linux-stable-rt/drivers/char/drm/drm_scatter.c

239 lines
6.1 KiB
C

/**
* \file drm_scatter.h
* IOCTLs to manage scatter/gather memory
*
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Mon Dec 18 23:20:54 2000 by gareth@valinux.com
*
* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include <linux/config.h>
#include <linux/vmalloc.h>
#include "drmP.h"
#define DEBUG_SCATTER 0
void drm_sg_cleanup( drm_sg_mem_t *entry )
{
struct page *page;
int i;
for ( i = 0 ; i < entry->pages ; i++ ) {
page = entry->pagelist[i];
if ( page )
ClearPageReserved( page );
}
vfree( entry->virtual );
drm_free( entry->busaddr,
entry->pages * sizeof(*entry->busaddr),
DRM_MEM_PAGES );
drm_free( entry->pagelist,
entry->pages * sizeof(*entry->pagelist),
DRM_MEM_PAGES );
drm_free( entry,
sizeof(*entry),
DRM_MEM_SGLISTS );
}
#ifdef _LP64
# define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1)))
#else
# define ScatterHandle(x) (unsigned int)(x)
#endif
int drm_sg_alloc( struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg )
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->head->dev;
drm_scatter_gather_t __user *argp = (void __user *)arg;
drm_scatter_gather_t request;
drm_sg_mem_t *entry;
unsigned long pages, i, j;
DRM_DEBUG( "%s\n", __FUNCTION__ );
if (!drm_core_check_feature(dev, DRIVER_SG))
return -EINVAL;
if ( dev->sg )
return -EINVAL;
if ( copy_from_user( &request, argp, sizeof(request) ) )
return -EFAULT;
entry = drm_alloc( sizeof(*entry), DRM_MEM_SGLISTS );
if ( !entry )
return -ENOMEM;
memset( entry, 0, sizeof(*entry) );
pages = (request.size + PAGE_SIZE - 1) / PAGE_SIZE;
DRM_DEBUG( "sg size=%ld pages=%ld\n", request.size, pages );
entry->pages = pages;
entry->pagelist = drm_alloc( pages * sizeof(*entry->pagelist),
DRM_MEM_PAGES );
if ( !entry->pagelist ) {
drm_free( entry, sizeof(*entry), DRM_MEM_SGLISTS );
return -ENOMEM;
}
memset(entry->pagelist, 0, pages * sizeof(*entry->pagelist));
entry->busaddr = drm_alloc( pages * sizeof(*entry->busaddr),
DRM_MEM_PAGES );
if ( !entry->busaddr ) {
drm_free( entry->pagelist,
entry->pages * sizeof(*entry->pagelist),
DRM_MEM_PAGES );
drm_free( entry,
sizeof(*entry),
DRM_MEM_SGLISTS );
return -ENOMEM;
}
memset( (void *)entry->busaddr, 0, pages * sizeof(*entry->busaddr) );
entry->virtual = vmalloc_32( pages << PAGE_SHIFT );
if ( !entry->virtual ) {
drm_free( entry->busaddr,
entry->pages * sizeof(*entry->busaddr),
DRM_MEM_PAGES );
drm_free( entry->pagelist,
entry->pages * sizeof(*entry->pagelist),
DRM_MEM_PAGES );
drm_free( entry,
sizeof(*entry),
DRM_MEM_SGLISTS );
return -ENOMEM;
}
/* This also forces the mapping of COW pages, so our page list
* will be valid. Please don't remove it...
*/
memset( entry->virtual, 0, pages << PAGE_SHIFT );
entry->handle = ScatterHandle((unsigned long)entry->virtual);
DRM_DEBUG( "sg alloc handle = %08lx\n", entry->handle );
DRM_DEBUG( "sg alloc virtual = %p\n", entry->virtual );
for (i = (unsigned long)entry->virtual, j = 0; j < pages;
i += PAGE_SIZE, j++) {
entry->pagelist[j] = vmalloc_to_page((void *)i);
if (!entry->pagelist[j])
goto failed;
SetPageReserved(entry->pagelist[j]);
}
request.handle = entry->handle;
if ( copy_to_user( argp, &request, sizeof(request) ) ) {
drm_sg_cleanup( entry );
return -EFAULT;
}
dev->sg = entry;
#if DEBUG_SCATTER
/* Verify that each page points to its virtual address, and vice
* versa.
*/
{
int error = 0;
for ( i = 0 ; i < pages ; i++ ) {
unsigned long *tmp;
tmp = page_address( entry->pagelist[i] );
for ( j = 0 ;
j < PAGE_SIZE / sizeof(unsigned long) ;
j++, tmp++ ) {
*tmp = 0xcafebabe;
}
tmp = (unsigned long *)((u8 *)entry->virtual +
(PAGE_SIZE * i));
for( j = 0 ;
j < PAGE_SIZE / sizeof(unsigned long) ;
j++, tmp++ ) {
if ( *tmp != 0xcafebabe && error == 0 ) {
error = 1;
DRM_ERROR( "Scatter allocation error, "
"pagelist does not match "
"virtual mapping\n" );
}
}
tmp = page_address( entry->pagelist[i] );
for(j = 0 ;
j < PAGE_SIZE / sizeof(unsigned long) ;
j++, tmp++) {
*tmp = 0;
}
}
if (error == 0)
DRM_ERROR( "Scatter allocation matches pagelist\n" );
}
#endif
return 0;
failed:
drm_sg_cleanup( entry );
return -ENOMEM;
}
int drm_sg_free( struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg )
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->head->dev;
drm_scatter_gather_t request;
drm_sg_mem_t *entry;
if (!drm_core_check_feature(dev, DRIVER_SG))
return -EINVAL;
if ( copy_from_user( &request,
(drm_scatter_gather_t __user *)arg,
sizeof(request) ) )
return -EFAULT;
entry = dev->sg;
dev->sg = NULL;
if ( !entry || entry->handle != request.handle )
return -EINVAL;
DRM_DEBUG( "sg free virtual = %p\n", entry->virtual );
drm_sg_cleanup( entry );
return 0;
}