xref: /linux/arch/powerpc/include/asm/module.h (revision bfb921b2a9d5d1123d1d10b196a39db629ddef87)
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 #ifdef CONFIG_PPC_KERNEL_PCREL
31 	unsigned int got_section;	/* What section is the GOT? */
32 	unsigned int pcpu_section;	/* .data..percpu section */
33 #else
34 	unsigned int toc_section;	/* What section is the TOC? */
35 	bool toc_fixed;			/* Have we fixed up .TOC.? */
36 #endif
37 
38 	/* For module function descriptor dereference */
39 	unsigned long start_opd;
40 	unsigned long end_opd;
41 #else /* powerpc64 */
42 	/* Indices of PLT sections within module. */
43 	unsigned int core_plt_section;
44 	unsigned int init_plt_section;
45 #endif /* powerpc64 */
46 
47 #ifdef CONFIG_DYNAMIC_FTRACE
48 	unsigned long tramp;
49 	unsigned long tramp_regs;
50 #endif
51 };
52 
53 /*
54  * Select ELF headers.
55  * Make empty sections 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 #        ifdef CONFIG_PPC_KERNEL_PCREL
62 	    asm(".section .mygot,\"a\",@nobits; .align 3; .previous");
63 #        endif
64 #    endif
65 #else
66 #    ifdef MODULE
67 	asm(".section .plt,\"ax\",@nobits; .align 3; .previous");
68 	asm(".section .init.plt,\"ax\",@nobits; .align 3; .previous");
69 #    endif	/* MODULE */
70 #endif
71 
72 #ifdef CONFIG_DYNAMIC_FTRACE
73 int module_trampoline_target(struct module *mod, unsigned long trampoline,
74 			     unsigned long *target);
75 int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs);
76 #else
77 static inline int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs)
78 {
79 	return 0;
80 }
81 #endif
82 
83 #endif /* __KERNEL__ */
84 #endif	/* _ASM_POWERPC_MODULE_H */
85