LXR linux/arch/arm64/include/asm/daifflags.h

   1/*
   2 * Copyright (C) 2017 ARM Ltd.
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 as
   6 * published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 * GNU General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public License
  14 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15 */
  16#ifndef __ASM_DAIFFLAGS_H
  17#define __ASM_DAIFFLAGS_H
  18
  19#include <linux/irqflags.h>
  20
  21#define DAIF_PROCCTX            0
  22#define DAIF_PROCCTX_NOIRQ      PSR_I_BIT
  23
  24/* mask/save/unmask/restore all exceptions, including interrupts. */
  25static inline void local_daif_mask(void)
  26{
  27        asm volatile(
  28                "msr    daifset, #0xf           // local_daif_mask\n"
  29                :
  30                :
  31                : "memory");
  32        trace_hardirqs_off();
  33}
  34
  35static inline unsigned long local_daif_save(void)
  36{
  37        unsigned long flags;
  38
  39        asm volatile(
  40                "mrs    %0, daif                // local_daif_save\n"
  41                : "=r" (flags)
  42                :
  43                : "memory");
  44        local_daif_mask();
  45
  46        return flags;
  47}
  48
  49static inline void local_daif_unmask(void)
  50{
  51        trace_hardirqs_on();
  52        asm volatile(
  53                "msr    daifclr, #0xf           // local_daif_unmask"
  54                :
  55                :
  56                : "memory");
  57}
  58
  59static inline void local_daif_restore(unsigned long flags)
  60{
  61        if (!arch_irqs_disabled_flags(flags))
  62                trace_hardirqs_on();
  63        asm volatile(
  64                "msr    daif, %0                // local_daif_restore"
  65                :
  66                : "r" (flags)
  67                : "memory");
  68        if (arch_irqs_disabled_flags(flags))
  69                trace_hardirqs_off();
  70}
  71
  72#endif
  73