[PATCH 5.10 05/29] vdpa_sim: add get_config callback in vdpasim_dev_attr
From: Greg Kroah-Hartman
Date: Mon Feb 22 2021 - 07:24:01 EST
From: Stefano Garzarella <sgarzare@xxxxxxxxxx>
commit 65b709586e222fa6ffd4166ac7fdb5d5dad113ee upstream.
The get_config callback can be used by the device to fill the
config structure.
The callback will be invoked in vdpasim_get_config() before copying
bytes into caller buffer.
Move vDPA-net config updates from vdpasim_set_features() in the
new vdpasim_net_get_config() callback.
This is safe since in vdpa_get_config() we already check that
.set_features() callback is called before .get_config().
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20201215144256.155342-13-sgarzare@xxxxxxxxxx
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim.c | 35 +++++++++++++++++++++--------------
1 file changed, 21 insertions(+), 14 deletions(-)
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -69,9 +69,12 @@ static u64 vdpasim_features = (1ULL << V
(1ULL << VIRTIO_F_ACCESS_PLATFORM) |
(1ULL << VIRTIO_NET_F_MAC);
+struct vdpasim;
+
struct vdpasim_dev_attr {
size_t config_size;
int nvqs;
+ void (*get_config)(struct vdpasim *vdpasim, void *config);
};
/* State of each vdpasim device */
@@ -524,8 +527,6 @@ static u64 vdpasim_get_features(struct v
static int vdpasim_set_features(struct vdpa_device *vdpa, u64 features)
{
struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
- struct virtio_net_config *config =
- (struct virtio_net_config *)vdpasim->config;
/* DMA mapping must be done by driver */
if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
@@ -533,16 +534,6 @@ static int vdpasim_set_features(struct v
vdpasim->features = features & vdpasim_features;
- /* We generally only know whether guest is using the legacy interface
- * here, so generally that's the earliest we can set config fields.
- * Note: We actually require VIRTIO_F_ACCESS_PLATFORM above which
- * implies VIRTIO_F_VERSION_1, but let's not try to be clever here.
- */
-
- config->mtu = cpu_to_vdpasim16(vdpasim, 1500);
- config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP);
- memcpy(config->mac, macaddr_buf, ETH_ALEN);
-
return 0;
}
@@ -595,8 +586,13 @@ static void vdpasim_get_config(struct vd
{
struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
- if (offset + len < vdpasim->dev_attr.config_size)
- memcpy(buf, vdpasim->config + offset, len);
+ if (offset + len > vdpasim->dev_attr.config_size)
+ return;
+
+ if (vdpasim->dev_attr.get_config)
+ vdpasim->dev_attr.get_config(vdpasim, vdpasim->config);
+
+ memcpy(buf, vdpasim->config + offset, len);
}
static void vdpasim_set_config(struct vdpa_device *vdpa, unsigned int offset,
@@ -739,12 +735,23 @@ static const struct vdpa_config_ops vdpa
.free = vdpasim_free,
};
+static void vdpasim_net_get_config(struct vdpasim *vdpasim, void *config)
+{
+ struct virtio_net_config *net_config =
+ (struct virtio_net_config *)config;
+
+ net_config->mtu = cpu_to_vdpasim16(vdpasim, 1500);
+ net_config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP);
+ memcpy(net_config->mac, macaddr_buf, ETH_ALEN);
+}
+
static int __init vdpasim_dev_init(void)
{
struct vdpasim_dev_attr dev_attr = {};
dev_attr.nvqs = VDPASIM_VQ_NUM;
dev_attr.config_size = sizeof(struct virtio_net_config);
+ dev_attr.get_config = vdpasim_net_get_config;
vdpasim_dev = vdpasim_create(&dev_attr);