Messages in this thread | | | Date | Tue, 10 Jun 2014 17:33:33 -0400 | From | Matthew Wilcox <> | Subject | Re: [PATCH v7] NVMe: conversion to blk-mq |
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On Tue, Jun 10, 2014 at 03:21:18PM -0600, Keith Busch wrote: > Yeah, nvme_setup_prps is probably the least readable code in this driver. > Maybe some comments are in order here... > > There are two rules for an SGL to be mappable to a PRP: > > 1. Every element must have zero page offset, except the first. > > 2. Every element must end on a page boundary, except the last.
Or to put it another way, NVMe PRPs only support I/Os that describe a single range of virtual memory.
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