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path: root/drivers/misc/mic/host/mic_virtio.c
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Diffstat (limited to 'drivers/misc/mic/host/mic_virtio.c')
-rw-r--r--drivers/misc/mic/host/mic_virtio.c700
1 files changed, 700 insertions, 0 deletions
diff --git a/drivers/misc/mic/host/mic_virtio.c b/drivers/misc/mic/host/mic_virtio.c
new file mode 100644
index 000000000000..5b8494bd1e00
--- /dev/null
+++ b/drivers/misc/mic/host/mic_virtio.c
@@ -0,0 +1,700 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2013 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 MIC Host driver.
+ *
+ */
+#include <linux/pci.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+
+#include <linux/mic_common.h>
+#include "../common/mic_dev.h"
+#include "mic_device.h"
+#include "mic_smpt.h"
+#include "mic_virtio.h"
+
+/*
+ * Initiates the copies across the PCIe bus from card memory to
+ * a user space buffer.
+ */
+static int mic_virtio_copy_to_user(struct mic_vdev *mvdev,
+ void __user *ubuf, size_t len, u64 addr)
+{
+ int err;
+ void __iomem *dbuf = mvdev->mdev->aper.va + addr;
+ /*
+ * We are copying from IO below an should ideally use something
+ * like copy_to_user_fromio(..) if it existed.
+ */
+ if (copy_to_user(ubuf, dbuf, len)) {
+ err = -EFAULT;
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ mvdev->in_bytes += len;
+ err = 0;
+err:
+ return err;
+}
+
+/*
+ * Initiates copies across the PCIe bus from a user space
+ * buffer to card memory.
+ */
+static int mic_virtio_copy_from_user(struct mic_vdev *mvdev,
+ void __user *ubuf, size_t len, u64 addr)
+{
+ int err;
+ void __iomem *dbuf = mvdev->mdev->aper.va + addr;
+ /*
+ * We are copying to IO below and should ideally use something
+ * like copy_from_user_toio(..) if it existed.
+ */
+ if (copy_from_user(dbuf, ubuf, len)) {
+ err = -EFAULT;
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ mvdev->out_bytes += len;
+ err = 0;
+err:
+ return err;
+}
+
+#define MIC_VRINGH_READ true
+
+/* The function to call to notify the card about added buffers */
+static void mic_notify(struct vringh *vrh)
+{
+ struct mic_vringh *mvrh = container_of(vrh, struct mic_vringh, vrh);
+ struct mic_vdev *mvdev = mvrh->mvdev;
+ s8 db = mvdev->dc->h2c_vdev_db;
+
+ if (db != -1)
+ mvdev->mdev->ops->send_intr(mvdev->mdev, db);
+}
+
+/* Determine the total number of bytes consumed in a VRINGH KIOV */
+static inline u32 mic_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 mic_vringh_copy(struct mic_vdev *mvdev, struct vringh_kiov *iov,
+ void __user *ubuf, size_t len, bool read, size_t *out_len)
+{
+ int ret = 0;
+ size_t partlen, tot_len = 0;
+
+ while (len && iov->i < iov->used) {
+ partlen = min(iov->iov[iov->i].iov_len, len);
+ if (read)
+ ret = mic_virtio_copy_to_user(mvdev,
+ ubuf, partlen,
+ (u64)iov->iov[iov->i].iov_base);
+ else
+ ret = mic_virtio_copy_from_user(mvdev,
+ ubuf, partlen,
+ (u64)iov->iov[iov->i].iov_base);
+ if (ret) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ break;
+ }
+ len -= partlen;
+ ubuf += partlen;
+ tot_len += partlen;
+ iov->consumed += partlen;
+ iov->iov[iov->i].iov_len -= partlen;
+ iov->iov[iov->i].iov_base += partlen;
+ if (!iov->iov[iov->i].iov_len) {
+ /* Fix up old iov element then increment. */
+ iov->iov[iov->i].iov_len = iov->consumed;
+ iov->iov[iov->i].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 _mic_virtio_copy(struct mic_vdev *mvdev,
+ struct mic_copy_desc *copy)
+{
+ int ret = 0, iovcnt = copy->iovcnt;
+ struct iovec iov;
+ struct iovec __user *u_iov = copy->iov;
+ void __user *ubuf = NULL;
+ struct mic_vringh *mvr = &mvdev->mvr[copy->vr_idx];
+ struct vringh_kiov *riov = &mvr->riov;
+ struct vringh_kiov *wiov = &mvr->wiov;
+ struct vringh *vrh = &mvr->vrh;
+ u16 *head = &mvr->head;
+ struct mic_vring *vr = &mvr->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(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ break;
+ }
+ len = iov.iov_len;
+ ubuf = iov.iov_base;
+ }
+ /* Issue all the read descriptors first */
+ ret = mic_vringh_copy(mvdev, riov, ubuf, len,
+ MIC_VRINGH_READ, &out_len);
+ if (ret) {
+ dev_err(mic_dev(mvdev), "%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 = mic_vringh_copy(mvdev, wiov, ubuf, len,
+ !MIC_VRINGH_READ, &out_len);
+ if (ret) {
+ dev_err(mic_dev(mvdev), "%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 += mic_vringh_iov_consumed(riov);
+ total += mic_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 mic_verify_copy_args(struct mic_vdev *mvdev,
+ struct mic_copy_desc *copy)
+{
+ if (copy->vr_idx >= mvdev->dd->num_vq) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, -EINVAL);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/* Copy a specified number of virtio descriptors in a chain */
+int mic_virtio_copy_desc(struct mic_vdev *mvdev,
+ struct mic_copy_desc *copy)
+{
+ int err;
+ struct mic_vringh *mvr = &mvdev->mvr[copy->vr_idx];
+
+ err = mic_verify_copy_args(mvdev, copy);
+ if (err)
+ return err;
+
+ mutex_lock(&mvr->vr_mutex);
+ if (!mic_vdevup(mvdev)) {
+ err = -ENODEV;
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto err;
+ }
+ err = _mic_virtio_copy(mvdev, copy);
+ if (err) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, err);
+ }
+err:
+ mutex_unlock(&mvr->vr_mutex);
+ return err;
+}
+
+static void mic_virtio_init_post(struct mic_vdev *mvdev)
+{
+ struct mic_vqconfig *vqconfig = mic_vq_config(mvdev->dd);
+ int i;
+
+ for (i = 0; i < mvdev->dd->num_vq; i++) {
+ if (!le64_to_cpu(vqconfig[i].used_address)) {
+ dev_warn(mic_dev(mvdev), "used_address zero??\n");
+ continue;
+ }
+ mvdev->mvr[i].vrh.vring.used =
+ mvdev->mdev->aper.va +
+ le64_to_cpu(vqconfig[i].used_address);
+ }
+
+ mvdev->dc->used_address_updated = 0;
+
+ dev_dbg(mic_dev(mvdev), "%s: device type %d LINKUP\n",
+ __func__, mvdev->virtio_id);
+}
+
+static inline void mic_virtio_device_reset(struct mic_vdev *mvdev)
+{
+ int i;
+
+ dev_dbg(mic_dev(mvdev), "%s: status %d device type %d RESET\n",
+ __func__, mvdev->dd->status, mvdev->virtio_id);
+
+ for (i = 0; i < mvdev->dd->num_vq; i++)
+ /*
+ * Avoid lockdep false positive. The + 1 is for the mic
+ * mutex which is held in the reset devices code path.
+ */
+ mutex_lock_nested(&mvdev->mvr[i].vr_mutex, i + 1);
+
+ /* 0 status means "reset" */
+ mvdev->dd->status = 0;
+ mvdev->dc->vdev_reset = 0;
+ mvdev->dc->host_ack = 1;
+
+ for (i = 0; i < mvdev->dd->num_vq; i++) {
+ struct vringh *vrh = &mvdev->mvr[i].vrh;
+ mvdev->mvr[i].vring.info->avail_idx = 0;
+ vrh->completed = 0;
+ vrh->last_avail_idx = 0;
+ vrh->last_used_idx = 0;
+ }
+
+ for (i = 0; i < mvdev->dd->num_vq; i++)
+ mutex_unlock(&mvdev->mvr[i].vr_mutex);
+}
+
+void mic_virtio_reset_devices(struct mic_device *mdev)
+{
+ struct list_head *pos, *tmp;
+ struct mic_vdev *mvdev;
+
+ dev_dbg(mdev->sdev->parent, "%s\n", __func__);
+
+ list_for_each_safe(pos, tmp, &mdev->vdev_list) {
+ mvdev = list_entry(pos, struct mic_vdev, list);
+ mic_virtio_device_reset(mvdev);
+ mvdev->poll_wake = 1;
+ wake_up(&mvdev->waitq);
+ }
+}
+
+void mic_bh_handler(struct work_struct *work)
+{
+ struct mic_vdev *mvdev = container_of(work, struct mic_vdev,
+ virtio_bh_work);
+
+ if (mvdev->dc->used_address_updated)
+ mic_virtio_init_post(mvdev);
+
+ if (mvdev->dc->vdev_reset)
+ mic_virtio_device_reset(mvdev);
+
+ mvdev->poll_wake = 1;
+ wake_up(&mvdev->waitq);
+}
+
+static irqreturn_t mic_virtio_intr_handler(int irq, void *data)
+{
+ struct mic_vdev *mvdev = data;
+ struct mic_device *mdev = mvdev->mdev;
+
+ mdev->ops->ack_interrupt(mdev);
+ schedule_work(&mvdev->virtio_bh_work);
+ return IRQ_HANDLED;
+}
+
+int mic_virtio_config_change(struct mic_vdev *mvdev,
+ void __user *argp)
+{
+ DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
+ int ret = 0, retry = 100, i;
+ struct mic_bootparam *bootparam = mvdev->mdev->dp;
+ s8 db = bootparam->h2c_config_db;
+
+ mutex_lock(&mvdev->mdev->mic_mutex);
+ for (i = 0; i < mvdev->dd->num_vq; i++)
+ mutex_lock_nested(&mvdev->mvr[i].vr_mutex, i + 1);
+
+ if (db == -1 || mvdev->dd->type == -1) {
+ ret = -EIO;
+ goto exit;
+ }
+
+ if (copy_from_user(mic_vq_configspace(mvdev->dd),
+ argp, mvdev->dd->config_len)) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, -EFAULT);
+ ret = -EFAULT;
+ goto exit;
+ }
+ mvdev->dc->config_change = MIC_VIRTIO_PARAM_CONFIG_CHANGED;
+ mvdev->mdev->ops->send_intr(mvdev->mdev, db);
+
+ for (i = retry; i--;) {
+ ret = wait_event_timeout(wake,
+ mvdev->dc->guest_ack, msecs_to_jiffies(100));
+ if (ret)
+ break;
+ }
+
+ dev_dbg(mic_dev(mvdev),
+ "%s %d retry: %d\n", __func__, __LINE__, retry);
+ mvdev->dc->config_change = 0;
+ mvdev->dc->guest_ack = 0;
+exit:
+ for (i = 0; i < mvdev->dd->num_vq; i++)
+ mutex_unlock(&mvdev->mvr[i].vr_mutex);
+ mutex_unlock(&mvdev->mdev->mic_mutex);
+ return ret;
+}
+
+static int mic_copy_dp_entry(struct mic_vdev *mvdev,
+ void __user *argp,
+ __u8 *type,
+ struct mic_device_desc **devpage)
+{
+ struct mic_device *mdev = mvdev->mdev;
+ struct mic_device_desc dd, *dd_config, *devp;
+ struct mic_vqconfig *vqconfig;
+ int ret = 0, i;
+ bool slot_found = false;
+
+ if (copy_from_user(&dd, argp, sizeof(dd))) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, -EFAULT);
+ return -EFAULT;
+ }
+
+ if (mic_aligned_desc_size(&dd) > MIC_MAX_DESC_BLK_SIZE ||
+ dd.num_vq > MIC_MAX_VRINGS) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, -EINVAL);
+ return -EINVAL;
+ }
+
+ dd_config = kmalloc(mic_desc_size(&dd), GFP_KERNEL);
+ if (dd_config == NULL) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, -ENOMEM);
+ return -ENOMEM;
+ }
+ if (copy_from_user(dd_config, argp, mic_desc_size(&dd))) {
+ ret = -EFAULT;
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto exit;
+ }
+
+ vqconfig = mic_vq_config(dd_config);
+ for (i = 0; i < dd.num_vq; i++) {
+ if (le16_to_cpu(vqconfig[i].num) > MIC_MAX_VRING_ENTRIES) {
+ ret = -EINVAL;
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto exit;
+ }
+ }
+
+ /* Find the first free device page entry */
+ for (i = mic_aligned_size(struct mic_bootparam);
+ i < MIC_DP_SIZE - mic_total_desc_size(dd_config);
+ i += mic_total_desc_size(devp)) {
+ devp = mdev->dp + i;
+ if (devp->type == 0 || devp->type == -1) {
+ slot_found = true;
+ break;
+ }
+ }
+ if (!slot_found) {
+ ret = -EINVAL;
+ dev_err(mic_dev(mvdev), "%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 = dd_config->type;
+ dd_config->type = 0;
+ memcpy(devp, dd_config, mic_desc_size(dd_config));
+
+ *devpage = devp;
+exit:
+ kfree(dd_config);
+ return ret;
+}
+
+static void mic_init_device_ctrl(struct mic_vdev *mvdev,
+ 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;
+ mvdev->dc = dc;
+}
+
+int mic_virtio_add_device(struct mic_vdev *mvdev,
+ void __user *argp)
+{
+ struct mic_device *mdev = mvdev->mdev;
+ struct mic_device_desc *dd = NULL;
+ struct mic_vqconfig *vqconfig;
+ int vr_size, i, j, ret;
+ u8 type = 0;
+ s8 db;
+ char irqname[10];
+ struct mic_bootparam *bootparam = mdev->dp;
+ u16 num;
+
+ mutex_lock(&mdev->mic_mutex);
+
+ ret = mic_copy_dp_entry(mvdev, argp, &type, &dd);
+ if (ret) {
+ mutex_unlock(&mdev->mic_mutex);
+ return ret;
+ }
+
+ mic_init_device_ctrl(mvdev, dd);
+
+ mvdev->dd = dd;
+ mvdev->virtio_id = type;
+ vqconfig = mic_vq_config(dd);
+ INIT_WORK(&mvdev->virtio_bh_work, mic_bh_handler);
+
+ for (i = 0; i < dd->num_vq; i++) {
+ struct mic_vringh *mvr = &mvdev->mvr[i];
+ struct mic_vring *vr = &mvdev->mvr[i].vring;
+ num = le16_to_cpu(vqconfig[i].num);
+ mutex_init(&mvr->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(mic_dev(mvdev), "%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 = MIC_MAGIC + mvdev->virtio_id + i;
+ vqconfig[i].address = mic_map_single(mdev,
+ vr->va, vr_size);
+ if (mic_map_error(vqconfig[i].address)) {
+ free_pages((unsigned long)vr->va, get_order(vr_size));
+ ret = -ENOMEM;
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto err;
+ }
+ vqconfig[i].address = cpu_to_le64(vqconfig[i].address);
+
+ vring_init(&vr->vr, num, vr->va, MIC_VIRTIO_RING_ALIGN);
+ ret = vringh_init_kern(&mvr->vrh,
+ *(u32 *)mic_vq_features(mvdev->dd), num, false,
+ vr->vr.desc, vr->vr.avail, vr->vr.used);
+ if (ret) {
+ dev_err(mic_dev(mvdev), "%s %d err %d\n",
+ __func__, __LINE__, ret);
+ goto err;
+ }
+ vringh_kiov_init(&mvr->riov, NULL, 0);
+ vringh_kiov_init(&mvr->wiov, NULL, 0);
+ mvr->head = USHRT_MAX;
+ mvr->mvdev = mvdev;
+ mvr->vrh.notify = mic_notify;
+ dev_dbg(mdev->sdev->parent,
+ "%s %d index %d va %p info %p vr_size 0x%x\n",
+ __func__, __LINE__, i, vr->va, vr->info, vr_size);
+ }
+
+ snprintf(irqname, sizeof(irqname), "mic%dvirtio%d", mdev->id,
+ mvdev->virtio_id);
+ mvdev->virtio_db = mic_next_db(mdev);
+ mvdev->virtio_cookie = mic_request_irq(mdev, mic_virtio_intr_handler,
+ irqname, mvdev, mvdev->virtio_db, MIC_INTR_DB);
+ if (IS_ERR(mvdev->virtio_cookie)) {
+ ret = PTR_ERR(mvdev->virtio_cookie);
+ dev_dbg(mdev->sdev->parent, "request irq failed\n");
+ goto err;
+ }
+
+ mvdev->dc->c2h_vdev_db = mvdev->virtio_db;
+
+ list_add_tail(&mvdev->list, &mdev->vdev_list);
+ /*
+ * 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;
+
+ dev_dbg(mdev->sdev->parent, "Added virtio device id %d\n", dd->type);
+
+ db = bootparam->h2c_config_db;
+ if (db != -1)
+ mdev->ops->send_intr(mdev, db);
+ mutex_unlock(&mdev->mic_mutex);
+ return 0;
+err:
+ vqconfig = mic_vq_config(dd);
+ for (j = 0; j < i; j++) {
+ struct mic_vringh *mvr = &mvdev->mvr[j];
+ mic_unmap_single(mdev, le64_to_cpu(vqconfig[j].address),
+ mvr->vring.len);
+ free_pages((unsigned long)mvr->vring.va,
+ get_order(mvr->vring.len));
+ }
+ mutex_unlock(&mdev->mic_mutex);
+ return ret;
+}
+
+void mic_virtio_del_device(struct mic_vdev *mvdev)
+{
+ struct list_head *pos, *tmp;
+ struct mic_vdev *tmp_mvdev;
+ struct mic_device *mdev = mvdev->mdev;
+ DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
+ int i, ret, retry = 100;
+ struct mic_vqconfig *vqconfig;
+ struct mic_bootparam *bootparam = mdev->dp;
+ s8 db;
+
+ mutex_lock(&mdev->mic_mutex);
+ db = bootparam->h2c_config_db;
+ if (db == -1)
+ goto skip_hot_remove;
+ dev_dbg(mdev->sdev->parent,
+ "Requesting hot remove id %d\n", mvdev->virtio_id);
+ mvdev->dc->config_change = MIC_VIRTIO_PARAM_DEV_REMOVE;
+ mdev->ops->send_intr(mdev, db);
+ for (i = retry; i--;) {
+ ret = wait_event_timeout(wake,
+ mvdev->dc->guest_ack, msecs_to_jiffies(100));
+ if (ret)
+ break;
+ }
+ dev_dbg(mdev->sdev->parent,
+ "Device id %d config_change %d guest_ack %d\n",
+ mvdev->virtio_id, mvdev->dc->config_change,
+ mvdev->dc->guest_ack);
+ mvdev->dc->config_change = 0;
+ mvdev->dc->guest_ack = 0;
+skip_hot_remove:
+ mic_free_irq(mdev, mvdev->virtio_cookie, mvdev);
+ flush_work(&mvdev->virtio_bh_work);
+ vqconfig = mic_vq_config(mvdev->dd);
+ for (i = 0; i < mvdev->dd->num_vq; i++) {
+ struct mic_vringh *mvr = &mvdev->mvr[i];
+ vringh_kiov_cleanup(&mvr->riov);
+ vringh_kiov_cleanup(&mvr->wiov);
+ mic_unmap_single(mdev, le64_to_cpu(vqconfig[i].address),
+ mvr->vring.len);
+ free_pages((unsigned long)mvr->vring.va,
+ get_order(mvr->vring.len));
+ }
+
+ list_for_each_safe(pos, tmp, &mdev->vdev_list) {
+ tmp_mvdev = list_entry(pos, struct mic_vdev, list);
+ if (tmp_mvdev == mvdev) {
+ list_del(pos);
+ dev_dbg(mdev->sdev->parent,
+ "Removing virtio device id %d\n",
+ mvdev->virtio_id);
+ break;
+ }
+ }
+ /*
+ * 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();
+ mvdev->dd->type = -1;
+ mutex_unlock(&mdev->mic_mutex);
+}