Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755342Ab2KMQxB (ORCPT ); Tue, 13 Nov 2012 11:53:01 -0500 Received: from smtp.citrix.com ([66.165.176.89]:25264 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755282Ab2KMQw7 (ORCPT ); Tue, 13 Nov 2012 11:52:59 -0500 X-IronPort-AV: E=Sophos;i="4.80,768,1344211200"; d="scan'208";a="44442760" Date: Tue, 13 Nov 2012 16:52:25 +0000 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Yinghai Lu CC: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Jacob Shin , Andrew Morton , Stefano Stabellini , Konrad Rzeszutek Wilk , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 22/46] x86, mm: Remove early_memremap workaround for page table accessing on 64bit In-Reply-To: <1352755122-25660-23-git-send-email-yinghai@kernel.org> Message-ID: References: <20121112193044.GA11615@phenom.dumpdata.com> <1352755122-25660-1-git-send-email-yinghai@kernel.org> <1352755122-25660-23-git-send-email-yinghai@kernel.org> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4125 Lines: 127 On Mon, 12 Nov 2012, Yinghai Lu wrote: > We try to put page table high to make room for kdump, and at that time > those ranges are not mapped yet, and have to use ioremap to access it. > > Now after patch that pre-map page table top down. > x86, mm: setup page table in top-down > We do not need that workaround anymore. > > Just use __va to return directly mapping address. > > Signed-off-by: Yinghai Lu Acked-by: Stefano Stabellini > arch/x86/mm/init_64.c | 38 ++++---------------------------------- > 1 files changed, 4 insertions(+), 34 deletions(-) > > diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c > index eefaea6..5ee9242 100644 > --- a/arch/x86/mm/init_64.c > +++ b/arch/x86/mm/init_64.c > @@ -340,36 +340,12 @@ static __ref void *alloc_low_page(unsigned long *phys) > } else > pfn = pgt_buf_end++; > > - adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE); > + adr = __va(pfn * PAGE_SIZE); > clear_page(adr); > *phys = pfn * PAGE_SIZE; > return adr; > } > > -static __ref void *map_low_page(void *virt) > -{ > - void *adr; > - unsigned long phys, left; > - > - if (after_bootmem) > - return virt; > - > - phys = __pa(virt); > - left = phys & (PAGE_SIZE - 1); > - adr = early_memremap(phys & PAGE_MASK, PAGE_SIZE); > - adr = (void *)(((unsigned long)adr) | left); > - > - return adr; > -} > - > -static __ref void unmap_low_page(void *adr) > -{ > - if (after_bootmem) > - return; > - > - early_iounmap((void *)((unsigned long)adr & PAGE_MASK), PAGE_SIZE); > -} > - > static unsigned long __meminit > phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end, > pgprot_t prot) > @@ -442,10 +418,9 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, > if (pmd_val(*pmd)) { > if (!pmd_large(*pmd)) { > spin_lock(&init_mm.page_table_lock); > - pte = map_low_page((pte_t *)pmd_page_vaddr(*pmd)); > + pte = (pte_t *)pmd_page_vaddr(*pmd); > last_map_addr = phys_pte_init(pte, address, > end, prot); > - unmap_low_page(pte); > spin_unlock(&init_mm.page_table_lock); > continue; > } > @@ -483,7 +458,6 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, > > pte = alloc_low_page(&pte_phys); > last_map_addr = phys_pte_init(pte, address, end, new_prot); > - unmap_low_page(pte); > > spin_lock(&init_mm.page_table_lock); > pmd_populate_kernel(&init_mm, pmd, __va(pte_phys)); > @@ -518,10 +492,9 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, > > if (pud_val(*pud)) { > if (!pud_large(*pud)) { > - pmd = map_low_page(pmd_offset(pud, 0)); > + pmd = pmd_offset(pud, 0); > last_map_addr = phys_pmd_init(pmd, addr, end, > page_size_mask, prot); > - unmap_low_page(pmd); > __flush_tlb_all(); > continue; > } > @@ -560,7 +533,6 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, > pmd = alloc_low_page(&pmd_phys); > last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask, > prot); > - unmap_low_page(pmd); > > spin_lock(&init_mm.page_table_lock); > pud_populate(&init_mm, pud, __va(pmd_phys)); > @@ -596,17 +568,15 @@ kernel_physical_mapping_init(unsigned long start, > next = end; > > if (pgd_val(*pgd)) { > - pud = map_low_page((pud_t *)pgd_page_vaddr(*pgd)); > + pud = (pud_t *)pgd_page_vaddr(*pgd); > last_map_addr = phys_pud_init(pud, __pa(start), > __pa(end), page_size_mask); > - unmap_low_page(pud); > continue; > } > > pud = alloc_low_page(&pud_phys); > last_map_addr = phys_pud_init(pud, __pa(start), __pa(next), > page_size_mask); > - unmap_low_page(pud); > > spin_lock(&init_mm.page_table_lock); > pgd_populate(&init_mm, pgd, __va(pud_phys)); > -- > 1.7.7 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/