libxl, hotplug/Linux: default to phy backend for raw format file

Modify libxl to allow raw format file to use phy backend.

For the hotplug script part, learn from NetBSD's block hotplug script --
test the path and determine the actual type of file (block device or
regular file) then use the actual type to determine which branch to run.

With these changes, plus the current ordering of backend preference
(phy > qdisk > tap), we will use phy backend for raw format file by
default.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/hotplug/Linux/block b/tools/hotplug/Linux/block
index da26e221dc83f7a380d894dea41225a7aedf854d..8d2ee9d213c58c90f4ff42b96897d3138b1c20ce 100644 (file)
--- a/tools/hotplug/Linux/block
+++ b/tools/hotplug/Linux/block
@@ -206,6 +206,13 @@ and so cannot be mounted ${m2}${when}."
 
 
 t=$(xenstore_read_default "$XENBUS_PATH/type" 'MISSING')
+p=$(xenstore_read "$XENBUS_PATH/params")
+mode=$(xenstore_read "$XENBUS_PATH/mode")
+if [ -b "$p" ]; then
+    truetype="phy"
+elif [ -f "$p" ]; then
+    truetype="file"
+fi
 
 case "$command" in
   add)
@@ -217,16 +224,11 @@ case "$command" in
       exit 0
     fi
 
-    if [ -n "$t" ]
-    then
-      p=$(xenstore_read "$XENBUS_PATH/params")
-      mode=$(xenstore_read "$XENBUS_PATH/mode")
-    fi
     FRONTEND_ID=$(xenstore_read "$XENBUS_PATH/frontend-id")
     FRONTEND_UUID=$(xenstore_read_default \
             "/local/domain/$FRONTEND_ID/vm" 'unknown')
 
-    case $t in 
+    case $truetype in
       phy)
         dev=$(expand_dev $p)
 
@@ -319,7 +321,7 @@ mount it read-write in a guest domain."
     ;;
 
   remove)
-    case $t in 
+    case $truetype in
       phy)
        exit 0
        ;;

diff --git a/tools/libxl/libxl_linux.c b/tools/libxl/libxl_linux.c
index 37815eb650701ba8e5592781002ed160d94df1aa..3cfa6dacc67e91f6e6a9bda10b4b5163eaad4100 100644 (file)
--- a/tools/libxl/libxl_linux.c
+++ b/tools/libxl/libxl_linux.c
@@ -19,11 +19,11 @@
  
 int libxl__try_phy_backend(mode_t st_mode)
 {
-    if (!S_ISBLK(st_mode)) {
-        return 0;
+    if (S_ISBLK(st_mode) || S_ISREG(st_mode)) {
+        return 1;
     }
 
-    return 1;
+    return 0;
 }
 
 #define EXT_SHIFT 28