Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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);