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Diffstat (limited to 'arch/x86/include/asm/jump_label.h')
-rw-r--r--arch/x86/include/asm/jump_label.h69
1 files changed, 69 insertions, 0 deletions
diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h
new file mode 100644
index 000000000..071572e23
--- /dev/null
+++ b/arch/x86/include/asm/jump_label.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_JUMP_LABEL_H
+#define _ASM_X86_JUMP_LABEL_H
+
+#define HAVE_JUMP_LABEL_BATCH
+
+#include <asm/asm.h>
+#include <asm/nops.h>
+
+#ifndef __ASSEMBLY__
+
+#include <linux/stringify.h>
+#include <linux/types.h>
+
+#define JUMP_TABLE_ENTRY \
+ ".pushsection __jump_table, \"aw\" \n\t" \
+ _ASM_ALIGN "\n\t" \
+ ".long 1b - . \n\t" \
+ ".long %l[l_yes] - . \n\t" \
+ _ASM_PTR "%c0 + %c1 - .\n\t" \
+ ".popsection \n\t"
+
+#ifdef CONFIG_HAVE_JUMP_LABEL_HACK
+
+static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
+{
+ asm_volatile_goto("1:"
+ "jmp %l[l_yes] # objtool NOPs this \n\t"
+ JUMP_TABLE_ENTRY
+ : : "i" (key), "i" (2 | branch) : : l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
+#else /* !CONFIG_HAVE_JUMP_LABEL_HACK */
+
+static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch)
+{
+ asm_volatile_goto("1:"
+ ".byte " __stringify(BYTES_NOP5) "\n\t"
+ JUMP_TABLE_ENTRY
+ : : "i" (key), "i" (branch) : : l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
+#endif /* CONFIG_HAVE_JUMP_LABEL_HACK */
+
+static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch)
+{
+ asm_volatile_goto("1:"
+ "jmp %l[l_yes]\n\t"
+ JUMP_TABLE_ENTRY
+ : : "i" (key), "i" (branch) : : l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
+extern int arch_jump_entry_size(struct jump_entry *entry);
+
+#endif /* __ASSEMBLY__ */
+
+#endif