Re: [PATCH 1/4] drivers: hv: dxgkrnl: core code

Greg KH
2020-08-14T13:03:49Z

On Fri, Aug 14, 2020 at 08:38:53AM -0400, Sasha Levin wrote:
> Add support for a Hyper-V based vGPU implementation that exposes the
> DirectX API to Linux userspace.
>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
> drivers/hv/dxgkrnl/Kconfig | 10 +
> drivers/hv/dxgkrnl/Makefile | 12 +
> drivers/hv/dxgkrnl/d3dkmthk.h | 1636 ++++++++++
> drivers/hv/dxgkrnl/dxgadapter.c | 1406 ++++++++
> drivers/hv/dxgkrnl/dxgkrnl.h | 927 ++++++
> drivers/hv/dxgkrnl/dxgmodule.c | 656 ++++
> drivers/hv/dxgkrnl/dxgprocess.c | 357 ++
> drivers/hv/dxgkrnl/dxgvmbus.c | 3084 ++++++++++++++++++
> drivers/hv/dxgkrnl/dxgvmbus.h | 873 +++++
> drivers/hv/dxgkrnl/hmgr.c | 604 ++++
> drivers/hv/dxgkrnl/hmgr.h | 112 +
> drivers/hv/dxgkrnl/ioctl.c | 5413 +++++++++++++++++++++++++++++++
> drivers/hv/dxgkrnl/misc.c | 279 ++
> drivers/hv/dxgkrnl/misc.h | 309 ++
> 14 files changed, 15678 insertions(+)

It's almost impossible to review 15k lines at once, please break this up
into reviewable chunks next time.

> +++ b/drivers/hv/dxgkrnl/Kconfig
> @@ -0,0 +1,10 @@
> +#
> +# dxgkrnl configuration
> +#
> +
> +config DXGKRNL
> + tristate "Microsoft virtual GPU support"
> + depends on HYPERV
> + help
> + This driver supports Microsoft virtual GPU.
> +

You need more text here, this isn't a staging driver submission :)

> diff --git a/drivers/hv/dxgkrnl/Makefile b/drivers/hv/dxgkrnl/Makefile
> new file mode 100644
> index 000000000000..11505a153d9d
> --- /dev/null
> +++ b/drivers/hv/dxgkrnl/Makefile
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0
> +# Makefile for the Linux video drivers.
> +# 5 Aug 1999, James Simmons, <mailto:jsimmons@users.sf.net>
> +# Rewritten to use lists instead of if-statements.

I really doubt these last 3 lines are relevant.

> +
> +# Each configuration option enables a list of files.

We know this.

> +
> +# Uncomment to enable printing debug messages by default
> +#ccflags-y := -DDEBUG

No, don't do this please.

> +
> +obj-$(CONFIG_DXGKRNL) += dxgkrnl.o
> +dxgkrnl-y := dxgmodule.o hmgr.o misc.o dxgadapter.o ioctl.o dxgvmbus.o dxgprocess.o
> diff --git a/drivers/hv/dxgkrnl/d3dkmthk.h b/drivers/hv/dxgkrnl/d3dkmthk.h
> new file mode 100644
> index 000000000000..90cf5134b361
> --- /dev/null
> +++ b/drivers/hv/dxgkrnl/d3dkmthk.h
> @@ -0,0 +1,1636 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/*
> + * Copyright (c) 2019, Microsoft Corporation.
> + *
> + * Author:
> + * Iouri Tarassov <iourit@microsoft.com>
> + *
> + * Dxgkrnl Graphics Port Driver user mode interface
> + *
> + */
> +
> +#ifndef _D3DKMTHK_H
> +#define _D3DKMTHK_H
> +
> +#include "misc.h"
> +
> +#define D3DDDI_MAX_WRITTEN_PRIMARIES 16
> +#define D3DDDI_MAX_MPO_PRESENT_DIRTY_RECTS 0xFFF
> +
> +#define D3DKMT_CREATEALLOCATION_MAX 1024
> +#define D3DKMT_ADAPTERS_MAX 64
> +#define D3DDDI_MAX_BROADCAST_CONTEXT 64
> +#define D3DDDI_MAX_OBJECT_WAITED_ON 32
> +#define D3DDDI_MAX_OBJECT_SIGNALED 32
> +
> +struct d3dkmt_adapterinfo {
> + struct d3dkmthandle adapter_handle;
> + struct winluid adapter_luid;
> + uint num_sources;
> + uint present_move_regions_preferred;
> +};
> +
> +struct d3dkmt_enumadapters2 {
> + uint num_adapters;

Use kernel types please, here and everywhere. u32?

> + struct d3dkmt_adapterinfo *adapters;
> +};
> +
> +struct d3dkmt_closeadapter {
> + struct d3dkmthandle adapter_handle;
> +};

A "handle"? And that has to be one of the most difficult structure
names ever :)

Why not just use the "handle" for the structure as obviously that's all
that is needed here.
> +
> +struct d3dkmt_openadapterfromluid {
> + struct winluid adapter_luid;
> + struct d3dkmthandle adapter_handle;
> +};
> +
> +struct d3dddi_allocationlist {
> + struct d3dkmthandle allocation;
> + union {
> + struct {
> + uint write_operation :1;
> + uint do_not_retire_instance :1;
> + uint offer_priority :3;
> + uint reserved :27;

endian issues?

If not, why are these bit fields?

> +struct d3dkmt_destroydevice {
> + struct d3dkmthandle device;
> +};

Again, single entity structures?

Are you trying to pass around "handles" and cast them backwards?

If so, great, but then use the real kernel structures for that like
'struct device' if these are actually devices.

> +
> +enum d3dkmt_clienthint {
> + D3DKMT_CLIENTHINT_UNKNOWN = 0,
> + D3DKMT_CLIENTHINT_OPENGL = 1,
> + D3DKMT_CLIENTHINT_CDD = 2,
> + D3DKMT_CLIENTHINT_DX7 = 7,
> + D3DKMT_CLIENTHINT_DX8 = 8,
> + D3DKMT_CLIENTHINT_DX9 = 9,
> + D3DKMT_CLIENTHINT_DX10 = 10,
> +};
> +
> +struct d3dddi_createcontextflags {
> + union {
> + struct {
> + uint null_rendering:1;
> + uint initial_data:1;
> + uint disable_gpu_timeout:1;
> + uint synchronization_only:1;
> + uint hw_queue_supported:1;
> + uint reserved:27;

Endian?

> + };
> + uint value;
> + };
> +};

<...>

> +static int dxgglobal_init_global_channel(struct hv_device *hdev)
> +{
> + int ret = 0;
> +
> + TRACE_DEBUG(1, "%s %x %x", __func__, hdev->vendor_id, hdev->device_id);
> + {
> + TRACE_DEBUG(1, "device type : %pUb\n", &hdev->dev_type);
> + TRACE_DEBUG(1, "device channel: %pUb %p primary: %p\n",
> + &hdev->channel->offermsg.offer.if_type,
> + hdev->channel, hdev->channel->primary_channel);
> + }
> +
> + if (dxgglobal->hdev) {
> + /* This device should appear only once */
> + pr_err("dxgglobal already initialized\n");
> + ret = -EBADE;
> + goto error;
> + }
> +
> + dxgglobal->hdev = hdev;
> +
> + ret = dxgvmbuschannel_init(&dxgglobal->channel, hdev);
> + if (ret) {
> + pr_err("dxgvmbuschannel_init failed: %d\n", ret);
> + goto error;
> + }
> +
> + ret = dxgglobal_getiospace(dxgglobal);
> + if (ret) {
> + pr_err("getiospace failed: %d\n", ret);
> + goto error;
> + }
> +
> + ret = dxgvmb_send_set_iospace_region(dxgglobal->mmiospace_base,
> + dxgglobal->mmiospace_size, 0);
> + if (ISERROR(ret)) {
> + pr_err("send_set_iospace_region failed");
> + goto error;

You forgot to unwind from the things you initialized above :(

> + }
> +
> + hv_set_drvdata(hdev, dxgglobal);
> +
> + dxgglobal->dxgdevice.minor = MISC_DYNAMIC_MINOR;
> + dxgglobal->dxgdevice.name = "dxg";
> + dxgglobal->dxgdevice.fops = &dxgk_fops;
> + dxgglobal->dxgdevice.mode = 0666;
> + ret = misc_register(&dxgglobal->dxgdevice);
> + if (ret) {
> + pr_err("misc_register failed: %d", ret);
> + goto error;

Again, no cleanups so you leak resources? Not nice :(

> + }
> + dxgglobaldev = dxgglobal->dxgdevice.this_device;
> + dxgglobal->device_initialized = true;
> +
> +error:
> + return ret;
> +}
> +
> +static void dxgglobal_destroy_global_channel(void)
> +{
> + dxglockorder_acquire(DXGLOCK_GLOBAL_CHANNEL);
> + down_write(&dxgglobal->channel_lock);
> +
> + TRACE_DEBUG(1, "%s", __func__);

ftrace is your friend :)