LXR linux/arch/sparc/kernel/kstack.h

   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.  */
  11static 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?  */
  37static 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
  58check_magic:
  59        if ((regs->magic & ~0x1ff) == PT_REGS_MAGIC)
  60                return true;
  61        return false;
  62
  63}
  64
  65static 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
  79static 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 */
  85