arch/sparc/kernel/kstack.h

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