From 82f667046ec895552caf2f7a4c6841c530bfc215 Mon Sep 17 00:00:00 2001 From: Cyril Chemparathy Date: Fri, 20 Jul 2012 12:01:23 -0400 Subject: [PATCH] ARM: mm: use physical addresses in highmem sanity checks This patch modifies the highmem sanity checking code to use physical addresses instead. This change eliminates the wrap-around problems associated with the original virtual address based checks, and this simplifies the code a bit. The one constraint imposed here is that low physical memory must be mapped in a monotonically increasing fashion if there are multiple banks of memory, i.e., x < y must => pa(x) < pa(y). Signed-off-by: Cyril Chemparathy Signed-off-by: Vitaly Andrianov Acked-by: Nicolas Pitre Tested-by: Santosh Shilimkar Tested-by: Subash Patel Signed-off-by: Will Deacon --- arch/arm/mm/mmu.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index b7ce65a8237..fc6ff1a9db5 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -988,6 +988,7 @@ phys_addr_t arm_lowmem_limit __initdata = 0; void __init sanity_check_meminfo(void) { int i, j, highmem = 0; + phys_addr_t vmalloc_limit = __pa(vmalloc_min - 1) + 1; for (i = 0, j = 0; i < meminfo.nr_banks; i++) { struct membank *bank = &meminfo.bank[j]; @@ -997,8 +998,7 @@ void __init sanity_check_meminfo(void) highmem = 1; #ifdef CONFIG_HIGHMEM - if (__va(bank->start) >= vmalloc_min || - __va(bank->start) < (void *)PAGE_OFFSET) + if (bank->start >= vmalloc_limit) highmem = 1; bank->highmem = highmem; @@ -1007,8 +1007,8 @@ void __init sanity_check_meminfo(void) * Split those memory banks which are partially overlapping * the vmalloc area greatly simplifying things later. */ - if (!highmem && __va(bank->start) < vmalloc_min && - bank->size > vmalloc_min - __va(bank->start)) { + if (!highmem && bank->start < vmalloc_limit && + bank->size > vmalloc_limit - bank->start) { if (meminfo.nr_banks >= NR_BANKS) { printk(KERN_CRIT "NR_BANKS too low, " "ignoring high memory\n"); @@ -1017,12 +1017,12 @@ void __init sanity_check_meminfo(void) (meminfo.nr_banks - i) * sizeof(*bank)); meminfo.nr_banks++; i++; - bank[1].size -= vmalloc_min - __va(bank->start); - bank[1].start = __pa(vmalloc_min - 1) + 1; + bank[1].size -= vmalloc_limit - bank->start; + bank[1].start = vmalloc_limit; bank[1].highmem = highmem = 1; j++; } - bank->size = vmalloc_min - __va(bank->start); + bank->size = vmalloc_limit - bank->start; } #else bank->highmem = highmem; @@ -1042,8 +1042,7 @@ void __init sanity_check_meminfo(void) * Check whether this memory bank would entirely overlap * the vmalloc area. */ - if (__va(bank->start) >= vmalloc_min || - __va(bank->start) < (void *)PAGE_OFFSET) { + if (bank->start >= vmalloc_limit) { printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx " "(vmalloc region overlap).\n", (unsigned long long)bank->start, @@ -1055,9 +1054,8 @@ void __init sanity_check_meminfo(void) * Check whether this memory bank would partially overlap * the vmalloc area. */ - if (__va(bank->start + bank->size - 1) >= vmalloc_min || - __va(bank->start + bank->size - 1) <= __va(bank->start)) { - unsigned long newsize = vmalloc_min - __va(bank->start); + if (bank->start + bank->size > vmalloc_limit) + unsigned long newsize = vmalloc_limit - bank->start; printk(KERN_NOTICE "Truncating RAM at %.8llx-%.8llx " "to -%.8llx (vmalloc region overlap).\n", (unsigned long long)bank->start, -- 2.43.2