// 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  <aliguori@us.ibm.com>
 *  Rusty Russell <rusty@rustcorp.com.au>
 *  Michael S. Tsirkin <mst@redhat.com>
 */

#include <linux/delay.h>
#include <linux/virtio_pci_admin.h>
#define VIRTIO_PCI_NO_LEGACY
#define VIRTIO_RING_NO_LEGACY
#include "virtio_pci_common.h"

#define VIRTIO_AVQ_SGS_MAX      4

static void vp_get_features(struct virtio_device *vdev, u64 *features)
{
        struct virtio_pci_device *vp_dev = to_vp_device(vdev);

        vp_modern_get_extended_features(&vp_dev->mdev, features);
}

static int vp_avq_index(struct virtio_device *vdev, u16 *index, u16 *num)
{
        struct virtio_pci_device *vp_dev = to_vp_device(vdev);

        *num = 0;
        if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
                return 0;

        *num = vp_modern_avq_num(&vp_dev->mdev);
        if (!(*num))
                return -EINVAL;
        *index = vp_modern_avq_index(&vp_dev->mdev);
        return 0;
}

void vp_modern_avq_done(struct virtqueue *vq)
{
        struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
        struct virtio_pci_admin_vq *admin_vq = &vp_dev->admin_vq;
        unsigned int status_size = sizeof(struct virtio_admin_cmd_status);
        struct virtio_admin_cmd *cmd;
        unsigned long flags;
        unsigned int len;

        spin_lock_irqsave(&admin_vq->lock, flags);
        do {
                virtqueue_disable_cb(vq);
                while ((cmd = virtqueue_get_buf(vq, &len))) {
                        /* If the number of bytes written by the device is less
                         * than the size of struct virtio_admin_cmd_status, the
                         * remaining status bytes will remain zero-initialized,
                         * since the buffer was zeroed during allocation.
                         * In this case, set the size of command_specific_result
                         * to 0.
                         */
                        if (len < status_size)
                                cmd->result_sg_size = 0;
                        else
                                cmd->result_sg_size = len - status_size;
                        complete(&cmd->completion);
                }
        } while (!virtqueue_enable_cb(vq));
        spin_unlock_irqrestore(&admin_vq->lock, flags);
}

static int virtqueue_exec_admin_cmd(struct virtio_pci_admin_vq *admin_vq,
                                    u16 opcode,
                                    struct scatterlist **sgs,
                                    unsigned int out_num,
                                    unsigned int in_num,
                                    struct virtio_admin_cmd *cmd)
{
        struct virtqueue *vq;
        unsigned long flags;
        int ret;

        vq = admin_vq->info->vq;
        if (!vq)
                return -EIO;

        if (opcode != VIRTIO_ADMIN_CMD_LIST_QUERY &&
            opcode != VIRTIO_ADMIN_CMD_LIST_USE &&
            !((1ULL << opcode) & admin_vq->supported_cmds))
                return -EOPNOTSUPP;

        init_completion(&cmd->completion);

again:
        if (virtqueue_is_broken(vq))
                return -EIO;

        spin_lock_irqsave(&admin_vq->lock, flags);
        ret = virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_KERNEL);
        if (ret < 0) {
                if (ret == -ENOSPC) {
                        spin_unlock_irqrestore(&admin_vq->lock, flags);
                        cpu_relax();
                        goto again;
                }
                goto unlock_err;
        }
        if (!virtqueue_kick(vq))
                goto unlock_err;
        spin_unlock_irqrestore(&admin_vq->lock, flags);

        wait_for_completion(&cmd->completion);

        return cmd->ret;

unlock_err:
        spin_unlock_irqrestore(&admin_vq->lock, flags);
        return -EIO;
}

int vp_modern_admin_cmd_exec(struct virtio_device *vdev,
                             struct virtio_admin_cmd *cmd)
{
        struct scatterlist *sgs[VIRTIO_AVQ_SGS_MAX], hdr, stat;
        struct virtio_pci_device *vp_dev = to_vp_device(vdev);
        struct virtio_admin_cmd_status *va_status;
        unsigned int out_num = 0, in_num = 0;
        struct virtio_admin_cmd_hdr *va_hdr;
        u16 status;
        int ret;

        if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
                return -EOPNOTSUPP;

        va_status = kzalloc_obj(*va_status);
        if (!va_status)
                return -ENOMEM;

        va_hdr = kzalloc_obj(*va_hdr);
        if (!va_hdr) {
                ret = -ENOMEM;
                goto err_alloc;
        }

        va_hdr->opcode = cmd->opcode;
        va_hdr->group_type = cmd->group_type;
        va_hdr->group_member_id = cmd->group_member_id;

        /* Add header */
        sg_init_one(&hdr, va_hdr, sizeof(*va_hdr));
        sgs[out_num] = &hdr;
        out_num++;

        if (cmd->data_sg) {
                sgs[out_num] = cmd->data_sg;
                out_num++;
        }

        /* Add return status */
        sg_init_one(&stat, va_status, sizeof(*va_status));
        sgs[out_num + in_num] = &stat;
        in_num++;

        if (cmd->result_sg) {
                sgs[out_num + in_num] = cmd->result_sg;
                in_num++;
        }

        ret = virtqueue_exec_admin_cmd(&vp_dev->admin_vq,
                                       le16_to_cpu(cmd->opcode),
                                       sgs, out_num, in_num, cmd);
        if (ret) {
                dev_err(&vdev->dev,
                        "Failed to execute command on admin vq: %d\n.", ret);
                goto err_cmd_exec;
        }

        status = le16_to_cpu(va_status->status);
        if (status != VIRTIO_ADMIN_STATUS_OK) {
                dev_err(&vdev->dev,
                        "admin command error: status(%#x) qualifier(%#x)\n",
                        status, le16_to_cpu(va_status->status_qualifier));
                ret = -status;
        }

err_cmd_exec:
        kfree(va_hdr);
err_alloc:
        kfree(va_status);
        return ret;
}

static void virtio_pci_admin_cmd_list_init(struct virtio_device *virtio_dev)
{
        struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev);
        struct virtio_admin_cmd cmd = {};
        struct scatterlist result_sg;
        struct scatterlist data_sg;
        __le64 *data;
        int ret;

        data = kzalloc_obj(*data);
        if (!data)
                return;

        sg_init_one(&result_sg, data, sizeof(*data));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_QUERY);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
        cmd.result_sg = &result_sg;

        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (ret)
                goto end;

        *data &= cpu_to_le64(VIRTIO_ADMIN_CMD_BITMAP);
        sg_init_one(&data_sg, data, sizeof(*data));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_USE);
        cmd.data_sg = &data_sg;
        cmd.result_sg = NULL;

        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (ret)
                goto end;

        vp_dev->admin_vq.supported_cmds = le64_to_cpu(*data);
end:
        kfree(data);
}

static void
virtio_pci_admin_cmd_dev_parts_objects_enable(struct virtio_device *virtio_dev)
{
        struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev);
        struct virtio_admin_cmd_cap_get_data *get_data;
        struct virtio_admin_cmd_cap_set_data *set_data;
        struct virtio_dev_parts_cap *result;
        struct virtio_admin_cmd cmd = {};
        struct scatterlist result_sg;
        struct scatterlist data_sg;
        u8 resource_objects_limit;
        u16 set_data_size;
        int ret;

        get_data = kzalloc_obj(*get_data);
        if (!get_data)
                return;

        result = kzalloc_obj(*result);
        if (!result)
                goto end;

        get_data->id = cpu_to_le16(VIRTIO_DEV_PARTS_CAP);
        sg_init_one(&data_sg, get_data, sizeof(*get_data));
        sg_init_one(&result_sg, result, sizeof(*result));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEVICE_CAP_GET);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SELF);
        cmd.data_sg = &data_sg;
        cmd.result_sg = &result_sg;
        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (ret)
                goto err_get;

        set_data_size = sizeof(*set_data) + sizeof(*result);
        set_data = kzalloc(set_data_size, GFP_KERNEL);
        if (!set_data)
                goto err_get;

        set_data->id = cpu_to_le16(VIRTIO_DEV_PARTS_CAP);

        /* Set the limit to the minimum value between the GET and SET values
         * supported by the device. Since the obj_id for VIRTIO_DEV_PARTS_CAP
         * is a globally unique value per PF, there is no possibility of
         * overlap between GET and SET operations.
         */
        resource_objects_limit = min(result->get_parts_resource_objects_limit,
                                     result->set_parts_resource_objects_limit);
        result->get_parts_resource_objects_limit = resource_objects_limit;
        result->set_parts_resource_objects_limit = resource_objects_limit;
        memcpy(set_data->cap_specific_data, result, sizeof(*result));
        sg_init_one(&data_sg, set_data, set_data_size);
        cmd.data_sg = &data_sg;
        cmd.result_sg = NULL;
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DRIVER_CAP_SET);
        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (ret)
                goto err_set;

        /* Allocate IDR to manage the dev caps objects */
        ida_init(&vp_dev->admin_vq.dev_parts_ida);
        vp_dev->admin_vq.max_dev_parts_objects = resource_objects_limit;

err_set:
        kfree(set_data);
err_get:
        kfree(result);
end:
        kfree(get_data);
}

static void virtio_pci_admin_cmd_cap_init(struct virtio_device *virtio_dev)
{
        struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev);
        struct virtio_admin_cmd_query_cap_id_result *data;
        struct virtio_admin_cmd cmd = {};
        struct scatterlist result_sg;
        int ret;

        data = kzalloc_obj(*data);
        if (!data)
                return;

        sg_init_one(&result_sg, data, sizeof(*data));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_CAP_ID_LIST_QUERY);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SELF);
        cmd.result_sg = &result_sg;

        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (ret)
                goto end;

        /* Max number of caps fits into a single u64 */
        BUILD_BUG_ON(sizeof(data->supported_caps) > sizeof(u64));

        vp_dev->admin_vq.supported_caps = le64_to_cpu(data->supported_caps[0]);

        if (!(vp_dev->admin_vq.supported_caps & (1 << VIRTIO_DEV_PARTS_CAP)))
                goto end;

        virtio_pci_admin_cmd_dev_parts_objects_enable(virtio_dev);
end:
        kfree(data);
}

static void vp_modern_avq_activate(struct virtio_device *vdev)
{
        if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
                return;

        virtio_pci_admin_cmd_list_init(vdev);
        virtio_pci_admin_cmd_cap_init(vdev);
}

static void vp_modern_avq_cleanup(struct virtio_device *vdev)
{
        struct virtio_pci_device *vp_dev = to_vp_device(vdev);
        struct virtio_admin_cmd *cmd;
        struct virtqueue *vq;

        if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
                return;

        vq = vp_dev->admin_vq.info->vq;
        if (!vq)
                return;

        while ((cmd = virtqueue_detach_unused_buf(vq))) {
                cmd->ret = -EIO;
                complete(&cmd->completion);
        }
}

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);

        if (features & BIT_ULL(VIRTIO_F_ADMIN_VQ))
                __virtio_set_bit(vdev, VIRTIO_F_ADMIN_VQ);
}

static int __vp_check_common_size_one_feature(struct virtio_device *vdev, u32 fbit,
                                            u32 offset, const char *fname)
{
        struct virtio_pci_device *vp_dev = to_vp_device(vdev);

        if (!__virtio_test_bit(vdev, fbit))
                return 0;

        if (likely(vp_dev->mdev.common_len >= offset))
                return 0;

        dev_err(&vdev->dev,
                "virtio: common cfg size(%zu) does not match the feature %s\n",
                vp_dev->mdev.common_len, fname);

        return -EINVAL;
}

#define vp_check_common_size_one_feature(vdev, fbit, field) \
        __vp_check_common_size_one_feature(vdev, fbit, \
                offsetofend(struct virtio_pci_modern_common_cfg, field), #fbit)

static int vp_check_common_size(struct virtio_device *vdev)
{
        if (vp_check_common_size_one_feature(vdev, VIRTIO_F_NOTIF_CONFIG_DATA, queue_notify_data))
                return -EINVAL;

        if (vp_check_common_size_one_feature(vdev, VIRTIO_F_RING_RESET, queue_reset))
                return -EINVAL;

        if (vp_check_common_size_one_feature(vdev, VIRTIO_F_ADMIN_VQ, admin_queue_num))
                return -EINVAL;

        return 0;
}

/* 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;
        }

        if (vp_check_common_size(vdev))
                return -EINVAL;

        vp_modern_set_extended_features(&vp_dev->mdev, vdev->features_array);

        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);
        if (status & VIRTIO_CONFIG_S_DRIVER_OK)
                vp_modern_avq_activate(vdev);
}

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);

        vp_modern_avq_cleanup(vdev);

        /* 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 bool vp_notify_with_data(struct virtqueue *vq)
{
        u32 data = vring_notification_data(vq);

        iowrite32(data, (void __iomem *)vq->priv);

        return true;
}

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;
        bool (*notify)(struct virtqueue *vq);
        struct virtqueue *vq;
        bool is_avq;
        u16 num;
        int err;

        if (__virtio_test_bit(&vp_dev->vdev, VIRTIO_F_NOTIFICATION_DATA))
                notify = vp_notify_with_data;
        else
                notify = vp_notify;

        is_avq = vp_is_avq(&vp_dev->vdev, index);
        if (index >= vp_modern_get_num_queues(mdev) && !is_avq)
                return ERR_PTR(-EINVAL);

        num = vp_modern_get_queue_size(mdev, index);
        /* Check if queue is either not available or already active. */
        if (!num || vp_modern_get_queue_enable(mdev, index))
                return ERR_PTR(-ENOENT);

        info->msix_vector = msix_vec;

        /* create the vring */
        vq = vring_create_virtqueue(index, num,
                                    SMP_CACHE_BYTES, &vp_dev->vdev,
                                    true, true, ctx,
                                    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[],
                              struct virtqueue_info vqs_info[],
                              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, vqs_info, 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;
}

/*
 * virtio_pci_admin_has_dev_parts - Checks whether the device parts
 * functionality is supported
 * @pdev: VF pci_dev
 *
 * Returns true on success.
 */
bool virtio_pci_admin_has_dev_parts(struct pci_dev *pdev)
{
        struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
        struct virtio_pci_device *vp_dev;

        if (!virtio_dev)
                return false;

        if (!virtio_has_feature(virtio_dev, VIRTIO_F_ADMIN_VQ))
                return false;

        vp_dev = to_vp_device(virtio_dev);

        if (!((vp_dev->admin_vq.supported_cmds & VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP) ==
                VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP))
                return false;

        return vp_dev->admin_vq.max_dev_parts_objects;
}
EXPORT_SYMBOL_GPL(virtio_pci_admin_has_dev_parts);

/*
 * virtio_pci_admin_mode_set - Sets the mode of a member device
 * @pdev: VF pci_dev
 * @flags: device mode's flags
 *
 * Note: caller must serialize access for the given device.
 * Returns 0 on success, or negative on failure.
 */
int virtio_pci_admin_mode_set(struct pci_dev *pdev, u8 flags)
{
        struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
        struct virtio_admin_cmd_dev_mode_set_data *data;
        struct virtio_admin_cmd cmd = {};
        struct scatterlist data_sg;
        int vf_id;
        int ret;

        if (!virtio_dev)
                return -ENODEV;

        vf_id = pci_iov_vf_id(pdev);
        if (vf_id < 0)
                return vf_id;

        data = kzalloc_obj(*data);
        if (!data)
                return -ENOMEM;

        data->flags = flags;
        sg_init_one(&data_sg, data, sizeof(*data));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_MODE_SET);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
        cmd.group_member_id = cpu_to_le64(vf_id + 1);
        cmd.data_sg = &data_sg;
        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);

        kfree(data);
        return ret;
}
EXPORT_SYMBOL_GPL(virtio_pci_admin_mode_set);

/*
 * virtio_pci_admin_obj_create - Creates an object for a given type and operation,
 * following the max objects that can be created for that request.
 * @pdev: VF pci_dev
 * @obj_type: Object type
 * @operation_type: Operation type
 * @obj_id: Output unique object id
 *
 * Note: caller must serialize access for the given device.
 * Returns 0 on success, or negative on failure.
 */
int virtio_pci_admin_obj_create(struct pci_dev *pdev, u16 obj_type, u8 operation_type,
                                u32 *obj_id)
{
        struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
        u16 data_size = sizeof(struct virtio_admin_cmd_resource_obj_create_data);
        struct virtio_admin_cmd_resource_obj_create_data *obj_create_data;
        struct virtio_resource_obj_dev_parts obj_dev_parts = {};
        struct virtio_pci_admin_vq *avq;
        struct virtio_admin_cmd cmd = {};
        struct scatterlist data_sg;
        void *data;
        int id = -1;
        int vf_id;
        int ret;

        if (!virtio_dev)
                return -ENODEV;

        vf_id = pci_iov_vf_id(pdev);
        if (vf_id < 0)
                return vf_id;

        if (obj_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS)
                return -EOPNOTSUPP;

        if (operation_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS_TYPE_GET &&
            operation_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS_TYPE_SET)
                return -EINVAL;

        avq = &to_vp_device(virtio_dev)->admin_vq;
        if (!avq->max_dev_parts_objects)
                return -EOPNOTSUPP;

        id = ida_alloc_range(&avq->dev_parts_ida, 0,
                             avq->max_dev_parts_objects - 1, GFP_KERNEL);
        if (id < 0)
                return id;

        *obj_id = id;
        data_size += sizeof(obj_dev_parts);
        data = kzalloc(data_size, GFP_KERNEL);
        if (!data) {
                ret = -ENOMEM;
                goto end;
        }

        obj_create_data = data;
        obj_create_data->hdr.type = cpu_to_le16(obj_type);
        obj_create_data->hdr.id = cpu_to_le32(*obj_id);
        obj_dev_parts.type = operation_type;
        memcpy(obj_create_data->resource_obj_specific_data, &obj_dev_parts,
               sizeof(obj_dev_parts));
        sg_init_one(&data_sg, data, data_size);
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_CREATE);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
        cmd.group_member_id = cpu_to_le64(vf_id + 1);
        cmd.data_sg = &data_sg;
        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);

        kfree(data);
end:
        if (ret)
                ida_free(&avq->dev_parts_ida, id);

        return ret;
}
EXPORT_SYMBOL_GPL(virtio_pci_admin_obj_create);

/*
 * virtio_pci_admin_obj_destroy - Destroys an object of a given type and id
 * @pdev: VF pci_dev
 * @obj_type: Object type
 * @id: Object id
 *
 * Note: caller must serialize access for the given device.
 * Returns 0 on success, or negative on failure.
 */
int virtio_pci_admin_obj_destroy(struct pci_dev *pdev, u16 obj_type, u32 id)
{
        struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
        struct virtio_admin_cmd_resource_obj_cmd_hdr *data;
        struct virtio_pci_device *vp_dev;
        struct virtio_admin_cmd cmd = {};
        struct scatterlist data_sg;
        int vf_id;
        int ret;

        if (!virtio_dev)
                return -ENODEV;

        vf_id = pci_iov_vf_id(pdev);
        if (vf_id < 0)
                return vf_id;

        if (obj_type != VIRTIO_RESOURCE_OBJ_DEV_PARTS)
                return -EINVAL;

        data = kzalloc_obj(*data);
        if (!data)
                return -ENOMEM;

        data->type = cpu_to_le16(obj_type);
        data->id = cpu_to_le32(id);
        sg_init_one(&data_sg, data, sizeof(*data));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_DESTROY);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
        cmd.group_member_id = cpu_to_le64(vf_id + 1);
        cmd.data_sg = &data_sg;
        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (!ret) {
                vp_dev = to_vp_device(virtio_dev);
                ida_free(&vp_dev->admin_vq.dev_parts_ida, id);
        }

        kfree(data);
        return ret;
}
EXPORT_SYMBOL_GPL(virtio_pci_admin_obj_destroy);

/*
 * virtio_pci_admin_dev_parts_metadata_get - Gets the metadata of the device parts
 * identified by the below attributes.
 * @pdev: VF pci_dev
 * @obj_type: Object type
 * @id: Object id
 * @metadata_type: Metadata type
 * @out: Upon success holds the output for 'metadata type size'
 *
 * Note: caller must serialize access for the given device.
 * Returns 0 on success, or negative on failure.
 */
int virtio_pci_admin_dev_parts_metadata_get(struct pci_dev *pdev, u16 obj_type,
                                            u32 id, u8 metadata_type, u32 *out)
{
        struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
        struct virtio_admin_cmd_dev_parts_metadata_result *result;
        struct virtio_admin_cmd_dev_parts_metadata_data *data;
        struct scatterlist data_sg, result_sg;
        struct virtio_admin_cmd cmd = {};
        int vf_id;
        int ret;

        if (!virtio_dev)
                return -ENODEV;

        if (metadata_type != VIRTIO_ADMIN_CMD_DEV_PARTS_METADATA_TYPE_SIZE)
                return -EOPNOTSUPP;

        vf_id = pci_iov_vf_id(pdev);
        if (vf_id < 0)
                return vf_id;

        data = kzalloc_obj(*data);
        if (!data)
                return -ENOMEM;

        result = kzalloc_obj(*result);
        if (!result) {
                ret = -ENOMEM;
                goto end;
        }

        data->hdr.type = cpu_to_le16(obj_type);
        data->hdr.id = cpu_to_le32(id);
        data->type = metadata_type;
        sg_init_one(&data_sg, data, sizeof(*data));
        sg_init_one(&result_sg, result, sizeof(*result));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_PARTS_METADATA_GET);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
        cmd.group_member_id = cpu_to_le64(vf_id + 1);
        cmd.data_sg = &data_sg;
        cmd.result_sg = &result_sg;
        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (!ret)
                *out = le32_to_cpu(result->parts_size.size);

        kfree(result);
end:
        kfree(data);
        return ret;
}
EXPORT_SYMBOL_GPL(virtio_pci_admin_dev_parts_metadata_get);

/*
 * virtio_pci_admin_dev_parts_get - Gets the device parts identified by the below attributes.
 * @pdev: VF pci_dev
 * @obj_type: Object type
 * @id: Object id
 * @get_type: Get type
 * @res_sg: Upon success holds the output result data
 * @res_size: Upon success holds the output result size
 *
 * Note: caller must serialize access for the given device.
 * Returns 0 on success, or negative on failure.
 */
int virtio_pci_admin_dev_parts_get(struct pci_dev *pdev, u16 obj_type, u32 id,
                                   u8 get_type, struct scatterlist *res_sg,
                                   u32 *res_size)
{
        struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
        struct virtio_admin_cmd_dev_parts_get_data *data;
        struct scatterlist data_sg;
        struct virtio_admin_cmd cmd = {};
        int vf_id;
        int ret;

        if (!virtio_dev)
                return -ENODEV;

        if (get_type != VIRTIO_ADMIN_CMD_DEV_PARTS_GET_TYPE_ALL)
                return -EOPNOTSUPP;

        vf_id = pci_iov_vf_id(pdev);
        if (vf_id < 0)
                return vf_id;

        data = kzalloc_obj(*data);
        if (!data)
                return -ENOMEM;

        data->hdr.type = cpu_to_le16(obj_type);
        data->hdr.id = cpu_to_le32(id);
        data->type = get_type;
        sg_init_one(&data_sg, data, sizeof(*data));
        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_PARTS_GET);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
        cmd.group_member_id = cpu_to_le64(vf_id + 1);
        cmd.data_sg = &data_sg;
        cmd.result_sg = res_sg;
        ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
        if (!ret)
                *res_size = cmd.result_sg_size;

        kfree(data);
        return ret;
}
EXPORT_SYMBOL_GPL(virtio_pci_admin_dev_parts_get);

/*
 * virtio_pci_admin_dev_parts_set - Sets the device parts identified by the below attributes.
 * @pdev: VF pci_dev
 * @data_sg: The device parts data, its layout follows struct virtio_admin_cmd_dev_parts_set_data
 *
 * Note: caller must serialize access for the given device.
 * Returns 0 on success, or negative on failure.
 */
int virtio_pci_admin_dev_parts_set(struct pci_dev *pdev, struct scatterlist *data_sg)
{
        struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev);
        struct virtio_admin_cmd cmd = {};
        int vf_id;

        if (!virtio_dev)
                return -ENODEV;

        vf_id = pci_iov_vf_id(pdev);
        if (vf_id < 0)
                return vf_id;

        cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_DEV_PARTS_SET);
        cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
        cmd.group_member_id = cpu_to_le64(vf_id + 1);
        cmd.data_sg = data_sg;
        return vp_modern_admin_cmd_exec(virtio_dev, &cmd);
}
EXPORT_SYMBOL_GPL(virtio_pci_admin_dev_parts_set);

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_extended_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_extended_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->avq_index = vp_avq_index;
        vp_dev->isr = mdev->isr;
        vp_dev->vdev.id = mdev->id;

        spin_lock_init(&vp_dev->admin_vq.lock);
        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);
}