OpenRISC: Memory management

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 102 insertions, 0 deletions

diff --git a/arch/openrisc/include/asm/pgalloc.h b/arch/openrisc/include/asm/pgalloc.h
new file mode 100644
index 00000000000..05c39ecd2ef
--- /dev/null
+++ b/arch/openrisc/include/asm/pgalloc.h
@@ -0,0 +1,102 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_OPENRISC_PGALLOC_H
+#define __ASM_OPENRISC_PGALLOC_H
+
+#include <asm/page.h>
+#include <linux/threads.h>
+#include <linux/mm.h>
+#include <linux/memblock.h>
+#include <linux/bootmem.h>
+
+extern int mem_init_done;
+
+#define pmd_populate_kernel(mm, pmd, pte) \
+        set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte)))
+
+static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
+                                struct page *pte)
+{
+        set_pmd(pmd, __pmd(_KERNPG_TABLE +
+                     ((unsigned long)page_to_pfn(pte) <<
+                     (unsigned long) PAGE_SHIFT)));
+}
+
+/*
+ * Allocate and free page tables.
+ */
+static inline pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+        pgd_t *ret = (pgd_t *)__get_free_page(GFP_KERNEL);
+
+        if (ret) {
+                memset(ret, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
+                memcpy(ret + USER_PTRS_PER_PGD,
+                       swapper_pg_dir + USER_PTRS_PER_PGD,
+                       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+
+        }
+        return ret;
+}
+
+#if 0
+/* FIXME: This seems to be the preferred style, but we are using
+ * current_pgd (from mm->pgd) to load kernel pages so we need it
+ * initialized.  This needs to be looked into.
+ */
+extern inline pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+        return (pgd_t *)get_zeroed_page(GFP_KERNEL);
+}
+#endif
+
+static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+        free_page((unsigned long)pgd);
+}
+
+extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address);
+
+static inline struct page *pte_alloc_one(struct mm_struct *mm,
+                                         unsigned long address)
+{
+        struct page *pte;
+        pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0);
+        if (pte)
+                clear_page(page_address(pte));
+        return pte;
+}
+
+static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
+{
+        free_page((unsigned long)pte);
+}
+
+static inline void pte_free(struct mm_struct *mm, struct page *pte)
+{
+        __free_page(pte);
+}
+
+
+#define __pte_free_tlb(tlb, pte, addr) tlb_remove_page((tlb), (pte))
+#define pmd_pgtable(pmd) pmd_page(pmd)
+
+#define check_pgt_cache()          do { } while (0)
+
+#endif