Commit 3159f372 authored by Sergey Dyasly's avatar Sergey Dyasly Committed by Russell King

ARM: 7840/1: LPAE: don't reject mapping /dev/mem above 4GB

With LPAE enabled, physical address space is larger than 4GB. Allow mapping any
part of it via /dev/mem by using PHYS_MASK to determine valid range.

PHYS_MASK covers 40 bits with LPAE enabled and 32 bits otherwise.
Reported-by: default avatarVassili Karpov <av1474@comtv.ru>
Signed-off-by: default avatarSergey Dyasly <dserrg@gmail.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 31d141e3
......@@ -202,13 +202,11 @@ int valid_phys_addr_range(phys_addr_t addr, size_t size)
}
/*
* We don't use supersection mappings for mmap() on /dev/mem, which
* means that we can't map the memory area above the 4G barrier into
* userspace.
* Do not allow /dev/mem mappings beyond the supported physical range.
*/
int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
{
return !(pfn + (size >> PAGE_SHIFT) > 0x00100000);
return (pfn + (size >> PAGE_SHIFT)) <= (1 + (PHYS_MASK >> PAGE_SHIFT));
}
#ifdef CONFIG_STRICT_DEVMEM
......
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