i915: add dma-buf vmap support for exporting vmapped buffer

This is used to export a vmapping to the udl driver so that
i915 and udl can share the udl scanout.

Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Dave Airlie 2012-05-22 13:09:21 +01:00
parent 946c7491b3
commit 9a70cc2a78
2 changed files with 58 additions and 0 deletions

View file

@ -942,6 +942,9 @@ struct drm_i915_gem_object {
/* prime dma-buf support */
struct sg_table *sg_table;
void *dma_buf_vmapping;
int vmapping_count;
/**
* Used for performing relocations during execbuffer insertion.
*/

View file

@ -74,6 +74,59 @@ static void i915_gem_dmabuf_release(struct dma_buf *dma_buf)
}
}
static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
{
struct drm_i915_gem_object *obj = dma_buf->priv;
struct drm_device *dev = obj->base.dev;
int ret;
ret = i915_mutex_lock_interruptible(dev);
if (ret)
return ERR_PTR(ret);
if (obj->dma_buf_vmapping) {
obj->vmapping_count++;
goto out_unlock;
}
if (!obj->pages) {
ret = i915_gem_object_get_pages_gtt(obj, __GFP_NORETRY | __GFP_NOWARN);
if (ret) {
mutex_unlock(&dev->struct_mutex);
return ERR_PTR(ret);
}
}
obj->dma_buf_vmapping = vmap(obj->pages, obj->base.size / PAGE_SIZE, 0, PAGE_KERNEL);
if (!obj->dma_buf_vmapping) {
DRM_ERROR("failed to vmap object\n");
goto out_unlock;
}
obj->vmapping_count = 1;
out_unlock:
mutex_unlock(&dev->struct_mutex);
return obj->dma_buf_vmapping;
}
static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
{
struct drm_i915_gem_object *obj = dma_buf->priv;
struct drm_device *dev = obj->base.dev;
int ret;
ret = i915_mutex_lock_interruptible(dev);
if (ret)
return;
--obj->vmapping_count;
if (obj->vmapping_count == 0) {
vunmap(obj->dma_buf_vmapping);
obj->dma_buf_vmapping = NULL;
}
mutex_unlock(&dev->struct_mutex);
}
static void *i915_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
{
return NULL;
@ -107,6 +160,8 @@ static const struct dma_buf_ops i915_dmabuf_ops = {
.kunmap = i915_gem_dmabuf_kunmap,
.kunmap_atomic = i915_gem_dmabuf_kunmap_atomic,
.mmap = i915_gem_dmabuf_mmap,
.vmap = i915_gem_dmabuf_vmap,
.vunmap = i915_gem_dmabuf_vunmap,
};
struct dma_buf *i915_gem_prime_export(struct drm_device *dev,