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, 4 insertions, 7 deletions

diff --git a/arch/powerpc/kernel/ptrace32.c b/arch/powerpc/kernel/ptrace32.c
index f51599e941c7..097f8dc426a0 100644
--- a/arch/powerpc/kernel/ptrace32.c
+++ b/arch/powerpc/kernel/ptrace32.c
@@ -43,7 +43,6 @@
 #define FPRNUMBER(i) (((i) - PT_FPR0) >> 1)
 #define FPRHALF(i) (((i) - PT_FPR0) & 1)
 #define FPRINDEX(i) TS_FPRWIDTH * FPRNUMBER(i) * 2 + FPRHALF(i)
-#define FPRINDEX_3264(i) (TS_FPRWIDTH * ((i) - PT_FPR0))
 
 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 			compat_ulong_t caddr, compat_ulong_t cdata)
@@ -105,7 +104,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 			 * to be an array of unsigned int (32 bits) - the
 			 * index passed in is based on this assumption.
 			 */
-			tmp = ((unsigned int *)child->thread.fpr)
+			tmp = ((unsigned int *)child->thread.fp_state.fpr)
 				[FPRINDEX(index)];
 		}
 		ret = put_user((unsigned int)tmp, (u32 __user *)data);
@@ -147,8 +146,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 		if (numReg >= PT_FPR0) {
 			flush_fp_to_thread(child);
 			/* get 64 bit FPR */
-			tmp = ((u64 *)child->thread.fpr)
-				[FPRINDEX_3264(numReg)];
+			tmp = child->thread.fp_state.fpr[numReg - PT_FPR0][0];
 		} else { /* register within PT_REGS struct */
 			unsigned long tmp2;
 			ret = ptrace_get_reg(child, numReg, &tmp2);
@@ -207,7 +205,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 			 * to be an array of unsigned int (32 bits) - the
 			 * index passed in is based on this assumption.
 			 */
-			((unsigned int *)child->thread.fpr)
+			((unsigned int *)child->thread.fp_state.fpr)
 				[FPRINDEX(index)] = data;
 			ret = 0;
 		}
@@ -251,8 +249,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 			u64 *tmp;
 			flush_fp_to_thread(child);
 			/* get 64 bit FPR ... */
-			tmp = &(((u64 *)child->thread.fpr)
-				[FPRINDEX_3264(numReg)]);
+			tmp = &child->thread.fp_state.fpr[numReg - PT_FPR0][0];
 			/* ... write the 32 bit part we want */
 			((u32 *)tmp)[index % 2] = data;
 			ret = 0;