root/arch/sparc/kernel/kstack.h

INCLUDED FROM

DEFINITIONS

1. kstack_valid
2. kstack_is_trap_frame
3. set_hardirq_stack
4. restore_hardirq_stack

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _KSTACK_H
   3 #define _KSTACK_H
   4 
   5 #include <linux/thread_info.h>
   6 #include <linux/sched.h>
   7 #include <asm/ptrace.h>
   8 #include <asm/irq.h>
   9 
  10 /* SP must be STACK_BIAS adjusted already.  */
  11 static inline bool kstack_valid(struct thread_info *tp, unsigned long sp)
  12 {
  13         unsigned long base = (unsigned long) tp;
  14 
  15         /* Stack pointer must be 16-byte aligned.  */
  16         if (sp & (16UL - 1))
  17                 return false;
  18 
  19         if (sp >= (base + sizeof(struct thread_info)) &&
  20             sp <= (base + THREAD_SIZE - sizeof(struct sparc_stackf)))
  21                 return true;
  22 
  23         if (hardirq_stack[tp->cpu]) {
  24                 base = (unsigned long) hardirq_stack[tp->cpu];
  25                 if (sp >= base &&
  26                     sp <= (base + THREAD_SIZE - sizeof(struct sparc_stackf)))
  27                         return true;
  28                 base = (unsigned long) softirq_stack[tp->cpu];
  29                 if (sp >= base &&
  30                     sp <= (base + THREAD_SIZE - sizeof(struct sparc_stackf)))
  31                         return true;
  32         }
  33         return false;
  34 }
  35 
  36 /* Does "regs" point to a valid pt_regs trap frame?  */
  37 static inline bool kstack_is_trap_frame(struct thread_info *tp, struct pt_regs *regs)
  38 {
  39         unsigned long base = (unsigned long) tp;
  40         unsigned long addr = (unsigned long) regs;
  41 
  42         if (addr >= base &&
  43             addr <= (base + THREAD_SIZE - sizeof(*regs)))
  44                 goto check_magic;
  45 
  46         if (hardirq_stack[tp->cpu]) {
  47                 base = (unsigned long) hardirq_stack[tp->cpu];
  48                 if (addr >= base &&
  49                     addr <= (base + THREAD_SIZE - sizeof(*regs)))
  50                         goto check_magic;
  51                 base = (unsigned long) softirq_stack[tp->cpu];
  52                 if (addr >= base &&
  53                     addr <= (base + THREAD_SIZE - sizeof(*regs)))
  54                         goto check_magic;
  55         }
  56         return false;
  57 
  58 check_magic:
  59         if ((regs->magic & ~0x1ff) == PT_REGS_MAGIC)
  60                 return true;
  61         return false;
  62 
  63 }
  64 
  65 static inline __attribute__((always_inline)) void *set_hardirq_stack(void)
  66 {
  67         void *orig_sp, *sp = hardirq_stack[smp_processor_id()];
  68 
  69         __asm__ __volatile__("mov %%sp, %0" : "=r" (orig_sp));
  70         if (orig_sp < sp ||
  71             orig_sp > (sp + THREAD_SIZE)) {
  72                 sp += THREAD_SIZE - 192 - STACK_BIAS;
  73                 __asm__ __volatile__("mov %0, %%sp" : : "r" (sp));
  74         }
  75 
  76         return orig_sp;
  77 }
  78 
  79 static inline __attribute__((always_inline)) void restore_hardirq_stack(void *orig_sp)
  80 {
  81         __asm__ __volatile__("mov %0, %%sp" : : "r" (orig_sp));
  82 }
  83 
  84 #endif /* _KSTACK_H */