[5/6] vdpa: introduce virtio pci driver

Message ID	20200529080303.15449-6-jasowang@redhat.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <SRS0=rOkw=7L=vger.kernel.org=kvm-owner@kernel.org> From: Jason Wang <jasowang@redhat.com> To: mst@redhat.com, jasowang@redhat.com Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, rob.miller@broadcom.com, lingshan.zhu@intel.com, eperezma@redhat.com, lulu@redhat.com, shahafs@mellanox.com, hanand@xilinx.com, mhabets@solarflare.com, gdawar@xilinx.com, saugatm@xilinx.com, vmireyno@marvell.com, zhangweining@ruijie.com.cn, eli@mellanox.com Subject: [PATCH 5/6] vdpa: introduce virtio pci driver Date: Fri, 29 May 2020 16:03:02 +0800 Message-Id: <20200529080303.15449-6-jasowang@redhat.com> In-Reply-To: <20200529080303.15449-1-jasowang@redhat.com> References: <20200529080303.15449-1-jasowang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk
Series	vDPA: doorbell mapping \| expand [0/6] vDPA: doorbell mapping [1/6] vhost: allow device that does not depend on vhost worker [2/6] vhost: use mmgrab() instead of mmget() for non worker device [3/6] vdpa: introduce get_vq_notification method [4/6] vhost_vdpa: support doorbell mapping via mmap [5/6] vdpa: introduce virtio pci driver [6/6] vdpa: vp_vdpa: report doorbell location

diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig index e8140065c8a5..3f1bf8b6723d 100644 --- a/drivers/vdpa/Kconfig +++ b/drivers/vdpa/Kconfig @@ -28,4 +28,10 @@ config IFCVF To compile this driver as a module, choose M here: the module will be called ifcvf. +config VP_VDPA + tristate "Virtio PCI bridge vDPA driver" + depends on PCI_MSI + help + This kernel module that bridges virtio PCI device to vDPA bus. + endif # VDPA diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile index 8bbb686ca7a2..37d00f49b3bf 100644 --- a/drivers/vdpa/Makefile +++ b/drivers/vdpa/Makefile @@ -2,3 +2,4 @@ obj-$(CONFIG_VDPA) += vdpa.o obj-$(CONFIG_VDPA_SIM) += vdpa_sim/ obj-$(CONFIG_IFCVF) += ifcvf/ +obj-$(CONFIG_VP_VDPA) += vp_vdpa/ diff --git a/drivers/vdpa/vp_vdpa/Makefile b/drivers/vdpa/vp_vdpa/Makefile new file mode 100644 index 000000000000..231088d3af7d --- /dev/null +++ b/drivers/vdpa/vp_vdpa/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_VP_VDPA) += vp_vdpa.o diff --git a/drivers/vdpa/vp_vdpa/vp_vdpa.c b/drivers/vdpa/vp_vdpa/vp_vdpa.c new file mode 100644 index 000000000000..e59c310e2156 --- /dev/null +++ b/drivers/vdpa/vp_vdpa/vp_vdpa.c @@ -0,0 +1,583 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * vDPA bridge driver for modern virtio-pci device + * + * Copyright (c) 2020, Red Hat Inc. All rights reserved. + * Author: Jason Wang <jasowang@redhat.com> + * + * Based on virtio_pci_modern.c. + */ + +#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> + +/* TBD: read from config space */ +#define VP_VDPA_MAX_QUEUE 2 +#define VP_VDPA_DRIVER_NAME "vp_vdpa" + +#define VP_VDPA_FEATURES \ + (1ULL << VIRTIO_F_ANY_LAYOUT) | \ + (1ULL << VIRTIO_F_VERSION_1) | \ + (1ULL << VIRTIO_F_ORDER_PLATFORM) | \ + (1ULL << VIRTIO_F_IOMMU_PLATFORM) + +struct vp_vring { + void __iomem *notify; + char msix_name[256]; + struct vdpa_callback cb; + int irq; +}; + +struct vp_vdpa { + struct vdpa_device vdpa; + struct pci_dev *pdev; + + struct virtio_device_id id; + + struct vp_vring vring[VP_VDPA_MAX_QUEUE]; + + /* The IO mapping for the PCI config space */ + void __iomem * const *base; + struct virtio_pci_common_cfg __iomem *common; + void __iomem *device; + /* Base of vq notifications */ + void __iomem *notify; + + /* Multiplier for queue_notify_off. */ + u32 notify_off_multiplier; + + int modern_bars; + int vectors; +}; + +static struct vp_vdpa *vdpa_to_vp(struct vdpa_device *vdpa) +{ + return container_of(vdpa, struct vp_vdpa, vdpa); +} + +/* + * Type-safe wrappers for io accesses. + * Use these to enforce at compile time the following spec requirement: + * + * The driver MUST access each field using the “natural” access + * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses + * for 16-bit fields and 8-bit accesses for 8-bit fields. + */ +static inline u8 vp_ioread8(u8 __iomem *addr) +{ + return ioread8(addr); +} +static inline u16 vp_ioread16 (__le16 __iomem *addr) +{ + return ioread16(addr); +} + +static inline u32 vp_ioread32(__le32 __iomem *addr) +{ + return ioread32(addr); +} + +static inline void vp_iowrite8(u8 value, u8 __iomem *addr) +{ + iowrite8(value, addr); +} + +static inline void vp_iowrite16(u16 value, __le16 __iomem *addr) +{ + iowrite16(value, addr); +} + +static inline void vp_iowrite32(u32 value, __le32 __iomem *addr) +{ + iowrite32(value, addr); +} + +static void vp_iowrite64_twopart(u64 val, + __le32 __iomem *lo, __le32 __iomem *hi) +{ + vp_iowrite32((u32)val, lo); + vp_iowrite32(val >> 32, hi); +} + +static int find_capability(struct pci_dev *dev, u8 cfg_type, + u32 ioresource_types, int *bars) +{ + int pos; + + for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); + pos > 0; + pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { + u8 type, bar; + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + cfg_type), + &type); + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + bar), + &bar); + + /* Ignore structures with reserved BAR values */ + if (bar > 0x5) + continue; + + if (type == cfg_type) { + if (pci_resource_len(dev, bar) && + pci_resource_flags(dev, bar) & ioresource_types) { + *bars |= (1 << bar); + return pos; + } + } + } + return 0; +} + +static void __iomem *map_capability(struct vp_vdpa *vp_vdpa, int off) +{ + struct pci_dev *pdev = vp_vdpa->pdev; + u32 offset; + u8 bar; + + pci_read_config_byte(pdev, + off + offsetof(struct virtio_pci_cap, bar), + &bar); + pci_read_config_dword(pdev, + off + offsetof(struct virtio_pci_cap, offset), + &offset); + + return vp_vdpa->base[bar] + offset; +} + +static u64 vp_vdpa_get_features(struct vdpa_device *vdpa) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + u64 features; + + vp_iowrite32(0, &vp_vdpa->common->device_feature_select); + features = vp_ioread32(&vp_vdpa->common->device_feature); + vp_iowrite32(1, &vp_vdpa->common->device_feature_select); + features |= ((u64)vp_ioread32(&vp_vdpa->common->device_feature) << 32); + features &= VP_VDPA_FEATURES; + + return features; +} + +static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + vp_iowrite32(0, &vp_vdpa->common->guest_feature_select); + vp_iowrite32((u32)features, &vp_vdpa->common->guest_feature); + vp_iowrite32(1, &vp_vdpa->common->guest_feature_select); + vp_iowrite32(features >> 32, &vp_vdpa->common->guest_feature); + + return 0; +} + +static u8 vp_vdpa_get_status(struct vdpa_device *vdpa) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + return vp_ioread8(&vp_vdpa->common->device_status); +} + +static void vp_vdpa_free_irq(struct vp_vdpa *vp_vdpa) +{ + struct pci_dev *pdev = vp_vdpa->pdev; + int i; + + for (i = 0; i < VP_VDPA_MAX_QUEUE; i++) { + if (vp_vdpa->vring[i].irq != -1) { + vp_iowrite16(i, &vp_vdpa->common->queue_select); + vp_iowrite16(VIRTIO_MSI_NO_VECTOR, + &vp_vdpa->common->queue_msix_vector); + devm_free_irq(&pdev->dev, vp_vdpa->vring[i].irq, + &vp_vdpa->vring[i]); + vp_vdpa->vring[i].irq = -1; + } + } + + if (vp_vdpa->vectors) { + pci_free_irq_vectors(pdev); + vp_vdpa->vectors = 0; + } +} + +static irqreturn_t vp_vdpa_intr_handler(int irq, void *arg) +{ + struct vp_vring *vring = arg; + + if (vring->cb.callback) + return vring->cb.callback(vring->cb.private); + + return IRQ_HANDLED; +} + +static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa) +{ + struct pci_dev *pdev = vp_vdpa->pdev; + int i, ret, irq; + + ret = pci_alloc_irq_vectors(pdev, VP_VDPA_MAX_QUEUE, + VP_VDPA_MAX_QUEUE, PCI_IRQ_MSIX); + if (ret != VP_VDPA_MAX_QUEUE) { + dev_err(&pdev->dev, "vp_vdpa: fail to allocate irq vectors\n"); + return ret; + } + + vp_vdpa->vectors = VP_VDPA_MAX_QUEUE; + + for (i = 0; i < VP_VDPA_MAX_QUEUE; i++) { + snprintf(vp_vdpa->vring[i].msix_name, 256, + "vp-vdpa[%s]-%d\n", pci_name(pdev), i); + irq = pci_irq_vector(pdev, i); + ret = devm_request_irq(&pdev->dev, irq, + vp_vdpa_intr_handler, + 0, vp_vdpa->vring[i].msix_name, + &vp_vdpa->vring[i]); + if (ret) { + dev_err(&pdev->dev, "vp_vdpa: fail to request irq for vq %d\n", i); + goto err; + } + vp_iowrite16(i, &vp_vdpa->common->queue_select); + vp_iowrite16(i, &vp_vdpa->common->queue_msix_vector); + vp_vdpa->vring[i].irq = irq; + } + + return 0; +err: + vp_vdpa_free_irq(vp_vdpa); + return ret; +} + +static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + u8 s = vp_vdpa_get_status(vdpa); + + if (status & VIRTIO_CONFIG_S_DRIVER_OK && + !(s & VIRTIO_CONFIG_S_DRIVER_OK)) { + vp_vdpa_request_irq(vp_vdpa); + } + + vp_iowrite8(status, &vp_vdpa->common->device_status); + + if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) && + (s & VIRTIO_CONFIG_S_DRIVER_OK)) + vp_vdpa_free_irq(vp_vdpa); +} + +static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + return vp_ioread16(&vp_vdpa->common->queue_size); +} + +static u64 vp_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid) +{ + return 0; +} + +static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid, + u64 num) +{ + /* Note that this is not supported by virtio specification, so + * we return -ENOTSUPP here. This means we can't support live + * migration, vhost device start/stop. + */ + + return -ENOTSUPP; +} + +static void vp_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 qid, + struct vdpa_callback *cb) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + vp_vdpa->vring[qid].cb = *cb; +} + +static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa, + u16 qid, bool ready) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + vp_iowrite16(qid, &vp_vdpa->common->queue_select); + vp_iowrite16(ready, &vp_vdpa->common->queue_enable); +} + +static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + vp_iowrite16(qid, &vp_vdpa->common->queue_select); + + return vp_ioread16(&vp_vdpa->common->queue_enable); +} + +static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid, + u32 num) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + vp_iowrite16(num, &vp_vdpa->common->queue_size); +} + +static int vp_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 qid, + u64 desc_area, u64 driver_area, + u64 device_area) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + struct virtio_pci_common_cfg __iomem *cfg = vp_vdpa->common; + + vp_iowrite16(qid, &cfg->queue_select); + vp_iowrite64_twopart(desc_area, + &cfg->queue_desc_lo, &cfg->queue_desc_hi); + vp_iowrite64_twopart(driver_area, + &cfg->queue_avail_lo, &cfg->queue_avail_hi); + vp_iowrite64_twopart(device_area, + &cfg->queue_used_lo, &cfg->queue_used_hi); + + return 0; +} + +static void vp_vdpa_kick_vq(struct vdpa_device *vdpa, u16 qid) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + vp_iowrite16(qid, vp_vdpa->vring[qid].notify); +} + +static u32 vp_vdpa_get_generation(struct vdpa_device *vdpa) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + return vp_ioread8(&vp_vdpa->common->config_generation); +} + +static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + return vp_vdpa->id.device; +} + +static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + + return vp_vdpa->id.vendor; +} + +static u32 vp_vdpa_get_vq_align(struct vdpa_device *vdpa) +{ + return PAGE_SIZE; +} + +static void vp_vdpa_get_config(struct vdpa_device *vdpa, + unsigned int offset, + void *buf, unsigned int len) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + u8 old, new; + u8 *p; + int i; + + do { + old = vp_ioread8(&vp_vdpa->common->config_generation); + p = buf; + for (i = 0; i < len; i++) + *p++ = vp_ioread8(vp_vdpa->device + offset + i); + + new = vp_ioread8(&vp_vdpa->common->config_generation); + } while (old != new); +} + +static void vp_vdpa_set_config(struct vdpa_device *vdpa, + unsigned int offset, const void *buf, + unsigned int len) +{ + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa); + const u8 *p = buf; + int i; + + for (i = 0; i < len; i++) + vp_iowrite8(*p++, vp_vdpa->device + offset + i); +} + +static void vp_vdpa_set_config_cb(struct vdpa_device *vdpa, + struct vdpa_callback *cb) +{ + /* We don't support config interrupt */ +} + +static const struct vdpa_config_ops vp_vdpa_ops = { + .get_features = vp_vdpa_get_features, + .set_features = vp_vdpa_set_features, + .get_status = vp_vdpa_get_status, + .set_status = vp_vdpa_set_status, + .get_vq_num_max = vp_vdpa_get_vq_num_max, + .get_vq_state = vp_vdpa_get_vq_state, + .set_vq_state = vp_vdpa_set_vq_state, + .set_vq_cb = vp_vdpa_set_vq_cb, + .set_vq_ready = vp_vdpa_set_vq_ready, + .get_vq_ready = vp_vdpa_get_vq_ready, + .set_vq_num = vp_vdpa_set_vq_num, + .set_vq_address = vp_vdpa_set_vq_address, + .kick_vq = vp_vdpa_kick_vq, + .get_generation = vp_vdpa_get_generation, + .get_device_id = vp_vdpa_get_device_id, + .get_vendor_id = vp_vdpa_get_vendor_id, + .get_vq_align = vp_vdpa_get_vq_align, + .get_config = vp_vdpa_get_config, + .set_config = vp_vdpa_set_config, + .set_config_cb = vp_vdpa_set_config_cb, +}; + +static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + struct device *dev = &pdev->dev; + struct vp_vdpa *vp_vdpa; + int common, notify, device, ret, i; + struct virtio_device_id virtio_id; + u16 notify_off; + + /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */ + if (pdev->device < 0x1000 || pdev->device > 0x107f) + return -ENODEV; + + if (pdev->device < 0x1040) { + /* Transitional devices: use the PCI subsystem device id as + * virtio device id, same as legacy driver always did. + */ + virtio_id.device = pdev->subsystem_device; + } else { + /* Modern devices: simply use PCI device id, but start from 0x1040. */ + virtio_id.device = pdev->device - 0x1040; + } + virtio_id.vendor = pdev->subsystem_vendor; + + ret = pcim_enable_device(pdev); + if (ret) { + dev_err(dev, "vp_vdpa: Fail to enable PCI device\n"); + return ret; + } + + vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa, + dev, &vp_vdpa_ops); + if (vp_vdpa == NULL) { + dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n"); + return -ENOMEM; + } + + pci_set_master(pdev); + pci_set_drvdata(pdev, vp_vdpa); + + vp_vdpa->pdev = pdev; + vp_vdpa->vdpa.dma_dev = &pdev->dev; + + common = find_capability(pdev, VIRTIO_PCI_CAP_COMMON_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &vp_vdpa->modern_bars); + if (!common) { + dev_err(&pdev->dev, + "vp_vdpa: legacy device is not supported\n"); + ret = -ENODEV; + goto err; + } + + notify = find_capability(pdev, VIRTIO_PCI_CAP_NOTIFY_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &vp_vdpa->modern_bars); + if (!notify) { + dev_err(&pdev->dev, + "vp_vdpa: missing notification capabilities\n"); + ret = -EINVAL; + goto err; + } + + device = find_capability(pdev, VIRTIO_PCI_CAP_DEVICE_CFG, + IORESOURCE_IO | IORESOURCE_MEM, + &vp_vdpa->modern_bars); + if (!device) { + dev_err(&pdev->dev, + "vp_vdpa: missing device capabilities\n"); + ret = -EINVAL; + goto err; + } + + ret = pcim_iomap_regions(pdev, vp_vdpa->modern_bars, + VP_VDPA_DRIVER_NAME); + if (ret) + goto err; + + vp_vdpa->base = pcim_iomap_table(pdev); + + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (ret) + ret = dma_set_mask_and_coherent(&pdev->dev, + DMA_BIT_MASK(32)); + if (ret) + dev_warn(&pdev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); + + vp_vdpa->device = map_capability(vp_vdpa, device); + vp_vdpa->notify = map_capability(vp_vdpa, notify); + vp_vdpa->common = map_capability(vp_vdpa, common); + vp_vdpa->id = virtio_id; + + ret = vdpa_register_device(&vp_vdpa->vdpa); + if (ret) { + dev_err(&pdev->dev, "Failed to register to vdpa bus\n"); + goto err; + } + + pci_read_config_dword(pdev, notify + sizeof(struct virtio_pci_cap), + &vp_vdpa->notify_off_multiplier); + + for (i = 0; i < VP_VDPA_MAX_QUEUE; i++) { + vp_iowrite16(i, &vp_vdpa->common->queue_select); + notify_off = vp_ioread16(&vp_vdpa->common->queue_notify_off); + vp_vdpa->vring[i].irq = -1; + vp_vdpa->vring[i].notify = vp_vdpa->notify + + notify_off * vp_vdpa->notify_off_multiplier; + } + + return 0; + +err: + put_device(&vp_vdpa->vdpa.dev); + return ret; +} + +static void vp_vdpa_remove(struct pci_dev *pdev) +{ + struct vp_vdpa *vp_vdpa = pci_get_drvdata(pdev); + + vdpa_unregister_device(&vp_vdpa->vdpa); +} + +static const struct pci_device_id vp_vdpa_id_table[] = { + { PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_ANY_ID) }, + { 0 } +}; + +MODULE_DEVICE_TABLE(pci, vp_vdpa_id_table); + +static struct pci_driver vp_vdpa_driver = { + .name = "vp-vdpa", + .id_table = vp_vdpa_id_table, + .probe = vp_vdpa_probe, + .remove = vp_vdpa_remove, +}; + +module_pci_driver(vp_vdpa_driver); + +MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>"); +MODULE_DESCRIPTION("vp-vdpa"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("1");

[5/6] vdpa: introduce virtio pci driver

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