Messages in this thread | | | From | Ming Lei <> | Date | Tue, 1 Nov 2016 06:46:15 +0800 | Subject | Re: [PATCH 45/60] block: bio: introduce bio_for_each_segment_all_rd() and its write pair |
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On Mon, Oct 31, 2016 at 9:59 PM, Theodore Ts'o <tytso@mit.edu> wrote: > On Sat, Oct 29, 2016 at 04:08:44PM +0800, Ming Lei wrote: >> This patches introduce bio_for_each_segment_all_rd() and >> bio_for_each_segment_all_wt(). >> >> bio_for_each_segment_all_rd() is for replacing >> bio_for_each_segment_all() in case the bvec from bio->bi_io_vec >> is accessed as readonly. >> >> bio_for_each_segment_all_wt() is for replacing >> bio_for_each_segment_all() in case the bvec from bio->bi_io_vec >> need to be updated. > > What is _rd and _wt supposed to stand for? And speaking more
As Christoph replied, _rd means read, which said the bvec pointed by the iterator variable(bvec pointer) is read-only, and the bvec table can't be written into via this usage any more. Maybe bio_for_each_segment_all_ro is better?
On the other hand, _wr meands write, which said the bvec pointed by the iterator variable(bvec pointer) can be written to. Maybe we can use original bio_for_each_segment_all() for it?
> generally, could you write up some more detailed notes about all of > the various new functions they have been added, when they should be > used, and some kind of roadmap about how things are supposed to work > beyond the very high-level description in the introduction in your > patch series? Ideally it would go into the Documentation directory, > so that after this patch set gets applied, people will be able to > refer to it to understand how things are supposed to work.
In the next post, I will add comment on the two helpers, thanks for your review.
Thanks, Ming
> > Thanks!! > > - Ted
-- Ming Lei
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