From patchwork Tue Jan 19 04:59:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 366741 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3526DC433DB for ; Tue, 19 Jan 2021 08:40:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA4A623121 for ; Tue, 19 Jan 2021 08:40:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726798AbhASFWU (ORCPT ); Tue, 19 Jan 2021 00:22:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44154 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726902AbhASFFT (ORCPT ); Tue, 19 Jan 2021 00:05:19 -0500 Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C0CAC061757 for ; Mon, 18 Jan 2021 21:04:38 -0800 (PST) Received: by mail-pf1-x42b.google.com with SMTP id w18so228900pfu.9 for ; Mon, 18 Jan 2021 21:04:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=hq6cLGhX+YOdloZCBCv76n2UjaYC8NZfkFs6/p+ZtOg=; b=W8y876Dbq8gZuEg5QYXKhKTizoMMwtFxcmKeIZtDQdx+XEt3dW/eHtSMhQvknQYW4K DnsCpn+GirhCRLFyk/uVDaIJoXZgyWsH6gU53zdrGPud9lsener1pfIQEwdiCZRktfE+ Ne1ZR7dli2HUDcE+3V2rbyvftav5V4WgBCwhpQ0bHoynV0GboyaGO/cjnRSZdzh0GmFw r/A5ZX/PxqxanTpbUqh+VaClMqoh4p4eePPZY6MRWFJ7BiyHJsTxQWwUiwGliuSOKvLc PCreg4kS3gTI+lm3d0KE5HrHAWJ4B0/fMhjVOWrn+u+7Kwg0P9wxlbpTSDhJDbdRaU+G Y9Jg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=hq6cLGhX+YOdloZCBCv76n2UjaYC8NZfkFs6/p+ZtOg=; b=pjLbHlIqF9K+ivhswjPY+SGjfra4sSsqKGhEGJCfANM8eQUCh/gECAqic4xG2klpoX JrlWmjnNLOqHI+FsEFE44binm4NparNo5vLhMkdK0WENJfX0q2ZXE9Tw3QDWiiF6E69O 06xqFSrDMEE78JdUeUIvfEm2v7NO+9vp7qqM1U7qLmUMKUR79q2pPdzUsk1prFvcX6uc cL3V7K/4iri6QxEenp0sKuYF+30i1UWEYErZkJSUheU8st4TiuuOV6zrUnIINv1+zJ3a o9XQN4jpdipx6rcqIdmcyM2R8zIikG2ye/Ab7Nn5d51dOKJwIAmk1COXAXEj/SKVBUlq jkZg== X-Gm-Message-State: AOAM533SPfOq1QpFfDt48YUko5VGu1c9zIoaN/aPZGQiOZwf5ZgzhEXj R80NvvgdzpjbGidelFF5xhYN X-Google-Smtp-Source: ABdhPJwhMmXGRAF9exzwdYFbs4DDh7HaNjaSgRVmLvyUt1TO1CzzbUW14r26LDKrseM7tbJ/BRrzFA== X-Received: by 2002:a62:ddcd:0:b029:1a6:99ff:a75e with SMTP id w196-20020a62ddcd0000b02901a699ffa75emr2486197pff.42.1611032678076; Mon, 18 Jan 2021 21:04:38 -0800 (PST) Received: from localhost ([139.177.225.243]) by smtp.gmail.com with ESMTPSA id gv22sm1047509pjb.56.2021.01.18.21.04.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jan 2021 21:04:37 -0800 (PST) From: Xie Yongji To: mst@redhat.com, jasowang@redhat.com, stefanha@redhat.com, sgarzare@redhat.com, parav@nvidia.com, bob.liu@oracle.com, hch@infradead.org, rdunlap@infradead.org, willy@infradead.org, viro@zeniv.linux.org.uk, axboe@kernel.dk, bcrl@kvack.org, corbet@lwn.net Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org Subject: [RFC v3 01/11] eventfd: track eventfd_signal() recursion depth separately in different cases Date: Tue, 19 Jan 2021 12:59:10 +0800 Message-Id: <20210119045920.447-2-xieyongji@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210119045920.447-1-xieyongji@bytedance.com> References: <20210119045920.447-1-xieyongji@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Now we have a global percpu counter to limit the recursion depth of eventfd_signal(). This can avoid deadlock or stack overflow. But in stack overflow case, it should be OK to increase the recursion depth if needed. So we add a percpu counter in eventfd_ctx to limit the recursion depth for deadlock case. Then it could be fine to increase the global percpu counter later. Signed-off-by: Xie Yongji --- fs/aio.c | 3 ++- fs/eventfd.c | 20 +++++++++++++++++++- include/linux/eventfd.h | 5 +---- 3 files changed, 22 insertions(+), 6 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index 1f32da13d39e..5d82903161f5 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1698,7 +1698,8 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, list_del(&iocb->ki_list); iocb->ki_res.res = mangle_poll(mask); req->done = true; - if (iocb->ki_eventfd && eventfd_signal_count()) { + if (iocb->ki_eventfd && + eventfd_signal_count(iocb->ki_eventfd)) { iocb = NULL; INIT_WORK(&req->work, aio_poll_put_work); schedule_work(&req->work); diff --git a/fs/eventfd.c b/fs/eventfd.c index e265b6dd4f34..2df24f9bada3 100644 --- a/fs/eventfd.c +++ b/fs/eventfd.c @@ -25,6 +25,8 @@ #include #include +#define EVENTFD_WAKE_DEPTH 0 + DEFINE_PER_CPU(int, eventfd_wake_count); static DEFINE_IDA(eventfd_ida); @@ -42,9 +44,17 @@ struct eventfd_ctx { */ __u64 count; unsigned int flags; + int __percpu *wake_count; int id; }; +bool eventfd_signal_count(struct eventfd_ctx *ctx) +{ + return (this_cpu_read(*ctx->wake_count) || + this_cpu_read(eventfd_wake_count) > EVENTFD_WAKE_DEPTH); +} +EXPORT_SYMBOL_GPL(eventfd_signal_count); + /** * eventfd_signal - Adds @n to the eventfd counter. * @ctx: [in] Pointer to the eventfd context. @@ -71,17 +81,19 @@ __u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n) * it returns true, the eventfd_signal() call should be deferred to a * safe context. */ - if (WARN_ON_ONCE(this_cpu_read(eventfd_wake_count))) + if (WARN_ON_ONCE(eventfd_signal_count(ctx))) return 0; spin_lock_irqsave(&ctx->wqh.lock, flags); this_cpu_inc(eventfd_wake_count); + this_cpu_inc(*ctx->wake_count); if (ULLONG_MAX - ctx->count < n) n = ULLONG_MAX - ctx->count; ctx->count += n; if (waitqueue_active(&ctx->wqh)) wake_up_locked_poll(&ctx->wqh, EPOLLIN); this_cpu_dec(eventfd_wake_count); + this_cpu_dec(*ctx->wake_count); spin_unlock_irqrestore(&ctx->wqh.lock, flags); return n; @@ -92,6 +104,7 @@ static void eventfd_free_ctx(struct eventfd_ctx *ctx) { if (ctx->id >= 0) ida_simple_remove(&eventfd_ida, ctx->id); + free_percpu(ctx->wake_count); kfree(ctx); } @@ -423,6 +436,11 @@ static int do_eventfd(unsigned int count, int flags) kref_init(&ctx->kref); init_waitqueue_head(&ctx->wqh); + ctx->wake_count = alloc_percpu(int); + if (!ctx->wake_count) { + kfree(ctx); + return -ENOMEM; + } ctx->count = count; ctx->flags = flags; ctx->id = ida_simple_get(&eventfd_ida, 0, 0, GFP_KERNEL); diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h index fa0a524baed0..1a11ebbd74a9 100644 --- a/include/linux/eventfd.h +++ b/include/linux/eventfd.h @@ -45,10 +45,7 @@ void eventfd_ctx_do_read(struct eventfd_ctx *ctx, __u64 *cnt); DECLARE_PER_CPU(int, eventfd_wake_count); -static inline bool eventfd_signal_count(void) -{ - return this_cpu_read(eventfd_wake_count); -} +bool eventfd_signal_count(struct eventfd_ctx *ctx); #else /* CONFIG_EVENTFD */ From patchwork Tue Jan 19 04:59:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 366749 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0781C433E0 for ; Tue, 19 Jan 2021 05:24:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9C6A222DFB for ; Tue, 19 Jan 2021 05:24:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389139AbhASFYG (ORCPT ); Tue, 19 Jan 2021 00:24:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389390AbhASFG5 (ORCPT ); Tue, 19 Jan 2021 00:06:57 -0500 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52BC3C061799 for ; Mon, 18 Jan 2021 21:04:53 -0800 (PST) Received: by mail-pf1-x42a.google.com with SMTP id y205so5690751pfc.5 for ; Mon, 18 Jan 2021 21:04:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=U0120iNFu1UQ+XQP2804t9yWUT9nyzP1s7JWVirZ0CQ=; b=tT/tmNAi6NU57xmHjfGmqHgX95hCN5stlPBS4x34MDgSRzGJgUPlWjosZg+6PyfxjO IlCL7iHuRliYzhRIUJwqVTWRZl33hJvmOwmriMEbSe8wcZxoyWzpiSsyMJjN59tnB6yK PPMsjJIyNWtdFwH4fXQAEjDjWjDvv/QoSFx+BpJjhKLG5bk2eHnhh3/IMNIoj7J3zH/U kQegq2euiTFuF9uqisspaevugD1zMGgphJ3VAW+xVbApOGXlsUBgHcU+0uBphjIjnbvF 99auMuVMqsaT7A8eptrh9JDdjA7uJnYlGEhuScmBxfPlLzwx4zdrr4WesSpAulQibsru 5Lcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=U0120iNFu1UQ+XQP2804t9yWUT9nyzP1s7JWVirZ0CQ=; b=Pgh4VRR6As0z1L0l7t5Umn3r8PJVVF+OUHlVxZtA2sM0cKv+SNRjz4YB76A7iITKSW bdNsAgo1wdd4U2m1VhsOw4G66Bsfl0mYA0pineNlo9YLJ+OjY/99uGNpO0gHLX2dBcFc wHpwoxs6sjs1xiFIdMEIu0B/sQkZvTCRodMySkW0H4zqloE/f6rqhzdVCaSnPgU5+Ua9 F4WEuuzAxVhD0T5LZabFiAz7CLSk47L2pXghGT7p2dRnjBtlDsQbJJu/cqnIuI05/YNL 1vuPb1BLU8u9b+VmpRkhiYNGBPSWAKmoAuAyIypYOIcnQglLZE/fCTpyQYv+QsC0M9sX 2jeg== X-Gm-Message-State: AOAM533HavGTU2CJc+tcjNpEqjzYkqVziMrpItLL23x/Tgz2Xw9RYPXM PsArZCt80x6Bm0G+sUNt85iV X-Google-Smtp-Source: ABdhPJz29+5qkk0tFpBdHE1YKxTcsaEJOC9RJCsgQpfbCkBSRwz57KBR46or6uBk7ojXObygUicQrg== X-Received: by 2002:a63:d601:: with SMTP id q1mr2833194pgg.417.1611032692863; Mon, 18 Jan 2021 21:04:52 -0800 (PST) Received: from localhost ([139.177.225.243]) by smtp.gmail.com with ESMTPSA id ob6sm1047360pjb.30.2021.01.18.21.04.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jan 2021 21:04:52 -0800 (PST) From: Xie Yongji To: mst@redhat.com, jasowang@redhat.com, stefanha@redhat.com, sgarzare@redhat.com, parav@nvidia.com, bob.liu@oracle.com, hch@infradead.org, rdunlap@infradead.org, willy@infradead.org, viro@zeniv.linux.org.uk, axboe@kernel.dk, bcrl@kvack.org, corbet@lwn.net Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org Subject: [RFC v3 05/11] vdpa: shared virtual addressing support Date: Tue, 19 Jan 2021 12:59:14 +0800 Message-Id: <20210119045920.447-6-xieyongji@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210119045920.447-1-xieyongji@bytedance.com> References: <20210119045920.447-1-xieyongji@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patches introduces SVA (Shared Virtual Addressing) support for vDPA device. During vDPA device allocation, vDPA device driver needs to indicate whether SVA is supported by the device. Then vhost-vdpa bus driver will not pin user page and transfer userspace virtual address instead of physical address during DMA mapping. Suggested-by: Jason Wang Signed-off-by: Xie Yongji --- drivers/vdpa/ifcvf/ifcvf_main.c | 2 +- drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- drivers/vdpa/vdpa.c | 5 ++++- drivers/vdpa/vdpa_sim/vdpa_sim.c | 3 ++- drivers/vhost/vdpa.c | 35 +++++++++++++++++++++++------------ include/linux/vdpa.h | 10 +++++++--- 6 files changed, 38 insertions(+), 19 deletions(-) diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c index 23474af7da40..95c4601f82f5 100644 --- a/drivers/vdpa/ifcvf/ifcvf_main.c +++ b/drivers/vdpa/ifcvf/ifcvf_main.c @@ -439,7 +439,7 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id) adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa, dev, &ifc_vdpa_ops, - IFCVF_MAX_QUEUE_PAIRS * 2, NULL); + IFCVF_MAX_QUEUE_PAIRS * 2, NULL, false); if (adapter == NULL) { IFCVF_ERR(pdev, "Failed to allocate vDPA structure"); return -ENOMEM; diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c index 77595c81488d..05988d6907f2 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c @@ -1959,7 +1959,7 @@ static int mlx5v_probe(struct auxiliary_device *adev, max_vqs = min_t(u32, max_vqs, MLX5_MAX_SUPPORTED_VQS); ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops, - 2 * mlx5_vdpa_max_qps(max_vqs), NULL); + 2 * mlx5_vdpa_max_qps(max_vqs), NULL, false); if (IS_ERR(ndev)) return PTR_ERR(ndev); diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c index 32bd48baffab..50cab930b2e5 100644 --- a/drivers/vdpa/vdpa.c +++ b/drivers/vdpa/vdpa.c @@ -72,6 +72,7 @@ static void vdpa_release_dev(struct device *d) * @nvqs: number of virtqueues supported by this device * @size: size of the parent structure that contains private data * @name: name of the vdpa device; optional. + * @sva: indicate whether SVA (Shared Virtual Addressing) is supported * * Driver should use vdpa_alloc_device() wrapper macro instead of * using this directly. @@ -81,7 +82,8 @@ static void vdpa_release_dev(struct device *d) */ struct vdpa_device *__vdpa_alloc_device(struct device *parent, const struct vdpa_config_ops *config, - int nvqs, size_t size, const char *name) + int nvqs, size_t size, const char *name, + bool sva) { struct vdpa_device *vdev; int err = -EINVAL; @@ -108,6 +110,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent, vdev->config = config; vdev->features_valid = false; vdev->nvqs = nvqs; + vdev->sva = sva; if (name) err = dev_set_name(&vdev->dev, "%s", name); diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c index 85776e4e6749..03c796873a6b 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -367,7 +367,8 @@ static struct vdpasim *vdpasim_create(const char *name) else ops = &vdpasim_net_config_ops; - vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops, VDPASIM_VQ_NUM, name); + vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops, + VDPASIM_VQ_NUM, name, false); if (!vdpasim) goto err_alloc; diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index 4a241d380c40..36b6950ba37f 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -486,21 +486,25 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last) { struct vhost_dev *dev = &v->vdev; + struct vdpa_device *vdpa = v->vdpa; struct vhost_iotlb *iotlb = dev->iotlb; struct vhost_iotlb_map *map; struct page *page; unsigned long pfn, pinned; while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) { - pinned = map->size >> PAGE_SHIFT; - for (pfn = map->addr >> PAGE_SHIFT; - pinned > 0; pfn++, pinned--) { - page = pfn_to_page(pfn); - if (map->perm & VHOST_ACCESS_WO) - set_page_dirty_lock(page); - unpin_user_page(page); + if (!vdpa->sva) { + pinned = map->size >> PAGE_SHIFT; + for (pfn = map->addr >> PAGE_SHIFT; + pinned > 0; pfn++, pinned--) { + page = pfn_to_page(pfn); + if (map->perm & VHOST_ACCESS_WO) + set_page_dirty_lock(page); + unpin_user_page(page); + } + atomic64_sub(map->size >> PAGE_SHIFT, + &dev->mm->pinned_vm); } - atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm); vhost_iotlb_map_free(iotlb, map); } } @@ -558,13 +562,15 @@ static int vhost_vdpa_map(struct vhost_vdpa *v, r = iommu_map(v->domain, iova, pa, size, perm_to_iommu_flags(perm)); } - - if (r) + if (r) { vhost_iotlb_del_range(dev->iotlb, iova, iova + size - 1); - else + return r; + } + + if (!vdpa->sva) atomic64_add(size >> PAGE_SHIFT, &dev->mm->pinned_vm); - return r; + return 0; } static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size) @@ -589,6 +595,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, struct vhost_iotlb_msg *msg) { struct vhost_dev *dev = &v->vdev; + struct vdpa_device *vdpa = v->vdpa; struct vhost_iotlb *iotlb = dev->iotlb; struct page **page_list; unsigned long list_size = PAGE_SIZE / sizeof(struct page *); @@ -607,6 +614,10 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, msg->iova + msg->size - 1)) return -EEXIST; + if (vdpa->sva) + return vhost_vdpa_map(v, msg->iova, msg->size, + msg->uaddr, msg->perm); + /* Limit the use of memory for bookkeeping */ page_list = (struct page **) __get_free_page(GFP_KERNEL); if (!page_list) diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h index cb5a3d847af3..f86869651614 100644 --- a/include/linux/vdpa.h +++ b/include/linux/vdpa.h @@ -44,6 +44,7 @@ struct vdpa_parent_dev; * @config: the configuration ops for this device. * @index: device index * @features_valid: were features initialized? for legacy guests + * @sva: indicate whether SVA (Shared Virtual Addressing) is supported * @nvqs: maximum number of supported virtqueues * @pdev: parent device pointer; caller must setup when registering device as part * of dev_add() parentdev ops callback before invoking _vdpa_register_device(). @@ -54,6 +55,7 @@ struct vdpa_device { const struct vdpa_config_ops *config; unsigned int index; bool features_valid; + bool sva; int nvqs; struct vdpa_parent_dev *pdev; }; @@ -250,14 +252,16 @@ struct vdpa_config_ops { struct vdpa_device *__vdpa_alloc_device(struct device *parent, const struct vdpa_config_ops *config, - int nvqs, size_t size, const char *name); + int nvqs, size_t size, + const char *name, bool sva); -#define vdpa_alloc_device(dev_struct, member, parent, config, nvqs, name) \ +#define vdpa_alloc_device(dev_struct, member, parent, config, \ + nvqs, name, sva) \ container_of(__vdpa_alloc_device( \ parent, config, nvqs, \ sizeof(dev_struct) + \ BUILD_BUG_ON_ZERO(offsetof( \ - dev_struct, member)), name), \ + dev_struct, member)), name, sva), \ dev_struct, member) int vdpa_register_device(struct vdpa_device *vdev); From patchwork Tue Jan 19 05:07:53 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 366743 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6CD7AC433E0 for ; Tue, 19 Jan 2021 08:17:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EF07B2311C for ; Tue, 19 Jan 2021 08:17:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389779AbhASFZ1 (ORCPT ); Tue, 19 Jan 2021 00:25:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727272AbhASFJH (ORCPT ); Tue, 19 Jan 2021 00:09:07 -0500 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7E56C0613C1 for ; Mon, 18 Jan 2021 21:08:21 -0800 (PST) Received: by mail-pg1-x535.google.com with SMTP id i7so12290052pgc.8 for ; Mon, 18 Jan 2021 21:08:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=X3RPlMFEPCGJ4YEaPIHbmxjgX2R+e2jG8nVJe1O91Ko=; b=xMayhPyLCGGp3uWxmdCS/QBjfbB86PV5GUw4nC7GKwyLa9QKIgQDSLN2DCRVg0uaQL Lq/uCIrJOi4ITHNf90tr0c2AKjIm+jHBghnPyf3IbjFxXVWktPNTa6eP85rlnXvt7zYf 8LspAr8jmwp74QKHRfAELSHDoCYYk2qMC0QOYTlTm2o5rObTXCJqc2LKtSdZPey+L02F u79xeKR//NrKyf8RFAN/h/iNiOrqxRACvUZFY/60Sg2S+JOFiRqHq8Sr0+8oi5UoLNNA 3FDHPO4VOZ69P4VkPLT/Sjeh0Z0lvM0ii4hHqBIYi7AARhVyqp15mLGACsthA+ofNtGQ nzxQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=X3RPlMFEPCGJ4YEaPIHbmxjgX2R+e2jG8nVJe1O91Ko=; b=UbIJv97HWVvYxxrhoJolRfeU/4aWpcSDS9SDaZmo6pwb6rPI+4ts5sJpYTVq3cUwx1 u8pUyWJvWjeozORhMXEr6XCkBKZpKaHj8W61jE4/7mjvnF7F4c4zW2vl4K1ZyuaebprR fXPahVm/cw9zhoM0jZHI57oDMtd0mjaTljiutSNzB0aMGAZ1MA9xjGvTDensuXjpMBVU 0vvYn0tryGA064UhElO8GdZGZT705gTLcLtytdgNchO1nD8Hhgvjmx0bU7s7jtrhKHpO c+bz37tcy2pGzTujIeoOWdi+v1uZ8VAoxUR1wBGBD7ofMI2AMznzGM9DfJG0juCHAe10 ZqKg== X-Gm-Message-State: AOAM531lyLC66eGq4ZPs2cDAz+2gd5fRin9x6SitS18ih1q/5s8uyI3M kNF3iqUZ7U9RUW2GQidVkVl+ X-Google-Smtp-Source: ABdhPJwgiEvqMUDb8p/SlDvdrPbGREy3CLngIuLcB2KRSohppgSWX/PrCq5qTgBlN71lbJBdKoXLXg== X-Received: by 2002:a62:844b:0:b029:19e:62a0:ca18 with SMTP id k72-20020a62844b0000b029019e62a0ca18mr2782394pfd.46.1611032900857; Mon, 18 Jan 2021 21:08:20 -0800 (PST) Received: from localhost ([139.177.225.243]) by smtp.gmail.com with ESMTPSA id o14sm17958539pgr.44.2021.01.18.21.08.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jan 2021 21:08:20 -0800 (PST) From: Xie Yongji To: mst@redhat.com, jasowang@redhat.com, stefanha@redhat.com, sgarzare@redhat.com, parav@nvidia.com, bob.liu@oracle.com, hch@infradead.org, rdunlap@infradead.org, willy@infradead.org, viro@zeniv.linux.org.uk, axboe@kernel.dk, bcrl@kvack.org, corbet@lwn.net Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org Subject: [RFC v3 08/11] vduse: Introduce VDUSE - vDPA Device in Userspace Date: Tue, 19 Jan 2021 13:07:53 +0800 Message-Id: <20210119050756.600-2-xieyongji@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210119050756.600-1-xieyongji@bytedance.com> References: <20210119045920.447-1-xieyongji@bytedance.com> <20210119050756.600-1-xieyongji@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This VDUSE driver enables implementing vDPA devices in userspace. Both control path and data path of vDPA devices will be able to be handled in userspace. In the control path, the VDUSE driver will make use of message mechnism to forward the config operation from vdpa bus driver to userspace. Userspace can use read()/write() to receive/reply those control messages. In the data path, VDUSE_IOTLB_GET_FD ioctl will be used to get the file descriptors referring to vDPA device's iova regions. Then userspace can use mmap() to access those iova regions. Besides, the eventfd mechanism is used to trigger interrupt callbacks and receive virtqueue kicks in userspace. Signed-off-by: Xie Yongji --- Documentation/driver-api/vduse.rst | 85 ++ Documentation/userspace-api/ioctl/ioctl-number.rst | 1 + drivers/vdpa/Kconfig | 7 + drivers/vdpa/Makefile | 1 + drivers/vdpa/vdpa_user/Makefile | 5 + drivers/vdpa/vdpa_user/eventfd.c | 221 ++++ drivers/vdpa/vdpa_user/eventfd.h | 48 + drivers/vdpa/vdpa_user/iova_domain.c | 426 +++++++ drivers/vdpa/vdpa_user/iova_domain.h | 68 ++ drivers/vdpa/vdpa_user/vduse.h | 62 + drivers/vdpa/vdpa_user/vduse_dev.c | 1217 ++++++++++++++++++++ include/uapi/linux/vdpa.h | 1 + include/uapi/linux/vduse.h | 125 ++ 13 files changed, 2267 insertions(+) create mode 100644 Documentation/driver-api/vduse.rst create mode 100644 drivers/vdpa/vdpa_user/Makefile create mode 100644 drivers/vdpa/vdpa_user/eventfd.c create mode 100644 drivers/vdpa/vdpa_user/eventfd.h create mode 100644 drivers/vdpa/vdpa_user/iova_domain.c create mode 100644 drivers/vdpa/vdpa_user/iova_domain.h create mode 100644 drivers/vdpa/vdpa_user/vduse.h create mode 100644 drivers/vdpa/vdpa_user/vduse_dev.c create mode 100644 include/uapi/linux/vduse.h diff --git a/Documentation/driver-api/vduse.rst b/Documentation/driver-api/vduse.rst new file mode 100644 index 000000000000..9418a7f6646b --- /dev/null +++ b/Documentation/driver-api/vduse.rst @@ -0,0 +1,85 @@ +================================== +VDUSE - "vDPA Device in Userspace" +================================== + +vDPA (virtio data path acceleration) device is a device that uses a +datapath which complies with the virtio specifications with vendor +specific control path. vDPA devices can be both physically located on +the hardware or emulated by software. VDUSE is a framework that makes it +possible to implement software-emulated vDPA devices in userspace. + +How VDUSE works +------------ +Each userspace vDPA device is created by the VDUSE_CREATE_DEV ioctl on +the VDUSE character device (/dev/vduse). Then a file descriptor pointing +to the new resources will be returned, which can be used to implement the +userspace vDPA device's control path and data path. + +To implement control path, the read/write operations to the file descriptor +will be used to receive/reply the control messages from/to VDUSE driver. +Those control messages are mostly based on the vdpa_config_ops which defines +a unified interface to control different types of vDPA device. + +The following types of messages are provided by the VDUSE framework now: + +- VDUSE_SET_VQ_ADDR: Set the addresses of the different aspects of virtqueue. + +- VDUSE_SET_VQ_NUM: Set the size of virtqueue + +- VDUSE_SET_VQ_READY: Set ready status of virtqueue + +- VDUSE_GET_VQ_READY: Get ready status of virtqueue + +- VDUSE_SET_VQ_STATE: Set the state (last_avail_idx) for virtqueue + +- VDUSE_GET_VQ_STATE: Get the state (last_avail_idx) for virtqueue + +- VDUSE_SET_FEATURES: Set virtio features supported by the driver + +- VDUSE_GET_FEATURES: Get virtio features supported by the device + +- VDUSE_SET_STATUS: Set the device status + +- VDUSE_GET_STATUS: Get the device status + +- VDUSE_SET_CONFIG: Write to device specific configuration space + +- VDUSE_GET_CONFIG: Read from device specific configuration space + +- VDUSE_UPDATE_IOTLB: Notify userspace to update the memory mapping in device IOTLB + +Please see include/linux/vdpa.h for details. + +In the data path, vDPA device's iova regions will be mapped into userspace with +the help of VDUSE_IOTLB_GET_FD ioctl on the userspace vDPA device fd: + +- VDUSE_IOTLB_GET_FD: get the file descriptor to iova region. Userspace can + access this iova region by passing the fd to mmap(2). + +Besides, the eventfd mechanism is used to trigger interrupt callbacks and +receive virtqueue kicks in userspace. The following ioctls on the userspace +vDPA device fd are provided to support that: + +- VDUSE_VQ_SETUP_KICKFD: set the kickfd for virtqueue, this eventfd is used + by VDUSE driver to notify userspace to consume the vring. + +- VDUSE_VQ_SETUP_IRQFD: set the irqfd for virtqueue, this eventfd is used + by userspace to notify VDUSE driver to trigger interrupt callbacks. + +MMU-based IOMMU Driver +---------------------- +In virtio-vdpa case, VDUSE framework implements a MMU-based on-chip IOMMU +driver to support mapping the kernel dma buffer into the userspace iova +region dynamically. + +The basic idea behind this driver is treating MMU (VA->PA) as IOMMU (IOVA->PA). +The driver will set up MMU mapping instead of IOMMU mapping for the DMA transfer +so that the userspace process is able to use its virtual address to access +the dma buffer in kernel. + +And to avoid security issue, a bounce-buffering mechanism is introduced to +prevent userspace accessing the original buffer directly which may contain other +kernel data. During the mapping, unmapping, the driver will copy the data from +the original buffer to the bounce buffer and back, depending on the direction of +the transfer. And the bounce-buffer addresses will be mapped into the user address +space instead of the original one. diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst index a4c75a28c839..71722e6f8f23 100644 --- a/Documentation/userspace-api/ioctl/ioctl-number.rst +++ b/Documentation/userspace-api/ioctl/ioctl-number.rst @@ -300,6 +300,7 @@ Code Seq# Include File Comments 'z' 10-4F drivers/s390/crypto/zcrypt_api.h conflict! '|' 00-7F linux/media.h 0x80 00-1F linux/fb.h +0x81 00-1F linux/vduse.h 0x89 00-06 arch/x86/include/asm/sockios.h 0x89 0B-DF linux/sockios.h 0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig index 4be7be39be26..667354309bf4 100644 --- a/drivers/vdpa/Kconfig +++ b/drivers/vdpa/Kconfig @@ -21,6 +21,13 @@ config VDPA_SIM to RX. This device is used for testing, prototyping and development of vDPA. +config VDPA_USER + tristate "VDUSE (vDPA Device in Userspace) support" + depends on EVENTFD && MMU && HAS_DMA + help + With VDUSE it is possible to emulate a vDPA Device + in a userspace program. + config IFCVF tristate "Intel IFC VF vDPA driver" depends on PCI_MSI diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile index d160e9b63a66..66e97778ad03 100644 --- a/drivers/vdpa/Makefile +++ b/drivers/vdpa/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_VDPA) += vdpa.o obj-$(CONFIG_VDPA_SIM) += vdpa_sim/ +obj-$(CONFIG_VDPA_USER) += vdpa_user/ obj-$(CONFIG_IFCVF) += ifcvf/ obj-$(CONFIG_MLX5_VDPA) += mlx5/ diff --git a/drivers/vdpa/vdpa_user/Makefile b/drivers/vdpa/vdpa_user/Makefile new file mode 100644 index 000000000000..b7645e36992b --- /dev/null +++ b/drivers/vdpa/vdpa_user/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 + +vduse-y := vduse_dev.o iova_domain.o eventfd.o + +obj-$(CONFIG_VDPA_USER) += vduse.o diff --git a/drivers/vdpa/vdpa_user/eventfd.c b/drivers/vdpa/vdpa_user/eventfd.c new file mode 100644 index 000000000000..dbffddb08908 --- /dev/null +++ b/drivers/vdpa/vdpa_user/eventfd.c @@ -0,0 +1,221 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Eventfd support for VDUSE + * + * Copyright (C) 2020 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji + * + */ + +#include +#include +#include +#include +#include +#include + +#include "eventfd.h" + +static struct workqueue_struct *vduse_irqfd_cleanup_wq; + +static void vduse_virqfd_shutdown(struct work_struct *work) +{ + u64 cnt; + struct vduse_virqfd *virqfd = container_of(work, + struct vduse_virqfd, shutdown); + + eventfd_ctx_remove_wait_queue(virqfd->ctx, &virqfd->wait, &cnt); + flush_work(&virqfd->inject); + eventfd_ctx_put(virqfd->ctx); + kfree(virqfd); +} + +static void vduse_virqfd_inject(struct work_struct *work) +{ + struct vduse_virqfd *virqfd = container_of(work, + struct vduse_virqfd, inject); + struct vduse_virtqueue *vq = virqfd->vq; + + spin_lock_irq(&vq->irq_lock); + if (vq->ready && vq->cb) + vq->cb(vq->private); + spin_unlock_irq(&vq->irq_lock); +} + +static void virqfd_deactivate(struct vduse_virqfd *virqfd) +{ + queue_work(vduse_irqfd_cleanup_wq, &virqfd->shutdown); +} + +static int vduse_virqfd_wakeup(wait_queue_entry_t *wait, unsigned int mode, + int sync, void *key) +{ + struct vduse_virqfd *virqfd = container_of(wait, struct vduse_virqfd, wait); + struct vduse_virtqueue *vq = virqfd->vq; + + __poll_t flags = key_to_poll(key); + + if (flags & EPOLLIN) + schedule_work(&virqfd->inject); + + if (flags & EPOLLHUP) { + spin_lock(&vq->irq_lock); + if (vq->virqfd == virqfd) { + vq->virqfd = NULL; + virqfd_deactivate(virqfd); + } + spin_unlock(&vq->irq_lock); + } + + return 0; +} + +static void vduse_virqfd_ptable_queue_proc(struct file *file, + wait_queue_head_t *wqh, poll_table *pt) +{ + struct vduse_virqfd *virqfd = container_of(pt, struct vduse_virqfd, pt); + + add_wait_queue(wqh, &virqfd->wait); +} + +int vduse_virqfd_setup(struct vduse_dev *dev, + struct vduse_vq_eventfd *eventfd) +{ + struct vduse_virqfd *virqfd; + struct fd irqfd; + struct eventfd_ctx *ctx; + struct vduse_virtqueue *vq; + __poll_t events; + int ret; + + if (eventfd->index >= dev->vq_num) + return -EINVAL; + + vq = &dev->vqs[eventfd->index]; + virqfd = kzalloc(sizeof(*virqfd), GFP_KERNEL); + if (!virqfd) + return -ENOMEM; + + INIT_WORK(&virqfd->shutdown, vduse_virqfd_shutdown); + INIT_WORK(&virqfd->inject, vduse_virqfd_inject); + + ret = -EBADF; + irqfd = fdget(eventfd->fd); + if (!irqfd.file) + goto err_fd; + + ctx = eventfd_ctx_fileget(irqfd.file); + if (IS_ERR(ctx)) { + ret = PTR_ERR(ctx); + goto err_ctx; + } + + virqfd->vq = vq; + virqfd->ctx = ctx; + spin_lock(&vq->irq_lock); + if (vq->virqfd) + virqfd_deactivate(virqfd); + vq->virqfd = virqfd; + spin_unlock(&vq->irq_lock); + + init_waitqueue_func_entry(&virqfd->wait, vduse_virqfd_wakeup); + init_poll_funcptr(&virqfd->pt, vduse_virqfd_ptable_queue_proc); + + events = vfs_poll(irqfd.file, &virqfd->pt); + + /* + * Check if there was an event already pending on the eventfd + * before we registered and trigger it as if we didn't miss it. + */ + if (events & EPOLLIN) + schedule_work(&virqfd->inject); + + fdput(irqfd); + + return 0; +err_ctx: + fdput(irqfd); +err_fd: + kfree(virqfd); + return ret; +} + +void vduse_virqfd_release(struct vduse_dev *dev) +{ + int i; + + for (i = 0; i < dev->vq_num; i++) { + struct vduse_virtqueue *vq = &dev->vqs[i]; + + spin_lock(&vq->irq_lock); + if (vq->virqfd) { + virqfd_deactivate(vq->virqfd); + vq->virqfd = NULL; + } + spin_unlock(&vq->irq_lock); + } + flush_workqueue(vduse_irqfd_cleanup_wq); +} + +int vduse_virqfd_init(void) +{ + vduse_irqfd_cleanup_wq = alloc_workqueue("vduse-irqfd-cleanup", + WQ_UNBOUND, 0); + if (!vduse_irqfd_cleanup_wq) + return -ENOMEM; + + return 0; +} + +void vduse_virqfd_exit(void) +{ + destroy_workqueue(vduse_irqfd_cleanup_wq); +} + +void vduse_vq_kick(struct vduse_virtqueue *vq) +{ + spin_lock(&vq->kick_lock); + if (vq->ready && vq->kickfd) + eventfd_signal(vq->kickfd, 1); + spin_unlock(&vq->kick_lock); +} + +int vduse_kickfd_setup(struct vduse_dev *dev, + struct vduse_vq_eventfd *eventfd) +{ + struct eventfd_ctx *ctx; + struct vduse_virtqueue *vq; + + if (eventfd->index >= dev->vq_num) + return -EINVAL; + + vq = &dev->vqs[eventfd->index]; + ctx = eventfd_ctx_fdget(eventfd->fd); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); + + spin_lock(&vq->kick_lock); + if (vq->kickfd) + eventfd_ctx_put(vq->kickfd); + vq->kickfd = ctx; + spin_unlock(&vq->kick_lock); + + return 0; +} + +void vduse_kickfd_release(struct vduse_dev *dev) +{ + int i; + + for (i = 0; i < dev->vq_num; i++) { + struct vduse_virtqueue *vq = &dev->vqs[i]; + + spin_lock(&vq->kick_lock); + if (vq->kickfd) { + eventfd_ctx_put(vq->kickfd); + vq->kickfd = NULL; + } + spin_unlock(&vq->kick_lock); + } +} diff --git a/drivers/vdpa/vdpa_user/eventfd.h b/drivers/vdpa/vdpa_user/eventfd.h new file mode 100644 index 000000000000..14269ff27f47 --- /dev/null +++ b/drivers/vdpa/vdpa_user/eventfd.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Eventfd support for VDUSE + * + * Copyright (C) 2020 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji + * + */ + +#ifndef _VDUSE_EVENTFD_H +#define _VDUSE_EVENTFD_H + +#include +#include +#include +#include + +#include "vduse.h" + +struct vduse_dev; + +struct vduse_virqfd { + struct eventfd_ctx *ctx; + struct vduse_virtqueue *vq; + struct work_struct inject; + struct work_struct shutdown; + wait_queue_entry_t wait; + poll_table pt; +}; + +int vduse_virqfd_setup(struct vduse_dev *dev, + struct vduse_vq_eventfd *eventfd); + +void vduse_virqfd_release(struct vduse_dev *dev); + +int vduse_virqfd_init(void); + +void vduse_virqfd_exit(void); + +void vduse_vq_kick(struct vduse_virtqueue *vq); + +int vduse_kickfd_setup(struct vduse_dev *dev, + struct vduse_vq_eventfd *eventfd); + +void vduse_kickfd_release(struct vduse_dev *dev); + +#endif /* _VDUSE_EVENTFD_H */ diff --git a/drivers/vdpa/vdpa_user/iova_domain.c b/drivers/vdpa/vdpa_user/iova_domain.c new file mode 100644 index 000000000000..cdfef8e9f9d6 --- /dev/null +++ b/drivers/vdpa/vdpa_user/iova_domain.c @@ -0,0 +1,426 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MMU-based IOMMU implementation + * + * Copyright (C) 2020 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji + * + */ + +#include +#include +#include + +#include "iova_domain.h" + +#define IOVA_START_PFN 1 +#define IOVA_ALLOC_ORDER 12 +#define IOVA_ALLOC_SIZE (1 << IOVA_ALLOC_ORDER) + +#define CONSISTENT_DMA_SIZE (1024 * 1024 * 1024) + +static inline struct page * +vduse_domain_get_bounce_page(struct vduse_iova_domain *domain, + unsigned long iova) +{ + unsigned long index = iova >> PAGE_SHIFT; + + return domain->bounce_pages[index]; +} + +static inline void +vduse_domain_set_bounce_page(struct vduse_iova_domain *domain, + unsigned long iova, struct page *page) +{ + unsigned long index = iova >> PAGE_SHIFT; + + domain->bounce_pages[index] = page; +} + +static struct vduse_iova_map * +vduse_domain_alloc_iova_map(struct vduse_iova_domain *domain, + unsigned long iova, unsigned long orig, + size_t size, enum dma_data_direction dir) +{ + struct vduse_iova_map *map; + + map = kzalloc(sizeof(struct vduse_iova_map), GFP_ATOMIC); + if (!map) + return NULL; + + map->iova.start = iova; + map->iova.last = iova + size - 1; + map->orig = orig; + map->size = size; + map->dir = dir; + + return map; +} + +static struct page * +vduse_domain_get_mapping_page(struct vduse_iova_domain *domain, + unsigned long iova) +{ + unsigned long start = iova & PAGE_MASK; + unsigned long last = start + PAGE_SIZE - 1; + struct vduse_iova_map *map; + struct interval_tree_node *node; + struct page *page = NULL; + + spin_lock(&domain->map_lock); + node = interval_tree_iter_first(&domain->mappings, start, last); + if (!node) + goto out; + + map = container_of(node, struct vduse_iova_map, iova); + page = virt_to_page(map->orig + iova - map->iova.start); + get_page(page); +out: + spin_unlock(&domain->map_lock); + + return page; +} + +static struct page * +vduse_domain_alloc_bounce_page(struct vduse_iova_domain *domain, + unsigned long iova) +{ + unsigned long start = iova & PAGE_MASK; + unsigned long last = start + PAGE_SIZE - 1; + struct vduse_iova_map *map; + struct interval_tree_node *node; + struct page *page = NULL, *new_page = alloc_page(GFP_KERNEL); + + if (!new_page) + return NULL; + + spin_lock(&domain->map_lock); + node = interval_tree_iter_first(&domain->mappings, start, last); + if (!node) { + __free_page(new_page); + goto out; + } + page = vduse_domain_get_bounce_page(domain, iova); + if (page) { + get_page(page); + __free_page(new_page); + goto out; + } + vduse_domain_set_bounce_page(domain, iova, new_page); + get_page(new_page); + page = new_page; + + while (node) { + unsigned int src_offset = 0, dst_offset = 0; + void *src, *dst; + size_t copy_len; + + map = container_of(node, struct vduse_iova_map, iova); + node = interval_tree_iter_next(node, start, last); + if (map->dir == DMA_FROM_DEVICE) + continue; + + if (start > map->iova.start) + src_offset = start - map->iova.start; + else + dst_offset = map->iova.start - start; + + src = (void *)(map->orig + src_offset); + dst = page_address(page) + dst_offset; + copy_len = min_t(size_t, map->size - src_offset, + PAGE_SIZE - dst_offset); + memcpy(dst, src, copy_len); + } +out: + spin_unlock(&domain->map_lock); + + return page; +} + +static void +vduse_domain_free_bounce_pages(struct vduse_iova_domain *domain, + unsigned long iova, size_t size) +{ + struct page *page; + struct interval_tree_node *node; + unsigned long last = iova + size - 1; + + spin_lock(&domain->map_lock); + node = interval_tree_iter_first(&domain->mappings, iova, last); + if (WARN_ON(node)) + goto out; + + while (size > 0) { + page = vduse_domain_get_bounce_page(domain, iova); + if (page) { + vduse_domain_set_bounce_page(domain, iova, NULL); + __free_page(page); + } + size -= PAGE_SIZE; + iova += PAGE_SIZE; + } +out: + spin_unlock(&domain->map_lock); +} + +static void vduse_domain_bounce(struct vduse_iova_domain *domain, + unsigned long iova, unsigned long orig, + size_t size, enum dma_data_direction dir) +{ + unsigned int offset = offset_in_page(iova); + + while (size) { + struct page *p = vduse_domain_get_bounce_page(domain, iova); + size_t copy_len = min_t(size_t, PAGE_SIZE - offset, size); + void *addr; + + WARN_ON(!p && dir == DMA_FROM_DEVICE); + + if (p) { + addr = page_address(p) + offset; + if (dir == DMA_TO_DEVICE) + memcpy(addr, (void *)orig, copy_len); + else if (dir == DMA_FROM_DEVICE) + memcpy((void *)orig, addr, copy_len); + } + + size -= copy_len; + orig += copy_len; + iova += copy_len; + offset = 0; + } +} + +static unsigned long vduse_domain_alloc_iova(struct iova_domain *iovad, + unsigned long size, unsigned long limit) +{ + unsigned long shift = iova_shift(iovad); + unsigned long iova_len = iova_align(iovad, size) >> shift; + unsigned long iova_pfn; + + if (iova_len < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1))) + iova_len = roundup_pow_of_two(iova_len); + iova_pfn = alloc_iova_fast(iovad, iova_len, limit >> shift, true); + + return iova_pfn << shift; +} + +static void vduse_domain_free_iova(struct iova_domain *iovad, + unsigned long iova, size_t size) +{ + unsigned long shift = iova_shift(iovad); + unsigned long iova_len = iova_align(iovad, size) >> shift; + + free_iova_fast(iovad, iova >> shift, iova_len); +} + +dma_addr_t vduse_domain_map_page(struct vduse_iova_domain *domain, + struct page *page, unsigned long offset, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct iova_domain *iovad = &domain->stream_iovad; + unsigned long limit = domain->bounce_size - 1; + unsigned long iova = vduse_domain_alloc_iova(iovad, size, limit); + unsigned long orig = (unsigned long)page_address(page) + offset; + struct vduse_iova_map *map; + + if (!iova) + return DMA_MAPPING_ERROR; + + map = vduse_domain_alloc_iova_map(domain, iova, orig, size, dir); + if (!map) { + vduse_domain_free_iova(iovad, iova, size); + return DMA_MAPPING_ERROR; + } + + spin_lock(&domain->map_lock); + interval_tree_insert(&map->iova, &domain->mappings); + spin_unlock(&domain->map_lock); + + if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) + vduse_domain_bounce(domain, iova, orig, size, DMA_TO_DEVICE); + + return (dma_addr_t)iova; +} + +void vduse_domain_unmap_page(struct vduse_iova_domain *domain, + dma_addr_t dma_addr, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + struct iova_domain *iovad = &domain->stream_iovad; + unsigned long iova = (unsigned long)dma_addr; + struct interval_tree_node *node; + struct vduse_iova_map *map; + + spin_lock(&domain->map_lock); + node = interval_tree_iter_first(&domain->mappings, iova, iova + 1); + if (WARN_ON(!node)) { + spin_unlock(&domain->map_lock); + return; + } + interval_tree_remove(node, &domain->mappings); + spin_unlock(&domain->map_lock); + + map = container_of(node, struct vduse_iova_map, iova); + if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) + vduse_domain_bounce(domain, iova, map->orig, + size, DMA_FROM_DEVICE); + vduse_domain_free_iova(iovad, iova, size); + kfree(map); +} + +void *vduse_domain_alloc_coherent(struct vduse_iova_domain *domain, + size_t size, dma_addr_t *dma_addr, + gfp_t flag, unsigned long attrs) +{ + struct iova_domain *iovad = &domain->consistent_iovad; + unsigned long limit = domain->bounce_size + CONSISTENT_DMA_SIZE - 1; + unsigned long iova = vduse_domain_alloc_iova(iovad, size, limit); + void *orig = alloc_pages_exact(size, flag); + struct vduse_iova_map *map; + + if (!iova || !orig) + goto err; + + map = vduse_domain_alloc_iova_map(domain, iova, (unsigned long)orig, + size, DMA_BIDIRECTIONAL); + if (!map) + goto err; + + spin_lock(&domain->map_lock); + interval_tree_insert(&map->iova, &domain->mappings); + spin_unlock(&domain->map_lock); + *dma_addr = (dma_addr_t)iova; + + return orig; +err: + *dma_addr = DMA_MAPPING_ERROR; + if (orig) + free_pages_exact(orig, size); + if (iova) + vduse_domain_free_iova(iovad, iova, size); + + return NULL; +} + +void vduse_domain_free_coherent(struct vduse_iova_domain *domain, size_t size, + void *vaddr, dma_addr_t dma_addr, + unsigned long attrs) +{ + struct iova_domain *iovad = &domain->consistent_iovad; + unsigned long iova = (unsigned long)dma_addr; + struct interval_tree_node *node; + struct vduse_iova_map *map; + + spin_lock(&domain->map_lock); + node = interval_tree_iter_first(&domain->mappings, iova, iova + 1); + if (WARN_ON(!node)) { + spin_unlock(&domain->map_lock); + return; + } + interval_tree_remove(node, &domain->mappings); + spin_unlock(&domain->map_lock); + + map = container_of(node, struct vduse_iova_map, iova); + vduse_domain_free_iova(iovad, iova, size); + free_pages_exact(vaddr, size); + kfree(map); +} + +static vm_fault_t vduse_domain_mmap_fault(struct vm_fault *vmf) +{ + struct vduse_iova_domain *domain = vmf->vma->vm_private_data; + unsigned long iova = vmf->pgoff << PAGE_SHIFT; + struct page *page; + + if (!domain) + return VM_FAULT_SIGBUS; + + if (iova < domain->bounce_size) + page = vduse_domain_alloc_bounce_page(domain, iova); + else + page = vduse_domain_get_mapping_page(domain, iova); + + if (!page) + return VM_FAULT_SIGBUS; + + vmf->page = page; + + return 0; +} + +static const struct vm_operations_struct vduse_domain_mmap_ops = { + .fault = vduse_domain_mmap_fault, +}; + +static int vduse_domain_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct vduse_iova_domain *domain = file->private_data; + + vma->vm_flags |= VM_DONTCOPY | VM_DONTDUMP | VM_DONTEXPAND; + vma->vm_private_data = domain; + vma->vm_ops = &vduse_domain_mmap_ops; + + return 0; +} + +static int vduse_domain_release(struct inode *inode, struct file *file) +{ + struct vduse_iova_domain *domain = file->private_data; + + vduse_domain_free_bounce_pages(domain, 0, domain->bounce_size); + put_iova_domain(&domain->stream_iovad); + put_iova_domain(&domain->consistent_iovad); + vfree(domain->bounce_pages); + kfree(domain); + + return 0; +} + +static const struct file_operations vduse_domain_fops = { + .mmap = vduse_domain_mmap, + .release = vduse_domain_release, +}; + +void vduse_domain_destroy(struct vduse_iova_domain *domain) +{ + fput(domain->file); +} + +struct vduse_iova_domain *vduse_domain_create(size_t bounce_size) +{ + struct vduse_iova_domain *domain; + struct file *file; + unsigned long bounce_pfns = PAGE_ALIGN(bounce_size) >> PAGE_SHIFT; + + domain = kzalloc(sizeof(*domain), GFP_KERNEL); + if (!domain) + return NULL; + + domain->bounce_size = PAGE_ALIGN(bounce_size); + domain->bounce_pages = vzalloc(bounce_pfns * sizeof(struct page *)); + if (!domain->bounce_pages) + goto err_page; + + file = anon_inode_getfile("[vduse-domain]", &vduse_domain_fops, + domain, O_RDWR); + if (IS_ERR(file)) + goto err_file; + + domain->file = file; + spin_lock_init(&domain->map_lock); + domain->mappings = RB_ROOT_CACHED; + init_iova_domain(&domain->stream_iovad, + IOVA_ALLOC_SIZE, IOVA_START_PFN); + init_iova_domain(&domain->consistent_iovad, + PAGE_SIZE, bounce_pfns); + + return domain; +err_file: + vfree(domain->bounce_pages); +err_page: + kfree(domain); + return NULL; +} diff --git a/drivers/vdpa/vdpa_user/iova_domain.h b/drivers/vdpa/vdpa_user/iova_domain.h new file mode 100644 index 000000000000..cc61866acb56 --- /dev/null +++ b/drivers/vdpa/vdpa_user/iova_domain.h @@ -0,0 +1,68 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * MMU-based IOMMU implementation + * + * Copyright (C) 2020 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji + * + */ + +#ifndef _VDUSE_IOVA_DOMAIN_H +#define _VDUSE_IOVA_DOMAIN_H + +#include +#include +#include + +struct vduse_iova_map { + struct interval_tree_node iova; + unsigned long orig; + size_t size; + enum dma_data_direction dir; +}; + +struct vduse_iova_domain { + struct iova_domain stream_iovad; + struct iova_domain consistent_iovad; + struct page **bounce_pages; + size_t bounce_size; + struct rb_root_cached mappings; + spinlock_t map_lock; + struct file *file; +}; + +static inline struct file * +vduse_domain_file(struct vduse_iova_domain *domain) +{ + return domain->file; +} + +static inline unsigned long +vduse_domain_get_offset(struct vduse_iova_domain *domain, unsigned long iova) +{ + return iova; +} + +dma_addr_t vduse_domain_map_page(struct vduse_iova_domain *domain, + struct page *page, unsigned long offset, + size_t size, enum dma_data_direction dir, + unsigned long attrs); + +void vduse_domain_unmap_page(struct vduse_iova_domain *domain, + dma_addr_t dma_addr, size_t size, + enum dma_data_direction dir, unsigned long attrs); + +void *vduse_domain_alloc_coherent(struct vduse_iova_domain *domain, + size_t size, dma_addr_t *dma_addr, + gfp_t flag, unsigned long attrs); + +void vduse_domain_free_coherent(struct vduse_iova_domain *domain, size_t size, + void *vaddr, dma_addr_t dma_addr, + unsigned long attrs); + +void vduse_domain_destroy(struct vduse_iova_domain *domain); + +struct vduse_iova_domain *vduse_domain_create(size_t bounce_size); + +#endif /* _VDUSE_IOVA_DOMAIN_H */ diff --git a/drivers/vdpa/vdpa_user/vduse.h b/drivers/vdpa/vdpa_user/vduse.h new file mode 100644 index 000000000000..3566d229382e --- /dev/null +++ b/drivers/vdpa/vdpa_user/vduse.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * VDUSE: vDPA Device in Userspace + * + * Copyright (C) 2020 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji + * + */ + +#ifndef _VDUSE_H +#define _VDUSE_H + +#include +#include +#include + +#include "iova_domain.h" +#include "eventfd.h" + +struct vduse_virtqueue { + u16 index; + bool ready; + spinlock_t kick_lock; + spinlock_t irq_lock; + struct eventfd_ctx *kickfd; + struct vduse_virqfd *virqfd; + void *private; + irqreturn_t (*cb)(void *data); +}; + +struct vduse_dev; + +struct vduse_vdpa { + struct vdpa_device vdpa; + struct vduse_dev *dev; +}; + +struct vduse_dev { + struct vduse_vdpa *vdev; + struct mutex lock; + struct vduse_virtqueue *vqs; + struct vduse_iova_domain *domain; + struct vhost_iotlb *iommu; + spinlock_t iommu_lock; + atomic_t bounce_map; + spinlock_t msg_lock; + atomic64_t msg_unique; + wait_queue_head_t waitq; + struct list_head send_list; + struct list_head recv_list; + struct list_head list; + bool connected; + u32 id; + u16 vq_size_max; + u16 vq_num; + u32 vq_align; + u32 device_id; + u32 vendor_id; +}; + +#endif /* _VDUSE_H_ */ diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c new file mode 100644 index 000000000000..1cf759bc5914 --- /dev/null +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -0,0 +1,1217 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VDUSE: vDPA Device in Userspace + * + * Copyright (C) 2020 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "vduse.h" + +#define DRV_VERSION "1.0" +#define DRV_AUTHOR "Yongji Xie " +#define DRV_DESC "vDPA Device in Userspace" +#define DRV_LICENSE "GPL v2" + +struct vduse_dev_msg { + struct vduse_dev_request req; + struct vduse_dev_response resp; + struct list_head list; + wait_queue_head_t waitq; + bool completed; + refcount_t refcnt; +}; + +static struct workqueue_struct *vduse_vdpa_wq; +static DEFINE_MUTEX(vduse_lock); +static LIST_HEAD(vduse_devs); + +static inline struct vduse_dev *vdpa_to_vduse(struct vdpa_device *vdpa) +{ + struct vduse_vdpa *vdev = container_of(vdpa, struct vduse_vdpa, vdpa); + + return vdev->dev; +} + +static inline struct vduse_dev *dev_to_vduse(struct device *dev) +{ + struct vdpa_device *vdpa = dev_to_vdpa(dev); + + return vdpa_to_vduse(vdpa); +} + +static struct vduse_dev_msg *vduse_dev_new_msg(struct vduse_dev *dev, int type) +{ + struct vduse_dev_msg *msg = kzalloc(sizeof(*msg), + GFP_KERNEL | __GFP_NOFAIL); + + msg->req.type = type; + msg->req.unique = atomic64_fetch_inc(&dev->msg_unique); + init_waitqueue_head(&msg->waitq); + refcount_set(&msg->refcnt, 1); + + return msg; +} + +static void vduse_dev_msg_get(struct vduse_dev_msg *msg) +{ + refcount_inc(&msg->refcnt); +} + +static void vduse_dev_msg_put(struct vduse_dev_msg *msg) +{ + if (refcount_dec_and_test(&msg->refcnt)) + kfree(msg); +} + +static struct vduse_dev_msg *vduse_dev_find_msg(struct vduse_dev *dev, + struct list_head *head, + uint32_t unique) +{ + struct vduse_dev_msg *tmp, *msg = NULL; + + spin_lock(&dev->msg_lock); + list_for_each_entry(tmp, head, list) { + if (tmp->req.unique == unique) { + msg = tmp; + list_del(&tmp->list); + break; + } + } + spin_unlock(&dev->msg_lock); + + return msg; +} + +static struct vduse_dev_msg *vduse_dev_dequeue_msg(struct vduse_dev *dev, + struct list_head *head) +{ + struct vduse_dev_msg *msg = NULL; + + spin_lock(&dev->msg_lock); + if (!list_empty(head)) { + msg = list_first_entry(head, struct vduse_dev_msg, list); + list_del(&msg->list); + } + spin_unlock(&dev->msg_lock); + + return msg; +} + +static void vduse_dev_enqueue_msg(struct vduse_dev *dev, + struct vduse_dev_msg *msg, struct list_head *head) +{ + spin_lock(&dev->msg_lock); + list_add_tail(&msg->list, head); + spin_unlock(&dev->msg_lock); +} + +static int vduse_dev_msg_sync(struct vduse_dev *dev, struct vduse_dev_msg *msg) +{ + int ret; + + vduse_dev_enqueue_msg(dev, msg, &dev->send_list); + wake_up(&dev->waitq); + wait_event(msg->waitq, msg->completed); + /* coupled with smp_wmb() in vduse_dev_msg_complete() */ + smp_rmb(); + ret = msg->resp.result; + + return ret; +} + +static void vduse_dev_msg_complete(struct vduse_dev_msg *msg, + struct vduse_dev_response *resp) +{ + vduse_dev_msg_get(msg); + memcpy(&msg->resp, resp, sizeof(*resp)); + /* coupled with smp_rmb() in vduse_dev_msg_sync() */ + smp_wmb(); + msg->completed = 1; + wake_up(&msg->waitq); + vduse_dev_msg_put(msg); +} + +static u64 vduse_dev_get_features(struct vduse_dev *dev) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_GET_FEATURES); + u64 features; + + vduse_dev_msg_sync(dev, msg); + features = msg->resp.features; + vduse_dev_msg_put(msg); + + return features; +} + +static int vduse_dev_set_features(struct vduse_dev *dev, u64 features) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_SET_FEATURES); + int ret; + + msg->req.size = sizeof(features); + msg->req.features = features; + + ret = vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); + + return ret; +} + +static u8 vduse_dev_get_status(struct vduse_dev *dev) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_GET_STATUS); + u8 status; + + vduse_dev_msg_sync(dev, msg); + status = msg->resp.status; + vduse_dev_msg_put(msg); + + return status; +} + +static void vduse_dev_set_status(struct vduse_dev *dev, u8 status) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_SET_STATUS); + + msg->req.size = sizeof(status); + msg->req.status = status; + + vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); +} + +static void vduse_dev_get_config(struct vduse_dev *dev, unsigned int offset, + void *buf, unsigned int len) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_GET_CONFIG); + + WARN_ON(len > sizeof(msg->req.config.data)); + + msg->req.size = sizeof(struct vduse_dev_config_data); + msg->req.config.offset = offset; + msg->req.config.len = len; + vduse_dev_msg_sync(dev, msg); + memcpy(buf, msg->resp.config.data, len); + vduse_dev_msg_put(msg); +} + +static void vduse_dev_set_config(struct vduse_dev *dev, unsigned int offset, + const void *buf, unsigned int len) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_SET_CONFIG); + + WARN_ON(len > sizeof(msg->req.config.data)); + + msg->req.size = sizeof(struct vduse_dev_config_data); + msg->req.config.offset = offset; + msg->req.config.len = len; + memcpy(msg->req.config.data, buf, len); + vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); +} + +static void vduse_dev_set_vq_num(struct vduse_dev *dev, + struct vduse_virtqueue *vq, u32 num) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_SET_VQ_NUM); + + msg->req.size = sizeof(struct vduse_vq_num); + msg->req.vq_num.index = vq->index; + msg->req.vq_num.num = num; + + vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); +} + +static int vduse_dev_set_vq_addr(struct vduse_dev *dev, + struct vduse_virtqueue *vq, u64 desc_addr, + u64 driver_addr, u64 device_addr) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_SET_VQ_ADDR); + int ret; + + msg->req.size = sizeof(struct vduse_vq_addr); + msg->req.vq_addr.index = vq->index; + msg->req.vq_addr.desc_addr = desc_addr; + msg->req.vq_addr.driver_addr = driver_addr; + msg->req.vq_addr.device_addr = device_addr; + + ret = vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); + + return ret; +} + +static void vduse_dev_set_vq_ready(struct vduse_dev *dev, + struct vduse_virtqueue *vq, bool ready) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_SET_VQ_READY); + + msg->req.size = sizeof(struct vduse_vq_ready); + msg->req.vq_ready.index = vq->index; + msg->req.vq_ready.ready = ready; + + vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); +} + +static bool vduse_dev_get_vq_ready(struct vduse_dev *dev, + struct vduse_virtqueue *vq) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_GET_VQ_READY); + bool ready; + + msg->req.size = sizeof(struct vduse_vq_ready); + msg->req.vq_ready.index = vq->index; + + vduse_dev_msg_sync(dev, msg); + ready = msg->resp.vq_ready.ready; + vduse_dev_msg_put(msg); + + return ready; +} + +static int vduse_dev_get_vq_state(struct vduse_dev *dev, + struct vduse_virtqueue *vq, + struct vdpa_vq_state *state) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_GET_VQ_STATE); + int ret; + + msg->req.size = sizeof(struct vduse_vq_state); + msg->req.vq_state.index = vq->index; + + ret = vduse_dev_msg_sync(dev, msg); + state->avail_index = msg->resp.vq_state.avail_idx; + vduse_dev_msg_put(msg); + + return ret; +} + +static int vduse_dev_set_vq_state(struct vduse_dev *dev, + struct vduse_virtqueue *vq, + const struct vdpa_vq_state *state) +{ + struct vduse_dev_msg *msg = vduse_dev_new_msg(dev, VDUSE_SET_VQ_STATE); + int ret; + + msg->req.size = sizeof(struct vduse_vq_state); + msg->req.vq_state.index = vq->index; + msg->req.vq_state.avail_idx = state->avail_index; + + ret = vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); + + return ret; +} + +static int vduse_dev_update_iotlb(struct vduse_dev *dev, + u64 start, u64 last) +{ + struct vduse_dev_msg *msg; + int ret; + + if (last < start) + return -EINVAL; + + msg = vduse_dev_new_msg(dev, VDUSE_UPDATE_IOTLB); + msg->req.size = sizeof(struct vduse_iova_range); + msg->req.iova.start = start; + msg->req.iova.last = last; + + ret = vduse_dev_msg_sync(dev, msg); + vduse_dev_msg_put(msg); + + return ret; +} + +static ssize_t vduse_dev_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + struct file *file = iocb->ki_filp; + struct vduse_dev *dev = file->private_data; + struct vduse_dev_msg *msg; + int size = sizeof(struct vduse_dev_request); + ssize_t ret = 0; + + if (iov_iter_count(to) < size) + return 0; + + while (1) { + msg = vduse_dev_dequeue_msg(dev, &dev->send_list); + if (msg) + break; + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + ret = wait_event_interruptible_exclusive(dev->waitq, + !list_empty(&dev->send_list)); + if (ret) + return ret; + } + ret = copy_to_iter(&msg->req, size, to); + if (ret != size) { + vduse_dev_enqueue_msg(dev, msg, &dev->send_list); + return -EFAULT; + } + vduse_dev_enqueue_msg(dev, msg, &dev->recv_list); + + return ret; +} + +static ssize_t vduse_dev_write_iter(struct kiocb *iocb, struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct vduse_dev *dev = file->private_data; + struct vduse_dev_response resp; + struct vduse_dev_msg *msg; + size_t ret; + + ret = copy_from_iter(&resp, sizeof(resp), from); + if (ret != sizeof(resp)) + return -EINVAL; + + msg = vduse_dev_find_msg(dev, &dev->recv_list, resp.unique); + if (!msg) + return -EINVAL; + + vduse_dev_msg_complete(msg, &resp); + + return ret; +} + +static __poll_t vduse_dev_poll(struct file *file, poll_table *wait) +{ + struct vduse_dev *dev = file->private_data; + __poll_t mask = 0; + + poll_wait(file, &dev->waitq, wait); + + if (!list_empty(&dev->send_list)) + mask |= EPOLLIN | EPOLLRDNORM; + + return mask; +} + +static int vduse_iotlb_add_range(struct vduse_dev *dev, + u64 start, u64 last, + u64 addr, unsigned int perm, + struct file *file, u64 offset) +{ + struct vhost_iotlb_file *iotlb_file; + int ret; + + iotlb_file = kmalloc(sizeof(*iotlb_file), GFP_ATOMIC); + if (!iotlb_file) + return -ENOMEM; + + iotlb_file->file = get_file(file); + iotlb_file->offset = offset; + + spin_lock(&dev->iommu_lock); + ret = vhost_iotlb_add_range(dev->iommu, start, last, + addr, perm, iotlb_file); + spin_unlock(&dev->iommu_lock); + if (ret) { + fput(iotlb_file->file); + kfree(iotlb_file); + return ret; + } + return 0; +} + +static void vduse_iotlb_del_range(struct vduse_dev *dev, u64 start, u64 last) +{ + struct vhost_iotlb_file *iotlb_file; + struct vhost_iotlb_map *map; + + spin_lock(&dev->iommu_lock); + while ((map = vhost_iotlb_itree_first(dev->iommu, start, last))) { + iotlb_file = (struct vhost_iotlb_file *)map->opaque; + fput(iotlb_file->file); + kfree(iotlb_file); + vhost_iotlb_map_free(dev->iommu, map); + } + spin_unlock(&dev->iommu_lock); +} + +static void vduse_dev_reset(struct vduse_dev *dev) +{ + int i; + + atomic_set(&dev->bounce_map, 0); + vduse_iotlb_del_range(dev, 0ULL, 0ULL - 1); + vduse_dev_update_iotlb(dev, 0ULL, 0ULL - 1); + + for (i = 0; i < dev->vq_num; i++) { + struct vduse_virtqueue *vq = &dev->vqs[i]; + + spin_lock(&vq->irq_lock); + vq->ready = false; + vq->cb = NULL; + vq->private = NULL; + spin_unlock(&vq->irq_lock); + } +} + +static int vduse_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 idx, + u64 desc_area, u64 driver_area, + u64 device_area) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + return vduse_dev_set_vq_addr(dev, vq, desc_area, + driver_area, device_area); +} + +static void vduse_vdpa_kick_vq(struct vdpa_device *vdpa, u16 idx) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vduse_vq_kick(vq); +} + +static void vduse_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 idx, + struct vdpa_callback *cb) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vq->cb = cb->callback; + vq->private = cb->private; +} + +static void vduse_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 idx, u32 num) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vduse_dev_set_vq_num(dev, vq, num); +} + +static void vduse_vdpa_set_vq_ready(struct vdpa_device *vdpa, + u16 idx, bool ready) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vduse_dev_set_vq_ready(dev, vq, ready); + vq->ready = ready; +} + +static bool vduse_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 idx) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vq->ready = vduse_dev_get_vq_ready(dev, vq); + + return vq->ready; +} + +static int vduse_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 idx, + const struct vdpa_vq_state *state) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + return vduse_dev_set_vq_state(dev, vq, state); +} + +static int vduse_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 idx, + struct vdpa_vq_state *state) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + return vduse_dev_get_vq_state(dev, vq, state); +} + +static u32 vduse_vdpa_get_vq_align(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->vq_align; +} + +static u64 vduse_vdpa_get_features(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + u64 fixed = (1ULL << VIRTIO_F_ACCESS_PLATFORM); + + return (vduse_dev_get_features(dev) | fixed); +} + +static int vduse_vdpa_set_features(struct vdpa_device *vdpa, u64 features) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return vduse_dev_set_features(dev, features); +} + +static void vduse_vdpa_set_config_cb(struct vdpa_device *vdpa, + struct vdpa_callback *cb) +{ + /* We don't support config interrupt */ +} + +static u16 vduse_vdpa_get_vq_num_max(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->vq_size_max; +} + +static u32 vduse_vdpa_get_device_id(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->device_id; +} + +static u32 vduse_vdpa_get_vendor_id(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->vendor_id; +} + +static u8 vduse_vdpa_get_status(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return vduse_dev_get_status(dev); +} + +static void vduse_vdpa_set_status(struct vdpa_device *vdpa, u8 status) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + if (status == 0) + vduse_dev_reset(dev); + else + vduse_dev_update_iotlb(dev, 0ULL, 0ULL - 1); + + vduse_dev_set_status(dev, status); +} + +static void vduse_vdpa_get_config(struct vdpa_device *vdpa, unsigned int offset, + void *buf, unsigned int len) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + vduse_dev_get_config(dev, offset, buf, len); +} + +static void vduse_vdpa_set_config(struct vdpa_device *vdpa, unsigned int offset, + const void *buf, unsigned int len) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + vduse_dev_set_config(dev, offset, buf, len); +} + +static int vduse_vdpa_set_map(struct vdpa_device *vdpa, + struct vhost_iotlb *iotlb) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vhost_iotlb_map *map; + struct vhost_iotlb_file *iotlb_file; + u64 start = 0ULL, last = 0ULL - 1; + int ret = 0; + + vduse_iotlb_del_range(dev, start, last); + + for (map = vhost_iotlb_itree_first(iotlb, start, last); map; + map = vhost_iotlb_itree_next(map, start, last)) { + if (!map->opaque) + continue; + + iotlb_file = (struct vhost_iotlb_file *)map->opaque; + ret = vduse_iotlb_add_range(dev, map->start, map->last, + map->addr, map->perm, + iotlb_file->file, + iotlb_file->offset); + if (ret) + break; + } + vduse_dev_update_iotlb(dev, start, last); + + return ret; +} + +static void vduse_vdpa_free(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + WARN_ON(!list_empty(&dev->send_list)); + WARN_ON(!list_empty(&dev->recv_list)); + dev->vdev = NULL; +} + +static const struct vdpa_config_ops vduse_vdpa_config_ops = { + .set_vq_address = vduse_vdpa_set_vq_address, + .kick_vq = vduse_vdpa_kick_vq, + .set_vq_cb = vduse_vdpa_set_vq_cb, + .set_vq_num = vduse_vdpa_set_vq_num, + .set_vq_ready = vduse_vdpa_set_vq_ready, + .get_vq_ready = vduse_vdpa_get_vq_ready, + .set_vq_state = vduse_vdpa_set_vq_state, + .get_vq_state = vduse_vdpa_get_vq_state, + .get_vq_align = vduse_vdpa_get_vq_align, + .get_features = vduse_vdpa_get_features, + .set_features = vduse_vdpa_set_features, + .set_config_cb = vduse_vdpa_set_config_cb, + .get_vq_num_max = vduse_vdpa_get_vq_num_max, + .get_device_id = vduse_vdpa_get_device_id, + .get_vendor_id = vduse_vdpa_get_vendor_id, + .get_status = vduse_vdpa_get_status, + .set_status = vduse_vdpa_set_status, + .get_config = vduse_vdpa_get_config, + .set_config = vduse_vdpa_set_config, + .set_map = vduse_vdpa_set_map, + .free = vduse_vdpa_free, +}; + +static dma_addr_t vduse_dev_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + if (atomic_xchg(&vdev->bounce_map, 1) == 0 && + vduse_iotlb_add_range(vdev, 0, domain->bounce_size - 1, + 0, VDUSE_ACCESS_RW, + vduse_domain_file(domain), + vduse_domain_get_offset(domain, 0))) { + atomic_set(&vdev->bounce_map, 0); + return DMA_MAPPING_ERROR; + } + + return vduse_domain_map_page(domain, page, offset, size, dir, attrs); +} + +static void vduse_dev_unmap_page(struct device *dev, dma_addr_t dma_addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + return vduse_domain_unmap_page(domain, dma_addr, size, dir, attrs); +} + +static void *vduse_dev_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_addr, gfp_t flag, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + unsigned long iova; + void *addr; + + *dma_addr = DMA_MAPPING_ERROR; + addr = vduse_domain_alloc_coherent(domain, size, + (dma_addr_t *)&iova, flag, attrs); + if (!addr) + return NULL; + + if (vduse_iotlb_add_range(vdev, iova, iova + size - 1, + iova, VDUSE_ACCESS_RW, + vduse_domain_file(domain), + vduse_domain_get_offset(domain, iova))) { + vduse_domain_free_coherent(domain, size, addr, iova, attrs); + return NULL; + } + *dma_addr = (dma_addr_t)iova; + + return addr; +} + +static void vduse_dev_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_addr, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + unsigned long start = (unsigned long)dma_addr; + unsigned long last = start + size - 1; + + vduse_iotlb_del_range(vdev, start, last); + vduse_dev_update_iotlb(vdev, start, last); + vduse_domain_free_coherent(domain, size, vaddr, dma_addr, attrs); +} + +static const struct dma_map_ops vduse_dev_dma_ops = { + .map_page = vduse_dev_map_page, + .unmap_page = vduse_dev_unmap_page, + .alloc = vduse_dev_alloc_coherent, + .free = vduse_dev_free_coherent, +}; + +static unsigned int perm_to_file_flags(u8 perm) +{ + unsigned int flags = 0; + + switch (perm) { + case VDUSE_ACCESS_WO: + flags |= O_WRONLY; + break; + case VDUSE_ACCESS_RO: + flags |= O_RDONLY; + break; + case VDUSE_ACCESS_RW: + flags |= O_RDWR; + break; + default: + WARN(1, "invalidate vhost IOTLB permission\n"); + break; + } + + return flags; +} + +static long vduse_dev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct vduse_dev *dev = file->private_data; + void __user *argp = (void __user *)arg; + int ret; + + mutex_lock(&dev->lock); + switch (cmd) { + case VDUSE_IOTLB_GET_FD: { + struct vduse_iotlb_entry entry; + struct vhost_iotlb_map *map; + struct vhost_iotlb_file *iotlb_file; + struct file *f = NULL; + + ret = -EFAULT; + if (copy_from_user(&entry, argp, sizeof(entry))) + break; + + spin_lock(&dev->iommu_lock); + map = vhost_iotlb_itree_first(dev->iommu, entry.start, + entry.last); + if (map) { + iotlb_file = (struct vhost_iotlb_file *)map->opaque; + f = get_file(iotlb_file->file); + entry.offset = iotlb_file->offset; + entry.start = map->start; + entry.last = map->last; + entry.perm = map->perm; + } + spin_unlock(&dev->iommu_lock); + if (!f) { + ret = -EINVAL; + break; + } + if (copy_to_user(argp, &entry, sizeof(entry))) { + fput(f); + ret = -EFAULT; + break; + } + ret = get_unused_fd_flags(perm_to_file_flags(entry.perm)); + if (ret < 0) { + fput(f); + break; + } + fd_install(ret, f); + break; + } + case VDUSE_VQ_SETUP_KICKFD: { + struct vduse_vq_eventfd eventfd; + + ret = -EFAULT; + if (copy_from_user(&eventfd, argp, sizeof(eventfd))) + break; + + ret = vduse_kickfd_setup(dev, &eventfd); + break; + } + case VDUSE_VQ_SETUP_IRQFD: { + struct vduse_vq_eventfd eventfd; + + ret = -EFAULT; + if (copy_from_user(&eventfd, argp, sizeof(eventfd))) + break; + + ret = vduse_virqfd_setup(dev, &eventfd); + break; + } + } + mutex_unlock(&dev->lock); + + return ret; +} + +static int vduse_dev_release(struct inode *inode, struct file *file) +{ + struct vduse_dev *dev = file->private_data; + + vduse_kickfd_release(dev); + vduse_virqfd_release(dev); + dev->connected = false; + + return 0; +} + +static const struct file_operations vduse_dev_fops = { + .owner = THIS_MODULE, + .release = vduse_dev_release, + .read_iter = vduse_dev_read_iter, + .write_iter = vduse_dev_write_iter, + .poll = vduse_dev_poll, + .unlocked_ioctl = vduse_dev_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .llseek = noop_llseek, +}; + +static struct vduse_dev *vduse_dev_create(void) +{ + struct vduse_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL); + + if (!dev) + return NULL; + + dev->iommu = vhost_iotlb_alloc(2048, 0); + if (!dev->iommu) { + kfree(dev); + return NULL; + } + + mutex_init(&dev->lock); + spin_lock_init(&dev->msg_lock); + INIT_LIST_HEAD(&dev->send_list); + INIT_LIST_HEAD(&dev->recv_list); + atomic64_set(&dev->msg_unique, 0); + spin_lock_init(&dev->iommu_lock); + atomic_set(&dev->bounce_map, 0); + + init_waitqueue_head(&dev->waitq); + + return dev; +} + +static void vduse_dev_destroy(struct vduse_dev *dev) +{ + vhost_iotlb_free(dev->iommu); + mutex_destroy(&dev->lock); + kfree(dev); +} + +static struct vduse_dev *vduse_find_dev(u32 id) +{ + struct vduse_dev *tmp, *dev = NULL; + + list_for_each_entry(tmp, &vduse_devs, list) { + if (tmp->id == id) { + dev = tmp; + break; + } + } + return dev; +} + +static int vduse_destroy_dev(u32 id) +{ + struct vduse_dev *dev = vduse_find_dev(id); + + if (!dev) + return -EINVAL; + + if (dev->vdev || dev->connected) + return -EBUSY; + + list_del(&dev->list); + kfree(dev->vqs); + vduse_domain_destroy(dev->domain); + vduse_dev_destroy(dev); + + return 0; +} + +static int vduse_create_dev(struct vduse_dev_config *config) +{ + int i, fd; + struct vduse_dev *dev; + char name[64]; + + if (vduse_find_dev(config->id)) + return -EEXIST; + + dev = vduse_dev_create(); + if (!dev) + return -ENOMEM; + + dev->id = config->id; + dev->device_id = config->device_id; + dev->vendor_id = config->vendor_id; + dev->domain = vduse_domain_create(config->bounce_size); + if (!dev->domain) + goto err_domain; + + dev->vq_align = config->vq_align; + dev->vq_size_max = config->vq_size_max; + dev->vq_num = config->vq_num; + dev->vqs = kcalloc(dev->vq_num, sizeof(*dev->vqs), GFP_KERNEL); + if (!dev->vqs) + goto err_vqs; + + for (i = 0; i < dev->vq_num; i++) { + dev->vqs[i].index = i; + spin_lock_init(&dev->vqs[i].kick_lock); + spin_lock_init(&dev->vqs[i].irq_lock); + } + + snprintf(name, sizeof(name), "[vduse-dev:%u]", config->id); + fd = anon_inode_getfd(name, &vduse_dev_fops, dev, O_RDWR | O_CLOEXEC); + if (fd < 0) + goto err_fd; + + dev->connected = true; + list_add(&dev->list, &vduse_devs); + + return fd; +err_fd: + kfree(dev->vqs); +err_vqs: + vduse_domain_destroy(dev->domain); +err_domain: + vduse_dev_destroy(dev); + return fd; +} + +static long vduse_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int ret; + void __user *argp = (void __user *)arg; + + mutex_lock(&vduse_lock); + switch (cmd) { + case VDUSE_CREATE_DEV: { + struct vduse_dev_config config; + + ret = -EFAULT; + if (copy_from_user(&config, argp, sizeof(config))) + break; + + ret = vduse_create_dev(&config); + break; + } + case VDUSE_DESTROY_DEV: + ret = vduse_destroy_dev(arg); + break; + default: + ret = -EINVAL; + break; + } + mutex_unlock(&vduse_lock); + + return ret; +} + +static const struct file_operations vduse_fops = { + .owner = THIS_MODULE, + .unlocked_ioctl = vduse_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .llseek = noop_llseek, +}; + +static struct miscdevice vduse_misc = { + .fops = &vduse_fops, + .minor = MISC_DYNAMIC_MINOR, + .name = "vduse", +}; + +static void vduse_parent_release(struct device *dev) +{ +} + +static struct device vduse_parent = { + .init_name = "vduse", + .release = vduse_parent_release, +}; + +static struct vdpa_parent_dev parent_dev; + +static int vduse_dev_add_vdpa(struct vduse_dev *dev, const char *name) +{ + struct vduse_vdpa *vdev = dev->vdev; + int ret; + + if (vdev) + return -EEXIST; + + vdev = vdpa_alloc_device(struct vduse_vdpa, vdpa, NULL, + &vduse_vdpa_config_ops, + dev->vq_num, name, true); + if (!vdev) + return -ENOMEM; + + vdev->dev = dev; + vdev->vdpa.dev.dma_mask = &vdev->vdpa.dev.coherent_dma_mask; + ret = dma_set_mask_and_coherent(&vdev->vdpa.dev, DMA_BIT_MASK(64)); + if (ret) + goto err; + + set_dma_ops(&vdev->vdpa.dev, &vduse_dev_dma_ops); + vdev->vdpa.dma_dev = &vdev->vdpa.dev; + vdev->vdpa.pdev = &parent_dev; + + ret = _vdpa_register_device(&vdev->vdpa); + if (ret) + goto err; + + dev->vdev = vdev; + + return 0; +err: + put_device(&vdev->vdpa.dev); + return ret; +} + +static struct vdpa_device *vdpa_dev_add(struct vdpa_parent_dev *pdev, + const char *name, u32 device_id, + struct nlattr **attrs) +{ + u32 vduse_id; + struct vduse_dev *dev; + int ret = -EINVAL; + + if (!attrs[VDPA_ATTR_BACKEND_ID]) + return ERR_PTR(-EINVAL); + + mutex_lock(&vduse_lock); + vduse_id = nla_get_u32(attrs[VDPA_ATTR_BACKEND_ID]); + dev = vduse_find_dev(vduse_id); + if (!dev) + goto unlock; + + if (dev->device_id != device_id) + goto unlock; + + ret = vduse_dev_add_vdpa(dev, name); +unlock: + mutex_unlock(&vduse_lock); + if (ret) + return ERR_PTR(ret); + + return &dev->vdev->vdpa; +} + +static void vdpa_dev_del(struct vdpa_parent_dev *pdev, struct vdpa_device *dev) +{ + _vdpa_unregister_device(dev); +} + +static const struct vdpa_dev_ops vdpa_dev_parent_ops = { + .dev_add = vdpa_dev_add, + .dev_del = vdpa_dev_del +}; + +static struct virtio_device_id id_table[] = { + { VIRTIO_DEV_ANY_ID, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static struct vdpa_parent_dev parent_dev = { + .device = &vduse_parent, + .id_table = id_table, + .ops = &vdpa_dev_parent_ops, +}; + +static int vduse_parentdev_init(void) +{ + int ret; + + ret = device_register(&vduse_parent); + if (ret) + return ret; + + ret = vdpa_parentdev_register(&parent_dev); + if (ret) + goto err; + + return 0; +err: + device_unregister(&vduse_parent); + return ret; +} + +static void vduse_parentdev_exit(void) +{ + vdpa_parentdev_unregister(&parent_dev); + device_unregister(&vduse_parent); +} + +static int vduse_init(void) +{ + int ret; + + ret = misc_register(&vduse_misc); + if (ret) + return ret; + + ret = -ENOMEM; + vduse_vdpa_wq = alloc_workqueue("vduse-vdpa", WQ_UNBOUND, 1); + if (!vduse_vdpa_wq) + goto err_vdpa_wq; + + ret = vduse_virqfd_init(); + if (ret) + goto err_irqfd; + + ret = vduse_parentdev_init(); + if (ret) + goto err_parentdev; + + return 0; +err_parentdev: + vduse_virqfd_exit(); +err_irqfd: + destroy_workqueue(vduse_vdpa_wq); +err_vdpa_wq: + misc_deregister(&vduse_misc); + return ret; +} +module_init(vduse_init); + +static void vduse_exit(void) +{ + misc_deregister(&vduse_misc); + destroy_workqueue(vduse_vdpa_wq); + vduse_virqfd_exit(); + vduse_parentdev_exit(); +} +module_exit(vduse_exit); + +MODULE_VERSION(DRV_VERSION); +MODULE_LICENSE(DRV_LICENSE); +MODULE_AUTHOR(DRV_AUTHOR); +MODULE_DESCRIPTION(DRV_DESC); diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h index bba8b83a94b5..a7a841e5ffc7 100644 --- a/include/uapi/linux/vdpa.h +++ b/include/uapi/linux/vdpa.h @@ -33,6 +33,7 @@ enum vdpa_attr { VDPA_ATTR_DEV_VENDOR_ID, /* u32 */ VDPA_ATTR_DEV_MAX_VQS, /* u32 */ VDPA_ATTR_DEV_MAX_VQ_SIZE, /* u16 */ + VDPA_ATTR_BACKEND_ID, /* u32 */ /* new attributes must be added above here */ VDPA_ATTR_MAX, diff --git a/include/uapi/linux/vduse.h b/include/uapi/linux/vduse.h new file mode 100644 index 000000000000..9fb555ddcfbd --- /dev/null +++ b/include/uapi/linux/vduse.h @@ -0,0 +1,125 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_VDUSE_H_ +#define _UAPI_VDUSE_H_ + +#include + +/* the control messages definition for read/write */ + +#define VDUSE_CONFIG_DATA_LEN 256 + +enum vduse_req_type { + VDUSE_SET_VQ_NUM, + VDUSE_SET_VQ_ADDR, + VDUSE_SET_VQ_READY, + VDUSE_GET_VQ_READY, + VDUSE_SET_VQ_STATE, + VDUSE_GET_VQ_STATE, + VDUSE_SET_FEATURES, + VDUSE_GET_FEATURES, + VDUSE_SET_STATUS, + VDUSE_GET_STATUS, + VDUSE_SET_CONFIG, + VDUSE_GET_CONFIG, + VDUSE_UPDATE_IOTLB, +}; + +struct vduse_vq_num { + __u32 index; + __u32 num; +}; + +struct vduse_vq_addr { + __u32 index; + __u64 desc_addr; + __u64 driver_addr; + __u64 device_addr; +}; + +struct vduse_vq_ready { + __u32 index; + __u8 ready; +}; + +struct vduse_vq_state { + __u32 index; + __u16 avail_idx; +}; + +struct vduse_dev_config_data { + __u32 offset; + __u32 len; + __u8 data[VDUSE_CONFIG_DATA_LEN]; +}; + +struct vduse_iova_range { + __u64 start; + __u64 last; +}; + +struct vduse_dev_request { + __u32 type; /* request type */ + __u32 unique; /* request id */ + __u32 flags; /* request flags */ + __u32 size; /* the payload size */ + union { + struct vduse_vq_num vq_num; /* virtqueue num */ + struct vduse_vq_addr vq_addr; /* virtqueue address */ + struct vduse_vq_ready vq_ready; /* virtqueue ready status */ + struct vduse_vq_state vq_state; /* virtqueue state */ + struct vduse_dev_config_data config; /* virtio device config space */ + struct vduse_iova_range iova; /* iova range for updating */ + __u64 features; /* virtio features */ + __u8 status; /* device status */ + }; +}; + +struct vduse_dev_response { + __u32 unique; /* corresponding request id */ + __s32 result; /* the result of request */ + union { + struct vduse_vq_ready vq_ready; /* virtqueue ready status */ + struct vduse_vq_state vq_state; /* virtqueue state */ + struct vduse_dev_config_data config; /* virtio device config space */ + __u64 features; /* virtio features */ + __u8 status; /* device status */ + }; +}; + +/* ioctls */ + +struct vduse_dev_config { + __u32 id; /* vduse device id */ + __u32 vendor_id; /* virtio vendor id */ + __u32 device_id; /* virtio device id */ + __u64 bounce_size; /* bounce buffer size for iommu */ + __u16 vq_num; /* the number of virtqueues */ + __u16 vq_size_max; /* the max size of virtqueue */ + __u32 vq_align; /* the allocation alignment of virtqueue's metadata */ +}; + +struct vduse_iotlb_entry { + __u64 offset; /* the mmap offset on fd */ + __u64 start; /* start of the IOVA range */ + __u64 last; /* last of the IOVA range */ +#define VDUSE_ACCESS_RO 0x1 +#define VDUSE_ACCESS_WO 0x2 +#define VDUSE_ACCESS_RW 0x3 + __u8 perm; /* access permission of this range */ +}; + +struct vduse_vq_eventfd { + __u32 index; /* virtqueue index */ + __u32 fd; /* eventfd */ +}; + +#define VDUSE_BASE 0x81 + +#define VDUSE_CREATE_DEV _IOW(VDUSE_BASE, 0x01, struct vduse_dev_config) +#define VDUSE_DESTROY_DEV _IO(VDUSE_BASE, 0x02) + +#define VDUSE_IOTLB_GET_FD _IOWR(VDUSE_BASE, 0x04, struct vduse_iotlb_entry) +#define VDUSE_VQ_SETUP_KICKFD _IOW(VDUSE_BASE, 0x05, struct vduse_vq_eventfd) +#define VDUSE_VQ_SETUP_IRQFD _IOW(VDUSE_BASE, 0x06, struct vduse_vq_eventfd) + +#endif /* _UAPI_VDUSE_H_ */ From patchwork Tue Jan 19 05:07:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 366748 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7EB96C433DB for ; Tue, 19 Jan 2021 07:18:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42DA123134 for ; Tue, 19 Jan 2021 07:18:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389967AbhASF0L (ORCPT ); Tue, 19 Jan 2021 00:26:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45270 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388935AbhASFKX (ORCPT ); Tue, 19 Jan 2021 00:10:23 -0500 Received: from mail-pj1-x1036.google.com (mail-pj1-x1036.google.com [IPv6:2607:f8b0:4864:20::1036]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A970DC061786 for ; Mon, 18 Jan 2021 21:08:28 -0800 (PST) Received: by mail-pj1-x1036.google.com with SMTP id u4so11361703pjn.4 for ; Mon, 18 Jan 2021 21:08:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=t3cY7CxP1IBzVsJGjcj8blqMZcQjokVEop4ReGoC7JE=; b=TEg+IOYZST+7tYQUg1/prfYMdgJIbYGfE5jH4E7BZIml0/hSPCz3KbwjSxXpiQsRZl Q8l81z+hVG6Xt72wYh15Fo9jMa24fzcmQCqN0jO7hAIdtR0TT33wJSAbVOWl9nN8CbeH wthbRRKu8tL9b6om9Gse2Y+8qcuWq6CPO464iUnoiGhSclGpRl6VRQRui7JsBJKTiryh nT2XiZjYh14ExYSPwYhUXBdjgi2iXgBRnrc8XAJ6hUI7UtJJEdnVGAiHrblWDqwaLew/ +hAHfdNaVBy4QKfKFunM1DoBJJsowjZWgC/OW7bwcXDqwZCi3+nYNwcXHJCSeBVyWGXo T6bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=t3cY7CxP1IBzVsJGjcj8blqMZcQjokVEop4ReGoC7JE=; b=ZhEYP6qBxcfI9LRRGKmfxLE/+9YMxmxWlhPep3XOzXwBjTriAGJ0q50/IwnmwAZdiC dB8lnnLHgjU/OU9ePKeI90pxBlmrSoCiUptLBeRsWFMPI4LonvhWBoruYW1e1gJd9dBf WuMgZZmHXkozea5wNdglLCPokURiwt42tJ4PMAjAa8ll3t5VrZC2JJ2PlnY5VZmobivg 8ucJhEtEnq2fpFtU/HfkAjHx29K21tlPt6QXYzIagA4qKPZqDbo0bnUT9M35wpFwZ2WZ zNI4LMIVXBelk0OPmdw+MO2Mr+/Tr9mauBPEJcaUSXMMvF4Vt0L8Q/eYFFimJ+AbbgtK QzfA== X-Gm-Message-State: AOAM5326ug8NKatnURUsM7OMyMdHzNIpD7Vxly/lBvTA10qiDLvwGP2O +eOeq14A9HKmyXSzTLWWUbv2 X-Google-Smtp-Source: ABdhPJzuUPBsbXsliQWe6YeR9pV9Pcl1Qlp+OOESCFCSFdZxLsSlgkaLNNMDIGMzQUlolElY5qtofw== X-Received: by 2002:a17:903:230b:b029:dd:7cf1:8c33 with SMTP id d11-20020a170903230bb02900dd7cf18c33mr2894021plh.31.1611032908304; Mon, 18 Jan 2021 21:08:28 -0800 (PST) Received: from localhost ([139.177.225.243]) by smtp.gmail.com with ESMTPSA id i2sm1125169pjd.21.2021.01.18.21.08.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jan 2021 21:08:27 -0800 (PST) From: Xie Yongji To: mst@redhat.com, jasowang@redhat.com, stefanha@redhat.com, sgarzare@redhat.com, parav@nvidia.com, bob.liu@oracle.com, hch@infradead.org, rdunlap@infradead.org, willy@infradead.org, viro@zeniv.linux.org.uk, axboe@kernel.dk, bcrl@kvack.org, corbet@lwn.net Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org Subject: [RFC v3 10/11] vduse: grab the module's references until there is no vduse device Date: Tue, 19 Jan 2021 13:07:55 +0800 Message-Id: <20210119050756.600-4-xieyongji@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210119050756.600-1-xieyongji@bytedance.com> References: <20210119045920.447-1-xieyongji@bytedance.com> <20210119050756.600-1-xieyongji@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The module should not be unloaded if any vduse device exists. So increase the module's reference count when creating vduse device. And the reference count is kept until the device is destroyed. Signed-off-by: Xie Yongji --- drivers/vdpa/vdpa_user/vduse_dev.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 4d21203da5b6..003aeb281bce 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -978,6 +978,7 @@ static int vduse_destroy_dev(u32 id) kfree(dev->vqs); vduse_domain_destroy(dev->domain); vduse_dev_destroy(dev); + module_put(THIS_MODULE); return 0; } @@ -1022,6 +1023,7 @@ static int vduse_create_dev(struct vduse_dev_config *config) dev->connected = true; list_add(&dev->list, &vduse_devs); + __module_get(THIS_MODULE); return fd; err_fd: