arm64: expand register mapping between AArch32 and AArch64

The general purpose registers in AArch32 are mapped in an
architecturally defined manner into the AArch64 registers.

It allows the AArch32 registers of an application or a virtual
machine to be inspected by the OS or an hypervisor.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index b04d340..de68a5a 100644 (file)
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -44,10 +44,27 @@
 
 /* sizeof(struct user) for AArch32 */
 #define COMPAT_USER_SZ 296
-/* AArch32 uses x13 as the stack pointer... */
+
+/* Architecturally defined mapping between AArch32 and AArch64 registers */
+#define compat_usr(x)  regs[(x)]
 #define compat_sp      regs[13]
-/* ... and x14 as the link register. */
 #define compat_lr      regs[14]
+#define compat_sp_hyp  regs[15]
+#define compat_sp_irq  regs[16]
+#define compat_lr_irq  regs[17]
+#define compat_sp_svc  regs[18]
+#define compat_lr_svc  regs[19]
+#define compat_sp_abt  regs[20]
+#define compat_lr_abt  regs[21]
+#define compat_sp_und  regs[22]
+#define compat_lr_und  regs[23]
+#define compat_r8_fiq  regs[24]
+#define compat_r9_fiq  regs[25]
+#define compat_r10_fiq regs[26]
+#define compat_r11_fiq regs[27]
+#define compat_r12_fiq regs[28]
+#define compat_sp_fiq  regs[29]
+#define compat_lr_fiq  regs[30]
 
 /*
  * This struct defines the way the registers are stored on the stack during an