}
/**
- * skb_recv_datagram - Receive a datagram skbuff
+ * __skb_recv_datagram - Receive a datagram skbuff
* @sk: socket
* @flags: MSG_ flags
- * @noblock: blocking operation?
+ * @peeked: returns non-zero if this packet has been seen before
* @err: error code returned
*
* Get a datagram skbuff, understands the peeking, nonblocking wakeups
* quite explicitly by POSIX 1003.1g, don't change them without having
* the standard around please.
*/
-struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
- int noblock, int *err)
+struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
+ int *peeked, int *err)
{
struct sk_buff *skb;
long timeo;
if (error)
goto no_packet;
- timeo = sock_rcvtimeo(sk, noblock);
+ timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
do {
/* Again only user level code calls this function, so nothing
* Look at current nfs client by the way...
* However, this function was corrent in any case. 8)
*/
- if (flags & MSG_PEEK) {
- unsigned long cpu_flags;
-
- spin_lock_irqsave(&sk->sk_receive_queue.lock,
- cpu_flags);
- skb = skb_peek(&sk->sk_receive_queue);
- if (skb)
+ unsigned long cpu_flags;
+
+ spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
+ skb = skb_peek(&sk->sk_receive_queue);
+ if (skb) {
+ *peeked = skb->peeked;
+ if (flags & MSG_PEEK) {
+ skb->peeked = 1;
atomic_inc(&skb->users);
- spin_unlock_irqrestore(&sk->sk_receive_queue.lock,
- cpu_flags);
- } else
- skb = skb_dequeue(&sk->sk_receive_queue);
+ } else
+ __skb_unlink(skb, &sk->sk_receive_queue);
+ }
+ spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
if (skb)
return skb;
*err = error;
return NULL;
}
+EXPORT_SYMBOL(__skb_recv_datagram);
+
+struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
+ int noblock, int *err)
+{
+ int peeked;
+
+ return __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
+ &peeked, err);
+}
void skb_free_datagram(struct sock *sk, struct sk_buff *skb)
{
kfree_skb(skb);
+ sk_mem_reclaim(sk);
}
/**
* This function currently only disables BH when acquiring the
* sk_receive_queue lock. Therefore it must not be used in a
* context where that lock is acquired in an IRQ context.
+ *
+ * It returns 0 if the packet was removed by us.
*/
-void skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags)
+int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags)
{
+ int err = 0;
+
if (flags & MSG_PEEK) {
+ err = -ENOENT;
spin_lock_bh(&sk->sk_receive_queue.lock);
if (skb == skb_peek(&sk->sk_receive_queue)) {
__skb_unlink(skb, &sk->sk_receive_queue);
atomic_dec(&skb->users);
+ err = 0;
}
spin_unlock_bh(&sk->sk_receive_queue.lock);
}
kfree_skb(skb);
+ sk_mem_reclaim(sk);
+ return err;
}
EXPORT_SYMBOL(skb_kill_datagram);
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
int end;
- BUG_TRAP(start <= offset + len);
+ WARN_ON(start > offset + len);
end = start + skb_shinfo(skb)->frags[i].size;
if ((copy = end - offset) > 0) {
for (; list; list = list->next) {
int end;
- BUG_TRAP(start <= offset + len);
+ WARN_ON(start > offset + len);
end = start + list->len;
if ((copy = end - offset) > 0) {
return -EFAULT;
}
+/**
+ * skb_copy_datagram_from_iovec - Copy a datagram from an iovec.
+ * @skb: buffer to copy
+ * @offset: offset in the buffer to start copying to
+ * @from: io vector to copy to
+ * @len: amount of data to copy to buffer from iovec
+ *
+ * Returns 0 or -EFAULT.
+ * Note: the iovec is modified during the copy.
+ */
+int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset,
+ struct iovec *from, int len)
+{
+ int start = skb_headlen(skb);
+ int i, copy = start - offset;
+
+ /* Copy header. */
+ if (copy > 0) {
+ if (copy > len)
+ copy = len;
+ if (memcpy_fromiovec(skb->data + offset, from, copy))
+ goto fault;
+ if ((len -= copy) == 0)
+ return 0;
+ offset += copy;
+ }
+
+ /* Copy paged appendix. Hmm... why does this look so complicated? */
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ int end;
+
+ WARN_ON(start > offset + len);
+
+ end = start + skb_shinfo(skb)->frags[i].size;
+ if ((copy = end - offset) > 0) {
+ int err;
+ u8 *vaddr;
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+ struct page *page = frag->page;
+
+ if (copy > len)
+ copy = len;
+ vaddr = kmap(page);
+ err = memcpy_fromiovec(vaddr + frag->page_offset +
+ offset - start, from, copy);
+ kunmap(page);
+ if (err)
+ goto fault;
+
+ if (!(len -= copy))
+ return 0;
+ offset += copy;
+ }
+ start = end;
+ }
+
+ if (skb_shinfo(skb)->frag_list) {
+ struct sk_buff *list = skb_shinfo(skb)->frag_list;
+
+ for (; list; list = list->next) {
+ int end;
+
+ WARN_ON(start > offset + len);
+
+ end = start + list->len;
+ if ((copy = end - offset) > 0) {
+ if (copy > len)
+ copy = len;
+ if (skb_copy_datagram_from_iovec(list,
+ offset - start,
+ from, copy))
+ goto fault;
+ if ((len -= copy) == 0)
+ return 0;
+ offset += copy;
+ }
+ start = end;
+ }
+ }
+ if (!len)
+ return 0;
+
+fault:
+ return -EFAULT;
+}
+EXPORT_SYMBOL(skb_copy_datagram_from_iovec);
+
static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset,
u8 __user *to, int len,
__wsum *csump)
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
int end;
- BUG_TRAP(start <= offset + len);
+ WARN_ON(start > offset + len);
end = start + skb_shinfo(skb)->frags[i].size;
if ((copy = end - offset) > 0) {
for (; list; list=list->next) {
int end;
- BUG_TRAP(start <= offset + len);
+ WARN_ON(start > offset + len);
end = start + list->len;
if ((copy = end - offset) > 0) {
__wsum csum;
int chunk = skb->len - hlen;
+ if (!chunk)
+ return 0;
+
/* Skip filled elements.
* Pretty silly, look at memcpy_toiovec, though 8)
*/
projects / linux-2.6-omap-h63xx.git / blobdiff