1 files changed, 122 insertions, 0 deletions
diff --git a/arch/tile/include/asm/pgalloc.h b/arch/tile/include/asm/pgalloc.h
new file mode 100644
index 00000000..e919c0bd
--- /dev/null
+++ b/arch/tile/include/asm/pgalloc.h
@@ -0,0 +1,122 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#ifndef _ASM_TILE_PGALLOC_H
+#define _ASM_TILE_PGALLOC_H
+
+#include <linux/threads.h>
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <asm/fixmap.h>
+#include <hv/hypervisor.h>
+
+/* Bits for the size of the second-level page table. */
+#define L2_KERNEL_PGTABLE_SHIFT \
+  (HV_LOG2_PAGE_SIZE_LARGE - HV_LOG2_PAGE_SIZE_SMALL + HV_LOG2_PTE_SIZE)
+
+/* We currently allocate user L2 page tables by page (unlike kernel L2s). */
+#if L2_KERNEL_PGTABLE_SHIFT < HV_LOG2_PAGE_SIZE_SMALL
+#define L2_USER_PGTABLE_SHIFT HV_LOG2_PAGE_SIZE_SMALL
+#else
+#define L2_USER_PGTABLE_SHIFT L2_KERNEL_PGTABLE_SHIFT
+#endif
+
+/* How many pages do we need, as an "order", for a user L2 page table? */
+#define L2_USER_PGTABLE_ORDER (L2_USER_PGTABLE_SHIFT - HV_LOG2_PAGE_SIZE_SMALL)
+
+/* How big is a kernel L2 page table? */
+#define L2_KERNEL_PGTABLE_SIZE (1 << L2_KERNEL_PGTABLE_SHIFT)
+
+static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
+{
+#ifdef CONFIG_64BIT
+	set_pte(pmdp, pmd);
+#else
+	set_pte(&pmdp->pud.pgd, pmd.pud.pgd);
+#endif
+}
+
+static inline void pmd_populate_kernel(struct mm_struct *mm,
+				       pmd_t *pmd, pte_t *ptep)
+{
+	set_pmd(pmd, ptfn_pmd(__pa(ptep) >> HV_LOG2_PAGE_TABLE_ALIGN,
+			      __pgprot(_PAGE_PRESENT)));
+}
+
+static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
+				pgtable_t page)
+{
+	set_pmd(pmd, ptfn_pmd(HV_PFN_TO_PTFN(page_to_pfn(page)),
+			      __pgprot(_PAGE_PRESENT)));
+}
+
+/*
+ * Allocate and free page tables.
+ */
+
+extern pgd_t *pgd_alloc(struct mm_struct *mm);
+extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
+
+extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address);
+extern void pte_free(struct mm_struct *mm, struct page *pte);
+
+#define pmd_pgtable(pmd) pmd_page(pmd)
+
+static inline pte_t *
+pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
+{
+	return pfn_to_kaddr(page_to_pfn(pte_alloc_one(mm, address)));
+}
+
+static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
+{
+	BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
+	pte_free(mm, virt_to_page(pte));
+}
+
+extern void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
+			   unsigned long address);
+
+#define check_pgt_cache()	do { } while (0)
+
+/*
+ * Get the small-page pte_t lowmem entry for a given pfn.
+ * This may or may not be in use, depending on whether the initial
+ * huge-page entry for the page has already been shattered.
+ */
+pte_t *get_prealloc_pte(unsigned long pfn);
+
+/* During init, we can shatter kernel huge pages if needed. */
+void shatter_pmd(pmd_t *pmd);
+
+/* After init, a more complex technique is required. */
+void shatter_huge_page(unsigned long addr);
+
+#ifdef __tilegx__
+/* We share a single page allocator for both L1 and L2 page tables. */
+#if HV_L1_SIZE != HV_L2_SIZE
+# error Rework assumption that L1 and L2 page tables are same size.
+#endif
+#define L1_USER_PGTABLE_ORDER L2_USER_PGTABLE_ORDER
+#define pud_populate(mm, pud, pmd) \
+  pmd_populate_kernel((mm), (pmd_t *)(pud), (pte_t *)(pmd))
+#define pmd_alloc_one(mm, addr) \
+  ((pmd_t *)page_to_virt(pte_alloc_one((mm), (addr))))
+#define pmd_free(mm, pmdp) \
+  pte_free((mm), virt_to_page(pmdp))
+#define __pmd_free_tlb(tlb, pmdp, address) \
+  __pte_free_tlb((tlb), virt_to_page(pmdp), (address))
+#endif
+
+#endif /* _ASM_TILE_PGALLOC_H */