Hi On Mon, Jan 20, 2014 at 3:00 AM, Dave Airlie <airlied@xxxxxxxxx> wrote: >>> Hi >>> >>> On Fri, Jan 3, 2014 at 3:41 PM, David Herrmann <dh.herrmann@xxxxxxxxx> wrote: >>>> Hi >>>> >>>> With 3.13-rc1 the required VFS core changes for anonymous backing inodes in DRM >>>> got merged. This series reworks the previous patches (I think from early >>>> August '13) and finally replaces the ugly drm_device->dev_mapping hack. >>>> >>>> The patches should be fairly obvious. As I currently only have nouveau here, I'd >>>> be happy to get some more testers with other drivers. >>>> >>>> Patch #1 adds an internal private mount point to DRM core. >>>> Patch #2 replaces ->dev_mapping with a private anonymous inode for each device. >>>> Patch #3 removes the delayed dev_mapping initialization in TTM. >>>> >>>> The internal mnt-point is based on fs/aio.c and fs/anon_inode.c which do the >>>> same. It's not clear to me why we cannot share the mnt-point between all these, >>>> but Al Viro made clear that he will reject any patches on anon_inode.c which do >>>> that. So lets follow his recommendation and use our own internal mnt-point. >>> Also tested on i915 ivb now (before: nouveau+TTM). I think this is >>> ready for 3.14 if nobody finds any issues. >> > > I talked to Al, > > 7:13 < viro> umm... > 17:14 < viro> you do realize that your module will be impossible to unload? > 17:14 < viro> kern_mount will pin that fs down > 17:14 < viro> bumping module refcount > 17:15 < viro> so kern_unmount() in module_exit is not going to be called at all > 17:15 -!- rafael__ [^rafael@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx] has quit > [Ping timeout: 608 seconds] > 17:16 < viro> what you want is some variation on simple_pin_fs() > 17:17 < viro> done from drm_dev_alloc() > 17:18 < viro> with simple_release_fs() from drm_dev_free(), right after iput() > 17:20 < viro> the export itself is OK (albeit we might be better off > exporting a variant of mount_pseudo() instead, so that aio and > this sucker would both just call mount_dname_pseudo()) > 17:21 < viro> the problem I see there is with kern_mount() use > 17:47 -!- sameo [~samuel@192.55.55.41] has quit [Remote host closed > the connection] > > So maybe we should think about it a bit more :-) So we call simple_pin_fs() in drm_alloc_inode() and add a drm_free_inode() which calls iput() followed by simple_release_fs()? I will write up v3 and test with module re-loading this time. Thanks David _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
