From 87308b5370274d2d6520a0ed448e2f2b43d6debc Mon Sep 17 00:00:00 2001 From: Yuanhan Liu Date: Thu, 12 Nov 2015 12:10:41 +0800 Subject: [PATCH] vhost: reset device properly Currently, we reset all fields of a device to zero when reset happens, which is wrong, since for some fields like device_fh, ifname, and virt_qp_nb, they should be same and be kept after reset until the device is removed. And this is what's the new helper function reset_device() for. And use rte_zmalloc() instead of rte_malloc, so that we could avoid init_device(), which basically dose zero reset only so far. Hence, init_device() is dropped in this patch. This patch also removes a hack of using the offset a specific field (which is virtqueue now) inside of `virtio_net' structure to do reset, which could be broken easily if someone changed the field order without caution. Cc: Tetsuya Mukawa Cc: Huawei Xie Signed-off-by: Yuanhan Liu Acked-by: Rich Lane --- lib/librte_vhost/virtio-net.c | 27 ++++++++++----------------- 1 file changed, 10 insertions(+), 17 deletions(-) diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c index 39a6a5e8de..cc917dabe5 100644 --- a/lib/librte_vhost/virtio-net.c +++ b/lib/librte_vhost/virtio-net.c @@ -204,6 +204,7 @@ cleanup_device(struct virtio_net *dev) munmap((void *)(uintptr_t)dev->mem->mapped_address, (size_t)dev->mem->mapped_size); free(dev->mem); + dev->mem = NULL; } for (i = 0; i < dev->virt_qp_nb; i++) { @@ -306,20 +307,18 @@ alloc_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx) } /* - * Initialise all variables in device structure. + * Reset some variables in device structure, while keeping few + * others untouched, such as device_fh, ifname, virt_qp_nb: they + * should be same unless the device is removed. */ static void -init_device(struct virtio_net *dev) +reset_device(struct virtio_net *dev) { - int vq_offset; uint32_t i; - /* - * Virtqueues have already been malloced so - * we don't want to set them to NULL. - */ - vq_offset = offsetof(struct virtio_net, virtqueue); - memset(dev, 0, vq_offset); + dev->features = 0; + dev->protocol_features = 0; + dev->flags = 0; for (i = 0; i < dev->virt_qp_nb; i++) init_vring_queue_pair(dev, i); @@ -336,7 +335,7 @@ new_device(struct vhost_device_ctx ctx) struct virtio_net_config_ll *new_ll_dev; /* Setup device and virtqueues. */ - new_ll_dev = rte_malloc(NULL, sizeof(struct virtio_net_config_ll), 0); + new_ll_dev = rte_zmalloc(NULL, sizeof(struct virtio_net_config_ll), 0); if (new_ll_dev == NULL) { RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev.\n", @@ -344,9 +343,6 @@ new_device(struct vhost_device_ctx ctx) return -1; } - /* Initialise device and virtqueues. */ - init_device(&new_ll_dev->dev); - new_ll_dev->next = NULL; /* Add entry to device configuration linked list. */ @@ -430,7 +426,6 @@ static int reset_owner(struct vhost_device_ctx ctx) { struct virtio_net *dev; - uint64_t device_fh; dev = get_device(ctx); if (dev == NULL) @@ -439,10 +434,8 @@ reset_owner(struct vhost_device_ctx ctx) if (dev->flags & VIRTIO_DEV_RUNNING) notify_ops->destroy_device(dev); - device_fh = dev->device_fh; cleanup_device(dev); - init_device(dev); - dev->device_fh = device_fh; + reset_device(dev); return 0; } -- 2.20.1