Commit a03fe725 authored by Maciej W. Rozycki's avatar Maciej W. Rozycki Committed by Ralf Baechle
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MIPS: Factor out NT_PRFPREG regset access helpers 



In preparation to fix a commit 72b22bba ("MIPS: Don't assume 64-bit
FP registers for FP regset") FCSR access regression factor out
NT_PRFPREG regset access helpers for the non-MSA and the MSA variants
respectively, to avoid having to deal with excessive indentation in the
actual fix.

No functional change, however use `target->thread.fpu.fpr[0]' rather
than `target->thread.fpu.fpr[i]' for FGR holding type size determination
as there's no `i' variable to refer to anymore, and for the factored out
`i' variable declaration use `unsigned int' rather than `unsigned' as
its type, following the common style.

Signed-off-by: default avatarMaciej W. Rozycki <macro@mips.com>
Fixes: 72b22bba ("MIPS: Don't assume 64-bit FP registers for FP regset")
Cc: James Hogan <james.hogan@mips.com>
Cc: Paul Burton <Paul.Burton@mips.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org # v3.15+
Patchwork: https://patchwork.linux-mips.org/patch/17925/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 17278a91

arch/mips/kernel/ptrace.c

+83 −25
Original line number Diff line number Diff line
@@ -419,25 +419,36 @@ static int gpr64_set(struct task_struct *target, 


#endif /* CONFIG_64BIT */



static int fpr_get(struct task_struct *target,

		   const struct user_regset *regset,

		   unsigned int pos, unsigned int count,

		   void *kbuf, void __user *ubuf)

/*

 * Copy the floating-point context to the supplied NT_PRFPREG buffer,

 * !CONFIG_CPU_HAS_MSA variant.  FP context's general register slots

 * correspond 1:1 to buffer slots.

 */

static int fpr_get_fpa(struct task_struct *target,

		       unsigned int *pos, unsigned int *count,

		       void **kbuf, void __user **ubuf)

{

	unsigned i;

	int err;

	u64 fpr_val;



	/* XXX fcr31  */



	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))

		return user_regset_copyout(&pos, &count, &kbuf, &ubuf,

	return user_regset_copyout(pos, count, kbuf, ubuf,

				   &target->thread.fpu,

				   0, sizeof(elf_fpregset_t));

}



/*

 * Copy the floating-point context to the supplied NT_PRFPREG buffer,

 * CONFIG_CPU_HAS_MSA variant.  Only lower 64 bits of FP context's

 * general register slots are copied to buffer slots.

 */

static int fpr_get_msa(struct task_struct *target,

		       unsigned int *pos, unsigned int *count,

		       void **kbuf, void __user **ubuf)

{

	unsigned int i;

	u64 fpr_val;

	int err;



	for (i = 0; i < NUM_FPU_REGS; i++) {

		fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);

		err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,

		err = user_regset_copyout(pos, count, kbuf, ubuf,

					  &fpr_val, i * sizeof(elf_fpreg_t),

					  (i + 1) * sizeof(elf_fpreg_t));

		if (err)
@@ -447,27 +458,54 @@ static int fpr_get(struct task_struct *target, 
	return 0;

}



static int fpr_set(struct task_struct *target,

/* Copy the floating-point context to the supplied NT_PRFPREG buffer.  */

static int fpr_get(struct task_struct *target,

		   const struct user_regset *regset,

		   unsigned int pos, unsigned int count,

		   const void *kbuf, const void __user *ubuf)

		   void *kbuf, void __user *ubuf)

{

	unsigned i;

	int err;

	u64 fpr_val;



	/* XXX fcr31  */



	init_fp_ctx(target);

	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))

		err = fpr_get_fpa(target, &pos, &count, &kbuf, &ubuf);

	else

		err = fpr_get_msa(target, &pos, &count, &kbuf, &ubuf);



	return err;

}



	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))

		return user_regset_copyin(&pos, &count, &kbuf, &ubuf,

/*

 * Copy the supplied NT_PRFPREG buffer to the floating-point context,

 * !CONFIG_CPU_HAS_MSA variant.   Buffer slots correspond 1:1 to FP

 * context's general register slots.

 */

static int fpr_set_fpa(struct task_struct *target,

		       unsigned int *pos, unsigned int *count,

		       const void **kbuf, const void __user **ubuf)

{

	return user_regset_copyin(pos, count, kbuf, ubuf,

				  &target->thread.fpu,

				  0, sizeof(elf_fpregset_t));

}



/*

 * Copy the supplied NT_PRFPREG buffer to the floating-point context,

 * CONFIG_CPU_HAS_MSA variant.  Buffer slots are copied to lower 64

 * bits only of FP context's general register slots.

 */

static int fpr_set_msa(struct task_struct *target,

		       unsigned int *pos, unsigned int *count,

		       const void **kbuf, const void __user **ubuf)

{

	unsigned int i;

	u64 fpr_val;

	int err;



	BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));

	for (i = 0; i < NUM_FPU_REGS && count >= sizeof(elf_fpreg_t); i++) {

		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,

	for (i = 0; i < NUM_FPU_REGS && *count >= sizeof(elf_fpreg_t); i++) {

		err = user_regset_copyin(pos, count, kbuf, ubuf,

					 &fpr_val, i * sizeof(elf_fpreg_t),

					 (i + 1) * sizeof(elf_fpreg_t));

		if (err)
@@ -478,6 +516,26 @@ static int fpr_set(struct task_struct *target, 
	return 0;

}



/* Copy the supplied NT_PRFPREG buffer to the floating-point context.  */

static int fpr_set(struct task_struct *target,

		   const struct user_regset *regset,

		   unsigned int pos, unsigned int count,

		   const void *kbuf, const void __user *ubuf)

{

	int err;



	/* XXX fcr31  */



	init_fp_ctx(target);



	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))

		err = fpr_set_fpa(target, &pos, &count, &kbuf, &ubuf);

	else

		err = fpr_set_msa(target, &pos, &count, &kbuf, &ubuf);



	return err;

}



enum mips_regset {

	REGSET_GPR,

	REGSET_FPR,

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