[PATCH] net: make socket read/write_iter() honor IOCB_NOWAIT
From: Jens Axboe <axboe@kernel.dk>
Date: 2019-12-10 04:06:35
Subsystem:
networking [general], networking [sockets], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Willem de Bruijn, Linus Torvalds
The socket read/write helpers only look at the file O_NONBLOCK. not the iocb IOCB_NOWAIT flag. This breaks users like preadv2/pwritev2 and io_uring that rely on not having the file itself marked nonblocking, but rather the iocb itself. Signed-off-by: Jens Axboe <axboe@kernel.dk> --- This seems like a gross oversight? Verified that it's broken, and verified that it works for me with this check added.
diff --git a/net/socket.c b/net/socket.c
index b343db1489bd..b116e58d6438 100644
--- a/net/socket.c
+++ b/net/socket.c@@ -957,7 +957,7 @@ static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to) .msg_iocb = iocb}; ssize_t res; - if (file->f_flags & O_NONBLOCK) + if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT)) msg.msg_flags = MSG_DONTWAIT; if (iocb->ki_pos != 0)
@@ -982,7 +982,7 @@ static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from) if (iocb->ki_pos != 0) return -ESPIPE; - if (file->f_flags & O_NONBLOCK) + if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT)) msg.msg_flags = MSG_DONTWAIT; if (sock->type == SOCK_SEQPACKET)
--
Jens Axboe