Messages in this thread | | | Date | Fri, 08 Jun 2007 09:50:17 +0200 | From | Carsten Otte <> | Subject | Re: [PATCH 2.6.21] cramfs: add cramfs Linear XIP |
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Christoph Hellwig wrote: > We can have a simpler variant as a start if we really want. But we > need to pass it through the mtd layer. There is a reason we have this > thing called devices drivers, and we don't want to add knowledge of > ioremap to the filesystems and have users find out physical addresses > of their flash to pass it as mount option. I see your poing with regard to layering, and I agree to it. In order to do ioremap/iounmap at least we need a counterpart put_xip_page thing to do iounmap in that path. Our dcss segments on 390 did not raise that requirement: they had a permanent kernel mapping. The quiz question to me is: why don't we establish a permanenet mapping of the entire thing from mount() to unmount(). That eliminates the need to do iomap/iounmap, eliminates the need to have put_xip_page, and eliminates to care about what layer would do this. Would work for cramfs, won't work for read+write flash filesystems. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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