xref: /linux/arch/powerpc/include/asm/module.h (revision 69bfec7548f4c1595bac0e3ddfc0458a5af31f4c)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _ASM_POWERPC_MODULE_H
3 #define _ASM_POWERPC_MODULE_H
4 #ifdef __KERNEL__
5 
6 #include <linux/list.h>
7 #include <asm/bug.h>
8 #include <asm-generic/module.h>
9 
10 #ifndef __powerpc64__
11 /*
12  * Thanks to Paul M for explaining this.
13  *
14  * PPC can only do rel jumps += 32MB, and often the kernel and other
15  * modules are further away than this.  So, we jump to a table of
16  * trampolines attached to the module (the Procedure Linkage Table)
17  * whenever that happens.
18  */
19 
20 struct ppc_plt_entry {
21 	/* 16 byte jump instruction sequence (4 instructions) */
22 	unsigned int jump[4];
23 };
24 #endif	/* __powerpc64__ */
25 
26 
27 struct mod_arch_specific {
28 #ifdef __powerpc64__
29 	unsigned int stubs_section;	/* Index of stubs section in module */
30 	unsigned int toc_section;	/* What section is the TOC? */
31 	bool toc_fixed;			/* Have we fixed up .TOC.? */
32 
33 	/* For module function descriptor dereference */
34 	unsigned long start_opd;
35 	unsigned long end_opd;
36 #else /* powerpc64 */
37 	/* Indices of PLT sections within module. */
38 	unsigned int core_plt_section;
39 	unsigned int init_plt_section;
40 #endif /* powerpc64 */
41 
42 #ifdef CONFIG_DYNAMIC_FTRACE
43 	unsigned long tramp;
44 	unsigned long tramp_regs;
45 #endif
46 
47 	/* List of BUG addresses, source line numbers and filenames */
48 	struct list_head bug_list;
49 	struct bug_entry *bug_table;
50 	unsigned int num_bugs;
51 };
52 
53 /*
54  * Select ELF headers.
55  * Make empty section for module_frob_arch_sections to expand.
56  */
57 
58 #ifdef __powerpc64__
59 #    ifdef MODULE
60 	asm(".section .stubs,\"ax\",@nobits; .align 3; .previous");
61 #    endif
62 #else
63 #    ifdef MODULE
64 	asm(".section .plt,\"ax\",@nobits; .align 3; .previous");
65 	asm(".section .init.plt,\"ax\",@nobits; .align 3; .previous");
66 #    endif	/* MODULE */
67 #endif
68 
69 #ifdef CONFIG_DYNAMIC_FTRACE
70 #    ifdef MODULE
71 	asm(".section .ftrace.tramp,\"ax\",@nobits; .align 3; .previous");
72 #    endif	/* MODULE */
73 
74 int module_trampoline_target(struct module *mod, unsigned long trampoline,
75 			     unsigned long *target);
76 int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs);
77 #else
78 static inline int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs)
79 {
80 	return 0;
81 }
82 #endif
83 
84 #endif /* __KERNEL__ */
85 #endif	/* _ASM_POWERPC_MODULE_H */
86