[PATCH v2 05/18] mm/gup: introduce pin_user_pages*() and FOLL_PIN

[Ira Weiny]

> 
> 
> ...
> >> +This document describes the following functions: ::
> >> +
> >> + pin_user_pages
> >> + pin_user_pages_fast
> >> + pin_user_pages_remote
> >> +
> >> + pin_longterm_pages
> >> + pin_longterm_pages_fast
> >> + pin_longterm_pages_remote
> >> +
> >> +Basic description of FOLL_PIN
> >> +=============================
> >> +
> >> +A new flag for get_user_pages ("gup") has been added: FOLL_PIN. FOLL_PIN has
> > 
> > Consider reading this after, say, half a year ;-)
> > 
> 
> OK, OK. I knew when I wrote that that it was not going to stay new forever, but
> somehow failed to write the right thing anyway. :) 
> 
> Here's a revised set of paragraphs:
> 
> Basic description of FOLL_PIN
> =============================
> 
> FOLL_PIN and FOLL_LONGTERM are flags that can be passed to the get_user_pages*()
> ("gup") family of functions. FOLL_PIN has significant interactions and
> interdependencies with FOLL_LONGTERM, so both are covered here.
> 
> Both FOLL_PIN and FOLL_LONGTERM are internal to gup, meaning that neither
> FOLL_PIN nor FOLL_LONGTERM should not appear at the gup call sites. This allows
> the associated wrapper functions  (pin_user_pages() and others) to set the
> correct combination of these flags, and to check for problems as well.

I like this revision as well.

Ira