MUTEX_ALLOC(D3)

NAME
     MUTEX_ALLOC, MUTEX_INIT - mutual exclusion lock initialization

SYNOPSIS
     #include <sys/types.h>
     #include <sys/kmem.h>
     #include <sys/ksynch.h>
     #include <sys/ddi.h>
     mutex_t *MUTEX_ALLOC(int type, int flag, char *name);

     void MUTEX_INIT(mutex_t *mp, int type, char *name);

   Arguments
     type      Type of mutual exclusion lock -- must be MUTEX_DEFAULT.

     flag      Specifies whether the caller is willing to sleep waiting for
               memory.

     name      Name applied to the mutex -- only used when the metering locks
               package is installed.  Name may be a null pointer.

DESCRIPTION
     MUTEX_ALLOC dynamically allocates and initializes an instance of a
     sleeping mutual exclusion lock.  MUTEX_INIT initializes an already-
     allocated instance of a sleeping mutual exclusion lock.  The mutex is
     initialized to the unlocked state.

     If flag is set to KM_SLEEP, the caller will sleep if necessary until
     sufficient memory is available.  If flag is set to KM_NOSLEEP, the caller
     will not sleep, but MUTEX_ALLOC will return NULL if sufficient memory is
     not immediately available.

   Return Values
     Upon successful completion, MUTEX_ALLOC returns a pointer to the newly
     allocated lock.  If KM_NOSLEEP is specified and sufficient memory is not
     immediately available, MUTEX_ALLOC returns a NULL pointer.

USAGE
   Level
     Initialization or Base.

   Synchronization Constraints
     May sleep if flag is set to KM_SLEEP.

     Driver-defined basic locks be held across calls to this function if flag
     is KM_NOSLEEP but may not be held if flag is KM_SLEEP.

     Driver-defined sleep locks and read/write locks may be held across calls
     to this function regardless of the value of flag.
REFERENCES
     MUTEX_DEALLOC(D3), MUTEX_DESTROY(D3), MUTEX_LOCK(D3), MUTEX_TRYLOCK(D3),
     MUTEX_UNLOCK(D3), MUTEX_OWNED(D3), MUTEX_MINE(D3),