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Diffstat (limited to 'arch/powerpc/include/asm/book3s/32/pgtable.h')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/32/pgtable.h | 594 |
1 files changed, 594 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h new file mode 100644 index 000000000..94c5c6623 --- /dev/null +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -0,0 +1,594 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_BOOK3S_32_PGTABLE_H +#define _ASM_POWERPC_BOOK3S_32_PGTABLE_H + +#include <asm-generic/pgtable-nopmd.h> + +#include <asm/book3s/32/hash.h> + +/* And here we include common definitions */ + +#define _PAGE_KERNEL_RO 0 +#define _PAGE_KERNEL_ROX (_PAGE_EXEC) +#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW) +#define _PAGE_KERNEL_RWX (_PAGE_DIRTY | _PAGE_RW | _PAGE_EXEC) + +#define _PAGE_HPTEFLAGS _PAGE_HASHPTE + +#ifndef __ASSEMBLY__ + +static inline bool pte_user(pte_t pte) +{ + return pte_val(pte) & _PAGE_USER; +} +#endif /* __ASSEMBLY__ */ + +/* + * 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. + */ +#define PTE_RPN_SHIFT (PAGE_SHIFT) + +/* + * 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 + +/* + * _PAGE_CHG_MASK masks of bits that are to be preserved across + * pgprot changes. + */ +#define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HASHPTE | _PAGE_DIRTY | \ + _PAGE_ACCESSED | _PAGE_SPECIAL) + +/* + * We define 2 sets of base prot bits, one for basic pages (ie, + * cacheable kernel and user pages) and one for non cacheable + * pages. We always set _PAGE_COHERENT when SMP is enabled or + * the processor might need it for DMA coherency. + */ +#define _PAGE_BASE_NC (_PAGE_PRESENT | _PAGE_ACCESSED) +#define _PAGE_BASE (_PAGE_BASE_NC | _PAGE_COHERENT) + +/* + * Permission masks used to generate the __P and __S table. + * + * Note:__pgprot is defined in arch/powerpc/include/asm/page.h + * + * Write permissions imply read permissions for now. + */ +#define PAGE_NONE __pgprot(_PAGE_BASE) +#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW) +#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC) +#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER) +#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) +#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER) +#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) + +/* Permission masks used for kernel mappings */ +#define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW) +#define PAGE_KERNEL_NC __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | _PAGE_NO_CACHE) +#define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \ + _PAGE_NO_CACHE | _PAGE_GUARDED) +#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RWX) +#define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO) +#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX) + +/* + * Protection used for kernel text. We want the debuggers to be able to + * set breakpoints anywhere, so don't write protect the kernel text + * on platforms where such control is possible. + */ +#if defined(CONFIG_KGDB) || defined(CONFIG_XMON) || defined(CONFIG_BDI_SWITCH) ||\ + defined(CONFIG_KPROBES) || defined(CONFIG_DYNAMIC_FTRACE) +#define PAGE_KERNEL_TEXT PAGE_KERNEL_X +#else +#define PAGE_KERNEL_TEXT PAGE_KERNEL_ROX +#endif + +/* Make modules code happy. We don't set RO yet */ +#define PAGE_KERNEL_EXEC PAGE_KERNEL_X + +/* Advertise special mapping type for AGP */ +#define PAGE_AGP (PAGE_KERNEL_NC) +#define HAVE_PAGE_AGP + +#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) + +/* Bits to mask out from a PMD to get to the PTE page */ +#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)) + +#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) + +#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_base 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 */ + +#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))) + +#ifdef CONFIG_KASAN_VMALLOC +#define VMALLOC_END ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT) +#else +#define VMALLOC_END ioremap_bot +#endif + +#ifdef CONFIG_STRICT_KERNEL_RWX +#define MODULES_END ALIGN_DOWN(PAGE_OFFSET, SZ_256M) +#define MODULES_VADDR (MODULES_END - SZ_256M) +#endif + +#ifndef __ASSEMBLY__ +#include <linux/sched.h> +#include <linux/threads.h> + +/* Bits to mask out from a PGD to get to the PUD page */ +#define PGD_MASKED_BITS 0 + +#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)) +/* + * Bits in a linux-style PTE. These match the bits in the + * (hardware-defined) PowerPC PTE as closely as possible. + */ + +#define pte_clear(mm, addr, ptep) \ + do { pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0); } while (0) + +#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); +} + + +/* + * When flushing the tlb entry for a page, we also need to flush the hash + * table entry. flush_hash_pages is assembler (for speed) in hashtable.S. + */ +extern int flush_hash_pages(unsigned context, unsigned long va, + unsigned long pmdval, int count); + +/* Add an HPTE to the hash table */ +extern void add_hash_page(unsigned context, unsigned long va, + unsigned long pmdval); + +/* Flush an entry from the TLB/hash table */ +extern void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, + unsigned long address); + +/* + * 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. + */ +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; + unsigned long tmp; + + __asm__ __volatile__( +#ifndef CONFIG_PTE_64BIT +"1: lwarx %0, 0, %3\n" +" andc %1, %0, %4\n" +#else +"1: lwarx %L0, 0, %3\n" +" lwz %0, -4(%3)\n" +" andc %1, %L0, %4\n" +#endif +" or %1, %1, %5\n" +" stwcx. %1, 0, %3\n" +" bne- 1b" + : "=&r" (old), "=&r" (tmp), "=m" (*p) +#ifndef CONFIG_PTE_64BIT + : "r" (p), +#else + : "b" ((unsigned long)(p) + 4), +#endif + "r" (clr), "r" (set), "m" (*p) + : "cc" ); + + return old; +} + +/* + * 2.6 calls this without flushing the TLB entry; this is wrong + * for our hash-based implementation, we fix that up here. + */ +#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); + if (old & _PAGE_HASHPTE) { + unsigned long ptephys = __pa(ptep) & PAGE_MASK; + flush_hash_pages(mm->context.id, addr, ptephys, 1); + } + 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, ~_PAGE_HASHPTE, 0, 0)); +} + +#define __HAVE_ARCH_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); +} + +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); + + pte_update(vma->vm_mm, address, ptep, 0, set, 0); + + flush_tlb_page(vma, address); +} + +#define __HAVE_ARCH_PTE_SAME +#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0) + +#define pmd_page(pmd) \ + pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT) + +/* + * 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 or the _PAGE_HASHPTE bit (if used). + * -- 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 }) + +/* Generic accessors to PTE bits */ +static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);} +static inline int pte_read(pte_t pte) { return 1; } +static inline int pte_dirty(pte_t pte) { return !!(pte_val(pte) & _PAGE_DIRTY); } +static inline int pte_young(pte_t pte) { return !!(pte_val(pte) & _PAGE_ACCESSED); } +static inline int pte_special(pte_t pte) { return !!(pte_val(pte) & _PAGE_SPECIAL); } +static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; } +static inline bool pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; } + +static inline int pte_present(pte_t pte) +{ + return pte_val(pte) & _PAGE_PRESENT; +} + +static inline bool pte_hw_valid(pte_t pte) +{ + return pte_val(pte) & _PAGE_PRESENT; +} + +static inline bool pte_hashpte(pte_t pte) +{ + return !!(pte_val(pte) & _PAGE_HASHPTE); +} + +static inline bool pte_ci(pte_t pte) +{ + return !!(pte_val(pte) & _PAGE_NO_CACHE); +} + +/* + * We only find page table entry in the last level + * Hence no need for other accessors + */ +#define pte_access_permitted pte_access_permitted +static inline bool pte_access_permitted(pte_t pte, bool write) +{ + /* + * A read-only access is controlled by _PAGE_USER bit. + * We have _PAGE_READ set for WRITE and EXECUTE + */ + if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte)) + return false; + + if (write && !pte_write(pte)) + return false; + + return true; +} + +/* Conversion functions: convert a page and protection to a page entry, + * and a page entry and page directory to the page they refer to. + * + * Even if PTEs can be unsigned long long, a PFN is always an unsigned + * long for now. + */ +static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot) +{ + return __pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) | + pgprot_val(pgprot)); +} + +static inline unsigned long pte_pfn(pte_t pte) +{ + return pte_val(pte) >> PTE_RPN_SHIFT; +} + +/* Generic modifiers for PTE bits */ +static inline pte_t pte_wrprotect(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_RW); +} + +static inline pte_t pte_exprotect(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_EXEC); +} + +static inline pte_t pte_mkclean(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_DIRTY); +} + +static inline pte_t pte_mkold(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_ACCESSED); +} + +static inline pte_t pte_mkexec(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_EXEC); +} + +static inline pte_t pte_mkpte(pte_t pte) +{ + return pte; +} + +static inline pte_t pte_mkwrite(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_RW); +} + +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); +} + +static inline pte_t pte_mkspecial(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_SPECIAL); +} + +static inline pte_t pte_mkhuge(pte_t pte) +{ + return pte; +} + +static inline pte_t pte_mkprivileged(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_USER); +} + +static inline pte_t pte_mkuser(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_USER); +} + +static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) +{ + return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot)); +} + + + +/* This low level function performs the actual PTE insertion + * Setting the PTE depends on the MMU type and other factors. It's + * an horrible mess that I'm not going to try to clean up now but + * I'm keeping it in one place rather than spread around + */ +static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte, int percpu) +{ +#if defined(CONFIG_SMP) && !defined(CONFIG_PTE_64BIT) + /* First case is 32-bit Hash MMU in SMP mode with 32-bit PTEs. We use the + * helper pte_update() which does an atomic update. We need to do that + * because a concurrent invalidation can clear _PAGE_HASHPTE. If it's a + * per-CPU PTE such as a kmap_atomic, we do a simple update preserving + * the hash bits instead (ie, same as the non-SMP case) + */ + if (percpu) + *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE) + | (pte_val(pte) & ~_PAGE_HASHPTE)); + else + pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, pte_val(pte), 0); + +#elif defined(CONFIG_PTE_64BIT) + /* Second case is 32-bit with 64-bit PTE. In this case, we + * can just store as long as we do the two halves in the right order + * with a barrier in between. This is possible because we take care, + * in the hash code, to pre-invalidate if the PTE was already hashed, + * which synchronizes us with any concurrent invalidation. + * In the percpu case, we also fallback to the simple update preserving + * the hash bits + */ + if (percpu) { + *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE) + | (pte_val(pte) & ~_PAGE_HASHPTE)); + return; + } + if (pte_val(*ptep) & _PAGE_HASHPTE) + flush_hash_entry(mm, ptep, addr); + __asm__ __volatile__("\ + stw%X0 %2,%0\n\ + eieio\n\ + stw%X1 %L2,%1" + : "=m" (*ptep), "=m" (*((unsigned char *)ptep+4)) + : "r" (pte) : "memory"); + +#else + /* Third case is 32-bit hash table in UP mode, we need to preserve + * the _PAGE_HASHPTE bit since we may not have invalidated the previous + * translation in the hash yet (done in a subsequent flush_tlb_xxx()) + * and see we need to keep track that this PTE needs invalidating + */ + *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE) + | (pte_val(pte) & ~_PAGE_HASHPTE)); +#endif +} + +/* + * Macro to mark a page protection value as "uncacheable". + */ + +#define _PAGE_CACHE_CTL (_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \ + _PAGE_WRITETHRU) + +#define pgprot_noncached pgprot_noncached +static inline pgprot_t pgprot_noncached(pgprot_t prot) +{ + return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | + _PAGE_NO_CACHE | _PAGE_GUARDED); +} + +#define pgprot_noncached_wc pgprot_noncached_wc +static inline pgprot_t pgprot_noncached_wc(pgprot_t prot) +{ + return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | + _PAGE_NO_CACHE); +} + +#define pgprot_cached pgprot_cached +static inline pgprot_t pgprot_cached(pgprot_t prot) +{ + return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | + _PAGE_COHERENT); +} + +#define pgprot_cached_wthru pgprot_cached_wthru +static inline pgprot_t pgprot_cached_wthru(pgprot_t prot) +{ + return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | + _PAGE_COHERENT | _PAGE_WRITETHRU); +} + +#define pgprot_cached_noncoherent pgprot_cached_noncoherent +static inline pgprot_t pgprot_cached_noncoherent(pgprot_t prot) +{ + return __pgprot(pgprot_val(prot) & ~_PAGE_CACHE_CTL); +} + +#define pgprot_writecombine pgprot_writecombine +static inline pgprot_t pgprot_writecombine(pgprot_t prot) +{ + return pgprot_noncached_wc(prot); +} + +#endif /* !__ASSEMBLY__ */ + +#endif /* _ASM_POWERPC_BOOK3S_32_PGTABLE_H */ |