[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 <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2016-11-01 22:09:04 -04:00
parent e5517c2a5a
commit cbbd26b8b1
17 changed files with 121 additions and 39 deletions

View file

@ -630,7 +630,7 @@ int vcc_sendmsg(struct socket *sock, struct msghdr *m, size_t size)
goto out;
skb->dev = NULL; /* for paths shared with net_device interfaces */
ATM_SKB(skb)->atm_options = vcc->atm_options;
if (copy_from_iter(skb_put(skb, size), size, &m->msg_iter) != size) {
if (!copy_from_iter_full(skb_put(skb, size), size, &m->msg_iter)) {
kfree_skb(skb);
error = -EFAULT;
goto out;