uvm_map.h

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 *	Interrupt-safe maps must also be kept on a special list,
 *	to assist uvm_fault() in avoiding locking problems.
 */
struct vm_map_intrsafe {
	struct vm_map	vmi_map;
	LIST_ENTRY(vm_map_intrsafe) vmi_list;
};

LIST_HEAD(vmi_list, vm_map_intrsafe);
#ifdef _KERNEL
extern simple_lock_data_t vmi_list_slock;
extern struct vmi_list vmi_list;

static __inline int vmi_list_lock __P((void));
static __inline void vmi_list_unlock __P((int));

static __inline int
vmi_list_lock()
{
	int s;

#ifndef OSKIT	/* XXX */
	s = splhigh();
	simple_lock(&vmi_list_slock);
#else
	s = 0;
#endif
	return (s);
}

static __inline void
vmi_list_unlock(s)
	int s;
{
#ifndef OSKIT
	simple_unlock(&vmi_list_slock);
	splx(s);
#endif
}
#endif /* _KERNEL */

/*
 * handle inline options
 */

#ifdef UVM_MAP_INLINE
#define MAP_INLINE static __inline
#else 
#define MAP_INLINE /* nothing */
#endif /* UVM_MAP_INLINE */

/*
 * globals:
 */

#ifdef _KERNEL

#ifdef PMAP_GROWKERNEL
extern vaddr_t	uvm_maxkaddr;
#endif

/*
 * protos: the following prototypes define the interface to vm_map
 */

MAP_INLINE
void		uvm_map_deallocate __P((vm_map_t));

int		uvm_map_clean __P((vm_map_t, vaddr_t, vaddr_t, int));
void		uvm_map_clip_start __P((vm_map_t, vm_map_entry_t, vaddr_t));
void		uvm_map_clip_end __P((vm_map_t, vm_map_entry_t, vaddr_t));
MAP_INLINE
vm_map_t	uvm_map_create __P((pmap_t, vaddr_t, vaddr_t, int));
int		uvm_map_extract __P((vm_map_t, vaddr_t, vsize_t, 
			vm_map_t, vaddr_t *, int));
vm_map_entry_t	uvm_map_findspace __P((vm_map_t, vaddr_t, vsize_t, vaddr_t *,
			struct uvm_object *, voff_t, vsize_t, int));
int		uvm_map_inherit __P((vm_map_t, vaddr_t, vaddr_t, vm_inherit_t));
int		uvm_map_advice __P((vm_map_t, vaddr_t, vaddr_t, int));
void		uvm_map_init __P((void));
boolean_t	uvm_map_lookup_entry __P((vm_map_t, vaddr_t, vm_map_entry_t *));
MAP_INLINE
void		uvm_map_reference __P((vm_map_t));
int		uvm_map_replace __P((vm_map_t, vaddr_t, vaddr_t,
			vm_map_entry_t, int));
int		uvm_map_reserve __P((vm_map_t, vsize_t, vaddr_t, vsize_t,
			vaddr_t *));
void		uvm_map_setup __P((vm_map_t, vaddr_t, vaddr_t, int));
int		uvm_map_submap __P((vm_map_t, vaddr_t, vaddr_t, vm_map_t));
MAP_INLINE
int		uvm_unmap __P((vm_map_t, vaddr_t, vaddr_t));
void		uvm_unmap_detach __P((vm_map_entry_t,int));
int		uvm_unmap_remove __P((vm_map_t, vaddr_t, vaddr_t,
				      vm_map_entry_t *));

#endif /* _KERNEL */

/*
 * VM map locking operations:
 *
 *	These operations perform locking on the data portion of the
 *	map.
 *
 *	vm_map_lock_try: try to lock a map, failing if it is already locked.
 *
 *	vm_map_lock: acquire an exclusive (write) lock on a map.
 *
 *	vm_map_lock_read: acquire a shared (read) lock on a map.
 *
 *	vm_map_unlock: release an exclusive lock on a map.
 *
 *	vm_map_unlock_read: release a shared lock on a map.
 *
 *	vm_map_downgrade: downgrade an exclusive lock to a shared lock.
 *
 *	vm_map_upgrade: upgrade a shared lock to an exclusive lock.
 *
 *	vm_map_busy: mark a map as busy.
 *
 *	vm_map_unbusy: clear busy status on a map.
 *
 * Note that "intrsafe" maps use only exclusive, spin locks.  We simply
 * use the sleep lock's interlock for this.
 */

#ifdef _KERNEL
/* XXX: clean up later */
#include <sys/time.h>
#include <sys/proc.h>	/* for tsleep(), wakeup() */
#include <sys/systm.h>	/* for panic() */

static __inline boolean_t vm_map_lock_try __P((vm_map_t));
static __inline void vm_map_lock __P((vm_map_t));

static __inline boolean_t
vm_map_lock_try(map)
	vm_map_t map;
{
	boolean_t rv;

	if (map->flags & VM_MAP_INTRSAFE)
		rv = simple_lock_try(&map->lock.lk_interlock);
	else {
		simple_lock(&map->flags_lock);
		if (map->flags & VM_MAP_BUSY) {
			simple_unlock(&map->flags_lock);
			return (FALSE);
		}
		rv = (lockmgr(&map->lock, LK_EXCLUSIVE|LK_NOWAIT|LK_INTERLOCK,
		    &map->flags_lock) == 0);
	}

	if (rv)
		map->timestamp++;

	return (rv);
}

static __inline void
vm_map_lock(map)
	vm_map_t map;
{
	int error;

	if (map->flags & VM_MAP_INTRSAFE) {
		simple_lock(&map->lock.lk_interlock);
		return;
	}

 try_again:
	simple_lock(&map->flags_lock);
	while (map->flags & VM_MAP_BUSY) {
		map->flags |= VM_MAP_WANTLOCK;
		ltsleep(&map->flags, PVM, "vmmapbsy", 0, &map->flags_lock);
	}

	error = lockmgr(&map->lock, LK_EXCLUSIVE|LK_SLEEPFAIL|LK_INTERLOCK,
	    &map->flags_lock);

	if (error) {
#ifdef DIAGNOSTIC
		if (error != ENOLCK)
			panic("vm_map_lock: failed to get lock");
#endif
		goto try_again;
	}

	(map)->timestamp++;
#ifdef OSKIT			/* XXX */
	assert(map->lock.lk_lockholder == curproc->p_pid);
#endif
}

#ifdef DIAGNOSTIC
#define	vm_map_lock_read(map)						\
do {									\
	if (map->flags & VM_MAP_INTRSAFE)				\
		panic("vm_map_lock_read: intrsafe map");		\
	(void) lockmgr(&(map)->lock, LK_SHARED, NULL);			\
} while (0)
#else
#define	vm_map_lock_read(map)						\
	(void) lockmgr(&(map)->lock, LK_SHARED, NULL)
#endif

#define	vm_map_unlock(map)						\
do {									\
	if ((map)->flags & VM_MAP_INTRSAFE)				\
		simple_unlock(&(map)->lock.lk_interlock);		\
	else								\
		(void) lockmgr(&(map)->lock, LK_RELEASE, NULL);		\
} while (0)

#define	vm_map_unlock_read(map)						\
	(void) lockmgr(&(map)->lock, LK_RELEASE, NULL)

#define	vm_map_downgrade(map)						\
	(void) lockmgr(&(map)->lock, LK_DOWNGRADE, NULL)

#ifdef DIAGNOSTIC
#define	vm_map_upgrade(map)						\
do {									\
	if (lockmgr(&(map)->lock, LK_UPGRADE, NULL) != 0)		\
		panic("vm_map_upgrade: failed to upgrade lock");	\
} while (0)
#else
#define	vm_map_upgrade(map)						\
	(void) lockmgr(&(map)->lock, LK_UPGRADE, NULL)
#endif

#define	vm_map_busy(map)						\
do {									\
	simple_lock(&(map)->flags_lock);				\
	(map)->flags |= VM_MAP_BUSY;					\
	simple_unlock(&(map)->flags_lock);				\
} while (0)

#define	vm_map_unbusy(map)						\
do {									\
	int oflags;							\
									\
	simple_lock(&(map)->flags_lock);				\
	oflags = (map)->flags;						\
	(map)->flags &= ~(VM_MAP_BUSY|VM_MAP_WANTLOCK);			\
	simple_unlock(&(map)->flags_lock);				\
	if (oflags & VM_MAP_WANTLOCK)					\
		wakeup(&(map)->flags);					\
} while (0)
#endif /* _KERNEL */

/*
 *	Functions implemented as macros
 */
#define		vm_map_min(map)		((map)->min_offset)
#define		vm_map_max(map)		((map)->max_offset)
#define		vm_map_pmap(map)	((map)->pmap)

#endif /* _UVM_UVM_MAP_H_ */