freebsd-nq/sys/dev/drm/drm_vm.c
Robert Noland a80ca4341a vm_offset_t is unsigned, so compare of >= 0 is not needed.
Found with:	Coverity Prevent(tm)
CID:		2259

MFC after:	3 days
2009-03-20 18:35:16 +00:00

129 lines
3.6 KiB
C

/*-
* Copyright 2003 Eric Anholt
* 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
* ERIC ANHOLT 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/** @file drm_vm.c
* Support code for mmaping of DRM maps.
*/
#include "dev/drm/drmP.h"
#include "dev/drm/drm.h"
int drm_mmap(struct cdev *kdev, vm_offset_t offset, vm_paddr_t *paddr,
int prot)
{
struct drm_device *dev = drm_get_device_from_kdev(kdev);
struct drm_file *file_priv = NULL;
drm_local_map_t *map;
enum drm_map_type type;
vm_paddr_t phys;
int error;
/* d_mmap gets called twice, we can only reference file_priv during
* the first call. We need to assume that if error is EBADF the
* call was succesful and the client is authenticated.
*/
error = devfs_get_cdevpriv((void **)&file_priv);
if (error == ENOENT) {
DRM_ERROR("Could not find authenticator!\n");
return EINVAL;
}
if (file_priv && !file_priv->authenticated)
return EACCES;
if (dev->dma && offset < ptoa(dev->dma->page_count)) {
drm_device_dma_t *dma = dev->dma;
DRM_SPINLOCK(&dev->dma_lock);
if (dma->pagelist != NULL) {
unsigned long page = offset >> PAGE_SHIFT;
unsigned long phys = dma->pagelist[page];
DRM_SPINUNLOCK(&dev->dma_lock);
*paddr = phys;
return 0;
} else {
DRM_SPINUNLOCK(&dev->dma_lock);
return -1;
}
}
/* A sequential search of a linked list is
fine here because: 1) there will only be
about 5-10 entries in the list and, 2) a
DRI client only has to do this mapping
once, so it doesn't have to be optimized
for performance, even if the list was a
bit longer. */
DRM_LOCK();
TAILQ_FOREACH(map, &dev->maplist, link) {
if (offset >= map->offset && offset < map->offset + map->size)
break;
}
if (map == NULL) {
DRM_DEBUG("Can't find map, requested offset = %016lx\n",
(unsigned long)offset);
TAILQ_FOREACH(map, &dev->maplist, link) {
DRM_DEBUG("map offset = %016lx, handle = %016lx\n",
(unsigned long)map->offset,
(unsigned long)map->handle);
}
DRM_UNLOCK();
return -1;
}
if (((map->flags&_DRM_RESTRICTED) && !DRM_SUSER(DRM_CURPROC))) {
DRM_UNLOCK();
DRM_DEBUG("restricted map\n");
return -1;
}
type = map->type;
DRM_UNLOCK();
switch (type) {
case _DRM_FRAME_BUFFER:
case _DRM_REGISTERS:
case _DRM_AGP:
phys = offset;
break;
case _DRM_CONSISTENT:
phys = vtophys((char *)map->handle + (offset - map->offset));
break;
case _DRM_SCATTER_GATHER:
case _DRM_SHM:
phys = vtophys(offset);
break;
default:
DRM_ERROR("bad map type %d\n", type);
return -1; /* This should never happen. */
}
*paddr = phys;
return 0;
}