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Date: Thu, 20 Mar 2008 18:08:55 +0200
From: "Mr Y" <yonyossef.lists@gmail.com>
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Subject: bus_dmamem_alloc
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I'm trying to use bus_dmamem_alloc. The function man says:

    /*
     * Allocate a piece of memory that can be efficiently mapped into
     * bus device space based on the constraints listed in the dma tag.
     * A dmamap to for use with dmamap_load is also allocated.
     */

so I'm running:

err =
bus_dmamem_alloc(ring->dma_tag, &ring->buf,
BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW, &ring->dma_map);

but after calling bus_dmamem_allloc the dma_map variable is still NULL. is
this OK?

Thx, Yony