[PATCH char-misc-next 2/8] misc: mic: Remove MIC X100 card virtio functionality

[Sudeep Dutt]

This patch deletes the virtio functionality from the MIC X100 card
driver. A subsequent patch will re-enable this functionality by
consolidating the hardware independent logic in a new Virtio over PCIe
(VOP) driver.

Reviewed-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
Signed-off-by: Sudeep Dutt <sudeep.dutt@xxxxxxxxx>
---
 drivers/misc/mic/card/Makefile     |   1 -
 drivers/misc/mic/card/mic_virtio.h |  76 -----
 drivers/misc/mic/card/mic_device.c |   9 +-
 drivers/misc/mic/card/mic_virtio.c | 634 -------------------------------------
 4 files changed, 1 insertion(+), 719 deletions(-)
 delete mode 100644 drivers/misc/mic/card/mic_virtio.h
 delete mode 100644 drivers/misc/mic/card/mic_virtio.c

diff --git a/drivers/misc/mic/card/Makefile b/drivers/misc/mic/card/Makefile
index 69d58be..6e9675e 100644
--- a/drivers/misc/mic/card/Makefile
+++ b/drivers/misc/mic/card/Makefile
@@ -8,4 +8,3 @@ obj-$(CONFIG_INTEL_MIC_CARD) += mic_card.o
 mic_card-y += mic_x100.o
 mic_card-y += mic_device.o
 mic_card-y += mic_debugfs.o
-mic_card-y += mic_virtio.o
diff --git a/drivers/misc/mic/card/mic_virtio.h b/drivers/misc/mic/card/mic_virtio.h
deleted file mode 100644
index d0407ba..0000000
--- a/drivers/misc/mic/card/mic_virtio.h
+++ /dev/null
@@ -1,76 +0,0 @@
-/*
- * 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".
- *
- * Disclaimer: The codes contained in these modules may be specific to
- * the Intel Software Development Platform codenamed: Knights Ferry, and
- * the Intel product codenamed: Knights Corner, and are not backward
- * compatible with other Intel products. Additionally, Intel will NOT
- * support the codes or instruction set in future products.
- *
- * Intel MIC Card driver.
- *
- */
-#ifndef __MIC_CARD_VIRTIO_H
-#define __MIC_CARD_VIRTIO_H
-
-#include <linux/mic_common.h>
-#include "mic_device.h"
-
-/*
- * 64 bit I/O access
- */
-#ifndef ioread64
-#define ioread64 readq
-#endif
-#ifndef iowrite64
-#define iowrite64 writeq
-#endif
-
-static inline unsigned mic_desc_size(struct mic_device_desc __iomem *desc)
-{
-	return sizeof(*desc)
-		+ ioread8(&desc->num_vq) * sizeof(struct mic_vqconfig)
-		+ ioread8(&desc->feature_len) * 2
-		+ ioread8(&desc->config_len);
-}
-
-static inline struct mic_vqconfig __iomem *
-mic_vq_config(struct mic_device_desc __iomem *desc)
-{
-	return (struct mic_vqconfig __iomem *)(desc + 1);
-}
-
-static inline __u8 __iomem *
-mic_vq_features(struct mic_device_desc __iomem *desc)
-{
-	return (__u8 __iomem *)(mic_vq_config(desc) + ioread8(&desc->num_vq));
-}
-
-static inline __u8 __iomem *
-mic_vq_configspace(struct mic_device_desc __iomem *desc)
-{
-	return mic_vq_features(desc) + ioread8(&desc->feature_len) * 2;
-}
-static inline unsigned mic_total_desc_size(struct mic_device_desc __iomem *desc)
-{
-	return mic_aligned_desc_size(desc) + sizeof(struct mic_device_ctrl);
-}
-
-int mic_devices_init(struct mic_driver *mdrv);
-void mic_devices_uninit(struct mic_driver *mdrv);
-
-#endif
diff --git a/drivers/misc/mic/card/mic_device.c b/drivers/misc/mic/card/mic_device.c
index d0edaf7..ff03c63 100644
--- a/drivers/misc/mic/card/mic_device.c
+++ b/drivers/misc/mic/card/mic_device.c
@@ -34,7 +34,6 @@
 #include <linux/mic_common.h>
 #include "../common/mic_dev.h"
 #include "mic_device.h"
-#include "mic_virtio.h"
 
 static struct mic_driver *g_drv;
 
@@ -309,9 +308,6 @@ int __init mic_driver_init(struct mic_driver *mdrv)
 		rc = -ENODEV;
 		goto irq_uninit;
 	}
-	rc = mic_devices_init(mdrv);
-	if (rc)
-		goto dma_free;
 	bootparam = mdrv->dp;
 	node_id = ioread8(&bootparam->node_id);
 	mdrv->scdev = scif_register_device(mdrv->dev, MIC_SCIF_DEV,
@@ -321,13 +317,11 @@ int __init mic_driver_init(struct mic_driver *mdrv)
 					   mdrv->num_dma_ch, true);
 	if (IS_ERR(mdrv->scdev)) {
 		rc = PTR_ERR(mdrv->scdev);
-		goto device_uninit;
+		goto dma_free;
 	}
 	mic_create_card_debug_dir(mdrv);
 done:
 	return rc;
-device_uninit:
-	mic_devices_uninit(mdrv);
 dma_free:
 	mic_free_dma_chans(mdrv);
 irq_uninit:
@@ -348,7 +342,6 @@ void mic_driver_uninit(struct mic_driver *mdrv)
 {
 	mic_delete_card_debug_dir(mdrv);
 	scif_unregister_device(mdrv->scdev);
-	mic_devices_uninit(mdrv);
 	mic_free_dma_chans(mdrv);
 	mic_uninit_irq();
 	mic_dp_uninit();
diff --git a/drivers/misc/mic/card/mic_virtio.c b/drivers/misc/mic/card/mic_virtio.c
deleted file mode 100644
index f6ed57d..0000000
--- a/drivers/misc/mic/card/mic_virtio.c
+++ /dev/null
@@ -1,634 +0,0 @@
-/*
- * 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".
- *
- * Disclaimer: The codes contained in these modules may be specific to
- * the Intel Software Development Platform codenamed: Knights Ferry, and
- * the Intel product codenamed: Knights Corner, and are not backward
- * compatible with other Intel products. Additionally, Intel will NOT
- * support the codes or instruction set in future products.
- *
- * Adapted from:
- *
- * virtio for kvm on s390
- *
- * Copyright IBM Corp. 2008
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License (version 2 only)
- * as published by the Free Software Foundation.
- *
- *    Author(s): Christian Borntraeger <borntraeger@xxxxxxxxxx>
- *
- * Intel MIC Card driver.
- *
- */
-#include <linux/delay.h>
-#include <linux/slab.h>
-#include <linux/virtio_config.h>
-
-#include "../common/mic_dev.h"
-#include "mic_virtio.h"
-
-#define VIRTIO_SUBCODE_64 0x0D00
-
-#define MIC_MAX_VRINGS                4
-struct mic_vdev {
-	struct virtio_device vdev;
-	struct mic_device_desc __iomem *desc;
-	struct mic_device_ctrl __iomem *dc;
-	struct mic_device *mdev;
-	void __iomem *vr[MIC_MAX_VRINGS];
-	int used_size[MIC_MAX_VRINGS];
-	struct completion reset_done;
-	struct mic_irq *virtio_cookie;
-	int c2h_vdev_db;
-};
-
-static struct mic_irq *virtio_config_cookie;
-#define to_micvdev(vd) container_of(vd, struct mic_vdev, vdev)
-
-/* Helper API to obtain the parent of the virtio device */
-static inline struct device *mic_dev(struct mic_vdev *mvdev)
-{
-	return mvdev->vdev.dev.parent;
-}
-
-/* This gets the device's feature bits. */
-static u64 mic_get_features(struct virtio_device *vdev)
-{
-	unsigned int i, bits;
-	u32 features = 0;
-	struct mic_device_desc __iomem *desc = to_micvdev(vdev)->desc;
-	u8 __iomem *in_features = mic_vq_features(desc);
-	int feature_len = ioread8(&desc->feature_len);
-
-	bits = min_t(unsigned, feature_len, sizeof(features)) * 8;
-	for (i = 0; i < bits; i++)
-		if (ioread8(&in_features[i / 8]) & (BIT(i % 8)))
-			features |= BIT(i);
-
-	return features;
-}
-
-static int mic_finalize_features(struct virtio_device *vdev)
-{
-	unsigned int i, bits;
-	struct mic_device_desc __iomem *desc = to_micvdev(vdev)->desc;
-	u8 feature_len = ioread8(&desc->feature_len);
-	/* Second half of bitmap is features we accept. */
-	u8 __iomem *out_features =
-		mic_vq_features(desc) + feature_len;
-
-	/* Give virtio_ring a chance to accept features. */
-	vring_transport_features(vdev);
-
-	/* Make sure we don't have any features > 32 bits! */
-	BUG_ON((u32)vdev->features != vdev->features);
-
-	memset_io(out_features, 0, feature_len);
-	bits = min_t(unsigned, feature_len,
-		sizeof(vdev->features)) * 8;
-	for (i = 0; i < bits; i++) {
-		if (__virtio_test_bit(vdev, i))
-			iowrite8(ioread8(&out_features[i / 8]) | (1 << (i % 8)),
-				 &out_features[i / 8]);
-	}
-
-	return 0;
-}
-
-/*
- * Reading and writing elements in config space
- */
-static void mic_get(struct virtio_device *vdev, unsigned int offset,
-		   void *buf, unsigned len)
-{
-	struct mic_device_desc __iomem *desc = to_micvdev(vdev)->desc;
-
-	if (offset + len > ioread8(&desc->config_len))
-		return;
-	memcpy_fromio(buf, mic_vq_configspace(desc) + offset, len);
-}
-
-static void mic_set(struct virtio_device *vdev, unsigned int offset,
-		   const void *buf, unsigned len)
-{
-	struct mic_device_desc __iomem *desc = to_micvdev(vdev)->desc;
-
-	if (offset + len > ioread8(&desc->config_len))
-		return;
-	memcpy_toio(mic_vq_configspace(desc) + offset, buf, len);
-}
-
-/*
- * The operations to get and set the status word just access the status
- * field of the device descriptor. set_status also interrupts the host
- * to tell about status changes.
- */
-static u8 mic_get_status(struct virtio_device *vdev)
-{
-	return ioread8(&to_micvdev(vdev)->desc->status);
-}
-
-static void mic_set_status(struct virtio_device *vdev, u8 status)
-{
-	struct mic_vdev *mvdev = to_micvdev(vdev);
-	if (!status)
-		return;
-	iowrite8(status, &mvdev->desc->status);
-	mic_send_intr(mvdev->mdev, mvdev->c2h_vdev_db);
-}
-
-/* Inform host on a virtio device reset and wait for ack from host */
-static void mic_reset_inform_host(struct virtio_device *vdev)
-{
-	struct mic_vdev *mvdev = to_micvdev(vdev);
-	struct mic_device_ctrl __iomem *dc = mvdev->dc;
-	int retry;
-
-	iowrite8(0, &dc->host_ack);
-	iowrite8(1, &dc->vdev_reset);
-	mic_send_intr(mvdev->mdev, mvdev->c2h_vdev_db);
-
-	/* Wait till host completes all card accesses and acks the reset */
-	for (retry = 100; retry--;) {
-		if (ioread8(&dc->host_ack))
-			break;
-		msleep(100);
-	};
-
-	dev_dbg(mic_dev(mvdev), "%s: retry: %d\n", __func__, retry);
-
-	/* Reset status to 0 in case we timed out */
-	iowrite8(0, &mvdev->desc->status);
-}
-
-static void mic_reset(struct virtio_device *vdev)
-{
-	struct mic_vdev *mvdev = to_micvdev(vdev);
-
-	dev_dbg(mic_dev(mvdev), "%s: virtio id %d\n",
-		__func__, vdev->id.device);
-
-	mic_reset_inform_host(vdev);
-	complete_all(&mvdev->reset_done);
-}
-
-/*
- * The virtio_ring code calls this API when it wants to notify the Host.
- */
-static bool mic_notify(struct virtqueue *vq)
-{
-	struct mic_vdev *mvdev = vq->priv;
-
-	mic_send_intr(mvdev->mdev, mvdev->c2h_vdev_db);
-	return true;
-}
-
-static void mic_del_vq(struct virtqueue *vq, int n)
-{
-	struct mic_vdev *mvdev = to_micvdev(vq->vdev);
-	struct vring *vr = (struct vring *)(vq + 1);
-
-	free_pages((unsigned long) vr->used, get_order(mvdev->used_size[n]));
-	vring_del_virtqueue(vq);
-	mic_card_unmap(mvdev->mdev, mvdev->vr[n]);
-	mvdev->vr[n] = NULL;
-}
-
-static void mic_del_vqs(struct virtio_device *vdev)
-{
-	struct mic_vdev *mvdev = to_micvdev(vdev);
-	struct virtqueue *vq, *n;
-	int idx = 0;
-
-	dev_dbg(mic_dev(mvdev), "%s\n", __func__);
-
-	list_for_each_entry_safe(vq, n, &vdev->vqs, list)
-		mic_del_vq(vq, idx++);
-}
-
-/*
- * This routine will assign vring's allocated in host/io memory. Code in
- * virtio_ring.c however continues to access this io memory as if it were local
- * memory without io accessors.
- */
-static struct virtqueue *mic_find_vq(struct virtio_device *vdev,
-				     unsigned index,
-				     void (*callback)(struct virtqueue *vq),
-				     const char *name)
-{
-	struct mic_vdev *mvdev = to_micvdev(vdev);
-	struct mic_vqconfig __iomem *vqconfig;
-	struct mic_vqconfig config;
-	struct virtqueue *vq;
-	void __iomem *va;
-	struct _mic_vring_info __iomem *info;
-	void *used;
-	int vr_size, _vr_size, err, magic;
-	struct vring *vr;
-	u8 type = ioread8(&mvdev->desc->type);
-
-	if (index >= ioread8(&mvdev->desc->num_vq))
-		return ERR_PTR(-ENOENT);
-
-	if (!name)
-		return ERR_PTR(-ENOENT);
-
-	/* First assign the vring's allocated in host memory */
-	vqconfig = mic_vq_config(mvdev->desc) + index;
-	memcpy_fromio(&config, vqconfig, sizeof(config));
-	_vr_size = vring_size(le16_to_cpu(config.num), MIC_VIRTIO_RING_ALIGN);
-	vr_size = PAGE_ALIGN(_vr_size + sizeof(struct _mic_vring_info));
-	va = mic_card_map(mvdev->mdev, le64_to_cpu(config.address), vr_size);
-	if (!va)
-		return ERR_PTR(-ENOMEM);
-	mvdev->vr[index] = va;
-	memset_io(va, 0x0, _vr_size);
-	vq = vring_new_virtqueue(index, le16_to_cpu(config.num),
-				 MIC_VIRTIO_RING_ALIGN, vdev, false,
-				 (void __force *)va, mic_notify, callback,
-				 name);
-	if (!vq) {
-		err = -ENOMEM;
-		goto unmap;
-	}
-	info = va + _vr_size;
-	magic = ioread32(&info->magic);
-
-	if (WARN(magic != MIC_MAGIC + type + index, "magic mismatch")) {
-		err = -EIO;
-		goto unmap;
-	}
-
-	/* Allocate and reassign used ring now */
-	mvdev->used_size[index] = PAGE_ALIGN(sizeof(__u16) * 3 +
-					     sizeof(struct vring_used_elem) *
-					     le16_to_cpu(config.num));
-	used = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
-					get_order(mvdev->used_size[index]));
-	if (!used) {
-		err = -ENOMEM;
-		dev_err(mic_dev(mvdev), "%s %d err %d\n",
-			__func__, __LINE__, err);
-		goto del_vq;
-	}
-	iowrite64(virt_to_phys(used), &vqconfig->used_address);
-
-	/*
-	 * To reassign the used ring here we are directly accessing
-	 * struct vring_virtqueue which is a private data structure
-	 * in virtio_ring.c. At the minimum, a BUILD_BUG_ON() in
-	 * vring_new_virtqueue() would ensure that
-	 *  (&vq->vring == (struct vring *) (&vq->vq + 1));
-	 */
-	vr = (struct vring *)(vq + 1);
-	vr->used = used;
-
-	vq->priv = mvdev;
-	return vq;
-del_vq:
-	vring_del_virtqueue(vq);
-unmap:
-	mic_card_unmap(mvdev->mdev, mvdev->vr[index]);
-	return ERR_PTR(err);
-}
-
-static int mic_find_vqs(struct virtio_device *vdev, unsigned nvqs,
-			struct virtqueue *vqs[],
-			vq_callback_t *callbacks[],
-			const char * const names[])
-{
-	struct mic_vdev *mvdev = to_micvdev(vdev);
-	struct mic_device_ctrl __iomem *dc = mvdev->dc;
-	int i, err, retry;
-
-	/* We must have this many virtqueues. */
-	if (nvqs > ioread8(&mvdev->desc->num_vq))
-		return -ENOENT;
-
-	for (i = 0; i < nvqs; ++i) {
-		dev_dbg(mic_dev(mvdev), "%s: %d: %s\n",
-			__func__, i, names[i]);
-		vqs[i] = mic_find_vq(vdev, i, callbacks[i], names[i]);
-		if (IS_ERR(vqs[i])) {
-			err = PTR_ERR(vqs[i]);
-			goto error;
-		}
-	}
-
-	iowrite8(1, &dc->used_address_updated);
-	/*
-	 * Send an interrupt to the host to inform it that used
-	 * rings have been re-assigned.
-	 */
-	mic_send_intr(mvdev->mdev, mvdev->c2h_vdev_db);
-	for (retry = 100; retry--;) {
-		if (!ioread8(&dc->used_address_updated))
-			break;
-		msleep(100);
-	};
-
-	dev_dbg(mic_dev(mvdev), "%s: retry: %d\n", __func__, retry);
-	if (!retry) {
-		err = -ENODEV;
-		goto error;
-	}
-
-	return 0;
-error:
-	mic_del_vqs(vdev);
-	return err;
-}
-
-/*
- * The config ops structure as defined by virtio config
- */
-static struct virtio_config_ops mic_vq_config_ops = {
-	.get_features = mic_get_features,
-	.finalize_features = mic_finalize_features,
-	.get = mic_get,
-	.set = mic_set,
-	.get_status = mic_get_status,
-	.set_status = mic_set_status,
-	.reset = mic_reset,
-	.find_vqs = mic_find_vqs,
-	.del_vqs = mic_del_vqs,
-};
-
-static irqreturn_t
-mic_virtio_intr_handler(int irq, void *data)
-{
-	struct mic_vdev *mvdev = data;
-	struct virtqueue *vq;
-
-	mic_ack_interrupt(mvdev->mdev);
-	list_for_each_entry(vq, &mvdev->vdev.vqs, list)
-		vring_interrupt(0, vq);
-
-	return IRQ_HANDLED;
-}
-
-static void mic_virtio_release_dev(struct device *_d)
-{
-	/*
-	 * No need for a release method similar to virtio PCI.
-	 * Provide an empty one to avoid getting a warning from core.
-	 */
-}
-
-/*
- * adds a new device and register it with virtio
- * appropriate drivers are loaded by the device model
- */
-static int mic_add_device(struct mic_device_desc __iomem *d,
-	unsigned int offset, struct mic_driver *mdrv)
-{
-	struct mic_vdev *mvdev;
-	int ret;
-	int virtio_db;
-	u8 type = ioread8(&d->type);
-
-	mvdev = kzalloc(sizeof(*mvdev), GFP_KERNEL);
-	if (!mvdev) {
-		dev_err(mdrv->dev, "Cannot allocate mic dev %u type %u\n",
-			offset, type);
-		return -ENOMEM;
-	}
-
-	mvdev->mdev = &mdrv->mdev;
-	mvdev->vdev.dev.parent = mdrv->dev;
-	mvdev->vdev.dev.release = mic_virtio_release_dev;
-	mvdev->vdev.id.device = type;
-	mvdev->vdev.config = &mic_vq_config_ops;
-	mvdev->desc = d;
-	mvdev->dc = (void __iomem *)d + mic_aligned_desc_size(d);
-	init_completion(&mvdev->reset_done);
-
-	virtio_db = mic_next_card_db();
-	mvdev->virtio_cookie = mic_request_card_irq(mic_virtio_intr_handler,
-			NULL, "virtio intr", mvdev, virtio_db);
-	if (IS_ERR(mvdev->virtio_cookie)) {
-		ret = PTR_ERR(mvdev->virtio_cookie);
-		goto kfree;
-	}
-	iowrite8((u8)virtio_db, &mvdev->dc->h2c_vdev_db);
-	mvdev->c2h_vdev_db = ioread8(&mvdev->dc->c2h_vdev_db);
-
-	ret = register_virtio_device(&mvdev->vdev);
-	if (ret) {
-		dev_err(mic_dev(mvdev),
-			"Failed to register mic device %u type %u\n",
-			offset, type);
-		goto free_irq;
-	}
-	iowrite64((u64)mvdev, &mvdev->dc->vdev);
-	dev_dbg(mic_dev(mvdev), "%s: registered mic device %u type %u mvdev %p\n",
-		__func__, offset, type, mvdev);
-
-	return 0;
-
-free_irq:
-	mic_free_card_irq(mvdev->virtio_cookie, mvdev);
-kfree:
-	kfree(mvdev);
-	return ret;
-}
-
-/*
- * match for a mic device with a specific desc pointer
- */
-static int mic_match_desc(struct device *dev, void *data)
-{
-	struct virtio_device *vdev = dev_to_virtio(dev);
-	struct mic_vdev *mvdev = to_micvdev(vdev);
-
-	return mvdev->desc == (void __iomem *)data;
-}
-
-static void mic_handle_config_change(struct mic_device_desc __iomem *d,
-	unsigned int offset, struct mic_driver *mdrv)
-{
-	struct mic_device_ctrl __iomem *dc
-		= (void __iomem *)d + mic_aligned_desc_size(d);
-	struct mic_vdev *mvdev = (struct mic_vdev *)ioread64(&dc->vdev);
-
-	if (ioread8(&dc->config_change) != MIC_VIRTIO_PARAM_CONFIG_CHANGED)
-		return;
-
-	dev_dbg(mdrv->dev, "%s %d\n", __func__, __LINE__);
-	virtio_config_changed(&mvdev->vdev);
-	iowrite8(1, &dc->guest_ack);
-}
-
-/*
- * removes a virtio device if a hot remove event has been
- * requested by the host.
- */
-static int mic_remove_device(struct mic_device_desc __iomem *d,
-	unsigned int offset, struct mic_driver *mdrv)
-{
-	struct mic_device_ctrl __iomem *dc
-		= (void __iomem *)d + mic_aligned_desc_size(d);
-	struct mic_vdev *mvdev = (struct mic_vdev *)ioread64(&dc->vdev);
-	u8 status;
-	int ret = -1;
-
-	if (ioread8(&dc->config_change) == MIC_VIRTIO_PARAM_DEV_REMOVE) {
-		dev_dbg(mdrv->dev,
-			"%s %d config_change %d type %d mvdev %p\n",
-			__func__, __LINE__,
-			ioread8(&dc->config_change), ioread8(&d->type), mvdev);
-
-		status = ioread8(&d->status);
-		reinit_completion(&mvdev->reset_done);
-		unregister_virtio_device(&mvdev->vdev);
-		mic_free_card_irq(mvdev->virtio_cookie, mvdev);
-		if (status & VIRTIO_CONFIG_S_DRIVER_OK)
-			wait_for_completion(&mvdev->reset_done);
-		kfree(mvdev);
-		iowrite8(1, &dc->guest_ack);
-		dev_dbg(mdrv->dev, "%s %d guest_ack %d\n",
-			__func__, __LINE__, ioread8(&dc->guest_ack));
-		ret = 0;
-	}
-
-	return ret;
-}
-
-#define REMOVE_DEVICES true
-
-static void mic_scan_devices(struct mic_driver *mdrv, bool remove)
-{
-	s8 type;
-	unsigned int i;
-	struct mic_device_desc __iomem *d;
-	struct mic_device_ctrl __iomem *dc;
-	struct device *dev;
-	int ret;
-
-	for (i = sizeof(struct mic_bootparam); i < MIC_DP_SIZE;
-		i += mic_total_desc_size(d)) {
-		d = mdrv->dp + i;
-		dc = (void __iomem *)d + mic_aligned_desc_size(d);
-		/*
-		 * This read barrier is paired with the corresponding write
-		 * barrier on the host which is inserted before adding or
-		 * removing a virtio device descriptor, by updating the type.
-		 */
-		rmb();
-		type = ioread8(&d->type);
-
-		/* end of list */
-		if (type == 0)
-			break;
-
-		if (type == -1)
-			continue;
-
-		/* device already exists */
-		dev = device_find_child(mdrv->dev, (void __force *)d,
-					mic_match_desc);
-		if (dev) {
-			if (remove)
-				iowrite8(MIC_VIRTIO_PARAM_DEV_REMOVE,
-					 &dc->config_change);
-			put_device(dev);
-			mic_handle_config_change(d, i, mdrv);
-			ret = mic_remove_device(d, i, mdrv);
-			if (!ret && !remove)
-				iowrite8(-1, &d->type);
-			if (remove) {
-				iowrite8(0, &dc->config_change);
-				iowrite8(0, &dc->guest_ack);
-			}
-			continue;
-		}
-
-		/* new device */
-		dev_dbg(mdrv->dev, "%s %d Adding new virtio device %p\n",
-			__func__, __LINE__, d);
-		if (!remove)
-			mic_add_device(d, i, mdrv);
-	}
-}
-
-/*
- * mic_hotplug_device tries to find changes in the device page.
- */
-static void mic_hotplug_devices(struct work_struct *work)
-{
-	struct mic_driver *mdrv = container_of(work,
-		struct mic_driver, hotplug_work);
-
-	mic_scan_devices(mdrv, !REMOVE_DEVICES);
-}
-
-/*
- * Interrupt handler for hot plug/config changes etc.
- */
-static irqreturn_t
-mic_extint_handler(int irq, void *data)
-{
-	struct mic_driver *mdrv = (struct mic_driver *)data;
-
-	dev_dbg(mdrv->dev, "%s %d hotplug work\n",
-		__func__, __LINE__);
-	mic_ack_interrupt(&mdrv->mdev);
-	schedule_work(&mdrv->hotplug_work);
-	return IRQ_HANDLED;
-}
-
-/*
- * Init function for virtio
- */
-int mic_devices_init(struct mic_driver *mdrv)
-{
-	int rc;
-	struct mic_bootparam __iomem *bootparam;
-	int config_db;
-
-	INIT_WORK(&mdrv->hotplug_work, mic_hotplug_devices);
-	mic_scan_devices(mdrv, !REMOVE_DEVICES);
-
-	config_db = mic_next_card_db();
-	virtio_config_cookie = mic_request_card_irq(mic_extint_handler, NULL,
-						    "virtio_config_intr", mdrv,
-						    config_db);
-	if (IS_ERR(virtio_config_cookie)) {
-		rc = PTR_ERR(virtio_config_cookie);
-		goto exit;
-	}
-
-	bootparam = mdrv->dp;
-	iowrite8(config_db, &bootparam->h2c_config_db);
-	return 0;
-exit:
-	return rc;
-}
-
-/*
- * Uninit function for virtio
- */
-void mic_devices_uninit(struct mic_driver *mdrv)
-{
-	struct mic_bootparam __iomem *bootparam = mdrv->dp;
-	iowrite8(-1, &bootparam->h2c_config_db);
-	mic_free_card_irq(virtio_config_cookie, mdrv);
-	flush_work(&mdrv->hotplug_work);
-	mic_scan_devices(mdrv, REMOVE_DEVICES);
-}
-- 
1.8.2.1