arch/x86/include/asm/irqflags.h

   1 #ifndef _X86_IRQFLAGS_H_
   2 #define _X86_IRQFLAGS_H_
   3
   4 #include <asm/processor-flags.h>
   5
   6 #ifndef __ASSEMBLY__
   7 /*
   8  * Interrupt control:
   9  */
  10
  11 static inline unsigned long native_save_fl(void)
  12 {
  13         unsigned long flags;
  14
  15         asm volatile("# __raw_save_flags\n\t"
  16                      "pushf ; pop %0"
  17                      : "=g" (flags)
  18                      : /* no input */
  19                      : "memory");
  20
  21         return flags;
  22 }
  23
  24 static inline void native_restore_fl(unsigned long flags)
  25 {
  26         asm volatile("push %0 ; popf"
  27                      : /* no output */
  28                      :"g" (flags)
  29                      :"memory", "cc");
  30 }
  31
  32 static inline void native_irq_disable(void)
  33 {
  34         asm volatile("cli": : :"memory");
  35 }
  36
  37 static inline void native_irq_enable(void)
  38 {
  39         asm volatile("sti": : :"memory");
  40 }
  41
  42 static inline void native_safe_halt(void)
  43 {
  44         asm volatile("sti; hlt": : :"memory");
  45 }
  46
  47 static inline void native_halt(void)
  48 {
  49         asm volatile("hlt": : :"memory");
  50 }
  51
  52 #endif
  53
  54 #ifdef CONFIG_PARAVIRT
  55 #include <asm/paravirt.h>
  56 #else
  57 #ifndef __ASSEMBLY__
  58
  59 static inline unsigned long __raw_local_save_flags(void)
  60 {
  61         return native_save_fl();
  62 }
  63
  64 static inline void raw_local_irq_restore(unsigned long flags)
  65 {
  66         native_restore_fl(flags);
  67 }
  68
  69 static inline void raw_local_irq_disable(void)
  70 {
  71         native_irq_disable();
  72 }
  73
  74 static inline void raw_local_irq_enable(void)
  75 {
  76         native_irq_enable();
  77 }
  78
  79 /*
  80  * Used in the idle loop; sti takes one instruction cycle
  81  * to complete:
  82  */
  83 static inline void raw_safe_halt(void)
  84 {
  85         native_safe_halt();
  86 }
  87
  88 /*
  89  * Used when interrupts are already enabled or to
  90  * shutdown the processor:
  91  */
  92 static inline void halt(void)
  93 {
  94         native_halt();
  95 }
  96
  97 /*
  98  * For spinlocks, etc:
  99  */
 100 static inline unsigned long __raw_local_irq_save(void)
 101 {
 102         unsigned long flags = __raw_local_save_flags();
 103
 104         raw_local_irq_disable();
 105
 106         return flags;
 107 }
 108 #else
 109
 110 #define ENABLE_INTERRUPTS(x)    sti
 111 #define DISABLE_INTERRUPTS(x)   cli
 112
 113 #ifdef CONFIG_X86_64
 114 #define SWAPGS  swapgs
 115 /*
 116  * Currently paravirt can't handle swapgs nicely when we
 117  * don't have a stack we can rely on (such as a user space
 118  * stack).  So we either find a way around these or just fault
 119  * and emulate if a guest tries to call swapgs directly.
 120  *
 121  * Either way, this is a good way to document that we don't
 122  * have a reliable stack. x86_64 only.
 123  */
 124 #define SWAPGS_UNSAFE_STACK     swapgs
 125
 126 #define PARAVIRT_ADJUST_EXCEPTION_FRAME /*  */
 127
 128 #define INTERRUPT_RETURN        iretq
 129 #define USERGS_SYSRET64                         \
 130         swapgs;                                 \
 131         sysretq;
 132 #define USERGS_SYSRET32                         \
 133         swapgs;                                 \
 134         sysretl
 135 #define ENABLE_INTERRUPTS_SYSEXIT32             \
 136         swapgs;                                 \
 137         sti;                                    \
 138         sysexit
 139
 140 #else
 141 #define INTERRUPT_RETURN                iret
 142 #define ENABLE_INTERRUPTS_SYSEXIT       sti; sysexit
 143 #define GET_CR0_INTO_EAX                movl %cr0, %eax
 144 #endif
 145
 146
 147 #endif /* __ASSEMBLY__ */
 148 #endif /* CONFIG_PARAVIRT */
 149
 150 #ifndef __ASSEMBLY__
 151 #define raw_local_save_flags(flags)                             \
 152         do { (flags) = __raw_local_save_flags(); } while (0)
 153
 154 #define raw_local_irq_save(flags)                               \
 155         do { (flags) = __raw_local_irq_save(); } while (0)
 156
 157 static inline int raw_irqs_disabled_flags(unsigned long flags)
 158 {
 159         return !(flags & X86_EFLAGS_IF);
 160 }
 161
 162 static inline int raw_irqs_disabled(void)
 163 {
 164         unsigned long flags = __raw_local_save_flags();
 165
 166         return raw_irqs_disabled_flags(flags);
 167 }
 168
 169 #else
 170
 171 #ifdef CONFIG_X86_64
 172 #define ARCH_LOCKDEP_SYS_EXIT           call lockdep_sys_exit_thunk
 173 #define ARCH_LOCKDEP_SYS_EXIT_IRQ       \
 174         TRACE_IRQS_ON; \
 175         sti; \
 176         SAVE_REST; \
 177         LOCKDEP_SYS_EXIT; \
 178         RESTORE_REST; \
 179         cli; \
 180         TRACE_IRQS_OFF;
 181
 182 #else
 183 #define ARCH_LOCKDEP_SYS_EXIT                   \
 184         pushl %eax;                             \
 185         pushl %ecx;                             \
 186         pushl %edx;                             \
 187         call lockdep_sys_exit;                  \
 188         popl %edx;                              \
 189         popl %ecx;                              \
 190         popl %eax;
 191
 192 #define ARCH_LOCKDEP_SYS_EXIT_IRQ
 193 #endif
 194
 195 #ifdef CONFIG_TRACE_IRQFLAGS
 196 #  define TRACE_IRQS_ON         call trace_hardirqs_on_thunk;
 197 #  define TRACE_IRQS_OFF        call trace_hardirqs_off_thunk;
 198 #else
 199 #  define TRACE_IRQS_ON
 200 #  define TRACE_IRQS_OFF
 201 #endif
 202 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 203 #  define LOCKDEP_SYS_EXIT      ARCH_LOCKDEP_SYS_EXIT
 204 #  define LOCKDEP_SYS_EXIT_IRQ  ARCH_LOCKDEP_SYS_EXIT_IRQ
 205 # else
 206 #  define LOCKDEP_SYS_EXIT
 207 #  define LOCKDEP_SYS_EXIT_IRQ
 208 # endif
 209
 210 #endif /* __ASSEMBLY__ */
 211 #endif