{macvtap,tun}_get_user(): switch to iov_iter

[cascardo/linux.git] / drivers / net / macvtap.c

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 8f80045..22b4cf2 100644 (file)
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -640,12 +640,12 @@ static void macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
 
 /* Get packet from user space buffer */
 static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
-                               const struct iovec *iv, unsigned long total_len,
-                               size_t count, int noblock)
+                               struct iov_iter *from, int noblock)
 {
        int good_linear = SKB_MAX_HEAD(NET_IP_ALIGN);
        struct sk_buff *skb;
        struct macvlan_dev *vlan;
+       unsigned long total_len = iov_iter_count(from);
        unsigned long len = total_len;
        int err;
        struct virtio_net_hdr vnet_hdr = { 0 };
@@ -653,6 +653,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
        int copylen = 0;
        bool zerocopy = false;
        size_t linear;
+       ssize_t n;
 
        if (q->flags & IFF_VNET_HDR) {
                vnet_hdr_len = q->vnet_hdr_sz;
@@ -662,10 +663,11 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
                        goto err;
                len -= vnet_hdr_len;
 
-               err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0,
-                                          sizeof(vnet_hdr));
-               if (err < 0)
+               err = -EFAULT;
+               n = copy_from_iter(&vnet_hdr, sizeof(vnet_hdr), from);
+               if (n != sizeof(vnet_hdr))
                        goto err;
+               iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr));
                if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
                     vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
                                                        vnet_hdr.hdr_len)
@@ -680,17 +682,16 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
        if (unlikely(len < ETH_HLEN))
                goto err;
 
-       err = -EMSGSIZE;
-       if (unlikely(count > UIO_MAXIOV))
-               goto err;
-
        if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) {
+               struct iov_iter i;
+
                copylen = vnet_hdr.hdr_len ? vnet_hdr.hdr_len : GOODCOPY_LEN;
                if (copylen > good_linear)
                        copylen = good_linear;
                linear = copylen;
-               if (iov_pages(iv, vnet_hdr_len + copylen, count)
-                   <= MAX_SKB_FRAGS)
+               i = *from;
+               iov_iter_advance(&i, copylen);
+               if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS)
                        zerocopy = true;
        }
 
@@ -708,10 +709,9 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
                goto err;
 
        if (zerocopy)
-               err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count);
+               err = zerocopy_sg_from_iter(skb, from);
        else {
-               err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len,
-                                                  len);
+               err = skb_copy_datagram_from_iter(skb, 0, from, len);
                if (!err && m && m->msg_control) {
                        struct ubuf_info *uarg = m->msg_control;
                        uarg->callback(uarg, false);
@@ -764,16 +764,12 @@ err:
        return err;
 }
 
-static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv,
-                                unsigned long count, loff_t pos)
+static ssize_t macvtap_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
        struct file *file = iocb->ki_filp;
-       ssize_t result = -ENOLINK;
        struct macvtap_queue *q = file->private_data;
 
-       result = macvtap_get_user(q, NULL, iv, iov_length(iv, count), count,
-                                 file->f_flags & O_NONBLOCK);
-       return result;
+       return macvtap_get_user(q, NULL, from, file->f_flags & O_NONBLOCK);
 }
 
 /* Put packet to the user space buffer */
@@ -1081,8 +1077,9 @@ static const struct file_operations macvtap_fops = {
        .open           = macvtap_open,
        .release        = macvtap_release,
        .read           = new_sync_read,
+       .write          = new_sync_write,
        .read_iter      = macvtap_read_iter,
-       .aio_write      = macvtap_aio_write,
+       .write_iter     = macvtap_write_iter,
        .poll           = macvtap_poll,
        .llseek         = no_llseek,
        .unlocked_ioctl = macvtap_ioctl,
@@ -1095,8 +1092,9 @@ static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock,
                           struct msghdr *m, size_t total_len)
 {
        struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
-       return macvtap_get_user(q, m, m->msg_iov, total_len, m->msg_iovlen,
-                           m->msg_flags & MSG_DONTWAIT);
+       struct iov_iter from;
+       iov_iter_init(&from, WRITE, m->msg_iov, m->msg_iovlen, total_len);
+       return macvtap_get_user(q, m, &from, m->msg_flags & MSG_DONTWAIT);
 }
 
 static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock,