[PATCH RFC 07/12] vdpa_sim: move config management outside of the core

From: Stefano Garzarella
Date: Fri Nov 13 2020 - 08:48:17 EST


In order to simplify the code of the vdpa_sim core, we move the
config management in each device simulator.

The device must provide the size of config structure and a callback
to update this structure called during the vdpasim_set_features().

Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim.h | 5 +++--
drivers/vdpa/vdpa_sim/vdpa_sim.c | 29 +++++-----------------------
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 27 ++++++++++++++++----------
drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 12 ++++++++++++
4 files changed, 37 insertions(+), 36 deletions(-)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h
index 76e642042eb0..f7e1fe0a88d3 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
@@ -10,8 +10,6 @@
#include <linux/vdpa.h>
#include <linux/vhost_iotlb.h>
#include <uapi/linux/virtio_config.h>
-#include <uapi/linux/virtio_net.h>
-#include <uapi/linux/virtio_blk.h>

#define DRV_VERSION "0.1"
#define DRV_AUTHOR "Jason Wang <jasowang@xxxxxxxxxx>"
@@ -42,8 +40,11 @@ struct vdpasim_virtqueue {

struct vdpasim_device {
u64 supported_features;
+ size_t config_size;
u32 id;
int nvqs;
+
+ void (*update_config)(struct vdpasim *vdpasim);
};

struct vdpasim_init_attr {
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index d053bd14b3f8..9c29c2013661 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -185,14 +185,8 @@ struct vdpasim *vdpasim_create(struct vdpasim_init_attr *attr)
{
const struct vdpa_config_ops *ops;
struct vdpasim *vdpasim;
- u32 device_id;
struct device *dev;
- int i, size, ret = -ENOMEM;
-
- device_id = attr->device.id;
- /* Currently, we only accept the network and block devices. */
- if (device_id != VIRTIO_ID_NET && device_id != VIRTIO_ID_BLOCK)
- return ERR_PTR(-EOPNOTSUPP);
+ int i, ret = -ENOMEM;

if (attr->batch_mapping)
ops = &vdpasim_batch_config_ops;
@@ -206,11 +200,7 @@ struct vdpasim *vdpasim_create(struct vdpasim_init_attr *attr)

vdpasim->device = attr->device;

- if (device_id == VIRTIO_ID_NET)
- size = sizeof(struct virtio_net_config);
- else
- size = sizeof(struct virtio_blk_config);
- vdpasim->config = kzalloc(size, GFP_KERNEL);
+ vdpasim->config = kzalloc(vdpasim->device.config_size, GFP_KERNEL);
if (!vdpasim->config)
goto err_iommu;

@@ -364,13 +354,8 @@ static int vdpasim_set_features(struct vdpa_device *vdpa, u64 features)
* Note: We actually require VIRTIO_F_ACCESS_PLATFORM above which
* implies VIRTIO_F_VERSION_1, but let's not try to be clever here.
*/
- if (vdpasim->device.id == VIRTIO_ID_NET) {
- struct virtio_net_config *config =
- (struct virtio_net_config *)vdpasim->config;
-
- config->mtu = cpu_to_vdpasim16(vdpasim, 1500);
- config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP);
- }
+ if (vdpasim->device.update_config)
+ vdpasim->device.update_config(vdpasim);

return 0;
}
@@ -426,11 +411,7 @@ static void vdpasim_get_config(struct vdpa_device *vdpa, unsigned int offset,
{
struct vdpasim *vdpasim = vdpa_to_sim(vdpa);

- if (vdpasim->device.id == VIRTIO_ID_BLOCK &&
- (offset + len < sizeof(struct virtio_blk_config)))
- memcpy(buf, vdpasim->config + offset, len);
- else if (vdpasim->device.id == VIRTIO_ID_NET &&
- (offset + len < sizeof(struct virtio_net_config)))
+ if (offset + len < vdpasim->device.config_size)
memcpy(buf, vdpasim->config + offset, len);
}

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
index 363273d72e26..f456a0e4e097 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
@@ -7,6 +7,7 @@
*/

#include <linux/module.h>
+#include <uapi/linux/virtio_blk.h>

#include "vdpa_sim.h"

@@ -72,16 +73,31 @@ static void vdpasim_blk_work(struct work_struct *work)

}

+static void vdpasim_blk_update_config(struct vdpasim *vdpasim)
+{
+ struct virtio_blk_config *config =
+ (struct virtio_blk_config *)vdpasim->config;
+
+ config->capacity = cpu_to_vdpasim64(vdpasim, VDPASIM_BLK_CAPACITY);
+ config->size_max = cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_SIZE_MAX);
+ config->seg_max = cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_SEG_MAX);
+ config->num_queues = cpu_to_vdpasim16(vdpasim, VDPASIM_BLK_VQ_NUM);
+ config->min_io_size = cpu_to_vdpasim16(vdpasim, 1);
+ config->opt_io_size = cpu_to_vdpasim32(vdpasim, 1);
+ config->blk_size = cpu_to_vdpasim32(vdpasim, 512);
+}
+
static int __init vdpasim_blk_init(void)
{
struct vdpasim_init_attr attr = {};
- struct virtio_blk_config *config;
int ret;

attr.device.id = VIRTIO_ID_BLOCK;
attr.device.supported_features = VDPASIM_FEATURES |
VDPASIM_BLK_FEATURES;
attr.device.nvqs = VDPASIM_BLK_VQ_NUM;
+ attr.device.config_size = sizeof(struct virtio_blk_config);
+ attr.device.update_config = vdpasim_blk_update_config;

attr.work_fn = vdpasim_blk_work;

@@ -91,15 +107,6 @@ static int __init vdpasim_blk_init(void)
goto out;
}

- config = (struct virtio_blk_config *)vdpasim_blk_dev->config;
- config->capacity = cpu_to_vdpasim64(vdpasim_blk_dev, VDPASIM_BLK_CAPACITY);
- config->size_max = cpu_to_vdpasim32(vdpasim_blk_dev, VDPASIM_BLK_SIZE_MAX);
- config->seg_max = cpu_to_vdpasim32(vdpasim_blk_dev, VDPASIM_BLK_SEG_MAX);
- config->num_queues = cpu_to_vdpasim16(vdpasim_blk_dev, VDPASIM_BLK_VQ_NUM);
- config->min_io_size = cpu_to_vdpasim16(vdpasim_blk_dev, 1);
- config->opt_io_size = cpu_to_vdpasim32(vdpasim_blk_dev, 1);
- config->blk_size = cpu_to_vdpasim32(vdpasim_blk_dev, 512);
-
ret = vdpa_register_device(&vdpasim_blk_dev->vdpa);
if (ret)
goto put_dev;
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
index 88c9569f6bd3..b9372fdf2415 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
@@ -9,6 +9,7 @@

#include <linux/module.h>
#include <linux/etherdevice.h>
+#include <uapi/linux/virtio_net.h>

#include "vdpa_sim.h"

@@ -99,6 +100,15 @@ static void vdpasim_net_work(struct work_struct *work)
spin_unlock(&vdpasim->lock);
}

+static void vdpasim_net_update_config(struct vdpasim *vdpasim)
+{
+ struct virtio_net_config *config =
+ (struct virtio_net_config *)vdpasim->config;
+
+ config->mtu = cpu_to_vdpasim16(vdpasim, 1500);
+ config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP);
+}
+
static int __init vdpasim_net_init(void)
{
struct vdpasim_init_attr attr = {};
@@ -109,6 +119,8 @@ static int __init vdpasim_net_init(void)
attr.device.supported_features = VDPASIM_FEATURES |
VDPASIM_NET_FEATURES;
attr.device.nvqs = VDPASIM_NET_VQ_NUM;
+ attr.device.config_size = sizeof(struct virtio_net_config);
+ attr.device.update_config = vdpasim_net_update_config;

attr.work_fn = vdpasim_net_work;
attr.batch_mapping = batch_mapping;
--
2.26.2