KVM: arm64: Move hyp_symbol_addr() to kvm_asm.h

Recent refactoring of the arm64 code make it awkward to have
hyp_symbol_addr() in kvm_mmu.h. Instead, move it next to its
main user, which is __hyp_this_cpu_ptr().

Signed-off-by: Marc Zyngier <maz@kernel.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index d9b7da15dbca..352aaebf4198 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -82,6 +82,26 @@ extern u32 __kvm_get_mdcr_el2(void);
 extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ];
 
 /*
+ * Obtain the PC-relative address of a kernel symbol
+ * s: symbol
+ *
+ * The goal of this macro is to return a symbol's address based on a
+ * PC-relative computation, as opposed to a loading the VA from a
+ * constant pool or something similar. This works well for HYP, as an
+ * absolute VA is guaranteed to be wrong. Only use this if trying to
+ * obtain the address of a symbol (i.e. not something you obtained by
+ * following a pointer).
+ */
+#define hyp_symbol_addr(s)						\
+	({								\
+		typeof(s) *addr;					\
+		asm("adrp	%0, %1\n"				\
+		    "add	%0, %0, :lo12:%1\n"			\
+		    : "=r" (addr) : "S" (&s));				\
+		addr;							\
+	})
+
+/*
  * Home-grown __this_cpu_{ptr,read} variants that always work at HYP,
  * provided that sym is really a *symbol* and not a pointer obtained from
  * a data structure. As for SHIFT_PERCPU_PTR(), the creative casting keeps