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-rw-r--r--arch/powerpc/kernel/static_call.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/static_call.c b/arch/powerpc/kernel/static_call.c
new file mode 100644
index 0000000000..863a7aa246
--- /dev/null
+++ b/arch/powerpc/kernel/static_call.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/memory.h>
+#include <linux/static_call.h>
+
+#include <asm/code-patching.h>
+
+void arch_static_call_transform(void *site, void *tramp, void *func, bool tail)
+{
+ int err;
+ bool is_ret0 = (func == __static_call_return0);
+ unsigned long target = (unsigned long)(is_ret0 ? tramp + PPC_SCT_RET0 : func);
+ bool is_short = is_offset_in_branch_range((long)target - (long)tramp);
+
+ if (!tramp)
+ return;
+
+ mutex_lock(&text_mutex);
+
+ if (func && !is_short) {
+ err = patch_instruction(tramp + PPC_SCT_DATA, ppc_inst(target));
+ if (err)
+ goto out;
+ }
+
+ if (!func)
+ err = patch_instruction(tramp, ppc_inst(PPC_RAW_BLR()));
+ else if (is_short)
+ err = patch_branch(tramp, target, 0);
+ else
+ err = patch_instruction(tramp, ppc_inst(PPC_RAW_NOP()));
+out:
+ mutex_unlock(&text_mutex);
+
+ if (err)
+ panic("%s: patching failed %pS at %pS\n", __func__, func, tramp);
+}
+EXPORT_SYMBOL_GPL(arch_static_call_transform);