consistent treatment of EFAULT on O_DIRECT read/write

Make local filesystems treat a fault as shortened IO,
returning -EFAULT only if nothing had been transferred.
That's how everything else (NFS, FUSE, ceph, Lustre)
behaves.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2016-10-03 20:38:55 -04:00
parent 08895a8b6b
commit 4038acdb18

View File

@ -246,6 +246,9 @@ static ssize_t dio_complete(struct dio *dio, ssize_t ret, bool is_async)
if ((dio->op == REQ_OP_READ) &&
((offset + transferred) > dio->i_size))
transferred = dio->i_size - offset;
/* ignore EFAULT if some IO has been done */
if (unlikely(ret == -EFAULT) && transferred)
ret = 0;
}
if (ret == 0)