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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * SCSI RDMA (SRP) transport class4 *5 * Copyright (C) 2007 FUJITA Tomonori <tomof@acm.org>6 */7#include <linux/init.h>8#include <linux/module.h>9#include <linux/jiffies.h>10#include <linux/err.h>11#include <linux/slab.h>12#include <linux/string.h>13 14#include <scsi/scsi.h>15#include <scsi/scsi_cmnd.h>16#include <scsi/scsi_device.h>17#include <scsi/scsi_host.h>18#include <scsi/scsi_transport.h>19#include <scsi/scsi_transport_srp.h>20#include "scsi_priv.h"21 22struct srp_host_attrs {23	atomic_t next_port_id;24};25#define to_srp_host_attrs(host)	((struct srp_host_attrs *)(host)->shost_data)26 27#define SRP_HOST_ATTRS 028#define SRP_RPORT_ATTRS 829 30struct srp_internal {31	struct scsi_transport_template t;32	struct srp_function_template *f;33 34	struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1];35 36	struct device_attribute *rport_attrs[SRP_RPORT_ATTRS + 1];37	struct transport_container rport_attr_cont;38};39 40static int scsi_is_srp_rport(const struct device *dev);41 42#define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t)43 44#define	dev_to_rport(d)	container_of(d, struct srp_rport, dev)45#define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent)46static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r)47{48	return dev_to_shost(r->dev.parent);49}50 51static int find_child_rport(struct device *dev, void *data)52{53	struct device **child = data;54 55	if (scsi_is_srp_rport(dev)) {56		WARN_ON_ONCE(*child);57		*child = dev;58	}59	return 0;60}61 62static inline struct srp_rport *shost_to_rport(struct Scsi_Host *shost)63{64	struct device *child = NULL;65 66	WARN_ON_ONCE(device_for_each_child(&shost->shost_gendev, &child,67					   find_child_rport) < 0);68	return child ? dev_to_rport(child) : NULL;69}70 71/**72 * srp_tmo_valid() - check timeout combination validity73 * @reconnect_delay: Reconnect delay in seconds.74 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds.75 * @dev_loss_tmo: Device loss timeout in seconds.76 *77 * The combination of the timeout parameters must be such that SCSI commands78 * are finished in a reasonable time. Hence do not allow the fast I/O fail79 * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT nor allow dev_loss_tmo to80 * exceed that limit if failing I/O fast has been disabled. Furthermore, these81 * parameters must be such that multipath can detect failed paths timely.82 * Hence do not allow all three parameters to be disabled simultaneously.83 */84int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, long dev_loss_tmo)85{86	if (reconnect_delay < 0 && fast_io_fail_tmo < 0 && dev_loss_tmo < 0)87		return -EINVAL;88	if (reconnect_delay == 0)89		return -EINVAL;90	if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT)91		return -EINVAL;92	if (fast_io_fail_tmo < 0 &&93	    dev_loss_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT)94		return -EINVAL;95	if (dev_loss_tmo >= LONG_MAX / HZ)96		return -EINVAL;97	if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 &&98	    fast_io_fail_tmo >= dev_loss_tmo)99		return -EINVAL;100	return 0;101}102EXPORT_SYMBOL_GPL(srp_tmo_valid);103 104static int srp_host_setup(struct transport_container *tc, struct device *dev,105			  struct device *cdev)106{107	struct Scsi_Host *shost = dev_to_shost(dev);108	struct srp_host_attrs *srp_host = to_srp_host_attrs(shost);109 110	atomic_set(&srp_host->next_port_id, 0);111	return 0;112}113 114static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup,115			       NULL, NULL);116 117static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports",118			       NULL, NULL, NULL);119 120static ssize_t121show_srp_rport_id(struct device *dev, struct device_attribute *attr,122		  char *buf)123{124	struct srp_rport *rport = transport_class_to_srp_rport(dev);125	return sprintf(buf, "%16phC\n", rport->port_id);126}127 128static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL);129 130static const struct {131	u32 value;132	char *name;133} srp_rport_role_names[] = {134	{SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"},135	{SRP_RPORT_ROLE_TARGET, "SRP Target"},136};137 138static ssize_t139show_srp_rport_roles(struct device *dev, struct device_attribute *attr,140		     char *buf)141{142	struct srp_rport *rport = transport_class_to_srp_rport(dev);143	int i;144	char *name = NULL;145 146	for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++)147		if (srp_rport_role_names[i].value == rport->roles) {148			name = srp_rport_role_names[i].name;149			break;150		}151	return sprintf(buf, "%s\n", name ? : "unknown");152}153 154static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL);155 156static ssize_t store_srp_rport_delete(struct device *dev,157				      struct device_attribute *attr,158				      const char *buf, size_t count)159{160	struct srp_rport *rport = transport_class_to_srp_rport(dev);161	struct Scsi_Host *shost = dev_to_shost(dev);162	struct srp_internal *i = to_srp_internal(shost->transportt);163 164	if (i->f->rport_delete) {165		i->f->rport_delete(rport);166		return count;167	} else {168		return -ENOSYS;169	}170}171 172static DEVICE_ATTR(delete, S_IWUSR, NULL, store_srp_rport_delete);173 174static ssize_t show_srp_rport_state(struct device *dev,175				    struct device_attribute *attr,176				    char *buf)177{178	static const char *const state_name[] = {179		[SRP_RPORT_RUNNING]	= "running",180		[SRP_RPORT_BLOCKED]	= "blocked",181		[SRP_RPORT_FAIL_FAST]	= "fail-fast",182		[SRP_RPORT_LOST]	= "lost",183	};184	struct srp_rport *rport = transport_class_to_srp_rport(dev);185	enum srp_rport_state state = rport->state;186 187	return sprintf(buf, "%s\n",188		       (unsigned)state < ARRAY_SIZE(state_name) ?189		       state_name[state] : "???");190}191 192static DEVICE_ATTR(state, S_IRUGO, show_srp_rport_state, NULL);193 194static ssize_t srp_show_tmo(char *buf, int tmo)195{196	return tmo >= 0 ? sprintf(buf, "%d\n", tmo) : sprintf(buf, "off\n");197}198 199int srp_parse_tmo(int *tmo, const char *buf)200{201	int res = 0;202 203	if (strncmp(buf, "off", 3) != 0)204		res = kstrtoint(buf, 0, tmo);205	else206		*tmo = -1;207 208	return res;209}210EXPORT_SYMBOL(srp_parse_tmo);211 212static ssize_t show_reconnect_delay(struct device *dev,213				    struct device_attribute *attr, char *buf)214{215	struct srp_rport *rport = transport_class_to_srp_rport(dev);216 217	return srp_show_tmo(buf, rport->reconnect_delay);218}219 220static ssize_t store_reconnect_delay(struct device *dev,221				     struct device_attribute *attr,222				     const char *buf, const size_t count)223{224	struct srp_rport *rport = transport_class_to_srp_rport(dev);225	int res, delay;226 227	res = srp_parse_tmo(&delay, buf);228	if (res)229		goto out;230	res = srp_tmo_valid(delay, rport->fast_io_fail_tmo,231			    rport->dev_loss_tmo);232	if (res)233		goto out;234 235	if (rport->reconnect_delay <= 0 && delay > 0 &&236	    rport->state != SRP_RPORT_RUNNING) {237		queue_delayed_work(system_long_wq, &rport->reconnect_work,238				   delay * HZ);239	} else if (delay <= 0) {240		cancel_delayed_work(&rport->reconnect_work);241	}242	rport->reconnect_delay = delay;243	res = count;244 245out:246	return res;247}248 249static DEVICE_ATTR(reconnect_delay, S_IRUGO | S_IWUSR, show_reconnect_delay,250		   store_reconnect_delay);251 252static ssize_t show_failed_reconnects(struct device *dev,253				      struct device_attribute *attr, char *buf)254{255	struct srp_rport *rport = transport_class_to_srp_rport(dev);256 257	return sprintf(buf, "%d\n", rport->failed_reconnects);258}259 260static DEVICE_ATTR(failed_reconnects, S_IRUGO, show_failed_reconnects, NULL);261 262static ssize_t show_srp_rport_fast_io_fail_tmo(struct device *dev,263					       struct device_attribute *attr,264					       char *buf)265{266	struct srp_rport *rport = transport_class_to_srp_rport(dev);267 268	return srp_show_tmo(buf, rport->fast_io_fail_tmo);269}270 271static ssize_t store_srp_rport_fast_io_fail_tmo(struct device *dev,272						struct device_attribute *attr,273						const char *buf, size_t count)274{275	struct srp_rport *rport = transport_class_to_srp_rport(dev);276	int res;277	int fast_io_fail_tmo;278 279	res = srp_parse_tmo(&fast_io_fail_tmo, buf);280	if (res)281		goto out;282	res = srp_tmo_valid(rport->reconnect_delay, fast_io_fail_tmo,283			    rport->dev_loss_tmo);284	if (res)285		goto out;286	rport->fast_io_fail_tmo = fast_io_fail_tmo;287	res = count;288 289out:290	return res;291}292 293static DEVICE_ATTR(fast_io_fail_tmo, S_IRUGO | S_IWUSR,294		   show_srp_rport_fast_io_fail_tmo,295		   store_srp_rport_fast_io_fail_tmo);296 297static ssize_t show_srp_rport_dev_loss_tmo(struct device *dev,298					   struct device_attribute *attr,299					   char *buf)300{301	struct srp_rport *rport = transport_class_to_srp_rport(dev);302 303	return srp_show_tmo(buf, rport->dev_loss_tmo);304}305 306static ssize_t store_srp_rport_dev_loss_tmo(struct device *dev,307					    struct device_attribute *attr,308					    const char *buf, size_t count)309{310	struct srp_rport *rport = transport_class_to_srp_rport(dev);311	int res;312	int dev_loss_tmo;313 314	res = srp_parse_tmo(&dev_loss_tmo, buf);315	if (res)316		goto out;317	res = srp_tmo_valid(rport->reconnect_delay, rport->fast_io_fail_tmo,318			    dev_loss_tmo);319	if (res)320		goto out;321	rport->dev_loss_tmo = dev_loss_tmo;322	res = count;323 324out:325	return res;326}327 328static DEVICE_ATTR(dev_loss_tmo, S_IRUGO | S_IWUSR,329		   show_srp_rport_dev_loss_tmo,330		   store_srp_rport_dev_loss_tmo);331 332static int srp_rport_set_state(struct srp_rport *rport,333			       enum srp_rport_state new_state)334{335	enum srp_rport_state old_state = rport->state;336 337	lockdep_assert_held(&rport->mutex);338 339	switch (new_state) {340	case SRP_RPORT_RUNNING:341		switch (old_state) {342		case SRP_RPORT_LOST:343			goto invalid;344		default:345			break;346		}347		break;348	case SRP_RPORT_BLOCKED:349		switch (old_state) {350		case SRP_RPORT_RUNNING:351			break;352		default:353			goto invalid;354		}355		break;356	case SRP_RPORT_FAIL_FAST:357		switch (old_state) {358		case SRP_RPORT_LOST:359			goto invalid;360		default:361			break;362		}363		break;364	case SRP_RPORT_LOST:365		break;366	}367	rport->state = new_state;368	return 0;369 370invalid:371	return -EINVAL;372}373 374/**375 * srp_reconnect_work() - reconnect and schedule a new attempt if necessary376 * @work: Work structure used for scheduling this operation.377 */378static void srp_reconnect_work(struct work_struct *work)379{380	struct srp_rport *rport = container_of(to_delayed_work(work),381					struct srp_rport, reconnect_work);382	struct Scsi_Host *shost = rport_to_shost(rport);383	int delay, res;384 385	res = srp_reconnect_rport(rport);386	if (res != 0) {387		shost_printk(KERN_ERR, shost,388			     "reconnect attempt %d failed (%d)\n",389			     ++rport->failed_reconnects, res);390		delay = rport->reconnect_delay *391			min(100, max(1, rport->failed_reconnects - 10));392		if (delay > 0)393			queue_delayed_work(system_long_wq,394					   &rport->reconnect_work, delay * HZ);395	}396}397 398/*399 * scsi_block_targets() must have been called before this function is400 * called to guarantee that no .queuecommand() calls are in progress.401 */402static void __rport_fail_io_fast(struct srp_rport *rport)403{404	struct Scsi_Host *shost = rport_to_shost(rport);405	struct srp_internal *i;406 407	lockdep_assert_held(&rport->mutex);408 409	if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST))410		return;411 412	scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);413 414	/* Involve the LLD if possible to terminate all I/O on the rport. */415	i = to_srp_internal(shost->transportt);416	if (i->f->terminate_rport_io)417		i->f->terminate_rport_io(rport);418}419 420/**421 * rport_fast_io_fail_timedout() - fast I/O failure timeout handler422 * @work: Work structure used for scheduling this operation.423 */424static void rport_fast_io_fail_timedout(struct work_struct *work)425{426	struct srp_rport *rport = container_of(to_delayed_work(work),427					struct srp_rport, fast_io_fail_work);428	struct Scsi_Host *shost = rport_to_shost(rport);429 430	pr_info("fast_io_fail_tmo expired for SRP %s / %s.\n",431		dev_name(&rport->dev), dev_name(&shost->shost_gendev));432 433	mutex_lock(&rport->mutex);434	if (rport->state == SRP_RPORT_BLOCKED)435		__rport_fail_io_fast(rport);436	mutex_unlock(&rport->mutex);437}438 439/**440 * rport_dev_loss_timedout() - device loss timeout handler441 * @work: Work structure used for scheduling this operation.442 */443static void rport_dev_loss_timedout(struct work_struct *work)444{445	struct srp_rport *rport = container_of(to_delayed_work(work),446					struct srp_rport, dev_loss_work);447	struct Scsi_Host *shost = rport_to_shost(rport);448	struct srp_internal *i = to_srp_internal(shost->transportt);449 450	pr_info("dev_loss_tmo expired for SRP %s / %s.\n",451		dev_name(&rport->dev), dev_name(&shost->shost_gendev));452 453	mutex_lock(&rport->mutex);454	WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0);455	scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);456	mutex_unlock(&rport->mutex);457 458	i->f->rport_delete(rport);459}460 461static void __srp_start_tl_fail_timers(struct srp_rport *rport)462{463	struct Scsi_Host *shost = rport_to_shost(rport);464	int delay, fast_io_fail_tmo, dev_loss_tmo;465 466	lockdep_assert_held(&rport->mutex);467 468	delay = rport->reconnect_delay;469	fast_io_fail_tmo = rport->fast_io_fail_tmo;470	dev_loss_tmo = rport->dev_loss_tmo;471	pr_debug("%s current state: %d\n", dev_name(&shost->shost_gendev),472		 rport->state);473 474	if (rport->state == SRP_RPORT_LOST)475		return;476	if (delay > 0)477		queue_delayed_work(system_long_wq, &rport->reconnect_work,478				   1UL * delay * HZ);479	if ((fast_io_fail_tmo >= 0 || dev_loss_tmo >= 0) &&480	    srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) {481		pr_debug("%s new state: %d\n", dev_name(&shost->shost_gendev),482			 rport->state);483		scsi_block_targets(shost, &shost->shost_gendev);484		if (fast_io_fail_tmo >= 0)485			queue_delayed_work(system_long_wq,486					   &rport->fast_io_fail_work,487					   1UL * fast_io_fail_tmo * HZ);488		if (dev_loss_tmo >= 0)489			queue_delayed_work(system_long_wq,490					   &rport->dev_loss_work,491					   1UL * dev_loss_tmo * HZ);492	}493}494 495/**496 * srp_start_tl_fail_timers() - start the transport layer failure timers497 * @rport: SRP target port.498 *499 * Start the transport layer fast I/O failure and device loss timers. Do not500 * modify a timer that was already started.501 */502void srp_start_tl_fail_timers(struct srp_rport *rport)503{504	mutex_lock(&rport->mutex);505	__srp_start_tl_fail_timers(rport);506	mutex_unlock(&rport->mutex);507}508EXPORT_SYMBOL(srp_start_tl_fail_timers);509 510/**511 * srp_reconnect_rport() - reconnect to an SRP target port512 * @rport: SRP target port.513 *514 * Blocks SCSI command queueing before invoking reconnect() such that515 * queuecommand() won't be invoked concurrently with reconnect() from outside516 * the SCSI EH. This is important since a reconnect() implementation may517 * reallocate resources needed by queuecommand().518 *519 * Notes:520 * - This function neither waits until outstanding requests have finished nor521 *   tries to abort these. It is the responsibility of the reconnect()522 *   function to finish outstanding commands before reconnecting to the target523 *   port.524 * - It is the responsibility of the caller to ensure that the resources525 *   reallocated by the reconnect() function won't be used while this function526 *   is in progress. One possible strategy is to invoke this function from527 *   the context of the SCSI EH thread only. Another possible strategy is to528 *   lock the rport mutex inside each SCSI LLD callback that can be invoked by529 *   the SCSI EH (the scsi_host_template.eh_*() functions and also the530 *   scsi_host_template.queuecommand() function).531 */532int srp_reconnect_rport(struct srp_rport *rport)533{534	struct Scsi_Host *shost = rport_to_shost(rport);535	struct srp_internal *i = to_srp_internal(shost->transportt);536	struct scsi_device *sdev;537	int res;538 539	pr_debug("SCSI host %s\n", dev_name(&shost->shost_gendev));540 541	res = mutex_lock_interruptible(&rport->mutex);542	if (res)543		goto out;544	if (rport->state != SRP_RPORT_FAIL_FAST && rport->state != SRP_RPORT_LOST)545		/*546		 * sdev state must be SDEV_TRANSPORT_OFFLINE, transition547		 * to SDEV_BLOCK is illegal. Calling scsi_target_unblock()548		 * later is ok though, scsi_internal_device_unblock_nowait()549		 * treats SDEV_TRANSPORT_OFFLINE like SDEV_BLOCK.550		 */551		scsi_block_targets(shost, &shost->shost_gendev);552	res = rport->state != SRP_RPORT_LOST ? i->f->reconnect(rport) : -ENODEV;553	pr_debug("%s (state %d): transport.reconnect() returned %d\n",554		 dev_name(&shost->shost_gendev), rport->state, res);555	if (res == 0) {556		cancel_delayed_work(&rport->fast_io_fail_work);557		cancel_delayed_work(&rport->dev_loss_work);558 559		rport->failed_reconnects = 0;560		srp_rport_set_state(rport, SRP_RPORT_RUNNING);561		scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING);562		/*563		 * If the SCSI error handler has offlined one or more devices,564		 * invoking scsi_target_unblock() won't change the state of565		 * these devices into running so do that explicitly.566		 */567		shost_for_each_device(sdev, shost) {568			mutex_lock(&sdev->state_mutex);569			if (sdev->sdev_state == SDEV_OFFLINE)570				sdev->sdev_state = SDEV_RUNNING;571			mutex_unlock(&sdev->state_mutex);572		}573	} else if (rport->state == SRP_RPORT_RUNNING) {574		/*575		 * srp_reconnect_rport() has been invoked with fast_io_fail576		 * and dev_loss off. Mark the port as failed and start the TL577		 * failure timers if these had not yet been started.578		 */579		__rport_fail_io_fast(rport);580		__srp_start_tl_fail_timers(rport);581	} else if (rport->state != SRP_RPORT_BLOCKED) {582		scsi_target_unblock(&shost->shost_gendev,583				    SDEV_TRANSPORT_OFFLINE);584	}585	mutex_unlock(&rport->mutex);586 587out:588	return res;589}590EXPORT_SYMBOL(srp_reconnect_rport);591 592/**593 * srp_timed_out() - SRP transport intercept of the SCSI timeout EH594 * @scmd: SCSI command.595 *596 * If a timeout occurs while an rport is in the blocked state, ask the SCSI597 * EH to continue waiting (SCSI_EH_RESET_TIMER). Otherwise let the SCSI core598 * handle the timeout (SCSI_EH_NOT_HANDLED).599 *600 * Note: This function is called from soft-IRQ context and with the request601 * queue lock held.602 */603enum scsi_timeout_action srp_timed_out(struct scsi_cmnd *scmd)604{605	struct scsi_device *sdev = scmd->device;606	struct Scsi_Host *shost = sdev->host;607	struct srp_internal *i = to_srp_internal(shost->transportt);608	struct srp_rport *rport = shost_to_rport(shost);609 610	pr_debug("timeout for sdev %s\n", dev_name(&sdev->sdev_gendev));611	return rport && rport->fast_io_fail_tmo < 0 &&612		rport->dev_loss_tmo < 0 &&613		i->f->reset_timer_if_blocked && scsi_device_blocked(sdev) ?614		SCSI_EH_RESET_TIMER : SCSI_EH_NOT_HANDLED;615}616EXPORT_SYMBOL(srp_timed_out);617 618static void srp_rport_release(struct device *dev)619{620	struct srp_rport *rport = dev_to_rport(dev);621 622	put_device(dev->parent);623	kfree(rport);624}625 626static int scsi_is_srp_rport(const struct device *dev)627{628	return dev->release == srp_rport_release;629}630 631static int srp_rport_match(struct attribute_container *cont,632			   struct device *dev)633{634	struct Scsi_Host *shost;635	struct srp_internal *i;636 637	if (!scsi_is_srp_rport(dev))638		return 0;639 640	shost = dev_to_shost(dev->parent);641	if (!shost->transportt)642		return 0;643	if (shost->transportt->host_attrs.ac.class != &srp_host_class.class)644		return 0;645 646	i = to_srp_internal(shost->transportt);647	return &i->rport_attr_cont.ac == cont;648}649 650static int srp_host_match(struct attribute_container *cont, struct device *dev)651{652	struct Scsi_Host *shost;653	struct srp_internal *i;654 655	if (!scsi_is_host_device(dev))656		return 0;657 658	shost = dev_to_shost(dev);659	if (!shost->transportt)660		return 0;661	if (shost->transportt->host_attrs.ac.class != &srp_host_class.class)662		return 0;663 664	i = to_srp_internal(shost->transportt);665	return &i->t.host_attrs.ac == cont;666}667 668/**669 * srp_rport_get() - increment rport reference count670 * @rport: SRP target port.671 */672void srp_rport_get(struct srp_rport *rport)673{674	get_device(&rport->dev);675}676EXPORT_SYMBOL(srp_rport_get);677 678/**679 * srp_rport_put() - decrement rport reference count680 * @rport: SRP target port.681 */682void srp_rport_put(struct srp_rport *rport)683{684	put_device(&rport->dev);685}686EXPORT_SYMBOL(srp_rport_put);687 688/**689 * srp_rport_add - add a SRP remote port to the device hierarchy690 * @shost:	scsi host the remote port is connected to.691 * @ids:	The port id for the remote port.692 *693 * Publishes a port to the rest of the system.694 */695struct srp_rport *srp_rport_add(struct Scsi_Host *shost,696				struct srp_rport_identifiers *ids)697{698	struct srp_rport *rport;699	struct device *parent = &shost->shost_gendev;700	struct srp_internal *i = to_srp_internal(shost->transportt);701	int id, ret;702 703	rport = kzalloc(sizeof(*rport), GFP_KERNEL);704	if (!rport)705		return ERR_PTR(-ENOMEM);706 707	mutex_init(&rport->mutex);708 709	device_initialize(&rport->dev);710 711	rport->dev.parent = get_device(parent);712	rport->dev.release = srp_rport_release;713 714	memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id));715	rport->roles = ids->roles;716 717	if (i->f->reconnect)718		rport->reconnect_delay = i->f->reconnect_delay ?719			*i->f->reconnect_delay : 10;720	INIT_DELAYED_WORK(&rport->reconnect_work, srp_reconnect_work);721	rport->fast_io_fail_tmo = i->f->fast_io_fail_tmo ?722		*i->f->fast_io_fail_tmo : 15;723	rport->dev_loss_tmo = i->f->dev_loss_tmo ? *i->f->dev_loss_tmo : 60;724	INIT_DELAYED_WORK(&rport->fast_io_fail_work,725			  rport_fast_io_fail_timedout);726	INIT_DELAYED_WORK(&rport->dev_loss_work, rport_dev_loss_timedout);727 728	id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id);729	dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id);730 731	transport_setup_device(&rport->dev);732 733	ret = device_add(&rport->dev);734	if (ret) {735		transport_destroy_device(&rport->dev);736		put_device(&rport->dev);737		return ERR_PTR(ret);738	}739 740	transport_add_device(&rport->dev);741	transport_configure_device(&rport->dev);742 743	return rport;744}745EXPORT_SYMBOL_GPL(srp_rport_add);746 747/**748 * srp_rport_del  -  remove a SRP remote port749 * @rport:	SRP remote port to remove750 *751 * Removes the specified SRP remote port.752 */753void srp_rport_del(struct srp_rport *rport)754{755	struct device *dev = &rport->dev;756 757	transport_remove_device(dev);758	device_del(dev);759	transport_destroy_device(dev);760 761	put_device(dev);762}763EXPORT_SYMBOL_GPL(srp_rport_del);764 765static int do_srp_rport_del(struct device *dev, void *data)766{767	if (scsi_is_srp_rport(dev))768		srp_rport_del(dev_to_rport(dev));769	return 0;770}771 772/**773 * srp_remove_host  -  tear down a Scsi_Host's SRP data structures774 * @shost:	Scsi Host that is torn down775 *776 * Removes all SRP remote ports for a given Scsi_Host.777 * Must be called just before scsi_remove_host for SRP HBAs.778 */779void srp_remove_host(struct Scsi_Host *shost)780{781	device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del);782}783EXPORT_SYMBOL_GPL(srp_remove_host);784 785/**786 * srp_stop_rport_timers - stop the transport layer recovery timers787 * @rport: SRP remote port for which to stop the timers.788 *789 * Must be called after srp_remove_host() and scsi_remove_host(). The caller790 * must hold a reference on the rport (rport->dev) and on the SCSI host791 * (rport->dev.parent).792 */793void srp_stop_rport_timers(struct srp_rport *rport)794{795	mutex_lock(&rport->mutex);796	if (rport->state == SRP_RPORT_BLOCKED)797		__rport_fail_io_fast(rport);798	srp_rport_set_state(rport, SRP_RPORT_LOST);799	mutex_unlock(&rport->mutex);800 801	cancel_delayed_work_sync(&rport->reconnect_work);802	cancel_delayed_work_sync(&rport->fast_io_fail_work);803	cancel_delayed_work_sync(&rport->dev_loss_work);804}805EXPORT_SYMBOL_GPL(srp_stop_rport_timers);806 807/**808 * srp_attach_transport  -  instantiate SRP transport template809 * @ft:		SRP transport class function template810 */811struct scsi_transport_template *812srp_attach_transport(struct srp_function_template *ft)813{814	int count;815	struct srp_internal *i;816 817	i = kzalloc(sizeof(*i), GFP_KERNEL);818	if (!i)819		return NULL;820 821	i->t.host_size = sizeof(struct srp_host_attrs);822	i->t.host_attrs.ac.attrs = &i->host_attrs[0];823	i->t.host_attrs.ac.class = &srp_host_class.class;824	i->t.host_attrs.ac.match = srp_host_match;825	i->host_attrs[0] = NULL;826	transport_container_register(&i->t.host_attrs);827 828	i->rport_attr_cont.ac.attrs = &i->rport_attrs[0];829	i->rport_attr_cont.ac.class = &srp_rport_class.class;830	i->rport_attr_cont.ac.match = srp_rport_match;831 832	count = 0;833	i->rport_attrs[count++] = &dev_attr_port_id;834	i->rport_attrs[count++] = &dev_attr_roles;835	if (ft->has_rport_state) {836		i->rport_attrs[count++] = &dev_attr_state;837		i->rport_attrs[count++] = &dev_attr_fast_io_fail_tmo;838		i->rport_attrs[count++] = &dev_attr_dev_loss_tmo;839	}840	if (ft->reconnect) {841		i->rport_attrs[count++] = &dev_attr_reconnect_delay;842		i->rport_attrs[count++] = &dev_attr_failed_reconnects;843	}844	if (ft->rport_delete)845		i->rport_attrs[count++] = &dev_attr_delete;846	i->rport_attrs[count++] = NULL;847	BUG_ON(count > ARRAY_SIZE(i->rport_attrs));848 849	transport_container_register(&i->rport_attr_cont);850 851	i->f = ft;852 853	return &i->t;854}855EXPORT_SYMBOL_GPL(srp_attach_transport);856 857/**858 * srp_release_transport  -  release SRP transport template instance859 * @t:		transport template instance860 */861void srp_release_transport(struct scsi_transport_template *t)862{863	struct srp_internal *i = to_srp_internal(t);864 865	transport_container_unregister(&i->t.host_attrs);866	transport_container_unregister(&i->rport_attr_cont);867 868	kfree(i);869}870EXPORT_SYMBOL_GPL(srp_release_transport);871 872static __init int srp_transport_init(void)873{874	int ret;875 876	ret = transport_class_register(&srp_host_class);877	if (ret)878		return ret;879	ret = transport_class_register(&srp_rport_class);880	if (ret)881		goto unregister_host_class;882 883	return 0;884unregister_host_class:885	transport_class_unregister(&srp_host_class);886	return ret;887}888 889static void __exit srp_transport_exit(void)890{891	transport_class_unregister(&srp_host_class);892	transport_class_unregister(&srp_rport_class);893}894 895MODULE_AUTHOR("FUJITA Tomonori");896MODULE_DESCRIPTION("SRP Transport Attributes");897MODULE_LICENSE("GPL");898 899module_init(srp_transport_init);900module_exit(srp_transport_exit);901