patch-2.4.8 linux/drivers/char/drm/drm_scatter.h

• Lines: 220
• Date: Fri Aug 10 18:14:42 2001
• Orig file: v2.4.7/linux/drivers/char/drm/drm_scatter.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.7/linux/drivers/char/drm/drm_scatter.h linux/drivers/char/drm/drm_scatter.h
@@ -0,0 +1,219 @@
+/* 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;
+	}
+	memset(entry->pagelist, 0, pages * sizeof(*entry->pagelist));
+
+	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;
+}