brintos

brintos / linux-shallow public Read only

0
0
Text · 106.5 KiB · 5dfb464 Raw
3989 lines · c
1/*2 * Copyright (c) 2006 - 2009 Mellanox Technology Inc.  All rights reserved.3 * Copyright (C) 2008 - 2011 Bart Van Assche <bvanassche@acm.org>.4 *5 * This software is available to you under a choice of one of two6 * licenses.  You may choose to be licensed under the terms of the GNU7 * General Public License (GPL) Version 2, available from the file8 * COPYING in the main directory of this source tree, or the9 * OpenIB.org BSD license below:10 *11 *     Redistribution and use in source and binary forms, with or12 *     without modification, are permitted provided that the following13 *     conditions are met:14 *15 *      - Redistributions of source code must retain the above16 *        copyright notice, this list of conditions and the following17 *        disclaimer.18 *19 *      - Redistributions in binary form must reproduce the above20 *        copyright notice, this list of conditions and the following21 *        disclaimer in the documentation and/or other materials22 *        provided with the distribution.23 *24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE31 * SOFTWARE.32 *33 */34 35#include <linux/module.h>36#include <linux/init.h>37#include <linux/slab.h>38#include <linux/err.h>39#include <linux/ctype.h>40#include <linux/kthread.h>41#include <linux/string.h>42#include <linux/delay.h>43#include <linux/atomic.h>44#include <linux/inet.h>45#include <rdma/ib_cache.h>46#include <scsi/scsi_proto.h>47#include <scsi/scsi_tcq.h>48#include <target/target_core_base.h>49#include <target/target_core_fabric.h>50#include "ib_srpt.h"51 52/* Name of this kernel module. */53#define DRV_NAME		"ib_srpt"54 55#define SRPT_ID_STRING	"Linux SRP target"56 57#undef pr_fmt58#define pr_fmt(fmt) DRV_NAME " " fmt59 60MODULE_AUTHOR("Vu Pham and Bart Van Assche");61MODULE_DESCRIPTION("SCSI RDMA Protocol target driver");62MODULE_LICENSE("Dual BSD/GPL");63 64/*65 * Global Variables66 */67 68static u64 srpt_service_guid;69static DEFINE_SPINLOCK(srpt_dev_lock);	/* Protects srpt_dev_list. */70static LIST_HEAD(srpt_dev_list);	/* List of srpt_device structures. */71static DEFINE_MUTEX(srpt_mc_mutex);	/* Protects srpt_memory_caches. */72static DEFINE_XARRAY(srpt_memory_caches); /* See also srpt_memory_cache_entry */73 74static unsigned srp_max_req_size = DEFAULT_MAX_REQ_SIZE;75module_param(srp_max_req_size, int, 0444);76MODULE_PARM_DESC(srp_max_req_size,77		 "Maximum size of SRP request messages in bytes.");78 79static int srpt_srq_size = DEFAULT_SRPT_SRQ_SIZE;80module_param(srpt_srq_size, int, 0444);81MODULE_PARM_DESC(srpt_srq_size,82		 "Shared receive queue (SRQ) size.");83 84static int srpt_set_u64_x(const char *buffer, const struct kernel_param *kp)85{86	return kstrtou64(buffer, 16, (u64 *)kp->arg);87}88static int srpt_get_u64_x(char *buffer, const struct kernel_param *kp)89{90	return sprintf(buffer, "0x%016llx\n", *(u64 *)kp->arg);91}92module_param_call(srpt_service_guid, srpt_set_u64_x, srpt_get_u64_x,93		  &srpt_service_guid, 0444);94MODULE_PARM_DESC(srpt_service_guid,95		 "Using this value for ioc_guid, id_ext, and cm_listen_id instead of using the node_guid of the first HCA.");96 97static struct ib_client srpt_client;98/* Protects both rdma_cm_port and rdma_cm_id. */99static DEFINE_MUTEX(rdma_cm_mutex);100/* Port number RDMA/CM will bind to. */101static u16 rdma_cm_port;102static struct rdma_cm_id *rdma_cm_id;103static void srpt_release_cmd(struct se_cmd *se_cmd);104static void srpt_free_ch(struct kref *kref);105static int srpt_queue_status(struct se_cmd *cmd);106static void srpt_recv_done(struct ib_cq *cq, struct ib_wc *wc);107static void srpt_send_done(struct ib_cq *cq, struct ib_wc *wc);108static void srpt_process_wait_list(struct srpt_rdma_ch *ch);109 110/* Type of the entries in srpt_memory_caches. */111struct srpt_memory_cache_entry {112	refcount_t ref;113	struct kmem_cache *c;114};115 116static struct kmem_cache *srpt_cache_get(unsigned int object_size)117{118	struct srpt_memory_cache_entry *e;119	char name[32];120	void *res;121 122	guard(mutex)(&srpt_mc_mutex);123	e = xa_load(&srpt_memory_caches, object_size);124	if (e) {125		refcount_inc(&e->ref);126		return e->c;127	}128	snprintf(name, sizeof(name), "srpt-%u", object_size);129	e = kmalloc(sizeof(*e), GFP_KERNEL);130	if (!e)131		return NULL;132	refcount_set(&e->ref, 1);133	e->c = kmem_cache_create(name, object_size, /*align=*/512, 0, NULL);134	if (!e->c)135		goto free_entry;136	res = xa_store(&srpt_memory_caches, object_size, e, GFP_KERNEL);137	if (xa_is_err(res))138		goto destroy_cache;139	return e->c;140 141destroy_cache:142	kmem_cache_destroy(e->c);143 144free_entry:145	kfree(e);146	return NULL;147}148 149static void srpt_cache_put(struct kmem_cache *c)150{151	struct srpt_memory_cache_entry *e = NULL;152	unsigned long object_size;153 154	guard(mutex)(&srpt_mc_mutex);155	xa_for_each(&srpt_memory_caches, object_size, e)156		if (e->c == c)157			break;158	if (WARN_ON_ONCE(!e))159		return;160	if (!refcount_dec_and_test(&e->ref))161		return;162	WARN_ON_ONCE(xa_erase(&srpt_memory_caches, object_size) != e);163	kmem_cache_destroy(e->c);164	kfree(e);165}166 167/*168 * The only allowed channel state changes are those that change the channel169 * state into a state with a higher numerical value. Hence the new > prev test.170 */171static bool srpt_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state new)172{173	unsigned long flags;174	enum rdma_ch_state prev;175	bool changed = false;176 177	spin_lock_irqsave(&ch->spinlock, flags);178	prev = ch->state;179	if (new > prev) {180		ch->state = new;181		changed = true;182	}183	spin_unlock_irqrestore(&ch->spinlock, flags);184 185	return changed;186}187 188/**189 * srpt_event_handler - asynchronous IB event callback function190 * @handler: IB event handler registered by ib_register_event_handler().191 * @event: Description of the event that occurred.192 *193 * Callback function called by the InfiniBand core when an asynchronous IB194 * event occurs. This callback may occur in interrupt context. See also195 * section 11.5.2, Set Asynchronous Event Handler in the InfiniBand196 * Architecture Specification.197 */198static void srpt_event_handler(struct ib_event_handler *handler,199			       struct ib_event *event)200{201	struct srpt_device *sdev =202		container_of(handler, struct srpt_device, event_handler);203	struct srpt_port *sport;204	u8 port_num;205 206	pr_debug("ASYNC event= %d on device= %s\n", event->event,207		 dev_name(&sdev->device->dev));208 209	switch (event->event) {210	case IB_EVENT_PORT_ERR:211		port_num = event->element.port_num - 1;212		if (port_num < sdev->device->phys_port_cnt) {213			sport = &sdev->port[port_num];214			sport->lid = 0;215			sport->sm_lid = 0;216		} else {217			WARN(true, "event %d: port_num %d out of range 1..%d\n",218			     event->event, port_num + 1,219			     sdev->device->phys_port_cnt);220		}221		break;222	case IB_EVENT_PORT_ACTIVE:223	case IB_EVENT_LID_CHANGE:224	case IB_EVENT_PKEY_CHANGE:225	case IB_EVENT_SM_CHANGE:226	case IB_EVENT_CLIENT_REREGISTER:227	case IB_EVENT_GID_CHANGE:228		/* Refresh port data asynchronously. */229		port_num = event->element.port_num - 1;230		if (port_num < sdev->device->phys_port_cnt) {231			sport = &sdev->port[port_num];232			if (!sport->lid && !sport->sm_lid)233				schedule_work(&sport->work);234		} else {235			WARN(true, "event %d: port_num %d out of range 1..%d\n",236			     event->event, port_num + 1,237			     sdev->device->phys_port_cnt);238		}239		break;240	default:241		pr_err("received unrecognized IB event %d\n", event->event);242		break;243	}244}245 246/**247 * srpt_srq_event - SRQ event callback function248 * @event: Description of the event that occurred.249 * @ctx: Context pointer specified at SRQ creation time.250 */251static void srpt_srq_event(struct ib_event *event, void *ctx)252{253	pr_debug("SRQ event %d\n", event->event);254}255 256static const char *get_ch_state_name(enum rdma_ch_state s)257{258	switch (s) {259	case CH_CONNECTING:260		return "connecting";261	case CH_LIVE:262		return "live";263	case CH_DISCONNECTING:264		return "disconnecting";265	case CH_DRAINING:266		return "draining";267	case CH_DISCONNECTED:268		return "disconnected";269	}270	return "???";271}272 273/**274 * srpt_qp_event - QP event callback function275 * @event: Description of the event that occurred.276 * @ptr: SRPT RDMA channel.277 */278static void srpt_qp_event(struct ib_event *event, void *ptr)279{280	struct srpt_rdma_ch *ch = ptr;281 282	pr_debug("QP event %d on ch=%p sess_name=%s-%d state=%s\n",283		 event->event, ch, ch->sess_name, ch->qp->qp_num,284		 get_ch_state_name(ch->state));285 286	switch (event->event) {287	case IB_EVENT_COMM_EST:288		if (ch->using_rdma_cm)289			rdma_notify(ch->rdma_cm.cm_id, event->event);290		else291			ib_cm_notify(ch->ib_cm.cm_id, event->event);292		break;293	case IB_EVENT_QP_LAST_WQE_REACHED:294		pr_debug("%s-%d, state %s: received Last WQE event.\n",295			 ch->sess_name, ch->qp->qp_num,296			 get_ch_state_name(ch->state));297		break;298	default:299		pr_err("received unrecognized IB QP event %d\n", event->event);300		break;301	}302}303 304/**305 * srpt_set_ioc - initialize a IOUnitInfo structure306 * @c_list: controller list.307 * @slot: one-based slot number.308 * @value: four-bit value.309 *310 * Copies the lowest four bits of value in element slot of the array of four311 * bit elements called c_list (controller list). The index slot is one-based.312 */313static void srpt_set_ioc(u8 *c_list, u32 slot, u8 value)314{315	u16 id;316	u8 tmp;317 318	id = (slot - 1) / 2;319	if (slot & 0x1) {320		tmp = c_list[id] & 0xf;321		c_list[id] = (value << 4) | tmp;322	} else {323		tmp = c_list[id] & 0xf0;324		c_list[id] = (value & 0xf) | tmp;325	}326}327 328/**329 * srpt_get_class_port_info - copy ClassPortInfo to a management datagram330 * @mad: Datagram that will be sent as response to DM_ATTR_CLASS_PORT_INFO.331 *332 * See also section 16.3.3.1 ClassPortInfo in the InfiniBand Architecture333 * Specification.334 */335static void srpt_get_class_port_info(struct ib_dm_mad *mad)336{337	struct ib_class_port_info *cif;338 339	cif = (struct ib_class_port_info *)mad->data;340	memset(cif, 0, sizeof(*cif));341	cif->base_version = 1;342	cif->class_version = 1;343 344	ib_set_cpi_resp_time(cif, 20);345	mad->mad_hdr.status = 0;346}347 348/**349 * srpt_get_iou - write IOUnitInfo to a management datagram350 * @mad: Datagram that will be sent as response to DM_ATTR_IOU_INFO.351 *352 * See also section 16.3.3.3 IOUnitInfo in the InfiniBand Architecture353 * Specification. See also section B.7, table B.6 in the SRP r16a document.354 */355static void srpt_get_iou(struct ib_dm_mad *mad)356{357	struct ib_dm_iou_info *ioui;358	u8 slot;359	int i;360 361	ioui = (struct ib_dm_iou_info *)mad->data;362	ioui->change_id = cpu_to_be16(1);363	ioui->max_controllers = 16;364 365	/* set present for slot 1 and empty for the rest */366	srpt_set_ioc(ioui->controller_list, 1, 1);367	for (i = 1, slot = 2; i < 16; i++, slot++)368		srpt_set_ioc(ioui->controller_list, slot, 0);369 370	mad->mad_hdr.status = 0;371}372 373/**374 * srpt_get_ioc - write IOControllerprofile to a management datagram375 * @sport: HCA port through which the MAD has been received.376 * @slot: Slot number specified in DM_ATTR_IOC_PROFILE query.377 * @mad: Datagram that will be sent as response to DM_ATTR_IOC_PROFILE.378 *379 * See also section 16.3.3.4 IOControllerProfile in the InfiniBand380 * Architecture Specification. See also section B.7, table B.7 in the SRP381 * r16a document.382 */383static void srpt_get_ioc(struct srpt_port *sport, u32 slot,384			 struct ib_dm_mad *mad)385{386	struct srpt_device *sdev = sport->sdev;387	struct ib_dm_ioc_profile *iocp;388	int send_queue_depth;389 390	iocp = (struct ib_dm_ioc_profile *)mad->data;391 392	if (!slot || slot > 16) {393		mad->mad_hdr.status394			= cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);395		return;396	}397 398	if (slot > 2) {399		mad->mad_hdr.status400			= cpu_to_be16(DM_MAD_STATUS_NO_IOC);401		return;402	}403 404	if (sdev->use_srq)405		send_queue_depth = sdev->srq_size;406	else407		send_queue_depth = min(MAX_SRPT_RQ_SIZE,408				       sdev->device->attrs.max_qp_wr);409 410	memset(iocp, 0, sizeof(*iocp));411	strcpy(iocp->id_string, SRPT_ID_STRING);412	iocp->guid = cpu_to_be64(srpt_service_guid);413	iocp->vendor_id = cpu_to_be32(sdev->device->attrs.vendor_id);414	iocp->device_id = cpu_to_be32(sdev->device->attrs.vendor_part_id);415	iocp->device_version = cpu_to_be16(sdev->device->attrs.hw_ver);416	iocp->subsys_vendor_id = cpu_to_be32(sdev->device->attrs.vendor_id);417	iocp->subsys_device_id = 0x0;418	iocp->io_class = cpu_to_be16(SRP_REV16A_IB_IO_CLASS);419	iocp->io_subclass = cpu_to_be16(SRP_IO_SUBCLASS);420	iocp->protocol = cpu_to_be16(SRP_PROTOCOL);421	iocp->protocol_version = cpu_to_be16(SRP_PROTOCOL_VERSION);422	iocp->send_queue_depth = cpu_to_be16(send_queue_depth);423	iocp->rdma_read_depth = 4;424	iocp->send_size = cpu_to_be32(srp_max_req_size);425	iocp->rdma_size = cpu_to_be32(min(sport->port_attrib.srp_max_rdma_size,426					  1U << 24));427	iocp->num_svc_entries = 1;428	iocp->op_cap_mask = SRP_SEND_TO_IOC | SRP_SEND_FROM_IOC |429		SRP_RDMA_READ_FROM_IOC | SRP_RDMA_WRITE_FROM_IOC;430 431	mad->mad_hdr.status = 0;432}433 434/**435 * srpt_get_svc_entries - write ServiceEntries to a management datagram436 * @ioc_guid: I/O controller GUID to use in reply.437 * @slot: I/O controller number.438 * @hi: End of the range of service entries to be specified in the reply.439 * @lo: Start of the range of service entries to be specified in the reply..440 * @mad: Datagram that will be sent as response to DM_ATTR_SVC_ENTRIES.441 *442 * See also section 16.3.3.5 ServiceEntries in the InfiniBand Architecture443 * Specification. See also section B.7, table B.8 in the SRP r16a document.444 */445static void srpt_get_svc_entries(u64 ioc_guid,446				 u16 slot, u8 hi, u8 lo, struct ib_dm_mad *mad)447{448	struct ib_dm_svc_entries *svc_entries;449 450	WARN_ON(!ioc_guid);451 452	if (!slot || slot > 16) {453		mad->mad_hdr.status454			= cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);455		return;456	}457 458	if (slot > 2 || lo > hi || hi > 1) {459		mad->mad_hdr.status460			= cpu_to_be16(DM_MAD_STATUS_NO_IOC);461		return;462	}463 464	svc_entries = (struct ib_dm_svc_entries *)mad->data;465	memset(svc_entries, 0, sizeof(*svc_entries));466	svc_entries->service_entries[0].id = cpu_to_be64(ioc_guid);467	snprintf(svc_entries->service_entries[0].name,468		 sizeof(svc_entries->service_entries[0].name),469		 "%s%016llx",470		 SRP_SERVICE_NAME_PREFIX,471		 ioc_guid);472 473	mad->mad_hdr.status = 0;474}475 476/**477 * srpt_mgmt_method_get - process a received management datagram478 * @sp:      HCA port through which the MAD has been received.479 * @rq_mad:  received MAD.480 * @rsp_mad: response MAD.481 */482static void srpt_mgmt_method_get(struct srpt_port *sp, struct ib_mad *rq_mad,483				 struct ib_dm_mad *rsp_mad)484{485	u16 attr_id;486	u32 slot;487	u8 hi, lo;488 489	attr_id = be16_to_cpu(rq_mad->mad_hdr.attr_id);490	switch (attr_id) {491	case DM_ATTR_CLASS_PORT_INFO:492		srpt_get_class_port_info(rsp_mad);493		break;494	case DM_ATTR_IOU_INFO:495		srpt_get_iou(rsp_mad);496		break;497	case DM_ATTR_IOC_PROFILE:498		slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod);499		srpt_get_ioc(sp, slot, rsp_mad);500		break;501	case DM_ATTR_SVC_ENTRIES:502		slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod);503		hi = (u8) ((slot >> 8) & 0xff);504		lo = (u8) (slot & 0xff);505		slot = (u16) ((slot >> 16) & 0xffff);506		srpt_get_svc_entries(srpt_service_guid,507				     slot, hi, lo, rsp_mad);508		break;509	default:510		rsp_mad->mad_hdr.status =511		    cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);512		break;513	}514}515 516/**517 * srpt_mad_send_handler - MAD send completion callback518 * @mad_agent: Return value of ib_register_mad_agent().519 * @mad_wc: Work completion reporting that the MAD has been sent.520 */521static void srpt_mad_send_handler(struct ib_mad_agent *mad_agent,522				  struct ib_mad_send_wc *mad_wc)523{524	rdma_destroy_ah(mad_wc->send_buf->ah, RDMA_DESTROY_AH_SLEEPABLE);525	ib_free_send_mad(mad_wc->send_buf);526}527 528/**529 * srpt_mad_recv_handler - MAD reception callback function530 * @mad_agent: Return value of ib_register_mad_agent().531 * @send_buf: Not used.532 * @mad_wc: Work completion reporting that a MAD has been received.533 */534static void srpt_mad_recv_handler(struct ib_mad_agent *mad_agent,535				  struct ib_mad_send_buf *send_buf,536				  struct ib_mad_recv_wc *mad_wc)537{538	struct srpt_port *sport = (struct srpt_port *)mad_agent->context;539	struct ib_ah *ah;540	struct ib_mad_send_buf *rsp;541	struct ib_dm_mad *dm_mad;542 543	if (!mad_wc || !mad_wc->recv_buf.mad)544		return;545 546	ah = ib_create_ah_from_wc(mad_agent->qp->pd, mad_wc->wc,547				  mad_wc->recv_buf.grh, mad_agent->port_num);548	if (IS_ERR(ah))549		goto err;550 551	BUILD_BUG_ON(offsetof(struct ib_dm_mad, data) != IB_MGMT_DEVICE_HDR);552 553	rsp = ib_create_send_mad(mad_agent, mad_wc->wc->src_qp,554				 mad_wc->wc->pkey_index, 0,555				 IB_MGMT_DEVICE_HDR, IB_MGMT_DEVICE_DATA,556				 GFP_KERNEL,557				 IB_MGMT_BASE_VERSION);558	if (IS_ERR(rsp))559		goto err_rsp;560 561	rsp->ah = ah;562 563	dm_mad = rsp->mad;564	memcpy(dm_mad, mad_wc->recv_buf.mad, sizeof(*dm_mad));565	dm_mad->mad_hdr.method = IB_MGMT_METHOD_GET_RESP;566	dm_mad->mad_hdr.status = 0;567 568	switch (mad_wc->recv_buf.mad->mad_hdr.method) {569	case IB_MGMT_METHOD_GET:570		srpt_mgmt_method_get(sport, mad_wc->recv_buf.mad, dm_mad);571		break;572	case IB_MGMT_METHOD_SET:573		dm_mad->mad_hdr.status =574		    cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);575		break;576	default:577		dm_mad->mad_hdr.status =578		    cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD);579		break;580	}581 582	if (!ib_post_send_mad(rsp, NULL)) {583		ib_free_recv_mad(mad_wc);584		/* will destroy_ah & free_send_mad in send completion */585		return;586	}587 588	ib_free_send_mad(rsp);589 590err_rsp:591	rdma_destroy_ah(ah, RDMA_DESTROY_AH_SLEEPABLE);592err:593	ib_free_recv_mad(mad_wc);594}595 596static int srpt_format_guid(char *buf, unsigned int size, const __be64 *guid)597{598	const __be16 *g = (const __be16 *)guid;599 600	return snprintf(buf, size, "%04x:%04x:%04x:%04x",601			be16_to_cpu(g[0]), be16_to_cpu(g[1]),602			be16_to_cpu(g[2]), be16_to_cpu(g[3]));603}604 605/**606 * srpt_refresh_port - configure a HCA port607 * @sport: SRPT HCA port.608 *609 * Enable InfiniBand management datagram processing, update the cached sm_lid,610 * lid and gid values, and register a callback function for processing MADs611 * on the specified port.612 *613 * Note: It is safe to call this function more than once for the same port.614 */615static int srpt_refresh_port(struct srpt_port *sport)616{617	struct ib_mad_agent *mad_agent;618	struct ib_mad_reg_req reg_req;619	struct ib_port_modify port_modify;620	struct ib_port_attr port_attr;621	int ret;622 623	ret = ib_query_port(sport->sdev->device, sport->port, &port_attr);624	if (ret)625		return ret;626 627	sport->sm_lid = port_attr.sm_lid;628	sport->lid = port_attr.lid;629 630	ret = rdma_query_gid(sport->sdev->device, sport->port, 0, &sport->gid);631	if (ret)632		return ret;633 634	srpt_format_guid(sport->guid_name, ARRAY_SIZE(sport->guid_name),635			 &sport->gid.global.interface_id);636	snprintf(sport->gid_name, ARRAY_SIZE(sport->gid_name),637		 "0x%016llx%016llx",638		 be64_to_cpu(sport->gid.global.subnet_prefix),639		 be64_to_cpu(sport->gid.global.interface_id));640 641	if (rdma_protocol_iwarp(sport->sdev->device, sport->port))642		return 0;643 644	memset(&port_modify, 0, sizeof(port_modify));645	port_modify.set_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP;646	port_modify.clr_port_cap_mask = 0;647 648	ret = ib_modify_port(sport->sdev->device, sport->port, 0, &port_modify);649	if (ret) {650		pr_warn("%s-%d: enabling device management failed (%d). Note: this is expected if SR-IOV is enabled.\n",651			dev_name(&sport->sdev->device->dev), sport->port, ret);652		return 0;653	}654 655	if (!sport->mad_agent) {656		memset(&reg_req, 0, sizeof(reg_req));657		reg_req.mgmt_class = IB_MGMT_CLASS_DEVICE_MGMT;658		reg_req.mgmt_class_version = IB_MGMT_BASE_VERSION;659		set_bit(IB_MGMT_METHOD_GET, reg_req.method_mask);660		set_bit(IB_MGMT_METHOD_SET, reg_req.method_mask);661 662		mad_agent = ib_register_mad_agent(sport->sdev->device,663						  sport->port,664						  IB_QPT_GSI,665						  &reg_req, 0,666						  srpt_mad_send_handler,667						  srpt_mad_recv_handler,668						  sport, 0);669		if (IS_ERR(mad_agent)) {670			pr_err("%s-%d: MAD agent registration failed (%ld). Note: this is expected if SR-IOV is enabled.\n",671			       dev_name(&sport->sdev->device->dev), sport->port,672			       PTR_ERR(mad_agent));673			sport->mad_agent = NULL;674			memset(&port_modify, 0, sizeof(port_modify));675			port_modify.clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP;676			ib_modify_port(sport->sdev->device, sport->port, 0,677				       &port_modify);678			return 0;679		}680 681		sport->mad_agent = mad_agent;682	}683 684	return 0;685}686 687/**688 * srpt_unregister_mad_agent - unregister MAD callback functions689 * @sdev: SRPT HCA pointer.690 * @port_cnt: number of ports with registered MAD691 *692 * Note: It is safe to call this function more than once for the same device.693 */694static void srpt_unregister_mad_agent(struct srpt_device *sdev, int port_cnt)695{696	struct ib_port_modify port_modify = {697		.clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP,698	};699	struct srpt_port *sport;700	int i;701 702	for (i = 1; i <= port_cnt; i++) {703		sport = &sdev->port[i - 1];704		WARN_ON(sport->port != i);705		if (sport->mad_agent) {706			ib_modify_port(sdev->device, i, 0, &port_modify);707			ib_unregister_mad_agent(sport->mad_agent);708			sport->mad_agent = NULL;709		}710	}711}712 713/**714 * srpt_alloc_ioctx - allocate a SRPT I/O context structure715 * @sdev: SRPT HCA pointer.716 * @ioctx_size: I/O context size.717 * @buf_cache: I/O buffer cache.718 * @dir: DMA data direction.719 */720static struct srpt_ioctx *srpt_alloc_ioctx(struct srpt_device *sdev,721					   int ioctx_size,722					   struct kmem_cache *buf_cache,723					   enum dma_data_direction dir)724{725	struct srpt_ioctx *ioctx;726 727	ioctx = kzalloc(ioctx_size, GFP_KERNEL);728	if (!ioctx)729		goto err;730 731	ioctx->buf = kmem_cache_alloc(buf_cache, GFP_KERNEL);732	if (!ioctx->buf)733		goto err_free_ioctx;734 735	ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf,736				       kmem_cache_size(buf_cache), dir);737	if (ib_dma_mapping_error(sdev->device, ioctx->dma))738		goto err_free_buf;739 740	return ioctx;741 742err_free_buf:743	kmem_cache_free(buf_cache, ioctx->buf);744err_free_ioctx:745	kfree(ioctx);746err:747	return NULL;748}749 750/**751 * srpt_free_ioctx - free a SRPT I/O context structure752 * @sdev: SRPT HCA pointer.753 * @ioctx: I/O context pointer.754 * @buf_cache: I/O buffer cache.755 * @dir: DMA data direction.756 */757static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx,758			    struct kmem_cache *buf_cache,759			    enum dma_data_direction dir)760{761	if (!ioctx)762		return;763 764	ib_dma_unmap_single(sdev->device, ioctx->dma,765			    kmem_cache_size(buf_cache), dir);766	kmem_cache_free(buf_cache, ioctx->buf);767	kfree(ioctx);768}769 770/**771 * srpt_alloc_ioctx_ring - allocate a ring of SRPT I/O context structures772 * @sdev:       Device to allocate the I/O context ring for.773 * @ring_size:  Number of elements in the I/O context ring.774 * @ioctx_size: I/O context size.775 * @buf_cache:  I/O buffer cache.776 * @alignment_offset: Offset in each ring buffer at which the SRP information777 *		unit starts.778 * @dir:        DMA data direction.779 */780static struct srpt_ioctx **srpt_alloc_ioctx_ring(struct srpt_device *sdev,781				int ring_size, int ioctx_size,782				struct kmem_cache *buf_cache,783				int alignment_offset,784				enum dma_data_direction dir)785{786	struct srpt_ioctx **ring;787	int i;788 789	WARN_ON(ioctx_size != sizeof(struct srpt_recv_ioctx) &&790		ioctx_size != sizeof(struct srpt_send_ioctx));791 792	ring = kvmalloc_array(ring_size, sizeof(ring[0]), GFP_KERNEL);793	if (!ring)794		goto out;795	for (i = 0; i < ring_size; ++i) {796		ring[i] = srpt_alloc_ioctx(sdev, ioctx_size, buf_cache, dir);797		if (!ring[i])798			goto err;799		ring[i]->index = i;800		ring[i]->offset = alignment_offset;801	}802	goto out;803 804err:805	while (--i >= 0)806		srpt_free_ioctx(sdev, ring[i], buf_cache, dir);807	kvfree(ring);808	ring = NULL;809out:810	return ring;811}812 813/**814 * srpt_free_ioctx_ring - free the ring of SRPT I/O context structures815 * @ioctx_ring: I/O context ring to be freed.816 * @sdev: SRPT HCA pointer.817 * @ring_size: Number of ring elements.818 * @buf_cache: I/O buffer cache.819 * @dir: DMA data direction.820 */821static void srpt_free_ioctx_ring(struct srpt_ioctx **ioctx_ring,822				 struct srpt_device *sdev, int ring_size,823				 struct kmem_cache *buf_cache,824				 enum dma_data_direction dir)825{826	int i;827 828	if (!ioctx_ring)829		return;830 831	for (i = 0; i < ring_size; ++i)832		srpt_free_ioctx(sdev, ioctx_ring[i], buf_cache, dir);833	kvfree(ioctx_ring);834}835 836/**837 * srpt_set_cmd_state - set the state of a SCSI command838 * @ioctx: Send I/O context.839 * @new: New I/O context state.840 *841 * Does not modify the state of aborted commands. Returns the previous command842 * state.843 */844static enum srpt_command_state srpt_set_cmd_state(struct srpt_send_ioctx *ioctx,845						  enum srpt_command_state new)846{847	enum srpt_command_state previous;848 849	previous = ioctx->state;850	if (previous != SRPT_STATE_DONE)851		ioctx->state = new;852 853	return previous;854}855 856/**857 * srpt_test_and_set_cmd_state - test and set the state of a command858 * @ioctx: Send I/O context.859 * @old: Current I/O context state.860 * @new: New I/O context state.861 *862 * Returns true if and only if the previous command state was equal to 'old'.863 */864static bool srpt_test_and_set_cmd_state(struct srpt_send_ioctx *ioctx,865					enum srpt_command_state old,866					enum srpt_command_state new)867{868	enum srpt_command_state previous;869 870	WARN_ON(!ioctx);871	WARN_ON(old == SRPT_STATE_DONE);872	WARN_ON(new == SRPT_STATE_NEW);873 874	previous = ioctx->state;875	if (previous == old)876		ioctx->state = new;877 878	return previous == old;879}880 881/**882 * srpt_post_recv - post an IB receive request883 * @sdev: SRPT HCA pointer.884 * @ch: SRPT RDMA channel.885 * @ioctx: Receive I/O context pointer.886 */887static int srpt_post_recv(struct srpt_device *sdev, struct srpt_rdma_ch *ch,888			  struct srpt_recv_ioctx *ioctx)889{890	struct ib_sge list;891	struct ib_recv_wr wr;892 893	BUG_ON(!sdev);894	list.addr = ioctx->ioctx.dma + ioctx->ioctx.offset;895	list.length = srp_max_req_size;896	list.lkey = sdev->lkey;897 898	ioctx->ioctx.cqe.done = srpt_recv_done;899	wr.wr_cqe = &ioctx->ioctx.cqe;900	wr.next = NULL;901	wr.sg_list = &list;902	wr.num_sge = 1;903 904	if (sdev->use_srq)905		return ib_post_srq_recv(sdev->srq, &wr, NULL);906	else907		return ib_post_recv(ch->qp, &wr, NULL);908}909 910/**911 * srpt_zerolength_write - perform a zero-length RDMA write912 * @ch: SRPT RDMA channel.913 *914 * A quote from the InfiniBand specification: C9-88: For an HCA responder915 * using Reliable Connection service, for each zero-length RDMA READ or WRITE916 * request, the R_Key shall not be validated, even if the request includes917 * Immediate data.918 */919static int srpt_zerolength_write(struct srpt_rdma_ch *ch)920{921	struct ib_rdma_wr wr = {922		.wr = {923			.next		= NULL,924			{ .wr_cqe	= &ch->zw_cqe, },925			.opcode		= IB_WR_RDMA_WRITE,926			.send_flags	= IB_SEND_SIGNALED,927		}928	};929 930	pr_debug("%s-%d: queued zerolength write\n", ch->sess_name,931		 ch->qp->qp_num);932 933	return ib_post_send(ch->qp, &wr.wr, NULL);934}935 936static void srpt_zerolength_write_done(struct ib_cq *cq, struct ib_wc *wc)937{938	struct srpt_rdma_ch *ch = wc->qp->qp_context;939 940	pr_debug("%s-%d wc->status %d\n", ch->sess_name, ch->qp->qp_num,941		 wc->status);942 943	if (wc->status == IB_WC_SUCCESS) {944		srpt_process_wait_list(ch);945	} else {946		if (srpt_set_ch_state(ch, CH_DISCONNECTED))947			schedule_work(&ch->release_work);948		else949			pr_debug("%s-%d: already disconnected.\n",950				 ch->sess_name, ch->qp->qp_num);951	}952}953 954static int srpt_alloc_rw_ctxs(struct srpt_send_ioctx *ioctx,955		struct srp_direct_buf *db, int nbufs, struct scatterlist **sg,956		unsigned *sg_cnt)957{958	enum dma_data_direction dir = target_reverse_dma_direction(&ioctx->cmd);959	struct srpt_rdma_ch *ch = ioctx->ch;960	struct scatterlist *prev = NULL;961	unsigned prev_nents;962	int ret, i;963 964	if (nbufs == 1) {965		ioctx->rw_ctxs = &ioctx->s_rw_ctx;966	} else {967		ioctx->rw_ctxs = kmalloc_array(nbufs, sizeof(*ioctx->rw_ctxs),968			GFP_KERNEL);969		if (!ioctx->rw_ctxs)970			return -ENOMEM;971	}972 973	for (i = ioctx->n_rw_ctx; i < nbufs; i++, db++) {974		struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i];975		u64 remote_addr = be64_to_cpu(db->va);976		u32 size = be32_to_cpu(db->len);977		u32 rkey = be32_to_cpu(db->key);978 979		ret = target_alloc_sgl(&ctx->sg, &ctx->nents, size, false,980				i < nbufs - 1);981		if (ret)982			goto unwind;983 984		ret = rdma_rw_ctx_init(&ctx->rw, ch->qp, ch->sport->port,985				ctx->sg, ctx->nents, 0, remote_addr, rkey, dir);986		if (ret < 0) {987			target_free_sgl(ctx->sg, ctx->nents);988			goto unwind;989		}990 991		ioctx->n_rdma += ret;992		ioctx->n_rw_ctx++;993 994		if (prev) {995			sg_unmark_end(&prev[prev_nents - 1]);996			sg_chain(prev, prev_nents + 1, ctx->sg);997		} else {998			*sg = ctx->sg;999		}1000 1001		prev = ctx->sg;1002		prev_nents = ctx->nents;1003 1004		*sg_cnt += ctx->nents;1005	}1006 1007	return 0;1008 1009unwind:1010	while (--i >= 0) {1011		struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i];1012 1013		rdma_rw_ctx_destroy(&ctx->rw, ch->qp, ch->sport->port,1014				ctx->sg, ctx->nents, dir);1015		target_free_sgl(ctx->sg, ctx->nents);1016	}1017	if (ioctx->rw_ctxs != &ioctx->s_rw_ctx)1018		kfree(ioctx->rw_ctxs);1019	return ret;1020}1021 1022static void srpt_free_rw_ctxs(struct srpt_rdma_ch *ch,1023				    struct srpt_send_ioctx *ioctx)1024{1025	enum dma_data_direction dir = target_reverse_dma_direction(&ioctx->cmd);1026	int i;1027 1028	for (i = 0; i < ioctx->n_rw_ctx; i++) {1029		struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i];1030 1031		rdma_rw_ctx_destroy(&ctx->rw, ch->qp, ch->sport->port,1032				ctx->sg, ctx->nents, dir);1033		target_free_sgl(ctx->sg, ctx->nents);1034	}1035 1036	if (ioctx->rw_ctxs != &ioctx->s_rw_ctx)1037		kfree(ioctx->rw_ctxs);1038}1039 1040static inline void *srpt_get_desc_buf(struct srp_cmd *srp_cmd)1041{1042	/*1043	 * The pointer computations below will only be compiled correctly1044	 * if srp_cmd::add_data is declared as s8*, u8*, s8[] or u8[], so check1045	 * whether srp_cmd::add_data has been declared as a byte pointer.1046	 */1047	BUILD_BUG_ON(!__same_type(srp_cmd->add_data[0], (s8)0) &&1048		     !__same_type(srp_cmd->add_data[0], (u8)0));1049 1050	/*1051	 * According to the SRP spec, the lower two bits of the 'ADDITIONAL1052	 * CDB LENGTH' field are reserved and the size in bytes of this field1053	 * is four times the value specified in bits 3..7. Hence the "& ~3".1054	 */1055	return srp_cmd->add_data + (srp_cmd->add_cdb_len & ~3);1056}1057 1058/**1059 * srpt_get_desc_tbl - parse the data descriptors of a SRP_CMD request1060 * @recv_ioctx: I/O context associated with the received command @srp_cmd.1061 * @ioctx: I/O context that will be used for responding to the initiator.1062 * @srp_cmd: Pointer to the SRP_CMD request data.1063 * @dir: Pointer to the variable to which the transfer direction will be1064 *   written.1065 * @sg: [out] scatterlist for the parsed SRP_CMD.1066 * @sg_cnt: [out] length of @sg.1067 * @data_len: Pointer to the variable to which the total data length of all1068 *   descriptors in the SRP_CMD request will be written.1069 * @imm_data_offset: [in] Offset in SRP_CMD requests at which immediate data1070 *   starts.1071 *1072 * This function initializes ioctx->nrbuf and ioctx->r_bufs.1073 *1074 * Returns -EINVAL when the SRP_CMD request contains inconsistent descriptors;1075 * -ENOMEM when memory allocation fails and zero upon success.1076 */1077static int srpt_get_desc_tbl(struct srpt_recv_ioctx *recv_ioctx,1078		struct srpt_send_ioctx *ioctx,1079		struct srp_cmd *srp_cmd, enum dma_data_direction *dir,1080		struct scatterlist **sg, unsigned int *sg_cnt, u64 *data_len,1081		u16 imm_data_offset)1082{1083	BUG_ON(!dir);1084	BUG_ON(!data_len);1085 1086	/*1087	 * The lower four bits of the buffer format field contain the DATA-IN1088	 * buffer descriptor format, and the highest four bits contain the1089	 * DATA-OUT buffer descriptor format.1090	 */1091	if (srp_cmd->buf_fmt & 0xf)1092		/* DATA-IN: transfer data from target to initiator (read). */1093		*dir = DMA_FROM_DEVICE;1094	else if (srp_cmd->buf_fmt >> 4)1095		/* DATA-OUT: transfer data from initiator to target (write). */1096		*dir = DMA_TO_DEVICE;1097	else1098		*dir = DMA_NONE;1099 1100	/* initialize data_direction early as srpt_alloc_rw_ctxs needs it */1101	ioctx->cmd.data_direction = *dir;1102 1103	if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_DIRECT) ||1104	    ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_DIRECT)) {1105		struct srp_direct_buf *db = srpt_get_desc_buf(srp_cmd);1106 1107		*data_len = be32_to_cpu(db->len);1108		return srpt_alloc_rw_ctxs(ioctx, db, 1, sg, sg_cnt);1109	} else if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_INDIRECT) ||1110		   ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_INDIRECT)) {1111		struct srp_indirect_buf *idb = srpt_get_desc_buf(srp_cmd);1112		int nbufs = be32_to_cpu(idb->table_desc.len) /1113				sizeof(struct srp_direct_buf);1114 1115		if (nbufs >1116		    (srp_cmd->data_out_desc_cnt + srp_cmd->data_in_desc_cnt)) {1117			pr_err("received unsupported SRP_CMD request type (%u out + %u in != %u / %zu)\n",1118			       srp_cmd->data_out_desc_cnt,1119			       srp_cmd->data_in_desc_cnt,1120			       be32_to_cpu(idb->table_desc.len),1121			       sizeof(struct srp_direct_buf));1122			return -EINVAL;1123		}1124 1125		*data_len = be32_to_cpu(idb->len);1126		return srpt_alloc_rw_ctxs(ioctx, idb->desc_list, nbufs,1127				sg, sg_cnt);1128	} else if ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_IMM) {1129		struct srp_imm_buf *imm_buf = srpt_get_desc_buf(srp_cmd);1130		void *data = (void *)srp_cmd + imm_data_offset;1131		uint32_t len = be32_to_cpu(imm_buf->len);1132		uint32_t req_size = imm_data_offset + len;1133 1134		if (req_size > srp_max_req_size) {1135			pr_err("Immediate data (length %d + %d) exceeds request size %d\n",1136			       imm_data_offset, len, srp_max_req_size);1137			return -EINVAL;1138		}1139		if (recv_ioctx->byte_len < req_size) {1140			pr_err("Received too few data - %d < %d\n",1141			       recv_ioctx->byte_len, req_size);1142			return -EIO;1143		}1144		/*1145		 * The immediate data buffer descriptor must occur before the1146		 * immediate data itself.1147		 */1148		if ((void *)(imm_buf + 1) > (void *)data) {1149			pr_err("Received invalid write request\n");1150			return -EINVAL;1151		}1152		*data_len = len;1153		ioctx->recv_ioctx = recv_ioctx;1154		if ((uintptr_t)data & 511) {1155			pr_warn_once("Internal error - the receive buffers are not aligned properly.\n");1156			return -EINVAL;1157		}1158		sg_init_one(&ioctx->imm_sg, data, len);1159		*sg = &ioctx->imm_sg;1160		*sg_cnt = 1;1161		return 0;1162	} else {1163		*data_len = 0;1164		return 0;1165	}1166}1167 1168/**1169 * srpt_init_ch_qp - initialize queue pair attributes1170 * @ch: SRPT RDMA channel.1171 * @qp: Queue pair pointer.1172 *1173 * Initialized the attributes of queue pair 'qp' by allowing local write,1174 * remote read and remote write. Also transitions 'qp' to state IB_QPS_INIT.1175 */1176static int srpt_init_ch_qp(struct srpt_rdma_ch *ch, struct ib_qp *qp)1177{1178	struct ib_qp_attr *attr;1179	int ret;1180 1181	WARN_ON_ONCE(ch->using_rdma_cm);1182 1183	attr = kzalloc(sizeof(*attr), GFP_KERNEL);1184	if (!attr)1185		return -ENOMEM;1186 1187	attr->qp_state = IB_QPS_INIT;1188	attr->qp_access_flags = IB_ACCESS_LOCAL_WRITE;1189	attr->port_num = ch->sport->port;1190 1191	ret = ib_find_cached_pkey(ch->sport->sdev->device, ch->sport->port,1192				  ch->pkey, &attr->pkey_index);1193	if (ret < 0)1194		pr_err("Translating pkey %#x failed (%d) - using index 0\n",1195		       ch->pkey, ret);1196 1197	ret = ib_modify_qp(qp, attr,1198			   IB_QP_STATE | IB_QP_ACCESS_FLAGS | IB_QP_PORT |1199			   IB_QP_PKEY_INDEX);1200 1201	kfree(attr);1202	return ret;1203}1204 1205/**1206 * srpt_ch_qp_rtr - change the state of a channel to 'ready to receive' (RTR)1207 * @ch: channel of the queue pair.1208 * @qp: queue pair to change the state of.1209 *1210 * Returns zero upon success and a negative value upon failure.1211 *1212 * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system.1213 * If this structure ever becomes larger, it might be necessary to allocate1214 * it dynamically instead of on the stack.1215 */1216static int srpt_ch_qp_rtr(struct srpt_rdma_ch *ch, struct ib_qp *qp)1217{1218	struct ib_qp_attr qp_attr;1219	int attr_mask;1220	int ret;1221 1222	WARN_ON_ONCE(ch->using_rdma_cm);1223 1224	qp_attr.qp_state = IB_QPS_RTR;1225	ret = ib_cm_init_qp_attr(ch->ib_cm.cm_id, &qp_attr, &attr_mask);1226	if (ret)1227		goto out;1228 1229	qp_attr.max_dest_rd_atomic = 4;1230 1231	ret = ib_modify_qp(qp, &qp_attr, attr_mask);1232 1233out:1234	return ret;1235}1236 1237/**1238 * srpt_ch_qp_rts - change the state of a channel to 'ready to send' (RTS)1239 * @ch: channel of the queue pair.1240 * @qp: queue pair to change the state of.1241 *1242 * Returns zero upon success and a negative value upon failure.1243 *1244 * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system.1245 * If this structure ever becomes larger, it might be necessary to allocate1246 * it dynamically instead of on the stack.1247 */1248static int srpt_ch_qp_rts(struct srpt_rdma_ch *ch, struct ib_qp *qp)1249{1250	struct ib_qp_attr qp_attr;1251	int attr_mask;1252	int ret;1253 1254	qp_attr.qp_state = IB_QPS_RTS;1255	ret = ib_cm_init_qp_attr(ch->ib_cm.cm_id, &qp_attr, &attr_mask);1256	if (ret)1257		goto out;1258 1259	qp_attr.max_rd_atomic = 4;1260 1261	ret = ib_modify_qp(qp, &qp_attr, attr_mask);1262 1263out:1264	return ret;1265}1266 1267/**1268 * srpt_ch_qp_err - set the channel queue pair state to 'error'1269 * @ch: SRPT RDMA channel.1270 */1271static int srpt_ch_qp_err(struct srpt_rdma_ch *ch)1272{1273	struct ib_qp_attr qp_attr;1274 1275	qp_attr.qp_state = IB_QPS_ERR;1276	return ib_modify_qp(ch->qp, &qp_attr, IB_QP_STATE);1277}1278 1279/**1280 * srpt_get_send_ioctx - obtain an I/O context for sending to the initiator1281 * @ch: SRPT RDMA channel.1282 */1283static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch)1284{1285	struct srpt_send_ioctx *ioctx;1286	int tag, cpu;1287 1288	BUG_ON(!ch);1289 1290	tag = sbitmap_queue_get(&ch->sess->sess_tag_pool, &cpu);1291	if (tag < 0)1292		return NULL;1293 1294	ioctx = ch->ioctx_ring[tag];1295	BUG_ON(ioctx->ch != ch);1296	ioctx->state = SRPT_STATE_NEW;1297	WARN_ON_ONCE(ioctx->recv_ioctx);1298	ioctx->n_rdma = 0;1299	ioctx->n_rw_ctx = 0;1300	ioctx->queue_status_only = false;1301	/*1302	 * transport_init_se_cmd() does not initialize all fields, so do it1303	 * here.1304	 */1305	memset(&ioctx->cmd, 0, sizeof(ioctx->cmd));1306	memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data));1307	ioctx->cmd.map_tag = tag;1308	ioctx->cmd.map_cpu = cpu;1309 1310	return ioctx;1311}1312 1313/**1314 * srpt_abort_cmd - abort a SCSI command1315 * @ioctx:   I/O context associated with the SCSI command.1316 */1317static int srpt_abort_cmd(struct srpt_send_ioctx *ioctx)1318{1319	enum srpt_command_state state;1320 1321	BUG_ON(!ioctx);1322 1323	/*1324	 * If the command is in a state where the target core is waiting for1325	 * the ib_srpt driver, change the state to the next state.1326	 */1327 1328	state = ioctx->state;1329	switch (state) {1330	case SRPT_STATE_NEED_DATA:1331		ioctx->state = SRPT_STATE_DATA_IN;1332		break;1333	case SRPT_STATE_CMD_RSP_SENT:1334	case SRPT_STATE_MGMT_RSP_SENT:1335		ioctx->state = SRPT_STATE_DONE;1336		break;1337	default:1338		WARN_ONCE(true, "%s: unexpected I/O context state %d\n",1339			  __func__, state);1340		break;1341	}1342 1343	pr_debug("Aborting cmd with state %d -> %d and tag %lld\n", state,1344		 ioctx->state, ioctx->cmd.tag);1345 1346	switch (state) {1347	case SRPT_STATE_NEW:1348	case SRPT_STATE_DATA_IN:1349	case SRPT_STATE_MGMT:1350	case SRPT_STATE_DONE:1351		/*1352		 * Do nothing - defer abort processing until1353		 * srpt_queue_response() is invoked.1354		 */1355		break;1356	case SRPT_STATE_NEED_DATA:1357		pr_debug("tag %#llx: RDMA read error\n", ioctx->cmd.tag);1358		transport_generic_request_failure(&ioctx->cmd,1359					TCM_CHECK_CONDITION_ABORT_CMD);1360		break;1361	case SRPT_STATE_CMD_RSP_SENT:1362		/*1363		 * SRP_RSP sending failed or the SRP_RSP send completion has1364		 * not been received in time.1365		 */1366		transport_generic_free_cmd(&ioctx->cmd, 0);1367		break;1368	case SRPT_STATE_MGMT_RSP_SENT:1369		transport_generic_free_cmd(&ioctx->cmd, 0);1370		break;1371	default:1372		WARN(1, "Unexpected command state (%d)", state);1373		break;1374	}1375 1376	return state;1377}1378 1379/**1380 * srpt_rdma_read_done - RDMA read completion callback1381 * @cq: Completion queue.1382 * @wc: Work completion.1383 *1384 * XXX: what is now target_execute_cmd used to be asynchronous, and unmapping1385 * the data that has been transferred via IB RDMA had to be postponed until the1386 * check_stop_free() callback.  None of this is necessary anymore and needs to1387 * be cleaned up.1388 */1389static void srpt_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc)1390{1391	struct srpt_rdma_ch *ch = wc->qp->qp_context;1392	struct srpt_send_ioctx *ioctx =1393		container_of(wc->wr_cqe, struct srpt_send_ioctx, rdma_cqe);1394 1395	WARN_ON(ioctx->n_rdma <= 0);1396	atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);1397	ioctx->n_rdma = 0;1398 1399	if (unlikely(wc->status != IB_WC_SUCCESS)) {1400		pr_info("RDMA_READ for ioctx 0x%p failed with status %d\n",1401			ioctx, wc->status);1402		srpt_abort_cmd(ioctx);1403		return;1404	}1405 1406	if (srpt_test_and_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA,1407					SRPT_STATE_DATA_IN))1408		target_execute_cmd(&ioctx->cmd);1409	else1410		pr_err("%s[%d]: wrong state = %d\n", __func__,1411		       __LINE__, ioctx->state);1412}1413 1414/**1415 * srpt_build_cmd_rsp - build a SRP_RSP response1416 * @ch: RDMA channel through which the request has been received.1417 * @ioctx: I/O context associated with the SRP_CMD request. The response will1418 *   be built in the buffer ioctx->buf points at and hence this function will1419 *   overwrite the request data.1420 * @tag: tag of the request for which this response is being generated.1421 * @status: value for the STATUS field of the SRP_RSP information unit.1422 *1423 * Returns the size in bytes of the SRP_RSP response.1424 *1425 * An SRP_RSP response contains a SCSI status or service response. See also1426 * section 6.9 in the SRP r16a document for the format of an SRP_RSP1427 * response. See also SPC-2 for more information about sense data.1428 */1429static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch,1430			      struct srpt_send_ioctx *ioctx, u64 tag,1431			      int status)1432{1433	struct se_cmd *cmd = &ioctx->cmd;1434	struct srp_rsp *srp_rsp;1435	const u8 *sense_data;1436	int sense_data_len, max_sense_len;1437	u32 resid = cmd->residual_count;1438 1439	/*1440	 * The lowest bit of all SAM-3 status codes is zero (see also1441	 * paragraph 5.3 in SAM-3).1442	 */1443	WARN_ON(status & 1);1444 1445	srp_rsp = ioctx->ioctx.buf;1446	BUG_ON(!srp_rsp);1447 1448	sense_data = ioctx->sense_data;1449	sense_data_len = ioctx->cmd.scsi_sense_length;1450	WARN_ON(sense_data_len > sizeof(ioctx->sense_data));1451 1452	memset(srp_rsp, 0, sizeof(*srp_rsp));1453	srp_rsp->opcode = SRP_RSP;1454	srp_rsp->req_lim_delta =1455		cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0));1456	srp_rsp->tag = tag;1457	srp_rsp->status = status;1458 1459	if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {1460		if (cmd->data_direction == DMA_TO_DEVICE) {1461			/* residual data from an underflow write */1462			srp_rsp->flags = SRP_RSP_FLAG_DOUNDER;1463			srp_rsp->data_out_res_cnt = cpu_to_be32(resid);1464		} else if (cmd->data_direction == DMA_FROM_DEVICE) {1465			/* residual data from an underflow read */1466			srp_rsp->flags = SRP_RSP_FLAG_DIUNDER;1467			srp_rsp->data_in_res_cnt = cpu_to_be32(resid);1468		}1469	} else if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {1470		if (cmd->data_direction == DMA_TO_DEVICE) {1471			/* residual data from an overflow write */1472			srp_rsp->flags = SRP_RSP_FLAG_DOOVER;1473			srp_rsp->data_out_res_cnt = cpu_to_be32(resid);1474		} else if (cmd->data_direction == DMA_FROM_DEVICE) {1475			/* residual data from an overflow read */1476			srp_rsp->flags = SRP_RSP_FLAG_DIOVER;1477			srp_rsp->data_in_res_cnt = cpu_to_be32(resid);1478		}1479	}1480 1481	if (sense_data_len) {1482		BUILD_BUG_ON(MIN_MAX_RSP_SIZE <= sizeof(*srp_rsp));1483		max_sense_len = ch->max_ti_iu_len - sizeof(*srp_rsp);1484		if (sense_data_len > max_sense_len) {1485			pr_warn("truncated sense data from %d to %d bytes\n",1486				sense_data_len, max_sense_len);1487			sense_data_len = max_sense_len;1488		}1489 1490		srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID;1491		srp_rsp->sense_data_len = cpu_to_be32(sense_data_len);1492		memcpy(srp_rsp->data, sense_data, sense_data_len);1493	}1494 1495	return sizeof(*srp_rsp) + sense_data_len;1496}1497 1498/**1499 * srpt_build_tskmgmt_rsp - build a task management response1500 * @ch:       RDMA channel through which the request has been received.1501 * @ioctx:    I/O context in which the SRP_RSP response will be built.1502 * @rsp_code: RSP_CODE that will be stored in the response.1503 * @tag:      Tag of the request for which this response is being generated.1504 *1505 * Returns the size in bytes of the SRP_RSP response.1506 *1507 * An SRP_RSP response contains a SCSI status or service response. See also1508 * section 6.9 in the SRP r16a document for the format of an SRP_RSP1509 * response.1510 */1511static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch,1512				  struct srpt_send_ioctx *ioctx,1513				  u8 rsp_code, u64 tag)1514{1515	struct srp_rsp *srp_rsp;1516	int resp_data_len;1517	int resp_len;1518 1519	resp_data_len = 4;1520	resp_len = sizeof(*srp_rsp) + resp_data_len;1521 1522	srp_rsp = ioctx->ioctx.buf;1523	BUG_ON(!srp_rsp);1524	memset(srp_rsp, 0, sizeof(*srp_rsp));1525 1526	srp_rsp->opcode = SRP_RSP;1527	srp_rsp->req_lim_delta =1528		cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0));1529	srp_rsp->tag = tag;1530 1531	srp_rsp->flags |= SRP_RSP_FLAG_RSPVALID;1532	srp_rsp->resp_data_len = cpu_to_be32(resp_data_len);1533	srp_rsp->data[3] = rsp_code;1534 1535	return resp_len;1536}1537 1538static int srpt_check_stop_free(struct se_cmd *cmd)1539{1540	struct srpt_send_ioctx *ioctx = container_of(cmd,1541				struct srpt_send_ioctx, cmd);1542 1543	return target_put_sess_cmd(&ioctx->cmd);1544}1545 1546/**1547 * srpt_handle_cmd - process a SRP_CMD information unit1548 * @ch: SRPT RDMA channel.1549 * @recv_ioctx: Receive I/O context.1550 * @send_ioctx: Send I/O context.1551 */1552static void srpt_handle_cmd(struct srpt_rdma_ch *ch,1553			    struct srpt_recv_ioctx *recv_ioctx,1554			    struct srpt_send_ioctx *send_ioctx)1555{1556	struct se_cmd *cmd;1557	struct srp_cmd *srp_cmd;1558	struct scatterlist *sg = NULL;1559	unsigned sg_cnt = 0;1560	u64 data_len;1561	enum dma_data_direction dir;1562	int rc;1563 1564	BUG_ON(!send_ioctx);1565 1566	srp_cmd = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset;1567	cmd = &send_ioctx->cmd;1568	cmd->tag = srp_cmd->tag;1569 1570	switch (srp_cmd->task_attr) {1571	case SRP_CMD_SIMPLE_Q:1572		cmd->sam_task_attr = TCM_SIMPLE_TAG;1573		break;1574	case SRP_CMD_ORDERED_Q:1575	default:1576		cmd->sam_task_attr = TCM_ORDERED_TAG;1577		break;1578	case SRP_CMD_HEAD_OF_Q:1579		cmd->sam_task_attr = TCM_HEAD_TAG;1580		break;1581	case SRP_CMD_ACA:1582		cmd->sam_task_attr = TCM_ACA_TAG;1583		break;1584	}1585 1586	rc = srpt_get_desc_tbl(recv_ioctx, send_ioctx, srp_cmd, &dir,1587			       &sg, &sg_cnt, &data_len, ch->imm_data_offset);1588	if (rc) {1589		if (rc != -EAGAIN) {1590			pr_err("0x%llx: parsing SRP descriptor table failed.\n",1591			       srp_cmd->tag);1592		}1593		goto busy;1594	}1595 1596	rc = target_init_cmd(cmd, ch->sess, &send_ioctx->sense_data[0],1597			     scsilun_to_int(&srp_cmd->lun), data_len,1598			     TCM_SIMPLE_TAG, dir, TARGET_SCF_ACK_KREF);1599	if (rc != 0) {1600		pr_debug("target_submit_cmd() returned %d for tag %#llx\n", rc,1601			 srp_cmd->tag);1602		goto busy;1603	}1604 1605	if (target_submit_prep(cmd, srp_cmd->cdb, sg, sg_cnt, NULL, 0, NULL, 0,1606			       GFP_KERNEL))1607		return;1608 1609	target_submit(cmd);1610	return;1611 1612busy:1613	target_send_busy(cmd);1614}1615 1616static int srp_tmr_to_tcm(int fn)1617{1618	switch (fn) {1619	case SRP_TSK_ABORT_TASK:1620		return TMR_ABORT_TASK;1621	case SRP_TSK_ABORT_TASK_SET:1622		return TMR_ABORT_TASK_SET;1623	case SRP_TSK_CLEAR_TASK_SET:1624		return TMR_CLEAR_TASK_SET;1625	case SRP_TSK_LUN_RESET:1626		return TMR_LUN_RESET;1627	case SRP_TSK_CLEAR_ACA:1628		return TMR_CLEAR_ACA;1629	default:1630		return -1;1631	}1632}1633 1634/**1635 * srpt_handle_tsk_mgmt - process a SRP_TSK_MGMT information unit1636 * @ch: SRPT RDMA channel.1637 * @recv_ioctx: Receive I/O context.1638 * @send_ioctx: Send I/O context.1639 *1640 * Returns 0 if and only if the request will be processed by the target core.1641 *1642 * For more information about SRP_TSK_MGMT information units, see also section1643 * 6.7 in the SRP r16a document.1644 */1645static void srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch,1646				 struct srpt_recv_ioctx *recv_ioctx,1647				 struct srpt_send_ioctx *send_ioctx)1648{1649	struct srp_tsk_mgmt *srp_tsk;1650	struct se_cmd *cmd;1651	struct se_session *sess = ch->sess;1652	int tcm_tmr;1653	int rc;1654 1655	BUG_ON(!send_ioctx);1656 1657	srp_tsk = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset;1658	cmd = &send_ioctx->cmd;1659 1660	pr_debug("recv tsk_mgmt fn %d for task_tag %lld and cmd tag %lld ch %p sess %p\n",1661		 srp_tsk->tsk_mgmt_func, srp_tsk->task_tag, srp_tsk->tag, ch,1662		 ch->sess);1663 1664	srpt_set_cmd_state(send_ioctx, SRPT_STATE_MGMT);1665	send_ioctx->cmd.tag = srp_tsk->tag;1666	tcm_tmr = srp_tmr_to_tcm(srp_tsk->tsk_mgmt_func);1667	rc = target_submit_tmr(&send_ioctx->cmd, sess, NULL,1668			       scsilun_to_int(&srp_tsk->lun), srp_tsk, tcm_tmr,1669			       GFP_KERNEL, srp_tsk->task_tag,1670			       TARGET_SCF_ACK_KREF);1671	if (rc != 0) {1672		send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED;1673		cmd->se_tfo->queue_tm_rsp(cmd);1674	}1675	return;1676}1677 1678/**1679 * srpt_handle_new_iu - process a newly received information unit1680 * @ch:    RDMA channel through which the information unit has been received.1681 * @recv_ioctx: Receive I/O context associated with the information unit.1682 */1683static bool1684srpt_handle_new_iu(struct srpt_rdma_ch *ch, struct srpt_recv_ioctx *recv_ioctx)1685{1686	struct srpt_send_ioctx *send_ioctx = NULL;1687	struct srp_cmd *srp_cmd;1688	bool res = false;1689	u8 opcode;1690 1691	BUG_ON(!ch);1692	BUG_ON(!recv_ioctx);1693 1694	if (unlikely(ch->state == CH_CONNECTING))1695		goto push;1696 1697	ib_dma_sync_single_for_cpu(ch->sport->sdev->device,1698				   recv_ioctx->ioctx.dma,1699				   recv_ioctx->ioctx.offset + srp_max_req_size,1700				   DMA_FROM_DEVICE);1701 1702	srp_cmd = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset;1703	opcode = srp_cmd->opcode;1704	if (opcode == SRP_CMD || opcode == SRP_TSK_MGMT) {1705		send_ioctx = srpt_get_send_ioctx(ch);1706		if (unlikely(!send_ioctx))1707			goto push;1708	}1709 1710	if (!list_empty(&recv_ioctx->wait_list)) {1711		WARN_ON_ONCE(!ch->processing_wait_list);1712		list_del_init(&recv_ioctx->wait_list);1713	}1714 1715	switch (opcode) {1716	case SRP_CMD:1717		srpt_handle_cmd(ch, recv_ioctx, send_ioctx);1718		break;1719	case SRP_TSK_MGMT:1720		srpt_handle_tsk_mgmt(ch, recv_ioctx, send_ioctx);1721		break;1722	case SRP_I_LOGOUT:1723		pr_err("Not yet implemented: SRP_I_LOGOUT\n");1724		break;1725	case SRP_CRED_RSP:1726		pr_debug("received SRP_CRED_RSP\n");1727		break;1728	case SRP_AER_RSP:1729		pr_debug("received SRP_AER_RSP\n");1730		break;1731	case SRP_RSP:1732		pr_err("Received SRP_RSP\n");1733		break;1734	default:1735		pr_err("received IU with unknown opcode 0x%x\n", opcode);1736		break;1737	}1738 1739	if (!send_ioctx || !send_ioctx->recv_ioctx)1740		srpt_post_recv(ch->sport->sdev, ch, recv_ioctx);1741	res = true;1742 1743out:1744	return res;1745 1746push:1747	if (list_empty(&recv_ioctx->wait_list)) {1748		WARN_ON_ONCE(ch->processing_wait_list);1749		list_add_tail(&recv_ioctx->wait_list, &ch->cmd_wait_list);1750	}1751	goto out;1752}1753 1754static void srpt_recv_done(struct ib_cq *cq, struct ib_wc *wc)1755{1756	struct srpt_rdma_ch *ch = wc->qp->qp_context;1757	struct srpt_recv_ioctx *ioctx =1758		container_of(wc->wr_cqe, struct srpt_recv_ioctx, ioctx.cqe);1759 1760	if (wc->status == IB_WC_SUCCESS) {1761		int req_lim;1762 1763		req_lim = atomic_dec_return(&ch->req_lim);1764		if (unlikely(req_lim < 0))1765			pr_err("req_lim = %d < 0\n", req_lim);1766		ioctx->byte_len = wc->byte_len;1767		srpt_handle_new_iu(ch, ioctx);1768	} else {1769		pr_info_ratelimited("receiving failed for ioctx %p with status %d\n",1770				    ioctx, wc->status);1771	}1772}1773 1774/*1775 * This function must be called from the context in which RDMA completions are1776 * processed because it accesses the wait list without protection against1777 * access from other threads.1778 */1779static void srpt_process_wait_list(struct srpt_rdma_ch *ch)1780{1781	struct srpt_recv_ioctx *recv_ioctx, *tmp;1782 1783	WARN_ON_ONCE(ch->state == CH_CONNECTING);1784 1785	if (list_empty(&ch->cmd_wait_list))1786		return;1787 1788	WARN_ON_ONCE(ch->processing_wait_list);1789	ch->processing_wait_list = true;1790	list_for_each_entry_safe(recv_ioctx, tmp, &ch->cmd_wait_list,1791				 wait_list) {1792		if (!srpt_handle_new_iu(ch, recv_ioctx))1793			break;1794	}1795	ch->processing_wait_list = false;1796}1797 1798/**1799 * srpt_send_done - send completion callback1800 * @cq: Completion queue.1801 * @wc: Work completion.1802 *1803 * Note: Although this has not yet been observed during tests, at least in1804 * theory it is possible that the srpt_get_send_ioctx() call invoked by1805 * srpt_handle_new_iu() fails. This is possible because the req_lim_delta1806 * value in each response is set to one, and it is possible that this response1807 * makes the initiator send a new request before the send completion for that1808 * response has been processed. This could e.g. happen if the call to1809 * srpt_put_send_iotcx() is delayed because of a higher priority interrupt or1810 * if IB retransmission causes generation of the send completion to be1811 * delayed. Incoming information units for which srpt_get_send_ioctx() fails1812 * are queued on cmd_wait_list. The code below processes these delayed1813 * requests one at a time.1814 */1815static void srpt_send_done(struct ib_cq *cq, struct ib_wc *wc)1816{1817	struct srpt_rdma_ch *ch = wc->qp->qp_context;1818	struct srpt_send_ioctx *ioctx =1819		container_of(wc->wr_cqe, struct srpt_send_ioctx, ioctx.cqe);1820	enum srpt_command_state state;1821 1822	state = srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);1823 1824	WARN_ON(state != SRPT_STATE_CMD_RSP_SENT &&1825		state != SRPT_STATE_MGMT_RSP_SENT);1826 1827	atomic_add(1 + ioctx->n_rdma, &ch->sq_wr_avail);1828 1829	if (wc->status != IB_WC_SUCCESS)1830		pr_info("sending response for ioctx 0x%p failed with status %d\n",1831			ioctx, wc->status);1832 1833	if (state != SRPT_STATE_DONE) {1834		transport_generic_free_cmd(&ioctx->cmd, 0);1835	} else {1836		pr_err("IB completion has been received too late for wr_id = %u.\n",1837		       ioctx->ioctx.index);1838	}1839 1840	srpt_process_wait_list(ch);1841}1842 1843/**1844 * srpt_create_ch_ib - create receive and send completion queues1845 * @ch: SRPT RDMA channel.1846 */1847static int srpt_create_ch_ib(struct srpt_rdma_ch *ch)1848{1849	struct ib_qp_init_attr *qp_init;1850	struct srpt_port *sport = ch->sport;1851	struct srpt_device *sdev = sport->sdev;1852	const struct ib_device_attr *attrs = &sdev->device->attrs;1853	int sq_size = sport->port_attrib.srp_sq_size;1854	int i, ret;1855 1856	WARN_ON(ch->rq_size < 1);1857 1858	ret = -ENOMEM;1859	qp_init = kzalloc(sizeof(*qp_init), GFP_KERNEL);1860	if (!qp_init)1861		goto out;1862 1863retry:1864	ch->cq = ib_cq_pool_get(sdev->device, ch->rq_size + sq_size, -1,1865				 IB_POLL_WORKQUEUE);1866	if (IS_ERR(ch->cq)) {1867		ret = PTR_ERR(ch->cq);1868		pr_err("failed to create CQ cqe= %d ret= %d\n",1869		       ch->rq_size + sq_size, ret);1870		goto out;1871	}1872	ch->cq_size = ch->rq_size + sq_size;1873 1874	qp_init->qp_context = (void *)ch;1875	qp_init->event_handler = srpt_qp_event;1876	qp_init->send_cq = ch->cq;1877	qp_init->recv_cq = ch->cq;1878	qp_init->sq_sig_type = IB_SIGNAL_REQ_WR;1879	qp_init->qp_type = IB_QPT_RC;1880	/*1881	 * We divide up our send queue size into half SEND WRs to send the1882	 * completions, and half R/W contexts to actually do the RDMA1883	 * READ/WRITE transfers.  Note that we need to allocate CQ slots for1884	 * both both, as RDMA contexts will also post completions for the1885	 * RDMA READ case.1886	 */1887	qp_init->cap.max_send_wr = min(sq_size / 2, attrs->max_qp_wr);1888	qp_init->cap.max_rdma_ctxs = sq_size / 2;1889	qp_init->cap.max_send_sge = attrs->max_send_sge;1890	qp_init->cap.max_recv_sge = 1;1891	qp_init->port_num = ch->sport->port;1892	if (sdev->use_srq)1893		qp_init->srq = sdev->srq;1894	else1895		qp_init->cap.max_recv_wr = ch->rq_size;1896 1897	if (ch->using_rdma_cm) {1898		ret = rdma_create_qp(ch->rdma_cm.cm_id, sdev->pd, qp_init);1899		ch->qp = ch->rdma_cm.cm_id->qp;1900	} else {1901		ch->qp = ib_create_qp(sdev->pd, qp_init);1902		if (!IS_ERR(ch->qp)) {1903			ret = srpt_init_ch_qp(ch, ch->qp);1904			if (ret)1905				ib_destroy_qp(ch->qp);1906		} else {1907			ret = PTR_ERR(ch->qp);1908		}1909	}1910	if (ret) {1911		bool retry = sq_size > MIN_SRPT_SQ_SIZE;1912 1913		if (retry) {1914			pr_debug("failed to create queue pair with sq_size = %d (%d) - retrying\n",1915				 sq_size, ret);1916			ib_cq_pool_put(ch->cq, ch->cq_size);1917			sq_size = max(sq_size / 2, MIN_SRPT_SQ_SIZE);1918			goto retry;1919		} else {1920			pr_err("failed to create queue pair with sq_size = %d (%d)\n",1921			       sq_size, ret);1922			goto err_destroy_cq;1923		}1924	}1925 1926	atomic_set(&ch->sq_wr_avail, qp_init->cap.max_send_wr);1927 1928	pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d ch= %p\n",1929		 __func__, ch->cq->cqe, qp_init->cap.max_send_sge,1930		 qp_init->cap.max_send_wr, ch);1931 1932	if (!sdev->use_srq)1933		for (i = 0; i < ch->rq_size; i++)1934			srpt_post_recv(sdev, ch, ch->ioctx_recv_ring[i]);1935 1936out:1937	kfree(qp_init);1938	return ret;1939 1940err_destroy_cq:1941	ch->qp = NULL;1942	ib_cq_pool_put(ch->cq, ch->cq_size);1943	goto out;1944}1945 1946static void srpt_destroy_ch_ib(struct srpt_rdma_ch *ch)1947{1948	ib_destroy_qp(ch->qp);1949	ib_cq_pool_put(ch->cq, ch->cq_size);1950}1951 1952/**1953 * srpt_close_ch - close a RDMA channel1954 * @ch: SRPT RDMA channel.1955 *1956 * Make sure all resources associated with the channel will be deallocated at1957 * an appropriate time.1958 *1959 * Returns true if and only if the channel state has been modified into1960 * CH_DRAINING.1961 */1962static bool srpt_close_ch(struct srpt_rdma_ch *ch)1963{1964	int ret;1965 1966	if (!srpt_set_ch_state(ch, CH_DRAINING)) {1967		pr_debug("%s: already closed\n", ch->sess_name);1968		return false;1969	}1970 1971	kref_get(&ch->kref);1972 1973	ret = srpt_ch_qp_err(ch);1974	if (ret < 0)1975		pr_err("%s-%d: changing queue pair into error state failed: %d\n",1976		       ch->sess_name, ch->qp->qp_num, ret);1977 1978	ret = srpt_zerolength_write(ch);1979	if (ret < 0) {1980		pr_err("%s-%d: queuing zero-length write failed: %d\n",1981		       ch->sess_name, ch->qp->qp_num, ret);1982		if (srpt_set_ch_state(ch, CH_DISCONNECTED))1983			schedule_work(&ch->release_work);1984		else1985			WARN_ON_ONCE(true);1986	}1987 1988	kref_put(&ch->kref, srpt_free_ch);1989 1990	return true;1991}1992 1993/*1994 * Change the channel state into CH_DISCONNECTING. If a channel has not yet1995 * reached the connected state, close it. If a channel is in the connected1996 * state, send a DREQ. If a DREQ has been received, send a DREP. Note: it is1997 * the responsibility of the caller to ensure that this function is not1998 * invoked concurrently with the code that accepts a connection. This means1999 * that this function must either be invoked from inside a CM callback2000 * function or that it must be invoked with the srpt_port.mutex held.2001 */2002static int srpt_disconnect_ch(struct srpt_rdma_ch *ch)2003{2004	int ret;2005 2006	if (!srpt_set_ch_state(ch, CH_DISCONNECTING))2007		return -ENOTCONN;2008 2009	if (ch->using_rdma_cm) {2010		ret = rdma_disconnect(ch->rdma_cm.cm_id);2011	} else {2012		ret = ib_send_cm_dreq(ch->ib_cm.cm_id, NULL, 0);2013		if (ret < 0)2014			ret = ib_send_cm_drep(ch->ib_cm.cm_id, NULL, 0);2015	}2016 2017	if (ret < 0 && srpt_close_ch(ch))2018		ret = 0;2019 2020	return ret;2021}2022 2023/* Send DREQ and wait for DREP. */2024static void srpt_disconnect_ch_sync(struct srpt_rdma_ch *ch)2025{2026	DECLARE_COMPLETION_ONSTACK(closed);2027	struct srpt_port *sport = ch->sport;2028 2029	pr_debug("ch %s-%d state %d\n", ch->sess_name, ch->qp->qp_num,2030		 ch->state);2031 2032	ch->closed = &closed;2033 2034	mutex_lock(&sport->mutex);2035	srpt_disconnect_ch(ch);2036	mutex_unlock(&sport->mutex);2037 2038	while (wait_for_completion_timeout(&closed, 5 * HZ) == 0)2039		pr_info("%s(%s-%d state %d): still waiting ...\n", __func__,2040			ch->sess_name, ch->qp->qp_num, ch->state);2041 2042}2043 2044static void __srpt_close_all_ch(struct srpt_port *sport)2045{2046	struct srpt_nexus *nexus;2047	struct srpt_rdma_ch *ch;2048 2049	lockdep_assert_held(&sport->mutex);2050 2051	list_for_each_entry(nexus, &sport->nexus_list, entry) {2052		list_for_each_entry(ch, &nexus->ch_list, list) {2053			if (srpt_disconnect_ch(ch) >= 0)2054				pr_info("Closing channel %s-%d because target %s_%d has been disabled\n",2055					ch->sess_name, ch->qp->qp_num,2056					dev_name(&sport->sdev->device->dev),2057					sport->port);2058			srpt_close_ch(ch);2059		}2060	}2061}2062 2063/*2064 * Look up (i_port_id, t_port_id) in sport->nexus_list. Create an entry if2065 * it does not yet exist.2066 */2067static struct srpt_nexus *srpt_get_nexus(struct srpt_port *sport,2068					 const u8 i_port_id[16],2069					 const u8 t_port_id[16])2070{2071	struct srpt_nexus *nexus = NULL, *tmp_nexus = NULL, *n;2072 2073	for (;;) {2074		mutex_lock(&sport->mutex);2075		list_for_each_entry(n, &sport->nexus_list, entry) {2076			if (memcmp(n->i_port_id, i_port_id, 16) == 0 &&2077			    memcmp(n->t_port_id, t_port_id, 16) == 0) {2078				nexus = n;2079				break;2080			}2081		}2082		if (!nexus && tmp_nexus) {2083			list_add_tail_rcu(&tmp_nexus->entry,2084					  &sport->nexus_list);2085			swap(nexus, tmp_nexus);2086		}2087		mutex_unlock(&sport->mutex);2088 2089		if (nexus)2090			break;2091		tmp_nexus = kzalloc(sizeof(*nexus), GFP_KERNEL);2092		if (!tmp_nexus) {2093			nexus = ERR_PTR(-ENOMEM);2094			break;2095		}2096		INIT_LIST_HEAD(&tmp_nexus->ch_list);2097		memcpy(tmp_nexus->i_port_id, i_port_id, 16);2098		memcpy(tmp_nexus->t_port_id, t_port_id, 16);2099	}2100 2101	kfree(tmp_nexus);2102 2103	return nexus;2104}2105 2106static void srpt_set_enabled(struct srpt_port *sport, bool enabled)2107	__must_hold(&sport->mutex)2108{2109	lockdep_assert_held(&sport->mutex);2110 2111	if (sport->enabled == enabled)2112		return;2113	sport->enabled = enabled;2114	if (!enabled)2115		__srpt_close_all_ch(sport);2116}2117 2118static void srpt_drop_sport_ref(struct srpt_port *sport)2119{2120	if (atomic_dec_return(&sport->refcount) == 0 && sport->freed_channels)2121		complete(sport->freed_channels);2122}2123 2124static void srpt_free_ch(struct kref *kref)2125{2126	struct srpt_rdma_ch *ch = container_of(kref, struct srpt_rdma_ch, kref);2127 2128	srpt_drop_sport_ref(ch->sport);2129	kfree_rcu(ch, rcu);2130}2131 2132/*2133 * Shut down the SCSI target session, tell the connection manager to2134 * disconnect the associated RDMA channel, transition the QP to the error2135 * state and remove the channel from the channel list. This function is2136 * typically called from inside srpt_zerolength_write_done(). Concurrent2137 * srpt_zerolength_write() calls from inside srpt_close_ch() are possible2138 * as long as the channel is on sport->nexus_list.2139 */2140static void srpt_release_channel_work(struct work_struct *w)2141{2142	struct srpt_rdma_ch *ch;2143	struct srpt_device *sdev;2144	struct srpt_port *sport;2145	struct se_session *se_sess;2146 2147	ch = container_of(w, struct srpt_rdma_ch, release_work);2148	pr_debug("%s-%d\n", ch->sess_name, ch->qp->qp_num);2149 2150	sdev = ch->sport->sdev;2151	BUG_ON(!sdev);2152 2153	se_sess = ch->sess;2154	BUG_ON(!se_sess);2155 2156	target_stop_session(se_sess);2157	target_wait_for_sess_cmds(se_sess);2158 2159	target_remove_session(se_sess);2160	ch->sess = NULL;2161 2162	if (ch->using_rdma_cm)2163		rdma_destroy_id(ch->rdma_cm.cm_id);2164	else2165		ib_destroy_cm_id(ch->ib_cm.cm_id);2166 2167	sport = ch->sport;2168	mutex_lock(&sport->mutex);2169	list_del_rcu(&ch->list);2170	mutex_unlock(&sport->mutex);2171 2172	if (ch->closed)2173		complete(ch->closed);2174 2175	srpt_destroy_ch_ib(ch);2176 2177	srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,2178			     ch->sport->sdev, ch->rq_size,2179			     ch->rsp_buf_cache, DMA_TO_DEVICE);2180 2181	srpt_cache_put(ch->rsp_buf_cache);2182 2183	srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_recv_ring,2184			     sdev, ch->rq_size,2185			     ch->req_buf_cache, DMA_FROM_DEVICE);2186 2187	srpt_cache_put(ch->req_buf_cache);2188 2189	kref_put(&ch->kref, srpt_free_ch);2190}2191 2192/**2193 * srpt_cm_req_recv - process the event IB_CM_REQ_RECEIVED2194 * @sdev: HCA through which the login request was received.2195 * @ib_cm_id: IB/CM connection identifier in case of IB/CM.2196 * @rdma_cm_id: RDMA/CM connection identifier in case of RDMA/CM.2197 * @port_num: Port through which the REQ message was received.2198 * @pkey: P_Key of the incoming connection.2199 * @req: SRP login request.2200 * @src_addr: GID (IB/CM) or IP address (RDMA/CM) of the port that submitted2201 * the login request.2202 *2203 * Ownership of the cm_id is transferred to the target session if this2204 * function returns zero. Otherwise the caller remains the owner of cm_id.2205 */2206static int srpt_cm_req_recv(struct srpt_device *const sdev,2207			    struct ib_cm_id *ib_cm_id,2208			    struct rdma_cm_id *rdma_cm_id,2209			    u8 port_num, __be16 pkey,2210			    const struct srp_login_req *req,2211			    const char *src_addr)2212{2213	struct srpt_port *sport = &sdev->port[port_num - 1];2214	struct srpt_nexus *nexus;2215	struct srp_login_rsp *rsp = NULL;2216	struct srp_login_rej *rej = NULL;2217	union {2218		struct rdma_conn_param rdma_cm;2219		struct ib_cm_rep_param ib_cm;2220	} *rep_param = NULL;2221	struct srpt_rdma_ch *ch = NULL;2222	char i_port_id[36];2223	u32 it_iu_len;2224	int i, tag_num, tag_size, ret;2225	struct srpt_tpg *stpg;2226 2227	WARN_ON_ONCE(irqs_disabled());2228 2229	it_iu_len = be32_to_cpu(req->req_it_iu_len);2230 2231	pr_info("Received SRP_LOGIN_REQ with i_port_id %pI6, t_port_id %pI6 and it_iu_len %d on port %d (guid=%pI6); pkey %#04x\n",2232		req->initiator_port_id, req->target_port_id, it_iu_len,2233		port_num, &sport->gid, be16_to_cpu(pkey));2234 2235	nexus = srpt_get_nexus(sport, req->initiator_port_id,2236			       req->target_port_id);2237	if (IS_ERR(nexus)) {2238		ret = PTR_ERR(nexus);2239		goto out;2240	}2241 2242	ret = -ENOMEM;2243	rsp = kzalloc(sizeof(*rsp), GFP_KERNEL);2244	rej = kzalloc(sizeof(*rej), GFP_KERNEL);2245	rep_param = kzalloc(sizeof(*rep_param), GFP_KERNEL);2246	if (!rsp || !rej || !rep_param)2247		goto out;2248 2249	ret = -EINVAL;2250	if (it_iu_len > srp_max_req_size || it_iu_len < 64) {2251		rej->reason = cpu_to_be32(2252				SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE);2253		pr_err("rejected SRP_LOGIN_REQ because its length (%d bytes) is out of range (%d .. %d)\n",2254		       it_iu_len, 64, srp_max_req_size);2255		goto reject;2256	}2257 2258	if (!sport->enabled) {2259		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2260		pr_info("rejected SRP_LOGIN_REQ because target port %s_%d has not yet been enabled\n",2261			dev_name(&sport->sdev->device->dev), port_num);2262		goto reject;2263	}2264 2265	if (*(__be64 *)req->target_port_id != cpu_to_be64(srpt_service_guid)2266	    || *(__be64 *)(req->target_port_id + 8) !=2267	       cpu_to_be64(srpt_service_guid)) {2268		rej->reason = cpu_to_be32(2269				SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL);2270		pr_err("rejected SRP_LOGIN_REQ because it has an invalid target port identifier.\n");2271		goto reject;2272	}2273 2274	ret = -ENOMEM;2275	ch = kzalloc(sizeof(*ch), GFP_KERNEL);2276	if (!ch) {2277		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2278		pr_err("rejected SRP_LOGIN_REQ because out of memory.\n");2279		goto reject;2280	}2281 2282	kref_init(&ch->kref);2283	ch->pkey = be16_to_cpu(pkey);2284	ch->nexus = nexus;2285	ch->zw_cqe.done = srpt_zerolength_write_done;2286	INIT_WORK(&ch->release_work, srpt_release_channel_work);2287	ch->sport = sport;2288	if (rdma_cm_id) {2289		ch->using_rdma_cm = true;2290		ch->rdma_cm.cm_id = rdma_cm_id;2291		rdma_cm_id->context = ch;2292	} else {2293		ch->ib_cm.cm_id = ib_cm_id;2294		ib_cm_id->context = ch;2295	}2296	/*2297	 * ch->rq_size should be at least as large as the initiator queue2298	 * depth to avoid that the initiator driver has to report QUEUE_FULL2299	 * to the SCSI mid-layer.2300	 */2301	ch->rq_size = min(MAX_SRPT_RQ_SIZE, sdev->device->attrs.max_qp_wr);2302	spin_lock_init(&ch->spinlock);2303	ch->state = CH_CONNECTING;2304	INIT_LIST_HEAD(&ch->cmd_wait_list);2305	ch->max_rsp_size = ch->sport->port_attrib.srp_max_rsp_size;2306 2307	ch->rsp_buf_cache = srpt_cache_get(ch->max_rsp_size);2308	if (!ch->rsp_buf_cache)2309		goto free_ch;2310 2311	ch->ioctx_ring = (struct srpt_send_ioctx **)2312		srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size,2313				      sizeof(*ch->ioctx_ring[0]),2314				      ch->rsp_buf_cache, 0, DMA_TO_DEVICE);2315	if (!ch->ioctx_ring) {2316		pr_err("rejected SRP_LOGIN_REQ because creating a new QP SQ ring failed.\n");2317		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2318		goto free_rsp_cache;2319	}2320 2321	for (i = 0; i < ch->rq_size; i++)2322		ch->ioctx_ring[i]->ch = ch;2323	if (!sdev->use_srq) {2324		u16 imm_data_offset = req->req_flags & SRP_IMMED_REQUESTED ?2325			be16_to_cpu(req->imm_data_offset) : 0;2326		u16 alignment_offset;2327		u32 req_sz;2328 2329		if (req->req_flags & SRP_IMMED_REQUESTED)2330			pr_debug("imm_data_offset = %d\n",2331				 be16_to_cpu(req->imm_data_offset));2332		if (imm_data_offset >= sizeof(struct srp_cmd)) {2333			ch->imm_data_offset = imm_data_offset;2334			rsp->rsp_flags |= SRP_LOGIN_RSP_IMMED_SUPP;2335		} else {2336			ch->imm_data_offset = 0;2337		}2338		alignment_offset = round_up(imm_data_offset, 512) -2339			imm_data_offset;2340		req_sz = alignment_offset + imm_data_offset + srp_max_req_size;2341		ch->req_buf_cache = srpt_cache_get(req_sz);2342		if (!ch->req_buf_cache)2343			goto free_rsp_ring;2344 2345		ch->ioctx_recv_ring = (struct srpt_recv_ioctx **)2346			srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size,2347					      sizeof(*ch->ioctx_recv_ring[0]),2348					      ch->req_buf_cache,2349					      alignment_offset,2350					      DMA_FROM_DEVICE);2351		if (!ch->ioctx_recv_ring) {2352			pr_err("rejected SRP_LOGIN_REQ because creating a new QP RQ ring failed.\n");2353			rej->reason =2354			    cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2355			goto free_recv_cache;2356		}2357		for (i = 0; i < ch->rq_size; i++)2358			INIT_LIST_HEAD(&ch->ioctx_recv_ring[i]->wait_list);2359	}2360 2361	ret = srpt_create_ch_ib(ch);2362	if (ret) {2363		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2364		pr_err("rejected SRP_LOGIN_REQ because creating a new RDMA channel failed.\n");2365		goto free_recv_ring;2366	}2367 2368	strscpy(ch->sess_name, src_addr, sizeof(ch->sess_name));2369	snprintf(i_port_id, sizeof(i_port_id), "0x%016llx%016llx",2370			be64_to_cpu(*(__be64 *)nexus->i_port_id),2371			be64_to_cpu(*(__be64 *)(nexus->i_port_id + 8)));2372 2373	pr_debug("registering src addr %s or i_port_id %s\n", ch->sess_name,2374		 i_port_id);2375 2376	tag_num = ch->rq_size;2377	tag_size = 1; /* ib_srpt does not use se_sess->sess_cmd_map */2378 2379	if (sport->guid_id) {2380		mutex_lock(&sport->guid_id->mutex);2381		list_for_each_entry(stpg, &sport->guid_id->tpg_list, entry) {2382			if (!IS_ERR_OR_NULL(ch->sess))2383				break;2384			ch->sess = target_setup_session(&stpg->tpg, tag_num,2385						tag_size, TARGET_PROT_NORMAL,2386						ch->sess_name, ch, NULL);2387		}2388		mutex_unlock(&sport->guid_id->mutex);2389	}2390 2391	if (sport->gid_id) {2392		mutex_lock(&sport->gid_id->mutex);2393		list_for_each_entry(stpg, &sport->gid_id->tpg_list, entry) {2394			if (!IS_ERR_OR_NULL(ch->sess))2395				break;2396			ch->sess = target_setup_session(&stpg->tpg, tag_num,2397					tag_size, TARGET_PROT_NORMAL, i_port_id,2398					ch, NULL);2399			if (!IS_ERR_OR_NULL(ch->sess))2400				break;2401			/* Retry without leading "0x" */2402			ch->sess = target_setup_session(&stpg->tpg, tag_num,2403						tag_size, TARGET_PROT_NORMAL,2404						i_port_id + 2, ch, NULL);2405		}2406		mutex_unlock(&sport->gid_id->mutex);2407	}2408 2409	if (IS_ERR_OR_NULL(ch->sess)) {2410		WARN_ON_ONCE(ch->sess == NULL);2411		ret = PTR_ERR(ch->sess);2412		ch->sess = NULL;2413		pr_info("Rejected login for initiator %s: ret = %d.\n",2414			ch->sess_name, ret);2415		rej->reason = cpu_to_be32(ret == -ENOMEM ?2416				SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES :2417				SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED);2418		goto destroy_ib;2419	}2420 2421	/*2422	 * Once a session has been created destruction of srpt_rdma_ch objects2423	 * will decrement sport->refcount. Hence increment sport->refcount now.2424	 */2425	atomic_inc(&sport->refcount);2426 2427	mutex_lock(&sport->mutex);2428 2429	if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) {2430		struct srpt_rdma_ch *ch2;2431 2432		list_for_each_entry(ch2, &nexus->ch_list, list) {2433			if (srpt_disconnect_ch(ch2) < 0)2434				continue;2435			pr_info("Relogin - closed existing channel %s\n",2436				ch2->sess_name);2437			rsp->rsp_flags |= SRP_LOGIN_RSP_MULTICHAN_TERMINATED;2438		}2439	} else {2440		rsp->rsp_flags |= SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;2441	}2442 2443	list_add_tail_rcu(&ch->list, &nexus->ch_list);2444 2445	if (!sport->enabled) {2446		rej->reason = cpu_to_be32(2447				SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2448		pr_info("rejected SRP_LOGIN_REQ because target %s_%d is not enabled\n",2449			dev_name(&sdev->device->dev), port_num);2450		mutex_unlock(&sport->mutex);2451		ret = -EINVAL;2452		goto reject;2453	}2454 2455	mutex_unlock(&sport->mutex);2456 2457	ret = ch->using_rdma_cm ? 0 : srpt_ch_qp_rtr(ch, ch->qp);2458	if (ret) {2459		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2460		pr_err("rejected SRP_LOGIN_REQ because enabling RTR failed (error code = %d)\n",2461		       ret);2462		goto reject;2463	}2464 2465	pr_debug("Establish connection sess=%p name=%s ch=%p\n", ch->sess,2466		 ch->sess_name, ch);2467 2468	/* create srp_login_response */2469	rsp->opcode = SRP_LOGIN_RSP;2470	rsp->tag = req->tag;2471	rsp->max_it_iu_len = cpu_to_be32(srp_max_req_size);2472	rsp->max_ti_iu_len = req->req_it_iu_len;2473	ch->max_ti_iu_len = it_iu_len;2474	rsp->buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |2475				   SRP_BUF_FORMAT_INDIRECT);2476	rsp->req_lim_delta = cpu_to_be32(ch->rq_size);2477	atomic_set(&ch->req_lim, ch->rq_size);2478	atomic_set(&ch->req_lim_delta, 0);2479 2480	/* create cm reply */2481	if (ch->using_rdma_cm) {2482		rep_param->rdma_cm.private_data = (void *)rsp;2483		rep_param->rdma_cm.private_data_len = sizeof(*rsp);2484		rep_param->rdma_cm.rnr_retry_count = 7;2485		rep_param->rdma_cm.flow_control = 1;2486		rep_param->rdma_cm.responder_resources = 4;2487		rep_param->rdma_cm.initiator_depth = 4;2488	} else {2489		rep_param->ib_cm.qp_num = ch->qp->qp_num;2490		rep_param->ib_cm.private_data = (void *)rsp;2491		rep_param->ib_cm.private_data_len = sizeof(*rsp);2492		rep_param->ib_cm.rnr_retry_count = 7;2493		rep_param->ib_cm.flow_control = 1;2494		rep_param->ib_cm.failover_accepted = 0;2495		rep_param->ib_cm.srq = 1;2496		rep_param->ib_cm.responder_resources = 4;2497		rep_param->ib_cm.initiator_depth = 4;2498	}2499 2500	/*2501	 * Hold the sport mutex while accepting a connection to avoid that2502	 * srpt_disconnect_ch() is invoked concurrently with this code.2503	 */2504	mutex_lock(&sport->mutex);2505	if (sport->enabled && ch->state == CH_CONNECTING) {2506		if (ch->using_rdma_cm)2507			ret = rdma_accept(rdma_cm_id, &rep_param->rdma_cm);2508		else2509			ret = ib_send_cm_rep(ib_cm_id, &rep_param->ib_cm);2510	} else {2511		ret = -EINVAL;2512	}2513	mutex_unlock(&sport->mutex);2514 2515	switch (ret) {2516	case 0:2517		break;2518	case -EINVAL:2519		goto reject;2520	default:2521		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);2522		pr_err("sending SRP_LOGIN_REQ response failed (error code = %d)\n",2523		       ret);2524		goto reject;2525	}2526 2527	goto out;2528 2529destroy_ib:2530	srpt_destroy_ch_ib(ch);2531 2532free_recv_ring:2533	srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_recv_ring,2534			     ch->sport->sdev, ch->rq_size,2535			     ch->req_buf_cache, DMA_FROM_DEVICE);2536 2537free_recv_cache:2538	srpt_cache_put(ch->req_buf_cache);2539 2540free_rsp_ring:2541	srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,2542			     ch->sport->sdev, ch->rq_size,2543			     ch->rsp_buf_cache, DMA_TO_DEVICE);2544 2545free_rsp_cache:2546	srpt_cache_put(ch->rsp_buf_cache);2547 2548free_ch:2549	if (rdma_cm_id)2550		rdma_cm_id->context = NULL;2551	else2552		ib_cm_id->context = NULL;2553	kfree(ch);2554	ch = NULL;2555 2556	WARN_ON_ONCE(ret == 0);2557 2558reject:2559	pr_info("Rejecting login with reason %#x\n", be32_to_cpu(rej->reason));2560	rej->opcode = SRP_LOGIN_REJ;2561	rej->tag = req->tag;2562	rej->buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |2563				   SRP_BUF_FORMAT_INDIRECT);2564 2565	if (rdma_cm_id)2566		rdma_reject(rdma_cm_id, rej, sizeof(*rej),2567			    IB_CM_REJ_CONSUMER_DEFINED);2568	else2569		ib_send_cm_rej(ib_cm_id, IB_CM_REJ_CONSUMER_DEFINED, NULL, 0,2570			       rej, sizeof(*rej));2571 2572	if (ch && ch->sess) {2573		srpt_close_ch(ch);2574		/*2575		 * Tell the caller not to free cm_id since2576		 * srpt_release_channel_work() will do that.2577		 */2578		ret = 0;2579	}2580 2581out:2582	kfree(rep_param);2583	kfree(rsp);2584	kfree(rej);2585 2586	return ret;2587}2588 2589static int srpt_ib_cm_req_recv(struct ib_cm_id *cm_id,2590			       const struct ib_cm_req_event_param *param,2591			       void *private_data)2592{2593	char sguid[40];2594 2595	srpt_format_guid(sguid, sizeof(sguid),2596			 &param->primary_path->dgid.global.interface_id);2597 2598	return srpt_cm_req_recv(cm_id->context, cm_id, NULL, param->port,2599				param->primary_path->pkey,2600				private_data, sguid);2601}2602 2603static int srpt_rdma_cm_req_recv(struct rdma_cm_id *cm_id,2604				 struct rdma_cm_event *event)2605{2606	struct srpt_device *sdev;2607	struct srp_login_req req;2608	const struct srp_login_req_rdma *req_rdma;2609	struct sa_path_rec *path_rec = cm_id->route.path_rec;2610	char src_addr[40];2611 2612	sdev = ib_get_client_data(cm_id->device, &srpt_client);2613	if (!sdev)2614		return -ECONNREFUSED;2615 2616	if (event->param.conn.private_data_len < sizeof(*req_rdma))2617		return -EINVAL;2618 2619	/* Transform srp_login_req_rdma into srp_login_req. */2620	req_rdma = event->param.conn.private_data;2621	memset(&req, 0, sizeof(req));2622	req.opcode		= req_rdma->opcode;2623	req.tag			= req_rdma->tag;2624	req.req_it_iu_len	= req_rdma->req_it_iu_len;2625	req.req_buf_fmt		= req_rdma->req_buf_fmt;2626	req.req_flags		= req_rdma->req_flags;2627	memcpy(req.initiator_port_id, req_rdma->initiator_port_id, 16);2628	memcpy(req.target_port_id, req_rdma->target_port_id, 16);2629	req.imm_data_offset	= req_rdma->imm_data_offset;2630 2631	snprintf(src_addr, sizeof(src_addr), "%pIS",2632		 &cm_id->route.addr.src_addr);2633 2634	return srpt_cm_req_recv(sdev, NULL, cm_id, cm_id->port_num,2635				path_rec ? path_rec->pkey : 0, &req, src_addr);2636}2637 2638static void srpt_cm_rej_recv(struct srpt_rdma_ch *ch,2639			     enum ib_cm_rej_reason reason,2640			     const u8 *private_data,2641			     u8 private_data_len)2642{2643	char *priv = NULL;2644	int i;2645 2646	if (private_data_len && (priv = kmalloc(private_data_len * 3 + 1,2647						GFP_KERNEL))) {2648		for (i = 0; i < private_data_len; i++)2649			sprintf(priv + 3 * i, " %02x", private_data[i]);2650	}2651	pr_info("Received CM REJ for ch %s-%d; reason %d%s%s.\n",2652		ch->sess_name, ch->qp->qp_num, reason, private_data_len ?2653		"; private data" : "", priv ? priv : " (?)");2654	kfree(priv);2655}2656 2657/**2658 * srpt_cm_rtu_recv - process an IB_CM_RTU_RECEIVED or USER_ESTABLISHED event2659 * @ch: SRPT RDMA channel.2660 *2661 * An RTU (ready to use) message indicates that the connection has been2662 * established and that the recipient may begin transmitting.2663 */2664static void srpt_cm_rtu_recv(struct srpt_rdma_ch *ch)2665{2666	int ret;2667 2668	ret = ch->using_rdma_cm ? 0 : srpt_ch_qp_rts(ch, ch->qp);2669	if (ret < 0) {2670		pr_err("%s-%d: QP transition to RTS failed\n", ch->sess_name,2671		       ch->qp->qp_num);2672		srpt_close_ch(ch);2673		return;2674	}2675 2676	/*2677	 * Note: calling srpt_close_ch() if the transition to the LIVE state2678	 * fails is not necessary since that means that that function has2679	 * already been invoked from another thread.2680	 */2681	if (!srpt_set_ch_state(ch, CH_LIVE)) {2682		pr_err("%s-%d: channel transition to LIVE state failed\n",2683		       ch->sess_name, ch->qp->qp_num);2684		return;2685	}2686 2687	/* Trigger wait list processing. */2688	ret = srpt_zerolength_write(ch);2689	WARN_ONCE(ret < 0, "%d\n", ret);2690}2691 2692/**2693 * srpt_cm_handler - IB connection manager callback function2694 * @cm_id: IB/CM connection identifier.2695 * @event: IB/CM event.2696 *2697 * A non-zero return value will cause the caller destroy the CM ID.2698 *2699 * Note: srpt_cm_handler() must only return a non-zero value when transferring2700 * ownership of the cm_id to a channel by srpt_cm_req_recv() failed. Returning2701 * a non-zero value in any other case will trigger a race with the2702 * ib_destroy_cm_id() call in srpt_release_channel().2703 */2704static int srpt_cm_handler(struct ib_cm_id *cm_id,2705			   const struct ib_cm_event *event)2706{2707	struct srpt_rdma_ch *ch = cm_id->context;2708	int ret;2709 2710	ret = 0;2711	switch (event->event) {2712	case IB_CM_REQ_RECEIVED:2713		ret = srpt_ib_cm_req_recv(cm_id, &event->param.req_rcvd,2714					  event->private_data);2715		break;2716	case IB_CM_REJ_RECEIVED:2717		srpt_cm_rej_recv(ch, event->param.rej_rcvd.reason,2718				 event->private_data,2719				 IB_CM_REJ_PRIVATE_DATA_SIZE);2720		break;2721	case IB_CM_RTU_RECEIVED:2722	case IB_CM_USER_ESTABLISHED:2723		srpt_cm_rtu_recv(ch);2724		break;2725	case IB_CM_DREQ_RECEIVED:2726		srpt_disconnect_ch(ch);2727		break;2728	case IB_CM_DREP_RECEIVED:2729		pr_info("Received CM DREP message for ch %s-%d.\n",2730			ch->sess_name, ch->qp->qp_num);2731		srpt_close_ch(ch);2732		break;2733	case IB_CM_TIMEWAIT_EXIT:2734		pr_info("Received CM TimeWait exit for ch %s-%d.\n",2735			ch->sess_name, ch->qp->qp_num);2736		srpt_close_ch(ch);2737		break;2738	case IB_CM_REP_ERROR:2739		pr_info("Received CM REP error for ch %s-%d.\n", ch->sess_name,2740			ch->qp->qp_num);2741		break;2742	case IB_CM_DREQ_ERROR:2743		pr_info("Received CM DREQ ERROR event.\n");2744		break;2745	case IB_CM_MRA_RECEIVED:2746		pr_info("Received CM MRA event\n");2747		break;2748	default:2749		pr_err("received unrecognized CM event %d\n", event->event);2750		break;2751	}2752 2753	return ret;2754}2755 2756static int srpt_rdma_cm_handler(struct rdma_cm_id *cm_id,2757				struct rdma_cm_event *event)2758{2759	struct srpt_rdma_ch *ch = cm_id->context;2760	int ret = 0;2761 2762	switch (event->event) {2763	case RDMA_CM_EVENT_CONNECT_REQUEST:2764		ret = srpt_rdma_cm_req_recv(cm_id, event);2765		break;2766	case RDMA_CM_EVENT_REJECTED:2767		srpt_cm_rej_recv(ch, event->status,2768				 event->param.conn.private_data,2769				 event->param.conn.private_data_len);2770		break;2771	case RDMA_CM_EVENT_ESTABLISHED:2772		srpt_cm_rtu_recv(ch);2773		break;2774	case RDMA_CM_EVENT_DISCONNECTED:2775		if (ch->state < CH_DISCONNECTING)2776			srpt_disconnect_ch(ch);2777		else2778			srpt_close_ch(ch);2779		break;2780	case RDMA_CM_EVENT_TIMEWAIT_EXIT:2781		srpt_close_ch(ch);2782		break;2783	case RDMA_CM_EVENT_UNREACHABLE:2784		pr_info("Received CM REP error for ch %s-%d.\n", ch->sess_name,2785			ch->qp->qp_num);2786		break;2787	case RDMA_CM_EVENT_DEVICE_REMOVAL:2788	case RDMA_CM_EVENT_ADDR_CHANGE:2789		break;2790	default:2791		pr_err("received unrecognized RDMA CM event %d\n",2792		       event->event);2793		break;2794	}2795 2796	return ret;2797}2798 2799/*2800 * srpt_write_pending - Start data transfer from initiator to target (write).2801 */2802static int srpt_write_pending(struct se_cmd *se_cmd)2803{2804	struct srpt_send_ioctx *ioctx =2805		container_of(se_cmd, struct srpt_send_ioctx, cmd);2806	struct srpt_rdma_ch *ch = ioctx->ch;2807	struct ib_send_wr *first_wr = NULL;2808	struct ib_cqe *cqe = &ioctx->rdma_cqe;2809	enum srpt_command_state new_state;2810	int ret, i;2811 2812	if (ioctx->recv_ioctx) {2813		srpt_set_cmd_state(ioctx, SRPT_STATE_DATA_IN);2814		target_execute_cmd(&ioctx->cmd);2815		return 0;2816	}2817 2818	new_state = srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA);2819	WARN_ON(new_state == SRPT_STATE_DONE);2820 2821	if (atomic_sub_return(ioctx->n_rdma, &ch->sq_wr_avail) < 0) {2822		pr_warn("%s: IB send queue full (needed %d)\n",2823				__func__, ioctx->n_rdma);2824		ret = -ENOMEM;2825		goto out_undo;2826	}2827 2828	cqe->done = srpt_rdma_read_done;2829	for (i = ioctx->n_rw_ctx - 1; i >= 0; i--) {2830		struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i];2831 2832		first_wr = rdma_rw_ctx_wrs(&ctx->rw, ch->qp, ch->sport->port,2833				cqe, first_wr);2834		cqe = NULL;2835	}2836 2837	ret = ib_post_send(ch->qp, first_wr, NULL);2838	if (ret) {2839		pr_err("%s: ib_post_send() returned %d for %d (avail: %d)\n",2840			 __func__, ret, ioctx->n_rdma,2841			 atomic_read(&ch->sq_wr_avail));2842		goto out_undo;2843	}2844 2845	return 0;2846out_undo:2847	atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);2848	return ret;2849}2850 2851static u8 tcm_to_srp_tsk_mgmt_status(const int tcm_mgmt_status)2852{2853	switch (tcm_mgmt_status) {2854	case TMR_FUNCTION_COMPLETE:2855		return SRP_TSK_MGMT_SUCCESS;2856	case TMR_FUNCTION_REJECTED:2857		return SRP_TSK_MGMT_FUNC_NOT_SUPP;2858	}2859	return SRP_TSK_MGMT_FAILED;2860}2861 2862/**2863 * srpt_queue_response - transmit the response to a SCSI command2864 * @cmd: SCSI target command.2865 *2866 * Callback function called by the TCM core. Must not block since it can be2867 * invoked on the context of the IB completion handler.2868 */2869static void srpt_queue_response(struct se_cmd *cmd)2870{2871	struct srpt_send_ioctx *ioctx =2872		container_of(cmd, struct srpt_send_ioctx, cmd);2873	struct srpt_rdma_ch *ch = ioctx->ch;2874	struct srpt_device *sdev = ch->sport->sdev;2875	struct ib_send_wr send_wr, *first_wr = &send_wr;2876	struct ib_sge sge;2877	enum srpt_command_state state;2878	int resp_len, ret, i;2879	u8 srp_tm_status;2880 2881	state = ioctx->state;2882	switch (state) {2883	case SRPT_STATE_NEW:2884	case SRPT_STATE_DATA_IN:2885		ioctx->state = SRPT_STATE_CMD_RSP_SENT;2886		break;2887	case SRPT_STATE_MGMT:2888		ioctx->state = SRPT_STATE_MGMT_RSP_SENT;2889		break;2890	default:2891		WARN(true, "ch %p; cmd %d: unexpected command state %d\n",2892			ch, ioctx->ioctx.index, ioctx->state);2893		break;2894	}2895 2896	if (WARN_ON_ONCE(state == SRPT_STATE_CMD_RSP_SENT))2897		return;2898 2899	/* For read commands, transfer the data to the initiator. */2900	if (ioctx->cmd.data_direction == DMA_FROM_DEVICE &&2901	    ioctx->cmd.data_length &&2902	    !ioctx->queue_status_only) {2903		for (i = ioctx->n_rw_ctx - 1; i >= 0; i--) {2904			struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i];2905 2906			first_wr = rdma_rw_ctx_wrs(&ctx->rw, ch->qp,2907					ch->sport->port, NULL, first_wr);2908		}2909	}2910 2911	if (state != SRPT_STATE_MGMT)2912		resp_len = srpt_build_cmd_rsp(ch, ioctx, ioctx->cmd.tag,2913					      cmd->scsi_status);2914	else {2915		srp_tm_status2916			= tcm_to_srp_tsk_mgmt_status(cmd->se_tmr_req->response);2917		resp_len = srpt_build_tskmgmt_rsp(ch, ioctx, srp_tm_status,2918						 ioctx->cmd.tag);2919	}2920 2921	atomic_inc(&ch->req_lim);2922 2923	if (unlikely(atomic_sub_return(1 + ioctx->n_rdma,2924			&ch->sq_wr_avail) < 0)) {2925		pr_warn("%s: IB send queue full (needed %d)\n",2926				__func__, ioctx->n_rdma);2927		goto out;2928	}2929 2930	ib_dma_sync_single_for_device(sdev->device, ioctx->ioctx.dma, resp_len,2931				      DMA_TO_DEVICE);2932 2933	sge.addr = ioctx->ioctx.dma;2934	sge.length = resp_len;2935	sge.lkey = sdev->lkey;2936 2937	ioctx->ioctx.cqe.done = srpt_send_done;2938	send_wr.next = NULL;2939	send_wr.wr_cqe = &ioctx->ioctx.cqe;2940	send_wr.sg_list = &sge;2941	send_wr.num_sge = 1;2942	send_wr.opcode = IB_WR_SEND;2943	send_wr.send_flags = IB_SEND_SIGNALED;2944 2945	ret = ib_post_send(ch->qp, first_wr, NULL);2946	if (ret < 0) {2947		pr_err("%s: sending cmd response failed for tag %llu (%d)\n",2948			__func__, ioctx->cmd.tag, ret);2949		goto out;2950	}2951 2952	return;2953 2954out:2955	atomic_add(1 + ioctx->n_rdma, &ch->sq_wr_avail);2956	atomic_dec(&ch->req_lim);2957	srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);2958	target_put_sess_cmd(&ioctx->cmd);2959}2960 2961static int srpt_queue_data_in(struct se_cmd *cmd)2962{2963	srpt_queue_response(cmd);2964	return 0;2965}2966 2967static void srpt_queue_tm_rsp(struct se_cmd *cmd)2968{2969	srpt_queue_response(cmd);2970}2971 2972/*2973 * This function is called for aborted commands if no response is sent to the2974 * initiator. Make sure that the credits freed by aborting a command are2975 * returned to the initiator the next time a response is sent by incrementing2976 * ch->req_lim_delta.2977 */2978static void srpt_aborted_task(struct se_cmd *cmd)2979{2980	struct srpt_send_ioctx *ioctx = container_of(cmd,2981				struct srpt_send_ioctx, cmd);2982	struct srpt_rdma_ch *ch = ioctx->ch;2983 2984	atomic_inc(&ch->req_lim_delta);2985}2986 2987static int srpt_queue_status(struct se_cmd *cmd)2988{2989	struct srpt_send_ioctx *ioctx;2990 2991	ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);2992	BUG_ON(ioctx->sense_data != cmd->sense_buffer);2993	if (cmd->se_cmd_flags &2994	    (SCF_TRANSPORT_TASK_SENSE | SCF_EMULATED_TASK_SENSE))2995		WARN_ON(cmd->scsi_status != SAM_STAT_CHECK_CONDITION);2996	ioctx->queue_status_only = true;2997	srpt_queue_response(cmd);2998	return 0;2999}3000 3001static void srpt_refresh_port_work(struct work_struct *work)3002{3003	struct srpt_port *sport = container_of(work, struct srpt_port, work);3004 3005	srpt_refresh_port(sport);3006}3007 3008/**3009 * srpt_release_sport - disable login and wait for associated channels3010 * @sport: SRPT HCA port.3011 */3012static int srpt_release_sport(struct srpt_port *sport)3013{3014	DECLARE_COMPLETION_ONSTACK(c);3015	struct srpt_nexus *nexus, *next_n;3016	struct srpt_rdma_ch *ch;3017 3018	WARN_ON_ONCE(irqs_disabled());3019 3020	sport->freed_channels = &c;3021 3022	mutex_lock(&sport->mutex);3023	srpt_set_enabled(sport, false);3024	mutex_unlock(&sport->mutex);3025 3026	while (atomic_read(&sport->refcount) > 0 &&3027	       wait_for_completion_timeout(&c, 5 * HZ) <= 0) {3028		pr_info("%s_%d: waiting for unregistration of %d sessions ...\n",3029			dev_name(&sport->sdev->device->dev), sport->port,3030			atomic_read(&sport->refcount));3031		rcu_read_lock();3032		list_for_each_entry(nexus, &sport->nexus_list, entry) {3033			list_for_each_entry(ch, &nexus->ch_list, list) {3034				pr_info("%s-%d: state %s\n",3035					ch->sess_name, ch->qp->qp_num,3036					get_ch_state_name(ch->state));3037			}3038		}3039		rcu_read_unlock();3040	}3041 3042	mutex_lock(&sport->mutex);3043	list_for_each_entry_safe(nexus, next_n, &sport->nexus_list, entry) {3044		list_del(&nexus->entry);3045		kfree_rcu(nexus, rcu);3046	}3047	mutex_unlock(&sport->mutex);3048 3049	return 0;3050}3051 3052struct port_and_port_id {3053	struct srpt_port *sport;3054	struct srpt_port_id **port_id;3055};3056 3057static struct port_and_port_id __srpt_lookup_port(const char *name)3058{3059	struct ib_device *dev;3060	struct srpt_device *sdev;3061	struct srpt_port *sport;3062	int i;3063 3064	list_for_each_entry(sdev, &srpt_dev_list, list) {3065		dev = sdev->device;3066		if (!dev)3067			continue;3068 3069		for (i = 0; i < dev->phys_port_cnt; i++) {3070			sport = &sdev->port[i];3071 3072			if (strcmp(sport->guid_name, name) == 0) {3073				kref_get(&sdev->refcnt);3074				return (struct port_and_port_id){3075					sport, &sport->guid_id};3076			}3077			if (strcmp(sport->gid_name, name) == 0) {3078				kref_get(&sdev->refcnt);3079				return (struct port_and_port_id){3080					sport, &sport->gid_id};3081			}3082		}3083	}3084 3085	return (struct port_and_port_id){};3086}3087 3088/**3089 * srpt_lookup_port() - Look up an RDMA port by name3090 * @name: ASCII port name3091 *3092 * Increments the RDMA port reference count if an RDMA port pointer is returned.3093 * The caller must drop that reference count by calling srpt_port_put_ref().3094 */3095static struct port_and_port_id srpt_lookup_port(const char *name)3096{3097	struct port_and_port_id papi;3098 3099	spin_lock(&srpt_dev_lock);3100	papi = __srpt_lookup_port(name);3101	spin_unlock(&srpt_dev_lock);3102 3103	return papi;3104}3105 3106static void srpt_free_srq(struct srpt_device *sdev)3107{3108	if (!sdev->srq)3109		return;3110 3111	ib_destroy_srq(sdev->srq);3112	srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,3113			     sdev->srq_size, sdev->req_buf_cache,3114			     DMA_FROM_DEVICE);3115	srpt_cache_put(sdev->req_buf_cache);3116	sdev->srq = NULL;3117}3118 3119static int srpt_alloc_srq(struct srpt_device *sdev)3120{3121	struct ib_srq_init_attr srq_attr = {3122		.event_handler = srpt_srq_event,3123		.srq_context = (void *)sdev,3124		.attr.max_wr = sdev->srq_size,3125		.attr.max_sge = 1,3126		.srq_type = IB_SRQT_BASIC,3127	};3128	struct ib_device *device = sdev->device;3129	struct ib_srq *srq;3130	int i;3131 3132	WARN_ON_ONCE(sdev->srq);3133	srq = ib_create_srq(sdev->pd, &srq_attr);3134	if (IS_ERR(srq)) {3135		pr_debug("ib_create_srq() failed: %ld\n", PTR_ERR(srq));3136		return PTR_ERR(srq);3137	}3138 3139	pr_debug("create SRQ #wr= %d max_allow=%d dev= %s\n", sdev->srq_size,3140		 sdev->device->attrs.max_srq_wr, dev_name(&device->dev));3141 3142	sdev->req_buf_cache = srpt_cache_get(srp_max_req_size);3143	if (!sdev->req_buf_cache)3144		goto free_srq;3145 3146	sdev->ioctx_ring = (struct srpt_recv_ioctx **)3147		srpt_alloc_ioctx_ring(sdev, sdev->srq_size,3148				      sizeof(*sdev->ioctx_ring[0]),3149				      sdev->req_buf_cache, 0, DMA_FROM_DEVICE);3150	if (!sdev->ioctx_ring)3151		goto free_cache;3152 3153	sdev->use_srq = true;3154	sdev->srq = srq;3155 3156	for (i = 0; i < sdev->srq_size; ++i) {3157		INIT_LIST_HEAD(&sdev->ioctx_ring[i]->wait_list);3158		srpt_post_recv(sdev, NULL, sdev->ioctx_ring[i]);3159	}3160 3161	return 0;3162 3163free_cache:3164	srpt_cache_put(sdev->req_buf_cache);3165 3166free_srq:3167	ib_destroy_srq(srq);3168	return -ENOMEM;3169}3170 3171static int srpt_use_srq(struct srpt_device *sdev, bool use_srq)3172{3173	struct ib_device *device = sdev->device;3174	int ret = 0;3175 3176	if (!use_srq) {3177		srpt_free_srq(sdev);3178		sdev->use_srq = false;3179	} else if (use_srq && !sdev->srq) {3180		ret = srpt_alloc_srq(sdev);3181	}3182	pr_debug("%s(%s): use_srq = %d; ret = %d\n", __func__,3183		 dev_name(&device->dev), sdev->use_srq, ret);3184	return ret;3185}3186 3187static void srpt_free_sdev(struct kref *refcnt)3188{3189	struct srpt_device *sdev = container_of(refcnt, typeof(*sdev), refcnt);3190 3191	kfree(sdev);3192}3193 3194static void srpt_sdev_put(struct srpt_device *sdev)3195{3196	kref_put(&sdev->refcnt, srpt_free_sdev);3197}3198 3199/**3200 * srpt_add_one - InfiniBand device addition callback function3201 * @device: Describes a HCA.3202 */3203static int srpt_add_one(struct ib_device *device)3204{3205	struct srpt_device *sdev;3206	struct srpt_port *sport;3207	int ret;3208	u32 i;3209 3210	pr_debug("device = %p\n", device);3211 3212	sdev = kzalloc(struct_size(sdev, port, device->phys_port_cnt),3213		       GFP_KERNEL);3214	if (!sdev)3215		return -ENOMEM;3216 3217	kref_init(&sdev->refcnt);3218	sdev->device = device;3219	mutex_init(&sdev->sdev_mutex);3220 3221	sdev->pd = ib_alloc_pd(device, 0);3222	if (IS_ERR(sdev->pd)) {3223		ret = PTR_ERR(sdev->pd);3224		goto free_dev;3225	}3226 3227	sdev->lkey = sdev->pd->local_dma_lkey;3228 3229	sdev->srq_size = min(srpt_srq_size, sdev->device->attrs.max_srq_wr);3230 3231	srpt_use_srq(sdev, sdev->port[0].port_attrib.use_srq);3232 3233	if (!srpt_service_guid)3234		srpt_service_guid = be64_to_cpu(device->node_guid);3235 3236	if (rdma_port_get_link_layer(device, 1) == IB_LINK_LAYER_INFINIBAND)3237		sdev->cm_id = ib_create_cm_id(device, srpt_cm_handler, sdev);3238	if (IS_ERR(sdev->cm_id)) {3239		pr_info("ib_create_cm_id() failed: %ld\n",3240			PTR_ERR(sdev->cm_id));3241		ret = PTR_ERR(sdev->cm_id);3242		sdev->cm_id = NULL;3243		if (!rdma_cm_id)3244			goto err_ring;3245	}3246 3247	/* print out target login information */3248	pr_debug("Target login info: id_ext=%016llx,ioc_guid=%016llx,pkey=ffff,service_id=%016llx\n",3249		 srpt_service_guid, srpt_service_guid, srpt_service_guid);3250 3251	/*3252	 * We do not have a consistent service_id (ie. also id_ext of target_id)3253	 * to identify this target. We currently use the guid of the first HCA3254	 * in the system as service_id; therefore, the target_id will change3255	 * if this HCA is gone bad and replaced by different HCA3256	 */3257	ret = sdev->cm_id ?3258		ib_cm_listen(sdev->cm_id, cpu_to_be64(srpt_service_guid)) :3259		0;3260	if (ret < 0) {3261		pr_err("ib_cm_listen() failed: %d (cm_id state = %d)\n", ret,3262		       sdev->cm_id->state);3263		goto err_cm;3264	}3265 3266	INIT_IB_EVENT_HANDLER(&sdev->event_handler, sdev->device,3267			      srpt_event_handler);3268 3269	for (i = 1; i <= sdev->device->phys_port_cnt; i++) {3270		sport = &sdev->port[i - 1];3271		INIT_LIST_HEAD(&sport->nexus_list);3272		mutex_init(&sport->mutex);3273		sport->sdev = sdev;3274		sport->port = i;3275		sport->port_attrib.srp_max_rdma_size = DEFAULT_MAX_RDMA_SIZE;3276		sport->port_attrib.srp_max_rsp_size = DEFAULT_MAX_RSP_SIZE;3277		sport->port_attrib.srp_sq_size = DEF_SRPT_SQ_SIZE;3278		sport->port_attrib.use_srq = false;3279		INIT_WORK(&sport->work, srpt_refresh_port_work);3280 3281		ret = srpt_refresh_port(sport);3282		if (ret) {3283			pr_err("MAD registration failed for %s-%d.\n",3284			       dev_name(&sdev->device->dev), i);3285			i--;3286			goto err_port;3287		}3288	}3289 3290	ib_register_event_handler(&sdev->event_handler);3291	spin_lock(&srpt_dev_lock);3292	list_add_tail(&sdev->list, &srpt_dev_list);3293	spin_unlock(&srpt_dev_lock);3294 3295	ib_set_client_data(device, &srpt_client, sdev);3296	pr_debug("added %s.\n", dev_name(&device->dev));3297	return 0;3298 3299err_port:3300	srpt_unregister_mad_agent(sdev, i);3301err_cm:3302	if (sdev->cm_id)3303		ib_destroy_cm_id(sdev->cm_id);3304err_ring:3305	srpt_free_srq(sdev);3306	ib_dealloc_pd(sdev->pd);3307free_dev:3308	srpt_sdev_put(sdev);3309	pr_info("%s(%s) failed.\n", __func__, dev_name(&device->dev));3310	return ret;3311}3312 3313/**3314 * srpt_remove_one - InfiniBand device removal callback function3315 * @device: Describes a HCA.3316 * @client_data: The value passed as the third argument to ib_set_client_data().3317 */3318static void srpt_remove_one(struct ib_device *device, void *client_data)3319{3320	struct srpt_device *sdev = client_data;3321	int i;3322 3323	srpt_unregister_mad_agent(sdev, sdev->device->phys_port_cnt);3324 3325	ib_unregister_event_handler(&sdev->event_handler);3326 3327	/* Cancel any work queued by the just unregistered IB event handler. */3328	for (i = 0; i < sdev->device->phys_port_cnt; i++)3329		cancel_work_sync(&sdev->port[i].work);3330 3331	if (sdev->cm_id)3332		ib_destroy_cm_id(sdev->cm_id);3333 3334	ib_set_client_data(device, &srpt_client, NULL);3335 3336	/*3337	 * Unregistering a target must happen after destroying sdev->cm_id3338	 * such that no new SRP_LOGIN_REQ information units can arrive while3339	 * destroying the target.3340	 */3341	spin_lock(&srpt_dev_lock);3342	list_del(&sdev->list);3343	spin_unlock(&srpt_dev_lock);3344 3345	for (i = 0; i < sdev->device->phys_port_cnt; i++)3346		srpt_release_sport(&sdev->port[i]);3347 3348	srpt_free_srq(sdev);3349 3350	ib_dealloc_pd(sdev->pd);3351 3352	srpt_sdev_put(sdev);3353}3354 3355static struct ib_client srpt_client = {3356	.name = DRV_NAME,3357	.add = srpt_add_one,3358	.remove = srpt_remove_one3359};3360 3361static int srpt_check_true(struct se_portal_group *se_tpg)3362{3363	return 1;3364}3365 3366static struct srpt_port *srpt_tpg_to_sport(struct se_portal_group *tpg)3367{3368	return tpg->se_tpg_wwn->priv;3369}3370 3371static struct srpt_port_id *srpt_wwn_to_sport_id(struct se_wwn *wwn)3372{3373	struct srpt_port *sport = wwn->priv;3374 3375	if (sport->guid_id && &sport->guid_id->wwn == wwn)3376		return sport->guid_id;3377	if (sport->gid_id && &sport->gid_id->wwn == wwn)3378		return sport->gid_id;3379	WARN_ON_ONCE(true);3380	return NULL;3381}3382 3383static char *srpt_get_fabric_wwn(struct se_portal_group *tpg)3384{3385	struct srpt_tpg *stpg = container_of(tpg, typeof(*stpg), tpg);3386 3387	return stpg->sport_id->name;3388}3389 3390static u16 srpt_get_tag(struct se_portal_group *tpg)3391{3392	return 1;3393}3394 3395static void srpt_release_cmd(struct se_cmd *se_cmd)3396{3397	struct srpt_send_ioctx *ioctx = container_of(se_cmd,3398				struct srpt_send_ioctx, cmd);3399	struct srpt_rdma_ch *ch = ioctx->ch;3400	struct srpt_recv_ioctx *recv_ioctx = ioctx->recv_ioctx;3401 3402	WARN_ON_ONCE(ioctx->state != SRPT_STATE_DONE &&3403		     !(ioctx->cmd.transport_state & CMD_T_ABORTED));3404 3405	if (recv_ioctx) {3406		WARN_ON_ONCE(!list_empty(&recv_ioctx->wait_list));3407		ioctx->recv_ioctx = NULL;3408		srpt_post_recv(ch->sport->sdev, ch, recv_ioctx);3409	}3410 3411	if (ioctx->n_rw_ctx) {3412		srpt_free_rw_ctxs(ch, ioctx);3413		ioctx->n_rw_ctx = 0;3414	}3415 3416	target_free_tag(se_cmd->se_sess, se_cmd);3417}3418 3419/**3420 * srpt_close_session - forcibly close a session3421 * @se_sess: SCSI target session.3422 *3423 * Callback function invoked by the TCM core to clean up sessions associated3424 * with a node ACL when the user invokes3425 * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id3426 */3427static void srpt_close_session(struct se_session *se_sess)3428{3429	struct srpt_rdma_ch *ch = se_sess->fabric_sess_ptr;3430 3431	srpt_disconnect_ch_sync(ch);3432}3433 3434/* Note: only used from inside debug printk's by the TCM core. */3435static int srpt_get_tcm_cmd_state(struct se_cmd *se_cmd)3436{3437	struct srpt_send_ioctx *ioctx;3438 3439	ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);3440	return ioctx->state;3441}3442 3443static int srpt_parse_guid(u64 *guid, const char *name)3444{3445	u16 w[4];3446	int ret = -EINVAL;3447 3448	if (sscanf(name, "%hx:%hx:%hx:%hx", &w[0], &w[1], &w[2], &w[3]) != 4)3449		goto out;3450	*guid = get_unaligned_be64(w);3451	ret = 0;3452out:3453	return ret;3454}3455 3456/**3457 * srpt_parse_i_port_id - parse an initiator port ID3458 * @name: ASCII representation of a 128-bit initiator port ID.3459 * @i_port_id: Binary 128-bit port ID.3460 */3461static int srpt_parse_i_port_id(u8 i_port_id[16], const char *name)3462{3463	const char *p;3464	unsigned len, count, leading_zero_bytes;3465	int ret;3466 3467	p = name;3468	if (strncasecmp(p, "0x", 2) == 0)3469		p += 2;3470	ret = -EINVAL;3471	len = strlen(p);3472	if (len % 2)3473		goto out;3474	count = min(len / 2, 16U);3475	leading_zero_bytes = 16 - count;3476	memset(i_port_id, 0, leading_zero_bytes);3477	ret = hex2bin(i_port_id + leading_zero_bytes, p, count);3478 3479out:3480	return ret;3481}3482 3483/*3484 * configfs callback function invoked for mkdir3485 * /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id3486 *3487 * i_port_id must be an initiator port GUID, GID or IP address. See also the3488 * target_alloc_session() calls in this driver. Examples of valid initiator3489 * port IDs:3490 * 0x0000000000000000505400fffe4a0b7b3491 * 0000000000000000505400fffe4a0b7b3492 * 5054:00ff:fe4a:0b7b3493 * 192.168.122.763494 */3495static int srpt_init_nodeacl(struct se_node_acl *se_nacl, const char *name)3496{3497	struct sockaddr_storage sa;3498	u64 guid;3499	u8 i_port_id[16];3500	int ret;3501 3502	ret = srpt_parse_guid(&guid, name);3503	if (ret < 0)3504		ret = srpt_parse_i_port_id(i_port_id, name);3505	if (ret < 0)3506		ret = inet_pton_with_scope(&init_net, AF_UNSPEC, name, NULL,3507					   &sa);3508	if (ret < 0)3509		pr_err("invalid initiator port ID %s\n", name);3510	return ret;3511}3512 3513static ssize_t srpt_tpg_attrib_srp_max_rdma_size_show(struct config_item *item,3514		char *page)3515{3516	struct se_portal_group *se_tpg = attrib_to_tpg(item);3517	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3518 3519	return sysfs_emit(page, "%u\n", sport->port_attrib.srp_max_rdma_size);3520}3521 3522static ssize_t srpt_tpg_attrib_srp_max_rdma_size_store(struct config_item *item,3523		const char *page, size_t count)3524{3525	struct se_portal_group *se_tpg = attrib_to_tpg(item);3526	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3527	unsigned long val;3528	int ret;3529 3530	ret = kstrtoul(page, 0, &val);3531	if (ret < 0) {3532		pr_err("kstrtoul() failed with ret: %d\n", ret);3533		return -EINVAL;3534	}3535	if (val > MAX_SRPT_RDMA_SIZE) {3536		pr_err("val: %lu exceeds MAX_SRPT_RDMA_SIZE: %d\n", val,3537			MAX_SRPT_RDMA_SIZE);3538		return -EINVAL;3539	}3540	if (val < DEFAULT_MAX_RDMA_SIZE) {3541		pr_err("val: %lu smaller than DEFAULT_MAX_RDMA_SIZE: %d\n",3542			val, DEFAULT_MAX_RDMA_SIZE);3543		return -EINVAL;3544	}3545	sport->port_attrib.srp_max_rdma_size = val;3546 3547	return count;3548}3549 3550static ssize_t srpt_tpg_attrib_srp_max_rsp_size_show(struct config_item *item,3551		char *page)3552{3553	struct se_portal_group *se_tpg = attrib_to_tpg(item);3554	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3555 3556	return sysfs_emit(page, "%u\n", sport->port_attrib.srp_max_rsp_size);3557}3558 3559static ssize_t srpt_tpg_attrib_srp_max_rsp_size_store(struct config_item *item,3560		const char *page, size_t count)3561{3562	struct se_portal_group *se_tpg = attrib_to_tpg(item);3563	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3564	unsigned long val;3565	int ret;3566 3567	ret = kstrtoul(page, 0, &val);3568	if (ret < 0) {3569		pr_err("kstrtoul() failed with ret: %d\n", ret);3570		return -EINVAL;3571	}3572	if (val > MAX_SRPT_RSP_SIZE) {3573		pr_err("val: %lu exceeds MAX_SRPT_RSP_SIZE: %d\n", val,3574			MAX_SRPT_RSP_SIZE);3575		return -EINVAL;3576	}3577	if (val < MIN_MAX_RSP_SIZE) {3578		pr_err("val: %lu smaller than MIN_MAX_RSP_SIZE: %d\n", val,3579			MIN_MAX_RSP_SIZE);3580		return -EINVAL;3581	}3582	sport->port_attrib.srp_max_rsp_size = val;3583 3584	return count;3585}3586 3587static ssize_t srpt_tpg_attrib_srp_sq_size_show(struct config_item *item,3588		char *page)3589{3590	struct se_portal_group *se_tpg = attrib_to_tpg(item);3591	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3592 3593	return sysfs_emit(page, "%u\n", sport->port_attrib.srp_sq_size);3594}3595 3596static ssize_t srpt_tpg_attrib_srp_sq_size_store(struct config_item *item,3597		const char *page, size_t count)3598{3599	struct se_portal_group *se_tpg = attrib_to_tpg(item);3600	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3601	unsigned long val;3602	int ret;3603 3604	ret = kstrtoul(page, 0, &val);3605	if (ret < 0) {3606		pr_err("kstrtoul() failed with ret: %d\n", ret);3607		return -EINVAL;3608	}3609	if (val > MAX_SRPT_SRQ_SIZE) {3610		pr_err("val: %lu exceeds MAX_SRPT_SRQ_SIZE: %d\n", val,3611			MAX_SRPT_SRQ_SIZE);3612		return -EINVAL;3613	}3614	if (val < MIN_SRPT_SRQ_SIZE) {3615		pr_err("val: %lu smaller than MIN_SRPT_SRQ_SIZE: %d\n", val,3616			MIN_SRPT_SRQ_SIZE);3617		return -EINVAL;3618	}3619	sport->port_attrib.srp_sq_size = val;3620 3621	return count;3622}3623 3624static ssize_t srpt_tpg_attrib_use_srq_show(struct config_item *item,3625					    char *page)3626{3627	struct se_portal_group *se_tpg = attrib_to_tpg(item);3628	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3629 3630	return sysfs_emit(page, "%d\n", sport->port_attrib.use_srq);3631}3632 3633static ssize_t srpt_tpg_attrib_use_srq_store(struct config_item *item,3634					     const char *page, size_t count)3635{3636	struct se_portal_group *se_tpg = attrib_to_tpg(item);3637	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3638	struct srpt_device *sdev = sport->sdev;3639	unsigned long val;3640	bool enabled;3641	int ret;3642 3643	ret = kstrtoul(page, 0, &val);3644	if (ret < 0)3645		return ret;3646	if (val != !!val)3647		return -EINVAL;3648 3649	ret = mutex_lock_interruptible(&sdev->sdev_mutex);3650	if (ret < 0)3651		return ret;3652	ret = mutex_lock_interruptible(&sport->mutex);3653	if (ret < 0)3654		goto unlock_sdev;3655	enabled = sport->enabled;3656	/* Log out all initiator systems before changing 'use_srq'. */3657	srpt_set_enabled(sport, false);3658	sport->port_attrib.use_srq = val;3659	srpt_use_srq(sdev, sport->port_attrib.use_srq);3660	srpt_set_enabled(sport, enabled);3661	ret = count;3662	mutex_unlock(&sport->mutex);3663unlock_sdev:3664	mutex_unlock(&sdev->sdev_mutex);3665 3666	return ret;3667}3668 3669CONFIGFS_ATTR(srpt_tpg_attrib_,  srp_max_rdma_size);3670CONFIGFS_ATTR(srpt_tpg_attrib_,  srp_max_rsp_size);3671CONFIGFS_ATTR(srpt_tpg_attrib_,  srp_sq_size);3672CONFIGFS_ATTR(srpt_tpg_attrib_,  use_srq);3673 3674static struct configfs_attribute *srpt_tpg_attrib_attrs[] = {3675	&srpt_tpg_attrib_attr_srp_max_rdma_size,3676	&srpt_tpg_attrib_attr_srp_max_rsp_size,3677	&srpt_tpg_attrib_attr_srp_sq_size,3678	&srpt_tpg_attrib_attr_use_srq,3679	NULL,3680};3681 3682static struct rdma_cm_id *srpt_create_rdma_id(struct sockaddr *listen_addr)3683{3684	struct rdma_cm_id *rdma_cm_id;3685	int ret;3686 3687	rdma_cm_id = rdma_create_id(&init_net, srpt_rdma_cm_handler,3688				    NULL, RDMA_PS_TCP, IB_QPT_RC);3689	if (IS_ERR(rdma_cm_id)) {3690		pr_err("RDMA/CM ID creation failed: %ld\n",3691		       PTR_ERR(rdma_cm_id));3692		goto out;3693	}3694 3695	ret = rdma_bind_addr(rdma_cm_id, listen_addr);3696	if (ret) {3697		char addr_str[64];3698 3699		snprintf(addr_str, sizeof(addr_str), "%pISp", listen_addr);3700		pr_err("Binding RDMA/CM ID to address %s failed: %d\n",3701		       addr_str, ret);3702		rdma_destroy_id(rdma_cm_id);3703		rdma_cm_id = ERR_PTR(ret);3704		goto out;3705	}3706 3707	ret = rdma_listen(rdma_cm_id, 128);3708	if (ret) {3709		pr_err("rdma_listen() failed: %d\n", ret);3710		rdma_destroy_id(rdma_cm_id);3711		rdma_cm_id = ERR_PTR(ret);3712	}3713 3714out:3715	return rdma_cm_id;3716}3717 3718static ssize_t srpt_rdma_cm_port_show(struct config_item *item, char *page)3719{3720	return sysfs_emit(page, "%d\n", rdma_cm_port);3721}3722 3723static ssize_t srpt_rdma_cm_port_store(struct config_item *item,3724				       const char *page, size_t count)3725{3726	struct sockaddr_in  addr4 = { .sin_family  = AF_INET  };3727	struct sockaddr_in6 addr6 = { .sin6_family = AF_INET6 };3728	struct rdma_cm_id *new_id = NULL;3729	u16 val;3730	int ret;3731 3732	ret = kstrtou16(page, 0, &val);3733	if (ret < 0)3734		return ret;3735	ret = count;3736	if (rdma_cm_port == val)3737		goto out;3738 3739	if (val) {3740		addr6.sin6_port = cpu_to_be16(val);3741		new_id = srpt_create_rdma_id((struct sockaddr *)&addr6);3742		if (IS_ERR(new_id)) {3743			addr4.sin_port = cpu_to_be16(val);3744			new_id = srpt_create_rdma_id((struct sockaddr *)&addr4);3745			if (IS_ERR(new_id)) {3746				ret = PTR_ERR(new_id);3747				goto out;3748			}3749		}3750	}3751 3752	mutex_lock(&rdma_cm_mutex);3753	rdma_cm_port = val;3754	swap(rdma_cm_id, new_id);3755	mutex_unlock(&rdma_cm_mutex);3756 3757	if (new_id)3758		rdma_destroy_id(new_id);3759	ret = count;3760out:3761	return ret;3762}3763 3764CONFIGFS_ATTR(srpt_, rdma_cm_port);3765 3766static struct configfs_attribute *srpt_da_attrs[] = {3767	&srpt_attr_rdma_cm_port,3768	NULL,3769};3770 3771static int srpt_enable_tpg(struct se_portal_group *se_tpg, bool enable)3772{3773	struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);3774 3775	mutex_lock(&sport->mutex);3776	srpt_set_enabled(sport, enable);3777	mutex_unlock(&sport->mutex);3778 3779	return 0;3780}3781 3782/**3783 * srpt_make_tpg - configfs callback invoked for mkdir /sys/kernel/config/target/$driver/$port/$tpg3784 * @wwn: Corresponds to $driver/$port.3785 * @name: $tpg.3786 */3787static struct se_portal_group *srpt_make_tpg(struct se_wwn *wwn,3788					     const char *name)3789{3790	struct srpt_port_id *sport_id = srpt_wwn_to_sport_id(wwn);3791	struct srpt_tpg *stpg;3792	int res = -ENOMEM;3793 3794	stpg = kzalloc(sizeof(*stpg), GFP_KERNEL);3795	if (!stpg)3796		return ERR_PTR(res);3797	stpg->sport_id = sport_id;3798	res = core_tpg_register(wwn, &stpg->tpg, SCSI_PROTOCOL_SRP);3799	if (res) {3800		kfree(stpg);3801		return ERR_PTR(res);3802	}3803 3804	mutex_lock(&sport_id->mutex);3805	list_add_tail(&stpg->entry, &sport_id->tpg_list);3806	mutex_unlock(&sport_id->mutex);3807 3808	return &stpg->tpg;3809}3810 3811/**3812 * srpt_drop_tpg - configfs callback invoked for rmdir /sys/kernel/config/target/$driver/$port/$tpg3813 * @tpg: Target portal group to deregister.3814 */3815static void srpt_drop_tpg(struct se_portal_group *tpg)3816{3817	struct srpt_tpg *stpg = container_of(tpg, typeof(*stpg), tpg);3818	struct srpt_port_id *sport_id = stpg->sport_id;3819	struct srpt_port *sport = srpt_tpg_to_sport(tpg);3820 3821	mutex_lock(&sport_id->mutex);3822	list_del(&stpg->entry);3823	mutex_unlock(&sport_id->mutex);3824 3825	sport->enabled = false;3826	core_tpg_deregister(tpg);3827	kfree(stpg);3828}3829 3830/**3831 * srpt_make_tport - configfs callback invoked for mkdir /sys/kernel/config/target/$driver/$port3832 * @tf: Not used.3833 * @group: Not used.3834 * @name: $port.3835 */3836static struct se_wwn *srpt_make_tport(struct target_fabric_configfs *tf,3837				      struct config_group *group,3838				      const char *name)3839{3840	struct port_and_port_id papi = srpt_lookup_port(name);3841	struct srpt_port *sport = papi.sport;3842	struct srpt_port_id *port_id;3843 3844	if (!papi.port_id)3845		return ERR_PTR(-EINVAL);3846	if (*papi.port_id) {3847		/* Attempt to create a directory that already exists. */3848		WARN_ON_ONCE(true);3849		return &(*papi.port_id)->wwn;3850	}3851	port_id = kzalloc(sizeof(*port_id), GFP_KERNEL);3852	if (!port_id) {3853		srpt_sdev_put(sport->sdev);3854		return ERR_PTR(-ENOMEM);3855	}3856	mutex_init(&port_id->mutex);3857	INIT_LIST_HEAD(&port_id->tpg_list);3858	port_id->wwn.priv = sport;3859	memcpy(port_id->name, port_id == sport->guid_id ? sport->guid_name :3860	       sport->gid_name, ARRAY_SIZE(port_id->name));3861 3862	*papi.port_id = port_id;3863 3864	return &port_id->wwn;3865}3866 3867/**3868 * srpt_drop_tport - configfs callback invoked for rmdir /sys/kernel/config/target/$driver/$port3869 * @wwn: $port.3870 */3871static void srpt_drop_tport(struct se_wwn *wwn)3872{3873	struct srpt_port_id *port_id = container_of(wwn, typeof(*port_id), wwn);3874	struct srpt_port *sport = wwn->priv;3875 3876	if (sport->guid_id == port_id)3877		sport->guid_id = NULL;3878	else if (sport->gid_id == port_id)3879		sport->gid_id = NULL;3880	else3881		WARN_ON_ONCE(true);3882 3883	srpt_sdev_put(sport->sdev);3884	kfree(port_id);3885}3886 3887static ssize_t srpt_wwn_version_show(struct config_item *item, char *buf)3888{3889	return sysfs_emit(buf, "\n");3890}3891 3892CONFIGFS_ATTR_RO(srpt_wwn_, version);3893 3894static struct configfs_attribute *srpt_wwn_attrs[] = {3895	&srpt_wwn_attr_version,3896	NULL,3897};3898 3899static const struct target_core_fabric_ops srpt_template = {3900	.module				= THIS_MODULE,3901	.fabric_name			= "srpt",3902	.tpg_get_wwn			= srpt_get_fabric_wwn,3903	.tpg_get_tag			= srpt_get_tag,3904	.tpg_check_demo_mode_cache	= srpt_check_true,3905	.tpg_check_demo_mode_write_protect = srpt_check_true,3906	.release_cmd			= srpt_release_cmd,3907	.check_stop_free		= srpt_check_stop_free,3908	.close_session			= srpt_close_session,3909	.sess_get_initiator_sid		= NULL,3910	.write_pending			= srpt_write_pending,3911	.get_cmd_state			= srpt_get_tcm_cmd_state,3912	.queue_data_in			= srpt_queue_data_in,3913	.queue_status			= srpt_queue_status,3914	.queue_tm_rsp			= srpt_queue_tm_rsp,3915	.aborted_task			= srpt_aborted_task,3916	/*3917	 * Setup function pointers for generic logic in3918	 * target_core_fabric_configfs.c3919	 */3920	.fabric_make_wwn		= srpt_make_tport,3921	.fabric_drop_wwn		= srpt_drop_tport,3922	.fabric_make_tpg		= srpt_make_tpg,3923	.fabric_enable_tpg		= srpt_enable_tpg,3924	.fabric_drop_tpg		= srpt_drop_tpg,3925	.fabric_init_nodeacl		= srpt_init_nodeacl,3926 3927	.tfc_discovery_attrs		= srpt_da_attrs,3928	.tfc_wwn_attrs			= srpt_wwn_attrs,3929	.tfc_tpg_attrib_attrs		= srpt_tpg_attrib_attrs,3930 3931	.default_submit_type		= TARGET_DIRECT_SUBMIT,3932	.direct_submit_supp		= 1,3933};3934 3935/**3936 * srpt_init_module - kernel module initialization3937 *3938 * Note: Since ib_register_client() registers callback functions, and since at3939 * least one of these callback functions (srpt_add_one()) calls target core3940 * functions, this driver must be registered with the target core before3941 * ib_register_client() is called.3942 */3943static int __init srpt_init_module(void)3944{3945	int ret;3946 3947	ret = -EINVAL;3948	if (srp_max_req_size < MIN_MAX_REQ_SIZE) {3949		pr_err("invalid value %d for kernel module parameter srp_max_req_size -- must be at least %d.\n",3950		       srp_max_req_size, MIN_MAX_REQ_SIZE);3951		goto out;3952	}3953 3954	if (srpt_srq_size < MIN_SRPT_SRQ_SIZE3955	    || srpt_srq_size > MAX_SRPT_SRQ_SIZE) {3956		pr_err("invalid value %d for kernel module parameter srpt_srq_size -- must be in the range [%d..%d].\n",3957		       srpt_srq_size, MIN_SRPT_SRQ_SIZE, MAX_SRPT_SRQ_SIZE);3958		goto out;3959	}3960 3961	ret = target_register_template(&srpt_template);3962	if (ret)3963		goto out;3964 3965	ret = ib_register_client(&srpt_client);3966	if (ret) {3967		pr_err("couldn't register IB client\n");3968		goto out_unregister_target;3969	}3970 3971	return 0;3972 3973out_unregister_target:3974	target_unregister_template(&srpt_template);3975out:3976	return ret;3977}3978 3979static void __exit srpt_cleanup_module(void)3980{3981	if (rdma_cm_id)3982		rdma_destroy_id(rdma_cm_id);3983	ib_unregister_client(&srpt_client);3984	target_unregister_template(&srpt_template);3985}3986 3987module_init(srpt_init_module);3988module_exit(srpt_cleanup_module);3989