From 0afb65e74d4ba5b1fae47cd7fef65a6bdc859b57 Mon Sep 17 00:00:00 2001
From: Paul Durrant <paul.durrant@citrix.com>
Date: Thu, 10 Aug 2017 11:38:01 +0100
Subject: [PATCH 2/2] use new interface

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
---
 configure                   |  1 +
 hw/i386/xen/xen-hvm.c       | 62 +++++++++++++++++++++++++++++++++++----------
 include/hw/xen/xen_common.h | 16 ++++++++++++
 3 files changed, 66 insertions(+), 13 deletions(-)

diff --git a/configure b/configure
index dd73cce62f..55b67f9845 100755
--- a/configure
+++ b/configure
@@ -2114,6 +2114,7 @@ int main(void) {
 
   xfmem = xenforeignmemory_open(0, 0);
   xenforeignmemory_map2(xfmem, 0, 0, 0, 0, 0, 0, 0);
+  xenforeignmemory_map_resource(xfmem, 0, 0, 0, 0, 0, NULL, 0, 0);
 
   return 0;
 }
diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c
index 59e3122daf..0a8d1f6574 100644
--- a/hw/i386/xen/xen-hvm.c
+++ b/hw/i386/xen/xen-hvm.c
@@ -1235,13 +1235,37 @@ static void xen_wakeup_notifier(Notifier *notifier, void *data)
 
 static int xen_map_ioreq_server(XenIOState *state)
 {
+    void *addr = NULL;
+    xenforeignmemory_resource_handle *fres;
     xen_pfn_t ioreq_pfn;
     xen_pfn_t bufioreq_pfn;
     evtchn_port_t bufioreq_evtchn;
     int rc;
+
+    /*
+     * Attempt to map using the resource API and fall back to normal
+     * foreign mapping if this is not supported.
+     */
+    fres = xenforeignmemory_map_resource(xen_fmem, xen_domid,
+                                         XENMEM_resource_ioreq_server,
+                                         state->ioservid, 0, 2,
+                                         &addr,
+                                         PROT_READ|PROT_WRITE, 0);
+    if (fres != NULL) {
+        state->buffered_io_page = addr;
+        state->shared_page = addr + TARGET_PAGE_SIZE;
+    } else {
+        error_report("failed to map ioreq server resources: error %d handle=%p",
+                     errno, xen_xc);
+        if (errno != EOPNOTSUPP)
+            return -1;
+    }
     
     rc = xen_get_ioreq_server_info(xen_domid, state->ioservid,
-                                   &ioreq_pfn, &bufioreq_pfn,
+                                   (state->shared_page == NULL) ?
+                                   &ioreq_pfn : NULL,
+                                   (state->buffered_io_page == NULL) ?
+                                   &bufioreq_pfn : NULL,
                                    &bufioreq_evtchn);
     if (rc < 0) {
         error_report("failed to get ioreq server info: error %d handle=%p",
@@ -1249,24 +1273,36 @@ static int xen_map_ioreq_server(XenIOState *state)
         return rc;
     }
 
-    DPRINTF("shared page at pfn %lx\n", ioreq_pfn);
-    DPRINTF("buffered io page at pfn %lx\n", bufioreq_pfn);
+    if (state->shared_page == NULL)
+        DPRINTF("shared page at pfn %lx\n", ioreq_pfn);
+    
+    if (state->buffered_io_page == NULL)
+        DPRINTF("buffered io page at pfn %lx\n", bufioreq_pfn);
+    
     DPRINTF("buffered io evtchn is %x\n", bufioreq_evtchn);
 
-    state->shared_page = xenforeignmemory_map(xen_fmem, xen_domid,
-                                              PROT_READ|PROT_WRITE,
-                                              1, &ioreq_pfn, NULL);
     if (state->shared_page == NULL) {
-        error_report("map shared IO page returned error %d handle=%p",
-                     errno, xen_xc);
-        return -1;
+        state->shared_page = xenforeignmemory_map(xen_fmem, xen_domid,
+                                                  PROT_READ|PROT_WRITE,
+                                                  1, &ioreq_pfn, NULL);
+        if (state->shared_page == NULL) {
+            error_report("map shared IO page returned error %d handle=%p",
+                         errno, xen_xc);
+        }
     }
 
-    state->buffered_io_page = xenforeignmemory_map(xen_fmem, xen_domid,
-                                                   PROT_READ|PROT_WRITE,
-                                                   1, &bufioreq_pfn, NULL);
     if (state->buffered_io_page == NULL) {
-        error_report("map buffered IO page returned error %d", errno);
+        state->buffered_io_page = xenforeignmemory_map(xen_fmem, xen_domid,
+                                                       PROT_READ|PROT_WRITE,
+                                                       1, &bufioreq_pfn,
+                                                       NULL);
+        if (state->buffered_io_page == NULL) {
+            error_report("map buffered IO page returned error %d", errno);
+            return -1;
+        }
+    }
+
+    if (state->shared_page == NULL || state->buffered_io_page == NULL) {
         return -1;
     }
 
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 86c7f26106..6c59ab56e9 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -91,6 +91,22 @@ static inline void *xenforeignmemory_map2(xenforeignmemory_handle *h,
     return xenforeignmemory_map(h, dom, prot, pages, arr, err);
 }
 
+typedef void xenforeignmemory_resource_handle;
+
+static inline xenforeignmemory_resource_handle *xenforeignmemory_map_resource(
+    xenforeignmemory_handle *fmem, domid_t domid, unsigned int type,
+    unsigned int id, unsigned long frame, unsigned long nr_frames,
+    void **paddr, int prot, int flags)
+{
+    errno = EOPNOTSUPP;
+    return -1;
+}
+
+static inline void xenforeignmemory_unmap_resource(
+    xenforeignmemory_handle *fmem, xenforeignmemory_resource_handle *fres)
+{
+}
+
 #endif
 
 #if CONFIG_XEN_CTRL_INTERFACE_VERSION < 40900
-- 
2.11.0