powerpc: Put FP/VSX and VR state into structures

This creates new 'thread_fp_state' and 'thread_vr_state' structures
to store FP/VSX state (including FPSCR) and Altivec/VSX state
(including VSCR), and uses them in the thread_struct.  In the
thread_fp_state, the FPRs and VSRs are represented as u64 rather
than double, since we rarely perform floating-point computations
on the values, and this will enable the structures to be used
in KVM code as well.  Similarly FPSCR is now a u64 rather than
a structure of two 32-bit values.

This takes the offsets out of the macros such as SAVE_32FPRS,
REST_32FPRS, etc.  This enables the same macros to be used for normal
and transactional state, enabling us to delete the transactional
versions of the macros.   This also removes the unused do_load_up_fpu
and do_load_up_altivec, which were in fact buggy since they didn't
create large enough stack frames to account for the fact that
load_up_fpu and load_up_altivec are not designed to be called from C
and assume that their caller's stack frame is an interrupt frame.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 18 insertions, 22 deletions

diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index ce4de5a..afe695e 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -144,8 +144,20 @@ typedef struct {
 
 #define TS_FPROFFSET 0
 #define TS_VSRLOWOFFSET 1
-#define TS_FPR(i) fpr[i][TS_FPROFFSET]
-#define TS_TRANS_FPR(i) transact_fpr[i][TS_FPROFFSET]
+#define TS_FPR(i) fp_state.fpr[i][TS_FPROFFSET]
+#define TS_TRANS_FPR(i) transact_fp.fpr[i][TS_FPROFFSET]
+
+/* FP and VSX 0-31 register set */
+struct thread_fp_state {
+	u64	fpr[32][TS_FPRWIDTH] __attribute__((aligned(16)));
+	u64	fpscr;		/* Floating point status */
+};
+
+/* Complete AltiVec register set including VSCR */
+struct thread_vr_state {
+	vector128	vr[32] __attribute__((aligned(16)));
+	vector128	vscr __attribute__((aligned(16)));
+};
 
 struct thread_struct {
 	unsigned long	ksp;		/* Kernel stack pointer */
@@ -198,13 +210,7 @@ struct thread_struct {
 	unsigned long	dvc2;
 #endif
 #endif
-	/* FP and VSX 0-31 register set */
-	double		fpr[32][TS_FPRWIDTH] __attribute__((aligned(16)));
-	struct {
-
-		unsigned int pad;
-		unsigned int val;	/* Floating point status */
-	} fpscr;
+	struct thread_fp_state	fp_state;
 	int		fpexc_mode;	/* floating-point exception mode */
 	unsigned int	align_ctl;	/* alignment handling control */
 #ifdef CONFIG_PPC64
@@ -222,10 +228,7 @@ struct thread_struct {
 	struct arch_hw_breakpoint hw_brk; /* info on the hardware breakpoint */
 	unsigned long	trap_nr;	/* last trap # on this thread */
 #ifdef CONFIG_ALTIVEC
-	/* Complete AltiVec register set */
-	vector128	vr[32] __attribute__((aligned(16)));
-	/* AltiVec status */
-	vector128	vscr __attribute__((aligned(16)));
+	struct thread_vr_state vr_state;
 	unsigned long	vrsave;
 	int		used_vr;	/* set if process has used altivec */
 #endif /* CONFIG_ALTIVEC */
@@ -262,13 +265,8 @@ struct thread_struct {
 	 * transact_fpr[] is the new set of transactional values.
 	 * VRs work the same way.
 	 */
-	double		transact_fpr[32][TS_FPRWIDTH];
-	struct {
-		unsigned int pad;
-		unsigned int val;	/* Floating point status */
-	} transact_fpscr;
-	vector128	transact_vr[32] __attribute__((aligned(16)));
-	vector128	transact_vscr __attribute__((aligned(16)));
+	struct thread_fp_state transact_fp;
+	struct thread_vr_state transact_vr;
 	unsigned long	transact_vrsave;
 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
 #ifdef CONFIG_KVM_BOOK3S_32_HANDLER
@@ -322,8 +320,6 @@ struct thread_struct {
 	.ksp = INIT_SP, \
 	.regs = (struct pt_regs *)INIT_SP - 1, /* XXX bogus, I think */ \
 	.fs = KERNEL_DS, \
-	.fpr = {{0}}, \
-	.fpscr = { .val = 0, }, \
 	.fpexc_mode = 0, \
 	.ppr = INIT_PPR, \
 }