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authorAl Viro <viro@zeniv.linux.org.uk>2008-08-18 03:05:42 +0200
committerH. Peter Anvin <hpa@zytor.com>2008-10-23 07:55:20 +0200
commitbb8985586b7a906e116db835c64773b7a7d51663 (patch)
treede93ae58e88cc563d95cc124a73f3930594c6100 /arch/x86/include/asm/sparsemem.h
parentx86, um: initial part of asm-um move (diff)
downloadlinux-bb8985586b7a906e116db835c64773b7a7d51663.tar.xz
linux-bb8985586b7a906e116db835c64773b7a7d51663.zip
x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'arch/x86/include/asm/sparsemem.h')
-rw-r--r--arch/x86/include/asm/sparsemem.h34
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/x86/include/asm/sparsemem.h b/arch/x86/include/asm/sparsemem.h
new file mode 100644
index 000000000000..38f8e6bc3186
--- /dev/null
+++ b/arch/x86/include/asm/sparsemem.h
@@ -0,0 +1,34 @@
+#ifndef ASM_X86__SPARSEMEM_H
+#define ASM_X86__SPARSEMEM_H
+
+#ifdef CONFIG_SPARSEMEM
+/*
+ * generic non-linear memory support:
+ *
+ * 1) we will not split memory into more chunks than will fit into the flags
+ * field of the struct page
+ *
+ * SECTION_SIZE_BITS 2^n: size of each section
+ * MAX_PHYSADDR_BITS 2^n: max size of physical address space
+ * MAX_PHYSMEM_BITS 2^n: how much memory we can have in that space
+ *
+ */
+
+#ifdef CONFIG_X86_32
+# ifdef CONFIG_X86_PAE
+# define SECTION_SIZE_BITS 29
+# define MAX_PHYSADDR_BITS 36
+# define MAX_PHYSMEM_BITS 36
+# else
+# define SECTION_SIZE_BITS 26
+# define MAX_PHYSADDR_BITS 32
+# define MAX_PHYSMEM_BITS 32
+# endif
+#else /* CONFIG_X86_32 */
+# define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */
+# define MAX_PHYSADDR_BITS 44
+# define MAX_PHYSMEM_BITS 44
+#endif
+
+#endif /* CONFIG_SPARSEMEM */
+#endif /* ASM_X86__SPARSEMEM_H */