[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>
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 6e29d05..b296985 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -922,8 +922,7 @@
*/
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;