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-rw-r--r--arch/powerpc/include/asm/nohash/32/pgtable.h204
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diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
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index 000000000000..2d71e4b7cd09
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+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -0,0 +1,204 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_NOHASH_32_PGTABLE_H
+#define _ASM_POWERPC_NOHASH_32_PGTABLE_H
+
+#include <asm-generic/pgtable-nopmd.h>
+
+#ifndef __ASSEMBLER__
+#include <linux/sched.h>
+#include <linux/threads.h>
+#include <asm/mmu.h> /* For sub-arch specific PPC_PIN_SIZE */
+
+#endif /* __ASSEMBLER__ */
+
+#define PTE_INDEX_SIZE PTE_SHIFT
+#define PMD_INDEX_SIZE 0
+#define PUD_INDEX_SIZE 0
+#define PGD_INDEX_SIZE (32 - PGDIR_SHIFT)
+
+#define PMD_CACHE_INDEX PMD_INDEX_SIZE
+#define PUD_CACHE_INDEX PUD_INDEX_SIZE
+
+#ifndef __ASSEMBLER__
+#define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_INDEX_SIZE)
+#define PMD_TABLE_SIZE 0
+#define PUD_TABLE_SIZE 0
+#define PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
+
+#define PMD_MASKED_BITS (PTE_TABLE_SIZE - 1)
+#endif /* __ASSEMBLER__ */
+
+#define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
+#define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)
+
+/*
+ * The normal case is that PTEs are 32-bits and we have a 1-page
+ * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages. -- paulus
+ *
+ * For any >32-bit physical address platform, we can use the following
+ * two level page table layout where the pgdir is 8KB and the MS 13 bits
+ * are an index to the second level table. The combined pgdir/pmd first
+ * level has 2048 entries and the second level has 512 64-bit PTE entries.
+ * -Matt
+ */
+/* PGDIR_SHIFT determines what a top-level page table entry can map */
+#define PGDIR_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
+#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+
+/* Bits to mask out from a PGD to get to the PUD page */
+#define PGD_MASKED_BITS 0
+
+#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
+
+#define pgd_ERROR(e) \
+ pr_err("%s:%d: bad pgd %08llx.\n", __FILE__, __LINE__, (unsigned long long)pgd_val(e))
+
+/*
+ * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
+ * value (for now) on others, from where we can start layout kernel
+ * virtual space that goes below PKMAP and FIXMAP
+ */
+
+#define FIXADDR_SIZE 0
+#ifdef CONFIG_KASAN
+#include <asm/kasan.h>
+#define FIXADDR_TOP (KASAN_SHADOW_START - PAGE_SIZE)
+#else
+#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
+#endif
+
+/*
+ * ioremap_bot starts at that address. Early ioremaps move down from there,
+ * until mem_init() at which point this becomes the top of the vmalloc
+ * and ioremap space
+ */
+#ifdef CONFIG_HIGHMEM
+#define IOREMAP_TOP PKMAP_BASE
+#else
+#define IOREMAP_TOP FIXADDR_START
+#endif
+
+/* PPC32 shares vmalloc area with ioremap */
+#define IOREMAP_START VMALLOC_START
+#define IOREMAP_END VMALLOC_END
+
+/*
+ * Just any arbitrary offset to the start of the vmalloc VM area: the
+ * current 16MB value just means that there will be a 64MB "hole" after the
+ * physical memory until the kernel virtual memory starts. That means that
+ * any out-of-bounds memory accesses will hopefully be caught.
+ * The vmalloc() routines leaves a hole of 4kB between each vmalloced
+ * area for the same reason. ;)
+ *
+ * We no longer map larger than phys RAM with the BATs so we don't have
+ * to worry about the VMALLOC_OFFSET causing problems. We do have to worry
+ * about clashes between our early calls to ioremap() that start growing down
+ * from IOREMAP_TOP being run into the VM area allocations (growing upwards
+ * from VMALLOC_START). For this reason we have ioremap_bot to check when
+ * we actually run into our mappings setup in the early boot with the VM
+ * system. This really does become a problem for machines with good amounts
+ * of RAM. -- Cort
+ */
+#define VMALLOC_OFFSET (0x1000000) /* 16M */
+#ifdef PPC_PIN_SIZE
+#define VMALLOC_START (((ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#else
+#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#endif
+
+#ifdef CONFIG_KASAN_VMALLOC
+#define VMALLOC_END ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
+#else
+#define VMALLOC_END ioremap_bot
+#endif
+
+/*
+ * Bits in a linux-style PTE. These match the bits in the
+ * (hardware-defined) PowerPC PTE as closely as possible.
+ */
+
+#if defined(CONFIG_44x)
+#include <asm/nohash/32/pte-44x.h>
+#elif defined(CONFIG_PPC_85xx) && defined(CONFIG_PTE_64BIT)
+#include <asm/nohash/pte-e500.h>
+#elif defined(CONFIG_PPC_85xx)
+#include <asm/nohash/32/pte-85xx.h>
+#elif defined(CONFIG_PPC_8xx)
+#include <asm/nohash/32/pte-8xx.h>
+#endif
+
+/*
+ * Location of the PFN in the PTE. Most 32-bit platforms use the same
+ * as _PAGE_SHIFT here (ie, naturally aligned).
+ * Platform who don't just pre-define the value so we don't override it here.
+ */
+#ifndef PTE_RPN_SHIFT
+#define PTE_RPN_SHIFT (PAGE_SHIFT)
+#endif
+
+/*
+ * The mask covered by the RPN must be a ULL on 32-bit platforms with
+ * 64-bit PTEs.
+ */
+#ifdef CONFIG_PTE_64BIT
+#define PTE_RPN_MASK (~((1ULL << PTE_RPN_SHIFT) - 1))
+#define MAX_POSSIBLE_PHYSMEM_BITS 36
+#else
+#define PTE_RPN_MASK (~((1UL << PTE_RPN_SHIFT) - 1))
+#define MAX_POSSIBLE_PHYSMEM_BITS 32
+#endif
+
+#ifndef __ASSEMBLER__
+
+#define pmd_none(pmd) (!pmd_val(pmd))
+#define pmd_bad(pmd) (pmd_val(pmd) & _PMD_BAD)
+#define pmd_present(pmd) (pmd_val(pmd) & _PMD_PRESENT_MASK)
+static inline void pmd_clear(pmd_t *pmdp)
+{
+ *pmdp = __pmd(0);
+}
+
+/*
+ * Note that on Book E processors, the pmd contains the kernel virtual
+ * (lowmem) address of the pte page. The physical address is less useful
+ * because everything runs with translation enabled (even the TLB miss
+ * handler). On everything else the pmd contains the physical address
+ * of the pte page. -- paulus
+ */
+#ifndef CONFIG_BOOKE
+#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
+#else
+#define pmd_page_vaddr(pmd) \
+ ((const void *)((unsigned long)pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
+#define pmd_pfn(pmd) (__pa(pmd_val(pmd)) >> PAGE_SHIFT)
+#endif
+
+#define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
+
+/*
+ * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
+ * are !pte_none() && !pte_present().
+ *
+ * Format of swap PTEs (32bit PTEs):
+ *
+ * 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * <------------------ offset -------------------> < type -> E 0 0
+ *
+ * E is the exclusive marker that is not stored in swap entries.
+ *
+ * For 64bit PTEs, the offset is extended by 32bit.
+ */
+#define __swp_type(entry) ((entry).val & 0x1f)
+#define __swp_offset(entry) ((entry).val >> 5)
+#define __swp_entry(type, offset) ((swp_entry_t) { ((type) & 0x1f) | ((offset) << 5) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 3 })
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 3 })
+
+/* We borrow LSB 2 to store the exclusive marker in swap PTEs. */
+#define _PAGE_SWP_EXCLUSIVE 0x000004
+
+#endif /* !__ASSEMBLER__ */
+
+#endif /* __ASM_POWERPC_NOHASH_32_PGTABLE_H */