[linux-2.6-block.git] / drivers / uio / uio_hv_generic.c

/*
 * uio_hv_generic - generic UIO driver for VMBus
 *
 * Copyright (c) 2013-2016 Brocade Communications Systems, Inc.
 * Copyright (c) 2016, Microsoft Corporation.
 *
 *
 * This work is licensed under the terms of the GNU GPL, version 2.
 *
 * Since the driver does not declare any device ids, you must allocate
 * id and bind the device to the driver yourself.  For example:
 *
 * Associate Network GUID with UIO device
 * # echo "f8615163-df3e-46c5-913f-f2d2f965ed0e" \
 *    > /sys/bus/vmbus/drivers/uio_hv_generic/new_id
 * Then rebind
 * # echo -n "ed963694-e847-4b2a-85af-bc9cfc11d6f3" \
 *    > /sys/bus/vmbus/drivers/hv_netvsc/unbind
 * # echo -n "ed963694-e847-4b2a-85af-bc9cfc11d6f3" \
 *    > /sys/bus/vmbus/drivers/uio_hv_generic/bind
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/uio_driver.h>
#include <linux/netdevice.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/hyperv.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>

#include "../hv/hyperv_vmbus.h"

#define DRIVER_VERSION	"0.02.0"
#define DRIVER_AUTHOR	"Stephen Hemminger <sthemmin at microsoft.com>"
#define DRIVER_DESC	"Generic UIO driver for VMBus devices"

#define HV_RING_SIZE	 512	/* pages */
#define SEND_BUFFER_SIZE (15 * 1024 * 1024)
#define RECV_BUFFER_SIZE (15 * 1024 * 1024)

/*
 * List of resources to be mapped to user space
 * can be extended up to MAX_UIO_MAPS(5) items
 */
enum hv_uio_map {
	TXRX_RING_MAP = 0,
	INT_PAGE_MAP,
	MON_PAGE_MAP,
	RECV_BUF_MAP,
	SEND_BUF_MAP
};

struct hv_uio_private_data {
	struct uio_info info;
	struct hv_device *device;

	void	*recv_buf;
	u32	recv_gpadl;
	char	recv_name[32];	/* "recv_4294967295" */

	void	*send_buf;
	u32	send_gpadl;
	char	send_name[32];
};

/*
 * This is the irqcontrol callback to be registered to uio_info.
 * It can be used to disable/enable interrupt from user space processes.
 *
 * @param info
 *  pointer to uio_info.
 * @param irq_state
 *  state value. 1 to enable interrupt, 0 to disable interrupt.
 */
static int
hv_uio_irqcontrol(struct uio_info *info, s32 irq_state)
{
	struct hv_uio_private_data *pdata = info->priv;
	struct hv_device *dev = pdata->device;

	dev->channel->inbound.ring_buffer->interrupt_mask = !irq_state;
	virt_mb();

	return 0;
}

/*
 * Callback from vmbus_event when something is in inbound ring.
 */
static void hv_uio_channel_cb(void *context)
{
	struct hv_uio_private_data *pdata = context;
	struct hv_device *dev = pdata->device;

	dev->channel->inbound.ring_buffer->interrupt_mask = 1;
	virt_mb();

	uio_event_notify(&pdata->info);
}

/*
 * Callback from vmbus_event when channel is rescinded.
 */
static void hv_uio_rescind(struct vmbus_channel *channel)
{
	struct hv_device *hv_dev = channel->primary_channel->device_obj;
	struct hv_uio_private_data *pdata = hv_get_drvdata(hv_dev);

	/*
	 * Turn off the interrupt file handle
	 * Next read for event will return -EIO
	 */
	pdata->info.irq = 0;

	/* Wake up reader */
	uio_event_notify(&pdata->info);
}

static void
hv_uio_cleanup(struct hv_device *dev, struct hv_uio_private_data *pdata)
{
	if (pdata->send_gpadl)
		vmbus_teardown_gpadl(dev->channel, pdata->send_gpadl);
	vfree(pdata->send_buf);

	if (pdata->recv_gpadl)
		vmbus_teardown_gpadl(dev->channel, pdata->recv_gpadl);
	vfree(pdata->recv_buf);
}

static int
hv_uio_probe(struct hv_device *dev,
	     const struct hv_vmbus_device_id *dev_id)
{
	struct hv_uio_private_data *pdata;
	int ret;

	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return -ENOMEM;

	ret = vmbus_open(dev->channel, HV_RING_SIZE * PAGE_SIZE,
			 HV_RING_SIZE * PAGE_SIZE, NULL, 0,
			 hv_uio_channel_cb, pdata);
	if (ret)
		goto fail;

	/* Communicating with host has to be via shared memory not hypercall */
	if (!dev->channel->offermsg.monitor_allocated) {
		dev_err(&dev->device, "vmbus channel requires hypercall\n");
		ret = -ENOTSUPP;
		goto fail_close;
	}

	dev->channel->inbound.ring_buffer->interrupt_mask = 1;
	set_channel_read_mode(dev->channel, HV_CALL_ISR);

	/* Fill general uio info */
	pdata->info.name = "uio_hv_generic";
	pdata->info.version = DRIVER_VERSION;
	pdata->info.irqcontrol = hv_uio_irqcontrol;
	pdata->info.irq = UIO_IRQ_CUSTOM;

	/* mem resources */
	pdata->info.mem[TXRX_RING_MAP].name = "txrx_rings";
	pdata->info.mem[TXRX_RING_MAP].addr
		= (uintptr_t)dev->channel->ringbuffer_pages;
	pdata->info.mem[TXRX_RING_MAP].size
		= dev->channel->ringbuffer_pagecount << PAGE_SHIFT;
	pdata->info.mem[TXRX_RING_MAP].memtype = UIO_MEM_LOGICAL;

	pdata->info.mem[INT_PAGE_MAP].name = "int_page";
	pdata->info.mem[INT_PAGE_MAP].addr
		= (uintptr_t)vmbus_connection.int_page;
	pdata->info.mem[INT_PAGE_MAP].size = PAGE_SIZE;
	pdata->info.mem[INT_PAGE_MAP].memtype = UIO_MEM_LOGICAL;

	pdata->info.mem[MON_PAGE_MAP].name = "monitor_page";
	pdata->info.mem[MON_PAGE_MAP].addr
		= (uintptr_t)vmbus_connection.monitor_pages[1];
	pdata->info.mem[MON_PAGE_MAP].size = PAGE_SIZE;
	pdata->info.mem[MON_PAGE_MAP].memtype = UIO_MEM_LOGICAL;

	pdata->recv_buf = vzalloc(RECV_BUFFER_SIZE);
	if (pdata->recv_buf == NULL) {
		ret = -ENOMEM;
		goto fail_close;
	}

	ret = vmbus_establish_gpadl(dev->channel, pdata->recv_buf,
				    RECV_BUFFER_SIZE, &pdata->recv_gpadl);
	if (ret)
		goto fail_close;

	/* put Global Physical Address Label in name */
	snprintf(pdata->recv_name, sizeof(pdata->recv_name),
		 "recv:%u", pdata->recv_gpadl);
	pdata->info.mem[RECV_BUF_MAP].name = pdata->recv_name;
	pdata->info.mem[RECV_BUF_MAP].addr
		= (uintptr_t)pdata->recv_buf;
	pdata->info.mem[RECV_BUF_MAP].size = RECV_BUFFER_SIZE;
	pdata->info.mem[RECV_BUF_MAP].memtype = UIO_MEM_VIRTUAL;


	pdata->send_buf = vzalloc(SEND_BUFFER_SIZE);
	if (pdata->send_buf == NULL) {
		ret = -ENOMEM;
		goto fail_close;
	}

	ret = vmbus_establish_gpadl(dev->channel, pdata->send_buf,
				    SEND_BUFFER_SIZE, &pdata->send_gpadl);
	if (ret)
		goto fail_close;

	snprintf(pdata->send_name, sizeof(pdata->send_name),
		 "send:%u", pdata->send_gpadl);
	pdata->info.mem[SEND_BUF_MAP].name = pdata->send_name;
	pdata->info.mem[SEND_BUF_MAP].addr
		= (uintptr_t)pdata->send_buf;
	pdata->info.mem[SEND_BUF_MAP].size = SEND_BUFFER_SIZE;
	pdata->info.mem[SEND_BUF_MAP].memtype = UIO_MEM_VIRTUAL;

	pdata->info.priv = pdata;
	pdata->device = dev;

	ret = uio_register_device(&dev->device, &pdata->info);
	if (ret) {
		dev_err(&dev->device, "hv_uio register failed\n");
		goto fail_close;
	}

	vmbus_set_chn_rescind_callback(dev->channel, hv_uio_rescind);

	hv_set_drvdata(dev, pdata);

	return 0;

fail_close:
	hv_uio_cleanup(dev, pdata);
	vmbus_close(dev->channel);
fail:
	kfree(pdata);

	return ret;
}

static int
hv_uio_remove(struct hv_device *dev)
{
	struct hv_uio_private_data *pdata = hv_get_drvdata(dev);

	if (!pdata)
		return 0;

	uio_unregister_device(&pdata->info);
	hv_uio_cleanup(dev, pdata);
	hv_set_drvdata(dev, NULL);
	vmbus_close(dev->channel);
	kfree(pdata);
	return 0;
}

static struct hv_driver hv_uio_drv = {
	.name = "uio_hv_generic",
	.id_table = NULL, /* only dynamic id's */
	.probe = hv_uio_probe,
	.remove = hv_uio_remove,
};

static int __init
hyperv_module_init(void)
{
	return vmbus_driver_register(&hv_uio_drv);
}

static void __exit
hyperv_module_exit(void)
{
	vmbus_driver_unregister(&hv_uio_drv);
}

module_init(hyperv_module_init);
module_exit(hyperv_module_exit);

MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
Commit	Line	Data
95096f2f SH	1	/*
	2	* uio_hv_generic - generic UIO driver for VMBus
	3	*
	4	* Copyright (c) 2013-2016 Brocade Communications Systems, Inc.
	5	* Copyright (c) 2016, Microsoft Corporation.
	6	*
	7	*
	8	* This work is licensed under the terms of the GNU GPL, version 2.
	9	*
	10	* Since the driver does not declare any device ids, you must allocate
	11	* id and bind the device to the driver yourself. For example:
	12	*
42896968	13	* Associate Network GUID with UIO device
95096f2f	14	* # echo "f8615163-df3e-46c5-913f-f2d2f965ed0e" \
42896968 SH	15	* > /sys/bus/vmbus/drivers/uio_hv_generic/new_id
	16	* Then rebind
	17	* # echo -n "ed963694-e847-4b2a-85af-bc9cfc11d6f3" \
95096f2f	18	* > /sys/bus/vmbus/drivers/hv_netvsc/unbind
42896968	19	* # echo -n "ed963694-e847-4b2a-85af-bc9cfc11d6f3" \
95096f2f SH	20	* > /sys/bus/vmbus/drivers/uio_hv_generic/bind
	21	*/
	22
	23	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	24
	25	#include <linux/device.h>
	26	#include <linux/kernel.h>
	27	#include <linux/module.h>
	28	#include <linux/uio_driver.h>
	29	#include <linux/netdevice.h>
	30	#include <linux/if_ether.h>
	31	#include <linux/skbuff.h>
	32	#include <linux/hyperv.h>
	33	#include <linux/vmalloc.h>
	34	#include <linux/slab.h>
	35
	36	#include "../hv/hyperv_vmbus.h"
	37
	38	#define DRIVER_VERSION "0.02.0"
	39	#define DRIVER_AUTHOR "Stephen Hemminger <sthemmin at microsoft.com>"
	40	#define DRIVER_DESC "Generic UIO driver for VMBus devices"
	41
e7d21464 SH	42	#define HV_RING_SIZE 512 /* pages */
	43	#define SEND_BUFFER_SIZE (15 * 1024 * 1024)
	44	#define RECV_BUFFER_SIZE (15 * 1024 * 1024)
	45
95096f2f SH	46	/*
	47	* List of resources to be mapped to user space
	48	* can be extended up to MAX_UIO_MAPS(5) items
	49	*/
	50	enum hv_uio_map {
	51	TXRX_RING_MAP = 0,
	52	INT_PAGE_MAP,
	53	MON_PAGE_MAP,
e7d21464 SH	54	RECV_BUF_MAP,
e7d21464 SH	55	SEND_BUF_MAP
95096f2f SH	56	};
95096f2f SH	57
95096f2f SH	58	struct hv_uio_private_data {
	59	struct uio_info info;
	60	struct hv_device *device;
e7d21464 SH	61
	62	void *recv_buf;
	63	u32 recv_gpadl;
	64	char recv_name[32]; /* "recv_4294967295" */
	65
	66	void *send_buf;
	67	u32 send_gpadl;
	68	char send_name[32];
95096f2f SH	69	};
95096f2f SH	70
95096f2f SH	71	/*
	72	* This is the irqcontrol callback to be registered to uio_info.
	73	* It can be used to disable/enable interrupt from user space processes.
	74	*
	75	* @param info
	76	* pointer to uio_info.
	77	* @param irq_state
	78	* state value. 1 to enable interrupt, 0 to disable interrupt.
	79	*/
	80	static int
	81	hv_uio_irqcontrol(struct uio_info *info, s32 irq_state)
	82	{
	83	struct hv_uio_private_data *pdata = info->priv;
	84	struct hv_device *dev = pdata->device;
	85
	86	dev->channel->inbound.ring_buffer->interrupt_mask = !irq_state;
	87	virt_mb();
	88
	89	return 0;
	90	}
	91
	92	/*
	93	* Callback from vmbus_event when something is in inbound ring.
	94	*/
	95	static void hv_uio_channel_cb(void *context)
	96	{
	97	struct hv_uio_private_data *pdata = context;
	98	struct hv_device *dev = pdata->device;
	99
	100	dev->channel->inbound.ring_buffer->interrupt_mask = 1;
	101	virt_mb();
	102
	103	uio_event_notify(&pdata->info);
	104	}
	105
ca3cda6f SH	106	/*
	107	* Callback from vmbus_event when channel is rescinded.
	108	*/
	109	static void hv_uio_rescind(struct vmbus_channel *channel)
	110	{
	111	struct hv_device *hv_dev = channel->primary_channel->device_obj;
	112	struct hv_uio_private_data *pdata = hv_get_drvdata(hv_dev);
	113
	114	/*
	115	* Turn off the interrupt file handle
	116	* Next read for event will return -EIO
	117	*/
	118	pdata->info.irq = 0;
	119
	120	/* Wake up reader */
	121	uio_event_notify(&pdata->info);
	122	}
e7d21464 SH	123
	124	static void
	125	hv_uio_cleanup(struct hv_device dev, struct hv_uio_private_data pdata)
	126	{
	127	if (pdata->send_gpadl)
	128	vmbus_teardown_gpadl(dev->channel, pdata->send_gpadl);
	129	vfree(pdata->send_buf);
	130
	131	if (pdata->recv_gpadl)
	132	vmbus_teardown_gpadl(dev->channel, pdata->recv_gpadl);
	133	vfree(pdata->recv_buf);
	134	}
	135
95096f2f SH	136	static int
	137	hv_uio_probe(struct hv_device *dev,
	138	const struct hv_vmbus_device_id *dev_id)
	139	{
	140	struct hv_uio_private_data *pdata;
	141	int ret;
	142
	143	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
	144	if (!pdata)
	145	return -ENOMEM;
	146
	147	ret = vmbus_open(dev->channel, HV_RING_SIZE * PAGE_SIZE,
	148	HV_RING_SIZE * PAGE_SIZE, NULL, 0,
	149	hv_uio_channel_cb, pdata);
	150	if (ret)
	151	goto fail;
	152
06028d15 SH	153	/* Communicating with host has to be via shared memory not hypercall */
	154	if (!dev->channel->offermsg.monitor_allocated) {
	155	dev_err(&dev->device, "vmbus channel requires hypercall\n");
	156	ret = -ENOTSUPP;
	157	goto fail_close;
	158	}
	159
95096f2f	160	dev->channel->inbound.ring_buffer->interrupt_mask = 1;
2141a845	161	set_channel_read_mode(dev->channel, HV_CALL_ISR);
95096f2f SH	162
	163	/* Fill general uio info */
	164	pdata->info.name = "uio_hv_generic";
	165	pdata->info.version = DRIVER_VERSION;
	166	pdata->info.irqcontrol = hv_uio_irqcontrol;
95096f2f SH	167	pdata->info.irq = UIO_IRQ_CUSTOM;
	168
	169	/* mem resources */
	170	pdata->info.mem[TXRX_RING_MAP].name = "txrx_rings";
	171	pdata->info.mem[TXRX_RING_MAP].addr
72d14657	172	= (uintptr_t)dev->channel->ringbuffer_pages;
95096f2f	173	pdata->info.mem[TXRX_RING_MAP].size
9c40546c	174	= dev->channel->ringbuffer_pagecount << PAGE_SHIFT;
95096f2f SH	175	pdata->info.mem[TXRX_RING_MAP].memtype = UIO_MEM_LOGICAL;
	176
	177	pdata->info.mem[INT_PAGE_MAP].name = "int_page";
9c40546c	178	pdata->info.mem[INT_PAGE_MAP].addr
72d14657	179	= (uintptr_t)vmbus_connection.int_page;
95096f2f SH	180	pdata->info.mem[INT_PAGE_MAP].size = PAGE_SIZE;
	181	pdata->info.mem[INT_PAGE_MAP].memtype = UIO_MEM_LOGICAL;
	182
9c40546c SH	183	pdata->info.mem[MON_PAGE_MAP].name = "monitor_page";
9c40546c SH	184	pdata->info.mem[MON_PAGE_MAP].addr
72d14657	185	= (uintptr_t)vmbus_connection.monitor_pages[1];
95096f2f SH	186	pdata->info.mem[MON_PAGE_MAP].size = PAGE_SIZE;
	187	pdata->info.mem[MON_PAGE_MAP].memtype = UIO_MEM_LOGICAL;
	188
e7d21464 SH	189	pdata->recv_buf = vzalloc(RECV_BUFFER_SIZE);
	190	if (pdata->recv_buf == NULL) {
	191	ret = -ENOMEM;
	192	goto fail_close;
	193	}
	194
	195	ret = vmbus_establish_gpadl(dev->channel, pdata->recv_buf,
	196	RECV_BUFFER_SIZE, &pdata->recv_gpadl);
	197	if (ret)
	198	goto fail_close;
	199
	200	/* put Global Physical Address Label in name */
	201	snprintf(pdata->recv_name, sizeof(pdata->recv_name),
	202	"recv:%u", pdata->recv_gpadl);
	203	pdata->info.mem[RECV_BUF_MAP].name = pdata->recv_name;
	204	pdata->info.mem[RECV_BUF_MAP].addr
d6088e9a	205	= (uintptr_t)pdata->recv_buf;
e7d21464 SH	206	pdata->info.mem[RECV_BUF_MAP].size = RECV_BUFFER_SIZE;
	207	pdata->info.mem[RECV_BUF_MAP].memtype = UIO_MEM_VIRTUAL;
	208
	209
	210	pdata->send_buf = vzalloc(SEND_BUFFER_SIZE);
	211	if (pdata->send_buf == NULL) {
	212	ret = -ENOMEM;
	213	goto fail_close;
	214	}
	215
	216	ret = vmbus_establish_gpadl(dev->channel, pdata->send_buf,
	217	SEND_BUFFER_SIZE, &pdata->send_gpadl);
	218	if (ret)
	219	goto fail_close;
	220
	221	snprintf(pdata->send_name, sizeof(pdata->send_name),
	222	"send:%u", pdata->send_gpadl);
	223	pdata->info.mem[SEND_BUF_MAP].name = pdata->send_name;
	224	pdata->info.mem[SEND_BUF_MAP].addr
d6088e9a	225	= (uintptr_t)pdata->send_buf;
e7d21464 SH	226	pdata->info.mem[SEND_BUF_MAP].size = SEND_BUFFER_SIZE;
	227	pdata->info.mem[SEND_BUF_MAP].memtype = UIO_MEM_VIRTUAL;
	228
95096f2f SH	229	pdata->info.priv = pdata;
	230	pdata->device = dev;
	231
	232	ret = uio_register_device(&dev->device, &pdata->info);
	233	if (ret) {
	234	dev_err(&dev->device, "hv_uio register failed\n");
	235	goto fail_close;
	236	}
	237
ca3cda6f SH	238	vmbus_set_chn_rescind_callback(dev->channel, hv_uio_rescind);
ca3cda6f SH	239
95096f2f SH	240	hv_set_drvdata(dev, pdata);
	241
	242	return 0;
	243
	244	fail_close:
e7d21464	245	hv_uio_cleanup(dev, pdata);
95096f2f SH	246	vmbus_close(dev->channel);
	247	fail:
	248	kfree(pdata);
	249
	250	return ret;
	251	}
	252
	253	static int
	254	hv_uio_remove(struct hv_device *dev)
	255	{
	256	struct hv_uio_private_data *pdata = hv_get_drvdata(dev);
	257
	258	if (!pdata)
	259	return 0;
	260
	261	uio_unregister_device(&pdata->info);
e7d21464	262	hv_uio_cleanup(dev, pdata);
95096f2f SH	263	hv_set_drvdata(dev, NULL);
	264	vmbus_close(dev->channel);
	265	kfree(pdata);
	266	return 0;
	267	}
	268
	269	static struct hv_driver hv_uio_drv = {
	270	.name = "uio_hv_generic",
	271	.id_table = NULL, /* only dynamic id's */
	272	.probe = hv_uio_probe,
	273	.remove = hv_uio_remove,
	274	};
	275
	276	static int __init
	277	hyperv_module_init(void)
	278	{
	279	return vmbus_driver_register(&hv_uio_drv);
	280	}
	281
	282	static void __exit
	283	hyperv_module_exit(void)
	284	{
	285	vmbus_driver_unregister(&hv_uio_drv);
	286	}
	287
	288	module_init(hyperv_module_init);
	289	module_exit(hyperv_module_exit);
	290
	291	MODULE_VERSION(DRIVER_VERSION);
	292	MODULE_LICENSE("GPL v2");
	293	MODULE_AUTHOR(DRIVER_AUTHOR);
	294	MODULE_DESCRIPTION(DRIVER_DESC);