From b2f3f8e649645dc699129dbe46fe6b9112aee105 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Wed, 7 Nov 2007 09:22:31 +0000 Subject: [PATCH] Enable loopback disk image files on readonly nfs filesystem. When we losetup a file on readonly nfs filesystem, it fails with: # losetup /dev/loop7 /data/vm/xen_el5_i386_para/system.raw /data/vm/xen_el5_i386_para/system.raw: Permission denied New version of losetup has add a "-r" option for readonly loop, which Linux kernel has supported for a long time. Some distribution (EL5 update, Fedora 8, etc.) have shipped it. This patch benefit this option while doesn't break the old versions of losetup. Signed-off-by: Zhigang Wang --- tools/examples/block | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/examples/block b/tools/examples/block index 411e6813fe..2f3a645d7a 100644 --- a/tools/examples/block +++ b/tools/examples/block @@ -326,7 +326,10 @@ mount it read-write in a guest domain." fatal 'Failed to find an unused loop device' fi - do_or_die losetup "$loopdev" "$file" + status=$(losetup "$loopdev" "$file" || echo "failed") + if [ -n "$status" ]; then + do_or_die losetup -r "$loopdev" "$file" + fi xenstore_write "$XENBUS_PATH/node" "$loopdev" write_dev "$loopdev" release_lock "block" -- 2.30.2