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, 8 insertions, 17 deletions

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 502c7a4e73f7..8d27b61c95b9 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -90,16 +90,15 @@ int main(void)
 	DEFINE(THREAD_NORMSAVES, offsetof(struct thread_struct, normsave[0]));
 #endif
 	DEFINE(THREAD_FPEXC_MODE, offsetof(struct thread_struct, fpexc_mode));
-	DEFINE(THREAD_FPR0, offsetof(struct thread_struct, fpr[0]));
-	DEFINE(THREAD_FPSCR, offsetof(struct thread_struct, fpscr));
+	DEFINE(THREAD_FPSTATE, offsetof(struct thread_struct, fp_state));
+	DEFINE(FPSTATE_FPSCR, offsetof(struct thread_fp_state, fpscr));
 #ifdef CONFIG_ALTIVEC
-	DEFINE(THREAD_VR0, offsetof(struct thread_struct, vr[0]));
+	DEFINE(THREAD_VRSTATE, offsetof(struct thread_struct, vr_state));
 	DEFINE(THREAD_VRSAVE, offsetof(struct thread_struct, vrsave));
-	DEFINE(THREAD_VSCR, offsetof(struct thread_struct, vscr));
 	DEFINE(THREAD_USED_VR, offsetof(struct thread_struct, used_vr));
+	DEFINE(VRSTATE_VSCR, offsetof(struct thread_vr_state, vscr));
 #endif /* CONFIG_ALTIVEC */
 #ifdef CONFIG_VSX
-	DEFINE(THREAD_VSR0, offsetof(struct thread_struct, fpr));
 	DEFINE(THREAD_USED_VSR, offsetof(struct thread_struct, used_vsr));
 #endif /* CONFIG_VSX */
 #ifdef CONFIG_PPC64
@@ -143,20 +142,12 @@ int main(void)
 	DEFINE(THREAD_TM_PPR, offsetof(struct thread_struct, tm_ppr));
 	DEFINE(THREAD_TM_DSCR, offsetof(struct thread_struct, tm_dscr));
 	DEFINE(PT_CKPT_REGS, offsetof(struct thread_struct, ckpt_regs));
-	DEFINE(THREAD_TRANSACT_VR0, offsetof(struct thread_struct,
-					 transact_vr[0]));
-	DEFINE(THREAD_TRANSACT_VSCR, offsetof(struct thread_struct,
-					  transact_vscr));
+	DEFINE(THREAD_TRANSACT_VRSTATE, offsetof(struct thread_struct,
+						 transact_vr));
 	DEFINE(THREAD_TRANSACT_VRSAVE, offsetof(struct thread_struct,
 					    transact_vrsave));
-	DEFINE(THREAD_TRANSACT_FPR0, offsetof(struct thread_struct,
-					  transact_fpr[0]));
-	DEFINE(THREAD_TRANSACT_FPSCR, offsetof(struct thread_struct,
-					   transact_fpscr));
-#ifdef CONFIG_VSX
-	DEFINE(THREAD_TRANSACT_VSR0, offsetof(struct thread_struct,
-					  transact_fpr[0]));
-#endif
+	DEFINE(THREAD_TRANSACT_FPSTATE, offsetof(struct thread_struct,
+						 transact_fp));
 	/* Local pt_regs on stack for Transactional Memory funcs. */
 	DEFINE(TM_FRAME_SIZE, STACK_FRAME_OVERHEAD +
 	       sizeof(struct pt_regs) + 16);