Initial source

1 files changed, 741 insertions, 0 deletions

diff --git a/device/dev_pager.c b/device/dev_pager.c
new file mode 100644
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--- /dev/null
+++ b/device/dev_pager.c
@@ -0,0 +1,741 @@
+/* 
+ * Mach Operating System
+ * Copyright (c) 1993-1989 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.
+ */
+/*
+ *	Author: David B. Golub, Carnegie Mellon University
+ *	Date: 	3/89
+ *
+ * 	Device pager.
+ */
+#include <norma_vm.h>
+
+#include <mach/boolean.h>
+#include <mach/port.h>
+#include <mach/message.h>
+#include <mach/std_types.h>
+#include <mach/mach_types.h>
+
+#include <ipc/ipc_port.h>
+#include <ipc/ipc_space.h>
+
+#include <kern/queue.h>
+#include <kern/zalloc.h>
+#include <kern/kalloc.h>
+
+#include <vm/vm_page.h>
+#include <vm/vm_kern.h>
+
+#include <device/device_types.h>
+#include <device/ds_routines.h>
+#include <device/dev_hdr.h>
+#include <device/io_req.h>
+
+extern vm_offset_t	block_io_mmap();	/* dummy routine to allow
+						   mmap for block devices */
+
+/*
+ *	The device pager routines are called directly from the message
+ *	system (via mach_msg), and thus run in the kernel-internal
+ *	environment.  All ports are in internal form (ipc_port_t),
+ *	and must be correctly reference-counted in order to be saved
+ *	in other data structures.  Kernel routines may be called
+ *	directly.  Kernel types are used for data objects (tasks,
+ *	memory objects, ports).  The only IPC routines that may be
+ *	called are ones that masquerade as the kernel task (via
+ *	msg_send_from_kernel).
+ *
+ *	Port rights and references are maintained as follows:
+ *		Memory object port:
+ *			The device_pager task has all rights.
+ *		Memory object control port:
+ *			The device_pager task has only send rights.
+ *		Memory object name port:
+ *			The device_pager task has only send rights.
+ *			The name port is not even recorded.
+ *	Regardless how the object is created, the control and name
+ *	ports are created by the kernel and passed through the memory
+ *	management interface.
+ *
+ *	The device_pager assumes that access to its memory objects
+ *	will not be propagated to more that one host, and therefore
+ *	provides no consistency guarantees beyond those made by the
+ *	kernel.
+ *
+ *	In the event that more than one host attempts to use a device
+ *	memory object, the device_pager will only record the last set
+ *	of port names.  [This can happen with only one host if a new
+ *	mapping is being established while termination of all previous
+ *	mappings is taking place.]  Currently, the device_pager assumes
+ *	that its clients adhere to the initialization and termination
+ *	protocols in the memory management interface; otherwise, port
+ *	rights or out-of-line memory from erroneous messages may be
+ *	allowed to accumulate.
+ *
+ *	[The phrase "currently" has been used above to denote aspects of
+ *	the implementation that could be altered without changing the rest
+ *	of the basic documentation.]
+ */
+
+/*
+ * Basic device pager structure.
+ */
+struct dev_pager {
+	decl_simple_lock_data(, lock)	/* lock for reference count */
+	int		ref_count;	/* reference count */
+	int		client_count;	/* How many memory_object_create
+					 * calls have we received */
+	ipc_port_t	pager;		/* pager port */
+	ipc_port_t	pager_request;	/* Known request port */
+	ipc_port_t	pager_name;	/* Known name port */
+	mach_device_t	device;		/* Device handle */
+	int		type;		/* to distinguish */
+#define DEV_PAGER_TYPE	0
+#define CHAR_PAGER_TYPE	1
+	/* char pager specifics */
+	int		prot;
+	vm_size_t	size;
+};
+typedef struct dev_pager *dev_pager_t;
+#define	DEV_PAGER_NULL	((dev_pager_t)0)
+
+
+zone_t		dev_pager_zone;
+
+void dev_pager_reference(register dev_pager_t	ds)
+{
+	simple_lock(&ds->lock);
+	ds->ref_count++;
+	simple_unlock(&ds->lock);
+}
+
+void dev_pager_deallocate(register dev_pager_t	ds)
+{
+	simple_lock(&ds->lock);
+	if (--ds->ref_count > 0) {
+	    simple_unlock(&ds->lock);
+	    return;
+	}
+
+	simple_unlock(&ds->lock);
+	zfree(dev_pager_zone, (vm_offset_t)ds);
+}
+
+/*
+ * A hash table of ports for device_pager backed objects.
+ */
+
+#define	DEV_PAGER_HASH_COUNT		127
+
+struct dev_pager_entry {
+	queue_chain_t	links;
+	ipc_port_t	name;
+	dev_pager_t	pager_rec;
+};
+typedef struct dev_pager_entry *dev_pager_entry_t;
+
+queue_head_t	dev_pager_hashtable[DEV_PAGER_HASH_COUNT];
+zone_t		dev_pager_hash_zone;
+decl_simple_lock_data(,
+		dev_pager_hash_lock)
+
+#define	dev_pager_hash(name_port) \
+		(((natural_t)(name_port) & 0xffffff) % DEV_PAGER_HASH_COUNT)
+
+void dev_pager_hash_init(void)
+{
+	register int	i;
+	register vm_size_t	size;
+
+	size = sizeof(struct dev_pager_entry);
+	dev_pager_hash_zone = zinit(
+				size,
+				size * 1000,
+				PAGE_SIZE,
+				FALSE,
+				"dev_pager port hash");
+	for (i = 0; i < DEV_PAGER_HASH_COUNT; i++)
+	    queue_init(&dev_pager_hashtable[i]);
+	simple_lock_init(&dev_pager_hash_lock);
+}
+
+void dev_pager_hash_insert(
+	ipc_port_t	name_port,
+	dev_pager_t	rec)
+{
+	register dev_pager_entry_t new_entry;
+
+	new_entry = (dev_pager_entry_t) zalloc(dev_pager_hash_zone);
+	new_entry->name = name_port;
+	new_entry->pager_rec = rec;
+
+	simple_lock(&dev_pager_hash_lock);
+	queue_enter(&dev_pager_hashtable[dev_pager_hash(name_port)],
+			new_entry, dev_pager_entry_t, links);
+	simple_unlock(&dev_pager_hash_lock);
+}
+
+void dev_pager_hash_delete(ipc_port_t	name_port)
+{
+	register queue_t	bucket;
+	register dev_pager_entry_t	entry;
+
+	bucket = &dev_pager_hashtable[dev_pager_hash(name_port)];
+
+	simple_lock(&dev_pager_hash_lock);
+	for (entry = (dev_pager_entry_t)queue_first(bucket);
+	     !queue_end(bucket, &entry->links);
+	     entry = (dev_pager_entry_t)queue_next(&entry->links)) {
+	    if (entry->name == name_port) {
+		queue_remove(bucket, entry, dev_pager_entry_t, links);
+		break;
+	    }
+	}
+	simple_unlock(&dev_pager_hash_lock);
+	if (entry)
+	    zfree(dev_pager_hash_zone, (vm_offset_t)entry);
+}
+
+dev_pager_t dev_pager_hash_lookup(ipc_port_t	name_port)
+{
+	register queue_t	bucket;
+	register dev_pager_entry_t	entry;
+	register dev_pager_t	pager;
+
+	bucket = &dev_pager_hashtable[dev_pager_hash(name_port)];
+
+	simple_lock(&dev_pager_hash_lock);
+	for (entry = (dev_pager_entry_t)queue_first(bucket);
+	     !queue_end(bucket, &entry->links);
+	     entry = (dev_pager_entry_t)queue_next(&entry->links)) {
+	    if (entry->name == name_port) {
+		pager = entry->pager_rec;
+		dev_pager_reference(pager);
+		simple_unlock(&dev_pager_hash_lock);
+		return (pager);
+	    }
+	}
+	simple_unlock(&dev_pager_hash_lock);
+	return (DEV_PAGER_NULL);
+}
+
+kern_return_t	device_pager_setup(
+	mach_device_t	device,
+	int		prot,
+	vm_offset_t	offset,
+	vm_size_t	size,
+	mach_port_t	*pager)
+{
+	register dev_pager_t	d;
+
+	/*
+	 *	Verify the device is indeed mappable
+	 */
+	if (!device->dev_ops->d_mmap || (device->dev_ops->d_mmap == nomap))
+		return (D_INVALID_OPERATION);
+
+	/*
+	 *	Allocate a structure to hold the arguments
+	 *	and port to represent this object.
+	 */
+
+	d = dev_pager_hash_lookup((ipc_port_t)device);	/* HACK */
+	if (d != DEV_PAGER_NULL) {
+		*pager = (mach_port_t) ipc_port_make_send(d->pager);
+		dev_pager_deallocate(d);
+		return (D_SUCCESS);
+	}
+
+	d = (dev_pager_t) zalloc(dev_pager_zone);
+	if (d == DEV_PAGER_NULL)
+		return (KERN_RESOURCE_SHORTAGE);
+
+	simple_lock_init(&d->lock);
+	d->ref_count = 1;
+
+	/*
+	 * Allocate the pager port.
+	 */
+	d->pager = ipc_port_alloc_kernel();
+	if (d->pager == IP_NULL) {
+		dev_pager_deallocate(d);
+		return (KERN_RESOURCE_SHORTAGE);
+	}
+
+	d->client_count = 0;
+	d->pager_request = IP_NULL;
+	d->pager_name = IP_NULL;
+	d->device = device;
+	mach_device_reference(device);
+	d->prot = prot;
+	d->size = round_page(size);
+	if (device->dev_ops->d_mmap == block_io_mmap) {
+		d->type = DEV_PAGER_TYPE;
+	} else {
+		d->type = CHAR_PAGER_TYPE;
+	}
+
+	dev_pager_hash_insert(d->pager, d);
+	dev_pager_hash_insert((ipc_port_t)device, d);	/* HACK */
+
+	*pager = (mach_port_t) ipc_port_make_send(d->pager);
+	return (KERN_SUCCESS);
+}
+
+/*
+ *	Routine:	device_pager_release
+ *	Purpose:
+ *		Relinquish any references or rights that were
+ *		associated with the result of a call to
+ *		device_pager_setup.
+ */
+void	device_pager_release(memory_object_t	object)
+{
+	if (MACH_PORT_VALID(object))
+		ipc_port_release_send((ipc_port_t) object);
+}
+
+boolean_t	device_pager_debug = FALSE;
+
+boolean_t	device_pager_data_request_done();	/* forward */
+boolean_t	device_pager_data_write_done();		/* forward */
+
+
+kern_return_t	device_pager_data_request(
+	ipc_port_t	pager,
+	ipc_port_t	pager_request,
+	vm_offset_t	offset,
+	vm_size_t	length,
+	vm_prot_t	protection_required)
+{
+	register dev_pager_t	ds;
+
+#ifdef lint
+	protection_required++;
+#endif lint
+
+	if (device_pager_debug)
+		printf("(device_pager)data_request: pager=%d, offset=0x%x, length=0x%x\n",
+			pager, offset, length);
+
+	ds = dev_pager_hash_lookup((ipc_port_t)pager);
+	if (ds == DEV_PAGER_NULL)
+		panic("(device_pager)data_request: lookup failed");
+
+	if (ds->pager_request != pager_request)
+		panic("(device_pager)data_request: bad pager_request");
+
+	if (ds->type == CHAR_PAGER_TYPE) {
+	    register vm_object_t	object;
+	    vm_offset_t			device_map_page(void *,vm_offset_t);
+
+#if	NORMA_VM
+	    object = vm_object_lookup(pager);
+#else	NORMA_VM
+	    object = vm_object_lookup(pager_request);
+#endif	NORMA_VM
+	    if (object == VM_OBJECT_NULL) {
+		    (void) r_memory_object_data_error(pager_request,
+						      offset, length,
+						      KERN_FAILURE);
+		    dev_pager_deallocate(ds);
+		    return (KERN_SUCCESS);
+	    }
+
+	    vm_object_page_map(object,
+			       offset, length,
+			       device_map_page, (char *)ds);
+
+	    vm_object_deallocate(object);
+	}
+	else {
+	    register io_req_t		ior;
+	    register mach_device_t	device;
+	    io_return_t			result;
+
+	    panic("(device_pager)data_request: dev pager");
+	    
+	    device = ds->device;
+	    mach_device_reference(device);
+	    dev_pager_deallocate(ds);
+	    
+	    /*
+	     * Package the read for the device driver.
+	     */
+	    io_req_alloc(ior, 0);
+	    
+	    ior->io_device	= device;
+	    ior->io_unit	= device->dev_number;
+	    ior->io_op		= IO_READ | IO_CALL;
+	    ior->io_mode	= 0;
+	    ior->io_recnum	= offset / device->bsize;
+	    ior->io_data	= 0;		/* driver must allocate */
+	    ior->io_count	= length;
+	    ior->io_alloc_size	= 0;		/* no data allocated yet */
+	    ior->io_residual	= 0;
+	    ior->io_error	= 0;
+	    ior->io_done	= device_pager_data_request_done;
+	    ior->io_reply_port	= pager_request;
+	    ior->io_reply_port_type = MACH_MSG_TYPE_PORT_SEND;
+	    
+	    result = (*device->dev_ops->d_read)(device->dev_number, ior);
+	    if (result == D_IO_QUEUED)
+		return (KERN_SUCCESS);
+	    
+	    /*
+	     * Return by queuing IOR for io_done thread, to reply in
+	     * correct environment (kernel).
+	     */
+	    ior->io_error = result;
+	    iodone(ior);
+	}
+
+	dev_pager_deallocate(ds);
+
+	return (KERN_SUCCESS);
+}
+
+/*
+ * Always called by io_done thread.
+ */
+boolean_t device_pager_data_request_done(register io_req_t	ior)
+{
+	vm_offset_t	start_alloc, end_alloc;
+	vm_size_t	size_read;
+
+	if (ior->io_error == D_SUCCESS) {
+	    size_read = ior->io_count;
+	    if (ior->io_residual) {
+		if (device_pager_debug)
+		    printf("(device_pager)data_request_done: r: 0x%x\n",ior->io_residual);
+		bzero( (char *) (&ior->io_data[ior->io_count - 
+					       ior->io_residual]),
+		      (unsigned) ior->io_residual);
+	    }
+	} else {
+	    size_read = ior->io_count - ior->io_residual;
+	}
+
+	start_alloc = trunc_page((vm_offset_t)ior->io_data);
+	end_alloc   = start_alloc + round_page(ior->io_alloc_size);
+
+	if (ior->io_error == D_SUCCESS) {
+	    vm_map_copy_t copy;
+	    kern_return_t kr;
+
+	    kr = vm_map_copyin(kernel_map, (vm_offset_t)ior->io_data,
+				size_read, TRUE, &copy);
+	    if (kr != KERN_SUCCESS)
+		panic("device_pager_data_request_done");
+
+	    (void) r_memory_object_data_provided(
+					ior->io_reply_port,
+					ior->io_recnum * ior->io_device->bsize,
+					(vm_offset_t)copy,
+					size_read,
+					VM_PROT_NONE);
+	}
+	else {
+	    (void) r_memory_object_data_error(
+					ior->io_reply_port,
+					ior->io_recnum * ior->io_device->bsize,
+					(vm_size_t)ior->io_count,
+					ior->io_error);
+	}
+
+	(void)vm_deallocate(kernel_map,
+			    start_alloc,
+			    end_alloc - start_alloc);
+	mach_device_deallocate(ior->io_device);
+	return (TRUE);
+}
+
+kern_return_t device_pager_data_write(
+	ipc_port_t		pager,
+	ipc_port_t		pager_request,
+	register vm_offset_t	offset,
+	register pointer_t	addr,
+	vm_size_t		data_count)
+{
+	register dev_pager_t	ds;
+	register mach_device_t	device;
+	register io_req_t	ior;
+	kern_return_t		result;
+
+	panic("(device_pager)data_write: called");
+
+	ds = dev_pager_hash_lookup((ipc_port_t)pager);
+	if (ds == DEV_PAGER_NULL)
+		panic("(device_pager)data_write: lookup failed");
+
+	if (ds->pager_request != pager_request)
+		panic("(device_pager)data_write: bad pager_request");
+
+	if (ds->type == CHAR_PAGER_TYPE)
+		panic("(device_pager)data_write: char pager");
+
+	device = ds->device;
+	mach_device_reference(device);
+	dev_pager_deallocate(ds);
+
+	/*
+	 * Package the write request for the device driver.
+	 */
+	io_req_alloc(ior, data_count);
+
+	ior->io_device		= device;
+	ior->io_unit		= device->dev_number;
+	ior->io_op		= IO_WRITE | IO_CALL;
+	ior->io_mode		= 0;
+	ior->io_recnum		= offset / device->bsize;
+	ior->io_data		= (io_buf_ptr_t)addr;
+	ior->io_count		= data_count;
+	ior->io_alloc_size	= data_count;	/* amount to deallocate */
+	ior->io_residual	= 0;
+	ior->io_error		= 0;
+	ior->io_done		= device_pager_data_write_done;
+	ior->io_reply_port	= IP_NULL;
+
+	result = (*device->dev_ops->d_write)(device->dev_number, ior);
+
+	if (result != D_IO_QUEUED) {
+	    device_write_dealloc(ior);
+	    io_req_free((vm_offset_t)ior);
+	    mach_device_deallocate(device);
+	}
+
+	return (KERN_SUCCESS);
+}
+
+boolean_t device_pager_data_write_done(ior)
+	register io_req_t	ior;
+{
+	device_write_dealloc(ior);
+	mach_device_deallocate(ior->io_device);
+
+	return (TRUE);
+}
+
+kern_return_t device_pager_copy(
+	ipc_port_t		pager,
+	ipc_port_t		pager_request,
+	register vm_offset_t	offset,
+	register vm_size_t	length,
+	ipc_port_t		new_pager)
+{
+	panic("(device_pager)copy: called");
+}
+
+kern_return_t
+device_pager_supply_completed(
+	ipc_port_t pager,
+	ipc_port_t pager_request,
+	vm_offset_t offset,
+	vm_size_t length,
+	kern_return_t result,
+	vm_offset_t error_offset)
+{
+	panic("(device_pager)supply_completed: called");
+}
+
+kern_return_t
+device_pager_data_return(
+	ipc_port_t		pager,
+	ipc_port_t		pager_request,
+	vm_offset_t		offset,
+	register pointer_t	addr,
+	vm_size_t		data_cnt,
+	boolean_t		dirty,
+	boolean_t		kernel_copy)
+{
+	panic("(device_pager)data_return: called");
+}
+
+kern_return_t
+device_pager_change_completed(
+	ipc_port_t pager,
+	boolean_t may_cache,
+	memory_object_copy_strategy_t copy_strategy)
+{
+	panic("(device_pager)change_completed: called");
+}
+
+/*
+ *	The mapping function takes a byte offset, but returns
+ *	a machine-dependent page frame number.  We convert
+ *	that into something that the pmap module will
+ *	accept later.
+ */
+vm_offset_t device_map_page(
+	void		*dsp,
+	vm_offset_t	offset)
+{
+	register dev_pager_t	ds = (dev_pager_t) dsp;
+
+	return pmap_phys_address(
+		   (*(ds->device->dev_ops->d_mmap))
+			(ds->device->dev_number, offset, ds->prot));
+}
+
+kern_return_t device_pager_init_pager(
+	ipc_port_t	pager,
+	ipc_port_t	pager_request,
+	ipc_port_t	pager_name,
+	vm_size_t	pager_page_size)
+{
+	register dev_pager_t	ds;
+
+	if (device_pager_debug)
+		printf("(device_pager)init: pager=%d, request=%d, name=%d\n",
+		       pager, pager_request, pager_name);
+
+	assert(pager_page_size == PAGE_SIZE);
+	assert(IP_VALID(pager_request));
+	assert(IP_VALID(pager_name));
+
+	ds = dev_pager_hash_lookup(pager);
+	assert(ds != DEV_PAGER_NULL);
+
+	assert(ds->client_count == 0);
+	assert(ds->pager_request == IP_NULL);
+	assert(ds->pager_name == IP_NULL);
+
+	ds->client_count = 1;
+
+	/*
+	 * We save the send rights for the request and name ports.
+	 */
+
+	ds->pager_request = pager_request;
+	ds->pager_name = pager_name;
+
+	if (ds->type == CHAR_PAGER_TYPE) {
+	    /*
+	     * Reply that the object is ready
+	     */
+	    (void) r_memory_object_set_attributes(pager_request,
+						TRUE,	/* ready */
+						FALSE,	/* do not cache */
+						MEMORY_OBJECT_COPY_NONE);
+	} else {
+	    (void) r_memory_object_set_attributes(pager_request,
+						TRUE,	/* ready */
+						TRUE,	/* cache */
+						MEMORY_OBJECT_COPY_DELAY);
+	}
+
+	dev_pager_deallocate(ds);
+	return (KERN_SUCCESS);
+}
+
+kern_return_t device_pager_terminate(
+	ipc_port_t	pager,
+	ipc_port_t	pager_request,
+	ipc_port_t	pager_name)
+{
+	register dev_pager_t	ds;
+
+	assert(IP_VALID(pager_request));
+	assert(IP_VALID(pager_name));
+
+	ds = dev_pager_hash_lookup(pager);
+	assert(ds != DEV_PAGER_NULL);
+
+	assert(ds->client_count == 1);
+	assert(ds->pager_request == pager_request);
+	assert(ds->pager_name == pager_name);
+
+	dev_pager_hash_delete(ds->pager);
+	dev_pager_hash_delete((ipc_port_t)ds->device);	/* HACK */
+	mach_device_deallocate(ds->device);
+
+	/* release the send rights we have saved from the init call */
+
+	ipc_port_release_send(pager_request);
+	ipc_port_release_send(pager_name);
+
+	/* release the naked receive rights we just acquired */
+
+	ipc_port_release_receive(pager_request);
+	ipc_port_release_receive(pager_name);
+
+	/* release the kernel's receive right for the pager port */
+
+	ipc_port_dealloc_kernel(pager);
+
+	/* once for ref from lookup, once to make it go away */
+	dev_pager_deallocate(ds);
+	dev_pager_deallocate(ds);
+
+	return (KERN_SUCCESS);
+}
+
+kern_return_t device_pager_data_unlock(
+	ipc_port_t memory_object,
+	ipc_port_t memory_control_port,
+	vm_offset_t offset,
+	vm_size_t length,
+	vm_prot_t desired_access)
+{
+#ifdef	lint
+	memory_object++; memory_control_port++; offset++; length++; desired_access++;
+#endif	lint
+
+	panic("(device_pager)data_unlock: called");
+	return (KERN_FAILURE);
+}
+
+kern_return_t device_pager_lock_completed(
+	ipc_port_t	memory_object,
+	ipc_port_t	pager_request_port,
+	vm_offset_t	offset,
+	vm_size_t	length)
+{
+#ifdef	lint
+	memory_object++; pager_request_port++; offset++; length++;
+#endif	lint
+
+	panic("(device_pager)lock_completed: called");
+	return (KERN_FAILURE);
+}
+
+void device_pager_init(void)
+{
+	register vm_size_t	size;
+
+	/*
+	 * Initialize zone of paging structures.
+	 */
+	size = sizeof(struct dev_pager);
+	dev_pager_zone = zinit(size,
+				(vm_size_t) size * 1000,
+				PAGE_SIZE,
+				FALSE,
+				"device pager structures");
+
+	/*
+	 *	Initialize the name port hashing stuff.
+	 */
+	dev_pager_hash_init();
+}