/****************************************************************************** * os.h * * random collection of macros and definition */ #ifndef _XEN_OS_H_ #define _XEN_OS_H_ #include #ifdef PAE #define CONFIG_X86_PAE #endif #if !defined(__XEN_INTERFACE_VERSION__) /* * Can update to a more recent version when we implement * the hypercall page */ #define __XEN_INTERFACE_VERSION__ 0x00030204 #endif #include /* Force a proper event-channel callback from Xen. */ void force_evtchn_callback(void); #define likely(x) __builtin_expect((x),1) #define unlikely(x) __builtin_expect((x),0) #ifndef vtophys #include #include #include #endif extern int gdtset; #ifdef SMP #include /* XXX for pcpu.h */ #include /* XXX for PCPU_GET */ static inline int smp_processor_id(void) { if (likely(gdtset)) return PCPU_GET(cpuid); return 0; } #else #define smp_processor_id() 0 #endif #ifndef NULL #define NULL (void *)0 #endif #ifndef PANIC_IF #define PANIC_IF(exp) if (unlikely(exp)) {printk("panic - %s: %s:%d\n",#exp, __FILE__, __LINE__); panic("%s: %s:%d", #exp, __FILE__, __LINE__);} #endif extern shared_info_t *HYPERVISOR_shared_info; /* Somewhere in the middle of the GCC 2.96 development cycle, we implemented a mechanism by which the user can annotate likely branch directions and expect the blocks to be reordered appropriately. Define __builtin_expect to nothing for earlier compilers. */ /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */ static inline void rep_nop(void) { __asm__ __volatile__ ( "rep;nop" : : : "memory" ); } #define cpu_relax() rep_nop() #if __GNUC__ == 2 && __GNUC_MINOR__ < 96 #define __builtin_expect(x, expected_value) (x) #endif #define per_cpu(var, cpu) (pcpu_find((cpu))->pc_ ## var) /* crude memory allocator for memory allocation early in * boot */ void *bootmem_alloc(unsigned int size); void bootmem_free(void *ptr, unsigned int size); /* Everything below this point is not included by assembler (.S) files. */ #ifndef __ASSEMBLY__ #include void printk(const char *fmt, ...); /* some function prototypes */ void trap_init(void); #ifndef XENHVM /* * STI/CLI equivalents. These basically set and clear the virtual * event_enable flag in the shared_info structure. Note that when * the enable bit is set, there may be pending events to be handled. * We may therefore call into do_hypervisor_callback() directly. */ #define __cli() \ do { \ vcpu_info_t *_vcpu; \ _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ _vcpu->evtchn_upcall_mask = 1; \ barrier(); \ } while (0) #define __sti() \ do { \ vcpu_info_t *_vcpu; \ barrier(); \ _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ _vcpu->evtchn_upcall_mask = 0; \ barrier(); /* unmask then check (avoid races) */ \ if ( unlikely(_vcpu->evtchn_upcall_pending) ) \ force_evtchn_callback(); \ } while (0) #define __restore_flags(x) \ do { \ vcpu_info_t *_vcpu; \ barrier(); \ _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ if ((_vcpu->evtchn_upcall_mask = (x)) == 0) { \ barrier(); /* unmask then check (avoid races) */ \ if ( unlikely(_vcpu->evtchn_upcall_pending) ) \ force_evtchn_callback(); \ } \ } while (0) /* * Add critical_{enter, exit}? * */ #define __save_and_cli(x) \ do { \ vcpu_info_t *_vcpu; \ _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ (x) = _vcpu->evtchn_upcall_mask; \ _vcpu->evtchn_upcall_mask = 1; \ barrier(); \ } while (0) #define cli() __cli() #define sti() __sti() #define save_flags(x) __save_flags(x) #define restore_flags(x) __restore_flags(x) #define save_and_cli(x) __save_and_cli(x) #define local_irq_save(x) __save_and_cli(x) #define local_irq_restore(x) __restore_flags(x) #define local_irq_disable() __cli() #define local_irq_enable() __sti() #define mtx_lock_irqsave(lock, x) {local_irq_save((x)); mtx_lock_spin((lock));} #define mtx_unlock_irqrestore(lock, x) {mtx_unlock_spin((lock)); local_irq_restore((x)); } #define spin_lock_irqsave mtx_lock_irqsave #define spin_unlock_irqrestore mtx_unlock_irqrestore #endif #ifdef SMP #define smp_mb() mb() #define smp_rmb() rmb() #define smp_wmb() wmb() #define smp_read_barrier_depends() read_barrier_depends() #define set_mb(var, value) do { xchg(&var, value); } while (0) #else #define smp_mb() barrier() #define smp_rmb() barrier() #define smp_wmb() barrier() #define smp_read_barrier_depends() do { } while(0) #define set_mb(var, value) do { var = value; barrier(); } while (0) #endif /* This is a barrier for the compiler only, NOT the processor! */ #define barrier() __asm__ __volatile__("": : :"memory") #define LOCK_PREFIX "" #define LOCK "" #define ADDR (*(volatile long *) addr) /* * Make sure gcc doesn't try to be clever and move things around * on us. We need to use _exactly_ the address the user gave us, * not some alias that contains the same information. */ typedef struct { volatile int counter; } atomic_t; #define xen_xchg(ptr,v) \ ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr)))) struct __xchg_dummy { unsigned long a[100]; }; #define __xg(x) ((volatile struct __xchg_dummy *)(x)) static __inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { switch (size) { case 1: __asm__ __volatile__("xchgb %b0,%1" :"=q" (x) :"m" (*__xg(ptr)), "0" (x) :"memory"); break; case 2: __asm__ __volatile__("xchgw %w0,%1" :"=r" (x) :"m" (*__xg(ptr)), "0" (x) :"memory"); break; case 4: __asm__ __volatile__("xchgl %0,%1" :"=r" (x) :"m" (*__xg(ptr)), "0" (x) :"memory"); break; } return x; } /** * test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ static __inline int test_and_clear_bit(int nr, volatile void * addr) { int oldbit; __asm__ __volatile__( LOCK_PREFIX "btrl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit),"=m" (ADDR) :"Ir" (nr) : "memory"); return oldbit; } static __inline int constant_test_bit(int nr, const volatile void * addr) { return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0; } static __inline int variable_test_bit(int nr, volatile void * addr) { int oldbit; __asm__ __volatile__( "btl %2,%1\n\tsbbl %0,%0" :"=r" (oldbit) :"m" (ADDR),"Ir" (nr)); return oldbit; } #define test_bit(nr,addr) \ (__builtin_constant_p(nr) ? \ constant_test_bit((nr),(addr)) : \ variable_test_bit((nr),(addr))) /** * set_bit - Atomically set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * This function is atomic and may not be reordered. See __set_bit() * if you do not require the atomic guarantees. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ static __inline__ void set_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX "btsl %1,%0" :"=m" (ADDR) :"Ir" (nr)); } /** * clear_bit - Clears a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * clear_bit() is atomic and may not be reordered. However, it does * not contain a memory barrier, so if it is used for locking purposes, * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() * in order to ensure changes are visible on other processors. */ static __inline__ void clear_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX "btrl %1,%0" :"=m" (ADDR) :"Ir" (nr)); } /** * atomic_inc - increment atomic variable * @v: pointer of type atomic_t * * Atomically increments @v by 1. Note that the guaranteed * useful range of an atomic_t is only 24 bits. */ static __inline__ void atomic_inc(atomic_t *v) { __asm__ __volatile__( LOCK "incl %0" :"=m" (v->counter) :"m" (v->counter)); } #define rdtscll(val) \ __asm__ __volatile__("rdtsc" : "=A" (val)) /* * Kernel pointers have redundant information, so we can use a * scheme where we can return either an error code or a dentry * pointer with the same return value. * * This should be a per-architecture thing, to allow different * error and pointer decisions. */ #define IS_ERR_VALUE(x) unlikely((x) > (unsigned long)-1000L) static inline void *ERR_PTR(long error) { return (void *) error; } static inline long PTR_ERR(const void *ptr) { return (long) ptr; } static inline long IS_ERR(const void *ptr) { return IS_ERR_VALUE((unsigned long)ptr); } #endif /* !__ASSEMBLY__ */ #endif /* _OS_H_ */