[PATCH RFC 4/4] tool/xen-access: Add support for PV domains

[Aravindh Puthiyaparambil <aravindp@cisco.com>]

Add support to the xen-access test program for it work with PV domains.
The main difference is that for PV domains, unlike HVM domains,
xc_mem_access_create_ring_page() has to be called as the page is not
created during domain creation time. PV domains do not need to set
all individual page access permissions during setup and teardown. Enabling
and disabling mem_access does that indirectly.

Signed-off-by: Aravindh Puthiyaprambil <aravindp@cisco.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
---
 tools/tests/xen-access/xen-access.c | 122 ++++++++++++++++++++++++------------
 1 file changed, 81 insertions(+), 41 deletions(-)

diff --git a/tools/tests/xen-access/xen-access.c b/tools/tests/xen-access/xen-access.c
index 0a84bd5..f9883f4 100644
--- a/tools/tests/xen-access/xen-access.c
+++ b/tools/tests/xen-access/xen-access.c
@@ -114,7 +114,8 @@ typedef struct xenaccess {
 } xenaccess_t;
 
 static int interrupted;
-bool evtchn_bind = 0, evtchn_open = 0, mem_access_enable = 0;
+bool evtchn_bind = 0, evtchn_open = 0, mem_access_enable = 0, pv_ring_page = 0;
+bool hvm = 0;
 
 static void close_handler(int sig)
 {
@@ -173,7 +174,7 @@ int xenaccess_teardown(xc_interface *xch, xenaccess_t *xenaccess)
     if ( xenaccess->mem_event.ring_page )
         munmap(xenaccess->mem_event.ring_page, XC_PAGE_SIZE);
 
-    if ( mem_access_enable )
+    if ( mem_access_enable  || (!hvm && pv_ring_page) )
     {
         rc = xc_mem_access_disable(xenaccess->xc_handle,
                                    xenaccess->mem_event.domain_id);
@@ -245,9 +246,57 @@ xenaccess_t *xenaccess_init(xc_interface **xch_r, domid_t domain_id)
     /* Initialise lock */
     mem_event_ring_lock_init(&xenaccess->mem_event);
 
+    /* Get domaininfo */
+    xenaccess->domain_info = malloc(sizeof(xc_domaininfo_t));
+    if ( xenaccess->domain_info == NULL )
+    {
+        ERROR("Error allocating memory for domain info");
+        goto err;
+    }
+
+    rc = xc_domain_getinfolist(xenaccess->xc_handle, domain_id, 1,
+                               xenaccess->domain_info);
+    if ( rc != 1 )
+    {
+        ERROR("Error getting domain info");
+        goto err;
+    }
+
+    if ( xenaccess->domain_info->flags & XEN_DOMINF_hvm_guest )
+        hvm = 1;
+
+    DPRINTF("max_pages = %"PRIx64"\n", xenaccess->domain_info->max_pages);
+
+    if ( hvm )
+    {
+        rc = xc_get_hvm_param(xch, xenaccess->mem_event.domain_id,
+                              HVM_PARAM_ACCESS_RING_PFN, &ring_pfn);
+
+    }
+    else
+    {
+        rc = xc_mem_access_create_ring_page(xch, xenaccess->mem_event.domain_id);
+        if ( rc != 0 )
+        {
+            PERROR("Failed to set ring gfn\n");
+            goto err;
+        }
+
+        pv_ring_page = 1;
+
+        rc = xc_mem_access_get_ring_mfn(xch, xenaccess->mem_event.domain_id,
+                                        &ring_pfn);
+    }
+
+    if ( rc != 0 )
+    {
+        PERROR("Failed to get ring gfn\n");
+        goto err;
+    }
+
+    DPRINTF("ring_mfn: 0x%lx\n", ring_pfn);
+
     /* Map the ring page */
-    xc_get_hvm_param(xch, xenaccess->mem_event.domain_id, 
-                        HVM_PARAM_ACCESS_RING_PFN, &ring_pfn);
     mmap_pfn = ring_pfn;
     xenaccess->mem_event.ring_page = 
         xc_map_foreign_batch(xch, xenaccess->mem_event.domain_id, 
@@ -327,24 +376,6 @@ xenaccess_t *xenaccess_init(xc_interface **xch_r, domid_t domain_id)
                     xenaccess->mem_event.domain_id, 1, 0, &ring_pfn) )
         PERROR("Failed to remove ring from guest physmap");
 
-    /* Get domaininfo */
-    xenaccess->domain_info = malloc(sizeof(xc_domaininfo_t));
-    if ( xenaccess->domain_info == NULL )
-    {
-        ERROR("Error allocating memory for domain info");
-        goto err;
-    }
-
-    rc = xc_domain_getinfolist(xenaccess->xc_handle, domain_id, 1,
-                               xenaccess->domain_info);
-    if ( rc != 1 )
-    {
-        ERROR("Error getting domain info");
-        goto err;
-    }
-
-    DPRINTF("max_pages = %"PRIx64"\n", xenaccess->domain_info->max_pages);
-
     return xenaccess;
 
  err:
@@ -526,23 +557,28 @@ int main(int argc, char *argv[])
         goto exit;
     }
 
-    rc = xc_set_mem_access(xch, domain_id, default_access, 0,
-                           xenaccess->domain_info->max_pages);
-    if ( rc < 0 )
+    if ( hvm )
     {
-        ERROR("Error %d setting all memory to access type %d\n", rc,
-              default_access);
-        goto exit;
-    }
+        rc = xc_set_mem_access(xch, domain_id, default_access, 0,
+                               xenaccess->domain_info->max_pages);
+        if ( rc < 0 )
+        {
+            ERROR("Error %d setting all memory to access type %d\n", rc,
+                  default_access);
+            goto exit;
+        }
 
-    if ( int3 )
-        rc = xc_set_hvm_param(xch, domain_id, HVM_PARAM_MEMORY_EVENT_INT3, HVMPME_mode_sync);
-    else
-        rc = xc_set_hvm_param(xch, domain_id, HVM_PARAM_MEMORY_EVENT_INT3, HVMPME_mode_disabled);
-    if ( rc < 0 )
-    {
-        ERROR("Error %d setting int3 mem_event\n", rc);
-        goto exit;
+        if ( int3 )
+            rc = xc_set_hvm_param(xch, domain_id, HVM_PARAM_MEMORY_EVENT_INT3,
+                                  HVMPME_mode_sync);
+        else
+            rc = xc_set_hvm_param(xch, domain_id, HVM_PARAM_MEMORY_EVENT_INT3,
+                                  HVMPME_mode_disabled);
+        if ( rc < 0 )
+        {
+            ERROR("Error %d setting int3 mem_event\n", rc);
+            goto exit;
+        }
     }
 
     /* Wait for access */
@@ -554,10 +590,14 @@ int main(int argc, char *argv[])
 
             /* Unregister for every event */
             rc = xc_set_mem_access(xch, domain_id, XENMEM_access_rwx, ~0ull, 0);
-            rc = xc_set_mem_access(xch, domain_id, XENMEM_access_rwx, 0,
-                                   xenaccess->domain_info->max_pages);
-            rc = xc_set_hvm_param(xch, domain_id, HVM_PARAM_MEMORY_EVENT_INT3, HVMPME_mode_disabled);
-
+            if ( hvm )
+            {
+                rc = xc_set_mem_access(xch, domain_id, XENMEM_access_rwx, 0,
+                                       xenaccess->domain_info->max_pages);
+                rc = xc_set_hvm_param(xch, domain_id,
+                                      HVM_PARAM_MEMORY_EVENT_INT3,
+                                      HVMPME_mode_disabled);
+            }
             shutting_down = 1;
         }
 
-- 
1.9.1