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Diffstat (limited to 'arch/powerpc/include/asm/pte-hash64.h')
-rw-r--r--arch/powerpc/include/asm/pte-hash64.h54
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diff --git a/arch/powerpc/include/asm/pte-hash64.h b/arch/powerpc/include/asm/pte-hash64.h
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+#ifndef _ASM_POWERPC_PTE_HASH64_H
+#define _ASM_POWERPC_PTE_HASH64_H
+#ifdef __KERNEL__
+
+/*
+ * Common bits between 4K and 64K pages in a linux-style PTE.
+ * These match the bits in the (hardware-defined) PowerPC PTE as closely
+ * as possible. Additional bits may be defined in pgtable-hash64-*.h
+ *
+ * Note: We only support user read/write permissions. Supervisor always
+ * have full read/write to pages above PAGE_OFFSET (pages below that
+ * always use the user access permissions).
+ *
+ * We could create separate kernel read-only if we used the 3 PP bits
+ * combinations that newer processors provide but we currently don't.
+ */
+#define _PAGE_PRESENT 0x0001 /* software: pte contains a translation */
+#define _PAGE_USER 0x0002 /* matches one of the PP bits */
+#define _PAGE_FILE 0x0002 /* (!present only) software: pte holds file offset */
+#define _PAGE_EXEC 0x0004 /* No execute on POWER4 and newer (we invert) */
+#define _PAGE_GUARDED 0x0008
+#define _PAGE_COHERENT 0x0010 /* M: enforce memory coherence (SMP systems) */
+#define _PAGE_NO_CACHE 0x0020 /* I: cache inhibit */
+#define _PAGE_WRITETHRU 0x0040 /* W: cache write-through */
+#define _PAGE_DIRTY 0x0080 /* C: page changed */
+#define _PAGE_ACCESSED 0x0100 /* R: page referenced */
+#define _PAGE_RW 0x0200 /* software: user write access allowed */
+#define _PAGE_BUSY 0x0800 /* software: PTE & hash are busy */
+
+/* No separate kernel read-only */
+#define _PAGE_KERNEL_RW (_PAGE_RW | _PAGE_DIRTY) /* user access blocked by key */
+#define _PAGE_KERNEL_RO _PAGE_KERNEL_RW
+
+/* Strong Access Ordering */
+#define _PAGE_SAO (_PAGE_WRITETHRU | _PAGE_NO_CACHE | _PAGE_COHERENT)
+
+/* No page size encoding in the linux PTE */
+#define _PAGE_PSIZE 0
+
+/* PTEIDX nibble */
+#define _PTEIDX_SECONDARY 0x8
+#define _PTEIDX_GROUP_IX 0x7
+
+/* Hash table based platforms need atomic updates of the linux PTE */
+#define PTE_ATOMIC_UPDATES 1
+
+#ifdef CONFIG_PPC_64K_PAGES
+#include <asm/pte-hash64-64k.h>
+#else
+#include <asm/pte-hash64-4k.h>
+#endif
+
+#endif /* __KERNEL__ */
+#endif /* _ASM_POWERPC_PTE_HASH64_H */