ddx driver cleanup.

5 files changed, 716 insertions, 0 deletions

diff --git a/linux-core/ati_pcigart.c b/linux-core/ati_pcigart.c
new file mode 100644
index 00000000..93c5148f
--- /dev/null
+++ b/linux-core/ati_pcigart.c
@@ -0,0 +1,138 @@
+/* ati_pcigart.h -- ATI PCI GART support -*- linux-c -*-
+ * Created: Wed Dec 13 21:52:19 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.
+ *
+ * Authors:
+ *   Gareth Hughes <gareth@valinux.com>
+ */
+
+#define __NO_VERSION__
+#include "drmP.h"
+
+#if PAGE_SIZE == 8192
+# define ATI_PCIGART_TABLE_ORDER 	2
+# define ATI_PCIGART_TABLE_PAGES 	(1 << 2)
+#elif PAGE_SIZE == 4096
+# define ATI_PCIGART_TABLE_ORDER 	3
+# define ATI_PCIGART_TABLE_PAGES 	(1 << 3)
+#elif
+# error - PAGE_SIZE not 8K or 4K
+#endif
+
+# define ATI_MAX_PCIGART_PAGES		8192	/* 32 MB aperture, 4K pages */
+# define ATI_PCIGART_PAGE_SIZE		4096	/* PCI GART page size */
+
+static unsigned long DRM(ati_alloc_pcigart_table)( void )
+{
+	unsigned long address;
+	struct page *page;
+	int i;
+	DRM_DEBUG( "%s\n", __FUNCTION__ );
+
+	address = __get_free_pages( GFP_KERNEL, ATI_PCIGART_TABLE_ORDER );
+	if ( address == 0UL ) {
+		return 0;
+	}
+
+	page = virt_to_page( address );
+
+	for ( i = 0 ; i <= ATI_PCIGART_TABLE_PAGES ; i++, page++ ) {
+		atomic_inc( &page->count );
+		SetPageReserved( page );
+	}
+
+	DRM_DEBUG( "%s: returning 0x%08lx\n", __FUNCTION__, address );
+	return address;
+}
+
+static void DRM(ati_free_pcigart_table)( unsigned long address )
+{
+	struct page *page;
+	int i;
+	DRM_DEBUG( "%s\n", __FUNCTION__ );
+
+	if ( !address ) return;
+
+	page = virt_to_page( address );
+
+	for ( i = 0 ; i <= ATI_PCIGART_TABLE_PAGES ; i++, page++ ) {
+		atomic_dec( &page->count );
+		ClearPageReserved( page );
+	}
+
+	free_pages( address, ATI_PCIGART_TABLE_ORDER );
+}
+
+unsigned long DRM(ati_pcigart_init)( drm_device_t *dev )
+{
+	drm_sg_mem_t *entry = dev->sg;
+	unsigned long address;
+	unsigned long pages;
+	u32 *pci_gart, page_base;
+	int i, j;
+
+	if ( !entry ) {
+		DRM_ERROR( "no scatter/gather memory!\n" );
+		return 0;
+	}
+
+	address = DRM(ati_alloc_pcigart_table)();
+	if ( !address ) {
+		DRM_ERROR( "cannot allocate PCI GART page!\n" );
+		return 0;
+	}
+
+	pci_gart = (u32 *)address;
+
+	pages = ( entry->pages <= ATI_MAX_PCIGART_PAGES )
+		? entry->pages : ATI_MAX_PCIGART_PAGES;
+
+	memset( pci_gart, 0, ATI_MAX_PCIGART_PAGES * sizeof(u32) );
+
+	for ( i = 0 ; i < pages ; i++ ) {
+		page_base = virt_to_bus( entry->pagelist[i]->virtual );
+		for (j = 0; j < (PAGE_SIZE / ATI_PCIGART_PAGE_SIZE); j++) {
+			*pci_gart++ = cpu_to_le32( page_base );
+			page_base += ATI_PCIGART_PAGE_SIZE;
+		}
+	}
+
+#if __i386__
+	asm volatile ( "wbinvd" ::: "memory" );
+#else
+	mb();
+#endif
+
+	return address;
+}
+
+int DRM(ati_pcigart_cleanup)( unsigned long address )
+{
+
+	if ( address ) {
+		DRM(ati_free_pcigart_table)( address );
+	}
+
+	return 0;
+}
diff --git a/linux-core/drm_scatter.c b/linux-core/drm_scatter.c
new file mode 100644
index 00000000..a0371074
--- /dev/null
+++ b/linux-core/drm_scatter.c
@@ -0,0 +1,218 @@
+/* drm_scatter.h -- IOCTLs to manage scatter/gather memory -*- linux-c -*-
+ * 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.
+ *
+ * Authors:
+ *   Gareth Hughes <gareth@valinux.com>
+ */
+
+#define __NO_VERSION__
+#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->pagelist,
+		  entry->pages * sizeof(*entry->pagelist),
+		  DRM_MEM_PAGES );
+	DRM(free)( entry,
+		  sizeof(*entry),
+		  DRM_MEM_SGLISTS );
+}
+
+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->dev;
+	drm_scatter_gather_t request;
+	drm_sg_mem_t *entry;
+	unsigned long pages, i, j;
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *pte;
+
+	DRM_DEBUG( "%s\n", __FUNCTION__ );
+
+	if ( dev->sg )
+		return -EINVAL;
+
+	if ( copy_from_user( &request,
+			     (drm_scatter_gather_t *)arg,
+			     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;
+	}
+
+	entry->virtual = vmalloc_32( pages << PAGE_SHIFT );
+	if ( !entry->virtual ) {
+		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 = (unsigned long)entry->virtual;
+
+	DRM_DEBUG( "sg alloc handle  = %08lx\n", entry->handle );
+	DRM_DEBUG( "sg alloc virtual = %p\n", entry->virtual );
+
+	for ( i = entry->handle, j = 0 ; j < pages ; i += PAGE_SIZE, j++ ) {
+		pgd = pgd_offset_k( i );
+		if ( !pgd_present( *pgd ) )
+			goto failed;
+
+		pmd = pmd_offset( pgd, i );
+		if ( !pmd_present( *pmd ) )
+			goto failed;
+
+		pte = pte_offset( pmd, i );
+		if ( !pte_present( *pte ) )
+			goto failed;
+
+		entry->pagelist[j] = pte_page( *pte );
+
+		SetPageReserved( entry->pagelist[j] );
+	}
+
+	request.handle = entry->handle;
+
+	if ( copy_to_user( (drm_scatter_gather_t *)arg,
+			   &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 = (unsigned long *)entry->pagelist[i]->virtual;
+		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 = (unsigned long *)entry->pagelist[i]->virtual;
+		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->dev;
+	drm_scatter_gather_t request;
+	drm_sg_mem_t *entry;
+
+	if ( copy_from_user( &request,
+			     (drm_scatter_gather_t *)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;
+}
diff --git a/linux/ati_pcigart.h b/linux/ati_pcigart.h
new file mode 100644
index 00000000..93c5148f
--- /dev/null
+++ b/linux/ati_pcigart.h
@@ -0,0 +1,138 @@
+/* ati_pcigart.h -- ATI PCI GART support -*- linux-c -*-
+ * Created: Wed Dec 13 21:52:19 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.
+ *
+ * Authors:
+ *   Gareth Hughes <gareth@valinux.com>
+ */
+
+#define __NO_VERSION__
+#include "drmP.h"
+
+#if PAGE_SIZE == 8192
+# define ATI_PCIGART_TABLE_ORDER 	2
+# define ATI_PCIGART_TABLE_PAGES 	(1 << 2)
+#elif PAGE_SIZE == 4096
+# define ATI_PCIGART_TABLE_ORDER 	3
+# define ATI_PCIGART_TABLE_PAGES 	(1 << 3)
+#elif
+# error - PAGE_SIZE not 8K or 4K
+#endif
+
+# define ATI_MAX_PCIGART_PAGES		8192	/* 32 MB aperture, 4K pages */
+# define ATI_PCIGART_PAGE_SIZE		4096	/* PCI GART page size */
+
+static unsigned long DRM(ati_alloc_pcigart_table)( void )
+{
+	unsigned long address;
+	struct page *page;
+	int i;
+	DRM_DEBUG( "%s\n", __FUNCTION__ );
+
+	address = __get_free_pages( GFP_KERNEL, ATI_PCIGART_TABLE_ORDER );
+	if ( address == 0UL ) {
+		return 0;
+	}
+
+	page = virt_to_page( address );
+
+	for ( i = 0 ; i <= ATI_PCIGART_TABLE_PAGES ; i++, page++ ) {
+		atomic_inc( &page->count );
+		SetPageReserved( page );
+	}
+
+	DRM_DEBUG( "%s: returning 0x%08lx\n", __FUNCTION__, address );
+	return address;
+}
+
+static void DRM(ati_free_pcigart_table)( unsigned long address )
+{
+	struct page *page;
+	int i;
+	DRM_DEBUG( "%s\n", __FUNCTION__ );
+
+	if ( !address ) return;
+
+	page = virt_to_page( address );
+
+	for ( i = 0 ; i <= ATI_PCIGART_TABLE_PAGES ; i++, page++ ) {
+		atomic_dec( &page->count );
+		ClearPageReserved( page );
+	}
+
+	free_pages( address, ATI_PCIGART_TABLE_ORDER );
+}
+
+unsigned long DRM(ati_pcigart_init)( drm_device_t *dev )
+{
+	drm_sg_mem_t *entry = dev->sg;
+	unsigned long address;
+	unsigned long pages;
+	u32 *pci_gart, page_base;
+	int i, j;
+
+	if ( !entry ) {
+		DRM_ERROR( "no scatter/gather memory!\n" );
+		return 0;
+	}
+
+	address = DRM(ati_alloc_pcigart_table)();
+	if ( !address ) {
+		DRM_ERROR( "cannot allocate PCI GART page!\n" );
+		return 0;
+	}
+
+	pci_gart = (u32 *)address;
+
+	pages = ( entry->pages <= ATI_MAX_PCIGART_PAGES )
+		? entry->pages : ATI_MAX_PCIGART_PAGES;
+
+	memset( pci_gart, 0, ATI_MAX_PCIGART_PAGES * sizeof(u32) );
+
+	for ( i = 0 ; i < pages ; i++ ) {
+		page_base = virt_to_bus( entry->pagelist[i]->virtual );
+		for (j = 0; j < (PAGE_SIZE / ATI_PCIGART_PAGE_SIZE); j++) {
+			*pci_gart++ = cpu_to_le32( page_base );
+			page_base += ATI_PCIGART_PAGE_SIZE;
+		}
+	}
+
+#if __i386__
+	asm volatile ( "wbinvd" ::: "memory" );
+#else
+	mb();
+#endif
+
+	return address;
+}
+
+int DRM(ati_pcigart_cleanup)( unsigned long address )
+{
+
+	if ( address ) {
+		DRM(ati_free_pcigart_table)( address );
+	}
+
+	return 0;
+}
diff --git a/linux/drm_scatter.h b/linux/drm_scatter.h
new file mode 100644
index 00000000..a0371074
--- /dev/null
+++ b/linux/drm_scatter.h
@@ -0,0 +1,218 @@
+/* drm_scatter.h -- IOCTLs to manage scatter/gather memory -*- linux-c -*-
+ * 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.
+ *
+ * Authors:
+ *   Gareth Hughes <gareth@valinux.com>
+ */
+
+#define __NO_VERSION__
+#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->pagelist,
+		  entry->pages * sizeof(*entry->pagelist),
+		  DRM_MEM_PAGES );
+	DRM(free)( entry,
+		  sizeof(*entry),
+		  DRM_MEM_SGLISTS );
+}
+
+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->dev;
+	drm_scatter_gather_t request;
+	drm_sg_mem_t *entry;
+	unsigned long pages, i, j;
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *pte;
+
+	DRM_DEBUG( "%s\n", __FUNCTION__ );
+
+	if ( dev->sg )
+		return -EINVAL;
+
+	if ( copy_from_user( &request,
+			     (drm_scatter_gather_t *)arg,
+			     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;
+	}
+
+	entry->virtual = vmalloc_32( pages << PAGE_SHIFT );
+	if ( !entry->virtual ) {
+		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 = (unsigned long)entry->virtual;
+
+	DRM_DEBUG( "sg alloc handle  = %08lx\n", entry->handle );
+	DRM_DEBUG( "sg alloc virtual = %p\n", entry->virtual );
+
+	for ( i = entry->handle, j = 0 ; j < pages ; i += PAGE_SIZE, j++ ) {
+		pgd = pgd_offset_k( i );
+		if ( !pgd_present( *pgd ) )
+			goto failed;
+
+		pmd = pmd_offset( pgd, i );
+		if ( !pmd_present( *pmd ) )
+			goto failed;
+
+		pte = pte_offset( pmd, i );
+		if ( !pte_present( *pte ) )
+			goto failed;
+
+		entry->pagelist[j] = pte_page( *pte );
+
+		SetPageReserved( entry->pagelist[j] );
+	}
+
+	request.handle = entry->handle;
+
+	if ( copy_to_user( (drm_scatter_gather_t *)arg,
+			   &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 = (unsigned long *)entry->pagelist[i]->virtual;
+		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 = (unsigned long *)entry->pagelist[i]->virtual;
+		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->dev;
+	drm_scatter_gather_t request;
+	drm_sg_mem_t *entry;
+
+	if ( copy_from_user( &request,
+			     (drm_scatter_gather_t *)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;
+}
diff --git a/linux/gamma_drm.h b/linux/gamma_drm.h
index 4a14f1ff..4c0f3729 100644
--- a/linux/gamma_drm.h
+++ b/linux/gamma_drm.h
@@ -1,3 +1,6 @@
+#ifndef _GAMMA_DRM_H_
+#define _GAMMA_DRM_H_
+
 typedef struct _drm_gamma_tex_region {
 	unsigned char next, prev; /* indices to form a circular LRU  */
 	unsigned char in_use;	/* owned by a client, or free? */
@@ -73,3 +76,4 @@ typedef struct drm_gamma_init {
 	unsigned int buffers_offset;
 } drm_gamma_init_t;
 
+#endif _GAMMA_DRM_H_