linux/drivers/gpu/drm/sis/sis_drv.c
Dave Airlie 466e69b8b0 drm: move pci bus master enable into driver.
The current enabling of bus mastering in the drm midlayer allows a large
race condition under kexec. When a kexec'ed kernel re-enables bus mastering
for the GPU, previously setup dma blocks may cause writes to random pieces
of memory. On radeon the writeback mechanism can cause these sorts of issues.

This patch doesn't fix the problem, but it moves the bus master enable under
the individual drivers control so they can move enabling it until later in
their load cycle and close the race.

Fix for radeon kms driver will be in a follow-up patch.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-02-16 18:31:07 +00:00

145 lines
3.7 KiB
C

/* sis.c -- sis driver -*- linux-c -*-
*
* Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
* 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/module.h>
#include "drmP.h"
#include "sis_drm.h"
#include "sis_drv.h"
#include "drm_pciids.h"
static struct pci_device_id pciidlist[] = {
sisdrv_PCI_IDS
};
static int sis_driver_load(struct drm_device *dev, unsigned long chipset)
{
drm_sis_private_t *dev_priv;
pci_set_master(dev->pdev);
dev_priv = kzalloc(sizeof(drm_sis_private_t), GFP_KERNEL);
if (dev_priv == NULL)
return -ENOMEM;
dev->dev_private = (void *)dev_priv;
dev_priv->chipset = chipset;
idr_init(&dev->object_name_idr);
return 0;
}
static int sis_driver_unload(struct drm_device *dev)
{
drm_sis_private_t *dev_priv = dev->dev_private;
idr_remove_all(&dev_priv->object_idr);
idr_destroy(&dev_priv->object_idr);
kfree(dev_priv);
return 0;
}
static const struct file_operations sis_driver_fops = {
.owner = THIS_MODULE,
.open = drm_open,
.release = drm_release,
.unlocked_ioctl = drm_ioctl,
.mmap = drm_mmap,
.poll = drm_poll,
.fasync = drm_fasync,
.llseek = noop_llseek,
};
static int sis_driver_open(struct drm_device *dev, struct drm_file *file)
{
struct sis_file_private *file_priv;
DRM_DEBUG_DRIVER("\n");
file_priv = kmalloc(sizeof(*file_priv), GFP_KERNEL);
if (!file_priv)
return -ENOMEM;
file->driver_priv = file_priv;
INIT_LIST_HEAD(&file_priv->obj_list);
return 0;
}
void sis_driver_postclose(struct drm_device *dev, struct drm_file *file)
{
struct sis_file_private *file_priv = file->driver_priv;
kfree(file_priv);
}
static struct drm_driver driver = {
.driver_features = DRIVER_USE_AGP | DRIVER_USE_MTRR,
.load = sis_driver_load,
.unload = sis_driver_unload,
.open = sis_driver_open,
.postclose = sis_driver_postclose,
.dma_quiescent = sis_idle,
.reclaim_buffers = NULL,
.reclaim_buffers_idlelocked = sis_reclaim_buffers_locked,
.lastclose = sis_lastclose,
.ioctls = sis_ioctls,
.fops = &sis_driver_fops,
.name = DRIVER_NAME,
.desc = DRIVER_DESC,
.date = DRIVER_DATE,
.major = DRIVER_MAJOR,
.minor = DRIVER_MINOR,
.patchlevel = DRIVER_PATCHLEVEL,
};
static struct pci_driver sis_pci_driver = {
.name = DRIVER_NAME,
.id_table = pciidlist,
};
static int __init sis_init(void)
{
driver.num_ioctls = sis_max_ioctl;
return drm_pci_init(&driver, &sis_pci_driver);
}
static void __exit sis_exit(void)
{
drm_pci_exit(&driver, &sis_pci_driver);
}
module_init(sis_init);
module_exit(sis_exit);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL and additional rights");