From patchwork Tue Sep 24 01:31:53 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 13810024 X-Patchwork-Delegate: kuba@kernel.org Received: from out30-101.freemail.mail.aliyun.com (out30-101.freemail.mail.aliyun.com [115.124.30.101]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 468BB18D; Tue, 24 Sep 2024 01:32:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.101 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727141537; cv=none; b=Gws9kgLl8UEkhTfd6l6E4hAQAXfKcEGwf0zgIZnMqv/4CoF9jyZYttM9/k1FpBRgMQmKm8swermRIls7niOKz9jS5bRSEFQeNT9qurBWPYcPv968KVPS7fVvKLKoNxB8utXKFM5EBIiq5Gfoav/RMBD7ATFB+lL3BjM5kcb6jEw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727141537; c=relaxed/simple; bh=DAON7CC1MrBTUr4PRaED8Jr0oZmqEyEBX53lraJJzkc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=a+dtST0W7DVLJ8dBSfP7Y8SfC5Bwlpm4y9jA8lciWTSZzuVr7VyoKVBdnCW8W/YNLSjL8oQRlivrU9wCAYRXQ3lOGxhDg95JIsLDliZX1DKbaz8lK3yk2O2ZOJT1UJCvtp4rVnCv3Dl+nP4CwvyLRd1ZL1M9SOAOOEs+nksEJLU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=P1s/GhIF; arc=none smtp.client-ip=115.124.30.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="P1s/GhIF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1727141526; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=BFKxNeN7wLQvASqqybYxd1jhmqhgoO6ptEV25pUf63M=; b=P1s/GhIFW4igZFrQBtyqBiOwai+BB1SHIRTH3aZMfxAEMTAXrCylGKzB0bLVGNmYmdy5KJpR4lvXB7eIFrWgc9VbSCw8gMG/89QxGDEar2TpNbYPaBZQcqxm88E3w/xl2ppSX/hyevmrkX8hs5+u37Pkaakc5V/zJ9Q/x9KF/JU= Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0WFdu-R5_1727141525) by smtp.aliyun-inc.com; Tue, 24 Sep 2024 09:32:06 +0800 From: Xuan Zhuo To: netdev@vger.kernel.org Cc: "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , =?utf-8?q?Eugenio_P=C3=A9rez?= , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , virtualization@lists.linux.dev, bpf@vger.kernel.org Subject: [RFC net-next v1 01/12] virtio_ring: introduce vring_need_unmap_buffer Date: Tue, 24 Sep 2024 09:31:53 +0800 Message-Id: <20240924013204.13763-2-xuanzhuo@linux.alibaba.com> X-Mailer: git-send-email 2.32.0.3.g01195cf9f In-Reply-To: <20240924013204.13763-1-xuanzhuo@linux.alibaba.com> References: <20240924013204.13763-1-xuanzhuo@linux.alibaba.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Git-Hash: 83bb687d4b73 X-Patchwork-Delegate: kuba@kernel.org X-Patchwork-State: RFC To make the code readable, introduce vring_need_unmap_buffer() to replace do_unmap. use_dma_api premapped -> vring_need_unmap_buffer() 1. false false false 2. true false true 3. true true false Signed-off-by: Xuan Zhuo Acked-by: Jason Wang --- drivers/virtio/virtio_ring.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index be7309b1e860..228e9fbcba3f 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -175,11 +175,6 @@ struct vring_virtqueue { /* Do DMA mapping by driver */ bool premapped; - /* Do unmap or not for desc. Just when premapped is False and - * use_dma_api is true, this is true. - */ - bool do_unmap; - /* Head of free buffer list. */ unsigned int free_head; /* Number we've added since last sync. */ @@ -297,6 +292,11 @@ static bool vring_use_dma_api(const struct virtio_device *vdev) return false; } +static bool vring_need_unmap_buffer(const struct vring_virtqueue *vring) +{ + return vring->use_dma_api && !vring->premapped; +} + size_t virtio_max_dma_size(const struct virtio_device *vdev) { size_t max_segment_size = SIZE_MAX; @@ -445,7 +445,7 @@ static void vring_unmap_one_split_indirect(const struct vring_virtqueue *vq, { u16 flags; - if (!vq->do_unmap) + if (!vring_need_unmap_buffer(vq)) return; flags = virtio16_to_cpu(vq->vq.vdev, desc->flags); @@ -475,7 +475,7 @@ static unsigned int vring_unmap_one_split(const struct vring_virtqueue *vq, (flags & VRING_DESC_F_WRITE) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); } else { - if (!vq->do_unmap) + if (!vring_need_unmap_buffer(vq)) goto out; dma_unmap_page(vring_dma_dev(vq), @@ -643,7 +643,7 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, } /* Last one doesn't continue. */ desc[prev].flags &= cpu_to_virtio16(_vq->vdev, ~VRING_DESC_F_NEXT); - if (!indirect && vq->do_unmap) + if (!indirect && vring_need_unmap_buffer(vq)) vq->split.desc_extra[prev & (vq->split.vring.num - 1)].flags &= ~VRING_DESC_F_NEXT; @@ -802,7 +802,7 @@ static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head, VRING_DESC_F_INDIRECT)); BUG_ON(len == 0 || len % sizeof(struct vring_desc)); - if (vq->do_unmap) { + if (vring_need_unmap_buffer(vq)) { for (j = 0; j < len / sizeof(struct vring_desc); j++) vring_unmap_one_split_indirect(vq, &indir_desc[j]); } @@ -1236,7 +1236,7 @@ static void vring_unmap_extra_packed(const struct vring_virtqueue *vq, (flags & VRING_DESC_F_WRITE) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); } else { - if (!vq->do_unmap) + if (!vring_need_unmap_buffer(vq)) return; dma_unmap_page(vring_dma_dev(vq), @@ -1251,7 +1251,7 @@ static void vring_unmap_desc_packed(const struct vring_virtqueue *vq, { u16 flags; - if (!vq->do_unmap) + if (!vring_need_unmap_buffer(vq)) return; flags = le16_to_cpu(desc->flags); @@ -1632,7 +1632,7 @@ static void detach_buf_packed(struct vring_virtqueue *vq, if (!desc) return; - if (vq->do_unmap) { + if (vring_need_unmap_buffer(vq)) { len = vq->packed.desc_extra[id].len; for (i = 0; i < len / sizeof(struct vring_packed_desc); i++) @@ -2091,7 +2091,6 @@ static struct virtqueue *vring_create_virtqueue_packed( vq->dma_dev = dma_dev; vq->use_dma_api = vring_use_dma_api(vdev); vq->premapped = false; - vq->do_unmap = vq->use_dma_api; vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && !context; @@ -2636,7 +2635,6 @@ static struct virtqueue *__vring_new_virtqueue(unsigned int index, vq->dma_dev = dma_dev; vq->use_dma_api = vring_use_dma_api(vdev); vq->premapped = false; - vq->do_unmap = vq->use_dma_api; vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && !context; @@ -2799,7 +2797,6 @@ int virtqueue_set_dma_premapped(struct virtqueue *_vq) } vq->premapped = true; - vq->do_unmap = false; END_USE(vq);