[V2,3/5] vDPA: introduce vDPA bus

Message ID	20200210035608.10002-4-jasowang@redhat.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <SRS0=Y5yW=36=vger.kernel.org=kvm-owner@kernel.org> From: Jason Wang <jasowang@redhat.com> To: mst@redhat.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Cc: tiwei.bie@intel.com, jgg@mellanox.com, maxime.coquelin@redhat.com, cunming.liang@intel.com, zhihong.wang@intel.com, rob.miller@broadcom.com, xiao.w.wang@intel.com, haotian.wang@sifive.com, lingshan.zhu@intel.com, eperezma@redhat.com, lulu@redhat.com, parav@mellanox.com, kevin.tian@intel.com, stefanha@redhat.com, rdunlap@infradead.org, hch@infradead.org, aadam@redhat.com, jiri@mellanox.com, shahafs@mellanox.com, hanand@xilinx.com, mhabets@solarflare.com, Jason Wang <jasowang@redhat.com> Subject: [PATCH V2 3/5] vDPA: introduce vDPA bus Date: Mon, 10 Feb 2020 11:56:06 +0800 Message-Id: <20200210035608.10002-4-jasowang@redhat.com> In-Reply-To: <20200210035608.10002-1-jasowang@redhat.com> References: <20200210035608.10002-1-jasowang@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: kvm-owner@vger.kernel.org Precedence: bulk
Series	vDPA support \| expand [V2,0/5] vDPA support [V2,1/5] vhost: factor out IOTLB [V2,2/5] vringh: IOTLB support [V2,3/5] vDPA: introduce vDPA bus [V2,4/5] virtio: introduce a vDPA based transport [V2,5/5] vdpasim: vDPA device simulator

diff --git a/MAINTAINERS b/MAINTAINERS index d4bda9c900fa..578d2a581e3b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17540,6 +17540,7 @@ F: tools/virtio/ F: drivers/net/virtio_net.c F: drivers/block/virtio_blk.c F: include/linux/virtio*.h +F: include/linux/vdpa.h F: include/uapi/linux/virtio_*.h F: drivers/crypto/virtio/ F: mm/balloon_compaction.c diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 078615cf2afc..9c4fdb64d9ac 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -96,3 +96,5 @@ config VIRTIO_MMIO_CMDLINE_DEVICES If unsure, say 'N'. endif # VIRTIO_MENU + +source "drivers/virtio/vdpa/Kconfig" diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 3a2b5c5dcf46..fdf5eacd0d0a 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -6,3 +6,4 @@ virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o +obj-$(CONFIG_VDPA) += vdpa/ diff --git a/drivers/virtio/vdpa/Kconfig b/drivers/virtio/vdpa/Kconfig new file mode 100644 index 000000000000..7a99170e6c30 --- /dev/null +++ b/drivers/virtio/vdpa/Kconfig @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-2.0-only +config VDPA + tristate + default m + help + Enable this module to support vDPA device that uses a + datapath which complies with virtio specifications with + vendor specific control path. + diff --git a/drivers/virtio/vdpa/Makefile b/drivers/virtio/vdpa/Makefile new file mode 100644 index 000000000000..ee6a35e8a4fb --- /dev/null +++ b/drivers/virtio/vdpa/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_VDPA) += vdpa.o diff --git a/drivers/virtio/vdpa/vdpa.c b/drivers/virtio/vdpa/vdpa.c new file mode 100644 index 000000000000..4003d90f5df3 --- /dev/null +++ b/drivers/virtio/vdpa/vdpa.c @@ -0,0 +1,160 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * vDPA bus. + * + * Copyright (c) 2020, Red Hat. All rights reserved. + * Author: Jason Wang <jasowang@redhat.com> + * + */ + +#include <linux/module.h> +#include <linux/idr.h> +#include <linux/vdpa.h> + +static DEFINE_IDA(vdpa_index_ida); + +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 int 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); + + return 0; +} + +static struct bus_type vdpa_bus = { + .name = "vdpa", + .probe = vdpa_dev_probe, + .remove = vdpa_dev_remove, +}; + +/** + * vdpa_init_device - initilaize a vDPA device + * This allows driver to some prepartion between after device is + * initialized but before vdpa_register_device() + * @vdev: the vdpa device to be initialized + * @parent: the paretn device + * @dma_dev: the actual device that is performing DMA + * @config: the bus operations support by this device + * + * Returns an error when parent/config/dma_dev is not set or fail to get + * ida. + */ +int vdpa_init_device(struct vdpa_device *vdev, struct device *parent, + struct device *dma_dev, + const struct vdpa_config_ops *config) +{ + int err; + + if (!parent || !dma_dev || !config) + return -EINVAL; + + err = ida_simple_get(&vdpa_index_ida, 0, 0, GFP_KERNEL); + if (err < 0) + return -EFAULT; + + vdev->dev.bus = &vdpa_bus; + vdev->dev.parent = parent; + + device_initialize(&vdev->dev); + + vdev->index = err; + vdev->dma_dev = dma_dev; + vdev->config = config; + + dev_set_name(&vdev->dev, "vdpa%u", vdev->index); + + return 0; +} +EXPORT_SYMBOL_GPL(vdpa_init_device); + +/** + * vdpa_register_device - register a vDPA device + * Callers must have a succeed call of vdpa_init_device() before. + * @vdev: the vdpa device to be registered to vDPA bus + * + * Returns an error when fail to add to vDPA bus + */ +int vdpa_register_device(struct vdpa_device *vdev) +{ + int err = device_add(&vdev->dev); + + if (err) { + put_device(&vdev->dev); + ida_simple_remove(&vdpa_index_ida, vdev->index); + } + + return err; +} +EXPORT_SYMBOL_GPL(vdpa_register_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) +{ + int index = vdev->index; + + device_unregister(&vdev->dev); + ida_simple_remove(&vdpa_index_ida, index); +} +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 + * + * 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); + +static int vdpa_init(void) +{ + if (bus_register(&vdpa_bus) != 0) + panic("virtio bus registration failed"); + return 0; +} + +static void __exit vdpa_exit(void) +{ + bus_unregister(&vdpa_bus); + ida_destroy(&vdpa_index_ida); +} +core_initcall(vdpa_init); +module_exit(vdpa_exit); + +MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h new file mode 100644 index 000000000000..52543a862801 --- /dev/null +++ b/include/linux/vdpa.h @@ -0,0 +1,233 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_VDPA_H +#define _LINUX_VDPA_H + +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/vhost_iotlb.h> + +/** + * vDPA callback definition. + * @callback: interrupt callback function + * @private: the data passed to the callback function + */ +struct vdpa_callback { + irqreturn_t (*callback)(void *data); + void *private; +}; + +/** + * vDPA device - representation of a vDPA device + * @dev: underlying device + * @dma_dev: the actual device that is performing DMA + * @config: the configuration ops for this device. + * @index: device index + */ +struct vdpa_device { + struct device dev; + struct device *dma_dev; + const struct vdpa_config_ops *config; + int index; +}; + +/** + * vDPA_config_ops - operations for configuring a vDPA device. + * Note: vDPA device drivers are required to implement all of the + * operations unless it is mentioned to be optional in the following + * list. + * + * @set_vq_address: Set the address of virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * @desc_area: address of desc area + * @driver_area: address of driver area + * @device_area: address of device area + * Returns integer: success (0) or error (< 0) + * @set_vq_num: Set the size of virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * @num: the size of virtqueue + * @kick_vq: Kick the virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * @set_vq_cb: Set the interrupt callback function for + * a virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * @cb: virtio-vdev interrupt callback structure + * @set_vq_ready: Set ready status for a virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * @ready: ready (true) not ready(false) + * @get_vq_ready: Get ready status for a virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * Returns boolean: ready (true) or not (false) + * @set_vq_state: Set the state for a virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * @state: virtqueue state (last_avail_idx) + * Returns integer: success (0) or error (< 0) + * @get_vq_state: Get the state for a virtqueue + * @vdev: vdpa device + * @idx: virtqueue index + * Returns virtqueue state (last_avail_idx) + * @get_vq_align: Get the virtqueue align requirement + * for the device + * @vdev: vdpa device + * Returns virtqueue algin requirement + * @get_features: Get virtio features supported by the device + * @vdev: vdpa device + * Returns the virtio features support by the + * device + * @set_features: Set virtio features supported by the driver + * @vdev: vdpa device + * @features: feature support by the driver + * Returns integer: success (0) or error (< 0) + * @set_config_cb: Set the config interrupt callback + * @vdev: vdpa device + * @cb: virtio-vdev interrupt callback structure + * @get_vq_num_max: Get the max size of virtqueue + * @vdev: vdpa device + * Returns u16: max size of virtqueue + * @get_device_id: Get virtio device id + * @vdev: vdpa device + * Returns u32: virtio device id + * @get_vendor_id: Get id for the vendor that provides this device + * @vdev: vdpa device + * Returns u32: virtio vendor id + * @get_status: Get the device status + * @vdev: vdpa device + * Returns u8: virtio device status + * @set_status: Set the device status + * @vdev: vdpa device + * @status: virtio device status + * @get_config: Read from device specific configuration space + * @vdev: vdpa device + * @offset: offset from the beginning of + * configuration space + * @buf: buffer used to read to + * @len: the length to read from + * configuration space + * @set_config: Write to device specific configuration space + * @vdev: vdpa device + * @offset: offset from the beginning of + * configuration space + * @buf: buffer used to write from + * @len: the length to write to + * configuration space + * @get_generation: Get device config generation (optional) + * @vdev: vdpa device + * Returns u32: device generation + * @set_map: Set device memory mapping (optional) + * and only needed for device that using + * device specific DMA translation + * (on-chip IOMMU) + * @vdev: vdpa device + * @iotlb: vhost memory mapping to be + * used by the vDPA + * Returns integer: success (0) or error (< 0) + * @dma_map: Map an area of PA to IOVA + * @vdev: vdpa device + * @iova: iova to be mapped + * @size: size of the area + * @pa: physical address for the map + * @perm: device access permission (VHOST_MAP_XX) + * Returns integer: success (0) or error (< 0) + * @dma_unmap: Unmap an area of IOVA + * @vdev: vdpa device + * @iova: iova to be unmapped + * @size: size of the area + * Returns integer: success (0) or error (< 0) + */ +struct vdpa_config_ops { + /* Virtqueue ops */ + int (*set_vq_address)(struct vdpa_device *vdev, + u16 idx, u64 desc_area, u64 driver_area, + u64 device_area); + void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num); + void (*kick_vq)(struct vdpa_device *vdev, u16 idx); + void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx, + struct vdpa_callback *cb); + void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready); + bool (*get_vq_ready)(struct vdpa_device *vdev, u16 idx); + int (*set_vq_state)(struct vdpa_device *vdev, u16 idx, u64 state); + u64 (*get_vq_state)(struct vdpa_device *vdev, u16 idx); + + /* Device ops */ + u16 (*get_vq_align)(struct vdpa_device *vdev); + u64 (*get_features)(struct vdpa_device *vdev); + int (*set_features)(struct vdpa_device *vdev, u64 features); + void (*set_config_cb)(struct vdpa_device *vdev, + struct vdpa_callback *cb); + u16 (*get_vq_num_max)(struct vdpa_device *vdev); + u32 (*get_device_id)(struct vdpa_device *vdev); + u32 (*get_vendor_id)(struct vdpa_device *vdev); + u8 (*get_status)(struct vdpa_device *vdev); + void (*set_status)(struct vdpa_device *vdev, u8 status); + void (*get_config)(struct vdpa_device *vdev, unsigned int offset, + void *buf, unsigned int len); + void (*set_config)(struct vdpa_device *vdev, unsigned int offset, + const void *buf, unsigned int len); + u32 (*get_generation)(struct vdpa_device *vdev); + + /* DMA ops */ + int (*set_map)(struct vdpa_device *vdev, struct vhost_iotlb *iotlb); + int (*dma_map)(struct vdpa_device *vdev, u64 iova, u64 size, + u64 pa, u32 perm); + int (*dma_unmap)(struct vdpa_device *vdev, u64 iova, u64 size); +}; + +int vdpa_init_device(struct vdpa_device *vdev, + struct device *parent, + struct device *dma_dev, + const struct vdpa_config_ops *config); +int vdpa_register_device(struct vdpa_device *vdev); +void vdpa_unregister_device(struct vdpa_device *vdev); + +/** + * vdpa_driver - operations for a vDPA driver + * @driver: underlying device driver + * @probe: the function to call when a device is found. Returns 0 or -errno. + * @remove: the function to call when a device is removed. + */ +struct vdpa_driver { + struct device_driver driver; + int (*probe)(struct vdpa_device *vdev); + void (*remove)(struct vdpa_device *vdev); +}; + +#define vdpa_register_driver(drv) \ + __vdpa_register_driver(drv, THIS_MODULE) +int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner); +void vdpa_unregister_driver(struct vdpa_driver *drv); + +#define module_vdpa_driver(__vdpa_driver) \ + module_driver(__vdpa_driver, vdpa_register_driver, \ + vdpa_unregister_driver) + +static inline struct vdpa_driver *drv_to_vdpa(struct device_driver *driver) +{ + return container_of(driver, struct vdpa_driver, driver); +} + +static inline struct vdpa_device *dev_to_vdpa(struct device *_dev) +{ + return container_of(_dev, struct vdpa_device, dev); +} + +static inline void *vdpa_get_drvdata(const struct vdpa_device *vdev) +{ + return dev_get_drvdata(&vdev->dev); +} + +static inline void vdpa_set_drvdata(struct vdpa_device *vdev, void *data) +{ + dev_set_drvdata(&vdev->dev, data); +} + +static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev) +{ + return vdev->dma_dev; +} +#endif /* _LINUX_VDPA_H */

[V2,3/5] vDPA: introduce vDPA bus

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