Commit 32b09c23 authored by H. Peter Anvin (Intel)'s avatar H. Peter Anvin (Intel) Committed by Borislav Petkov (AMD)
Browse files

x86/fred: Add a new header file for FRED definitions 



Add a header file for FRED prototypes and definitions.

Signed-off-by: default avatarH. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: default avatarXin Li <xin3.li@intel.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Tested-by: default avatarShan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-16-xin3.li@intel.com
parent 3c77bf02

arch/x86/include/asm/fred.h

0 → 100644
+68 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/*

 * Macros for Flexible Return and Event Delivery (FRED)

 */



#ifndef ASM_X86_FRED_H

#define ASM_X86_FRED_H



#include <linux/const.h>



#include <asm/asm.h>



/*

 * FRED event return instruction opcodes for ERET{S,U}; supported in

 * binutils >= 2.41.

 */

#define ERETS			_ASM_BYTES(0xf2,0x0f,0x01,0xca)

#define ERETU			_ASM_BYTES(0xf3,0x0f,0x01,0xca)



/*

 * RSP is aligned to a 64-byte boundary before used to push a new stack frame

 */

#define FRED_STACK_FRAME_RSP_MASK	_AT(unsigned long, (~0x3f))



/*

 * Used for the return address for call emulation during code patching,

 * and measured in 64-byte cache lines.

 */

#define FRED_CONFIG_REDZONE_AMOUNT	1

#define FRED_CONFIG_REDZONE		(_AT(unsigned long, FRED_CONFIG_REDZONE_AMOUNT) << 6)

#define FRED_CONFIG_INT_STKLVL(l)	(_AT(unsigned long, l) << 9)

#define FRED_CONFIG_ENTRYPOINT(p)	_AT(unsigned long, (p))



#ifndef __ASSEMBLY__



#ifdef CONFIG_X86_FRED

#include <linux/kernel.h>



#include <asm/ptrace.h>



struct fred_info {

	/* Event data: CR2, DR6, ... */

	unsigned long edata;

	unsigned long resv;

};



/* Full format of the FRED stack frame */

struct fred_frame {

	struct pt_regs   regs;

	struct fred_info info;

};



static __always_inline struct fred_info *fred_info(struct pt_regs *regs)

{

	return &container_of(regs, struct fred_frame, regs)->info;

}



static __always_inline unsigned long fred_event_data(struct pt_regs *regs)

{

	return fred_info(regs)->edata;

}



#else /* CONFIG_X86_FRED */

static __always_inline unsigned long fred_event_data(struct pt_regs *regs) { return 0; }

#endif /* CONFIG_X86_FRED */

#endif /* !__ASSEMBLY__ */



#endif /* ASM_X86_FRED_H */