// SPDX-License-Identifier: GPL-2.0-or-later /* * This file contains the routines for TLB flushing. * On machines where the MMU does not use a hash table to store virtual to * physical translations (ie, SW loaded TLBs or Book3E compilant processors, * this does -not- include 603 however which shares the implementation with * hash based processors) * * -- BenH * * Copyright 2008,2009 Ben Herrenschmidt * IBM Corp. * * Derived from arch/ppc/mm/init.c: * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) * and Cort Dougan (PReP) (cort@cs.nmt.edu) * Copyright (C) 1996 Paul Mackerras * * Derived from "arch/i386/mm/init.c" * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * This struct lists the sw-supported page sizes. The hardawre MMU may support * other sizes not listed here. The .ind field is only used on MMUs that have * indirect page table entries. */ #ifdef CONFIG_PPC_E500 struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = { [MMU_PAGE_4K] = { .shift = 12, }, [MMU_PAGE_2M] = { .shift = 21, }, [MMU_PAGE_4M] = { .shift = 22, }, [MMU_PAGE_16M] = { .shift = 24, }, [MMU_PAGE_64M] = { .shift = 26, }, [MMU_PAGE_256M] = { .shift = 28, }, [MMU_PAGE_1G] = { .shift = 30, }, }; static inline int mmu_get_tsize(int psize) { return mmu_psize_defs[psize].shift - 10; } #else static inline int mmu_get_tsize(int psize) { /* This isn't used on !Book3E for now */ return 0; } #endif #ifdef CONFIG_PPC_8xx struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = { [MMU_PAGE_4K] = { .shift = 12, }, [MMU_PAGE_16K] = { .shift = 14, }, [MMU_PAGE_512K] = { .shift = 19, }, [MMU_PAGE_8M] = { .shift = 23, }, }; #endif #ifdef CONFIG_PPC_E500 /* next_tlbcam_idx is used to round-robin tlbcam entry assignment */ DEFINE_PER_CPU(int, next_tlbcam_idx); EXPORT_PER_CPU_SYMBOL(next_tlbcam_idx); #endif /* * Base TLB flushing operations: * * - flush_tlb_mm(mm) flushes the specified mm context TLB's * - flush_tlb_page(vma, vmaddr) flushes one page * - flush_tlb_range(vma, start, end) flushes a range of pages * - flush_tlb_kernel_range(start, end) flushes kernel pages * * - local_* variants of page and mm only apply to the current * processor */ #ifndef CONFIG_PPC_8xx /* * These are the base non-SMP variants of page and mm flushing */ void local_flush_tlb_mm(struct mm_struct *mm) { unsigned int pid; preempt_disable(); pid = mm->context.id; if (pid != MMU_NO_CONTEXT) _tlbil_pid(pid); preempt_enable(); } EXPORT_SYMBOL(local_flush_tlb_mm); void __local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr, int tsize, int ind) { unsigned int pid; preempt_disable(); pid = mm ? mm->context.id : 0; if (pid != MMU_NO_CONTEXT) _tlbil_va(vmaddr, pid, tsize, ind); preempt_enable(); } void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) { __local_flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr, mmu_get_tsize(mmu_virtual_psize), 0); } EXPORT_SYMBOL(local_flush_tlb_page); void local_flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmaddr, int psize) { __local_flush_tlb_page(mm, vmaddr, mmu_get_tsize(psize), 0); } EXPORT_SYMBOL(local_flush_tlb_page_psize); #endif /* * And here are the SMP non-local implementations */ #ifdef CONFIG_SMP static DEFINE_RAW_SPINLOCK(tlbivax_lock); struct tlb_flush_param { unsigned long addr; unsigned int pid; unsigned int tsize; unsigned int ind; }; static void do_flush_tlb_mm_ipi(void *param) { struct tlb_flush_param *p = param; _tlbil_pid(p ? p->pid : 0); } static void do_flush_tlb_page_ipi(void *param) { struct tlb_flush_param *p = param; _tlbil_va(p->addr, p->pid, p->tsize, p->ind); } /* Note on invalidations and PID: * * We snapshot the PID with preempt disabled. At this point, it can still * change either because: * - our context is being stolen (PID -> NO_CONTEXT) on another CPU * - we are invaliating some target that isn't currently running here * and is concurrently acquiring a new PID on another CPU * - some other CPU is re-acquiring a lost PID for this mm * etc... * * However, this shouldn't be a problem as we only guarantee * invalidation of TLB entries present prior to this call, so we * don't care about the PID changing, and invalidating a stale PID * is generally harmless. */ void flush_tlb_mm(struct mm_struct *mm) { unsigned int pid; preempt_disable(); pid = mm->context.id; if (unlikely(pid == MMU_NO_CONTEXT)) goto no_context; if (!mm_is_core_local(mm)) { struct tlb_flush_param p = { .pid = pid }; /* Ignores smp_processor_id() even if set. */ smp_call_function_many(mm_cpumask(mm), do_flush_tlb_mm_ipi, &p, 1); } _tlbil_pid(pid); no_context: preempt_enable(); } EXPORT_SYMBOL(flush_tlb_mm); void __flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr, int tsize, int ind) { struct cpumask *cpu_mask; unsigned int pid; /* * This function as well as __local_flush_tlb_page() must only be called * for user contexts. */ if (WARN_ON(!mm)) return; preempt_disable(); pid = mm->context.id; if (unlikely(pid == MMU_NO_CONTEXT)) goto bail; cpu_mask = mm_cpumask(mm); if (!mm_is_core_local(mm)) { /* If broadcast tlbivax is supported, use it */ if (mmu_has_feature(MMU_FTR_USE_TLBIVAX_BCAST)) { int lock = mmu_has_feature(MMU_FTR_LOCK_BCAST_INVAL); if (lock) raw_spin_lock(&tlbivax_lock); _tlbivax_bcast(vmaddr, pid, tsize, ind); if (lock) raw_spin_unlock(&tlbivax_lock); goto bail; } else { struct tlb_flush_param p = { .pid = pid, .addr = vmaddr, .tsize = tsize, .ind = ind, }; /* Ignores smp_processor_id() even if set in cpu_mask */ smp_call_function_many(cpu_mask, do_flush_tlb_page_ipi, &p, 1); } } _tlbil_va(vmaddr, pid, tsize, ind); bail: preempt_enable(); } void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) { #ifdef CONFIG_HUGETLB_PAGE if (vma && is_vm_hugetlb_page(vma)) flush_hugetlb_page(vma, vmaddr); #endif __flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr, mmu_get_tsize(mmu_virtual_psize), 0); } EXPORT_SYMBOL(flush_tlb_page); #endif /* CONFIG_SMP */ /* * Flush kernel TLB entries in the given range */ #ifndef CONFIG_PPC_8xx void flush_tlb_kernel_range(unsigned long start, unsigned long end) { #ifdef CONFIG_SMP preempt_disable(); smp_call_function(do_flush_tlb_mm_ipi, NULL, 1); _tlbil_pid(0); preempt_enable(); #else _tlbil_pid(0); #endif } EXPORT_SYMBOL(flush_tlb_kernel_range); #endif /* * Currently, for range flushing, we just do a full mm flush. This should * be optimized based on a threshold on the size of the range, since * some implementation can stack multiple tlbivax before a tlbsync but * for now, we keep it that way */ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { if (end - start == PAGE_SIZE && !(start & ~PAGE_MASK)) flush_tlb_page(vma, start); else flush_tlb_mm(vma->vm_mm); } EXPORT_SYMBOL(flush_tlb_range); void tlb_flush(struct mmu_gather *tlb) { flush_tlb_mm(tlb->mm); } #ifndef CONFIG_PPC64 void __init early_init_mmu(void) { unsigned long root = of_get_flat_dt_root(); if (IS_ENABLED(CONFIG_PPC_47x) && IS_ENABLED(CONFIG_SMP) && of_get_flat_dt_prop(root, "cooperative-partition", NULL)) mmu_clear_feature(MMU_FTR_USE_TLBIVAX_BCAST); } #endif /* CONFIG_PPC64 */