// SPDX-License-Identifier: GPL-2.0-only /* * vDPA bus. * * Copyright (c) 2020, Red Hat. All rights reserved. * Author: Jason Wang * */ #include #include #include #include #include #include #include static LIST_HEAD(mdev_head); /* A global mutex that protects vdpa management device and device level operations. */ static DEFINE_MUTEX(vdpa_dev_mutex); static DEFINE_IDA(vdpa_index_ida); static struct genl_family vdpa_nl_family; static int vdpa_dev_probe(struct device *d) { struct vdpa_device *vdev = dev_to_vdpa(d); struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver); int ret = 0; if (drv && drv->probe) ret = drv->probe(vdev); return ret; } static void vdpa_dev_remove(struct device *d) { struct vdpa_device *vdev = dev_to_vdpa(d); struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver); if (drv && drv->remove) drv->remove(vdev); } static struct bus_type vdpa_bus = { .name = "vdpa", .probe = vdpa_dev_probe, .remove = vdpa_dev_remove, }; static void vdpa_release_dev(struct device *d) { struct vdpa_device *vdev = dev_to_vdpa(d); const struct vdpa_config_ops *ops = vdev->config; if (ops->free) ops->free(vdev); ida_simple_remove(&vdpa_index_ida, vdev->index); kfree(vdev); } /** * __vdpa_alloc_device - allocate and initilaize a vDPA device * This allows driver to some prepartion after device is * initialized but before registered. * @parent: the parent device * @config: the bus operations that is supported by this device * @size: size of the parent structure that contains private data * @name: name of the vdpa device; optional. * @use_va: indicate whether virtual address must be used by this device * * Driver should use vdpa_alloc_device() wrapper macro instead of * using this directly. * * Return: Returns an error when parent/config/dma_dev is not set or fail to get * ida. */ struct vdpa_device *__vdpa_alloc_device(struct device *parent, const struct vdpa_config_ops *config, size_t size, const char *name, bool use_va) { struct vdpa_device *vdev; int err = -EINVAL; if (!config) goto err; if (!!config->dma_map != !!config->dma_unmap) goto err; /* It should only work for the device that use on-chip IOMMU */ if (use_va && !(config->dma_map || config->set_map)) goto err; err = -ENOMEM; vdev = kzalloc(size, GFP_KERNEL); if (!vdev) goto err; err = ida_alloc(&vdpa_index_ida, GFP_KERNEL); if (err < 0) goto err_ida; vdev->dev.bus = &vdpa_bus; vdev->dev.parent = parent; vdev->dev.release = vdpa_release_dev; vdev->index = err; vdev->config = config; vdev->features_valid = false; vdev->use_va = use_va; if (name) err = dev_set_name(&vdev->dev, "%s", name); else err = dev_set_name(&vdev->dev, "vdpa%u", vdev->index); if (err) goto err_name; device_initialize(&vdev->dev); return vdev; err_name: ida_simple_remove(&vdpa_index_ida, vdev->index); err_ida: kfree(vdev); err: return ERR_PTR(err); } EXPORT_SYMBOL_GPL(__vdpa_alloc_device); static int vdpa_name_match(struct device *dev, const void *data) { struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev); return (strcmp(dev_name(&vdev->dev), data) == 0); } static int __vdpa_register_device(struct vdpa_device *vdev, int nvqs) { struct device *dev; vdev->nvqs = nvqs; lockdep_assert_held(&vdpa_dev_mutex); dev = bus_find_device(&vdpa_bus, NULL, dev_name(&vdev->dev), vdpa_name_match); if (dev) { put_device(dev); return -EEXIST; } return device_add(&vdev->dev); } /** * _vdpa_register_device - register a vDPA device with vdpa lock held * Caller must have a succeed call of vdpa_alloc_device() before. * Caller must invoke this routine in the management device dev_add() * callback after setting up valid mgmtdev for this vdpa device. * @vdev: the vdpa device to be registered to vDPA bus * @nvqs: number of virtqueues supported by this device * * Return: Returns an error when fail to add device to vDPA bus */ int _vdpa_register_device(struct vdpa_device *vdev, int nvqs) { if (!vdev->mdev) return -EINVAL; return __vdpa_register_device(vdev, nvqs); } EXPORT_SYMBOL_GPL(_vdpa_register_device); /** * vdpa_register_device - register a vDPA device * Callers must have a succeed call of vdpa_alloc_device() before. * @vdev: the vdpa device to be registered to vDPA bus * @nvqs: number of virtqueues supported by this device * * Return: Returns an error when fail to add to vDPA bus */ int vdpa_register_device(struct vdpa_device *vdev, int nvqs) { int err; mutex_lock(&vdpa_dev_mutex); err = __vdpa_register_device(vdev, nvqs); mutex_unlock(&vdpa_dev_mutex); return err; } EXPORT_SYMBOL_GPL(vdpa_register_device); /** * _vdpa_unregister_device - unregister a vDPA device * Caller must invoke this routine as part of management device dev_del() * callback. * @vdev: the vdpa device to be unregisted from vDPA bus */ void _vdpa_unregister_device(struct vdpa_device *vdev) { lockdep_assert_held(&vdpa_dev_mutex); WARN_ON(!vdev->mdev); device_unregister(&vdev->dev); } EXPORT_SYMBOL_GPL(_vdpa_unregister_device); /** * vdpa_unregister_device - unregister a vDPA device * @vdev: the vdpa device to be unregisted from vDPA bus */ void vdpa_unregister_device(struct vdpa_device *vdev) { mutex_lock(&vdpa_dev_mutex); device_unregister(&vdev->dev); mutex_unlock(&vdpa_dev_mutex); } EXPORT_SYMBOL_GPL(vdpa_unregister_device); /** * __vdpa_register_driver - register a vDPA device driver * @drv: the vdpa device driver to be registered * @owner: module owner of the driver * * Return: Returns an err when fail to do the registration */ int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner) { drv->driver.bus = &vdpa_bus; drv->driver.owner = owner; return driver_register(&drv->driver); } EXPORT_SYMBOL_GPL(__vdpa_register_driver); /** * vdpa_unregister_driver - unregister a vDPA device driver * @drv: the vdpa device driver to be unregistered */ void vdpa_unregister_driver(struct vdpa_driver *drv) { driver_unregister(&drv->driver); } EXPORT_SYMBOL_GPL(vdpa_unregister_driver); /** * vdpa_mgmtdev_register - register a vdpa management device * * @mdev: Pointer to vdpa management device * vdpa_mgmtdev_register() register a vdpa management device which supports * vdpa device management. * Return: Returns 0 on success or failure when required callback ops are not * initialized. */ int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev) { if (!mdev->device || !mdev->ops || !mdev->ops->dev_add || !mdev->ops->dev_del) return -EINVAL; INIT_LIST_HEAD(&mdev->list); mutex_lock(&vdpa_dev_mutex); list_add_tail(&mdev->list, &mdev_head); mutex_unlock(&vdpa_dev_mutex); return 0; } EXPORT_SYMBOL_GPL(vdpa_mgmtdev_register); static int vdpa_match_remove(struct device *dev, void *data) { struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev); struct vdpa_mgmt_dev *mdev = vdev->mdev; if (mdev == data) mdev->ops->dev_del(mdev, vdev); return 0; } void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev) { mutex_lock(&vdpa_dev_mutex); list_del(&mdev->list); /* Filter out all the entries belong to this management device and delete it. */ bus_for_each_dev(&vdpa_bus, NULL, mdev, vdpa_match_remove); mutex_unlock(&vdpa_dev_mutex); } EXPORT_SYMBOL_GPL(vdpa_mgmtdev_unregister); static bool mgmtdev_handle_match(const struct vdpa_mgmt_dev *mdev, const char *busname, const char *devname) { /* Bus name is optional for simulated management device, so ignore the * device with bus if bus attribute is provided. */ if ((busname && !mdev->device->bus) || (!busname && mdev->device->bus)) return false; if (!busname && strcmp(dev_name(mdev->device), devname) == 0) return true; if (busname && (strcmp(mdev->device->bus->name, busname) == 0) && (strcmp(dev_name(mdev->device), devname) == 0)) return true; return false; } static struct vdpa_mgmt_dev *vdpa_mgmtdev_get_from_attr(struct nlattr **attrs) { struct vdpa_mgmt_dev *mdev; const char *busname = NULL; const char *devname; if (!attrs[VDPA_ATTR_MGMTDEV_DEV_NAME]) return ERR_PTR(-EINVAL); devname = nla_data(attrs[VDPA_ATTR_MGMTDEV_DEV_NAME]); if (attrs[VDPA_ATTR_MGMTDEV_BUS_NAME]) busname = nla_data(attrs[VDPA_ATTR_MGMTDEV_BUS_NAME]); list_for_each_entry(mdev, &mdev_head, list) { if (mgmtdev_handle_match(mdev, busname, devname)) return mdev; } return ERR_PTR(-ENODEV); } static int vdpa_nl_mgmtdev_handle_fill(struct sk_buff *msg, const struct vdpa_mgmt_dev *mdev) { if (mdev->device->bus && nla_put_string(msg, VDPA_ATTR_MGMTDEV_BUS_NAME, mdev->device->bus->name)) return -EMSGSIZE; if (nla_put_string(msg, VDPA_ATTR_MGMTDEV_DEV_NAME, dev_name(mdev->device))) return -EMSGSIZE; return 0; } static int vdpa_mgmtdev_fill(const struct vdpa_mgmt_dev *mdev, struct sk_buff *msg, u32 portid, u32 seq, int flags) { u64 supported_classes = 0; void *hdr; int i = 0; int err; hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, VDPA_CMD_MGMTDEV_NEW); if (!hdr) return -EMSGSIZE; err = vdpa_nl_mgmtdev_handle_fill(msg, mdev); if (err) goto msg_err; while (mdev->id_table[i].device) { supported_classes |= BIT(mdev->id_table[i].device); i++; } if (nla_put_u64_64bit(msg, VDPA_ATTR_MGMTDEV_SUPPORTED_CLASSES, supported_classes, VDPA_ATTR_UNSPEC)) { err = -EMSGSIZE; goto msg_err; } genlmsg_end(msg, hdr); return 0; msg_err: genlmsg_cancel(msg, hdr); return err; } static int vdpa_nl_cmd_mgmtdev_get_doit(struct sk_buff *skb, struct genl_info *info) { struct vdpa_mgmt_dev *mdev; struct sk_buff *msg; int err; msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!msg) return -ENOMEM; mutex_lock(&vdpa_dev_mutex); mdev = vdpa_mgmtdev_get_from_attr(info->attrs); if (IS_ERR(mdev)) { mutex_unlock(&vdpa_dev_mutex); NL_SET_ERR_MSG_MOD(info->extack, "Fail to find the specified mgmt device"); err = PTR_ERR(mdev); goto out; } err = vdpa_mgmtdev_fill(mdev, msg, info->snd_portid, info->snd_seq, 0); mutex_unlock(&vdpa_dev_mutex); if (err) goto out; err = genlmsg_reply(msg, info); return err; out: nlmsg_free(msg); return err; } static int vdpa_nl_cmd_mgmtdev_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb) { struct vdpa_mgmt_dev *mdev; int start = cb->args[0]; int idx = 0; int err; mutex_lock(&vdpa_dev_mutex); list_for_each_entry(mdev, &mdev_head, list) { if (idx < start) { idx++; continue; } err = vdpa_mgmtdev_fill(mdev, msg, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI); if (err) goto out; idx++; } out: mutex_unlock(&vdpa_dev_mutex); cb->args[0] = idx; return msg->len; } static int vdpa_nl_cmd_dev_add_set_doit(struct sk_buff *skb, struct genl_info *info) { struct vdpa_mgmt_dev *mdev; const char *name; int err = 0; if (!info->attrs[VDPA_ATTR_DEV_NAME]) return -EINVAL; name = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]); mutex_lock(&vdpa_dev_mutex); mdev = vdpa_mgmtdev_get_from_attr(info->attrs); if (IS_ERR(mdev)) { NL_SET_ERR_MSG_MOD(info->extack, "Fail to find the specified management device"); err = PTR_ERR(mdev); goto err; } err = mdev->ops->dev_add(mdev, name); err: mutex_unlock(&vdpa_dev_mutex); return err; } static int vdpa_nl_cmd_dev_del_set_doit(struct sk_buff *skb, struct genl_info *info) { struct vdpa_mgmt_dev *mdev; struct vdpa_device *vdev; struct device *dev; const char *name; int err = 0; if (!info->attrs[VDPA_ATTR_DEV_NAME]) return -EINVAL; name = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]); mutex_lock(&vdpa_dev_mutex); dev = bus_find_device(&vdpa_bus, NULL, name, vdpa_name_match); if (!dev) { NL_SET_ERR_MSG_MOD(info->extack, "device not found"); err = -ENODEV; goto dev_err; } vdev = container_of(dev, struct vdpa_device, dev); if (!vdev->mdev) { NL_SET_ERR_MSG_MOD(info->extack, "Only user created device can be deleted by user"); err = -EINVAL; goto mdev_err; } mdev = vdev->mdev; mdev->ops->dev_del(mdev, vdev); mdev_err: put_device(dev); dev_err: mutex_unlock(&vdpa_dev_mutex); return err; } static int vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq, int flags, struct netlink_ext_ack *extack) { u16 max_vq_size; u32 device_id; u32 vendor_id; void *hdr; int err; hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, VDPA_CMD_DEV_NEW); if (!hdr) return -EMSGSIZE; err = vdpa_nl_mgmtdev_handle_fill(msg, vdev->mdev); if (err) goto msg_err; device_id = vdev->config->get_device_id(vdev); vendor_id = vdev->config->get_vendor_id(vdev); max_vq_size = vdev->config->get_vq_num_max(vdev); err = -EMSGSIZE; if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev))) goto msg_err; if (nla_put_u32(msg, VDPA_ATTR_DEV_ID, device_id)) goto msg_err; if (nla_put_u32(msg, VDPA_ATTR_DEV_VENDOR_ID, vendor_id)) goto msg_err; if (nla_put_u32(msg, VDPA_ATTR_DEV_MAX_VQS, vdev->nvqs)) goto msg_err; if (nla_put_u16(msg, VDPA_ATTR_DEV_MAX_VQ_SIZE, max_vq_size)) goto msg_err; genlmsg_end(msg, hdr); return 0; msg_err: genlmsg_cancel(msg, hdr); return err; } static int vdpa_nl_cmd_dev_get_doit(struct sk_buff *skb, struct genl_info *info) { struct vdpa_device *vdev; struct sk_buff *msg; const char *devname; struct device *dev; int err; if (!info->attrs[VDPA_ATTR_DEV_NAME]) return -EINVAL; devname = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]); msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!msg) return -ENOMEM; mutex_lock(&vdpa_dev_mutex); dev = bus_find_device(&vdpa_bus, NULL, devname, vdpa_name_match); if (!dev) { NL_SET_ERR_MSG_MOD(info->extack, "device not found"); err = -ENODEV; goto err; } vdev = container_of(dev, struct vdpa_device, dev); if (!vdev->mdev) { err = -EINVAL; goto mdev_err; } err = vdpa_dev_fill(vdev, msg, info->snd_portid, info->snd_seq, 0, info->extack); if (!err) err = genlmsg_reply(msg, info); mdev_err: put_device(dev); err: mutex_unlock(&vdpa_dev_mutex); if (err) nlmsg_free(msg); return err; } struct vdpa_dev_dump_info { struct sk_buff *msg; struct netlink_callback *cb; int start_idx; int idx; }; static int vdpa_dev_dump(struct device *dev, void *data) { struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev); struct vdpa_dev_dump_info *info = data; int err; if (!vdev->mdev) return 0; if (info->idx < info->start_idx) { info->idx++; return 0; } err = vdpa_dev_fill(vdev, info->msg, NETLINK_CB(info->cb->skb).portid, info->cb->nlh->nlmsg_seq, NLM_F_MULTI, info->cb->extack); if (err) return err; info->idx++; return 0; } static int vdpa_nl_cmd_dev_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb) { struct vdpa_dev_dump_info info; info.msg = msg; info.cb = cb; info.start_idx = cb->args[0]; info.idx = 0; mutex_lock(&vdpa_dev_mutex); bus_for_each_dev(&vdpa_bus, NULL, &info, vdpa_dev_dump); mutex_unlock(&vdpa_dev_mutex); cb->args[0] = info.idx; return msg->len; } static const struct nla_policy vdpa_nl_policy[VDPA_ATTR_MAX + 1] = { [VDPA_ATTR_MGMTDEV_BUS_NAME] = { .type = NLA_NUL_STRING }, [VDPA_ATTR_MGMTDEV_DEV_NAME] = { .type = NLA_STRING }, [VDPA_ATTR_DEV_NAME] = { .type = NLA_STRING }, }; static const struct genl_ops vdpa_nl_ops[] = { { .cmd = VDPA_CMD_MGMTDEV_GET, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = vdpa_nl_cmd_mgmtdev_get_doit, .dumpit = vdpa_nl_cmd_mgmtdev_get_dumpit, }, { .cmd = VDPA_CMD_DEV_NEW, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = vdpa_nl_cmd_dev_add_set_doit, .flags = GENL_ADMIN_PERM, }, { .cmd = VDPA_CMD_DEV_DEL, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = vdpa_nl_cmd_dev_del_set_doit, .flags = GENL_ADMIN_PERM, }, { .cmd = VDPA_CMD_DEV_GET, .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = vdpa_nl_cmd_dev_get_doit, .dumpit = vdpa_nl_cmd_dev_get_dumpit, }, }; static struct genl_family vdpa_nl_family __ro_after_init = { .name = VDPA_GENL_NAME, .version = VDPA_GENL_VERSION, .maxattr = VDPA_ATTR_MAX, .policy = vdpa_nl_policy, .netnsok = false, .module = THIS_MODULE, .ops = vdpa_nl_ops, .n_ops = ARRAY_SIZE(vdpa_nl_ops), }; static int vdpa_init(void) { int err; err = bus_register(&vdpa_bus); if (err) return err; err = genl_register_family(&vdpa_nl_family); if (err) goto err; return 0; err: bus_unregister(&vdpa_bus); return err; } static void __exit vdpa_exit(void) { genl_unregister_family(&vdpa_nl_family); bus_unregister(&vdpa_bus); ida_destroy(&vdpa_index_ida); } core_initcall(vdpa_init); module_exit(vdpa_exit); MODULE_AUTHOR("Jason Wang "); MODULE_LICENSE("GPL v2");