Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932755AbaJ2Liq (ORCPT ); Wed, 29 Oct 2014 07:38:46 -0400 Received: from mail-pd0-f171.google.com ([209.85.192.171]:42297 "EHLO mail-pd0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932461AbaJ2Lip (ORCPT ); Wed, 29 Oct 2014 07:38:45 -0400 From: Minfei Huang To: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, pbonzini@redhat.com, akpm@linux-foundation.org, bp@suse.de Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Minfei Huang Subject: [PATCH v2] x86/mm: Re-use the early_ioremap fixed area Date: Wed, 29 Oct 2014 19:38:37 +0800 Message-Id: <1414582717-32729-1-git-send-email-mnfhuang@gmail.com> X-Mailer: git-send-email 1.8.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The temp fixed area is only used during boot for early_ioremap(), and it is unused when the ioremap() is functional. vmalloc/pkmap area become available after early boot so the temp fixed area is available for re-use. The virtual address is more precious on i386, especially turning on the high memory. So we can re-use the virtual address whichever we can. The macros of FIXADDR_BOOT_START and FIXADDR_BOOT_SIZE donot use any more. Signed-off-by: Minfei Huang --- arch/x86/include/asm/fixmap.h | 2 -- arch/x86/include/asm/highmem.h | 25 ++++++++++++++----------- arch/x86/include/asm/pgtable_32_types.h | 4 ++-- 3 files changed, 16 insertions(+), 15 deletions(-) diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h index ffb1733..bf728e4 100644 --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -136,9 +136,7 @@ enum fixed_addresses { extern void reserve_top_address(unsigned long reserve); #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) -#define FIXADDR_BOOT_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) -#define FIXADDR_BOOT_START (FIXADDR_TOP - FIXADDR_BOOT_SIZE) extern int fixmaps_set; diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h index 302a323..fa0713d 100644 --- a/arch/x86/include/asm/highmem.h +++ b/arch/x86/include/asm/highmem.h @@ -38,17 +38,20 @@ extern unsigned long highstart_pfn, highend_pfn; /* * Ordering is: * - * FIXADDR_TOP - * fixed_addresses - * FIXADDR_START - * temp fixed addresses - * FIXADDR_BOOT_START - * Persistent kmap area - * PKMAP_BASE - * VMALLOC_END - * Vmalloc area - * VMALLOC_START - * high_memory + * high memory on: high_memory off: + * FIXADDR_TOP FIXADDR_TOP + * fixed addresses fixed addresses + * FIXADDR_START FIXADDR_START + * temp fixed addresses/persistent kmap area VMALLOC_END + * PKMAP_BASE temp fixed addresses/vmalloc area + * VMALLOC_END VMALLOC_START + * vmalloc area high_memory + * VMALLOC_START + * high_memory + * + * The temp fixed area is only used during boot for early_ioremap(), and + * it is unused when the ioremap() is functional. vmalloc/pkmap area become + * available after early boot so the temp fixed area is available for re-use. */ #define LAST_PKMAP_MASK (LAST_PKMAP-1) #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm/pgtable_32_types.h index 2ac5fc8..9fb2f2b 100644 --- a/arch/x86/include/asm/pgtable_32_types.h +++ b/arch/x86/include/asm/pgtable_32_types.h @@ -37,13 +37,13 @@ extern bool __vmalloc_start_set; /* set once high_memory is set */ #define LAST_PKMAP 1024 #endif -#define PKMAP_BASE ((FIXADDR_BOOT_START - PAGE_SIZE * (LAST_PKMAP + 1)) \ +#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE * (LAST_PKMAP + 1)) \ & PMD_MASK) #ifdef CONFIG_HIGHMEM # define VMALLOC_END (PKMAP_BASE - 2 * PAGE_SIZE) #else -# define VMALLOC_END (FIXADDR_BOOT_START - 2 * PAGE_SIZE) +# define VMALLOC_END (FIXADDR_START - 2 * PAGE_SIZE) #endif #define MODULES_VADDR VMALLOC_START -- 1.8.3.1 -- 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/