From patchwork Sat Mar 4 01:06:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elliot Berman X-Patchwork-Id: 659424 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D7177C64EC4 for ; Sat, 4 Mar 2023 01:35:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229586AbjCDBfu (ORCPT ); Fri, 3 Mar 2023 20:35:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229484AbjCDBft (ORCPT ); Fri, 3 Mar 2023 20:35:49 -0500 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA6E364A88; Fri, 3 Mar 2023 17:35:47 -0800 (PST) Received: from pps.filterd (m0279869.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3240r4ow007584; Sat, 4 Mar 2023 01:07:24 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=qcppdkim1; bh=wvhDtInPmC0leqk/Kbs8lbSLrxQCbpRgDn//zaKP+3A=; b=N4QIX8FVeV//H/Tk6LCPslaXvPIyP/w97rv2LggkAF+fdV9KtVgsNEeMFK5VCWd+wx5U aJAt8n7ppAp3cAEUXdJ4O+wl7AVblYvqdHA5R7ivr5utiCGoLHSrU8nifzhybmWxrsxW iuIV5gB6gSI3iq46OXwcdp9KQlS5rT6OciIqjViCqaHcXoE+K/ixRyLy5Cr2xbhfG8md oLHR2J93mFuJHsm6O6sz6tAJe5xqtO+JBsy6Rny40zBLeTn+PBzDkUv/V0+E6Zl0q+2F QtZB6tDmhM8kBI7J6BYtf+vGv4vZbJy3II/qdS4H05jOqU5n3546zPprMqBdey53d4Iv Ow== Received: from nasanppmta04.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3p32ty430h-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 04 Mar 2023 01:07:23 +0000 Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA04.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 32417Mmd019390 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 4 Mar 2023 01:07:22 GMT Received: from hu-eberman-lv.qualcomm.com (10.49.16.6) by nasanex01b.na.qualcomm.com (10.46.141.250) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.41; Fri, 3 Mar 2023 17:07:22 -0800 From: Elliot Berman To: Alex Elder , Srinivas Kandagatla , Elliot Berman , Prakruthi Deepak Heragu , Jonathan Corbet CC: Murali Nalajala , Trilok Soni , Srivatsa Vaddagiri , Carl van Schaik , Dmitry Baryshkov , Bjorn Andersson , "Konrad Dybcio" , Arnd Bergmann , "Greg Kroah-Hartman" , Rob Herring , Krzysztof Kozlowski , Bagas Sanjaya , Will Deacon , Andy Gross , Catalin Marinas , Jassi Brar , , , , , Subject: [PATCH v11 25/26] virt: gunyah: Add ioeventfd Date: Fri, 3 Mar 2023 17:06:31 -0800 Message-ID: <20230304010632.2127470-26-quic_eberman@quicinc.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230304010632.2127470-1-quic_eberman@quicinc.com> References: <20230304010632.2127470-1-quic_eberman@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.49.16.6] X-ClientProxiedBy: nalasex01c.na.qualcomm.com (10.47.97.35) To nasanex01b.na.qualcomm.com (10.46.141.250) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: 0ezja0ChU0czpuzouca54EhuQjAyN310 X-Proofpoint-ORIG-GUID: 0ezja0ChU0czpuzouca54EhuQjAyN310 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-03-03_07,2023-03-03_01,2023-02-09_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 spamscore=0 mlxlogscore=999 lowpriorityscore=0 suspectscore=0 mlxscore=0 priorityscore=1501 malwarescore=0 adultscore=0 impostorscore=0 phishscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2212070000 definitions=main-2303040004 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Allow userspace to attach an ioeventfd to an mmio address within the guest. Co-developed-by: Prakruthi Deepak Heragu Signed-off-by: Prakruthi Deepak Heragu Signed-off-by: Elliot Berman --- Documentation/virt/gunyah/vm-manager.rst | 2 +- drivers/virt/gunyah/Kconfig | 9 ++ drivers/virt/gunyah/Makefile | 1 + drivers/virt/gunyah/gunyah_ioeventfd.c | 117 +++++++++++++++++++++++ include/uapi/linux/gunyah.h | 37 +++++++ 5 files changed, 165 insertions(+), 1 deletion(-) create mode 100644 drivers/virt/gunyah/gunyah_ioeventfd.c diff --git a/Documentation/virt/gunyah/vm-manager.rst b/Documentation/virt/gunyah/vm-manager.rst index a1dd70f0cbf6..cd41a705849f 100644 --- a/Documentation/virt/gunyah/vm-manager.rst +++ b/Documentation/virt/gunyah/vm-manager.rst @@ -124,7 +124,7 @@ the VM starts. The possible types are documented below: .. kernel-doc:: include/uapi/linux/gunyah.h - :identifiers: GH_FN_VCPU gh_fn_vcpu_arg GH_FN_IRQFD gh_fn_irqfd_arg + :identifiers: GH_FN_VCPU gh_fn_vcpu_arg GH_FN_IRQFD gh_fn_irqfd_arg GH_FN_IOEVENTFD gh_fn_ioeventfd_arg Gunyah VCPU API Descriptions ---------------------------- diff --git a/drivers/virt/gunyah/Kconfig b/drivers/virt/gunyah/Kconfig index 2cde24d429d1..bd8e31184962 100644 --- a/drivers/virt/gunyah/Kconfig +++ b/drivers/virt/gunyah/Kconfig @@ -35,3 +35,12 @@ config GUNYAH_IRQFD on Gunyah virtual machine. Say Y/M here if unsure and you want to support Gunyah VMMs. + +config GUNYAH_IOEVENTFD + tristate "Gunyah ioeventfd interface" + depends on GUNYAH + help + Enable kernel support for creating ioeventfds which can alert userspace + when a Gunyah virtual machine accesses a memory address. + + Say Y/M here if unsure and you want to support Gunyah VMMs. diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile index 6cf756bfa3c2..7347b1470491 100644 --- a/drivers/virt/gunyah/Makefile +++ b/drivers/virt/gunyah/Makefile @@ -8,3 +8,4 @@ obj-$(CONFIG_GUNYAH) += gunyah_rsc_mgr.o obj-$(CONFIG_GUNYAH_VCPU) += gunyah_vcpu.o obj-$(CONFIG_GUNYAH_IRQFD) += gunyah_irqfd.o +obj-$(CONFIG_GUNYAH_IOEVENTFD) += gunyah_ioeventfd.o diff --git a/drivers/virt/gunyah/gunyah_ioeventfd.c b/drivers/virt/gunyah/gunyah_ioeventfd.c new file mode 100644 index 000000000000..517f55706ed9 --- /dev/null +++ b/drivers/virt/gunyah/gunyah_ioeventfd.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include + +struct gh_ioeventfd { + struct gh_vm_function_instance *f; + struct gh_vm_io_handler io_handler; + + struct eventfd_ctx *ctx; +}; + +static int gh_write_ioeventfd(struct gh_vm_io_handler *io_dev, u64 addr, u32 len, u64 data) +{ + struct gh_ioeventfd *iofd = container_of(io_dev, struct gh_ioeventfd, io_handler); + + eventfd_signal(iofd->ctx, 1); + return 0; +} + +static struct gh_vm_io_handler_ops io_ops = { + .write = gh_write_ioeventfd, +}; + +static long gh_ioeventfd_bind(struct gh_vm_function_instance *f) +{ + const struct gh_fn_ioeventfd_arg *args = f->argp; + struct eventfd_ctx *ctx = NULL; + struct gh_ioeventfd *iofd; + int ret; + + if (f->arg_size != sizeof(*args)) + return -EINVAL; + + /* must be natural-word sized, or 0 to ignore length */ + switch (args->len) { + case 0: + case 1: + case 2: + case 4: + case 8: + break; + default: + return -EINVAL; + } + + /* check for range overflow */ + if (args->addr + args->len < args->addr) + return -EINVAL; + + /* ioeventfd with no length can't be combined with DATAMATCH */ + if (!args->len && (args->flags & GH_IOEVENTFD_DATAMATCH)) + return -EINVAL; + + /* All other flag bits are reserved for future use */ + if (args->flags & ~GH_IOEVENTFD_DATAMATCH) + return -EINVAL; + + ctx = eventfd_ctx_fdget(args->fd); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); + + iofd = kzalloc(sizeof(*iofd), GFP_KERNEL); + if (!iofd) { + ret = -ENOMEM; + goto err_eventfd; + } + + f->data = iofd; + iofd->f = f; + + iofd->ctx = ctx; + + if (args->flags & GH_IOEVENTFD_DATAMATCH) { + iofd->io_handler.datamatch = true; + iofd->io_handler.len = args->len; + iofd->io_handler.data = args->datamatch; + } + iofd->io_handler.addr = args->addr; + iofd->io_handler.ops = &io_ops; + + ret = gh_vm_add_io_handler(f->ghvm, &iofd->io_handler); + if (ret) + goto err_io_dev_add; + + return 0; + +err_io_dev_add: + kfree(iofd); +err_eventfd: + eventfd_ctx_put(ctx); + return ret; +} + +static void gh_ioevent_unbind(struct gh_vm_function_instance *f) +{ + struct gh_ioeventfd *iofd = f->data; + + eventfd_ctx_put(iofd->ctx); + gh_vm_remove_io_handler(iofd->f->ghvm, &iofd->io_handler); + kfree(iofd); +} + +DECLARE_GH_VM_FUNCTION_INIT(ioeventfd, GH_FN_IOEVENTFD, + gh_ioeventfd_bind, gh_ioevent_unbind); +MODULE_DESCRIPTION("Gunyah ioeventfds"); +MODULE_LICENSE("GPL"); diff --git a/include/uapi/linux/gunyah.h b/include/uapi/linux/gunyah.h index 5617dadc1c7b..f8482ff4cc55 100644 --- a/include/uapi/linux/gunyah.h +++ b/include/uapi/linux/gunyah.h @@ -89,6 +89,23 @@ struct gh_vm_dtb_config { */ #define GH_FN_IRQFD 2 +/** + * GH_FN_IOEVENTFD - register ioeventfd to trigger when VM faults on parameter + * + * gh_fn_desc is filled with gh_fn_ioeventfd_arg + * + * Attaches an ioeventfd to a legal mmio address within the guest. A guest write + * in the registered address will signal the provided event instead of triggering + * an exit on the GH_VCPU_RUN ioctl. + * + * If GH_IOEVENTFD_DATAMATCH flag is set, the event will be signaled only if the + * written value to the registered address is equal to datamatch in + * struct gh_fn_ioeventfd_arg. + * + * Return: 0 + */ +#define GH_FN_IOEVENTFD 3 + #define GH_FN_MAX_ARG_SIZE 256 /** @@ -118,6 +135,26 @@ struct gh_fn_irqfd_arg { #define GH_IOEVENTFD_DATAMATCH (1UL << 0) +/** + * struct gh_fn_ioeventfd_arg - Arguments to create an ioeventfd function + * @datamatch: data used when GH_IOEVENTFD_DATAMATCH is set + * @addr: Address in guest memory + * @len: Length of access + * @fd: When ioeventfd is matched, this eventfd is written + * @flags: If GH_IOEVENTFD_DATAMATCH flag is set, the event will be signaled + * only if the written value to the registered address is equal to + * @datamatch + * @padding: padding bytes + */ +struct gh_fn_ioeventfd_arg { + __u64 datamatch; + __u64 addr; /* legal mmio address */ + __u32 len; /* 1, 2, 4, or 8 bytes; or 0 to ignore length */ + __s32 fd; + __u32 flags; + __u32 padding; +}; + /** * struct gh_fn_desc - Arguments to create a VM function * @type: Type of the function. See GH_FN_* macro for supported types