[PATCH v3 RESEND 15/17] ARM: mm: use physical addresses in highmem sanity checks
From: Cyril Chemparathy <hidden>
Date: 2012-09-21 16:01:58
Also in:
lkml
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
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 <redacted> Signed-off-by: Vitaly Andrianov <redacted> Acked-by: Nicolas Pitre <redacted> --- 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 8db7c74..fcdc185 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c@@ -895,6 +895,7 @@ 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];
@@ -904,8 +905,7 @@ 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;
@@ -914,8 +914,8 @@ 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");
@@ -924,12 +924,12 @@ 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;
@@ -949,8 +949,7 @@ 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,
@@ -962,9 +961,8 @@ 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,
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1.7.9.5