kstack.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _KSTACK_H
#define _KSTACK_H
#include <linux/thread_info.h>
#include <linux/sched.h>
#include <asm/ptrace.h>
#include <asm/irq.h>
/* SP must be STACK_BIAS adjusted already. */
static inline bool kstack_valid(struct thread_info *tp, unsigned long sp)
{
unsigned long base = (unsigned long) tp;
/* Stack pointer must be 16-byte aligned. */
if (sp & (16UL - 1))
return false;
if (sp >= (base + sizeof(struct thread_info)) &&
sp <= (base + THREAD_SIZE - sizeof(struct sparc_stackf)))
return true;
if (hardirq_stack[tp->cpu]) {
base = (unsigned long) hardirq_stack[tp->cpu];
if (sp >= base &&
sp <= (base + THREAD_SIZE - sizeof(struct sparc_stackf)))
return true;
base = (unsigned long) softirq_stack[tp->cpu];
if (sp >= base &&
sp <= (base + THREAD_SIZE - sizeof(struct sparc_stackf)))
return true;
}
return false;
}
/* Does "regs" point to a valid pt_regs trap frame? */
static inline bool kstack_is_trap_frame(struct thread_info *tp, struct pt_regs *regs)
{
unsigned long base = (unsigned long) tp;
unsigned long addr = (unsigned long) regs;
if (addr >= base &&
addr <= (base + THREAD_SIZE - sizeof(*regs)))
goto check_magic;
if (hardirq_stack[tp->cpu]) {
base = (unsigned long) hardirq_stack[tp->cpu];
if (addr >= base &&
addr <= (base + THREAD_SIZE - sizeof(*regs)))
goto check_magic;
base = (unsigned long) softirq_stack[tp->cpu];
if (addr >= base &&
addr <= (base + THREAD_SIZE - sizeof(*regs)))
goto check_magic;
}
return false;
check_magic:
if ((regs->magic & ~0x1ff) == PT_REGS_MAGIC)
return true;
return false;
}
static inline __attribute__((always_inline)) void *set_hardirq_stack(void)
{
void *orig_sp, *sp = hardirq_stack[smp_processor_id()];
__asm__ __volatile__("mov %%sp, %0" : "=r" (orig_sp));
if (orig_sp < sp ||
orig_sp > (sp + THREAD_SIZE)) {
sp += THREAD_SIZE - 192 - STACK_BIAS;
__asm__ __volatile__("mov %0, %%sp" : : "r" (sp));
}
return orig_sp;
}
static inline __attribute__((always_inline)) void restore_hardirq_stack(void *orig_sp)
{
__asm__ __volatile__("mov %0, %%sp" : : "r" (orig_sp));
}
#endif /* _KSTACK_H */