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path: root/drivers/net/tun.c
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Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r--drivers/net/tun.c98
1 files changed, 79 insertions, 19 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 7c8343a4f918..44c4db8450f0 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -69,6 +69,7 @@
#include <net/netns/generic.h>
#include <net/rtnetlink.h>
#include <net/sock.h>
+#include <linux/seq_file.h>
#include <asm/uaccess.h>
@@ -110,7 +111,7 @@ struct tap_filter {
unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
};
-/* DEFAULT_MAX_NUM_RSS_QUEUES were choosed to let the rx/tx queues allocated for
+/* DEFAULT_MAX_NUM_RSS_QUEUES were chosen to let the rx/tx queues allocated for
* the netdevice to be fit in one page. So we can make sure the success of
* memory allocation. TODO: increase the limit. */
#define MAX_TAP_QUEUES DEFAULT_MAX_NUM_RSS_QUEUES
@@ -119,7 +120,7 @@ struct tap_filter {
#define TUN_FLOW_EXPIRE (3 * HZ)
/* A tun_file connects an open character device to a tuntap netdevice. It
- * also contains all socket related strctures (except sock_fprog and tap_filter)
+ * also contains all socket related structures (except sock_fprog and tap_filter)
* to serve as one transmit queue for tuntap device. The sock_fprog and
* tap_filter were kept in tun_struct since they were used for filtering for the
* netdevice not for a specific queue (at least I didn't see the requirement for
@@ -152,6 +153,7 @@ struct tun_flow_entry {
struct tun_struct *tun;
u32 rxhash;
+ u32 rps_rxhash;
int queue_index;
unsigned long updated;
};
@@ -220,6 +222,7 @@ static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun,
rxhash, queue_index);
e->updated = jiffies;
e->rxhash = rxhash;
+ e->rps_rxhash = 0;
e->queue_index = queue_index;
e->tun = tun;
hlist_add_head_rcu(&e->hash_link, head);
@@ -232,6 +235,7 @@ static void tun_flow_delete(struct tun_struct *tun, struct tun_flow_entry *e)
{
tun_debug(KERN_INFO, tun, "delete flow: hash %u index %u\n",
e->rxhash, e->queue_index);
+ sock_rps_reset_flow_hash(e->rps_rxhash);
hlist_del_rcu(&e->hash_link);
kfree_rcu(e, rcu);
--tun->flow_count;
@@ -325,6 +329,7 @@ static void tun_flow_update(struct tun_struct *tun, u32 rxhash,
/* TODO: keep queueing to old queue until it's empty? */
e->queue_index = queue_index;
e->updated = jiffies;
+ sock_rps_record_flow_hash(e->rps_rxhash);
} else {
spin_lock_bh(&tun->lock);
if (!tun_flow_find(head, rxhash) &&
@@ -341,14 +346,27 @@ unlock:
rcu_read_unlock();
}
+/**
+ * Save the hash received in the stack receive path and update the
+ * flow_hash table accordingly.
+ */
+static inline void tun_flow_save_rps_rxhash(struct tun_flow_entry *e, u32 hash)
+{
+ if (unlikely(e->rps_rxhash != hash)) {
+ sock_rps_reset_flow_hash(e->rps_rxhash);
+ e->rps_rxhash = hash;
+ }
+}
+
/* We try to identify a flow through its rxhash first. The reason that
- * we do not check rxq no. is becuase some cards(e.g 82599), chooses
+ * we do not check rxq no. is because some cards(e.g 82599), chooses
* the rxq based on the txq where the last packet of the flow comes. As
* the userspace application move between processors, we may get a
* different rxq no. here. If we could not get rxhash, then we would
* hope the rxq no. may help here.
*/
-static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb)
+static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb,
+ void *accel_priv)
{
struct tun_struct *tun = netdev_priv(dev);
struct tun_flow_entry *e;
@@ -358,12 +376,13 @@ static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb)
rcu_read_lock();
numqueues = ACCESS_ONCE(tun->numqueues);
- txq = skb_get_rxhash(skb);
+ txq = skb_get_hash(skb);
if (txq) {
e = tun_flow_find(&tun->flows[tun_hashfn(txq)], txq);
- if (e)
+ if (e) {
+ tun_flow_save_rps_rxhash(e, txq);
txq = e->queue_index;
- else
+ } else
/* use multiply and shift instead of expensive divide */
txq = ((u64)txq * numqueues) >> 32;
} else if (likely(skb_rx_queue_recorded(skb))) {
@@ -531,7 +550,7 @@ static int tun_attach(struct tun_struct *tun, struct file *file, bool skip_filte
err = 0;
- /* Re-attach the filter to presist device */
+ /* Re-attach the filter to persist device */
if (!skip_filter && (tun->filter_attached == true)) {
err = sk_attach_filter(&tun->fprog, tfile->socket.sk);
if (!err)
@@ -720,14 +739,32 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
struct tun_struct *tun = netdev_priv(dev);
int txq = skb->queue_mapping;
struct tun_file *tfile;
+ u32 numqueues = 0;
rcu_read_lock();
tfile = rcu_dereference(tun->tfiles[txq]);
+ numqueues = ACCESS_ONCE(tun->numqueues);
/* Drop packet if interface is not attached */
- if (txq >= tun->numqueues)
+ if (txq >= numqueues)
goto drop;
+ if (numqueues == 1) {
+ /* Select queue was not called for the skbuff, so we extract the
+ * RPS hash and save it into the flow_table here.
+ */
+ __u32 rxhash;
+
+ rxhash = skb_get_hash(skb);
+ if (rxhash) {
+ struct tun_flow_entry *e;
+ e = tun_flow_find(&tun->flows[tun_hashfn(rxhash)],
+ rxhash);
+ if (e)
+ tun_flow_save_rps_rxhash(e, rxhash);
+ }
+ }
+
tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len);
BUG_ON(!tfile);
@@ -745,8 +782,8 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
/* Limit the number of packets queued by dividing txq length with the
* number of queues.
*/
- if (skb_queue_len(&tfile->socket.sk->sk_receive_queue)
- >= dev->tx_queue_len / tun->numqueues)
+ if (skb_queue_len(&tfile->socket.sk->sk_receive_queue) * numqueues
+ >= dev->tx_queue_len)
goto drop;
if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
@@ -819,9 +856,9 @@ static void tun_poll_controller(struct net_device *dev)
* Tun only receives frames when:
* 1) the char device endpoint gets data from user space
* 2) the tun socket gets a sendmsg call from user space
- * Since both of those are syncronous operations, we are guaranteed
+ * Since both of those are synchronous operations, we are guaranteed
* never to have pending data when we poll for it
- * so theres nothing to do here but return.
+ * so there is nothing to do here but return.
* We need this though so netpoll recognizes us as an interface that
* supports polling, which enables bridge devices in virt setups to
* still use netconsole
@@ -1146,7 +1183,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
skb_reset_network_header(skb);
skb_probe_transport_header(skb, 0);
- rxhash = skb_get_rxhash(skb);
+ rxhash = skb_get_hash(skb);
netif_rx_ni(skb);
tun->dev->stats.rx_packets++;
@@ -1291,8 +1328,7 @@ done:
}
static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
- struct kiocb *iocb, const struct iovec *iv,
- ssize_t len, int noblock)
+ const struct iovec *iv, ssize_t len, int noblock)
{
DECLARE_WAITQUEUE(wait, current);
struct sk_buff *skb;
@@ -1355,7 +1391,7 @@ static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
goto out;
}
- ret = tun_do_read(tun, tfile, iocb, iv, len,
+ ret = tun_do_read(tun, tfile, iv, len,
file->f_flags & O_NONBLOCK);
ret = min_t(ssize_t, ret, len);
if (ret > 0)
@@ -1456,7 +1492,7 @@ static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
SOL_PACKET, TUN_TX_TIMESTAMP);
goto out;
}
- ret = tun_do_read(tun, tfile, iocb, m->msg_iov, total_len,
+ ret = tun_do_read(tun, tfile, m->msg_iov, total_len,
flags & MSG_DONTWAIT);
if (ret > total_len) {
m->msg_flags |= MSG_TRUNC;
@@ -2193,6 +2229,27 @@ static int tun_chr_close(struct inode *inode, struct file *file)
return 0;
}
+#ifdef CONFIG_PROC_FS
+static int tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
+{
+ struct tun_struct *tun;
+ struct ifreq ifr;
+
+ memset(&ifr, 0, sizeof(ifr));
+
+ rtnl_lock();
+ tun = tun_get(f);
+ if (tun)
+ tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
+ rtnl_unlock();
+
+ if (tun)
+ tun_put(tun);
+
+ return seq_printf(m, "iff:\t%s\n", ifr.ifr_name);
+}
+#endif
+
static const struct file_operations tun_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
@@ -2207,7 +2264,10 @@ static const struct file_operations tun_fops = {
#endif
.open = tun_chr_open,
.release = tun_chr_close,
- .fasync = tun_chr_fasync
+ .fasync = tun_chr_fasync,
+#ifdef CONFIG_PROC_FS
+ .show_fdinfo = tun_chr_show_fdinfo,
+#endif
};
static struct miscdevice tun_miscdev = {
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.