Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757842AbaGAKrr (ORCPT ); Tue, 1 Jul 2014 06:47:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12071 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757788AbaGAKro (ORCPT ); Tue, 1 Jul 2014 06:47:44 -0400 Date: Tue, 1 Jul 2014 13:49:41 +0300 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: Rusty Russell , virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, Jason Wang Subject: [PATCH RFC 2/2] vhost: support urgent descriptors Message-ID: <1404203661-7521-2-git-send-email-mst@redhat.com> References: <1404203661-7521-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1404203661-7521-1-git-send-email-mst@redhat.com> X-Mutt-Fcc: =sent Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.h | 19 +++++++++++++------ drivers/vhost/net.c | 30 +++++++++++++++++++++--------- drivers/vhost/scsi.c | 23 +++++++++++++++-------- drivers/vhost/test.c | 5 +++-- drivers/vhost/vhost.c | 23 ++++++++++++++++------- 5 files changed, 68 insertions(+), 32 deletions(-) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 3eda654..61ca542 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -96,6 +96,9 @@ struct vhost_virtqueue { /* Last used index value we have signalled on */ bool signalled_used_valid; + /* Urgent descriptor was used */ + bool urgent; + /* Log writes to used structure. */ bool log_used; u64 log_addr; @@ -138,20 +141,24 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp); int vhost_vq_access_ok(struct vhost_virtqueue *vq); int vhost_log_access_ok(struct vhost_dev *); -int vhost_get_vq_desc(struct vhost_virtqueue *, +int vhost_get_vq_desc(struct vhost_virtqueue *, bool *urgent, 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_vq_desc(struct vhost_virtqueue *, int n); int vhost_init_used(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, - unsigned count); -void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *, +int vhost_add_used(struct vhost_virtqueue *, bool urgent, + unsigned int head, int len); +int vhost_add_used_n(struct vhost_virtqueue *, bool urgent, + struct vring_used_elem *heads, unsigned count); +void vhost_add_used_and_signal(struct vhost_dev *, + struct vhost_virtqueue *, + bool urgent, 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); + bool urgent, + struct vring_used_elem *heads, unsigned count); void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *); void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *); bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *); diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 8dae2f7..5f0567f 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -48,9 +48,11 @@ 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 3 +#define VHOST_DMA_FAILED_LEN 4 /* Lower device DMA done */ -#define VHOST_DMA_DONE_LEN 2 +#define VHOST_DMA_DONE_LEN 3 +/* Lower device DMA in progress, urgent bit set */ +#define VHOST_DMA_URGENT 2 /* Lower device DMA in progress */ #define VHOST_DMA_IN_PROGRESS 1 /* Buffer unused */ @@ -284,11 +286,13 @@ static void vhost_zerocopy_signal_used(struct vhost_net *net, container_of(vq, struct vhost_net_virtqueue, vq); int i, add; int j = 0; + bool urgent = false; for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) { if (vq->heads[i].len == VHOST_DMA_FAILED_LEN) vhost_net_tx_err(net); if (VHOST_DMA_IS_DONE(vq->heads[i].len)) { + urgent = urgent || vq->heads[i].len == VHOST_DMA_URGENT; vq->heads[i].len = VHOST_DMA_CLEAR_LEN; ++j; } else @@ -296,7 +300,7 @@ static void vhost_zerocopy_signal_used(struct vhost_net *net, } while (j) { add = min(UIO_MAXIOV - nvq->done_idx, j); - vhost_add_used_and_signal_n(vq->dev, vq, + vhost_add_used_and_signal_n(vq->dev, vq, urgent, &vq->heads[nvq->done_idx], add); nvq->done_idx = (nvq->done_idx + add) % UIO_MAXIOV; j -= add; @@ -363,6 +367,7 @@ static void handle_tx(struct vhost_net *net) zcopy = nvq->ubufs; for (;;) { + bool urgent; /* Release DMAs done buffers first */ if (zcopy) vhost_zerocopy_signal_used(net, vq); @@ -374,7 +379,7 @@ static void handle_tx(struct vhost_net *net) % UIO_MAXIOV == nvq->done_idx)) break; - head = vhost_get_vq_desc(vq, vq->iov, + head = vhost_get_vq_desc(vq, &urgent, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); @@ -417,7 +422,8 @@ static void handle_tx(struct vhost_net *net) ubuf = nvq->ubuf_info + nvq->upend_idx; vq->heads[nvq->upend_idx].id = head; - vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; + vq->heads[nvq->upend_idx].len = urgent ? + VHOST_DMA_IN_PROGRESS : VHOST_DMA_URGENT; ubuf->callback = vhost_zerocopy_callback; ubuf->ctx = nvq->ubufs; ubuf->desc = nvq->upend_idx; @@ -445,7 +451,7 @@ static void handle_tx(struct vhost_net *net) pr_debug("Truncated TX packet: " " len %d != %zd\n", err, len); if (!zcopy_used) - vhost_add_used_and_signal(&net->dev, vq, head, 0); + vhost_add_used_and_signal(&net->dev, vq, urgent, head, 0); else vhost_zerocopy_signal_used(net, vq); total_len += len; @@ -488,6 +494,7 @@ static int peek_head_len(struct sock *sk) * returns number of buffer heads allocated, negative on error */ static int get_rx_bufs(struct vhost_virtqueue *vq, + bool *urgentp, struct vring_used_elem *heads, int datalen, unsigned *iovcount, @@ -502,11 +509,13 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, int r, nlogs = 0; while (datalen > 0 && headcount < quota) { + bool urgent; + if (unlikely(seg >= UIO_MAXIOV)) { r = -ENOBUFS; goto err; } - r = vhost_get_vq_desc(vq, vq->iov + seg, + r = vhost_get_vq_desc(vq, &urgent, vq->iov + seg, ARRAY_SIZE(vq->iov) - seg, &out, &in, log, log_num); if (unlikely(r < 0)) @@ -527,6 +536,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, nlogs += *log_num; log += *log_num; } + *urgentp = *urgentp || urgent; heads[headcount].id = d; heads[headcount].len = iov_length(vq->iov + seg, in); datalen -= heads[headcount].len; @@ -590,9 +600,11 @@ static void handle_rx(struct vhost_net *net) mergeable = vhost_has_feature(vq, VIRTIO_NET_F_MRG_RXBUF); while ((sock_len = peek_head_len(sock->sk))) { + bool urgent; + sock_len += sock_hlen; vhost_len = sock_len + vhost_hlen; - headcount = get_rx_bufs(vq, vq->heads, vhost_len, + headcount = get_rx_bufs(vq, &urgent, vq->heads, vhost_len, &in, vq_log, &log, likely(mergeable) ? UIO_MAXIOV : 1); /* On error, stop handling until the next kick. */ @@ -654,7 +666,7 @@ static void handle_rx(struct vhost_net *net) vhost_discard_vq_desc(vq, headcount); break; } - vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, + vhost_add_used_and_signal_n(&net->dev, vq, urgent, vq->heads, headcount); if (unlikely(vq_log)) vhost_log_write(vq, vq_log, log, vhost_len); diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 69906ca..0a7e5bc 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -72,6 +72,8 @@ struct tcm_vhost_cmd { int tvc_vq_desc; /* virtio-scsi initiator task attribute */ int tvc_task_attr; + /* Descriptor urgent? */ + bool tvc_vq_desc_urgent; /* virtio-scsi initiator data direction */ enum dma_data_direction tvc_data_direction; /* Expected data transfer length from virtio-scsi header */ @@ -606,6 +608,7 @@ tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt) struct virtio_scsi_event __user *eventp; unsigned out, in; int head, ret; + bool urgent; if (!vq->private_data) { vs->vs_events_missed = true; @@ -614,7 +617,7 @@ tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt) again: vhost_disable_notify(&vs->dev, vq); - head = vhost_get_vq_desc(vq, vq->iov, + head = vhost_get_vq_desc(vq, &urgent, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); if (head < 0) { @@ -643,7 +646,7 @@ again: eventp = vq->iov[out].iov_base; ret = __copy_to_user(eventp, event, sizeof(*event)); if (!ret) - vhost_add_used_and_signal(&vs->dev, vq, head, 0); + vhost_add_used_and_signal(&vs->dev, vq, urgent, head, 0); else vq_err(vq, "Faulted on tcm_vhost_send_event\n"); } @@ -704,7 +707,8 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work) ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp)); if (likely(ret == 0)) { struct vhost_scsi_virtqueue *q; - vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0); + vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc_urgent, + cmd->tvc_vq_desc, 0); q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq); vq = q - vs->vqs; __set_bit(vq, signal); @@ -947,6 +951,7 @@ static void tcm_vhost_submission_work(struct work_struct *work) static void vhost_scsi_send_bad_target(struct vhost_scsi *vs, struct vhost_virtqueue *vq, + bool urgent, int head, unsigned out) { struct virtio_scsi_cmd_resp __user *resp; @@ -958,7 +963,7 @@ vhost_scsi_send_bad_target(struct vhost_scsi *vs, resp = vq->iov[out].iov_base; ret = __copy_to_user(resp, &rsp, sizeof(rsp)); if (!ret) - vhost_add_used_and_signal(&vs->dev, vq, head, 0); + vhost_add_used_and_signal(&vs->dev, vq, urgent, head, 0); else pr_err("Faulted on virtio_scsi_cmd_resp\n"); } @@ -980,6 +985,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) u8 *target, *lunp, task_attr; bool hdr_pi; void *req, *cdb; + bool urgent; mutex_lock(&vq->mutex); /* @@ -993,7 +999,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) vhost_disable_notify(&vs->dev, vq); for (;;) { - head = vhost_get_vq_desc(vq, vq->iov, + head = vhost_get_vq_desc(vq, &urgent, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n", @@ -1067,7 +1073,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) /* virtio-scsi spec requires byte 0 of the lun to be 1 */ if (unlikely(*lunp != 1)) { - vhost_scsi_send_bad_target(vs, vq, head, out); + vhost_scsi_send_bad_target(vs, vq, urgent, head, out); continue; } @@ -1075,7 +1081,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) /* Target does not exist, fail the request */ if (unlikely(!tpg)) { - vhost_scsi_send_bad_target(vs, vq, head, out); + vhost_scsi_send_bad_target(vs, vq, urgent, head, out); continue; } @@ -1187,6 +1193,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) * tcm_vhost_queue_data_in() and tcm_vhost_queue_status() */ cmd->tvc_vq_desc = head; + cmd->tvc_vq_desc_urgent = urgent; /* * Dispatch tv_cmd descriptor for cmwq execution in process * context provided by tcm_vhost_workqueue. This also ensures @@ -1203,7 +1210,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) err_free: vhost_scsi_free_cmd(cmd); err_cmd: - vhost_scsi_send_bad_target(vs, vq, head, out); + vhost_scsi_send_bad_target(vs, vq, urgent, head, out); out: mutex_unlock(&vq->mutex); } diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c index d9c501e..757f3a2 100644 --- a/drivers/vhost/test.c +++ b/drivers/vhost/test.c @@ -42,6 +42,7 @@ static void handle_vq(struct vhost_test *n) int head; size_t len, total_len = 0; void *private; + bool urgent; mutex_lock(&vq->mutex); private = vq->private_data; @@ -53,7 +54,7 @@ static void handle_vq(struct vhost_test *n) vhost_disable_notify(&n->dev, vq); for (;;) { - head = vhost_get_vq_desc(vq, vq->iov, + head = vhost_get_vq_desc(vq, &urgent, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); @@ -79,7 +80,7 @@ static void handle_vq(struct vhost_test *n) vq_err(vq, "Unexpected 0 len for TX\n"); break; } - vhost_add_used_and_signal(&n->dev, vq, head, 0); + vhost_add_used_and_signal(&n->dev, vq, urgent, head, 0); total_len += len; if (unlikely(total_len >= VHOST_TEST_WEIGHT)) { vhost_poll_queue(&vq->poll); diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index c90f437..0dcd9d2 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -186,6 +186,7 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->last_used_idx = 0; vq->signalled_used = 0; vq->signalled_used_valid = false; + vq->urgent = false; vq->used_flags = 0; vq->log_used = false; vq->log_addr = -1ull; @@ -1201,7 +1202,7 @@ static int get_indirect(struct vhost_virtqueue *vq, * 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, +int vhost_get_vq_desc(struct vhost_virtqueue *vq, bool *urgent, struct iovec iov[], unsigned int iov_size, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num) @@ -1251,6 +1252,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* When we start there are none of either input nor output. */ *out_num = *in_num = 0; + *urgent = false; if (unlikely(log)) *log_num = 0; @@ -1274,6 +1276,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->desc + i); return -EFAULT; } + if (desc.flags & VRING_DESC_F_URGENT) + *urgent = true; if (desc.flags & VRING_DESC_F_INDIRECT) { ret = get_indirect(vq, iov, iov_size, out_num, in_num, @@ -1333,11 +1337,11 @@ EXPORT_SYMBOL_GPL(vhost_discard_vq_desc); /* After we've used one of their buffers, we tell them about it. We'll then * want to notify the guest, using eventfd. */ -int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) +int vhost_add_used(struct vhost_virtqueue *vq, bool urgent, unsigned int head, int len) { struct vring_used_elem heads = { head, len }; - return vhost_add_used_n(vq, &heads, 1); + return vhost_add_used_n(vq, urgent, &heads, 1); } EXPORT_SYMBOL_GPL(vhost_add_used); @@ -1386,7 +1390,8 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, /* After we've used one of their buffers, we tell them about it. We'll then * want to notify the guest, using eventfd. */ -int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, +int vhost_add_used_n(struct vhost_virtqueue *vq, bool urgent, + struct vring_used_elem *heads, unsigned count) { int start, n, r; @@ -1416,6 +1421,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, if (vq->log_ctx) eventfd_signal(vq->log_ctx, 1); } + vq->urgent = vq->urgent || urgent; return r; } EXPORT_SYMBOL_GPL(vhost_add_used_n); @@ -1433,12 +1439,13 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) unlikely(vq->avail_idx == vq->last_avail_idx)) return true; - if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { + if (vq->urgent || !vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { __u16 flags; if (__get_user(flags, &vq->avail->flags)) { vq_err(vq, "Failed to get flags"); return true; } + vq->urgent = false; return !(flags & VRING_AVAIL_F_NO_INTERRUPT); } old = vq->signalled_used; @@ -1468,9 +1475,10 @@ EXPORT_SYMBOL_GPL(vhost_signal); /* And here's the combo meal deal. Supersize me! */ void vhost_add_used_and_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq, + bool urgent, unsigned int head, int len) { - vhost_add_used(vq, head, len); + vhost_add_used(vq, urgent, head, len); vhost_signal(dev, vq); } EXPORT_SYMBOL_GPL(vhost_add_used_and_signal); @@ -1478,9 +1486,10 @@ EXPORT_SYMBOL_GPL(vhost_add_used_and_signal); /* multi-buffer version of vhost_add_used_and_signal */ void vhost_add_used_and_signal_n(struct vhost_dev *dev, struct vhost_virtqueue *vq, + bool urgent, struct vring_used_elem *heads, unsigned count) { - vhost_add_used_n(vq, heads, count); + vhost_add_used_n(vq, urgent, heads, count); vhost_signal(dev, vq); } EXPORT_SYMBOL_GPL(vhost_add_used_and_signal_n); -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/