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authorStefano Stabellini <sstabellini@kernel.org>2017-04-05 12:04:00 -0700
committerJuergen Gross <jgross@suse.com>2017-05-02 11:11:43 +0200
commitf66c72bea1293786b9916894019f96bcd729505b (patch)
treed06f34c799eb4ccc1ad50786756922c52b516a6f /net/9p/trans_xen.c
parentf023f18ddf41dda487241d1514075b1136eb8101 (diff)
downloadlinux-f66c72bea1293786b9916894019f96bcd729505b.tar.bz2
xen/9pfs: receive responses
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. CC: groug@kaod.org CC: jgross@suse.com CC: Eric Van Hensbergen <ericvh@gmail.com> CC: Ron Minnich <rminnich@sandia.gov> CC: Latchesar Ionkov <lucho@ionkov.net> CC: v9fs-developer@lists.sourceforge.net Signed-off-by: Stefano Stabellini <stefano@aporeto.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
Diffstat (limited to 'net/9p/trans_xen.c')
-rw-r--r--net/9p/trans_xen.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c
index 28f30f49d5dd..47864245c0d4 100644
--- a/net/9p/trans_xen.c
+++ b/net/9p/trans_xen.c
@@ -189,6 +189,62 @@ again:
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(&h, ring->data.in, sizeof(h),
+ masked_prod, &masked_cons,
+ XEN_9PFS_RING_SIZE);
+
+ 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(req->rc->sdata, ring->data.in, h.size,
+ masked_prod, &masked_cons,
+ XEN_9PFS_RING_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)