[Devel] [PATCH VZ9 15/20] fuse: do not accelerate writes with unknown dirty state

[Alexey Kuznetsov]

If we have no sync seq numbers we cannot force dirty status.
So, route writes via slow path. When CSes reply with dirty seqs,
we will be able to make shortcut.

Signed-off-by: Alexey Kuznetsov <kuznet at acronis.com>
---
 fs/fuse/kio/pcs/pcs_cs_accel.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/fuse/kio/pcs/pcs_cs_accel.c b/fs/fuse/kio/pcs/pcs_cs_accel.c
index 6db4562..d47486d 100644
--- a/fs/fuse/kio/pcs/pcs_cs_accel.c
+++ b/fs/fuse/kio/pcs/pcs_cs_accel.c
@@ -1123,6 +1123,9 @@ struct pcs_int_request * pcs_csa_csl_write_submit(struct pcs_int_request * ireq)
 	ireq_init_acr(ireq);
 
 	for (idx = 0; idx < csl->nsrv; idx++) {
+		/* If dirty status is unknown go to slow path to get a seed */
+		if (csl->cs[idx].sync.dirty_seq == 0)
+			break;
 		if (!csa_cs_submit_write(ireq, idx))
 			break;
 	}
@@ -1171,6 +1174,8 @@ int pcs_csa_csl_write_submit_single(struct pcs_int_request * ireq, int idx)
 {
 	if (idx >= PCS_MAX_ACCEL_CS)
 		return 0;
+	if (ireq->iochunk.csl->cs[idx].sync.dirty_seq == 0)
+		return 0;
 
 	ireq_init_acr(ireq);
 
-- 
1.8.3.1