------ Forwarded Message From: girish <girishvg@xxxxxxxxx> Date: Tue, 26 Sep 2006 11:22:26 +0900 To: Atsushi Nemoto <anemo@xxxxxxxxxxxxx> Cc: "linux-mips@xxxxxxxxxxxxxx" <git-commits@xxxxxxxxxxxxxx> Conversation: [PATCH] cleanup hardcoding __pa/__va macros etc. (take-2) Subject: Re: [PATCH] cleanup hardcoding __pa/__va macros etc. (take-2) The idea is to differentiate the Kseg0/Kseg1 segments in the physical area. Beyond these areas lies the mapped area (or the HIGHMEM). What complicates this matter further is their overlapping nature. The __pa()/__va() treated all addresses mapped into PAGE_OFFSET (8000_0000) area. The effort is to correctly differentiate these areas. I could not think of any better solution & the only simplification I came up with - #ifdef CONFIG_32BIT /* 8000_0000 & above */ #define ISMAPPEDPA(x) ((x) > KSEG0) /* below 2000_0000 */ #define ISUNMAPPEDVA(x) ((x) < HIGHMEM_START) #else #define ISMAPPEDPA(x) (1) #define ISMAPPEDVA(x) (1) #endif #define ___pa(x) ((unsigned long) (x) - KSEGX((x))) #define __pa(x) (ISUNMAPPEDPA(x) ? ___pa((x)) : (x)) #define ___va(x) ((void *)((unsigned long) (x) + KSEG0)) #define __va(x) (ISUNMAPPEDVA(x) ? ___va((x)) : (x)) On 9/26/06 12:43 AM, "Atsushi Nemoto" <anemo@xxxxxxxxxxxxx> wrote: > On Mon, 25 Sep 2006 23:51:46 +0900, girish <girishvg@xxxxxxxxx> wrote: >> Here is the patch again, attached as a text file. I don't have idea how >> these macros should be on a 64bit machine, so I just left them as it is. >> Could you please verify these macros again? > > Well, I should ask first: Why do you change __pa() and __va() ? > > I can not see point of ISMAPPED() testing. And these macros are used > quite often so they should be as fast as possible. > > --- > Atsushi Nemoto ------ End of Forwarded Message
