From 63e7b6d90c1ebdb73d82eedb945b62ceedc3f963 Mon Sep 17 00:00:00 2001 From: Minfei Huang Date: Wed, 29 Oct 2014 19:38:37 +0800 Subject: [PATCH] x86: mm: Re-use the early_ioremap fixed area The temp fixed area is only used during boot for early_ioremap(), and it is unused when 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 high memory. So we can re-use the virtual address space. Remove the now unused defines FIXADDR_BOOT_START and FIXADDR_BOOT_SIZE. Signed-off-by: Minfei Huang Cc: pbonzini@redhat.com Cc: bp@suse.de Link: http://lkml.kernel.org/r/1414582717-32729-1-git-send-email-mnfhuang@gmail.com Signed-off-by: Thomas Gleixner --- 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 ffb1733ac91f..bf728e49c53c 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 302a323b3f67..04e9d023168f 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 2ac5fc86abb3..9fb2f2bc8245 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 -- 2.39.2