xen/sys/hypervisor: change writable_pt to features

/sys/hypervisor/properties/writable_pt was misnamed.  Rename to features,
expressed as a bit array in hex.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

1 files changed, 26 insertions, 15 deletions

diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c
index cb29d1ccf0d9..1267d6fcc0c7 100644
--- a/drivers/xen/sys-hypervisor.c
+++ b/drivers/xen/sys-hypervisor.c
@@ -293,37 +293,48 @@ static ssize_t pagesize_show(struct hyp_sysfs_attr *attr, char *buffer)
 
 HYPERVISOR_ATTR_RO(pagesize);
 
-/* eventually there will be several more features to export */
 static ssize_t xen_feature_show(int index, char *buffer)
 {
-        int ret = -ENOMEM;
-        struct xen_feature_info *info;
+        ssize_t ret;
+        struct xen_feature_info info;
 
-        info = kmalloc(sizeof(struct xen_feature_info), GFP_KERNEL);
-        if (info) {
-                info->submap_idx = index;
-                ret = HYPERVISOR_xen_version(XENVER_get_features, info);
-                if (!ret)
-                        ret = sprintf(buffer, "%d\n", info->submap);
-                kfree(info);
-        }
+        info.submap_idx = index;
+        ret = HYPERVISOR_xen_version(XENVER_get_features, &info);
+        if (!ret)
+                ret = sprintf(buffer, "%08x", info.submap);
 
         return ret;
 }
 
-static ssize_t writable_pt_show(struct hyp_sysfs_attr *attr, char *buffer)
+static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer)
 {
-        return xen_feature_show(XENFEAT_writable_page_tables, buffer);
+        ssize_t len;
+        int i;
+
+        len = 0;
+        for (i = XENFEAT_NR_SUBMAPS-1; i >= 0; i--) {
+                int ret = xen_feature_show(i, buffer + len);
+                if (ret < 0) {
+                        if (len == 0)
+                                len = ret;
+                        break;
+                }
+                len += ret;
+        }
+        if (len > 0)
+                buffer[len++] = '\n';
+
+        return len;
 }
 
-HYPERVISOR_ATTR_RO(writable_pt);
+HYPERVISOR_ATTR_RO(features);
 
 static struct attribute *xen_properties_attrs[] = {
         &capabilities_attr.attr,
         &changeset_attr.attr,
         &virtual_start_attr.attr,
         &pagesize_attr.attr,
-        &writable_pt_attr.attr,
+        &features_attr.attr,
         NULL
 };