From cbbd26b8b1a6af9c02e2b6523e12bd50cc765059 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 1 Nov 2016 22:09:04 -0400 Subject: [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: Al Viro --- drivers/bluetooth/hci_vhci.c | 2 +- drivers/net/macvtap.c | 4 +--- drivers/net/tun.c | 7 ++----- drivers/usb/gadget/function/f_fs.c | 2 +- drivers/usb/gadget/legacy/inode.c | 2 +- drivers/vhost/scsi.c | 3 +-- drivers/vhost/vhost.c | 3 +-- 7 files changed, 8 insertions(+), 15 deletions(-) (limited to 'drivers') diff --git a/drivers/bluetooth/hci_vhci.c b/drivers/bluetooth/hci_vhci.c index c4a75a18dcae..233e850fdac7 100644 --- a/drivers/bluetooth/hci_vhci.c +++ b/drivers/bluetooth/hci_vhci.c @@ -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; } diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 070e3290aa6e..19d81ca3fb49 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -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) && diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 8093e39ae263..4fa2d756548a 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -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) && diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 17989b72cdae..0bfd1e25b431 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -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; } diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c index bd82dd12deff..10b2576f8b6a 100644 --- a/drivers/usb/gadget/legacy/inode.c +++ b/drivers/usb/gadget/legacy/inode.c @@ -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; } diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 6e29d053843d..b296985fda0d 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -922,8 +922,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) */ iov_iter_init(&out_iter, WRITE, vq->iov, out, out_size); - ret = copy_from_iter(req, req_size, &out_iter); - if (unlikely(ret != req_size)) { + if (unlikely(!copy_from_iter_full(req, req_size, &out_iter))) { vq_err(vq, "Faulted on copy_from_iter\n"); vhost_scsi_send_bad_target(vs, vq, head, out); continue; diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index c6f2d89c0e97..06e8b81b6253 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1862,8 +1862,7 @@ static int get_indirect(struct vhost_virtqueue *vq, i, count); return -EINVAL; } - if (unlikely(copy_from_iter(&desc, sizeof(desc), &from) != - sizeof(desc))) { + if (unlikely(!copy_from_iter_full(&desc, sizeof(desc), &from))) { vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n", i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc); return -EINVAL; -- cgit v1.2.3