xen: implement support for secondary consoles in the console backend

This patch corresponds to commit
840184a106bc24e745beda5c77e392f6cecd2bc9 from
git://xenbits.xensource.com/qemu-xen-unstable.git.

Signed-off-by: Stefano Stabellini <[email protected]>

diff --git a/hw/xen_console.c b/hw/xen_console.c
index 9426d7374f5864ae3ae8f02847d0508fb758bc8c..134988144b9064448a9661b60f5b1e8af8d0899c 100644 (file)
--- a/hw/xen_console.c
+++ b/hw/xen_console.c
@@ -184,7 +184,11 @@ 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");
@@ -223,10 +227,16 @@ static int con_initialise(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;
 
@@ -255,7 +265,11 @@ 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;
     }
 }
@@ -273,7 +287,7 @@ 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,
     .initialise = con_initialise,
     .event      = con_event,