LoongArch: ptrace: Expose hardware breakpoints to debuggers

Implement the regset-based ptrace interface that exposes hardware
breakpoints to user-space debuggers to query and set instruction and
data breakpoints.

Signed-off-by: Qing Zhang <[email protected]>
Signed-off-by: Huacai Chen <[email protected]>

Author: zhangqingmy

arch/loongarch/include/uapi/asm/ptrace.h

@@ -46,6 +46,15 @@ struct user_fp_state {
 	uint32_t    fcsr;
 };
 
+struct user_watch_state {
+	uint16_t dbg_info;
+	struct {
+		uint64_t    addr;
+		uint64_t    mask;
+		uint32_t    ctrl;
+	} dbg_regs[8];
+};
+
 #define PTRACE_SYSEMU			0x1f
 #define PTRACE_SYSEMU_SINGLESTEP	0x20