f7c72773de
Move code for managing DMA max segment size parameter to separate functions. This patch also replaces devm_kzalloc() with kzalloc() and adds proper kfree call. devm_kzalloc() cannot be used for dma_params structure, because it will be freed on driver remove not on device release. This means in case of Exynos DRM being compiled as module and loaded 2 times, a user-after-free issue will happen. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Inki Dae <inki.dae@samsung.com>
139 lines
3.1 KiB
C
139 lines
3.1 KiB
C
/* exynos_drm_iommu.c
|
|
*
|
|
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
|
|
* Author: Inki Dae <inki.dae@samsung.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License as published by the
|
|
* Free Software Foundation; either version 2 of the License, or (at your
|
|
* option) any later version.
|
|
*/
|
|
|
|
#include <drm/drmP.h>
|
|
#include <drm/exynos_drm.h>
|
|
|
|
#include <linux/dma-mapping.h>
|
|
#include <linux/iommu.h>
|
|
#include <linux/kref.h>
|
|
|
|
#include <asm/dma-iommu.h>
|
|
|
|
#include "exynos_drm_drv.h"
|
|
#include "exynos_drm_iommu.h"
|
|
|
|
static inline int configure_dma_max_seg_size(struct device *dev)
|
|
{
|
|
if (!dev->dma_parms)
|
|
dev->dma_parms = kzalloc(sizeof(*dev->dma_parms), GFP_KERNEL);
|
|
if (!dev->dma_parms)
|
|
return -ENOMEM;
|
|
|
|
dma_set_max_seg_size(dev, DMA_BIT_MASK(32));
|
|
return 0;
|
|
}
|
|
|
|
static inline void clear_dma_max_seg_size(struct device *dev)
|
|
{
|
|
kfree(dev->dma_parms);
|
|
dev->dma_parms = NULL;
|
|
}
|
|
|
|
/*
|
|
* drm_create_iommu_mapping - create a mapping structure
|
|
*
|
|
* @drm_dev: DRM device
|
|
*/
|
|
int drm_create_iommu_mapping(struct drm_device *drm_dev)
|
|
{
|
|
struct dma_iommu_mapping *mapping = NULL;
|
|
struct exynos_drm_private *priv = drm_dev->dev_private;
|
|
|
|
if (!priv->da_start)
|
|
priv->da_start = EXYNOS_DEV_ADDR_START;
|
|
if (!priv->da_space_size)
|
|
priv->da_space_size = EXYNOS_DEV_ADDR_SIZE;
|
|
|
|
mapping = arm_iommu_create_mapping(&platform_bus_type, priv->da_start,
|
|
priv->da_space_size);
|
|
|
|
if (IS_ERR(mapping))
|
|
return PTR_ERR(mapping);
|
|
|
|
priv->mapping = mapping;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* drm_release_iommu_mapping - release iommu mapping structure
|
|
*
|
|
* @drm_dev: DRM device
|
|
*
|
|
* if mapping->kref becomes 0 then all things related to iommu mapping
|
|
* will be released
|
|
*/
|
|
void drm_release_iommu_mapping(struct drm_device *drm_dev)
|
|
{
|
|
struct exynos_drm_private *priv = drm_dev->dev_private;
|
|
|
|
arm_iommu_release_mapping(priv->mapping);
|
|
}
|
|
|
|
/*
|
|
* drm_iommu_attach_device- attach device to iommu mapping
|
|
*
|
|
* @drm_dev: DRM device
|
|
* @subdrv_dev: device to be attach
|
|
*
|
|
* This function should be called by sub drivers to attach it to iommu
|
|
* mapping.
|
|
*/
|
|
int drm_iommu_attach_device(struct drm_device *drm_dev,
|
|
struct device *subdrv_dev)
|
|
{
|
|
struct exynos_drm_private *priv = drm_dev->dev_private;
|
|
int ret;
|
|
|
|
if (!priv->mapping)
|
|
return 0;
|
|
|
|
|
|
ret = configure_dma_max_seg_size(subdrv_dev);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (subdrv_dev->archdata.mapping)
|
|
arm_iommu_detach_device(subdrv_dev);
|
|
|
|
ret = arm_iommu_attach_device(subdrv_dev, priv->mapping);
|
|
if (ret < 0) {
|
|
DRM_DEBUG_KMS("failed iommu attach.\n");
|
|
clear_dma_max_seg_size(subdrv_dev);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* drm_iommu_detach_device -detach device address space mapping from device
|
|
*
|
|
* @drm_dev: DRM device
|
|
* @subdrv_dev: device to be detached
|
|
*
|
|
* This function should be called by sub drivers to detach it from iommu
|
|
* mapping
|
|
*/
|
|
void drm_iommu_detach_device(struct drm_device *drm_dev,
|
|
struct device *subdrv_dev)
|
|
{
|
|
struct exynos_drm_private *priv = drm_dev->dev_private;
|
|
struct dma_iommu_mapping *mapping = priv->mapping;
|
|
|
|
if (!mapping || !mapping->domain)
|
|
return;
|
|
|
|
arm_iommu_detach_device(subdrv_dev);
|
|
clear_dma_max_seg_size(subdrv_dev);
|
|
}
|