Messages in this thread | | | Date | Tue, 08 Apr 2014 12:54:14 +0800 | From | Chen Gang <> | Subject | Re: 回复: [PATCH] arch:unicore32:mm: a dd devmem is allowed() to support STRICT DEVMEM |
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On 04/08/2014 11:20 AM, 管雪涛 wrote: > I'd like to put the code into asm/io.h, and make it static. >
It sounds OK to me, but I don't know why the other architectures (e.g. arm, powerpc, x86) put them into ".c".
iomem_is_exclusive() and page_is_ram() are all extern functions, so for me, devmem_is_allowed() is shot enough to be as inline function.
>> +#ifdef CONFIG_STRICT_DEVMEM >> +/* >> + * devmem_is_allowed() checks to see if /dev/mem access to a certain >> + * address is valid. The argument is a physical page number. >> + * We mimic x86 here by disallowing access to system RAM as well as >> + * device-exclusive MMIO regions. This effectively disable read()/write() >> + * on /dev/mem. >> + */ >> +static int devmem_is_allowed(unsigned long pfn)
How about "static inline int devmem_is_allowed(unsigned long pfn)"?
>> +{ >> + if (iomem_is_exclusive(pfn << PAGE_SHIFT)) >> + return 0; >> + if (!page_is_ram(pfn)) >> + return 1; >> + return 0; >> +} >> +#endif /* CONFIG_STRICT_DEVMEM */ > > Thanks, > > Acked-by: Xuetao Guan <gxt@mprc.pku.edu.cn> >
[...]
Thanks. -- Chen Gang
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