Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

[linux-drm-fsl-dcu.git] / drivers / net / tun.c

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 7cb105c103fe9408eb7c02b96dac4f4bfb702456..3c5a8d8cde5077bc0c2d39d2f0aadc4e7d4a6231 100644 (file)
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -110,7 +110,7 @@ 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 +119,7 @@ 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
@@ -342,7 +342,7 @@ unlock:
 }
 
 /* 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
@@ -531,7 +531,7 @@ 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)
@@ -819,9 +819,9 @@ 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
@@ -981,6 +981,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
        struct sk_buff *skb;
        size_t len = total_len, align = NET_SKB_PAD, linear;
        struct virtio_net_hdr gso = { 0 };
+       int good_linear;
        int offset = 0;
        int copylen;
        bool zerocopy = false;
@@ -1021,12 +1022,16 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
                        return -EINVAL;
        }
 
+       good_linear = SKB_MAX_HEAD(align);
+
        if (msg_control) {
                /* There are 256 bytes to be copied in skb, so there is
                 * enough room for skb expand head in case it is used.
                 * The rest of the buffer is mapped from userspace.
                 */
                copylen = gso.hdr_len ? gso.hdr_len : GOODCOPY_LEN;
+               if (copylen > good_linear)
+                       copylen = good_linear;
                linear = copylen;
                if (iov_pages(iv, offset + copylen, count) <= MAX_SKB_FRAGS)
                        zerocopy = true;
@@ -1034,7 +1039,10 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 
        if (!zerocopy) {
                copylen = len;
-               linear = gso.hdr_len;
+               if (gso.hdr_len > good_linear)
+                       linear = good_linear;
+               else
+                       linear = gso.hdr_len;
        }
 
        skb = tun_alloc_skb(tfile, align, copylen, linear, noblock);
@@ -1281,8 +1289,7 @@ 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;
@@ -1345,9 +1352,11 @@ 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)
+               iocb->ki_pos = ret;
 out:
        tun_put(tun);
        return ret;
@@ -1444,7 +1453,7 @@ 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;