From 30bda41aba4efb2370c97e2cbe7385de93ccc372 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Fri, 29 Apr 2016 23:25:38 +1000 Subject: [PATCH] powerpc/mm: Drop WIMG in favour of new constants PowerISA 3.0 introduces two pte bits with the below meaning for radix: 00 -> Normal Memory 01 -> Strong Access Order (SAO) 10 -> Non idempotent I/O (Cache inhibited and guarded) 11 -> Tolerant I/O (Cache inhibited) We drop the existing WIMG bits in the Linux page table in favour of the above constants. We loose _PAGE_WRITETHRU with this conversion. We only use writethru via pgprot_cached_wthru() which is used by fbdev/controlfb.c which is Apple control display and also PPC32. With respect to _PAGE_COHERENCE, we have been marking hpte always coherent for some time now. htab_convert_pte_flags() always added HPTE_R_M. NOTE: KVM changes need closer review. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/book3s/64/hash.h | 70 ++++++++++------------- arch/powerpc/include/asm/kvm_book3s_64.h | 27 ++++----- arch/powerpc/kvm/book3s_64_mmu_hv.c | 11 ++-- arch/powerpc/kvm/book3s_hv_rm_mmu.c | 12 ++-- arch/powerpc/mm/hash64_64k.c | 2 +- arch/powerpc/mm/hash_utils_64.c | 18 +++--- arch/powerpc/mm/pgtable.c | 8 +-- arch/powerpc/mm/pgtable_64.c | 4 -- arch/powerpc/platforms/pseries/lpar.c | 4 -- 9 files changed, 66 insertions(+), 90 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h index eb224792095f..eee951fd6a33 100644 --- a/arch/powerpc/include/asm/book3s/64/hash.h +++ b/arch/powerpc/include/asm/book3s/64/hash.h @@ -21,11 +21,9 @@ #define _PAGE_RW (_PAGE_READ | _PAGE_WRITE) #define _PAGE_RWX (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC) #define _PAGE_PRIVILEGED 0x00008 /* kernel access only */ -#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 */ -#define _PAGE_COHERENT 0x0 -#define _PAGE_NO_CACHE 0x00020 /* I: cache inhibit */ -#define _PAGE_WRITETHRU 0x00040 /* W: cache write-through */ +#define _PAGE_SAO 0x00010 /* Strong access order */ +#define _PAGE_NON_IDEMPOTENT 0x00020 /* non idempotent memory */ +#define _PAGE_TOLERANT 0x00030 /* tolerant memory, cache inhibited */ #define _PAGE_DIRTY 0x00080 /* C: page changed */ #define _PAGE_ACCESSED 0x00100 /* R: page referenced */ #define _PAGE_SPECIAL 0x00400 /* software: special page */ @@ -43,7 +41,12 @@ #define _PAGE_HASHPTE (1ul << 61) /* PTE has associated HPTE */ #define _PAGE_PTE (1ul << 62) /* distinguishes PTEs from pointers */ #define _PAGE_PRESENT (1ul << 63) /* pte contains a translation */ - +/* + * Drivers request for cache inhibited pte mapping using _PAGE_NO_CACHE + * Instead of fixing all of them, add an alternate define which + * maps CI pte mapping. + */ +#define _PAGE_NO_CACHE _PAGE_TOLERANT /* * We need to differentiate between explicit huge page and THP huge * page, since THP huge page also need to track real subpage details @@ -126,9 +129,6 @@ #define _PAGE_KERNEL_RWX (_PAGE_PRIVILEGED | _PAGE_DIRTY | \ _PAGE_RW | _PAGE_EXEC) -/* Strong Access Ordering */ -#define _PAGE_SAO (_PAGE_WRITETHRU | _PAGE_NO_CACHE | _PAGE_COHERENT) - /* No page size encoding in the linux PTE */ #define _PAGE_PSIZE 0 @@ -147,10 +147,9 @@ /* * Mask of bits returned by pte_pgprot() */ -#define PAGE_PROT_BITS (_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \ - _PAGE_WRITETHRU | _PAGE_4K_PFN | \ - _PAGE_PRIVILEGED | _PAGE_ACCESSED | _PAGE_READ |\ - _PAGE_WRITE | _PAGE_DIRTY | _PAGE_EXEC | \ +#define PAGE_PROT_BITS (_PAGE_SAO | _PAGE_NON_IDEMPOTENT | _PAGE_TOLERANT | \ + _PAGE_4K_PFN | _PAGE_PRIVILEGED | _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, @@ -159,7 +158,7 @@ * the processor might need it for DMA coherency. */ #define _PAGE_BASE_NC (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_PSIZE) -#define _PAGE_BASE (_PAGE_BASE_NC | _PAGE_COHERENT) +#define _PAGE_BASE (_PAGE_BASE_NC) /* Permission masks used to generate the __P and __S table, * @@ -200,9 +199,9 @@ /* 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) + _PAGE_TOLERANT) #define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \ - _PAGE_NO_CACHE | _PAGE_GUARDED) + _PAGE_NON_IDEMPOTENT) #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) @@ -509,45 +508,26 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, *ptep = pte; } -/* - * Macro to mark a page protection value as "uncacheable". - */ - -#define _PAGE_CACHE_CTL (_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \ - _PAGE_WRITETHRU) +#define _PAGE_CACHE_CTL (_PAGE_NON_IDEMPOTENT | _PAGE_TOLERANT) #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); + _PAGE_NON_IDEMPOTENT); } #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); + _PAGE_TOLERANT); } #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); + return __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL)); } #define pgprot_writecombine pgprot_writecombine @@ -555,6 +535,18 @@ static inline pgprot_t pgprot_writecombine(pgprot_t prot) { return pgprot_noncached_wc(prot); } +/* + * check a pte mapping have cache inhibited property + */ +static inline bool pte_ci(pte_t pte) +{ + unsigned long pte_v = pte_val(pte); + + if (((pte_v & _PAGE_CACHE_CTL) == _PAGE_TOLERANT) || + ((pte_v & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT)) + return true; + return false; +} #ifdef CONFIG_TRANSPARENT_HUGEPAGE extern void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr, diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h index 42da513fec2d..3c380c247d4e 100644 --- a/arch/powerpc/include/asm/kvm_book3s_64.h +++ b/arch/powerpc/include/asm/kvm_book3s_64.h @@ -276,19 +276,24 @@ static inline unsigned long hpte_make_readonly(unsigned long ptel) return ptel; } -static inline int hpte_cache_flags_ok(unsigned long ptel, unsigned long io_type) +static inline bool hpte_cache_flags_ok(unsigned long hptel, bool is_ci) { - unsigned int wimg = ptel & HPTE_R_WIMG; + unsigned int wimg = hptel & HPTE_R_WIMG; /* Handle SAO */ if (wimg == (HPTE_R_W | HPTE_R_I | HPTE_R_M) && cpu_has_feature(CPU_FTR_ARCH_206)) wimg = HPTE_R_M; - if (!io_type) + if (!is_ci) return wimg == HPTE_R_M; - - return (wimg & (HPTE_R_W | HPTE_R_I)) == io_type; + /* + * if host is mapped cache inhibited, make sure hptel also have + * cache inhibited. + */ + if (wimg & HPTE_R_W) /* FIXME!! is this ok for all guest. ? */ + return false; + return !!(wimg & HPTE_R_I); } /* @@ -325,18 +330,6 @@ static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing) return new_pte; } - -/* Return HPTE cache control bits corresponding to Linux pte bits */ -static inline unsigned long hpte_cache_bits(unsigned long pte_val) -{ -#if _PAGE_NO_CACHE == HPTE_R_I && _PAGE_WRITETHRU == HPTE_R_W - return pte_val & (HPTE_R_W | HPTE_R_I); -#else - return ((pte_val & _PAGE_NO_CACHE) ? HPTE_R_I : 0) + - ((pte_val & _PAGE_WRITETHRU) ? HPTE_R_W : 0); -#endif -} - static inline bool hpte_read_permission(unsigned long pp, unsigned long key) { if (key) diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index c7b78d8336b2..05f09ae82587 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -447,7 +447,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, struct revmap_entry *rev; struct page *page, *pages[1]; long index, ret, npages; - unsigned long is_io; + bool is_ci; unsigned int writing, write_ok; struct vm_area_struct *vma; unsigned long rcbits; @@ -503,7 +503,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, smp_rmb(); ret = -EFAULT; - is_io = 0; + is_ci = false; pfn = 0; page = NULL; pte_size = PAGE_SIZE; @@ -521,7 +521,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, pfn = vma->vm_pgoff + ((hva - vma->vm_start) >> PAGE_SHIFT); pte_size = psize; - is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot)); + is_ci = pte_ci(__pte((pgprot_val(vma->vm_page_prot)))); write_ok = vma->vm_flags & VM_WRITE; } up_read(¤t->mm->mmap_sem); @@ -558,10 +558,9 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, goto out_put; /* Check WIMG vs. the actual page we're accessing */ - if (!hpte_cache_flags_ok(r, is_io)) { - if (is_io) + if (!hpte_cache_flags_ok(r, is_ci)) { + if (is_ci) goto out_put; - /* * Allow guest to map emulated device memory as * uncacheable, but actually make it cacheable. diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 4cb8db05f3e5..99b4e9d5dd23 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -175,7 +175,7 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags, unsigned long g_ptel; struct kvm_memory_slot *memslot; unsigned hpage_shift; - unsigned long is_io; + bool is_ci; unsigned long *rmap; pte_t *ptep; unsigned int writing; @@ -199,7 +199,7 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags, gfn = gpa >> PAGE_SHIFT; memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn); pa = 0; - is_io = ~0ul; + is_ci = false; rmap = NULL; if (!(memslot && !(memslot->flags & KVM_MEMSLOT_INVALID))) { /* Emulated MMIO - mark this with key=31 */ @@ -250,7 +250,7 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags, if (writing && !pte_write(pte)) /* make the actual HPTE be read-only */ ptel = hpte_make_readonly(ptel); - is_io = hpte_cache_bits(pte_val(pte)); + is_ci = pte_ci(pte); pa = pte_pfn(pte) << PAGE_SHIFT; pa |= hva & (host_pte_size - 1); pa |= gpa & ~PAGE_MASK; @@ -267,9 +267,9 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags, else pteh |= HPTE_V_ABSENT; - /* Check WIMG */ - if (is_io != ~0ul && !hpte_cache_flags_ok(ptel, is_io)) { - if (is_io) + /*If we had host pte mapping then Check WIMG */ + if (ptep && !hpte_cache_flags_ok(ptel, is_ci)) { + if (is_ci) return H_PARAMETER; /* * Allow guest to map emulated device memory as diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c index e7782862362b..675331083728 100644 --- a/arch/powerpc/mm/hash64_64k.c +++ b/arch/powerpc/mm/hash64_64k.c @@ -244,7 +244,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access, * If so, bail out and refault as a 4k page */ if (!mmu_has_feature(MMU_FTR_CI_LARGE_PAGE) && - unlikely(old_pte & _PAGE_NO_CACHE)) + unlikely(pte_ci(pte))) return 0; /* * Try to lock the PTE, add ACCESSED and DIRTY if it was diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index 38ed869c119e..eb928d86ce01 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -192,12 +192,13 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags) /* * Add in WIG bits */ - if (pteflags & _PAGE_WRITETHRU) - rflags |= HPTE_R_W; - if (pteflags & _PAGE_NO_CACHE) + + if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_TOLERANT) rflags |= HPTE_R_I; - if (pteflags & _PAGE_GUARDED) - rflags |= HPTE_R_G; + if ((pteflags & _PAGE_CACHE_CTL ) == _PAGE_NON_IDEMPOTENT) + rflags |= (HPTE_R_I | HPTE_R_G); + if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_SAO) + rflags |= (HPTE_R_I | HPTE_R_W); return rflags; } @@ -1142,8 +1143,7 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea, /* If this PTE is non-cacheable and we have restrictions on * using non cacheable large pages, then we switch to 4k */ - if (mmu_ci_restrictions && psize == MMU_PAGE_64K && - (pte_val(*ptep) & _PAGE_NO_CACHE)) { + if (mmu_ci_restrictions && psize == MMU_PAGE_64K && pte_ci(*ptep)) { if (user_region) { demote_segment_4k(mm, ea); psize = MMU_PAGE_4K; @@ -1297,13 +1297,13 @@ void hash_preload(struct mm_struct *mm, unsigned long ea, WARN_ON(hugepage_shift); #ifdef CONFIG_PPC_64K_PAGES - /* If either _PAGE_4K_PFN or _PAGE_NO_CACHE is set (and we are on + /* If either _PAGE_4K_PFN or cache inhibited is set (and we are on * a 64K kernel), then we don't preload, hash_page() will take * care of it once we actually try to access the page. * That way we don't have to duplicate all of the logic for segment * page size demotion here */ - if (pte_val(*ptep) & (_PAGE_4K_PFN | _PAGE_NO_CACHE)) + if ((pte_val(*ptep) & _PAGE_4K_PFN) || pte_ci(*ptep)) goto out_exit; #endif /* CONFIG_PPC_64K_PAGES */ diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index 125fb4b54445..db277b6d8e8b 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -38,16 +38,16 @@ static inline int is_exec_fault(void) /* We only try to do i/d cache coherency on stuff that looks like * reasonably "normal" PTEs. We currently require a PTE to be present - * and we avoid _PAGE_SPECIAL and _PAGE_NO_CACHE. We also only do that + * and we avoid _PAGE_SPECIAL and cache inhibited pte. We also only do that * on userspace PTEs */ static inline int pte_looks_normal(pte_t pte) { #if defined(CONFIG_PPC_BOOK3S_64) - if ((pte_val(pte) & - (_PAGE_PRESENT | _PAGE_SPECIAL | _PAGE_NO_CACHE)) == - _PAGE_PRESENT) { + if ((pte_val(pte) & (_PAGE_PRESENT | _PAGE_SPECIAL)) == _PAGE_PRESENT) { + if (pte_ci(pte)) + return 0; if (pte_user(pte)) return 1; } diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index ea60a24c17a6..b3040b4535da 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -167,10 +167,6 @@ void __iomem * __ioremap_at(phys_addr_t pa, void *ea, unsigned long size, if ((flags & _PAGE_PRESENT) == 0) flags |= pgprot_val(PAGE_KERNEL); - /* Non-cacheable page cannot be coherent */ - if (flags & _PAGE_NO_CACHE) - flags &= ~_PAGE_COHERENT; - /* We don't support the 4K PFN hack with ioremap */ if (flags & _PAGE_4K_PFN) return NULL; diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index 2415a0d31f8f..0d4608990702 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -152,10 +152,6 @@ static long pSeries_lpar_hpte_insert(unsigned long hpte_group, /* Exact = 0 */ flags = 0; - /* Make pHyp happy */ - if ((rflags & _PAGE_NO_CACHE) && !(rflags & _PAGE_WRITETHRU)) - hpte_r &= ~HPTE_R_M; - if (firmware_has_feature(FW_FEATURE_XCMO) && !(hpte_r & HPTE_R_N)) flags |= H_COALESCE_CAND; -- 2.30.2