[PATCH AUTOSEL 4.20 56/77] hv_netvsc: Refactor assignments of struct netvsc_device_info

Sasha Levin
2019-02-15T02:38:09Z

From: Haiyang Zhang <haiyangz@microsoft.com>

[ Upstream commit 7c9f335a3ff20557a92584199f3d35c7e992bbe5 ]

These assignments occur in multiple places. The patch refactor them
to a function for simplicity. It also puts the struct to heap area
for future expension.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
[sl: fix up subject line]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/hyperv/netvsc_drv.c | 134 ++++++++++++++++++++------------
1 file changed, 85 insertions(+), 49 deletions(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index cf36e7ff3191..4055e12fce9a 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -857,6 +857,36 @@ static void netvsc_get_channels(struct net_device *net,
}
}

+/* Alloc struct netvsc_device_info, and initialize it from either existing
+ * struct netvsc_device, or from default values.
+ */
+static struct netvsc_device_info *netvsc_devinfo_get
+ (struct netvsc_device *nvdev)
+{
+ struct netvsc_device_info *dev_info;
+
+ dev_info = kzalloc(sizeof(*dev_info), GFP_ATOMIC);
+
+ if (!dev_info)
+ return NULL;
+
+ if (nvdev) {
+ dev_info->num_chn = nvdev->num_chn;
+ dev_info->send_sections = nvdev->send_section_cnt;
+ dev_info->send_section_size = nvdev->send_section_size;
+ dev_info->recv_sections = nvdev->recv_section_cnt;
+ dev_info->recv_section_size = nvdev->recv_section_size;
+ } else {
+ dev_info->num_chn = VRSS_CHANNEL_DEFAULT;
+ dev_info->send_sections = NETVSC_DEFAULT_TX;
+ dev_info->send_section_size = NETVSC_SEND_SECTION_SIZE;
+ dev_info->recv_sections = NETVSC_DEFAULT_RX;
+ dev_info->recv_section_size = NETVSC_RECV_SECTION_SIZE;
+ }
+
+ return dev_info;
+}
+
static int netvsc_detach(struct net_device *ndev,
struct netvsc_device *nvdev)
{
@@ -942,7 +972,7 @@ static int netvsc_set_channels(struct net_device *net,
struct net_device_context *net_device_ctx = netdev_priv(net);
struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
unsigned int orig, count = channels->combined_count;
- struct netvsc_device_info device_info;
+ struct netvsc_device_info *device_info;
int ret;

/* We do not support separate count for rx, tx, or other */
@@ -961,24 +991,26 @@ static int netvsc_set_channels(struct net_device *net,

orig = nvdev->num_chn;

- memset(&device_info, 0, sizeof(device_info));
- device_info.num_chn = count;
- device_info.send_sections = nvdev->send_section_cnt;
- device_info.send_section_size = nvdev->send_section_size;
- device_info.recv_sections = nvdev->recv_section_cnt;
- device_info.recv_section_size = nvdev->recv_section_size;
+ device_info = netvsc_devinfo_get(nvdev);
+
+ if (!device_info)
+ return -ENOMEM;
+
+ device_info->num_chn = count;

ret = netvsc_detach(net, nvdev);
if (ret)
- return ret;
+ goto out;

- ret = netvsc_attach(net, &device_info);
+ ret = netvsc_attach(net, device_info);
if (ret) {
- device_info.num_chn = orig;
- if (netvsc_attach(net, &device_info))
+ device_info->num_chn = orig;
+ if (netvsc_attach(net, device_info))
netdev_err(net, "restoring channel setting failed\n");
}

+out:
+ kfree(device_info);
return ret;
}

@@ -1047,48 +1079,45 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
int orig_mtu = ndev->mtu;
- struct netvsc_device_info device_info;
+ struct netvsc_device_info *device_info;
int ret = 0;

if (!nvdev || nvdev->destroy)
return -ENODEV;

+ device_info = netvsc_devinfo_get(nvdev);
+
+ if (!device_info)
+ return -ENOMEM;
+
/* Change MTU of underlying VF netdev first. */
if (vf_netdev) {
ret = dev_set_mtu(vf_netdev, mtu);
if (ret)
- return ret;
+ goto out;
}

- memset(&device_info, 0, sizeof(device_info));
- device_info.num_chn = nvdev->num_chn;
- device_info.send_sections = nvdev->send_section_cnt;
- device_info.send_section_size = nvdev->send_section_size;
- device_info.recv_sections = nvdev->recv_section_cnt;
- device_info.recv_section_size = nvdev->recv_section_size;
-
ret = netvsc_detach(ndev, nvdev);
if (ret)
goto rollback_vf;

ndev->mtu = mtu;

- ret = netvsc_attach(ndev, &device_info);
- if (ret)
- goto rollback;
-
- return 0;
+ ret = netvsc_attach(ndev, device_info);
+ if (!ret)
+ goto out;

-rollback:
/* Attempt rollback to original MTU */
ndev->mtu = orig_mtu;

- if (netvsc_attach(ndev, &device_info))
+ if (netvsc_attach(ndev, device_info))
netdev_err(ndev, "restoring mtu failed\n");
rollback_vf:
if (vf_netdev)
dev_set_mtu(vf_netdev, orig_mtu);

+out:
+ kfree(device_info);
return ret;
}

@@ -1673,7 +1702,7 @@ static int netvsc_set_ringparam(struct net_device *ndev,
{
struct net_device_context *ndevctx = netdev_priv(ndev);
struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
- struct netvsc_device_info device_info;
+ struct netvsc_device_info *device_info;
struct ethtool_ringparam orig;
u32 new_tx, new_rx;
int ret = 0;
@@ -1693,26 +1722,29 @@ static int netvsc_set_ringparam(struct net_device *ndev,
new_rx == orig.rx_pending)
return 0; /* no change */

- memset(&device_info, 0, sizeof(device_info));
- device_info.num_chn = nvdev->num_chn;
- device_info.send_sections = new_tx;
- device_info.send_section_size = nvdev->send_section_size;
- device_info.recv_sections = new_rx;
- device_info.recv_section_size = nvdev->recv_section_size;
+ device_info = netvsc_devinfo_get(nvdev);
+
+ if (!device_info)
+ return -ENOMEM;
+
+ device_info->send_sections = new_tx;
+ device_info->recv_sections = new_rx;

ret = netvsc_detach(ndev, nvdev);
if (ret)
- return ret;
+ goto out;

- ret = netvsc_attach(ndev, &device_info);
+ ret = netvsc_attach(ndev, device_info);
if (ret) {
- device_info.send_sections = orig.tx_pending;
- device_info.recv_sections = orig.rx_pending;
+ device_info->send_sections = orig.tx_pending;
+ device_info->recv_sections = orig.rx_pending;

- if (netvsc_attach(ndev, &device_info))
+ if (netvsc_attach(ndev, device_info))
netdev_err(ndev, "restoring ringparam failed");
}

+out:
+ kfree(device_info);
return ret;
}

@@ -2166,7 +2198,7 @@ static int netvsc_probe(struct hv_device *dev,
{
struct net_device *net = NULL;
struct net_device_context *net_device_ctx;
- struct netvsc_device_info device_info;
+ struct netvsc_device_info *device_info = NULL;
struct netvsc_device *nvdev;
int ret = -ENOMEM;

@@ -2213,21 +2245,21 @@ static int netvsc_probe(struct hv_device *dev,
netif_set_real_num_rx_queues(net, 1);

/* Notify the netvsc driver of the new device */
- memset(&device_info, 0, sizeof(device_info));
- device_info.num_chn = VRSS_CHANNEL_DEFAULT;
- device_info.send_sections = NETVSC_DEFAULT_TX;
- device_info.send_section_size = NETVSC_SEND_SECTION_SIZE;
- device_info.recv_sections = NETVSC_DEFAULT_RX;
- device_info.recv_section_size = NETVSC_RECV_SECTION_SIZE;
-
- nvdev = rndis_filter_device_add(dev, &device_info);
+ device_info = netvsc_devinfo_get(NULL);
+
+ if (!device_info) {
+ ret = -ENOMEM;
+ goto devinfo_failed;
+ }
+
+ nvdev = rndis_filter_device_add(dev, device_info);
if (IS_ERR(nvdev)) {
ret = PTR_ERR(nvdev);
netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
goto rndis_failed;
}

- memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
+ memcpy(net->dev_addr, device_info->mac_adr, ETH_ALEN);

/* We must get rtnl lock before scheduling nvdev->subchan_work,
* otherwise netvsc_subchan_work() can get rtnl lock first and wait
@@ -2265,12 +2297,16 @@ static int netvsc_probe(struct hv_device *dev,

list_add(&net_device_ctx->list, &netvsc_dev_list);
rtnl_unlock();
+
+ kfree(device_info);
return 0;

register_failed:
rtnl_unlock();
rndis_filter_device_remove(dev, nvdev);
rndis_failed:
+ kfree(device_info);
+devinfo_failed:
free_percpu(net_device_ctx->vf_stats);
no_stats:
hv_set_drvdata(dev, NULL);
--
2.19.1