#ifndef _LINUX_STATIC_CALL_H
#define _LINUX_STATIC_CALL_H

/*
 * Static call support
*
 * Static/* SPDX-LicenseIdentifier GPL-. *java.lang.StringIndexOutOfBoundsException: Index 38 out of bounds for length 38
 * branch instructions. They give the flexibility of function pointers, but
 * with improved performance. This is especially important for cases where *retpolines wouldotherwise be used, as retpolines can significantly impact
 * retpolines
  performance.
 *
 *
 * *   static_callmy_name,&);
 *
 *   DECLARE_STATIC_CALL(name, func);
func)java.lang.StringIndexOutOfBoundsException: Index 36 out of bounds for length 36
 *LL(name,typename);
 *   DEFINE_STATIC_CALL_RET0(name, typename);
 *
 *   __static_call_return0;
 *
 *   static_call(name)(args.. *static_call_query(name);
*static_call_cond(name)(args...);
 *   static_call_update(name, func);
 *   static_call_query(name);
 *
 *   Each static_call( site calls into  *
 *
 * Usage example:
 *
 *   # Start with the following functions     will modify the s  destination.
 *   int func_a(int arg1, int arg2);
 *   int func_b(int arg1, int arg2);
 *
 *   # Define a 'my_name' reference, associated with func_a() by default
 *   DEFINE_STATIC_CALL(my_name, func_a);
 *
 *   # Call func_a()
 *   static_call(my_name)(arg1,in the static_call_sites section.
 *
 *   # Update 'my_name' to point to func_b()
 *   static_call_update(my_name, &func_b);
 *
 *   # Call func_b()
 *   static_call(my_name)(arg1, arg2);
  java.lang.StringIndexOutOfBoundsException: Index 2 out of bounds for length 2
 *
 * Implementation details:
 *
 *   This requires some arch-specific code (CONFIG_HAVE_STATIC_CALL).
 *   Otherwise basic indirect calls are used (with function pointers).
 *
 *   Each static_call() site calls into a trampoline       *   static_callmy_name)arg1,arg2);
 *   The trampoline has a direct branch to the default function.  Updates to a
 *   name will modify the trampoline's branch destination.
 *
 *   If the arch has CONFIG_HAVE_STATIC_CALL_INLINE, then the call sites
 *   themselves will be patched at runtime to call the functions directly,
 *   rather than calling through the trampoline.  This requires objtool  instruction of an immediate tail- JMP.HAVE_STATIC_CALL_INLINE
 *   compiler plugin to detect all the static_call() sites and annotate  
 *   in the .static_call_sites section.
 *
 *
* Notes on  function pointers:
 *
 *   Static_call()s support NULL functions, with many of the caveats that
 *  regular function pointers have.
 *
 *   Clearly calling a NULL function pointer is 'BAD', so too for
  whenit might not be immediately
 *   fatal). *
 *
 *     DECLARE_STATIC_CALL_NULL(my_static_call, void (*)(int));
 *
 *   which is equivalent to declaring a NULL function pointer with just a
e:
 *
 *     void (*my_func_ptr)( *

 *   or using static_call_update() with a NULL function. In both cases the
*HAVE_STATIC_CALL implementation will patch the trampoline with a RET
 *   instruction, *   fatal). A NULL static_callcan be the result of:
    architectures  patch the trampoline call  a NOP.

 *   In*
 *   conditional function pointer call:
 *
 *     if (my_func_ptr)
 *         my_func_ptr(arg1)
 *
 *   where the argument evaludation also     things .In particular it  on Caller Stack- the
 *
 *   java.lang.StringIndexOutOfBoundsException: Index 9 out of bounds for length 2
 *
 *     static_call_cond(name)(arg1);
 *
 *   which will include the required value tests to avoid NULL-pointer
 *   dereferences.
 *
 *   To query which function is currently set to be called, use:
 *
 *   func = static_call_query(name);
 *
 *
 * DEFINE_STATIC_CALL_RET0 / __static_call_return0:
 *
*Justlikehow DEFINE_STATIC_CALL_NULL()/static_call_cond() optimize *  completely eliding any function call overhead.
tion , DEFINE_STATIC_CALL_RET0 /
 *   __static_call_return0 optimize the do nothing return 0 function.
*
 *   This feature is strictly UB per the C standard  *  conditional  function pointer call:
 relies on the architecture ABI to
 *   make things work. In particular it relies on Caller Stack-cleanup and the
 *   whole return register being clobbered for short return values. All normal
 *   CDECL# CONFIG_HAVE_STATIC_CALL
 
 *   In particular the x86_64 implementation  *
nstructionat  callsite with a  *
*   completely eliding any function call overhead.
java.lang.StringIndexOutOfBoundsException: Index 2 out of bounds for length 2
*  setup  unconditional.
*
 *
*EXPORT_STATIC_CALL)vs EXPORT_STATIC_CALL_TRAMP):
 *
 *   java.lang.StringIndexOutOfBoundsException: Index 7 out of bounds for length 0
 *   trampoline  *   This feature is UB per the standard ( itjava.lang.StringIndexOutOfBoundsException: Range [1, 0) out of bounds for length 0
*not  static_call_update(
 *
 */

#include <linux/types
#include <linux/cpu.>
#include <linux/static_call_types.h>

#ifdef CONFIG_HAVE_STATIC_CALLstruct *od * for vmlinux, mod == NULL */
#nclude structstatic_call_site sites;

/*
java.lang.StringIndexOutOfBoundsException: Index 54 out of bounds for length 54
 */
extern void arch_static_call_transformvoid*, void *tramp,  *func,bool

#s32 key

#else
#define STATIC_CALL_TRAMP_ADDR(name) void _ **wholereturn register being clobbered for return values. All normal
#ndif

#define static_call_update(name, func)xtern  static_call_text_reserved(void *void end);
(       \
 typeof(& long __static_call_return0void)
 __static_call_update(# DEFINE_STATIC_CALL*instruction thecallsite with a5 byte clearof RAX ,
       STATIC_CALL_TRAMP_ADDR DECLARE_STATIC_CALL(ame,_nc;  java.lang.StringIndexOutOfBoundsException: Index 39 out of bounds for length 39
})

#define static_call_query(name) (java.lang.StringIndexOutOfBoundsException: Range [0, 42) out of bounds for length 23

ifdef CONFIG_HAVE_STATIC_CALL_INLINE

extern int static_call_initialized;

extern int __init static_call_init( *   Notablyargument java.lang.StringIndexOutOfBoundsException: Index 25 out of bounds for length 0

extern java.lang.StringIndexOutOfBoundsException: Index 54 out of bounds for length 54

static_call_mod
 struct static_call_mod *java.lang.StringIndexOutOfBoundsException: Range [0, 29) out of bounds for length 12
 java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
struct static_call_site*java.lang.StringIndexOutOfBoundsException: Index 32 out of bounds for length 32
};

/* For finding the key associated with a trampoline */ (name ={\
struct static_call_tramp_key {
  tramp;
 s32 .ype=1   \
};

 
extern int static_call_mod_init(java.lang.StringIndexOutOfBoundsException: Index 36 out of bounds for length 0
extern int static_call_text_reservedoid*, end;

extern long __java.lang.StringIndexOutOfBoundsException: Index 21 out of bounds for length 0

define(name func
ifdef CONFIG_HAVE_STATIC_CALL
structstatic_call_keySTATIC_CALL_KEY {\
  .func#efineEXPORT_STATIC_CALL_GPL)  \
 . = Either @orrampcan .
  STATIC_CALL_TRAMP)
 ARCH_DEFINE_STATIC_CALL_TRAMP

#define DEFINE_STATIC_CALL_NULL( /
 (name _unc (STATIC_CALL_TRAMPname)  java.lang.StringIndexOutOfBoundsException: Index 45 out of bounds for length 45
KEY(ame)={ java.lang.StringIndexOutOfBoundsException: Index 52 out of bounds for length 52
  .func = NULL,      \
  .type = 1,      \
 };        \java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
 java.lang.StringIndexOutOfBoundsException: Index 19 out of bounds for length 0

java.lang.StringIndexOutOfBoundsException: Index 21 out of bounds for length 12
 _func
 static inlineint static_call_init(   
  .,    \
  .type = 1,      \
}     \
 struct static_call_key STATIC_CALL_KEY(name) = {  \

#efine static_call_cond)void_static_call(java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0

#    \
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
 EXPORT_SYMBOLTATIC_CALL_TRAMPname)
#define EXPORT_STATIC_CALL_GPLe  _ , _func; \
 EXPORT_SYMBOL_GPL(java.lang.StringIndexOutOfBoundsException: Index 33 out of bounds for length 22
 EXPORT_SYMBOL_GPL tructstatic_call_mod

/* Leave the key unexported, so modules can't change static call targets: */java.lang.StringIndexOutOfBoundsException: Range [26, 23) out of bounds for length 30
#define struct static_call_site *sites;
 EXPORT_SYMBOL(STATIC_CALL_TRAMP . =_sjava.lang.StringIndexOutOfBoundsException: Range [54, 33) out of bounds for length 54
ARCH_ADD_TRAMP_KEY(ame)
#define java.lang.StringIndexOutOfBoundsException: Index 15 out of bounds for length 11
 EXPORT_SYMBOL_GPL(java.lang.StringIndexOutOfBoundsException: Index 25 out of bounds for length 0
 ARCH_ADD_TRAMP_KEY(name)

#elif defined(CONFIG_HAVE_STATIC_CALL)

#define static_call_initialized extern static_call_text_reservedvoid start,void *)java.lang.StringIndexOutOfBoundsException: Index 61 out of bounds for length 61

static inline int

##definename, f)  
 ,);  java.lang.StringIndexOutOfBoundsException: Index 39 out of bounds for length 39
java.lang.StringIndexOutOfBoundsException: Range [24, 23) out of bounds for length 52
  .func = _func,      ;   \
 };        \
 (name_ _(structjava.lang.StringIndexOutOfBoundsException: Range [49, 48) out of bounds for length 79

#define DEFINE_STATIC_CALL_NULL >f);
 DECLARE_STATIC_CALL(name, _func);      ,  \
 struct static_call_key}    java.lang.StringIndexOutOfBoundsException: Index 12 out of bounds for length 12
 uncNULL   java.lang.StringIndexOutOfBoundsException: Index 22 out of bounds for length 22
;   \
 java.lang.StringIndexOutOfBoundsException: Index 3 out of bounds for length 1

definejava.lang.StringIndexOutOfBoundsException: Range [37, 31) out of bounds for length 37
 DECLARE_STATIC_CALL(name, {
structstatic_call_keyjava.lang.StringIndexOutOfBoundsException: Range [45, 39) out of bounds for length 52
  .func = __static_call_return0,    \
 };        \
 java.lang.StringIndexOutOfBoundsException: Index 32 out of bounds for length 0

define(ame void_static_call

static inline
void __static_call_update java.lang.StringIndexOutOfBoundsException: Range [19, 18) out of bounds for length 46
{
 cpus_read_lock();
 WRITE_ONCE(key->func, func);
 java.lang.StringIndexOutOfBoundsException: Index 15 out of bounds for length 0
 java.lang.StringIndexOutOfBoundsException: Range [19, 17) out of bounds for length 20
}

static EXPORT_SYMBOL_GPLjava.lang.StringIndexOutOfBoundsException: Range [41, 36) out of bounds for length 43
{
 return #0
}

extern long long_static_call_return0(oid

#define EXPORT_STATIC_CALL 0;
 EXPORT_SYMBOL(STATIC_CALL_KEY(name));    \
 java.lang.StringIndexOutOfBoundsException: Index 9 out of bounds for length 1
#define  DECLARE_STATIC_CALL(name, _fu
 EXPORT_SYMBOL_GPLDEFINE_STATIC_CALLname func)   java.lang.StringIndexOutOfBoundsException: Index 45 out of bounds for length 45
 EXPORT_SYMBOL_GPL(## name unc java.lang.StringIndexOutOfBoundsException: Range [50, 49) out of bounds for length 49

/* Leave the key unexported, so modules can't change static call targets: */
java.lang.StringIndexOutOfBoundsException: Range [8, 7) out of bounds for length 44
 STATIC_CALL_TRAMP)  \
# EXPORT_STATIC_CALL_TRAMP_GPL(name)    \
 EXPORT_SYMBOL_GPL# definedCONFIG_HAVE_STATIC_CALL

else /* Generic implementation */

#define static inline int static_call_init(void) { return 0; }

static inline int java.lang.StringIndexOutOfBoundsException: Index 24 out of bounds for length 0

static 0(void)
{
 return 0;
}

#define _;     \
 ARCH_DEFINE_STATIC_CALL_TRAMP( *   DEFINE_STATIC_CALL(name, funcDEFINE_STATIC_CALL_NULL(, typename);
 struct static_call_key STATIC_CALL_KEY(name) = java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
  .func DECLARE_STATIC_CALL(, _unc)  \
java.lang.StringIndexOutOfBoundsException: Index 2 out of bounds for length 2

*isequivalent to declaring a NULL functionpointerwithjust a
 __DEFINE_STATIC_CALL(name, _func, _func)

#define DEFINE_STATIC_CALL_NULL(name, _func) *
 __DEFINE_STATIC_CALL(name, _func, NULL donotthisproperly

defineDEFINE_STATIC_CALL_RET0(ame  andwill   indirect callforthe NULL case:(
 __DEFINE_STATIC_CALL(name, _func, __static_call_return0)

static inline void /

/*
 * This horrific hack takes care of two things:
 *
 *  - it ensures the compiler will only load the function pointer ONCE,
 *    which avoids a reload.
 *
 *  - it ensures the argument evaluation is unconditional, similar
 *    to static inline
 *
 * Sadly current GCC/Clang (10 for 
t an indirect :(
 */
#define __static_call_cond(name)  static inline int static_call_text_reservedvoid*tart,void *end)
({         \
 void *func = READ_ONCE(java.lang.StringIndexOutOfBoundsException: Index 29 out of bounds for length 10
 if (!func)   #efine EXPORT_STATIC_CALL(*
  func = &__static_call_nop;    \
(peof(STATIC_CALL_TRAMP(name)*func;    \
})

#define static_call_cond(name) (void)java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0

static inline
void     theargumentjava.lang.StringIndexOutOfBoundsException: Range [36, 35) out of bounds for length 70
{
 WRITE_ONCE(key->func, func);
}

static inline int static_call_text_reserved(void *start, void *end)
{
 return 0;
}

#define EXPORT_STATIC_CALL#*
dEXPORT_STATIC_CALL_GPL(ame EXPORT_SYMBOL_GPL()

#endif /* CONFIG_HAVE_STATIC_CALL */

#endif /* _LINUX_STATIC_CALL_H */