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// SPDX-License-Identifier: GPL-2.0#include <linux/memory.h>#include <linux/static_call.h> #include <asm/text-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 _tramp = (unsigned long)tramp;	unsigned long _func = (unsigned long)func;	unsigned long _ret0 = _tramp + PPC_SCT_RET0;	bool is_short = is_offset_in_branch_range((long)func - (long)(site ? : tramp)); 	mutex_lock(&text_mutex); 	if (site && tail) {		if (!func)			err = patch_instruction(site, ppc_inst(PPC_RAW_BLR()));		else if (is_ret0)			err = patch_branch(site, _ret0, 0);		else if (is_short)			err = patch_branch(site, _func, 0);		else if (tramp)			err = patch_branch(site, _tramp, 0);		else			err = 0;	} else if (site) {		if (!func)			err = patch_instruction(site, ppc_inst(PPC_RAW_NOP()));		else if (is_ret0)			err = patch_instruction(site, ppc_inst(PPC_RAW_LI(_R3, 0)));		else if (is_short)			err = patch_branch(site, _func, BRANCH_SET_LINK);		else if (tramp)			err = patch_branch(site, _tramp, BRANCH_SET_LINK);		else			err = 0;	} else if (tramp) {		if (func && !is_short) {			err = patch_ulong(tramp + PPC_SCT_DATA, _func);			if (err)				goto out;		} 		if (!func)			err = patch_instruction(tramp, ppc_inst(PPC_RAW_BLR()));		else if (is_ret0)			err = patch_branch(tramp, _ret0, 0);		else if (is_short)			err = patch_branch(tramp, _func, 0);		else			err = patch_instruction(tramp, ppc_inst(PPC_RAW_NOP()));	} else {		err = 0;	} 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);