From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 5 Jun 2001 13:54:15 -0400
From: cohutta <cohutta@MailAndNews.com>
Subject: temp. mem mappings
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hi-

i'm trying to map some memory during kernel init.
(this is x86-specific.)
this should be temporary, unmapped after use.
this memory is not in the low identity-mapped 8 MB.

currently i have this sorta working by using a new fixed
mapping (linux/include/asm-i386/fixmap.h) and calling
set_fixmap() which calls set_pte_phys().
after i use (access, read-only) this memory, i try to
unmap it so that i can use the same virtual address
again by calling set_fixmap() again.
i use pte_clear() to unmap it.
however the next time that i call set_fixmap(),
set_pte_phys() gives me a pte_ERROR()...because the
pte hasn't been cleared (?).
but the new mapping seems to work.

i tried to make this similar to linux/include/asm-i386/highmem.h.

what is the a preferred/correct method to map and unmap memory
temporarily?

thanks.
/cohutta/

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