From mboxrd@z Thu Jan 1 00:00:00 1970 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 60AF0C4321E for ; Mon, 5 Dec 2022 13:51:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231544AbiLENvn (ORCPT ); Mon, 5 Dec 2022 08:51:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230385AbiLENvi (ORCPT ); Mon, 5 Dec 2022 08:51:38 -0500 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 02A0A1D0CE for ; Mon, 5 Dec 2022 05:51:36 -0800 (PST) Received: from kwepemi100025.china.huawei.com (unknown [172.30.72.57]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4NQlHT3qPGzkXnk; Mon, 5 Dec 2022 21:48:05 +0800 (CST) Received: from DESKTOP-27KDQMV.china.huawei.com (10.174.148.223) by kwepemi100025.china.huawei.com (7.221.188.158) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 5 Dec 2022 21:51:33 +0800 From: "Longpeng(Mike)" To: , , , , CC: , , , , , , Longpeng Subject: [PATCH v2] vdpasim: support doorbell mapping Date: Mon, 5 Dec 2022 21:51:30 +0800 Message-ID: <20221205135130.2336-1-longpeng2@huawei.com> X-Mailer: git-send-email 2.25.0.windows.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.174.148.223] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemi100025.china.huawei.com (7.221.188.158) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Longpeng Support doorbell mapping for vdpasim devices, then we can test the notify passthrough feature even if there's no real hardware on hand. Allocates a dummy page which is used to emulate the notify page of the device, all VQs share the same notify register that initiated to 0xffff. A periodic work will check whether there're requests need to process ( the value of the notify register is 0xffff or not ). This cap is disabled as default, users can enable it as follow: modprobe vdpa_sim notify_passthrough=true Signed-off-by: Longpeng --- Changes v1->v2: - support both kick mode and passthrough mode. [Jason] - poll the notify register first. [Jason, Michael] --- drivers/vdpa/vdpa_sim/vdpa_sim.c | 77 ++++++++++++++++++++++++++++++++ drivers/vdpa/vdpa_sim/vdpa_sim.h | 3 ++ 2 files changed, 80 insertions(+) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c index 7438a89ce939..07096a04dabb 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -36,9 +37,16 @@ module_param(max_iotlb_entries, int, 0444); MODULE_PARM_DESC(max_iotlb_entries, "Maximum number of iotlb entries for each address space. 0 means unlimited. (default: 2048)"); +static bool notify_passthrough; +module_param(notify_passthrough, bool, 0444); +MODULE_PARM_DESC(notify_passthrough, + "Enable vq notify(doorbell) area mapping. (default: false)"); + #define VDPASIM_QUEUE_ALIGN PAGE_SIZE #define VDPASIM_QUEUE_MAX 256 #define VDPASIM_VENDOR_ID 0 +#define VDPASIM_VRING_POLL_PERIOD 100 /* ms */ +#define VDPASIM_NOTIFY_DEFVAL 0xffff static struct vdpasim *vdpa_to_sim(struct vdpa_device *vdpa) { @@ -246,6 +254,28 @@ static const struct dma_map_ops vdpasim_dma_ops = { static const struct vdpa_config_ops vdpasim_config_ops; static const struct vdpa_config_ops vdpasim_batch_config_ops; +static void vdpasim_notify_work(struct work_struct *work) +{ + struct vdpasim *vdpasim; + u16 *val; + + vdpasim = container_of(work, struct vdpasim, notify_work.work); + + if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK)) + goto out; + + if (!vdpasim->running) + goto out; + + val = (u16 *)vdpasim->notify; + if (xchg(val, VDPASIM_NOTIFY_DEFVAL) != VDPASIM_NOTIFY_DEFVAL) + schedule_work(&vdpasim->work); + +out: + schedule_delayed_work(&vdpasim->notify_work, + msecs_to_jiffies(VDPASIM_VRING_POLL_PERIOD)); +} + struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr, const struct vdpa_dev_set_config *config) { @@ -287,6 +317,18 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr, set_dma_ops(dev, &vdpasim_dma_ops); vdpasim->vdpa.mdev = dev_attr->mgmt_dev; + if (notify_passthrough) { + INIT_DELAYED_WORK(&vdpasim->notify_work, vdpasim_notify_work); + + vdpasim->notify = __get_free_page(GFP_KERNEL | __GFP_ZERO); + if (!vdpasim->notify) + goto err_iommu; +#ifdef CONFIG_X86 + set_memory_uc(vdpasim->notify, 1); +#endif + *(u16 *)vdpasim->notify = VDPASIM_NOTIFY_DEFVAL; + } + vdpasim->config = kzalloc(dev_attr->config_size, GFP_KERNEL); if (!vdpasim->config) goto err_iommu; @@ -495,6 +537,18 @@ static u8 vdpasim_get_status(struct vdpa_device *vdpa) return status; } +static void vdpasim_set_notify_work(struct vdpasim *vdpasim, bool start) +{ + if (!notify_passthrough) + return; + + if (start) + schedule_delayed_work(&vdpasim->notify_work, + msecs_to_jiffies(VDPASIM_VRING_POLL_PERIOD)); + else + cancel_delayed_work_sync(&vdpasim->notify_work); +} + static void vdpasim_set_status(struct vdpa_device *vdpa, u8 status) { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); @@ -502,12 +556,14 @@ static void vdpasim_set_status(struct vdpa_device *vdpa, u8 status) spin_lock(&vdpasim->lock); vdpasim->status = status; spin_unlock(&vdpasim->lock); + vdpasim_set_notify_work(vdpasim, status & VIRTIO_CONFIG_S_DRIVER_OK); } static int vdpasim_reset(struct vdpa_device *vdpa, bool clear) { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); + vdpasim_set_notify_work(vdpasim, false); spin_lock(&vdpasim->lock); vdpasim->status = 0; vdpasim_do_reset(vdpasim); @@ -672,11 +728,24 @@ static int vdpasim_dma_unmap(struct vdpa_device *vdpa, unsigned int asid, return 0; } +static struct vdpa_notification_area +vdpasim_get_vq_notification(struct vdpa_device *vdpa, u16 qid) +{ + struct vdpasim *vdpasim = vdpa_to_sim(vdpa); + struct vdpa_notification_area notify; + + notify.addr = virt_to_phys((void *)vdpasim->notify); + notify.size = PAGE_SIZE; + + return notify; +} + static void vdpasim_free(struct vdpa_device *vdpa) { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); int i; + vdpasim_set_notify_work(vdpasim, false); cancel_work_sync(&vdpasim->work); for (i = 0; i < vdpasim->dev_attr.nvqs; i++) { @@ -693,6 +762,12 @@ static void vdpasim_free(struct vdpa_device *vdpa) vhost_iotlb_free(vdpasim->iommu); kfree(vdpasim->vqs); kfree(vdpasim->config); + if (vdpasim->notify) { +#ifdef CONFIG_X86 + set_memory_wb(vdpasim->notify, 1); +#endif + free_page(vdpasim->notify); + } } static const struct vdpa_config_ops vdpasim_config_ops = { @@ -704,6 +779,7 @@ static const struct vdpa_config_ops vdpasim_config_ops = { .get_vq_ready = vdpasim_get_vq_ready, .set_vq_state = vdpasim_set_vq_state, .get_vq_state = vdpasim_get_vq_state, + .get_vq_notification = vdpasim_get_vq_notification, .get_vq_align = vdpasim_get_vq_align, .get_vq_group = vdpasim_get_vq_group, .get_device_features = vdpasim_get_device_features, @@ -737,6 +813,7 @@ static const struct vdpa_config_ops vdpasim_batch_config_ops = { .get_vq_ready = vdpasim_get_vq_ready, .set_vq_state = vdpasim_set_vq_state, .get_vq_state = vdpasim_get_vq_state, + .get_vq_notification = vdpasim_get_vq_notification, .get_vq_align = vdpasim_get_vq_align, .get_vq_group = vdpasim_get_vq_group, .get_device_features = vdpasim_get_device_features, diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h index 0e78737dcc16..0769ccbd3911 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.h +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h @@ -69,6 +69,9 @@ struct vdpasim { bool running; /* spinlock to synchronize iommu table */ spinlock_t iommu_lock; + /* dummy notify page */ + unsigned long notify; + struct delayed_work notify_work; }; struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *attr, -- 2.23.0