arm64: stacktrace: remove stack type from fp translator

In subsequent patches we'll remove the stack_type enum, and move the FP
translation logic out of the raw FP unwind code.

In preparation for doing so, this patch removes the type parameter from
the FP translation callback, and modifies kvm_nvhe_stack_kern_va() to
determine the relevant stack directly.

So that kvm_nvhe_stack_kern_va() can use the stackinfo_*() helpers,
these are moved earlier in the file, but are not modified in any way.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <[e-mail]>
Reviewed-by: Kalesh Singh <[e-mail]>
Reviewed-by: Madhavan T. Venkataraman <[e-mail]>
Reviewed-by: Mark Brown <[e-mail]>
Cc: Fuad Tabba <[e-mail]>
Cc: Marc Zyngier <[e-mail]>
Cc: Will Deacon <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Catalin Marinas <[e-mail]>

arch/arm64/include/asm/stacktrace/common.h

···
  * pointer to a kernel address.
  *
  * @fp:   the frame pointer to be updated to its kernel address.
- * @type: the stack type associated with frame pointer @fp
  *
  * Return: true if the VA can be translated, false otherwise.
  *
  * Upon success @fp is updated to the corresponding kernel virtual address.
  */
-typedef bool (*stack_trace_translate_fp_fn)(unsigned long *fp,
-					    enum stack_type type);
+typedef bool (*stack_trace_translate_fp_fn)(unsigned long *fp);
 
 /**
  * typedef on_accessible_stack_fn() - Check whether a stack range is on any of
···
 	 * If fp is not from the current address space perform the necessary
 	 * translation before dereferencing it to get the next fp.
 	 */
-	if (translate_fp && !translate_fp(&kern_fp, info.type))
+	if (translate_fp && !translate_fp(&kern_fp))
 		return -EINVAL;
 
 	/*

arch/arm64/kvm/stacktrace.c

···
 
 #include <asm/stacktrace/nvhe.h>
 
-/*
- * kvm_nvhe_stack_kern_va - Convert KVM nVHE HYP stack addresses to a kernel VAs
- *
- * The nVHE hypervisor stack is mapped in the flexible 'private' VA range, to
- * allow for guard pages below the stack. Consequently, the fixed offset address
- * translation macros won't work here.
- *
- * The kernel VA is calculated as an offset from the kernel VA of the hypervisor
- * stack base.
- *
- * Returns true on success and updates @addr to its corresponding kernel VA;
- * otherwise returns false.
- */
-static bool kvm_nvhe_stack_kern_va(unsigned long *addr,
-				   enum stack_type type)
-{
-	struct kvm_nvhe_stacktrace_info *stacktrace_info;
-	unsigned long hyp_base, kern_base, hyp_offset;
-
-	stacktrace_info = this_cpu_ptr_nvhe_sym(kvm_stacktrace_info);
-
-	switch (type) {
-	case STACK_TYPE_HYP:
-		kern_base = (unsigned long)*this_cpu_ptr(&kvm_arm_hyp_stack_page);
-		hyp_base = (unsigned long)stacktrace_info->stack_base;
-		break;
-	case STACK_TYPE_OVERFLOW:
-		kern_base = (unsigned long)this_cpu_ptr_nvhe_sym(overflow_stack);
-		hyp_base = (unsigned long)stacktrace_info->overflow_stack_base;
-		break;
-	default:
-		return false;
-	}
-
-	hyp_offset = *addr - hyp_base;
-
-	*addr = kern_base + hyp_offset;
-
-	return true;
-}
-
 static struct stack_info stackinfo_get_overflow(void)
 {
 	struct kvm_nvhe_stacktrace_info *stacktrace_info
···
 	};
 }
 
+/*
+ * kvm_nvhe_stack_kern_va - Convert KVM nVHE HYP stack addresses to a kernel VAs
+ *
+ * The nVHE hypervisor stack is mapped in the flexible 'private' VA range, to
+ * allow for guard pages below the stack. Consequently, the fixed offset address
+ * translation macros won't work here.
+ *
+ * The kernel VA is calculated as an offset from the kernel VA of the hypervisor
+ * stack base.
+ *
+ * Returns true on success and updates @addr to its corresponding kernel VA;
+ * otherwise returns false.
+ */
+static bool kvm_nvhe_stack_kern_va(unsigned long *addr, unsigned long size)
+{
+	struct kvm_nvhe_stacktrace_info *stacktrace_info;
+	unsigned long hyp_base, kern_base, hyp_offset;
+	struct stack_info stack;
+
+	stacktrace_info = this_cpu_ptr_nvhe_sym(kvm_stacktrace_info);
+
+	stack = stackinfo_get_hyp();
+	if (stackinfo_on_stack(&stack, *addr, size)) {
+		kern_base = (unsigned long)*this_cpu_ptr(&kvm_arm_hyp_stack_page);
+		hyp_base = (unsigned long)stacktrace_info->stack_base;
+		goto found;
+	}
+
+	stack = stackinfo_get_overflow();
+	if (stackinfo_on_stack(&stack, *addr, size)) {
+		kern_base = (unsigned long)this_cpu_ptr_nvhe_sym(overflow_stack);
+		hyp_base = (unsigned long)stacktrace_info->overflow_stack_base;
+		goto found;
+	}
+
+	return false;
+
+found:
+	hyp_offset = *addr - hyp_base;
+
+	*addr = kern_base + hyp_offset;
+
+	return true;
+}
+
+/*
+ * Convert a KVN nVHE HYP frame record address to a kernel VA
+ */
+static bool kvm_nvhe_stack_kern_record_va(unsigned long *addr)
+{
+	return kvm_nvhe_stack_kern_va(addr, 16);
+}
+
 static bool on_accessible_stack(const struct task_struct *tsk,
 				unsigned long sp, unsigned long size,
 				struct stack_info *info)
···
 static int unwind_next(struct unwind_state *state)
 {
 	return unwind_next_frame_record(state, on_accessible_stack,
-					kvm_nvhe_stack_kern_va);
+					kvm_nvhe_stack_kern_record_va);
 }
 
 static void unwind(struct unwind_state *state,