[dm-devel] shouldn't io_restrictions indicate whether or not I/O may be clus tered?

[goggin, edward]

Shouldn't the device-mapper io_restrictions structure include a field
to indicate whether or not I/O may be clustered as indicated by the
setting of the QUEUE_CLUSTER_FLAG bit of the queue_flags field
of the request_queue structures for the target devices?  Otherwise,
couldn't we end up with some I/Os terminated in the I/O prep phase
due to an excess of physical segments in the I/O request?