/*
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
 * All Rights Reserved.
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 *	File:	vm/vm_user.c
 *	Author:	Avadis Tevanian, Jr., Michael Wayne Young
 *
 *	User-exported virtual memory functions.
 */

#include <mach/boolean.h>
#include <mach/kern_return.h>
#include <mach/mach_types.h>	/* to get vm_address_t */
#include <mach/memory_object.h>
#include <mach/std_types.h>	/* to get pointer_t */
#include <mach/vm_attributes.h>
#include <mach/vm_param.h>
#include <mach/vm_statistics.h>
#include <mach/vm_cache_statistics.h>
#include <mach/vm_sync.h>
#include <kern/host.h>
#include <kern/task.h>
#include <kern/mach.server.h>
#include <vm/vm_fault.h>
#include <vm/vm_kern.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/memory_object_proxy.h>
#include <vm/vm_page.h>



vm_statistics_data_t	vm_stat;

/*
 *	vm_allocate allocates "zero fill" memory in the specfied
 *	map.
 */
kern_return_t vm_allocate(
	vm_map_t	map,
	vm_offset_t	*addr,
	vm_size_t	size,
	boolean_t	anywhere)
{
	kern_return_t	result;

	if (map == VM_MAP_NULL)
		return(KERN_INVALID_ARGUMENT);
	if (size == 0) {
		*addr = 0;
		return(KERN_SUCCESS);
	}

	if (anywhere)
		*addr = vm_map_min(map);
	else
		*addr = trunc_page(*addr);
	size = round_page(size);

	result = vm_map_enter(
			map,
			addr,
			size,
			(vm_offset_t)0,
			anywhere,
			VM_OBJECT_NULL,
			(vm_offset_t)0,
			FALSE,
			VM_PROT_DEFAULT,
			VM_PROT_ALL,
			VM_INHERIT_DEFAULT);

	return(result);
}

/*
 *	vm_deallocate deallocates the specified range of addresses in the
 *	specified address map.
 */
kern_return_t vm_deallocate(
	vm_map_t		map,
	vm_offset_t		start,
	vm_size_t		size)
{
	if (map == VM_MAP_NULL)
		return(KERN_INVALID_ARGUMENT);

	if (size == (vm_offset_t) 0)
		return(KERN_SUCCESS);

	return(vm_map_remove(map, trunc_page(start), round_page(start+size)));
}

/*
 *	vm_inherit sets the inheritance of the specified range in the
 *	specified map.
 */
kern_return_t vm_inherit(
	vm_map_t		map,
	vm_offset_t		start,
	vm_size_t		size,
	vm_inherit_t		new_inheritance)
{
	if (map == VM_MAP_NULL)
		return(KERN_INVALID_ARGUMENT);

        switch (new_inheritance) {
        case VM_INHERIT_NONE:
        case VM_INHERIT_COPY:
        case VM_INHERIT_SHARE:
                break;
        default:
                return(KERN_INVALID_ARGUMENT);
        }

	/*Check if range includes projected buffer;
	  user is not allowed direct manipulation in that case*/
	if (projected_buffer_in_range(map, start, start+size))
		return(KERN_INVALID_ARGUMENT);

	return(vm_map_inherit(map,
			      trunc_page(start),
			      round_page(start+size),
			      new_inheritance));
}

/*
 *	vm_protect sets the protection of the specified range in the
 *	specified map.
 */

kern_return_t vm_protect(
	vm_map_t		map,
	vm_offset_t		start,
	vm_size_t		size,
	boolean_t		set_maximum,
	vm_prot_t		new_protection)
{
	if ((map == VM_MAP_NULL) ||
		(new_protection & ~(VM_PROT_ALL|VM_PROT_NOTIFY)))
		return(KERN_INVALID_ARGUMENT);

	/*Check if range includes projected buffer;
	  user is not allowed direct manipulation in that case*/
	if (projected_buffer_in_range(map, start, start+size))
		return(KERN_INVALID_ARGUMENT);

	return(vm_map_protect(map,
			      trunc_page(start),
			      round_page(start+size),
			      new_protection,
			      set_maximum));
}

kern_return_t vm_statistics(
	vm_map_t		map,
	vm_statistics_data_t	*stat)
{
	if (map == VM_MAP_NULL)
		return(KERN_INVALID_ARGUMENT);

	*stat = vm_stat;

	stat->pagesize = PAGE_SIZE;
	stat->free_count = vm_page_mem_free();
	stat->active_count = vm_page_active_count;
	stat->inactive_count = vm_page_inactive_count;
	stat->wire_count = vm_page_wire_count;

	return(KERN_SUCCESS);
}

kern_return_t vm_cache_statistics(
	vm_map_t			map,
	vm_cache_statistics_data_t	*stats)
{
	if (map == VM_MAP_NULL)
		return KERN_INVALID_ARGUMENT;

	stats->cache_object_count = vm_object_external_count;
	stats->cache_count = vm_object_external_pages;

	/* XXX Not implemented yet */
	stats->active_tmp_count = 0;
	stats->inactive_tmp_count = 0;
	stats->active_perm_count = 0;
	stats->inactive_perm_count = 0;
	stats->dirty_count = 0;
	stats->laundry_count = 0;
	stats->writeback_count = 0;
	stats->slab_count = 0;
	stats->slab_reclaim_count = 0;
	return KERN_SUCCESS;
}

/*
 * Handle machine-specific attributes for a mapping, such
 * as cachability, migrability, etc.
 */
kern_return_t vm_machine_attribute(
	vm_map_t	map,
	vm_address_t	address,
	vm_size_t	size,
	vm_machine_attribute_t	attribute,
	vm_machine_attribute_val_t* value)		/* IN/OUT */
{
	if (map == VM_MAP_NULL)
		return(KERN_INVALID_ARGUMENT);

	/*Check if range includes projected buffer;
	  user is not allowed direct manipulation in that case*/
	if (projected_buffer_in_range(map, address, address+size))
		return(KERN_INVALID_ARGUMENT);

	return vm_map_machine_attribute(map, address, size, attribute, value);
}

kern_return_t vm_read(
	vm_map_t	map,
	vm_address_t	address,
	vm_size_t	size,
	pointer_t	*data,
	mach_msg_type_number_t	*data_size)
{
	kern_return_t	error;
	vm_map_copy_t	ipc_address;

	if (map == VM_MAP_NULL)
		return(KERN_INVALID_ARGUMENT);

	if ((error = vm_map_copyin(map,
				address,
				size,
				FALSE,	/* src_destroy */
				&ipc_address)) == KERN_SUCCESS) {
		*data = (pointer_t) ipc_address;
		*data_size = size;
	}
	return(error);
}

kern_return_t vm_write(
	vm_map_t	map,
	vm_address_t	address,
	pointer_t	data,
	mach_msg_type_number_t	size)
{
	if (map == VM_MAP_NULL)
		return KERN_INVALID_ARGUMENT;

	return vm_map_copy_overwrite(map, address, (vm_map_copy_t) data,
				     FALSE /* interruptible XXX */);
}

kern_return_t vm_copy(
	vm_map_t	map,
	vm_address_t	source_address,
	vm_size_t	size,
	vm_address_t	dest_address)
{
	vm_map_copy_t copy;
	kern_return_t kr;

	if (map == VM_MAP_NULL)
		return KERN_INVALID_ARGUMENT;

	kr = vm_map_copyin(map, source_address, size,
			   FALSE, &copy);
	if (kr != KERN_SUCCESS)
		return kr;

	kr = vm_map_copy_overwrite(map, dest_address, copy,
				   FALSE /* interruptible XXX */);
	if (kr != KERN_SUCCESS) {
		vm_map_copy_discard(copy);
		return kr;
	}

	return KERN_SUCCESS;
}


/*
 *	Routine:	vm_map
 */
kern_return_t vm_map(
	vm_map_t	target_map,
	vm_offset_t	*address,
	vm_size_t	size,
	vm_offset_t	mask,
	boolean_t	anywhere,
	ipc_port_t	memory_object,
	vm_offset_t	offset,
	boolean_t	copy,
	vm_prot_t	cur_protection,
	vm_prot_t	max_protection,
	vm_inherit_t	inheritance)
{
	vm_object_t	object;
	kern_return_t	result;

	if ((target_map == VM_MAP_NULL) ||
	    (cur_protection & ~VM_PROT_ALL) ||
	    (max_protection & ~VM_PROT_ALL))
		return(KERN_INVALID_ARGUMENT);

        switch (inheritance) {
        case VM_INHERIT_NONE:
        case VM_INHERIT_COPY:
        case VM_INHERIT_SHARE:
                break;
        default:
                return(KERN_INVALID_ARGUMENT);
        }

	if (size == 0)
		return KERN_INVALID_ARGUMENT;

	*address = trunc_page(*address);
	size = round_page(size);

	if (!IP_VALID(memory_object)) {
		object = VM_OBJECT_NULL;
		offset = 0;
		copy = FALSE;
	} else if ((object = vm_object_enter(memory_object, size, FALSE))
			== VM_OBJECT_NULL)
	  {
	    ipc_port_t real_memobj;
	    vm_prot_t prot;
	    vm_offset_t start;
	    vm_offset_t len;

	    result = memory_object_proxy_lookup (memory_object, &real_memobj,
						 &prot, &start, &len);
	    if (result != KERN_SUCCESS)
	      return result;

           if (!copy)
             {
		/* Reduce the allowed access to the memory object.  */
		max_protection &= prot;
		cur_protection &= prot;
             }
           else
             {
               /* Disallow making a copy unless the proxy allows reading.  */
               if (!(prot & VM_PROT_READ))
                 return KERN_PROTECTION_FAILURE;
             }

	    /* Reduce the allowed range */
	    if ((start + offset + size) > (start + len))
	      return KERN_INVALID_ARGUMENT;

	    offset += start;

	    if ((object = vm_object_enter(real_memobj, size, FALSE))
		== VM_OBJECT_NULL)
	      return KERN_INVALID_ARGUMENT;
	  }

	/*
	 *	Perform the copy if requested
	 */

	if (copy) {
		vm_object_t	new_object;
		vm_offset_t	new_offset;

		result = vm_object_copy_strategically(object, offset, size,
				&new_object, &new_offset,
				&copy);

		/*
		 *	Throw away the reference to the
		 *	original object, as it won't be mapped.
		 */

		vm_object_deallocate(object);

		if (result != KERN_SUCCESS)
			return (result);

		object = new_object;
		offset = new_offset;
	}

	if ((result = vm_map_enter(target_map,
				address, size, mask, anywhere,
				object, offset,
				copy,
				cur_protection, max_protection, inheritance
				)) != KERN_SUCCESS)
		vm_object_deallocate(object);
	return(result);
}

/*
 *	Specify that the range of the virtual address space
 *	of the target task must not cause page faults for
 *	the indicated accesses.
 *
 *	[ To unwire the pages, specify VM_PROT_NONE. ]
 */
kern_return_t vm_wire(port, map, start, size, access)
	const ipc_port_t	port;
	vm_map_t		map;
	vm_offset_t		start;
	vm_size_t		size;
	vm_prot_t		access;
{
	boolean_t priv;

	if (!IP_VALID(port))
		return KERN_INVALID_HOST;

	ip_lock(port);
	if (!ip_active(port) ||
		  (ip_kotype(port) != IKOT_HOST_PRIV
		&& ip_kotype(port) != IKOT_HOST))
	{
		ip_unlock(port);
		return KERN_INVALID_HOST;
	}

	priv = ip_kotype(port) == IKOT_HOST_PRIV;
	ip_unlock(port);

	if (map == VM_MAP_NULL)
		return KERN_INVALID_TASK;

	if (access & ~VM_PROT_ALL)
		return KERN_INVALID_ARGUMENT;

	/*Check if range includes projected buffer;
	  user is not allowed direct manipulation in that case*/
	if (projected_buffer_in_range(map, start, start+size))
		return(KERN_INVALID_ARGUMENT);

	/* TODO: make it tunable */
	if (!priv && access != VM_PROT_NONE && map->size_wired + size > 65536)
		return KERN_NO_ACCESS;

	return vm_map_pageable(map, trunc_page(start), round_page(start+size),
			       access, TRUE, TRUE);
}

kern_return_t vm_wire_all(const ipc_port_t port, vm_map_t map, vm_wire_t flags)
{
	if (!IP_VALID(port))
		return KERN_INVALID_HOST;

	ip_lock(port);

	if (!ip_active(port)
	    || (ip_kotype(port) != IKOT_HOST_PRIV)) {
		ip_unlock(port);
		return KERN_INVALID_HOST;
	}

	ip_unlock(port);

	if (map == VM_MAP_NULL) {
		return KERN_INVALID_TASK;
	}

	if (flags & ~VM_WIRE_ALL) {
		return KERN_INVALID_ARGUMENT;
	}

	/*Check if range includes projected buffer;
	  user is not allowed direct manipulation in that case*/
	if (projected_buffer_in_range(map, map->min_offset, map->max_offset)) {
		return KERN_INVALID_ARGUMENT;
	}

	return vm_map_pageable_all(map, flags);
}

/*
 *	vm_object_sync synchronizes out pages from the memory object to its
 *	memory manager, if any.
 */
kern_return_t vm_object_sync(
	vm_object_t		object,
	vm_offset_t		offset,
	vm_size_t		size,
	boolean_t		should_flush,
	boolean_t		should_return,
	boolean_t		should_iosync)
{
	if (object == VM_OBJECT_NULL)
		return KERN_INVALID_ARGUMENT;

	/* FIXME: we should rather introduce an internal function, e.g.
	   vm_object_update, rather than calling memory_object_lock_request.  */
	vm_object_reference(object);

	/* This is already always synchronous for now.  */
	(void) should_iosync;

	size = round_page(offset + size) - trunc_page(offset);
	offset = trunc_page(offset);

	return  memory_object_lock_request(object, offset, size,
					   should_return ?
						MEMORY_OBJECT_RETURN_ALL :
						MEMORY_OBJECT_RETURN_NONE,
					   should_flush,
					   VM_PROT_NO_CHANGE,
					   NULL, 0);
}

/*
 *	vm_msync synchronizes out pages from the map to their memory manager,
 *	if any.
 */
kern_return_t vm_msync(
	vm_map_t		map,
	vm_address_t		address,
	vm_size_t		size,
	vm_sync_t		sync_flags)
{
	if (map == VM_MAP_NULL)
		return KERN_INVALID_ARGUMENT;

	return vm_map_msync(map, (vm_offset_t) address, size, sync_flags);
}

/*
 *	vm_allocate_contiguous allocates "zero fill" physical memory and maps
 *	it into in the specfied map.
 */
/* TODO: respect physical alignment (palign)
 *       and minimum physical address (pmin)
 */
kern_return_t vm_allocate_contiguous(
	host_t			host_priv,
	vm_map_t		map,
	vm_address_t		*result_vaddr,
	rpc_phys_addr_t		*result_paddr,
	vm_size_t		size,
	rpc_phys_addr_t		pmin,
	rpc_phys_addr_t		pmax,
	rpc_phys_addr_t		palign)
{
	vm_size_t		alloc_size;
	unsigned int		npages;
	unsigned int		i;
	unsigned int		order;
	unsigned int		selector;
	vm_page_t		pages;
	vm_object_t		object;
	kern_return_t		kr;
	vm_address_t		vaddr;

	if (host_priv == HOST_NULL)
		return KERN_INVALID_HOST;

	if (map == VM_MAP_NULL)
		return KERN_INVALID_TASK;

	/* FIXME */
	if (pmin != 0)
		return KERN_INVALID_ARGUMENT;

	if (palign == 0)
		palign = PAGE_SIZE;

	/* FIXME */
	if (palign != PAGE_SIZE)
		return KERN_INVALID_ARGUMENT;

	selector = VM_PAGE_SEL_DMA;
	if (pmax > VM_PAGE_DMA_LIMIT)
#ifdef VM_PAGE_DMA32_LIMIT
		selector = VM_PAGE_SEL_DMA32;
	if (pmax > VM_PAGE_DMA32_LIMIT)
#endif
		selector = VM_PAGE_SEL_DIRECTMAP;
	if (pmax > VM_PAGE_DIRECTMAP_LIMIT)
		selector = VM_PAGE_SEL_HIGHMEM;

	size = vm_page_round(size);

	if (size == 0)
		return KERN_INVALID_ARGUMENT;

	object = vm_object_allocate(size);

	if (object == NULL)
		return KERN_RESOURCE_SHORTAGE;

	/*
	 * XXX The page allocator returns blocks with a power-of-two size.
	 * The requested size may not be a power-of-two, requiring some
	 * work to release back the pages that aren't needed.
	 */
	order = vm_page_order(size);
	alloc_size = (1 << (order + PAGE_SHIFT));
	npages = vm_page_atop(alloc_size);

	pages = vm_page_grab_contig(alloc_size, selector);

	if (pages == NULL) {
		vm_object_deallocate(object);
		return KERN_RESOURCE_SHORTAGE;
	}

	vm_object_lock(object);
	vm_page_lock_queues();

	for (i = 0; i < vm_page_atop(size); i++) {
		/*
		 * XXX We can safely handle contiguous pages as an array,
		 * but this relies on knowing the implementation of the
		 * page allocator.
		 */
		pages[i].busy = FALSE;
		vm_page_insert(&pages[i], object, vm_page_ptoa(i));
		vm_page_wire(&pages[i]);
	}

	vm_page_unlock_queues();
	vm_object_unlock(object);

	for (i = vm_page_atop(size); i < npages; i++) {
		vm_page_release(&pages[i], FALSE, FALSE);
	}

	vaddr = 0;
	kr = vm_map_enter(map, &vaddr, size, 0, TRUE, object, 0, FALSE,
			  VM_PROT_READ | VM_PROT_WRITE,
			  VM_PROT_READ | VM_PROT_WRITE, VM_INHERIT_DEFAULT);

	if (kr != KERN_SUCCESS) {
		vm_object_deallocate(object);
		return kr;
	}

	kr = vm_map_pageable(map, vaddr, vaddr + size,
			     VM_PROT_READ | VM_PROT_WRITE,
			     TRUE, TRUE);

	if (kr != KERN_SUCCESS) {
		vm_map_remove(map, vaddr, vaddr + size);
		return kr;
	}

	*result_vaddr = vaddr;
	*result_paddr = pages->phys_addr;

	return KERN_SUCCESS;
}