2016-10-29 08:12:03

by Ming Lei

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Subject: [PATCH 01/60] block: bio: introduce bio_init_with_vec_table()

Some drivers often uses external bvec table, so introduce
this helper for this case. It is always safe to access the
bio->bi_io_vec in this way for this case.

After converting to this helper, it will becomes a bit easier
to evaluate the remaining direct access to bio->bi_io_vec,
so it can help to prepare for the following multipage bvec
support.

Signed-off-by: Ming Lei <[email protected]>
---
include/linux/bio.h | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 97cb48f03dc7..8634bd24984c 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -664,6 +664,16 @@ static inline void bio_inc_remaining(struct bio *bio)
atomic_inc(&bio->__bi_remaining);
}

+static inline void bio_init_with_vec_table(struct bio *bio,
+ struct bio_vec *table,
+ unsigned max_vecs)
+{
+ bio_init(bio);
+ bio->bi_io_vec = table;
+ bio->bi_max_vecs = max_vecs;
+}
+
+
/*
* bio_set is used to allow other portions of the IO system to
* allocate their own private memory pools for bio and iovec structures.
--
2.7.4


2016-10-29 15:21:13

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH 01/60] block: bio: introduce bio_init_with_vec_table()

Just add the two arguments to bio_init instead of adding a second
function with a way too long name.