s390/jump_label: Switch to relative references

Enable support for relative references in jump_label entries.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jessica Yu <jeyu@kernel.org>
Link: https://lkml.kernel.org/r/20180919065144.25010-10-ard.biesheuvel@linaro.org

1 files changed, 16 insertions, 24 deletions

diff --git a/arch/s390/include/asm/jump_label.h b/arch/s390/include/asm/jump_label.h
index 40f651292aa7..e2d3e6c43395 100644
--- a/arch/s390/include/asm/jump_label.h
+++ b/arch/s390/include/asm/jump_label.h
@@ -14,41 +14,33 @@
  * We use a brcl 0,2 instruction for jump labels at compile time so it
  * can be easily distinguished from a hotpatch generated instruction.
  */
-static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
+static inline bool arch_static_branch(struct static_key *key, bool branch)
 {
-	asm_volatile_goto("0:	brcl 0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n"
-		".pushsection __jump_table, \"aw\"\n"
-		".balign 8\n"
-		".quad 0b, %l[label], %0\n"
-		".popsection\n"
-		: : "X" (&((char *)key)[branch]) : : label);
-
+	asm_volatile_goto("0:	brcl	0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n"
+			  ".pushsection __jump_table,\"aw\"\n"
+			  ".balign	8\n"
+			  ".long	0b-.,%l[label]-.\n"
+			  ".quad	%0-.\n"
+			  ".popsection\n"
+			  : : "X" (&((char *)key)[branch]) : : label);
 	return false;
 label:
 	return true;
 }
 
-static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
+static inline bool arch_static_branch_jump(struct static_key *key, bool branch)
 {
-	asm_volatile_goto("0:	brcl 15, %l[label]\n"
-		".pushsection __jump_table, \"aw\"\n"
-		".balign 8\n"
-		".quad 0b, %l[label], %0\n"
-		".popsection\n"
-		: : "X" (&((char *)key)[branch]) : : label);
-
+	asm_volatile_goto("0:	brcl 15,%l[label]\n"
+			  ".pushsection __jump_table,\"aw\"\n"
+			  ".balign	8\n"
+			  ".long	0b-.,%l[label]-.\n"
+			  ".quad	%0-.\n"
+			  ".popsection\n"
+			  : : "X" (&((char *)key)[branch]) : : label);
 	return false;
 label:
 	return true;
 }
 
-typedef unsigned long jump_label_t;
-
-struct jump_entry {
-	jump_label_t code;
-	jump_label_t target;
-	jump_label_t key;
-};
-
 #endif  /* __ASSEMBLY__ */
 #endif