From 32df75cd148b43e007848ddbfdb1ea25535114cb Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 31 Dec 2013 12:37:52 -0500 Subject: [PATCH] xen/mmu/p2m: Refactor the xen_pagetable_init code (v2). The revectoring and copying of the P2M only happens when !auto-xlat and on 64-bit builds. It is not obvious from the code, so lets have seperate 32 and 64-bit functions. We also invert the check for auto-xlat to make the code flow simpler. Suggested-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/mmu.c | 70 ++++++++++++++++++++++++---------------------- 1 file changed, 37 insertions(+), 33 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index ce563be09cc1..c140efffe37e 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1198,44 +1198,40 @@ static void __init xen_cleanhighmap(unsigned long vaddr, * instead of somewhere later and be confusing. */ xen_mc_flush(); } -#endif -static void __init xen_pagetable_init(void) +static void __init xen_pagetable_p2m_copy(void) { -#ifdef CONFIG_X86_64 unsigned long size; unsigned long addr; -#endif - paging_init(); - xen_setup_shared_info(); -#ifdef CONFIG_X86_64 - if (!xen_feature(XENFEAT_auto_translated_physmap)) { - unsigned long new_mfn_list; + unsigned long new_mfn_list; + + if (xen_feature(XENFEAT_auto_translated_physmap)) + return; + + 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 + return; - /* 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 - goto skip; - } /* 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 @@ -1255,7 +1251,15 @@ static void __init xen_pagetable_init(void) * anything at this stage. */ xen_cleanhighmap(MODULES_VADDR, roundup(MODULES_VADDR, PUD_SIZE) - 1); #endif -skip: +} +#endif + +static void __init xen_pagetable_init(void) +{ + paging_init(); + xen_setup_shared_info(); +#ifdef CONFIG_X86_64 + xen_pagetable_p2m_copy(); #endif xen_post_allocator_init(); } -- GitLab