From patchwork Tue Apr 23 05:54:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10911939 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0996C1708 for ; Tue, 23 Apr 2019 05:54:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F138628733 for ; Tue, 23 Apr 2019 05:54:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E4EED28738; Tue, 23 Apr 2019 05:54:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 92CC128736 for ; Tue, 23 Apr 2019 05:54:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726146AbfDWFyi (ORCPT ); Tue, 23 Apr 2019 01:54:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54486 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725888AbfDWFyh (ORCPT ); Tue, 23 Apr 2019 01:54:37 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 62C47307D8BE; Tue, 23 Apr 2019 05:54:37 +0000 (UTC) Received: from hp-dl380pg8-01.lab.eng.pek2.redhat.com (hp-dl380pg8-01.lab.eng.pek2.redhat.com [10.73.8.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5F53119C7E; Tue, 23 Apr 2019 05:54:32 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterx@redhat.com, aarcange@redhat.com, James.Bottomley@hansenpartnership.com, hch@infradead.org, davem@davemloft.net, jglisse@redhat.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, christophe.de.dinechin@gmail.com, jrdr.linux@gmail.com Subject: [RFC PATCH V3 1/6] vhost: generalize adding used elem Date: Tue, 23 Apr 2019 01:54:15 -0400 Message-Id: <20190423055420.26408-2-jasowang@redhat.com> In-Reply-To: <20190423055420.26408-1-jasowang@redhat.com> References: <20190423055420.26408-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Tue, 23 Apr 2019 05:54:37 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Use one generic vhost_copy_to_user() instead of two dedicated accessor. This will simplify the conversion to fine grain accessors. About 2% improvement of PPS were seen during vitio-user txonly test. Signed-off-by: Jason Wang --- drivers/vhost/vhost.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 351af88231ad..6df76ac8200a 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2255,16 +2255,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, start = vq->last_used_idx & (vq->num - 1); used = vq->used->ring + start; - if (count == 1) { - if (vhost_put_user(vq, heads[0].id, &used->id)) { - vq_err(vq, "Failed to write used id"); - return -EFAULT; - } - if (vhost_put_user(vq, heads[0].len, &used->len)) { - vq_err(vq, "Failed to write used len"); - return -EFAULT; - } - } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) { + if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) { vq_err(vq, "Failed to write used"); return -EFAULT; } From patchwork Tue Apr 23 05:54:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10911943 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C370D112C for ; Tue, 23 Apr 2019 05:54:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B2F8428736 for ; Tue, 23 Apr 2019 05:54:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A712F28762; Tue, 23 Apr 2019 05:54:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0FDBF28736 for ; Tue, 23 Apr 2019 05:54:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726218AbfDWFyo (ORCPT ); Tue, 23 Apr 2019 01:54:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36920 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725888AbfDWFyn (ORCPT ); Tue, 23 Apr 2019 01:54:43 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 01BB185A04; Tue, 23 Apr 2019 05:54:43 +0000 (UTC) Received: from hp-dl380pg8-01.lab.eng.pek2.redhat.com (hp-dl380pg8-01.lab.eng.pek2.redhat.com [10.73.8.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id DD4BF19C7E; Tue, 23 Apr 2019 05:54:37 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterx@redhat.com, aarcange@redhat.com, James.Bottomley@hansenpartnership.com, hch@infradead.org, davem@davemloft.net, jglisse@redhat.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, christophe.de.dinechin@gmail.com, jrdr.linux@gmail.com Subject: [RFC PATCH V3 2/6] vhost: fine grain userspace memory accessors Date: Tue, 23 Apr 2019 01:54:16 -0400 Message-Id: <20190423055420.26408-3-jasowang@redhat.com> In-Reply-To: <20190423055420.26408-1-jasowang@redhat.com> References: <20190423055420.26408-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Tue, 23 Apr 2019 05:54:43 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This is used to hide the metadata address from virtqueue helpers. This will allow to implement a vmap based fast accessing to metadata. Signed-off-by: Jason Wang --- drivers/vhost/vhost.c | 94 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 77 insertions(+), 17 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 6df76ac8200a..7335f2275ed3 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -869,6 +869,34 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq, ret; \ }) +static inline int vhost_put_avail_event(struct vhost_virtqueue *vq) +{ + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), + vhost_avail_event(vq)); +} + +static inline int vhost_put_used(struct vhost_virtqueue *vq, + struct vring_used_elem *head, int idx, + int count) +{ + return vhost_copy_to_user(vq, vq->used->ring + idx, head, + count * sizeof(*head)); +} + +static inline int vhost_put_used_flags(struct vhost_virtqueue *vq) + +{ + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), + &vq->used->flags); +} + +static inline int vhost_put_used_idx(struct vhost_virtqueue *vq) + +{ + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), + &vq->used->idx); +} + #define vhost_get_user(vq, x, ptr, type) \ ({ \ int ret; \ @@ -907,6 +935,43 @@ static void vhost_dev_unlock_vqs(struct vhost_dev *d) mutex_unlock(&d->vqs[i]->mutex); } +static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq, + __virtio16 *idx) +{ + return vhost_get_avail(vq, *idx, &vq->avail->idx); +} + +static inline int vhost_get_avail_head(struct vhost_virtqueue *vq, + __virtio16 *head, int idx) +{ + return vhost_get_avail(vq, *head, + &vq->avail->ring[idx & (vq->num - 1)]); +} + +static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq, + __virtio16 *flags) +{ + return vhost_get_avail(vq, *flags, &vq->avail->flags); +} + +static inline int vhost_get_used_event(struct vhost_virtqueue *vq, + __virtio16 *event) +{ + return vhost_get_avail(vq, *event, vhost_used_event(vq)); +} + +static inline int vhost_get_used_idx(struct vhost_virtqueue *vq, + __virtio16 *idx) +{ + return vhost_get_used(vq, *idx, &vq->used->idx); +} + +static inline int vhost_get_desc(struct vhost_virtqueue *vq, + struct vring_desc *desc, int idx) +{ + return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc)); +} + static int vhost_new_umem_range(struct vhost_umem *umem, u64 start, u64 size, u64 end, u64 userspace_addr, int perm) @@ -1844,8 +1909,7 @@ EXPORT_SYMBOL_GPL(vhost_log_write); static int vhost_update_used_flags(struct vhost_virtqueue *vq) { void __user *used; - if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), - &vq->used->flags) < 0) + if (vhost_put_used_flags(vq)) return -EFAULT; if (unlikely(vq->log_used)) { /* Make sure the flag is seen before log. */ @@ -1862,8 +1926,7 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq) static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event) { - if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), - vhost_avail_event(vq))) + if (vhost_put_avail_event(vq)) return -EFAULT; if (unlikely(vq->log_used)) { void __user *used; @@ -1899,7 +1962,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq) r = -EFAULT; goto err; } - r = vhost_get_used(vq, last_used_idx, &vq->used->idx); + r = vhost_get_used_idx(vq, &last_used_idx); if (r) { vq_err(vq, "Can't access used idx at %p\n", &vq->used->idx); @@ -2098,7 +2161,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, last_avail_idx = vq->last_avail_idx; if (vq->avail_idx == vq->last_avail_idx) { - if (unlikely(vhost_get_avail(vq, avail_idx, &vq->avail->idx))) { + if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) { vq_err(vq, "Failed to access avail idx at %p\n", &vq->avail->idx); return -EFAULT; @@ -2125,8 +2188,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* Grab the next descriptor number they're advertising, and increment * the index we've seen. */ - if (unlikely(vhost_get_avail(vq, ring_head, - &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { + if (unlikely(vhost_get_avail_head(vq, &ring_head, last_avail_idx))) { vq_err(vq, "Failed to read head: idx %d address %p\n", last_avail_idx, &vq->avail->ring[last_avail_idx % vq->num]); @@ -2161,8 +2223,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = vhost_copy_from_user(vq, &desc, vq->desc + i, - sizeof desc); + ret = vhost_get_desc(vq, &desc, i); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); @@ -2255,7 +2316,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, start = vq->last_used_idx & (vq->num - 1); used = vq->used->ring + start; - if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) { + if (vhost_put_used(vq, heads, start, count)) { vq_err(vq, "Failed to write used"); return -EFAULT; } @@ -2297,8 +2358,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, /* Make sure buffer is written before we update index. */ smp_wmb(); - if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), - &vq->used->idx)) { + if (vhost_put_used_idx(vq)) { vq_err(vq, "Failed to increment used idx"); return -EFAULT; } @@ -2331,7 +2391,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { __virtio16 flags; - if (vhost_get_avail(vq, flags, &vq->avail->flags)) { + if (vhost_get_avail_flags(vq, &flags)) { vq_err(vq, "Failed to get flags"); return true; } @@ -2345,7 +2405,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (unlikely(!v)) return true; - if (vhost_get_avail(vq, event, vhost_used_event(vq))) { + if (vhost_get_used_event(vq, &event)) { vq_err(vq, "Failed to get used event idx"); return true; } @@ -2390,7 +2450,7 @@ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (vq->avail_idx != vq->last_avail_idx) return false; - r = vhost_get_avail(vq, avail_idx, &vq->avail->idx); + r = vhost_get_avail_idx(vq, &avail_idx); if (unlikely(r)) return false; vq->avail_idx = vhost16_to_cpu(vq, avail_idx); @@ -2426,7 +2486,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) /* They could have slipped one in as we were doing that: make * sure it's written, then check again. */ smp_mb(); - r = vhost_get_avail(vq, avail_idx, &vq->avail->idx); + r = vhost_get_avail_idx(vq, &avail_idx); if (r) { vq_err(vq, "Failed to check avail idx at %p: %d\n", &vq->avail->idx, r); From patchwork Tue Apr 23 05:54:17 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10911953 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D975F922 for ; Tue, 23 Apr 2019 05:55:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CBD7D27D0C for ; Tue, 23 Apr 2019 05:55:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BFACC28113; Tue, 23 Apr 2019 05:55:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 70E3027D0C for ; Tue, 23 Apr 2019 05:55:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726257AbfDWFyx (ORCPT ); Tue, 23 Apr 2019 01:54:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40186 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726262AbfDWFyx (ORCPT ); Tue, 23 Apr 2019 01:54:53 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2483BF74AC; Tue, 23 Apr 2019 05:54:53 +0000 (UTC) Received: from hp-dl380pg8-01.lab.eng.pek2.redhat.com (hp-dl380pg8-01.lab.eng.pek2.redhat.com [10.73.8.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id BD99D1A8F6; Tue, 23 Apr 2019 05:54:43 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterx@redhat.com, aarcange@redhat.com, James.Bottomley@hansenpartnership.com, hch@infradead.org, davem@davemloft.net, jglisse@redhat.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, christophe.de.dinechin@gmail.com, jrdr.linux@gmail.com Subject: [RFC PATCH V3 3/6] vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch() Date: Tue, 23 Apr 2019 01:54:17 -0400 Message-Id: <20190423055420.26408-4-jasowang@redhat.com> In-Reply-To: <20190423055420.26408-1-jasowang@redhat.com> References: <20190423055420.26408-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 23 Apr 2019 05:54:53 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Rename the function to be more accurate since it actually tries to prefetch vq metadata address in IOTLB. And this will be used by following patch to prefetch metadata virtual addresses. Signed-off-by: Jason Wang --- drivers/vhost/net.c | 4 ++-- drivers/vhost/vhost.c | 4 ++-- drivers/vhost/vhost.h | 2 +- 3 files changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index df51a35cf537..bf55f995ebae 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -971,7 +971,7 @@ static void handle_tx(struct vhost_net *net) if (!sock) goto out; - if (!vq_iotlb_prefetch(vq)) + if (!vq_meta_prefetch(vq)) goto out; vhost_disable_notify(&net->dev, vq); @@ -1140,7 +1140,7 @@ static void handle_rx(struct vhost_net *net) if (!sock) goto out; - if (!vq_iotlb_prefetch(vq)) + if (!vq_meta_prefetch(vq)) goto out; vhost_disable_notify(&net->dev, vq); diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 7335f2275ed3..bff4d586871d 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1313,7 +1313,7 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq, return true; } -int vq_iotlb_prefetch(struct vhost_virtqueue *vq) +int vq_meta_prefetch(struct vhost_virtqueue *vq) { size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; unsigned int num = vq->num; @@ -1332,7 +1332,7 @@ int vq_iotlb_prefetch(struct vhost_virtqueue *vq) num * sizeof(*vq->used->ring) + s, VHOST_ADDR_USED); } -EXPORT_SYMBOL_GPL(vq_iotlb_prefetch); +EXPORT_SYMBOL_GPL(vq_meta_prefetch); /* Can we log writes? */ /* Caller should have device mutex but not vq mutex */ diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 9490e7ddb340..7a7fc001265f 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -209,7 +209,7 @@ bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *); int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, unsigned int log_num, u64 len, struct iovec *iov, int count); -int vq_iotlb_prefetch(struct vhost_virtqueue *vq); +int vq_meta_prefetch(struct vhost_virtqueue *vq); struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type); void vhost_enqueue_msg(struct vhost_dev *dev, From patchwork Tue Apr 23 05:54:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10911957 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0B768112C for ; Tue, 23 Apr 2019 05:55:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F139C27D29 for ; Tue, 23 Apr 2019 05:55:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E4DB3281C3; Tue, 23 Apr 2019 05:55:07 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 851BD27D29 for ; Tue, 23 Apr 2019 05:55:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726325AbfDWFy7 (ORCPT ); Tue, 23 Apr 2019 01:54:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:16337 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725888AbfDWFy7 (ORCPT ); Tue, 23 Apr 2019 01:54:59 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9D8D63087925; Tue, 23 Apr 2019 05:54:58 +0000 (UTC) Received: from hp-dl380pg8-01.lab.eng.pek2.redhat.com (hp-dl380pg8-01.lab.eng.pek2.redhat.com [10.73.8.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9ECD3261D1; Tue, 23 Apr 2019 05:54:53 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterx@redhat.com, aarcange@redhat.com, James.Bottomley@hansenpartnership.com, hch@infradead.org, davem@davemloft.net, jglisse@redhat.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, christophe.de.dinechin@gmail.com, jrdr.linux@gmail.com Subject: [RFC PATCH V3 4/6] vhost: introduce helpers to get the size of metadata area Date: Tue, 23 Apr 2019 01:54:18 -0400 Message-Id: <20190423055420.26408-5-jasowang@redhat.com> In-Reply-To: <20190423055420.26408-1-jasowang@redhat.com> References: <20190423055420.26408-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Tue, 23 Apr 2019 05:54:58 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP To avoid code duplication since it will be used by kernel VA prefetching. Signed-off-by: Jason Wang --- drivers/vhost/vhost.c | 51 ++++++++++++++++++++++++++++--------------- 1 file changed, 33 insertions(+), 18 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index bff4d586871d..f3f86c3ed659 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -413,6 +413,32 @@ static void vhost_dev_free_iovecs(struct vhost_dev *dev) vhost_vq_free_iovecs(dev->vqs[i]); } +static size_t vhost_get_avail_size(struct vhost_virtqueue *vq, + unsigned int num) +{ + size_t event __maybe_unused = + vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + + return sizeof(*vq->avail) + + sizeof(*vq->avail->ring) * num + event; +} + +static size_t vhost_get_used_size(struct vhost_virtqueue *vq, + unsigned int num) +{ + size_t event __maybe_unused = + vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + + return sizeof(*vq->used) + + sizeof(*vq->used->ring) * num + event; +} + +static size_t vhost_get_desc_size(struct vhost_virtqueue *vq, + unsigned int num) +{ + return sizeof(*vq->desc) * num; +} + void vhost_dev_init(struct vhost_dev *dev, struct vhost_virtqueue **vqs, int nvqs, int iov_limit) { @@ -1257,13 +1283,9 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, struct vring_used __user *used) { - size_t s __maybe_unused = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; - - return access_ok(desc, num * sizeof *desc) && - access_ok(avail, - sizeof *avail + num * sizeof *avail->ring + s) && - access_ok(used, - sizeof *used + num * sizeof *used->ring + s); + return access_ok(desc, vhost_get_desc_size(vq, num)) && + access_ok(avail, vhost_get_avail_size(vq, num)) && + access_ok(used, vhost_get_used_size(vq, num)); } static void vhost_vq_meta_update(struct vhost_virtqueue *vq, @@ -1315,22 +1337,18 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq, int vq_meta_prefetch(struct vhost_virtqueue *vq) { - size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; unsigned int num = vq->num; if (!vq->iotlb) return 1; return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc, - num * sizeof(*vq->desc), VHOST_ADDR_DESC) && + vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) && iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->avail, - sizeof *vq->avail + - num * sizeof(*vq->avail->ring) + s, + vhost_get_avail_size(vq, num), VHOST_ADDR_AVAIL) && iotlb_access_ok(vq, VHOST_ACCESS_WO, (u64)(uintptr_t)vq->used, - sizeof *vq->used + - num * sizeof(*vq->used->ring) + s, - VHOST_ADDR_USED); + vhost_get_used_size(vq, num), VHOST_ADDR_USED); } EXPORT_SYMBOL_GPL(vq_meta_prefetch); @@ -1347,13 +1365,10 @@ EXPORT_SYMBOL_GPL(vhost_log_access_ok); static bool vq_log_access_ok(struct vhost_virtqueue *vq, void __user *log_base) { - size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; - return vq_memory_access_ok(log_base, vq->umem, vhost_has_feature(vq, VHOST_F_LOG_ALL)) && (!vq->log_used || log_access_ok(log_base, vq->log_addr, - sizeof *vq->used + - vq->num * sizeof *vq->used->ring + s)); + vhost_get_used_size(vq, vq->num))); } /* Can we start vq? */ From patchwork Tue Apr 23 05:54:19 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10911963 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E120D112C for ; Tue, 23 Apr 2019 05:55:13 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D1F7727D0C for ; Tue, 23 Apr 2019 05:55:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C429028113; Tue, 23 Apr 2019 05:55:13 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3A8D027D0C for ; Tue, 23 Apr 2019 05:55:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726382AbfDWFzH (ORCPT ); Tue, 23 Apr 2019 01:55:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33864 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726358AbfDWFzG (ORCPT ); Tue, 23 Apr 2019 01:55:06 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BFAE030917AD; Tue, 23 Apr 2019 05:55:05 +0000 (UTC) Received: from hp-dl380pg8-01.lab.eng.pek2.redhat.com (hp-dl380pg8-01.lab.eng.pek2.redhat.com [10.73.8.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 25C64261D3; Tue, 23 Apr 2019 05:54:58 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterx@redhat.com, aarcange@redhat.com, James.Bottomley@hansenpartnership.com, hch@infradead.org, davem@davemloft.net, jglisse@redhat.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, christophe.de.dinechin@gmail.com, jrdr.linux@gmail.com Subject: [RFC PATCH V3 5/6] vhost: factor out setting vring addr and num Date: Tue, 23 Apr 2019 01:54:19 -0400 Message-Id: <20190423055420.26408-6-jasowang@redhat.com> In-Reply-To: <20190423055420.26408-1-jasowang@redhat.com> References: <20190423055420.26408-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Tue, 23 Apr 2019 05:55:05 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Factoring vring address and num setting which needs special care for accelerating vq metadata accessing. Signed-off-by: Jason Wang --- drivers/vhost/vhost.c | 177 ++++++++++++++++++++++++------------------ 1 file changed, 103 insertions(+), 74 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index f3f86c3ed659..c2362ed5839e 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1468,6 +1468,104 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) return -EFAULT; } +static long vhost_vring_set_num(struct vhost_dev *d, + struct vhost_virtqueue *vq, + void __user *argp) +{ + struct vhost_vring_state s; + + /* Resizing ring with an active backend? + * You don't want to do that. */ + if (vq->private_data) + return -EBUSY; + + if (copy_from_user(&s, argp, sizeof s)) + return -EFAULT; + + if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) + return -EINVAL; + vq->num = s.num; + + return 0; +} + +static long vhost_vring_set_addr(struct vhost_dev *d, + struct vhost_virtqueue *vq, + void __user *argp) +{ + struct vhost_vring_addr a; + + if (copy_from_user(&a, argp, sizeof a)) + return -EFAULT; + if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) + return -EOPNOTSUPP; + + /* For 32bit, verify that the top 32bits of the user + data are set to zero. */ + if ((u64)(unsigned long)a.desc_user_addr != a.desc_user_addr || + (u64)(unsigned long)a.used_user_addr != a.used_user_addr || + (u64)(unsigned long)a.avail_user_addr != a.avail_user_addr) + return -EFAULT; + + /* Make sure it's safe to cast pointers to vring types. */ + BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE); + BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE); + if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) || + (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) || + (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) + return -EINVAL; + + /* We only verify access here if backend is configured. + * If it is not, we don't as size might not have been setup. + * We will verify when backend is configured. */ + if (vq->private_data) { + if (!vq_access_ok(vq, vq->num, + (void __user *)(unsigned long)a.desc_user_addr, + (void __user *)(unsigned long)a.avail_user_addr, + (void __user *)(unsigned long)a.used_user_addr)) + return -EINVAL; + + /* Also validate log access for used ring if enabled. */ + if ((a.flags & (0x1 << VHOST_VRING_F_LOG)) && + !log_access_ok(vq->log_base, a.log_guest_addr, + sizeof *vq->used + + vq->num * sizeof *vq->used->ring)) + return -EINVAL; + } + + vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG)); + vq->desc = (void __user *)(unsigned long)a.desc_user_addr; + vq->avail = (void __user *)(unsigned long)a.avail_user_addr; + vq->log_addr = a.log_guest_addr; + vq->used = (void __user *)(unsigned long)a.used_user_addr; + + return 0; +} + +static long vhost_vring_set_num_addr(struct vhost_dev *d, + struct vhost_virtqueue *vq, + unsigned int ioctl, + void __user *argp) +{ + long r; + + mutex_lock(&vq->mutex); + + switch (ioctl) { + case VHOST_SET_VRING_NUM: + r = vhost_vring_set_num(d, vq, argp); + break; + case VHOST_SET_VRING_ADDR: + r = vhost_vring_set_addr(d, vq, argp); + break; + default: + BUG(); + } + + mutex_unlock(&vq->mutex); + + return r; +} long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) { struct file *eventfp, *filep = NULL; @@ -1477,7 +1575,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg struct vhost_virtqueue *vq; struct vhost_vring_state s; struct vhost_vring_file f; - struct vhost_vring_addr a; u32 idx; long r; @@ -1490,26 +1587,14 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg idx = array_index_nospec(idx, d->nvqs); vq = d->vqs[idx]; + if (ioctl == VHOST_SET_VRING_NUM || + ioctl == VHOST_SET_VRING_ADDR) { + return vhost_vring_set_num_addr(d, vq, ioctl, argp); + } + mutex_lock(&vq->mutex); switch (ioctl) { - case VHOST_SET_VRING_NUM: - /* Resizing ring with an active backend? - * You don't want to do that. */ - if (vq->private_data) { - r = -EBUSY; - break; - } - if (copy_from_user(&s, argp, sizeof s)) { - r = -EFAULT; - break; - } - if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) { - r = -EINVAL; - break; - } - vq->num = s.num; - break; case VHOST_SET_VRING_BASE: /* Moving base with an active backend? * You don't want to do that. */ @@ -1535,62 +1620,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg if (copy_to_user(argp, &s, sizeof s)) r = -EFAULT; break; - case VHOST_SET_VRING_ADDR: - if (copy_from_user(&a, argp, sizeof a)) { - r = -EFAULT; - break; - } - if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) { - r = -EOPNOTSUPP; - break; - } - /* For 32bit, verify that the top 32bits of the user - data are set to zero. */ - if ((u64)(unsigned long)a.desc_user_addr != a.desc_user_addr || - (u64)(unsigned long)a.used_user_addr != a.used_user_addr || - (u64)(unsigned long)a.avail_user_addr != a.avail_user_addr) { - r = -EFAULT; - break; - } - - /* Make sure it's safe to cast pointers to vring types. */ - BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE); - BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE); - if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) || - (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) || - (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) { - r = -EINVAL; - break; - } - - /* We only verify access here if backend is configured. - * If it is not, we don't as size might not have been setup. - * We will verify when backend is configured. */ - if (vq->private_data) { - if (!vq_access_ok(vq, vq->num, - (void __user *)(unsigned long)a.desc_user_addr, - (void __user *)(unsigned long)a.avail_user_addr, - (void __user *)(unsigned long)a.used_user_addr)) { - r = -EINVAL; - break; - } - - /* Also validate log access for used ring if enabled. */ - if ((a.flags & (0x1 << VHOST_VRING_F_LOG)) && - !log_access_ok(vq->log_base, a.log_guest_addr, - sizeof *vq->used + - vq->num * sizeof *vq->used->ring)) { - r = -EINVAL; - break; - } - } - - vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG)); - vq->desc = (void __user *)(unsigned long)a.desc_user_addr; - vq->avail = (void __user *)(unsigned long)a.avail_user_addr; - vq->log_addr = a.log_guest_addr; - vq->used = (void __user *)(unsigned long)a.used_user_addr; - break; case VHOST_SET_VRING_KICK: if (copy_from_user(&f, argp, sizeof f)) { r = -EFAULT; From patchwork Tue Apr 23 05:54:20 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10911969 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 152E6922 for ; Tue, 23 Apr 2019 05:55:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 05A1128733 for ; Tue, 23 Apr 2019 05:55:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ED9DC28738; Tue, 23 Apr 2019 05:55:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C35A528733 for ; Tue, 23 Apr 2019 05:55:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726423AbfDWFzR (ORCPT ); Tue, 23 Apr 2019 01:55:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51218 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726410AbfDWFzR (ORCPT ); Tue, 23 Apr 2019 01:55:17 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1E2E830BC654; Tue, 23 Apr 2019 05:55:16 +0000 (UTC) Received: from hp-dl380pg8-01.lab.eng.pek2.redhat.com (hp-dl380pg8-01.lab.eng.pek2.redhat.com [10.73.8.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 79EB9261D9; Tue, 23 Apr 2019 05:55:06 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterx@redhat.com, aarcange@redhat.com, James.Bottomley@hansenpartnership.com, hch@infradead.org, davem@davemloft.net, jglisse@redhat.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, christophe.de.dinechin@gmail.com, jrdr.linux@gmail.com Subject: [RFC PATCH V3 6/6] vhost: access vq metadata through kernel virtual address Date: Tue, 23 Apr 2019 01:54:20 -0400 Message-Id: <20190423055420.26408-7-jasowang@redhat.com> In-Reply-To: <20190423055420.26408-1-jasowang@redhat.com> References: <20190423055420.26408-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Tue, 23 Apr 2019 05:55:16 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP It was noticed that the copy_to/from_user() friends that was used to access virtqueue metdata tends to be very expensive for dataplane implementation like vhost since it involves lots of software checks, speculation barriers, hardware feature toggling (e.g SMAP). The extra cost will be more obvious when transferring small packets since the time spent on metadata accessing become more significant. This patch tries to eliminate those overheads by accessing them through direct mapping of those pages. Invalidation callbacks is implemented for co-operation with general VM management (swap, KSM, THP or NUMA balancing). We will try to get the direct mapping of vq metadata before each round of packet processing if it doesn't exist. If we fail, we will simplely fallback to copy_to/from_user() friends. This invalidation and direct mapping access are synchronized through spinlock and RCU. All matedata accessing through direct map is protected by RCU, and the setup or invalidation are done under spinlock. This method might does not work for high mem page which requires temporary mapping so we just fallback to normal copy_to/from_user() and may not for arch that has virtual tagged cache since extra cache flushing is needed to eliminate the alias. This will result complex logic and bad performance. For those archs, this patch simply go for copy_to/from_user() friends. This is done by ruling out kernel mapping codes through ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE. Note that this is only done when device IOTLB is not enabled. We could use similar method to optimize IOTLB in the future. Tests shows at most about 23% improvement on TX PPS when using virtio-user + vhost_net + xdp1 + TAP on 2.6GHz Broadwell: SMAP on | SMAP off Before: 5.2Mpps | 7.1Mpps After: 6.4Mpps | 8.2Mpps Cc: Andrea Arcangeli Cc: James Bottomley Cc: Christoph Hellwig Cc: David Miller Cc: Jerome Glisse Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-parisc@vger.kernel.org Signed-off-by: Jason Wang --- drivers/vhost/vhost.c | 517 +++++++++++++++++++++++++++++++++++++++++- drivers/vhost/vhost.h | 32 +++ 2 files changed, 546 insertions(+), 3 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index c2362ed5839e..a9fe04f0016a 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -299,6 +299,49 @@ static void vhost_vq_meta_reset(struct vhost_dev *d) __vhost_vq_meta_reset(d->vqs[i]); } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 +static void vhost_map_unprefetch(struct vhost_map *map) +{ + kfree(map->pages); + map->pages = NULL; + map->npages = 0; + map->addr = NULL; +} + +static void vhost_uninit_vq_maps(struct vhost_virtqueue *vq) +{ + struct vhost_map *map[VHOST_NUM_ADDRS]; + int i; + + spin_lock(&vq->mmu_lock); + for (i = 0; i < VHOST_NUM_ADDRS; i++) { + map[i] = rcu_dereference_protected(vq->maps[i], + lockdep_is_held(&vq->mmu_lock)); + if (map[i]) + rcu_assign_pointer(vq->maps[i], NULL); + } + spin_unlock(&vq->mmu_lock); + + synchronize_rcu(); + + for (i = 0; i < VHOST_NUM_ADDRS; i++) + if (map[i]) + vhost_map_unprefetch(map[i]); + +} +#endif + +static void vhost_reset_vq_maps(struct vhost_virtqueue *vq) +{ +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + int i; + + vhost_uninit_vq_maps(vq); + for (i = 0; i < VHOST_NUM_ADDRS; i++) + vq->uaddrs[i].size = 0; +#endif +} + static void vhost_vq_reset(struct vhost_dev *dev, struct vhost_virtqueue *vq) { @@ -327,7 +370,9 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->busyloop_timeout = 0; vq->umem = NULL; vq->iotlb = NULL; + vq->invalidate_count = 0; __vhost_vq_meta_reset(vq); + vhost_reset_vq_maps(vq); } static int vhost_worker(void *data) @@ -439,6 +484,123 @@ static size_t vhost_get_desc_size(struct vhost_virtqueue *vq, return sizeof(*vq->desc) * num; } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 +static bool vhost_map_range_overlap(struct vhost_uaddr *uaddr, + unsigned long start, + unsigned long end) +{ + if (unlikely(!uaddr->size)) + return false; + + return !(end < uaddr->uaddr || start > uaddr->uaddr - 1 + uaddr->size); +} + +static void vhost_invalidate_vq_start(struct vhost_virtqueue *vq, + int index, + unsigned long start, + unsigned long end) +{ + struct vhost_uaddr *uaddr = &vq->uaddrs[index]; + struct vhost_map *map; + int i; + + if (!vhost_map_range_overlap(uaddr, start, end)) + return; + + spin_lock(&vq->mmu_lock); + ++vq->invalidate_count; + + map = rcu_dereference_protected(vq->maps[index], + lockdep_is_held(&vq->mmu_lock)); + if (map) { + if (uaddr->write) { + for (i = 0; i < map->npages; i++) + set_page_dirty(map->pages[i]); + } + rcu_assign_pointer(vq->maps[index], NULL); + } + spin_unlock(&vq->mmu_lock); + + if (map) { + synchronize_rcu(); + vhost_map_unprefetch(map); + } +} + +static void vhost_invalidate_vq_end(struct vhost_virtqueue *vq, + int index, + unsigned long start, + unsigned long end) +{ + if (!vhost_map_range_overlap(&vq->uaddrs[index], start, end)) + return; + + spin_lock(&vq->mmu_lock); + --vq->invalidate_count; + spin_unlock(&vq->mmu_lock); +} + +static int vhost_invalidate_range_start(struct mmu_notifier *mn, + const struct mmu_notifier_range *range) +{ + struct vhost_dev *dev = container_of(mn, struct vhost_dev, + mmu_notifier); + int i, j; + + if (!range->blockable) + return -EAGAIN; + + for (i = 0; i < dev->nvqs; i++) { + struct vhost_virtqueue *vq = dev->vqs[i]; + + for (j = 0; j < VHOST_NUM_ADDRS; j++) + vhost_invalidate_vq_start(vq, j, + range->start, + range->end); + } + + return 0; +} + +static void vhost_invalidate_range_end(struct mmu_notifier *mn, + const struct mmu_notifier_range *range) +{ + struct vhost_dev *dev = container_of(mn, struct vhost_dev, + mmu_notifier); + int i, j; + + for (i = 0; i < dev->nvqs; i++) { + struct vhost_virtqueue *vq = dev->vqs[i]; + + for (j = 0; j < VHOST_NUM_ADDRS; j++) + vhost_invalidate_vq_end(vq, j, + range->start, + range->end); + } +} + +static const struct mmu_notifier_ops vhost_mmu_notifier_ops = { + .invalidate_range_start = vhost_invalidate_range_start, + .invalidate_range_end = vhost_invalidate_range_end, +}; +#endif + +static void vhost_init_maps(struct vhost_dev *dev) +{ +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_virtqueue *vq; + int i, j; + + dev->mmu_notifier.ops = &vhost_mmu_notifier_ops; + + for (i = 0; i < dev->nvqs; ++i) { + vq = dev->vqs[i]; + for (j = 0; j < VHOST_NUM_ADDRS; j++) + RCU_INIT_POINTER(vq->maps[j], NULL); + } +#endif +} + void vhost_dev_init(struct vhost_dev *dev, struct vhost_virtqueue **vqs, int nvqs, int iov_limit) { @@ -459,7 +621,7 @@ void vhost_dev_init(struct vhost_dev *dev, INIT_LIST_HEAD(&dev->read_list); INIT_LIST_HEAD(&dev->pending_list); spin_lock_init(&dev->iotlb_lock); - + vhost_init_maps(dev); for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; @@ -468,6 +630,7 @@ void vhost_dev_init(struct vhost_dev *dev, vq->heads = NULL; vq->dev = dev; mutex_init(&vq->mutex); + spin_lock_init(&vq->mmu_lock); vhost_vq_reset(dev, vq); if (vq->handle_kick) vhost_poll_init(&vq->poll, vq->handle_kick, @@ -547,7 +710,18 @@ long vhost_dev_set_owner(struct vhost_dev *dev) if (err) goto err_cgroup; +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + err = mmu_notifier_register(&dev->mmu_notifier, dev->mm); + if (err) + goto err_mmu_notifier; +#endif + return 0; + +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 +err_mmu_notifier: + vhost_dev_free_iovecs(dev); +#endif err_cgroup: kthread_stop(worker); dev->worker = NULL; @@ -638,6 +812,107 @@ static void vhost_clear_msg(struct vhost_dev *dev) spin_unlock(&dev->iotlb_lock); } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 +static void vhost_setup_uaddr(struct vhost_virtqueue *vq, + int index, unsigned long uaddr, + size_t size, bool write) +{ + struct vhost_uaddr *addr = &vq->uaddrs[index]; + + addr->uaddr = uaddr; + addr->size = size; + addr->write = write; +} + +static void vhost_setup_vq_uaddr(struct vhost_virtqueue *vq) +{ + vhost_setup_uaddr(vq, VHOST_ADDR_DESC, + (unsigned long)vq->desc, + vhost_get_desc_size(vq, vq->num), + false); + vhost_setup_uaddr(vq, VHOST_ADDR_AVAIL, + (unsigned long)vq->avail, + vhost_get_avail_size(vq, vq->num), + false); + vhost_setup_uaddr(vq, VHOST_ADDR_USED, + (unsigned long)vq->used, + vhost_get_used_size(vq, vq->num), + true); +} + +static int vhost_map_prefetch(struct vhost_virtqueue *vq, + int index) +{ + struct vhost_map *map; + struct vhost_uaddr *uaddr = &vq->uaddrs[index]; + struct page **pages; + int npages = DIV_ROUND_UP(uaddr->size, PAGE_SIZE); + int npinned; + void *vaddr, *v; + int err; + int i; + + spin_lock(&vq->mmu_lock); + + err = -EFAULT; + if (vq->invalidate_count) + goto err; + + err = -ENOMEM; + map = kmalloc(sizeof(*map), GFP_ATOMIC); + if (!map) + goto err; + + pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); + if (!pages) + goto err_pages; + + err = EFAULT; + npinned = __get_user_pages_fast(uaddr->uaddr, npages, + uaddr->write, pages); + if (npinned > 0) + release_pages(pages, npinned); + if (npinned != npages) + goto err_gup; + + for (i = 0; i < npinned; i++) + if (PageHighMem(pages[i])) + goto err_gup; + + vaddr = v = page_address(pages[0]); + + /* For simplicity, fallback to userspace address if VA is not + * contigious. + */ + for (i = 1; i < npinned; i++) { + v += PAGE_SIZE; + if (v != page_address(pages[i])) + goto err_gup; + } + + map->addr = vaddr + (uaddr->uaddr & (PAGE_SIZE - 1)); + map->npages = npages; + map->pages = pages; + + rcu_assign_pointer(vq->maps[index], map); + /* No need for a synchronize_rcu(). This function should be + * called by dev->worker so we are serialized with all + * readers. + */ + spin_unlock(&vq->mmu_lock); + + return 0; + +err_gup: + kfree(pages); +err_pages: + kfree(map); +err: + spin_unlock(&vq->mmu_lock); + return err; +} +#endif + void vhost_dev_cleanup(struct vhost_dev *dev) { int i; @@ -667,8 +942,16 @@ void vhost_dev_cleanup(struct vhost_dev *dev) kthread_stop(dev->worker); dev->worker = NULL; } - if (dev->mm) + if (dev->mm) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + mmu_notifier_unregister(&dev->mmu_notifier, dev->mm); +#endif mmput(dev->mm); + } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + for (i = 0; i < dev->nvqs; i++) + vhost_uninit_vq_maps(dev->vqs[i]); +#endif dev->mm = NULL; } EXPORT_SYMBOL_GPL(vhost_dev_cleanup); @@ -897,6 +1180,26 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq, static inline int vhost_put_avail_event(struct vhost_virtqueue *vq) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + *((__virtio16 *)&used->ring[vq->num]) = + cpu_to_vhost16(vq, vq->avail_idx); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), vhost_avail_event(vq)); } @@ -905,6 +1208,27 @@ static inline int vhost_put_used(struct vhost_virtqueue *vq, struct vring_used_elem *head, int idx, int count) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_used *used; + size_t size; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + size = count * sizeof(*head); + memcpy(used->ring + idx, head, size); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_copy_to_user(vq, vq->used->ring + idx, head, count * sizeof(*head)); } @@ -912,6 +1236,25 @@ static inline int vhost_put_used(struct vhost_virtqueue *vq, static inline int vhost_put_used_flags(struct vhost_virtqueue *vq) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + used->flags = cpu_to_vhost16(vq, vq->used_flags); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), &vq->used->flags); } @@ -919,6 +1262,25 @@ static inline int vhost_put_used_flags(struct vhost_virtqueue *vq) static inline int vhost_put_used_idx(struct vhost_virtqueue *vq) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + used->idx = cpu_to_vhost16(vq, vq->last_used_idx); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), &vq->used->idx); } @@ -964,12 +1326,50 @@ static void vhost_dev_unlock_vqs(struct vhost_dev *d) static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq, __virtio16 *idx) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *idx = avail->idx; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_get_avail(vq, *idx, &vq->avail->idx); } static inline int vhost_get_avail_head(struct vhost_virtqueue *vq, __virtio16 *head, int idx) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *head = avail->ring[idx & (vq->num - 1)]; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_get_avail(vq, *head, &vq->avail->ring[idx & (vq->num - 1)]); } @@ -977,24 +1377,98 @@ static inline int vhost_get_avail_head(struct vhost_virtqueue *vq, static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq, __virtio16 *flags) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *flags = avail->flags; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_get_avail(vq, *flags, &vq->avail->flags); } static inline int vhost_get_used_event(struct vhost_virtqueue *vq, __virtio16 *event) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *event = (__virtio16)avail->ring[vq->num]; + rcu_read_unlock(); + return 0; + } + rcu_read_unlock(); + } +#endif + return vhost_get_avail(vq, *event, vhost_used_event(vq)); } static inline int vhost_get_used_idx(struct vhost_virtqueue *vq, __virtio16 *idx) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + *idx = used->idx; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_get_used(vq, *idx, &vq->used->idx); } static inline int vhost_get_desc(struct vhost_virtqueue *vq, struct vring_desc *desc, int idx) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + struct vhost_map *map; + struct vring_desc *d; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_DESC]); + if (likely(map)) { + d = map->addr; + *desc = *(d + idx); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc)); } @@ -1335,12 +1809,32 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq, return true; } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 +static void vhost_vq_map_prefetch(struct vhost_virtqueue *vq) +{ + struct vhost_map __rcu *map; + int i; + + for (i = 0; i < VHOST_NUM_ADDRS; i++) { + rcu_read_lock(); + map = rcu_dereference(vq->maps[i]); + rcu_read_unlock(); + if (unlikely(!map)) + vhost_map_prefetch(vq, i); + } +} +#endif + int vq_meta_prefetch(struct vhost_virtqueue *vq) { unsigned int num = vq->num; - if (!vq->iotlb) + if (!vq->iotlb) { +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + vhost_vq_map_prefetch(vq); +#endif return 1; + } return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc, vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) && @@ -1551,6 +2045,16 @@ static long vhost_vring_set_num_addr(struct vhost_dev *d, mutex_lock(&vq->mutex); +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + /* Unregister MMU notifer to allow invalidation callback + * can access vq->uaddrs[] without holding a lock. + */ + if (d->mm) + mmu_notifier_unregister(&d->mmu_notifier, d->mm); + + vhost_uninit_vq_maps(vq); +#endif + switch (ioctl) { case VHOST_SET_VRING_NUM: r = vhost_vring_set_num(d, vq, argp); @@ -1562,6 +2066,13 @@ static long vhost_vring_set_num_addr(struct vhost_dev *d, BUG(); } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + vhost_setup_vq_uaddr(vq); + + if (d->mm) + mmu_notifier_register(&d->mmu_notifier, d->mm); +#endif + mutex_unlock(&vq->mutex); return r; diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 7a7fc001265f..f33208b55875 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -12,6 +12,9 @@ #include #include #include +#include +#include +#include struct vhost_work; typedef void (*vhost_work_fn_t)(struct vhost_work *work); @@ -80,6 +83,18 @@ enum vhost_uaddr_type { VHOST_NUM_ADDRS = 3, }; +struct vhost_map { + int npages; + void *addr; + struct page **pages; +}; + +struct vhost_uaddr { + unsigned long uaddr; + size_t size; + bool write; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -90,7 +105,21 @@ struct vhost_virtqueue { struct vring_desc __user *desc; struct vring_avail __user *avail; struct vring_used __user *used; + +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 + /* read by memory accessors, modified by meta data + * prefetching, MMU notifier and vring ioctl(). + * Synchonrized through mmu_lock (writers) and RCU (writers + * and readers). + */ + struct vhost_map __rcu *maps[VHOST_NUM_ADDRS]; + /* read by MMU notifier, write by vring ioctl(), synchronized + * through register/unregister MMU notifier. + */ + struct vhost_uaddr uaddrs[VHOST_NUM_ADDRS]; +#endif const struct vhost_umem_node *meta_iotlb[VHOST_NUM_ADDRS]; + struct file *kick; struct eventfd_ctx *call_ctx; struct eventfd_ctx *error_ctx; @@ -145,6 +174,8 @@ struct vhost_virtqueue { bool user_be; #endif u32 busyloop_timeout; + spinlock_t mmu_lock; + int invalidate_count; }; struct vhost_msg_node { @@ -158,6 +189,7 @@ struct vhost_msg_node { struct vhost_dev { struct mm_struct *mm; + struct mmu_notifier mmu_notifier; struct mutex mutex; struct vhost_virtqueue **vqs; int nvqs;