--- /dev/null
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2016 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Intel Virtio Over PCIe (VOP) driver.
+ *
+ */
+#include <linux/sched.h>
+#include <linux/poll.h>
+#include <linux/dma-mapping.h>
+
+#include <linux/mic_common.h>
+#include "../common/mic_dev.h"
+
+#include <linux/mic_ioctl.h>
+#include "vop_main.h"
+
+/* Helper API to obtain the VOP PCIe device */
+static inline struct device *vop_dev(struct vop_vdev *vdev)
+{
+ return vdev->vpdev->dev.parent;
+}
+
+/* Helper API to check if a virtio device is initialized */
+static inline int vop_vdev_inited(struct vop_vdev *vdev)
+{
+ if (!vdev)
+ return -EINVAL;
+ /* Device has not been created yet */
+ if (!vdev->dd || !vdev->dd->type) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, -EINVAL);
+ return -EINVAL;
+ }
+ /* Device has been removed/deleted */
+ if (vdev->dd->type == -1) {
+ dev_dbg(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, -ENODEV);
+ return -ENODEV;
+ }
+ return 0;
+}
+
+static void _vop_notify(struct vringh *vrh)
+{
+ struct vop_vringh *vvrh = container_of(vrh, struct vop_vringh, vrh);
+ struct vop_vdev *vdev = vvrh->vdev;
+ struct vop_device *vpdev = vdev->vpdev;
+ s8 db = vdev->dc->h2c_vdev_db;
+
+ if (db != -1)
+ vpdev->hw_ops->send_intr(vpdev, db);
+}
+
+static void vop_virtio_init_post(struct vop_vdev *vdev)
+{
+ struct mic_vqconfig *vqconfig = mic_vq_config(vdev->dd);
+ struct vop_device *vpdev = vdev->vpdev;
+ int i, used_size;
+
+ for (i = 0; i < vdev->dd->num_vq; i++) {
+ used_size = PAGE_ALIGN(sizeof(u16) * 3 +
+ sizeof(struct vring_used_elem) *
+ le16_to_cpu(vqconfig->num));
+ if (!le64_to_cpu(vqconfig[i].used_address)) {
+ dev_warn(vop_dev(vdev), "used_address zero??\n");
+ continue;
+ }
+ vdev->vvr[i].vrh.vring.used =
+ (void __force *)vpdev->hw_ops->ioremap(
+ vpdev,
+ le64_to_cpu(vqconfig[i].used_address),
+ used_size);
+ }
+
+ vdev->dc->used_address_updated = 0;
+
+ dev_info(vop_dev(vdev), "%s: device type %d LINKUP\n",
+ __func__, vdev->virtio_id);
+}
+
+static inline void vop_virtio_device_reset(struct vop_vdev *vdev)
+{
+ int i;
+
+ dev_dbg(vop_dev(vdev), "%s: status %d device type %d RESET\n",
+ __func__, vdev->dd->status, vdev->virtio_id);
+
+ for (i = 0; i < vdev->dd->num_vq; i++)
+ /*
+ * Avoid lockdep false positive. The + 1 is for the vop
+ * mutex which is held in the reset devices code path.
+ */
+ mutex_lock_nested(&vdev->vvr[i].vr_mutex, i + 1);
+
+ /* 0 status means "reset" */
+ vdev->dd->status = 0;
+ vdev->dc->vdev_reset = 0;
+ vdev->dc->host_ack = 1;
+
+ for (i = 0; i < vdev->dd->num_vq; i++) {
+ struct vringh *vrh = &vdev->vvr[i].vrh;
+
+ vdev->vvr[i].vring.info->avail_idx = 0;
+ vrh->completed = 0;
+ vrh->last_avail_idx = 0;
+ vrh->last_used_idx = 0;
+ }
+
+ for (i = 0; i < vdev->dd->num_vq; i++)
+ mutex_unlock(&vdev->vvr[i].vr_mutex);
+}
+
+static void vop_virtio_reset_devices(struct vop_info *vi)
+{
+ struct list_head *pos, *tmp;
+ struct vop_vdev *vdev;
+
+ list_for_each_safe(pos, tmp, &vi->vdev_list) {
+ vdev = list_entry(pos, struct vop_vdev, list);
+ vop_virtio_device_reset(vdev);
+ vdev->poll_wake = 1;
+ wake_up(&vdev->waitq);
+ }
+}
+
+static void vop_bh_handler(struct work_struct *work)
+{
+ struct vop_vdev *vdev = container_of(work, struct vop_vdev,
+ virtio_bh_work);
+
+ if (vdev->dc->used_address_updated)
+ vop_virtio_init_post(vdev);
+
+ if (vdev->dc->vdev_reset)
+ vop_virtio_device_reset(vdev);
+
+ vdev->poll_wake = 1;
+ wake_up(&vdev->waitq);
+}
+
+static irqreturn_t _vop_virtio_intr_handler(int irq, void *data)
+{
+ struct vop_vdev *vdev = data;
+ struct vop_device *vpdev = vdev->vpdev;
+
+ vpdev->hw_ops->ack_interrupt(vpdev, vdev->virtio_db);
+ schedule_work(&vdev->virtio_bh_work);
+ return IRQ_HANDLED;
+}
+
+static int vop_virtio_config_change(struct vop_vdev *vdev, void *argp)
+{
+ DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
+ int ret = 0, retry, i;
+ struct vop_device *vpdev = vdev->vpdev;
+ struct vop_info *vi = dev_get_drvdata(&vpdev->dev);
+ struct mic_bootparam *bootparam = vpdev->hw_ops->get_dp(vpdev);
+ s8 db = bootparam->h2c_config_db;
+
+ mutex_lock(&vi->vop_mutex);
+ for (i = 0; i < vdev->dd->num_vq; i++)
+ mutex_lock_nested(&vdev->vvr[i].vr_mutex, i + 1);
+
+ if (db == -1 || vdev->dd->type == -1) {
+ ret = -EIO;
+ goto exit;
+ }
+
+ memcpy(mic_vq_configspace(vdev->dd), argp, vdev->dd->config_len);
+ vdev->dc->config_change = MIC_VIRTIO_PARAM_CONFIG_CHANGED;
+ vpdev->hw_ops->send_intr(vpdev, db);
+
+ for (retry = 100; retry--;) {
+ ret = wait_event_timeout(wake, vdev->dc->guest_ack,
+ msecs_to_jiffies(100));
+ if (ret)
+ break;
+ }
+
+ dev_dbg(vop_dev(vdev),
+ "%s %d retry: %d\n", __func__, __LINE__, retry);
+ vdev->dc->config_change = 0;
+ vdev->dc->guest_ack = 0;
+exit:
+ for (i = 0; i < vdev->dd->num_vq; i++)
+ mutex_unlock(&vdev->vvr[i].vr_mutex);
+ mutex_unlock(&vi->vop_mutex);
+ return ret;
+}
+
+static int vop_copy_dp_entry(struct vop_vdev *vdev,
+ struct mic_device_desc *argp, __u8 *type,
+ struct mic_device_desc **devpage)
+{
+ struct vop_device *vpdev = vdev->vpdev;
+ struct mic_device_desc *devp;
+ struct mic_vqconfig *vqconfig;
+ int ret = 0, i;
+ bool slot_found = false;
+
+ vqconfig = mic_vq_config(argp);
+ for (i = 0; i < argp->num_vq; i++) {
+ if (le16_to_cpu(vqconfig[i].num) > MIC_MAX_VRING_ENTRIES) {
+ ret = -EINVAL;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto exit;
+ }
+ }
+
+ /* Find the first free device page entry */
+ for (i = sizeof(struct mic_bootparam);
+ i < MIC_DP_SIZE - mic_total_desc_size(argp);
+ i += mic_total_desc_size(devp)) {
+ devp = vpdev->hw_ops->get_dp(vpdev) + i;
+ if (devp->type == 0 || devp->type == -1) {
+ slot_found = true;
+ break;
+ }
+ }
+ if (!slot_found) {
+ ret = -EINVAL;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto exit;
+ }
+ /*
+ * Save off the type before doing the memcpy. Type will be set in the
+ * end after completing all initialization for the new device.
+ */
+ *type = argp->type;
+ argp->type = 0;
+ memcpy(devp, argp, mic_desc_size(argp));
+
+ *devpage = devp;
+exit:
+ return ret;
+}
+
+static void vop_init_device_ctrl(struct vop_vdev *vdev,
+ struct mic_device_desc *devpage)
+{
+ struct mic_device_ctrl *dc;
+
+ dc = (void *)devpage + mic_aligned_desc_size(devpage);
+
+ dc->config_change = 0;
+ dc->guest_ack = 0;
+ dc->vdev_reset = 0;
+ dc->host_ack = 0;
+ dc->used_address_updated = 0;
+ dc->c2h_vdev_db = -1;
+ dc->h2c_vdev_db = -1;
+ vdev->dc = dc;
+}
+
+static int vop_virtio_add_device(struct vop_vdev *vdev,
+ struct mic_device_desc *argp)
+{
+ struct vop_info *vi = vdev->vi;
+ struct vop_device *vpdev = vi->vpdev;
+ struct mic_device_desc *dd = NULL;
+ struct mic_vqconfig *vqconfig;
+ int vr_size, i, j, ret;
+ u8 type = 0;
+ s8 db = -1;
+ char irqname[16];
+ struct mic_bootparam *bootparam;
+ u16 num;
+ dma_addr_t vr_addr;
+
+ bootparam = vpdev->hw_ops->get_dp(vpdev);
+ init_waitqueue_head(&vdev->waitq);
+ INIT_LIST_HEAD(&vdev->list);
+ vdev->vpdev = vpdev;
+
+ ret = vop_copy_dp_entry(vdev, argp, &type, &dd);
+ if (ret) {
+ kfree(vdev);
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ return ret;
+ }
+
+ vop_init_device_ctrl(vdev, dd);
+
+ vdev->dd = dd;
+ vdev->virtio_id = type;
+ vqconfig = mic_vq_config(dd);
+ INIT_WORK(&vdev->virtio_bh_work, vop_bh_handler);
+
+ for (i = 0; i < dd->num_vq; i++) {
+ struct vop_vringh *vvr = &vdev->vvr[i];
+ struct mic_vring *vr = &vdev->vvr[i].vring;
+
+ num = le16_to_cpu(vqconfig[i].num);
+ mutex_init(&vvr->vr_mutex);
+ vr_size = PAGE_ALIGN(vring_size(num, MIC_VIRTIO_RING_ALIGN) +
+ sizeof(struct _mic_vring_info));
+ vr->va = (void *)
+ __get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(vr_size));
+ if (!vr->va) {
+ ret = -ENOMEM;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto err;
+ }
+ vr->len = vr_size;
+ vr->info = vr->va + vring_size(num, MIC_VIRTIO_RING_ALIGN);
+ vr->info->magic = cpu_to_le32(MIC_MAGIC + vdev->virtio_id + i);
+ vr_addr = dma_map_single(&vpdev->dev, vr->va, vr_size,
+ DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(&vpdev->dev, vr_addr)) {
+ free_pages((unsigned long)vr->va, get_order(vr_size));
+ ret = -ENOMEM;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto err;
+ }
+ vqconfig[i].address = cpu_to_le64(vr_addr);
+
+ vring_init(&vr->vr, num, vr->va, MIC_VIRTIO_RING_ALIGN);
+ ret = vringh_init_kern(&vvr->vrh,
+ *(u32 *)mic_vq_features(vdev->dd),
+ num, false, vr->vr.desc, vr->vr.avail,
+ vr->vr.used);
+ if (ret) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto err;
+ }
+ vringh_kiov_init(&vvr->riov, NULL, 0);
+ vringh_kiov_init(&vvr->wiov, NULL, 0);
+ vvr->head = USHRT_MAX;
+ vvr->vdev = vdev;
+ vvr->vrh.notify = _vop_notify;
+ dev_dbg(&vpdev->dev,
+ "%s %d index %d va %p info %p vr_size 0x%x\n",
+ __func__, __LINE__, i, vr->va, vr->info, vr_size);
+ vvr->buf = (void *)__get_free_pages(GFP_KERNEL,
+ get_order(VOP_INT_DMA_BUF_SIZE));
+ vvr->buf_da = dma_map_single(&vpdev->dev,
+ vvr->buf, VOP_INT_DMA_BUF_SIZE,
+ DMA_BIDIRECTIONAL);
+ }
+
+ snprintf(irqname, sizeof(irqname), "vop%dvirtio%d", vpdev->index,
+ vdev->virtio_id);
+ vdev->virtio_db = vpdev->hw_ops->next_db(vpdev);
+ vdev->virtio_cookie = vpdev->hw_ops->request_irq(vpdev,
+ _vop_virtio_intr_handler, irqname, vdev,
+ vdev->virtio_db);
+ if (IS_ERR(vdev->virtio_cookie)) {
+ ret = PTR_ERR(vdev->virtio_cookie);
+ dev_dbg(&vpdev->dev, "request irq failed\n");
+ goto err;
+ }
+
+ vdev->dc->c2h_vdev_db = vdev->virtio_db;
+
+ /*
+ * Order the type update with previous stores. This write barrier
+ * is paired with the corresponding read barrier before the uncached
+ * system memory read of the type, on the card while scanning the
+ * device page.
+ */
+ smp_wmb();
+ dd->type = type;
+ argp->type = type;
+
+ if (bootparam) {
+ db = bootparam->h2c_config_db;
+ if (db != -1)
+ vpdev->hw_ops->send_intr(vpdev, db);
+ }
+ dev_dbg(&vpdev->dev, "Added virtio id %d db %d\n", dd->type, db);
+ return 0;
+err:
+ vqconfig = mic_vq_config(dd);
+ for (j = 0; j < i; j++) {
+ struct vop_vringh *vvr = &vdev->vvr[j];
+
+ dma_unmap_single(&vpdev->dev, le64_to_cpu(vqconfig[j].address),
+ vvr->vring.len, DMA_BIDIRECTIONAL);
+ free_pages((unsigned long)vvr->vring.va,
+ get_order(vvr->vring.len));
+ }
+ return ret;
+}
+
+static void vop_dev_remove(struct vop_info *pvi, struct mic_device_ctrl *devp,
+ struct vop_device *vpdev)
+{
+ struct mic_bootparam *bootparam = vpdev->hw_ops->get_dp(vpdev);
+ s8 db;
+ int ret, retry;
+ DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
+
+ devp->config_change = MIC_VIRTIO_PARAM_DEV_REMOVE;
+ db = bootparam->h2c_config_db;
+ if (db != -1)
+ vpdev->hw_ops->send_intr(vpdev, db);
+ else
+ goto done;
+ for (retry = 15; retry--;) {
+ ret = wait_event_timeout(wake, devp->guest_ack,
+ msecs_to_jiffies(1000));
+ if (ret)
+ break;
+ }
+done:
+ devp->config_change = 0;
+ devp->guest_ack = 0;
+}
+
+static void vop_virtio_del_device(struct vop_vdev *vdev)
+{
+ struct vop_info *vi = vdev->vi;
+ struct vop_device *vpdev = vdev->vpdev;
+ int i;
+ struct mic_vqconfig *vqconfig;
+ struct mic_bootparam *bootparam = vpdev->hw_ops->get_dp(vpdev);
+
+ if (!bootparam)
+ goto skip_hot_remove;
+ vop_dev_remove(vi, vdev->dc, vpdev);
+skip_hot_remove:
+ vpdev->hw_ops->free_irq(vpdev, vdev->virtio_cookie, vdev);
+ flush_work(&vdev->virtio_bh_work);
+ vqconfig = mic_vq_config(vdev->dd);
+ for (i = 0; i < vdev->dd->num_vq; i++) {
+ struct vop_vringh *vvr = &vdev->vvr[i];
+
+ dma_unmap_single(&vpdev->dev,
+ vvr->buf_da, VOP_INT_DMA_BUF_SIZE,
+ DMA_BIDIRECTIONAL);
+ free_pages((unsigned long)vvr->buf,
+ get_order(VOP_INT_DMA_BUF_SIZE));
+ vringh_kiov_cleanup(&vvr->riov);
+ vringh_kiov_cleanup(&vvr->wiov);
+ dma_unmap_single(&vpdev->dev, le64_to_cpu(vqconfig[i].address),
+ vvr->vring.len, DMA_BIDIRECTIONAL);
+ free_pages((unsigned long)vvr->vring.va,
+ get_order(vvr->vring.len));
+ }
+ /*
+ * Order the type update with previous stores. This write barrier
+ * is paired with the corresponding read barrier before the uncached
+ * system memory read of the type, on the card while scanning the
+ * device page.
+ */
+ smp_wmb();
+ vdev->dd->type = -1;
+}
+
+/*
+ * vop_sync_dma - Wrapper for synchronous DMAs.
+ *
+ * @dev - The address of the pointer to the device instance used
+ * for DMA registration.
+ * @dst - destination DMA address.
+ * @src - source DMA address.
+ * @len - size of the transfer.
+ *
+ * Return DMA_SUCCESS on success
+ */
+static int vop_sync_dma(struct vop_vdev *vdev, dma_addr_t dst, dma_addr_t src,
+ size_t len)
+{
+ int err = 0;
+ struct dma_device *ddev;
+ struct dma_async_tx_descriptor *tx;
+ struct vop_info *vi = dev_get_drvdata(&vdev->vpdev->dev);
+ struct dma_chan *vop_ch = vi->dma_ch;
+
+ if (!vop_ch) {
+ err = -EBUSY;
+ goto error;
+ }
+ ddev = vop_ch->device;
+ tx = ddev->device_prep_dma_memcpy(vop_ch, dst, src, len,
+ DMA_PREP_FENCE);
+ if (!tx) {
+ err = -ENOMEM;
+ goto error;
+ } else {
+ dma_cookie_t cookie;
+
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ err = -ENOMEM;
+ goto error;
+ }
+ dma_async_issue_pending(vop_ch);
+ err = dma_sync_wait(vop_ch, cookie);
+ }
+error:
+ if (err)
+ dev_err(&vi->vpdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ return err;
+}
+
+#define VOP_USE_DMA true
+
+/*
+ * Initiates the copies across the PCIe bus from card memory to a user
+ * space buffer. When transfers are done using DMA, source/destination
+ * addresses and transfer length must follow the alignment requirements of
+ * the MIC DMA engine.
+ */
+static int vop_virtio_copy_to_user(struct vop_vdev *vdev, void __user *ubuf,
+ size_t len, u64 daddr, size_t dlen,
+ int vr_idx)
+{
+ struct vop_device *vpdev = vdev->vpdev;
+ void __iomem *dbuf = vpdev->hw_ops->ioremap(vpdev, daddr, len);
+ struct vop_vringh *vvr = &vdev->vvr[vr_idx];
+ struct vop_info *vi = dev_get_drvdata(&vpdev->dev);
+ size_t dma_alignment = 1 << vi->dma_ch->device->copy_align;
+ bool x200 = is_dma_copy_aligned(vi->dma_ch->device, 1, 1, 1);
+ size_t dma_offset, partlen;
+ int err;
+
+ if (!VOP_USE_DMA) {
+ if (copy_to_user(ubuf, (void __force *)dbuf, len)) {
+ err = -EFAULT;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ vdev->in_bytes += len;
+ err = 0;
+ goto err;
+ }
+
+ dma_offset = daddr - round_down(daddr, dma_alignment);
+ daddr -= dma_offset;
+ len += dma_offset;
+ /*
+ * X100 uses DMA addresses as seen by the card so adding
+ * the aperture base is not required for DMA. However x200
+ * requires DMA addresses to be an offset into the bar so
+ * add the aperture base for x200.
+ */
+ if (x200)
+ daddr += vpdev->aper->pa;
+ while (len) {
+ partlen = min_t(size_t, len, VOP_INT_DMA_BUF_SIZE);
+ err = vop_sync_dma(vdev, vvr->buf_da, daddr,
+ ALIGN(partlen, dma_alignment));
+ if (err) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ if (copy_to_user(ubuf, vvr->buf + dma_offset,
+ partlen - dma_offset)) {
+ err = -EFAULT;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ daddr += partlen;
+ ubuf += partlen;
+ dbuf += partlen;
+ vdev->in_bytes_dma += partlen;
+ vdev->in_bytes += partlen;
+ len -= partlen;
+ dma_offset = 0;
+ }
+ err = 0;
+err:
+ vpdev->hw_ops->iounmap(vpdev, dbuf);
+ dev_dbg(vop_dev(vdev),
+ "%s: ubuf %p dbuf %p len 0x%lx vr_idx 0x%x\n",
+ __func__, ubuf, dbuf, len, vr_idx);
+ return err;
+}
+
+/*
+ * Initiates copies across the PCIe bus from a user space buffer to card
+ * memory. When transfers are done using DMA, source/destination addresses
+ * and transfer length must follow the alignment requirements of the MIC
+ * DMA engine.
+ */
+static int vop_virtio_copy_from_user(struct vop_vdev *vdev, void __user *ubuf,
+ size_t len, u64 daddr, size_t dlen,
+ int vr_idx)
+{
+ struct vop_device *vpdev = vdev->vpdev;
+ void __iomem *dbuf = vpdev->hw_ops->ioremap(vpdev, daddr, len);
+ struct vop_vringh *vvr = &vdev->vvr[vr_idx];
+ struct vop_info *vi = dev_get_drvdata(&vdev->vpdev->dev);
+ size_t dma_alignment = 1 << vi->dma_ch->device->copy_align;
+ bool x200 = is_dma_copy_aligned(vi->dma_ch->device, 1, 1, 1);
+ size_t partlen;
+ bool dma = VOP_USE_DMA;
+ int err = 0;
+
+ if (daddr & (dma_alignment - 1)) {
+ vdev->tx_dst_unaligned += len;
+ dma = false;
+ } else if (ALIGN(len, dma_alignment) > dlen) {
+ vdev->tx_len_unaligned += len;
+ dma = false;
+ }
+
+ if (!dma)
+ goto memcpy;
+
+ /*
+ * X100 uses DMA addresses as seen by the card so adding
+ * the aperture base is not required for DMA. However x200
+ * requires DMA addresses to be an offset into the bar so
+ * add the aperture base for x200.
+ */
+ if (x200)
+ daddr += vpdev->aper->pa;
+ while (len) {
+ partlen = min_t(size_t, len, VOP_INT_DMA_BUF_SIZE);
+
+ if (copy_from_user(vvr->buf, ubuf, partlen)) {
+ err = -EFAULT;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ err = vop_sync_dma(vdev, daddr, vvr->buf_da,
+ ALIGN(partlen, dma_alignment));
+ if (err) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ daddr += partlen;
+ ubuf += partlen;
+ dbuf += partlen;
+ vdev->out_bytes_dma += partlen;
+ vdev->out_bytes += partlen;
+ len -= partlen;
+ }
+memcpy:
+ /*
+ * We are copying to IO below and should ideally use something
+ * like copy_from_user_toio(..) if it existed.
+ */
+ if (copy_from_user((void __force *)dbuf, ubuf, len)) {
+ err = -EFAULT;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ vdev->out_bytes += len;
+ err = 0;
+err:
+ vpdev->hw_ops->iounmap(vpdev, dbuf);
+ dev_dbg(vop_dev(vdev),
+ "%s: ubuf %p dbuf %p len 0x%lx vr_idx 0x%x\n",
+ __func__, ubuf, dbuf, len, vr_idx);
+ return err;
+}
+
+#define MIC_VRINGH_READ true
+
+/* Determine the total number of bytes consumed in a VRINGH KIOV */
+static inline u32 vop_vringh_iov_consumed(struct vringh_kiov *iov)
+{
+ int i;
+ u32 total = iov->consumed;
+
+ for (i = 0; i < iov->i; i++)
+ total += iov->iov[i].iov_len;
+ return total;
+}
+
+/*
+ * Traverse the VRINGH KIOV and issue the APIs to trigger the copies.
+ * This API is heavily based on the vringh_iov_xfer(..) implementation
+ * in vringh.c. The reason we cannot reuse vringh_iov_pull_kern(..)
+ * and vringh_iov_push_kern(..) directly is because there is no
+ * way to override the VRINGH xfer(..) routines as of v3.10.
+ */
+static int vop_vringh_copy(struct vop_vdev *vdev, struct vringh_kiov *iov,
+ void __user *ubuf, size_t len, bool read, int vr_idx,
+ size_t *out_len)
+{
+ int ret = 0;
+ size_t partlen, tot_len = 0;
+
+ while (len && iov->i < iov->used) {
+ struct kvec *kiov = &iov->iov[iov->i];
+
+ partlen = min(kiov->iov_len, len);
+ if (read)
+ ret = vop_virtio_copy_to_user(vdev, ubuf, partlen,
+ (u64)kiov->iov_base,
+ kiov->iov_len,
+ vr_idx);
+ else
+ ret = vop_virtio_copy_from_user(vdev, ubuf, partlen,
+ (u64)kiov->iov_base,
+ kiov->iov_len,
+ vr_idx);
+ if (ret) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ break;
+ }
+ len -= partlen;
+ ubuf += partlen;
+ tot_len += partlen;
+ iov->consumed += partlen;
+ kiov->iov_len -= partlen;
+ kiov->iov_base += partlen;
+ if (!kiov->iov_len) {
+ /* Fix up old iov element then increment. */
+ kiov->iov_len = iov->consumed;
+ kiov->iov_base -= iov->consumed;
+
+ iov->consumed = 0;
+ iov->i++;
+ }
+ }
+ *out_len = tot_len;
+ return ret;
+}
+
+/*
+ * Use the standard VRINGH infrastructure in the kernel to fetch new
+ * descriptors, initiate the copies and update the used ring.
+ */
+static int _vop_virtio_copy(struct vop_vdev *vdev, struct mic_copy_desc *copy)
+{
+ int ret = 0;
+ u32 iovcnt = copy->iovcnt;
+ struct iovec iov;
+ struct iovec __user *u_iov = copy->iov;
+ void __user *ubuf = NULL;
+ struct vop_vringh *vvr = &vdev->vvr[copy->vr_idx];
+ struct vringh_kiov *riov = &vvr->riov;
+ struct vringh_kiov *wiov = &vvr->wiov;
+ struct vringh *vrh = &vvr->vrh;
+ u16 *head = &vvr->head;
+ struct mic_vring *vr = &vvr->vring;
+ size_t len = 0, out_len;
+
+ copy->out_len = 0;
+ /* Fetch a new IOVEC if all previous elements have been processed */
+ if (riov->i == riov->used && wiov->i == wiov->used) {
+ ret = vringh_getdesc_kern(vrh, riov, wiov,
+ head, GFP_KERNEL);
+ /* Check if there are available descriptors */
+ if (ret <= 0)
+ return ret;
+ }
+ while (iovcnt) {
+ if (!len) {
+ /* Copy over a new iovec from user space. */
+ ret = copy_from_user(&iov, u_iov, sizeof(*u_iov));
+ if (ret) {
+ ret = -EINVAL;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ break;
+ }
+ len = iov.iov_len;
+ ubuf = iov.iov_base;
+ }
+ /* Issue all the read descriptors first */
+ ret = vop_vringh_copy(vdev, riov, ubuf, len,
+ MIC_VRINGH_READ, copy->vr_idx, &out_len);
+ if (ret) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ break;
+ }
+ len -= out_len;
+ ubuf += out_len;
+ copy->out_len += out_len;
+ /* Issue the write descriptors next */
+ ret = vop_vringh_copy(vdev, wiov, ubuf, len,
+ !MIC_VRINGH_READ, copy->vr_idx, &out_len);
+ if (ret) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ break;
+ }
+ len -= out_len;
+ ubuf += out_len;
+ copy->out_len += out_len;
+ if (!len) {
+ /* One user space iovec is now completed */
+ iovcnt--;
+ u_iov++;
+ }
+ /* Exit loop if all elements in KIOVs have been processed. */
+ if (riov->i == riov->used && wiov->i == wiov->used)
+ break;
+ }
+ /*
+ * Update the used ring if a descriptor was available and some data was
+ * copied in/out and the user asked for a used ring update.
+ */
+ if (*head != USHRT_MAX && copy->out_len && copy->update_used) {
+ u32 total = 0;
+
+ /* Determine the total data consumed */
+ total += vop_vringh_iov_consumed(riov);
+ total += vop_vringh_iov_consumed(wiov);
+ vringh_complete_kern(vrh, *head, total);
+ *head = USHRT_MAX;
+ if (vringh_need_notify_kern(vrh) > 0)
+ vringh_notify(vrh);
+ vringh_kiov_cleanup(riov);
+ vringh_kiov_cleanup(wiov);
+ /* Update avail idx for user space */
+ vr->info->avail_idx = vrh->last_avail_idx;
+ }
+ return ret;
+}
+
+static inline int vop_verify_copy_args(struct vop_vdev *vdev,
+ struct mic_copy_desc *copy)
+{
+ if (!vdev || copy->vr_idx >= vdev->dd->num_vq)
+ return -EINVAL;
+ return 0;
+}
+
+/* Copy a specified number of virtio descriptors in a chain */
+static int vop_virtio_copy_desc(struct vop_vdev *vdev,
+ struct mic_copy_desc *copy)
+{
+ int err;
+ struct vop_vringh *vvr = &vdev->vvr[copy->vr_idx];
+
+ err = vop_verify_copy_args(vdev, copy);
+ if (err)
+ return err;
+
+ mutex_lock(&vvr->vr_mutex);
+ if (!vop_vdevup(vdev)) {
+ err = -ENODEV;
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ err = _vop_virtio_copy(vdev, copy);
+ if (err) {
+ dev_err(vop_dev(vdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ }
+err:
+ mutex_unlock(&vvr->vr_mutex);
+ return err;
+}
+
+static int vop_open(struct inode *inode, struct file *f)
+{
+ struct vop_vdev *vdev;
+ struct vop_info *vi = container_of(f->private_data,
+ struct vop_info, miscdev);
+
+ vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
+ if (!vdev)
+ return -ENOMEM;
+ vdev->vi = vi;
+ mutex_init(&vdev->vdev_mutex);
+ f->private_data = vdev;
+ init_completion(&vdev->destroy);
+ complete(&vdev->destroy);
+ return 0;
+}
+
+static int vop_release(struct inode *inode, struct file *f)
+{
+ struct vop_vdev *vdev = f->private_data, *vdev_tmp;
+ struct vop_info *vi = vdev->vi;
+ struct list_head *pos, *tmp;
+ bool found = false;
+
+ mutex_lock(&vdev->vdev_mutex);
+ if (vdev->deleted)
+ goto unlock;
+ mutex_lock(&vi->vop_mutex);
+ list_for_each_safe(pos, tmp, &vi->vdev_list) {
+ vdev_tmp = list_entry(pos, struct vop_vdev, list);
+ if (vdev == vdev_tmp) {
+ vop_virtio_del_device(vdev);
+ list_del(pos);
+ found = true;
+ break;
+ }
+ }
+ mutex_unlock(&vi->vop_mutex);
+unlock:
+ mutex_unlock(&vdev->vdev_mutex);
+ if (!found)
+ wait_for_completion(&vdev->destroy);
+ f->private_data = NULL;
+ kfree(vdev);
+ return 0;
+}
+
+static long vop_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+{
+ struct vop_vdev *vdev = f->private_data;
+ struct vop_info *vi = vdev->vi;
+ void __user *argp = (void __user *)arg;
+ int ret;
+
+ switch (cmd) {
+ case MIC_VIRTIO_ADD_DEVICE:
+ {
+ struct mic_device_desc dd, *dd_config;
+
+ if (copy_from_user(&dd, argp, sizeof(dd)))
+ return -EFAULT;
+
+ if (mic_aligned_desc_size(&dd) > MIC_MAX_DESC_BLK_SIZE ||
+ dd.num_vq > MIC_MAX_VRINGS)
+ return -EINVAL;
+
+ dd_config = kzalloc(mic_desc_size(&dd), GFP_KERNEL);
+ if (!dd_config)
+ return -ENOMEM;
+ if (copy_from_user(dd_config, argp, mic_desc_size(&dd))) {
+ ret = -EFAULT;
+ goto free_ret;
+ }
+ mutex_lock(&vdev->vdev_mutex);
+ mutex_lock(&vi->vop_mutex);
+ ret = vop_virtio_add_device(vdev, dd_config);
+ if (ret)
+ goto unlock_ret;
+ list_add_tail(&vdev->list, &vi->vdev_list);
+unlock_ret:
+ mutex_unlock(&vi->vop_mutex);
+ mutex_unlock(&vdev->vdev_mutex);
+free_ret:
+ kfree(dd_config);
+ return ret;
+ }
+ case MIC_VIRTIO_COPY_DESC:
+ {
+ struct mic_copy_desc copy;
+
+ mutex_lock(&vdev->vdev_mutex);
+ ret = vop_vdev_inited(vdev);
+ if (ret)
+ goto _unlock_ret;
+
+ if (copy_from_user(©, argp, sizeof(copy))) {
+ ret = -EFAULT;
+ goto _unlock_ret;
+ }
+
+ ret = vop_virtio_copy_desc(vdev, ©);
+ if (ret < 0)
+ goto _unlock_ret;
+ if (copy_to_user(
+ &((struct mic_copy_desc __user *)argp)->out_len,
+ ©.out_len, sizeof(copy.out_len)))
+ ret = -EFAULT;
+_unlock_ret:
+ mutex_unlock(&vdev->vdev_mutex);
+ return ret;
+ }
+ case MIC_VIRTIO_CONFIG_CHANGE:
+ {
+ void *buf;
+
+ mutex_lock(&vdev->vdev_mutex);
+ ret = vop_vdev_inited(vdev);
+ if (ret)
+ goto __unlock_ret;
+ buf = kzalloc(vdev->dd->config_len, GFP_KERNEL);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto __unlock_ret;
+ }
+ if (copy_from_user(buf, argp, vdev->dd->config_len)) {
+ ret = -EFAULT;
+ goto done;
+ }
+ ret = vop_virtio_config_change(vdev, buf);
+done:
+ kfree(buf);
+__unlock_ret:
+ mutex_unlock(&vdev->vdev_mutex);
+ return ret;
+ }
+ default:
+ return -ENOIOCTLCMD;
+ };
+ return 0;
+}
+
+/*
+ * We return POLLIN | POLLOUT from poll when new buffers are enqueued, and
+ * not when previously enqueued buffers may be available. This means that
+ * in the card->host (TX) path, when userspace is unblocked by poll it
+ * must drain all available descriptors or it can stall.
+ */
+static unsigned int vop_poll(struct file *f, poll_table *wait)
+{
+ struct vop_vdev *vdev = f->private_data;
+ int mask = 0;
+
+ mutex_lock(&vdev->vdev_mutex);
+ if (vop_vdev_inited(vdev)) {
+ mask = POLLERR;
+ goto done;
+ }
+ poll_wait(f, &vdev->waitq, wait);
+ if (vop_vdev_inited(vdev)) {
+ mask = POLLERR;
+ } else if (vdev->poll_wake) {
+ vdev->poll_wake = 0;
+ mask = POLLIN | POLLOUT;
+ }
+done:
+ mutex_unlock(&vdev->vdev_mutex);
+ return mask;
+}
+
+static inline int
+vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
+ unsigned long *size, unsigned long *pa)
+{
+ struct vop_device *vpdev = vdev->vpdev;
+ unsigned long start = MIC_DP_SIZE;
+ int i;
+
+ /*
+ * MMAP interface is as follows:
+ * offset region
+ * 0x0 virtio device_page
+ * 0x1000 first vring
+ * 0x1000 + size of 1st vring second vring
+ * ....
+ */
+ if (!offset) {
+ *pa = virt_to_phys(vpdev->hw_ops->get_dp(vpdev));
+ *size = MIC_DP_SIZE;
+ return 0;
+ }
+
+ for (i = 0; i < vdev->dd->num_vq; i++) {
+ struct vop_vringh *vvr = &vdev->vvr[i];
+
+ if (offset == start) {
+ *pa = virt_to_phys(vvr->vring.va);
+ *size = vvr->vring.len;
+ return 0;
+ }
+ start += vvr->vring.len;
+ }
+ return -1;
+}
+
+/*
+ * Maps the device page and virtio rings to user space for readonly access.
+ */
+static int vop_mmap(struct file *f, struct vm_area_struct *vma)
+{
+ struct vop_vdev *vdev = f->private_data;
+ unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+ unsigned long pa, size = vma->vm_end - vma->vm_start, size_rem = size;
+ int i, err;
+
+ err = vop_vdev_inited(vdev);
+ if (err)
+ goto ret;
+ if (vma->vm_flags & VM_WRITE) {
+ err = -EACCES;
+ goto ret;
+ }
+ while (size_rem) {
+ i = vop_query_offset(vdev, offset, &size, &pa);
+ if (i < 0) {
+ err = -EINVAL;
+ goto ret;
+ }
+ err = remap_pfn_range(vma, vma->vm_start + offset,
+ pa >> PAGE_SHIFT, size,
+ vma->vm_page_prot);
+ if (err)
+ goto ret;
+ size_rem -= size;
+ offset += size;
+ }
+ret:
+ return err;
+}
+
+static const struct file_operations vop_fops = {
+ .open = vop_open,
+ .release = vop_release,
+ .unlocked_ioctl = vop_ioctl,
+ .poll = vop_poll,
+ .mmap = vop_mmap,
+ .owner = THIS_MODULE,
+};
+
+int vop_host_init(struct vop_info *vi)
+{
+ int rc;
+ struct miscdevice *mdev;
+ struct vop_device *vpdev = vi->vpdev;
+
+ INIT_LIST_HEAD(&vi->vdev_list);
+ vi->dma_ch = vpdev->dma_ch;
+ mdev = &vi->miscdev;
+ mdev->minor = MISC_DYNAMIC_MINOR;
+ snprintf(vi->name, sizeof(vi->name), "vop_virtio%d", vpdev->index);
+ mdev->name = vi->name;
+ mdev->fops = &vop_fops;
+ mdev->parent = &vpdev->dev;
+
+ rc = misc_register(mdev);
+ if (rc)
+ dev_err(&vpdev->dev, "%s failed rc %d\n", __func__, rc);
+ return rc;
+}
+
+void vop_host_uninit(struct vop_info *vi)
+{
+ struct list_head *pos, *tmp;
+ struct vop_vdev *vdev;
+
+ mutex_lock(&vi->vop_mutex);
+ vop_virtio_reset_devices(vi);
+ list_for_each_safe(pos, tmp, &vi->vdev_list) {
+ vdev = list_entry(pos, struct vop_vdev, list);
+ list_del(pos);
+ reinit_completion(&vdev->destroy);
+ mutex_unlock(&vi->vop_mutex);
+ mutex_lock(&vdev->vdev_mutex);
+ vop_virtio_del_device(vdev);
+ vdev->deleted = true;
+ mutex_unlock(&vdev->vdev_mutex);
+ complete(&vdev->destroy);
+ mutex_lock(&vi->vop_mutex);
+ }
+ mutex_unlock(&vi->vop_mutex);
+ misc_deregister(&vi->miscdev);
+}
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