From patchwork Fri Jul 13 06:36:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Janosch Frank X-Patchwork-Id: 10522631 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 08607602B3 for ; Fri, 13 Jul 2018 06:37:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EADD2295CC for ; Fri, 13 Jul 2018 06:37:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DF305296CD; Fri, 13 Jul 2018 06:37:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 688F7295CC for ; Fri, 13 Jul 2018 06:37:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729775AbeGMGut (ORCPT ); Fri, 13 Jul 2018 02:50:49 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:52266 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729765AbeGMGut (ORCPT ); Fri, 13 Jul 2018 02:50:49 -0400 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w6D6XmLE040501 for ; Fri, 13 Jul 2018 02:37:38 -0400 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0a-001b2d01.pphosted.com with ESMTP id 2k6h4w2h8y-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 13 Jul 2018 02:37:38 -0400 Received: from localhost by e06smtp01.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 13 Jul 2018 07:37:32 +0100 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w6D6bWI142074274 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 13 Jul 2018 06:37:32 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 018CCA4040; Fri, 13 Jul 2018 09:37:53 +0100 (BST) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 647D5A4051; Fri, 13 Jul 2018 09:37:52 +0100 (BST) Received: from s38lp20.boeblingen.de.ibm.com (unknown [9.145.12.214]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 13 Jul 2018 09:37:52 +0100 (BST) From: Janosch Frank To: kvm@vger.kernel.org Cc: david@redhat.com, borntraeger@de.ibm.com, schwidefsky@de.ibm.com Subject: [PATCH v6 09/12] s390/mm: Add huge pmd storage key handling Date: Fri, 13 Jul 2018 07:36:59 +0100 X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180713063702.54628-1-frankja@linux.ibm.com> References: <20180713063702.54628-1-frankja@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18071306-4275-0000-0000-000002988802 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18071306-4276-0000-0000-000037A08E4B Message-Id: <20180713063702.54628-10-frankja@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-07-13_02:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1807130039 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Janosch Frank Storage keys for guests with huge page mappings have to be managed in hardware. There are no PGSTEs for PMDs that we could use to retain the guests's logical view of the key. Signed-off-by: Janosch Frank --- arch/s390/mm/pgtable.c | 87 +++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 76 insertions(+), 11 deletions(-) diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 6550ed56fcdf..161e08437681 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -782,12 +783,35 @@ EXPORT_SYMBOL_GPL(test_and_clear_guest_dirty); int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, unsigned char key, bool nq) { - unsigned long keyul; + unsigned long keyul, paddr; spinlock_t *ptl; pgste_t old, new; + pmd_t *pmdp; pte_t *ptep; - ptep = get_locked_pte(mm, addr, &ptl); + pmdp = (pmd_t *)huge_pte_offset(mm, addr, HPAGE_SIZE); + if (!pmdp) + return -EFAULT; + + ptl = pmd_lock(mm, pmdp); + if (!pmd_present(*pmdp)) { + spin_unlock(ptl); + return -EFAULT; + } + if (pmd_large(*pmdp)) { + paddr = pmd_val(*pmdp) & HPAGE_MASK; + paddr |= addr & ~HPAGE_MASK; + /* + * Huge pmds need quiescing operations, they are + * always mapped. + */ + page_set_storage_key(paddr, key, 1); + spin_unlock(ptl); + return 0; + } + spin_unlock(ptl); + + ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl); if (unlikely(!ptep)) return -EFAULT; @@ -798,14 +822,14 @@ int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, pgste_val(new) |= (keyul & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48; pgste_val(new) |= (keyul & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56; if (!(pte_val(*ptep) & _PAGE_INVALID)) { - unsigned long address, bits, skey; + unsigned long bits, skey; - address = pte_val(*ptep) & PAGE_MASK; - skey = (unsigned long) page_get_storage_key(address); + paddr = pte_val(*ptep) & PAGE_MASK; + skey = (unsigned long) page_get_storage_key(paddr); bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED); skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT); /* Set storage key ACC and FP */ - page_set_storage_key(address, skey, !nq); + page_set_storage_key(paddr, skey, !nq); /* Merge host changed & referenced into pgste */ pgste_val(new) |= bits << 52; } @@ -861,20 +885,40 @@ EXPORT_SYMBOL(cond_set_guest_storage_key); int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr) { spinlock_t *ptl; + unsigned long paddr; pgste_t old, new; + pmd_t *pmdp; pte_t *ptep; int cc = 0; - ptep = get_locked_pte(mm, addr, &ptl); - if (unlikely(!ptep)) + pmdp = (pmd_t *)huge_pte_offset(mm, addr, HPAGE_SIZE); + if (!pmdp) return -EFAULT; + ptl = pmd_lock(mm, pmdp); + if (!pmd_present(*pmdp)) { + spin_unlock(ptl); + return -EFAULT; + } + if (pmd_large(*pmdp)) { + paddr = pmd_val(*pmdp) & HPAGE_MASK; + paddr |= addr & ~HPAGE_MASK; + cc = page_reset_referenced(paddr); + spin_unlock(ptl); + return cc; + } + spin_unlock(ptl); + + ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl); + if (unlikely(!ptep)) + return -EFAULT; new = old = pgste_get_lock(ptep); /* Reset guest reference bit only */ pgste_val(new) &= ~PGSTE_GR_BIT; if (!(pte_val(*ptep) & _PAGE_INVALID)) { - cc = page_reset_referenced(pte_val(*ptep) & PAGE_MASK); + paddr = pte_val(*ptep) & PAGE_MASK; + cc = page_reset_referenced(paddr); /* Merge real referenced bit into host-set */ pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT; } @@ -893,18 +937,39 @@ EXPORT_SYMBOL(reset_guest_reference_bit); int get_guest_storage_key(struct mm_struct *mm, unsigned long addr, unsigned char *key) { + unsigned long paddr; spinlock_t *ptl; pgste_t pgste; + pmd_t *pmdp; pte_t *ptep; - ptep = get_locked_pte(mm, addr, &ptl); + pmdp = (pmd_t *)huge_pte_offset(mm, addr, HPAGE_SIZE); + if (!pmdp) + return -EFAULT; + + ptl = pmd_lock(mm, pmdp); + if (!pmd_present(*pmdp)) { + spin_unlock(ptl); + return -EFAULT; + } + if (pmd_large(*pmdp)) { + paddr = pmd_val(*pmdp) & HPAGE_MASK; + paddr |= addr & ~HPAGE_MASK; + *key = page_get_storage_key(paddr); + spin_unlock(ptl); + return 0; + } + spin_unlock(ptl); + + ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl); if (unlikely(!ptep)) return -EFAULT; pgste = pgste_get_lock(ptep); *key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56; + paddr = pte_val(*ptep) & PAGE_MASK; if (!(pte_val(*ptep) & _PAGE_INVALID)) - *key = page_get_storage_key(pte_val(*ptep) & PAGE_MASK); + *key = page_get_storage_key(paddr); /* Reflect guest's logical view, not physical */ *key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48; pgste_set_unlock(ptep, pgste);