qemu: implement support for secondary consoles in the console backend

[PATCH 5 of 5] qemu: implement support for secondary
This patch adds support for secondary consoles in the console backend.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[ Patches 1-3 are to xen-unstable but do not have compatibility
  implications, we believe.  Patch 4 is awaiting revision. -iwj ]

diff --git a/hw/xen_console.c b/hw/xen_console.c
index 27f809df6a018f833b8ba6ddee9ea6c63783549a..2cdfb1f944dd65cbdfbc9548fbf554d61326974c 100644 (file)
--- a/hw/xen_console.c
+++ b/hw/xen_console.c
@@ -185,7 +185,10 @@ static int con_init(struct XenDevice *xendev)
 
     /* setup */
     dom = xs_get_domain_path(xenstore, con->xendev.dom);
-    snprintf(con->console, sizeof(con->console), "%s/console", dom);
+    if (!xendev->dev)
+        snprintf(con->console, sizeof(con->console), "%s/console", dom);
+    else
+        snprintf(con->console, sizeof(con->console), "%s/device/console/%d", dom, xendev->dev);
     free(dom);
 
     type = xenstore_read_str(con->console, "type");
@@ -215,10 +218,15 @@ static int con_connect(struct XenDevice *xendev)
     if (xenstore_read_int(con->console, "limit", &limit) == 0)
        con->buffer.max_capacity = limit;
 
-    con->sring = xc_map_foreign_range(xen_xc, con->xendev.dom,
-                                     XC_PAGE_SIZE,
-                                     PROT_READ|PROT_WRITE,
-                                     con->ring_ref);
+    if (!xendev->dev)
+        con->sring = xc_map_foreign_range(xen_xc, con->xendev.dom,
+                                          XC_PAGE_SIZE,
+                                          PROT_READ|PROT_WRITE,
+                                          con->ring_ref);
+    else
+        con->sring = xc_gnttab_map_grant_ref(xendev->gnttabdev, con->xendev.dom,
+                                             con->ring_ref,
+                                             PROT_READ|PROT_WRITE);
     if (!con->sring)
        return -1;
 
@@ -244,7 +252,10 @@ static void con_disconnect(struct XenDevice *xendev)
     xen_be_unbind_evtchn(&con->xendev);
 
     if (con->sring) {
-       munmap(con->sring, XC_PAGE_SIZE);
+        if (!xendev->gnttabdev)
+           munmap(con->sring, XC_PAGE_SIZE);
+        else
+            xc_gnttab_munmap(xendev->gnttabdev, con->sring, 1);
        con->sring = NULL;
     }
 }
@@ -262,9 +273,10 @@ static void con_event(struct XenDevice *xendev)
 
 struct XenDevOps xen_console_ops = {
     .size       = sizeof(struct XenConsole),
-    .flags      = DEVOPS_FLAG_IGNORE_STATE,
+    .flags      = DEVOPS_FLAG_IGNORE_STATE|DEVOPS_FLAG_NEED_GNTDEV,
     .init       = con_init,
     .connect    = con_connect,
     .event      = con_event,
     .disconnect = con_disconnect,
 };
+