From nobody Sat Nov 15 14:52:42 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=linux.microsoft.com ARC-Seal: i=1; a=rsa-sha256; t=1751391367; cv=none; d=zohomail.com; s=zohoarc; b=ktQglB9XLgXMJR6oyFdd28sU1cj5ObKvq63wwYCv/BKnavornLd7OHels4biLsBY+eS6p8/cb2N2wyLnUdz3PmifKVJISUup/U/cB+ts2EI563W3JtQfZfpTN5rxePaQiFqSQ08fM87QQQW/nCnGsek5xaLsn0xc9LD8sLlwjEw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1751391367; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=Y4vhPW1L/apWF7A2PygowCDp5jO99b8a9HgfYCjLboI=; b=D7Mv3wq8uoEpg+vZOt+RM5Gj3d/B7iVndjgj8fpQ+wCjQRjmzRTi9eEFrRJO/BsU0r4nsgKw8+7Bi+oLYzMd3QKCw6nX/sOPU6l1fW2BhQ7uVf7ATRIU1yNs3W1AdwBDxocrDIEYZsZZWihTqrb7iyP1wOGF22TGNozhaotpuIA= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 175139136765464.70023587687115; Tue, 1 Jul 2025 10:36:07 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uWenl-0003y7-IG; Tue, 01 Jul 2025 13:29:49 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uWenj-0003np-Mp for qemu-devel@nongnu.org; Tue, 01 Jul 2025 13:29:47 -0400 Received: from linux.microsoft.com ([13.77.154.182]) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uWeng-0006ln-5d for qemu-devel@nongnu.org; Tue, 01 Jul 2025 13:29:47 -0400 Received: from localhost.localdomain (unknown [167.220.208.67]) by linux.microsoft.com (Postfix) with ESMTPSA id 6F53C2112236; Tue, 1 Jul 2025 10:29:39 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 6F53C2112236 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1751390983; bh=Y4vhPW1L/apWF7A2PygowCDp5jO99b8a9HgfYCjLboI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hycZXmQZF60SDp6nNrn1MYE18EJXtTfFFU1NarpNWbg/EuM1KC/ZhBIzdniwggSjb gwM7RytFV6O74eg37fLRDjm83RSdohXNxDZLe0Q2gaJwVGadaD7qNoqbkgqQ3mVLtK SjxAYfdzQx6gKJmawKtjpV3wltEo50cWmZ0S2Z08= From: Magnus Kulke To: qemu-devel@nongnu.org Cc: Cameron Esfahani , Phil Dennis-Jordan , Roman Bolshakov , Thomas Huth , Zhao Liu , Wei Liu , Paolo Bonzini , Wei Liu , Richard Henderson , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Markus Armbruster , Cornelia Huck , Magnus Kulke , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , "Michael S. Tsirkin" , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , =?UTF-8?q?Alex=20Benn=C3=A9e?= Subject: [PATCH v2 10/27] accel/mshv: Add ioeventfd support Date: Tue, 1 Jul 2025 19:28:17 +0200 Message-Id: <20250701172834.44849-11-magnuskulke@linux.microsoft.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250701172834.44849-1-magnuskulke@linux.microsoft.com> References: <20250701172834.44849-1-magnuskulke@linux.microsoft.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=13.77.154.182; envelope-from=magnuskulke@linux.microsoft.com; helo=linux.microsoft.com X-Spam_score_int: -19 X-Spam_score: -2.0 X-Spam_bar: -- X-Spam_report: (-2.0 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @linux.microsoft.com) X-ZM-MESSAGEID: 1751391368437116600 Content-Type: text/plain; charset="utf-8" Implement ioeventfd registration in the MSHV accelerator backend to handle guest-triggered events. This enables integration with QEMU's eventfd-based I/O mechanism. Signed-off-by: Magnus Kulke --- accel/mshv/mshv-all.c | 116 ++++++++++++++++++++++++++++++++++++++++ accel/mshv/trace-events | 3 ++ include/system/mshv.h | 8 +++ 3 files changed, 127 insertions(+) diff --git a/accel/mshv/mshv-all.c b/accel/mshv/mshv-all.c index 712e651627..2ae9d1cffa 100644 --- a/accel/mshv/mshv-all.c +++ b/accel/mshv/mshv-all.c @@ -7,6 +7,7 @@ * Ziqiao Zhou * Magnus Kulke * Jinank Jain + * Wei Liu * * This work is licensed under the terms of the GNU GPL, version 2 or late= r. * See the COPYING file in the top-level directory. @@ -236,11 +237,126 @@ static void mem_region_del(MemoryListener *listener, memory_region_unref(section->mr); } =20 +typedef enum { + DATAMATCH_NONE, + DATAMATCH_U32, + DATAMATCH_U64, +} DatamatchTag; + +typedef struct { + DatamatchTag tag; + union { + uint32_t u32; + uint64_t u64; + } value; +} Datamatch; + +/* flags: determine whether to de/assign */ +static int ioeventfd(int vm_fd, int event_fd, uint64_t addr, Datamatch dm, + uint32_t flags) +{ + mshv_user_ioeventfd args =3D {0}; + args.fd =3D event_fd; + args.addr =3D addr; + args.flags =3D flags; + + if (dm.tag =3D=3D DATAMATCH_NONE) { + args.datamatch =3D 0; + } else { + flags |=3D BIT(MSHV_IOEVENTFD_BIT_DATAMATCH); + args.flags =3D flags; + if (dm.tag =3D=3D DATAMATCH_U64) { + args.len =3D sizeof(uint64_t); + args.datamatch =3D dm.value.u64; + } else { + args.len =3D sizeof(uint32_t); + args.datamatch =3D dm.value.u32; + } + } + + return ioctl(vm_fd, MSHV_IOEVENTFD, &args); +} + +static int unregister_ioevent(int vm_fd, int event_fd, uint64_t mmio_addr) +{ + uint32_t flags =3D 0; + Datamatch dm =3D {0}; + + flags |=3D BIT(MSHV_IOEVENTFD_BIT_DEASSIGN); + dm.tag =3D DATAMATCH_NONE; + + return ioeventfd(vm_fd, event_fd, mmio_addr, dm, flags); +} + +static int register_ioevent(int vm_fd, int event_fd, uint64_t mmio_addr, + uint64_t val, bool is_64bit, bool is_datamatch) +{ + uint32_t flags =3D 0; + Datamatch dm =3D {0}; + + if (!is_datamatch) { + dm.tag =3D DATAMATCH_NONE; + } else if (is_64bit) { + dm.tag =3D DATAMATCH_U64; + dm.value.u64 =3D val; + } else { + dm.tag =3D DATAMATCH_U32; + dm.value.u32 =3D val; + } + + return ioeventfd(vm_fd, event_fd, mmio_addr, dm, flags); +} + +static void mem_ioeventfd_add(MemoryListener *listener, + MemoryRegionSection *section, + bool match_data, uint64_t data, + EventNotifier *e) +{ + int fd =3D event_notifier_get_fd(e); + int ret; + bool is_64 =3D int128_get64(section->size) =3D=3D 8; + uint64_t addr =3D section->offset_within_address_space; + + trace_mshv_mem_ioeventfd_add(addr, int128_get64(section->size), data); + + ret =3D register_ioevent(mshv_state->vm, fd, addr, data, is_64, match_= data); + + if (ret < 0) { + error_report("Failed to register ioeventfd: %s (%d)", strerror(-re= t), + -ret); + abort(); + } +} + +static void mem_ioeventfd_del(MemoryListener *listener, + MemoryRegionSection *section, + bool match_data, uint64_t data, + EventNotifier *e) +{ + int fd =3D event_notifier_get_fd(e); + int ret; + uint64_t addr =3D section->offset_within_address_space; + + trace_mshv_mem_ioeventfd_del(section->offset_within_address_space, + int128_get64(section->size), data); + + ret =3D unregister_ioevent(mshv_state->vm, fd, addr); + if (ret < 0) { + error_report("Failed to unregister ioeventfd: %s (%d)", strerror(-= ret), + -ret); + abort(); + } +} + static MemoryListener mshv_memory_listener =3D { .name =3D "mshv", .priority =3D MEMORY_LISTENER_PRIORITY_ACCEL, .region_add =3D mem_region_add, .region_del =3D mem_region_del, +#ifdef MSHV_USE_IOEVENTFD + .eventfd_add =3D mem_ioeventfd_add, + .eventfd_del =3D mem_ioeventfd_del, +#endif }; =20 static MemoryListener mshv_io_listener =3D { diff --git a/accel/mshv/trace-events b/accel/mshv/trace-events index 9a3af6b8be..b49a5b1702 100644 --- a/accel/mshv/trace-events +++ b/accel/mshv/trace-events @@ -1,6 +1,9 @@ # See docs/devel/tracing.rst for syntax documentation. =20 mshv_set_memory(bool add, uint64_t gpa, uint64_t size, uint64_t user_addr,= bool readonly, int ret) "[add =3D %d] gpa =3D %lx size =3D %lx user =3D %l= x readonly =3D %d result =3D %d" +mshv_mem_ioeventfd_add(uint64_t addr, uint32_t size, uint32_t data) "addr = %lx size %d data %x" +mshv_mem_ioeventfd_del(uint64_t addr, uint32_t size, uint32_t data) "addr = %lx size %d data %x" + mshv_hvcall_args(const char* hvcall, uint16_t code, uint16_t in_sz) "built= args for '%s' code: %d in_sz: %d" =20 mshv_set_msi_routing(uint32_t gsi, uint64_t addr, uint32_t data) "gsi=3D%d= addr=3D%lx data=3D%x" diff --git a/include/system/mshv.h b/include/system/mshv.h index 3624d9477f..c2b0414c85 100644 --- a/include/system/mshv.h +++ b/include/system/mshv.h @@ -30,6 +30,14 @@ #define CONFIG_MSHV_IS_POSSIBLE #endif =20 +/* + * Set to 0 if we do not want to use eventfd to optimize the MMIO events. + * Set to 1 so that mshv kernel driver receives doorbell when the VM access + * MMIO memory and then signal eventfd to notify the qemu device + * without extra switching to qemu to emulate mmio access. + */ +#define MSHV_USE_IOEVENTFD 1 + #define MSHV_PAGE_SHIFT 12 =20 #ifdef CONFIG_MSHV_IS_POSSIBLE --=20 2.34.1