[PATCH 1/7] omap: iommu: migrate to the generic IOMMU API

On Wed, Aug 24, 2011 at 08:46:13AM -0400, Ohad Ben-Cohen wrote:

On Tue, Aug 23, 2011 at 5:59 PM, Ohad Ben-Cohen [off-list ref] wrote:

quoted

On Tue, Aug 23, 2011 at 5:07 PM, Roedel, Joerg [off-list ref] wrote:

quoted

Can this be easily converted to a spin_lock?

Sure, thanks for reviewing.

Taking a second look, I don't think it's necessary - the mutex isn't
used to protect the page table. The page table is protected by a spin
lock, so map/unmap operations can be called from an atomic context.

The mutex is only part of the attach/deattach operations, which are
already used today in process context, so I guess it's safe.

Yes, it should be safe in your context. But the iommu-api is generic and
I would prefer that all functions it provides can be called from any
context.
Or is the time required for attaching/detaching too long so that it
makes sense to put secondary threads to sleep?

	Joerg

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