[PATCH v2 5/5] eni_vdpa: add vDPA driver for Alibaba ENI
From: Wu Zongyong
Date: Tue Sep 14 2021 - 08:26:14 EST
This patch adds a new vDPA driver for Alibaba ENI(Elastic Network
Interface) which is build upon virtio 0.9.5 specification.
Signed-off-by: Wu Zongyong <wuzongyong@xxxxxxxxxxxxxxxxx>
---
drivers/vdpa/Kconfig | 8 +
drivers/vdpa/Makefile | 1 +
drivers/vdpa/alibaba/Makefile | 3 +
drivers/vdpa/alibaba/eni_vdpa.c | 537 ++++++++++++++++++++++++++++++++
4 files changed, 549 insertions(+)
create mode 100644 drivers/vdpa/alibaba/Makefile
create mode 100644 drivers/vdpa/alibaba/eni_vdpa.c
diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
index 3d91982d8371..9587b9177b05 100644
--- a/drivers/vdpa/Kconfig
+++ b/drivers/vdpa/Kconfig
@@ -78,4 +78,12 @@ config VP_VDPA
help
This kernel module bridges virtio PCI device to vDPA bus.
+config ALIBABA_ENI_VDPA
+ tristate "vDPA driver for Alibaba ENI"
+ select VIRTIO_PCI_LEGACY_LIB
+ depends on PCI_MSI
+ help
+ VDPA driver for Alibaba ENI(Elastic Network Interface) which is build upon
+ virtio 0.9.5 specification.
+
endif # VDPA
diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile
index f02ebed33f19..15665563a7f4 100644
--- a/drivers/vdpa/Makefile
+++ b/drivers/vdpa/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_VDPA_USER) += vdpa_user/
obj-$(CONFIG_IFCVF) += ifcvf/
obj-$(CONFIG_MLX5_VDPA) += mlx5/
obj-$(CONFIG_VP_VDPA) += virtio_pci/
+obj-$(CONFIG_ALIBABA_ENI_VDPA) += alibaba/
diff --git a/drivers/vdpa/alibaba/Makefile b/drivers/vdpa/alibaba/Makefile
new file mode 100644
index 000000000000..ef4aae69f87a
--- /dev/null
+++ b/drivers/vdpa/alibaba/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_ALIBABA_ENI_VDPA) += eni_vdpa.o
+
diff --git a/drivers/vdpa/alibaba/eni_vdpa.c b/drivers/vdpa/alibaba/eni_vdpa.c
new file mode 100644
index 000000000000..38e85a5dd62e
--- /dev/null
+++ b/drivers/vdpa/alibaba/eni_vdpa.c
@@ -0,0 +1,537 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vDPA bridge driver for Alibaba ENI(Elastic Network Interface)
+ *
+ * Copyright (c) 2021, Alibaba Inc. All rights reserved.
+ * Author: Wu Zongyong <wuzongyong@xxxxxxxxxxxxxxxxx>
+ *
+ */
+
+#include "asm-generic/errno-base.h"
+#include "asm-generic/errno.h"
+#include "linux/irqreturn.h"
+#include "linux/kernel.h"
+#include "linux/pci_ids.h"
+#include "linux/virtio_config.h"
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/vdpa.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_ring.h>
+#include <linux/virtio_pci.h>
+#include <linux/virtio_pci_legacy.h>
+#include <uapi/linux/virtio_net.h>
+
+#define ENI_MSIX_NAME_SIZE 256
+
+#define ENI_ERR(pdev, fmt, ...) \
+ dev_err(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
+#define ENI_DBG(pdev, fmt, ...) \
+ dev_dbg(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
+#define ENI_INFO(pdev, fmt, ...) \
+ dev_info(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
+
+struct eni_vring {
+ void __iomem *notify;
+ char msix_name[ENI_MSIX_NAME_SIZE];
+ struct vdpa_callback cb;
+ int irq;
+};
+
+struct eni_vdpa {
+ struct vdpa_device vdpa;
+ struct virtio_pci_legacy_device ldev;
+ struct eni_vring *vring;
+ struct vdpa_callback config_cb;
+ char msix_name[ENI_MSIX_NAME_SIZE];
+ int config_irq;
+ int queues;
+ int vectors;
+};
+
+static struct eni_vdpa *vdpa_to_eni(struct vdpa_device *vdpa)
+{
+ return container_of(vdpa, struct eni_vdpa, vdpa);
+}
+
+static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+
+ return &eni_vdpa->ldev;
+}
+
+static u64 eni_vdpa_get_features(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return vp_legacy_get_features(ldev);
+}
+
+static int eni_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ vp_legacy_set_features(ldev, (u32)features);
+
+ return 0;
+}
+
+static u8 eni_vdpa_get_status(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return vp_legacy_get_status(ldev);
+}
+
+static int eni_vdpa_get_vq_irq(struct vdpa_device *vdpa, u16 idx)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+ int irq = eni_vdpa->vring[idx].irq;
+
+ if (irq == VIRTIO_MSI_NO_VECTOR)
+ return -EINVAL;
+
+ return irq;
+}
+
+static void eni_vdpa_free_irq(struct eni_vdpa *eni_vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
+ struct pci_dev *pdev = ldev->pci_dev;
+ int i;
+
+ for (i = 0; i < eni_vdpa->queues; i++) {
+ if (eni_vdpa->vring[i].irq != VIRTIO_MSI_NO_VECTOR) {
+ vp_legacy_queue_vector(ldev, i, VIRTIO_MSI_NO_VECTOR);
+ devm_free_irq(&pdev->dev, eni_vdpa->vring[i].irq,
+ &eni_vdpa->vring[i]);
+ eni_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
+ }
+ }
+
+ if (eni_vdpa->config_irq != VIRTIO_MSI_NO_VECTOR) {
+ vp_legacy_config_vector(ldev, VIRTIO_MSI_NO_VECTOR);
+ devm_free_irq(&pdev->dev, eni_vdpa->config_irq, eni_vdpa);
+ eni_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
+ }
+
+ if (eni_vdpa->vectors) {
+ pci_free_irq_vectors(pdev);
+ eni_vdpa->vectors = 0;
+ }
+}
+
+static irqreturn_t eni_vdpa_vq_handler(int irq, void *arg)
+{
+ struct eni_vring *vring = arg;
+
+ if (vring->cb.callback)
+ return vring->cb.callback(vring->cb.private);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t eni_vdpa_config_handler(int irq, void *arg)
+{
+ struct eni_vdpa *eni_vdpa = arg;
+
+ if (eni_vdpa->config_cb.callback)
+ return eni_vdpa->config_cb.callback(eni_vdpa->config_cb.private);
+
+ return IRQ_HANDLED;
+}
+
+static int eni_vdpa_request_irq(struct eni_vdpa *eni_vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
+ struct pci_dev *pdev = ldev->pci_dev;
+ int i, ret, irq;
+ int queues = eni_vdpa->queues;
+ int vectors = queues + 1;
+
+ ret = pci_alloc_irq_vectors(pdev, vectors, vectors, PCI_IRQ_MSIX);
+ if (ret != vectors) {
+ ENI_ERR(pdev,
+ "failed to allocate irq vectors want %d but %d\n",
+ vectors, ret);
+ return ret;
+ }
+
+ eni_vdpa->vectors = vectors;
+
+ for (i = 0; i < queues; i++) {
+ snprintf(eni_vdpa->vring[i].msix_name, ENI_MSIX_NAME_SIZE,
+ "eni-vdpa[%s]-%d\n", pci_name(pdev), i);
+ irq = pci_irq_vector(pdev, i);
+ ret = devm_request_irq(&pdev->dev, irq,
+ eni_vdpa_vq_handler,
+ 0, eni_vdpa->vring[i].msix_name,
+ &eni_vdpa->vring[i]);
+ if (ret) {
+ ENI_ERR(pdev, "failed to request irq for vq %d\n", i);
+ goto err;
+ }
+ vp_legacy_queue_vector(ldev, i, i);
+ eni_vdpa->vring[i].irq = irq;
+ }
+
+ snprintf(eni_vdpa->msix_name, ENI_MSIX_NAME_SIZE, "eni-vdpa[%s]-config\n",
+ pci_name(pdev));
+ irq = pci_irq_vector(pdev, queues);
+ ret = devm_request_irq(&pdev->dev, irq, eni_vdpa_config_handler, 0,
+ eni_vdpa->msix_name, eni_vdpa);
+ if (ret) {
+ ENI_ERR(pdev, "failed to request irq for config vq %d\n", i);
+ goto err;
+ }
+ vp_legacy_config_vector(ldev, queues);
+ eni_vdpa->config_irq = irq;
+
+ return 0;
+err:
+ eni_vdpa_free_irq(eni_vdpa);
+ return ret;
+}
+
+static void eni_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+ struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
+ u8 s = eni_vdpa_get_status(vdpa);
+
+ if (status & VIRTIO_CONFIG_S_DRIVER_OK &&
+ !(s & VIRTIO_CONFIG_S_DRIVER_OK)) {
+ eni_vdpa_request_irq(eni_vdpa);
+ }
+
+ vp_legacy_set_status(ldev, status);
+
+ if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+ (s & VIRTIO_CONFIG_S_DRIVER_OK))
+ eni_vdpa_free_irq(eni_vdpa);
+}
+
+static int eni_vdpa_reset(struct vdpa_device *vdpa)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+ struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
+ u8 s = eni_vdpa_get_status(vdpa);
+
+ vp_legacy_set_status(ldev, 0);
+
+ if (s & VIRTIO_CONFIG_S_DRIVER_OK)
+ eni_vdpa_free_irq(eni_vdpa);
+
+ return 0;
+}
+
+static u16 eni_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return vp_legacy_get_queue_size(ldev, 0);
+}
+
+static int eni_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid,
+ struct vdpa_vq_state *state)
+{
+ return -EOPNOTSUPP;
+}
+
+static int eni_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
+ const struct vdpa_vq_state *state)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+ const struct vdpa_vq_state_split *split = &state->split;
+
+ /* ENI is build upon virtio-pci specfication which not support
+ * to set state of virtqueue. But if the state is equal to the
+ * device initial state by chance, we can let it go.
+ */
+ if (!vp_legacy_get_queue_enable(ldev, qid)
+ && split->avail_index == 0)
+ return 0;
+
+ return -EOPNOTSUPP;
+}
+
+
+static void eni_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 qid,
+ struct vdpa_callback *cb)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+
+ eni_vdpa->vring[qid].cb = *cb;
+}
+
+static void eni_vdpa_set_vq_ready(struct vdpa_device *vdpa, u16 qid,
+ bool ready)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ /* ENI is a legacy virtio-pci device. This is not supported
+ * by specification. But we can disable virtqueue by setting
+ * address to 0.
+ */
+ if (!ready)
+ vp_legacy_set_queue_address(ldev, qid, 0);
+}
+
+static bool eni_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return vp_legacy_get_queue_enable(ldev, qid);
+}
+
+static void eni_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
+ u32 num)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+ struct pci_dev *pdev = ldev->pci_dev;
+ u16 n = vp_legacy_get_queue_size(ldev, qid);
+
+ /* ENI is a legacy virtio-pci device which not allow to change
+ * virtqueue size. Just report a error if someone tries to
+ * change it.
+ */
+ if (num != n)
+ ENI_ERR(pdev,
+ "not support to set vq %u fixed num %u to %u\n",
+ qid, n, num);
+}
+
+static int eni_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 qid,
+ u64 desc_area, u64 driver_area,
+ u64 device_area)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+ u32 pfn = desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT;
+
+ vp_legacy_set_queue_address(ldev, qid, pfn);
+
+ return 0;
+}
+
+static void eni_vdpa_kick_vq(struct vdpa_device *vdpa, u16 qid)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+
+ iowrite16(qid, eni_vdpa->vring[qid].notify);
+}
+
+static u32 eni_vdpa_get_device_id(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return ldev->id.device;
+}
+
+static u32 eni_vdpa_get_vendor_id(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return ldev->id.vendor;
+}
+
+static u32 eni_vdpa_get_vq_align(struct vdpa_device *vdpa)
+{
+ return PAGE_SIZE;
+}
+
+static size_t eni_vdpa_get_config_size(struct vdpa_device *vdpa)
+{
+ return sizeof(struct virtio_net_config);
+}
+
+
+static void eni_vdpa_get_config(struct vdpa_device *vdpa,
+ unsigned int offset,
+ void *buf, unsigned int len)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+ struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
+ void __iomem *ioaddr = ldev->ioaddr +
+ VIRTIO_PCI_CONFIG_OFF(eni_vdpa->vectors) +
+ offset;
+ u8 *p = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ *p++ = ioread8(ioaddr + i);
+}
+
+static void eni_vdpa_set_config(struct vdpa_device *vdpa,
+ unsigned int offset, const void *buf,
+ unsigned int len)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+ struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
+ void __iomem *ioaddr = ldev->ioaddr +
+ VIRTIO_PCI_CONFIG_OFF(eni_vdpa->vectors) +
+ offset;
+ const u8 *p = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ iowrite8(*p++, ioaddr + i);
+}
+
+static void eni_vdpa_set_config_cb(struct vdpa_device *vdpa,
+ struct vdpa_callback *cb)
+{
+ struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
+
+ eni_vdpa->config_cb = *cb;
+}
+
+static const struct vdpa_config_ops eni_vdpa_ops = {
+ .get_features = eni_vdpa_get_features,
+ .set_features = eni_vdpa_set_features,
+ .get_status = eni_vdpa_get_status,
+ .set_status = eni_vdpa_set_status,
+ .reset = eni_vdpa_reset,
+ .get_vq_num_max = eni_vdpa_get_vq_num_max,
+ .get_vq_state = eni_vdpa_get_vq_state,
+ .set_vq_state = eni_vdpa_set_vq_state,
+ .set_vq_cb = eni_vdpa_set_vq_cb,
+ .set_vq_ready = eni_vdpa_set_vq_ready,
+ .get_vq_ready = eni_vdpa_get_vq_ready,
+ .set_vq_num = eni_vdpa_set_vq_num,
+ .set_vq_address = eni_vdpa_set_vq_address,
+ .kick_vq = eni_vdpa_kick_vq,
+ .get_device_id = eni_vdpa_get_device_id,
+ .get_vendor_id = eni_vdpa_get_vendor_id,
+ .get_vq_align = eni_vdpa_get_vq_align,
+ .get_config_size = eni_vdpa_get_config_size,
+ .get_config = eni_vdpa_get_config,
+ .set_config = eni_vdpa_set_config,
+ .set_config_cb = eni_vdpa_set_config_cb,
+ .get_vq_irq = eni_vdpa_get_vq_irq,
+};
+
+
+static u16 eni_vdpa_get_num_queues(struct eni_vdpa *eni_vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
+ u32 features = vp_legacy_get_features(ldev);
+ u16 num = 2;
+
+ if (features & BIT_ULL(VIRTIO_NET_F_MQ)) {
+ __virtio16 max_virtqueue_pairs;
+
+ eni_vdpa_get_config(&eni_vdpa->vdpa,
+ offsetof(struct virtio_net_config, max_virtqueue_pairs),
+ &max_virtqueue_pairs,
+ sizeof(max_virtqueue_pairs));
+ num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
+ max_virtqueue_pairs);
+ }
+
+ if (features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ))
+ num += 1;
+
+ return num;
+}
+
+static void eni_vdpa_free_irq_vectors(void *data)
+{
+ pci_free_irq_vectors(data);
+}
+
+static int eni_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct device *dev = &pdev->dev;
+ struct eni_vdpa *eni_vdpa;
+ struct virtio_pci_legacy_device *ldev;
+ int ret, i;
+
+ ret = pcim_enable_device(pdev);
+ if (ret)
+ return ret;
+
+ eni_vdpa = vdpa_alloc_device(struct eni_vdpa, vdpa,
+ dev, &eni_vdpa_ops, NULL, false);
+ if (IS_ERR(eni_vdpa)) {
+ ENI_ERR(pdev, "failed to allocate vDPA structure\n");
+ return PTR_ERR(eni_vdpa);
+ }
+
+ ldev = &eni_vdpa->ldev;
+ ldev->pci_dev = pdev;
+
+ ret = vp_legacy_probe(ldev);
+ if (ret) {
+ ENI_ERR(pdev, "failed to probe legacy PCI device\n");
+ goto err;
+ }
+
+ pci_set_master(pdev);
+ pci_set_drvdata(pdev, eni_vdpa);
+
+ eni_vdpa->vdpa.dma_dev = &pdev->dev;
+ eni_vdpa->queues = eni_vdpa_get_num_queues(eni_vdpa);
+
+ ret = devm_add_action_or_reset(dev, eni_vdpa_free_irq_vectors, pdev);
+ if (ret) {
+ ENI_ERR(pdev,
+ "failed for adding devres for freeing irq vectors\n");
+ goto err;
+ }
+
+ eni_vdpa->vring = devm_kcalloc(&pdev->dev, eni_vdpa->queues,
+ sizeof(*eni_vdpa->vring),
+ GFP_KERNEL);
+ if (!eni_vdpa->vring) {
+ ret = -ENOMEM;
+ ENI_ERR(pdev, "fail to allocate virtqueues\n");
+ goto err;
+ }
+
+ for (i = 0; i < eni_vdpa->queues; i++) {
+ eni_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
+ eni_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
+ }
+ eni_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
+
+ ret = vdpa_register_device(&eni_vdpa->vdpa, eni_vdpa->queues);
+ if (ret) {
+ ENI_ERR(pdev, "failed to register to vdpa bus\n");
+ goto err;
+ }
+
+ return 0;
+
+err:
+ put_device(&eni_vdpa->vdpa.dev);
+ return ret;
+}
+
+static void eni_vdpa_remove(struct pci_dev *pdev)
+{
+ struct eni_vdpa *eni_vdpa = pci_get_drvdata(pdev);
+
+ vdpa_unregister_device(&eni_vdpa->vdpa);
+ vp_legacy_remove(&eni_vdpa->ldev);
+}
+
+static struct pci_device_id eni_pci_ids[] = {
+ { PCI_VENDOR_ID_REDHAT_QUMRANET, VIRTIO_TRANS_ID_NET },
+ { 0 },
+};
+
+static struct pci_driver eni_vdpa_driver = {
+ .name = "alibaba-eni-vdpa",
+ .id_table = eni_pci_ids,
+ .probe = eni_vdpa_probe,
+ .remove = eni_vdpa_remove,
+};
+
+module_pci_driver(eni_vdpa_driver);
+
+MODULE_AUTHOR("Wu Zongyong <wuzongyong@xxxxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Alibaba ENI vDPA driver");
+MODULE_LICENSE("GPL v2");
--
2.31.1