[RFC,14/29] nvkm/vgpu: introduce channel allocation for vGPU

Commit Message

Zhi Wang Sept. 22, 2024, 12:49 p.m. UTC

Creating a vGPU requires allocating a portion of the CHIDs from the
reserved channel pool.

Expose the routine of allocating the channels from the reserved channel
pool to NVIDIA vGPU VFIO module for creating a vGPU.

Signed-off-by: Zhi Wang <[e-mail]>
---
 .../nouveau/include/nvkm/vgpu_mgr/vgpu_mgr.h  |  2 ++
 drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vfio.c  | 28 +++++++++++++++++++
 .../gpu/drm/nouveau/nvkm/vgpu_mgr/vgpu_mgr.c  |  2 ++
 include/drm/nvkm_vgpu_mgr_vfio.h              |  2 ++
 4 files changed, 34 insertions(+)

Patch

diff --git a/drivers/gpu/drm/nouveau/include/nvkm/vgpu_mgr/vgpu_mgr.h b/drivers/gpu/drm/nouveau/include/nvkm/vgpu_mgr/vgpu_mgr.h
index 5a856fa905f9..a351e8bfc772 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/vgpu_mgr/vgpu_mgr.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/vgpu_mgr/vgpu_mgr.h
@@ -22,6 +22,8 @@  struct nvkm_vgpu_mgr {
 
 	void *vfio_ops;
 	struct nvidia_vgpu_vfio_handle_data vfio_handle_data;
+
+	struct mutex chid_alloc_lock;
 };
 
 bool nvkm_vgpu_mgr_is_supported(struct nvkm_device *device);
diff --git a/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vfio.c b/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vfio.c
index 9732e43a5d6b..44d901a0474d 100644
--- a/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vfio.c
+++ b/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vfio.c
@@ -1,6 +1,9 @@ 
 /* SPDX-License-Identifier: MIT */
 
 #include <core/device.h>
+#include <engine/chid.h>
+#include <engine/fifo.h>
+#include <subdev/fb.h>
 #include <subdev/gsp.h>
 
 #include <vgpu_mgr/vgpu_mgr.h>
@@ -128,6 +131,29 @@  static void rm_ctrl_done(struct nvidia_vgpu_gsp_client *client, void *ctrl)
 	nvkm_gsp_rm_ctrl_done(&device->subdevice, ctrl);
 }
 
+static void free_chids(void *handle, int offset, int count)
+{
+	struct nvkm_device *device = handle;
+	struct nvkm_vgpu_mgr *vgpu_mgr = &device->vgpu_mgr;
+
+	mutex_lock(&vgpu_mgr->chid_alloc_lock);
+	nvkm_chid_reserved_free(device->fifo->chid, offset, count);
+	mutex_unlock(&vgpu_mgr->chid_alloc_lock);
+}
+
+static int alloc_chids(void *handle, int count)
+{
+	struct nvkm_device *device = handle;
+	struct nvkm_vgpu_mgr *vgpu_mgr = &device->vgpu_mgr;
+	int ret;
+
+	mutex_lock(&vgpu_mgr->chid_alloc_lock);
+	ret = nvkm_chid_reserved_alloc(device->fifo->chid, count);
+	mutex_unlock(&vgpu_mgr->chid_alloc_lock);
+
+	return ret;
+}
+
 struct nvkm_vgpu_mgr_vfio_ops nvkm_vgpu_mgr_vfio_ops = {
 	.vgpu_mgr_is_enabled = vgpu_mgr_is_enabled,
 	.get_handle = get_handle,
@@ -140,6 +166,8 @@  struct nvkm_vgpu_mgr_vfio_ops nvkm_vgpu_mgr_vfio_ops = {
 	.rm_ctrl_wr = rm_ctrl_wr,
 	.rm_ctrl_rd = rm_ctrl_rd,
 	.rm_ctrl_done = rm_ctrl_done,
+	.alloc_chids = alloc_chids,
+	.free_chids = free_chids,
 };
 
 /**
diff --git a/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vgpu_mgr.c b/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vgpu_mgr.c
index caeb805cf1c3..3654bd43b68a 100644
--- a/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vgpu_mgr.c
+++ b/drivers/gpu/drm/nouveau/nvkm/vgpu_mgr/vgpu_mgr.c
@@ -127,6 +127,8 @@  int nvkm_vgpu_mgr_init(struct nvkm_device *device)
 
 	vgpu_mgr->nvkm_dev = device;
 
+	mutex_init(&vgpu_mgr->chid_alloc_lock);
+
 	ret = attach_nvkm(vgpu_mgr);
 	if (ret)
 		return ret;
diff --git a/include/drm/nvkm_vgpu_mgr_vfio.h b/include/drm/nvkm_vgpu_mgr_vfio.h
index 29ff9b39d0b2..001306fb0b5b 100644
--- a/include/drm/nvkm_vgpu_mgr_vfio.h
+++ b/include/drm/nvkm_vgpu_mgr_vfio.h
@@ -35,6 +35,8 @@  struct nvkm_vgpu_mgr_vfio_ops {
 			    u32 size);
 	void (*rm_ctrl_done)(struct nvidia_vgpu_gsp_client *client,
 			     void *ctrl);
+	int (*alloc_chids)(void *handle, int count);
+	void (*free_chids)(void *handle, int offset, int count);
 };
 
 struct nvkm_vgpu_mgr_vfio_ops *nvkm_vgpu_mgr_get_vfio_ops(void *handle);