#ifndef __LINUX_SPINLOCK_H
  #define __LINUX_SPINLOCK_H
  
  /*

   * include/linux/spinlock.h - generic spinlock/rwlock declarations
   *
   * here's the role of the various spinlock/rwlock related include files:
   *
   * on SMP builds:
   *
   *  asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
   *                        initializers
   *
   *  linux/spinlock_types.h:
   *                        defines the generic type and initializers
   *
   *  asm/spinlock.h:       contains the __raw_spin_*()/etc. lowlevel
   *                        implementations, mostly inline assembly code
   *
   *   (also included on UP-debug builds:)
   *
   *  linux/spinlock_api_smp.h:
   *                        contains the prototypes for the _spin_*() APIs.
   *
   *  linux/spinlock.h:     builds the final spin_*() APIs.
   *
   * on UP builds:
   *
   *  linux/spinlock_type_up.h:
   *                        contains the generic, simplified UP spinlock type.
   *                        (which is an empty structure on non-debug builds)
   *
   *  linux/spinlock_types.h:
   *                        defines the generic type and initializers
   *
   *  linux/spinlock_up.h:
   *                        contains the __raw_spin_*()/etc. version of UP
   *                        builds. (which are NOPs on non-debug, non-preempt
   *                        builds)
   *
   *   (included on UP-non-debug builds:)
   *
   *  linux/spinlock_api_up.h:
   *                        builds the _spin_*() APIs.
   *
   *  linux/spinlock.h:     builds the final spin_*() APIs.

   */

  #include <linux/preempt.h>
  #include <linux/linkage.h>
  #include <linux/compiler.h>
  #include <linux/thread_info.h>
  #include <linux/kernel.h>
  #include <linux/stringify.h>

  #include <linux/bottom_half.h>

  #include <asm/system.h>
  
  /*
   * Must define these before including other files, inline functions need them
   */

  #define LOCK_SECTION_NAME ".text.lock."KBUILD_BASENAME

  
  #define LOCK_SECTION_START(extra)               \
          ".subsection 1
  \t"                     \
          extra                                   \
          ".ifndef " LOCK_SECTION_NAME "
  \t"     \
          LOCK_SECTION_NAME ":
  \t"               \
          ".endif
  "
  
  #define LOCK_SECTION_END                        \
          ".previous
  \t"
  
  #define __lockfunc fastcall __attribute__((section(".spinlock.text")))
  
  /*

   * Pull the raw_spinlock_t and raw_rwlock_t definitions:

   */

  #include <linux/spinlock_types.h>

  extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);

  /*

   * Pull the __raw*() functions/declarations (UP-nondebug doesnt need them):

   */

  #ifdef CONFIG_SMP

  # include <asm/spinlock.h>

  #else

  # include <linux/spinlock_up.h>

  #endif

  #ifdef CONFIG_DEBUG_SPINLOCK
    extern void __spin_lock_init(spinlock_t *lock, const char *name,
  			       struct lock_class_key *key);
  # define spin_lock_init(lock)					\
  do {								\
  	static struct lock_class_key __key;			\
  								\
  	__spin_lock_init((lock), #lock, &__key);		\
  } while (0)
  
  #else
  # define spin_lock_init(lock)					\
  	do { *(lock) = SPIN_LOCK_UNLOCKED; } while (0)
  #endif
  
  #ifdef CONFIG_DEBUG_SPINLOCK
    extern void __rwlock_init(rwlock_t *lock, const char *name,
  			    struct lock_class_key *key);
  # define rwlock_init(lock)					\
  do {								\
  	static struct lock_class_key __key;			\
  								\
  	__rwlock_init((lock), #lock, &__key);			\
  } while (0)
  #else
  # define rwlock_init(lock)					\
  	do { *(lock) = RW_LOCK_UNLOCKED; } while (0)
  #endif

  
  #define spin_is_locked(lock)	__raw_spin_is_locked(&(lock)->raw_lock)
  
  /**
   * spin_unlock_wait - wait until the spinlock gets unlocked
   * @lock: the spinlock in question.
   */
  #define spin_unlock_wait(lock)	__raw_spin_unlock_wait(&(lock)->raw_lock)

  /*

   * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:

   */

  #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
  # include <linux/spinlock_api_smp.h>

  #else

  # include <linux/spinlock_api_up.h>

  #endif

  #ifdef CONFIG_DEBUG_SPINLOCK
   extern void _raw_spin_lock(spinlock_t *lock);
  #define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
   extern int _raw_spin_trylock(spinlock_t *lock);
   extern void _raw_spin_unlock(spinlock_t *lock);

   extern void _raw_read_lock(rwlock_t *lock);
   extern int _raw_read_trylock(rwlock_t *lock);
   extern void _raw_read_unlock(rwlock_t *lock);
   extern void _raw_write_lock(rwlock_t *lock);
   extern int _raw_write_trylock(rwlock_t *lock);
   extern void _raw_write_unlock(rwlock_t *lock);
  #else

  # define _raw_spin_lock(lock)		__raw_spin_lock(&(lock)->raw_lock)
  # define _raw_spin_lock_flags(lock, flags) \
  		__raw_spin_lock_flags(&(lock)->raw_lock, *(flags))

  # define _raw_spin_trylock(lock)	__raw_spin_trylock(&(lock)->raw_lock)
  # define _raw_spin_unlock(lock)		__raw_spin_unlock(&(lock)->raw_lock)

  # define _raw_read_lock(rwlock)		__raw_read_lock(&(rwlock)->raw_lock)

  # define _raw_read_trylock(rwlock)	__raw_read_trylock(&(rwlock)->raw_lock)

  # define _raw_read_unlock(rwlock)	__raw_read_unlock(&(rwlock)->raw_lock)
  # define _raw_write_lock(rwlock)	__raw_write_lock(&(rwlock)->raw_lock)

  # define _raw_write_trylock(rwlock)	__raw_write_trylock(&(rwlock)->raw_lock)

  # define _raw_write_unlock(rwlock)	__raw_write_unlock(&(rwlock)->raw_lock)

  #endif

  #define read_can_lock(rwlock)		__raw_read_can_lock(&(rwlock)->raw_lock)
  #define write_can_lock(rwlock)		__raw_write_can_lock(&(rwlock)->raw_lock)

  
  /*
   * Define the various spin_lock and rw_lock methods.  Note we define these
   * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various
   * methods are defined as nops in the case they are not required.
   */

  #define spin_trylock(lock)		__cond_lock(lock, _spin_trylock(lock))
  #define read_trylock(lock)		__cond_lock(lock, _read_trylock(lock))
  #define write_trylock(lock)		__cond_lock(lock, _write_trylock(lock))

  #define spin_lock(lock)			_spin_lock(lock)

  
  #ifdef CONFIG_DEBUG_LOCK_ALLOC
  # define spin_lock_nested(lock, subclass) _spin_lock_nested(lock, subclass)
  #else
  # define spin_lock_nested(lock, subclass) _spin_lock(lock)
  #endif

  #define write_lock(lock)		_write_lock(lock)
  #define read_lock(lock)			_read_lock(lock)

  #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)

  
  #define spin_lock_irqsave(lock, flags)	flags = _spin_lock_irqsave(lock)
  #define read_lock_irqsave(lock, flags)	flags = _read_lock_irqsave(lock)
  #define write_lock_irqsave(lock, flags)	flags = _write_lock_irqsave(lock)

  
  #ifdef CONFIG_DEBUG_LOCK_ALLOC

  #define spin_lock_irqsave_nested(lock, flags, subclass) \
  	flags = _spin_lock_irqsave_nested(lock, subclass)

  #else

  #define spin_lock_irqsave_nested(lock, flags, subclass) \
  	flags = _spin_lock_irqsave(lock)

  #endif

  #else

  
  #define spin_lock_irqsave(lock, flags)	_spin_lock_irqsave(lock, flags)
  #define read_lock_irqsave(lock, flags)	_read_lock_irqsave(lock, flags)
  #define write_lock_irqsave(lock, flags)	_write_lock_irqsave(lock, flags)

  #define spin_lock_irqsave_nested(lock, flags, subclass)	\
  	spin_lock_irqsave(lock, flags)

  #endif
  
  #define spin_lock_irq(lock)		_spin_lock_irq(lock)
  #define spin_lock_bh(lock)		_spin_lock_bh(lock)
  
  #define read_lock_irq(lock)		_read_lock_irq(lock)
  #define read_lock_bh(lock)		_read_lock_bh(lock)
  
  #define write_lock_irq(lock)		_write_lock_irq(lock)
  #define write_lock_bh(lock)		_write_lock_bh(lock)

  /*
   * We inline the unlock functions in the nondebug case:
   */

  #if defined(CONFIG_DEBUG_SPINLOCK) || defined(CONFIG_PREEMPT) || \
  	!defined(CONFIG_SMP)

  # define spin_unlock(lock)		_spin_unlock(lock)
  # define read_unlock(lock)		_read_unlock(lock)
  # define write_unlock(lock)		_write_unlock(lock)

  # define spin_unlock_irq(lock)		_spin_unlock_irq(lock)
  # define read_unlock_irq(lock)		_read_unlock_irq(lock)
  # define write_unlock_irq(lock)		_write_unlock_irq(lock)
  #else

  # define spin_unlock(lock) \
      do {__raw_spin_unlock(&(lock)->raw_lock); __release(lock); } while (0)
  # define read_unlock(lock) \
      do {__raw_read_unlock(&(lock)->raw_lock); __release(lock); } while (0)
  # define write_unlock(lock) \
      do {__raw_write_unlock(&(lock)->raw_lock); __release(lock); } while (0)
  # define spin_unlock_irq(lock)			\
  do {						\
  	__raw_spin_unlock(&(lock)->raw_lock);	\
  	__release(lock);			\
  	local_irq_enable();			\
  } while (0)
  # define read_unlock_irq(lock)			\
  do {						\
  	__raw_read_unlock(&(lock)->raw_lock);	\
  	__release(lock);			\
  	local_irq_enable();			\
  } while (0)
  # define write_unlock_irq(lock)			\
  do {						\
  	__raw_write_unlock(&(lock)->raw_lock);	\
  	__release(lock);			\
  	local_irq_enable();			\
  } while (0)

  #endif

  #define spin_unlock_irqrestore(lock, flags) \

  					_spin_unlock_irqrestore(lock, flags)

  #define spin_unlock_bh(lock)		_spin_unlock_bh(lock)

  #define read_unlock_irqrestore(lock, flags) \

  					_read_unlock_irqrestore(lock, flags)

  #define read_unlock_bh(lock)		_read_unlock_bh(lock)

  #define write_unlock_irqrestore(lock, flags) \

  					_write_unlock_irqrestore(lock, flags)

  #define write_unlock_bh(lock)		_write_unlock_bh(lock)

  #define spin_trylock_bh(lock)	__cond_lock(lock, _spin_trylock_bh(lock))

  
  #define spin_trylock_irq(lock) \
  ({ \
  	local_irq_disable(); \

  	spin_trylock(lock) ? \

  	1 : ({ local_irq_enable(); 0;  }); \

  })
  
  #define spin_trylock_irqsave(lock, flags) \
  ({ \
  	local_irq_save(flags); \

  	spin_trylock(lock) ? \

  	1 : ({ local_irq_restore(flags); 0; }); \

  })

  #define write_trylock_irqsave(lock, flags) \
  ({ \
  	local_irq_save(flags); \
  	write_trylock(lock) ? \
  	1 : ({ local_irq_restore(flags); 0; }); \
  })

  /*

   * Locks two spinlocks l1 and l2.
   * l1_first indicates if spinlock l1 should be taken first.
   */
  static inline void double_spin_lock(spinlock_t *l1, spinlock_t *l2,
  				    bool l1_first)
  	__acquires(l1)
  	__acquires(l2)
  {
  	if (l1_first) {
  		spin_lock(l1);
  		spin_lock(l2);
  	} else {
  		spin_lock(l2);
  		spin_lock(l1);
  	}
  }
  
  /*
   * Unlocks two spinlocks l1 and l2.
   * l1_taken_first indicates if spinlock l1 was taken first and therefore
   * should be released after spinlock l2.
   */
  static inline void double_spin_unlock(spinlock_t *l1, spinlock_t *l2,
  				      bool l1_taken_first)
  	__releases(l1)
  	__releases(l2)
  {
  	if (l1_taken_first) {
  		spin_unlock(l2);
  		spin_unlock(l1);
  	} else {
  		spin_unlock(l1);
  		spin_unlock(l2);
  	}
  }
  
  /*

   * Pull the atomic_t declaration:
   * (asm-mips/atomic.h needs above definitions)

   */

  #include <asm/atomic.h>
  /**
   * atomic_dec_and_lock - lock on reaching reference count zero
   * @atomic: the atomic counter
   * @lock: the spinlock in question

   */

  extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
  #define atomic_dec_and_lock(atomic, lock) \

  		__cond_lock(lock, _atomic_dec_and_lock(atomic, lock))

  
  /**
   * spin_can_lock - would spin_trylock() succeed?
   * @lock: the spinlock in question.
   */

  #define spin_can_lock(lock)	(!spin_is_locked(lock))

  
  #endif /* __LINUX_SPINLOCK_H */