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Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/include/asm/nohash/32/pgtable.h | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h new file mode 100644 index 000000000..0d40b3318 --- /dev/null +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h @@ -0,0 +1,371 @@ +/* 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 __ASSEMBLY__ +#include <linux/sched.h> +#include <linux/threads.h> +#include <asm/mmu.h> /* For sub-arch specific PPC_PIN_SIZE */ + +#ifdef CONFIG_44x +extern int icache_44x_need_flush; +#endif + +#endif /* __ASSEMBLY__ */ + +#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 __ASSEMBLY__ +#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 /* __ASSEMBLY__ */ + +#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 pte_ERROR(e) \ + pr_err("%s:%d: bad pte %llx.\n", __FILE__, __LINE__, \ + (unsigned long long)pte_val(e)) +#define pgd_ERROR(e) \ + pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e)) + +#ifndef __ASSEMBLY__ + +int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot); +void unmap_kernel_page(unsigned long va); + +#endif /* !__ASSEMBLY__ */ + + +/* + * 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 + */ +#include <asm/fixmap.h> + +/* + * 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_40x) +#include <asm/nohash/32/pte-40x.h> +#elif 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. + */ +#if defined(CONFIG_PPC32) && defined(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 + +/* + * _PAGE_CHG_MASK masks of bits that are to be preserved across + * pgprot changes. + */ +#define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_SPECIAL) + +#ifndef __ASSEMBLY__ + +#define pte_clear(mm, addr, ptep) \ + do { pte_update(mm, addr, ptep, ~0, 0, 0); } while (0) + +#ifndef pte_mkwrite +static inline pte_t pte_mkwrite(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_RW); +} +#endif + +static inline pte_t pte_mkdirty(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_DIRTY); +} + +static inline pte_t pte_mkyoung(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_ACCESSED); +} + +#ifndef pte_wrprotect +static inline pte_t pte_wrprotect(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_RW); +} +#endif + +#ifndef pte_mkexec +static inline pte_t pte_mkexec(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_EXEC); +} +#endif + +#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); +} + +/* + * PTE updates. This function is called whenever an existing + * valid PTE is updated. This does -not- include set_pte_at() + * which nowadays only sets a new PTE. + * + * Depending on the type of MMU, we may need to use atomic updates + * and the PTE may be either 32 or 64 bit wide. In the later case, + * when using atomic updates, only the low part of the PTE is + * accessed atomically. + * + * In addition, on 44x, we also maintain a global flag indicating + * that an executable user mapping was modified, which is needed + * to properly flush the virtually tagged instruction cache of + * those implementations. + * + * On the 8xx, the page tables are a bit special. For 16k pages, we have + * 4 identical entries. For 512k pages, we have 128 entries as if it was + * 4k pages, but they are flagged as 512k pages for the hardware. + * For other page sizes, we have a single entry in the table. + */ +#ifdef CONFIG_PPC_8xx +static pmd_t *pmd_off(struct mm_struct *mm, unsigned long addr); +static int hugepd_ok(hugepd_t hpd); + +static int number_of_cells_per_pte(pmd_t *pmd, pte_basic_t val, int huge) +{ + if (!huge) + return PAGE_SIZE / SZ_4K; + else if (hugepd_ok(*((hugepd_t *)pmd))) + return 1; + else if (IS_ENABLED(CONFIG_PPC_4K_PAGES) && !(val & _PAGE_HUGE)) + return SZ_16K / SZ_4K; + else + return SZ_512K / SZ_4K; +} + +static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p, + unsigned long clr, unsigned long set, int huge) +{ + pte_basic_t *entry = (pte_basic_t *)p; + pte_basic_t old = pte_val(*p); + pte_basic_t new = (old & ~(pte_basic_t)clr) | set; + int num, i; + pmd_t *pmd = pmd_off(mm, addr); + + num = number_of_cells_per_pte(pmd, new, huge); + + for (i = 0; i < num; i++, entry++, new += SZ_4K) + *entry = new; + + return old; +} + +#ifdef CONFIG_PPC_16K_PAGES +#define __HAVE_ARCH_PTEP_GET +static inline pte_t ptep_get(pte_t *ptep) +{ + pte_basic_t val = READ_ONCE(ptep->pte); + pte_t pte = {val, val, val, val}; + + return pte; +} +#endif /* CONFIG_PPC_16K_PAGES */ + +#else +static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p, + unsigned long clr, unsigned long set, int huge) +{ + pte_basic_t old = pte_val(*p); + pte_basic_t new = (old & ~(pte_basic_t)clr) | set; + + *p = __pte(new); + +#ifdef CONFIG_44x + if ((old & _PAGE_USER) && (old & _PAGE_EXEC)) + icache_44x_need_flush = 1; +#endif + return old; +} +#endif + +#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG +static inline int __ptep_test_and_clear_young(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + unsigned long old; + old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0); + return (old & _PAGE_ACCESSED) != 0; +} +#define ptep_test_and_clear_young(__vma, __addr, __ptep) \ + __ptep_test_and_clear_young((__vma)->vm_mm, __addr, __ptep) + +#define __HAVE_ARCH_PTEP_GET_AND_CLEAR +static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, + pte_t *ptep) +{ + return __pte(pte_update(mm, addr, ptep, ~0, 0, 0)); +} + +#define __HAVE_ARCH_PTEP_SET_WRPROTECT +#ifndef ptep_set_wrprotect +static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, + pte_t *ptep) +{ + pte_update(mm, addr, ptep, _PAGE_RW, 0, 0); +} +#endif + +#ifndef __ptep_set_access_flags +static inline void __ptep_set_access_flags(struct vm_area_struct *vma, + pte_t *ptep, pte_t entry, + unsigned long address, + int psize) +{ + unsigned long set = pte_val(entry) & + (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC); + int huge = psize > mmu_virtual_psize ? 1 : 0; + + pte_update(vma->vm_mm, address, ptep, 0, set, huge); + + flush_tlb_page(vma, address); +} +#endif + +static inline int pte_young(pte_t pte) +{ + return pte_val(pte) & _PAGE_ACCESSED; +} + +/* + * 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) \ + ((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 and decode a swap entry. + * Note that the bits we use in a PTE for representing a swap entry + * must not include the _PAGE_PRESENT bit. + * -- paulus + */ +#define __swp_type(entry) ((entry).val & 0x1f) +#define __swp_offset(entry) ((entry).val >> 5) +#define __swp_entry(type, offset) ((swp_entry_t) { (type) | ((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 }) + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_POWERPC_NOHASH_32_PGTABLE_H */ |