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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=no 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 55679C43603 for ; Mon, 9 Dec 2019 03:20:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2898C206E0 for ; Mon, 9 Dec 2019 03:20:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727054AbfLIDU6 (ORCPT ); Sun, 8 Dec 2019 22:20:58 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:53816 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726834AbfLIDU6 (ORCPT ); Sun, 8 Dec 2019 22:20:58 -0500 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xB93COJ3026553; Sun, 8 Dec 2019 22:20:25 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2wrte588jg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 08 Dec 2019 22:20:25 -0500 Received: from m0098393.ppops.net (m0098393.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id xB93CwxW027647; Sun, 8 Dec 2019 22:20:24 -0500 Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0a-001b2d01.pphosted.com with ESMTP id 2wrte588ja-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 08 Dec 2019 22:20:24 -0500 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id xB93GLVZ009672; Mon, 9 Dec 2019 03:20:23 GMT Received: from b03cxnp08028.gho.boulder.ibm.com (b03cxnp08028.gho.boulder.ibm.com [9.17.130.20]) by ppma04dal.us.ibm.com with ESMTP id 2wr3q631jw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 09 Dec 2019 03:20:23 +0000 Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xB93KMKF66584954 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 9 Dec 2019 03:20:22 GMT Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 29BE46A051; Mon, 9 Dec 2019 03:20:22 +0000 (GMT) Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 900B36A04D; Mon, 9 Dec 2019 03:20:21 +0000 (GMT) Received: from [9.70.82.143] (unknown [9.70.82.143]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP; Mon, 9 Dec 2019 03:20:21 +0000 (GMT) Subject: [PATCH V2 00/13] powerpc/vas: Page fault handling for user space NX requests From: Haren Myneni To: mpe@ellerman.id.au, hch@infradead.org, mikey@neuling.org, npiggin@gmail.com, herbert@gondor.apana.org.au, linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org Cc: sukadev@linux.vnet.ibm.com, hbabu@us.ibm.com Content-Type: text/plain; charset="UTF-8" Date: Sun, 08 Dec 2019 19:18:42 -0800 Message-ID: <1575861522.16318.9.camel@hbabu-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-12-08_07:2019-12-05,2019-12-08 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=2 mlxscore=0 malwarescore=0 clxscore=1011 bulkscore=0 adultscore=0 impostorscore=0 lowpriorityscore=0 spamscore=0 priorityscore=1501 mlxlogscore=999 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1912090028 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Applications will send compression / decompression requests to NX with COPY/PASTE instructions. When NX is processing these requests, can hit fault on the request buffer (not in memory). It issues an interrupt and pastes fault CRB in fault FIFO. Expects kernel to handle this fault and return credits for both send and fault windows after processing. This patch series adds IRQ and fault window setup, and NX fault handling: - Read IRQ# from "interrupts" property and configure IRQ per VAS instance. - Set port# for each window to generate an interrupt when noticed fault. - Set fault window and FIFO on which NX paste fault CRB. - Setup IRQ thread fault handler per VAS instance. - When receiving an interrupt, Read CRBs from fault FIFO and update coprocessor_status_block (CSB) in the corresponding CRB with translation failure (CSB_CC_TRANSLATION). After issuing NX requests, process polls on CSB address. When it sees translation error, can touch the request buffer to bring the page in to memory and reissue NX request. - If copy_to_user fails on user space CSB address, OS sends SEGV signal. Tested these patches with NX-GZIP support and will be posting this series soon. Patch 2: Define nx_fault_stamp on which NX writes fault status for the fault CRB Patch 3: Read interrupts and port properties per VAS instance Patch 4: Setup fault window per each VAS instance. This window is used for NX to paste fault CRB in FIFO. Patches 5 & 6: Setup threaded IRQ per VAS and register NX with fault window ID and port number for each send window so that NX paste fault CRB in this window. Patch 7: Reference to pid and mm so that pid is not used until window closed. Needed for multi thread application where child can open a window and can be used by parent later. Patches 8 and 9: Process CRBs from fault FIFO and notify tasks by updating CSB or through signals. Patches 10 and 11: Return credits for send and fault windows after handling faults. Patch 13:Fix closing send window after all credits are returned. This issue happens only for user space requests. No page faults on kernel request buffer. Changelog: V2: - Use threaded IRQ instead of own kernel thread handler - Use pswid insted of user space CSB address to find valid CRB - Removed unused macros and other changes as suggested by Christoph Hellwig Haren Myneni (13): powerpc/vas: Describe vas-port and interrupts properties powerpc/vas: Define nx_fault_stamp in coprocessor_request_block powerpc/vas: Read interrupts and vas-port device tree properties powerpc/vas: Setup fault window per VAS instance powerpc/vas: Setup thread IRQ handler per VAS instance powerpc/vas: Register NX with fault window ID and IRQ port value powerpc/vas: Take reference to PID and mm for user space windows powerpc/vas: Update CSB and notify process for fault CRBs powerpc/vas: Print CRB and FIFO values powerpc/vas: Do not use default credits for receive window powerpc/VAS: Return credits after handling fault powerpc/vas: Display process stuck message powerpc/vas: Free send window in VAS instance after credits returned .../devicetree/bindings/powerpc/ibm,vas.txt | 5 + arch/powerpc/include/asm/icswx.h | 18 +- arch/powerpc/platforms/powernv/Makefile | 2 +- arch/powerpc/platforms/powernv/vas-debug.c | 2 +- arch/powerpc/platforms/powernv/vas-fault.c | 337 +++++++++++++++++++++ arch/powerpc/platforms/powernv/vas-window.c | 173 ++++++++++- arch/powerpc/platforms/powernv/vas.c | 77 ++++- arch/powerpc/platforms/powernv/vas.h | 38 ++- 8 files changed, 627 insertions(+), 25 deletions(-) create mode 100644 arch/powerpc/platforms/powernv/vas-fault.c -- 1.8.3.1