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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/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 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)
/* All currently supported supervisor features */
#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (0)
/*
* 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 dynamic supervisor features are set in this mask.
*
* Unlike the existing supported supervisor features, a dynamic 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 a dynamic 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 dynamic supervisor feature in
* IA32_XSS at run time, since it has been set at boot time.
*/
#define XFEATURE_MASK_DYNAMIC (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)
/* All supervisor states including supported and unsupported states. */
#define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \
XFEATURE_MASK_DYNAMIC | \
XFEATURE_MASK_SUPERVISOR_UNSUPPORTED)
#ifdef CONFIG_X86_64
#define REX_PREFIX "0x48, "
#else
#define REX_PREFIX
#endif
extern u64 xfeatures_mask_all;
static inline u64 xfeatures_mask_supervisor(void)
{
return xfeatures_mask_all & XFEATURE_MASK_SUPERVISOR_SUPPORTED;
}
static inline u64 xfeatures_mask_user(void)
{
return xfeatures_mask_all & XFEATURE_MASK_USER_SUPPORTED;
}
static inline u64 xfeatures_mask_dynamic(void)
{
if (!boot_cpu_has(X86_FEATURE_ARCH_LBR))
return XFEATURE_MASK_DYNAMIC & ~XFEATURE_MASK_LBR;
return XFEATURE_MASK_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);
void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
const void *get_xsave_field_ptr(int xfeature_nr);
int using_compacted_format(void);
int xfeature_size(int xfeature_nr);
struct membuf;
void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave);
int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
void copy_supervisor_to_kernel(struct xregs_state *xsave);
void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask);
void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask);
/* Validate an xstate header supplied by userspace (ptrace or sigreturn) */
int validate_user_xstate_header(const struct xstate_header *hdr);
#endif
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