Commit cbbd26b8 authored by Al Viro's avatar Al Viro
Browse files

[iov_iter] new primitives - copy_from_iter_full() and friends 



copy_from_iter_full(), copy_from_iter_full_nocache() and
csum_and_copy_from_iter_full() - counterparts of copy_from_iter()
et.al., advancing iterator only in case of successful full copy
and returning whether it had been successful or not.

Convert some obvious users.  *NOTE* - do not blindly assume that
something is a good candidate for those unless you are sure that
not advancing iov_iter in failure case is the right thing in
this case.  Anything that does short read/short write kind of
stuff (or is in a loop, etc.) is unlikely to be a good one.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent e5517c2a

drivers/bluetooth/hci_vhci.c

+1 −1
Original line number Diff line number Diff line
@@ -181,7 +181,7 @@ static inline ssize_t vhci_get_user(struct vhci_data *data, 
	if (!skb)

		return -ENOMEM;



	if (copy_from_iter(skb_put(skb, len), len, from) != len) {

	if (!copy_from_iter_full(skb_put(skb, len), len, from)) {

		kfree_skb(skb);

		return -EFAULT;

	}

drivers/net/macvtap.c

+1 −3
Original line number Diff line number Diff line
@@ -673,7 +673,6 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, 
	int depth;

	bool zerocopy = false;

	size_t linear;

	ssize_t n;



	if (q->flags & IFF_VNET_HDR) {

		vnet_hdr_len = q->vnet_hdr_sz;
@@ -684,8 +683,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, 
		len -= vnet_hdr_len;



		err = -EFAULT;

		n = copy_from_iter(&vnet_hdr, sizeof(vnet_hdr), from);

		if (n != sizeof(vnet_hdr))

		if (!copy_from_iter_full(&vnet_hdr, sizeof(vnet_hdr), from))

			goto err;

		iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr));

		if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&

drivers/net/tun.c

+2 −5
Original line number Diff line number Diff line
@@ -1171,7 +1171,6 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, 
	bool zerocopy = false;

	int err;

	u32 rxhash;

	ssize_t n;



	if (!(tun->dev->flags & IFF_UP))

		return -EIO;
@@ -1181,8 +1180,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, 
			return -EINVAL;

		len -= sizeof(pi);



		n = copy_from_iter(&pi, sizeof(pi), from);

		if (n != sizeof(pi))

		if (!copy_from_iter_full(&pi, sizeof(pi), from))

			return -EFAULT;

	}
@@ -1191,8 +1189,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, 
			return -EINVAL;

		len -= tun->vnet_hdr_sz;



		n = copy_from_iter(&gso, sizeof(gso), from);

		if (n != sizeof(gso))

		if (!copy_from_iter_full(&gso, sizeof(gso), from))

			return -EFAULT;



		if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&

drivers/usb/gadget/function/f_fs.c

+1 −1
Original line number Diff line number Diff line
@@ -949,7 +949,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data) 
			goto error_mutex;

		}

		if (!io_data->read &&

		    copy_from_iter(data, data_len, &io_data->data) != data_len) {

		    !copy_from_iter_full(data, data_len, &io_data->data)) {

			ret = -EFAULT;

			goto error_mutex;

		}

drivers/usb/gadget/legacy/inode.c

+1 −1
Original line number Diff line number Diff line
@@ -667,7 +667,7 @@ ep_write_iter(struct kiocb *iocb, struct iov_iter *from) 
		return -ENOMEM;

	}



	if (unlikely(copy_from_iter(buf, len, from) != len)) {

	if (unlikely(!copy_from_iter_full(buf, len, from))) {

		value = -EFAULT;

		goto out;

	}

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