From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CE74C433E2 for ; Wed, 22 Jul 2020 09:46:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 20ED820787 for ; Wed, 22 Jul 2020 09:46:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UAA5+0JE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731799AbgGVJqX (ORCPT ); Wed, 22 Jul 2020 05:46:23 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:27141 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728599AbgGVJqU (ORCPT ); Wed, 22 Jul 2020 05:46:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595411177; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=S/ZCJ73tThfgdUm39GPYl5/cniEHqvV3g51y8B+8z7M=; b=UAA5+0JEpJIhDMbaACHkxxcg9SMDOyzhJYNTDvZ0f9wHwUTQEvQgmRYAvSwZp37t/0llJi +5V9DJptxpjn1SIBdMx9gE42Iq98S+9WKiqGcL5ghP5lzm6eTTGF4+AwgUYa2ScfpcKlUU r7EvN97yH20LZ0bnpE/bgVlVniGKAWo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-97-y91DIA_9N5yAnnERJ6uj7Q-1; Wed, 22 Jul 2020 05:46:11 -0400 X-MC-Unique: y91DIA_9N5yAnnERJ6uj7Q-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 606C0100CCC3; Wed, 22 Jul 2020 09:46:10 +0000 (UTC) Received: from t480s.redhat.com (ovpn-113-254.ams2.redhat.com [10.36.113.254]) by smtp.corp.redhat.com (Postfix) with ESMTP id B0D045D9CA; Wed, 22 Jul 2020 09:46:08 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-s390@vger.kernel.org, linux-mm@kvack.org, David Hildenbrand , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Gerald Schaefer Subject: [PATCH v2 2/9] s390/vmem: consolidate vmem_add_range() and vmem_remove_range() Date: Wed, 22 Jul 2020 11:45:51 +0200 Message-Id: <20200722094558.9828-3-david@redhat.com> In-Reply-To: <20200722094558.9828-1-david@redhat.com> References: <20200722094558.9828-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We want to have only a single pagetable walker and reuse the same functionality for vmemmap handling. Let's start by consolidating vmem_add_range() and vmem_remove_range(), converting it into a recursive implementation. A recursive implementation makes it easier to expand individual cases without harming readability. In addition, we minimize traversing the whole hierarchy over and over again. One change is that we don't unmap large PMDs/PUDs when not completely covered by the request, something that should never happen with direct mappings, unless one would be removing in other granularity than added, which would be broken already. Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: Gerald Schaefer Signed-off-by: David Hildenbrand --- arch/s390/mm/vmem.c | 317 +++++++++++++++++++++++++++----------------- 1 file changed, 198 insertions(+), 119 deletions(-) diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c index 66c5333020ead..177daf389d391 100644 --- a/arch/s390/mm/vmem.c +++ b/arch/s390/mm/vmem.c @@ -54,148 +54,227 @@ pte_t __ref *vmem_pte_alloc(void) return pte; } -/* - * Add a physical memory range to the 1:1 mapping. - */ -static int vmem_add_range(unsigned long start, unsigned long size) +static void modify_pte_table(pmd_t *pmd, unsigned long addr, unsigned long end, + bool add) { - unsigned long pgt_prot, sgt_prot, r3_prot; - unsigned long pages4k, pages1m, pages2g; - unsigned long end = start + size; - unsigned long address = start; - pgd_t *pg_dir; - p4d_t *p4_dir; - pud_t *pu_dir; - pmd_t *pm_dir; - pte_t *pt_dir; - int ret = -ENOMEM; + unsigned long prot, pages = 0; + pte_t *pte; - pgt_prot = pgprot_val(PAGE_KERNEL); - sgt_prot = pgprot_val(SEGMENT_KERNEL); - r3_prot = pgprot_val(REGION3_KERNEL); - if (!MACHINE_HAS_NX) { - pgt_prot &= ~_PAGE_NOEXEC; - sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC; - r3_prot &= ~_REGION_ENTRY_NOEXEC; + prot = pgprot_val(PAGE_KERNEL); + if (!MACHINE_HAS_NX) + prot &= ~_PAGE_NOEXEC; + + pte = pte_offset_kernel(pmd, addr); + for (; addr < end; addr += PAGE_SIZE, pte++) { + if (!add) { + if (pte_none(*pte)) + continue; + pte_clear(&init_mm, addr, pte); + } else if (pte_none(*pte)) { + pte_val(*pte) = addr | prot; + } else + continue; + + pages++; } - pages4k = pages1m = pages2g = 0; - while (address < end) { - pg_dir = pgd_offset_k(address); - if (pgd_none(*pg_dir)) { - p4_dir = vmem_crst_alloc(_REGION2_ENTRY_EMPTY); - if (!p4_dir) - goto out; - pgd_populate(&init_mm, pg_dir, p4_dir); - } - p4_dir = p4d_offset(pg_dir, address); - if (p4d_none(*p4_dir)) { - pu_dir = vmem_crst_alloc(_REGION3_ENTRY_EMPTY); - if (!pu_dir) + + update_page_count(PG_DIRECT_MAP_4K, add ? pages : -pages); +} + +static int modify_pmd_table(pud_t *pud, unsigned long addr, unsigned long end, + bool add) +{ + unsigned long next, prot, pages = 0; + int ret = -ENOMEM; + pmd_t *pmd; + pte_t *pte; + + prot = pgprot_val(SEGMENT_KERNEL); + if (!MACHINE_HAS_NX) + prot &= ~_SEGMENT_ENTRY_NOEXEC; + + pmd = pmd_offset(pud, addr); + for (; addr < end; addr = next, pmd++) { + next = pmd_addr_end(addr, end); + + if (!add) { + if (pmd_none(*pmd)) + continue; + if (pmd_large(*pmd) && !add) { + if (IS_ALIGNED(addr, PMD_SIZE) && + IS_ALIGNED(next, PMD_SIZE)) { + pmd_clear(pmd); + pages++; + } + continue; + } + } else if (pmd_none(*pmd)) { + if (IS_ALIGNED(addr, PMD_SIZE) && + IS_ALIGNED(next, PMD_SIZE) && + MACHINE_HAS_EDAT1 && addr && + !debug_pagealloc_enabled()) { + pmd_val(*pmd) = addr | prot; + pages++; + continue; + } + pte = vmem_pte_alloc(); + if (!pte) goto out; - p4d_populate(&init_mm, p4_dir, pu_dir); - } - pu_dir = pud_offset(p4_dir, address); - if (MACHINE_HAS_EDAT2 && pud_none(*pu_dir) && address && - !(address & ~PUD_MASK) && (address + PUD_SIZE <= end) && - !debug_pagealloc_enabled()) { - pud_val(*pu_dir) = address | r3_prot; - address += PUD_SIZE; - pages2g++; + pmd_populate(&init_mm, pmd, pte); + } else if (pmd_large(*pmd)) continue; - } - if (pud_none(*pu_dir)) { - pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY); - if (!pm_dir) + + modify_pte_table(pmd, addr, next, add); + } + ret = 0; +out: + update_page_count(PG_DIRECT_MAP_1M, add ? pages : -pages); + return ret; +} + +static int modify_pud_table(p4d_t *p4d, unsigned long addr, unsigned long end, + bool add) +{ + unsigned long next, prot, pages = 0; + int ret = -ENOMEM; + pud_t *pud; + pmd_t *pmd; + + prot = pgprot_val(REGION3_KERNEL); + if (!MACHINE_HAS_NX) + prot &= ~_REGION_ENTRY_NOEXEC; + + pud = pud_offset(p4d, addr); + for (; addr < end; addr = next, pud++) { + next = pud_addr_end(addr, end); + + if (!add) { + if (pud_none(*pud)) + continue; + if (pud_large(*pud)) { + if (IS_ALIGNED(addr, PUD_SIZE) && + IS_ALIGNED(next, PUD_SIZE)) { + pud_clear(pud); + pages++; + } + continue; + } + } else if (pud_none(*pud)) { + if (IS_ALIGNED(addr, PUD_SIZE) && + IS_ALIGNED(next, PUD_SIZE) && + MACHINE_HAS_EDAT2 && addr && + !debug_pagealloc_enabled()) { + pud_val(*pud) = addr | prot; + pages++; + continue; + } + pmd = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY); + if (!pmd) goto out; - pud_populate(&init_mm, pu_dir, pm_dir); - } - pm_dir = pmd_offset(pu_dir, address); - if (MACHINE_HAS_EDAT1 && pmd_none(*pm_dir) && address && - !(address & ~PMD_MASK) && (address + PMD_SIZE <= end) && - !debug_pagealloc_enabled()) { - pmd_val(*pm_dir) = address | sgt_prot; - address += PMD_SIZE; - pages1m++; + pud_populate(&init_mm, pud, pmd); + } else if (pud_large(*pud)) continue; + + ret = modify_pmd_table(pud, addr, next, add); + if (ret) + goto out; + } + ret = 0; +out: + update_page_count(PG_DIRECT_MAP_2G, add ? pages : -pages); + return ret; +} + +static int modify_p4d_table(pgd_t *pgd, unsigned long addr, unsigned long end, + bool add) +{ + unsigned long next; + int ret = -ENOMEM; + p4d_t *p4d; + pud_t *pud; + + p4d = p4d_offset(pgd, addr); + for (; addr < end; addr = next, p4d++) { + next = p4d_addr_end(addr, end); + + if (!add) { + if (p4d_none(*p4d)) + continue; + } else if (p4d_none(*p4d)) { + pud = vmem_crst_alloc(_REGION3_ENTRY_EMPTY); + if (!pud) + goto out; } - if (pmd_none(*pm_dir)) { - pt_dir = vmem_pte_alloc(); - if (!pt_dir) + + ret = modify_pud_table(p4d, addr, next, add); + if (ret) + goto out; + } + ret = 0; +out: + return ret; +} + +static int modify_pagetable(unsigned long start, unsigned long end, bool add) +{ + unsigned long addr, next; + int ret = -ENOMEM; + pgd_t *pgd; + p4d_t *p4d; + + if (WARN_ON_ONCE(!PAGE_ALIGNED(start | end))) + return -EINVAL; + + for (addr = start; addr < end; addr = next) { + next = pgd_addr_end(addr, end); + pgd = pgd_offset_k(addr); + + if (!add) { + if (pgd_none(*pgd)) + continue; + } else if (pgd_none(*pgd)) { + p4d = vmem_crst_alloc(_REGION2_ENTRY_EMPTY); + if (!p4d) goto out; - pmd_populate(&init_mm, pm_dir, pt_dir); + pgd_populate(&init_mm, pgd, p4d); } - pt_dir = pte_offset_kernel(pm_dir, address); - pte_val(*pt_dir) = address | pgt_prot; - address += PAGE_SIZE; - pages4k++; + ret = modify_p4d_table(pgd, addr, next, add); + if (ret) + goto out; } ret = 0; out: - update_page_count(PG_DIRECT_MAP_4K, pages4k); - update_page_count(PG_DIRECT_MAP_1M, pages1m); - update_page_count(PG_DIRECT_MAP_2G, pages2g); + if (!add) + flush_tlb_kernel_range(start, end); return ret; } +static int add_pagetable(unsigned long start, unsigned long end) +{ + return modify_pagetable(start, end, true); +} + +static int remove_pagetable(unsigned long start, unsigned long end) +{ + return modify_pagetable(start, end, false); +} + +/* + * Add a physical memory range to the 1:1 mapping. + */ +static int vmem_add_range(unsigned long start, unsigned long size) +{ + return add_pagetable(start, start + size); +} + /* * Remove a physical memory range from the 1:1 mapping. * Currently only invalidates page table entries. */ static void vmem_remove_range(unsigned long start, unsigned long size) { - unsigned long pages4k, pages1m, pages2g; - unsigned long end = start + size; - unsigned long address = start; - pgd_t *pg_dir; - p4d_t *p4_dir; - pud_t *pu_dir; - pmd_t *pm_dir; - pte_t *pt_dir; - - pages4k = pages1m = pages2g = 0; - while (address < end) { - pg_dir = pgd_offset_k(address); - if (pgd_none(*pg_dir)) { - address += PGDIR_SIZE; - continue; - } - p4_dir = p4d_offset(pg_dir, address); - if (p4d_none(*p4_dir)) { - address += P4D_SIZE; - continue; - } - pu_dir = pud_offset(p4_dir, address); - if (pud_none(*pu_dir)) { - address += PUD_SIZE; - continue; - } - if (pud_large(*pu_dir)) { - pud_clear(pu_dir); - address += PUD_SIZE; - pages2g++; - continue; - } - pm_dir = pmd_offset(pu_dir, address); - if (pmd_none(*pm_dir)) { - address += PMD_SIZE; - continue; - } - if (pmd_large(*pm_dir)) { - pmd_clear(pm_dir); - address += PMD_SIZE; - pages1m++; - continue; - } - pt_dir = pte_offset_kernel(pm_dir, address); - pte_clear(&init_mm, address, pt_dir); - address += PAGE_SIZE; - pages4k++; - } - flush_tlb_kernel_range(start, end); - update_page_count(PG_DIRECT_MAP_4K, -pages4k); - update_page_count(PG_DIRECT_MAP_1M, -pages1m); - update_page_count(PG_DIRECT_MAP_2G, -pages2g); + remove_pagetable(start, start + size); } /* -- 2.26.2