diff options
Diffstat (limited to 'arch/powerpc/kernel/static_call.c')
| -rw-r--r-- | arch/powerpc/kernel/static_call.c | 37 |
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 000000000000..863a7aa24650 --- /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); |