[PATCH] arm/arm64: KVM: introduce new mapping API for percpu mappings
Christoffer Dall
christoffer.dall at linaro.org
Fri Nov 15 11:10:04 EST 2013
On Fri, Nov 15, 2013 at 03:40:08PM +0000, Marc Zyngier wrote:
> Using virt_to_phys on percpu mappings is horribly wrong (my own bad).
> Thankfully, the kernel offers a way to obtain the physical address
> of such a mapping.
>
> Add a new create_hyp_percpu_mappings function to deal with those.
>
> Reported-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
> Cc: Christoffer Dall <christoffer.dall at linaro.org>
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> ---
So, I find this nicer, somehow, what do you think:
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 3719583..dd531ba 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -334,6 +334,15 @@ out:
return err;
}
+static phys_addr_t kvm_kaddr_to_phys(void *kaddr)
+{
+ if (!is_vmalloc_addr(kaddr))
+ return __pa(kaddr);
+ else
+ return page_to_phys(vmalloc_to_page(kaddr)) +
+ offset_in_page(kaddr);
+}
+
/**
* create_hyp_mappings - duplicate a kernel virtual address range in Hyp mode
* @from: The virtual kernel start address of the range
@@ -345,16 +354,24 @@ out:
*/
int create_hyp_mappings(void *from, void *to)
{
- unsigned long phys_addr = virt_to_phys(from);
+ phys_addr_t phys_addr;
+ unsigned long virt_addr;
unsigned long start = KERN_TO_HYP((unsigned long)from);
unsigned long end = KERN_TO_HYP((unsigned long)to);
- /* Check for a valid kernel memory mapping */
- if (!virt_addr_valid(from) || !virt_addr_valid(to - 1))
- return -EINVAL;
+ for (virt_addr = start; virt_addr < end; virt_addr += PAGE_SIZE) {
+ int err;
- return __create_hyp_mappings(hyp_pgd, start, end,
- __phys_to_pfn(phys_addr), PAGE_HYP);
+ phys_addr = kvm_kaddr_to_phys(from + virt_addr - start);
+ err = __create_hyp_mappings(hyp_pgd, virt_addr,
+ virt_addr + PAGE_SIZE,
+ __phys_to_pfn(phys_addr),
+ PAGE_HYP);
+ if (err)
+ return err;
+ }
+
+ return 0;
}
/**
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