arch/s390/lib/uaccess.c - pub/scm/linux/kernel/git/next/linux-next - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  *  Standard user space access functions based on mvcp/mvcs and doing
  *  interesting things in the secondary space mode.
  *
  *    Copyright IBM Corp. 2006,2014
  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
  *		 Gerald Schaefer (gerald.schaefer@de.ibm.com)
  */

 #include <linux/kprobes.h>
 #include <linux/uaccess.h>
 #include <linux/export.h>
 #include <linux/mm.h>
 #include <asm/asm-extable.h>
 #include <asm/ctlreg.h>
 #include <asm/skey.h>

 #ifdef CONFIG_DEBUG_ENTRY
 void debug_user_asce(int exit)
 {
 	struct lowcore *lc = get_lowcore();
 	struct ctlreg cr1, cr7;

 	local_ctl_store(1, &cr1);
 	local_ctl_store(7, &cr7);
 	if (cr1.val == lc->user_asce.val && cr7.val == lc->user_asce.val)
 		return;
 	panic("incorrect ASCE on kernel %s\n"
 	      "cr1:    %016lx cr7:  %016lx\n"
 	      "kernel: %016lx user: %016lx\n",
 	      exit ? "exit" : "entry", cr1.val, cr7.val,
 	      lc->kernel_asce.val, lc->user_asce.val);
 }
 #endif /*CONFIG_DEBUG_ENTRY */

 union oac {
 	unsigned int val;
 	struct {
 		struct {
 			unsigned short key : 4;
 			unsigned short	   : 4;
 			unsigned short as  : 2;
 			unsigned short	   : 4;
 			unsigned short k   : 1;
 			unsigned short a   : 1;
 		} oac1;
 		struct {
 			unsigned short key : 4;
 			unsigned short	   : 4;
 			unsigned short as  : 2;
 			unsigned short	   : 4;
 			unsigned short k   : 1;
 			unsigned short a   : 1;
 		} oac2;
 	};
 };

 static uaccess_kmsan_or_inline __must_check unsigned long
 raw_copy_from_user_key(void *to, const void __user *from, unsigned long size, unsigned long key)
 {
 	unsigned long osize;
 	union oac spec = {
 		.oac2.key = key,
 		.oac2.as = PSW_BITS_AS_SECONDARY,
 		.oac2.k = 1,
 		.oac2.a = 1,
 	};
 	int cc;

 	while (1) {
 		osize = size;
 		asm_inline volatile(
 			"	lr	%%r0,%[spec]\n"
 			"0:	mvcos	%[to],%[from],%[size]\n"
 			"1:	nopr	%%r7\n"
 			CC_IPM(cc)
 			EX_TABLE_UA_MVCOS_FROM(0b, 0b)
 			EX_TABLE_UA_MVCOS_FROM(1b, 0b)
 			: CC_OUT(cc, cc), [size] "+d" (size), [to] "=Q" (*(char *)to)
 			: [spec] "d" (spec.val), [from] "Q" (*(const char __user *)from)
 			: CC_CLOBBER_LIST("memory", "0"));
 		if (CC_TRANSFORM(cc) == 0)
 			return osize - size;
 		size -= 4096;
 		to += 4096;
 		from += 4096;
 	}
 }

 unsigned long _copy_from_user_key(void *to, const void __user *from,
 				  unsigned long n, unsigned long key)
 {
 	unsigned long res = n;

 	might_fault();
 	if (!should_fail_usercopy()) {
 		instrument_copy_from_user_before(to, from, n);
 		res = raw_copy_from_user_key(to, from, n, key);
 		instrument_copy_from_user_after(to, from, n, res);
 	}
 	if (unlikely(res))
 		memset(to + (n - res), 0, res);
 	return res;
 }
 EXPORT_SYMBOL(_copy_from_user_key);

 static uaccess_kmsan_or_inline __must_check unsigned long
 raw_copy_to_user_key(void __user *to, const void *from, unsigned long size, unsigned long key)
 {
 	unsigned long osize;
 	union oac spec = {
 		.oac1.key = key,
 		.oac1.as = PSW_BITS_AS_SECONDARY,
 		.oac1.k = 1,
 		.oac1.a = 1,
 	};
 	int cc;

 	while (1) {
 		osize = size;
 		asm_inline volatile(
 			"	lr	%%r0,%[spec]\n"
 			"0:	mvcos	%[to],%[from],%[size]\n"
 			"1:	nopr	%%r7\n"
 			CC_IPM(cc)
 			EX_TABLE_UA_MVCOS_TO(0b, 0b)
 			EX_TABLE_UA_MVCOS_TO(1b, 0b)
 			: CC_OUT(cc, cc), [size] "+d" (size), [to] "=Q" (*(char __user *)to)
 			: [spec] "d" (spec.val), [from] "Q" (*(const char *)from)
 			: CC_CLOBBER_LIST("memory", "0"));
 		if (CC_TRANSFORM(cc) == 0)
 			return osize - size;
 		size -= 4096;
 		to += 4096;
 		from += 4096;
 	}
 }

 unsigned long _copy_to_user_key(void __user *to, const void *from,
 				unsigned long n, unsigned long key)
 {
 	might_fault();
 	if (should_fail_usercopy())
 		return n;
 	instrument_copy_to_user(to, from, n);
 	return raw_copy_to_user_key(to, from, n, key);
 }
 EXPORT_SYMBOL(_copy_to_user_key);

 #define CMPXCHG_USER_KEY_MAX_LOOPS 128

 static nokprobe_inline int __cmpxchg_user_key_small(unsigned long address, unsigned int *uval,
 						    unsigned int old, unsigned int new,
 						    unsigned int mask, unsigned long key)
 {
 	unsigned long count;
 	unsigned int prev;
 	bool sacf_flag;
 	int rc = 0;

 	skey_regions_initialize();
 	sacf_flag = enable_sacf_uaccess();
 	asm_inline volatile(
 		"20:	spka	0(%[key])\n"
 		"	sacf	256\n"
 		"	llill	%[count],%[max_loops]\n"
 		"0:	l	%[prev],%[address]\n"
 		"1:	nr	%[prev],%[mask]\n"
 		"	xilf	%[mask],0xffffffff\n"
 		"	or	%[new],%[prev]\n"
 		"	or	%[prev],%[tmp]\n"
 		"2:	lr	%[tmp],%[prev]\n"
 		"3:	cs	%[prev],%[new],%[address]\n"
 		"4:	jnl	5f\n"
 		"	xr	%[tmp],%[prev]\n"
 		"	xr	%[new],%[tmp]\n"
 		"	nr	%[tmp],%[mask]\n"
 		"	jnz	5f\n"
 		"	brct	%[count],2b\n"
 		"5:	sacf	768\n"
 		"	spka	%[default_key]\n"
 		"21:\n"
 		EX_TABLE_UA_LOAD_REG(0b, 5b, %[rc], %[prev])
 		EX_TABLE_UA_LOAD_REG(1b, 5b, %[rc], %[prev])
 		EX_TABLE_UA_LOAD_REG(3b, 5b, %[rc], %[prev])
 		EX_TABLE_UA_LOAD_REG(4b, 5b, %[rc], %[prev])
 		SKEY_REGION(20b, 21b)
 		: [rc] "+&d" (rc),
 		[prev] "=&d" (prev),
 		[address] "+Q" (*(int *)address),
 		[tmp] "+&d" (old),
 		[new] "+&d" (new),
 		[mask] "+&d" (mask),
 		[count] "=a" (count)
 		: [key] "%[count]" (key << 4),
 		[default_key] "J" (PAGE_DEFAULT_KEY),
 		[max_loops] "J" (CMPXCHG_USER_KEY_MAX_LOOPS)
 		: "memory", "cc");
 	disable_sacf_uaccess(sacf_flag);
 	*uval = prev;
 	if (!count)
 		rc = -EAGAIN;
 	return rc;
 }

 int __kprobes __cmpxchg_user_key1(unsigned long address, unsigned char *uval,
 				  unsigned char old, unsigned char new, unsigned long key)
 {
 	unsigned int prev, shift, mask, _old, _new;
 	int rc;

 	shift = (3 ^ (address & 3)) << 3;
 	address ^= address & 3;
 	_old = (unsigned int)old << shift;
 	_new = (unsigned int)new << shift;
 	mask = ~(0xff << shift);
 	rc = __cmpxchg_user_key_small(address, &prev, _old, _new, mask, key);
 	*uval = prev >> shift;
 	return rc;
 }
 EXPORT_SYMBOL(__cmpxchg_user_key1);

 int __kprobes __cmpxchg_user_key2(unsigned long address, unsigned short *uval,
 				  unsigned short old, unsigned short new, unsigned long key)
 {
 	unsigned int prev, shift, mask, _old, _new;
 	int rc;

 	shift = (2 ^ (address & 2)) << 3;
 	address ^= address & 2;
 	_old = (unsigned int)old << shift;
 	_new = (unsigned int)new << shift;
 	mask = ~(0xffff << shift);
 	rc = __cmpxchg_user_key_small(address, &prev, _old, _new, mask, key);
 	*uval = prev >> shift;
 	return rc;
 }
 EXPORT_SYMBOL(__cmpxchg_user_key2);

 int __kprobes __cmpxchg_user_key4(unsigned long address, unsigned int *uval,
 				  unsigned int old, unsigned int new, unsigned long key)
 {
 	unsigned int prev = old;
 	bool sacf_flag;
 	int rc = 0;

 	skey_regions_initialize();
 	sacf_flag = enable_sacf_uaccess();
 	asm_inline volatile(
 		"20:	spka	0(%[key])\n"
 		"	sacf	256\n"
 		"0:	cs	%[prev],%[new],%[address]\n"
 		"1:	sacf	768\n"
 		"	spka	%[default_key]\n"
 		"21:\n"
 		EX_TABLE_UA_LOAD_REG(0b, 1b, %[rc], %[prev])
 		EX_TABLE_UA_LOAD_REG(1b, 1b, %[rc], %[prev])
 		SKEY_REGION(20b, 21b)
 		: [rc] "+&d" (rc),
 		[prev] "+&d" (prev),
 		[address] "+Q" (*(int *)address)
 		: [new] "d" (new),
 		[key] "a" (key << 4),
 		[default_key] "J" (PAGE_DEFAULT_KEY)
 		: "memory", "cc");
 	disable_sacf_uaccess(sacf_flag);
 	*uval = prev;
 	return rc;
 }
 EXPORT_SYMBOL(__cmpxchg_user_key4);

 int __kprobes __cmpxchg_user_key8(unsigned long address, unsigned long *uval,
 				  unsigned long old, unsigned long new, unsigned long key)
 {
 	unsigned long prev = old;
 	bool sacf_flag;
 	int rc = 0;

 	skey_regions_initialize();
 	sacf_flag = enable_sacf_uaccess();
 	asm_inline volatile(
 		"20:	spka	0(%[key])\n"
 		"	sacf	256\n"
 		"0:	csg	%[prev],%[new],%[address]\n"
 		"1:	sacf	768\n"
 		"	spka	%[default_key]\n"
 		"21:\n"
 		EX_TABLE_UA_LOAD_REG(0b, 1b, %[rc], %[prev])
 		EX_TABLE_UA_LOAD_REG(1b, 1b, %[rc], %[prev])
 		SKEY_REGION(20b, 21b)
 		: [rc] "+&d" (rc),
 		[prev] "+&d" (prev),
 		[address] "+QS" (*(long *)address)
 		: [new] "d" (new),
 		[key] "a" (key << 4),
 		[default_key] "J" (PAGE_DEFAULT_KEY)
 		: "memory", "cc");
 	disable_sacf_uaccess(sacf_flag);
 	*uval = prev;
 	return rc;
 }
 EXPORT_SYMBOL(__cmpxchg_user_key8);

 int __kprobes __cmpxchg_user_key16(unsigned long address, __uint128_t *uval,
 				   __uint128_t old, __uint128_t new, unsigned long key)
 {
 	__uint128_t prev = old;
 	bool sacf_flag;
 	int rc = 0;

 	skey_regions_initialize();
 	sacf_flag = enable_sacf_uaccess();
 	asm_inline volatile(
 		"20:	spka	0(%[key])\n"
 		"	sacf	256\n"
 		"0:	cdsg	%[prev],%[new],%[address]\n"
 		"1:	sacf	768\n"
 		"	spka	%[default_key]\n"
 		"21:\n"
 		EX_TABLE_UA_LOAD_REGPAIR(0b, 1b, %[rc], %[prev])
 		EX_TABLE_UA_LOAD_REGPAIR(1b, 1b, %[rc], %[prev])
 		SKEY_REGION(20b, 21b)
 		: [rc] "+&d" (rc),
 		[prev] "+&d" (prev),
 		[address] "+QS" (*(__int128_t *)address)
 		: [new] "d" (new),
 		[key] "a" (key << 4),
 		[default_key] "J" (PAGE_DEFAULT_KEY)
 		: "memory", "cc");
 	disable_sacf_uaccess(sacf_flag);
 	*uval = prev;
 	return rc;
 }
 EXPORT_SYMBOL(__cmpxchg_user_key16);
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Standard user space access functions based on mvcp/mvcs and doing
	* interesting things in the secondary space mode.
	*
	* Copyright IBM Corp. 2006,2014
	* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
	* Gerald Schaefer (gerald.schaefer@de.ibm.com)
	*/

	#include <linux/kprobes.h>
	#include <linux/uaccess.h>
	#include <linux/export.h>
	#include <linux/mm.h>
	#include <asm/asm-extable.h>
	#include <asm/ctlreg.h>
	#include <asm/skey.h>

	#ifdef CONFIG_DEBUG_ENTRY
	void debug_user_asce(int exit)
	{
	struct lowcore *lc = get_lowcore();
	struct ctlreg cr1, cr7;

	local_ctl_store(1, &cr1);
	local_ctl_store(7, &cr7);
	if (cr1.val == lc->user_asce.val && cr7.val == lc->user_asce.val)
	return;
	panic("incorrect ASCE on kernel %s\n"
	"cr1: %016lx cr7: %016lx\n"
	"kernel: %016lx user: %016lx\n",
	exit ? "exit" : "entry", cr1.val, cr7.val,
	lc->kernel_asce.val, lc->user_asce.val);
	}
	#endif /CONFIG_DEBUG_ENTRY /

	union oac {
	unsigned int val;
	struct {
	struct {
	unsigned short key : 4;
	unsigned short : 4;
	unsigned short as : 2;
	unsigned short : 4;
	unsigned short k : 1;
	unsigned short a : 1;
	} oac1;
	struct {
	unsigned short key : 4;
	unsigned short : 4;
	unsigned short as : 2;
	unsigned short : 4;
	unsigned short k : 1;
	unsigned short a : 1;
	} oac2;
	};
	};

	static uaccess_kmsan_or_inline __must_check unsigned long
	raw_copy_from_user_key(void to, const void __user from, unsigned long size, unsigned long key)
	{
	unsigned long osize;
	union oac spec = {
	.oac2.key = key,
	.oac2.as = PSW_BITS_AS_SECONDARY,
	.oac2.k = 1,
	.oac2.a = 1,
	};
	int cc;

	while (1) {
	osize = size;
	asm_inline volatile(
	" lr %%r0,%[spec]\n"
	"0: mvcos %[to],%[from],%[size]\n"
	"1: nopr %%r7\n"
	CC_IPM(cc)
	EX_TABLE_UA_MVCOS_FROM(0b, 0b)
	EX_TABLE_UA_MVCOS_FROM(1b, 0b)
	: CC_OUT(cc, cc), [size] "+d" (size), [to] "=Q" ((char )to)
	: [spec] "d" (spec.val), [from] "Q" ((const char __user )from)
	: CC_CLOBBER_LIST("memory", "0"));
	if (CC_TRANSFORM(cc) == 0)
	return osize - size;
	size -= 4096;
	to += 4096;
	from += 4096;
	}
	}

	unsigned long _copy_from_user_key(void to, const void __user from,
	unsigned long n, unsigned long key)
	{
	unsigned long res = n;

	might_fault();
	if (!should_fail_usercopy()) {
	instrument_copy_from_user_before(to, from, n);
	res = raw_copy_from_user_key(to, from, n, key);
	instrument_copy_from_user_after(to, from, n, res);
	}
	if (unlikely(res))
	memset(to + (n - res), 0, res);
	return res;
	}
	EXPORT_SYMBOL(_copy_from_user_key);

	static uaccess_kmsan_or_inline __must_check unsigned long
	raw_copy_to_user_key(void __user to, const void from, unsigned long size, unsigned long key)
	{
	unsigned long osize;
	union oac spec = {
	.oac1.key = key,
	.oac1.as = PSW_BITS_AS_SECONDARY,
	.oac1.k = 1,
	.oac1.a = 1,
	};
	int cc;

	while (1) {
	osize = size;
	asm_inline volatile(
	" lr %%r0,%[spec]\n"
	"0: mvcos %[to],%[from],%[size]\n"
	"1: nopr %%r7\n"
	CC_IPM(cc)
	EX_TABLE_UA_MVCOS_TO(0b, 0b)
	EX_TABLE_UA_MVCOS_TO(1b, 0b)
	: CC_OUT(cc, cc), [size] "+d" (size), [to] "=Q" ((char __user )to)
	: [spec] "d" (spec.val), [from] "Q" ((const char )from)
	: CC_CLOBBER_LIST("memory", "0"));
	if (CC_TRANSFORM(cc) == 0)
	return osize - size;
	size -= 4096;
	to += 4096;
	from += 4096;
	}
	}

	unsigned long _copy_to_user_key(void __user to, const void from,
	unsigned long n, unsigned long key)
	{
	might_fault();
	if (should_fail_usercopy())
	return n;
	instrument_copy_to_user(to, from, n);
	return raw_copy_to_user_key(to, from, n, key);
	}
	EXPORT_SYMBOL(_copy_to_user_key);

	#define CMPXCHG_USER_KEY_MAX_LOOPS 128

	static nokprobe_inline int __cmpxchg_user_key_small(unsigned long address, unsigned int *uval,
	unsigned int old, unsigned int new,
	unsigned int mask, unsigned long key)
	{
	unsigned long count;
	unsigned int prev;
	bool sacf_flag;
	int rc = 0;

	skey_regions_initialize();
	sacf_flag = enable_sacf_uaccess();
	asm_inline volatile(
	"20: spka 0(%[key])\n"
	" sacf 256\n"
	" llill %[count],%[max_loops]\n"
	"0: l %[prev],%[address]\n"
	"1: nr %[prev],%[mask]\n"
	" xilf %[mask],0xffffffff\n"
	" or %[new],%[prev]\n"
	" or %[prev],%[tmp]\n"
	"2: lr %[tmp],%[prev]\n"
	"3: cs %[prev],%[new],%[address]\n"
	"4: jnl 5f\n"
	" xr %[tmp],%[prev]\n"
	" xr %[new],%[tmp]\n"
	" nr %[tmp],%[mask]\n"
	" jnz 5f\n"
	" brct %[count],2b\n"
	"5: sacf 768\n"
	" spka %[default_key]\n"
	"21:\n"
	EX_TABLE_UA_LOAD_REG(0b, 5b, %[rc], %[prev])
	EX_TABLE_UA_LOAD_REG(1b, 5b, %[rc], %[prev])
	EX_TABLE_UA_LOAD_REG(3b, 5b, %[rc], %[prev])
	EX_TABLE_UA_LOAD_REG(4b, 5b, %[rc], %[prev])
	SKEY_REGION(20b, 21b)
	: [rc] "+&d" (rc),
	[prev] "=&d" (prev),
	[address] "+Q" ((int )address),
	[tmp] "+&d" (old),
	[new] "+&d" (new),
	[mask] "+&d" (mask),
	[count] "=a" (count)
	: [key] "%[count]" (key << 4),
	[default_key] "J" (PAGE_DEFAULT_KEY),
	[max_loops] "J" (CMPXCHG_USER_KEY_MAX_LOOPS)
	: "memory", "cc");
	disable_sacf_uaccess(sacf_flag);
	*uval = prev;
	if (!count)
	rc = -EAGAIN;
	return rc;
	}

	int __kprobes __cmpxchg_user_key1(unsigned long address, unsigned char *uval,
	unsigned char old, unsigned char new, unsigned long key)
	{
	unsigned int prev, shift, mask, _old, _new;
	int rc;

	shift = (3 ^ (address & 3)) << 3;
	address ^= address & 3;
	_old = (unsigned int)old << shift;
	_new = (unsigned int)new << shift;
	mask = ~(0xff << shift);
	rc = __cmpxchg_user_key_small(address, &prev, _old, _new, mask, key);
	*uval = prev >> shift;
	return rc;
	}
	EXPORT_SYMBOL(__cmpxchg_user_key1);

	int __kprobes __cmpxchg_user_key2(unsigned long address, unsigned short *uval,
	unsigned short old, unsigned short new, unsigned long key)
	{
	unsigned int prev, shift, mask, _old, _new;
	int rc;

	shift = (2 ^ (address & 2)) << 3;
	address ^= address & 2;
	_old = (unsigned int)old << shift;
	_new = (unsigned int)new << shift;
	mask = ~(0xffff << shift);
	rc = __cmpxchg_user_key_small(address, &prev, _old, _new, mask, key);
	*uval = prev >> shift;
	return rc;
	}
	EXPORT_SYMBOL(__cmpxchg_user_key2);

	int __kprobes __cmpxchg_user_key4(unsigned long address, unsigned int *uval,
	unsigned int old, unsigned int new, unsigned long key)
	{
	unsigned int prev = old;
	bool sacf_flag;
	int rc = 0;

	skey_regions_initialize();
	sacf_flag = enable_sacf_uaccess();
	asm_inline volatile(
	"20: spka 0(%[key])\n"
	" sacf 256\n"
	"0: cs %[prev],%[new],%[address]\n"
	"1: sacf 768\n"
	" spka %[default_key]\n"
	"21:\n"
	EX_TABLE_UA_LOAD_REG(0b, 1b, %[rc], %[prev])
	EX_TABLE_UA_LOAD_REG(1b, 1b, %[rc], %[prev])
	SKEY_REGION(20b, 21b)
	: [rc] "+&d" (rc),
	[prev] "+&d" (prev),
	[address] "+Q" ((int )address)
	: [new] "d" (new),
	[key] "a" (key << 4),
	[default_key] "J" (PAGE_DEFAULT_KEY)
	: "memory", "cc");
	disable_sacf_uaccess(sacf_flag);
	*uval = prev;
	return rc;
	}
	EXPORT_SYMBOL(__cmpxchg_user_key4);

	int __kprobes __cmpxchg_user_key8(unsigned long address, unsigned long *uval,
	unsigned long old, unsigned long new, unsigned long key)
	{
	unsigned long prev = old;
	bool sacf_flag;
	int rc = 0;

	skey_regions_initialize();
	sacf_flag = enable_sacf_uaccess();
	asm_inline volatile(
	"20: spka 0(%[key])\n"
	" sacf 256\n"
	"0: csg %[prev],%[new],%[address]\n"
	"1: sacf 768\n"
	" spka %[default_key]\n"
	"21:\n"
	EX_TABLE_UA_LOAD_REG(0b, 1b, %[rc], %[prev])
	EX_TABLE_UA_LOAD_REG(1b, 1b, %[rc], %[prev])
	SKEY_REGION(20b, 21b)
	: [rc] "+&d" (rc),
	[prev] "+&d" (prev),
	[address] "+QS" ((long )address)
	: [new] "d" (new),
	[key] "a" (key << 4),
	[default_key] "J" (PAGE_DEFAULT_KEY)
	: "memory", "cc");
	disable_sacf_uaccess(sacf_flag);
	*uval = prev;
	return rc;
	}
	EXPORT_SYMBOL(__cmpxchg_user_key8);

	int __kprobes __cmpxchg_user_key16(unsigned long address, __uint128_t *uval,
	__uint128_t old, __uint128_t new, unsigned long key)
	{
	__uint128_t prev = old;
	bool sacf_flag;
	int rc = 0;

	skey_regions_initialize();
	sacf_flag = enable_sacf_uaccess();
	asm_inline volatile(
	"20: spka 0(%[key])\n"
	" sacf 256\n"
	"0: cdsg %[prev],%[new],%[address]\n"
	"1: sacf 768\n"
	" spka %[default_key]\n"
	"21:\n"
	EX_TABLE_UA_LOAD_REGPAIR(0b, 1b, %[rc], %[prev])
	EX_TABLE_UA_LOAD_REGPAIR(1b, 1b, %[rc], %[prev])
	SKEY_REGION(20b, 21b)
	: [rc] "+&d" (rc),
	[prev] "+&d" (prev),
	[address] "+QS" ((__int128_t )address)
	: [new] "d" (new),
	[key] "a" (key << 4),
	[default_key] "J" (PAGE_DEFAULT_KEY)
	: "memory", "cc");
	disable_sacf_uaccess(sacf_flag);
	*uval = prev;
	return rc;
	}
	EXPORT_SYMBOL(__cmpxchg_user_key16);