We can let a driver handle dma mapping errors using these-> 1.Reduce the size of a receive ring. This will free some possibly remapped memory, reducing pressure on iommu. We also need to printk a message so that a user knows the reason why receive ring was shrunk. Growing it when iommu pressure goes down will result in a ping-pong. 2. Force processing of receive and transmit ring. This will ensure that the buffers processed by hardware are freed, reducing iommu pressure.
3. If we need to do (1) and (2) a predefined number of times (say 20), stop the queue. Stopping the queue in general will cause a ping-pong, so it should be avoided as far as possible. -Amit On Thursday 07 December 2006 06:28, Stephen Hemminger wrote: > The more robust way would be to stop the queue (like flow control) > and return busy. You would need a timer though to handle the case > where some disk i/o stole all the mappings and then network device flow > blocked. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
