efi/arm64: Move EFI runtime call setup/teardown helpers out of line

Only the arch_efi_call_virt() macro that some architectures override
needs to be a macro, given that it is variadic and encapsulates calls
via function pointers that have different prototypes.

The associated setup and teardown code are not special in this regard,
and don't need to be instantiated at each call site. So turn them into
ordinary C functions and move them out of line.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Author: ardbiesheuvel

arch/arm64/include/asm/efi.h

@@ -30,28 +30,16 @@ int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
 int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md,
 				bool has_bti);
 
-#define arch_efi_call_virt_setup()					\
-({									\
-	efi_virtmap_load();						\
-	__efi_fpsimd_begin();						\
-	raw_spin_lock(&efi_rt_lock);					\
-})
-
 #undef arch_efi_call_virt
 #define arch_efi_call_virt(p, f, args...)				\
 	__efi_rt_asm_wrapper((p)->f, #f, args)
 
-#define arch_efi_call_virt_teardown()					\
-({									\
-	raw_spin_unlock(&efi_rt_lock);					\
-	__efi_fpsimd_end();						\
-	efi_virtmap_unload();						\
-})
-
-extern raw_spinlock_t efi_rt_lock;
 extern u64 *efi_rt_stack_top;
 efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...);
 
+void arch_efi_call_virt_setup(void);
+void arch_efi_call_virt_teardown(void);
+
 /*
  * efi_rt_stack_top[-1] contains the value the stack pointer had before
  * switching to the EFI runtime stack.

arch/arm64/kernel/efi.c

@@ -158,7 +158,21 @@ asmlinkage efi_status_t efi_handle_corrupted_x18(efi_status_t s, const char *f)
 	return s;
 }
 
-DEFINE_RAW_SPINLOCK(efi_rt_lock);
+static DEFINE_RAW_SPINLOCK(efi_rt_lock);
+
+void arch_efi_call_virt_setup(void)
+{
+	efi_virtmap_load();
+	__efi_fpsimd_begin();
+	raw_spin_lock(&efi_rt_lock);
+}
+
+void arch_efi_call_virt_teardown(void)
+{
+	raw_spin_unlock(&efi_rt_lock);
+	__efi_fpsimd_end();
+	efi_virtmap_unload();
+}
 
 asmlinkage u64 *efi_rt_stack_top __ro_after_init;