xref: /linux/arch/powerpc/include/asm/module.h (revision c906d2c74e0bb9059fbf43e21f8a962986eb21e2)
1 #ifndef _ASM_POWERPC_MODULE_H
2 #define _ASM_POWERPC_MODULE_H
3 #ifdef __KERNEL__
4 
5 /*
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/list.h>
13 #include <asm/bug.h>
14 #include <asm-generic/module.h>
15 
16 
17 #ifdef CC_USING_MPROFILE_KERNEL
18 #define MODULE_ARCH_VERMAGIC_FTRACE	"mprofile-kernel "
19 #else
20 #define MODULE_ARCH_VERMAGIC_FTRACE	""
21 #endif
22 
23 #ifdef CONFIG_RELOCATABLE
24 #define MODULE_ARCH_VERMAGIC_RELOCATABLE	"relocatable "
25 #else
26 #define MODULE_ARCH_VERMAGIC_RELOCATABLE	""
27 #endif
28 
29 #define MODULE_ARCH_VERMAGIC MODULE_ARCH_VERMAGIC_FTRACE MODULE_ARCH_VERMAGIC_RELOCATABLE
30 
31 #ifndef __powerpc64__
32 /*
33  * Thanks to Paul M for explaining this.
34  *
35  * PPC can only do rel jumps += 32MB, and often the kernel and other
36  * modules are further away than this.  So, we jump to a table of
37  * trampolines attached to the module (the Procedure Linkage Table)
38  * whenever that happens.
39  */
40 
41 struct ppc_plt_entry {
42 	/* 16 byte jump instruction sequence (4 instructions) */
43 	unsigned int jump[4];
44 };
45 #endif	/* __powerpc64__ */
46 
47 
48 struct mod_arch_specific {
49 #ifdef __powerpc64__
50 	unsigned int stubs_section;	/* Index of stubs section in module */
51 	unsigned int toc_section;	/* What section is the TOC? */
52 	bool toc_fixed;			/* Have we fixed up .TOC.? */
53 #ifdef CONFIG_DYNAMIC_FTRACE
54 	unsigned long toc;
55 	unsigned long tramp;
56 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
57 	unsigned long tramp_regs;
58 #endif
59 #endif
60 
61 	/* For module function descriptor dereference */
62 	unsigned long start_opd;
63 	unsigned long end_opd;
64 #else /* powerpc64 */
65 	/* Indices of PLT sections within module. */
66 	unsigned int core_plt_section;
67 	unsigned int init_plt_section;
68 #ifdef CONFIG_DYNAMIC_FTRACE
69 	unsigned long tramp;
70 #endif
71 #endif /* powerpc64 */
72 
73 	/* List of BUG addresses, source line numbers and filenames */
74 	struct list_head bug_list;
75 	struct bug_entry *bug_table;
76 	unsigned int num_bugs;
77 };
78 
79 /*
80  * Select ELF headers.
81  * Make empty section for module_frob_arch_sections to expand.
82  */
83 
84 #ifdef __powerpc64__
85 #    ifdef MODULE
86 	asm(".section .stubs,\"ax\",@nobits; .align 3; .previous");
87 #    endif
88 #else
89 #    ifdef MODULE
90 	asm(".section .plt,\"ax\",@nobits; .align 3; .previous");
91 	asm(".section .init.plt,\"ax\",@nobits; .align 3; .previous");
92 #    endif	/* MODULE */
93 #endif
94 
95 #ifdef CONFIG_DYNAMIC_FTRACE
96 #    ifdef MODULE
97 	asm(".section .ftrace.tramp,\"ax\",@nobits; .align 3; .previous");
98 #    endif	/* MODULE */
99 #endif
100 
101 int module_trampoline_target(struct module *mod, unsigned long trampoline,
102 			     unsigned long *target);
103 
104 #ifdef CONFIG_DYNAMIC_FTRACE
105 int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs);
106 #else
107 static inline int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs)
108 {
109 	return 0;
110 }
111 #endif
112 
113 #endif /* __KERNEL__ */
114 #endif	/* _ASM_POWERPC_MODULE_H */
115