On Wed, Jun 01, 2022 at 12:23:06PM -0700, Linus Torvalds wrote: > On Wed, Jun 1, 2022 at 12:19 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > > > Why not pass the iocb in ->read and ->write? We're still regretting not > > doing that with file_operations. > > No, all the actual "io" is done by the caller. > > There is no way in hell I want the sysctl callbacks to actually > possibly do user space accesses etc. > > They get a kernel buffer that has already been set up. There is no > iocb or iovec left for them. I wasn't suggesting the iovec. Just the iocb, instead of passing in the ki_filp and the ki_pos. > (That also means that they can take whatever locks they need, > including spinlocks, because there's not going to be any random user > accesses or complex pipe buffer lookups or whatever). > > Linus