Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 211 insertions, 0 deletions

diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c
new file mode 100644
index 0000000000..f8e9bc58a8
--- /dev/null
+++ b/arch/arm/mm/pgd.c
@@ -0,0 +1,211 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  linux/arch/arm/mm/pgd.c
+ *
+ *  Copyright (C) 1998-2005 Russell King
+ */
+#include <linux/mm.h>
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/slab.h>
+
+#include <asm/cp15.h>
+#include <asm/pgalloc.h>
+#include <asm/page.h>
+#include <asm/tlbflush.h>
+
+#include "mm.h"
+
+#ifdef CONFIG_ARM_LPAE
+#define __pgd_alloc()	kmalloc_array(PTRS_PER_PGD, sizeof(pgd_t), GFP_KERNEL)
+#define __pgd_free(pgd)	kfree(pgd)
+#else
+#define __pgd_alloc()	(pgd_t *)__get_free_pages(GFP_KERNEL, 2)
+#define __pgd_free(pgd)	free_pages((unsigned long)pgd, 2)
+#endif
+
+/*
+ * need to get a 16k page for level 1
+ */
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+	pgd_t *new_pgd, *init_pgd;
+	p4d_t *new_p4d, *init_p4d;
+	pud_t *new_pud, *init_pud;
+	pmd_t *new_pmd, *init_pmd;
+	pte_t *new_pte, *init_pte;
+
+	new_pgd = __pgd_alloc();
+	if (!new_pgd)
+		goto no_pgd;
+
+	memset(new_pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
+
+	/*
+	 * Copy over the kernel and IO PGD entries
+	 */
+	init_pgd = pgd_offset_k(0);
+	memcpy(new_pgd + USER_PTRS_PER_PGD, init_pgd + USER_PTRS_PER_PGD,
+		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+
+	clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));
+
+#ifdef CONFIG_ARM_LPAE
+	/*
+	 * Allocate PMD table for modules and pkmap mappings.
+	 */
+	new_p4d = p4d_alloc(mm, new_pgd + pgd_index(MODULES_VADDR),
+			    MODULES_VADDR);
+	if (!new_p4d)
+		goto no_p4d;
+
+	new_pud = pud_alloc(mm, new_p4d, MODULES_VADDR);
+	if (!new_pud)
+		goto no_pud;
+
+	new_pmd = pmd_alloc(mm, new_pud, 0);
+	if (!new_pmd)
+		goto no_pmd;
+#ifdef CONFIG_KASAN
+	/*
+	 * Copy PMD table for KASAN shadow mappings.
+	 */
+	init_pgd = pgd_offset_k(TASK_SIZE);
+	init_p4d = p4d_offset(init_pgd, TASK_SIZE);
+	init_pud = pud_offset(init_p4d, TASK_SIZE);
+	init_pmd = pmd_offset(init_pud, TASK_SIZE);
+	new_pmd = pmd_offset(new_pud, TASK_SIZE);
+	memcpy(new_pmd, init_pmd,
+	       (pmd_index(MODULES_VADDR) - pmd_index(TASK_SIZE))
+	       * sizeof(pmd_t));
+	clean_dcache_area(new_pmd, PTRS_PER_PMD * sizeof(pmd_t));
+#endif /* CONFIG_KASAN */
+#endif /* CONFIG_LPAE */
+
+	if (!vectors_high()) {
+		/*
+		 * On ARM, first page must always be allocated since it
+		 * contains the machine vectors. The vectors are always high
+		 * with LPAE.
+		 */
+		new_p4d = p4d_alloc(mm, new_pgd, 0);
+		if (!new_p4d)
+			goto no_p4d;
+
+		new_pud = pud_alloc(mm, new_p4d, 0);
+		if (!new_pud)
+			goto no_pud;
+
+		new_pmd = pmd_alloc(mm, new_pud, 0);
+		if (!new_pmd)
+			goto no_pmd;
+
+		new_pte = pte_alloc_map(mm, new_pmd, 0);
+		if (!new_pte)
+			goto no_pte;
+
+#ifndef CONFIG_ARM_LPAE
+		/*
+		 * Modify the PTE pointer to have the correct domain.  This
+		 * needs to be the vectors domain to avoid the low vectors
+		 * being unmapped.
+		 */
+		pmd_val(*new_pmd) &= ~PMD_DOMAIN_MASK;
+		pmd_val(*new_pmd) |= PMD_DOMAIN(DOMAIN_VECTORS);
+#endif
+
+		init_p4d = p4d_offset(init_pgd, 0);
+		init_pud = pud_offset(init_p4d, 0);
+		init_pmd = pmd_offset(init_pud, 0);
+		init_pte = pte_offset_map(init_pmd, 0);
+		set_pte_ext(new_pte + 0, init_pte[0], 0);
+		set_pte_ext(new_pte + 1, init_pte[1], 0);
+		pte_unmap(init_pte);
+		pte_unmap(new_pte);
+	}
+
+	return new_pgd;
+
+no_pte:
+	pmd_free(mm, new_pmd);
+	mm_dec_nr_pmds(mm);
+no_pmd:
+	pud_free(mm, new_pud);
+no_pud:
+	p4d_free(mm, new_p4d);
+no_p4d:
+	__pgd_free(new_pgd);
+no_pgd:
+	return NULL;
+}
+
+void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
+{
+	pgd_t *pgd;
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
+	pgtable_t pte;
+
+	if (!pgd_base)
+		return;
+
+	pgd = pgd_base + pgd_index(0);
+	if (pgd_none_or_clear_bad(pgd))
+		goto no_pgd;
+
+	p4d = p4d_offset(pgd, 0);
+	if (p4d_none_or_clear_bad(p4d))
+		goto no_p4d;
+
+	pud = pud_offset(p4d, 0);
+	if (pud_none_or_clear_bad(pud))
+		goto no_pud;
+
+	pmd = pmd_offset(pud, 0);
+	if (pmd_none_or_clear_bad(pmd))
+		goto no_pmd;
+
+	pte = pmd_pgtable(*pmd);
+	pmd_clear(pmd);
+	pte_free(mm, pte);
+	mm_dec_nr_ptes(mm);
+no_pmd:
+	pud_clear(pud);
+	pmd_free(mm, pmd);
+	mm_dec_nr_pmds(mm);
+no_pud:
+	p4d_clear(p4d);
+	pud_free(mm, pud);
+no_p4d:
+	pgd_clear(pgd);
+	p4d_free(mm, p4d);
+no_pgd:
+#ifdef CONFIG_ARM_LPAE
+	/*
+	 * Free modules/pkmap or identity pmd tables.
+	 */
+	for (pgd = pgd_base; pgd < pgd_base + PTRS_PER_PGD; pgd++) {
+		if (pgd_none_or_clear_bad(pgd))
+			continue;
+		if (pgd_val(*pgd) & L_PGD_SWAPPER)
+			continue;
+		p4d = p4d_offset(pgd, 0);
+		if (p4d_none_or_clear_bad(p4d))
+			continue;
+		pud = pud_offset(p4d, 0);
+		if (pud_none_or_clear_bad(pud))
+			continue;
+		pmd = pmd_offset(pud, 0);
+		pud_clear(pud);
+		pmd_free(mm, pmd);
+		mm_dec_nr_pmds(mm);
+		p4d_clear(p4d);
+		pud_free(mm, pud);
+		mm_dec_nr_puds(mm);
+		pgd_clear(pgd);
+		p4d_free(mm, p4d);
+	}
+#endif
+	__pgd_free(pgd_base);
+}