On Wed, Jan 21, 2009 at 04:12:23PM +0200, Andriy Gapon wrote: > on 21/01/2009 16:05 Robert Watson said the following: > > > > On Wed, 21 Jan 2009, Andriy Gapon wrote: > > > >> Question 1: I am writing a driver that would use per-open private data > >> (among other features). Do I have to use D_TRACKCLOSE flag in this > >> case? In general I am a little bit confused about when d_close is > >> invoked. Supposing D_TRACKCLOSE is not set and multiple programs > >> concurrently open, use and close a device - when d_close is called - > >> when one program closes its last descriptor tied to the device or when > >> the system-wide last such descriptor is closed? > > > > Kostik has already pointed at the cdevpriv API, but just to reiterate > > his point: most people will find the semantics of D_TRACKCLOSE confusing > > and consider them incorrect, so I would advise against using them. > > Robert, Kostik, > > in simplistic layman's terms I need the following - when a particular > program "closes my cdev" (explicitly or via exit) I need to catch that > and de-allocate certain resources. There can be multiple concurrent > programs opening, using and closing my cdev. > > I guess what you both say is that I shouldn't use D_TRACKCLOSE, instead > I should perform the resource management in cdevpriv destructor. > Am I guessing correctly this time?
Yes. This is the purpose of the cdevpriv KPI.
pgpQhazRA1n7T.pgp
Description: PGP signature
