From patchwork Sun Jun 7 14:11:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217955 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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 AE5B9C433E0 for ; Sun, 7 Jun 2020 14:13:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 768EF2067B for ; Sun, 7 Jun 2020 14:13:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="IB38MuSE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726692AbgFGOLh (ORCPT ); Sun, 7 Jun 2020 10:11:37 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:42185 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726566AbgFGOLb (ORCPT ); Sun, 7 Jun 2020 10:11:31 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591539088; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rBDX8velINEAtqraPcdgZxMSF664hQ9MVgqoZQFcfGw=; b=IB38MuSEWDqKRM50jCvbbuWuPxslUxiq1eqoJP0ByyNg4GqbK1xVbbPqWsAfL8z+bmmaDI qBOet6RPmh3NAB/ArKr14yjXQd+ojNjKfK2rHaegyhU3+Qehgn6U1FsuAYvuXIKZGyxmHy sZkA3WRETOoUCzbqStCXR9lemH0w5b8= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-86-Mtua3KNiOSGxLLYQU2O_AA-1; Sun, 07 Jun 2020 10:11:26 -0400 X-MC-Unique: Mtua3KNiOSGxLLYQU2O_AA-1 Received: by mail-wm1-f71.google.com with SMTP id h25so4804256wmb.0 for ; Sun, 07 Jun 2020 07:11:26 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=rBDX8velINEAtqraPcdgZxMSF664hQ9MVgqoZQFcfGw=; b=beDEYV5e3WikovXB/zVCBgdIXKwjUXMDq/oz11dtAC4WBzS1DS9GzseeWQCdMHz1k7 OSX4JlUpbpjQJrCr7I8F6cLY5lFwVp8dcKVqN2Pfnl2U4uxWcmI+3vByuAwB3bq7AnWp vOpvWdMQ8u+7Mxy7MTxyXMNvHlIRJuvSDLKQMELOA2JFKZFKJIdSx1P4u9O+roPvQSvU IxArya6NNc2kEDmvcjvQpR1w//8ePCg9QEX1QP4YThM5WaS5oJ55lgdqLmuC2RjHsKeO BWmsZdoSEZhRw8v6+R6/HIVNmAHTA/5mIP3nRNxODEPrJY4Vpd8G0dN/AiHcOAVfS8iI Oy7A== X-Gm-Message-State: AOAM530nGgYt/OCYDqV5eES0E0U0l+aARozwStnqczWJkNhfHAhb7NnS eBSl4tHBuBkJqdYJAVIQCfuASmrsVhZpCf/GTql4BRyUxbN0eQpfG5onHjXnWKPU3xF+XLN4lNq yJvB7VuxtlIlJlDU3 X-Received: by 2002:a7b:c113:: with SMTP id w19mr12670022wmi.161.1591539085345; Sun, 07 Jun 2020 07:11:25 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxEhtivajEdaPK1Pzo4yqci7IekOFKYqVhoG5Q5Z658BdHAzA73gmATehqEd3Al5/RTgQTFWg== X-Received: by 2002:a7b:c113:: with SMTP id w19mr12669994wmi.161.1591539084981; Sun, 07 Jun 2020 07:11:24 -0700 (PDT) Received: from redhat.com (bzq-82-81-31-23.red.bezeqint.net. [82.81.31.23]) by smtp.gmail.com with ESMTPSA id u9sm16315460wme.16.2020.06.07.07.11.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Jun 2020 07:11:24 -0700 (PDT) Date: Sun, 7 Jun 2020 10:11:23 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v5 01/13] vhost: option to fetch descriptors through an independent struct Message-ID: <20200607141057.704085-2-mst@redhat.com> References: <20200607141057.704085-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200607141057.704085-1-mst@redhat.com> X-Mailer: git-send-email 2.24.1.751.gd10ce2899c X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The idea is to support multiple ring formats by converting to a format-independent array of descriptors. This costs extra cycles, but we gain in ability to fetch a batch of descriptors in one go, which is good for code cache locality. When used, this causes a minor performance degradation, it's been kept as simple as possible for ease of review. A follow-up patch gets us back the performance by adding batching. To simplify benchmarking, I kept the old code around so one can switch back and forth between old and new code. This will go away in the final submission. Signed-off-by: Michael S. Tsirkin Signed-off-by: Eugenio Pérez Link: https://lore.kernel.org/r/20200401183118.8334-2-eperezma@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 302 +++++++++++++++++++++++++++++++++++++++++- drivers/vhost/vhost.h | 16 +++ 2 files changed, 317 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 172da092107e..e682ed551587 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -303,6 +303,7 @@ static void vhost_vq_reset(struct vhost_dev *dev, struct vhost_virtqueue *vq) { vq->num = 1; + vq->ndescs = 0; vq->desc = NULL; vq->avail = NULL; vq->used = NULL; @@ -373,6 +374,9 @@ static int vhost_worker(void *data) static void vhost_vq_free_iovecs(struct vhost_virtqueue *vq) { + kfree(vq->descs); + vq->descs = NULL; + vq->max_descs = 0; kfree(vq->indirect); vq->indirect = NULL; kfree(vq->log); @@ -389,6 +393,10 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; + vq->max_descs = dev->iov_limit; + vq->descs = kmalloc_array(vq->max_descs, + sizeof(*vq->descs), + GFP_KERNEL); vq->indirect = kmalloc_array(UIO_MAXIOV, sizeof(*vq->indirect), GFP_KERNEL); @@ -396,7 +404,7 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) GFP_KERNEL); vq->heads = kmalloc_array(dev->iov_limit, sizeof(*vq->heads), GFP_KERNEL); - if (!vq->indirect || !vq->log || !vq->heads) + if (!vq->indirect || !vq->log || !vq->heads || !vq->descs) goto err_nomem; } return 0; @@ -488,6 +496,8 @@ void vhost_dev_init(struct vhost_dev *dev, for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; + vq->descs = NULL; + vq->max_descs = 0; vq->log = NULL; vq->indirect = NULL; vq->heads = NULL; @@ -2315,6 +2325,296 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, } EXPORT_SYMBOL_GPL(vhost_get_vq_desc); +static struct vhost_desc *peek_split_desc(struct vhost_virtqueue *vq) +{ + BUG_ON(!vq->ndescs); + return &vq->descs[vq->ndescs - 1]; +} + +static void pop_split_desc(struct vhost_virtqueue *vq) +{ + BUG_ON(!vq->ndescs); + --vq->ndescs; +} + +#define VHOST_DESC_FLAGS (VRING_DESC_F_INDIRECT | VRING_DESC_F_WRITE | \ + VRING_DESC_F_NEXT) +static int push_split_desc(struct vhost_virtqueue *vq, struct vring_desc *desc, u16 id) +{ + struct vhost_desc *h; + + if (unlikely(vq->ndescs >= vq->max_descs)) + return -EINVAL; + h = &vq->descs[vq->ndescs++]; + h->addr = vhost64_to_cpu(vq, desc->addr); + h->len = vhost32_to_cpu(vq, desc->len); + h->flags = vhost16_to_cpu(vq, desc->flags) & VHOST_DESC_FLAGS; + h->id = id; + + return 0; +} + +static int fetch_indirect_descs(struct vhost_virtqueue *vq, + struct vhost_desc *indirect, + u16 head) +{ + struct vring_desc desc; + unsigned int i = 0, count, found = 0; + u32 len = indirect->len; + struct iov_iter from; + int ret; + + /* Sanity check */ + if (unlikely(len % sizeof desc)) { + vq_err(vq, "Invalid length in indirect descriptor: " + "len 0x%llx not multiple of 0x%zx\n", + (unsigned long long)len, + sizeof desc); + return -EINVAL; + } + + ret = translate_desc(vq, indirect->addr, len, vq->indirect, + UIO_MAXIOV, VHOST_ACCESS_RO); + if (unlikely(ret < 0)) { + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d in indirect.\n", ret); + return ret; + } + iov_iter_init(&from, READ, vq->indirect, ret, len); + + /* We will use the result as an address to read from, so most + * architectures only need a compiler barrier here. */ + read_barrier_depends(); + + count = len / sizeof desc; + /* Buffers are chained via a 16 bit next field, so + * we can have at most 2^16 of these. */ + if (unlikely(count > USHRT_MAX + 1)) { + vq_err(vq, "Indirect buffer length too big: %d\n", + indirect->len); + return -E2BIG; + } + if (unlikely(vq->ndescs + count > vq->max_descs)) { + vq_err(vq, "Too many indirect + direct descs: %d + %d\n", + vq->ndescs, indirect->len); + return -E2BIG; + } + + do { + if (unlikely(++found > count)) { + vq_err(vq, "Loop detected: last one at %u " + "indirect size %u\n", + i, count); + return -EINVAL; + } + if (unlikely(!copy_from_iter_full(&desc, sizeof(desc), &from))) { + vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n", + i, (size_t)indirect->addr + i * sizeof desc); + return -EINVAL; + } + if (unlikely(desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT))) { + vq_err(vq, "Nested indirect descriptor: idx %d, %zx\n", + i, (size_t)indirect->addr + i * sizeof desc); + return -EINVAL; + } + + /* Note: push_split_desc can't fail here: + * we never fetch unless there's space. */ + ret = push_split_desc(vq, &desc, head); + WARN_ON(ret); + } while ((i = next_desc(vq, &desc)) != -1); + return 0; +} + +static int fetch_descs(struct vhost_virtqueue *vq) +{ + unsigned int i, head, found = 0; + struct vhost_desc *last; + struct vring_desc desc; + __virtio16 avail_idx; + __virtio16 ring_head; + u16 last_avail_idx; + int ret; + + /* Check it isn't doing very strange things with descriptor numbers. */ + last_avail_idx = vq->last_avail_idx; + + if (vq->avail_idx == vq->last_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; + } + vq->avail_idx = vhost16_to_cpu(vq, avail_idx); + + if (unlikely((u16)(vq->avail_idx - last_avail_idx) > vq->num)) { + vq_err(vq, "Guest moved used index from %u to %u", + last_avail_idx, vq->avail_idx); + return -EFAULT; + } + + /* If there's nothing new since last we looked, return + * invalid. + */ + if (vq->avail_idx == last_avail_idx) + return vq->num; + + /* Only get avail ring entries after they have been + * exposed by guest. + */ + smp_rmb(); + } + + /* Grab the next descriptor number they're advertising */ + 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]); + return -EFAULT; + } + + head = vhost16_to_cpu(vq, ring_head); + + /* If their number is silly, that's an error. */ + if (unlikely(head >= vq->num)) { + vq_err(vq, "Guest says index %u > %u is available", + head, vq->num); + return -EINVAL; + } + + i = head; + do { + if (unlikely(i >= vq->num)) { + vq_err(vq, "Desc index is %u > %u, head = %u", + i, vq->num, head); + return -EINVAL; + } + if (unlikely(++found > vq->num)) { + vq_err(vq, "Loop detected: last one at %u " + "vq size %u head %u\n", + i, vq->num, head); + return -EINVAL; + } + 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); + return -EFAULT; + } + ret = push_split_desc(vq, &desc, head); + if (unlikely(ret)) { + vq_err(vq, "Failed to save descriptor: idx %d\n", i); + return -EINVAL; + } + } while ((i = next_desc(vq, &desc)) != -1); + + last = peek_split_desc(vq); + if (unlikely(last->flags & VRING_DESC_F_INDIRECT)) { + pop_split_desc(vq); + ret = fetch_indirect_descs(vq, last, head); + if (unlikely(ret < 0)) { + if (ret != -EAGAIN) + vq_err(vq, "Failure detected " + "in indirect descriptor at idx %d\n", head); + return ret; + } + } + + /* Assume notifications from guest are disabled at this point, + * if they aren't we would need to update avail_event index. */ + BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY)); + + /* On success, increment avail index. */ + vq->last_avail_idx++; + + return 0; +} + +/* This looks in the virtqueue and for the first available buffer, and converts + * it to an iovec for convenient access. Since descriptors consist of some + * number of output then some number of input descriptors, it's actually two + * iovecs, but we pack them into one and note how many of each there were. + * + * This function returns the descriptor number found, or vq->num (which is + * never a valid descriptor number) if none was found. A negative code is + * returned on error. */ +int vhost_get_vq_desc_batch(struct vhost_virtqueue *vq, + struct iovec iov[], unsigned int iov_size, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num) +{ + int ret = fetch_descs(vq); + int i; + + if (ret) + return ret; + + /* Now convert to IOV */ + /* When we start there are none of either input nor output. */ + *out_num = *in_num = 0; + if (unlikely(log)) + *log_num = 0; + + for (i = 0; i < vq->ndescs; ++i) { + unsigned iov_count = *in_num + *out_num; + struct vhost_desc *desc = &vq->descs[i]; + int access; + + if (desc->flags & ~VHOST_DESC_FLAGS) { + vq_err(vq, "Unexpected flags: 0x%x at descriptor id 0x%x\n", + desc->flags, desc->id); + ret = -EINVAL; + goto err; + } + if (desc->flags & VRING_DESC_F_WRITE) + access = VHOST_ACCESS_WO; + else + access = VHOST_ACCESS_RO; + ret = translate_desc(vq, desc->addr, + desc->len, iov + iov_count, + iov_size - iov_count, access); + if (unlikely(ret < 0)) { + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d descriptor idx %d\n", + ret, i); + goto err; + } + if (access == VHOST_ACCESS_WO) { + /* If this is an input descriptor, + * increment that count. */ + *in_num += ret; + if (unlikely(log && ret)) { + log[*log_num].addr = desc->addr; + log[*log_num].len = desc->len; + ++*log_num; + } + } else { + /* If it's an output descriptor, they're all supposed + * to come before any input descriptors. */ + if (unlikely(*in_num)) { + vq_err(vq, "Descriptor has out after in: " + "idx %d\n", i); + ret = -EINVAL; + goto err; + } + *out_num += ret; + } + + ret = desc->id; + } + + vq->ndescs = 0; + + return ret; + +err: + vhost_discard_vq_desc(vq, 1); + vq->ndescs = 0; + + return ret; +} +EXPORT_SYMBOL_GPL(vhost_get_vq_desc_batch); + /* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) { diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index c8e96a095d3b..87089d51490d 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -60,6 +60,13 @@ enum vhost_uaddr_type { VHOST_NUM_ADDRS = 3, }; +struct vhost_desc { + u64 addr; + u32 len; + u16 flags; /* VRING_DESC_F_WRITE, VRING_DESC_F_NEXT */ + u16 id; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -71,6 +78,11 @@ struct vhost_virtqueue { vring_avail_t __user *avail; vring_used_t __user *used; const struct vhost_iotlb_map *meta_iotlb[VHOST_NUM_ADDRS]; + + struct vhost_desc *descs; + int ndescs; + int max_descs; + struct file *kick; struct eventfd_ctx *call_ctx; struct eventfd_ctx *error_ctx; @@ -177,6 +189,10 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg bool vhost_vq_access_ok(struct vhost_virtqueue *vq); bool vhost_log_access_ok(struct vhost_dev *); +int vhost_get_vq_desc_batch(struct vhost_virtqueue *, + struct iovec iov[], unsigned int iov_count, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num); int vhost_get_vq_desc(struct vhost_virtqueue *, struct iovec iov[], unsigned int iov_count, unsigned int *out_num, unsigned int *in_num, From patchwork Sun Jun 7 14:11:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217960 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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 6511EC433DF for ; Sun, 7 Jun 2020 14:11:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3D3F4206A4 for ; Sun, 7 Jun 2020 14:11:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bpROrwDo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726707AbgFGOLn (ORCPT ); Sun, 7 Jun 2020 10:11:43 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:54648 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726566AbgFGOLi (ORCPT ); Sun, 7 Jun 2020 10:11:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591539097; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=JQR7Mpm9OBikwgtvyKeD/N9hz5sz6YikG7pS21JFzQo=; b=bpROrwDoGrfk/f22tIGoDnQQdwnk3dxKKY6ASNFC9bLdHKR2BIsIV9HUP8aHfl+lxSLj8p RNxpjQgPKpXmXnmplaF0TBCaL6KgC7a7hxanY8Z4wYpF2oVs30+c7d3GZGckHKsPGvSBBD ChUEd8+Sy3PtHlMiEzeVo3I6YPrUO18= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-271-kWD5AsKKN1SX5pj063FmaA-1; Sun, 07 Jun 2020 10:11:35 -0400 X-MC-Unique: kWD5AsKKN1SX5pj063FmaA-1 Received: by mail-wm1-f70.google.com with SMTP id p24so4296013wmc.1 for ; Sun, 07 Jun 2020 07:11:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=JQR7Mpm9OBikwgtvyKeD/N9hz5sz6YikG7pS21JFzQo=; b=GknpkwAatWe0aVKRuQXOeMkQWUt5BSqLClmXThDHZ5TQJ95YsSAvRcHlS62spHrDD0 WYp4bqqplrk2OPuswP1KPfUqVUHrwxI8P+o3XIsnHsw6FHh52WZ9GTie5oZx/opja6rI V4g60jh9amDXof1nzPG35boKIn8/1KrwZXchck31LOMLzie2118rXOKrjZGu8ZksMwet GKcBHY1o7ZYUCpxhMjXvU1iQ1ZNI76Qoxe0ocxw6f032MG9FqHh8ZB9ShIZsGmpweT8J oCiyaT+CK747SLP0vuDz2E7XU/P8os+9/4XZvTm+1KGQUn8en+UgqmEV8jqCDz/P+xTD 66SA== X-Gm-Message-State: AOAM530AXefBF4Bvc45mL8XjkANCThiiIPbWBt8Prk2PQqU9d3HSFVYR /63KbiSPlZNDONALtYrqNqP9kSP/uVVaUCAbZ/jbVHQOPDYs5llLpjvDhShM7HmxLOqPgH+pOtY RSReWOmhnRIbVrD24 X-Received: by 2002:adf:dc8e:: with SMTP id r14mr18094714wrj.333.1591539094201; Sun, 07 Jun 2020 07:11:34 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxqzRAoAIzc/LlIJf21AHME4RusNkUCf33IpFFYIMKnPoUw8fHgwURZWyZ6ZiKcq55sRTypMg== X-Received: by 2002:adf:dc8e:: with SMTP id r14mr18094706wrj.333.1591539094004; Sun, 07 Jun 2020 07:11:34 -0700 (PDT) Received: from redhat.com (bzq-82-81-31-23.red.bezeqint.net. [82.81.31.23]) by smtp.gmail.com with ESMTPSA id k17sm18626832wmj.15.2020.06.07.07.11.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Jun 2020 07:11:33 -0700 (PDT) Date: Sun, 7 Jun 2020 10:11:30 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v5 04/13] vhost: cleanup fetch_buf return code handling Message-ID: <20200607141057.704085-5-mst@redhat.com> References: <20200607141057.704085-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200607141057.704085-1-mst@redhat.com> X-Mailer: git-send-email 2.24.1.751.gd10ce2899c X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Return code of fetch_buf is confusing, so callers resort to tricks to get to sane values. Let's switch to something standard: 0 empty, >0 non-empty, <0 error. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 3b0609801381..5075505cfe55 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2189,6 +2189,8 @@ static int fetch_indirect_descs(struct vhost_virtqueue *vq, return 0; } +/* This function returns a value > 0 if a descriptor was found, or 0 if none were found. + * A negative code is returned on error. */ static int fetch_buf(struct vhost_virtqueue *vq) { unsigned int i, head, found = 0; @@ -2205,7 +2207,7 @@ static int fetch_buf(struct vhost_virtqueue *vq) if (unlikely(vq->avail_idx == vq->last_avail_idx)) { /* If we already have work to do, don't bother re-checking. */ if (likely(vq->ndescs)) - return vq->num; + return 0; if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) { vq_err(vq, "Failed to access avail idx at %p\n", @@ -2224,7 +2226,7 @@ static int fetch_buf(struct vhost_virtqueue *vq) * invalid. */ if (vq->avail_idx == last_avail_idx) - return vq->num; + return 0; /* Only get avail ring entries after they have been * exposed by guest. @@ -2294,12 +2296,14 @@ static int fetch_buf(struct vhost_virtqueue *vq) /* On success, increment avail index. */ vq->last_avail_idx++; - return 0; + return 1; } +/* This function returns a value > 0 if a descriptor was found, or 0 if none were found. + * A negative code is returned on error. */ static int fetch_descs(struct vhost_virtqueue *vq) { - int ret = 0; + int ret; if (unlikely(vq->first_desc >= vq->ndescs)) { vq->first_desc = 0; @@ -2309,10 +2313,14 @@ static int fetch_descs(struct vhost_virtqueue *vq) if (vq->ndescs) return 0; - while (!ret && vq->ndescs <= vhost_vq_num_batch_descs(vq)) - ret = fetch_buf(vq); + for (ret = 1; + ret > 0 && vq->ndescs <= vhost_vq_num_batch_descs(vq); + ret = fetch_buf(vq)) + ; - return vq->ndescs ? 0 : ret; + /* On success we expect some descs */ + BUG_ON(ret > 0 && !vq->ndescs); + return ret; } /* This looks in the virtqueue and for the first available buffer, and converts @@ -2331,7 +2339,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, int ret = fetch_descs(vq); int i; - if (ret) + if (ret <= 0) return ret; /* Now convert to IOV */ From patchwork Sun Jun 7 14:11:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217956 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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 9B264C433E0 for ; Sun, 7 Jun 2020 14:13:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7226B206A4 for ; Sun, 7 Jun 2020 14:13:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OlBk9YEd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727881AbgFGONB (ORCPT ); Sun, 7 Jun 2020 10:13:01 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:32061 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726741AbgFGOLs (ORCPT ); Sun, 7 Jun 2020 10:11:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591539105; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=shQxXwfF+1TlqdtG761ShfAvh9dKPfv2uFBe9eGr/Ow=; b=OlBk9YEdjG/Uj4Bav1rDbbM4korJCVsN3PiLtwesJl1Mo1x7tzv0ch5Gpn1HnKZ4geD5gw WTb4tAcygyNxTXeCgh4zTnv0FfXKBUU9Kn0CZweL+QmeHSpbL7hlVVA4HYrJR4gvjxfM5K fRKKYaLY0/v6K2W8SMGUL/5FlTJYNI0= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-328-XE30s2Z8O3uQQMknf48vCQ-1; Sun, 07 Jun 2020 10:11:41 -0400 X-MC-Unique: XE30s2Z8O3uQQMknf48vCQ-1 Received: by mail-wr1-f69.google.com with SMTP id j16so6006849wre.22 for ; Sun, 07 Jun 2020 07:11:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=shQxXwfF+1TlqdtG761ShfAvh9dKPfv2uFBe9eGr/Ow=; b=YgFdpjadHb0BzfY7Xf6tDKGLkheRClAkU0myJrx3fJWVvMZb0yi7VFmMKI5WzI3fwB YUPMuA+LSWGC3Zu/G8K9a7cjX/E/PT9RMA8ccaMAP7EpPBtQ1CRf9V+mCAnZzX4P3uu/ e6JV+jTaFVtpaNRqdZTxdVTJq21bK7FSliUkCdseQL00zYyPrZLkXl/jC0cpArRTZSPy mTChw569vsRwwBlO07W+klV7bySGjar2JI9PfmLc2T56virjrjezPNKXJEgH1hJJddAp ZuxRIh+8d5+dtaHIMQr7LI8I0IWNK0532KR/sW5kH4/lr3N+YUOc9012BcUt9RrCy7uo qgjA== X-Gm-Message-State: AOAM5317VuQOMBDxKVoppfvupR2Kj4wjm25e7eoBsh7vw3avfLXskxwY rY7skSIquxpdLGBpeijtSK/NVoiJXepWuxQZ3k/q81gxxuku2VCNHO0x+8kTGGvwbHee+1Xg0+Z muii+Ctkhz5fg8S8G X-Received: by 2002:a5d:518b:: with SMTP id k11mr20431199wrv.58.1591539100365; Sun, 07 Jun 2020 07:11:40 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxBqzko8Pims4PM36R/opFqiPZVFMZRx+PtRRKlO9uDEVtL0hbEmrdUnu0rs6gk44T0vgWJ+g== X-Received: by 2002:a5d:518b:: with SMTP id k11mr20431182wrv.58.1591539100132; Sun, 07 Jun 2020 07:11:40 -0700 (PDT) Received: from redhat.com (bzq-82-81-31-23.red.bezeqint.net. [82.81.31.23]) by smtp.gmail.com with ESMTPSA id f11sm20387998wrj.2.2020.06.07.07.11.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Jun 2020 07:11:39 -0700 (PDT) Date: Sun, 7 Jun 2020 10:11:38 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v5 07/13] vhost: format-independent API for used buffers Message-ID: <20200607141057.704085-8-mst@redhat.com> References: <20200607141057.704085-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200607141057.704085-1-mst@redhat.com> X-Mailer: git-send-email 2.24.1.751.gd10ce2899c X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add a new API that doesn't assume used ring, heads, etc. For now, we keep the old APIs around to make it easier to convert drivers. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 52 ++++++++++++++++++++++++++++++++++--------- drivers/vhost/vhost.h | 17 +++++++++++++- 2 files changed, 58 insertions(+), 11 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 3ffcba4e27e9..72ee55c810c4 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2335,13 +2335,12 @@ static int fetch_descs(struct vhost_virtqueue *vq) * number of output then some number of input descriptors, it's actually two * iovecs, but we pack them into one and note how many of each there were. * - * This function returns the descriptor number found, or vq->num (which is - * never a valid descriptor number) if none was found. A negative code is - * returned on error. */ -int vhost_get_vq_desc(struct vhost_virtqueue *vq, - struct iovec iov[], unsigned int iov_size, - unsigned int *out_num, unsigned int *in_num, - struct vhost_log *log, unsigned int *log_num) + * This function returns a value > 0 if a descriptor was found, or 0 if none were found. + * A negative code is returned on error. */ +int vhost_get_avail_buf(struct vhost_virtqueue *vq, struct vhost_buf *buf, + struct iovec iov[], unsigned int iov_size, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num) { int ret = fetch_descs(vq); int i; @@ -2354,6 +2353,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, *out_num = *in_num = 0; if (unlikely(log)) *log_num = 0; + buf->in_len = buf->out_len = 0; + buf->descs = 0; for (i = vq->first_desc; i < vq->ndescs; ++i) { unsigned iov_count = *in_num + *out_num; @@ -2383,6 +2384,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* If this is an input descriptor, * increment that count. */ *in_num += ret; + buf->in_len += desc->len; if (unlikely(log && ret)) { log[*log_num].addr = desc->addr; log[*log_num].len = desc->len; @@ -2398,9 +2400,11 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, goto err; } *out_num += ret; + buf->out_len += desc->len; } - ret = desc->id; + buf->id = desc->id; + ++buf->descs; if (!(desc->flags & VRING_DESC_F_NEXT)) break; @@ -2408,7 +2412,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, vq->first_desc = i + 1; - return ret; + return 1; err: for (i = vq->first_desc; i < vq->ndescs; ++i) @@ -2418,7 +2422,15 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, return ret; } -EXPORT_SYMBOL_GPL(vhost_get_vq_desc); +EXPORT_SYMBOL_GPL(vhost_get_avail_buf); + +/* Reverse the effect of vhost_get_avail_buf. Useful for error handling. */ +void vhost_discard_avail_bufs(struct vhost_virtqueue *vq, + struct vhost_buf *buf, unsigned count) +{ + vhost_discard_vq_desc(vq, count); +} +EXPORT_SYMBOL_GPL(vhost_discard_avail_bufs); static int __vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, @@ -2502,6 +2514,26 @@ int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) } EXPORT_SYMBOL_GPL(vhost_add_used); +int vhost_put_used_buf(struct vhost_virtqueue *vq, struct vhost_buf *buf) +{ + return vhost_add_used(vq, buf->id, buf->in_len); +} +EXPORT_SYMBOL_GPL(vhost_put_used_buf); + +int vhost_put_used_n_bufs(struct vhost_virtqueue *vq, + struct vhost_buf *bufs, unsigned count) +{ + unsigned i; + + for (i = 0; i < count; ++i) { + vq->heads[i].id = cpu_to_vhost32(vq, bufs[i].id); + vq->heads[i].len = cpu_to_vhost32(vq, bufs[i].in_len); + } + + return vhost_add_used_n(vq, vq->heads, count); +} +EXPORT_SYMBOL_GPL(vhost_put_used_n_bufs); + static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) { __u16 old, new; diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index fed36af5c444..28eea0155efb 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -67,6 +67,13 @@ struct vhost_desc { u16 id; }; +struct vhost_buf { + u32 out_len; + u32 in_len; + u16 descs; + u16 id; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -195,7 +202,12 @@ int vhost_get_vq_desc(struct vhost_virtqueue *, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num); void vhost_discard_vq_desc(struct vhost_virtqueue *, int n); - +int vhost_get_avail_buf(struct vhost_virtqueue *, struct vhost_buf *buf, + struct iovec iov[], unsigned int iov_count, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num); +void vhost_discard_avail_bufs(struct vhost_virtqueue *, + struct vhost_buf *, unsigned count); int vhost_vq_init_access(struct vhost_virtqueue *); int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len); int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads, @@ -204,6 +216,9 @@ void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *, unsigned int id, int len); void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *, struct vring_used_elem *heads, unsigned count); +int vhost_put_used_buf(struct vhost_virtqueue *, struct vhost_buf *buf); +int vhost_put_used_n_bufs(struct vhost_virtqueue *, + struct vhost_buf *bufs, unsigned count); void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *); void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *); bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *); From patchwork Sun Jun 7 14:11:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217957 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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 769EBC433E0 for ; Sun, 7 Jun 2020 14:12:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A4312067B for ; Sun, 7 Jun 2020 14:12:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="c2eQv6Hr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726788AbgFGOMo (ORCPT ); Sun, 7 Jun 2020 10:12:44 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:24837 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726791AbgFGOLu (ORCPT ); Sun, 7 Jun 2020 10:11:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591539106; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UNoiNEJvdgOZ9xjiajXEUBmq7bdVAGmYmXBWji52Kn0=; b=c2eQv6HrKqQIUFe1duT0Twel3qvtCoD7aSRRXwmYQh2q3OYMJxKypSf2EzcwIUd6Hf+u6Z t3RTlUSpVaUT4f0jlKgj2aGGrFTA4NXg4ulVKFFmHLJ5rkG3B/7AFUKfUqa1Krc5Nkh6Fy mMHblW5k3KgieIG4c7v+xcGUypkkPTU= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-382-UIR5psokN--wz4EIniA18Q-1; Sun, 07 Jun 2020 10:11:44 -0400 X-MC-Unique: UIR5psokN--wz4EIniA18Q-1 Received: by mail-wm1-f72.google.com with SMTP id b65so4289438wmb.5 for ; Sun, 07 Jun 2020 07:11:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=UNoiNEJvdgOZ9xjiajXEUBmq7bdVAGmYmXBWji52Kn0=; b=UDJON2HiINSoQLhtvTKWA25teqn65mzOtodF+BKczR2PaJFV2t4KhDv+ajv0A/PTM6 t0ERXcTOPdHSuhuaVJTatfR0ZgCbQPL18UfrCC3K9MLu5Yp0vlM1cpG6TSu7BGL2MgSD CpHnB9BdSrFU8xkaNWCEt3j0CoZqFMiUlBEWXHMoZDd0b6dZIB0wlv2PfQc8F2ANHwxm +1Gae/jVWB588j2CQDGzn9aKKFswGVMyEyhz/j5Qzb9gtelhQEzyAl0C6GP+jUZRAHSJ H0de7oLDJ9iW5qopvv+pE1t5EjO9mFWley6zs1KB5O4LprCe4pA1saKfTdzVHTMC8cwI 2PRw== X-Gm-Message-State: AOAM530kZDgAQMgh9Vne9Zvd9bC08eB5PASpilwzjSx3Tvthp6H3dF14 jUvWX3e3yWSzXYW2qWGXTuxQZKTK/pRXG0lCppRncwjQF395NJ5ZuKOzqUWQpiLDUqgQsPCufl1 O9YQxe/hyN9T4TD2N X-Received: by 2002:adf:f245:: with SMTP id b5mr18499143wrp.303.1591539102991; Sun, 07 Jun 2020 07:11:42 -0700 (PDT) X-Google-Smtp-Source: ABdhPJw8OA7pZgMkBMdE1HqvI59+uGkA/WXtF7auBUBUdg9bZYkTex0K9gv/gjYOrLDiqCrjSJQYJg== X-Received: by 2002:adf:f245:: with SMTP id b5mr18499106wrp.303.1591539102218; Sun, 07 Jun 2020 07:11:42 -0700 (PDT) Received: from redhat.com (bzq-82-81-31-23.red.bezeqint.net. [82.81.31.23]) by smtp.gmail.com with ESMTPSA id a14sm21523947wrv.20.2020.06.07.07.11.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Jun 2020 07:11:41 -0700 (PDT) Date: Sun, 7 Jun 2020 10:11:40 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v5 08/13] vhost/net: convert to new API: heads->bufs Message-ID: <20200607141057.704085-9-mst@redhat.com> References: <20200607141057.704085-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200607141057.704085-1-mst@redhat.com> X-Mailer: git-send-email 2.24.1.751.gd10ce2899c X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Convert vhost net to use the new format-agnostic API. In particular, don't poke at vq internals such as the heads array. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/net.c | 154 +++++++++++++++++++++++--------------------- 1 file changed, 82 insertions(+), 72 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index ff594eec8ae3..830fe84912a5 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -59,13 +59,13 @@ MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" * status internally; used for zerocopy tx only. */ /* Lower device DMA failed */ -#define VHOST_DMA_FAILED_LEN ((__force __virtio32)3) +#define VHOST_DMA_FAILED_LEN (3) /* Lower device DMA done */ -#define VHOST_DMA_DONE_LEN ((__force __virtio32)2) +#define VHOST_DMA_DONE_LEN (2) /* Lower device DMA in progress */ -#define VHOST_DMA_IN_PROGRESS ((__force __virtio32)1) +#define VHOST_DMA_IN_PROGRESS (1) /* Buffer unused */ -#define VHOST_DMA_CLEAR_LEN ((__force __virtio32)0) +#define VHOST_DMA_CLEAR_LEN (0) #define VHOST_DMA_IS_DONE(len) ((__force u32)(len) >= (__force u32)VHOST_DMA_DONE_LEN) @@ -112,9 +112,12 @@ struct vhost_net_virtqueue { /* last used idx for outstanding DMA zerocopy buffers */ int upend_idx; /* For TX, first used idx for DMA done zerocopy buffers - * For RX, number of batched heads + * For RX, number of batched bufs */ int done_idx; + /* Outstanding user bufs. UIO_MAXIOV in length. */ + /* TODO: we can make this smaller for sure. */ + struct vhost_buf *bufs; /* Number of XDP frames batched */ int batched_xdp; /* an array of userspace buffers info */ @@ -271,6 +274,8 @@ static void vhost_net_clear_ubuf_info(struct vhost_net *n) int i; for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { + kfree(n->vqs[i].bufs); + n->vqs[i].bufs = NULL; kfree(n->vqs[i].ubuf_info); n->vqs[i].ubuf_info = NULL; } @@ -282,6 +287,12 @@ static int vhost_net_set_ubuf_info(struct vhost_net *n) int i; for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { + n->vqs[i].bufs = kmalloc_array(UIO_MAXIOV, + sizeof(*n->vqs[i].bufs), + GFP_KERNEL); + if (!n->vqs[i].bufs) + goto err; + zcopy = vhost_net_zcopy_mask & (0x1 << i); if (!zcopy) continue; @@ -364,18 +375,18 @@ static void vhost_zerocopy_signal_used(struct vhost_net *net, int j = 0; for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) { - if (vq->heads[i].len == VHOST_DMA_FAILED_LEN) + if (nvq->bufs[i].in_len == VHOST_DMA_FAILED_LEN) vhost_net_tx_err(net); - if (VHOST_DMA_IS_DONE(vq->heads[i].len)) { - vq->heads[i].len = VHOST_DMA_CLEAR_LEN; + if (VHOST_DMA_IS_DONE(nvq->bufs[i].in_len)) { + nvq->bufs[i].in_len = VHOST_DMA_CLEAR_LEN; ++j; } else break; } while (j) { add = min(UIO_MAXIOV - nvq->done_idx, j); - vhost_add_used_and_signal_n(vq->dev, vq, - &vq->heads[nvq->done_idx], add); + vhost_put_used_n_bufs(vq, &nvq->bufs[nvq->done_idx], add); + vhost_signal(vq->dev, vq); nvq->done_idx = (nvq->done_idx + add) % UIO_MAXIOV; j -= add; } @@ -390,7 +401,7 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) rcu_read_lock_bh(); /* set len to mark this desc buffers done DMA */ - nvq->vq.heads[ubuf->desc].in_len = success ? + nvq->bufs[ubuf->desc].in_len = success ? VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN; cnt = vhost_net_ubuf_put(ubufs); @@ -452,7 +463,8 @@ static void vhost_net_signal_used(struct vhost_net_virtqueue *nvq) if (!nvq->done_idx) return; - vhost_add_used_and_signal_n(dev, vq, vq->heads, nvq->done_idx); + vhost_put_used_n_bufs(vq, nvq->bufs, nvq->done_idx); + vhost_signal(dev, vq); nvq->done_idx = 0; } @@ -558,6 +570,7 @@ static void vhost_net_busy_poll(struct vhost_net *net, static int vhost_net_tx_get_vq_desc(struct vhost_net *net, struct vhost_net_virtqueue *tnvq, + struct vhost_buf *buf, unsigned int *out_num, unsigned int *in_num, struct msghdr *msghdr, bool *busyloop_intr) { @@ -565,10 +578,10 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, struct vhost_virtqueue *rvq = &rnvq->vq; struct vhost_virtqueue *tvq = &tnvq->vq; - int r = vhost_get_vq_desc(tvq, tvq->iov, ARRAY_SIZE(tvq->iov), - out_num, in_num, NULL, NULL); + int r = vhost_get_avail_buf(tvq, buf, tvq->iov, ARRAY_SIZE(tvq->iov), + out_num, in_num, NULL, NULL); - if (r == tvq->num && tvq->busyloop_timeout) { + if (!r && tvq->busyloop_timeout) { /* Flush batched packets first */ if (!vhost_sock_zcopy(vhost_vq_get_backend(tvq))) vhost_tx_batch(net, tnvq, @@ -577,8 +590,8 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, vhost_net_busy_poll(net, rvq, tvq, busyloop_intr, false); - r = vhost_get_vq_desc(tvq, tvq->iov, ARRAY_SIZE(tvq->iov), - out_num, in_num, NULL, NULL); + r = vhost_get_avail_buf(tvq, buf, tvq->iov, ARRAY_SIZE(tvq->iov), + out_num, in_num, NULL, NULL); } return r; @@ -607,6 +620,7 @@ static size_t init_iov_iter(struct vhost_virtqueue *vq, struct iov_iter *iter, static int get_tx_bufs(struct vhost_net *net, struct vhost_net_virtqueue *nvq, + struct vhost_buf *buf, struct msghdr *msg, unsigned int *out, unsigned int *in, size_t *len, bool *busyloop_intr) @@ -614,9 +628,9 @@ static int get_tx_bufs(struct vhost_net *net, struct vhost_virtqueue *vq = &nvq->vq; int ret; - ret = vhost_net_tx_get_vq_desc(net, nvq, out, in, msg, busyloop_intr); + ret = vhost_net_tx_get_vq_desc(net, nvq, buf, out, in, msg, busyloop_intr); - if (ret < 0 || ret == vq->num) + if (ret <= 0) return ret; if (*in) { @@ -761,7 +775,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; struct vhost_virtqueue *vq = &nvq->vq; unsigned out, in; - int head; + int ret; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, @@ -773,6 +787,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) int err; int sent_pkts = 0; bool sock_can_batch = (sock->sk->sk_sndbuf == INT_MAX); + struct vhost_buf buf; do { bool busyloop_intr = false; @@ -780,13 +795,13 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) if (nvq->done_idx == VHOST_NET_BATCH) vhost_tx_batch(net, nvq, sock, &msg); - head = get_tx_bufs(net, nvq, &msg, &out, &in, &len, - &busyloop_intr); + ret = get_tx_bufs(net, nvq, &buf, &msg, &out, &in, &len, + &busyloop_intr); /* On error, stop handling until the next kick. */ - if (unlikely(head < 0)) + if (unlikely(ret < 0)) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ - if (head == vq->num) { + if (!ret) { if (unlikely(busyloop_intr)) { vhost_poll_queue(&vq->poll); } else if (unlikely(vhost_enable_notify(&net->dev, @@ -808,7 +823,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) goto done; } else if (unlikely(err != -ENOSPC)) { vhost_tx_batch(net, nvq, sock, &msg); - vhost_discard_vq_desc(vq, 1); + vhost_discard_avail_bufs(vq, &buf, 1); vhost_net_enable_vq(net, vq); break; } @@ -829,7 +844,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(sock, &msg, len); if (unlikely(err < 0)) { - vhost_discard_vq_desc(vq, 1); + vhost_discard_avail_bufs(vq, &buf, 1); vhost_net_enable_vq(net, vq); break; } @@ -837,8 +852,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) pr_debug("Truncated TX packet: len %d != %zd\n", err, len); done: - vq->heads[nvq->done_idx].id = cpu_to_vhost32(vq, head); - vq->heads[nvq->done_idx].len = 0; + nvq->bufs[nvq->done_idx] = buf; ++nvq->done_idx; } while (likely(!vhost_exceeds_weight(vq, ++sent_pkts, total_len))); @@ -850,7 +864,7 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; struct vhost_virtqueue *vq = &nvq->vq; unsigned out, in; - int head; + int ret; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, @@ -864,6 +878,7 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) struct vhost_net_ubuf_ref *uninitialized_var(ubufs); bool zcopy_used; int sent_pkts = 0; + struct vhost_buf buf; do { bool busyloop_intr; @@ -872,13 +887,13 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) vhost_zerocopy_signal_used(net, vq); busyloop_intr = false; - head = get_tx_bufs(net, nvq, &msg, &out, &in, &len, - &busyloop_intr); + ret = get_tx_bufs(net, nvq, &buf, &msg, &out, &in, &len, + &busyloop_intr); /* On error, stop handling until the next kick. */ - if (unlikely(head < 0)) + if (unlikely(ret < 0)) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ - if (head == vq->num) { + if (!ret) { if (unlikely(busyloop_intr)) { vhost_poll_queue(&vq->poll); } else if (unlikely(vhost_enable_notify(&net->dev, vq))) { @@ -897,8 +912,8 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) struct ubuf_info *ubuf; ubuf = nvq->ubuf_info + nvq->upend_idx; - vq->heads[nvq->upend_idx].id = cpu_to_vhost32(vq, head); - vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; + nvq->bufs[nvq->upend_idx] = buf; + nvq->bufs[nvq->upend_idx].in_len = VHOST_DMA_IN_PROGRESS; ubuf->callback = vhost_zerocopy_callback; ubuf->ctx = nvq->ubufs; ubuf->desc = nvq->upend_idx; @@ -930,17 +945,19 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) % UIO_MAXIOV; } - vhost_discard_vq_desc(vq, 1); + vhost_discard_avail_bufs(vq, &buf, 1); vhost_net_enable_vq(net, vq); break; } if (err != len) pr_debug("Truncated TX packet: " " len %d != %zd\n", err, len); - if (!zcopy_used) - vhost_add_used_and_signal(&net->dev, vq, head, 0); - else + if (!zcopy_used) { + vhost_put_used_buf(vq, &buf); + vhost_signal(&net->dev, vq); + } else { vhost_zerocopy_signal_used(net, vq); + } vhost_net_tx_packet(net); } while (likely(!vhost_exceeds_weight(vq, ++sent_pkts, total_len))); } @@ -1004,7 +1021,7 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk, int len = peek_head_len(rnvq, sk); if (!len && rvq->busyloop_timeout) { - /* Flush batched heads first */ + /* Flush batched bufs first */ vhost_net_signal_used(rnvq); /* Both tx vq and rx socket were polled here */ vhost_net_busy_poll(net, rvq, tvq, busyloop_intr, true); @@ -1022,11 +1039,11 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk, * @iovcount - returned count of io vectors we fill * @log - vhost log * @log_num - log offset - * @quota - headcount quota, 1 for big buffer - * returns number of buffer heads allocated, negative on error + * @quota - bufcount quota, 1 for big buffer + * returns number of buffers allocated, negative on error */ static int get_rx_bufs(struct vhost_virtqueue *vq, - struct vring_used_elem *heads, + struct vhost_buf *bufs, int datalen, unsigned *iovcount, struct vhost_log *log, @@ -1035,30 +1052,24 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, { unsigned int out, in; int seg = 0; - int headcount = 0; - unsigned d; + int bufcount = 0; int r, nlogs = 0; /* len is always initialized before use since we are always called with * datalen > 0. */ u32 uninitialized_var(len); - while (datalen > 0 && headcount < quota) { + while (datalen > 0 && bufcount < quota) { if (unlikely(seg >= UIO_MAXIOV)) { r = -ENOBUFS; goto err; } - r = vhost_get_vq_desc(vq, vq->iov + seg, - ARRAY_SIZE(vq->iov) - seg, &out, - &in, log, log_num); - if (unlikely(r < 0)) + r = vhost_get_avail_buf(vq, bufs + bufcount, vq->iov + seg, + ARRAY_SIZE(vq->iov) - seg, &out, + &in, log, log_num); + if (unlikely(r <= 0)) goto err; - d = r; - if (d == vq->num) { - r = 0; - goto err; - } if (unlikely(out || in <= 0)) { vq_err(vq, "unexpected descriptor format for RX: " "out %d, in %d\n", out, in); @@ -1069,14 +1080,12 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, nlogs += *log_num; log += *log_num; } - heads[headcount].id = cpu_to_vhost32(vq, d); len = iov_length(vq->iov + seg, in); - heads[headcount].len = cpu_to_vhost32(vq, len); datalen -= len; - ++headcount; + ++bufcount; seg += in; } - heads[headcount - 1].len = cpu_to_vhost32(vq, len + datalen); + bufs[bufcount - 1].in_len = len + datalen; *iovcount = seg; if (unlikely(log)) *log_num = nlogs; @@ -1086,9 +1095,9 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, r = UIO_MAXIOV + 1; goto err; } - return headcount; + return bufcount; err: - vhost_discard_vq_desc(vq, headcount); + vhost_discard_avail_bufs(vq, bufs, bufcount); return r; } @@ -1113,7 +1122,7 @@ static void handle_rx(struct vhost_net *net) }; size_t total_len = 0; int err, mergeable; - s16 headcount; + int bufcount; size_t vhost_hlen, sock_hlen; size_t vhost_len, sock_len; bool busyloop_intr = false; @@ -1147,14 +1156,14 @@ static void handle_rx(struct vhost_net *net) break; sock_len += sock_hlen; vhost_len = sock_len + vhost_hlen; - headcount = get_rx_bufs(vq, vq->heads + nvq->done_idx, - vhost_len, &in, vq_log, &log, - likely(mergeable) ? UIO_MAXIOV : 1); + bufcount = get_rx_bufs(vq, nvq->bufs + nvq->done_idx, + vhost_len, &in, vq_log, &log, + likely(mergeable) ? UIO_MAXIOV : 1); /* On error, stop handling until the next kick. */ - if (unlikely(headcount < 0)) + if (unlikely(bufcount < 0)) goto out; /* OK, now we need to know about added descriptors. */ - if (!headcount) { + if (!bufcount) { if (unlikely(busyloop_intr)) { vhost_poll_queue(&vq->poll); } else if (unlikely(vhost_enable_notify(&net->dev, vq))) { @@ -1171,7 +1180,7 @@ static void handle_rx(struct vhost_net *net) if (nvq->rx_ring) msg.msg_control = vhost_net_buf_consume(&nvq->rxq); /* On overrun, truncate and discard */ - if (unlikely(headcount > UIO_MAXIOV)) { + if (unlikely(bufcount > UIO_MAXIOV)) { iov_iter_init(&msg.msg_iter, READ, vq->iov, 1, 1); err = sock->ops->recvmsg(sock, &msg, 1, MSG_DONTWAIT | MSG_TRUNC); @@ -1195,7 +1204,7 @@ static void handle_rx(struct vhost_net *net) if (unlikely(err != sock_len)) { pr_debug("Discarded rx packet: " " len %d, expected %zd\n", err, sock_len); - vhost_discard_vq_desc(vq, headcount); + vhost_discard_avail_bufs(vq, nvq->bufs + nvq->done_idx, bufcount); continue; } /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ @@ -1214,15 +1223,15 @@ static void handle_rx(struct vhost_net *net) } /* TODO: Should check and handle checksum. */ - num_buffers = cpu_to_vhost16(vq, headcount); + num_buffers = cpu_to_vhost16(vq, bufcount); if (likely(mergeable) && copy_to_iter(&num_buffers, sizeof num_buffers, &fixup) != sizeof num_buffers) { vq_err(vq, "Failed num_buffers write"); - vhost_discard_vq_desc(vq, headcount); + vhost_discard_avail_bufs(vq, nvq->bufs + nvq->done_idx, bufcount); goto out; } - nvq->done_idx += headcount; + nvq->done_idx += bufcount; if (nvq->done_idx > VHOST_NET_BATCH) vhost_net_signal_used(nvq); if (unlikely(vq_log)) @@ -1314,6 +1323,7 @@ static int vhost_net_open(struct inode *inode, struct file *f) n->vqs[VHOST_NET_VQ_TX].vq.handle_kick = handle_tx_kick; n->vqs[VHOST_NET_VQ_RX].vq.handle_kick = handle_rx_kick; for (i = 0; i < VHOST_NET_VQ_MAX; i++) { + n->vqs[i].bufs = NULL; n->vqs[i].ubufs = NULL; n->vqs[i].ubuf_info = NULL; n->vqs[i].upend_idx = 0; From patchwork Sun Jun 7 14:11:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217959 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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 27BE8C433E0 for ; Sun, 7 Jun 2020 14:12:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 04DA2206A4 for ; Sun, 7 Jun 2020 14:12:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="KClBS+4S" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727019AbgFGOL5 (ORCPT ); Sun, 7 Jun 2020 10:11:57 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:54822 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726840AbgFGOLv (ORCPT ); Sun, 7 Jun 2020 10:11:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591539109; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=LkIC7lu04RjihR3CHtt6ay4K/Xfv1eAdqmqMBhW1nUc=; b=KClBS+4StlfbF/xhh1Xsa+8ZofIAwN4Csgy1OuU5MWFcVXP+KiBoc/D+7Ulm4LldWcpHyK OpAxpKZLXq1gtj/ZKUmnyAqTqllcGajFqTqwZ0GuusxWvjZM3y67PvidQnJostOo389zYR 4gjtd/sWcQSLjg3I0SS4CnixbPPLs9o= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-285-2b-qahe-NE6Bj6rgsPYz4w-1; Sun, 07 Jun 2020 10:11:48 -0400 X-MC-Unique: 2b-qahe-NE6Bj6rgsPYz4w-1 Received: by mail-wr1-f69.google.com with SMTP id o1so6011504wrm.17 for ; Sun, 07 Jun 2020 07:11:47 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=LkIC7lu04RjihR3CHtt6ay4K/Xfv1eAdqmqMBhW1nUc=; b=bSqRG5YaYfJg55XIdFdrZ8u/ovyYqZmb5BzLo/tJDwG9gknI5Uv4pY5kPXZs931mNm WHOrpnswao9DtUEz1HhhjII6fUSY0E97PukMmGp3kD3IFiA+EEjMpTtOFnjrp/s+y1ar tVnsfv8gdqtY9smydKSpCoAZW0ZMCh+Gn/hZ/CdS/u/M5YAiCv/kcJFDPC+JgBKsN6Kp Raq7C0J6cps6IXJG/qTJ9ePAArNo/yc8nf1wT8hqCHz8Fil5tVeaRS76myWo5yNkQFu/ yu0wEdScl3cMqDFwqeJFCA8vsV/iPpgNzHaYAf18diFkRqeJ+mO1c9TuIvYx69V/Q18h G9eQ== X-Gm-Message-State: AOAM530YWuNE9dA+l7mxjJ4TVOPvLxE9rqDO84aFyFo027ENthCkEkko Fw73kKQ2JYp6avOqZXDfVZws5n5+9yvuDs6EXI2cBtmeGjNmndAslFHE1D6AcLz7AOE6KJOUv3/ ZmWOJ5uL61hy9Ij7L X-Received: by 2002:a1c:7215:: with SMTP id n21mr10409314wmc.10.1591539106886; Sun, 07 Jun 2020 07:11:46 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwCfLPmb9+BZnCuC5u2jfWuqmXeqMS8Ihho5hEhJLUW08ori7QKr5nyQ1D2eMu4yFMhmwKabg== X-Received: by 2002:a1c:7215:: with SMTP id n21mr10409289wmc.10.1591539106521; Sun, 07 Jun 2020 07:11:46 -0700 (PDT) Received: from redhat.com (bzq-82-81-31-23.red.bezeqint.net. [82.81.31.23]) by smtp.gmail.com with ESMTPSA id a81sm20684853wmd.25.2020.06.07.07.11.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Jun 2020 07:11:46 -0700 (PDT) Date: Sun, 7 Jun 2020 10:11:44 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v5 10/13] vhost/test: convert to the buf API Message-ID: <20200607141057.704085-11-mst@redhat.com> References: <20200607141057.704085-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200607141057.704085-1-mst@redhat.com> X-Mailer: git-send-email 2.24.1.751.gd10ce2899c X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Signed-off-by: Michael S. Tsirkin --- drivers/vhost/test.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c index 02806d6f84ef..251fd2bf74a3 100644 --- a/drivers/vhost/test.c +++ b/drivers/vhost/test.c @@ -44,9 +44,10 @@ static void handle_vq(struct vhost_test *n) { struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ]; unsigned out, in; - int head; + int ret; size_t len, total_len = 0; void *private; + struct vhost_buf buf; mutex_lock(&vq->mutex); private = vhost_vq_get_backend(vq); @@ -58,15 +59,15 @@ static void handle_vq(struct vhost_test *n) vhost_disable_notify(&n->dev, vq); for (;;) { - head = vhost_get_vq_desc(vq, vq->iov, - ARRAY_SIZE(vq->iov), - &out, &in, - NULL, NULL); + ret = vhost_get_avail_buf(vq, vq->iov, &buf, + ARRAY_SIZE(vq->iov), + &out, &in, + NULL, NULL); /* On error, stop handling until the next kick. */ - if (unlikely(head < 0)) + if (unlikely(ret < 0)) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ - if (head == vq->num) { + if (!ret) { if (unlikely(vhost_enable_notify(&n->dev, vq))) { vhost_disable_notify(&n->dev, vq); continue; @@ -78,13 +79,14 @@ static void handle_vq(struct vhost_test *n) "out %d, int %d\n", out, in); break; } - len = iov_length(vq->iov, out); + len = buf.out_len; /* Sanity check */ if (!len) { vq_err(vq, "Unexpected 0 len for TX\n"); break; } - vhost_add_used_and_signal(&n->dev, vq, head, 0); + vhost_put_used_buf(vq, &buf); + vhost_signal(&n->dev, vq); total_len += len; if (unlikely(vhost_exceeds_weight(vq, 0, total_len))) break; From patchwork Sun Jun 7 14:11:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217958 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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,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 95BEDC433E0 for ; Sun, 7 Jun 2020 14:12:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 751742067B for ; Sun, 7 Jun 2020 14:12:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="jHBHwBpn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727844AbgFGOMT (ORCPT ); Sun, 7 Jun 2020 10:12:19 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:39225 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726993AbgFGOL6 (ORCPT ); Sun, 7 Jun 2020 10:11:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591539116; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=TEosg1cbEhe9hhKHYKqZg2N/D89Ri/A+CQJLw8Cq4Bg=; b=jHBHwBpnOsuTQP8s+dSDKTg2Pb06NACMliAd2MrMxLQVpLnE18ZdQP56oy27wjemzSU1+o Mqk/L8mhYH5BvjXHjY/jWRonomQSCgTvhF/rj33++IHtfzdv1eZjWB9x/mGzx8Efro3j/t 4Ymt6yFd9c11ZmG4Zx6FS30Zm5h1vYk= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-6-vUNPCLWrOpqJis4_HVZTYQ-1; Sun, 07 Jun 2020 10:11:52 -0400 X-MC-Unique: vUNPCLWrOpqJis4_HVZTYQ-1 Received: by mail-wr1-f69.google.com with SMTP id t5so6032528wro.20 for ; Sun, 07 Jun 2020 07:11:52 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=TEosg1cbEhe9hhKHYKqZg2N/D89Ri/A+CQJLw8Cq4Bg=; b=JLTsjcEuuFBgcVARsdLwCTSFw9DTxr/OMtLerAFZzDyBovQkg84p4ctIGpLjmfDxm7 hb95bnLUGDDGcKoS7HhAtJNUKfFNgo7n/5G51Yd6o5HwMA6xCJrBmvJsywU7tbXBi9eV k3v4QtAXpfPyndHJHskddB1q/EINx28mUukFsgPsx5IIEbpRsMNd4XcYV+FGgneVb7+Q FHoVnGibuP2WorM9WsHlT38K9jaRhSqSKxsJsyekMDtCH3YQbVyqhbgAxIg+xWKNdCu2 QJpk1mvDEZYcOjkfz3HvQEV70zpNak2qwLF90Jt1rAP8z9SLmALKvYY2tIZzPDs6YOVU WrHg== X-Gm-Message-State: AOAM530/6JTeUkGD7SNvVt8q3W5H+xPuG3WNYIJ/3h0HR4MuOAe1PWeD Q6Culrk8c83KfjEjhmDj0ItCANy0oJyZCRJ5KSnjBgpcdOMtdg+5RCkq+1nlH5qRNmBXEOJebc1 hH9Aoqmj0Pv1cjBan X-Received: by 2002:a5d:500c:: with SMTP id e12mr19107224wrt.359.1591539111401; Sun, 07 Jun 2020 07:11:51 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyWm7fzH3GrdTvffSzx7586DHu5PzZq1QUCLkQIW8gnb+63gz4UqKFoDHZvxyrR4qeM53Cywg== X-Received: by 2002:a5d:500c:: with SMTP id e12mr19107213wrt.359.1591539111193; Sun, 07 Jun 2020 07:11:51 -0700 (PDT) Received: from redhat.com (bzq-82-81-31-23.red.bezeqint.net. [82.81.31.23]) by smtp.gmail.com with ESMTPSA id i10sm19790175wrw.51.2020.06.07.07.11.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Jun 2020 07:11:50 -0700 (PDT) Date: Sun, 7 Jun 2020 10:11:49 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com, Stefan Hajnoczi , Stefano Garzarella Subject: [PATCH RFC v5 12/13] vhost/vsock: switch to the buf API Message-ID: <20200607141057.704085-13-mst@redhat.com> References: <20200607141057.704085-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200607141057.704085-1-mst@redhat.com> X-Mailer: git-send-email 2.24.1.751.gd10ce2899c X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org A straight-forward conversion. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vsock.c | 30 ++++++++++++++++++------------ 1 file changed, 18 insertions(+), 12 deletions(-) diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index a483cec31d5c..61c6d3dd2ae3 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -103,7 +103,8 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, unsigned out, in; size_t nbytes; size_t iov_len, payload_len; - int head; + struct vhost_buf buf; + int ret; spin_lock_bh(&vsock->send_pkt_list_lock); if (list_empty(&vsock->send_pkt_list)) { @@ -117,16 +118,17 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, list_del_init(&pkt->list); spin_unlock_bh(&vsock->send_pkt_list_lock); - head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), - &out, &in, NULL, NULL); - if (head < 0) { + ret = vhost_get_avail_buf(vq, &buf, + vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + if (ret < 0) { spin_lock_bh(&vsock->send_pkt_list_lock); list_add(&pkt->list, &vsock->send_pkt_list); spin_unlock_bh(&vsock->send_pkt_list_lock); break; } - if (head == vq->num) { + if (!ret) { spin_lock_bh(&vsock->send_pkt_list_lock); list_add(&pkt->list, &vsock->send_pkt_list); spin_unlock_bh(&vsock->send_pkt_list_lock); @@ -186,7 +188,8 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, */ virtio_transport_deliver_tap_pkt(pkt); - vhost_add_used(vq, head, sizeof(pkt->hdr) + payload_len); + buf.in_len = sizeof(pkt->hdr) + payload_len; + vhost_put_used_buf(vq, &buf); added = true; pkt->off += payload_len; @@ -440,7 +443,8 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work) struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, dev); struct virtio_vsock_pkt *pkt; - int head, pkts = 0, total_len = 0; + int ret, pkts = 0, total_len = 0; + struct vhost_buf buf; unsigned int out, in; bool added = false; @@ -461,12 +465,13 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work) goto no_more_replies; } - head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), - &out, &in, NULL, NULL); - if (head < 0) + ret = vhost_get_avail_buf(vq, &buf, + vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + if (ret < 0) break; - if (head == vq->num) { + if (!ret) { if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { vhost_disable_notify(&vsock->dev, vq); continue; @@ -494,7 +499,8 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work) virtio_transport_free_pkt(pkt); len += sizeof(pkt->hdr); - vhost_add_used(vq, head, len); + buf.in_len = len; + vhost_put_used_buf(vq, &buf); total_len += len; added = true; } while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));