diff options
Diffstat (limited to 'include/asm-arm/pgtable.h')
| -rw-r--r-- | include/asm-arm/pgtable.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/asm-arm/pgtable.h b/include/asm-arm/pgtable.h index 2df4eacf4fa9..a9892eb42a23 100644 --- a/include/asm-arm/pgtable.h +++ b/include/asm-arm/pgtable.h @@ -17,6 +17,23 @@ #include <asm/arch/vmalloc.h> /* + * Just any arbitrary offset to the start of the vmalloc VM area: the + * current 8MB value just means that there will be a 8MB "hole" after the + * physical memory until the kernel virtual memory starts. That means that + * any out-of-bounds memory accesses will hopefully be caught. + * The vmalloc() routines leaves a hole of 4kB between each vmalloced + * area for the same reason. ;) + * + * Note that platforms may override VMALLOC_START, but they must provide + * VMALLOC_END. VMALLOC_END defines the (exclusive) limit of this space, + * which may not overlap IO space. + */ +#ifndef VMALLOC_START +#define VMALLOC_OFFSET (8*1024*1024) +#define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) +#endif + +/* * Hardware-wise, we have a two level page table structure, where the first * level has 4096 entries, and the second level has 256 entries. Each entry * is one 32-bit word. Most of the bits in the second level entry are used |