From patchwork Mon Aug 30 16:32:24 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 63103 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 9145AB70F9 for ; Tue, 31 Aug 2010 03:26:41 +1000 (EST) Received: from localhost ([127.0.0.1]:47457 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Oq87y-00014i-Pc for incoming@patchwork.ozlabs.org; Mon, 30 Aug 2010 13:26:38 -0400 Received: from [140.186.70.92] (port=42444 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Oq7Ja-0001zi-QS for qemu-devel@nongnu.org; Mon, 30 Aug 2010 12:34:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1Oq7HU-00051w-U0 for qemu-devel@nongnu.org; Mon, 30 Aug 2010 12:32:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34179) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1Oq7HU-00051l-LU for qemu-devel@nongnu.org; Mon, 30 Aug 2010 12:32:24 -0400 Received: from int-mx08.intmail.prod.int.phx2.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o7UGWM1b006618 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 30 Aug 2010 12:32:23 -0400 Received: from dhcp-5-188.str.redhat.com (dhcp-5-175.str.redhat.com [10.32.5.175]) by int-mx08.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o7UGWKtb029322; Mon, 30 Aug 2010 12:32:21 -0400 From: Kevin Wolf To: anthony@codemonkey.ws Date: Mon, 30 Aug 2010 18:32:24 +0200 Message-Id: <1283185953-30639-2-git-send-email-kwolf@redhat.com> In-Reply-To: <1283185953-30639-1-git-send-email-kwolf@redhat.com> References: <1283185953-30639-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.21 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH 01/10] virtio: Factor virtqueue_map_sg out X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Separate the mapping of requests to host memory from the descriptor iteration. The next patch will make use of it in a different context. Signed-off-by: Kevin Wolf --- hw/virtio.c | 38 ++++++++++++++++++++++++-------------- hw/virtio.h | 3 +++ 2 files changed, 27 insertions(+), 14 deletions(-) diff --git a/hw/virtio.c b/hw/virtio.c index 4475bb3..85312b3 100644 --- a/hw/virtio.c +++ b/hw/virtio.c @@ -360,11 +360,26 @@ int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes) return 0; } +void virtqueue_map_sg(struct iovec *sg, target_phys_addr_t *addr, + size_t num_sg, int is_write) +{ + unsigned int i; + target_phys_addr_t len; + + for (i = 0; i < num_sg; i++) { + len = sg[i].iov_len; + sg[i].iov_base = cpu_physical_memory_map(addr[i], &len, is_write); + if (sg[i].iov_base == NULL || len != sg[i].iov_len) { + fprintf(stderr, "virtio: trying to map MMIO memory\n"); + exit(1); + } + } +} + int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem) { unsigned int i, head, max; target_phys_addr_t desc_pa = vq->vring.desc; - target_phys_addr_t len; if (!virtqueue_num_heads(vq, vq->last_avail_idx)) return 0; @@ -388,28 +403,19 @@ int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem) i = 0; } + /* Collect all the descriptors */ do { struct iovec *sg; - int is_write = 0; if (vring_desc_flags(desc_pa, i) & VRING_DESC_F_WRITE) { elem->in_addr[elem->in_num] = vring_desc_addr(desc_pa, i); sg = &elem->in_sg[elem->in_num++]; - is_write = 1; - } else + } else { + elem->out_addr[elem->out_num] = vring_desc_addr(desc_pa, i); sg = &elem->out_sg[elem->out_num++]; + } - /* Grab the first descriptor, and check it's OK. */ sg->iov_len = vring_desc_len(desc_pa, i); - len = sg->iov_len; - - sg->iov_base = cpu_physical_memory_map(vring_desc_addr(desc_pa, i), - &len, is_write); - - if (sg->iov_base == NULL || len != sg->iov_len) { - fprintf(stderr, "virtio: trying to map MMIO memory\n"); - exit(1); - } /* If we've got too many, that implies a descriptor loop. */ if ((elem->in_num + elem->out_num) > max) { @@ -418,6 +424,10 @@ int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem) } } while ((i = virtqueue_next_desc(desc_pa, i, max)) != max); + /* Now map what we have collected */ + virtqueue_map_sg(elem->in_sg, elem->in_addr, elem->in_num, 1); + virtqueue_map_sg(elem->out_sg, elem->out_addr, elem->out_num, 0); + elem->index = head; vq->inuse++; diff --git a/hw/virtio.h b/hw/virtio.h index 5836ab6..1deeb2c 100644 --- a/hw/virtio.h +++ b/hw/virtio.h @@ -81,6 +81,7 @@ typedef struct VirtQueueElement unsigned int out_num; unsigned int in_num; target_phys_addr_t in_addr[VIRTQUEUE_MAX_SIZE]; + target_phys_addr_t out_addr[VIRTQUEUE_MAX_SIZE]; struct iovec in_sg[VIRTQUEUE_MAX_SIZE]; struct iovec out_sg[VIRTQUEUE_MAX_SIZE]; } VirtQueueElement; @@ -142,6 +143,8 @@ void virtqueue_flush(VirtQueue *vq, unsigned int count); void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len, unsigned int idx); +void virtqueue_map_sg(struct iovec *sg, target_phys_addr_t *addr, + size_t num_sg, int is_write); int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem); int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes);