staging: comedi: comedi.h: remove __user tag from chanlist

The 'chanlist' is passed to the kernel from user space with the
COMEDI_CMD and COMEDI_CMDTEST ioctls. The do_cmd_ioctl() and
do_cmdtest_ioctl() functions in comedi_fops.c copy this data
to/from user space to kernel space correctly.

Unfortunately, this data is copied back into a struct comedi_cmd
so when the cmd is passed down to the drivers they still see the
pointer as __user data. This results is a number of sparse errors
such as:

  warning: dereference of noderef expression

  warning: incorrect type in argument 2 (different address spaces)
     expected void const *<noident>
     got unsigned int [noderef] <asn:1>*chanlist

  warning: incorrect type in argument 3 (different address spaces)
     expected unsigned int *chanlist
     got unsigned int [noderef] <asn:1>*chanlist

  warning: incorrect type in assignment (different address spaces)
     expected unsigned int *ai_chanlist
     got unsigned int [noderef] <asn:1>*chanlist

The two functions in comedi_fops are the only ones that need the
__user tag. Remove the tag so that all the drivers see the chanlist
pointer in the correct address space.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Acked-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/comedi.h b/drivers/staging/comedi/comedi.h
index 76cdb2c..133f013 100644 (file)
--- a/drivers/staging/comedi/comedi.h
+++ b/drivers/staging/comedi/comedi.h
@@ -365,7 +365,7 @@ struct comedi_cmd {
        unsigned int stop_src;
        unsigned int stop_arg;
 
-       unsigned int __user *chanlist;  /* channel/range list */
+       unsigned int *chanlist; /* channel/range list */
        unsigned int chanlist_len;
 
        short __user *data; /* data list, size depends on subd flags */