]> Pileus Git - ~andy/linux/blob - include/asm-powerpc/code-patching.h
powerpc: Add ppc_function_entry() which gets the entry point for a function
[~andy/linux] / include / asm-powerpc / code-patching.h
1 #ifndef _ASM_POWERPC_CODE_PATCHING_H
2 #define _ASM_POWERPC_CODE_PATCHING_H
3
4 /*
5  * Copyright 2008, Michael Ellerman, IBM Corporation.
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; either version
10  * 2 of the License, or (at your option) any later version.
11  */
12
13 #include <asm/types.h>
14
15 /* Flags for create_branch:
16  * "b"   == create_branch(addr, target, 0);
17  * "ba"  == create_branch(addr, target, BRANCH_ABSOLUTE);
18  * "bl"  == create_branch(addr, target, BRANCH_SET_LINK);
19  * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK);
20  */
21 #define BRANCH_SET_LINK 0x1
22 #define BRANCH_ABSOLUTE 0x2
23
24 unsigned int create_branch(const unsigned int *addr,
25                            unsigned long target, int flags);
26 void patch_branch(unsigned int *addr, unsigned long target, int flags);
27 void patch_instruction(unsigned int *addr, unsigned int instr);
28
29 static inline unsigned long ppc_function_entry(void *func)
30 {
31 #ifdef CONFIG_PPC64
32         /*
33          * On PPC64 the function pointer actually points to the function's
34          * descriptor. The first entry in the descriptor is the address
35          * of the function text.
36          */
37         return ((func_descr_t *)func)->entry;
38 #else
39         return (unsigned long)func;
40 #endif
41 }
42
43 #endif /* _ASM_POWERPC_CODE_PATCHING_H */