Re: [PATCH v3 1/2] drm/virtio: Refactor job submission code path

From: Rob Clark
Date: Thu Mar 23 2023 - 16:58:57 EST


On Thu, Mar 23, 2023 at 12:05 PM Dmitry Osipenko
<dmitry.osipenko@xxxxxxxxxxxxx> wrote:
>
> Move virtio_gpu_execbuffer_ioctl() into separate virtgpu_submit.c file
> and refactor the code along the way to ease addition of new features to
> the ioctl.
>
> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>

Reviewed-by: Rob Clark <robdclark@xxxxxxxxx>

> ---
> drivers/gpu/drm/virtio/Makefile | 2 +-
> drivers/gpu/drm/virtio/virtgpu_drv.h | 4 +
> drivers/gpu/drm/virtio/virtgpu_ioctl.c | 182 --------------
> drivers/gpu/drm/virtio/virtgpu_submit.c | 302 ++++++++++++++++++++++++
> 4 files changed, 307 insertions(+), 183 deletions(-)
> create mode 100644 drivers/gpu/drm/virtio/virtgpu_submit.c
>
> diff --git a/drivers/gpu/drm/virtio/Makefile b/drivers/gpu/drm/virtio/Makefile
> index b99fa4a73b68..d2e1788a8227 100644
> --- a/drivers/gpu/drm/virtio/Makefile
> +++ b/drivers/gpu/drm/virtio/Makefile
> @@ -6,6 +6,6 @@
> virtio-gpu-y := virtgpu_drv.o virtgpu_kms.o virtgpu_gem.o virtgpu_vram.o \
> virtgpu_display.o virtgpu_vq.o \
> virtgpu_fence.o virtgpu_object.o virtgpu_debugfs.o virtgpu_plane.o \
> - virtgpu_ioctl.o virtgpu_prime.o virtgpu_trace_points.o
> + virtgpu_ioctl.o virtgpu_prime.o virtgpu_trace_points.o virtgpu_submit.o
>
> obj-$(CONFIG_DRM_VIRTIO_GPU) += virtio-gpu.o
> diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
> index af6ffb696086..4126c384286b 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_drv.h
> +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
> @@ -486,4 +486,8 @@ void virtio_gpu_vram_unmap_dma_buf(struct device *dev,
> struct sg_table *sgt,
> enum dma_data_direction dir);
>
> +/* virtgpu_submit.c */
> +int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data,
> + struct drm_file *file);
> +
> #endif
> diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
> index da45215a933d..b24b11f25197 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
> @@ -38,36 +38,6 @@
> VIRTGPU_BLOB_FLAG_USE_SHAREABLE | \
> VIRTGPU_BLOB_FLAG_USE_CROSS_DEVICE)
>
> -static int virtio_gpu_fence_event_create(struct drm_device *dev,
> - struct drm_file *file,
> - struct virtio_gpu_fence *fence,
> - uint32_t ring_idx)
> -{
> - struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
> - struct virtio_gpu_fence_event *e = NULL;
> - int ret;
> -
> - if (!(vfpriv->ring_idx_mask & BIT_ULL(ring_idx)))
> - return 0;
> -
> - e = kzalloc(sizeof(*e), GFP_KERNEL);
> - if (!e)
> - return -ENOMEM;
> -
> - e->event.type = VIRTGPU_EVENT_FENCE_SIGNALED;
> - e->event.length = sizeof(e->event);
> -
> - ret = drm_event_reserve_init(dev, file, &e->base, &e->event);
> - if (ret)
> - goto free;
> -
> - fence->e = e;
> - return 0;
> -free:
> - kfree(e);
> - return ret;
> -}
> -
> /* Must be called with &virtio_gpu_fpriv.struct_mutex held. */
> static void virtio_gpu_create_context_locked(struct virtio_gpu_device *vgdev,
> struct virtio_gpu_fpriv *vfpriv)
> @@ -108,158 +78,6 @@ static int virtio_gpu_map_ioctl(struct drm_device *dev, void *data,
> &virtio_gpu_map->offset);
> }
>
> -/*
> - * Usage of execbuffer:
> - * Relocations need to take into account the full VIRTIO_GPUDrawable size.
> - * However, the command as passed from user space must *not* contain the initial
> - * VIRTIO_GPUReleaseInfo struct (first XXX bytes)
> - */
> -static int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data,
> - struct drm_file *file)
> -{
> - struct drm_virtgpu_execbuffer *exbuf = data;
> - struct virtio_gpu_device *vgdev = dev->dev_private;
> - struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
> - struct virtio_gpu_fence *out_fence;
> - int ret;
> - uint32_t *bo_handles = NULL;
> - void __user *user_bo_handles = NULL;
> - struct virtio_gpu_object_array *buflist = NULL;
> - struct sync_file *sync_file;
> - int out_fence_fd = -1;
> - void *buf;
> - uint64_t fence_ctx;
> - uint32_t ring_idx;
> -
> - fence_ctx = vgdev->fence_drv.context;
> - ring_idx = 0;
> -
> - if (vgdev->has_virgl_3d == false)
> - return -ENOSYS;
> -
> - if ((exbuf->flags & ~VIRTGPU_EXECBUF_FLAGS))
> - return -EINVAL;
> -
> - if ((exbuf->flags & VIRTGPU_EXECBUF_RING_IDX)) {
> - if (exbuf->ring_idx >= vfpriv->num_rings)
> - return -EINVAL;
> -
> - if (!vfpriv->base_fence_ctx)
> - return -EINVAL;
> -
> - fence_ctx = vfpriv->base_fence_ctx;
> - ring_idx = exbuf->ring_idx;
> - }
> -
> - virtio_gpu_create_context(dev, file);
> - if (exbuf->flags & VIRTGPU_EXECBUF_FENCE_FD_IN) {
> - struct dma_fence *in_fence;
> -
> - in_fence = sync_file_get_fence(exbuf->fence_fd);
> -
> - if (!in_fence)
> - return -EINVAL;
> -
> - /*
> - * Wait if the fence is from a foreign context, or if the fence
> - * array contains any fence from a foreign context.
> - */
> - ret = 0;
> - if (!dma_fence_match_context(in_fence, fence_ctx + ring_idx))
> - ret = dma_fence_wait(in_fence, true);
> -
> - dma_fence_put(in_fence);
> - if (ret)
> - return ret;
> - }
> -
> - if (exbuf->flags & VIRTGPU_EXECBUF_FENCE_FD_OUT) {
> - out_fence_fd = get_unused_fd_flags(O_CLOEXEC);
> - if (out_fence_fd < 0)
> - return out_fence_fd;
> - }
> -
> - if (exbuf->num_bo_handles) {
> - bo_handles = kvmalloc_array(exbuf->num_bo_handles,
> - sizeof(uint32_t), GFP_KERNEL);
> - if (!bo_handles) {
> - ret = -ENOMEM;
> - goto out_unused_fd;
> - }
> -
> - user_bo_handles = u64_to_user_ptr(exbuf->bo_handles);
> - if (copy_from_user(bo_handles, user_bo_handles,
> - exbuf->num_bo_handles * sizeof(uint32_t))) {
> - ret = -EFAULT;
> - goto out_unused_fd;
> - }
> -
> - buflist = virtio_gpu_array_from_handles(file, bo_handles,
> - exbuf->num_bo_handles);
> - if (!buflist) {
> - ret = -ENOENT;
> - goto out_unused_fd;
> - }
> - kvfree(bo_handles);
> - bo_handles = NULL;
> - }
> -
> - buf = vmemdup_user(u64_to_user_ptr(exbuf->command), exbuf->size);
> - if (IS_ERR(buf)) {
> - ret = PTR_ERR(buf);
> - goto out_unused_fd;
> - }
> -
> - if (buflist) {
> - ret = virtio_gpu_array_lock_resv(buflist);
> - if (ret)
> - goto out_memdup;
> - }
> -
> - out_fence = virtio_gpu_fence_alloc(vgdev, fence_ctx, ring_idx);
> - if(!out_fence) {
> - ret = -ENOMEM;
> - goto out_unresv;
> - }
> -
> - ret = virtio_gpu_fence_event_create(dev, file, out_fence, ring_idx);
> - if (ret)
> - goto out_unresv;
> -
> - if (out_fence_fd >= 0) {
> - sync_file = sync_file_create(&out_fence->f);
> - if (!sync_file) {
> - dma_fence_put(&out_fence->f);
> - ret = -ENOMEM;
> - goto out_unresv;
> - }
> -
> - exbuf->fence_fd = out_fence_fd;
> - fd_install(out_fence_fd, sync_file->file);
> - }
> -
> - virtio_gpu_cmd_submit(vgdev, buf, exbuf->size,
> - vfpriv->ctx_id, buflist, out_fence);
> - dma_fence_put(&out_fence->f);
> - virtio_gpu_notify(vgdev);
> - return 0;
> -
> -out_unresv:
> - if (buflist)
> - virtio_gpu_array_unlock_resv(buflist);
> -out_memdup:
> - kvfree(buf);
> -out_unused_fd:
> - kvfree(bo_handles);
> - if (buflist)
> - virtio_gpu_array_put_free(buflist);
> -
> - if (out_fence_fd >= 0)
> - put_unused_fd(out_fence_fd);
> -
> - return ret;
> -}
> -
> static int virtio_gpu_getparam_ioctl(struct drm_device *dev, void *data,
> struct drm_file *file)
> {
> diff --git a/drivers/gpu/drm/virtio/virtgpu_submit.c b/drivers/gpu/drm/virtio/virtgpu_submit.c
> new file mode 100644
> index 000000000000..2ce2459c6bc2
> --- /dev/null
> +++ b/drivers/gpu/drm/virtio/virtgpu_submit.c
> @@ -0,0 +1,302 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright (C) 2015 Red Hat, Inc.
> + * All Rights Reserved.
> + *
> + * Authors:
> + * Dave Airlie
> + * Alon Levy
> + */
> +
> +#include <linux/dma-fence-unwrap.h>
> +#include <linux/file.h>
> +#include <linux/sync_file.h>
> +#include <linux/uaccess.h>
> +
> +#include <drm/drm_file.h>
> +#include <drm/virtgpu_drm.h>
> +
> +#include "virtgpu_drv.h"
> +
> +struct virtio_gpu_submit {
> + struct virtio_gpu_object_array *buflist;
> + struct drm_virtgpu_execbuffer *exbuf;
> + struct virtio_gpu_fence *out_fence;
> + struct virtio_gpu_fpriv *vfpriv;
> + struct virtio_gpu_device *vgdev;
> + struct drm_file *file;
> + uint64_t fence_ctx;
> + uint32_t ring_idx;
> + int out_fence_fd;
> + void *buf;
> +};
> +
> +static int virtio_gpu_do_fence_wait(struct virtio_gpu_submit *submit,
> + struct dma_fence *in_fence)
> +{
> + uint32_t context = submit->fence_ctx + submit->ring_idx;
> +
> + if (dma_fence_match_context(in_fence, context))
> + return 0;
> +
> + return dma_fence_wait(in_fence, true);
> +}
> +
> +static int virtio_gpu_dma_fence_wait(struct virtio_gpu_submit *submit,
> + struct dma_fence *fence)
> +{
> + struct dma_fence_unwrap itr;
> + struct dma_fence *f;
> + int err;
> +
> + dma_fence_unwrap_for_each(f, &itr, fence) {
> + err = virtio_gpu_do_fence_wait(submit, f);
> + if (err)
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +static int virtio_gpu_fence_event_create(struct drm_device *dev,
> + struct drm_file *file,
> + struct virtio_gpu_fence *fence,
> + uint32_t ring_idx)
> +{
> + struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
> + struct virtio_gpu_fence_event *e = NULL;
> + int ret;
> +
> + if (!(vfpriv->ring_idx_mask & BIT_ULL(ring_idx)))
> + return 0;
> +
> + e = kzalloc(sizeof(*e), GFP_KERNEL);
> + if (!e)
> + return -ENOMEM;
> +
> + e->event.type = VIRTGPU_EVENT_FENCE_SIGNALED;
> + e->event.length = sizeof(e->event);
> +
> + ret = drm_event_reserve_init(dev, file, &e->base, &e->event);
> + if (ret) {
> + kfree(e);
> + return ret;
> + }
> +
> + fence->e = e;
> +
> + return 0;
> +}
> +
> +static int virtio_gpu_init_submit_buflist(struct virtio_gpu_submit *submit)
> +{
> + struct drm_virtgpu_execbuffer *exbuf = submit->exbuf;
> + uint32_t *bo_handles;
> +
> + if (!exbuf->num_bo_handles)
> + return 0;
> +
> + bo_handles = kvmalloc_array(exbuf->num_bo_handles, sizeof(uint32_t),
> + GFP_KERNEL);
> + if (!bo_handles)
> + return -ENOMEM;
> +
> + if (copy_from_user(bo_handles, u64_to_user_ptr(exbuf->bo_handles),
> + exbuf->num_bo_handles * sizeof(uint32_t))) {
> + kvfree(bo_handles);
> + return -EFAULT;
> + }
> +
> + submit->buflist = virtio_gpu_array_from_handles(submit->file, bo_handles,
> + exbuf->num_bo_handles);
> + if (!submit->buflist) {
> + kvfree(bo_handles);
> + return -ENOENT;
> + }
> +
> + kvfree(bo_handles);
> +
> + return 0;
> +}
> +
> +static void virtio_gpu_cleanup_submit(struct virtio_gpu_submit *submit)
> +{
> + if (!IS_ERR(submit->buf))
> + kvfree(submit->buf);
> +
> + if (submit->buflist)
> + virtio_gpu_array_put_free(submit->buflist);
> +
> + if (submit->out_fence_fd >= 0)
> + put_unused_fd(submit->out_fence_fd);
> +
> + if (submit->out_fence)
> + dma_fence_put(&submit->out_fence->f);
> +}
> +
> +static void virtio_gpu_submit(struct virtio_gpu_submit *submit)
> +{
> + virtio_gpu_cmd_submit(submit->vgdev, submit->buf, submit->exbuf->size,
> + submit->vfpriv->ctx_id, submit->buflist,
> + submit->out_fence);
> + virtio_gpu_notify(submit->vgdev);
> +}
> +
> +static void virtio_gpu_complete_submit(struct virtio_gpu_submit *submit)
> +{
> + submit->buf = NULL;
> + submit->buflist = NULL;
> + submit->out_fence = NULL;
> + submit->out_fence_fd = -1;
> +}
> +
> +static int virtio_gpu_init_submit(struct virtio_gpu_submit *submit,
> + struct drm_virtgpu_execbuffer *exbuf,
> + struct drm_device *dev,
> + struct drm_file *file,
> + uint64_t fence_ctx, uint32_t ring_idx)
> +{
> + struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
> + struct virtio_gpu_device *vgdev = dev->dev_private;
> + struct virtio_gpu_fence *out_fence;
> + int err;
> +
> + memset(submit, 0, sizeof(*submit));
> +
> + out_fence = virtio_gpu_fence_alloc(vgdev, fence_ctx, ring_idx);
> + if (!out_fence)
> + return -ENOMEM;
> +
> + err = virtio_gpu_fence_event_create(dev, file, out_fence, ring_idx);
> + if (err) {
> + dma_fence_put(&out_fence->f);
> + return err;
> + }
> +
> + submit->out_fence = out_fence;
> + submit->fence_ctx = fence_ctx;
> + submit->ring_idx = ring_idx;
> + submit->out_fence_fd = -1;
> + submit->vfpriv = vfpriv;
> + submit->vgdev = vgdev;
> + submit->exbuf = exbuf;
> + submit->file = file;
> +
> + err = virtio_gpu_init_submit_buflist(submit);
> + if (err)
> + return err;
> +
> + submit->buf = vmemdup_user(u64_to_user_ptr(exbuf->command), exbuf->size);
> + if (IS_ERR(submit->buf))
> + return PTR_ERR(submit->buf);
> +
> + if (exbuf->flags & VIRTGPU_EXECBUF_FENCE_FD_OUT) {
> + err = get_unused_fd_flags(O_CLOEXEC);
> + if (err < 0)
> + return err;
> +
> + submit->out_fence_fd = err;
> + }
> +
> + return 0;
> +}
> +
> +static int virtio_gpu_wait_in_fence(struct virtio_gpu_submit *submit)
> +{
> + int ret = 0;
> +
> + if (submit->exbuf->flags & VIRTGPU_EXECBUF_FENCE_FD_IN) {
> + struct dma_fence *in_fence =
> + sync_file_get_fence(submit->exbuf->fence_fd);
> + if (!in_fence)
> + return -EINVAL;
> +
> + /*
> + * Wait if the fence is from a foreign context, or if the fence
> + * array contains any fence from a foreign context.
> + */
> + ret = virtio_gpu_dma_fence_wait(submit, in_fence);
> +
> + dma_fence_put(in_fence);
> + }
> +
> + return ret;
> +}
> +
> +static int virtio_gpu_install_out_fence_fd(struct virtio_gpu_submit *submit)
> +{
> + if (submit->out_fence_fd >= 0) {
> + struct sync_file *sync_file =
> + sync_file_create(&submit->out_fence->f);
> + if (!sync_file)
> + return -ENOMEM;
> +
> + submit->exbuf->fence_fd = submit->out_fence_fd;
> + fd_install(submit->out_fence_fd, sync_file->file);
> + }
> +
> + return 0;
> +}
> +
> +static int virtio_gpu_lock_buflist(struct virtio_gpu_submit *submit)
> +{
> + if (submit->buflist)
> + return virtio_gpu_array_lock_resv(submit->buflist);
> +
> + return 0;
> +}
> +
> +int virtio_gpu_execbuffer_ioctl(struct drm_device *dev, void *data,
> + struct drm_file *file)
> +{
> + struct virtio_gpu_device *vgdev = dev->dev_private;
> + struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
> + uint64_t fence_ctx = vgdev->fence_drv.context;
> + struct drm_virtgpu_execbuffer *exbuf = data;
> + struct virtio_gpu_submit submit;
> + uint32_t ring_idx = 0;
> + int ret = -EINVAL;
> +
> + if (vgdev->has_virgl_3d == false)
> + return -ENOSYS;
> +
> + if ((exbuf->flags & ~VIRTGPU_EXECBUF_FLAGS))
> + return ret;
> +
> + if ((exbuf->flags & VIRTGPU_EXECBUF_RING_IDX)) {
> + if (exbuf->ring_idx >= vfpriv->num_rings)
> + return ret;
> +
> + if (!vfpriv->base_fence_ctx)
> + return ret;
> +
> + fence_ctx = vfpriv->base_fence_ctx;
> + ring_idx = exbuf->ring_idx;
> + }
> +
> + virtio_gpu_create_context(dev, file);
> +
> + ret = virtio_gpu_init_submit(&submit, exbuf, dev, file,
> + fence_ctx, ring_idx);
> + if (ret)
> + goto cleanup;
> +
> + ret = virtio_gpu_wait_in_fence(&submit);
> + if (ret)
> + goto cleanup;
> +
> + ret = virtio_gpu_install_out_fence_fd(&submit);
> + if (ret)
> + goto cleanup;
> +
> + ret = virtio_gpu_lock_buflist(&submit);
> + if (ret)
> + goto cleanup;
> +
> + virtio_gpu_submit(&submit);
> + virtio_gpu_complete_submit(&submit);
> +cleanup:
> + virtio_gpu_cleanup_submit(&submit);
> +
> + return ret;
> +}
> --
> 2.39.2
>