zfs/include/sys/callb.h

#ifndef _SPL_CALLB_H
#define _SPL_CALLB_H

#ifdef  __cplusplus
extern "C" {
#endif

#include <linux/module.h>
#include <sys/mutex.h>

#define DEBUG_CALLB

#ifndef DEBUG_CALLB
#define CALLB_CPR_ASSERT(cp)		ASSERT(MUTEX_HELD((cp)->cc_lockp));
#else
#define CALLB_CPR_ASSERT(cp)
#endif


typedef struct callb_cpr {
        kmutex_t        *cc_lockp;
} callb_cpr_t;

#define CALLB_CPR_INIT(cp, lockp, func, name)   {               \
        (cp)->cc_lockp = lockp;                                 \
}

#define CALLB_CPR_SAFE_BEGIN(cp) {                              \
	CALLB_CPR_ASSERT(cp);					\
}

#define CALLB_CPR_SAFE_END(cp, lockp) {                         \
	CALLB_CPR_ASSERT(cp);					\
}

#define CALLB_CPR_EXIT(cp) {                                    \
        ASSERT(MUTEX_HELD((cp)->cc_lockp));                     \
        mutex_exit((cp)->cc_lockp);                             \
}

#ifdef  __cplusplus
}
#endif

#endif  /* _SPL_CALLB_H */