switch AF_PACKET and AF_UNIX to skb_copy_datagram_from_iter()

... and kill skb_copy_datagram_iovec()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

4 files changed, 18 insertions, 95 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 178cdbde82f0..7691ad5b4771 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2656,9 +2656,6 @@ static inline int skb_copy_and_csum_datagram_msg(struct sk_buff *skb, int hlen,
 {
         return skb_copy_and_csum_datagram_iovec(skb, hlen, msg->msg_iov);
 }
-int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset,
-                                 const struct iovec *from, int from_offset,
-                                 int len);
 int skb_copy_datagram_from_iter(struct sk_buff *skb, int offset,
                                  struct iov_iter *from, int len);
 int skb_copy_datagram_iter(const struct sk_buff *from, int offset,
diff --git a/net/core/datagram.c b/net/core/datagram.c
index c4d832efebb8..b6e303b0f01f 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -480,98 +480,14 @@ short_copy:
 EXPORT_SYMBOL(skb_copy_datagram_iter);
 
 /**
- *      skb_copy_datagram_from_iovec - Copy a datagram from an iovec.
+ *      skb_copy_datagram_from_iter - Copy a datagram from an iov_iter.
  *      @skb: buffer to copy
  *      @offset: offset in the buffer to start copying to
- *      @from: io vector to copy to
- *      @from_offset: offset in the io vector to start copying from
+ *      @from: the copy source
  *      @len: amount of data to copy to buffer from iovec
  *
  *      Returns 0 or -EFAULT.
- *      Note: the iovec is not modified during the copy.
  */
-int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset,
-                                 const struct iovec *from, int from_offset,
-                                 int len)
-{
-        int start = skb_headlen(skb);
-        int i, copy = start - offset;
-        struct sk_buff *frag_iter;
-
-        /* Copy header. */
-        if (copy > 0) {
-                if (copy > len)
-                        copy = len;
-                if (memcpy_fromiovecend(skb->data + offset, from, from_offset,
-                                        copy))
-                        goto fault;
-                if ((len -= copy) == 0)
-                        return 0;
-                offset += copy;
-                from_offset += copy;
-        }
-
-        /* Copy paged appendix. Hmm... why does this look so complicated? */
-        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-                int end;
-                const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-
-                WARN_ON(start > offset + len);
-
-                end = start + skb_frag_size(frag);
-                if ((copy = end - offset) > 0) {
-                        int err;
-                        u8  *vaddr;
-                        struct page *page = skb_frag_page(frag);
-
-                        if (copy > len)
-                                copy = len;
-                        vaddr = kmap(page);
-                        err = memcpy_fromiovecend(vaddr + frag->page_offset +
-                                                  offset - start,
-                                                  from, from_offset, copy);
-                        kunmap(page);
-                        if (err)
-                                goto fault;
-
-                        if (!(len -= copy))
-                                return 0;
-                        offset += copy;
-                        from_offset += copy;
-                }
-                start = end;
-        }
-
-        skb_walk_frags(skb, frag_iter) {
-                int end;
-
-                WARN_ON(start > offset + len);
-
-                end = start + frag_iter->len;
-                if ((copy = end - offset) > 0) {
-                        if (copy > len)
-                                copy = len;
-                        if (skb_copy_datagram_from_iovec(frag_iter,
-                                                         offset - start,
-                                                         from,
-                                                         from_offset,
-                                                         copy))
-                                goto fault;
-                        if ((len -= copy) == 0)
-                                return 0;
-                        offset += copy;
-                        from_offset += copy;
-                }
-                start = end;
-        }
-        if (!len)
-                return 0;
-
-fault:
-        return -EFAULT;
-}
-EXPORT_SYMBOL(skb_copy_datagram_from_iovec);
-
 int skb_copy_datagram_from_iter(struct sk_buff *skb, int offset,
                                  struct iov_iter *from,
                                  int len)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 108d7f381b87..dfb148e9fdaa 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -2408,6 +2408,10 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
         unsigned short gso_type = 0;
         int hlen, tlen;
         int extra_len = 0;
+        struct iov_iter from;
+        ssize_t n;
+
+        iov_iter_init(&from, WRITE, msg->msg_iov, msg->msg_iovlen, len);
 
         /*
          *      Get and verify the address.
@@ -2446,8 +2450,9 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
 
                 len -= vnet_hdr_len;
 
-                err = memcpy_from_msg((void *)&vnet_hdr, msg, vnet_hdr_len);
-                if (err < 0)
+                err = -EFAULT;
+                n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &from);
+                if (n != vnet_hdr_len)
                         goto out_unlock;
 
                 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
@@ -2517,7 +2522,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
         }
 
         /* Returns -EFAULT on error */
-        err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
+        err = skb_copy_datagram_from_iter(skb, offset, &from, len);
         if (err)
                 goto out_free;
 
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 5eee625d113f..4450d6226602 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1459,6 +1459,9 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock,
         struct scm_cookie tmp_scm;
         int max_level;
         int data_len = 0;
+        struct iov_iter from;
+
+        iov_iter_init(&from, WRITE, msg->msg_iov, msg->msg_iovlen, len);
 
         if (NULL == siocb->scm)
                 siocb->scm = &tmp_scm;
@@ -1516,7 +1519,7 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock,
         skb_put(skb, len - data_len);
         skb->data_len = data_len;
         skb->len = len;
-        err = skb_copy_datagram_from_iovec(skb, 0, msg->msg_iov, 0, len);
+        err = skb_copy_datagram_from_iter(skb, 0, &from, len);
         if (err)
                 goto out_free;
 
@@ -1638,6 +1641,9 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
         bool fds_sent = false;
         int max_level;
         int data_len;
+        struct iov_iter from;
+
+        iov_iter_init(&from, WRITE, msg->msg_iov, msg->msg_iovlen, len);
 
         if (NULL == siocb->scm)
                 siocb->scm = &tmp_scm;
@@ -1694,8 +1700,7 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
                 skb_put(skb, size - data_len);
                 skb->data_len = data_len;
                 skb->len = size;
-                err = skb_copy_datagram_from_iovec(skb, 0, msg->msg_iov,
-                                                   sent, size);
+                err = skb_copy_datagram_from_iter(skb, 0, &from, size);
                 if (err) {
                         kfree_skb(skb);
                         goto out_err;