From: Bobby Eshleman <[email protected]>
Add a net pointer, netns_tracker, and net_mode to the vsock skb and
helpers for getting/setting them. These fields are only used by
vsock_loopback in order to avoid net-related race conditions (more info
in the loopback patch).
This extends virtio_vsock_skb_cb to 32 bytes (with
CONFIG_NET_DEV_REFCNT_TRACKER=y):
struct virtio_vsock_skb_cb {
struct net * net; /* 0 8 */
netns_tracker ns_tracker; /* 8 8 */
enum vsock_net_mode net_mode; /* 16 4 */
u32 offset; /* 20 4 */
bool reply; /* 24 1 */
bool tap_delivered; /* 25 1 */
/* size: 32, cachelines: 1, members: 6 */
/* padding: 6 */
/* last cacheline: 32 bytes */
};
Signed-off-by: Bobby Eshleman <[email protected]>
---
Changes in v9:
- update commit message to specify usage by loopback only
- add comment in virtio_vsock_skb_cb mentioning usage by vsock_loopback
- add ns_tracker to skb->cb
- removed Stefano's Reviewed-by trailer due to ns_tracker addition (not
sure if this is the right process thing to do)
Changes in v7:
- rename `orig_net_mode` to `net_mode`
- update commit message with a more complete explanation of changes
Changes in v5:
- some diff context change due to rebase to current net-next
---
include/linux/virtio_vsock.h | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
index 18deb3c8dab3..a3ef752cdb95 100644
--- a/include/linux/virtio_vsock.h
+++ b/include/linux/virtio_vsock.h
@@ -10,6 +10,10 @@
#define VIRTIO_VSOCK_SKB_HEADROOM (sizeof(struct virtio_vsock_hdr))
struct virtio_vsock_skb_cb {
+ /* net, net_mode, and ns_tracker are only used by vsock_loopback. */
+ struct net *net;
+ netns_tracker ns_tracker;
+ enum vsock_net_mode net_mode;
u32 offset;
bool reply;
bool tap_delivered;
@@ -130,6 +134,35 @@ static inline size_t virtio_vsock_skb_len(struct sk_buff
*skb)
return (size_t)(skb_end_pointer(skb) - skb->head);
}
+static inline struct net *virtio_vsock_skb_net(struct sk_buff *skb)
+{
+ return VIRTIO_VSOCK_SKB_CB(skb)->net;
+}
+
+static inline void virtio_vsock_skb_set_net(struct sk_buff *skb, struct net
*net)
+{
+ get_net_track(net, &VIRTIO_VSOCK_SKB_CB(skb)->ns_tracker, GFP_KERNEL);
+ VIRTIO_VSOCK_SKB_CB(skb)->net = net;
+}
+
+static inline void virtio_vsock_skb_clear_net(struct sk_buff *skb)
+{
+ put_net_track(VIRTIO_VSOCK_SKB_CB(skb)->net,
+ &VIRTIO_VSOCK_SKB_CB(skb)->ns_tracker);
+ VIRTIO_VSOCK_SKB_CB(skb)->net = NULL;
+}
+
+static inline enum vsock_net_mode virtio_vsock_skb_net_mode(struct sk_buff
*skb)
+{
+ return VIRTIO_VSOCK_SKB_CB(skb)->net_mode;
+}
+
+static inline void virtio_vsock_skb_set_net_mode(struct sk_buff *skb,
+ enum vsock_net_mode
net_mode)
+{
+ VIRTIO_VSOCK_SKB_CB(skb)->net_mode = net_mode;
+}
+
/* Dimension the RX SKB so that the entire thing fits exactly into
* a single 4KiB page. This avoids wasting memory due to alloc_skb()
* rounding up to the next page order and also means that we
--
2.47.3
