diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c index 3557d78ee47a..5a87c12f444a 100644 --- a/drivers/misc/sgi-gru/grufault.c +++ b/drivers/misc/sgi-gru/grufault.c @@ -166,13 +166,8 @@ static void get_clear_fault_map(struct gru_state *gru, } /* - * Atomic (interrupt context) & non-atomic (user context) functions to - * convert a vaddr into a physical address. The size of the page - * is returned in pageshift. - * returns: - * 0 - successful - * < 0 - error code - * 1 - (atomic only) try again in non-atomic context + * Convert a user virtual address to a physical address in process context. + * The size of the page is returned in pageshift. */ static int non_atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, int write, @@ -192,87 +187,25 @@ static int non_atomic_pte_lookup(struct vm_area_struct *vma, return 0; } -/* - * atomic_pte_lookup - * - * Convert a user virtual address to a physical address - * Only supports Intel large pages (2MB only) on x86_64. - * ZZZ - hugepage support is incomplete - * - * NOTE: mmap_lock is already held on entry to this function. This - * guarantees existence of the page tables. - */ -static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr, - int write, unsigned long *paddr, int *pageshift) -{ - pgd_t *pgdp; - p4d_t *p4dp; - pud_t *pudp; - pmd_t *pmdp; - pte_t pte; - - pgdp = pgd_offset(vma->vm_mm, vaddr); - if (unlikely(pgd_none(*pgdp))) - goto err; - - p4dp = p4d_offset(pgdp, vaddr); - if (unlikely(p4d_none(*p4dp))) - goto err; - - pudp = pud_offset(p4dp, vaddr); - if (unlikely(pud_none(*pudp))) - goto err; - - pmdp = pmd_offset(pudp, vaddr); - if (unlikely(pmd_none(*pmdp))) - goto err; -#ifdef CONFIG_X86_64 - if (unlikely(pmd_leaf(*pmdp))) - pte = ptep_get((pte_t *)pmdp); - else -#endif - pte = *pte_offset_kernel(pmdp, vaddr); - - if (unlikely(!pte_present(pte) || - (write && (!pte_write(pte) || !pte_dirty(pte))))) - return 1; - - *paddr = pte_pfn(pte) << PAGE_SHIFT; -#ifdef CONFIG_HUGETLB_PAGE - *pageshift = is_vm_hugetlb_page(vma) ? HPAGE_SHIFT : PAGE_SHIFT; -#else - *pageshift = PAGE_SHIFT; -#endif - return 0; - -err: - return 1; -} - static int gru_vtop(struct gru_thread_state *gts, unsigned long vaddr, int write, int atomic, unsigned long *gpa, int *pageshift) { struct mm_struct *mm = gts->ts_mm; struct vm_area_struct *vma; unsigned long paddr; - int ret, ps; + int ps; vma = find_vma(mm, vaddr); if (!vma) goto inval; - /* - * Atomic lookup is faster & usually works even if called in non-atomic - * context. - */ - rmb(); /* Must/check ms_range_active before loading PTEs */ - ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &ps); - if (ret) { - if (atomic) - goto upm; - if (non_atomic_pte_lookup(vma, vaddr, write, &paddr, &ps)) - goto inval; - } + if (atomic) + goto upm; + + /* Order the caller's ms_range_active check before loading PTEs. */ + rmb(); + if (non_atomic_pte_lookup(vma, vaddr, write, &paddr, &ps)) + goto inval; if (is_gru_paddr(paddr)) goto inval; paddr = paddr & ~((1UL << ps) - 1); @@ -569,19 +502,9 @@ static irqreturn_t gru_intr(int chiplet, int blade) continue; } - /* - * This is running in interrupt context. Trylock the mmap_lock. - * If it fails, retry the fault in user context. - */ + /* Address translation may sleep, so retry the fault in user context. */ gts->ustats.fmm_tlbmiss++; - if (!gts->ts_force_cch_reload && - mmap_read_trylock(gts->ts_mm)) { - gru_try_dropin(gru, gts, tfh, NULL); - mmap_read_unlock(gts->ts_mm); - } else { - tfh_user_polling_mode(tfh); - STAT(intr_mm_lock_failed); - } + tfh_user_polling_mode(tfh); } return IRQ_HANDLED; } diff --git a/drivers/misc/sgi-gru/gruprocfs.c b/drivers/misc/sgi-gru/gruprocfs.c index 97b8b38ab47d..b8139c27bc7f 100644 --- a/drivers/misc/sgi-gru/gruprocfs.c +++ b/drivers/misc/sgi-gru/gruprocfs.c @@ -54,7 +54,6 @@ static int statistics_show(struct seq_file *s, void *p) printstat(s, intr_cbr); printstat(s, intr_tfh); printstat(s, intr_spurious); - printstat(s, intr_mm_lock_failed); printstat(s, call_os); printstat(s, call_os_wait_queue); printstat(s, user_flush_tlb); diff --git a/drivers/misc/sgi-gru/grutables.h b/drivers/misc/sgi-gru/grutables.h index 640daf1994df..3348552925c6 100644 --- a/drivers/misc/sgi-gru/grutables.h +++ b/drivers/misc/sgi-gru/grutables.h @@ -182,7 +182,6 @@ struct gru_stats_s { atomic_long_t intr_cbr; atomic_long_t intr_tfh; atomic_long_t intr_spurious; - atomic_long_t intr_mm_lock_failed; atomic_long_t call_os; atomic_long_t call_os_wait_queue; atomic_long_t user_flush_tlb;