/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __ASM_X86_XSAVE_H #define __ASM_X86_XSAVE_H #include <linux/uaccess.h> #include <linux/types.h> #include <asm/processor.h> #include <asm/fpu/api.h> #include <asm/user.h> /* Bit 63 of XCR0 is reserved for future expansion */ #define XFEATURE_MASK_EXTEND … #define XSTATE_CPUID … #define TILE_CPUID … #define FXSAVE_SIZE … #define XSAVE_HDR_SIZE … #define XSAVE_HDR_OFFSET … #define XSAVE_YMM_SIZE … #define XSAVE_YMM_OFFSET … #define XSAVE_ALIGNMENT … /* All currently supported user features */ #define XFEATURE_MASK_USER_SUPPORTED … /* * Features which are restored when returning to user space. * PKRU is not restored on return to user space because PKRU * is switched eagerly in switch_to() and flush_thread() */ #define XFEATURE_MASK_USER_RESTORE … /* Features which are dynamically enabled for a process on request */ #define XFEATURE_MASK_USER_DYNAMIC … /* All currently supported supervisor features */ #define XFEATURE_MASK_SUPERVISOR_SUPPORTED … /* * A supervisor state component may not always contain valuable information, * and its size may be huge. Saving/restoring such supervisor state components * at each context switch can cause high CPU and space overhead, which should * be avoided. Such supervisor state components should only be saved/restored * on demand. The on-demand supervisor features are set in this mask. * * Unlike the existing supported supervisor features, an independent supervisor * feature does not allocate a buffer in task->fpu, and the corresponding * supervisor state component cannot be saved/restored at each context switch. * * To support an independent supervisor feature, a developer should follow the * dos and don'ts as below: * - Do dynamically allocate a buffer for the supervisor state component. * - Do manually invoke the XSAVES/XRSTORS instruction to save/restore the * state component to/from the buffer. * - Don't set the bit corresponding to the independent supervisor feature in * IA32_XSS at run time, since it has been set at boot time. */ #define XFEATURE_MASK_INDEPENDENT … /* * Unsupported supervisor features. When a supervisor feature in this mask is * supported in the future, move it to the supported supervisor feature mask. */ #define XFEATURE_MASK_SUPERVISOR_UNSUPPORTED … /* All supervisor states including supported and unsupported states. */ #define XFEATURE_MASK_SUPERVISOR_ALL … /* * The feature mask required to restore FPU state: * - All user states which are not eagerly switched in switch_to()/exec() * - The suporvisor states */ #define XFEATURE_MASK_FPSTATE … /* * Features in this mask have space allocated in the signal frame, but may not * have that space initialized when the feature is in its init state. */ #define XFEATURE_MASK_SIGFRAME_INITOPT … extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; extern void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask); int xfeature_size(int xfeature_nr); void xsaves(struct xregs_state *xsave, u64 mask); void xrstors(struct xregs_state *xsave, u64 mask); int xfd_enable_feature(u64 xfd_err); #ifdef CONFIG_X86_64 DECLARE_STATIC_KEY_FALSE(__fpu_state_size_dynamic); #endif #ifdef CONFIG_X86_64 DECLARE_STATIC_KEY_FALSE(__fpu_state_size_dynamic); static __always_inline __pure bool fpu_state_size_dynamic(void) { … } #else static __always_inline __pure bool fpu_state_size_dynamic(void) { return false; } #endif #endif
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