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 E799CC43603 for ; Thu, 12 Dec 2019 05:40:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B177D2073D for ; Thu, 12 Dec 2019 05:40:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726880AbfLLFki (ORCPT ); Thu, 12 Dec 2019 00:40:38 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:9346 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725980AbfLLFki (ORCPT ); Thu, 12 Dec 2019 00:40:38 -0500 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xBC5b3qI136872; Thu, 12 Dec 2019 00:40:17 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2wtfby7q1j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 12 Dec 2019 00:40:17 -0500 Received: from m0098396.ppops.net (m0098396.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id xBC5bQHY137787; Thu, 12 Dec 2019 00:40:16 -0500 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 2wtfby7q17-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 12 Dec 2019 00:40:16 -0500 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id xBC5YwdO004715; Thu, 12 Dec 2019 05:40:15 GMT Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by ppma03dal.us.ibm.com with ESMTP id 2wr3q7wxum-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 12 Dec 2019 05:40:15 +0000 Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xBC5eEcG41419166 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 12 Dec 2019 05:40:14 GMT Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9E84C6A054; Thu, 12 Dec 2019 05:40:14 +0000 (GMT) Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1E11C6A04D; Thu, 12 Dec 2019 05:40:13 +0000 (GMT) Received: from [9.70.82.143] (unknown [9.70.82.143]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP; Thu, 12 Dec 2019 05:40:13 +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 Cc: hch@infradead.org, mikey@neuling.org, npiggin@gmail.com, herbert@gondor.apana.org.au, linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org, sukadev@linux.vnet.ibm.com In-Reply-To: <1575861522.16318.9.camel@hbabu-laptop> References: <1575861522.16318.9.camel@hbabu-laptop> Content-Type: text/plain; charset="UTF-8" Date: Wed, 11 Dec 2019 21:38:30 -0800 Message-ID: <1576129110.16318.48.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=2019-12-12_01:2019-12-12,2019-12-11 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=3 spamscore=0 mlxlogscore=999 malwarescore=0 phishscore=0 priorityscore=1501 bulkscore=0 adultscore=0 mlxscore=0 lowpriorityscore=0 clxscore=1015 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1912120035 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org [PATCH V2 00/13] powerpc/vas: Page fault handling for user space NX requests On power9, Virtual Accelerator Switchboard (VAS) allows user space or kernel to communicate with Nest Accelerator (NX) directly using COPY/PASTE instructions. NX provides verious functionalities such as compression, encryption and etc. But only compression (842 and GZIP formats) is supported in Linux kernel on power9. 842 compression driver (drivers/crypto/nx/nx-842-powernv.c) is already included in Linux. Only GZIP support will be available from user space. Applications can issue GZIP 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