Messages in this thread | | | Date | Wed, 26 Aug 2015 14:46:49 +0200 | From | Christoph Hellwig <> | Subject | Re: [PATCH v2 9/9] devm_memremap_pages: protect against pmem device unbind |
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On Tue, Aug 25, 2015 at 09:28:13PM -0400, Dan Williams wrote: > Given that: > > 1/ device ->remove() can not be failed > > 2/ a pmem device may be unbound at any time > > 3/ we do not know what other parts of the kernel are actively using a > 'struct page' from devm_memremap_pages() > > ...provide a facility for active usages of device memory to block pmem > device unbind. With a percpu_ref it should be feasible to take a > reference on a per-I/O or other high frequency basis.
Without a caller of get_page_map this is just adding dead code. I'd suggest to group it in a series with that caller.
Also if the page_map gets exposed in a header the name is a bit too generic. memremap_map maybe?
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