Add a new endpoint function driver to register VHOST device and provide interface for the VHOST driver to access virtqueues created by the remote host (using VIRTIO).
Signed-off-by: Kishon Vijay Abraham I <kis...@ti.com> --- drivers/pci/endpoint/functions/Kconfig | 11 + drivers/pci/endpoint/functions/Makefile | 1 + .../pci/endpoint/functions/pci-epf-vhost.c | 1144 +++++++++++++++++ drivers/vhost/vhost_cfs.c | 13 - include/linux/vhost.h | 14 + 5 files changed, 1170 insertions(+), 13 deletions(-) create mode 100644 drivers/pci/endpoint/functions/pci-epf-vhost.c diff --git a/drivers/pci/endpoint/functions/Kconfig b/drivers/pci/endpoint/functions/Kconfig index 55ac7bb2d469..21830576e1f4 100644 --- a/drivers/pci/endpoint/functions/Kconfig +++ b/drivers/pci/endpoint/functions/Kconfig @@ -24,3 +24,14 @@ config PCI_EPF_NTB device tree. If in doubt, say "N" to disable Endpoint NTB driver. + +config PCI_EPF_VHOST + tristate "PCI Endpoint VHOST driver" + depends on PCI_ENDPOINT + help + Select this configuration option to enable the VHOST driver + for PCI Endpoint. EPF VHOST driver implements VIRTIO backend + for EPF and uses the VHOST framework to bind any VHOST driver + to the VHOST device created by this driver. + + If in doubt, say "N" to disable Endpoint VHOST driver. diff --git a/drivers/pci/endpoint/functions/Makefile b/drivers/pci/endpoint/functions/Makefile index 96ab932a537a..39d4f9daf63a 100644 --- a/drivers/pci/endpoint/functions/Makefile +++ b/drivers/pci/endpoint/functions/Makefile @@ -5,3 +5,4 @@ obj-$(CONFIG_PCI_EPF_TEST) += pci-epf-test.o obj-$(CONFIG_PCI_EPF_NTB) += pci-epf-ntb.o +obj-$(CONFIG_PCI_EPF_VHOST) += pci-epf-vhost.o diff --git a/drivers/pci/endpoint/functions/pci-epf-vhost.c b/drivers/pci/endpoint/functions/pci-epf-vhost.c new file mode 100644 index 000000000000..d090e5e88575 --- /dev/null +++ b/drivers/pci/endpoint/functions/pci-epf-vhost.c @@ -0,0 +1,1144 @@ +// SPDX-License-Identifier: GPL-2.0 +/** + * Endpoint Function Driver to implement VHOST functionality + * + * Copyright (C) 2020 Texas Instruments + * Author: Kishon Vijay Abraham I <kis...@ti.com> + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/vhost.h> +#include <linux/vringh.h> + +#include <linux/pci-epc.h> +#include <linux/pci-epf.h> + +#include <uapi/linux/virtio_pci.h> + +#define MAX_VQS 8 + +#define VHOST_QUEUE_STATUS_ENABLE BIT(0) + +#define VHOST_DEVICE_CONFIG_SIZE 1024 +#define EPF_VHOST_MAX_INTERRUPTS (MAX_VQS + 1) + +static struct workqueue_struct *kpcivhost_workqueue; + +struct epf_vhost_queue { + struct delayed_work cmd_handler; + struct vhost_virtqueue *vq; + struct epf_vhost *vhost; + phys_addr_t phys_addr; + void __iomem *addr; + unsigned int size; +}; + +struct epf_vhost { + const struct pci_epc_features *epc_features; + struct epf_vhost_queue vqueue[MAX_VQS]; + struct delayed_work cmd_handler; + struct delayed_work cfs_work; + struct epf_vhost_reg *reg; + struct config_group group; + size_t msix_table_offset; + struct vhost_dev vdev; + struct pci_epf *epf; + struct vring vring; + int msix_bar; +}; + +static inline struct epf_vhost *to_epf_vhost_from_ci(struct config_item *item) +{ + return container_of(to_config_group(item), struct epf_vhost, group); +} + +#define to_epf_vhost(v) container_of((v), struct epf_vhost, vdev) + +struct epf_vhost_reg_queue { + u8 cmd; + u8 cmd_status; + u16 status; + u16 num_buffers; + u16 msix_vector; + u64 queue_addr; +} __packed; + +enum queue_cmd { + QUEUE_CMD_NONE, + QUEUE_CMD_ACTIVATE, + QUEUE_CMD_DEACTIVATE, + QUEUE_CMD_NOTIFY, +}; + +enum queue_cmd_status { + QUEUE_CMD_STATUS_NONE, + QUEUE_CMD_STATUS_OKAY, + QUEUE_CMD_STATUS_ERROR, +}; + +struct epf_vhost_reg { + u64 host_features; + u64 guest_features; + u16 msix_config; + u16 num_queues; + u8 device_status; + u8 config_generation; + u32 isr; + u8 cmd; + u8 cmd_status; + struct epf_vhost_reg_queue vq[MAX_VQS]; +} __packed; + +enum host_cmd { + HOST_CMD_NONE, + HOST_CMD_SET_STATUS, + HOST_CMD_FINALIZE_FEATURES, + HOST_CMD_RESET, +}; + +enum host_cmd_status { + HOST_CMD_STATUS_NONE, + HOST_CMD_STATUS_OKAY, + HOST_CMD_STATUS_ERROR, +}; + +static struct pci_epf_header epf_vhost_header = { + .vendorid = PCI_ANY_ID, + .deviceid = PCI_ANY_ID, + .baseclass_code = PCI_CLASS_OTHERS, + .interrupt_pin = PCI_INTERRUPT_INTA, +}; + +/* pci_epf_vhost_cmd_handler - Handle commands from remote EPF virtio driver + * @work: The work_struct holding the pci_epf_vhost_cmd_handler() function that + * is scheduled + * + * Handle commands from the remote EPF virtio driver and sends notification to + * the vhost client driver. The remote EPF virtio driver sends commands when the + * virtio driver status is updated or when the feature negotiation is complete or + * if the virtio driver wants to reset the device. + */ +static void pci_epf_vhost_cmd_handler(struct work_struct *work) +{ + struct epf_vhost_reg *reg; + struct epf_vhost *vhost; + struct vhost_dev *vdev; + struct device *dev; + u8 command; + + vhost = container_of(work, struct epf_vhost, cmd_handler.work); + vdev = &vhost->vdev; + dev = &vhost->epf->dev; + reg = vhost->reg; + + command = reg->cmd; + if (!command) + goto reset_handler; + + reg->cmd = 0; + + switch (command) { + case HOST_CMD_SET_STATUS: + blocking_notifier_call_chain(&vdev->notifier, NOTIFY_SET_STATUS, + NULL); + reg->cmd_status = HOST_CMD_STATUS_OKAY; + break; + case HOST_CMD_FINALIZE_FEATURES: + vdev->features = reg->guest_features; + blocking_notifier_call_chain(&vdev->notifier, + NOTIFY_FINALIZE_FEATURES, 0); + reg->cmd_status = HOST_CMD_STATUS_OKAY; + break; + case HOST_CMD_RESET: + blocking_notifier_call_chain(&vdev->notifier, NOTIFY_RESET, 0); + reg->cmd_status = HOST_CMD_STATUS_OKAY; + break; + default: + dev_err(dev, "UNKNOWN command: %d\n", command); + break; + } + +reset_handler: + queue_delayed_work(kpcivhost_workqueue, &vhost->cmd_handler, + msecs_to_jiffies(1)); +} + +/* pci_epf_vhost_queue_activate - Map virtqueue local address to remote + * virtqueue address provided by EPF virtio + * @vqueue: struct epf_vhost_queue holding the local virtqueue address + * + * In order for the local system to access the remote virtqueue, the address + * reserved in local system should be mapped to the remote virtqueue address. + * Map local virtqueue address to remote virtqueue address here. + */ +static int pci_epf_vhost_queue_activate(struct epf_vhost_queue *vqueue) +{ + struct epf_vhost_reg_queue *reg_queue; + struct vhost_virtqueue *vq; + struct epf_vhost_reg *reg; + phys_addr_t vq_phys_addr; + struct epf_vhost *vhost; + struct pci_epf *epf; + struct pci_epc *epc; + struct device *dev; + u64 vq_remote_addr; + size_t vq_size; + u8 func_no; + int ret; + + vhost = vqueue->vhost; + epf = vhost->epf; + dev = &epf->dev; + epc = epf->epc; + func_no = epf->func_no; + + vq = vqueue->vq; + reg = vhost->reg; + reg_queue = ®->vq[vq->index]; + vq_phys_addr = vqueue->phys_addr; + vq_remote_addr = reg_queue->queue_addr; + vq_size = vqueue->size; + + ret = pci_epc_map_addr(epc, func_no, vq_phys_addr, vq_remote_addr, + vq_size); + if (ret) { + dev_err(dev, "Failed to map outbound address\n"); + return ret; + } + + reg_queue->status |= VHOST_QUEUE_STATUS_ENABLE; + + return 0; +} + +/* pci_epf_vhost_queue_deactivate - Unmap virtqueue local address from remote + * virtqueue address + * @vqueue: struct epf_vhost_queue holding the local virtqueue address + * + * Unmap virtqueue local address from remote virtqueue address. + */ +static void pci_epf_vhost_queue_deactivate(struct epf_vhost_queue *vqueue) +{ + struct epf_vhost_reg_queue *reg_queue; + struct vhost_virtqueue *vq; + struct epf_vhost_reg *reg; + phys_addr_t vq_phys_addr; + struct epf_vhost *vhost; + struct pci_epf *epf; + struct pci_epc *epc; + u8 func_no; + + vhost = vqueue->vhost; + + epf = vhost->epf; + epc = epf->epc; + func_no = epf->func_no; + vq_phys_addr = vqueue->phys_addr; + + pci_epc_unmap_addr(epc, func_no, vq_phys_addr); + + reg = vhost->reg; + vq = vqueue->vq; + reg_queue = ®->vq[vq->index]; + reg_queue->status &= ~VHOST_QUEUE_STATUS_ENABLE; +} + +/* pci_epf_vhost_queue_cmd_handler - Handle commands from remote EPF virtio + * driver sent for a particular virtqueue + * @work: The work_struct holding the pci_epf_vhost_queue_cmd_handler() + * function that is scheduled + * + * Handle commands from the remote EPF virtio driver sent for a particular + * virtqueue to activate/de-activate a virtqueue or to send notification to + * the vhost client driver. + */ +static void pci_epf_vhost_queue_cmd_handler(struct work_struct *work) +{ + struct epf_vhost_reg_queue *reg_queue; + struct epf_vhost_queue *vqueue; + struct vhost_virtqueue *vq; + struct epf_vhost_reg *reg; + struct epf_vhost *vhost; + struct device *dev; + u8 command; + int ret; + + vqueue = container_of(work, struct epf_vhost_queue, cmd_handler.work); + vhost = vqueue->vhost; + reg = vhost->reg; + vq = vqueue->vq; + reg_queue = ®->vq[vq->index]; + dev = &vhost->epf->dev; + + command = reg_queue->cmd; + if (!command) + goto reset_handler; + + reg_queue->cmd = 0; + vq = vqueue->vq; + + switch (command) { + case QUEUE_CMD_ACTIVATE: + ret = pci_epf_vhost_queue_activate(vqueue); + if (ret) + reg_queue->cmd_status = QUEUE_CMD_STATUS_ERROR; + else + reg_queue->cmd_status = QUEUE_CMD_STATUS_OKAY; + break; + case QUEUE_CMD_DEACTIVATE: + pci_epf_vhost_queue_deactivate(vqueue); + reg_queue->cmd_status = QUEUE_CMD_STATUS_OKAY; + break; + case QUEUE_CMD_NOTIFY: + vhost_virtqueue_callback(vqueue->vq); + reg_queue->cmd_status = QUEUE_CMD_STATUS_OKAY; + break; + default: + dev_err(dev, "UNKNOWN QUEUE command: %d\n", command); + break; +} + +reset_handler: + queue_delayed_work(kpcivhost_workqueue, &vqueue->cmd_handler, + msecs_to_jiffies(1)); +} + +/* pci_epf_vhost_write - Write data to buffer provided by remote virtio driver + * @vdev: Vhost device that communicates with remove virtio device + * @dst: Buffer address present in the memory of the remote system to which + * data should be written + * @src: Buffer address in the local device provided by the vhost client driver + * @len: Length of the data to be copied from @src to @dst + * + * Write data to buffer provided by remote virtio driver from buffer provided + * by vhost client driver. + */ +static int pci_epf_vhost_write(struct vhost_dev *vdev, u64 dst, void *src, int len) +{ + const struct pci_epc_features *epc_features; + struct epf_vhost *vhost; + phys_addr_t phys_addr; + struct pci_epf *epf; + struct pci_epc *epc; + void __iomem *addr; + struct device *dev; + int offset, ret; + u64 dst_addr; + size_t align; + u8 func_no; + + vhost = to_epf_vhost(vdev); + epf = vhost->epf; + dev = &epf->dev; + epc = epf->epc; + func_no = epf->func_no; + epc_features = vhost->epc_features; + align = epc_features->align; + + offset = dst & (align - 1); + dst_addr = dst & ~(align - 1); + + addr = pci_epc_mem_alloc_addr(epc, &phys_addr, len); + if (!addr) { + dev_err(dev, "Failed to allocate outbound address\n"); + return -ENOMEM; + } + + ret = pci_epc_map_addr(epc, func_no, phys_addr, dst_addr, len); + if (ret) { + dev_err(dev, "Failed to map outbound address\n"); + goto ret; + } + + memcpy_toio(addr + offset, src, len); + + pci_epc_unmap_addr(epc, func_no, phys_addr); + +ret: + pci_epc_mem_free_addr(epc, phys_addr, addr, len); + + return ret; +} + +/* ntb_vhost_read - Read data from buffer provided by remote virtio driver + * @vdev: Vhost device that communicates with remove virtio device + * @dst: Buffer address in the local device provided by the vhost client driver + * @src: Buffer address in the remote device provided by the remote virtio + * driver + * @len: Length of the data to be copied from @src to @dst + * + * Read data from buffer provided by remote virtio driver to address provided + * by vhost client driver. + */ +static int pci_epf_vhost_read(struct vhost_dev *vdev, void *dst, u64 src, int len) +{ + const struct pci_epc_features *epc_features; + struct epf_vhost *vhost; + phys_addr_t phys_addr; + struct pci_epf *epf; + struct pci_epc *epc; + void __iomem *addr; + struct device *dev; + int offset, ret; + u64 src_addr; + size_t align; + u8 func_no; + + vhost = to_epf_vhost(vdev); + epf = vhost->epf; + dev = &epf->dev; + epc = epf->epc; + func_no = epf->func_no; + epc_features = vhost->epc_features; + align = epc_features->align; + + offset = src & (align - 1); + src_addr = src & ~(align - 1); + + addr = pci_epc_mem_alloc_addr(epc, &phys_addr, len); + if (!addr) { + dev_err(dev, "Failed to allocate outbound address\n"); + return -ENOMEM; + } + + ret = pci_epc_map_addr(epc, func_no, phys_addr, src_addr, len); + if (ret) { + dev_err(dev, "Failed to map outbound address\n"); + goto ret; + } + + memcpy_fromio(dst, addr + offset, len); + + pci_epc_unmap_addr(epc, func_no, phys_addr); + +ret: + pci_epc_mem_free_addr(epc, phys_addr, addr, len); + + return ret; +} + +/* pci_epf_vhost_notify - Send notification to the remote virtqueue + * @vq: The local vhost virtqueue corresponding to the remote virtio virtqueue + * + * Use endpoint core framework to raise MSI-X interrupt to notify the remote + * virtqueue. + */ +static void pci_epf_vhost_notify(struct vhost_virtqueue *vq) +{ + struct epf_vhost_reg_queue *reg_queue; + struct epf_vhost_reg *reg; + struct epf_vhost *vhost; + struct vhost_dev *vdev; + struct pci_epf *epf; + struct pci_epc *epc; + u8 func_no; + + vdev = vq->dev; + vhost = to_epf_vhost(vdev); + epf = vhost->epf; + func_no = epf->func_no; + epc = epf->epc; + reg = vhost->reg; + reg_queue = ®->vq[vq->index]; + + pci_epc_raise_irq(epc, func_no, PCI_EPC_IRQ_MSIX, + reg_queue->msix_vector + 1); +} + +/* pci_epf_vhost_del_vqs - Delete all the vqs associated with the vhost device + * @vdev: Vhost device that communicates with remove virtio device + * + * Delete all the vqs associated with the vhost device and free the memory + * address reserved for accessing the remote virtqueue. + */ +static void pci_epf_vhost_del_vqs(struct vhost_dev *vdev) +{ + struct epf_vhost_queue *vqueue; + struct vhost_virtqueue *vq; + phys_addr_t vq_phys_addr; + struct epf_vhost *vhost; + void __iomem *vq_addr; + unsigned int vq_size; + struct pci_epf *epf; + struct pci_epc *epc; + int i; + + vhost = to_epf_vhost(vdev); + epf = vhost->epf; + epc = epf->epc; + + for (i = 0; i < vdev->nvqs; i++) { + vq = vdev->vqs[i]; + if (IS_ERR_OR_NULL(vq)) + continue; + + vqueue = &vhost->vqueue[i]; + vq_phys_addr = vqueue->phys_addr; + vq_addr = vqueue->addr; + vq_size = vqueue->size; + pci_epc_mem_free_addr(epc, vq_phys_addr, vq_addr, vq_size); + kfree(vq); + } +} + +/* pci_epf_vhost_create_vq - Create a new vhost virtqueue + * @vdev: Vhost device that communicates with remove virtio device + * @index: Index of the vhost virtqueue + * @num_bufs: The number of buffers that should be supported by the vhost + * virtqueue (number of descriptors in the vhost virtqueue) + * @callback: Callback function associated with the virtqueue + * + * Create a new vhost virtqueue which can be used by the vhost client driver + * to access the remote virtio. This sets up the local address of the vhost + * virtqueue but shouldn't be accessed until the virtio sets the status to + * VIRTIO_CONFIG_S_DRIVER_OK. + */ +static struct vhost_virtqueue * +pci_epf_vhost_create_vq(struct vhost_dev *vdev, int index, + unsigned int num_bufs, + void (*callback)(struct vhost_virtqueue *)) +{ + struct epf_vhost_reg_queue *reg_queue; + struct epf_vhost_queue *vqueue; + struct epf_vhost_reg *reg; + struct vhost_virtqueue *vq; + phys_addr_t vq_phys_addr; + struct epf_vhost *vhost; + struct vringh *vringh; + void __iomem *vq_addr; + unsigned int vq_size; + struct vring *vring; + struct pci_epf *epf; + struct pci_epc *epc; + struct device *dev; + int ret; + + vhost = to_epf_vhost(vdev); + vqueue = &vhost->vqueue[index]; + reg = vhost->reg; + reg_queue = ®->vq[index]; + epf = vhost->epf; + epc = epf->epc; + dev = &epf->dev; + + vq = kzalloc(sizeof(*vq), GFP_KERNEL); + if (!vq) + return ERR_PTR(-ENOMEM); + + vq->dev = vdev; + vq->callback = callback; + vq->num = num_bufs; + vq->index = index; + vq->notify = pci_epf_vhost_notify; + vq->type = VHOST_TYPE_MMIO; + + vqueue->vq = vq; + vqueue->vhost = vhost; + + vringh = &vq->vringh; + vring = &vringh->vring; + reg_queue->num_buffers = num_bufs; + + vq_size = vring_size(num_bufs, VIRTIO_PCI_VRING_ALIGN); + vq_addr = pci_epc_mem_alloc_addr(epc, &vq_phys_addr, vq_size); + if (!vq_addr) { + dev_err(dev, "Failed to allocate virtqueue address\n"); + ret = -ENOMEM; + goto err_mem_alloc_addr; + } + + vring_init(vring, num_bufs, vq_addr, VIRTIO_PCI_VRING_ALIGN); + ret = vringh_init_mmio(vringh, 0, num_bufs, false, vring->desc, + vring->avail, vring->used); + if (ret) { + dev_err(dev, "Failed to init vringh\n"); + goto err_init_mmio; + } + + vqueue->phys_addr = vq_phys_addr; + vqueue->addr = vq_addr; + vqueue->size = vq_size; + + INIT_DELAYED_WORK(&vqueue->cmd_handler, pci_epf_vhost_queue_cmd_handler); + queue_work(kpcivhost_workqueue, &vqueue->cmd_handler.work); + + return vq; + +err_init_mmio: + pci_epc_mem_free_addr(epc, vq_phys_addr, vq_addr, vq_size); + +err_mem_alloc_addr: + kfree(vq); + + return ERR_PTR(ret); +} + +/* pci_epf_vhost_create_vqs - Create vhost virtqueues for vhost device + * @vdev: Vhost device that communicates with the remote virtio device + * @nvqs: Number of vhost virtqueues to be created + * @num_bufs: The number of buffers that should be supported by the vhost + * virtqueue (number of descriptors in the vhost virtqueue) + * @vqs: Pointers to all the created vhost virtqueues + * @callback: Callback function associated with the virtqueue + * @names: Names associated with each virtqueue + * + * Create vhost virtqueues for vhost device. This acts as a wrapper to + * pci_epf_vhost_create_vq() which creates individual vhost virtqueue. + */ +static int pci_epf_vhost_create_vqs(struct vhost_dev *vdev, unsigned int nvqs, + unsigned int num_bufs, + struct vhost_virtqueue *vqs[], + vhost_vq_callback_t *callbacks[], + const char * const names[]) +{ + struct epf_vhost *vhost; + struct pci_epf *epf; + struct device *dev; + int ret, i; + + vhost = to_epf_vhost(vdev); + epf = vhost->epf; + dev = &epf->dev; + + for (i = 0; i < nvqs; i++) { + vqs[i] = pci_epf_vhost_create_vq(vdev, i, num_bufs, + callbacks[i]); + if (IS_ERR_OR_NULL(vqs[i])) { + ret = PTR_ERR(vqs[i]); + dev_err(dev, "Failed to create virtqueue\n"); + goto err; + } + } + + vdev->nvqs = nvqs; + vdev->vqs = vqs; + + return 0; + +err: + pci_epf_vhost_del_vqs(vdev); + return ret; +} + +/* pci_epf_vhost_set_features - vhost_config_ops to set vhost device features + * @vdev: Vhost device that communicates with the remote virtio device + * @features: Features supported by the vhost client driver + * + * vhost_config_ops invoked by the vhost client driver to set vhost device + * features. + */ +static int pci_epf_vhost_set_features(struct vhost_dev *vdev, u64 features) +{ + struct epf_vhost_reg *reg; + struct epf_vhost *vhost; + + vhost = to_epf_vhost(vdev); + reg = vhost->reg; + + reg->host_features = features; + + return 0; +} + +/* ntb_vhost_set_status - vhost_config_ops to set vhost device status + * @vdev: Vhost device that communicates with the remote virtio device + * @status: Vhost device status configured by vhost client driver + * + * vhost_config_ops invoked by the vhost client driver to set vhost device + * status. + */ +static int pci_epf_vhost_set_status(struct vhost_dev *vdev, u8 status) +{ + struct epf_vhost_reg *reg; + struct epf_vhost *vhost; + + vhost = to_epf_vhost(vdev); + reg = vhost->reg; + + reg->device_status = status; + + return 0; +} + +/* ntb_vhost_get_status - vhost_config_ops to get vhost device status + * @vdev: Vhost device that communicates with the remote virtio device + * + * vhost_config_ops invoked by the vhost client driver to get vhost device + * status set by the remote virtio driver. + */ +static u8 pci_epf_vhost_get_status(struct vhost_dev *vdev) +{ + struct epf_vhost_reg *reg; + struct epf_vhost *vhost; + + vhost = to_epf_vhost(vdev); + reg = vhost->reg; + + return reg->device_status; +} + +static const struct vhost_config_ops pci_epf_vhost_ops = { + .create_vqs = pci_epf_vhost_create_vqs, + .del_vqs = pci_epf_vhost_del_vqs, + .write = pci_epf_vhost_write, + .read = pci_epf_vhost_read, + .set_features = pci_epf_vhost_set_features, + .set_status = pci_epf_vhost_set_status, + .get_status = pci_epf_vhost_get_status, +}; + +/* pci_epf_vhost_write_header - Write to PCIe standard configuration space + * header + * @vhost: EPF vhost containing the vhost device that communicates with the + * remote virtio device + * + * Invokes endpoint core framework's pci_epc_write_header() to write to the + * standard configuration space header. + */ +static int pci_epf_vhost_write_header(struct epf_vhost *vhost) +{ + struct pci_epf_header *header; + struct vhost_dev *vdev; + struct pci_epc *epc; + struct pci_epf *epf; + struct device *dev; + u8 func_no; + int ret; + + vdev = &vhost->vdev; + epf = vhost->epf; + dev = &epf->dev; + epc = epf->epc; + func_no = epf->func_no; + header = epf->header; + + ret = pci_epc_write_header(epc, func_no, header); + if (ret) { + dev_err(dev, "Configuration header write failed\n"); + return ret; + } + + return 0; +} + +/* pci_epf_vhost_release_dev - Callback function to free device + * @dev: Device in vhost_dev that has to be freed + * + * Callback function from device core invoked to free the device after + * all references have been removed. This frees the allocated memory for + * struct ntb_vhost. + */ +static void pci_epf_vhost_release_dev(struct device *dev) +{ + struct epf_vhost *vhost; + struct vhost_dev *vdev; + + vdev = to_vhost_dev(dev); + vhost = to_epf_vhost(vdev); + + kfree(vhost); +} + +/* pci_epf_vhost_register - Register a vhost device + * @vhost: EPF vhost containing the vhost device that communicates with the + * remote virtio device + * + * Invoked vhost_register_device() to register a vhost device after populating + * the deviceID and vendorID of the vhost device. + */ +static int pci_epf_vhost_register(struct epf_vhost *vhost) +{ + struct vhost_dev *vdev; + struct pci_epf *epf; + struct device *dev; + int ret; + + vdev = &vhost->vdev; + epf = vhost->epf; + dev = &epf->dev; + + vdev->dev.parent = dev; + vdev->dev.release = pci_epf_vhost_release_dev; + vdev->id.device = vhost->epf->header->subsys_id; + vdev->id.vendor = vhost->epf->header->subsys_vendor_id; + vdev->ops = &pci_epf_vhost_ops; + + ret = vhost_register_device(vdev); + if (ret) { + dev_err(dev, "Failed to register vhost device\n"); + return ret; + } + + return 0; +} + +/* pci_epf_vhost_configure_bar - Configure BAR of EPF device + * @vhost: EPF vhost containing the vhost device that communicates with the + * remote virtio device + * + * Allocate memory for the standard virtio configuration space and map it to + * the first free BAR. + */ +static int pci_epf_vhost_configure_bar(struct epf_vhost *vhost) +{ + size_t msix_table_size = 0, pba_size = 0, align, bar_size; + const struct pci_epc_features *epc_features; + struct pci_epf_bar *epf_bar; + struct vhost_dev *vdev; + struct pci_epf *epf; + struct pci_epc *epc; + struct device *dev; + bool msix_capable; + u32 config_size; + int barno, ret; + void *base; + u64 size; + + vdev = &vhost->vdev; + epf = vhost->epf; + dev = &epf->dev; + epc = epf->epc; + + epc_features = vhost->epc_features; + barno = pci_epc_get_first_free_bar(epc_features); + if (barno < 0) { + dev_err(dev, "Failed to get free BAR\n"); + return barno; + } + + size = epc_features->bar_fixed_size[barno]; + align = epc_features->align; + /* Check if epc_features is populated incorrectly */ + if ((!IS_ALIGNED(size, align))) + return -EINVAL; + + config_size = sizeof(struct epf_vhost_reg) + VHOST_DEVICE_CONFIG_SIZE; + config_size = ALIGN(config_size, 8); + + msix_capable = epc_features->msix_capable; + if (msix_capable) { + msix_table_size = PCI_MSIX_ENTRY_SIZE * epf->msix_interrupts; + vhost->msix_table_offset = config_size; + vhost->msix_bar = barno; + /* Align to QWORD or 8 Bytes */ + pba_size = ALIGN(DIV_ROUND_UP(epf->msix_interrupts, 8), 8); + } + + bar_size = config_size + msix_table_size + pba_size; + + if (!align) + bar_size = roundup_pow_of_two(bar_size); + else + bar_size = ALIGN(bar_size, align); + + if (!size) + size = bar_size; + else if (size < bar_size) + return -EINVAL; + + base = pci_epf_alloc_space(epf, size, barno, align, + PRIMARY_INTERFACE); + if (!base) { + dev_err(dev, "Failed to allocate configuration region\n"); + return -ENOMEM; + } + + epf_bar = &epf->bar[barno]; + ret = pci_epc_set_bar(epc, epf->func_no, epf_bar); + if (ret) { + dev_err(dev, "Failed to set BAR: %d\n", barno); + goto err_set_bar; + } + + vhost->reg = base; + + return 0; + +err_set_bar: + pci_epf_free_space(epf, base, barno, PRIMARY_INTERFACE); + + return ret; +} + +/* pci_epf_vhost_configure_interrupts - Configure MSI/MSI-X capability of EPF + * device + * @vhost: EPF vhost containing the vhost device that communicates with the + * remote virtio device + * + * Configure MSI/MSI-X capability of EPF device. This will be used to interrupt + * the vhost virtqueue. + */ +static int pci_epf_vhost_configure_interrupts(struct epf_vhost *vhost) +{ + const struct pci_epc_features *epc_features; + struct pci_epf *epf; + struct pci_epc *epc; + struct device *dev; + int ret; + + epc_features = vhost->epc_features; + epf = vhost->epf; + dev = &epf->dev; + epc = epf->epc; + + if (epc_features->msi_capable) { + ret = pci_epc_set_msi(epc, epf->func_no, + EPF_VHOST_MAX_INTERRUPTS); + if (ret) { + dev_err(dev, "MSI configuration failed\n"); + return ret; + } + } + + if (epc_features->msix_capable) { + ret = pci_epc_set_msix(epc, epf->func_no, + EPF_VHOST_MAX_INTERRUPTS, + vhost->msix_bar, + vhost->msix_table_offset); + if (ret) { + dev_err(dev, "MSI-X configuration failed\n"); + return ret; + } + } + + return 0; +} + +/* pci_epf_vhost_cfs_link - Link vhost client driver with EPF vhost to get + * the deviceID and driverID to be writtent to the PCIe config space + * @epf_vhost_item: Config item representing the EPF vhost created by this + * driver + * @epf: Endpoint function device that is bound to the endpoint controller + * + * This is invoked when the user creates a softlink between the vhost client + * to the EPF vhost. This gets the deviceID and vendorID data from the vhost + * client and copies it to the subys_id and subsys_vendor_id of the EPF + * header. This will be used by the remote virtio to bind a virtio client + * driver. + */ +static int pci_epf_vhost_cfs_link(struct config_item *epf_vhost_item, + struct config_item *driver_item) +{ + struct vhost_driver_item *vdriver_item; + struct epf_vhost *vhost; + + vdriver_item = to_vhost_driver_item(driver_item); + vhost = to_epf_vhost_from_ci(epf_vhost_item); + + vhost->epf->header->subsys_id = vdriver_item->device; + vhost->epf->header->subsys_vendor_id = vdriver_item->vendor; + + return 0; +} + +static struct configfs_item_operations pci_epf_vhost_cfs_ops = { + .allow_link = pci_epf_vhost_cfs_link, +}; + +static const struct config_item_type pci_epf_vhost_cfs_type = { + .ct_item_ops = &pci_epf_vhost_cfs_ops, + .ct_owner = THIS_MODULE, +}; + +/* pci_epf_vhost_cfs_work - Delayed work function to create configfs directory + * to perform EPF vhost specific initializations + * @work: The work_struct holding the pci_epf_vhost_cfs_work() function that + * is scheduled + * + * This is a delayed work function to create configfs directory to perform EPF + * vhost specific initializations. This configfs directory will be a + * sub-directory to the directory created by the user to create pci_epf device. + */ +static void pci_epf_vhost_cfs_work(struct work_struct *work) +{ + struct epf_vhost *vhost = container_of(work, struct epf_vhost, + cfs_work.work); + struct pci_epf *epf = vhost->epf; + struct device *dev = &epf->dev; + struct config_group *group; + struct vhost_dev *vdev; + int ret; + + if (!epf->group) { + queue_delayed_work(kpcivhost_workqueue, &vhost->cfs_work, + msecs_to_jiffies(50)); + return; + } + + vdev = &vhost->vdev; + group = &vhost->group; + config_group_init_type_name(group, dev_name(dev), &pci_epf_vhost_cfs_type); + ret = configfs_register_group(epf->group, group); + if (ret) { + dev_err(dev, "Failed to register configfs group %s\n", dev_name(dev)); + return; + } +} + +/* pci_epf_vhost_probe - Initialize struct epf_vhost when a new EPF device is + * created + * @epf: Endpoint function device that is bound to this driver + * + * Probe function to initialize struct epf_vhost when a new EPF device is + * created. + */ +static int pci_epf_vhost_probe(struct pci_epf *epf) +{ + struct epf_vhost *vhost; + + vhost = kzalloc(sizeof(*vhost), GFP_KERNEL); + if (!vhost) + return -ENOMEM; + + epf->header = &epf_vhost_header; + vhost->epf = epf; + + epf_set_drvdata(epf, vhost); + INIT_DELAYED_WORK(&vhost->cmd_handler, pci_epf_vhost_cmd_handler); + INIT_DELAYED_WORK(&vhost->cfs_work, pci_epf_vhost_cfs_work); + queue_delayed_work(kpcivhost_workqueue, &vhost->cfs_work, + msecs_to_jiffies(50)); + + return 0; +} + +/* pci_epf_vhost_remove - Free the initializations performed by + * pci_epf_vhost_probe() + * @epf: Endpoint function device that is bound to this driver + * + * Free the initializations performed by pci_epf_vhost_probe(). + */ +static int pci_epf_vhost_remove(struct pci_epf *epf) +{ + struct epf_vhost *vhost; + + vhost = epf_get_drvdata(epf); + cancel_delayed_work_sync(&vhost->cfs_work); + + return 0; +} + +/* pci_epf_vhost_bind - Bind callback to initialize the PCIe EP controller + * @epf: Endpoint function device that is bound to the endpoint controller + * + * pci_epf_vhost_bind() is invoked when an endpoint controller is bound to + * endpoint function. This function initializes the endpoint controller + * with vhost endpoint function specific data. + */ +static int pci_epf_vhost_bind(struct pci_epf *epf) +{ + const struct pci_epc_features *epc_features; + struct epf_vhost *vhost; + struct pci_epc *epc; + struct device *dev; + int ret; + + vhost = epf_get_drvdata(epf); + dev = &epf->dev; + epc = epf->epc; + + epc_features = pci_epc_get_features(epc, epf->func_no); + if (!epc_features) { + dev_err(dev, "Fail to get EPC features\n"); + return -EINVAL; + } + vhost->epc_features = epc_features; + + ret = pci_epf_vhost_write_header(vhost); + if (ret) { + dev_err(dev, "Failed to bind VHOST config header\n"); + return ret; + } + + ret = pci_epf_vhost_configure_bar(vhost); + if (ret) { + dev_err(dev, "Failed to configure BAR\n"); + return ret; + } + + ret = pci_epf_vhost_configure_interrupts(vhost); + if (ret) { + dev_err(dev, "Failed to configure BAR\n"); + return ret; + } + + ret = pci_epf_vhost_register(vhost); + if (ret) { + dev_err(dev, "Failed to bind VHOST config header\n"); + return ret; + } + + queue_work(kpcivhost_workqueue, &vhost->cmd_handler.work); + + return ret; +} + +/* pci_epf_vhost_unbind - Inbind callback to cleanup the PCIe EP controller + * @epf: Endpoint function device that is bound to the endpoint controller + * + * pci_epf_vhost_unbind() is invoked when the binding between endpoint + * controller is removed from endpoint function. This will unregister vhost + * device and cancel pending cmd_handler work. + */ +static void pci_epf_vhost_unbind(struct pci_epf *epf) +{ + struct epf_vhost *vhost; + struct vhost_dev *vdev; + + vhost = epf_get_drvdata(epf); + vdev = &vhost->vdev; + + cancel_delayed_work_sync(&vhost->cmd_handler); + if (device_is_registered(&vdev->dev)) + vhost_unregister_device(vdev); +} + +static struct pci_epf_ops epf_ops = { + .bind = pci_epf_vhost_bind, + .unbind = pci_epf_vhost_unbind, +}; + +static const struct pci_epf_device_id pci_epf_vhost_ids[] = { + { + .name = "pci-epf-vhost", + }, + { }, +}; + +static struct pci_epf_driver epf_vhost_driver = { + .driver.name = "pci_epf_vhost", + .probe = pci_epf_vhost_probe, + .remove = pci_epf_vhost_remove, + .id_table = pci_epf_vhost_ids, + .ops = &epf_ops, + .owner = THIS_MODULE, +}; + +static int __init pci_epf_vhost_init(void) +{ + int ret; + + kpcivhost_workqueue = alloc_workqueue("kpcivhost", WQ_MEM_RECLAIM | + WQ_HIGHPRI, 0); + ret = pci_epf_register_driver(&epf_vhost_driver); + if (ret) { + pr_err("Failed to register pci epf vhost driver --> %d\n", ret); + return ret; + } + + return 0; +} +module_init(pci_epf_vhost_init); + +static void __exit pci_epf_vhost_exit(void) +{ + pci_epf_unregister_driver(&epf_vhost_driver); +} +module_exit(pci_epf_vhost_exit); + +MODULE_DESCRIPTION("PCI EPF VHOST DRIVER"); +MODULE_AUTHOR("Kishon Vijay Abraham I <kis...@ti.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/vhost/vhost_cfs.c b/drivers/vhost/vhost_cfs.c index ae46e71968f1..ab0393289200 100644 --- a/drivers/vhost/vhost_cfs.c +++ b/drivers/vhost/vhost_cfs.c @@ -18,12 +18,6 @@ static struct config_group *vhost_driver_group; /* VHOST device like PCIe EP, NTB etc., */ static struct config_group *vhost_device_group; -struct vhost_driver_item { - struct config_group group; - u32 vendor; - u32 device; -}; - struct vhost_driver_group { struct config_group group; }; @@ -33,13 +27,6 @@ struct vhost_device_item { struct vhost_dev *vdev; }; -static inline -struct vhost_driver_item *to_vhost_driver_item(struct config_item *item) -{ - return container_of(to_config_group(item), struct vhost_driver_item, - group); -} - static inline struct vhost_device_item *to_vhost_device_item(struct config_item *item) { diff --git a/include/linux/vhost.h b/include/linux/vhost.h index be9341ffd266..640650311310 100644 --- a/include/linux/vhost.h +++ b/include/linux/vhost.h @@ -74,6 +74,7 @@ struct vhost_virtqueue { struct vhost_dev *dev; enum vhost_type type; struct vringh vringh; + int index; void (*callback)(struct vhost_virtqueue *vq); void (*notify)(struct vhost_virtqueue *vq); @@ -148,6 +149,12 @@ struct vhost_msg_node { struct list_head node; }; +struct vhost_driver_item { + struct config_group group; + u32 vendor; + u32 device; +}; + enum vhost_notify_event { NOTIFY_SET_STATUS, NOTIFY_FINALIZE_FEATURES, @@ -230,6 +237,13 @@ static inline void *vhost_get_drvdata(struct vhost_dev *vdev) return dev_get_drvdata(&vdev->dev); } +static inline +struct vhost_driver_item *to_vhost_driver_item(struct config_item *item) +{ + return container_of(to_config_group(item), struct vhost_driver_item, + group); +} + int vhost_register_driver(struct vhost_driver *driver); void vhost_unregister_driver(struct vhost_driver *driver); int vhost_register_device(struct vhost_dev *vdev); -- 2.17.1