Commit 6a274c08 authored by Michael Neuling's avatar Michael Neuling Committed by Paul Mackerras
Browse files

powerpc: Clean up copy_to/from_user for vsx and fpr 



This merges and cleans up some of the ugly copy/to from user code
which is required for the new fpr and vsx layout in the thread_struct.

Also fixes some hard coded buffer sizes and removes a redundant
fpr_flush_to_thread.

Signed-off-by: default avatarMichael Neuling <mikey@neuling.org>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 2d1b2027

arch/powerpc/kernel/signal.h

+10 −0
Original line number Diff line number Diff line
@@ -24,6 +24,16 @@ extern int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka, 
			      siginfo_t *info, sigset_t *oldset,

			      struct pt_regs *regs);



extern unsigned long copy_fpr_to_user(void __user *to,

				      struct task_struct *task);

extern unsigned long copy_fpr_from_user(struct task_struct *task,

					void __user *from);

#ifdef CONFIG_VSX

extern unsigned long copy_vsx_to_user(void __user *to,

				      struct task_struct *task);

extern unsigned long copy_vsx_from_user(struct task_struct *task,

					void __user *from);

#endif



#ifdef CONFIG_PPC64

arch/powerpc/kernel/signal_32.c

+75 −34
Original line number Diff line number Diff line
@@ -328,6 +328,75 @@ struct rt_sigframe { 
	int			abigap[56];

};



#ifdef CONFIG_VSX

unsigned long copy_fpr_to_user(void __user *to,

			       struct task_struct *task)

{

	double buf[ELF_NFPREG];

	int i;



	/* save FPR copy to local buffer then write to the thread_struct */

	for (i = 0; i < (ELF_NFPREG - 1) ; i++)

		buf[i] = task->thread.TS_FPR(i);

	memcpy(&buf[i], &task->thread.fpscr, sizeof(double));

	return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));

}



unsigned long copy_fpr_from_user(struct task_struct *task,

				 void __user *from)

{

	double buf[ELF_NFPREG];

	int i;



	if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))

		return 1;

	for (i = 0; i < (ELF_NFPREG - 1) ; i++)

		task->thread.TS_FPR(i) = buf[i];

	memcpy(&task->thread.fpscr, &buf[i], sizeof(double));



	return 0;

}



unsigned long copy_vsx_to_user(void __user *to,

			       struct task_struct *task)

{

	double buf[ELF_NVSRHALFREG];

	int i;



	/* save FPR copy to local buffer then write to the thread_struct */

	for (i = 0; i < ELF_NVSRHALFREG; i++)

		buf[i] = task->thread.fpr[i][TS_VSRLOWOFFSET];

	return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));

}



unsigned long copy_vsx_from_user(struct task_struct *task,

				 void __user *from)

{

	double buf[ELF_NVSRHALFREG];

	int i;



	if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))

		return 1;

	for (i = 0; i < ELF_NVSRHALFREG ; i++)

		task->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];

	return 0;

}

#else

inline unsigned long copy_fpr_to_user(void __user *to,

				      struct task_struct *task)

{

	return __copy_to_user(to, task->thread.fpr,

			      ELF_NFPREG * sizeof(double));

}



inline unsigned long copy_fpr_from_user(struct task_struct *task,

					void __user *from)

{

	return __copy_from_user(task->thread.fpr, from,

			      ELF_NFPREG * sizeof(double));

}

#endif



/*

 * Save the current user registers on the user stack.

 * We only save the altivec/spe registers if the process has used
@@ -337,10 +406,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, 
		int sigret)

{

	unsigned long msr = regs->msr;

#ifdef CONFIG_VSX

	double buf[32];

	int i;

#endif



	/* Make sure floating point registers are stored in regs */

	flush_fp_to_thread(current);
@@ -370,14 +435,9 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, 
	if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))

		return 1;

#endif /* CONFIG_ALTIVEC */

#ifdef CONFIG_VSX

	/* save FPR copy to local buffer then write to the thread_struct */

	flush_fp_to_thread(current);

	for (i = 0; i < 32 ; i++)

		buf[i] = current->thread.TS_FPR(i);

	memcpy(&buf[i], &current->thread.fpscr, sizeof(double));

	if (__copy_to_user(&frame->mc_fregs, buf, ELF_NFPREG * sizeof(double)))

	if (copy_fpr_to_user(&frame->mc_fregs, current))

		return 1;

#ifdef CONFIG_VSX

	/*

	 * Copy VSR 0-31 upper half from thread_struct to local

	 * buffer, then write that to userspace.  Also set MSR_VSX in
@@ -386,18 +446,10 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, 
	 */

	if (current->thread.used_vsr) {

		flush_vsx_to_thread(current);

		for (i = 0; i < 32 ; i++)

			buf[i] = current->thread.fpr[i][TS_VSRLOWOFFSET];

		if (__copy_to_user(&frame->mc_vsregs, buf,

				   ELF_NVSRHALFREG  * sizeof(double)))

		if (copy_vsx_to_user(&frame->mc_vsregs, current))

			return 1;

		msr |= MSR_VSX;

	}

#else

	/* save floating-point registers */

	if (__copy_to_user(&frame->mc_fregs, current->thread.fpr,

		    ELF_NFPREG * sizeof(double)))

		return 1;

#endif /* CONFIG_VSX */

#ifdef CONFIG_SPE

	/* save spe registers */
@@ -442,7 +494,6 @@ static long restore_user_regs(struct pt_regs *regs, 
	unsigned int save_r2 = 0;

	unsigned long msr;

#ifdef CONFIG_VSX

	double buf[32];

	int i;

#endif
@@ -490,13 +541,10 @@ static long restore_user_regs(struct pt_regs *regs, 
	if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))

		return 1;

#endif /* CONFIG_ALTIVEC */

	if (copy_fpr_from_user(current, &sr->mc_fregs))

		return 1;



#ifdef CONFIG_VSX

	if (__copy_from_user(buf, &sr->mc_fregs,sizeof(sr->mc_fregs)))

		return 1;

	for (i = 0; i < 32 ; i++)

		current->thread.TS_FPR(i) = buf[i];

	memcpy(&current->thread.fpscr, &buf[i], sizeof(double));

	/*

	 * Force the process to reload the VSX registers from

	 * current->thread when it next does VSX instruction.
@@ -507,18 +555,11 @@ static long restore_user_regs(struct pt_regs *regs, 
		 * Restore altivec registers from the stack to a local

		 * buffer, then write this out to the thread_struct

		 */

		if (__copy_from_user(buf, &sr->mc_vsregs,

				     sizeof(sr->mc_vsregs)))

		if (copy_vsx_from_user(current, &sr->mc_vsregs))

			return 1;

		for (i = 0; i < 32 ; i++)

			current->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];

	} else if (current->thread.used_vsr)

		for (i = 0; i < 32 ; i++)

			current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;

#else

	if (__copy_from_user(current->thread.fpr, &sr->mc_fregs,

			     sizeof(sr->mc_fregs)))

		return 1;

#endif /* CONFIG_VSX */

	/*

	 * force the process to reload the FP registers from

arch/powerpc/kernel/signal_64.c

+11 −32
Original line number Diff line number Diff line
@@ -89,10 +89,6 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, 
#endif

	unsigned long msr = regs->msr;

	long err = 0;

#ifdef CONFIG_VSX

	double buf[FP_REGS_SIZE];

	int i;

#endif



	flush_fp_to_thread(current);
@@ -117,12 +113,9 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, 
	err |= __put_user(0, &sc->v_regs);

#endif /* CONFIG_ALTIVEC */

	flush_fp_to_thread(current);

	/* copy fpr regs and fpscr */

	err |= copy_fpr_to_user(&sc->fp_regs, current);

#ifdef CONFIG_VSX

	/* Copy FP to local buffer then write that out */

	for (i = 0; i < 32 ; i++)

		buf[i] = current->thread.TS_FPR(i);

	memcpy(&buf[i], &current->thread.fpscr, sizeof(double));

	err |= __copy_to_user(&sc->fp_regs, buf, FP_REGS_SIZE);

	/*

	 * Copy VSX low doubleword to local buffer for formatting,

	 * then out to userspace.  Update v_regs to point after the
@@ -131,17 +124,12 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, 
	if (current->thread.used_vsr) {

		flush_vsx_to_thread(current);

		v_regs += ELF_NVRREG;

		for (i = 0; i < 32 ; i++)

			buf[i] = current->thread.fpr[i][TS_VSRLOWOFFSET];

		err |= __copy_to_user(v_regs, buf, 32 * sizeof(double));

		err |= copy_vsx_to_user(v_regs, current);

		/* set MSR_VSX in the MSR value in the frame to

		 * indicate that sc->vs_reg) contains valid data.

		 */

		msr |= MSR_VSX;

	}

#else /* CONFIG_VSX */

	/* copy fpr regs and fpscr */

	err |= __copy_to_user(&sc->fp_regs, &current->thread.fpr, FP_REGS_SIZE);

#endif /* CONFIG_VSX */

	err |= __put_user(&sc->gp_regs, &sc->regs);

	WARN_ON(!FULL_REGS(regs));
@@ -164,14 +152,13 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig, 
{

#ifdef CONFIG_ALTIVEC

	elf_vrreg_t __user *v_regs;

#endif

#ifdef CONFIG_VSX

	double buf[FP_REGS_SIZE];

	int i;

#endif

	unsigned long err = 0;

	unsigned long save_r13 = 0;

	unsigned long msr;

#ifdef CONFIG_VSX

	int i;

#endif



	/* If this is not a signal return, we preserve the TLS in r13 */

	if (!sig)
@@ -234,15 +221,9 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig, 
	else

		current->thread.vrsave = 0;

#endif /* CONFIG_ALTIVEC */

#ifdef CONFIG_VSX

	/* restore floating point */

	err |= __copy_from_user(buf, &sc->fp_regs, FP_REGS_SIZE);

	if (err)

		return err;

	for (i = 0; i < 32 ; i++)

		current->thread.TS_FPR(i) = buf[i];

	memcpy(&current->thread.fpscr, &buf[i], sizeof(double));



	err |= copy_fpr_from_user(current, &sc->fp_regs);

#ifdef CONFIG_VSX

	/*

	 * Get additional VSX data. Update v_regs to point after the

	 * VMX data.  Copy VSX low doubleword from userspace to local
@@ -250,14 +231,12 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig, 
	 */

	v_regs += ELF_NVRREG;

	if ((msr & MSR_VSX) != 0)

		err |= __copy_from_user(buf, v_regs, 32 * sizeof(double));

		err |= copy_vsx_from_user(current, v_regs);

	else

		memset(buf, 0, 32 * sizeof(double));



		for (i = 0; i < 32 ; i++)

		current->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];

			current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;



#else

	err |= __copy_from_user(&current->thread.fpr, &sc->fp_regs, FP_REGS_SIZE);

#endif

	return err;

}

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