On Thu, Jul 24, 2014 at 11:31:05AM +0200, David Herrmann wrote: > Hi > > On Wed, Jul 23, 2014 at 9:25 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: > > On Wed, Jul 23, 2014 at 05:26:38PM +0200, David Herrmann wrote: > >> Lets order things correctly: > >> ->load() > >> ->fistopen() > >> ->open() > >> ->close() > >> ->lastclose() > >> ->unload() > >> > >> This doesn't change much as only savage and radeon use ->firstopen() and > >> they just do map-initialization. Therefore, the global drm mutex makes > >> sure there cannot be any other f_op between ->open() and ->firstopen(). > >> However, once we get rid of that lock, we really want ->firstopen() to > >> initialize the device before ->open() is called. > >> > >> Furthermore, this fixes the clean-up path in drm_open(). We currently > >> don't cleanup the drm_file object if ->firstopen() fails. > >> > >> Signed-off-by: David Herrmann <dh.herrmann@xxxxxxxxx> > >> --- > >> drivers/gpu/drm/drm_fops.c | 139 +++++++++++++++++++++------------------------ > >> include/drm/drmP.h | 2 +- > >> 2 files changed, 66 insertions(+), 75 deletions(-) > >> > >> diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c > >> index 021fe5d..8e73519 100644 > >> --- a/drivers/gpu/drm/drm_fops.c > >> +++ b/drivers/gpu/drm/drm_fops.c > >> @@ -45,7 +45,7 @@ EXPORT_SYMBOL(drm_global_mutex); > >> > >> static int drm_open_helper(struct file *filp, struct drm_minor *minor); > >> > >> -static int drm_setup(struct drm_device * dev) > >> +static int drm_firstopen(struct drm_device * dev) > > > > All the stuff in here is only for legacy drivers. Imo we should rename > > this to drm_legacy_setup and hide it harder. > > > > Also touching the init ordering for ums drivers is a bit risky, I'd advise > > against it. firstopen is officially dead for kms driver and really there's > > nothing legit you can do in there. imx abused until they've switched over > > to the component framework. > > > > I'd just drop this one tbh. > > I did a driver audit when writing this patch, there're only 2 drivers > using firstopen: > > * radeon_cp: sets two fields of dev_private and calls drm_addmap() on > those. In lastclose(), it calls drm_rmmap() > * savage: sets several fields in dev_private, calls > arch_phys_wc_add() for some regions and requests a drm-map for those > via drm_addmap(). On lastclose(), it reverts exactly those steps. > > Taking into account that firstopen() just runs with drm_device > context, not with drm_file context, I really think we should be > calling it _before_ doing ->open(). I even think the drivers would > fail horribly if we don't do this patch and some other user-context > sneaks in between both calls (currently impossible thanks to > drm_global_mutex). > > Both ->firstopen() callbacks are fairly trivial. In favor of making > the error-paths work in drm_open() I'd really like to get this in. > This patch is preparing for my drm_file rework that can make > drm_dev_unregister() stop all open files immediately. > > But I honestly don't care much for UMS drivers, so if you NACK this, > I'd just ignore the error code and add a comment that we don't do > error-handling for UMS. Yeah, I prefer just labels for dragons instead of poking them ;-) -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
