[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;
	int rc = 0;

	if (!dmb_desc->dma_addr)
		return rc;

	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;
	rc = smcd->ops->unregister_dmb(smcd, &dmb);
	if (!rc || rc == ISM_ERROR) {
		dmb_desc->cpu_addr = NULL;
		dmb_desc->dma_addr = 0;
	}

	return rc;
}

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;

	if (lgr->peer_shutdown)
		return 0;

	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;
	if (smc_pnetid_by_dev_port(parent, 0, smcd->pnetid))
		smc_pnetid_by_table_smcd(smcd);

	spin_lock_init(&smcd->lock);
	spin_lock_init(&smcd->lgr_lock);
	INIT_LIST_HEAD(&smcd->vlan);
	INIT_LIST_HEAD(&smcd->lgr_list);
	init_waitqueue_head(&smcd->lgrs_deleted);
	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
						 WQ_MEM_RECLAIM, name);
	if (!smcd->event_wq) {
		kfree(smcd->conn);
		kfree(smcd);
		return NULL;
	}
	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);

	pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n",
			    dev_name(&smcd->dev), smcd->pnetid,
			    smcd->pnetid_by_user ? " (user defined)" : "");

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

void smcd_unregister_dev(struct smcd_dev *smcd)
{
	pr_warn_ratelimited("smc: removing smcd device %s\n",
			    dev_name(&smcd->dev));
	spin_lock(&smcd_dev_list.lock);
	list_del_init(&smcd->list);
	spin_unlock(&smcd_dev_list.lock);
	smcd->going_away = 1;
	smc_smcd_terminate_all(smcd);
	flush_workqueue(smcd->event_wq);
	destroy_workqueue(smcd->event_wq);

	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;

	if (smcd->going_away)
		return;
	/* 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 && !conn->killed)
		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;
42bfba9e UB	149	int rc = 0;
	150
	151	if (!dmb_desc->dma_addr)
	152	return rc;
c6ba7c9b HW	153
	154	memset(&dmb, 0, sizeof(dmb));
	155	dmb.dmb_tok = dmb_desc->token;
	156	dmb.sba_idx = dmb_desc->sba_idx;
	157	dmb.cpu_addr = dmb_desc->cpu_addr;
	158	dmb.dma_addr = dmb_desc->dma_addr;
	159	dmb.dmb_len = dmb_desc->len;
42bfba9e UB	160	rc = smcd->ops->unregister_dmb(smcd, &dmb);
	161	if (!rc \|\| rc == ISM_ERROR) {
	162	dmb_desc->cpu_addr = NULL;
	163	dmb_desc->dma_addr = 0;
	164	}
	165
	166	return rc;
c6ba7c9b HW	167	}
	168
	169	int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
	170	struct smc_buf_desc *dmb_desc)
	171	{
	172	struct smcd_dmb dmb;
	173	int rc;
	174
	175	memset(&dmb, 0, sizeof(dmb));
	176	dmb.dmb_len = dmb_len;
	177	dmb.sba_idx = dmb_desc->sba_idx;
	178	dmb.vlan_id = lgr->vlan_id;
	179	dmb.rgid = lgr->peer_gid;
	180	rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb);
	181	if (!rc) {
	182	dmb_desc->sba_idx = dmb.sba_idx;
	183	dmb_desc->token = dmb.dmb_tok;
	184	dmb_desc->cpu_addr = dmb.cpu_addr;
	185	dmb_desc->dma_addr = dmb.dma_addr;
	186	dmb_desc->len = dmb.dmb_len;
	187	}
	188	return rc;
	189	}
	190
	191	struct smc_ism_event_work {
	192	struct work_struct work;
	193	struct smcd_dev *smcd;
	194	struct smcd_event event;
	195	};
	196
0d86caff UB	197	#define ISM_EVENT_REQUEST 0x0001
	198	#define ISM_EVENT_RESPONSE 0x0002
	199	#define ISM_EVENT_REQUEST_IR 0x00000001
0512f69e	200	#define ISM_EVENT_CODE_SHUTDOWN 0x80
0d86caff UB	201	#define ISM_EVENT_CODE_TESTLINK 0x83
0d86caff UB	202
0512f69e HW	203	union smcd_sw_event_info {
	204	u64 info;
	205	struct {
	206	u8 uid[SMC_LGR_ID_SIZE];
	207	unsigned short vlan_id;
	208	u16 code;
	209	};
	210	};
	211
0d86caff UB	212	static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
0d86caff UB	213	{
0512f69e	214	union smcd_sw_event_info ev_info;
0d86caff	215
0512f69e	216	ev_info.info = wrk->event.info;
0d86caff	217	switch (wrk->event.code) {
0512f69e HW	218	case ISM_EVENT_CODE_SHUTDOWN: /* Peer shut down DMBs */
	219	smc_smcd_terminate(wrk->smcd, wrk->event.tok, ev_info.vlan_id);
	220	break;
0d86caff	221	case ISM_EVENT_CODE_TESTLINK: /* Activity timer */
0d86caff UB	222	if (ev_info.code == ISM_EVENT_REQUEST) {
	223	ev_info.code = ISM_EVENT_RESPONSE;
	224	wrk->smcd->ops->signal_event(wrk->smcd,
	225	wrk->event.tok,
	226	ISM_EVENT_REQUEST_IR,
	227	ISM_EVENT_CODE_TESTLINK,
	228	ev_info.info);
	229	}
	230	break;
	231	}
	232	}
	233
0512f69e HW	234	int smc_ism_signal_shutdown(struct smc_link_group *lgr)
	235	{
	236	int rc;
	237	union smcd_sw_event_info ev_info;
	238
50c6b20e UB	239	if (lgr->peer_shutdown)
	240	return 0;
	241
0512f69e HW	242	memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
	243	ev_info.vlan_id = lgr->vlan_id;
	244	ev_info.code = ISM_EVENT_REQUEST;
	245	rc = lgr->smcd->ops->signal_event(lgr->smcd, lgr->peer_gid,
	246	ISM_EVENT_REQUEST_IR,
	247	ISM_EVENT_CODE_SHUTDOWN,
	248	ev_info.info);
	249	return rc;
	250	}
	251
c6ba7c9b HW	252	/* worker for SMC-D events */
	253	static void smc_ism_event_work(struct work_struct *work)
	254	{
	255	struct smc_ism_event_work *wrk =
	256	container_of(work, struct smc_ism_event_work, work);
	257
	258	switch (wrk->event.type) {
	259	case ISM_EVENT_GID: /* GID event, token is peer GID */
0512f69e	260	smc_smcd_terminate(wrk->smcd, wrk->event.tok, VLAN_VID_MASK);
c6ba7c9b HW	261	break;
	262	case ISM_EVENT_DMB:
	263	break;
0d86caff UB	264	case ISM_EVENT_SWR: /* Software defined event */
	265	smcd_handle_sw_event(wrk);
	266	break;
c6ba7c9b HW	267	}
	268	kfree(wrk);
	269	}
	270
	271	static void smcd_release(struct device *dev)
	272	{
	273	struct smcd_dev *smcd = container_of(dev, struct smcd_dev, dev);
	274
	275	kfree(smcd->conn);
	276	kfree(smcd);
	277	}
	278
	279	struct smcd_dev smcd_alloc_dev(struct device parent, const char *name,
	280	const struct smcd_ops *ops, int max_dmbs)
	281	{
	282	struct smcd_dev *smcd;
	283
	284	smcd = kzalloc(sizeof(*smcd), GFP_KERNEL);
	285	if (!smcd)
	286	return NULL;
	287	smcd->conn = kcalloc(max_dmbs, sizeof(struct smc_connection *),
	288	GFP_KERNEL);
	289	if (!smcd->conn) {
	290	kfree(smcd);
	291	return NULL;
	292	}
	293
	294	smcd->dev.parent = parent;
	295	smcd->dev.release = smcd_release;
	296	device_initialize(&smcd->dev);
	297	dev_set_name(&smcd->dev, name);
	298	smcd->ops = ops;
fdff704d KG	299	if (smc_pnetid_by_dev_port(parent, 0, smcd->pnetid))
fdff704d KG	300	smc_pnetid_by_table_smcd(smcd);
c6ba7c9b HW	301
c6ba7c9b HW	302	spin_lock_init(&smcd->lock);
a0a62ee1	303	spin_lock_init(&smcd->lgr_lock);
c6ba7c9b	304	INIT_LIST_HEAD(&smcd->vlan);
a2351c5d	305	INIT_LIST_HEAD(&smcd->lgr_list);
5edd6b9c	306	init_waitqueue_head(&smcd->lgrs_deleted);
c6ba7c9b HW	307	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
c6ba7c9b HW	308	WQ_MEM_RECLAIM, name);
e183d4e4 KL	309	if (!smcd->event_wq) {
	310	kfree(smcd->conn);
	311	kfree(smcd);
	312	return NULL;
	313	}
c6ba7c9b HW	314	return smcd;
	315	}
	316	EXPORT_SYMBOL_GPL(smcd_alloc_dev);
	317
	318	int smcd_register_dev(struct smcd_dev *smcd)
	319	{
	320	spin_lock(&smcd_dev_list.lock);
	321	list_add_tail(&smcd->list, &smcd_dev_list.list);
	322	spin_unlock(&smcd_dev_list.lock);
	323
0a99be43 KG	324	pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n",
	325	dev_name(&smcd->dev), smcd->pnetid,
	326	smcd->pnetid_by_user ? " (user defined)" : "");
	327
c6ba7c9b HW	328	return device_add(&smcd->dev);
	329	}
	330	EXPORT_SYMBOL_GPL(smcd_register_dev);
	331
	332	void smcd_unregister_dev(struct smcd_dev *smcd)
	333	{
0a99be43 KG	334	pr_warn_ratelimited("smc: removing smcd device %s\n",
0a99be43 KG	335	dev_name(&smcd->dev));
c6ba7c9b	336	spin_lock(&smcd_dev_list.lock);
50c6b20e	337	list_del_init(&smcd->list);
c6ba7c9b	338	spin_unlock(&smcd_dev_list.lock);
c3d9494e	339	smcd->going_away = 1;
5421ec28	340	smc_smcd_terminate_all(smcd);
c6ba7c9b HW	341	flush_workqueue(smcd->event_wq);
c6ba7c9b HW	342	destroy_workqueue(smcd->event_wq);
c6ba7c9b HW	343
	344	device_del(&smcd->dev);
	345	}
	346	EXPORT_SYMBOL_GPL(smcd_unregister_dev);
	347
	348	void smcd_free_dev(struct smcd_dev *smcd)
	349	{
	350	put_device(&smcd->dev);
	351	}
	352	EXPORT_SYMBOL_GPL(smcd_free_dev);
	353
	354	/* SMCD Device event handler. Called from ISM device interrupt handler.
	355	* Parameters are smcd device pointer,
	356	* - event->type (0 --> DMB, 1 --> GID),
	357	* - event->code (event code),
	358	* - event->tok (either DMB token when event type 0, or GID when event type 1)
	359	* - event->time (time of day)
	360	* - event->info (debug info).
	361	*
	362	* Context:
	363	* - Function called in IRQ context from ISM device driver event handler.
	364	*/
	365	void smcd_handle_event(struct smcd_dev smcd, struct smcd_event event)
	366	{
	367	struct smc_ism_event_work *wrk;
	368
c3d9494e UB	369	if (smcd->going_away)
c3d9494e UB	370	return;
c6ba7c9b HW	371	/* copy event to event work queue, and let it be handled there */
	372	wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC);
	373	if (!wrk)
	374	return;
	375	INIT_WORK(&wrk->work, smc_ism_event_work);
	376	wrk->smcd = smcd;
	377	wrk->event = *event;
	378	queue_work(smcd->event_wq, &wrk->work);
	379	}
	380	EXPORT_SYMBOL_GPL(smcd_handle_event);
	381
	382	/* SMCD Device interrupt handler. Called from ISM device interrupt handler.
	383	* Parameters are smcd device pointer and DMB number. Find the connection and
	384	* schedule the tasklet for this connection.
	385	*
	386	* Context:
	387	* - Function called in IRQ context from ISM device driver IRQ handler.
	388	*/
	389	void smcd_handle_irq(struct smcd_dev *smcd, unsigned int dmbno)
	390	{
be244f28 HW	391	struct smc_connection *conn = NULL;
	392	unsigned long flags;
	393
	394	spin_lock_irqsave(&smcd->lock, flags);
	395	conn = smcd->conn[dmbno];
42bfba9e	396	if (conn && !conn->killed)
be244f28 HW	397	tasklet_schedule(&conn->rx_tsklet);
be244f28 HW	398	spin_unlock_irqrestore(&smcd->lock, flags);
c6ba7c9b HW	399	}
c6ba7c9b HW	400	EXPORT_SYMBOL_GPL(smcd_handle_irq);