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  9   ˆl–Ðz¾””ÔD¨ 	Å íÆEq©‹FÿÀƒh¹a–Ðz¾””ÔD¨ 	Å íÆEq©‹FÿÃ      MAJOR=7
MINOR=68
DEVNAME=vcsu4
  +   	ˆl–Ü4ý( ©³( 	Å€fàD¦-ÿÂ„m‰Ï_†I|¥+ÀÅ <¦    	/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_ALTERNATIVE_H
#define _ASM_X86_ALTERNATIVE_H

#include <linux/types.h>
#include <linux/stringify.h>
#include <linux/objtool.h>
#include <asm/asm.h>

#define ALT_FLAGS_SHIFT		16

#define ALT_FLAG_NOT		(1 << 0)
#define ALT_NOT(feature)	((ALT_FLAG_NOT << ALT_FLAGS_SHIFT) | (feature))
#define ALT_FLAG_DIRECT_CALL	(1 << 1)
#define ALT_DIRECT_CALL(feature) ((ALT_FLAG_DIRECT_CALL << ALT_FLAGS_SHIFT) | (feature))
#define ALT_CALL_ALWAYS		ALT_DIRECT_CALL(X86_FEATURE_ALWAYS)

#ifndef __ASSEMBLY__

#include <linux/stddef.h>

/*
 * Alternative inline assembly for SMP.
 *
 * The LOCK_PREFIX macro defined here replaces the LOCK and
 * LOCK_PREFIX macros used everywhere in the source tree.
 *
 * SMP alternatives use the same data structures as the other
 * alternatives and the X86_FEATURE_UP flag to indicate the case of a
 * UP system running a SMP kernel.  The existing apply_alternatives()
 * works fine for patching a SMP kernel for UP.
 *
 * The SMP alternative tables can be kept after boot and contain both
 * UP and SMP versions of the instructions to allow switching back to
 * SMP at runtime, when hotplugging in a new CPU, which is especially
 * useful in virtualized environments.
 *
 * The very common lock prefix is handled as special case in a
 * separate table which is a pure address list without replacement ptr
 * and size information.  That keeps the table sizes small.
 */

#ifdef CONFIG_SMP
#define LOCK_PREFIX_HERE \
		".pushsection .smp_locks,\"a\"\n"	\
		".balign 4\n"				\
		".long 671f - .\n" /* offset */		\
		".popsection\n"				\
		"671:"

#define LOCK_PREFIX LOCK_PREFIX_HERE "\n\tlock; "

#else /* ! CONFIG_SMP */
#define LOCK_PREFIX_HERE ""
#define LOCK_PREFIX ""
#endif

/*
 * The patching flags are part of the upper bits of the @ft_flags parameter when
 * specifying them. The split is currently like this:
 *
 * [31... flags ...16][15... CPUID feature bit ...0]
 *
 * but since this is all hidden in the macros argument being split, those fields can be
 * extended in the future to fit in a u64 or however the need arises.
 */
struct alt_instr {
	s32 instr_offset;	/* original instruction */
	s32 repl_offset;	/* offset to replacement instruction */

	union {
		struct {
			u32 cpuid: 16;	/* CPUID bit set for replacement */
			u32 flags: 16;	/* patching control flags */
		};
		u32 ft_flags;
	};

	u8  instrlen;		/* length of original instruction */
	u8  replacementlen;	/* length of new instruction */
} __packed;

extern struct alt_instr __alt_instructions[], __alt_instructions_end[];

/*
 * Debug flag that can be tested to see whether alternative
 * instructions were patched in already:
 */
extern int alternatives_patched;

extern void alternative_instructions(void);
extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end);
extern void apply_retpolines(s32 *start, s32 *end);
extern void apply_returns(s32 *start, s32 *end);
extern void apply_seal_endbr(s32 *start, s32 *end);
extern void apply_fineibt(s32 *start_retpoline, s32 *end_retpoine,
			  s32 *start_cfi, s32 *end_cfi);

struct module;

struct callthunk_sites {
	s32				*call_start, *call_end;
	struct alt_instr		*alt_start, *alt_end;
};

#ifdef CONFIG_CALL_THUNKS
extern void callthunks_patch_builtin_calls(void);
extern void callthunks_patch_module_calls(struct callthunk_sites *sites,
					  struct module *mod);
extern void *callthunks_translate_call_dest(void *dest);
extern int x86_call_depth_emit_accounting(u8 **pprog, void *func, void *ip);
#else
static __always_inline void callthunks_patch_builtin_calls(void) {}
static __always_inline void
callthunks_patch_module_calls(struct callthunk_sites *sites,
			      struct module *mod) {}
static __always_inline void *callthunks_translate_call_dest(void *dest)
{
	return dest;
}
static __always_inline int x86_call_depth_emit_accounting(u8 **pprog,
							  void *func, void *ip)
{
	return