From 3318c7add8b43a071498a973548dd24b55c587d4 Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Wed, 18 Nov 2015 17:55:10 +0000 Subject: [PATCH] staging: comedi: simplify returned errors for comedi_write() In order to perform a "write" file operation, an asynchronous COMEDI command in the "write" direction needs to have been set up by the current file object on the COMEDI "write" subdevice associated with the file object. If there is a "write" subdevice, but a command has not been set up by the file object (or is has been set-up in the wrong direction), `comedi_write()` currently returns one of two error values `-EINVAL` or `-EACCES`. `-EACCES` is returned if the command was set up by a different subdevice, or somewhat randomly, if a COMEDI "instruction" is currently being processed. `-EINVAL` is returned in other cases. Simplify it by returning `-EINVAL` for all these cases. Signed-off-by: Ian Abbott Reviewed-by: H Hartley Sweeten Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/comedi_fops.c | 21 +++------------------ 1 file changed, 3 insertions(+), 18 deletions(-) diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index 2a2b5a06ed0e..5a9c9d9782f3 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -2333,15 +2333,7 @@ static ssize_t comedi_write(struct file *file, const char __user *buf, async = s->async; if (!nbytes) goto out; - if (!s->busy) { - retval = -EINVAL; - goto out; - } - if (s->busy != file) { - retval = -EACCES; - goto out; - } - if (!(async->cmd.flags & CMDF_WRITE)) { + if (s->busy != file || !(async->cmd.flags & CMDF_WRITE)) { retval = -EINVAL; goto out; } @@ -2376,15 +2368,8 @@ static ssize_t comedi_write(struct file *file, const char __user *buf, retval = -ERESTARTSYS; break; } - if (!s->busy) { - retval = -EINVAL; - break; - } - if (s->busy != file) { - retval = -EACCES; - break; - } - if (!(async->cmd.flags & CMDF_WRITE)) { + if (s->busy != file || + !(async->cmd.flags & CMDF_WRITE)) { retval = -EINVAL; break; } -- 2.20.1