From patchwork Wed Sep 29 15:11:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincent Whitchurch X-Patchwork-Id: 12525767 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9656CC4321E for ; Wed, 29 Sep 2021 15:11:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6430361503 for ; Wed, 29 Sep 2021 15:11:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345181AbhI2PNN (ORCPT ); Wed, 29 Sep 2021 11:13:13 -0400 Received: from smtp2.axis.com ([195.60.68.18]:4224 "EHLO smtp2.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345075AbhI2PNF (ORCPT ); Wed, 29 Sep 2021 11:13:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; q=dns/txt; s=axis-central1; t=1632928284; x=1664464284; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=rFsuG5yulChU1RiHnkTswRVXWfw8Xi3XkNlyr5Zr+o0=; b=Sd8rxFQrnjJwSZE60Wd1AfRUEX3mF0XIdi4ONNwFGW2GNdgreiOj4ACL 5lGFBmuNOrJbyZrnU+ro2usXimiv+tcN+iMioIOiF3ERLuS3bvpEMFchI w5UXzhAq5b/LqAAAnDmGwQULcLtNxwuGvZSi9cYTIAQf7kRXQ7uNHWSkF a64+6L9ECKk1wtVBXEi8TZ9T+XO3ix5dNm8sTKJ1j2XvUNARcAcfzsN9Z T+ygVmKcJIymM/i8qV4eaLl8ohMuyaJ1obt6YlROyc81NeGvgz+hzKUEM ivTQAhhVgoqWMdxFFXhtqRz3biP8p8Y/LwD0ugYlAHlncxuGtjN62+p6g g==; From: Vincent Whitchurch To: , CC: , , , , , , , , Vincent Whitchurch Subject: [RFC PATCH 03/10] vhost: add iov wrapper Date: Wed, 29 Sep 2021 17:11:12 +0200 Message-ID: <20210929151119.14778-4-vincent.whitchurch@axis.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20210929151119.14778-1-vincent.whitchurch@axis.com> References: <20210929151119.14778-1-vincent.whitchurch@axis.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-State: RFC In order to prepare for supporting buffers in kernel space, add a vhost_iov struct to wrap the userspace iovec, add helper functions for accessing this struct, and use these helpers from all vhost drivers. Signed-off-by: Vincent Whitchurch --- drivers/vhost/net.c | 13 ++++++------ drivers/vhost/scsi.c | 30 +++++++++++++-------------- drivers/vhost/test.c | 2 +- drivers/vhost/vhost.c | 25 +++++++++++----------- drivers/vhost/vhost.h | 48 +++++++++++++++++++++++++++++++++++++------ drivers/vhost/vsock.c | 8 ++++---- 6 files changed, 81 insertions(+), 45 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 28ef323882fb..8f82b646d4af 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -607,9 +607,9 @@ static size_t init_iov_iter(struct vhost_virtqueue *vq, struct iov_iter *iter, size_t hdr_size, int out) { /* Skip header. TODO: support TSO. */ - size_t len = iov_length(vq->iov, out); + size_t len = vhost_iov_length(vq, vq->iov, out); - iov_iter_init(iter, WRITE, vq->iov, out, len); + vhost_iov_iter_init(vq, iter, WRITE, vq->iov, out, len); iov_iter_advance(iter, hdr_size); return iov_iter_count(iter); @@ -1080,7 +1080,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, log += *log_num; } heads[headcount].id = cpu_to_vhost32(vq, d); - len = iov_length(vq->iov + seg, in); + len = vhost_iov_length(vq, vq->iov + seg, in); heads[headcount].len = cpu_to_vhost32(vq, len); datalen -= len; ++headcount; @@ -1182,14 +1182,14 @@ static void handle_rx(struct vhost_net *net) msg.msg_control = vhost_net_buf_consume(&nvq->rxq); /* On overrun, truncate and discard */ if (unlikely(headcount > UIO_MAXIOV)) { - iov_iter_init(&msg.msg_iter, READ, vq->iov, 1, 1); + vhost_iov_iter_init(vq, &msg.msg_iter, READ, vq->iov, 1, 1); err = sock->ops->recvmsg(sock, &msg, 1, MSG_DONTWAIT | MSG_TRUNC); pr_debug("Discarded rx packet: len %zd\n", sock_len); continue; } /* We don't need to be notified again. */ - iov_iter_init(&msg.msg_iter, READ, vq->iov, in, vhost_len); + vhost_iov_iter_init(vq, &msg.msg_iter, READ, vq->iov, in, vhost_len); fixup = msg.msg_iter; if (unlikely((vhost_hlen))) { /* We will supply the header ourselves @@ -1212,8 +1212,7 @@ static void handle_rx(struct vhost_net *net) if (unlikely(vhost_hlen)) { if (copy_to_iter(&hdr, sizeof(hdr), &fixup) != sizeof(hdr)) { - vq_err(vq, "Unable to write vnet_hdr " - "at addr %p\n", vq->iov->iov_base); + vq_err(vq, "Unable to write vnet_hdr"); goto out; } } else { diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index bcf53685439d..22a372b52165 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -80,7 +80,7 @@ struct vhost_scsi_cmd { struct scatterlist *tvc_prot_sgl; struct page **tvc_upages; /* Pointer to response header iovec */ - struct iovec tvc_resp_iov; + struct vhost_iov tvc_resp_iov; /* Pointer to vhost_scsi for our device */ struct vhost_scsi *tvc_vhost; /* Pointer to vhost_virtqueue for the cmd */ @@ -208,7 +208,7 @@ struct vhost_scsi_tmf { struct se_cmd se_cmd; u8 scsi_resp; struct vhost_scsi_inflight *inflight; - struct iovec resp_iov; + struct vhost_iov resp_iov; int in_iovs; int vq_desc; }; @@ -487,9 +487,9 @@ vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt) return; } - if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) { + if (vhost_iov_len(vq, &vq->iov[out]) != sizeof(struct virtio_scsi_event)) { vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n", - vq->iov[out].iov_len); + vhost_iov_len(vq, &vq->iov[out])); vs->vs_events_missed = true; return; } @@ -499,7 +499,7 @@ vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt) vs->vs_events_missed = false; } - iov_iter_init(&iov_iter, READ, &vq->iov[out], in, sizeof(*event)); + vhost_iov_iter_init(vq, &iov_iter, READ, &vq->iov[out], in, sizeof(*event)); ret = copy_to_iter(event, sizeof(*event), &iov_iter); if (ret == sizeof(*event)) @@ -559,8 +559,8 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work) memcpy(v_rsp.sense, cmd->tvc_sense_buf, se_cmd->scsi_sense_length); - iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov, - cmd->tvc_in_iovs, sizeof(v_rsp)); + vhost_iov_iter_init(&vs->vqs[0].vq, &iov_iter, READ, &cmd->tvc_resp_iov, + cmd->tvc_in_iovs, sizeof(v_rsp)); ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter); if (likely(ret == sizeof(v_rsp))) { struct vhost_scsi_virtqueue *q; @@ -809,7 +809,7 @@ vhost_scsi_send_bad_target(struct vhost_scsi *vs, struct iov_iter iov_iter; int ret; - iov_iter_init(&iov_iter, READ, &vq->iov[out], in, sizeof(rsp)); + vhost_iov_iter_init(vq, &iov_iter, READ, &vq->iov[out], in, sizeof(rsp)); memset(&rsp, 0, sizeof(rsp)); rsp.response = VIRTIO_SCSI_S_BAD_TARGET; @@ -850,8 +850,8 @@ vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq, * Get the size of request and response buffers. * FIXME: Not correct for BIDI operation */ - vc->out_size = iov_length(vq->iov, vc->out); - vc->in_size = iov_length(&vq->iov[vc->out], vc->in); + vc->out_size = vhost_iov_length(vq, vq->iov, vc->out); + vc->in_size = vhost_iov_length(vq, &vq->iov[vc->out], vc->in); /* * Copy over the virtio-scsi request header, which for a @@ -863,7 +863,7 @@ vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq, * point at the start of the outgoing WRITE payload, if * DMA_TO_DEVICE is set. */ - iov_iter_init(&vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size); + vhost_iov_iter_init(vq, &vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size); ret = 0; done: @@ -1015,7 +1015,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) data_direction = DMA_FROM_DEVICE; exp_data_len = vc.in_size - vc.rsp_size; - iov_iter_init(&in_iter, READ, &vq->iov[vc.out], vc.in, + vhost_iov_iter_init(vq, &in_iter, READ, &vq->iov[vc.out], vc.in, vc.rsp_size + exp_data_len); iov_iter_advance(&in_iter, vc.rsp_size); data_iter = in_iter; @@ -1134,7 +1134,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) static void vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq, - int in_iovs, int vq_desc, struct iovec *resp_iov, + int in_iovs, int vq_desc, struct vhost_iov *resp_iov, int tmf_resp_code) { struct virtio_scsi_ctrl_tmf_resp rsp; @@ -1145,7 +1145,7 @@ vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq, memset(&rsp, 0, sizeof(rsp)); rsp.response = tmf_resp_code; - iov_iter_init(&iov_iter, READ, resp_iov, in_iovs, sizeof(rsp)); + vhost_iov_iter_init(vq, &iov_iter, READ, resp_iov, in_iovs, sizeof(rsp)); ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter); if (likely(ret == sizeof(rsp))) @@ -1237,7 +1237,7 @@ vhost_scsi_send_an_resp(struct vhost_scsi *vs, memset(&rsp, 0, sizeof(rsp)); /* event_actual = 0 */ rsp.response = VIRTIO_SCSI_S_OK; - iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp)); + vhost_iov_iter_init(vq, &iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp)); ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter); if (likely(ret == sizeof(rsp))) diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c index a09dedc79f68..95794b0ea4ad 100644 --- a/drivers/vhost/test.c +++ b/drivers/vhost/test.c @@ -78,7 +78,7 @@ static void handle_vq(struct vhost_test *n) "out %d, int %d\n", out, in); break; } - len = iov_length(vq->iov, out); + len = vhost_iov_length(vq, vq->iov, out); /* Sanity check */ if (!len) { vq_err(vq, "Unexpected 0 len for TX\n"); diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 108994f386f7..ce81eee2a3fa 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -812,7 +812,7 @@ static bool memory_access_ok(struct vhost_dev *d, struct vhost_iotlb *umem, } static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, - struct iovec iov[], int iov_size, int access); + struct vhost_iov iov[], int iov_size, int access); static int vhost_copy_to_user(struct vhost_virtqueue *vq, void __user *to, const void *from, unsigned size) @@ -840,7 +840,7 @@ static int vhost_copy_to_user(struct vhost_virtqueue *vq, void __user *to, VHOST_ACCESS_WO); if (ret < 0) goto out; - iov_iter_init(&t, WRITE, vq->iotlb_iov, ret, size); + iov_iter_init(&t, WRITE, &vq->iotlb_iov->iovec, ret, size); ret = copy_to_iter(from, size, &t); if (ret == size) ret = 0; @@ -879,7 +879,7 @@ static int vhost_copy_from_user(struct vhost_virtqueue *vq, void *to, (unsigned long long) size); goto out; } - iov_iter_init(&f, READ, vq->iotlb_iov, ret, size); + iov_iter_init(&f, READ, &vq->iotlb_iov->iovec, ret, size); ret = copy_from_iter(to, size, &f); if (ret == size) ret = 0; @@ -905,14 +905,14 @@ static void __user *__vhost_get_user_slow(struct vhost_virtqueue *vq, return NULL; } - if (ret != 1 || vq->iotlb_iov[0].iov_len != size) { + if (ret != 1 || vq->iotlb_iov->iovec.iov_len != size) { vq_err(vq, "Non atomic userspace memory access: uaddr " "%p size 0x%llx\n", addr, (unsigned long long) size); return NULL; } - return vq->iotlb_iov[0].iov_base; + return vq->iotlb_iov->iovec.iov_base; } /* This function should be called after iotlb @@ -1906,7 +1906,7 @@ static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len) static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len) { - struct iovec *iov = vq->log_iov; + struct iovec *iov = &vq->log_iov->iovec; int i, ret; if (!vq->iotlb) @@ -1928,8 +1928,9 @@ static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len) } int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, - unsigned int log_num, u64 len, struct iovec *iov, int count) + unsigned int log_num, u64 len, struct vhost_iov *viov, int count) { + struct iovec *iov = &viov->iovec; int i, r; /* Make sure data written is seen before log. */ @@ -2035,7 +2036,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq) EXPORT_SYMBOL_GPL(vhost_vq_init_access); static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, - struct iovec iov[], int iov_size, int access) + struct vhost_iov iov[], int iov_size, int access) { const struct vhost_iotlb_map *map; struct vhost_dev *dev = vq->dev; @@ -2064,7 +2065,7 @@ static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, break; } - _iov = iov + ret; + _iov = &iov->iovec + ret; size = map->size - addr + map->start; _iov->iov_len = min((u64)len - s, size); _iov->iov_base = (void __user *)(unsigned long) @@ -2096,7 +2097,7 @@ static unsigned next_desc(struct vhost_virtqueue *vq, struct vring_desc *desc) } static int get_indirect(struct vhost_virtqueue *vq, - struct iovec iov[], unsigned int iov_size, + struct vhost_iov iov[], unsigned int iov_size, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num, struct vring_desc *indirect) @@ -2123,7 +2124,7 @@ static int get_indirect(struct vhost_virtqueue *vq, vq_err(vq, "Translation failure %d in indirect.\n", ret); return ret; } - iov_iter_init(&from, READ, vq->indirect, ret, len); + vhost_iov_iter_init(vq, &from, READ, vq->indirect, ret, len); count = len / sizeof desc; /* Buffers are chained via a 16 bit next field, so * we can have at most 2^16 of these. */ @@ -2197,7 +2198,7 @@ static int get_indirect(struct vhost_virtqueue *vq, * 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, + struct vhost_iov iov[], unsigned int iov_size, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num) { diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index b1db4ffe75f0..69aec724ef7f 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -65,6 +65,12 @@ struct vhost_vring_call { struct irq_bypass_producer producer; }; +struct vhost_iov { + union { + struct iovec iovec; + }; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -110,9 +116,9 @@ struct vhost_virtqueue { bool log_used; u64 log_addr; - struct iovec iov[UIO_MAXIOV]; - struct iovec iotlb_iov[64]; - struct iovec *indirect; + struct vhost_iov iov[UIO_MAXIOV]; + struct vhost_iov iotlb_iov[64]; + struct vhost_iov *indirect; struct vring_used_elem *heads; /* Protected by virtqueue mutex. */ struct vhost_iotlb *umem; @@ -123,7 +129,7 @@ struct vhost_virtqueue { /* Log write descriptors */ void __user *log_base; struct vhost_log *log; - struct iovec log_iov[64]; + struct vhost_iov log_iov[64]; /* Ring endianness. Defaults to legacy native endianness. * Set to true when starting a modern virtio device. */ @@ -167,6 +173,26 @@ struct vhost_dev { struct vhost_iotlb_msg *msg); }; +static inline size_t vhost_iov_length(const struct vhost_virtqueue *vq, struct vhost_iov *iov, + unsigned long nr_segs) +{ + return iov_length(&iov->iovec, nr_segs); +} + +static inline size_t vhost_iov_len(const struct vhost_virtqueue *vq, struct vhost_iov *iov) +{ + return iov->iovec.iov_len; +} + +static inline void vhost_iov_iter_init(const struct vhost_virtqueue *vq, + struct iov_iter *i, unsigned int direction, + struct vhost_iov *iov, + unsigned long nr_segs, + size_t count) +{ + iov_iter_init(i, direction, &iov->iovec, nr_segs, count); +} + bool vhost_exceeds_weight(struct vhost_virtqueue *vq, int pkts, int total_len); void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs, int iov_limit, int weight, int byte_weight, @@ -186,9 +212,19 @@ bool vhost_vq_access_ok(struct vhost_virtqueue *vq); bool vhost_log_access_ok(struct vhost_dev *); int vhost_get_vq_desc(struct vhost_virtqueue *, - struct iovec iov[], unsigned int iov_count, + struct vhost_iov 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_viov(struct vhost_virtqueue *vq, + struct vhost_iov *viov, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num); +int vhost_get_vq_desc_viov_offset(struct vhost_virtqueue *vq, + struct vhost_iov *viov, + int offset, + 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); bool vhost_vq_is_setup(struct vhost_virtqueue *vq); @@ -207,7 +243,7 @@ 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); + struct vhost_iov *viov, int count); int vq_meta_prefetch(struct vhost_virtqueue *vq); struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type); diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index 938aefbc75ec..190e5a6ea045 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -158,14 +158,14 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, break; } - iov_len = iov_length(&vq->iov[out], in); + iov_len = vhost_iov_length(vq, &vq->iov[out], in); if (iov_len < sizeof(pkt->hdr)) { virtio_transport_free_pkt(pkt); vq_err(vq, "Buffer len [%zu] too small\n", iov_len); break; } - iov_iter_init(&iov_iter, READ, &vq->iov[out], in, iov_len); + vhost_iov_iter_init(vq, &iov_iter, READ, &vq->iov[out], in, iov_len); payload_len = pkt->len - pkt->off; /* If the packet is greater than the space available in the @@ -370,8 +370,8 @@ vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, if (!pkt) return NULL; - len = iov_length(vq->iov, out); - iov_iter_init(&iov_iter, WRITE, vq->iov, out, len); + len = vhost_iov_length(vq, vq->iov, out); + vhost_iov_iter_init(vq, &iov_iter, WRITE, vq->iov, out, len); nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); if (nbytes != sizeof(pkt->hdr)) {