diff options
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/pgtable.h | 24 | ||||
| -rw-r--r-- | arch/powerpc/mm/pgtable-hash64.c | 358 | ||||
| -rw-r--r-- | arch/powerpc/mm/pgtable_64.c | 359 |
3 files changed, 369 insertions, 372 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 9175a688e70f..dfdd1f4e4cf0 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -777,18 +777,6 @@ static inline void vmemmap_remove_mapping(unsigned long start, #endif struct page *realmode_pfn_to_page(unsigned long pfn); -#ifdef CONFIG_TRANSPARENT_HUGEPAGE -extern pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot); -extern pmd_t mk_pmd(struct page *page, pgprot_t pgprot); -extern pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot); -extern void set_pmd_at(struct mm_struct *mm, unsigned long addr, - pmd_t *pmdp, pmd_t pmd); -extern void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr, - pmd_t *pmd); -extern int has_transparent_hugepage(void); -#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ - - static inline pte_t pmd_pte(pmd_t pmd) { return __pte(pmd_val(pmd)); @@ -803,7 +791,6 @@ static inline pte_t *pmdp_ptep(pmd_t *pmd) { return (pte_t *)pmd; } - #define pmd_pfn(pmd) pte_pfn(pmd_pte(pmd)) #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd)) #define pmd_young(pmd) pte_young(pmd_pte(pmd)) @@ -830,6 +817,16 @@ static inline int pmd_protnone(pmd_t pmd) #define __HAVE_ARCH_PMD_WRITE #define pmd_write(pmd) pte_write(pmd_pte(pmd)) +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +extern pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot); +extern pmd_t mk_pmd(struct page *page, pgprot_t pgprot); +extern pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot); +extern void set_pmd_at(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, pmd_t pmd); +extern void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr, + pmd_t *pmd); +extern int has_transparent_hugepage(void); + static inline pmd_t pmd_mkhuge(pmd_t pmd) { return __pmd(pmd_val(pmd) | (_PAGE_PTE | H_PAGE_THP_HUGE)); @@ -878,5 +875,6 @@ static inline int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl, */ return true; } +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif /* __ASSEMBLY__ */ #endif /* _ASM_POWERPC_BOOK3S_64_PGTABLE_H_ */ diff --git a/arch/powerpc/mm/pgtable-hash64.c b/arch/powerpc/mm/pgtable-hash64.c index 64975ebfc50b..9699a1ccedb5 100644 --- a/arch/powerpc/mm/pgtable-hash64.c +++ b/arch/powerpc/mm/pgtable-hash64.c @@ -15,6 +15,9 @@ #include "mmu_decl.h" +#define CREATE_TRACE_POINTS +#include <trace/events/thp.h> + #ifdef CONFIG_SPARSEMEM_VMEMMAP /* * On hash-based CPUs, the vmemmap is bolted in the hash table. @@ -93,3 +96,358 @@ int hash__map_kernel_page(unsigned long ea, unsigned long pa, unsigned long flag smp_wmb(); return 0; } + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + +/* + * This is called when relaxing access to a hugepage. It's also called in the page + * fault path when we don't hit any of the major fault cases, ie, a minor + * update of _PAGE_ACCESSED, _PAGE_DIRTY, etc... The generic code will have + * handled those two for us, we additionally deal with missing execute + * permission here on some processors + */ +int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp, pmd_t entry, int dirty) +{ + int changed; +#ifdef CONFIG_DEBUG_VM + WARN_ON(!pmd_trans_huge(*pmdp)); + assert_spin_locked(&vma->vm_mm->page_table_lock); +#endif + changed = !pmd_same(*(pmdp), entry); + if (changed) { + __ptep_set_access_flags(pmdp_ptep(pmdp), pmd_pte(entry)); + /* + * Since we are not supporting SW TLB systems, we don't + * have any thing similar to flush_tlb_page_nohash() + */ + } + return changed; +} + +unsigned long pmd_hugepage_update(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, unsigned long clr, + unsigned long set) +{ + __be64 old_be, tmp; + unsigned long old; + +#ifdef CONFIG_DEBUG_VM + WARN_ON(!pmd_trans_huge(*pmdp)); + assert_spin_locked(&mm->page_table_lock); +#endif + + __asm__ __volatile__( + "1: ldarx %0,0,%3\n\ + and. %1,%0,%6\n\ + bne- 1b \n\ + andc %1,%0,%4 \n\ + or %1,%1,%7\n\ + stdcx. %1,0,%3 \n\ + bne- 1b" + : "=&r" (old_be), "=&r" (tmp), "=m" (*pmdp) + : "r" (pmdp), "r" (cpu_to_be64(clr)), "m" (*pmdp), + "r" (cpu_to_be64(H_PAGE_BUSY)), "r" (cpu_to_be64(set)) + : "cc" ); + + old = be64_to_cpu(old_be); + + trace_hugepage_update(addr, old, clr, set); + if (old & H_PAGE_HASHPTE) + hpte_do_hugepage_flush(mm, addr, pmdp, old); + return old; +} + +pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp) +{ + pmd_t pmd; + + VM_BUG_ON(address & ~HPAGE_PMD_MASK); + VM_BUG_ON(pmd_trans_huge(*pmdp)); + + pmd = *pmdp; + pmd_clear(pmdp); + /* + * Wait for all pending hash_page to finish. This is needed + * in case of subpage collapse. When we collapse normal pages + * to hugepage, we first clear the pmd, then invalidate all + * the PTE entries. The assumption here is that any low level + * page fault will see a none pmd and take the slow path that + * will wait on mmap_sem. But we could very well be in a + * hash_page with local ptep pointer value. Such a hash page + * can result in adding new HPTE entries for normal subpages. + * That means we could be modifying the page content as we + * copy them to a huge page. So wait for parallel hash_page + * to finish before invalidating HPTE entries. We can do this + * by sending an IPI to all the cpus and executing a dummy + * function there. + */ + kick_all_cpus_sync(); + /* + * Now invalidate the hpte entries in the range + * covered by pmd. This make sure we take a + * fault and will find the pmd as none, which will + * result in a major fault which takes mmap_sem and + * hence wait for collapse to complete. Without this + * the __collapse_huge_page_copy can result in copying + * the old content. + */ + flush_tlb_pmd_range(vma->vm_mm, &pmd, address); + return pmd; +} + +/* + * We currently remove entries from the hashtable regardless of whether + * the entry was young or dirty. + * + * We should be more intelligent about this but for the moment we override + * these functions and force a tlb flush unconditionally + */ +int pmdp_test_and_clear_young(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp) +{ + return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp); +} + +/* + * We want to put the pgtable in pmd and use pgtable for tracking + * the base page size hptes + */ +void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, + pgtable_t pgtable) +{ + pgtable_t *pgtable_slot; + assert_spin_locked(&mm->page_table_lock); + /* + * we store the pgtable in the second half of PMD + */ + pgtable_slot = (pgtable_t *)pmdp + PTRS_PER_PMD; + *pgtable_slot = pgtable; + /* + * expose the deposited pgtable to other cpus. + * before we set the hugepage PTE at pmd level + * hash fault code looks at the deposted pgtable + * to store hash index values. + */ + smp_wmb(); +} + +pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) +{ + pgtable_t pgtable; + pgtable_t *pgtable_slot; + + assert_spin_locked(&mm->page_table_lock); + pgtable_slot = (pgtable_t *)pmdp + PTRS_PER_PMD; + pgtable = *pgtable_slot; + /* + * Once we withdraw, mark the entry NULL. + */ + *pgtable_slot = NULL; + /* + * We store HPTE information in the deposited PTE fragment. + * zero out the content on withdraw. + */ + memset(pgtable, 0, PTE_FRAG_SIZE); + return pgtable; +} + +void pmdp_huge_split_prepare(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp) +{ + VM_BUG_ON(address & ~HPAGE_PMD_MASK); + VM_BUG_ON(REGION_ID(address) != USER_REGION_ID); + + /* + * We can't mark the pmd none here, because that will cause a race + * against exit_mmap. We need to continue mark pmd TRANS HUGE, while + * we spilt, but at the same time we wan't rest of the ppc64 code + * not to insert hash pte on this, because we will be modifying + * the deposited pgtable in the caller of this function. Hence + * clear the _PAGE_USER so that we move the fault handling to + * higher level function and that will serialize against ptl. + * We need to flush existing hash pte entries here even though, + * the translation is still valid, because we will withdraw + * pgtable_t after this. + */ + pmd_hugepage_update(vma->vm_mm, address, pmdp, 0, _PAGE_PRIVILEGED); +} + + +/* + * set a new huge pmd. We should not be called for updating + * an existing pmd entry. That should go via pmd_hugepage_update. + */ +void set_pmd_at(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, pmd_t pmd) +{ +#ifdef CONFIG_DEBUG_VM + 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 + trace_hugepage_set_pmd(addr, pmd_val(pmd)); + return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); +} + +/* + * We use this to invalidate a pmdp entry before switching from a + * hugepte to regular pmd entry. + */ +void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp) +{ + pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, 0); + + /* + * This ensures that generic code that rely on IRQ disabling + * to prevent a parallel THP split work as expected. + */ + kick_all_cpus_sync(); +} + +/* + * A linux hugepage PMD was changed and the corresponding hash table entries + * neesd to be flushed. + */ +void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, unsigned long old_pmd) +{ + int ssize; + unsigned int psize; + unsigned long vsid; + unsigned long flags = 0; + const struct cpumask *tmp; + + /* get the base page size,vsid and segment size */ +#ifdef CONFIG_DEBUG_VM + psize = get_slice_psize(mm, addr); + BUG_ON(psize == MMU_PAGE_16M); +#endif + if (old_pmd & H_PAGE_COMBO) + psize = MMU_PAGE_4K; + else + psize = MMU_PAGE_64K; + + if (!is_kernel_addr(addr)) { + ssize = user_segment_size(addr); + vsid = get_vsid(mm->context.id, addr, ssize); + WARN_ON(vsid == 0); + } else { + vsid = get_kernel_vsid(addr, mmu_kernel_ssize); + ssize = mmu_kernel_ssize; + } + + tmp = cpumask_of(smp_processor_id()); + if (cpumask_equal(mm_cpumask(mm), tmp)) + flags |= HPTE_LOCAL_UPDATE; + + return flush_hash_hugepage(vsid, addr, pmdp, psize, ssize, flags); +} + +static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot) +{ + return __pmd(pmd_val(pmd) | pgprot_val(pgprot)); +} + +pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot) +{ + unsigned long pmdv; + + pmdv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK; + return pmd_set_protbits(__pmd(pmdv), pgprot); +} + +pmd_t mk_pmd(struct page *page, pgprot_t pgprot) +{ + return pfn_pmd(page_to_pfn(page), pgprot); +} + +pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) +{ + unsigned long pmdv; + + pmdv = pmd_val(pmd); + pmdv &= _HPAGE_CHG_MASK; + return pmd_set_protbits(__pmd(pmdv), newprot); +} + +/* + * This is called at the end of handling a user page fault, when the + * fault has been handled by updating a HUGE PMD entry in the linux page tables. + * We use it to preload an HPTE into the hash table corresponding to + * the updated linux HUGE PMD entry. + */ +void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr, + pmd_t *pmd) +{ + return; +} + +pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, + unsigned long addr, pmd_t *pmdp) +{ + pmd_t old_pmd; + pgtable_t pgtable; + unsigned long old; + pgtable_t *pgtable_slot; + + old = pmd_hugepage_update(mm, addr, pmdp, ~0UL, 0); + old_pmd = __pmd(old); + /* + * We have pmd == none and we are holding page_table_lock. + * So we can safely go and clear the pgtable hash + * index info. + */ + pgtable_slot = (pgtable_t *)pmdp + PTRS_PER_PMD; + pgtable = *pgtable_slot; + /* + * Let's zero out old valid and hash index details + * hash fault look at them. + */ + memset(pgtable, 0, PTE_FRAG_SIZE); + /* + * Serialize against find_linux_pte_or_hugepte which does lock-less + * lookup in page tables with local interrupts disabled. For huge pages + * it casts pmd_t to pte_t. Since format of pte_t is different from + * pmd_t we want to prevent transit from pmd pointing to page table + * to pmd pointing to huge page (and back) while interrupts are disabled. + * We clear pmd to possibly replace it with page table pointer in + * different code paths. So make sure we wait for the parallel + * find_linux_pte_or_hugepage to finish. + */ + kick_all_cpus_sync(); + return old_pmd; +} + +int has_transparent_hugepage(void) +{ + + if (!mmu_has_feature(MMU_FTR_16M_PAGE)) + return 0; + /* + * We support THP only if PMD_SIZE is 16MB. + */ + if (mmu_psize_defs[MMU_PAGE_16M].shift != PMD_SHIFT) + return 0; + /* + * We need to make sure that we support 16MB hugepage in a segement + * with base page size 64K or 4K. We only enable THP with a PAGE_SIZE + * of 64K. + */ + /* + * If we have 64K HPTE, we will be using that by default + */ + if (mmu_psize_defs[MMU_PAGE_64K].shift && + (mmu_psize_defs[MMU_PAGE_64K].penc[MMU_PAGE_16M] == -1)) + return 0; + /* + * Ok we only have 4K HPTE + */ + if (mmu_psize_defs[MMU_PAGE_4K].penc[MMU_PAGE_16M] == -1) + return 0; + + return 1; +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index 95df08e73559..e009e0604a8a 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -55,9 +55,6 @@ #include "mmu_decl.h" -#define CREATE_TRACE_POINTS -#include <trace/events/thp.h> - #ifdef CONFIG_PPC_STD_MMU_64 #if TASK_SIZE_USER64 > (1UL << (ESID_BITS + SID_SHIFT)) #error TASK_SIZE_USER64 exceeds user VSID range @@ -435,359 +432,3 @@ void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift) } } #endif - -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - -/* - * This is called when relaxing access to a hugepage. It's also called in the page - * fault path when we don't hit any of the major fault cases, ie, a minor - * update of _PAGE_ACCESSED, _PAGE_DIRTY, etc... The generic code will have - * handled those two for us, we additionally deal with missing execute - * permission here on some processors - */ -int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address, - pmd_t *pmdp, pmd_t entry, int dirty) -{ - int changed; -#ifdef CONFIG_DEBUG_VM - WARN_ON(!pmd_trans_huge(*pmdp)); - assert_spin_locked(&vma->vm_mm->page_table_lock); -#endif - changed = !pmd_same(*(pmdp), entry); - if (changed) { - __ptep_set_access_flags(pmdp_ptep(pmdp), pmd_pte(entry)); - /* - * Since we are not supporting SW TLB systems, we don't - * have any thing similar to flush_tlb_page_nohash() - */ - } - return changed; -} - -unsigned long pmd_hugepage_update(struct mm_struct *mm, unsigned long addr, - pmd_t *pmdp, unsigned long clr, - unsigned long set) -{ - - __be64 old_be, tmp; - unsigned long old; - -#ifdef CONFIG_DEBUG_VM - WARN_ON(!pmd_trans_huge(*pmdp)); - assert_spin_locked(&mm->page_table_lock); -#endif - - __asm__ __volatile__( - "1: ldarx %0,0,%3\n\ - and. %1,%0,%6\n\ - bne- 1b \n\ - andc %1,%0,%4 \n\ - or %1,%1,%7\n\ - stdcx. %1,0,%3 \n\ - bne- 1b" - : "=&r" (old_be), "=&r" (tmp), "=m" (*pmdp) - : "r" (pmdp), "r" (cpu_to_be64(clr)), "m" (*pmdp), - "r" (cpu_to_be64(H_PAGE_BUSY)), "r" (cpu_to_be64(set)) - : "cc" ); - - old = be64_to_cpu(old_be); - - trace_hugepage_update(addr, old, clr, set); - if (old & H_PAGE_HASHPTE) - hpte_do_hugepage_flush(mm, addr, pmdp, old); - return old; -} - -pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address, - pmd_t *pmdp) -{ - pmd_t pmd; - - VM_BUG_ON(address & ~HPAGE_PMD_MASK); - VM_BUG_ON(pmd_trans_huge(*pmdp)); - - pmd = *pmdp; - pmd_clear(pmdp); - /* - * Wait for all pending hash_page to finish. This is needed - * in case of subpage collapse. When we collapse normal pages - * to hugepage, we first clear the pmd, then invalidate all - * the PTE entries. The assumption here is that any low level - * page fault will see a none pmd and take the slow path that - * will wait on mmap_sem. But we could very well be in a - * hash_page with local ptep pointer value. Such a hash page - * can result in adding new HPTE entries for normal subpages. - * That means we could be modifying the page content as we - * copy them to a huge page. So wait for parallel hash_page - * to finish before invalidating HPTE entries. We can do this - * by sending an IPI to all the cpus and executing a dummy - * function there. - */ - kick_all_cpus_sync(); - /* - * Now invalidate the hpte entries in the range - * covered by pmd. This make sure we take a - * fault and will find the pmd as none, which will - * result in a major fault which takes mmap_sem and - * hence wait for collapse to complete. Without this - * the __collapse_huge_page_copy can result in copying - * the old content. - */ - flush_tlb_pmd_range(vma->vm_mm, &pmd, address); - return pmd; -} - -/* - * We currently remove entries from the hashtable regardless of whether - * the entry was young or dirty. - * - * We should be more intelligent about this but for the moment we override - * these functions and force a tlb flush unconditionally - */ -int pmdp_test_and_clear_young(struct vm_area_struct *vma, - unsigned long address, pmd_t *pmdp) -{ - return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp); -} - -/* - * We want to put the pgtable in pmd and use pgtable for tracking - * the base page size hptes - */ -void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, - pgtable_t pgtable) -{ - pgtable_t *pgtable_slot; - assert_spin_locked(&mm->page_table_lock); - /* - * we store the pgtable in the second half of PMD - */ - pgtable_slot = (pgtable_t *)pmdp + PTRS_PER_PMD; - *pgtable_slot = pgtable; - /* - * expose the deposited pgtable to other cpus. - * before we set the hugepage PTE at pmd level - * hash fault code looks at the deposted pgtable - * to store hash index values. - */ - smp_wmb(); -} - -pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) -{ - pgtable_t pgtable; - pgtable_t *pgtable_slot; - - assert_spin_locked(&mm->page_table_lock); - pgtable_slot = (pgtable_t *)pmdp + PTRS_PER_PMD; - pgtable = *pgtable_slot; - /* - * Once we withdraw, mark the entry NULL. - */ - *pgtable_slot = NULL; - /* - * We store HPTE information in the deposited PTE fragment. - * zero out the content on withdraw. - */ - memset(pgtable, 0, PTE_FRAG_SIZE); - return pgtable; -} - -void pmdp_huge_split_prepare(struct vm_area_struct *vma, - unsigned long address, pmd_t *pmdp) -{ - VM_BUG_ON(address & ~HPAGE_PMD_MASK); - VM_BUG_ON(REGION_ID(address) != USER_REGION_ID); - - /* - * We can't mark the pmd none here, because that will cause a race - * against exit_mmap. We need to continue mark pmd TRANS HUGE, while - * we spilt, but at the same time we wan't rest of the ppc64 code - * not to insert hash pte on this, because we will be modifying - * the deposited pgtable in the caller of this function. Hence - * clear the _PAGE_USER so that we move the fault handling to - * higher level function and that will serialize against ptl. - * We need to flush existing hash pte entries here even though, - * the translation is still valid, because we will withdraw - * pgtable_t after this. - */ - pmd_hugepage_update(vma->vm_mm, address, pmdp, 0, _PAGE_PRIVILEGED); -} - - -/* - * set a new huge pmd. We should not be called for updating - * an existing pmd entry. That should go via pmd_hugepage_update. - */ -void set_pmd_at(struct mm_struct *mm, unsigned long addr, - pmd_t *pmdp, pmd_t pmd) -{ -#ifdef CONFIG_DEBUG_VM - 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 - trace_hugepage_set_pmd(addr, pmd_val(pmd)); - return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); -} - -/* - * We use this to invalidate a pmdp entry before switching from a - * hugepte to regular pmd entry. - */ -void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, - pmd_t *pmdp) -{ - pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, 0); - - /* - * This ensures that generic code that rely on IRQ disabling - * to prevent a parallel THP split work as expected. - */ - kick_all_cpus_sync(); -} - -/* - * A linux hugepage PMD was changed and the corresponding hash table entries - * neesd to be flushed. - */ -void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr, - pmd_t *pmdp, unsigned long old_pmd) -{ - int ssize; - unsigned int psize; - unsigned long vsid; - unsigned long flags = 0; - const struct cpumask *tmp; - - /* get the base page size,vsid and segment size */ -#ifdef CONFIG_DEBUG_VM - psize = get_slice_psize(mm, addr); - BUG_ON(psize == MMU_PAGE_16M); -#endif - if (old_pmd & H_PAGE_COMBO) - psize = MMU_PAGE_4K; - else - psize = MMU_PAGE_64K; - - if (!is_kernel_addr(addr)) { - ssize = user_segment_size(addr); - vsid = get_vsid(mm->context.id, addr, ssize); - WARN_ON(vsid == 0); - } else { - vsid = get_kernel_vsid(addr, mmu_kernel_ssize); - ssize = mmu_kernel_ssize; - } - - tmp = cpumask_of(smp_processor_id()); - if (cpumask_equal(mm_cpumask(mm), tmp)) - flags |= HPTE_LOCAL_UPDATE; - - return flush_hash_hugepage(vsid, addr, pmdp, psize, ssize, flags); -} - -static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot) -{ - return __pmd(pmd_val(pmd) | pgprot_val(pgprot)); -} - -pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot) -{ - unsigned long pmdv; - - pmdv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK; - return pmd_set_protbits(__pmd(pmdv), pgprot); -} - -pmd_t mk_pmd(struct page *page, pgprot_t pgprot) -{ - return pfn_pmd(page_to_pfn(page), pgprot); -} - -pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) -{ - unsigned long pmdv; - - pmdv = pmd_val(pmd); - pmdv &= _HPAGE_CHG_MASK; - return pmd_set_protbits(__pmd(pmdv), newprot); -} - -/* - * This is called at the end of handling a user page fault, when the - * fault has been handled by updating a HUGE PMD entry in the linux page tables. - * We use it to preload an HPTE into the hash table corresponding to - * the updated linux HUGE PMD entry. - */ -void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr, - pmd_t *pmd) -{ - return; -} - -pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, - unsigned long addr, pmd_t *pmdp) -{ - pmd_t old_pmd; - pgtable_t pgtable; - unsigned long old; - pgtable_t *pgtable_slot; - - old = pmd_hugepage_update(mm, addr, pmdp, ~0UL, 0); - old_pmd = __pmd(old); - /* - * We have pmd == none and we are holding page_table_lock. - * So we can safely go and clear the pgtable hash - * index info. - */ - pgtable_slot = (pgtable_t *)pmdp + PTRS_PER_PMD; - pgtable = *pgtable_slot; - /* - * Let's zero out old valid and hash index details - * hash fault look at them. - */ - memset(pgtable, 0, PTE_FRAG_SIZE); - /* - * Serialize against find_linux_pte_or_hugepte which does lock-less - * lookup in page tables with local interrupts disabled. For huge pages - * it casts pmd_t to pte_t. Since format of pte_t is different from - * pmd_t we want to prevent transit from pmd pointing to page table - * to pmd pointing to huge page (and back) while interrupts are disabled. - * We clear pmd to possibly replace it with page table pointer in - * different code paths. So make sure we wait for the parallel - * find_linux_pte_or_hugepage to finish. - */ - kick_all_cpus_sync(); - return old_pmd; -} - -int has_transparent_hugepage(void) -{ - - if (!mmu_has_feature(MMU_FTR_16M_PAGE)) - return 0; - /* - * We support THP only if PMD_SIZE is 16MB. - */ - if (mmu_psize_defs[MMU_PAGE_16M].shift != PMD_SHIFT) - return 0; - /* - * We need to make sure that we support 16MB hugepage in a segement - * with base page size 64K or 4K. We only enable THP with a PAGE_SIZE - * of 64K. - */ - /* - * If we have 64K HPTE, we will be using that by default - */ - if (mmu_psize_defs[MMU_PAGE_64K].shift && - (mmu_psize_defs[MMU_PAGE_64K].penc[MMU_PAGE_16M] == -1)) - return 0; - /* - * Ok we only have 4K HPTE - */ - if (mmu_psize_defs[MMU_PAGE_4K].penc[MMU_PAGE_16M] == -1) - return 0; - - return 1; -} -#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |