drm/vc4: copy_to_user() returns the number of bytes remaining
authorDan Carpenter <dan.carpenter@oracle.com>
Thu, 17 Dec 2015 12:36:28 +0000 (15:36 +0300)
committerEric Anholt <eric@anholt.net>
Thu, 17 Dec 2015 19:40:11 +0000 (11:40 -0800)
commit65c4777de54a39b2722a4b1ff3306d044014d511
treef0b3cbf05dbb84be80010587d655dfdc32b3d1f0
parent21de54b3c4d08d2b20e80876c6def0b421dfec2e
drm/vc4: copy_to_user() returns the number of bytes remaining

The copy_to/from_user() functions return the number of bytes remaining
to be copied.  We want to return error codes here.

Also it's a bad idea to print an error message if a copy from user fails
because users can use that to spam /var/log/messages which is annoying
so I removed those.

Fixes: 214613656b51 ('drm/vc4: Add an interface for capturing the GPU state after a hang.')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
drivers/gpu/drm/vc4/vc4_gem.c