From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: RE: [PATCH] qlcnic: dma address align check
Date: Tue, 26 Oct 2010 12:30:33 +0200
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To: Amit Salecha <amit.salecha@qlogic.com>
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Le mardi 26 octobre 2010 =C3=A0 05:04 -0500, Amit Salecha a =C3=A9crit =
:

> Is it ? I am not aware about such calculation.

Yes it is

> Is pci_alloc_consistent guarantee to give PAGE align dma address ?

I believe so

By the way, you should use dma_alloc_coherent() instead of
pci_alloc_consistent() so that you can use GFP_KERNEL allocations
instead of GFP_ATOMIC, it might help in low memory conditions (if you
dont hold a spinlock at this point)


If TX_DESC_RINGSIZE(tx_ring) is not a power of two, then yes you could
probably add 64 bytes and avoid allocating a full page only for the u32
field ;)