linux-user/arm/target_signal.c

/*
 *  Emulation of Linux signals : ARM specific code
 *
 *  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 <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <assert.h>
#include <sys/ucontext.h>
#include <sys/resource.h>

#include "qemu.h"
#include "qemu-common.h"
#include "signal-common.h"
#include "target_signal.h"

struct target_sigcontext {
	abi_ulong trap_no;
	abi_ulong error_code;
	abi_ulong oldmask;
	abi_ulong arm_r0;
	abi_ulong arm_r1;
	abi_ulong arm_r2;
	abi_ulong arm_r3;
	abi_ulong arm_r4;
	abi_ulong arm_r5;
	abi_ulong arm_r6;
	abi_ulong arm_r7;
	abi_ulong arm_r8;
	abi_ulong arm_r9;
	abi_ulong arm_r10;
	abi_ulong arm_fp;
	abi_ulong arm_ip;
	abi_ulong arm_sp;
	abi_ulong arm_lr;
	abi_ulong arm_pc;
	abi_ulong arm_cpsr;
	abi_ulong fault_address;
};

struct target_ucontext_v1 {
    abi_ulong tuc_flags;
    abi_ulong tuc_link;
    target_stack_t tuc_stack;
    struct target_sigcontext tuc_mcontext;
    target_sigset_t  tuc_sigmask;	/* mask last for extensibility */
};

struct target_ucontext_v2 {
    abi_ulong tuc_flags;
    abi_ulong tuc_link;
    target_stack_t tuc_stack;
    struct target_sigcontext tuc_mcontext;
    target_sigset_t  tuc_sigmask;	/* mask last for extensibility */
    char __unused[128 - sizeof(target_sigset_t)];
    abi_ulong tuc_regspace[128] __attribute__((__aligned__(8)));
};

struct target_user_vfp {
    uint64_t fpregs[32];
    abi_ulong fpscr;
};

struct target_user_vfp_exc {
    abi_ulong fpexc;
    abi_ulong fpinst;
    abi_ulong fpinst2;
};

struct target_vfp_sigframe {
    abi_ulong magic;
    abi_ulong size;
    struct target_user_vfp ufp;
    struct target_user_vfp_exc ufp_exc;
} __attribute__((__aligned__(8)));

struct target_iwmmxt_sigframe {
    abi_ulong magic;
    abi_ulong size;
    uint64_t regs[16];
    /* Note that not all the coprocessor control registers are stored here */
    uint32_t wcssf;
    uint32_t wcasf;
    uint32_t wcgr0;
    uint32_t wcgr1;
    uint32_t wcgr2;
    uint32_t wcgr3;
} __attribute__((__aligned__(8)));

#define TARGET_VFP_MAGIC 0x56465001
#define TARGET_IWMMXT_MAGIC 0x12ef842a

struct sigframe_v1
{
    struct target_sigcontext sc;
    abi_ulong extramask[TARGET_NSIG_WORDS-1];
    abi_ulong retcode;
};

struct sigframe_v2
{
    struct target_ucontext_v2 uc;
    abi_ulong retcode;
};

struct rt_sigframe_v1
{
    abi_ulong pinfo;
    abi_ulong puc;
    struct target_siginfo info;
    struct target_ucontext_v1 uc;
    abi_ulong retcode;
};

struct rt_sigframe_v2
{
    struct target_siginfo info;
    struct target_ucontext_v2 uc;
    abi_ulong retcode;
};

#define TARGET_CONFIG_CPU_32 1

/*
 * For ARM syscalls, we encode the syscall number into the instruction.
 */
#define SWI_SYS_SIGRETURN	(0xef000000|(TARGET_NR_sigreturn + ARM_SYSCALL_BASE))
#define SWI_SYS_RT_SIGRETURN	(0xef000000|(TARGET_NR_rt_sigreturn + ARM_SYSCALL_BASE))

/*
 * For Thumb syscalls, we pass the syscall number via r7.  We therefore
 * need two 16-bit instructions.
 */
#define SWI_THUMB_SIGRETURN	(0xdf00 << 16 | 0x2700 | (TARGET_NR_sigreturn))
#define SWI_THUMB_RT_SIGRETURN	(0xdf00 << 16 | 0x2700 | (TARGET_NR_rt_sigreturn))

static const abi_ulong retcodes[4] = {
	SWI_SYS_SIGRETURN,	SWI_THUMB_SIGRETURN,
	SWI_SYS_RT_SIGRETURN,	SWI_THUMB_RT_SIGRETURN
};


#define __get_user_error(x,p,e) __get_user(x, p)

static inline int valid_user_regs(CPUState *regs)
{
    return 1;
}

static void
setup_sigcontext(struct target_sigcontext *sc, /*struct _fpstate *fpstate,*/
		 CPUState *env, abi_ulong mask)
{
	__put_user(env->regs[0], &sc->arm_r0);
	__put_user(env->regs[1], &sc->arm_r1);
	__put_user(env->regs[2], &sc->arm_r2);
	__put_user(env->regs[3], &sc->arm_r3);
	__put_user(env->regs[4], &sc->arm_r4);
	__put_user(env->regs[5], &sc->arm_r5);
	__put_user(env->regs[6], &sc->arm_r6);
	__put_user(env->regs[7], &sc->arm_r7);
	__put_user(env->regs[8], &sc->arm_r8);
	__put_user(env->regs[9], &sc->arm_r9);
	__put_user(env->regs[10], &sc->arm_r10);
	__put_user(env->regs[11], &sc->arm_fp);
	__put_user(env->regs[12], &sc->arm_ip);
	__put_user(env->regs[13], &sc->arm_sp);
	__put_user(env->regs[14], &sc->arm_lr);
	__put_user(env->regs[15], &sc->arm_pc);
#ifdef TARGET_CONFIG_CPU_32
	__put_user(cpsr_read(env), &sc->arm_cpsr);
#endif

	__put_user(/* current->thread.trap_no */ 0, &sc->trap_no);
	__put_user(/* current->thread.error_code */ 0, &sc->error_code);
	__put_user(/* current->thread.address */ 0, &sc->fault_address);
	__put_user(mask, &sc->oldmask);
}

static inline abi_ulong
get_sigframe(struct target_sigaction *ka, CPUState *regs, int framesize)
{
	unsigned long sp = regs->regs[13];

	/*
	 * This is the X/Open sanctioned signal stack switching.
	 */
	if ((ka->sa_flags & TARGET_SA_ONSTACK) && !sas_ss_flags(sp))
            sp = target_sigaltstack_used.ss_sp + target_sigaltstack_used.ss_size;
	/*
	 * ATPCS B01 mandates 8-byte alignment
	 */
	return (sp - framesize) & ~7;
}

static int
setup_return(CPUState *env, struct target_sigaction *ka,
	     abi_ulong *rc, abi_ulong frame_addr, int usig, abi_ulong rc_addr)
{
	abi_ulong handler = ka->_sa_handler;
	abi_ulong retcode;
	int thumb = handler & 1;
	uint32_t cpsr = cpsr_read(env);

	cpsr &= ~CPSR_IT;
	if (thumb) {
		cpsr |= CPSR_T;
	} else {
		cpsr &= ~CPSR_T;
	}

	if (ka->sa_flags & TARGET_SA_RESTORER) {
		retcode = ka->sa_restorer;
	} else {
		unsigned int idx = thumb;

		if (ka->sa_flags & TARGET_SA_SIGINFO)
			idx += 2;

		if (__put_user(retcodes[idx], rc))
			return 1;

		retcode = rc_addr + thumb;
	}

	env->regs[0] = usig;
	env->regs[13] = frame_addr;
	env->regs[14] = retcode;
	env->regs[15] = handler & (thumb ? ~1 : ~3);
	cpsr_write(env, cpsr, 0xffffffff);

	return 0;
}

static abi_ulong *setup_sigframe_v2_vfp(abi_ulong *regspace, CPUState *env)
{
    int i;
    struct target_vfp_sigframe *vfpframe;
    vfpframe = (struct target_vfp_sigframe *)regspace;
    __put_user(TARGET_VFP_MAGIC, &vfpframe->magic);
    __put_user(sizeof(*vfpframe), &vfpframe->size);
    for (i = 0; i < 32; i++) {
        __put_user(float64_val(env->vfp.regs[i]), &vfpframe->ufp.fpregs[i]);
    }
    __put_user(vfp_get_fpscr(env), &vfpframe->ufp.fpscr);
    __put_user(env->vfp.xregs[ARM_VFP_FPEXC], &vfpframe->ufp_exc.fpexc);
    __put_user(env->vfp.xregs[ARM_VFP_FPINST], &vfpframe->ufp_exc.fpinst);
    __put_user(env->vfp.xregs[ARM_VFP_FPINST2], &vfpframe->ufp_exc.fpinst2);
    return (abi_ulong*)(vfpframe+1);
}

static abi_ulong *setup_sigframe_v2_iwmmxt(abi_ulong *regspace, CPUState *env)
{
    int i;
    struct target_iwmmxt_sigframe *iwmmxtframe;
    iwmmxtframe = (struct target_iwmmxt_sigframe *)regspace;
    __put_user(TARGET_IWMMXT_MAGIC, &iwmmxtframe->magic);
    __put_user(sizeof(*iwmmxtframe), &iwmmxtframe->size);
    for (i = 0; i < 16; i++) {
        __put_user(env->iwmmxt.regs[i], &iwmmxtframe->regs[i]);
    }
    __put_user(env->vfp.xregs[ARM_IWMMXT_wCSSF], &iwmmxtframe->wcssf);
    __put_user(env->vfp.xregs[ARM_IWMMXT_wCASF], &iwmmxtframe->wcssf);
    __put_user(env->vfp.xregs[ARM_IWMMXT_wCGR0], &iwmmxtframe->wcgr0);
    __put_user(env->vfp.xregs[ARM_IWMMXT_wCGR1], &iwmmxtframe->wcgr1);
    __put_user(env->vfp.xregs[ARM_IWMMXT_wCGR2], &iwmmxtframe->wcgr2);
    __put_user(env->vfp.xregs[ARM_IWMMXT_wCGR3], &iwmmxtframe->wcgr3);
    return (abi_ulong*)(iwmmxtframe+1);
}

static void setup_sigframe_v2(struct target_ucontext_v2 *uc,
                              target_sigset_t *set, CPUState *env)
{
    struct target_sigaltstack stack;
    int i;
    abi_ulong *regspace;

    /* Clear all the bits of the ucontext we don't use.  */
    memset(uc, 0, offsetof(struct target_ucontext_v2, tuc_mcontext));

    memset(&stack, 0, sizeof(stack));
    __put_user(target_sigaltstack_used.ss_sp, &stack.ss_sp);
    __put_user(target_sigaltstack_used.ss_size, &stack.ss_size);
    __put_user(sas_ss_flags(get_sp_from_cpustate(env)), &stack.ss_flags);
    memcpy(&uc->tuc_stack, &stack, sizeof(stack));

    setup_sigcontext(&uc->tuc_mcontext, env, set->sig[0]);
    /* Save coprocessor signal frame.  */
    regspace = uc->tuc_regspace;
    if (arm_feature(env, ARM_FEATURE_VFP)) {
        regspace = setup_sigframe_v2_vfp(regspace, env);
    }
    if (arm_feature(env, ARM_FEATURE_IWMMXT)) {
        regspace = setup_sigframe_v2_iwmmxt(regspace, env);
    }

    /* Write terminating magic word */
    __put_user(0, regspace);

    for(i = 0; i < TARGET_NSIG_WORDS; i++) {
        __put_user(set->sig[i], &uc->tuc_sigmask.sig[i]);
    }
}

/* compare linux/arch/arm/kernel/signal.c:setup_frame() */
static void setup_frame_v1(int usig, struct target_sigaction *ka,
			   target_sigset_t *set, CPUState *regs)
{
	struct sigframe_v1 *frame;
	abi_ulong frame_addr = get_sigframe(ka, regs, sizeof(*frame));
	int i;

	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
		return;

	setup_sigcontext(&frame->sc, regs, set->sig[0]);

        for(i = 1; i < TARGET_NSIG_WORDS; i++) {
            if (__put_user(set->sig[i], &frame->extramask[i - 1]))
                goto end;
	}

        setup_return(regs, ka, &frame->retcode, frame_addr, usig,
                     frame_addr + offsetof(struct sigframe_v1, retcode));

end:
	unlock_user_struct(frame, frame_addr, 1);
}

static void setup_frame_v2(int usig, struct target_sigaction *ka,
			   target_sigset_t *set, CPUState *regs)
{
	struct sigframe_v2 *frame;
	abi_ulong frame_addr = get_sigframe(ka, regs, sizeof(*frame));

	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
		return;

        setup_sigframe_v2(&frame->uc, set, regs);

        setup_return(regs, ka, &frame->retcode, frame_addr, usig,
                     frame_addr + offsetof(struct sigframe_v2, retcode));

	unlock_user_struct(frame, frame_addr, 1);
}

void setup_frame(int usig, struct target_sigaction *ka,
			target_sigset_t *set, CPUState *regs)
{
    if (get_osversion() >= 0x020612) {
        setup_frame_v2(usig, ka, set, regs);
    } else {
        setup_frame_v1(usig, ka, set, regs);
    }
}

/* compare linux/arch/arm/kernel/signal.c:setup_rt_frame() */
static void setup_rt_frame_v1(int usig, struct target_sigaction *ka,
                              target_siginfo_t *info,
			      target_sigset_t *set, CPUState *env)
{
	struct rt_sigframe_v1 *frame;
	abi_ulong frame_addr = get_sigframe(ka, env, sizeof(*frame));
	struct target_sigaltstack stack;
	int i;
        abi_ulong info_addr, uc_addr;

	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
            return /* 1 */;

        info_addr = frame_addr + offsetof(struct rt_sigframe_v1, info);
	__put_user(info_addr, &frame->pinfo);
        uc_addr = frame_addr + offsetof(struct rt_sigframe_v1, uc);
	__put_user(uc_addr, &frame->puc);
	copy_siginfo_to_user(&frame->info, info);

	/* Clear all the bits of the ucontext we don't use.  */
	memset(&frame->uc, 0, offsetof(struct target_ucontext_v1, tuc_mcontext));

        memset(&stack, 0, sizeof(stack));
        __put_user(target_sigaltstack_used.ss_sp, &stack.ss_sp);
        __put_user(target_sigaltstack_used.ss_size, &stack.ss_size);
        __put_user(sas_ss_flags(get_sp_from_cpustate(env)), &stack.ss_flags);
        memcpy(&frame->uc.tuc_stack, &stack, sizeof(stack));

	setup_sigcontext(&frame->uc.tuc_mcontext, env, set->sig[0]);
        for(i = 0; i < TARGET_NSIG_WORDS; i++) {
            if (__put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]))
                goto end;
        }

        setup_return(env, ka, &frame->retcode, frame_addr, usig,
                     frame_addr + offsetof(struct rt_sigframe_v1, retcode));

        env->regs[1] = info_addr;
        env->regs[2] = uc_addr;

end:
	unlock_user_struct(frame, frame_addr, 1);
}

static void setup_rt_frame_v2(int usig, struct target_sigaction *ka,
                              target_siginfo_t *info,
                              target_sigset_t *set, CPUState *env)
{
	struct rt_sigframe_v2 *frame;
	abi_ulong frame_addr = get_sigframe(ka, env, sizeof(*frame));
        abi_ulong info_addr, uc_addr;

	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
            return /* 1 */;

        info_addr = frame_addr + offsetof(struct rt_sigframe_v2, info);
        uc_addr = frame_addr + offsetof(struct rt_sigframe_v2, uc);
	copy_siginfo_to_user(&frame->info, info);

        setup_sigframe_v2(&frame->uc, set, env);

        setup_return(env, ka, &frame->retcode, frame_addr, usig,
                     frame_addr + offsetof(struct rt_sigframe_v2, retcode));

        env->regs[1] = info_addr;
        env->regs[2] = uc_addr;

	unlock_user_struct(frame, frame_addr, 1);
}

void setup_rt_frame(int usig, struct target_sigaction *ka,
                           target_siginfo_t *info,
			   target_sigset_t *set, CPUState *env)
{
    if (get_osversion() >= 0x020612) {
        setup_rt_frame_v2(usig, ka, info, set, env);
    } else {
        setup_rt_frame_v1(usig, ka, info, set, env);
    }
}

static int
restore_sigcontext(CPUState *env, struct target_sigcontext *sc)
{
	int err = 0;
        uint32_t cpsr;

	__get_user_error(env->regs[0], &sc->arm_r0, err);
	__get_user_error(env->regs[1], &sc->arm_r1, err);
	__get_user_error(env->regs[2], &sc->arm_r2, err);
	__get_user_error(env->regs[3], &sc->arm_r3, err);
	__get_user_error(env->regs[4], &sc->arm_r4, err);
	__get_user_error(env->regs[5], &sc->arm_r5, err);
	__get_user_error(env->regs[6], &sc->arm_r6, err);
	__get_user_error(env->regs[7], &sc->arm_r7, err);
	__get_user_error(env->regs[8], &sc->arm_r8, err);
	__get_user_error(env->regs[9], &sc->arm_r9, err);
	__get_user_error(env->regs[10], &sc->arm_r10, err);
	__get_user_error(env->regs[11], &sc->arm_fp, err);
	__get_user_error(env->regs[12], &sc->arm_ip, err);
	__get_user_error(env->regs[13], &sc->arm_sp, err);
	__get_user_error(env->regs[14], &sc->arm_lr, err);
	__get_user_error(env->regs[15], &sc->arm_pc, err);
#ifdef TARGET_CONFIG_CPU_32
	__get_user_error(cpsr, &sc->arm_cpsr, err);
        cpsr_write(env, cpsr, CPSR_USER | CPSR_EXEC);
#endif

	err |= !valid_user_regs(env);

	return err;
}

static long do_sigreturn_v1(CPUState *env)
{
        abi_ulong frame_addr;
	struct sigframe_v1 *frame;
	target_sigset_t set;
        sigset_t host_set;
        int i;

	/*
	 * Since we stacked the signal on a 64-bit boundary,
	 * then 'sp' should be word aligned here.  If it's
	 * not, then the user is trying to mess with us.
	 */
	if (env->regs[13] & 7)
		goto badframe;

        frame_addr = env->regs[13];
	if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
                goto badframe;

	if (__get_user(set.sig[0], &frame->sc.oldmask))
            goto badframe;
        for(i = 1; i < TARGET_NSIG_WORDS; i++) {
            if (__get_user(set.sig[i], &frame->extramask[i - 1]))
                goto badframe;
        }

        target_to_host_sigset_internal(&host_set, &set);
        sigprocmask(SIG_SETMASK, &host_set, NULL);

	if (restore_sigcontext(env, &frame->sc))
		goto badframe;

#if 0
	/* Send SIGTRAP if we're single-stepping */
	if (ptrace_cancel_bpt(current))
		send_sig(SIGTRAP, current, 1);
#endif
	unlock_user_struct(frame, frame_addr, 0);
        return env->regs[0];

badframe:
	unlock_user_struct(frame, frame_addr, 0);
        force_sig(TARGET_SIGSEGV /* , current */);
	return 0;
}

static abi_ulong *restore_sigframe_v2_vfp(CPUState *env, abi_ulong *regspace)
{
    int i;
    abi_ulong magic, sz;
    uint32_t fpscr, fpexc;
    struct target_vfp_sigframe *vfpframe;
    vfpframe = (struct target_vfp_sigframe *)regspace;

    __get_user(magic, &vfpframe->magic);
    __get_user(sz, &vfpframe->size);
    if (magic != TARGET_VFP_MAGIC || sz != sizeof(*vfpframe)) {
        return 0;
    }
    for (i = 0; i < 32; i++) {
        __get_user(float64_val(env->vfp.regs[i]), &vfpframe->ufp.fpregs[i]);
    }
    __get_user(fpscr, &vfpframe->ufp.fpscr);
    vfp_set_fpscr(env, fpscr);
    __get_user(fpexc, &vfpframe->ufp_exc.fpexc);
    /* Sanitise FPEXC: ensure VFP is enabled, FPINST2 is invalid
     * and the exception flag is cleared
     */
    fpexc |= (1 << 30);
    fpexc &= ~((1 << 31) | (1 << 28));
    env->vfp.xregs[ARM_VFP_FPEXC] = fpexc;
    __get_user(env->vfp.xregs[ARM_VFP_FPINST], &vfpframe->ufp_exc.fpinst);
    __get_user(env->vfp.xregs[ARM_VFP_FPINST2], &vfpframe->ufp_exc.fpinst2);
    return (abi_ulong*)(vfpframe + 1);
}

static abi_ulong *restore_sigframe_v2_iwmmxt(CPUState *env, abi_ulong *regspace)
{
    int i;
    abi_ulong magic, sz;
    struct target_iwmmxt_sigframe *iwmmxtframe;
    iwmmxtframe = (struct target_iwmmxt_sigframe *)regspace;

    __get_user(magic, &iwmmxtframe->magic);
    __get_user(sz, &iwmmxtframe->size);
    if (magic != TARGET_IWMMXT_MAGIC || sz != sizeof(*iwmmxtframe)) {
        return 0;
    }
    for (i = 0; i < 16; i++) {
        __get_user(env->iwmmxt.regs[i], &iwmmxtframe->regs[i]);
    }
    __get_user(env->vfp.xregs[ARM_IWMMXT_wCSSF], &iwmmxtframe->wcssf);
    __get_user(env->vfp.xregs[ARM_IWMMXT_wCASF], &iwmmxtframe->wcssf);
    __get_user(env->vfp.xregs[ARM_IWMMXT_wCGR0], &iwmmxtframe->wcgr0);
    __get_user(env->vfp.xregs[ARM_IWMMXT_wCGR1], &iwmmxtframe->wcgr1);
    __get_user(env->vfp.xregs[ARM_IWMMXT_wCGR2], &iwmmxtframe->wcgr2);
    __get_user(env->vfp.xregs[ARM_IWMMXT_wCGR3], &iwmmxtframe->wcgr3);
    return (abi_ulong*)(iwmmxtframe + 1);
}

static int do_sigframe_return_v2(CPUState *env, target_ulong frame_addr,
                                 struct target_ucontext_v2 *uc)
{
    sigset_t host_set;
    abi_ulong *regspace;

    target_to_host_sigset(&host_set, &uc->tuc_sigmask);
    sigprocmask(SIG_SETMASK, &host_set, NULL);

    if (restore_sigcontext(env, &uc->tuc_mcontext))
        return 1;

    /* Restore coprocessor signal frame */
    regspace = uc->tuc_regspace;
    if (arm_feature(env, ARM_FEATURE_VFP)) {
        regspace = restore_sigframe_v2_vfp(env, regspace);
        if (!regspace) {
            return 1;
        }
    }
    if (arm_feature(env, ARM_FEATURE_IWMMXT)) {
        regspace = restore_sigframe_v2_iwmmxt(env, regspace);
        if (!regspace) {
            return 1;
        }
    }

    if (do_sigaltstack(frame_addr + offsetof(struct target_ucontext_v2, tuc_stack), 0, get_sp_from_cpustate(env)) == -EFAULT)
        return 1;

#if 0
    /* Send SIGTRAP if we're single-stepping */
    if (ptrace_cancel_bpt(current))
            send_sig(SIGTRAP, current, 1);
#endif

    return 0;
}

static long do_sigreturn_v2(CPUState *env)
{
        abi_ulong frame_addr;
	struct sigframe_v2 *frame;

	/*
	 * Since we stacked the signal on a 64-bit boundary,
	 * then 'sp' should be word aligned here.  If it's
	 * not, then the user is trying to mess with us.
	 */
	if (env->regs[13] & 7)
		goto badframe;

        frame_addr = env->regs[13];
	if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
                goto badframe;

        if (do_sigframe_return_v2(env, frame_addr, &frame->uc))
                goto badframe;

	unlock_user_struct(frame, frame_addr, 0);
	return env->regs[0];

badframe:
	unlock_user_struct(frame, frame_addr, 0);
        force_sig(TARGET_SIGSEGV /* , current */);
	return 0;
}

long do_sigreturn(CPUState *env)
{
    if (get_osversion() >= 0x020612) {
        return do_sigreturn_v2(env);
    } else {
        return do_sigreturn_v1(env);
    }
}

static long do_rt_sigreturn_v1(CPUState *env)
{
        abi_ulong frame_addr;
	struct rt_sigframe_v1 *frame;
        sigset_t host_set;

	/*
	 * Since we stacked the signal on a 64-bit boundary,
	 * then 'sp' should be word aligned here.  If it's
	 * not, then the user is trying to mess with us.
	 */
	if (env->regs[13] & 7)
		goto badframe;

        frame_addr = env->regs[13];
	if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
                goto badframe;

        target_to_host_sigset(&host_set, &frame->uc.tuc_sigmask);
        sigprocmask(SIG_SETMASK, &host_set, NULL);

	if (restore_sigcontext(env, &frame->uc.tuc_mcontext))
		goto badframe;

	if (do_sigaltstack(frame_addr + offsetof(struct rt_sigframe_v1, uc.tuc_stack), 0, get_sp_from_cpustate(env)) == -EFAULT)
		goto badframe;

#if 0
	/* Send SIGTRAP if we're single-stepping */
	if (ptrace_cancel_bpt(current))
		send_sig(SIGTRAP, current, 1);
#endif
	unlock_user_struct(frame, frame_addr, 0);
	return env->regs[0];

badframe:
	unlock_user_struct(frame, frame_addr, 0);
        force_sig(TARGET_SIGSEGV /* , current */);
	return 0;
}

static long do_rt_sigreturn_v2(CPUState *env)
{
        abi_ulong frame_addr;
	struct rt_sigframe_v2 *frame;

	/*
	 * Since we stacked the signal on a 64-bit boundary,
	 * then 'sp' should be word aligned here.  If it's
	 * not, then the user is trying to mess with us.
	 */
	if (env->regs[13] & 7)
		goto badframe;

        frame_addr = env->regs[13];
	if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
                goto badframe;

        if (do_sigframe_return_v2(env, frame_addr, &frame->uc))
                goto badframe;

	unlock_user_struct(frame, frame_addr, 0);
	return env->regs[0];

badframe:
	unlock_user_struct(frame, frame_addr, 0);
        force_sig(TARGET_SIGSEGV /* , current */);
	return 0;
}

long do_rt_sigreturn(CPUState *env)
{
    if (get_osversion() >= 0x020612) {
        return do_rt_sigreturn_v2(env);
    } else {
        return do_rt_sigreturn_v1(env);
    }
}