From b621e157ba48fb7d36945405de68c5fa25e7b73c Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 3 Jan 2014 14:08:39 -0500 Subject: [PATCH] xen/mmu: Cleanup xen_pagetable_p2m_copy a bit. Stefano noticed that the code runs only under 64-bit so the comments about 32-bit are pointless. Also we change the condition for xen_revector_p2m_tree returning the same value (because it could not allocate a swath of space to put the new P2M in) or it had been called once already. In such we return early from the function. Signed-off-by: Konrad Rzeszutek Wilk Acked-by: Stefano Stabellini --- arch/x86/xen/mmu.c | 40 ++++++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 20 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index c140eff..9d74249 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1209,29 +1209,29 @@ static void __init xen_pagetable_p2m_copy(void) size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long)); - /* On 32-bit, we get zero so this never gets executed. */ new_mfn_list = xen_revector_p2m_tree(); - if (new_mfn_list && new_mfn_list != xen_start_info->mfn_list) { - /* using __ka address and sticking INVALID_P2M_ENTRY! */ - memset((void *)xen_start_info->mfn_list, 0xff, size); - - /* We should be in __ka space. */ - BUG_ON(xen_start_info->mfn_list < __START_KERNEL_map); - addr = xen_start_info->mfn_list; - /* We roundup to the PMD, which means that if anybody at this stage is - * using the __ka address of xen_start_info or xen_start_info->shared_info - * they are in going to crash. Fortunatly we have already revectored - * in xen_setup_kernel_pagetable and in xen_setup_shared_info. */ - size = roundup(size, PMD_SIZE); - xen_cleanhighmap(addr, addr + size); - - size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long)); - memblock_free(__pa(xen_start_info->mfn_list), size); - /* And revector! Bye bye old array */ - xen_start_info->mfn_list = new_mfn_list; - } else + /* No memory or already called. */ + if (!new_mfn_list || new_mfn_list == xen_start_info->mfn_list) return; + /* using __ka address and sticking INVALID_P2M_ENTRY! */ + memset((void *)xen_start_info->mfn_list, 0xff, size); + + /* We should be in __ka space. */ + BUG_ON(xen_start_info->mfn_list < __START_KERNEL_map); + addr = xen_start_info->mfn_list; + /* We roundup to the PMD, which means that if anybody at this stage is + * using the __ka address of xen_start_info or xen_start_info->shared_info + * they are in going to crash. Fortunatly we have already revectored + * in xen_setup_kernel_pagetable and in xen_setup_shared_info. */ + size = roundup(size, PMD_SIZE); + xen_cleanhighmap(addr, addr + size); + + size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long)); + memblock_free(__pa(xen_start_info->mfn_list), size); + /* And revector! Bye bye old array */ + xen_start_info->mfn_list = new_mfn_list; + /* At this stage, cleanup_highmap has already cleaned __ka space * from _brk_limit way up to the max_pfn_mapped (which is the end of * the ramdisk). We continue on, erasing PMD entries that point to page -- 2.7.4