qemu-xen-traditional: use O_DIRECT to open disk images for IDE

[ Major performance fix. -iwj ]

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 1307e42a4b3c1102d75401bc0cffb4eb6c9b7a38)

diff --git a/xenstore.c b/xenstore.c
index 4c483e29523129f825e7b889555ff88be5952edf..ac90366f0d9463ca407ccb14150edde42a34f725 100644 (file)
--- a/xenstore.c
+++ b/xenstore.c
@@ -643,7 +643,7 @@ void xenstore_parse_domain_config(int hvm_domid)
            }
             pstrcpy(bs->filename, sizeof(bs->filename), params);
 
-            flags = BDRV_O_CACHE_WB; /* snapshot and write-back */
+            flags = BDRV_O_NOCACHE;
             is_readonly = 0;
             if (pasprintf(&buf, "%s/mode", bpath) == -1)
                 continue;