~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/arch/powerpc/include/asm/code-patching.h

Version: ~ [ linux-4.20-rc3 ] ~ [ linux-4.19.2 ] ~ [ linux-4.18.19 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.81 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.137 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.163 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.125 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.60 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.31.14 ] ~ [ linux-2.6.30.10 ] ~ [ linux-2.6.29.6 ] ~ [ linux-2.6.28.10 ] ~ [ linux-2.6.27.62 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 #include <asm/ppc-opcode.h>
 15 #include <linux/string.h>
 16 #include <linux/kallsyms.h>
 17 #include <asm/asm-compat.h>
 18 
 19 /* Flags for create_branch:
 20  * "b"   == create_branch(addr, target, 0);
 21  * "ba"  == create_branch(addr, target, BRANCH_ABSOLUTE);
 22  * "bl"  == create_branch(addr, target, BRANCH_SET_LINK);
 23  * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK);
 24  */
 25 #define BRANCH_SET_LINK 0x1
 26 #define BRANCH_ABSOLUTE 0x2
 27 
 28 bool is_offset_in_branch_range(long offset);
 29 unsigned int create_branch(const unsigned int *addr,
 30                            unsigned long target, int flags);
 31 unsigned int create_cond_branch(const unsigned int *addr,
 32                                 unsigned long target, int flags);
 33 int patch_branch(unsigned int *addr, unsigned long target, int flags);
 34 int patch_instruction(unsigned int *addr, unsigned int instr);
 35 int raw_patch_instruction(unsigned int *addr, unsigned int instr);
 36 int patch_instruction_site(s32 *addr, unsigned int instr);
 37 int patch_branch_site(s32 *site, unsigned long target, int flags);
 38 
 39 static inline unsigned long patch_site_addr(s32 *site)
 40 {
 41         return (unsigned long)site + *site;
 42 }
 43 
 44 int instr_is_relative_branch(unsigned int instr);
 45 int instr_is_relative_link_branch(unsigned int instr);
 46 int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr);
 47 unsigned long branch_target(const unsigned int *instr);
 48 unsigned int translate_branch(const unsigned int *dest,
 49                               const unsigned int *src);
 50 extern bool is_conditional_branch(unsigned int instr);
 51 #ifdef CONFIG_PPC_BOOK3E_64
 52 void __patch_exception(int exc, unsigned long addr);
 53 #define patch_exception(exc, name) do { \
 54         extern unsigned int name; \
 55         __patch_exception((exc), (unsigned long)&name); \
 56 } while (0)
 57 #endif
 58 
 59 #define OP_RT_RA_MASK   0xffff0000UL
 60 #define LIS_R2          0x3c020000UL
 61 #define ADDIS_R2_R12    0x3c4c0000UL
 62 #define ADDI_R2_R2      0x38420000UL
 63 
 64 static inline unsigned long ppc_function_entry(void *func)
 65 {
 66 #ifdef PPC64_ELF_ABI_v2
 67         u32 *insn = func;
 68 
 69         /*
 70          * A PPC64 ABIv2 function may have a local and a global entry
 71          * point. We need to use the local entry point when patching
 72          * functions, so identify and step over the global entry point
 73          * sequence.
 74          *
 75          * The global entry point sequence is always of the form:
 76          *
 77          * addis r2,r12,XXXX
 78          * addi  r2,r2,XXXX
 79          *
 80          * A linker optimisation may convert the addis to lis:
 81          *
 82          * lis   r2,XXXX
 83          * addi  r2,r2,XXXX
 84          */
 85         if ((((*insn & OP_RT_RA_MASK) == ADDIS_R2_R12) ||
 86              ((*insn & OP_RT_RA_MASK) == LIS_R2)) &&
 87             ((*(insn+1) & OP_RT_RA_MASK) == ADDI_R2_R2))
 88                 return (unsigned long)(insn + 2);
 89         else
 90                 return (unsigned long)func;
 91 #elif defined(PPC64_ELF_ABI_v1)
 92         /*
 93          * On PPC64 ABIv1 the function pointer actually points to the
 94          * function's descriptor. The first entry in the descriptor is the
 95          * address of the function text.
 96          */
 97         return ((func_descr_t *)func)->entry;
 98 #else
 99         return (unsigned long)func;
100 #endif
101 }
102 
103 static inline unsigned long ppc_global_function_entry(void *func)
104 {
105 #ifdef PPC64_ELF_ABI_v2
106         /* PPC64 ABIv2 the global entry point is at the address */
107         return (unsigned long)func;
108 #else
109         /* All other cases there is no change vs ppc_function_entry() */
110         return ppc_function_entry(func);
111 #endif
112 }
113 
114 /*
115  * Wrapper around kallsyms_lookup() to return function entry address:
116  * - For ABIv1, we lookup the dot variant.
117  * - For ABIv2, we return the local entry point.
118  */
119 static inline unsigned long ppc_kallsyms_lookup_name(const char *name)
120 {
121         unsigned long addr;
122 #ifdef PPC64_ELF_ABI_v1
123         /* check for dot variant */
124         char dot_name[1 + KSYM_NAME_LEN];
125         bool dot_appended = false;
126 
127         if (strnlen(name, KSYM_NAME_LEN) >= KSYM_NAME_LEN)
128                 return 0;
129 
130         if (name[0] != '.') {
131                 dot_name[0] = '.';
132                 dot_name[1] = '\0';
133                 strlcat(dot_name, name, sizeof(dot_name));
134                 dot_appended = true;
135         } else {
136                 dot_name[0] = '\0';
137                 strlcat(dot_name, name, sizeof(dot_name));
138         }
139         addr = kallsyms_lookup_name(dot_name);
140         if (!addr && dot_appended)
141                 /* Let's try the original non-dot symbol lookup */
142                 addr = kallsyms_lookup_name(name);
143 #elif defined(PPC64_ELF_ABI_v2)
144         addr = kallsyms_lookup_name(name);
145         if (addr)
146                 addr = ppc_function_entry((void *)addr);
147 #else
148         addr = kallsyms_lookup_name(name);
149 #endif
150         return addr;
151 }
152 
153 #ifdef CONFIG_PPC64
154 /*
155  * Some instruction encodings commonly used in dynamic ftracing
156  * and function live patching.
157  */
158 
159 /* This must match the definition of STK_GOT in <asm/ppc_asm.h> */
160 #ifdef PPC64_ELF_ABI_v2
161 #define R2_STACK_OFFSET         24
162 #else
163 #define R2_STACK_OFFSET         40
164 #endif
165 
166 #define PPC_INST_LD_TOC         (PPC_INST_LD  | ___PPC_RT(__REG_R2) | \
167                                  ___PPC_RA(__REG_R1) | R2_STACK_OFFSET)
168 
169 /* usually preceded by a mflr r0 */
170 #define PPC_INST_STD_LR         (PPC_INST_STD | ___PPC_RS(__REG_R0) | \
171                                  ___PPC_RA(__REG_R1) | PPC_LR_STKOFF)
172 #endif /* CONFIG_PPC64 */
173 
174 #endif /* _ASM_POWERPC_CODE_PATCHING_H */
175 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp