Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751789Ab2JIEkH (ORCPT ); Tue, 9 Oct 2012 00:40:07 -0400 Received: from rcsinet15.oracle.com ([148.87.113.117]:36613 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751960Ab2JIEkB (ORCPT ); Tue, 9 Oct 2012 00:40:01 -0400 From: Yinghai Lu To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Jacob Shin , Tejun Heo Cc: Stefano Stabellini , linux-kernel@vger.kernel.org, Yinghai Lu Subject: [PATCH 03/10] x86, mm: get early page table from BRK Date: Mon, 8 Oct 2012 21:39:11 -0700 Message-Id: <1349757558-10856-4-git-send-email-yinghai@kernel.org> X-Mailer: git-send-email 1.7.7 In-Reply-To: <1349757558-10856-1-git-send-email-yinghai@kernel.org> References: <1349757558-10856-1-git-send-email-yinghai@kernel.org> X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3331 Lines: 99 Get pgt_buf early from BRK, and use it to map page table at first. also use the left at first, then use new one. -v2: extra xen call back for that new range. -v3: fix compiling about #llx in print out that is reported by Fengguang -v4: remove the early_pgt_buf_* stuff, because xen interface is ready yet. still need to run x86_init.mapping.pagetable_reserve separately. so we will waste some pages in BRK, will address that later. Signed-off-by: Yinghai Lu --- arch/x86/include/asm/pgtable.h | 1 + arch/x86/kernel/setup.c | 2 ++ arch/x86/mm/init.c | 26 +++++++++++++++++++++++++- 3 files changed, 28 insertions(+), 1 deletions(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 52d40a1..25fa5bb 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -599,6 +599,7 @@ static inline int pgd_none(pgd_t pgd) extern int direct_gbpages; void init_mem_mapping(void); +void early_alloc_pgt_buf(void); /* local pte updates need not use xchg for locking */ static inline pte_t native_local_ptep_get_and_clear(pte_t *ptep) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 4989f80..7eb6855 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -896,6 +896,8 @@ void __init setup_arch(char **cmdline_p) reserve_ibft_region(); + early_alloc_pgt_buf(); + /* * Need to conclude brk, before memblock_x86_fill() * it could use memblock_find_in_range, could overlap with diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 0c58f2d..a89f485 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -317,12 +317,22 @@ static void __init find_early_table_space(unsigned long start, unsigned long good_end, unsigned long tables) { - phys_addr_t base; + unsigned long base; base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE); if (!base) panic("Cannot find space for the kernel page tables"); + init_memory_mapping(base, base + tables); + if (pgt_buf_end > pgt_buf_start) { + printk(KERN_DEBUG "kernel direct mapping tables from %#lx to %#lx @ [mem %#010lx-%#010lx]\n", + base, base + tables - 1, pgt_buf_start << PAGE_SHIFT, + (pgt_buf_end << PAGE_SHIFT) - 1); + + x86_init.mapping.pagetable_reserve(PFN_PHYS(pgt_buf_start), + PFN_PHYS(pgt_buf_end)); + } + pgt_buf_start = base >> PAGE_SHIFT; pgt_buf_end = pgt_buf_start; pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT); @@ -469,6 +479,20 @@ void __init init_mem_mapping(void) early_memtest(0, max_pfn_mapped << PAGE_SHIFT); } +RESERVE_BRK(early_pgt_alloc, 16384); + +void __init early_alloc_pgt_buf(void) +{ + unsigned long tables = 16384; + phys_addr_t base; + + base = __pa(extend_brk(tables, PAGE_SIZE)); + + pgt_buf_start = base >> PAGE_SHIFT; + pgt_buf_end = pgt_buf_start; + pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT); +} + /* * devmem_is_allowed() checks to see if /dev/mem access to a certain address * is valid. The argument is a physical page number. -- 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/