linux-stable/drivers/gpu/drm/virtio/virtgpu_object.c
Thomas Zimmermann 0cf2ef46c6 drm/shmem-helper: Use cached mappings by default
SHMEM-buffer backing storage is allocated from system memory; which is
typically cachable. The default mode for SHMEM objects is writecombine
though.

Unify SHMEM semantics by defaulting to cached mappings. The exception
is pages imported via dma-buf. DMA memory is usually not cached.

DRM drivers that require write-combined mappings set the map_wc flag
in struct drm_gem_shmem_object to true. This currently affects lima,
panfrost and v3d.

The drivers mgag200, udl, virtio and vkms continue to use default
shmem mappings.

The drivers cirrus and gm12u320 change caching flags. Both used
writecombine and now switch over to shmem defaults. Both drivers use
SHMEM objects as shadow buffers for internal video memory, so cached
mappings will not affect them negatively.

v3:
	* set value of shmem pointer before dereferencing it in
	  __drm_gem_shmem_create() (Dan, kernel test robot)
v2:
	* recreate patch on top of latest SHMEM helpers
	* update lima, panfrost, v3d to select writecombine (Daniel, Rob)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201117133156.26822-2-tzimmermann@suse.de
2020-11-24 09:10:21 +01:00

278 lines
7.8 KiB
C

/*
* Copyright (C) 2015 Red Hat, Inc.
* 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 THE COPYRIGHT OWNER(S) 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/dma-mapping.h>
#include <linux/moduleparam.h>
#include "virtgpu_drv.h"
static int virtio_gpu_virglrenderer_workaround = 1;
module_param_named(virglhack, virtio_gpu_virglrenderer_workaround, int, 0400);
int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev, uint32_t *resid)
{
if (virtio_gpu_virglrenderer_workaround) {
/*
* Hack to avoid re-using resource IDs.
*
* virglrenderer versions up to (and including) 0.7.0
* can't deal with that. virglrenderer commit
* "f91a9dd35715 Fix unlinking resources from hash
* table." (Feb 2019) fixes the bug.
*/
static atomic_t seqno = ATOMIC_INIT(0);
int handle = atomic_inc_return(&seqno);
*resid = handle + 1;
} else {
int handle = ida_alloc(&vgdev->resource_ida, GFP_KERNEL);
if (handle < 0)
return handle;
*resid = handle + 1;
}
return 0;
}
static void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t id)
{
if (!virtio_gpu_virglrenderer_workaround) {
ida_free(&vgdev->resource_ida, id - 1);
}
}
void virtio_gpu_cleanup_object(struct virtio_gpu_object *bo)
{
struct virtio_gpu_device *vgdev = bo->base.base.dev->dev_private;
virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
if (virtio_gpu_is_shmem(bo)) {
struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
if (shmem->pages) {
if (shmem->mapped) {
dma_unmap_sgtable(vgdev->vdev->dev.parent,
shmem->pages, DMA_TO_DEVICE, 0);
shmem->mapped = 0;
}
sg_free_table(shmem->pages);
kfree(shmem->pages);
shmem->pages = NULL;
drm_gem_shmem_unpin(&bo->base.base);
}
drm_gem_shmem_free_object(&bo->base.base);
} else if (virtio_gpu_is_vram(bo)) {
struct virtio_gpu_object_vram *vram = to_virtio_gpu_vram(bo);
spin_lock(&vgdev->host_visible_lock);
if (drm_mm_node_allocated(&vram->vram_node))
drm_mm_remove_node(&vram->vram_node);
spin_unlock(&vgdev->host_visible_lock);
drm_gem_free_mmap_offset(&vram->base.base.base);
drm_gem_object_release(&vram->base.base.base);
kfree(vram);
}
}
static void virtio_gpu_free_object(struct drm_gem_object *obj)
{
struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
struct virtio_gpu_device *vgdev = bo->base.base.dev->dev_private;
if (bo->created) {
virtio_gpu_cmd_unref_resource(vgdev, bo);
virtio_gpu_notify(vgdev);
/* completion handler calls virtio_gpu_cleanup_object() */
return;
}
virtio_gpu_cleanup_object(bo);
}
static const struct drm_gem_object_funcs virtio_gpu_shmem_funcs = {
.free = virtio_gpu_free_object,
.open = virtio_gpu_gem_object_open,
.close = virtio_gpu_gem_object_close,
.print_info = drm_gem_shmem_print_info,
.export = virtgpu_gem_prime_export,
.pin = drm_gem_shmem_pin,
.unpin = drm_gem_shmem_unpin,
.get_sg_table = drm_gem_shmem_get_sg_table,
.vmap = drm_gem_shmem_vmap,
.vunmap = drm_gem_shmem_vunmap,
.mmap = drm_gem_shmem_mmap,
};
bool virtio_gpu_is_shmem(struct virtio_gpu_object *bo)
{
return bo->base.base.funcs == &virtio_gpu_shmem_funcs;
}
struct drm_gem_object *virtio_gpu_create_object(struct drm_device *dev,
size_t size)
{
struct virtio_gpu_object_shmem *shmem;
struct drm_gem_shmem_object *dshmem;
shmem = kzalloc(sizeof(*shmem), GFP_KERNEL);
if (!shmem)
return NULL;
dshmem = &shmem->base.base;
dshmem->base.funcs = &virtio_gpu_shmem_funcs;
return &dshmem->base;
}
static int virtio_gpu_object_shmem_init(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object *bo,
struct virtio_gpu_mem_entry **ents,
unsigned int *nents)
{
bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
struct scatterlist *sg;
int si, ret;
ret = drm_gem_shmem_pin(&bo->base.base);
if (ret < 0)
return -EINVAL;
/*
* virtio_gpu uses drm_gem_shmem_get_sg_table instead of
* drm_gem_shmem_get_pages_sgt because virtio has it's own set of
* dma-ops. This is discouraged for other drivers, but should be fine
* since virtio_gpu doesn't support dma-buf import from other devices.
*/
shmem->pages = drm_gem_shmem_get_sg_table(&bo->base.base);
if (!shmem->pages) {
drm_gem_shmem_unpin(&bo->base.base);
return -EINVAL;
}
if (use_dma_api) {
ret = dma_map_sgtable(vgdev->vdev->dev.parent,
shmem->pages, DMA_TO_DEVICE, 0);
if (ret)
return ret;
*nents = shmem->mapped = shmem->pages->nents;
} else {
*nents = shmem->pages->orig_nents;
}
*ents = kvmalloc_array(*nents,
sizeof(struct virtio_gpu_mem_entry),
GFP_KERNEL);
if (!(*ents)) {
DRM_ERROR("failed to allocate ent list\n");
return -ENOMEM;
}
if (use_dma_api) {
for_each_sgtable_dma_sg(shmem->pages, sg, si) {
(*ents)[si].addr = cpu_to_le64(sg_dma_address(sg));
(*ents)[si].length = cpu_to_le32(sg_dma_len(sg));
(*ents)[si].padding = 0;
}
} else {
for_each_sgtable_sg(shmem->pages, sg, si) {
(*ents)[si].addr = cpu_to_le64(sg_phys(sg));
(*ents)[si].length = cpu_to_le32(sg->length);
(*ents)[si].padding = 0;
}
}
return 0;
}
int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object_params *params,
struct virtio_gpu_object **bo_ptr,
struct virtio_gpu_fence *fence)
{
struct virtio_gpu_object_array *objs = NULL;
struct drm_gem_shmem_object *shmem_obj;
struct virtio_gpu_object *bo;
struct virtio_gpu_mem_entry *ents;
unsigned int nents;
int ret;
*bo_ptr = NULL;
params->size = roundup(params->size, PAGE_SIZE);
shmem_obj = drm_gem_shmem_create(vgdev->ddev, params->size);
if (IS_ERR(shmem_obj))
return PTR_ERR(shmem_obj);
bo = gem_to_virtio_gpu_obj(&shmem_obj->base);
ret = virtio_gpu_resource_id_get(vgdev, &bo->hw_res_handle);
if (ret < 0)
goto err_free_gem;
bo->dumb = params->dumb;
if (fence) {
ret = -ENOMEM;
objs = virtio_gpu_array_alloc(1);
if (!objs)
goto err_put_id;
virtio_gpu_array_add_obj(objs, &bo->base.base);
ret = virtio_gpu_array_lock_resv(objs);
if (ret != 0)
goto err_put_objs;
}
ret = virtio_gpu_object_shmem_init(vgdev, bo, &ents, &nents);
if (ret != 0) {
virtio_gpu_free_object(&shmem_obj->base);
return ret;
}
if (params->blob) {
virtio_gpu_cmd_resource_create_blob(vgdev, bo, params,
ents, nents);
} else if (params->virgl) {
virtio_gpu_cmd_resource_create_3d(vgdev, bo, params,
objs, fence);
virtio_gpu_object_attach(vgdev, bo, ents, nents);
} else {
virtio_gpu_cmd_create_resource(vgdev, bo, params,
objs, fence);
virtio_gpu_object_attach(vgdev, bo, ents, nents);
}
*bo_ptr = bo;
return 0;
err_put_objs:
virtio_gpu_array_put_free(objs);
err_put_id:
virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
err_free_gem:
drm_gem_shmem_free_object(&shmem_obj->base);
return ret;
}