On Mon, Jun 8, 2015 at 9:27 AM, Andy Shevchenko <[email protected]> wrote: > On Thu, Jun 4, 2015 at 12:34 AM, Dan Williams <[email protected]> > wrote: >> Existing users of ioremap_cache() are mapping memory that is known in >> advance to not have i/o side effects. These users are forced to cast >> away the __iomem annotation, or otherwise neglect to fix the sparse >> errors thrown when dereferencing pointers to this memory. Provide >> memremap_*() as a non __iomem annotated ioremap_*(). >> >> The ARCH_HAS_MEMREMAP kconfig symbol is introduced for archs to assert >> that it is safe to recast / reuse the return value from ioremap as a >> normal pointer to memory. In other words, archs that mandate specific >> accessors for __iomem are not memremap() capable and drivers that care, >> like pmem, can add a dependency to disable themselves on these archs. > > One minor comment. Otherwise looks good for me. > > [] > >> --- a/kernel/resource.c >> +++ b/kernel/resource.c > >> @@ -528,6 +528,45 @@ int region_is_ram(resource_size_t start, unsigned long >> size) >> return ret; >> } >> >> +#ifdef CONFIG_ARCH_HAS_MEMREMAP >> +/* >> + * memremap() is "ioremap" for cases where it is known that the resource >> + * being mapped does not have i/o side effects and the __iomem >> + * annotation is not applicable. >> + */ >> +static bool memremap_valid(resource_size_t offset, size_t size) >> +{ >> + if (region_is_ram(offset, size) != 0) { >> + WARN_ONCE(1, "memremap attempted on ram %pa size: %zd\n", > > %zu
Sure, thanks for taking a look Andy! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
