On Thu, Apr 19, 2018 at 07:43:56AM -0700, Matthew Wilcox wrote: > On Thu, Apr 19, 2018 at 10:38:25AM -0400, Jerome Glisse wrote: > > Oh can i get one more small slot for fs ? I want to ask if they are > > any people against having a callback everytime a struct file is added > > to a task_struct and also having a secondary array so that special > > file like device file can store something opaque per task_struct per > > struct file. > > Do you really want something per _thread_, and not per _mm_? Well per mm would be fine but i do not see how to make that happen with reasonable structure. So issue is that you can have multiple task with same mm but different file descriptors (or am i wrong here ?) thus there would be no easy way given a struct file to lookup the per mm struct. So as a not perfect solution i see a new array in filedes which would allow device driver to store a pointer to their per mm data structure. To be fair usualy you will only have a single fd in a single task for a given device. If you see an easy way to get a per mm per inode pointer store somewhere with easy lookup i am all ears :) Cheers, Jérôme
