{"id":2198137,"url":"http://patchwork.ozlabs.org/api/1.0/patches/2198137/?format=json","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.0/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260219130334.787858-6-aesteve@redhat.com>","date":"2026-02-19T13:03:32","name":"[v13,5/7] vhost_user.rst: Add GET_SHMEM_CONFIG message","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"7bc35e73e5c17ced3a9a2e01f594942611d41b65","submitter":{"id":85915,"url":"http://patchwork.ozlabs.org/api/1.0/people/85915/?format=json","name":"Albert Esteve","email":"aesteve@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260219130334.787858-6-aesteve@redhat.com/mbox/","series":[{"id":492672,"url":"http://patchwork.ozlabs.org/api/1.0/series/492672/?format=json","date":"2026-02-19T13:03:27","name":"vhost-user: Add SHMEM_MAP/UNMAP requests","version":13,"mbox":"http://patchwork.ozlabs.org/series/492672/mbox/"}],"check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2198137/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=I1bgcUaD;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n s=mimecast20190719; t=1771506258;\n h=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n to:to:cc:cc:mime-version:mime-version:\n content-transfer-encoding:content-transfer-encoding:\n in-reply-to:in-reply-to:references:references;\n bh=yyDa7teFs3XNo1ZG08MyPTV0M6neQyqQ5iHgVisLshA=;\n b=I1bgcUaDvlY+Cy8sgyXgQLqHgE3rS2jt60mzudvjpaniMEap/kLASaws8NauzhqbxC+NYD\n UHGPRzknpLspx3BWWIe2nFhgS7x2xriz4WQuGLeUtCpJQ+ERUJ/pK+PSi5ftNIUhhALJAr\n 14rkdwbv19VbUh7lrKn0ThWJv/GN18g=","X-MC-Unique":"HdoW9l_pNcqDTN0Bv9KX4Q-1","X-Mimecast-MFC-AGG-ID":"HdoW9l_pNcqDTN0Bv9KX4Q_1771506256","From":"Albert Esteve ","To":"qemu-devel@nongnu.org","Cc":"Peter Xu ,\n Pierrick Bouvier , mst@redhat.com,\n dbassey@redhat.com,\n =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , =?utf-8?q?Alex?=\n\t=?utf-8?q?_Benn=C3=A9e?= ,\n Paolo Bonzini , Fabiano Rosas ,\n stefanha@redhat.com, manos.pitsidianakis@linaro.org,\n Stefano Garzarella , jasowang@redhat.com,\n Laurent Vivier , slp@redhat.com, hi@alyssa.is,\n stevensd@chromium.org","Subject":"[PATCH v13 5/7] vhost_user.rst: Add GET_SHMEM_CONFIG message","Date":"Thu, 19 Feb 2026 14:03:32 +0100","Message-ID":"<20260219130334.787858-6-aesteve@redhat.com>","In-Reply-To":"<20260219130334.787858-1-aesteve@redhat.com>","References":"<20260219130334.787858-1-aesteve@redhat.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Scanned-By":"MIMEDefang 3.0 on 10.30.177.12","Received-SPF":"pass client-ip=170.10.133.124; envelope-from=aesteve@redhat.com;\n helo=us-smtp-delivery-124.mimecast.com","X-Spam_score_int":"-20","X-Spam_score":"-2.1","X-Spam_bar":"--","X-Spam_report":"(-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.045,\n DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001,\n RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001,\n RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001,\n 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":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"Add GET_SHMEM_CONFIG vhost-user frontend\nmessage to the spec documentation.\n\nReviewed-by: Alyssa Ross \nReviewed-by: Stefan Hajnoczi \nSigned-off-by: Albert Esteve \n---\n docs/interop/vhost-user.rst | 39 +++++++++++++++++++++++++++++++++++++\n 1 file changed, 39 insertions(+)","diff":"diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst\nindex ae4ad6f441..77a763c7c3 100644\n--- a/docs/interop/vhost-user.rst\n+++ b/docs/interop/vhost-user.rst\n@@ -371,6 +371,22 @@ MMAP request\n - 0: Pages are mapped read-only\n - 1: Pages are mapped read-write\n \n+VIRTIO Shared Memory Region configuration\n+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n+\n++-------------+---------+------------+----+--------------+\n+| num regions | padding | mem size 0 | .. | mem size 255 |\n++-------------+---------+------------+----+--------------+\n+\n+:num regions: a 32-bit number of regions\n+\n+:padding: 32-bit\n+\n+:mem size: an array of 256 64-bit fields representing the size of each\n+ VIRTIO Shared Memory Region. ``num regions`` specifies the\n+ number of valid regions (non-zero size). The array index\n+ corresponds to the shared memory ID (shmid).\n+\n C structure\n -----------\n \n@@ -397,6 +413,7 @@ In QEMU the vhost-user message is implemented with the following struct:\n VhostUserShared object;\n VhostUserTransferDeviceState transfer_state;\n VhostUserMMap mmap;\n+ VhostUserShMemConfig shmem;\n };\n } QEMU_PACKED VhostUserMsg;\n \n@@ -1761,6 +1778,28 @@ Front-end message types\n Using this function requires prior negotiation of the\n ``VHOST_USER_PROTOCOL_F_DEVICE_STATE`` feature.\n \n+``VHOST_USER_GET_SHMEM_CONFIG``\n+ :id: 44\n+ :equivalent ioctl: N/A\n+ :request payload: N/A\n+ :reply payload: ``struct VhostUserShMemConfig``\n+\n+ When the ``VHOST_USER_PROTOCOL_F_SHMEM`` protocol feature has been\n+ successfully negotiated, this message can be submitted by the front-end\n+ to gather the VIRTIO Shared Memory Region configuration. The back-end will\n+ respond with the number of VIRTIO Shared Memory Regions it requires, and\n+ each shared memory region size in an array. The shared memory IDs are\n+ represented by the array index. The information returned shall comply\n+ with the following rules:\n+\n+ * The shared information will remain valid and unchanged for the entire\n+ lifetime of the connection.\n+\n+ * The Shared Memory Region size must be a multiple of the page size\n+ supported by mmap(2).\n+\n+ * The size may be 0 if the region is unused.\n+\n Back-end message types\n ----------------------\n \n","prefixes":["v13","5/7"]}