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