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 #ifdef CONFIG_X86_VSMP
  74
  75 /*
  76  * Interrupt control for the VSMP architecture:
  77  */
  78
  79 static inline void raw_local_irq_disable(void)
  80 {
  81         unsigned long flags = __raw_local_save_flags();
  82         raw_local_irq_restore((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
  83 }
  84
  85 static inline void raw_local_irq_enable(void)
  86 {
  87         unsigned long flags = __raw_local_save_flags();
  88         raw_local_irq_restore((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
  89 }
  90
  91 #else
  92
  93 static inline void raw_local_irq_disable(void)
  94 {
  95         native_irq_disable();
  96 }
  97
  98 static inline void raw_local_irq_enable(void)
  99 {
 100         native_irq_enable();
 101 }
 102
 103 #endif
 104
 105 /*
 106  * Used in the idle loop; sti takes one instruction cycle
 107  * to complete:
 108  */
 109 static inline void raw_safe_halt(void)
 110 {
 111         native_safe_halt();
 112 }
 113
 114 /*
 115  * Used when interrupts are already enabled or to
 116  * shutdown the processor:
 117  */
 118 static inline void halt(void)
 119 {
 120         native_halt();
 121 }
 122
 123 /*
 124  * For spinlocks, etc:
 125  */
 126 static inline unsigned long __raw_local_irq_save(void)
 127 {
 128         unsigned long flags = __raw_local_save_flags();
 129
 130         raw_local_irq_disable();
 131
 132         return flags;
 133 }
 134 #else
 135
 136 #define ENABLE_INTERRUPTS(x)    sti
 137 #define DISABLE_INTERRUPTS(x)   cli
 138
 139 #ifdef CONFIG_X86_64
 140 #define INTERRUPT_RETURN        iretq
 141 #define ENABLE_INTERRUPTS_SYSCALL_RET                   \
 142                         movq    %gs:pda_oldrsp, %rsp;   \
 143                         swapgs;                         \
 144                         sysretq;
 145 #else
 146 #define INTERRUPT_RETURN                iret
 147 #define ENABLE_INTERRUPTS_SYSCALL_RET   sti; sysexit
 148 #define GET_CR0_INTO_EAX                movl %cr0, %eax
 149 #endif
 150
 151
 152 #endif /* __ASSEMBLY__ */
 153 #endif /* CONFIG_PARAVIRT */
 154
 155 #ifndef __ASSEMBLY__
 156 #define raw_local_save_flags(flags) \
 157                 do { (flags) = __raw_local_save_flags(); } while (0)
 158
 159 #define raw_local_irq_save(flags) \
 160                 do { (flags) = __raw_local_irq_save(); } while (0)
 161
 162 #ifdef CONFIG_X86_VSMP
 163 static inline int raw_irqs_disabled_flags(unsigned long flags)
 164 {
 165         return !(flags & X86_EFLAGS_IF) || (flags & X86_EFLAGS_AC);
 166 }
 167 #else
 168 static inline int raw_irqs_disabled_flags(unsigned long flags)
 169 {
 170         return !(flags & X86_EFLAGS_IF);
 171 }
 172 #endif
 173
 174 static inline int raw_irqs_disabled(void)
 175 {
 176         unsigned long flags = __raw_local_save_flags();
 177
 178         return raw_irqs_disabled_flags(flags);
 179 }
 180
 181 /*
 182  * makes the traced hardirq state match with the machine state
 183  *
 184  * should be a rarely used function, only in places where its
 185  * otherwise impossible to know the irq state, like in traps.
 186  */
 187 static inline void trace_hardirqs_fixup_flags(unsigned long flags)
 188 {
 189         if (raw_irqs_disabled_flags(flags))
 190                 trace_hardirqs_off();
 191         else
 192                 trace_hardirqs_on();
 193 }
 194
 195 static inline void trace_hardirqs_fixup(void)
 196 {
 197         unsigned long flags = __raw_local_save_flags();
 198
 199         trace_hardirqs_fixup_flags(flags);
 200 }
 201
 202 #else
 203
 204 #ifdef CONFIG_X86_64
 205 /*
 206  * Currently paravirt can't handle swapgs nicely when we
 207  * don't have a stack we can rely on (such as a user space
 208  * stack).  So we either find a way around these or just fault
 209  * and emulate if a guest tries to call swapgs directly.
 210  *
 211  * Either way, this is a good way to document that we don't
 212  * have a reliable stack. x86_64 only.
 213  */
 214 #define SWAPGS_UNSAFE_STACK     swapgs
 215 #define ARCH_TRACE_IRQS_ON              call trace_hardirqs_on_thunk
 216 #define ARCH_TRACE_IRQS_OFF             call trace_hardirqs_off_thunk
 217 #define ARCH_LOCKDEP_SYS_EXIT           call lockdep_sys_exit_thunk
 218 #define ARCH_LOCKDEP_SYS_EXIT_IRQ       \
 219         TRACE_IRQS_ON; \
 220         sti; \
 221         SAVE_REST; \
 222         LOCKDEP_SYS_EXIT; \
 223         RESTORE_REST; \
 224         cli; \
 225         TRACE_IRQS_OFF;
 226
 227 #else
 228 #define ARCH_TRACE_IRQS_ON                      \
 229         pushl %eax;                             \
 230         pushl %ecx;                             \
 231         pushl %edx;                             \
 232         call trace_hardirqs_on;                 \
 233         popl %edx;                              \
 234         popl %ecx;                              \
 235         popl %eax;
 236
 237 #define ARCH_TRACE_IRQS_OFF                     \
 238         pushl %eax;                             \
 239         pushl %ecx;                             \
 240         pushl %edx;                             \
 241         call trace_hardirqs_off;                \
 242         popl %edx;                              \
 243         popl %ecx;                              \
 244         popl %eax;
 245
 246 #define ARCH_LOCKDEP_SYS_EXIT                   \
 247         pushl %eax;                             \
 248         pushl %ecx;                             \
 249         pushl %edx;                             \
 250         call lockdep_sys_exit;                  \
 251         popl %edx;                              \
 252         popl %ecx;                              \
 253         popl %eax;
 254
 255 #define ARCH_LOCKDEP_SYS_EXIT_IRQ
 256 #endif
 257
 258 #ifdef CONFIG_TRACE_IRQFLAGS
 259 #  define TRACE_IRQS_ON         ARCH_TRACE_IRQS_ON
 260 #  define TRACE_IRQS_OFF        ARCH_TRACE_IRQS_OFF
 261 #else
 262 #  define TRACE_IRQS_ON
 263 #  define TRACE_IRQS_OFF
 264 #endif
 265 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 266 #  define LOCKDEP_SYS_EXIT      ARCH_LOCKDEP_SYS_EXIT
 267 #  define LOCKDEP_SYS_EXIT_IRQ  ARCH_LOCKDEP_SYS_EXIT_IRQ
 268 # else
 269 #  define LOCKDEP_SYS_EXIT
 270 #  define LOCKDEP_SYS_EXIT_IRQ
 271 # endif
 272
 273 #endif /* __ASSEMBLY__ */
 274 #endif