1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_SECTIONS_H
3 #define _ASM_POWERPC_SECTIONS_H
4 #ifdef __KERNEL__
5 
6 #include <linux/elf.h>
7 #include <linux/uaccess.h>
8 
9 #define arch_is_kernel_initmem_freed arch_is_kernel_initmem_freed
10 
11 #include <asm-generic/sections.h>
12 
13 extern bool init_mem_is_free;
14 
15 static inline int arch_is_kernel_initmem_freed(unsigned long addr)
16 {
17 	if (!init_mem_is_free)
18 		return 0;
19 
20 	return addr >= (unsigned long)__init_begin &&
21 		addr < (unsigned long)__init_end;
22 }
23 
24 extern char __head_end[];
25 
26 #ifdef __powerpc64__
27 
28 extern char __start_interrupts[];
29 extern char __end_interrupts[];
30 
31 extern char __prom_init_toc_start[];
32 extern char __prom_init_toc_end[];
33 
34 #ifdef CONFIG_PPC_POWERNV
35 extern char start_real_trampolines[];
36 extern char end_real_trampolines[];
37 extern char start_virt_trampolines[];
38 extern char end_virt_trampolines[];
39 #endif
40 
41 static inline int in_kernel_text(unsigned long addr)
42 {
43 	if (addr >= (unsigned long)_stext && addr < (unsigned long)__init_end)
44 		return 1;
45 
46 	return 0;
47 }
48 
49 static inline unsigned long kernel_toc_addr(void)
50 {
51 	/* Defined by the linker, see vmlinux.lds.S */
52 	extern unsigned long __toc_start;
53 
54 	/*
55 	 * The TOC register (r2) points 32kB into the TOC, so that 64kB of
56 	 * the TOC can be addressed using a single machine instruction.
57 	 */
58 	return (unsigned long)(&__toc_start) + 0x8000UL;
59 }
60 
61 static inline int overlaps_interrupt_vector_text(unsigned long start,
62 							unsigned long end)
63 {
64 	unsigned long real_start, real_end;
65 	real_start = __start_interrupts - _stext;
66 	real_end = __end_interrupts - _stext;
67 
68 	return start < (unsigned long)__va(real_end) &&
69 		(unsigned long)__va(real_start) < end;
70 }
71 
72 static inline int overlaps_kernel_text(unsigned long start, unsigned long end)
73 {
74 	return start < (unsigned long)__init_end &&
75 		(unsigned long)_stext < end;
76 }
77 
78 #ifdef PPC64_ELF_ABI_v1
79 
80 #define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
81 
82 #undef dereference_function_descriptor
83 static inline void *dereference_function_descriptor(void *ptr)
84 {
85 	struct ppc64_opd_entry *desc = ptr;
86 	void *p;
87 
88 	if (!get_kernel_nofault(p, (void *)&desc->funcaddr))
89 		ptr = p;
90 	return ptr;
91 }
92 
93 #undef dereference_kernel_function_descriptor
94 static inline void *dereference_kernel_function_descriptor(void *ptr)
95 {
96 	if (ptr < (void *)__start_opd || ptr >= (void *)__end_opd)
97 		return ptr;
98 
99 	return dereference_function_descriptor(ptr);
100 }
101 #endif /* PPC64_ELF_ABI_v1 */
102 
103 #endif
104 
105 #endif /* __KERNEL__ */
106 #endif	/* _ASM_POWERPC_SECTIONS_H */
107