From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/virtio/virtio_pci_modern.c | 556 +++++++++++++++++++++++++++++++++++++ 1 file changed, 556 insertions(+) create mode 100644 drivers/virtio/virtio_pci_modern.c (limited to 'drivers/virtio/virtio_pci_modern.c') diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c new file mode 100644 index 000000000..edf2e1801 --- /dev/null +++ b/drivers/virtio/virtio_pci_modern.c @@ -0,0 +1,556 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio PCI driver - modern (virtio 1.0) device support + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * Copyright Red Hat, Inc. 2014 + * + * Authors: + * Anthony Liguori + * Rusty Russell + * Michael S. Tsirkin + */ + +#include +#define VIRTIO_PCI_NO_LEGACY +#define VIRTIO_RING_NO_LEGACY +#include "virtio_pci_common.h" + +static u64 vp_get_features(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + return vp_modern_get_features(&vp_dev->mdev); +} + +static void vp_transport_features(struct virtio_device *vdev, u64 features) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct pci_dev *pci_dev = vp_dev->pci_dev; + + if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && + pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) + __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); + + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); +} + +/* virtio config->finalize_features() implementation */ +static int vp_finalize_features(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + u64 features = vdev->features; + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + /* Give virtio_pci a chance to accept features. */ + vp_transport_features(vdev, features); + + if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) { + dev_err(&vdev->dev, "virtio: device uses modern interface " + "but does not have VIRTIO_F_VERSION_1\n"); + return -EINVAL; + } + + vp_modern_set_features(&vp_dev->mdev, vdev->features); + + return 0; +} + +/* virtio config->get() implementation */ +static void vp_get(struct virtio_device *vdev, unsigned int offset, + void *buf, unsigned int len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + void __iomem *device = mdev->device; + u8 b; + __le16 w; + __le32 l; + + BUG_ON(offset + len > mdev->device_len); + + switch (len) { + case 1: + b = ioread8(device + offset); + memcpy(buf, &b, sizeof b); + break; + case 2: + w = cpu_to_le16(ioread16(device + offset)); + memcpy(buf, &w, sizeof w); + break; + case 4: + l = cpu_to_le32(ioread32(device + offset)); + memcpy(buf, &l, sizeof l); + break; + case 8: + l = cpu_to_le32(ioread32(device + offset)); + memcpy(buf, &l, sizeof l); + l = cpu_to_le32(ioread32(device + offset + sizeof l)); + memcpy(buf + sizeof l, &l, sizeof l); + break; + default: + BUG(); + } +} + +/* the config->set() implementation. it's symmetric to the config->get() + * implementation */ +static void vp_set(struct virtio_device *vdev, unsigned int offset, + const void *buf, unsigned int len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + void __iomem *device = mdev->device; + u8 b; + __le16 w; + __le32 l; + + BUG_ON(offset + len > mdev->device_len); + + switch (len) { + case 1: + memcpy(&b, buf, sizeof b); + iowrite8(b, device + offset); + break; + case 2: + memcpy(&w, buf, sizeof w); + iowrite16(le16_to_cpu(w), device + offset); + break; + case 4: + memcpy(&l, buf, sizeof l); + iowrite32(le32_to_cpu(l), device + offset); + break; + case 8: + memcpy(&l, buf, sizeof l); + iowrite32(le32_to_cpu(l), device + offset); + memcpy(&l, buf + sizeof l, sizeof l); + iowrite32(le32_to_cpu(l), device + offset + sizeof l); + break; + default: + BUG(); + } +} + +static u32 vp_generation(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + return vp_modern_generation(&vp_dev->mdev); +} + +/* config->{get,set}_status() implementations */ +static u8 vp_get_status(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + return vp_modern_get_status(&vp_dev->mdev); +} + +static void vp_set_status(struct virtio_device *vdev, u8 status) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + /* We should never be setting status to 0. */ + BUG_ON(status == 0); + vp_modern_set_status(&vp_dev->mdev, status); +} + +static void vp_reset(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + + /* 0 status means a reset. */ + vp_modern_set_status(mdev, 0); + /* After writing 0 to device_status, the driver MUST wait for a read of + * device_status to return 0 before reinitializing the device. + * This will flush out the status write, and flush in device writes, + * including MSI-X interrupts, if any. + */ + while (vp_modern_get_status(mdev)) + msleep(1); + /* Flush pending VQ/configuration callbacks. */ + vp_synchronize_vectors(vdev); +} + +static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + unsigned long index; + + index = vq->index; + + /* activate the queue */ + vp_modern_set_queue_size(mdev, index, virtqueue_get_vring_size(vq)); + vp_modern_queue_address(mdev, index, virtqueue_get_desc_addr(vq), + virtqueue_get_avail_addr(vq), + virtqueue_get_used_addr(vq)); + + if (msix_vec != VIRTIO_MSI_NO_VECTOR) { + msix_vec = vp_modern_queue_vector(mdev, index, msix_vec); + if (msix_vec == VIRTIO_MSI_NO_VECTOR) + return -EBUSY; + } + + return 0; +} + +static int vp_modern_disable_vq_and_reset(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + unsigned long flags; + + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) + return -ENOENT; + + vp_modern_set_queue_reset(mdev, vq->index); + + info = vp_dev->vqs[vq->index]; + + /* delete vq from irq handler */ + spin_lock_irqsave(&vp_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vp_dev->lock, flags); + + INIT_LIST_HEAD(&info->node); + +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + __virtqueue_break(vq); +#endif + + /* For the case where vq has an exclusive irq, call synchronize_irq() to + * wait for completion. + * + * note: We can't use disable_irq() since it conflicts with the affinity + * managed IRQ that is used by some drivers. + */ + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) + synchronize_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); + + vq->reset = true; + + return 0; +} + +static int vp_modern_enable_vq_after_reset(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + unsigned long flags, index; + int err; + + if (!vq->reset) + return -EBUSY; + + index = vq->index; + info = vp_dev->vqs[index]; + + if (vp_modern_get_queue_reset(mdev, index)) + return -EBUSY; + + if (vp_modern_get_queue_enable(mdev, index)) + return -EBUSY; + + err = vp_active_vq(vq, info->msix_vector); + if (err) + return err; + + if (vq->callback) { + spin_lock_irqsave(&vp_dev->lock, flags); + list_add(&info->node, &vp_dev->virtqueues); + spin_unlock_irqrestore(&vp_dev->lock, flags); + } else { + INIT_LIST_HEAD(&info->node); + } + +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + __virtqueue_unbreak(vq); +#endif + + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); + vq->reset = false; + + return 0; +} + +static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) +{ + return vp_modern_config_vector(&vp_dev->mdev, vector); +} + +static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, + struct virtio_pci_vq_info *info, + unsigned int index, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec) +{ + + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtqueue *vq; + u16 num; + int err; + + if (index >= vp_modern_get_num_queues(mdev)) + return ERR_PTR(-EINVAL); + + /* Check if queue is either not available or already active. */ + num = vp_modern_get_queue_size(mdev, index); + if (!num || vp_modern_get_queue_enable(mdev, index)) + return ERR_PTR(-ENOENT); + + if (num & (num - 1)) { + dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num); + return ERR_PTR(-EINVAL); + } + + info->msix_vector = msix_vec; + + /* create the vring */ + vq = vring_create_virtqueue(index, num, + SMP_CACHE_BYTES, &vp_dev->vdev, + true, true, ctx, + vp_notify, callback, name); + if (!vq) + return ERR_PTR(-ENOMEM); + + vq->num_max = num; + + err = vp_active_vq(vq, msix_vec); + if (err) + goto err; + + vq->priv = (void __force *)vp_modern_map_vq_notify(mdev, index, NULL); + if (!vq->priv) { + err = -ENOMEM; + goto err; + } + + return vq; + +err: + vring_del_virtqueue(vq); + return ERR_PTR(err); +} + +static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], + vq_callback_t *callbacks[], + const char * const names[], const bool *ctx, + struct irq_affinity *desc) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtqueue *vq; + int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc); + + if (rc) + return rc; + + /* Select and activate all queues. Has to be done last: once we do + * this, there's no way to go back except reset. + */ + list_for_each_entry(vq, &vdev->vqs, list) + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); + + return 0; +} + +static void del_vq(struct virtio_pci_vq_info *info) +{ + struct virtqueue *vq = info->vq; + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + + if (vp_dev->msix_enabled) + vp_modern_queue_vector(mdev, vq->index, + VIRTIO_MSI_NO_VECTOR); + + if (!mdev->notify_base) + pci_iounmap(mdev->pci_dev, (void __force __iomem *)vq->priv); + + vring_del_virtqueue(vq); +} + +static int virtio_pci_find_shm_cap(struct pci_dev *dev, u8 required_id, + u8 *bar, u64 *offset, u64 *len) +{ + 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, cap_len, id, res_bar; + u32 tmp32; + u64 res_offset, res_length; + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + cfg_type), &type); + if (type != VIRTIO_PCI_CAP_SHARED_MEMORY_CFG) + continue; + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + cap_len), &cap_len); + if (cap_len != sizeof(struct virtio_pci_cap64)) { + dev_err(&dev->dev, "%s: shm cap with bad size offset:" + " %d size: %d\n", __func__, pos, cap_len); + continue; + } + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + id), &id); + if (id != required_id) + continue; + + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + bar), &res_bar); + if (res_bar >= PCI_STD_NUM_BARS) + continue; + + /* Type and ID match, and the BAR value isn't reserved. + * Looks good. + */ + + /* Read the lower 32bit of length and offset */ + pci_read_config_dword(dev, pos + offsetof(struct virtio_pci_cap, + offset), &tmp32); + res_offset = tmp32; + pci_read_config_dword(dev, pos + offsetof(struct virtio_pci_cap, + length), &tmp32); + res_length = tmp32; + + /* and now the top half */ + pci_read_config_dword(dev, + pos + offsetof(struct virtio_pci_cap64, + offset_hi), &tmp32); + res_offset |= ((u64)tmp32) << 32; + pci_read_config_dword(dev, + pos + offsetof(struct virtio_pci_cap64, + length_hi), &tmp32); + res_length |= ((u64)tmp32) << 32; + + *bar = res_bar; + *offset = res_offset; + *len = res_length; + + return pos; + } + return 0; +} + +static bool vp_get_shm_region(struct virtio_device *vdev, + struct virtio_shm_region *region, u8 id) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct pci_dev *pci_dev = vp_dev->pci_dev; + u8 bar; + u64 offset, len; + phys_addr_t phys_addr; + size_t bar_len; + + if (!virtio_pci_find_shm_cap(pci_dev, id, &bar, &offset, &len)) + return false; + + phys_addr = pci_resource_start(pci_dev, bar); + bar_len = pci_resource_len(pci_dev, bar); + + if ((offset + len) < offset) { + dev_err(&pci_dev->dev, "%s: cap offset+len overflow detected\n", + __func__); + return false; + } + + if (offset + len > bar_len) { + dev_err(&pci_dev->dev, "%s: bar shorter than cap offset+len\n", + __func__); + return false; + } + + region->len = len; + region->addr = (u64) phys_addr + offset; + + return true; +} + +static const struct virtio_config_ops virtio_pci_config_nodev_ops = { + .get = NULL, + .set = NULL, + .generation = vp_generation, + .get_status = vp_get_status, + .set_status = vp_set_status, + .reset = vp_reset, + .find_vqs = vp_modern_find_vqs, + .del_vqs = vp_del_vqs, + .synchronize_cbs = vp_synchronize_vectors, + .get_features = vp_get_features, + .finalize_features = vp_finalize_features, + .bus_name = vp_bus_name, + .set_vq_affinity = vp_set_vq_affinity, + .get_vq_affinity = vp_get_vq_affinity, + .get_shm_region = vp_get_shm_region, + .disable_vq_and_reset = vp_modern_disable_vq_and_reset, + .enable_vq_after_reset = vp_modern_enable_vq_after_reset, +}; + +static const struct virtio_config_ops virtio_pci_config_ops = { + .get = vp_get, + .set = vp_set, + .generation = vp_generation, + .get_status = vp_get_status, + .set_status = vp_set_status, + .reset = vp_reset, + .find_vqs = vp_modern_find_vqs, + .del_vqs = vp_del_vqs, + .synchronize_cbs = vp_synchronize_vectors, + .get_features = vp_get_features, + .finalize_features = vp_finalize_features, + .bus_name = vp_bus_name, + .set_vq_affinity = vp_set_vq_affinity, + .get_vq_affinity = vp_get_vq_affinity, + .get_shm_region = vp_get_shm_region, + .disable_vq_and_reset = vp_modern_disable_vq_and_reset, + .enable_vq_after_reset = vp_modern_enable_vq_after_reset, +}; + +/* the PCI probing function */ +int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct pci_dev *pci_dev = vp_dev->pci_dev; + int err; + + mdev->pci_dev = pci_dev; + + err = vp_modern_probe(mdev); + if (err) + return err; + + if (mdev->device) + vp_dev->vdev.config = &virtio_pci_config_ops; + else + vp_dev->vdev.config = &virtio_pci_config_nodev_ops; + + vp_dev->config_vector = vp_config_vector; + vp_dev->setup_vq = setup_vq; + vp_dev->del_vq = del_vq; + vp_dev->isr = mdev->isr; + vp_dev->vdev.id = mdev->id; + + return 0; +} + +void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + + vp_modern_remove(mdev); +} -- cgit v1.2.3