Messages in this thread | | | Subject | Re: [RFC 2/2] vhost: IFC VF vdpa layer | From | Jason Wang <> | Date | Wed, 16 Oct 2019 18:19:26 +0800 |
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On 2019/10/16 上午9:30, Zhu Lingshan wrote: > This commit introduced IFC VF operations for vdpa, which complys to > vhost_mdev interfaces, handles IFC VF initialization, > configuration and removal. > > Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com> > --- > drivers/vhost/ifcvf/ifcvf_main.c | 541 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 541 insertions(+) > create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c > > diff --git a/drivers/vhost/ifcvf/ifcvf_main.c b/drivers/vhost/ifcvf/ifcvf_main.c > new file mode 100644 > index 000000000000..c48a29969a85 > --- /dev/null > +++ b/drivers/vhost/ifcvf/ifcvf_main.c > @@ -0,0 +1,541 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2019 Intel Corporation. > + */ > + > +#include <linux/interrupt.h> > +#include <linux/module.h> > +#include <linux/mdev.h> > +#include <linux/pci.h> > +#include <linux/sysfs.h> > + > +#include "ifcvf_base.h" > + > +#define VERSION_STRING "0.1" > +#define DRIVER_AUTHOR "Intel Corporation" > +#define IFCVF_DRIVER_NAME "ifcvf" > + > +static irqreturn_t ifcvf_intr_handler(int irq, void *arg) > +{ > + struct vring_info *vring = arg; > + > + if (vring->cb.callback) > + return vring->cb.callback(vring->cb.private); > + > + return IRQ_HANDLED; > +} > + > +static u64 ifcvf_mdev_get_features(struct mdev_device *mdev) > +{ > + return IFC_SUPPORTED_FEATURES;
I would expect this should be done by querying the hw. Or IFC VF can't get any update through its firmware?
> +} > + > +static int ifcvf_mdev_set_features(struct mdev_device *mdev, u64 features) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + vf->req_features = features; > + > + return 0; > +} > + > +static u64 ifcvf_mdev_get_vq_state(struct mdev_device *mdev, u16 qid) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + return vf->vring[qid].last_avail_idx;
Does this really work? I'd expect it should be fetched from hw since it's an internal state.
> +} > + > +static int ifcvf_mdev_set_vq_state(struct mdev_device *mdev, u16 qid, u64 num) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + vf->vring[qid].last_used_idx = num;
I fail to understand why last_used_idx is needed. It looks to me the used idx in the used ring is sufficient.
> + vf->vring[qid].last_avail_idx = num;
Do we need a synchronization with hw immediately here?
> + > + return 0; > +} > + > +static int ifcvf_mdev_set_vq_address(struct mdev_device *mdev, u16 idx, > + u64 desc_area, u64 driver_area, > + u64 device_area) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + vf->vring[idx].desc = desc_area; > + vf->vring[idx].avail = driver_area; > + vf->vring[idx].used = device_area; > + > + return 0; > +} > + > +static void ifcvf_mdev_set_vq_num(struct mdev_device *mdev, u16 qid, u32 num) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + vf->vring[qid].size = num; > +} > + > +static void ifcvf_mdev_set_vq_ready(struct mdev_device *mdev, > + u16 qid, bool ready) > +{ > + > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + vf->vring[qid].ready = ready; > +} > + > +static bool ifcvf_mdev_get_vq_ready(struct mdev_device *mdev, u16 qid) > +{ > + > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + return vf->vring[qid].ready; > +} > + > +static void ifcvf_mdev_set_vq_cb(struct mdev_device *mdev, u16 idx, > + struct virtio_mdev_callback *cb) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + vf->vring[idx].cb = *cb; > +} > + > +static void ifcvf_mdev_kick_vq(struct mdev_device *mdev, u16 idx) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + ifcvf_notify_queue(vf, idx); > +} > + > +static u8 ifcvf_mdev_get_status(struct mdev_device *mdev) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + return vf->status; > +} > + > +static u32 ifcvf_mdev_get_generation(struct mdev_device *mdev) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + return vf->generation; > +} > + > +static int ifcvf_mdev_get_version(struct mdev_device *mdev) > +{ > + return VIRTIO_MDEV_VERSION; > +} > + > +static u32 ifcvf_mdev_get_device_id(struct mdev_device *mdev) > +{ > + return IFCVF_DEVICE_ID; > +} > + > +static u32 ifcvf_mdev_get_vendor_id(struct mdev_device *mdev) > +{ > + return IFCVF_VENDOR_ID; > +} > + > +static u16 ifcvf_mdev_get_vq_align(struct mdev_device *mdev) > +{ > + return IFCVF_QUEUE_ALIGNMENT; > +} > + > +static int ifcvf_start_datapath(void *private) > +{ > + int i, ret; > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private); > + > + for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) { > + if (!vf->vring[i].ready) > + break;
Looks like error should be returned here?
> + > + if (!vf->vring[i].size) > + break; > + > + if (!vf->vring[i].desc || !vf->vring[i].avail || > + !vf->vring[i].used) > + break; > + } > + vf->nr_vring = i; > + > + ret = ifcvf_start_hw(vf); > + return ret; > +} > + > +static int ifcvf_stop_datapath(void *private) > +{ > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private); > + int i; > + > + for (i = 0; i < IFCVF_MAX_QUEUES; i++) > + vf->vring[i].cb.callback = NULL;
Any synchronization is needed for the vq irq handler?
> + > + ifcvf_stop_hw(vf); > + > + return 0; > +} > + > +static void ifcvf_reset_vring(struct ifcvf_adapter *adapter) > +{ > + int i; > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) { > + vf->vring[i].last_used_idx = 0; > + vf->vring[i].last_avail_idx = 0; > + vf->vring[i].desc = 0; > + vf->vring[i].avail = 0; > + vf->vring[i].used = 0; > + vf->vring[i].ready = 0; > + vf->vring->cb.callback = NULL; > + vf->vring->cb.private = NULL; > + } > +} > + > +static void ifcvf_mdev_set_status(struct mdev_device *mdev, u8 status) > +{ > + struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev); > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + > + vf->status = status; > + > + if (status == 0) { > + ifcvf_stop_datapath(adapter); > + ifcvf_reset_vring(adapter); > + return; > + } > + > + if (status & VIRTIO_CONFIG_S_DRIVER_OK) { > + ifcvf_start_datapath(adapter); > + return; > + } > +} > + > +static u16 ifcvf_mdev_get_queue_max(struct mdev_device *mdev) > +{ > + return IFCVF_MAX_QUEUES;
The name is confusing, it was used to return the maximum queue size. In new version of virtio-mdev, the callback was renamed as get_vq_num_max().
> +} > + > +static struct virtio_mdev_device_ops ifc_mdev_ops = { > + .get_features = ifcvf_mdev_get_features, > + .set_features = ifcvf_mdev_set_features, > + .get_status = ifcvf_mdev_get_status, > + .set_status = ifcvf_mdev_set_status, > + .get_queue_max = ifcvf_mdev_get_queue_max, > + .get_vq_state = ifcvf_mdev_get_vq_state, > + .set_vq_state = ifcvf_mdev_set_vq_state, > + .set_vq_cb = ifcvf_mdev_set_vq_cb, > + .set_vq_ready = ifcvf_mdev_set_vq_ready, > + .get_vq_ready = ifcvf_mdev_get_vq_ready, > + .set_vq_num = ifcvf_mdev_set_vq_num, > + .set_vq_address = ifcvf_mdev_set_vq_address, > + .kick_vq = ifcvf_mdev_kick_vq, > + .get_generation = ifcvf_mdev_get_generation, > + .get_version = ifcvf_mdev_get_version, > + .get_device_id = ifcvf_mdev_get_device_id, > + .get_vendor_id = ifcvf_mdev_get_vendor_id, > + .get_vq_align = ifcvf_mdev_get_vq_align, > +};
set_config/get_config is missing. It looks to me they are not hard, just implementing the access to dev_cfg. It's key to make kernel virtio driver to work.
And in the new version of virito-mdev, features like _F_LOG_ALL should be advertised through get_mdev_features.
> + > +static int ifcvf_init_msix(struct ifcvf_adapter *adapter) > +{ > + int vector, i, ret, irq; > + struct pci_dev *pdev = to_pci_dev(adapter->dev); > + struct ifcvf_hw *vf = &adapter->vf; > + > + ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR, > + IFCVF_MAX_INTR, PCI_IRQ_MSIX); > + if (ret < 0) { > + IFC_ERR(adapter->dev, "Failed to alloc irq vectors.\n"); > + return ret; > + } > + > + for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) { > + vector = i + IFCVF_MSI_QUEUE_OFF; > + irq = pci_irq_vector(pdev, vector); > + ret = request_irq(irq, ifcvf_intr_handler, 0, > + pci_name(pdev), &vf->vring[i]); > + if (ret) { > + IFC_ERR(adapter->dev, > + "Failed to request irq for vq %d.\n", i); > + return ret; > + } > + }
Do we need to provide fallback when we can't do per vq MSIX?
> + > + return 0; > +} > + > +static void ifcvf_destroy_adapter(struct ifcvf_adapter *adapter) > +{ > + int i, vector, irq; > + struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter); > + struct pci_dev *pdev = to_pci_dev(adapter->dev); > + > + for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) { > + vector = i + IFCVF_MSI_QUEUE_OFF; > + irq = pci_irq_vector(pdev, vector); > + free_irq(irq, &vf->vring[i]); > + } > +} > + > +static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf) > +{ > + const char *name = "vhost accelerator (virtio ring compatible)"; > + > + return sprintf(buf, "%s\n", name); > +} > +MDEV_TYPE_ATTR_RO(name); > + > +static ssize_t device_api_show(struct kobject *kobj, struct device *dev, > + char *buf) > +{ > + return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING); > +} > +MDEV_TYPE_ATTR_RO(device_api); > + > +static ssize_t available_instances_show(struct kobject *kobj, > + struct device *dev, char *buf) > +{ > + struct pci_dev *pdev = to_pci_dev(dev); > + struct ifcvf_adapter *adapter = pci_get_drvdata(pdev); > + > + return sprintf(buf, "%d\n", adapter->mdev_count); > +} > + > +MDEV_TYPE_ATTR_RO(available_instances); > + > +static ssize_t type_show(struct kobject *kobj, > + struct device *dev, char *buf) > +{ > + return sprintf(buf, "%s\n", "net"); > +} > + > +MDEV_TYPE_ATTR_RO(type); > + > + > +static struct attribute *mdev_types_attrs[] = { > + &mdev_type_attr_name.attr, > + &mdev_type_attr_device_api.attr, > + &mdev_type_attr_available_instances.attr, > + &mdev_type_attr_type.attr, > + NULL, > +}; > + > +static struct attribute_group mdev_type_group = { > + .name = "vdpa_virtio",
To be consistent, it should be "vhost" or "virtio".
> + .attrs = mdev_types_attrs, > +}; > + > +static struct attribute_group *mdev_type_groups[] = { > + &mdev_type_group, > + NULL, > +}; > + > +const struct attribute_group *mdev_dev_groups[] = { > + NULL, > +}; > + > +static int ifcvf_mdev_create(struct kobject *kobj, struct mdev_device *mdev) > +{ > + struct device *dev = mdev_parent_dev(mdev); > + struct pci_dev *pdev = to_pci_dev(dev); > + struct ifcvf_adapter *adapter = pci_get_drvdata(pdev); > + int ret = 0; > + > + mutex_lock(&adapter->mdev_lock); > + > + if (adapter->mdev_count < 1) { > + ret = -EINVAL; > + goto out; > + } > + > + mdev_set_class_id(mdev, MDEV_ID_VHOST); > + mdev_set_dev_ops(mdev, &ifc_mdev_ops); > + > + mdev_set_drvdata(mdev, adapter); > + mdev_set_iommu_device(mdev_dev(mdev), dev); > + > + INIT_LIST_HEAD(&adapter->dma_maps); > + adapter->mdev_count--; > + > +out: > + mutex_unlock(&adapter->mdev_lock); > + return ret; > +} > + > +static int ifcvf_mdev_remove(struct mdev_device *mdev) > +{ > + struct device *dev = mdev_parent_dev(mdev); > + struct pci_dev *pdev = to_pci_dev(dev); > + struct ifcvf_adapter *adapter = pci_get_drvdata(pdev); > + > + mutex_lock(&adapter->mdev_lock); > + adapter->mdev_count++; > + mutex_unlock(&adapter->mdev_lock); > + > + return 0; > +} > + > +static struct mdev_parent_ops ifcvf_mdev_fops = { > + .owner = THIS_MODULE, > + .supported_type_groups = mdev_type_groups, > + .mdev_attr_groups = mdev_dev_groups, > + .create = ifcvf_mdev_create, > + .remove = ifcvf_mdev_remove, > +}; > + > +static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id) > +{ > + struct device *dev = &pdev->dev; > + struct ifcvf_adapter *adapter; > + struct ifcvf_hw *vf; > + int ret, i; > + > + adapter = kzalloc(sizeof(struct ifcvf_adapter), GFP_KERNEL); > + if (adapter == NULL) { > + ret = -ENOMEM; > + goto fail; > + } > + > + mutex_init(&adapter->mdev_lock); > + adapter->mdev_count = 1;
So this is per VF based vDPA implementation, which seems not convenient for management. Anyhow we can control the creation in PF?
Thanks
> + adapter->dev = dev; > + > + pci_set_drvdata(pdev, adapter); > + > + ret = pci_enable_device(pdev); > + if (ret) { > + IFC_ERR(adapter->dev, "Failed to enable device.\n"); > + goto free_adapter; > + } > + > + ret = pci_request_regions(pdev, IFCVF_DRIVER_NAME); > + if (ret) { > + IFC_ERR(adapter->dev, "Failed to request MMIO region.\n"); > + goto disable_device; > + } > + > + pci_set_master(pdev); > + > + ret = ifcvf_init_msix(adapter); > + if (ret) { > + IFC_ERR(adapter->dev, "Failed to initialize MSIX.\n"); > + goto free_msix; > + } > + > + vf = &adapter->vf; > + for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) { > + vf->mem_resource[i].phys_addr = pci_resource_start(pdev, i); > + vf->mem_resource[i].len = pci_resource_len(pdev, i); > + if (!vf->mem_resource[i].len) { > + vf->mem_resource[i].addr = NULL; > + continue; > + } > + > + vf->mem_resource[i].addr = pci_iomap_range(pdev, i, 0, > + vf->mem_resource[i].len); > + if (!vf->mem_resource[i].addr) { > + IFC_ERR(adapter->dev, "Failed to map IO resource %d\n", > + i); > + return -1; > + } > + } > + > + if (ifcvf_init_hw(vf, pdev) < 0) > + return -1; > + > + ret = mdev_register_device(dev, &ifcvf_mdev_fops); > + if (ret) { > + IFC_ERR(adapter->dev, "Failed to register mdev device\n"); > + goto destroy_adapter; > + } > + > + return 0; > + > +destroy_adapter: > + ifcvf_destroy_adapter(adapter); > +free_msix: > + pci_free_irq_vectors(pdev); > + pci_release_regions(pdev); > +disable_device: > + pci_disable_device(pdev); > +free_adapter: > + kfree(adapter); > +fail: > + return ret; > +} > + > +static void ifcvf_remove(struct pci_dev *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct ifcvf_adapter *adapter = pci_get_drvdata(pdev); > + struct ifcvf_hw *vf; > + int i; > + > + mdev_unregister_device(dev); > + > + vf = &adapter->vf; > + for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) { > + if (vf->mem_resource[i].addr) { > + pci_iounmap(pdev, vf->mem_resource[i].addr); > + vf->mem_resource[i].addr = NULL; > + } > + } > + > + ifcvf_destroy_adapter(adapter); > + pci_free_irq_vectors(pdev); > + > + pci_release_regions(pdev); > + pci_disable_device(pdev); > + > + kfree(adapter); > +} > + > +static struct pci_device_id ifcvf_pci_ids[] = { > + { PCI_DEVICE_SUB(IFCVF_VENDOR_ID, > + IFCVF_DEVICE_ID, > + IFCVF_SUBSYS_VENDOR_ID, > + IFCVF_SUBSYS_DEVICE_ID) }, > + { 0 }, > +}; > +MODULE_DEVICE_TABLE(pci, ifcvf_pci_ids); > + > +static struct pci_driver ifcvf_driver = { > + .name = IFCVF_DRIVER_NAME, > + .id_table = ifcvf_pci_ids, > + .probe = ifcvf_probe, > + .remove = ifcvf_remove, > +}; > + > +static int __init ifcvf_init_module(void) > +{ > + int ret; > + > + ret = pci_register_driver(&ifcvf_driver); > + return ret; > +} > + > +static void __exit ifcvf_exit_module(void) > +{ > + pci_unregister_driver(&ifcvf_driver); > +} > + > +module_init(ifcvf_init_module); > +module_exit(ifcvf_exit_module); > + > +MODULE_LICENSE("GPL v2"); > +MODULE_VERSION(VERSION_STRING); > +MODULE_AUTHOR(DRIVER_AUTHOR);
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