[Lguest] [PATCH 4/6] virtio block driver

[Rusty Russell]

On Fri, 2007-09-21 at 14:27 +0200, Jens Axboe wrote:
> On Fri, Sep 21 2007, Rusty Russell wrote:
> > I shall look through the code and see if I can figure out how to fix it.
> > I'm assuming from your response that there's not some strange reason to
> > preserve current behaviour.
> 
> It surely sounds like a bug, if you issue ioctl(fd, CDROMEJECT), the
> driver sees it and returns -ENOTTY, but userland sees a 0 retval. So if
> you have time, please do poke at it a bit.

OK, error (-ENOTTY) gets to blk_end_sync_rq(), but nothing happens to
it.  This patch makes the ioctl return -EIO: I can't see a way to pass
the errno back properly.

diff -r 99e125262d6a block/ll_rw_blk.c
--- a/block/ll_rw_blk.c	Sat Sep 22 15:37:22 2007 +1000
+++ b/block/ll_rw_blk.c	Sun Sep 23 16:43:42 2007 +1000
@@ -2792,6 +2792,9 @@ void blk_end_sync_rq(struct request *rq,
 	rq->end_io_data = NULL;
 	__blk_put_request(rq->q, rq);
 
+	if (error)
+		rq->errors++;
+
 	/*
 	 * complete last, if this is a stack request the process (and thus
 	 * the rq pointer) could be invalid right after this complete()