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-rw-r--r--arch/x86/include/asm/fpu/internal.h540
1 files changed, 0 insertions, 540 deletions
diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index 5a18694a89b2..e69de29bb2d1 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -1,540 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 1994 Linus Torvalds
- *
- * Pentium III FXSR, SSE support
- * General FPU state handling cleanups
- * Gareth Hughes <gareth@valinux.com>, May 2000
- * x86-64 work by Andi Kleen 2002
- */
-
-#ifndef _ASM_X86_FPU_INTERNAL_H
-#define _ASM_X86_FPU_INTERNAL_H
-
-#include <linux/compat.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/mm.h>
-
-#include <asm/user.h>
-#include <asm/fpu/api.h>
-#include <asm/fpu/xstate.h>
-#include <asm/fpu/xcr.h>
-#include <asm/cpufeature.h>
-#include <asm/trace/fpu.h>
-
-/*
- * High level FPU state handling functions:
- */
-extern int fpu__restore_sig(void __user *buf, int ia32_frame);
-extern void fpu__drop(struct fpu *fpu);
-extern void fpu__clear_user_states(struct fpu *fpu);
-extern int fpu__exception_code(struct fpu *fpu, int trap_nr);
-
-extern void fpu_sync_fpstate(struct fpu *fpu);
-
-/* Clone and exit operations */
-extern int fpu_clone(struct task_struct *dst);
-extern void fpu_flush_thread(void);
-
-/*
- * Boot time FPU initialization functions:
- */
-extern void fpu__init_cpu(void);
-extern void fpu__init_system_xstate(void);
-extern void fpu__init_cpu_xstate(void);
-extern void fpu__init_system(struct cpuinfo_x86 *c);
-extern void fpu__init_check_bugs(void);
-extern void fpu__resume_cpu(void);
-
-/*
- * Debugging facility:
- */
-#ifdef CONFIG_X86_DEBUG_FPU
-# define WARN_ON_FPU(x) WARN_ON_ONCE(x)
-#else
-# define WARN_ON_FPU(x) ({ (void)(x); 0; })
-#endif
-
-/*
- * FPU related CPU feature flag helper routines:
- */
-static __always_inline __pure bool use_xsaveopt(void)
-{
- return static_cpu_has(X86_FEATURE_XSAVEOPT);
-}
-
-static __always_inline __pure bool use_xsave(void)
-{
- return static_cpu_has(X86_FEATURE_XSAVE);
-}
-
-static __always_inline __pure bool use_fxsr(void)
-{
- return static_cpu_has(X86_FEATURE_FXSR);
-}
-
-/*
- * fpstate handling functions:
- */
-
-extern union fpregs_state init_fpstate;
-
-extern void fpstate_init(union fpregs_state *state);
-#ifdef CONFIG_MATH_EMULATION
-extern void fpstate_init_soft(struct swregs_state *soft);
-#else
-static inline void fpstate_init_soft(struct swregs_state *soft) {}
-#endif
-extern void save_fpregs_to_fpstate(struct fpu *fpu);
-
-/* Returns 0 or the negated trap number, which results in -EFAULT for #PF */
-#define user_insn(insn, output, input...) \
-({ \
- int err; \
- \
- might_fault(); \
- \
- asm volatile(ASM_STAC "\n" \
- "1: " #insn "\n" \
- "2: " ASM_CLAC "\n" \
- ".section .fixup,\"ax\"\n" \
- "3: negl %%eax\n" \
- " jmp 2b\n" \
- ".previous\n" \
- _ASM_EXTABLE_FAULT(1b, 3b) \
- : [err] "=a" (err), output \
- : "0"(0), input); \
- err; \
-})
-
-#define kernel_insn_err(insn, output, input...) \
-({ \
- int err; \
- asm volatile("1:" #insn "\n\t" \
- "2:\n" \
- ".section .fixup,\"ax\"\n" \
- "3: movl $-1,%[err]\n" \
- " jmp 2b\n" \
- ".previous\n" \
- _ASM_EXTABLE(1b, 3b) \
- : [err] "=r" (err), output \
- : "0"(0), input); \
- err; \
-})
-
-#define kernel_insn(insn, output, input...) \
- asm volatile("1:" #insn "\n\t" \
- "2:\n" \
- _ASM_EXTABLE_HANDLE(1b, 2b, ex_handler_fprestore) \
- : output : input)
-
-static inline int fnsave_to_user_sigframe(struct fregs_state __user *fx)
-{
- return user_insn(fnsave %[fx]; fwait, [fx] "=m" (*fx), "m" (*fx));
-}
-
-static inline int fxsave_to_user_sigframe(struct fxregs_state __user *fx)
-{
- if (IS_ENABLED(CONFIG_X86_32))
- return user_insn(fxsave %[fx], [fx] "=m" (*fx), "m" (*fx));
- else
- return user_insn(fxsaveq %[fx], [fx] "=m" (*fx), "m" (*fx));
-
-}
-
-static inline void fxrstor(struct fxregs_state *fx)
-{
- if (IS_ENABLED(CONFIG_X86_32))
- kernel_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
- else
- kernel_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
-}
-
-static inline int fxrstor_safe(struct fxregs_state *fx)
-{
- if (IS_ENABLED(CONFIG_X86_32))
- return kernel_insn_err(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
- else
- return kernel_insn_err(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
-}
-
-static inline int fxrstor_from_user_sigframe(struct fxregs_state __user *fx)
-{
- if (IS_ENABLED(CONFIG_X86_32))
- return user_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
- else
- return user_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
-}
-
-static inline void frstor(struct fregs_state *fx)
-{
- kernel_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
-}
-
-static inline int frstor_safe(struct fregs_state *fx)
-{
- return kernel_insn_err(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
-}
-
-static inline int frstor_from_user_sigframe(struct fregs_state __user *fx)
-{
- return user_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
-}
-
-static inline void fxsave(struct fxregs_state *fx)
-{
- if (IS_ENABLED(CONFIG_X86_32))
- asm volatile( "fxsave %[fx]" : [fx] "=m" (*fx));
- else
- asm volatile("fxsaveq %[fx]" : [fx] "=m" (*fx));
-}
-
-/* These macros all use (%edi)/(%rdi) as the single memory argument. */
-#define XSAVE ".byte " REX_PREFIX "0x0f,0xae,0x27"
-#define XSAVEOPT ".byte " REX_PREFIX "0x0f,0xae,0x37"
-#define XSAVES ".byte " REX_PREFIX "0x0f,0xc7,0x2f"
-#define XRSTOR ".byte " REX_PREFIX "0x0f,0xae,0x2f"
-#define XRSTORS ".byte " REX_PREFIX "0x0f,0xc7,0x1f"
-
-/*
- * After this @err contains 0 on success or the negated trap number when
- * the operation raises an exception. For faults this results in -EFAULT.
- */
-#define XSTATE_OP(op, st, lmask, hmask, err) \
- asm volatile("1:" op "\n\t" \
- "xor %[err], %[err]\n" \
- "2:\n\t" \
- ".pushsection .fixup,\"ax\"\n\t" \
- "3: negl %%eax\n\t" \
- "jmp 2b\n\t" \
- ".popsection\n\t" \
- _ASM_EXTABLE_FAULT(1b, 3b) \
- : [err] "=a" (err) \
- : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
- : "memory")
-
-/*
- * If XSAVES is enabled, it replaces XSAVEOPT because it supports a compact
- * format and supervisor states in addition to modified optimization in
- * XSAVEOPT.
- *
- * Otherwise, if XSAVEOPT is enabled, XSAVEOPT replaces XSAVE because XSAVEOPT
- * supports modified optimization which is not supported by XSAVE.
- *
- * We use XSAVE as a fallback.
- *
- * The 661 label is defined in the ALTERNATIVE* macros as the address of the
- * original instruction which gets replaced. We need to use it here as the
- * address of the instruction where we might get an exception at.
- */
-#define XSTATE_XSAVE(st, lmask, hmask, err) \
- asm volatile(ALTERNATIVE_2(XSAVE, \
- XSAVEOPT, X86_FEATURE_XSAVEOPT, \
- XSAVES, X86_FEATURE_XSAVES) \
- "\n" \
- "xor %[err], %[err]\n" \
- "3:\n" \
- ".pushsection .fixup,\"ax\"\n" \
- "4: movl $-2, %[err]\n" \
- "jmp 3b\n" \
- ".popsection\n" \
- _ASM_EXTABLE(661b, 4b) \
- : [err] "=r" (err) \
- : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
- : "memory")
-
-/*
- * Use XRSTORS to restore context if it is enabled. XRSTORS supports compact
- * XSAVE area format.
- */
-#define XSTATE_XRESTORE(st, lmask, hmask) \
- asm volatile(ALTERNATIVE(XRSTOR, \
- XRSTORS, X86_FEATURE_XSAVES) \
- "\n" \
- "3:\n" \
- _ASM_EXTABLE_HANDLE(661b, 3b, ex_handler_fprestore)\
- : \
- : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
- : "memory")
-
-/*
- * This function is called only during boot time when x86 caps are not set
- * up and alternative can not be used yet.
- */
-static inline void os_xrstor_booting(struct xregs_state *xstate)
-{
- u64 mask = xfeatures_mask_fpstate();
- u32 lmask = mask;
- u32 hmask = mask >> 32;
- int err;
-
- WARN_ON(system_state != SYSTEM_BOOTING);
-
- if (boot_cpu_has(X86_FEATURE_XSAVES))
- XSTATE_OP(XRSTORS, xstate, lmask, hmask, err);
- else
- XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
-
- /*
- * We should never fault when copying from a kernel buffer, and the FPU
- * state we set at boot time should be valid.
- */
- WARN_ON_FPU(err);
-}
-
-/*
- * Save processor xstate to xsave area.
- *
- * Uses either XSAVE or XSAVEOPT or XSAVES depending on the CPU features
- * and command line options. The choice is permanent until the next reboot.
- */
-static inline void os_xsave(struct xregs_state *xstate)
-{
- u64 mask = xfeatures_mask_all;
- u32 lmask = mask;
- u32 hmask = mask >> 32;
- int err;
-
- WARN_ON_FPU(!alternatives_patched);
-
- XSTATE_XSAVE(xstate, lmask, hmask, err);
-
- /* We should never fault when copying to a kernel buffer: */
- WARN_ON_FPU(err);
-}
-
-/*
- * Restore processor xstate from xsave area.
- *
- * Uses XRSTORS when XSAVES is used, XRSTOR otherwise.
- */
-static inline void os_xrstor(struct xregs_state *xstate, u64 mask)
-{
- u32 lmask = mask;
- u32 hmask = mask >> 32;
-
- XSTATE_XRESTORE(xstate, lmask, hmask);
-}
-
-/*
- * Save xstate to user space xsave area.
- *
- * We don't use modified optimization because xrstor/xrstors might track
- * a different application.
- *
- * We don't use compacted format xsave area for
- * backward compatibility for old applications which don't understand
- * compacted format of xsave area.
- */
-static inline int xsave_to_user_sigframe(struct xregs_state __user *buf)
-{
- /*
- * Include the features which are not xsaved/rstored by the kernel
- * internally, e.g. PKRU. That's user space ABI and also required
- * to allow the signal handler to modify PKRU.
- */
- u64 mask = xfeatures_mask_uabi();
- u32 lmask = mask;
- u32 hmask = mask >> 32;
- int err;
-
- /*
- * Clear the xsave header first, so that reserved fields are
- * initialized to zero.
- */
- err = __clear_user(&buf->header, sizeof(buf->header));
- if (unlikely(err))
- return -EFAULT;
-
- stac();
- XSTATE_OP(XSAVE, buf, lmask, hmask, err);
- clac();
-
- return err;
-}
-
-/*
- * Restore xstate from user space xsave area.
- */
-static inline int xrstor_from_user_sigframe(struct xregs_state __user *buf, u64 mask)
-{
- struct xregs_state *xstate = ((__force struct xregs_state *)buf);
- u32 lmask = mask;
- u32 hmask = mask >> 32;
- int err;
-
- stac();
- XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
- clac();
-
- return err;
-}
-
-/*
- * Restore xstate from kernel space xsave area, return an error code instead of
- * an exception.
- */
-static inline int os_xrstor_safe(struct xregs_state *xstate, u64 mask)
-{
- u32 lmask = mask;
- u32 hmask = mask >> 32;
- int err;
-
- if (cpu_feature_enabled(X86_FEATURE_XSAVES))
- XSTATE_OP(XRSTORS, xstate, lmask, hmask, err);
- else
- XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
-
- return err;
-}
-
-extern void __restore_fpregs_from_fpstate(union fpregs_state *fpstate, u64 mask);
-
-static inline void restore_fpregs_from_fpstate(union fpregs_state *fpstate)
-{
- __restore_fpregs_from_fpstate(fpstate, xfeatures_mask_fpstate());
-}
-
-extern int copy_fpstate_to_sigframe(void __user *buf, void __user *fp, int size);
-
-/*
- * FPU context switch related helper methods:
- */
-
-DECLARE_PER_CPU(struct fpu *, fpu_fpregs_owner_ctx);
-
-/*
- * The in-register FPU state for an FPU context on a CPU is assumed to be
- * valid if the fpu->last_cpu matches the CPU, and the fpu_fpregs_owner_ctx
- * matches the FPU.
- *
- * If the FPU register state is valid, the kernel can skip restoring the
- * FPU state from memory.
- *
- * Any code that clobbers the FPU registers or updates the in-memory
- * FPU state for a task MUST let the rest of the kernel know that the
- * FPU registers are no longer valid for this task.
- *
- * Either one of these invalidation functions is enough. Invalidate
- * a resource you control: CPU if using the CPU for something else
- * (with preemption disabled), FPU for the current task, or a task that
- * is prevented from running by the current task.
- */
-static inline void __cpu_invalidate_fpregs_state(void)
-{
- __this_cpu_write(fpu_fpregs_owner_ctx, NULL);
-}
-
-static inline void __fpu_invalidate_fpregs_state(struct fpu *fpu)
-{
- fpu->last_cpu = -1;
-}
-
-static inline int fpregs_state_valid(struct fpu *fpu, unsigned int cpu)
-{
- return fpu == this_cpu_read(fpu_fpregs_owner_ctx) && cpu == fpu->last_cpu;
-}
-
-/*
- * These generally need preemption protection to work,
- * do try to avoid using these on their own:
- */
-static inline void fpregs_deactivate(struct fpu *fpu)
-{
- this_cpu_write(fpu_fpregs_owner_ctx, NULL);
- trace_x86_fpu_regs_deactivated(fpu);
-}
-
-static inline void fpregs_activate(struct fpu *fpu)
-{
- this_cpu_write(fpu_fpregs_owner_ctx, fpu);
- trace_x86_fpu_regs_activated(fpu);
-}
-
-/* Internal helper for switch_fpu_return() and signal frame setup */
-static inline void fpregs_restore_userregs(void)
-{
- struct fpu *fpu = &current->thread.fpu;
- int cpu = smp_processor_id();
-
- if (WARN_ON_ONCE(current->flags & PF_KTHREAD))
- return;
-
- if (!fpregs_state_valid(fpu, cpu)) {
- u64 mask;
-
- /*
- * This restores _all_ xstate which has not been
- * established yet.
- *
- * If PKRU is enabled, then the PKRU value is already
- * correct because it was either set in switch_to() or in
- * flush_thread(). So it is excluded because it might be
- * not up to date in current->thread.fpu.xsave state.
- */
- mask = xfeatures_mask_restore_user() |
- xfeatures_mask_supervisor();
- __restore_fpregs_from_fpstate(&fpu->state, mask);
-
- fpregs_activate(fpu);
- fpu->last_cpu = cpu;
- }
- clear_thread_flag(TIF_NEED_FPU_LOAD);
-}
-
-/*
- * FPU state switching for scheduling.
- *
- * This is a two-stage process:
- *
- * - switch_fpu_prepare() saves the old state.
- * This is done within the context of the old process.
- *
- * - switch_fpu_finish() sets TIF_NEED_FPU_LOAD; the floating point state
- * will get loaded on return to userspace, or when the kernel needs it.
- *
- * If TIF_NEED_FPU_LOAD is cleared then the CPU's FPU registers
- * are saved in the current thread's FPU register state.
- *
- * If TIF_NEED_FPU_LOAD is set then CPU's FPU registers may not
- * hold current()'s FPU registers. It is required to load the
- * registers before returning to userland or using the content
- * otherwise.
- *
- * The FPU context is only stored/restored for a user task and
- * PF_KTHREAD is used to distinguish between kernel and user threads.
- */
-static inline void switch_fpu_prepare(struct fpu *old_fpu, int cpu)
-{
- if (static_cpu_has(X86_FEATURE_FPU) && !(current->flags & PF_KTHREAD)) {
- save_fpregs_to_fpstate(old_fpu);
- /*
- * The save operation preserved register state, so the
- * fpu_fpregs_owner_ctx is still @old_fpu. Store the
- * current CPU number in @old_fpu, so the next return
- * to user space can avoid the FPU register restore
- * when is returns on the same CPU and still owns the
- * context.
- */
- old_fpu->last_cpu = cpu;
-
- trace_x86_fpu_regs_deactivated(old_fpu);
- }
-}
-
-/*
- * Misc helper functions:
- */
-
-/*
- * Delay loading of the complete FPU state until the return to userland.
- * PKRU is handled separately.
- */
-static inline void switch_fpu_finish(struct fpu *new_fpu)
-{
- if (cpu_feature_enabled(X86_FEATURE_FPU))
- set_thread_flag(TIF_NEED_FPU_LOAD);
-}
-
-#endif /* _ASM_X86_FPU_INTERNAL_H */
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.