xen_console: support the new extended xenstore protocol

Since CS 21994 on xen-unstable.hg and CS
466608f3a32e1f9808acdf832a5843af37e5fcec on qemu-xen-unstable.git, few
changes have been introduced to the PV console xenstore protocol, as
described by the document docs/misc/console.txt under xen-unstable.hg.

From the Qemu point of view, very few modifications are needed to
correctly support the protocol: read from xenstore the "output" node
that tell us what the output of the PV console is going to be.
In case the output is a tty, write to xenstore the device name.

Changes in v2:

- fix error paths: free malloc'ed strings and close the xenstore
connection before returning;

- remove useless snprintf in xenstore_store_pv_console_info if i == 0.

Changes in v3:

- replace xs_daemon_open/xs_daemon_close with xs_open/xs_close.

Changes in v4:

- add a compatibility implementation of xs_open/xs_close.

Changes in v5:

- fix code style.

[agraf] fix build error due to missing stub

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 12 insertions, 0 deletions

diff --git a/hw/xen_common.h b/hw/xen_common.h
index 2c79af64d0..0409ac7971 100644
--- a/hw/xen_common.h
+++ b/hw/xen_common.h
@@ -85,6 +85,18 @@ static inline int xc_domain_add_to_physmap(int xc_handle, uint32_t domid,
     return xc_memory_op(xc_handle, XENMEM_add_to_physmap, &xatp);
 }
 
+static inline struct xs_handle *xs_open(unsigned long flags)
+{
+    return xs_daemon_open();
+}
+
+static inline void xs_close(struct xs_handle *xsh)
+{
+    if (xsh != NULL) {
+        xs_daemon_close(xsh);
+    }
+}
+
 
 /* Xen 4.1 */
 #else