From patchwork Fri Dec 28 07:55:36 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10744209 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 0BD1F13B5 for ; Fri, 28 Dec 2018 07:56:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F25B628BB0 for ; Fri, 28 Dec 2018 07:56:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E708E28BFB; Fri, 28 Dec 2018 07:56:15 +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 55D3E28BB0 for ; Fri, 28 Dec 2018 07:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731848AbeL1Hz4 (ORCPT ); Fri, 28 Dec 2018 02:55:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49802 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731819AbeL1Hzy (ORCPT ); Fri, 28 Dec 2018 02:55:54 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 55F96C05D40E; Fri, 28 Dec 2018 07:55:53 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-196.pek2.redhat.com [10.72.12.196]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1E1C95D9CC; Fri, 28 Dec 2018 07:55:48 +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 Subject: [RFC PATCH V2 2/3] vhost: fine grain userspace memory accessors Date: Fri, 28 Dec 2018 15:55:36 +0800 Message-Id: <20181228075537.21402-3-jasowang@redhat.com> In-Reply-To: <20181228075537.21402-1-jasowang@redhat.com> References: <20181228075537.21402-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Fri, 28 Dec 2018 07:55:53 +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 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 f179b5ee14c4..337ce6f5a098 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -868,6 +868,34 @@ 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; \ @@ -906,6 +934,43 @@ 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) @@ -1761,8 +1826,7 @@ 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. */ @@ -1780,8 +1844,7 @@ 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; @@ -1818,7 +1881,7 @@ 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); @@ -2017,7 +2080,7 @@ 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; @@ -2044,8 +2107,7 @@ 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]); @@ -2080,8 +2142,7 @@ 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); @@ -2174,7 +2235,7 @@ 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; } @@ -2218,8 +2279,7 @@ 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; } @@ -2253,7 +2313,7 @@ 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; } @@ -2267,7 +2327,7 @@ 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; } @@ -2312,7 +2372,7 @@ 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); @@ -2348,7 +2408,7 @@ 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);