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// 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);
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