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-rw-r--r--arch/arc/include/asm/pgalloc.h97
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diff --git a/arch/arc/include/asm/pgalloc.h b/arch/arc/include/asm/pgalloc.h
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * vineetg: June 2011
+ * -"/proc/meminfo | grep PageTables" kept on increasing
+ * Recently added pgtable dtor was not getting called.
+ *
+ * vineetg: May 2011
+ * -Variable pg-sz means that Page Tables could be variable sized themselves
+ * So calculate it based on addr traversal split [pgd-bits:pte-bits:xxx]
+ * -Page Table size capped to max 1 to save memory - hence verified.
+ * -Since these deal with constants, gcc compile-time optimizes them.
+ *
+ * vineetg: Nov 2010
+ * -Added pgtable ctor/dtor used for pgtable mem accounting
+ *
+ * vineetg: April 2010
+ * -Switched pgtable_t from being struct page * to unsigned long
+ * =Needed so that Page Table allocator (pte_alloc_one) is not forced to
+ * deal with struct page. That way in future we can make it allocate
+ * multiple PG Tbls in one Page Frame
+ * =sweet side effect is avoiding calls to ugly page_address( ) from the
+ * pg-tlb allocator sub-sys (pte_alloc_one, ptr_free, pmd_populate)
+ *
+ * Amit Bhor, Sameer Dhavale: Codito Technologies 2004
+ */
+
+#ifndef _ASM_ARC_PGALLOC_H
+#define _ASM_ARC_PGALLOC_H
+
+#include <linux/mm.h>
+#include <linux/log2.h>
+#include <asm-generic/pgalloc.h>
+
+static inline void
+pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
+{
+ /*
+ * The cast to long below is OK in 32-bit PAE40 regime with long long pte
+ * Despite "wider" pte, the pte table needs to be in non-PAE low memory
+ * as all higher levels can only hold long pointers.
+ *
+ * The cast itself is needed given simplistic definition of set_pmd()
+ */
+ set_pmd(pmd, __pmd((unsigned long)pte));
+}
+
+static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t pte_page)
+{
+ set_pmd(pmd, __pmd((unsigned long)page_address(pte_page)));
+}
+
+static inline pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+ pgd_t *ret = (pgd_t *) __get_free_page(GFP_KERNEL);
+
+ if (ret) {
+ int num, num2;
+ num = USER_PTRS_PER_PGD + USER_KERNEL_GUTTER / PGDIR_SIZE;
+ memzero(ret, num * sizeof(pgd_t));
+
+ num2 = VMALLOC_SIZE / PGDIR_SIZE;
+ memcpy(ret + num, swapper_pg_dir + num, num2 * sizeof(pgd_t));
+
+ memzero(ret + num + num2,
+ (PTRS_PER_PGD - num - num2) * sizeof(pgd_t));
+
+ }
+ return ret;
+}
+
+#if CONFIG_PGTABLE_LEVELS > 3
+
+static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4dp, pud_t *pudp)
+{
+ set_p4d(p4dp, __p4d((unsigned long)pudp));
+}
+
+#define __pud_free_tlb(tlb, pmd, addr) pud_free((tlb)->mm, pmd)
+
+#endif
+
+#if CONFIG_PGTABLE_LEVELS > 2
+
+static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmdp)
+{
+ set_pud(pudp, __pud((unsigned long)pmdp));
+}
+
+#define __pmd_free_tlb(tlb, pmd, addr) pmd_free((tlb)->mm, pmd)
+
+#endif
+
+#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte)
+
+#endif /* _ASM_ARC_PGALLOC_H */