diff options
Diffstat (limited to 'arch/powerpc/include/asm/book3s/32/pgtable.h')
-rw-r--r-- | arch/powerpc/include/asm/book3s/32/pgtable.h | 406 |
1 files changed, 194 insertions, 212 deletions
diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h index 0796533d37dd..52971ee30717 100644 --- a/arch/powerpc/include/asm/book3s/32/pgtable.h +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -2,27 +2,52 @@ #ifndef _ASM_POWERPC_BOOK3S_32_PGTABLE_H #define _ASM_POWERPC_BOOK3S_32_PGTABLE_H -#define __ARCH_USE_5LEVEL_HACK #include <asm-generic/pgtable-nopmd.h> -#include <asm/book3s/32/hash.h> +/* + * The "classic" 32-bit implementation of the PowerPC MMU uses a hash + * table containing PTEs, together with a set of 16 segment registers, + * to define the virtual to physical address mapping. + * + * We use the hash table as an extended TLB, i.e. a cache of currently + * active mappings. We maintain a two-level page table tree, much + * like that used by the i386, for the sake of the Linux memory + * management code. Low-level assembler code in hash_low_32.S + * (procedure hash_page) is responsible for extracting ptes from the + * tree and putting them into the hash table when necessary, and + * updating the accessed and modified bits in the page table tree. + */ -/* And here we include common definitions */ +#define _PAGE_PRESENT 0x001 /* software: pte contains a translation */ +#define _PAGE_HASHPTE 0x002 /* hash_page has made an HPTE for this pte */ +#define _PAGE_READ 0x004 /* software: read access allowed */ +#define _PAGE_GUARDED 0x008 /* G: prohibit speculative access */ +#define _PAGE_COHERENT 0x010 /* M: enforce memory coherence (SMP systems) */ +#define _PAGE_NO_CACHE 0x020 /* I: cache inhibit */ +#define _PAGE_WRITETHRU 0x040 /* W: cache write-through */ +#define _PAGE_DIRTY 0x080 /* C: page changed */ +#define _PAGE_ACCESSED 0x100 /* R: page referenced */ +#define _PAGE_EXEC 0x200 /* software: exec allowed */ +#define _PAGE_WRITE 0x400 /* software: user write access allowed */ +#define _PAGE_SPECIAL 0x800 /* software: Special page */ -#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) +#ifdef CONFIG_PTE_64BIT +/* We never clear the high word of the pte */ +#define _PTE_NONE_MASK (0xffffffff00000000ULL | _PAGE_HASHPTE) +#else +#define _PTE_NONE_MASK _PAGE_HASHPTE +#endif -#define _PAGE_HPTEFLAGS _PAGE_HASHPTE +#define _PMD_PRESENT 0 +#define _PMD_PRESENT_MASK (PAGE_MASK) +#define _PMD_BAD (~PAGE_MASK) -#ifndef __ASSEMBLY__ +/* We borrow the _PAGE_READ bit to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE _PAGE_READ -static inline bool pte_user(pte_t pte) -{ - return pte_val(pte) & _PAGE_USER; -} -#endif /* __ASSEMBLY__ */ +/* And here we include common definitions */ + +#define _PAGE_HPTEFLAGS _PAGE_HASHPTE /* * Location of the PFN in the PTE. Most 32-bit platforms use the same @@ -37,8 +62,10 @@ static inline bool pte_user(pte_t pte) */ #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 /* @@ -57,49 +84,16 @@ static inline bool pte_user(pte_t pte) #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) +#include <asm/pgtable-masks.h> /* 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_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 @@ -113,6 +107,9 @@ static inline bool pte_user(pte_t pte) #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) @@ -138,6 +135,7 @@ static inline bool pte_user(pte_t pte) #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__ */ @@ -146,7 +144,14 @@ int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot); * value (for now) on others, from where we can start layout kernel * virtual space that goes below PKMAP and FIXMAP */ -#include <asm/fixmap.h> + +#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, @@ -182,18 +187,16 @@ int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot); */ #define VMALLOC_OFFSET (0x1000000) /* 16M */ -/* - * With CONFIG_STRICT_KERNEL_RWX, kernel segments are set NX. But when modules - * are used, NX cannot be set on VMALLOC space. So vmalloc VM space and linear - * memory shall not share segments. - */ -#if defined(CONFIG_STRICT_KERNEL_RWX) && defined(CONFIG_MODULES) -#define VMALLOC_START ((_ALIGN((long)high_memory, 256L << 20) + 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 + +#define MODULES_END ALIGN_DOWN(PAGE_OFFSET, SZ_256M) +#define MODULES_VADDR (MODULES_END - SZ_256M) #ifndef __ASSEMBLY__ #include <linux/sched.h> @@ -202,9 +205,6 @@ int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot); /* 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)) /* @@ -213,7 +213,7 @@ int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot); */ #define pte_clear(mm, addr, ptep) \ - do { pte_update(ptep, ~_PAGE_HASHPTE, 0); } while (0) + 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) @@ -236,8 +236,14 @@ 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); +static inline void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr) +{ + if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) { + unsigned long ptephys = __pa(ptep) & PAGE_MASK; + + flush_hash_pages(mm->context.id, addr, ptephys, 1); + } +} /* * PTE updates. This function is called whenever an existing @@ -248,84 +254,74 @@ extern void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, * 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. */ +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; + + if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) { + 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 -static inline unsigned long pte_update(pte_t *p, - unsigned long clr, - unsigned long set) -{ - unsigned long old, tmp; - - __asm__ __volatile__("\ -1: lwarx %0,0,%3\n\ - andc %1,%0,%4\n\ - or %1,%1,%5\n" -" stwcx. %1,0,%3\n\ - bne- 1b" - : "=&r" (old), "=&r" (tmp), "=m" (*p) - : "r" (p), "r" (clr), "r" (set), "m" (*p) - : "cc" ); + : "r" (p), +#else + : "b" ((unsigned long)(p) + 4), +#endif + "r" (clr), "r" (set), "m" (*p) + : "cc" ); + } else { + old = pte_val(*p); - return old; -} -#else /* CONFIG_PTE_64BIT */ -static inline unsigned long long pte_update(pte_t *p, - unsigned long clr, - unsigned long set) -{ - unsigned long long old; - unsigned long tmp; - - __asm__ __volatile__("\ -1: lwarx %L0,0,%4\n\ - lwzx %0,0,%3\n\ - andc %1,%L0,%5\n\ - or %1,%1,%6\n" -" stwcx. %1,0,%4\n\ - bne- 1b" - : "=&r" (old), "=&r" (tmp), "=m" (*p) - : "r" (p), "r" ((unsigned long)(p) + 4), "r" (clr), "r" (set), "m" (*p) - : "cc" ); + *p = __pte((old & ~(pte_basic_t)clr) | set); + } return old; } -#endif /* CONFIG_PTE_64BIT */ /* * 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(unsigned int context, unsigned long addr, pte_t *ptep) +static inline int __ptep_test_and_clear_young(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) { unsigned long old; - old = pte_update(ptep, _PAGE_ACCESSED, 0); - if (old & _PAGE_HASHPTE) { - unsigned long ptephys = __pa(ptep) & PAGE_MASK; - flush_hash_pages(context, addr, ptephys, 1); - } + old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0); + if (old & _PAGE_HASHPTE) + flush_hash_entry(mm, ptep, addr); + return (old & _PAGE_ACCESSED) != 0; } #define ptep_test_and_clear_young(__vma, __addr, __ptep) \ - __ptep_test_and_clear_young((__vma)->vm_mm->context.id, __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(ptep, ~_PAGE_HASHPTE, 0)); + 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(ptep, _PAGE_RW, 0); + pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 0); } static inline void __ptep_set_access_flags(struct vm_area_struct *vma, @@ -336,7 +332,7 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma, unsigned long set = pte_val(entry) & (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC); - pte_update(ptep, 0, set); + pte_update(vma->vm_mm, address, ptep, 0, set, 0); flush_tlb_page(vma, address); } @@ -344,43 +340,56 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma, #define __HAVE_ARCH_PTE_SAME #define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0) -#define pmd_page_vaddr(pmd) \ - ((unsigned long)__va(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1))) -#define pmd_page(pmd) \ - pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT) - -/* to find an entry in a kernel page-table-directory */ -#define pgd_offset_k(address) pgd_offset(&init_mm, address) - -/* to find an entry in a page-table-directory */ -#define pgd_index(address) ((address) >> PGDIR_SHIFT) -#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address)) - -/* Find an entry in the third-level page table.. */ -#define pte_index(address) \ - (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) -#define pte_offset_kernel(dir, addr) \ - ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr)) -#define pte_offset_map(dir, addr) \ - ((pte_t *)(kmap_atomic(pmd_page(*(dir))) + \ - (pmd_page_vaddr(*(dir)) & ~PAGE_MASK)) + pte_index(addr)) -#define pte_unmap(pte) kunmap_atomic(pte) +#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT) +#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 or the _PAGE_HASHPTE bit (if used). - * -- paulus + * 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 H P + * + * E is the exclusive marker that is not stored in swap entries. + * _PAGE_PRESENT (P) and __PAGE_HASHPTE (H) must be 0. + * + * 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) | ((offset) << 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 }) +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte_val(pte) & _PAGE_SWP_EXCLUSIVE; +} + +static inline pte_t pte_swp_mkexclusive(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_SWP_EXCLUSIVE); +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE); +} + /* 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 bool pte_read(pte_t pte) +{ + return !!(pte_val(pte) & _PAGE_READ); +} + +static inline bool pte_write(pte_t pte) +{ + return !!(pte_val(pte) & _PAGE_WRITE); +} + 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); } @@ -415,10 +424,10 @@ static inline bool pte_ci(pte_t pte) 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 + * A read-only access is controlled by _PAGE_READ bit. + * We have _PAGE_READ set for WRITE */ - if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte)) + if (!pte_present(pte) || !pte_read(pte)) return false; if (write && !pte_write(pte)) @@ -439,15 +448,10 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot) 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); + return __pte(pte_val(pte) & ~_PAGE_WRITE); } static inline pte_t pte_exprotect(pte_t pte) @@ -475,8 +479,11 @@ static inline pte_t pte_mkpte(pte_t pte) return pte; } -static inline pte_t pte_mkwrite(pte_t pte) +static inline pte_t pte_mkwrite_novma(pte_t pte) { + /* + * write implies read, hence set both + */ return __pte(pte_val(pte) | _PAGE_RW); } @@ -500,16 +507,6 @@ 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)); @@ -518,58 +515,43 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t 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 + * Setting the PTE depends on the MMU type and other factors. + * + * First case is 32-bit in UP mode with 32-bit PTEs, 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. + * + * 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 fallback to the simple update preserving + * the hash bits (ie, same as the non-SMP case). + * + * Third case is 32-bit 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 also do a simple update preserving + * the hash bits instead. */ 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(ptep, ~_PAGE_HASHPTE, pte_val(pte)); - -#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 ((!IS_ENABLED(CONFIG_SMP) && !IS_ENABLED(CONFIG_PTE_64BIT)) || percpu) { + *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE) | + (pte_val(pte) & ~_PAGE_HASHPTE)); + } else if (IS_ENABLED(CONFIG_PTE_64BIT)) { + if (pte_val(*ptep) & _PAGE_HASHPTE) + flush_hash_entry(mm, ptep, addr); + + asm volatile("stw%X0 %2,%0; eieio; stw%X1 %L2,%1" : + "=m" (*ptep), "=m" (*((unsigned char *)ptep+4)) : + "r" (pte) : "memory"); + } else { + pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, pte_val(pte), 0); } - if (pte_val(*ptep) & _PAGE_HASHPTE) - flush_hash_entry(mm, ptep, addr); - __asm__ __volatile__("\ - stw%U0%X0 %2,%0\n\ - eieio\n\ - stw%U0%X0 %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 } /* |