On Tue, Apr 23, 2019 at 10:28:56AM +0200, Ilya Dryomov wrote:
On Mon, Apr 22, 2019 at 9:44 PM Sasha Levin <sashal@xxxxxxxxxx> wrote:From: Ilya Dryomov <idryomov@xxxxxxxxx> [ Upstream commit 187df76325af5d9e12ae9daec1510307797e54f0 ] A bvec can now consist of multiple physically contiguous pages. This means that bvec_iter_advance() can move to a different page while staying in the same bvec (i.e. ->bi_bvec_done != 0). The messenger works in terms of segments which can now be defined as the smaller of a bvec and a page. The "more bytes to process in this segment" condition holds only if bvec_iter_advance() leaves us in the same bvec _and_ in the same page. On next bvec (possibly in the same page) and on next page (possibly in the same bvec) we may need to set ->last_piece. Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx> Signed-off-by: Sasha Levin (Microsoft) <sashal@xxxxxxxxxx> --- net/ceph/messenger.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 7e71b0df1fbc..3083988ce729 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -840,6 +840,7 @@ static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor, size_t bytes) { struct ceph_bio_iter *it = &cursor->bio_iter; + struct page *page = bio_iter_page(it->bio, it->iter); BUG_ON(bytes > cursor->resid); BUG_ON(bytes > bio_iter_len(it->bio, it->iter)); @@ -851,7 +852,8 @@ static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor, return false; /* no more data */ } - if (!bytes || (it->iter.bi_size && it->iter.bi_bvec_done)) + if (!bytes || (it->iter.bi_size && it->iter.bi_bvec_done && + page == bio_iter_page(it->bio, it->iter))) return false; /* more bytes to process in this segment */ if (!it->iter.bi_size) { @@ -899,6 +901,7 @@ static bool ceph_msg_data_bvecs_advance(struct ceph_msg_data_cursor *cursor, size_t bytes) { struct bio_vec *bvecs = cursor->data->bvec_pos.bvecs; + struct page *page = bvec_iter_page(bvecs, cursor->bvec_iter); BUG_ON(bytes > cursor->resid); BUG_ON(bytes > bvec_iter_len(bvecs, cursor->bvec_iter)); @@ -910,7 +913,8 @@ static bool ceph_msg_data_bvecs_advance(struct ceph_msg_data_cursor *cursor, return false; /* no more data */ } - if (!bytes || cursor->bvec_iter.bi_bvec_done) + if (!bytes || (cursor->bvec_iter.bi_bvec_done && + page == bvec_iter_page(bvecs, cursor->bvec_iter))) return false; /* more bytes to process in this segment */ BUG_ON(cursor->last_piece);Same here, shouldn't be needed.
Dropped, thanks! -- Thanks, Sasha
