From c7d54842deb1fa357cff75b988275a1c9f259140 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Fri, 29 Apr 2016 23:25:30 +1000 Subject: [PATCH] powerpc/mm: Use _PAGE_READ to indicate Read access This splits the _PAGE_RW bit into _PAGE_READ and _PAGE_WRITE. It also removes the dependency on _PAGE_USER for implying read only. Few things to note here is that, we have read implied with write and execute permission. Hence we should always find _PAGE_READ set on hash pte fault. We still can't switch PROT_NONE to !(_PAGE_RWX). Auto numa depends on marking a prot none pte _PAGE_WRITE. (For more details look at b191f9b106ea "mm: numa: preserve PTE write permissions across a NUMA hinting fault") Cc: Arnd Bergmann Cc: Jeremy Kerr Cc: Frederic Barrat Acked-by: Ian Munsie Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/book3s/64/hash-64k.h | 4 +-- arch/powerpc/include/asm/book3s/64/hash.h | 35 +++++++++++-------- arch/powerpc/include/asm/pte-common.h | 5 +++ arch/powerpc/mm/hash64_4k.c | 2 +- arch/powerpc/mm/hash64_64k.c | 4 +-- arch/powerpc/mm/hash_utils_64.c | 9 ++--- arch/powerpc/mm/hugepage-hash64.c | 2 +- arch/powerpc/mm/hugetlbpage-hash64.c | 2 +- arch/powerpc/mm/hugetlbpage.c | 4 +-- arch/powerpc/mm/pgtable.c | 4 +-- arch/powerpc/mm/pgtable_64.c | 5 ++- arch/powerpc/platforms/cell/spu_base.c | 2 +- arch/powerpc/platforms/cell/spufs/fault.c | 4 +-- drivers/misc/cxl/fault.c | 4 +-- 14 files changed, 49 insertions(+), 37 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h index f4949f117057..f4650504a61e 100644 --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h @@ -291,10 +291,10 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp) { - if ((pmd_val(*pmdp) & _PAGE_RW) == 0) + if ((pmd_val(*pmdp) & _PAGE_WRITE) == 0) return; - pmd_hugepage_update(mm, addr, pmdp, _PAGE_RW, 0); + pmd_hugepage_update(mm, addr, pmdp, _PAGE_WRITE, 0); } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h index 22064bd329f2..fb76f9cf49c9 100644 --- a/arch/powerpc/include/asm/book3s/64/hash.h +++ b/arch/powerpc/include/asm/book3s/64/hash.h @@ -16,8 +16,10 @@ #define _PAGE_BIT_SWAP_TYPE 0 #define _PAGE_EXEC 0x00001 /* execute permission */ -#define _PAGE_RW 0x00002 /* read & write access allowed */ +#define _PAGE_WRITE 0x00002 /* write access allowed */ #define _PAGE_READ 0x00004 /* read access allowed */ +#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE) +#define _PAGE_RWX (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC) #define _PAGE_USER 0x00008 /* page may be accessed by userspace */ #define _PAGE_GUARDED 0x00010 /* G: guarded (side-effect) page */ /* M (memory coherence) is always set in the HPTE, so we don't need it here */ @@ -145,8 +147,8 @@ */ #define PAGE_PROT_BITS (_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \ _PAGE_WRITETHRU | _PAGE_4K_PFN | \ - _PAGE_USER | _PAGE_ACCESSED | \ - _PAGE_RW | _PAGE_DIRTY | _PAGE_EXEC | \ + _PAGE_USER | _PAGE_ACCESSED | _PAGE_READ |\ + _PAGE_WRITE | _PAGE_DIRTY | _PAGE_EXEC | \ _PAGE_SOFT_DIRTY) /* * We define 2 sets of base prot bits, one for basic pages (ie, @@ -171,10 +173,12 @@ #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) +#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ) +#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ| \ + _PAGE_EXEC) +#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ) +#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ| \ + _PAGE_EXEC) #define __P000 PAGE_NONE #define __P001 PAGE_READONLY @@ -296,19 +300,19 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - if ((pte_val(*ptep) & _PAGE_RW) == 0) + if ((pte_val(*ptep) & _PAGE_WRITE) == 0) return; - pte_update(mm, addr, ptep, _PAGE_RW, 0, 0); + pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 0); } static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - if ((pte_val(*ptep) & _PAGE_RW) == 0) + if ((pte_val(*ptep) & _PAGE_WRITE) == 0) return; - pte_update(mm, addr, ptep, _PAGE_RW, 0, 1); + pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 1); } /* @@ -349,7 +353,7 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry) { __be64 old, tmp, val, mask; - mask = cpu_to_be64(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | + mask = cpu_to_be64(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC | _PAGE_SOFT_DIRTY); val = pte_raw(entry) & mask; @@ -384,7 +388,7 @@ static inline unsigned long pgd_page_vaddr(pgd_t pgd) /* Generic accessors to PTE bits */ -static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);} +static inline int 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); } @@ -445,7 +449,7 @@ static inline unsigned long pte_pfn(pte_t pte) /* 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_mkclean(pte_t pte) @@ -460,6 +464,9 @@ static inline pte_t pte_mkold(pte_t pte) static inline pte_t pte_mkwrite(pte_t pte) { + /* + * write implies read, hence set both + */ return __pte(pte_val(pte) | _PAGE_RW); } diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h index 1ec67b043065..9f5dea58b0db 100644 --- a/arch/powerpc/include/asm/pte-common.h +++ b/arch/powerpc/include/asm/pte-common.h @@ -198,3 +198,8 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void); /* Advertise support for _PAGE_SPECIAL */ #define __HAVE_ARCH_PTE_SPECIAL +#ifndef _PAGE_READ +/* if not defined, we should not find _PAGE_WRITE too */ +#define _PAGE_READ 0 +#define _PAGE_WRITE _PAGE_RW +#endif diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c index dbd3133a8562..491b7d137cd8 100644 --- a/arch/powerpc/mm/hash64_4k.c +++ b/arch/powerpc/mm/hash64_4k.c @@ -45,7 +45,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid, * also add _PAGE_COMBO */ new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED; - if (access & _PAGE_RW) + if (access & _PAGE_WRITE) new_pte |= _PAGE_DIRTY; } while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte))); diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c index 292f40705674..2d3472173d79 100644 --- a/arch/powerpc/mm/hash64_64k.c +++ b/arch/powerpc/mm/hash64_64k.c @@ -77,7 +77,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid, * also add _PAGE_COMBO */ new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED | _PAGE_COMBO; - if (access & _PAGE_RW) + if (access & _PAGE_WRITE) new_pte |= _PAGE_DIRTY; } while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte))); @@ -251,7 +251,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access, * a write access. */ new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED; - if (access & _PAGE_RW) + if (access & _PAGE_WRITE) new_pte |= _PAGE_DIRTY; } while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte))); diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index 7635b1c6b5da..ed190e42bbc5 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -175,8 +175,9 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags) * or PP=0x3 for read-only (including writeable but clean pages). */ if (pteflags & _PAGE_USER) { - rflags |= 0x2; - if (!((pteflags & _PAGE_RW) && (pteflags & _PAGE_DIRTY))) + if (pteflags & _PAGE_RWX) + rflags |= 0x2; + if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY))) rflags |= 0x1; } /* @@ -1209,7 +1210,7 @@ EXPORT_SYMBOL_GPL(hash_page); int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap, unsigned long dsisr) { - unsigned long access = _PAGE_PRESENT; + unsigned long access = _PAGE_PRESENT | _PAGE_READ; unsigned long flags = 0; struct mm_struct *mm = current->mm; @@ -1220,7 +1221,7 @@ int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap, flags |= HPTE_NOHPTE_UPDATE; if (dsisr & DSISR_ISSTORE) - access |= _PAGE_RW; + access |= _PAGE_WRITE; /* * We need to set the _PAGE_USER bit if MSR_PR is set or if we are * accessing a userspace segment (even from the kernel). We assume diff --git a/arch/powerpc/mm/hugepage-hash64.c b/arch/powerpc/mm/hugepage-hash64.c index 92c3c1858707..b4b6668d1b24 100644 --- a/arch/powerpc/mm/hugepage-hash64.c +++ b/arch/powerpc/mm/hugepage-hash64.c @@ -47,7 +47,7 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid, * a write access */ new_pmd = old_pmd | _PAGE_BUSY | _PAGE_ACCESSED; - if (access & _PAGE_RW) + if (access & _PAGE_WRITE) new_pmd |= _PAGE_DIRTY; } while (!pmd_xchg(pmdp, __pmd(old_pmd), __pmd(new_pmd))); diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c index 9c0518761279..cdca743cdaf1 100644 --- a/arch/powerpc/mm/hugetlbpage-hash64.c +++ b/arch/powerpc/mm/hugetlbpage-hash64.c @@ -55,7 +55,7 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid, /* Try to lock the PTE, add ACCESSED and DIRTY if it was * a write access */ new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED; - if (access & _PAGE_RW) + if (access & _PAGE_WRITE) new_pte |= _PAGE_DIRTY; } while(!pte_xchg(ptep, __pte(old_pte), __pte(new_pte))); diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index d991b9e80dbb..0bf269b00de9 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -1003,9 +1003,9 @@ int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr, end = pte_end; pte = READ_ONCE(*ptep); - mask = _PAGE_PRESENT | _PAGE_USER; + mask = _PAGE_PRESENT | _PAGE_USER | _PAGE_READ; if (write) - mask |= _PAGE_RW; + mask |= _PAGE_WRITE; if ((pte_val(pte) & mask) != mask) return 0; diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index de37ff445362..ef7b922c655c 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -177,8 +177,8 @@ void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, * _PAGE_PRESENT, but we can be sure that it is not in hpte. * Hence we can use set_pte_at for them. */ - VM_WARN_ON((pte_val(*ptep) & (_PAGE_PRESENT | _PAGE_USER)) == - (_PAGE_PRESENT | _PAGE_USER)); + VM_WARN_ON(pte_present(*ptep) && !pte_protnone(*ptep)); + /* * Add the pte bit when tryint set a pte */ diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index 494fc111ef90..16bc751f10df 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -277,7 +277,7 @@ void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, void *caller = __builtin_return_address(0); /* writeable implies dirty for kernel addresses */ - if (flags & _PAGE_RW) + if (flags & _PAGE_WRITE) flags |= _PAGE_DIRTY; /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */ @@ -676,8 +676,7 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd) { #ifdef CONFIG_DEBUG_VM - WARN_ON((pmd_val(*pmdp) & (_PAGE_PRESENT | _PAGE_USER)) == - (_PAGE_PRESENT | _PAGE_USER)); + WARN_ON(pte_present(pmd_pte(*pmdp)) && !pte_protnone(pmd_pte(*pmdp))); assert_spin_locked(&mm->page_table_lock); WARN_ON(!pmd_trans_huge(pmd)); #endif diff --git a/arch/powerpc/platforms/cell/spu_base.c b/arch/powerpc/platforms/cell/spu_base.c index 3ede04ffdeea..3cbe38fad609 100644 --- a/arch/powerpc/platforms/cell/spu_base.c +++ b/arch/powerpc/platforms/cell/spu_base.c @@ -197,7 +197,7 @@ static int __spu_trap_data_map(struct spu *spu, unsigned long ea, u64 dsisr) (REGION_ID(ea) != USER_REGION_ID)) { spin_unlock(&spu->register_lock); - ret = hash_page(ea, _PAGE_PRESENT, 0x300, dsisr); + ret = hash_page(ea, _PAGE_PRESENT | _PAGE_READ, 0x300, dsisr); spin_lock(&spu->register_lock); if (!ret) { diff --git a/arch/powerpc/platforms/cell/spufs/fault.c b/arch/powerpc/platforms/cell/spufs/fault.c index d98f845ac777..c3a3bf1745b7 100644 --- a/arch/powerpc/platforms/cell/spufs/fault.c +++ b/arch/powerpc/platforms/cell/spufs/fault.c @@ -141,8 +141,8 @@ int spufs_handle_class1(struct spu_context *ctx) /* we must not hold the lock when entering copro_handle_mm_fault */ spu_release(ctx); - access = (_PAGE_PRESENT | _PAGE_USER); - access |= (dsisr & MFC_DSISR_ACCESS_PUT) ? _PAGE_RW : 0UL; + access = (_PAGE_PRESENT | _PAGE_READ | _PAGE_USER); + access |= (dsisr & MFC_DSISR_ACCESS_PUT) ? _PAGE_WRITE : 0UL; local_irq_save(flags); ret = hash_page(ea, access, 0x300, dsisr); local_irq_restore(flags); diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c index 9a236543da23..0feeacedcef1 100644 --- a/drivers/misc/cxl/fault.c +++ b/drivers/misc/cxl/fault.c @@ -149,9 +149,9 @@ static void cxl_handle_page_fault(struct cxl_context *ctx, * update_mmu_cache() will not have loaded the hash since current->trap * is not a 0x400 or 0x300, so just call hash_page_mm() here. */ - access = _PAGE_PRESENT; + access = _PAGE_PRESENT | _PAGE_READ; if (dsisr & CXL_PSL_DSISR_An_S) - access |= _PAGE_RW; + access |= _PAGE_WRITE; if ((!ctx->kernel) || (REGION_ID(dar) == USER_REGION_ID)) access |= _PAGE_USER;