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/* 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 (~(XFEATURE_MASK_FPSSE | (1ULL << 63)))
#define XSTATE_CPUID 0x0000000d
#define TILE_CPUID 0x0000001d
#define FXSAVE_SIZE 512
#define XSAVE_HDR_SIZE 64
#define XSAVE_HDR_OFFSET FXSAVE_SIZE
#define XSAVE_YMM_SIZE 256
#define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
#define XSAVE_ALIGNMENT 64
/* All currently supported user features */
#define XFEATURE_MASK_USER_SUPPORTED (XFEATURE_MASK_FP | \
XFEATURE_MASK_SSE | \
XFEATURE_MASK_YMM | \
XFEATURE_MASK_OPMASK | \
XFEATURE_MASK_ZMM_Hi256 | \
XFEATURE_MASK_Hi16_ZMM | \
XFEATURE_MASK_PKRU | \
XFEATURE_MASK_BNDREGS | \
XFEATURE_MASK_BNDCSR | \
XFEATURE_MASK_XTILE)
/*
* 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 \
(XFEATURE_MASK_USER_SUPPORTED & ~XFEATURE_MASK_PKRU)
/* Features which are dynamically enabled for a process on request */
#define XFEATURE_MASK_USER_DYNAMIC XFEATURE_MASK_XTILE_DATA
/* All currently supported supervisor features */
#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID | \
XFEATURE_MASK_CET_USER)
/*
* 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 (XFEATURE_MASK_LBR)
/*
* 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 (XFEATURE_MASK_PT | \
XFEATURE_MASK_CET_KERNEL)
/* All supervisor states including supported and unsupported states. */
#define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \
XFEATURE_MASK_INDEPENDENT | \
XFEATURE_MASK_SUPERVISOR_UNSUPPORTED)
/*
* 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 (XFEATURE_MASK_USER_RESTORE | \
XFEATURE_MASK_SUPERVISOR_SUPPORTED)
/*
* 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 (XFEATURE_MASK_XTILE | \
XFEATURE_MASK_USER_DYNAMIC)
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)
{
return static_branch_unlikely(&__fpu_state_size_dynamic);
}
#else
static __always_inline __pure bool fpu_state_size_dynamic(void)
{
return false;
}
#endif
#endif
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