Messages in this thread | | | Date | Mon, 22 Feb 2016 11:05:51 -0800 | Subject | Re: [RFC PATCH 1/2] memremap: add arch specific hook for MEMREMAP_WB mappings | From | Dan Williams <> |
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On Mon, Feb 22, 2016 at 6:02 AM, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote: > Currently, the memremap code serves MEMREMAP_WB mappings directly from > the kernel direct mapping, unless the region is in high memory, in which > case it falls back to using ioremap_cache(). However, the semantics of > ioremap_cache() are not unambiguously defined, and on ARM, it will > actually result in a mapping type that differs from the attributes used > for the linear mapping, and for this reason, the ioremap_cache() call > fails if the region is part of the memory managed by the kernel. > > So instead, implement an optional hook 'arch_memremap_wb' whose default > implementation calls ioremap_cache() as before, but which can be > overridden by the architecture to do what is appropriate for it. >
Acked-by: Dan Williams <dan.j.williams@intel.com>
I still have patches pending to delete ioremap_cache() from ARM and require memremap() to be used for cacheable mappings. Do you see any use for ioremap_cache() on ARM after this change?
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