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diff --git a/arch/s390/include/asm/fpu/api.h b/arch/s390/include/asm/fpu/api.h
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-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * In-kernel FPU support functions
- *
- *
- * Consider these guidelines before using in-kernel FPU functions:
- *
- * 1. Use kernel_fpu_begin() and kernel_fpu_end() to enclose all in-kernel
- * use of floating-point or vector registers and instructions.
- *
- * 2. For kernel_fpu_begin(), specify the vector register range you want to
- * use with the KERNEL_VXR_* constants. Consider these usage guidelines:
- *
- * a) If your function typically runs in process-context, use the lower
- * half of the vector registers, for example, specify KERNEL_VXR_LOW.
- * b) If your function typically runs in soft-irq or hard-irq context,
- * prefer using the upper half of the vector registers, for example,
- * specify KERNEL_VXR_HIGH.
- *
- * If you adhere to these guidelines, an interrupted process context
- * does not require to save and restore vector registers because of
- * disjoint register ranges.
- *
- * Also note that the __kernel_fpu_begin()/__kernel_fpu_end() functions
- * includes logic to save and restore up to 16 vector registers at once.
- *
- * 3. You can nest kernel_fpu_begin()/kernel_fpu_end() by using different
- * struct kernel_fpu states. Vector registers that are in use by outer
- * levels are saved and restored. You can minimize the save and restore
- * effort by choosing disjoint vector register ranges.
- *
- * 5. To use vector floating-point instructions, specify the KERNEL_FPC
- * flag to save and restore floating-point controls in addition to any
- * vector register range.
- *
- * 6. To use floating-point registers and instructions only, specify the
- * KERNEL_FPR flag. This flag triggers a save and restore of vector
- * registers V0 to V15 and floating-point controls.
- *
- * Copyright IBM Corp. 2015
- * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
- */
-
-#ifndef _ASM_S390_FPU_API_H
-#define _ASM_S390_FPU_API_H
-
-#include <linux/preempt.h>
-#include <asm/asm-extable.h>
-#include <asm/fpu/internal.h>
-
-void save_fpu_regs(void);
-void load_fpu_regs(void);
-void __load_fpu_regs(void);
-
-/**
- * sfpc_safe - Set floating point control register safely.
- * @fpc: new value for floating point control register
- *
- * Set floating point control register. This may lead to an exception,
- * since a saved value may have been modified by user space (ptrace,
- * signal return, kvm registers) to an invalid value. In such a case
- * set the floating point control register to zero.
- */
-static inline void sfpc_safe(u32 fpc)
-{
- asm volatile("\n"
- "0: sfpc %[fpc]\n"
- "1: nopr %%r7\n"
- ".pushsection .fixup, \"ax\"\n"
- "2: lghi %[fpc],0\n"
- " jg 0b\n"
- ".popsection\n"
- EX_TABLE(1b, 2b)
- : [fpc] "+d" (fpc)
- : : "memory");
-}
-
-#define KERNEL_FPC 1
-#define KERNEL_VXR_V0V7 2
-#define KERNEL_VXR_V8V15 4
-#define KERNEL_VXR_V16V23 8
-#define KERNEL_VXR_V24V31 16
-
-#define KERNEL_VXR_LOW (KERNEL_VXR_V0V7|KERNEL_VXR_V8V15)
-#define KERNEL_VXR_MID (KERNEL_VXR_V8V15|KERNEL_VXR_V16V23)
-#define KERNEL_VXR_HIGH (KERNEL_VXR_V16V23|KERNEL_VXR_V24V31)
-
-#define KERNEL_VXR (KERNEL_VXR_LOW|KERNEL_VXR_HIGH)
-#define KERNEL_FPR (KERNEL_FPC|KERNEL_VXR_LOW)
-
-struct kernel_fpu;
-
-/*
- * Note the functions below must be called with preemption disabled.
- * Do not enable preemption before calling __kernel_fpu_end() to prevent
- * an corruption of an existing kernel FPU state.
- *
- * Prefer using the kernel_fpu_begin()/kernel_fpu_end() pair of functions.
- */
-void __kernel_fpu_begin(struct kernel_fpu *state, u32 flags);
-void __kernel_fpu_end(struct kernel_fpu *state, u32 flags);
-
-
-static inline void kernel_fpu_begin(struct kernel_fpu *state, u32 flags)
-{
- preempt_disable();
- state->mask = S390_lowcore.fpu_flags;
- if (!test_cpu_flag(CIF_FPU))
- /* Save user space FPU state and register contents */
- save_fpu_regs();
- else if (state->mask & flags)
- /* Save FPU/vector register in-use by the kernel */
- __kernel_fpu_begin(state, flags);
- S390_lowcore.fpu_flags |= flags;
-}
-
-static inline void kernel_fpu_end(struct kernel_fpu *state, u32 flags)
-{
- S390_lowcore.fpu_flags = state->mask;
- if (state->mask & flags)
- /* Restore FPU/vector register in-use by the kernel */
- __kernel_fpu_end(state, flags);
- preempt_enable();
-}
-
-#endif /* _ASM_S390_FPU_API_H */