[deliverable/linux.git] / drivers / virtio / virtio_pci.c

/*
 * Virtio PCI driver
 *
 * 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
 *
 * Authors:
 *  Anthony Liguori  <aliguori@us.ibm.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 *
 */

#include <linux/module.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/virtio.h>
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/virtio_pci.h>
#include <linux/highmem.h>
#include <linux/spinlock.h>

MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
MODULE_DESCRIPTION("virtio-pci");
MODULE_LICENSE("GPL");
MODULE_VERSION("1");

/* Our device structure */
struct virtio_pci_device
{
	struct virtio_device vdev;
	struct pci_dev *pci_dev;

	/* the IO mapping for the PCI config space */
	void *ioaddr;

	/* a list of queues so we can dispatch IRQs */
	spinlock_t lock;
	struct list_head virtqueues;
};

struct virtio_pci_vq_info
{
	/* the actual virtqueue */
	struct virtqueue *vq;

	/* the number of entries in the queue */
	int num;

	/* the index of the queue */
	int queue_index;

	/* the virtual address of the ring queue */
	void *queue;

	/* the list node for the virtqueues list */
	struct list_head node;
};

/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
static struct pci_device_id virtio_pci_id_table[] = {
	{ 0x1af4, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
	{ 0 },
};

MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);

/* A PCI device has it's own struct device and so does a virtio device so
 * we create a place for the virtio devices to show up in sysfs.  I think it
 * would make more sense for virtio to not insist on having it's own device. */
static struct device virtio_pci_root = {
	.parent		= NULL,
	.bus_id		= "virtio-pci",
};

/* Unique numbering for devices under the kvm root */
static unsigned int dev_index;

/* Convert a generic virtio device to our structure */
static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
{
	return container_of(vdev, struct virtio_pci_device, vdev);
}

/* virtio config->feature() implementation */
static bool vp_feature(struct virtio_device *vdev, unsigned bit)
{
	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
	u32 mask;

	/* Since this function is supposed to have the side effect of
	 * enabling a queried feature, we simulate that by doing a read
	 * from the host feature bitmask and then writing to the guest
	 * feature bitmask */
	mask = ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
	if (mask & (1 << bit)) {
		mask |= (1 << bit);
		iowrite32(mask, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
	}

	return !!(mask & (1 << bit));
}

/* virtio config->get() implementation */
static void vp_get(struct virtio_device *vdev, unsigned offset,
		   void *buf, unsigned len)
{
	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
	void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
	u8 *ptr = buf;
	int i;

	for (i = 0; i < len; i++)
		ptr[i] = ioread8(ioaddr + i);
}

/* the config->set() implementation.  it's symmetric to the config->get()
 * implementation */
static void vp_set(struct virtio_device *vdev, unsigned offset,
		   const void *buf, unsigned len)
{
	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
	void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
	const u8 *ptr = buf;
	int i;

	for (i = 0; i < len; i++)
		iowrite8(ptr[i], ioaddr + i);
}

/* 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 ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
}

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);
	return iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
}

static void vp_reset(struct virtio_device *vdev)
{
	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
	/* 0 status means a reset. */
	return iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
}

/* the notify function used when creating a virt queue */
static void vp_notify(struct virtqueue *vq)
{
	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
	struct virtio_pci_vq_info *info = vq->priv;

	/* we write the queue's selector into the notification register to
	 * signal the other end */
	iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
}

/* A small wrapper to also acknowledge the interrupt when it's handled.
 * I really need an EIO hook for the vring so I can ack the interrupt once we
 * know that we'll be handling the IRQ but before we invoke the callback since
 * the callback may notify the host which results in the host attempting to
 * raise an interrupt that we would then mask once we acknowledged the
 * interrupt. */
static irqreturn_t vp_interrupt(int irq, void *opaque)
{
	struct virtio_pci_device *vp_dev = opaque;
	struct virtio_pci_vq_info *info;
	irqreturn_t ret = IRQ_NONE;
	u8 isr;

	/* reading the ISR has the effect of also clearing it so it's very
	 * important to save off the value. */
	isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);

	/* It's definitely not us if the ISR was not high */
	if (!isr)
		return IRQ_NONE;

	/* Configuration change?  Tell driver if it wants to know. */
	if (isr & VIRTIO_PCI_ISR_CONFIG) {
		struct virtio_driver *drv;
		drv = container_of(vp_dev->vdev.dev.driver,
				   struct virtio_driver, driver);

		if (drv->config_changed)
			drv->config_changed(&vp_dev->vdev);
	}

	spin_lock(&vp_dev->lock);
	list_for_each_entry(info, &vp_dev->virtqueues, node) {
		if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
			ret = IRQ_HANDLED;
	}
	spin_unlock(&vp_dev->lock);

	return ret;
}

/* the config->find_vq() implementation */
static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
				    void (*callback)(struct virtqueue *vq))
{
	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
	struct virtio_pci_vq_info *info;
	struct virtqueue *vq;
	u16 num;
	int err;

	/* Select the queue we're interested in */
	iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);

	/* Check if queue is either not available or already active. */
	num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
	if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
		return ERR_PTR(-ENOENT);

	/* allocate and fill out our structure the represents an active
	 * queue */
	info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL);
	if (!info)
		return ERR_PTR(-ENOMEM);

	info->queue_index = index;
	info->num = num;

	info->queue = kzalloc(PAGE_ALIGN(vring_size(num,PAGE_SIZE)), GFP_KERNEL);
	if (info->queue == NULL) {
		err = -ENOMEM;
		goto out_info;
	}

	/* activate the queue */
	iowrite32(virt_to_phys(info->queue) >> PAGE_SHIFT,
		  vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);

	/* create the vring */
	vq = vring_new_virtqueue(info->num, vdev, info->queue,
				 vp_notify, callback);
	if (!vq) {
		err = -ENOMEM;
		goto out_activate_queue;
	}

	vq->priv = info;
	info->vq = vq;

	spin_lock(&vp_dev->lock);
	list_add(&info->node, &vp_dev->virtqueues);
	spin_unlock(&vp_dev->lock);

	return vq;

out_activate_queue:
	iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
	kfree(info->queue);
out_info:
	kfree(info);
	return ERR_PTR(err);
}

/* the config->del_vq() implementation */
static void vp_del_vq(struct virtqueue *vq)
{
	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
	struct virtio_pci_vq_info *info = vq->priv;

	spin_lock(&vp_dev->lock);
	list_del(&info->node);
	spin_unlock(&vp_dev->lock);

	vring_del_virtqueue(vq);

	/* Select and deactivate the queue */
	iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
	iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);

	kfree(info->queue);
	kfree(info);
}

static struct virtio_config_ops virtio_pci_config_ops = {
	.feature	= vp_feature,
	.get		= vp_get,
	.set		= vp_set,
	.get_status	= vp_get_status,
	.set_status	= vp_set_status,
	.reset		= vp_reset,
	.find_vq	= vp_find_vq,
	.del_vq		= vp_del_vq,
};

/* the PCI probing function */
static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
				      const struct pci_device_id *id)
{
	struct virtio_pci_device *vp_dev;
	int err;

	/* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
	if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
		return -ENODEV;

	if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
		printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
		       VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
		return -ENODEV;
	}

	/* allocate our structure and fill it out */
	vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
	if (vp_dev == NULL)
		return -ENOMEM;

	snprintf(vp_dev->vdev.dev.bus_id, BUS_ID_SIZE, "virtio%d", dev_index);
	vp_dev->vdev.index = dev_index;
	dev_index++;

	vp_dev->vdev.dev.parent = &virtio_pci_root;
	vp_dev->vdev.config = &virtio_pci_config_ops;
	vp_dev->pci_dev = pci_dev;
	INIT_LIST_HEAD(&vp_dev->virtqueues);
	spin_lock_init(&vp_dev->lock);

	/* enable the device */
	err = pci_enable_device(pci_dev);
	if (err)
		goto out;

	err = pci_request_regions(pci_dev, "virtio-pci");
	if (err)
		goto out_enable_device;

	vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
	if (vp_dev->ioaddr == NULL)
		goto out_req_regions;

	pci_set_drvdata(pci_dev, vp_dev);

	/* we use the subsystem vendor/device id as the virtio vendor/device
	 * id.  this allows us to use the same PCI vendor/device id for all
	 * virtio devices and to identify the particular virtio driver by
	 * the subsytem ids */
	vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
	vp_dev->vdev.id.device = pci_dev->subsystem_device;

	/* register a handler for the queue with the PCI device's interrupt */
	err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
			  vp_dev->vdev.dev.bus_id, vp_dev);
	if (err)
		goto out_set_drvdata;

	/* finally register the virtio device */
	err = register_virtio_device(&vp_dev->vdev);
	if (err)
		goto out_req_irq;

	return 0;

out_req_irq:
	free_irq(pci_dev->irq, vp_dev);
out_set_drvdata:
	pci_set_drvdata(pci_dev, NULL);
	pci_iounmap(pci_dev, vp_dev->ioaddr);
out_req_regions:
	pci_release_regions(pci_dev);
out_enable_device:
	pci_disable_device(pci_dev);
out:
	kfree(vp_dev);
	return err;
}

static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
{
	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);

	free_irq(pci_dev->irq, vp_dev);
	pci_set_drvdata(pci_dev, NULL);
	pci_iounmap(pci_dev, vp_dev->ioaddr);
	pci_release_regions(pci_dev);
	pci_disable_device(pci_dev);
	kfree(vp_dev);
}

#ifdef CONFIG_PM
static int virtio_pci_suspend(struct pci_dev *pci_dev, pm_message_t state)
{
	pci_save_state(pci_dev);
	pci_set_power_state(pci_dev, PCI_D3hot);
	return 0;
}

static int virtio_pci_resume(struct pci_dev *pci_dev)
{
	pci_restore_state(pci_dev);
	pci_set_power_state(pci_dev, PCI_D0);
	return 0;
}
#endif

static struct pci_driver virtio_pci_driver = {
	.name		= "virtio-pci",
	.id_table	= virtio_pci_id_table,
	.probe		= virtio_pci_probe,
	.remove		= virtio_pci_remove,
#ifdef CONFIG_PM
	.suspend	= virtio_pci_suspend,
	.resume		= virtio_pci_resume,
#endif
};

static int __init virtio_pci_init(void)
{
	int err;

	err = device_register(&virtio_pci_root);
	if (err)
		return err;

	err = pci_register_driver(&virtio_pci_driver);
	if (err)
		device_unregister(&virtio_pci_root);

	return err;
}

module_init(virtio_pci_init);

static void __exit virtio_pci_exit(void)
{
	device_unregister(&virtio_pci_root);
	pci_unregister_driver(&virtio_pci_driver);
}

module_exit(virtio_pci_exit);
Commit	Line	Data
3343660d AL	1	/*
	2	* Virtio PCI driver
	3	*
	4	* This module allows virtio devices to be used over a virtual PCI device.
	5	* This can be used with QEMU based VMMs like KVM or Xen.
	6	*
	7	* Copyright IBM Corp. 2007
	8	*
	9	* Authors:
	10	* Anthony Liguori <aliguori@us.ibm.com>
	11	*
	12	* This work is licensed under the terms of the GNU GPL, version 2 or later.
	13	* See the COPYING file in the top-level directory.
	14	*
	15	*/
	16
	17	#include <linux/module.h>
	18	#include <linux/list.h>
	19	#include <linux/pci.h>
	20	#include <linux/interrupt.h>
	21	#include <linux/virtio.h>
	22	#include <linux/virtio_config.h>
	23	#include <linux/virtio_ring.h>
	24	#include <linux/virtio_pci.h>
	25	#include <linux/highmem.h>
	26	#include <linux/spinlock.h>
	27
	28	MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
	29	MODULE_DESCRIPTION("virtio-pci");
	30	MODULE_LICENSE("GPL");
	31	MODULE_VERSION("1");
	32
	33	/* Our device structure */
	34	struct virtio_pci_device
	35	{
	36	struct virtio_device vdev;
	37	struct pci_dev *pci_dev;
	38
	39	/* the IO mapping for the PCI config space */
	40	void *ioaddr;
	41
	42	/* a list of queues so we can dispatch IRQs */
	43	spinlock_t lock;
	44	struct list_head virtqueues;
	45	};
	46
	47	struct virtio_pci_vq_info
	48	{
	49	/* the actual virtqueue */
	50	struct virtqueue *vq;
	51
	52	/* the number of entries in the queue */
	53	int num;
	54
	55	/* the index of the queue */
	56	int queue_index;
	57
	58	/* the virtual address of the ring queue */
	59	void *queue;
	60
	61	/* the list node for the virtqueues list */
	62	struct list_head node;
	63	};
	64
65	/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
66	static struct pci_device_id virtio_pci_id_table[] = {
67	{ 0x1af4, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
68	{ 0 },
69	};
70
71	MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
72
73	/* A PCI device has it's own struct device and so does a virtio device so
74	* we create a place for the virtio devices to show up in sysfs. I think it
75	* would make more sense for virtio to not insist on having it's own device. */
76	static struct device virtio_pci_root = {
77	.parent = NULL,
78	.bus_id = "virtio-pci",
79	};
80
81	/* Unique numbering for devices under the kvm root */
82	static unsigned int dev_index;
83
84	/* Convert a generic virtio device to our structure */
85	static struct virtio_pci_device to_vp_device(struct virtio_device vdev)
86	{
87	return container_of(vdev, struct virtio_pci_device, vdev);
88	}
89
90	/* virtio config->feature() implementation */
91	static bool vp_feature(struct virtio_device *vdev, unsigned bit)
92	{
93	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
94	u32 mask;
95
96	/* Since this function is supposed to have the side effect of
97	* enabling a queried feature, we simulate that by doing a read
98	* from the host feature bitmask and then writing to the guest
99	* feature bitmask */
100	mask = ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
101	if (mask & (1 << bit)) {
102	mask \|= (1 << bit);
103	iowrite32(mask, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
104	}
105
106	return !!(mask & (1 << bit));
107	}
108
109	/* virtio config->get() implementation */
110	static void vp_get(struct virtio_device *vdev, unsigned offset,
111	void *buf, unsigned len)
112	{
113	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
114	void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
115	u8 *ptr = buf;
116	int i;
117
118	for (i = 0; i < len; i++)
119	ptr[i] = ioread8(ioaddr + i);
120	}
121
122	/* the config->set() implementation. it's symmetric to the config->get()
123	* implementation */
124	static void vp_set(struct virtio_device *vdev, unsigned offset,
125	const void *buf, unsigned len)
126	{
127	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
128	void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
129	const u8 *ptr = buf;
130	int i;
131
132	for (i = 0; i < len; i++)
133	iowrite8(ptr[i], ioaddr + i);
134	}
135
136	/* config->{get,set}_status() implementations */
137	static u8 vp_get_status(struct virtio_device *vdev)
138	{
139	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
140	return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
141	}
142
143	static void vp_set_status(struct virtio_device *vdev, u8 status)
144	{
145	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
146	/* We should never be setting status to 0. */
147	BUG_ON(status == 0);
148	return iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
149	}
150
151	static void vp_reset(struct virtio_device *vdev)
152	{
153	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
154	/* 0 status means a reset. */
155	return iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
156	}
157
158	/* the notify function used when creating a virt queue */
159	static void vp_notify(struct virtqueue *vq)
160	{
161	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
162	struct virtio_pci_vq_info *info = vq->priv;
163
164	/* we write the queue's selector into the notification register to
165	* signal the other end */
166	iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
167	}
168
169	/* A small wrapper to also acknowledge the interrupt when it's handled.
170	* I really need an EIO hook for the vring so I can ack the interrupt once we
171	* know that we'll be handling the IRQ but before we invoke the callback since
172	* the callback may notify the host which results in the host attempting to
173	* raise an interrupt that we would then mask once we acknowledged the
174	* interrupt. */
175	static irqreturn_t vp_interrupt(int irq, void *opaque)
176	{
177	struct virtio_pci_device *vp_dev = opaque;
178	struct virtio_pci_vq_info *info;
179	irqreturn_t ret = IRQ_NONE;
180	u8 isr;
181
182	/* reading the ISR has the effect of also clearing it so it's very
183	* important to save off the value. */
184	isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
185
186	/* It's definitely not us if the ISR was not high */
187	if (!isr)
188	return IRQ_NONE;
189
190	/* Configuration change? Tell driver if it wants to know. */
191	if (isr & VIRTIO_PCI_ISR_CONFIG) {
192	struct virtio_driver *drv;
193	drv = container_of(vp_dev->vdev.dev.driver,
194	struct virtio_driver, driver);
195
196	if (drv->config_changed)
197	drv->config_changed(&vp_dev->vdev);
198	}
199
200	spin_lock(&vp_dev->lock);
201	list_for_each_entry(info, &vp_dev->virtqueues, node) {
202	if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
203	ret = IRQ_HANDLED;
204	}
205	spin_unlock(&vp_dev->lock);
206
207	return ret;
208	}
209
210	/* the config->find_vq() implementation */
211	static struct virtqueue vp_find_vq(struct virtio_device vdev, unsigned index,
212	void (callback)(struct virtqueue vq))
213	{
214	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
215	struct virtio_pci_vq_info *info;
216	struct virtqueue *vq;
217	u16 num;
218	int err;
219
220	/* Select the queue we're interested in */
221	iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
222
223	/* Check if queue is either not available or already active. */
224	num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
225	if (!num \|\| ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
226	return ERR_PTR(-ENOENT);
227
228	/* allocate and fill out our structure the represents an active
229	* queue */
230	info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL);
231	if (!info)
232	return ERR_PTR(-ENOMEM);
233
234	info->queue_index = index;
235	info->num = num;
236
237	info->queue = kzalloc(PAGE_ALIGN(vring_size(num,PAGE_SIZE)), GFP_KERNEL);
238	if (info->queue == NULL) {
239	err = -ENOMEM;
240	goto out_info;
241	}
242
243	/* activate the queue */
244	iowrite32(virt_to_phys(info->queue) >> PAGE_SHIFT,
245	vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
246
247	/* create the vring */
248	vq = vring_new_virtqueue(info->num, vdev, info->queue,
249	vp_notify, callback);
250	if (!vq) {
251	err = -ENOMEM;
252	goto out_activate_queue;
253	}
254
255	vq->priv = info;
256	info->vq = vq;
257
258	spin_lock(&vp_dev->lock);
259	list_add(&info->node, &vp_dev->virtqueues);
260	spin_unlock(&vp_dev->lock);
261
262	return vq;
263
264	out_activate_queue:
265	iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
266	kfree(info->queue);
267	out_info:
268	kfree(info);
269	return ERR_PTR(err);
270	}
271
272	/* the config->del_vq() implementation */
273	static void vp_del_vq(struct virtqueue *vq)
274	{
275	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
276	struct virtio_pci_vq_info *info = vq->priv;
277
278	spin_lock(&vp_dev->lock);
279	list_del(&info->node);
280	spin_unlock(&vp_dev->lock);
281
282	vring_del_virtqueue(vq);
283
284	/* Select and deactivate the queue */
285	iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
286	iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
287
288	kfree(info->queue);
289	kfree(info);
290	}
291
292	static struct virtio_config_ops virtio_pci_config_ops = {
293	.feature = vp_feature,
294	.get = vp_get,
295	.set = vp_set,
296	.get_status = vp_get_status,
297	.set_status = vp_set_status,
298	.reset = vp_reset,
299	.find_vq = vp_find_vq,
300	.del_vq = vp_del_vq,
301	};
302
303	/* the PCI probing function */
304	static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
305	const struct pci_device_id *id)
306	{
307	struct virtio_pci_device *vp_dev;
308	int err;
309
310	/* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
311	if (pci_dev->device < 0x1000 \|\| pci_dev->device > 0x103f)
312	return -ENODEV;
313
55a7c066 AL	314	if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
	315	printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
	316	VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
	317	return -ENODEV;
	318	}
	319
3343660d AL	320	/* allocate our structure and fill it out */
	321	vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
	322	if (vp_dev == NULL)
	323	return -ENOMEM;
	324
	325	snprintf(vp_dev->vdev.dev.bus_id, BUS_ID_SIZE, "virtio%d", dev_index);
	326	vp_dev->vdev.index = dev_index;
	327	dev_index++;
	328
	329	vp_dev->vdev.dev.parent = &virtio_pci_root;
	330	vp_dev->vdev.config = &virtio_pci_config_ops;
	331	vp_dev->pci_dev = pci_dev;
	332	INIT_LIST_HEAD(&vp_dev->virtqueues);
	333	spin_lock_init(&vp_dev->lock);
	334
	335	/* enable the device */
	336	err = pci_enable_device(pci_dev);
	337	if (err)
	338	goto out;
	339
	340	err = pci_request_regions(pci_dev, "virtio-pci");
	341	if (err)
	342	goto out_enable_device;
	343
	344	vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
	345	if (vp_dev->ioaddr == NULL)
	346	goto out_req_regions;
	347
	348	pci_set_drvdata(pci_dev, vp_dev);
	349
	350	/* we use the subsystem vendor/device id as the virtio vendor/device
	351	* id. this allows us to use the same PCI vendor/device id for all
	352	* virtio devices and to identify the particular virtio driver by
	353	* the subsytem ids */
	354	vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
	355	vp_dev->vdev.id.device = pci_dev->subsystem_device;
	356
	357	/* register a handler for the queue with the PCI device's interrupt */
	358	err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
	359	vp_dev->vdev.dev.bus_id, vp_dev);
	360	if (err)
	361	goto out_set_drvdata;
	362
	363	/* finally register the virtio device */
	364	err = register_virtio_device(&vp_dev->vdev);
	365	if (err)
	366	goto out_req_irq;
	367
	368	return 0;
	369
	370	out_req_irq:
	371	free_irq(pci_dev->irq, vp_dev);
	372	out_set_drvdata:
	373	pci_set_drvdata(pci_dev, NULL);
	374	pci_iounmap(pci_dev, vp_dev->ioaddr);
	375	out_req_regions:
	376	pci_release_regions(pci_dev);
	377	out_enable_device:
	378	pci_disable_device(pci_dev);
	379	out:
	380	kfree(vp_dev);
	381	return err;
	382	}
	383
384	static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
385	{
386	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
387
388	free_irq(pci_dev->irq, vp_dev);
389	pci_set_drvdata(pci_dev, NULL);
390	pci_iounmap(pci_dev, vp_dev->ioaddr);
391	pci_release_regions(pci_dev);
392	pci_disable_device(pci_dev);
393	kfree(vp_dev);
394	}
395
396	#ifdef CONFIG_PM
397	static int virtio_pci_suspend(struct pci_dev *pci_dev, pm_message_t state)
398	{
399	pci_save_state(pci_dev);
400	pci_set_power_state(pci_dev, PCI_D3hot);
401	return 0;
402	}
403
404	static int virtio_pci_resume(struct pci_dev *pci_dev)
405	{
406	pci_restore_state(pci_dev);
407	pci_set_power_state(pci_dev, PCI_D0);
408	return 0;
409	}
410	#endif
411
412	static struct pci_driver virtio_pci_driver = {
413	.name = "virtio-pci",
414	.id_table = virtio_pci_id_table,
415	.probe = virtio_pci_probe,
416	.remove = virtio_pci_remove,
417	#ifdef CONFIG_PM
418	.suspend = virtio_pci_suspend,
419	.resume = virtio_pci_resume,
420	#endif
421	};
422
423	static int __init virtio_pci_init(void)
424	{
425	int err;
426
427	err = device_register(&virtio_pci_root);
428	if (err)
429	return err;
430
431	err = pci_register_driver(&virtio_pci_driver);
432	if (err)
433	device_unregister(&virtio_pci_root);
434
435	return err;
436	}
437
438	module_init(virtio_pci_init);
439
440	static void __exit virtio_pci_exit(void)
441	{
442	device_unregister(&virtio_pci_root);
443	pci_unregister_driver(&virtio_pci_driver);
444	}
445
446	module_exit(virtio_pci_exit);