efi: Move efi_mem_type() to common code

This follows efi_mem_attributes(), as it's similarly generic. Drop
__weak from that one though (and don't introduce it for efi_mem_type()
in the first place) to make clear that other overrides to these
functions are really not intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-5-ard.biesheuvel@linaro.org
[ Resolved conflict with: f99afd08a4: (efi: Update efi_mem_type() to return an error rather than 0) ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

drivers/firmware/efi/efi.c

@@ -810,6 +810,11 @@ char * __init efi_md_typeattr_format(char *buf, size_t size,
 	return buf;
 }
 
+/*
+ * IA64 has a funky EFI memory map that doesn't work the same way as
+ * other architectures.
+ */
+#ifndef CONFIG_IA64
 /*
  * efi_mem_attributes - lookup memmap attributes for physical address
  * @phys_addr: the physical address to lookup
@@ -817,13 +822,8 @@ char * __init efi_md_typeattr_format(char *buf, size_t size,
  * Search in the EFI memory map for the region covering
  * @phys_addr. Returns the EFI memory attributes if the region
  * was found in the memory map, 0 otherwise.
- *
- * Despite being marked __weak, most architectures should *not*
- * override this function. It is __weak solely for the benefit
- * of ia64 which has a funky EFI memory map that doesn't work
- * the same way as other architectures.
  */
-u64 __weak efi_mem_attributes(unsigned long phys_addr)
+u64 efi_mem_attributes(unsigned long phys_addr)
 {
 	efi_memory_desc_t *md;
 
@@ -839,6 +839,31 @@ u64 __weak efi_mem_attributes(unsigned long phys_addr)
 	return 0;
 }
 
+/*
+ * efi_mem_type - lookup memmap type for physical address
+ * @phys_addr: the physical address to lookup
+ *
+ * Search in the EFI memory map for the region covering @phys_addr.
+ * Returns the EFI memory type if the region was found in the memory
+ * map, EFI_RESERVED_TYPE (zero) otherwise.
+ */
+int efi_mem_type(unsigned long phys_addr)
+{
+	const efi_memory_desc_t *md;
+
+	if (!efi_enabled(EFI_MEMMAP))
+		return -ENOTSUPP;
+
+	for_each_efi_memory_desc(md) {
+		if ((md->phys_addr <= phys_addr) &&
+		    (phys_addr < (md->phys_addr +
+				  (md->num_pages << EFI_PAGE_SHIFT))))
+			return md->type;
+	}
+	return -EINVAL;
+}
+#endif
+
 int efi_status_to_err(efi_status_t status)
 {
 	int err;