Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754705AbdCIAH6 (ORCPT ); Wed, 8 Mar 2017 19:07:58 -0500 Received: from mail.kernel.org ([198.145.29.136]:56400 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753348AbdCIAHv (ORCPT ); Wed, 8 Mar 2017 19:07:51 -0500 From: Stefano Stabellini To: xen-devel@lists.xenproject.org Cc: linux-kernel@vger.kernel.org, sstabellini@kernel.org, Stefano Stabellini , boris.ostrovsky@oracle.com, jgross@suse.com, Eric Van Hensbergen , Ron Minnich , Latchesar Ionkov , v9fs-developer@lists.sourceforge.net Subject: [PATCH v2 6/7] xen/9pfs: receive responses Date: Wed, 8 Mar 2017 15:58:21 -0800 Message-Id: <1489017502-18617-6-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1489017502-18617-1-git-send-email-sstabellini@kernel.org> References: <1489017502-18617-1-git-send-email-sstabellini@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2593 Lines: 85 Upon receiving a notification from the backend, schedule the p9_xen_response work_struct. p9_xen_response checks if any responses are available, if so, it reads them one by one, calling p9_client_cb to send them up to the 9p layer (p9_client_cb completes the request). Handle the ring following the Xen 9pfs specification. Signed-off-by: Stefano Stabellini CC: boris.ostrovsky@oracle.com CC: jgross@suse.com CC: Eric Van Hensbergen CC: Ron Minnich CC: Latchesar Ionkov CC: v9fs-developer@lists.sourceforge.net --- net/9p/trans_xen.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index 0367cbe..4d704aa 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -145,6 +145,61 @@ static int p9_xen_request(struct p9_client *client, struct p9_req_t *p9_req) static void p9_xen_response(struct work_struct *work) { + struct xen_9pfs_front_priv *priv; + struct xen_9pfs_dataring *ring; + RING_IDX cons, prod, masked_cons, masked_prod; + struct xen_9pfs_header h; + struct p9_req_t *req; + int status; + + ring = container_of(work, struct xen_9pfs_dataring, work); + priv = ring->priv; + + while (1) { + cons = ring->intf->in_cons; + prod = ring->intf->in_prod; + virt_rmb(); + + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) { + notify_remote_via_irq(ring->irq); + return; + } + + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE); + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE); + + /* First, read just the header */ + xen_9pfs_read_packet(ring->ring.in, + masked_prod, &masked_cons, + XEN_9PFS_RING_SIZE, &h, sizeof(h)); + + req = p9_tag_lookup(priv->client, h.tag); + if (!req || req->status != REQ_STATUS_SENT) { + dev_warn(&priv->dev->dev, "Wrong req tag=%x\n", h.tag); + cons += h.size; + virt_mb(); + ring->intf->in_cons = cons; + continue; + } + + memcpy(req->rc, &h, sizeof(h)); + req->rc->offset = 0; + + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE); + /* Then, read the whole packet (including the header) */ + xen_9pfs_read_packet(ring->ring.in, + masked_prod, &masked_cons, + XEN_9PFS_RING_SIZE, req->rc->sdata, h.size); + + virt_mb(); + cons += h.size; + ring->intf->in_cons = cons; + + status = (req->status != REQ_STATUS_ERROR) ? + REQ_STATUS_RCVD : REQ_STATUS_ERROR; + + p9_client_cb(priv->client, req, status); + } } static irqreturn_t xen_9pfs_front_event_handler(int irq, void *r) -- 1.9.1