arch/powerpc/include/asm/sections.h

   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 #include <asm-generic/sections.h>
   9
  10 extern char __head_end[];
  11
  12 #ifdef __powerpc64__
  13
  14 extern char __start_interrupts[];
  15 extern char __end_interrupts[];
  16
  17 extern char __prom_init_toc_start[];
  18 extern char __prom_init_toc_end[];
  19
  20 static inline int in_kernel_text(unsigned long addr)
  21 {
  22         if (addr >= (unsigned long)_stext && addr < (unsigned long)__init_end)
  23                 return 1;
  24
  25         return 0;
  26 }
  27
  28 static inline unsigned long kernel_toc_addr(void)
  29 {
  30         /* Defined by the linker, see vmlinux.lds.S */
  31         extern unsigned long __toc_start;
  32
  33         /*
  34          * The TOC register (r2) points 32kB into the TOC, so that 64kB of
  35          * the TOC can be addressed using a single machine instruction.
  36          */
  37         return (unsigned long)(&__toc_start) + 0x8000UL;
  38 }
  39
  40 static inline int overlaps_interrupt_vector_text(unsigned long start,
  41                                                         unsigned long end)
  42 {
  43         unsigned long real_start, real_end;
  44         real_start = __start_interrupts - _stext;
  45         real_end = __end_interrupts - _stext;
  46
  47         return start < (unsigned long)__va(real_end) &&
  48                 (unsigned long)__va(real_start) < end;
  49 }
  50
  51 static inline int overlaps_kernel_text(unsigned long start, unsigned long end)
  52 {
  53         return start < (unsigned long)__init_end &&
  54                 (unsigned long)_stext < end;
  55 }
  56
  57 static inline int overlaps_kvm_tmp(unsigned long start, unsigned long end)
  58 {
  59 #ifdef CONFIG_KVM_GUEST
  60         extern char kvm_tmp[];
  61         return start < (unsigned long)kvm_tmp &&
  62                 (unsigned long)&kvm_tmp[1024 * 1024] < end;
  63 #else
  64         return 0;
  65 #endif
  66 }
  67
  68 #ifdef PPC64_ELF_ABI_v1
  69
  70 #define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
  71
  72 #undef dereference_function_descriptor
  73 static inline void *dereference_function_descriptor(void *ptr)
  74 {
  75         struct ppc64_opd_entry *desc = ptr;
  76         void *p;
  77
  78         if (!probe_kernel_address(&desc->funcaddr, p))
  79                 ptr = p;
  80         return ptr;
  81 }
  82
  83 #undef dereference_kernel_function_descriptor
  84 static inline void *dereference_kernel_function_descriptor(void *ptr)
  85 {
  86         if (ptr < (void *)__start_opd || ptr >= (void *)__end_opd)
  87                 return ptr;
  88
  89         return dereference_function_descriptor(ptr);
  90 }
  91 #endif /* PPC64_ELF_ABI_v1 */
  92
  93 #endif
  94
  95 #endif /* __KERNEL__ */
  96 #endif  /* _ASM_POWERPC_SECTIONS_H */