diff options
Diffstat (limited to 'arch/powerpc/mm/book3s64/hash_utils.c')
| -rw-r--r-- | arch/powerpc/mm/book3s64/hash_utils.c | 72 |
1 files changed, 21 insertions, 51 deletions
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index 8ed2411c3f39..0124003e60d0 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -66,6 +66,9 @@ #include <mm/mmu_decl.h> +#include "internal.h" + + #ifdef DEBUG #define DBG(fmt...) udbg_printf(fmt) #else @@ -870,6 +873,9 @@ static void __init htab_initialize(void) printk(KERN_INFO "Using 1TB segments\n"); } + if (stress_slb_enabled) + static_branch_enable(&stress_slb_key); + /* * Calculate the required size of the htab. We want the number of * PTEGs to equal one half the number of real pages. @@ -1350,8 +1356,15 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea, goto bail; } - /* Add _PAGE_PRESENT to the required access perm */ - access |= _PAGE_PRESENT; + /* + * Add _PAGE_PRESENT to the required access perm. If there are parallel + * updates to the pte that can possibly clear _PAGE_PTE, catch that too. + * + * We can safely use the return pte address in rest of the function + * because we do set H_PAGE_BUSY which prevents further updates to pte + * from generic code. + */ + access |= _PAGE_PRESENT | _PAGE_PTE; /* * Pre-check access permissions (will be re-checked atomically @@ -1539,14 +1552,11 @@ static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) } #endif -static void hash_preload(struct mm_struct *mm, unsigned long ea, +static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea, bool is_exec, unsigned long trap) { - int hugepage_shift; unsigned long vsid; pgd_t *pgdir; - pte_t *ptep; - unsigned long flags; int rc, ssize, update_flags = 0; unsigned long access = _PAGE_PRESENT | _PAGE_READ | (is_exec ? _PAGE_EXEC : 0); @@ -1568,30 +1578,18 @@ static void hash_preload(struct mm_struct *mm, unsigned long ea, vsid = get_user_vsid(&mm->context, ea, ssize); if (!vsid) return; - /* - * Hash doesn't like irqs. Walking linux page table with irq disabled - * saves us from holding multiple locks. - */ - local_irq_save(flags); - /* - * THP pages use update_mmu_cache_pmd. We don't do - * hash preload there. Hence can ignore THP here - */ - ptep = find_current_mm_pte(pgdir, ea, NULL, &hugepage_shift); - if (!ptep) - goto out_exit; - - WARN_ON(hugepage_shift); #ifdef CONFIG_PPC_64K_PAGES /* If either H_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 + * Called with PTL held, hence can be sure the value won't change in + * between. */ if ((pte_val(*ptep) & H_PAGE_4K_PFN) || pte_ci(*ptep)) - goto out_exit; + return; #endif /* CONFIG_PPC_64K_PAGES */ /* Is that local to this CPU ? */ @@ -1616,8 +1614,6 @@ static void hash_preload(struct mm_struct *mm, unsigned long ea, mm_ctx_user_psize(&mm->context), mm_ctx_user_psize(&mm->context), pte_val(*ptep)); -out_exit: - local_irq_restore(flags); } /* @@ -1638,10 +1634,8 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, unsigned long trap; bool is_exec; - if (radix_enabled()) { - prefetch((void *)address); + if (radix_enabled()) return; - } /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ if (!pte_young(*ptep) || address >= TASK_SIZE) @@ -1668,32 +1662,8 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, return; } - hash_preload(vma->vm_mm, address, is_exec, trap); -} - -#ifdef CONFIG_PPC_MEM_KEYS -/* - * Return the protection key associated with the given address and the - * mm_struct. - */ -u16 get_mm_addr_key(struct mm_struct *mm, unsigned long address) -{ - pte_t *ptep; - u16 pkey = 0; - unsigned long flags; - - if (!mm || !mm->pgd) - return 0; - - local_irq_save(flags); - ptep = find_linux_pte(mm->pgd, address, NULL, NULL); - if (ptep) - pkey = pte_to_pkey_bits(pte_val(READ_ONCE(*ptep))); - local_irq_restore(flags); - - return pkey; + hash_preload(vma->vm_mm, ptep, address, is_exec, trap); } -#endif /* CONFIG_PPC_MEM_KEYS */ #ifdef CONFIG_PPC_TRANSACTIONAL_MEM static inline void tm_flush_hash_page(int local) |