Re: [PATCH v2 3/4] drm/v3d: add generic ioctl extension

O 09/30, Iago Toral wrote:

On Wed, 2021-09-29 at 10:44 +0100, Melissa Wen wrote:

...

Add support to attach generic extensions on job submission. This patch is third prep work to enable multiple syncobjs on job submission. With this work, when the job submission interface needs to be extended to accomodate a new feature, we will use a generic extension struct where an id determines the data type to be pointed. The first application is to enable multiples in/out syncobj (next patch), but the base is already done for future features. Therefore, to attach a new feature, a specific extension struct should subclass drm_v3d_extension and update the list of extensions in a job submission.

v2:

• remove redundant elements to subclass struct (Daniel)

Signed-off-by: Melissa Wen mwen@igalia.com

drivers/gpu/drm/v3d/v3d_drv.c | 4 +- drivers/gpu/drm/v3d/v3d_gem.c | 71 +++++++++++++++++++++++++++++++++-- include/uapi/drm/v3d_drm.h | 31 +++++++++++++++ 3 files changed, 100 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/v3d/v3d_drv.c b/drivers/gpu/drm/v3d/v3d_drv.c index c1deab2cf38d..3d6b9bcce2f7 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.c +++ b/drivers/gpu/drm/v3d/v3d_drv.c @@ -83,7 +83,6 @@ static int v3d_get_param_ioctl(struct drm_device *dev, void *data, return 0; }

• switch (args->param) { case DRM_V3D_PARAM_SUPPORTS_TFU: args->value = 1;

@@ -147,7 +146,7 @@ v3d_postclose(struct drm_device *dev, struct drm_file *file) DEFINE_DRM_GEM_FOPS(v3d_drm_fops);

/* DRM_AUTH is required on SUBMIT_CL for now, while we don't have GMP

• • protection between clients. Note that render nodes would be be

• • protection between clients. Note that render nodes would be
  • able to submit CLs that could access BOs from clients

authenticated

• with the master node. The TFU doesn't use the GMP, so it would
• need to stay DRM_AUTH until we do buffer size/offset validation.

@@ -219,7 +218,6 @@ static int v3d_platform_drm_probe(struct platform_device *pdev) u32 mmu_debug; u32 ident1;

• v3d = devm_drm_dev_alloc(dev, &v3d_drm_driver, struct v3d_dev,

drm); if (IS_ERR(v3d)) return PTR_ERR(v3d); diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 9cfa6f8d4357..b912419027f7 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -535,6 +535,33 @@ v3d_attach_fences_and_unlock_reservation(struct drm_file *file_priv, } }

+static int +v3d_get_extensions(struct drm_file *file_priv, u64 ext_handles) +{

• struct drm_v3d_extension __user *user_ext;
• user_ext = u64_to_user_ptr(ext_handles);
• while(user_ext) {

• struct drm_v3d_extension ext;
  

• if (copy_from_user(&ext, user_ext, sizeof(ext))) {
  

• 	DRM_DEBUG("Failed to copy submit extension\n");
  

• 	return -EFAULT;
  

• }
  

• switch (ext.id) {
  

• case 0:
  

• default:
  

• 	DRM_DEBUG_DRIVER("Unknown extension id: %d\n",
  

ext.id);

• 	return -EINVAL;
  

• }
  

• user_ext = u64_to_user_ptr(ext.next);
  

• }
• return 0;

+}

/**

• v3d_submit_cl_ioctl() - Submits a job (frame) to the V3D.
• @dev: DRM device

@@ -563,15 +590,24 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,

trace_v3d_submit_cl_ioctl(&v3d->drm, args->rcl_start, args-

...

rcl_end);

• if (args->pad != 0)

• if (args->pad) return -EINVAL;

• if (args->flags != 0 &&

•    args->flags != DRM_V3D_SUBMIT_CL_FLUSH_CACHE) {
  

• if (args->flags &&

•    args->flags & ~(DRM_V3D_SUBMIT_CL_FLUSH_CACHE |
  

• 	    DRM_V3D_SUBMIT_EXTENSION)) {
  

  DRM_INFO("invalid flags: %d\n", args->flags); return -EINVAL; }

• if (args->flags & DRM_V3D_SUBMIT_EXTENSION) {

• ret = v3d_get_extensions(file_priv, args->extensions);
  

• if (ret) {
  

• 	DRM_DEBUG("Failed to get extensions.\n");
  

• 	return ret;
  

• }
  

• }

• ret = v3d_job_init(v3d, file_priv, (void *)&render,

sizeof(*render), v3d_render_job_free, args->in_sync_bcl, V3D_RENDER); if (ret) @@ -700,6 +736,19 @@ v3d_submit_tfu_ioctl(struct drm_device *dev, void *data,

trace_v3d_submit_tfu_ioctl(&v3d->drm, args->iia);

• if (args->flags && !(args->flags & DRM_V3D_SUBMIT_EXTENSION)) {

• DRM_DEBUG("invalid flags: %d\n", args->flags);
  

• return -EINVAL;
  

• }
• if (args->flags & DRM_V3D_SUBMIT_EXTENSION) {

• ret = v3d_get_extensions(file_priv, args->extensions);
  

• if (ret) {
  

• 	DRM_DEBUG("Failed to get extensions.\n");
  

• 	return ret;
  

• }
  

• }
• ret = v3d_job_init(v3d, file_priv, (void *)&job, sizeof(*job), v3d_job_free, args->in_sync, V3D_TFU); if (ret)

@@ -784,11 +833,27 @@ v3d_submit_csd_ioctl(struct drm_device *dev, void *data,

trace_v3d_submit_csd_ioctl(&v3d->drm, args->cfg[5], args-

...

cfg[6]);

• if (args->pad)

• return -EINVAL;
  

• if (!v3d_has_csd(v3d)) { DRM_DEBUG("Attempting CSD submit on non-CSD

hardware\n"); return -EINVAL; }

• if (args->flags && !(args->flags & DRM_V3D_SUBMIT_EXTENSION)) {

• DRM_INFO("invalid flags: %d\n", args->flags);
  

• return -EINVAL;
  

• }
• if (args->flags & DRM_V3D_SUBMIT_EXTENSION) {

• ret = v3d_get_extensions(file_priv, args->extensions);
  

• if (ret) {
  

• 	DRM_DEBUG("Failed to get extensions.\n");
  

• 	return ret;
  

• }
  

• }
• ret = v3d_job_init(v3d, file_priv, (void *)&job, sizeof(*job), v3d_job_free, args->in_sync, V3D_CSD); if (ret)

diff --git a/include/uapi/drm/v3d_drm.h b/include/uapi/drm/v3d_drm.h index 4104f22fb3d3..55b443ca6c0b 100644 --- a/include/uapi/drm/v3d_drm.h +++ b/include/uapi/drm/v3d_drm.h @@ -58,6 +58,20 @@ extern "C" { struct drm_v3d_perfmon_get_values)

#define DRM_V3D_SUBMIT_CL_FLUSH_CACHE 0x01 +#define DRM_V3D_SUBMIT_EXTENSION 0x02

+/* struct drm_v3d_extension - ioctl extensions

• • Linked-list of generic extensions where the id identify which

struct is

• • pointed by ext_data. Therefore, DRM_V3D_EXT_ID_* is used on id to

identify

• • the extension type.
• */

+struct drm_v3d_extension {

• __u64 next;
• __u32 id;

+#define DRM_V3D_EXT_ID_MULTI_SYNC 0x01

• __u32 flags; /* mbz */

+};

/**

• struct drm_v3d_submit_cl - ioctl argument for submitting commands

to the 3D @@ -135,12 +149,16 @@ struct drm_v3d_submit_cl { /* Number of BO handles passed in (size is that times 4). */ __u32 bo_handle_count;

• /* DRM_V3D_SUBMIT_* properties */ __u32 flags;

  /* ID of the perfmon to attach to this job. 0 means no perfmon.

*/ __u32 perfmon_id;

__u32 pad;

• /* Pointer to an array of ioctl extensions*/
• __u64 extensions;

};

/** @@ -248,6 +266,12 @@ struct drm_v3d_submit_tfu { __u32 in_sync; /* Sync object to signal when the TFU job is done. */ __u32 out_sync;

• __u32 flags;
• /* Pointer to an array of ioctl extensions*/
• __u64 extensions;

We want __u64 fields aligned to 64-bit so we should swap the positions of flags and extensions.

hmm.. not sure. before two arrays of 4 x _u32 elements, we have seven _u32 elements... this is why I counted a odd number of _u32 and put _u32 flags before _u64 extensions... or is it working different for array types?

For the same reason, I think there is an unalignment issue on submit_csd that would need to change the current interface to solve (afaiu)...

...

};

/* Submits a compute shader for dispatch. This job will block on any @@ -276,6 +300,13 @@ struct drm_v3d_submit_csd {

/* ID of the perfmon to attach to this job. 0 means no perfmon. */ __u32 perfmon_id;

• /* Pointer to an array of ioctl extensions*/
• __u64 extensions;
• __u32 flags;
• __u32 pad;

};

enum {