*
* Authors: Alex Deucher
*/
+
+/**
+ * DOC: PRIME Buffer Sharing
+ *
+ * The following callback implementations are used for :ref:`sharing GEM buffer
+ * objects between different devices via PRIME <prime_buffer_sharing>`.
+ */
+
#include <drm/drmP.h>
#include "amdgpu.h"
static const struct dma_buf_ops amdgpu_dmabuf_ops;
+/**
+ * amdgpu_gem_prime_get_sg_table - &drm_driver.gem_prime_get_sg_table
+ * implementation
+ * @obj: GEM buffer object
+ *
+ * Returns:
+ * A scatter/gather table for the pinned pages of the buffer object's memory.
+ */
struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object *obj)
{
struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages);
}
+/**
+ * amdgpu_gem_prime_vmap - &dma_buf_ops.vmap implementation
+ * @obj: GEM buffer object
+ *
+ * Sets up an in-kernel virtual mapping of the buffer object's memory.
+ *
+ * Returns:
+ * The virtual address of the mapping or an error pointer.
+ */
void *amdgpu_gem_prime_vmap(struct drm_gem_object *obj)
{
struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
return bo->dma_buf_vmap.virtual;
}
+/**
+ * amdgpu_gem_prime_vunmap - &dma_buf_ops.vunmap implementation
+ * @obj: GEM buffer object
+ * @vaddr: virtual address (unused)
+ *
+ * Tears down the in-kernel virtual mapping of the buffer object's memory.
+ */
void amdgpu_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
{
struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
ttm_bo_kunmap(&bo->dma_buf_vmap);
}
+/**
+ * amdgpu_gem_prime_mmap - &drm_driver.gem_prime_mmap implementation
+ * @obj: GEM buffer object
+ * @vma: virtual memory area
+ *
+ * Sets up a userspace mapping of the buffer object's memory in the given
+ * virtual memory area.
+ *
+ * Returns:
+ * 0 on success or negative error code.
+ */
int amdgpu_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
{
struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
return ret;
}
+/**
+ * amdgpu_gem_prime_import_sg_table - &drm_driver.gem_prime_import_sg_table
+ * implementation
+ * @dev: DRM device
+ * @attach: DMA-buf attachment
+ * @sg: Scatter/gather table
+ *
+ * Import shared DMA buffer memory exported by another device.
+ *
+ * Returns:
+ * A new GEM buffer object of the given DRM device, representing the memory
+ * described by the given DMA-buf attachment and scatter/gather table.
+ */
struct drm_gem_object *
amdgpu_gem_prime_import_sg_table(struct drm_device *dev,
struct dma_buf_attachment *attach,
return ERR_PTR(ret);
}
+/**
+ * amdgpu_gem_map_attach - &dma_buf_ops.attach implementation
+ * @dma_buf: shared DMA buffer
+ * @attach: DMA-buf attachment
+ *
+ * Makes sure that the shared DMA buffer can be accessed by the target device.
+ * For now, simply pins it to the GTT domain, where it should be accessible by
+ * all DMA devices.
+ *
+ * Returns:
+ * 0 on success or negative error code.
+ */
static int amdgpu_gem_map_attach(struct dma_buf *dma_buf,
- struct device *target_dev,
struct dma_buf_attachment *attach)
{
struct drm_gem_object *obj = dma_buf->priv;
struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
long r;
- r = drm_gem_map_attach(dma_buf, target_dev, attach);
+ r = drm_gem_map_attach(dma_buf, attach);
if (r)
return r;
}
/* pin buffer into GTT */
- r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT, NULL);
+ r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT);
if (r)
goto error_unreserve;
return r;
}
+/**
+ * amdgpu_gem_map_detach - &dma_buf_ops.detach implementation
+ * @dma_buf: shared DMA buffer
+ * @attach: DMA-buf attachment
+ *
+ * This is called when a shared DMA buffer no longer needs to be accessible by
+ * the other device. For now, simply unpins the buffer from GTT.
+ */
static void amdgpu_gem_map_detach(struct dma_buf *dma_buf,
struct dma_buf_attachment *attach)
{
drm_gem_map_detach(dma_buf, attach);
}
+/**
+ * amdgpu_gem_prime_res_obj - &drm_driver.gem_prime_res_obj implementation
+ * @obj: GEM buffer object
+ *
+ * Returns:
+ * The buffer object's reservation object.
+ */
struct reservation_object *amdgpu_gem_prime_res_obj(struct drm_gem_object *obj)
{
struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
return bo->tbo.resv;
}
+/**
+ * amdgpu_gem_begin_cpu_access - &dma_buf_ops.begin_cpu_access implementation
+ * @dma_buf: shared DMA buffer
+ * @direction: direction of DMA transfer
+ *
+ * This is called before CPU access to the shared DMA buffer's memory. If it's
+ * a read access, the buffer is moved to the GTT domain if possible, for optimal
+ * CPU read performance.
+ *
+ * Returns:
+ * 0 on success or negative error code.
+ */
static int amdgpu_gem_begin_cpu_access(struct dma_buf *dma_buf,
enum dma_data_direction direction)
{
return ret;
if (!bo->pin_count && (bo->allowed_domains & AMDGPU_GEM_DOMAIN_GTT)) {
- amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
+ amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
}
.release = drm_gem_dmabuf_release,
.begin_cpu_access = amdgpu_gem_begin_cpu_access,
.map = drm_gem_dmabuf_kmap,
- .map_atomic = drm_gem_dmabuf_kmap_atomic,
.unmap = drm_gem_dmabuf_kunmap,
- .unmap_atomic = drm_gem_dmabuf_kunmap_atomic,
.mmap = drm_gem_dmabuf_mmap,
.vmap = drm_gem_dmabuf_vmap,
.vunmap = drm_gem_dmabuf_vunmap,
};
+/**
+ * amdgpu_gem_prime_export - &drm_driver.gem_prime_export implementation
+ * @dev: DRM device
+ * @gobj: GEM buffer object
+ * @flags: flags like DRM_CLOEXEC and DRM_RDWR
+ *
+ * The main work is done by the &drm_gem_prime_export helper, which in turn
+ * uses &amdgpu_gem_prime_res_obj.
+ *
+ * Returns:
+ * Shared DMA buffer representing the GEM buffer object from the given device.
+ */
struct dma_buf *amdgpu_gem_prime_export(struct drm_device *dev,
struct drm_gem_object *gobj,
int flags)
return buf;
}
+/**
+ * amdgpu_gem_prime_import - &drm_driver.gem_prime_import implementation
+ * @dev: DRM device
+ * @dma_buf: Shared DMA buffer
+ *
+ * The main work is done by the &drm_gem_prime_import helper, which in turn
+ * uses &amdgpu_gem_prime_import_sg_table.
+ *
+ * Returns:
+ * GEM buffer object representing the shared DMA buffer for the given device.
+ */
struct drm_gem_object *amdgpu_gem_prime_import(struct drm_device *dev,
struct dma_buf *dma_buf)
{
projects / linux.git / blobdiff