From: Bruce Rogers Date: Wed, 9 Mar 2016 15:18:11 -0700 Subject: xen_disk: Add suse specific flush disable handling and map to QEMU equiv Add code to read the suse specific suse-diskcache-disable-flush flag out of xenstore, and set the equivalent flag within QEMU. Patch taken from Xen's patch queue, Olaf Hering being the original author. [bsc#879425] [BR: minor edits to pass qemu's checkpatch script] [BR: With qdevification of xen-block, code has changed significantly] Signed-off-by: Bruce Rogers Signed-off-by: Olaf Hering --- hw/block/xen-block.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c index 674953f1adeeaec6a81d9857144e..07b3be7b9b9f6093642363f13187 100644 --- a/hw/block/xen-block.c +++ b/hw/block/xen-block.c @@ -723,6 +723,8 @@ static XenBlockDrive *xen_block_drive_create(const char *id, const char *mode = qdict_get_try_str(opts, "mode"); const char *direct_io_safe = qdict_get_try_str(opts, "direct-io-safe"); const char *discard_enable = qdict_get_try_str(opts, "discard-enable"); + const char *suse_diskcache_disable_flush = qdict_get_try_str(opts, + "suse-diskcache-disable-flush"); char *driver = NULL; char *filename = NULL; XenBlockDrive *drive = NULL; @@ -803,6 +805,16 @@ static XenBlockDrive *xen_block_drive_create(const char *id, } } + if (suse_diskcache_disable_flush) { + unsigned long value; + if (!qemu_strtoul(suse_diskcache_disable_flush, NULL, 2, &value) && !!value) { + QDict *cache_qdict = qdict_new(); + + qdict_put_bool(cache_qdict, "no-flush", true); + qdict_put_obj(file_layer, "cache", QOBJECT(cache_qdict)); + } + } + /* * It is necessary to turn file locking off as an emulated device * may have already opened the same image file.