saner FASYNC handling on file close

[linux-2.6-omap-h63xx.git] / drivers / net / tun.c

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index e6bbc639c2d0c8428cc28e29692760f549bf50ce..33b6d1b122fb59fdadfdd2f156a0596f37efcc25 100644 (file)
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -358,6 +358,66 @@ static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
        return mask;
 }
 
+/* prepad is the amount to reserve at front.  len is length after that.
+ * linear is a hint as to how much to copy (usually headers). */
+static struct sk_buff *tun_alloc_skb(size_t prepad, size_t len, size_t linear,
+                                    gfp_t gfp)
+{
+       struct sk_buff *skb;
+       unsigned int i;
+
+       skb = alloc_skb(prepad + len, gfp|__GFP_NOWARN);
+       if (skb) {
+               skb_reserve(skb, prepad);
+               skb_put(skb, len);
+               return skb;
+       }
+
+       /* Under a page?  Don't bother with paged skb. */
+       if (prepad + len < PAGE_SIZE)
+               return NULL;
+
+       /* Start with a normal skb, and add pages. */
+       skb = alloc_skb(prepad + linear, gfp);
+       if (!skb)
+               return NULL;
+
+       skb_reserve(skb, prepad);
+       skb_put(skb, linear);
+
+       len -= linear;
+
+       for (i = 0; i < MAX_SKB_FRAGS; i++) {
+               skb_frag_t *f = &skb_shinfo(skb)->frags[i];
+
+               f->page = alloc_page(gfp|__GFP_ZERO);
+               if (!f->page)
+                       break;
+
+               f->page_offset = 0;
+               f->size = PAGE_SIZE;
+
+               skb->data_len += PAGE_SIZE;
+               skb->len += PAGE_SIZE;
+               skb->truesize += PAGE_SIZE;
+               skb_shinfo(skb)->nr_frags++;
+
+               if (len < PAGE_SIZE) {
+                       len = 0;
+                       break;
+               }
+               len -= PAGE_SIZE;
+       }
+
+       /* Too large, or alloc fail? */
+       if (unlikely(len)) {
+               kfree_skb(skb);
+               skb = NULL;
+       }
+
+       return skb;
+}
+
 /* Get packet from user space buffer */
 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
 {
@@ -391,14 +451,12 @@ static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv,
                        return -EINVAL;
        }
 
-       if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
+       if (!(skb = tun_alloc_skb(align, len, gso.hdr_len, GFP_KERNEL))) {
                tun->dev->stats.rx_dropped++;
                return -ENOMEM;
        }
 
-       if (align)
-               skb_reserve(skb, align);
-       if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
+       if (skb_copy_datagram_from_iovec(skb, 0, iv, len)) {
                tun->dev->stats.rx_dropped++;
                kfree_skb(skb);
                return -EFAULT;
@@ -748,6 +806,36 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
        return err;
 }
 
+static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr)
+{
+       struct tun_struct *tun = file->private_data;
+
+       if (!tun)
+               return -EBADFD;
+
+       DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
+
+       strcpy(ifr->ifr_name, tun->dev->name);
+
+       ifr->ifr_flags = 0;
+
+       if (ifr->ifr_flags & TUN_TUN_DEV)
+               ifr->ifr_flags |= IFF_TUN;
+       else
+               ifr->ifr_flags |= IFF_TAP;
+
+       if (tun->flags & TUN_NO_PI)
+               ifr->ifr_flags |= IFF_NO_PI;
+
+       if (tun->flags & TUN_ONE_QUEUE)
+               ifr->ifr_flags |= IFF_ONE_QUEUE;
+
+       if (tun->flags & TUN_VNET_HDR)
+               ifr->ifr_flags |= IFF_VNET_HDR;
+
+       return 0;
+}
+
 /* This is like a cut-down ethtool ops, except done via tun fd so no
  * privs required. */
 static int set_offload(struct net_device *dev, unsigned long arg)
@@ -833,6 +921,15 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
        DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
 
        switch (cmd) {
+       case TUNGETIFF:
+               ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr);
+               if (ret)
+                       return ret;
+
+               if (copy_to_user(argp, &ifr, sizeof(ifr)))
+                       return -EFAULT;
+               break;
+
        case TUNSETNOCSUM:
                /* Disable/Enable checksum */
                if (arg)
@@ -973,8 +1070,6 @@ static int tun_chr_close(struct inode *inode, struct file *file)
 
        DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
 
-       tun_chr_fasync(-1, file, 0);
-
        rtnl_lock();
 
        /* Detach from net device */