We caller this helper if we don't have a read_iter/write_iter available,
and it will go over the iov_iter manually copying data in/out as needed.
But it's currently assuming it's being passed an ITER_IOVEC. Enable
use of ITER_UBUF with this helper as well, in preparation for importing
single segment iovecs as ITER_UBUF.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
fs/read_write.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/fs/read_write.c b/fs/read_write.c
index 7a2ff6157eda..de9ce948d11a 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -748,10 +748,21 @@ static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter,
if (flags & ~RWF_HIPRI)
return -EOPNOTSUPP;
+ if (WARN_ON_ONCE(iter->iter_type != ITER_IOVEC &&
+ iter->iter_type != ITER_UBUF))
+ return -EINVAL;
+
while (iov_iter_count(iter)) {
- struct iovec iovec = iov_iter_iovec(iter);
+ struct iovec iovec;
ssize_t nr;
+ if (iter_is_ubuf(iter)) {
+ iovec.iov_base = iter->ubuf + iter->iov_offset;
+ iovec.iov_len = iov_iter_count(iter);
+ } else {
+ iovec = iov_iter_iovec(iter);
+ }
+
if (type == READ) {
nr = filp->f_op->read(filp, iovec.iov_base,
iovec.iov_len, ppos);
--
2.39.2
