block: fix mismerge in bvec_advance

When Jens merged my commit to only allow contiguous page structs in a
bio_vec with Ming's 5.1 fix to ensue the bvec length didn't overflow
we failed to keep the removal of the expensive nth_page calls.  This
commits adds them back as intended.

Fixes: 5c61ee2cd5 ("Merge tag 'v5.1-rc6' into for-5.2/block")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2019-05-07 08:53:35 +02:00 committed by Jens Axboe
parent 662156641b
commit b8753433fc

View File

@ -133,11 +133,6 @@ static inline struct bio_vec *bvec_init_iter_all(struct bvec_iter_all *iter_all)
return &iter_all->bv;
}
static inline struct page *bvec_nth_page(struct page *page, int idx)
{
return idx == 0 ? page : nth_page(page, idx);
}
static inline void bvec_advance(const struct bio_vec *bvec,
struct bvec_iter_all *iter_all)
{
@ -147,8 +142,7 @@ static inline void bvec_advance(const struct bio_vec *bvec,
bv->bv_page++;
bv->bv_offset = 0;
} else {
bv->bv_page = bvec_nth_page(bvec->bv_page, bvec->bv_offset /
PAGE_SIZE);
bv->bv_page = bvec->bv_page + (bvec->bv_offset >> PAGE_SHIFT);
bv->bv_offset = bvec->bv_offset & ~PAGE_MASK;
}
bv->bv_len = min_t(unsigned int, PAGE_SIZE - bv->bv_offset,