Yep. That's also what I was talking about, FWIW. On Mon, Nov 19, 2018 at 11:31 AM, Christian Brauner <christian@xxxxxxxxxx> wrote: > On Mon, Nov 19, 2018 at 01:02:06PM -0600, Eric W. Biederman wrote: >> Christian Brauner <christian@xxxxxxxxxx> writes: >> >> > On Mon, Nov 19, 2018 at 07:59:24AM -0800, Daniel Colascione wrote: >> >> You never addressed my comment on the previous patch about your use of >> > >> > Sorry, that thread exploded so quickly that I might have missed it. >> > >> >> private_data here. Why can't you use the struct pid reference that's >> >> already in the inode? >> > >> > If that's what people prefer we can probably use that. There was >> > precedent for stashing away such data in fs/proc/base.c already for >> > various other things including user namespaces and struct mm so I >> > followed this model. A prior version of my patch (I didn't send out) did >> > retrive the inode via proc_pid() in .open() took an additional reference >> > via get_pid() and dropped it in .release(). Do we prefer that? >> >> If you are using proc/<pid>/ directories as your file descriptors, you >> don't need to add an open or a release method at all. The existing file >> descriptors hold a reference to the inode which holds a reference the >> the struct pid. >> >> The only time you need to get a reference is when you need a task >> and kill_pid_info already performs that work for you. > > Oh, I see what you and Andy are saying now. Sweet, that means we can > trim down the patch even more. Less code, less headache. > > Thanks! > >> >> So using proc_pid is all you need to do to get the pid from the existing >> file descriptors. >> >> Eric >>
