From d73cd42893f4cdc06e6829fea2347bb92cb789d1 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Mon, 15 Sep 2008 16:44:55 -0400 Subject: [ARM] kmap support The kmap virtual area borrows a 2MB range at the top of the 16MB area below PAGE_OFFSET currently reserved for kernel modules and/or the XIP kernel. This 2MB corresponds to the range covered by 2 consecutive second-level page tables, or a single pmd entry as seen by the Linux page table abstraction. Because XIP kernels are unlikely to be seen on systems needing highmem support, there shouldn't be any shortage of VM space for modules (14 MB for modules is still way more than twice the typical usage). Because the virtual mapping of highmem pages can go away at any moment after kunmap() is called on them, we need to bypass the delayed cache flushing provided by flush_dcache_page() in that case. The atomic kmap versions are based on fixmaps, and __cpuc_flush_dcache_page() is used directly in that case. Signed-off-by: Nicolas Pitre --- arch/arm/mm/Makefile | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm/mm/Makefile') diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 480f78a3611a..185e7dc7dcf2 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_MODULES) += proc-syms.o obj-$(CONFIG_ALIGNMENT_TRAP) += alignment.o obj-$(CONFIG_DISCONTIGMEM) += discontig.o +obj-$(CONFIG_HIGHMEM) += highmem.o obj-$(CONFIG_CPU_ABRT_NOMMU) += abort-nommu.o obj-$(CONFIG_CPU_ABRT_EV4) += abort-ev4.o -- cgit v1.2.3