[linux.git] / net / smc / smc_ism.c

// SPDX-License-Identifier: GPL-2.0
/* Shared Memory Communications Direct over ISM devices (SMC-D)
 *
 * Functions for ISM device.
 *
 * Copyright IBM Corp. 2018
 */

#include <linux/spinlock.h>
#include <linux/slab.h>
#include <asm/page.h>

#include "smc.h"
#include "smc_core.h"
#include "smc_ism.h"
#include "smc_pnet.h"

struct smcd_dev_list smcd_dev_list = {
	.list = LIST_HEAD_INIT(smcd_dev_list.list),
	.lock = __SPIN_LOCK_UNLOCKED(smcd_dev_list.lock)
};

/* Test if an ISM communication is possible. */
int smc_ism_cantalk(u64 peer_gid, unsigned short vlan_id, struct smcd_dev *smcd)
{
	return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0,
					   vlan_id);
}

int smc_ism_write(struct smcd_dev *smcd, const struct smc_ism_position *pos,
		  void *data, size_t len)
{
	int rc;

	rc = smcd->ops->move_data(smcd, pos->token, pos->index, pos->signal,
				  pos->offset, data, len);

	return rc < 0 ? rc : 0;
}

/* Set a connection using this DMBE. */
void smc_ism_set_conn(struct smc_connection *conn)
{
	unsigned long flags;

	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn;
	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
}

/* Unset a connection using this DMBE. */
void smc_ism_unset_conn(struct smc_connection *conn)
{
	unsigned long flags;

	if (!conn->rmb_desc)
		return;

	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL;
	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
}

/* Register a VLAN identifier with the ISM device. Use a reference count
 * and add a VLAN identifier only when the first DMB using this VLAN is
 * registered.
 */
int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
{
	struct smc_ism_vlanid *new_vlan, *vlan;
	unsigned long flags;
	int rc = 0;

	if (!vlanid)			/* No valid vlan id */
		return -EINVAL;

	/* create new vlan entry, in case we need it */
	new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL);
	if (!new_vlan)
		return -ENOMEM;
	new_vlan->vlanid = vlanid;
	refcount_set(&new_vlan->refcnt, 1);

	/* if there is an existing entry, increase count and return */
	spin_lock_irqsave(&smcd->lock, flags);
	list_for_each_entry(vlan, &smcd->vlan, list) {
		if (vlan->vlanid == vlanid) {
			refcount_inc(&vlan->refcnt);
			kfree(new_vlan);
			goto out;
		}
	}

	/* no existing entry found.
	 * add new entry to device; might fail, e.g., if HW limit reached
	 */
	if (smcd->ops->add_vlan_id(smcd, vlanid)) {
		kfree(new_vlan);
		rc = -EIO;
		goto out;
	}
	list_add_tail(&new_vlan->list, &smcd->vlan);
out:
	spin_unlock_irqrestore(&smcd->lock, flags);
	return rc;
}

/* Unregister a VLAN identifier with the ISM device. Use a reference count
 * and remove a VLAN identifier only when the last DMB using this VLAN is
 * unregistered.
 */
int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
{
	struct smc_ism_vlanid *vlan;
	unsigned long flags;
	bool found = false;
	int rc = 0;

	if (!vlanid)			/* No valid vlan id */
		return -EINVAL;

	spin_lock_irqsave(&smcd->lock, flags);
	list_for_each_entry(vlan, &smcd->vlan, list) {
		if (vlan->vlanid == vlanid) {
			if (!refcount_dec_and_test(&vlan->refcnt))
				goto out;
			found = true;
			break;
		}
	}
	if (!found) {
		rc = -ENOENT;
		goto out;		/* VLAN id not in table */
	}

	/* Found and the last reference just gone */
	if (smcd->ops->del_vlan_id(smcd, vlanid))
		rc = -EIO;
	list_del(&vlan->list);
	kfree(vlan);
out:
	spin_unlock_irqrestore(&smcd->lock, flags);
	return rc;
}

int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc)
{
	struct smcd_dmb dmb;

	memset(&dmb, 0, sizeof(dmb));
	dmb.dmb_tok = dmb_desc->token;
	dmb.sba_idx = dmb_desc->sba_idx;
	dmb.cpu_addr = dmb_desc->cpu_addr;
	dmb.dma_addr = dmb_desc->dma_addr;
	dmb.dmb_len = dmb_desc->len;
	return smcd->ops->unregister_dmb(smcd, &dmb);
}

int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
			 struct smc_buf_desc *dmb_desc)
{
	struct smcd_dmb dmb;
	int rc;

	memset(&dmb, 0, sizeof(dmb));
	dmb.dmb_len = dmb_len;
	dmb.sba_idx = dmb_desc->sba_idx;
	dmb.vlan_id = lgr->vlan_id;
	dmb.rgid = lgr->peer_gid;
	rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb);
	if (!rc) {
		dmb_desc->sba_idx = dmb.sba_idx;
		dmb_desc->token = dmb.dmb_tok;
		dmb_desc->cpu_addr = dmb.cpu_addr;
		dmb_desc->dma_addr = dmb.dma_addr;
		dmb_desc->len = dmb.dmb_len;
	}
	return rc;
}

struct smc_ism_event_work {
	struct work_struct work;
	struct smcd_dev *smcd;
	struct smcd_event event;
};

#define ISM_EVENT_REQUEST		0x0001
#define ISM_EVENT_RESPONSE		0x0002
#define ISM_EVENT_REQUEST_IR		0x00000001
#define ISM_EVENT_CODE_SHUTDOWN		0x80
#define ISM_EVENT_CODE_TESTLINK		0x83

union smcd_sw_event_info {
	u64	info;
	struct {
		u8		uid[SMC_LGR_ID_SIZE];
		unsigned short	vlan_id;
		u16		code;
	};
};

static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
{
	union smcd_sw_event_info ev_info;

	ev_info.info = wrk->event.info;
	switch (wrk->event.code) {
	case ISM_EVENT_CODE_SHUTDOWN:	/* Peer shut down DMBs */
		smc_smcd_terminate(wrk->smcd, wrk->event.tok, ev_info.vlan_id);
		break;
	case ISM_EVENT_CODE_TESTLINK:	/* Activity timer */
		if (ev_info.code == ISM_EVENT_REQUEST) {
			ev_info.code = ISM_EVENT_RESPONSE;
			wrk->smcd->ops->signal_event(wrk->smcd,
						     wrk->event.tok,
						     ISM_EVENT_REQUEST_IR,
						     ISM_EVENT_CODE_TESTLINK,
						     ev_info.info);
			}
		break;
	}
}

int smc_ism_signal_shutdown(struct smc_link_group *lgr)
{
	int rc;
	union smcd_sw_event_info ev_info;

	memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
	ev_info.vlan_id = lgr->vlan_id;
	ev_info.code = ISM_EVENT_REQUEST;
	rc = lgr->smcd->ops->signal_event(lgr->smcd, lgr->peer_gid,
					  ISM_EVENT_REQUEST_IR,
					  ISM_EVENT_CODE_SHUTDOWN,
					  ev_info.info);
	return rc;
}

/* worker for SMC-D events */
static void smc_ism_event_work(struct work_struct *work)
{
	struct smc_ism_event_work *wrk =
		container_of(work, struct smc_ism_event_work, work);

	switch (wrk->event.type) {
	case ISM_EVENT_GID:	/* GID event, token is peer GID */
		smc_smcd_terminate(wrk->smcd, wrk->event.tok, VLAN_VID_MASK);
		break;
	case ISM_EVENT_DMB:
		break;
	case ISM_EVENT_SWR:	/* Software defined event */
		smcd_handle_sw_event(wrk);
		break;
	}
	kfree(wrk);
}

static void smcd_release(struct device *dev)
{
	struct smcd_dev *smcd = container_of(dev, struct smcd_dev, dev);

	kfree(smcd->conn);
	kfree(smcd);
}

struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
				const struct smcd_ops *ops, int max_dmbs)
{
	struct smcd_dev *smcd;

	smcd = kzalloc(sizeof(*smcd), GFP_KERNEL);
	if (!smcd)
		return NULL;
	smcd->conn = kcalloc(max_dmbs, sizeof(struct smc_connection *),
			     GFP_KERNEL);
	if (!smcd->conn) {
		kfree(smcd);
		return NULL;
	}

	smcd->dev.parent = parent;
	smcd->dev.release = smcd_release;
	device_initialize(&smcd->dev);
	dev_set_name(&smcd->dev, name);
	smcd->ops = ops;
	smc_pnetid_by_dev_port(parent, 0, smcd->pnetid);

	spin_lock_init(&smcd->lock);
	INIT_LIST_HEAD(&smcd->vlan);
	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
						 WQ_MEM_RECLAIM, name);
	return smcd;
}
EXPORT_SYMBOL_GPL(smcd_alloc_dev);

int smcd_register_dev(struct smcd_dev *smcd)
{
	spin_lock(&smcd_dev_list.lock);
	list_add_tail(&smcd->list, &smcd_dev_list.list);
	spin_unlock(&smcd_dev_list.lock);

	return device_add(&smcd->dev);
}
EXPORT_SYMBOL_GPL(smcd_register_dev);

void smcd_unregister_dev(struct smcd_dev *smcd)
{
	spin_lock(&smcd_dev_list.lock);
	list_del(&smcd->list);
	spin_unlock(&smcd_dev_list.lock);
	flush_workqueue(smcd->event_wq);
	destroy_workqueue(smcd->event_wq);
	smc_smcd_terminate(smcd, 0, VLAN_VID_MASK);

	device_del(&smcd->dev);
}
EXPORT_SYMBOL_GPL(smcd_unregister_dev);

void smcd_free_dev(struct smcd_dev *smcd)
{
	put_device(&smcd->dev);
}
EXPORT_SYMBOL_GPL(smcd_free_dev);

/* SMCD Device event handler. Called from ISM device interrupt handler.
 * Parameters are smcd device pointer,
 * - event->type (0 --> DMB, 1 --> GID),
 * - event->code (event code),
 * - event->tok (either DMB token when event type 0, or GID when event type 1)
 * - event->time (time of day)
 * - event->info (debug info).
 *
 * Context:
 * - Function called in IRQ context from ISM device driver event handler.
 */
void smcd_handle_event(struct smcd_dev *smcd, struct smcd_event *event)
{
	struct smc_ism_event_work *wrk;

	/* copy event to event work queue, and let it be handled there */
	wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC);
	if (!wrk)
		return;
	INIT_WORK(&wrk->work, smc_ism_event_work);
	wrk->smcd = smcd;
	wrk->event = *event;
	queue_work(smcd->event_wq, &wrk->work);
}
EXPORT_SYMBOL_GPL(smcd_handle_event);

/* SMCD Device interrupt handler. Called from ISM device interrupt handler.
 * Parameters are smcd device pointer and DMB number. Find the connection and
 * schedule the tasklet for this connection.
 *
 * Context:
 * - Function called in IRQ context from ISM device driver IRQ handler.
 */
void smcd_handle_irq(struct smcd_dev *smcd, unsigned int dmbno)
{
	struct smc_connection *conn = NULL;
	unsigned long flags;

	spin_lock_irqsave(&smcd->lock, flags);
	conn = smcd->conn[dmbno];
	if (conn)
		tasklet_schedule(&conn->rx_tsklet);
	spin_unlock_irqrestore(&smcd->lock, flags);
}
EXPORT_SYMBOL_GPL(smcd_handle_irq);
Commit	Line	Data
c6ba7c9b HW	1	// SPDX-License-Identifier: GPL-2.0
	2	/* Shared Memory Communications Direct over ISM devices (SMC-D)
	3	*
	4	* Functions for ISM device.
	5	*
	6	* Copyright IBM Corp. 2018
	7	*/
	8
	9	#include <linux/spinlock.h>
	10	#include <linux/slab.h>
	11	#include <asm/page.h>
	12
	13	#include "smc.h"
	14	#include "smc_core.h"
	15	#include "smc_ism.h"
1619f770	16	#include "smc_pnet.h"
c6ba7c9b HW	17
	18	struct smcd_dev_list smcd_dev_list = {
	19	.list = LIST_HEAD_INIT(smcd_dev_list.list),
	20	.lock = __SPIN_LOCK_UNLOCKED(smcd_dev_list.lock)
	21	};
	22
	23	/* Test if an ISM communication is possible. */
	24	int smc_ism_cantalk(u64 peer_gid, unsigned short vlan_id, struct smcd_dev *smcd)
	25	{
	26	return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0,
	27	vlan_id);
	28	}
	29
	30	int smc_ism_write(struct smcd_dev smcd, const struct smc_ism_position pos,
	31	void *data, size_t len)
	32	{
	33	int rc;
	34
	35	rc = smcd->ops->move_data(smcd, pos->token, pos->index, pos->signal,
	36	pos->offset, data, len);
	37
	38	return rc < 0 ? rc : 0;
	39	}
	40
	41	/* Set a connection using this DMBE. */
	42	void smc_ism_set_conn(struct smc_connection *conn)
	43	{
	44	unsigned long flags;
	45
	46	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
	47	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn;
	48	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
	49	}
	50
	51	/* Unset a connection using this DMBE. */
	52	void smc_ism_unset_conn(struct smc_connection *conn)
	53	{
	54	unsigned long flags;
	55
	56	if (!conn->rmb_desc)
	57	return;
	58
	59	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
	60	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL;
	61	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
	62	}
	63
	64	/* Register a VLAN identifier with the ISM device. Use a reference count
	65	* and add a VLAN identifier only when the first DMB using this VLAN is
	66	* registered.
	67	*/
	68	int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
	69	{
	70	struct smc_ism_vlanid new_vlan, vlan;
	71	unsigned long flags;
	72	int rc = 0;
	73
	74	if (!vlanid) /* No valid vlan id */
	75	return -EINVAL;
	76
	77	/* create new vlan entry, in case we need it */
	78	new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL);
	79	if (!new_vlan)
	80	return -ENOMEM;
81	new_vlan->vlanid = vlanid;
82	refcount_set(&new_vlan->refcnt, 1);
83
84	/* if there is an existing entry, increase count and return */
85	spin_lock_irqsave(&smcd->lock, flags);
86	list_for_each_entry(vlan, &smcd->vlan, list) {
87	if (vlan->vlanid == vlanid) {
88	refcount_inc(&vlan->refcnt);
89	kfree(new_vlan);
90	goto out;
91	}
92	}
93
94	/* no existing entry found.
95	* add new entry to device; might fail, e.g., if HW limit reached
96	*/
97	if (smcd->ops->add_vlan_id(smcd, vlanid)) {
98	kfree(new_vlan);
99	rc = -EIO;
100	goto out;
101	}
102	list_add_tail(&new_vlan->list, &smcd->vlan);
103	out:
104	spin_unlock_irqrestore(&smcd->lock, flags);
105	return rc;
106	}
107
108	/* Unregister a VLAN identifier with the ISM device. Use a reference count
109	* and remove a VLAN identifier only when the last DMB using this VLAN is
110	* unregistered.
111	*/
112	int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
113	{
114	struct smc_ism_vlanid *vlan;
115	unsigned long flags;
116	bool found = false;
117	int rc = 0;
118
119	if (!vlanid) /* No valid vlan id */
120	return -EINVAL;
121
122	spin_lock_irqsave(&smcd->lock, flags);
123	list_for_each_entry(vlan, &smcd->vlan, list) {
124	if (vlan->vlanid == vlanid) {
125	if (!refcount_dec_and_test(&vlan->refcnt))
126	goto out;
127	found = true;
128	break;
129	}
130	}
131	if (!found) {
132	rc = -ENOENT;
133	goto out; /* VLAN id not in table */
134	}
135
136	/* Found and the last reference just gone */
137	if (smcd->ops->del_vlan_id(smcd, vlanid))
138	rc = -EIO;
139	list_del(&vlan->list);
140	kfree(vlan);
141	out:
142	spin_unlock_irqrestore(&smcd->lock, flags);
143	return rc;
144	}
145
146	int smc_ism_unregister_dmb(struct smcd_dev smcd, struct smc_buf_desc dmb_desc)
147	{
148	struct smcd_dmb dmb;
149
150	memset(&dmb, 0, sizeof(dmb));
151	dmb.dmb_tok = dmb_desc->token;
152	dmb.sba_idx = dmb_desc->sba_idx;
153	dmb.cpu_addr = dmb_desc->cpu_addr;
154	dmb.dma_addr = dmb_desc->dma_addr;
155	dmb.dmb_len = dmb_desc->len;
156	return smcd->ops->unregister_dmb(smcd, &dmb);
157	}
158
159	int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
160	struct smc_buf_desc *dmb_desc)
161	{
162	struct smcd_dmb dmb;
163	int rc;
164
165	memset(&dmb, 0, sizeof(dmb));
166	dmb.dmb_len = dmb_len;
167	dmb.sba_idx = dmb_desc->sba_idx;
168	dmb.vlan_id = lgr->vlan_id;
169	dmb.rgid = lgr->peer_gid;
170	rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb);
171	if (!rc) {
172	dmb_desc->sba_idx = dmb.sba_idx;
173	dmb_desc->token = dmb.dmb_tok;
174	dmb_desc->cpu_addr = dmb.cpu_addr;
175	dmb_desc->dma_addr = dmb.dma_addr;
176	dmb_desc->len = dmb.dmb_len;
177	}
178	return rc;
179	}
180
181	struct smc_ism_event_work {
182	struct work_struct work;
183	struct smcd_dev *smcd;
184	struct smcd_event event;
185	};
186
0d86caff UB	187	#define ISM_EVENT_REQUEST 0x0001
	188	#define ISM_EVENT_RESPONSE 0x0002
	189	#define ISM_EVENT_REQUEST_IR 0x00000001
0512f69e	190	#define ISM_EVENT_CODE_SHUTDOWN 0x80
0d86caff UB	191	#define ISM_EVENT_CODE_TESTLINK 0x83
0d86caff UB	192
0512f69e HW	193	union smcd_sw_event_info {
	194	u64 info;
	195	struct {
	196	u8 uid[SMC_LGR_ID_SIZE];
	197	unsigned short vlan_id;
	198	u16 code;
	199	};
	200	};
	201
0d86caff UB	202	static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
0d86caff UB	203	{
0512f69e	204	union smcd_sw_event_info ev_info;
0d86caff	205
0512f69e	206	ev_info.info = wrk->event.info;
0d86caff	207	switch (wrk->event.code) {
0512f69e HW	208	case ISM_EVENT_CODE_SHUTDOWN: /* Peer shut down DMBs */
	209	smc_smcd_terminate(wrk->smcd, wrk->event.tok, ev_info.vlan_id);
	210	break;
0d86caff	211	case ISM_EVENT_CODE_TESTLINK: /* Activity timer */
0d86caff UB	212	if (ev_info.code == ISM_EVENT_REQUEST) {
	213	ev_info.code = ISM_EVENT_RESPONSE;
	214	wrk->smcd->ops->signal_event(wrk->smcd,
	215	wrk->event.tok,
	216	ISM_EVENT_REQUEST_IR,
	217	ISM_EVENT_CODE_TESTLINK,
	218	ev_info.info);
	219	}
	220	break;
	221	}
	222	}
	223
0512f69e HW	224	int smc_ism_signal_shutdown(struct smc_link_group *lgr)
	225	{
	226	int rc;
	227	union smcd_sw_event_info ev_info;
	228
	229	memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
	230	ev_info.vlan_id = lgr->vlan_id;
	231	ev_info.code = ISM_EVENT_REQUEST;
	232	rc = lgr->smcd->ops->signal_event(lgr->smcd, lgr->peer_gid,
	233	ISM_EVENT_REQUEST_IR,
	234	ISM_EVENT_CODE_SHUTDOWN,
	235	ev_info.info);
	236	return rc;
	237	}
	238
c6ba7c9b HW	239	/* worker for SMC-D events */
	240	static void smc_ism_event_work(struct work_struct *work)
	241	{
	242	struct smc_ism_event_work *wrk =
	243	container_of(work, struct smc_ism_event_work, work);
	244
	245	switch (wrk->event.type) {
	246	case ISM_EVENT_GID: /* GID event, token is peer GID */
0512f69e	247	smc_smcd_terminate(wrk->smcd, wrk->event.tok, VLAN_VID_MASK);
c6ba7c9b HW	248	break;
	249	case ISM_EVENT_DMB:
	250	break;
0d86caff UB	251	case ISM_EVENT_SWR: /* Software defined event */
	252	smcd_handle_sw_event(wrk);
	253	break;
c6ba7c9b HW	254	}
	255	kfree(wrk);
	256	}
	257
	258	static void smcd_release(struct device *dev)
	259	{
	260	struct smcd_dev *smcd = container_of(dev, struct smcd_dev, dev);
	261
	262	kfree(smcd->conn);
	263	kfree(smcd);
	264	}
	265
	266	struct smcd_dev smcd_alloc_dev(struct device parent, const char *name,
	267	const struct smcd_ops *ops, int max_dmbs)
	268	{
	269	struct smcd_dev *smcd;
	270
	271	smcd = kzalloc(sizeof(*smcd), GFP_KERNEL);
	272	if (!smcd)
	273	return NULL;
	274	smcd->conn = kcalloc(max_dmbs, sizeof(struct smc_connection *),
	275	GFP_KERNEL);
	276	if (!smcd->conn) {
	277	kfree(smcd);
	278	return NULL;
	279	}
	280
	281	smcd->dev.parent = parent;
	282	smcd->dev.release = smcd_release;
	283	device_initialize(&smcd->dev);
	284	dev_set_name(&smcd->dev, name);
	285	smcd->ops = ops;
1619f770	286	smc_pnetid_by_dev_port(parent, 0, smcd->pnetid);
c6ba7c9b HW	287
	288	spin_lock_init(&smcd->lock);
	289	INIT_LIST_HEAD(&smcd->vlan);
	290	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
	291	WQ_MEM_RECLAIM, name);
	292	return smcd;
	293	}
	294	EXPORT_SYMBOL_GPL(smcd_alloc_dev);
	295
	296	int smcd_register_dev(struct smcd_dev *smcd)
	297	{
	298	spin_lock(&smcd_dev_list.lock);
	299	list_add_tail(&smcd->list, &smcd_dev_list.list);
	300	spin_unlock(&smcd_dev_list.lock);
	301
	302	return device_add(&smcd->dev);
	303	}
	304	EXPORT_SYMBOL_GPL(smcd_register_dev);
	305
	306	void smcd_unregister_dev(struct smcd_dev *smcd)
	307	{
	308	spin_lock(&smcd_dev_list.lock);
	309	list_del(&smcd->list);
	310	spin_unlock(&smcd_dev_list.lock);
	311	flush_workqueue(smcd->event_wq);
	312	destroy_workqueue(smcd->event_wq);
0512f69e	313	smc_smcd_terminate(smcd, 0, VLAN_VID_MASK);
c6ba7c9b HW	314
	315	device_del(&smcd->dev);
	316	}
	317	EXPORT_SYMBOL_GPL(smcd_unregister_dev);
	318
	319	void smcd_free_dev(struct smcd_dev *smcd)
	320	{
	321	put_device(&smcd->dev);
	322	}
	323	EXPORT_SYMBOL_GPL(smcd_free_dev);
	324
	325	/* SMCD Device event handler. Called from ISM device interrupt handler.
	326	* Parameters are smcd device pointer,
	327	* - event->type (0 --> DMB, 1 --> GID),
	328	* - event->code (event code),
	329	* - event->tok (either DMB token when event type 0, or GID when event type 1)
	330	* - event->time (time of day)
	331	* - event->info (debug info).
	332	*
	333	* Context:
	334	* - Function called in IRQ context from ISM device driver event handler.
	335	*/
	336	void smcd_handle_event(struct smcd_dev smcd, struct smcd_event event)
	337	{
	338	struct smc_ism_event_work *wrk;
	339
	340	/* copy event to event work queue, and let it be handled there */
	341	wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC);
	342	if (!wrk)
	343	return;
	344	INIT_WORK(&wrk->work, smc_ism_event_work);
	345	wrk->smcd = smcd;
	346	wrk->event = *event;
	347	queue_work(smcd->event_wq, &wrk->work);
	348	}
	349	EXPORT_SYMBOL_GPL(smcd_handle_event);
	350
	351	/* SMCD Device interrupt handler. Called from ISM device interrupt handler.
	352	* Parameters are smcd device pointer and DMB number. Find the connection and
	353	* schedule the tasklet for this connection.
	354	*
	355	* Context:
	356	* - Function called in IRQ context from ISM device driver IRQ handler.
	357	*/
	358	void smcd_handle_irq(struct smcd_dev *smcd, unsigned int dmbno)
	359	{
be244f28 HW	360	struct smc_connection *conn = NULL;
	361	unsigned long flags;
	362
	363	spin_lock_irqsave(&smcd->lock, flags);
	364	conn = smcd->conn[dmbno];
	365	if (conn)
	366	tasklet_schedule(&conn->rx_tsklet);
	367	spin_unlock_irqrestore(&smcd->lock, flags);
c6ba7c9b HW	368	}
c6ba7c9b HW	369	EXPORT_SYMBOL_GPL(smcd_handle_irq);