Commit 75779f05 authored by Hiroshi Shimamoto's avatar Hiroshi Shimamoto Committed by Ingo Molnar
Browse files

x86: signal: unify get_sigframe() 



Impact: cleanup

Unify get_sigframe().

Signed-off-by: default avatarHiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 36a45265

arch/x86/kernel/signal.c

+41 −56
Original line number Diff line number Diff line
@@ -187,28 +187,6 @@ setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, 
/*

 * Set up a signal frame.

 */

#ifdef CONFIG_X86_32

static const struct {

	u16 poplmovl;

	u32 val;

	u16 int80;

} __attribute__((packed)) retcode = {

	0xb858,		/* popl %eax; movl $..., %eax */

	__NR_sigreturn,

	0x80cd,		/* int $0x80 */

};



static const struct {

	u8  movl;

	u32 val;

	u16 int80;

	u8  pad;

} __attribute__((packed)) rt_retcode = {

	0xb8,		/* movl $..., %eax */

	__NR_rt_sigreturn,

	0x80cd,		/* int $0x80 */

	0

};



/*

 * Determine which stack to use..
@@ -217,10 +195,13 @@ static inline void __user * 
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,

	     void __user **fpstate)

{

	unsigned long sp;



	/* Default to using normal stack */

	sp = regs->sp;

	unsigned long sp = regs->sp;



#ifdef CONFIG_X86_64

	/* redzone */

	sp -= 128;

#endif /* CONFIG_X86_64 */



	/*

	 * If we are on the alternate signal stack and would overflow it, don't.
@@ -234,30 +215,64 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size, 
		if (sas_ss_flags(sp) == 0)

			sp = current->sas_ss_sp + current->sas_ss_size;

	} else {

#ifdef CONFIG_X86_32

		/* This is the legacy signal stack switching. */

		if ((regs->ss & 0xffff) != __USER_DS &&

			!(ka->sa.sa_flags & SA_RESTORER) &&

				ka->sa.sa_restorer)

			sp = (unsigned long) ka->sa.sa_restorer;

#endif /* CONFIG_X86_32 */

	}



	if (used_math()) {

		sp = sp - sig_xstate_size;

		sp -= sig_xstate_size;

#ifdef CONFIG_X86_32

		*fpstate = (void __user *) sp;

#else /* !CONFIG_X86_32 */

		*fpstate = (void __user *)round_down(sp, 64);

#endif /* CONFIG_X86_32 */



		if (save_i387_xstate(*fpstate) < 0)

			return (void __user *)-1L;

	}



	sp -= frame_size;

#ifdef CONFIG_X86_32

	/*

	 * Align the stack pointer according to the i386 ABI,

	 * i.e. so that on function entry ((sp + 4) & 15) == 0.

	 */

	sp = ((sp + 4) & -16ul) - 4;

#else /* !CONFIG_X86_32 */

	sp = round_down(sp, 16) - 8;

#endif



	return (void __user *) sp;

}



#ifdef CONFIG_X86_32

static const struct {

	u16 poplmovl;

	u32 val;

	u16 int80;

} __attribute__((packed)) retcode = {

	0xb858,		/* popl %eax; movl $..., %eax */

	__NR_sigreturn,

	0x80cd,		/* int $0x80 */

};



static const struct {

	u8  movl;

	u32 val;

	u16 int80;

	u8  pad;

} __attribute__((packed)) rt_retcode = {

	0xb8,		/* movl $..., %eax */

	__NR_rt_sigreturn,

	0x80cd,		/* int $0x80 */

	0

};



static int

__setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,

	      struct pt_regs *regs)
@@ -388,36 +403,6 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 
	return 0;

}

#else /* !CONFIG_X86_32 */

/*

 * Determine which stack to use..

 */

static void __user *

get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,

	     void __user **fpstate)

{

	unsigned long sp;



	/* Default to using normal stack - redzone */

	sp = regs->sp - 128;



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

	if (ka->sa.sa_flags & SA_ONSTACK) {

		if (sas_ss_flags(sp) == 0)

			sp = current->sas_ss_sp + current->sas_ss_size;

	}



	if (used_math()) {

		sp -= sig_xstate_size;

		*fpstate = (void __user *)round_down(sp, 64);



		if (save_i387_xstate(*fpstate) < 0)

			return (void __user *) -1L;

	}



	sp -= frame_size;

	return (void __user *)round_down(sp, 16) - 8;

}



static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,

			    sigset_t *set, struct pt_regs *regs)

{