s390/fpu: remove anonymous union from struct fpu

The anonymous union within struct fpu contains a floating point register
array and a vector register array. Given that the vector register is always
present remove the floating point register array. For configurations
without vector registers save the floating point register contents within
their corresponding vector register location.

This allows to remove the union, and also to simplify ptrace and perf code.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

2 files changed, 63 insertions, 53 deletions

diff --git a/arch/s390/include/asm/fpu-types.h b/arch/s390/include/asm/fpu-types.h
index f5b6fab30401..8e6927c23bdc 100644
--- a/arch/s390/include/asm/fpu-types.h
+++ b/arch/s390/include/asm/fpu-types.h
@@ -12,23 +12,15 @@
 #include <asm/sigcontext.h>
 
 struct fpu {
-	__u32 fpc;		/* Floating-point control */
-	union {
-		/* Floating-point register save area */
-		freg_t fprs[__NUM_FPRS];
-		/* Vector register save area */
-		__vector128 vxrs[__NUM_VXRS];
-	};
+	u32 fpc;
+	__vector128 vxrs[__NUM_VXRS] __aligned(8);
 };
 
 /* In-kernel FPU state structure */
 struct kernel_fpu {
 	int	    mask;
 	u32	    fpc;
-	union {
-		freg_t fprs[__NUM_FPRS];
-		__vector128 vxrs[__NUM_VXRS];
-	};
+	__vector128 vxrs[__NUM_VXRS] __aligned(8);
 };
 
 #define DECLARE_KERNEL_FPU_ONSTACK(name)	\
diff --git a/arch/s390/include/asm/fpu.h b/arch/s390/include/asm/fpu.h
index 4300eef243f9..e706af26c5d0 100644
--- a/arch/s390/include/asm/fpu.h
+++ b/arch/s390/include/asm/fpu.h
@@ -98,44 +98,68 @@ static __always_inline void load_vx_regs(__vector128 *vxrs)
 	fpu_vlm(16, 31, &vxrs[16]);
 }
 
+static __always_inline void __save_fp_regs(freg_t *fprs, unsigned int offset)
+{
+	fpu_std(0, &fprs[0 * offset]);
+	fpu_std(1, &fprs[1 * offset]);
+	fpu_std(2, &fprs[2 * offset]);
+	fpu_std(3, &fprs[3 * offset]);
+	fpu_std(4, &fprs[4 * offset]);
+	fpu_std(5, &fprs[5 * offset]);
+	fpu_std(6, &fprs[6 * offset]);
+	fpu_std(7, &fprs[7 * offset]);
+	fpu_std(8, &fprs[8 * offset]);
+	fpu_std(9, &fprs[9 * offset]);
+	fpu_std(10, &fprs[10 * offset]);
+	fpu_std(11, &fprs[11 * offset]);
+	fpu_std(12, &fprs[12 * offset]);
+	fpu_std(13, &fprs[13 * offset]);
+	fpu_std(14, &fprs[14 * offset]);
+	fpu_std(15, &fprs[15 * offset]);
+}
+
+static __always_inline void __load_fp_regs(freg_t *fprs, unsigned int offset)
+{
+	fpu_ld(0, &fprs[0 * offset]);
+	fpu_ld(1, &fprs[1 * offset]);
+	fpu_ld(2, &fprs[2 * offset]);
+	fpu_ld(3, &fprs[3 * offset]);
+	fpu_ld(4, &fprs[4 * offset]);
+	fpu_ld(5, &fprs[5 * offset]);
+	fpu_ld(6, &fprs[6 * offset]);
+	fpu_ld(7, &fprs[7 * offset]);
+	fpu_ld(8, &fprs[8 * offset]);
+	fpu_ld(9, &fprs[9 * offset]);
+	fpu_ld(10, &fprs[10 * offset]);
+	fpu_ld(11, &fprs[11 * offset]);
+	fpu_ld(12, &fprs[12 * offset]);
+	fpu_ld(13, &fprs[13 * offset]);
+	fpu_ld(14, &fprs[14 * offset]);
+	fpu_ld(15, &fprs[15 * offset]);
+}
+
 static __always_inline void save_fp_regs(freg_t *fprs)
 {
-	fpu_std(0, &fprs[0]);
-	fpu_std(1, &fprs[1]);
-	fpu_std(2, &fprs[2]);
-	fpu_std(3, &fprs[3]);
-	fpu_std(4, &fprs[4]);
-	fpu_std(5, &fprs[5]);
-	fpu_std(6, &fprs[6]);
-	fpu_std(7, &fprs[7]);
-	fpu_std(8, &fprs[8]);
-	fpu_std(9, &fprs[9]);
-	fpu_std(10, &fprs[10]);
-	fpu_std(11, &fprs[11]);
-	fpu_std(12, &fprs[12]);
-	fpu_std(13, &fprs[13]);
-	fpu_std(14, &fprs[14]);
-	fpu_std(15, &fprs[15]);
+	__save_fp_regs(fprs, sizeof(freg_t) / sizeof(freg_t));
 }
 
 static __always_inline void load_fp_regs(freg_t *fprs)
 {
-	fpu_ld(0, &fprs[0]);
-	fpu_ld(1, &fprs[1]);
-	fpu_ld(2, &fprs[2]);
-	fpu_ld(3, &fprs[3]);
-	fpu_ld(4, &fprs[4]);
-	fpu_ld(5, &fprs[5]);
-	fpu_ld(6, &fprs[6]);
-	fpu_ld(7, &fprs[7]);
-	fpu_ld(8, &fprs[8]);
-	fpu_ld(9, &fprs[9]);
-	fpu_ld(10, &fprs[10]);
-	fpu_ld(11, &fprs[11]);
-	fpu_ld(12, &fprs[12]);
-	fpu_ld(13, &fprs[13]);
-	fpu_ld(14, &fprs[14]);
-	fpu_ld(15, &fprs[15]);
+	__load_fp_regs(fprs, sizeof(freg_t) / sizeof(freg_t));
+}
+
+static __always_inline void save_fp_regs_vx(__vector128 *vxrs)
+{
+	freg_t *fprs = (freg_t *)&vxrs[0].high;
+
+	__save_fp_regs(fprs, sizeof(__vector128) / sizeof(freg_t));
+}
+
+static __always_inline void load_fp_regs_vx(__vector128 *vxrs)
+{
+	freg_t *fprs = (freg_t *)&vxrs[0].high;
+
+	__load_fp_regs(fprs, sizeof(__vector128) / sizeof(freg_t));
 }
 
 static inline void kernel_fpu_begin(struct kernel_fpu *state, int flags)
@@ -170,7 +194,7 @@ static inline void save_kernel_fpu_regs(struct thread_struct *thread)
 	if (likely(cpu_has_vx()))
 		save_vx_regs(state->vxrs);
 	else
-		save_fp_regs(state->fprs);
+		save_fp_regs_vx(state->vxrs);
 }
 
 static inline void restore_kernel_fpu_regs(struct thread_struct *thread)
@@ -183,7 +207,7 @@ static inline void restore_kernel_fpu_regs(struct thread_struct *thread)
 	if (likely(cpu_has_vx()))
 		load_vx_regs(state->vxrs);
 	else
-		load_fp_regs(state->fprs);
+		load_fp_regs_vx(state->vxrs);
 }
 
 static inline void convert_vx_to_fp(freg_t *fprs, __vector128 *vxrs)
@@ -206,19 +230,13 @@ static inline void fpregs_store(_s390_fp_regs *fpregs, struct fpu *fpu)
 {
 	fpregs->pad = 0;
 	fpregs->fpc = fpu->fpc;
-	if (cpu_has_vx())
-		convert_vx_to_fp((freg_t *)&fpregs->fprs, fpu->vxrs);
-	else
-		memcpy((freg_t *)&fpregs->fprs, fpu->fprs, sizeof(fpregs->fprs));
+	convert_vx_to_fp((freg_t *)&fpregs->fprs, fpu->vxrs);
 }
 
 static inline void fpregs_load(_s390_fp_regs *fpregs, struct fpu *fpu)
 {
 	fpu->fpc = fpregs->fpc;
-	if (cpu_has_vx())
-		convert_fp_to_vx(fpu->vxrs, (freg_t *)&fpregs->fprs);
-	else
-		memcpy(fpu->fprs, (freg_t *)&fpregs->fprs, sizeof(fpregs->fprs));
+	convert_fp_to_vx(fpu->vxrs, (freg_t *)&fpregs->fprs);
 }
 
 #endif /* _ASM_S390_FPU_H */