On Thu, 15 May 2014, Richard Lee wrote:
> Static vm area boundary check:
>
> paddr1 --->| |
> | |
> |-------| <-\--- svm->vm->addr(is page aligned)
> paddr2 --->| | |
> | --| <--|-- svm->vm->phys_addr
> | | |
> paddr3 --->| | |
> | | |
> |-------| <--|-- next page boundary
> | | |
> paddr4 --->| | | <----- svm->vm->size(including guard page)
> | | |
> | | |
> max paddr_end -->|-------| <--|-- svm->vm's phys_addr_end
> | ///// | |
> paddr5 --->| guard | |
> | page | |
> | ///// | |
> ------- <-/--- svm->vm->addr + svm->vm_size
>
> <1> If the paddr == paddr1, then continue;
> <2> If the paddr == paddr2~paddr4 and paddr_end > phys_addr_end,
> then continue;
> <3> if the paddr >= paddr5 then continue;
>
> Signed-off-by: Richard Lee <superlibj8...@gmail.com>
instead of doing this repeatedly, why not simply ensure the recorded
static vm information is already page aligned in the first place?
> ---
>
>
> Change in V2:
> - PAGE_SIZE --> PAGE_MASK
> - remove the 'size' page size align operation.
>
>
>
>
>
>
> arch/arm/mm/ioremap.c | 40 ++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 38 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
> index be69333..f235ab7 100644
> --- a/arch/arm/mm/ioremap.c
> +++ b/arch/arm/mm/ioremap.c
> @@ -47,16 +47,52 @@ static struct static_vm *find_static_vm_paddr(phys_addr_t
> paddr,
> {
> struct static_vm *svm;
> struct vm_struct *vm;
> + size_t offset;
> +
> + offset = paddr & ~PAGE_MASK;
>
> list_for_each_entry(svm, &static_vmlist, list) {
> + phys_addr_t paddr_end, phys_addr_end;
> + size_t vmoff;
> +
> vm = &svm->vm;
> if (!(vm->flags & VM_ARM_STATIC_MAPPING))
> continue;
> if ((vm->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
> continue;
>
> - if (vm->phys_addr > paddr ||
> - paddr + size - 1 > vm->phys_addr + vm->size - 1)
> + /* Static vm area boundary check:
> + *
> + * paddr1 --->| |
> + * | |
> + * |-------| <-\--- svm->vm->addr(page aligned)
> + * paddr2 --->| | |
> + * | --| <--|-- svm->vm->phys_addr
> + * | | |
> + * paddr3 --->| | |
> + * | | |
> + * |-------| <--|-- next page boundary
> + * | | |
> + * paddr4 --->| | | <----- svm->vm->size,
> + * | | | including guard page
> + * | | |
> + * max paddr_end -->|-------| <--|-- svm->vm's phys_addr_end
> + * | ///// | |
> + * paddr5 --->| guard | |
> + * | page | |
> + * | ///// | |
> + * ------- <-/-- svm->vm->addr + svm->vm_size
> + *
> + * <1> If paddr == paddr1, then continue;
> + * <2> If paddr == paddr2~paddr4 and paddr_end > phys_addr_end,
> + * then continue;
> + * <3> if paddr >= paddr5 then continue;
> + */
> + vmoff = vm->phys_addr & ~PAGE_MASK;
> + phys_addr_end = vm->phys_addr + vm->size - PAGE_SIZE - vmoff;
> + paddr_end = paddr + size - offset;
> + if (__phys_to_pfn(vm->phys_addr) > __phys_to_pfn(paddr) ||
> + paddr_end - 1 > phys_addr_end - 1)
> continue;
>
> return svm;
> --
> 1.8.4
>
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