diff options
author | Stefano Stabellini <sstabellini@kernel.org> | 2017-04-05 12:04:00 -0700 |
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committer | Juergen Gross <jgross@suse.com> | 2017-05-02 11:11:43 +0200 |
commit | f66c72bea1293786b9916894019f96bcd729505b (patch) | |
tree | d06f34c799eb4ccc1ad50786756922c52b516a6f /net/9p/trans_xen.c | |
parent | f023f18ddf41dda487241d1514075b1136eb8101 (diff) | |
download | linux-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.c | 56 |
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) |