Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7ecbac74 authored by Greentime Hu's avatar Greentime Hu
Browse files

nds32: Signal handling support 



This patch adds support for signal handling.

Signed-off-by: default avatarVincent Chen <vincentc@andestech.com>
Signed-off-by: default avatarGreentime Hu <greentime@andestech.com>
parent eefacd1d

arch/nds32/include/uapi/asm/sigcontext.h

0 → 100644
+60 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

// Copyright (C) 2005-2017 Andes Technology Corporation



#ifndef _ASMNDS32_SIGCONTEXT_H

#define _ASMNDS32_SIGCONTEXT_H



/*

 * Signal context structure - contains all info to do with the state

 * before the signal handler was invoked.  Note: only add new entries

 * to the end of the structure.

 */



struct zol_struct {

	unsigned long nds32_lc;	/* $LC */

	unsigned long nds32_le;	/* $LE */

	unsigned long nds32_lb;	/* $LB */

};



struct sigcontext {

	unsigned long trap_no;

	unsigned long error_code;

	unsigned long oldmask;

	unsigned long nds32_r0;

	unsigned long nds32_r1;

	unsigned long nds32_r2;

	unsigned long nds32_r3;

	unsigned long nds32_r4;

	unsigned long nds32_r5;

	unsigned long nds32_r6;

	unsigned long nds32_r7;

	unsigned long nds32_r8;

	unsigned long nds32_r9;

	unsigned long nds32_r10;

	unsigned long nds32_r11;

	unsigned long nds32_r12;

	unsigned long nds32_r13;

	unsigned long nds32_r14;

	unsigned long nds32_r15;

	unsigned long nds32_r16;

	unsigned long nds32_r17;

	unsigned long nds32_r18;

	unsigned long nds32_r19;

	unsigned long nds32_r20;

	unsigned long nds32_r21;

	unsigned long nds32_r22;

	unsigned long nds32_r23;

	unsigned long nds32_r24;

	unsigned long nds32_r25;

	unsigned long nds32_fp;	/* $r28 */

	unsigned long nds32_gp;	/* $r29 */

	unsigned long nds32_lp;	/* $r30 */

	unsigned long nds32_sp;	/* $r31 */

	unsigned long nds32_ipc;

	unsigned long fault_address;

	unsigned long used_math_flag;

	/* FPU Registers */

	struct zol_struct zol;

};



#endif

arch/nds32/kernel/signal.c

0 → 100644
+324 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

// Copyright (C) 2005-2017 Andes Technology Corporation



#include <linux/errno.h>

#include <linux/signal.h>

#include <linux/ptrace.h>

#include <linux/personality.h>

#include <linux/freezer.h>

#include <linux/tracehook.h>

#include <linux/uaccess.h>



#include <asm/cacheflush.h>

#include <asm/ucontext.h>

#include <asm/unistd.h>



#include <asm/ptrace.h>

#include <asm/vdso.h>



struct rt_sigframe {

	struct siginfo info;

	struct ucontext uc;

};



static int restore_sigframe(struct pt_regs *regs,

			    struct rt_sigframe __user * sf)

{

	sigset_t set;

	int err;



	err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));

	if (err == 0) {

		set_current_blocked(&set);

	}



	__get_user_error(regs->uregs[0], &sf->uc.uc_mcontext.nds32_r0, err);

	__get_user_error(regs->uregs[1], &sf->uc.uc_mcontext.nds32_r1, err);

	__get_user_error(regs->uregs[2], &sf->uc.uc_mcontext.nds32_r2, err);

	__get_user_error(regs->uregs[3], &sf->uc.uc_mcontext.nds32_r3, err);

	__get_user_error(regs->uregs[4], &sf->uc.uc_mcontext.nds32_r4, err);

	__get_user_error(regs->uregs[5], &sf->uc.uc_mcontext.nds32_r5, err);

	__get_user_error(regs->uregs[6], &sf->uc.uc_mcontext.nds32_r6, err);

	__get_user_error(regs->uregs[7], &sf->uc.uc_mcontext.nds32_r7, err);

	__get_user_error(regs->uregs[8], &sf->uc.uc_mcontext.nds32_r8, err);

	__get_user_error(regs->uregs[9], &sf->uc.uc_mcontext.nds32_r9, err);

	__get_user_error(regs->uregs[10], &sf->uc.uc_mcontext.nds32_r10, err);

	__get_user_error(regs->uregs[11], &sf->uc.uc_mcontext.nds32_r11, err);

	__get_user_error(regs->uregs[12], &sf->uc.uc_mcontext.nds32_r12, err);

	__get_user_error(regs->uregs[13], &sf->uc.uc_mcontext.nds32_r13, err);

	__get_user_error(regs->uregs[14], &sf->uc.uc_mcontext.nds32_r14, err);

	__get_user_error(regs->uregs[15], &sf->uc.uc_mcontext.nds32_r15, err);

	__get_user_error(regs->uregs[16], &sf->uc.uc_mcontext.nds32_r16, err);

	__get_user_error(regs->uregs[17], &sf->uc.uc_mcontext.nds32_r17, err);

	__get_user_error(regs->uregs[18], &sf->uc.uc_mcontext.nds32_r18, err);

	__get_user_error(regs->uregs[19], &sf->uc.uc_mcontext.nds32_r19, err);

	__get_user_error(regs->uregs[20], &sf->uc.uc_mcontext.nds32_r20, err);

	__get_user_error(regs->uregs[21], &sf->uc.uc_mcontext.nds32_r21, err);

	__get_user_error(regs->uregs[22], &sf->uc.uc_mcontext.nds32_r22, err);

	__get_user_error(regs->uregs[23], &sf->uc.uc_mcontext.nds32_r23, err);

	__get_user_error(regs->uregs[24], &sf->uc.uc_mcontext.nds32_r24, err);

	__get_user_error(regs->uregs[25], &sf->uc.uc_mcontext.nds32_r25, err);



	__get_user_error(regs->fp, &sf->uc.uc_mcontext.nds32_fp, err);

	__get_user_error(regs->gp, &sf->uc.uc_mcontext.nds32_gp, err);

	__get_user_error(regs->lp, &sf->uc.uc_mcontext.nds32_lp, err);

	__get_user_error(regs->sp, &sf->uc.uc_mcontext.nds32_sp, err);

	__get_user_error(regs->ipc, &sf->uc.uc_mcontext.nds32_ipc, err);

#if defined(CONFIG_HWZOL)

	__get_user_error(regs->lc, &sf->uc.uc_mcontext.zol.nds32_lc, err);

	__get_user_error(regs->le, &sf->uc.uc_mcontext.zol.nds32_le, err);

	__get_user_error(regs->lb, &sf->uc.uc_mcontext.zol.nds32_lb, err);

#endif



	/*

	 * Avoid sys_rt_sigreturn() restarting.

	 */

	forget_syscall(regs);

	return err;

}



asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)

{

	struct rt_sigframe __user *frame;



	/* Always make any pending restarted system calls return -EINTR */

	current->restart_block.fn = do_no_restart_syscall;



	/*

	 * Since we stacked the signal on a 64-bit boundary,

	 * then 'sp' should be two-word aligned here.  If it's

	 * not, then the user is trying to mess with us.

	 */

	if (regs->sp & 7)

		goto badframe;



	frame = (struct rt_sigframe __user *)regs->sp;



	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))

		goto badframe;



	if (restore_sigframe(regs, frame))

		goto badframe;



	if (restore_altstack(&frame->uc.uc_stack))

		goto badframe;



	return regs->uregs[0];



badframe:

	force_sig(SIGSEGV, current);

	return 0;

}



static int

setup_sigframe(struct rt_sigframe __user * sf, struct pt_regs *regs,

	       sigset_t * set)

{

	int err = 0;



	__put_user_error(regs->uregs[0], &sf->uc.uc_mcontext.nds32_r0, err);

	__put_user_error(regs->uregs[1], &sf->uc.uc_mcontext.nds32_r1, err);

	__put_user_error(regs->uregs[2], &sf->uc.uc_mcontext.nds32_r2, err);

	__put_user_error(regs->uregs[3], &sf->uc.uc_mcontext.nds32_r3, err);

	__put_user_error(regs->uregs[4], &sf->uc.uc_mcontext.nds32_r4, err);

	__put_user_error(regs->uregs[5], &sf->uc.uc_mcontext.nds32_r5, err);

	__put_user_error(regs->uregs[6], &sf->uc.uc_mcontext.nds32_r6, err);

	__put_user_error(regs->uregs[7], &sf->uc.uc_mcontext.nds32_r7, err);

	__put_user_error(regs->uregs[8], &sf->uc.uc_mcontext.nds32_r8, err);

	__put_user_error(regs->uregs[9], &sf->uc.uc_mcontext.nds32_r9, err);

	__put_user_error(regs->uregs[10], &sf->uc.uc_mcontext.nds32_r10, err);

	__put_user_error(regs->uregs[11], &sf->uc.uc_mcontext.nds32_r11, err);

	__put_user_error(regs->uregs[12], &sf->uc.uc_mcontext.nds32_r12, err);

	__put_user_error(regs->uregs[13], &sf->uc.uc_mcontext.nds32_r13, err);

	__put_user_error(regs->uregs[14], &sf->uc.uc_mcontext.nds32_r14, err);

	__put_user_error(regs->uregs[15], &sf->uc.uc_mcontext.nds32_r15, err);

	__put_user_error(regs->uregs[16], &sf->uc.uc_mcontext.nds32_r16, err);

	__put_user_error(regs->uregs[17], &sf->uc.uc_mcontext.nds32_r17, err);

	__put_user_error(regs->uregs[18], &sf->uc.uc_mcontext.nds32_r18, err);

	__put_user_error(regs->uregs[19], &sf->uc.uc_mcontext.nds32_r19, err);

	__put_user_error(regs->uregs[20], &sf->uc.uc_mcontext.nds32_r20, err);



	__put_user_error(regs->uregs[21], &sf->uc.uc_mcontext.nds32_r21, err);

	__put_user_error(regs->uregs[22], &sf->uc.uc_mcontext.nds32_r22, err);

	__put_user_error(regs->uregs[23], &sf->uc.uc_mcontext.nds32_r23, err);

	__put_user_error(regs->uregs[24], &sf->uc.uc_mcontext.nds32_r24, err);

	__put_user_error(regs->uregs[25], &sf->uc.uc_mcontext.nds32_r25, err);

	__put_user_error(regs->fp, &sf->uc.uc_mcontext.nds32_fp, err);

	__put_user_error(regs->gp, &sf->uc.uc_mcontext.nds32_gp, err);

	__put_user_error(regs->lp, &sf->uc.uc_mcontext.nds32_lp, err);

	__put_user_error(regs->sp, &sf->uc.uc_mcontext.nds32_sp, err);

	__put_user_error(regs->ipc, &sf->uc.uc_mcontext.nds32_ipc, err);

#if defined(CONFIG_HWZOL)

	__put_user_error(regs->lc, &sf->uc.uc_mcontext.zol.nds32_lc, err);

	__put_user_error(regs->le, &sf->uc.uc_mcontext.zol.nds32_le, err);

	__put_user_error(regs->lb, &sf->uc.uc_mcontext.zol.nds32_lb, err);

#endif



	__put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no,

			 err);

	__put_user_error(current->thread.error_code,

			 &sf->uc.uc_mcontext.error_code, err);

	__put_user_error(current->thread.address,

			 &sf->uc.uc_mcontext.fault_address, err);

	__put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err);



	err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));



	return err;

}



static inline void __user *get_sigframe(struct ksignal *ksig,

					struct pt_regs *regs, int framesize)

{

	unsigned long sp;



	/* Default to using normal stack */

	sp = regs->sp;



	/*

	 * If we are on the alternate signal stack and would overflow it, don't.

	 * Return an always-bogus address instead so we will die with SIGSEGV.

	 */

	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))

		return (void __user __force *)(-1UL);



	/* This is the X/Open sanctioned signal stack switching. */

	sp = (sigsp(sp, ksig) - framesize);



	/*

	 * nds32 mandates 8-byte alignment

	 */

	sp &= ~0x7UL;



	return (void __user *)sp;

}



static int

setup_return(struct pt_regs *regs, struct ksignal *ksig, void __user * frame)

{

	unsigned long handler = (unsigned long)ksig->ka.sa.sa_handler;

	unsigned long retcode;



	retcode = VDSO_SYMBOL(current->mm->context.vdso, rt_sigtramp);

	regs->uregs[0] = ksig->sig;

	regs->sp = (unsigned long)frame;

	regs->lp = retcode;

	regs->ipc = handler;



	return 0;

}



static int

setup_rt_frame(struct ksignal *ksig, sigset_t * set, struct pt_regs *regs)

{

	struct rt_sigframe __user *frame =

	    get_sigframe(ksig, regs, sizeof(*frame));

	int err = 0;



	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))

		return -EFAULT;



	__put_user_error(0, &frame->uc.uc_flags, err);

	__put_user_error(NULL, &frame->uc.uc_link, err);



	err |= __save_altstack(&frame->uc.uc_stack, regs->sp);

	err |= setup_sigframe(frame, regs, set);

	if (err == 0) {

		setup_return(regs, ksig, frame);

		if (ksig->ka.sa.sa_flags & SA_SIGINFO) {

			err |= copy_siginfo_to_user(&frame->info, &ksig->info);

			regs->uregs[1] = (unsigned long)&frame->info;

			regs->uregs[2] = (unsigned long)&frame->uc;

		}

	}

	return err;

}



/*

 * OK, we're invoking a handler

 */

static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)

{

	int ret;

	sigset_t *oldset = sigmask_to_save();



	if (in_syscall(regs)) {

		/* Avoid additional syscall restarting via ret_slow_syscall. */

		forget_syscall(regs);



		switch (regs->uregs[0]) {

		case -ERESTART_RESTARTBLOCK:

		case -ERESTARTNOHAND:

			regs->uregs[0] = -EINTR;

			break;

		case -ERESTARTSYS:

			if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {

				regs->uregs[0] = -EINTR;

				break;

			}

		case -ERESTARTNOINTR:

			regs->uregs[0] = regs->orig_r0;

			regs->ipc -= 4;

			break;

		}

	}

	/*

	 * Set up the stack frame

	 */

	ret = setup_rt_frame(ksig, oldset, regs);



	signal_setup_done(ret, ksig, 0);

}



/*

 * Note that 'init' is a special process: it doesn't get signals it doesn't

 * want to handle. Thus you cannot kill init even with a SIGKILL even by

 * mistake.

 *

 * Note that we go through the signals twice: once to check the signals that

 * the kernel can handle, and then we build all the user-level signal handling

 * stack-frames in one go after that.

 */

static void do_signal(struct pt_regs *regs)

{

	struct ksignal ksig;



	if (get_signal(&ksig)) {

		handle_signal(&ksig, regs);

		return;

	}



	/*

	 * If we were from a system call, check for system call restarting...

	 */

	if (in_syscall(regs)) {

		/* Restart the system call - no handlers present */



		/* Avoid additional syscall restarting via ret_slow_syscall. */

		forget_syscall(regs);



		switch (regs->uregs[0]) {

		case -ERESTART_RESTARTBLOCK:

			regs->uregs[15] = __NR_restart_syscall;

		case -ERESTARTNOHAND:

		case -ERESTARTSYS:

		case -ERESTARTNOINTR:

			regs->uregs[0] = regs->orig_r0;

			regs->ipc -= 0x4;

			break;

		}

	}

	restore_saved_sigmask();

}



asmlinkage void

do_notify_resume(struct pt_regs *regs, unsigned int thread_flags)

{

	if (thread_flags & _TIF_SIGPENDING)

		do_signal(regs);



	if (thread_flags & _TIF_NOTIFY_RESUME) {

		clear_thread_flag(TIF_NOTIFY_RESUME);

		tracehook_notify_resume(regs);

	}

}