Add IPC functions that allow user to manipulate with memory advice.

* include/mach/mach_types.defs (vm_advice_t): New type definition.

* include/mach/mach.defs (vm_advise): New RPC definition.
(memory_object_set_advice): Likewise.
(memory_object_get_advice): Likewise.

* kern/ipc_mig.c (syscall_vm_advice): New function. This is optimization
function for RPC that is processed by kernel.

* kern/syscall_sw.c (syscall_vm_advice): Add function prototype.
(mach_trap_table): Add syscall_vm_advice to trap table.

* vm/memory_object.c (memory_object_set_advice): New function. Sets memory
advice for memory object.
(memory_object_get_advice): New function. Returns memory advice of memory
object.

* vm/vm_user.c (vm_advise): New function. Wrapper for vm_map_advice.

* vm/vm_map.h (vm_map_advice): Add function prototype.

* vm/vm_map.c (vm_map_advice): New function. Sets memory advice for memory
range.

4 files changed, 112 insertions, 0 deletions

diff --git a/vm/memory_object.c b/vm/memory_object.c
index e281c6a3..090b58eb 100644
--- a/vm/memory_object.c
+++ b/vm/memory_object.c
@@ -1037,6 +1037,49 @@ kern_return_t	memory_object_get_attributes(object, object_ready,
 	return(KERN_SUCCESS);
 }
 
+kern_return_t
+memory_object_set_advice(vm_object_t object, vm_advice_t advice)
+{
+	if (object == VM_OBJECT_NULL)
+		return(KERN_INVALID_ARGUMENT);
+
+	switch(advice) {
+		case VM_ADVICE_DEFAULT:
+		case VM_ADVICE_RANDOM:
+		case VM_ADVICE_SEQUENTIAL:
+		case VM_ADVICE_NORMAL:
+		case VM_ADVICE_KEEP:
+			break;
+		default:
+			vm_object_deallocate(object);
+			return(KERN_INVALID_ARGUMENT);
+	}
+
+	vm_object_lock(object);
+	if (advice != VM_ADVICE_KEEP)
+		object->advice = advice;
+	vm_object_unlock(object);
+
+	vm_object_deallocate(object);
+
+	return(KERN_SUCCESS);
+}
+
+kern_return_t
+memory_object_get_advice(vm_object_t object, vm_advice_t *advice)
+{
+	if (object == VM_OBJECT_NULL)
+		return(KERN_INVALID_ARGUMENT);
+
+	vm_object_lock(object);
+	*advice = object->advice;
+	vm_object_unlock(object);
+
+	vm_object_deallocate(object);
+
+	return(KERN_SUCCESS);
+}
+
 /*
  *	If successful, consumes the supplied naked send right.
  */
diff --git a/vm/vm_map.c b/vm/vm_map.c
index 22fe0eae..0afaff29 100644
--- a/vm/vm_map.c
+++ b/vm/vm_map.c
@@ -1346,6 +1346,46 @@ kern_return_t vm_map_inherit(map, start, end, new_inheritance)
 }
 
 /*
+ *	vm_map_advise:
+ *
+ *	Sets the page fault advice of the specified
+ *	address range in the target map.  Advice
+ *	affects how the page fault will be
+ *	handled at the time of vm_fault.
+ */
+kern_return_t
+vm_map_advise(vm_map_t map, vm_offset_t address,
+	      vm_size_t length, vm_advice_t advice)
+{
+	register vm_map_entry_t	entry;
+	vm_map_entry_t	temp_entry;
+	vm_offset_t	end = address + length;
+
+	vm_map_lock(map);
+
+	VM_MAP_RANGE_CHECK(map, address, end);
+
+	if (vm_map_lookup_entry(map, address, &temp_entry)) {
+		entry = temp_entry;
+		vm_map_clip_start(map, entry, address);
+	}
+	else
+		entry = temp_entry->vme_next;
+
+	while ((entry != vm_map_to_entry(map))
+		&& (entry->vme_start < end)) {
+		vm_map_clip_end(map, entry, end);
+
+		entry->advice = advice;
+
+		entry = entry->vme_next;
+	}
+
+	vm_map_unlock(map);
+	return(KERN_SUCCESS);
+}
+
+/*
  *	vm_map_pageable_common:
  *
  *	Sets the pageability of the specified address
diff --git a/vm/vm_map.h b/vm/vm_map.h
index af7588ba..96c0bcbf 100644
--- a/vm/vm_map.h
+++ b/vm/vm_map.h
@@ -397,6 +397,9 @@ extern kern_return_t	vm_map_protect(vm_map_t, vm_offset_t, vm_offset_t,
 /* Change inheritance */
 extern kern_return_t	vm_map_inherit(vm_map_t, vm_offset_t, vm_offset_t,
 				       vm_inherit_t);
+/* Change page fault policy */
+extern kern_return_t	vm_map_advise(vm_map_t, vm_offset_t, vm_size_t,
+				      vm_advice_t);
 
 /* Debugging: print a map */
 extern void		vm_map_print(vm_map_t);
diff --git a/vm/vm_user.c b/vm/vm_user.c
index 59c2a36e..c5530a69 100644
--- a/vm/vm_user.c
+++ b/vm/vm_user.c
@@ -171,6 +171,32 @@ kern_return_t vm_protect(map, start, size, set_maximum, new_protection)
 			      set_maximum));
 }
 
+
+/*
+ *	vm_advise sets page fault handling policy of the specified range
+ *	in the specified map.
+ */
+
+kern_return_t
+vm_advise(vm_map_t map, vm_offset_t address,
+	  vm_size_t length, vm_advice_t advice)
+{
+	if (map == VM_MAP_NULL)
+		return(KERN_INVALID_ARGUMENT);
+
+	switch(advice) {
+		case VM_ADVICE_DEFAULT:
+		case VM_ADVICE_RANDOM:
+		case VM_ADVICE_SEQUENTIAL:
+		case VM_ADVICE_NORMAL:
+			break;
+		default:
+			return(KERN_INVALID_ARGUMENT);
+	}
+
+	return(vm_map_advise(map, address, length, advice));
+}
+
 kern_return_t vm_statistics(map, stat)
 	vm_map_t	map;
 	vm_statistics_data_t	*stat;