[PATCH 3/3] io_uring: don't re-calculate iov_iter nr_segs in io_import_kbuf()

[Ming Lei <ming.lei@redhat.com>]

We have provide correct byte counts to iov_iter, and it is enough to
cap the iteration, not necessary to re-calculate exact nr_segs.

Especially the previous two patches avoid to use bio->bi_vcnt as
split hint, and don't use iov_iter->nr_segs to initialize bio->bi_vcnt.

The iov_iter nr_segs re-calculation[1] is added for avoiding unnecessary
bio split, which is fixed now by the previous two patches.

[1] https://lkml.org/lkml/2025/4/16/351

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 io_uring/rsrc.c | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index a63474b331bf..ee6283676ba7 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -1055,16 +1055,6 @@ static int io_import_kbuf(int ddir, struct iov_iter *iter,
 
 	iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, count);
 	iov_iter_advance(iter, offset);
-
-	if (count < imu->len) {
-		const struct bio_vec *bvec = iter->bvec;
-
-		while (len > bvec->bv_len) {
-			len -= bvec->bv_len;
-			bvec++;
-		}
-		iter->nr_segs = 1 + bvec - iter->bvec;
-	}
 	return 0;
 }
 
-- 
2.47.0