1 files changed, 231 insertions, 0 deletions

diff --git a/drivers/char/drm/drm_scatter.c b/drivers/char/drm/drm_scatter.c
new file mode 100644
index 000000000000..54fddb6ea2d1
--- /dev/null
+++ b/drivers/char/drm/drm_scatter.c
@@ -0,0 +1,231 @@
+/**
+ * \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 );
+}
+
+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 = (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++ ) {
+                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;
+}