From patchwork Wed Nov 27 01:00:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Haren Myneni X-Patchwork-Id: 1201272 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 47N2bV5xXKz9sSZ for ; Wed, 27 Nov 2019 12:04:06 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 47N2bV4JsgzDqjJ for ; Wed, 27 Nov 2019 12:04:06 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=haren@linux.vnet.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 47N2Yl6xqTzDqCh for ; Wed, 27 Nov 2019 12:02:32 +1100 (AEDT) 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 xAR12Kjc039092; Tue, 26 Nov 2019 20:02:22 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2whcxnkpyu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 26 Nov 2019 20:02:22 -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 xAR12LVr039194; Tue, 26 Nov 2019 20:02:21 -0500 Received: from ppma01dal.us.ibm.com (83.d6.3fa9.ip4.static.sl-reverse.com [169.63.214.131]) by mx0a-001b2d01.pphosted.com with ESMTP id 2whcxnkpuh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 26 Nov 2019 20:02:21 -0500 Received: from pps.filterd (ppma01dal.us.ibm.com [127.0.0.1]) by ppma01dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id xAR101BY012324; Wed, 27 Nov 2019 01:02:10 GMT Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by ppma01dal.us.ibm.com with ESMTP id 2wevd6rar3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 27 Nov 2019 01:02:10 +0000 Received: from b01ledav004.gho.pok.ibm.com (b01ledav004.gho.pok.ibm.com [9.57.199.109]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xAR12AwV39256500 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 27 Nov 2019 01:02:10 GMT Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E9F97112063; Wed, 27 Nov 2019 01:02:09 +0000 (GMT) Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3C5F4112062; Wed, 27 Nov 2019 01:02:09 +0000 (GMT) Received: from [9.70.82.143] (unknown [9.70.82.143]) by b01ledav004.gho.pok.ibm.com (Postfix) with ESMTP; Wed, 27 Nov 2019 01:02:09 +0000 (GMT) Subject: [PATCH 00/14] powerpc/vas: Page fault handling for user space NX requests From: Haren Myneni To: linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org, mpe@ellerman.id.au, npiggin@gmail.com, mikey@neuling.org, herbert@gondor.apana.org.au Date: Tue, 26 Nov 2019 17:00:50 -0800 Message-ID: <1574816450.13250.2.camel@hbabu-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95, 18.0.572 definitions=2019-11-26_08:2019-11-26, 2019-11-26 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 mlxscore=0 phishscore=0 lowpriorityscore=0 priorityscore=1501 suspectscore=2 bulkscore=0 impostorscore=0 spamscore=0 clxscore=1011 malwarescore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1911270006 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: sukadev@linux.vnet.ibm.com Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Applications 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 fault handler (as kernel thread) 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: Revert 452d23c0f6bd97f2 - Using vas_win_id() and vas_win_paste_addr() Patch 3: Define nx_fault_stamp on which NX writes fault status for the fault CRB Patch 4: IRQ and port setup Patches 5 and 6: Setup fault window and fault handler per each VAS instance. fault window is used for NX to paste fault CRB in FIFO. A kernel thread is created to handle faults on each VAS. Patches 7, 9 and 10: Read and process CRBs from fault FIFO and notify tasks by updating CSB or through signals. Patch 8: Reference to pid and mm so that pid is not used until window closed. Needef for multi thread application where child can open a window and can be used by parent later. Patches 11 and 12: Return credits for send and fault windows after handling faults. Patch 14: Fix closing send window after all credits are returned. This issue happens only for user space requests. No page faults on kernel request buffer. Haren Myneni (14): powerpc/vas: Describe vas-port and interrupts properties Revert "powerpc/powernv: remove the unused vas_win_paste_addr and vas_win_id functions" powerpc/vas: Define nx_fault_stamp in coprocessor_request_block powerpc/vas: Setup IRQ mapping and register port for each window powerpc/vas: Setup fault window per VAS instance powerpc/VAS: Setup fault handler per VAS instance powerpc/vas: Read and process fault CRBs 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 | 32 +- arch/powerpc/include/asm/vas.h | 10 + arch/powerpc/platforms/powernv/Makefile | 2 +- arch/powerpc/platforms/powernv/vas-debug.c | 2 +- arch/powerpc/platforms/powernv/vas-fault.c | 408 +++++++++++++++++++++ arch/powerpc/platforms/powernv/vas-window.c | 192 +++++++++- arch/powerpc/platforms/powernv/vas.c | 87 ++++- arch/powerpc/platforms/powernv/vas.h | 54 ++- 9 files changed, 769 insertions(+), 23 deletions(-) create mode 100644 arch/powerpc/platforms/powernv/vas-fault.c