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#ifndef __ASM_X86_XSAVE_H
#define __ASM_X86_XSAVE_H
#include <linux/types.h>
#include <asm/processor.h>
#include <linux/uaccess.h>
/* Bit 63 of XCR0 is reserved for future expansion */
#define XSTATE_EXTEND_MASK (~(XSTATE_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)
/* Supported features which support lazy state saving */
#define XSTATE_LAZY (XSTATE_FP | XSTATE_SSE | XSTATE_YMM \
| XSTATE_OPMASK | XSTATE_ZMM_Hi256 | XSTATE_Hi16_ZMM)
/* Supported features which require eager state saving */
#define XSTATE_EAGER (XSTATE_BNDREGS | XSTATE_BNDCSR)
/* All currently supported features */
#define XCNTXT_MASK (XSTATE_LAZY | XSTATE_EAGER)
#ifdef CONFIG_X86_64
#define REX_PREFIX "0x48, "
#else
#define REX_PREFIX
#endif
extern unsigned int xstate_size;
extern u64 xfeatures_mask;
extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask);
/* 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"
#define xstate_fault ".section .fixup,\"ax\"\n" \
"3: movl $-1,%[err]\n" \
" jmp 2b\n" \
".previous\n" \
_ASM_EXTABLE(1b, 3b) \
: [err] "=r" (err)
/*
* This function is called only during boot time when x86 caps are not set
* up and alternative can not be used yet.
*/
static inline int copy_xregs_to_kernel_booting(struct xregs_state *fx)
{
u64 mask = -1;
u32 lmask = mask;
u32 hmask = mask >> 32;
int err = 0;
WARN_ON(system_state != SYSTEM_BOOTING);
if (boot_cpu_has(X86_FEATURE_XSAVES))
asm volatile("1:"XSAVES"\n\t"
"2:\n\t"
xstate_fault
: "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
: "memory");
else
asm volatile("1:"XSAVE"\n\t"
"2:\n\t"
xstate_fault
: "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
: "memory");
return err;
}
/*
* This function is called only during boot time when x86 caps are not set
* up and alternative can not be used yet.
*/
static inline int copy_kernel_to_xregs_booting(struct xregs_state *fx, u64 mask)
{
u32 lmask = mask;
u32 hmask = mask >> 32;
int err = 0;
WARN_ON(system_state != SYSTEM_BOOTING);
if (boot_cpu_has(X86_FEATURE_XSAVES))
asm volatile("1:"XRSTORS"\n\t"
"2:\n\t"
xstate_fault
: "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
: "memory");
else
asm volatile("1:"XRSTOR"\n\t"
"2:\n\t"
xstate_fault
: "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
: "memory");
return err;
}
/*
* Save processor xstate to xsave area.
*/
static inline int copy_xregs_to_kernel(struct xregs_state *fx)
{
u64 mask = -1;
u32 lmask = mask;
u32 hmask = mask >> 32;
int err = 0;
WARN_ON(!alternatives_patched);
/*
* If xsaves is enabled, xsaves replaces xsaveopt because
* it supports 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.
*
* If none of xsaves and xsaveopt is enabled, use xsave.
*/
alternative_input_2(
"1:"XSAVE,
XSAVEOPT,
X86_FEATURE_XSAVEOPT,
XSAVES,
X86_FEATURE_XSAVES,
[fx] "D" (fx), "a" (lmask), "d" (hmask) :
"memory");
asm volatile("2:\n\t"
xstate_fault
: "0" (0)
: "memory");
return err;
}
/*
* Restore processor xstate from xsave area.
*/
static inline int copy_kernel_to_xregs(struct xregs_state *fx, u64 mask)
{
int err = 0;
u32 lmask = mask;
u32 hmask = mask >> 32;
/*
* Use xrstors to restore context if it is enabled. xrstors supports
* compacted format of xsave area which is not supported by xrstor.
*/
alternative_input(
"1: " XRSTOR,
XRSTORS,
X86_FEATURE_XSAVES,
"D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
: "memory");
asm volatile("2:\n"
xstate_fault
: "0" (0)
: "memory");
return err;
}
/*
* 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 copy_xregs_to_user(struct xregs_state __user *buf)
{
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;
__asm__ __volatile__(ASM_STAC "\n"
"1:"XSAVE"\n"
"2: " ASM_CLAC "\n"
xstate_fault
: "D" (buf), "a" (-1), "d" (-1), "0" (0)
: "memory");
return err;
}
/*
* Restore xstate from user space xsave area.
*/
static inline int copy_user_to_xregs(struct xregs_state __user *buf, u64 mask)
{
int err = 0;
struct xregs_state *xstate = ((__force struct xregs_state *)buf);
u32 lmask = mask;
u32 hmask = mask >> 32;
__asm__ __volatile__(ASM_STAC "\n"
"1:"XRSTOR"\n"
"2: " ASM_CLAC "\n"
xstate_fault
: "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
: "memory"); /* memory required? */
return err;
}
void *get_xsave_addr(struct xregs_state *xsave, int xstate);
#endif
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