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| author | Minfei Huang <mnfhuang@gmail.com> | 2014-10-29 14:38:37 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2014-11-03 15:40:44 +0300 |
| commit | 63e7b6d90c1ebdb73d82eedb945b62ceedc3f963 (patch) | |
| tree | b70608ec34780769c93d7a3d261d625999be6327 /arch/x86/include/asm/highmem.h | |
| parent | 96e70f83285676d8794f62f3c294d0247bef6b21 (diff) | |
| download | linux-63e7b6d90c1ebdb73d82eedb945b62ceedc3f963.tar.xz | |
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 <mnfhuang@gmail.com>
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 <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/include/asm/highmem.h')
| -rw-r--r-- | arch/x86/include/asm/highmem.h | 25 |
1 files changed, 14 insertions, 11 deletions
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) |