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Date: Sat, 4 Apr 2015 07:27:14 -0400
From: Sowmini Varadhan <sowmini.varadhan@oracle.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH v8 RFC 1/3] sparc: Break up monolithic iommu table/lock
 into finer graularity pools and lock
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One last question before I spin out v9.. the dma_mask code
is a bit confusing to me, so I want to make sure... the code is 

> if (limit + tbl->it_offset > mask) {
>               limit = mask - tbl->it_offset + 1;
>               /* If we're constrained on address range, first try
>                * at the masked hint to avoid O(n) search complexity,
>                * but on second pass, start at 0 in pool 0.
>                */
>               if ((start & mask) >= limit || pass > 0) {
>                       spin_unlock(&(pool->lock));
>                       pool = &(tbl->pools[0]);
>                       spin_lock(&(pool->lock));
>                       start = pool->start;

So here I would need to mark need_flush to true, right?


--Sowmini