diff options
Diffstat (limited to 'linux-core/drm_scatter.c')
| -rw-r--r-- | linux-core/drm_scatter.c | 218 |
1 files changed, 218 insertions, 0 deletions
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; +} |