From patchwork Mon Dec 19 22:58:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elliot Berman X-Patchwork-Id: 13077247 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 41F6DC4167B for ; Mon, 19 Dec 2022 23:05:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233194AbiLSXFj (ORCPT ); Mon, 19 Dec 2022 18:05:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53926 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232975AbiLSXDh (ORCPT ); Mon, 19 Dec 2022 18:03:37 -0500 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98D0F167F6; Mon, 19 Dec 2022 15:01:10 -0800 (PST) Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2BJMeVG3024916; Mon, 19 Dec 2022 23:00:58 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=7FMfLEKP9dRSF/3+r3eP1XbMU6ePBkPsOZAopXAWIMk=; b=ii9DQc6HTLemeJzW6kFPKi8U7/UnS+Tg4cNCJz6u8tDGJo+Tr03DNVOCJDaoyAXLzBsq uVNv0DdDs+R7zvVycbUNPN2fGwZTWFeB0Zdfi0mpM8uWdneA73tJkuI1ejv9UB5G3AxB d8GKTpKxKS+xLa0gGnVVbnKR7THHkgyTP0zxH4+papcecHye49ooqVX9yGUw/cGQjfWR KgesPesptuHkYoagBNIP2kzVj9NbBeKrlkZ5DhR3tu2tld0gHasAfyUyd5oMo4L9+ZaY LHAq+xSN5Vf+wnQd/OhbkHStMzLkmayyGJYRwWA6R5IXFTBYne6AWGfP0FRvK7YZ6FEP BA== Received: from nasanppmta01.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3mjkwqsk84-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 19 Dec 2022 23:00:58 +0000 Received: from nasanex01b.na.qualcomm.com (corens_vlan604_snip.qualcomm.com [10.53.140.1]) by NASANPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 2BJN0vXx007500 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 19 Dec 2022 23:00:57 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 15.2.986.36; Mon, 19 Dec 2022 15:00:56 -0800 From: Elliot Berman To: Bjorn Andersson , Elliot Berman , Murali Nalajala , Jonathan Corbet CC: Trilok Soni , Srivatsa Vaddagiri , Carl van Schaik , Prakruthi Deepak Heragu , Arnd Bergmann , Greg Kroah-Hartman , Rob Herring , Krzysztof Kozlowski , Bagas Sanjaya , Catalin Marinas , Will Deacon , Jassi Brar , Sudeep Holla , Mark Rutland , Lorenzo Pieralisi , Dmitry Baryshkov , , , , , , Subject: [PATCH v8 28/28] virt: gunyah: Add ioeventfd Date: Mon, 19 Dec 2022 14:58:49 -0800 Message-ID: <20221219225850.2397345-29-quic_eberman@quicinc.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221219225850.2397345-1-quic_eberman@quicinc.com> References: <20221219225850.2397345-1-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: jZDMPj5TsLWgw0k0ut_Eihl9iuVeE-lt X-Proofpoint-ORIG-GUID: jZDMPj5TsLWgw0k0ut_Eihl9iuVeE-lt X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.923,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-12-19_01,2022-12-15_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 mlxscore=0 priorityscore=1501 spamscore=0 mlxlogscore=999 lowpriorityscore=0 suspectscore=0 impostorscore=0 phishscore=0 bulkscore=0 adultscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2212070000 definitions=main-2212190202 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 | 21 +++++ drivers/virt/gunyah/Kconfig | 10 +++ drivers/virt/gunyah/Makefile | 1 + drivers/virt/gunyah/gunyah_ioeventfd.c | 109 +++++++++++++++++++++++ include/uapi/linux/gunyah.h | 10 +++ 5 files changed, 151 insertions(+) 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 b6cf8db826b8..19ec859a7912 100644 --- a/Documentation/virt/gunyah/vm-manager.rst +++ b/Documentation/virt/gunyah/vm-manager.rst @@ -164,3 +164,24 @@ the irqfd.label. GH_IRQFD_LEVEL configures the corresponding doorbell to behave like a level triggered interrupt. + +Type: "ioeventfd" +^^^^^^^^^^^^^^^^^ + +:: + + struct gh_fn_ioeventfd_arg { + __u64 datamatch; + __u64 addr; /* legal mmio address */ + __u32 len; /* 1, 2, 4, or 8 bytes */ + __s32 fd; + #define GH_IOEVENTFD_DATAMATCH (1UL << 0) + __u32 flags; + }; + +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 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. diff --git a/drivers/virt/gunyah/Kconfig b/drivers/virt/gunyah/Kconfig index 42842e755a04..06f1082f98f0 100644 --- a/drivers/virt/gunyah/Kconfig +++ b/drivers/virt/gunyah/Kconfig @@ -59,5 +59,15 @@ config GUNYAH_IRQFD Enable kernel support for creating irqfds which can raise an interrupt 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_RESOURCE_MANAGER + depends on GUNYAH_VM_MANAGER + 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. endif diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile index 065eeb060597..bcffb99eb28f 100644 --- a/drivers/virt/gunyah/Makefile +++ b/drivers/virt/gunyah/Makefile @@ -7,3 +7,4 @@ obj-$(CONFIG_GUNYAH_RESOURCE_MANAGER) += gunyah_rsc_mgr.o obj-$(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..5f43057eb768 --- /dev/null +++ b/drivers/virt/gunyah/gunyah_ioeventfd.c @@ -0,0 +1,109 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include + +struct gunyah_ioeventfd { + struct gunyah_vm_function *f; + struct gunyah_vm_io_handler io_handler; + + struct eventfd_ctx *ctx; +}; + +static int gh_write_ioeventfd(struct gunyah_vm_io_handler *io_dev, u64 addr, u32 len, u64 data) +{ + struct gunyah_ioeventfd *iofd = container_of(io_dev, struct gunyah_ioeventfd, io_handler); + + eventfd_signal(iofd->ctx, 1); + return 0; +} + +static struct gunyah_vm_io_handler_ops io_ops = { + .write = gh_write_ioeventfd, +}; + +static long gunyah_ioeventfd_bind(struct gunyah_vm_function *f) +{ + struct eventfd_ctx *ctx = NULL; + struct gunyah_ioeventfd *iofd; + const struct gh_fn_ioeventfd_arg *args = &f->fn.ioeventfd; + int ret; + + /* 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; + + 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_mgr_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 gunyah_ioeventfd_release(struct gunyah_vm_function *f) +{ + struct gunyah_ioeventfd *iofd = f->data; + + eventfd_ctx_put(iofd->ctx); + gh_vm_mgr_remove_io_handler(iofd->f->ghvm, &iofd->io_handler); + kfree(iofd); +} + +DECLARE_GUNYAH_VM_FUNCTION_INIT(ioeventfd, gunyah_ioeventfd_bind, gunyah_ioeventfd_release); +MODULE_DESCRIPTION("Gunyah ioeventfds"); +MODULE_LICENSE("GPL"); diff --git a/include/uapi/linux/gunyah.h b/include/uapi/linux/gunyah.h index 5eab212c7bf5..5da9fb933bae 100644 --- a/include/uapi/linux/gunyah.h +++ b/include/uapi/linux/gunyah.h @@ -65,11 +65,21 @@ struct gh_fn_irqfd_arg { __u32 flags; }; +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; +#define GH_IOEVENTFD_DATAMATCH (1UL << 0) + __u32 flags; +}; + struct gh_vm_function { char name[GUNYAH_FUNCTION_NAME_SIZE]; union { struct gh_fn_vcpu_arg vcpu; struct gh_fn_irqfd_arg irqfd; + struct gh_fn_ioeventfd_arg ioeventfd; char data[GUNYAH_FUNCTION_MAX_ARG_SIZE]; }; };