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-rw-r--r--arch/powerpc/mm/init-common.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c
new file mode 100644
index 0000000000..119ef491f7
--- /dev/null
+++ b/arch/powerpc/mm/init-common.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PowerPC version
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ * and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ * Copyright (C) 1996 Paul Mackerras
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * Dave Engebretsen <engebret@us.ibm.com>
+ * Rework for PPC64 port.
+ */
+
+#undef DEBUG
+
+#include <linux/string.h>
+#include <linux/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/kup.h>
+#include <asm/smp.h>
+
+phys_addr_t memstart_addr __ro_after_init = (phys_addr_t)~0ull;
+EXPORT_SYMBOL_GPL(memstart_addr);
+phys_addr_t kernstart_addr __ro_after_init;
+EXPORT_SYMBOL_GPL(kernstart_addr);
+unsigned long kernstart_virt_addr __ro_after_init = KERNELBASE;
+EXPORT_SYMBOL_GPL(kernstart_virt_addr);
+
+bool disable_kuep = !IS_ENABLED(CONFIG_PPC_KUEP);
+bool disable_kuap = !IS_ENABLED(CONFIG_PPC_KUAP);
+
+static int __init parse_nosmep(char *p)
+{
+ if (!IS_ENABLED(CONFIG_PPC_BOOK3S_64))
+ return 0;
+
+ disable_kuep = true;
+ pr_warn("Disabling Kernel Userspace Execution Prevention\n");
+ return 0;
+}
+early_param("nosmep", parse_nosmep);
+
+static int __init parse_nosmap(char *p)
+{
+ disable_kuap = true;
+ pr_warn("Disabling Kernel Userspace Access Protection\n");
+ return 0;
+}
+early_param("nosmap", parse_nosmap);
+
+void __weak setup_kuep(bool disabled)
+{
+ if (!IS_ENABLED(CONFIG_PPC_KUEP) || disabled)
+ return;
+
+ if (smp_processor_id() != boot_cpuid)
+ return;
+
+ pr_info("Activating Kernel Userspace Execution Prevention\n");
+}
+
+void setup_kup(void)
+{
+ setup_kuap(disable_kuap);
+ setup_kuep(disable_kuep);
+}
+
+#define CTOR(shift) static void ctor_##shift(void *addr) \
+{ \
+ memset(addr, 0, sizeof(void *) << (shift)); \
+}
+
+CTOR(0); CTOR(1); CTOR(2); CTOR(3); CTOR(4); CTOR(5); CTOR(6); CTOR(7);
+CTOR(8); CTOR(9); CTOR(10); CTOR(11); CTOR(12); CTOR(13); CTOR(14); CTOR(15);
+
+static inline void (*ctor(int shift))(void *)
+{
+ BUILD_BUG_ON(MAX_PGTABLE_INDEX_SIZE != 15);
+
+ switch (shift) {
+ case 0: return ctor_0;
+ case 1: return ctor_1;
+ case 2: return ctor_2;
+ case 3: return ctor_3;
+ case 4: return ctor_4;
+ case 5: return ctor_5;
+ case 6: return ctor_6;
+ case 7: return ctor_7;
+ case 8: return ctor_8;
+ case 9: return ctor_9;
+ case 10: return ctor_10;
+ case 11: return ctor_11;
+ case 12: return ctor_12;
+ case 13: return ctor_13;
+ case 14: return ctor_14;
+ case 15: return ctor_15;
+ }
+ return NULL;
+}
+
+struct kmem_cache *pgtable_cache[MAX_PGTABLE_INDEX_SIZE + 1];
+EXPORT_SYMBOL_GPL(pgtable_cache); /* used by kvm_hv module */
+
+/*
+ * Create a kmem_cache() for pagetables. This is not used for PTE
+ * pages - they're linked to struct page, come from the normal free
+ * pages pool and have a different entry size (see real_pte_t) to
+ * everything else. Caches created by this function are used for all
+ * the higher level pagetables, and for hugepage pagetables.
+ */
+void pgtable_cache_add(unsigned int shift)
+{
+ char *name;
+ unsigned long table_size = sizeof(void *) << shift;
+ unsigned long align = table_size;
+
+ /* When batching pgtable pointers for RCU freeing, we store
+ * the index size in the low bits. Table alignment must be
+ * big enough to fit it.
+ *
+ * Likewise, hugeapge pagetable pointers contain a (different)
+ * shift value in the low bits. All tables must be aligned so
+ * as to leave enough 0 bits in the address to contain it. */
+ unsigned long minalign = max(MAX_PGTABLE_INDEX_SIZE + 1,
+ HUGEPD_SHIFT_MASK + 1);
+ struct kmem_cache *new;
+
+ /* It would be nice if this was a BUILD_BUG_ON(), but at the
+ * moment, gcc doesn't seem to recognize is_power_of_2 as a
+ * constant expression, so so much for that. */
+ BUG_ON(!is_power_of_2(minalign));
+ BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
+
+ if (PGT_CACHE(shift))
+ return; /* Already have a cache of this size */
+
+ align = max_t(unsigned long, align, minalign);
+ name = kasprintf(GFP_KERNEL, "pgtable-2^%d", shift);
+ new = kmem_cache_create(name, table_size, align, 0, ctor(shift));
+ if (!new)
+ panic("Could not allocate pgtable cache for order %d", shift);
+
+ kfree(name);
+ pgtable_cache[shift] = new;
+
+ pr_debug("Allocated pgtable cache for order %d\n", shift);
+}
+EXPORT_SYMBOL_GPL(pgtable_cache_add); /* used by kvm_hv module */
+
+void pgtable_cache_init(void)
+{
+ pgtable_cache_add(PGD_INDEX_SIZE);
+
+ if (PMD_CACHE_INDEX)
+ pgtable_cache_add(PMD_CACHE_INDEX);
+ /*
+ * In all current configs, when the PUD index exists it's the
+ * same size as either the pgd or pmd index except with THP enabled
+ * on book3s 64
+ */
+ if (PUD_CACHE_INDEX)
+ pgtable_cache_add(PUD_CACHE_INDEX);
+}