 {
     rt_sigframe *frame;
     abi_ulong frame_addr = env->regs[15];
     sigset_t set;

     trace_user_do_rt_sigreturn(env, frame_addr);
     if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
         goto badframe;
     }
     target_to_host_sigset(&set, &frame->uc.tuc_sigmask);

     set_sigmask(&set); /* ~_BLOCKABLE? */

     if (restore_sigregs(env, &frame->uc.tuc_mcontext)) {
         goto badframe;
     }

     if (do_sigaltstack(frame_addr + offsetof(rt_sigframe, uc.tuc_stack), 0,
                        get_sp_from_cpustate(env)) == -EFAULT) {
         goto badframe;
     }
     unlock_user_struct(frame, frame_addr, 0);
     return -TARGET_QEMU_ESIGRETURN;

 badframe:
     unlock_user_struct(frame, frame_addr, 0);
     force_sig(TARGET_SIGSEGV);
     return -TARGET_QEMU_ESIGRETURN;
 }
	/*
	* Emulation of Linux signals
	*
	* Copyright (c) 2003 Fabrice Bellard
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, see <http://www.gnu.org/licenses/>.
	*/
	#include "qemu/osdep.h"
	#include "qemu.h"
	#include "signal-common.h"
	#include "linux-user/trace.h"

	#define __NUM_GPRS 16
	#define __NUM_FPRS 16
	#define __NUM_ACRS 16

	#define S390_SYSCALL_SIZE 2
	#define __SIGNAL_FRAMESIZE 160 /* FIXME: 31-bit mode -> 96 */

	#define _SIGCONTEXT_NSIG 64
	#define _SIGCONTEXT_NSIG_BPW 64 /* FIXME: 31-bit mode -> 32 */
	#define _SIGCONTEXT_NSIG_WORDS (_SIGCONTEXT_NSIG / _SIGCONTEXT_NSIG_BPW)
	#define _SIGMASK_COPY_SIZE (sizeof(unsigned long)*_SIGCONTEXT_NSIG_WORDS)
	#define PSW_ADDR_AMODE 0x0000000000000000UL /* 0x80000000UL for 31-bit */
	#define S390_SYSCALL_OPCODE ((uint16_t)0x0a00)

	typedef struct {
	target_psw_t psw;
	target_ulong gprs[__NUM_GPRS];
	unsigned int acrs[__NUM_ACRS];
	} target_s390_regs_common;

	typedef struct {
	unsigned int fpc;
	double fprs[__NUM_FPRS];
	} target_s390_fp_regs;

	typedef struct {
	target_s390_regs_common regs;
	target_s390_fp_regs fpregs;
	} target_sigregs;

	struct target_sigcontext {
	target_ulong oldmask[_SIGCONTEXT_NSIG_WORDS];
	target_sigregs *sregs;
	};

	typedef struct {
	uint8_t callee_used_stack[__SIGNAL_FRAMESIZE];
	struct target_sigcontext sc;
	target_sigregs sregs;
	int signo;
	uint8_t retcode[S390_SYSCALL_SIZE];
	} sigframe;

	struct target_ucontext {
	target_ulong tuc_flags;
	struct target_ucontext *tuc_link;
	target_stack_t tuc_stack;
	target_sigregs tuc_mcontext;
	target_sigset_t tuc_sigmask; /* mask last for extensibility */
	};

	typedef struct {
	uint8_t callee_used_stack[__SIGNAL_FRAMESIZE];
	uint8_t retcode[S390_SYSCALL_SIZE];
	struct target_siginfo info;
	struct target_ucontext uc;
	} rt_sigframe;

	static inline abi_ulong
	get_sigframe(struct target_sigaction ka, CPUS390XState env, size_t frame_size)
	{
	abi_ulong sp;

	/* Default to using normal stack */
	sp = get_sp_from_cpustate(env);

	/* This is the X/Open sanctioned signal stack switching. */
	if (ka->sa_flags & TARGET_SA_ONSTACK) {
	sp = target_sigsp(sp, ka);
	}

	/* This is the legacy signal stack switching. */
	else if (/* FIXME !user_mode(regs) */ 0 &&
	!(ka->sa_flags & TARGET_SA_RESTORER) &&
	ka->sa_restorer) {
	sp = (abi_ulong) ka->sa_restorer;
	}

	return (sp - frame_size) & -8ul;
	}

	static void save_sigregs(CPUS390XState env, target_sigregs sregs)
	{
	int i;
	//save_access_regs(current->thread.acrs); FIXME

	/* Copy a 'clean' PSW mask to the user to avoid leaking
	information about whether PER is currently on. */
	__put_user(env->psw.mask, &sregs->regs.psw.mask);
	__put_user(env->psw.addr, &sregs->regs.psw.addr);
	for (i = 0; i < 16; i++) {
	__put_user(env->regs[i], &sregs->regs.gprs[i]);
	}
	for (i = 0; i < 16; i++) {
	__put_user(env->aregs[i], &sregs->regs.acrs[i]);
	}
	/*
	* We have to store the fp registers to current->thread.fp_regs
	* to merge them with the emulated registers.
	*/
	//save_fp_regs(&current->thread.fp_regs); FIXME
	for (i = 0; i < 16; i++) {
	__put_user(*get_freg(env, i), &sregs->fpregs.fprs[i]);
	}
	}

	void setup_frame(int sig, struct target_sigaction *ka,
	target_sigset_t set, CPUS390XState env)
	{
	sigframe *frame;
	abi_ulong frame_addr;

	frame_addr = get_sigframe(ka, env, sizeof(*frame));
	trace_user_setup_frame(env, frame_addr);
	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
	goto give_sigsegv;
	}

	__put_user(set->sig[0], &frame->sc.oldmask[0]);

	save_sigregs(env, &frame->sregs);

	__put_user((abi_ulong)(unsigned long)&frame->sregs,
	(abi_ulong *)&frame->sc.sregs);

	/* Set up to return from userspace. If provided, use a stub
	already in userspace. */
	if (ka->sa_flags & TARGET_SA_RESTORER) {
	env->regs[14] = (unsigned long)
	ka->sa_restorer \| PSW_ADDR_AMODE;
	} else {
	env->regs[14] = (frame_addr + offsetof(sigframe, retcode))
	\| PSW_ADDR_AMODE;
	__put_user(S390_SYSCALL_OPCODE \| TARGET_NR_sigreturn,
	(uint16_t *)(frame->retcode));
	}

	/* Set up backchain. */
	__put_user(env->regs[15], (abi_ulong *) frame);

	/* Set up registers for signal handler */
	env->regs[15] = frame_addr;
	env->psw.addr = (target_ulong) ka->_sa_handler \| PSW_ADDR_AMODE;

	env->regs[2] = sig; //map_signal(sig);
	env->regs[3] = frame_addr += offsetof(typeof(*frame), sc);

	/* We forgot to include these in the sigcontext.
	To avoid breaking binary compatibility, they are passed as args. */
	env->regs[4] = 0; // FIXME: no clue... current->thread.trap_no;
	env->regs[5] = 0; // FIXME: no clue... current->thread.prot_addr;

	/* Place signal number on stack to allow backtrace from handler. */
	__put_user(env->regs[2], &frame->signo);
	unlock_user_struct(frame, frame_addr, 1);
	return;

	give_sigsegv:
	force_sigsegv(sig);
	}

	void setup_rt_frame(int sig, struct target_sigaction *ka,
	target_siginfo_t *info,
	target_sigset_t set, CPUS390XState env)
	{
	int i;
	rt_sigframe *frame;
	abi_ulong frame_addr;

	frame_addr = get_sigframe(ka, env, sizeof *frame);
	trace_user_setup_rt_frame(env, frame_addr);
	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
	goto give_sigsegv;
	}

	tswap_siginfo(&frame->info, info);

	/* Create the ucontext. */
	__put_user(0, &frame->uc.tuc_flags);
	__put_user((abi_ulong)0, (abi_ulong *)&frame->uc.tuc_link);
	target_save_altstack(&frame->uc.tuc_stack, env);
	save_sigregs(env, &frame->uc.tuc_mcontext);
	for (i = 0; i < TARGET_NSIG_WORDS; i++) {
	__put_user((abi_ulong)set->sig[i],
	(abi_ulong *)&frame->uc.tuc_sigmask.sig[i]);
	}

	/* Set up to return from userspace. If provided, use a stub
	already in userspace. */
	if (ka->sa_flags & TARGET_SA_RESTORER) {
	env->regs[14] = (unsigned long) ka->sa_restorer \| PSW_ADDR_AMODE;
	} else {
	env->regs[14] = (unsigned long) frame->retcode \| PSW_ADDR_AMODE;
	__put_user(S390_SYSCALL_OPCODE \| TARGET_NR_rt_sigreturn,
	(uint16_t *)(frame->retcode));
	}

	/* Set up backchain. */
	__put_user(env->regs[15], (abi_ulong *) frame);

	/* Set up registers for signal handler */
	env->regs[15] = frame_addr;
	env->psw.addr = (target_ulong) ka->_sa_handler \| PSW_ADDR_AMODE;

	env->regs[2] = sig; //map_signal(sig);
	env->regs[3] = frame_addr + offsetof(typeof(*frame), info);
	env->regs[4] = frame_addr + offsetof(typeof(*frame), uc);
	return;

	give_sigsegv:
	force_sigsegv(sig);
	}

	static int
	restore_sigregs(CPUS390XState env, target_sigregs sc)
	{
	int err = 0;
	int i;

	for (i = 0; i < 16; i++) {
	__get_user(env->regs[i], &sc->regs.gprs[i]);
	}

	__get_user(env->psw.mask, &sc->regs.psw.mask);
	trace_user_s390x_restore_sigregs(env, (unsigned long long)sc->regs.psw.addr,
	(unsigned long long)env->psw.addr);
	__get_user(env->psw.addr, &sc->regs.psw.addr);
	/* FIXME: 31-bit -> \| PSW_ADDR_AMODE */

	for (i = 0; i < 16; i++) {
	__get_user(env->aregs[i], &sc->regs.acrs[i]);
	}
	for (i = 0; i < 16; i++) {
	__get_user(*get_freg(env, i), &sc->fpregs.fprs[i]);
	}

	return err;
	}

	long do_sigreturn(CPUS390XState *env)
	{
	sigframe *frame;
	abi_ulong frame_addr = env->regs[15];
	target_sigset_t target_set;
	sigset_t set;

	trace_user_do_sigreturn(env, frame_addr);
	if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
	goto badframe;
	}
	__get_user(target_set.sig[0], &frame->sc.oldmask[0]);

	target_to_host_sigset_internal(&set, &target_set);
	set_sigmask(&set); /* ~_BLOCKABLE? */

	if (restore_sigregs(env, &frame->sregs)) {
	goto badframe;
	}

	unlock_user_struct(frame, frame_addr, 0);
	return -TARGET_QEMU_ESIGRETURN;

	badframe:
	force_sig(TARGET_SIGSEGV);
	return -TARGET_QEMU_ESIGRETURN;
	}

	long do_rt_sigreturn(CPUS390XState *env)
	{
	rt_sigframe *frame;
	abi_ulong frame_addr = env->regs[15];
	sigset_t set;

	trace_user_do_rt_sigreturn(env, frame_addr);
	if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
	goto badframe;
	}
	target_to_host_sigset(&set, &frame->uc.tuc_sigmask);

	set_sigmask(&set); /* ~_BLOCKABLE? */

	if (restore_sigregs(env, &frame->uc.tuc_mcontext)) {
	goto badframe;
	}

	if (do_sigaltstack(frame_addr + offsetof(rt_sigframe, uc.tuc_stack), 0,
	get_sp_from_cpustate(env)) == -EFAULT) {
	goto badframe;
	}
	unlock_user_struct(frame, frame_addr, 0);
	return -TARGET_QEMU_ESIGRETURN;

	badframe:
	unlock_user_struct(frame, frame_addr, 0);
	force_sig(TARGET_SIGSEGV);
	return -TARGET_QEMU_ESIGRETURN;
	}