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authorThomas Zimmermann <tzimmermann@suse.de>2021-11-18 09:36:39 +0100
committerThomas Zimmermann <tzimmermann@suse.de>2021-11-18 09:36:39 +0100
commita713ca234ea9d946235ac7248995c5fddfd9e523 (patch)
tree708f72ee1c76360aa80c926f1defc8301aef1a23 /arch/x86/kernel/fpu/legacy.h
parentdrm/i915: Clarify probing order in intel_dp_aux_init_backlight_funcs() (diff)
parentLinux 5.16-rc1 (diff)
downloadlinux-dev-a713ca234ea9d946235ac7248995c5fddfd9e523.tar.xz
linux-dev-a713ca234ea9d946235ac7248995c5fddfd9e523.zip
Merge drm/drm-next into drm-misc-next
Backmerging from drm/drm-next for v5.16-rc1. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Diffstat (limited to 'arch/x86/kernel/fpu/legacy.h')
-rw-r--r--arch/x86/kernel/fpu/legacy.h115
1 files changed, 115 insertions, 0 deletions
diff --git a/arch/x86/kernel/fpu/legacy.h b/arch/x86/kernel/fpu/legacy.h
new file mode 100644
index 000000000000..17c26b164c63
--- /dev/null
+++ b/arch/x86/kernel/fpu/legacy.h
@@ -0,0 +1,115 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __X86_KERNEL_FPU_LEGACY_H
+#define __X86_KERNEL_FPU_LEGACY_H
+
+#include <asm/fpu/types.h>
+
+extern unsigned int mxcsr_feature_mask;
+
+static inline void ldmxcsr(u32 mxcsr)
+{
+ asm volatile("ldmxcsr %0" :: "m" (mxcsr));
+}
+
+/*
+ * Returns 0 on success or the trap number when the operation raises an
+ * exception.
+ */
+#define user_insn(insn, output, input...) \
+({ \
+ int err; \
+ \
+ might_fault(); \
+ \
+ asm volatile(ASM_STAC "\n" \
+ "1: " #insn "\n" \
+ "2: " ASM_CLAC "\n" \
+ _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_MCE_SAFE) \
+ : [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_TYPE(1b, 2b, EX_TYPE_FPU_RESTORE) \
+ : 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));
+}
+
+#endif