include/asm-x86/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__(
  16                 "# __raw_save_flags\n\t"
  17                 "pushf ; pop %0"
  18                 : "=g" (flags)
  19                 : /* no input */
  20                 : "memory"
  21         );
  22
  23         return flags;
  24 }
  25
  26 static inline void native_restore_fl(unsigned long flags)
  27 {
  28         __asm__ __volatile__(
  29                 "push %0 ; popf"
  30                 : /* no output */
  31                 :"g" (flags)
  32                 :"memory", "cc"
  33         );
  34 }
  35
  36 static inline void native_irq_disable(void)
  37 {
  38         asm volatile("cli": : :"memory");
  39 }
  40
  41 static inline void native_irq_enable(void)
  42 {
  43         asm volatile("sti": : :"memory");
  44 }
  45
  46 static inline void native_safe_halt(void)
  47 {
  48         asm volatile("sti; hlt": : :"memory");
  49 }
  50
  51 static inline void native_halt(void)
  52 {
  53         asm volatile("hlt": : :"memory");
  54 }
  55
  56 #endif
  57
  58 #ifdef CONFIG_PARAVIRT
  59 #include <asm/paravirt.h>
  60 #else
  61 #ifndef __ASSEMBLY__
  62
  63 static inline unsigned long __raw_local_save_flags(void)
  64 {
  65         return native_save_fl();
  66 }
  67
  68 static inline void raw_local_irq_restore(unsigned long flags)
  69 {
  70         native_restore_fl(flags);
  71 }
  72
  73 static inline void raw_local_irq_disable(void)
  74 {
  75         native_irq_disable();
  76 }
  77
  78 static inline void raw_local_irq_enable(void)
  79 {
  80         native_irq_enable();
  81 }
  82
  83 /*
  84  * Used in the idle loop; sti takes one instruction cycle
  85  * to complete:
  86  */
  87 static inline void raw_safe_halt(void)
  88 {
  89         native_safe_halt();
  90 }
  91
  92 /*
  93  * Used when interrupts are already enabled or to
  94  * shutdown the processor:
  95  */
  96 static inline void halt(void)
  97 {
  98         native_halt();
  99 }
 100
 101 /*
 102  * For spinlocks, etc:
 103  */
 104 static inline unsigned long __raw_local_irq_save(void)
 105 {
 106         unsigned long flags = __raw_local_save_flags();
 107
 108         raw_local_irq_disable();
 109
 110         return flags;
 111 }
 112 #else
 113
 114 #define ENABLE_INTERRUPTS(x)    sti
 115 #define DISABLE_INTERRUPTS(x)   cli
 116
 117 #ifdef CONFIG_X86_64
 118 #define INTERRUPT_RETURN        iretq
 119 #define ENABLE_INTERRUPTS_SYSCALL_RET                   \
 120                         movq    %gs:pda_oldrsp, %rsp;   \
 121                         swapgs;                         \
 122                         sysretq;
 123 #else
 124 #define INTERRUPT_RETURN                iret
 125 #define ENABLE_INTERRUPTS_SYSCALL_RET   sti; sysexit
 126 #define GET_CR0_INTO_EAX                movl %cr0, %eax
 127 #endif
 128
 129
 130 #endif /* __ASSEMBLY__ */
 131 #endif /* CONFIG_PARAVIRT */
 132
 133 #ifndef __ASSEMBLY__
 134 #define raw_local_save_flags(flags) \
 135                 do { (flags) = __raw_local_save_flags(); } while (0)
 136
 137 #define raw_local_irq_save(flags) \
 138                 do { (flags) = __raw_local_irq_save(); } while (0)
 139
 140 static inline int raw_irqs_disabled_flags(unsigned long flags)
 141 {
 142         return !(flags & X86_EFLAGS_IF);
 143 }
 144
 145 static inline int raw_irqs_disabled(void)
 146 {
 147         unsigned long flags = __raw_local_save_flags();
 148
 149         return raw_irqs_disabled_flags(flags);
 150 }
 151
 152 /*
 153  * makes the traced hardirq state match with the machine state
 154  *
 155  * should be a rarely used function, only in places where its
 156  * otherwise impossible to know the irq state, like in traps.
 157  */
 158 static inline void trace_hardirqs_fixup_flags(unsigned long flags)
 159 {
 160         if (raw_irqs_disabled_flags(flags))
 161                 trace_hardirqs_off();
 162         else
 163                 trace_hardirqs_on();
 164 }
 165
 166 static inline void trace_hardirqs_fixup(void)
 167 {
 168         unsigned long flags = __raw_local_save_flags();
 169
 170         trace_hardirqs_fixup_flags(flags);
 171 }
 172
 173 #else
 174
 175 #ifdef CONFIG_X86_64
 176 /*
 177  * Currently paravirt can't handle swapgs nicely when we
 178  * don't have a stack we can rely on (such as a user space
 179  * stack).  So we either find a way around these or just fault
 180  * and emulate if a guest tries to call swapgs directly.
 181  *
 182  * Either way, this is a good way to document that we don't
 183  * have a reliable stack. x86_64 only.
 184  */
 185 #define SWAPGS_UNSAFE_STACK     swapgs
 186 #define ARCH_TRACE_IRQS_ON              call trace_hardirqs_on_thunk
 187 #define ARCH_TRACE_IRQS_OFF             call trace_hardirqs_off_thunk
 188 #define ARCH_LOCKDEP_SYS_EXIT           call lockdep_sys_exit_thunk
 189 #define ARCH_LOCKDEP_SYS_EXIT_IRQ       \
 190         TRACE_IRQS_ON; \
 191         sti; \
 192         SAVE_REST; \
 193         LOCKDEP_SYS_EXIT; \
 194         RESTORE_REST; \
 195         cli; \
 196         TRACE_IRQS_OFF;
 197
 198 #else
 199 #define ARCH_TRACE_IRQS_ON                      \
 200         pushl %eax;                             \
 201         pushl %ecx;                             \
 202         pushl %edx;                             \
 203         call trace_hardirqs_on;                 \
 204         popl %edx;                              \
 205         popl %ecx;                              \
 206         popl %eax;
 207
 208 #define ARCH_TRACE_IRQS_OFF                     \
 209         pushl %eax;                             \
 210         pushl %ecx;                             \
 211         pushl %edx;                             \
 212         call trace_hardirqs_off;                \
 213         popl %edx;                              \
 214         popl %ecx;                              \
 215         popl %eax;
 216
 217 #define ARCH_LOCKDEP_SYS_EXIT                   \
 218         pushl %eax;                             \
 219         pushl %ecx;                             \
 220         pushl %edx;                             \
 221         call lockdep_sys_exit;                  \
 222         popl %edx;                              \
 223         popl %ecx;                              \
 224         popl %eax;
 225
 226 #define ARCH_LOCKDEP_SYS_EXIT_IRQ
 227 #endif
 228
 229 #ifdef CONFIG_TRACE_IRQFLAGS
 230 #  define TRACE_IRQS_ON         ARCH_TRACE_IRQS_ON
 231 #  define TRACE_IRQS_OFF        ARCH_TRACE_IRQS_OFF
 232 #else
 233 #  define TRACE_IRQS_ON
 234 #  define TRACE_IRQS_OFF
 235 #endif
 236 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 237 #  define LOCKDEP_SYS_EXIT      ARCH_LOCKDEP_SYS_EXIT
 238 #  define LOCKDEP_SYS_EXIT_IRQ  ARCH_LOCKDEP_SYS_EXIT_IRQ
 239 # else
 240 #  define LOCKDEP_SYS_EXIT
 241 #  define LOCKDEP_SYS_EXIT_IRQ
 242 # endif
 243
 244 #endif /* __ASSEMBLY__ */
 245 #endif