1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef __X86_KERNEL_FPU_LEGACY_H
  3#define __X86_KERNEL_FPU_LEGACY_H
  4
  5#include <asm/fpu/types.h>
  6
  7extern unsigned int mxcsr_feature_mask;
  8
  9static inline void ldmxcsr(u32 mxcsr)
 10{
 11	asm volatile("ldmxcsr %0" :: "m" (mxcsr));
 12}
 13
 14/*
 15 * Returns 0 on success or the trap number when the operation raises an
 16 * exception.
 17 */
 18#define user_insn(insn, output, input...)				\
 19({									\
 20	int err;							\
 21									\
 22	might_fault();							\
 23									\
 24	asm volatile(ASM_STAC "\n"					\
 25		     "1: " #insn "\n"					\
 26		     "2: " ASM_CLAC "\n"				\
 27		     _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_MCE_SAFE)	\
 28		     : [err] "=a" (err), output				\
 29		     : "0"(0), input);					\
 30	err;								\
 31})
 32
 33#define kernel_insn_err(insn, output, input...)				\
 34({									\
 35	int err;							\
 36	asm volatile("1:" #insn "\n\t"					\
 37		     "2:\n"						\
 38		     _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, %[err]) \
 39		     : [err] "=r" (err), output				\
 40		     : "0"(0), input);					\
 41	err;								\
 42})
 43
 44#define kernel_insn(insn, output, input...)				\
 45	asm volatile("1:" #insn "\n\t"					\
 46		     "2:\n"						\
 47		     _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FPU_RESTORE)	\
 48		     : output : input)
 49
 50static inline int fnsave_to_user_sigframe(struct fregs_state __user *fx)
 51{
 52	return user_insn(fnsave %[fx]; fwait,  [fx] "=m" (*fx), "m" (*fx));
 53}
 54
 55static inline int fxsave_to_user_sigframe(struct fxregs_state __user *fx)
 56{
 57	if (IS_ENABLED(CONFIG_X86_32))
 58		return user_insn(fxsave %[fx], [fx] "=m" (*fx), "m" (*fx));
 59	else
 60		return user_insn(fxsaveq %[fx], [fx] "=m" (*fx), "m" (*fx));
 61
 62}
 63
 64static inline void fxrstor(struct fxregs_state *fx)
 65{
 66	if (IS_ENABLED(CONFIG_X86_32))
 67		kernel_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 68	else
 69		kernel_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
 70}
 71
 72static inline int fxrstor_safe(struct fxregs_state *fx)
 73{
 74	if (IS_ENABLED(CONFIG_X86_32))
 75		return kernel_insn_err(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 76	else
 77		return kernel_insn_err(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
 78}
 79
 80static inline int fxrstor_from_user_sigframe(struct fxregs_state __user *fx)
 81{
 82	if (IS_ENABLED(CONFIG_X86_32))
 83		return user_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 84	else
 85		return user_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
 86}
 87
 88static inline void frstor(struct fregs_state *fx)
 89{
 90	kernel_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 91}
 92
 93static inline int frstor_safe(struct fregs_state *fx)
 94{
 95	return kernel_insn_err(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
 96}
 97
 98static inline int frstor_from_user_sigframe(struct fregs_state __user *fx)
 99{
100	return user_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
101}
102
103static inline void fxsave(struct fxregs_state *fx)
104{
105	if (IS_ENABLED(CONFIG_X86_32))
106		asm volatile( "fxsave %[fx]" : [fx] "=m" (*fx));
107	else
108		asm volatile("fxsaveq %[fx]" : [fx] "=m" (*fx));
109}
110
111#endif