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
   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 unsigned long kernel_toc_addr(void)
  42 {
  43         /* Defined by the linker, see vmlinux.lds.S */
  44         extern unsigned long __toc_start;
  45
  46         /*
  47          * The TOC register (r2) points 32kB into the TOC, so that 64kB of
  48          * the TOC can be addressed using a single machine instruction.
  49          */
  50         return (unsigned long)(&__toc_start) + 0x8000UL;
  51 }
  52
  53 static inline int overlaps_interrupt_vector_text(unsigned long start,
  54                                                         unsigned long end)
  55 {
  56         unsigned long real_start, real_end;
  57         real_start = __start_interrupts - _stext;
  58         real_end = __end_interrupts - _stext;
  59
  60         return start < (unsigned long)__va(real_end) &&
  61                 (unsigned long)__va(real_start) < end;
  62 }
  63
  64 static inline int overlaps_kernel_text(unsigned long start, unsigned long end)
  65 {
  66         return start < (unsigned long)__init_end &&
  67                 (unsigned long)_stext < end;
  68 }
  69
  70 #ifdef PPC64_ELF_ABI_v1
  71
  72 #define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
  73
  74 #undef dereference_function_descriptor
  75 static inline void *dereference_function_descriptor(void *ptr)
  76 {
  77         struct ppc64_opd_entry *desc = ptr;
  78         void *p;
  79
  80         if (!get_kernel_nofault(p, (void *)&desc->funcaddr))
  81                 ptr = p;
  82         return ptr;
  83 }
  84
  85 #undef dereference_kernel_function_descriptor
  86 static inline void *dereference_kernel_function_descriptor(void *ptr)
  87 {
  88         if (ptr < (void *)__start_opd || ptr >= (void *)__end_opd)
  89                 return ptr;
  90
  91         return dereference_function_descriptor(ptr);
  92 }
  93 #endif /* PPC64_ELF_ABI_v1 */
  94
  95 #endif
  96
  97 #endif /* __KERNEL__ */
  98 #endif  /* _ASM_POWERPC_SECTIONS_H */