diff options
Diffstat (limited to 'drivers/infiniband/ulp/srpt')
| -rw-r--r-- | drivers/infiniband/ulp/srpt/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/infiniband/ulp/srpt/Makefile | 2 | ||||
| -rw-r--r-- | drivers/infiniband/ulp/srpt/ib_dm_mad.h | 139 | ||||
| -rw-r--r-- | drivers/infiniband/ulp/srpt/ib_srpt.c | 3984 | ||||
| -rw-r--r-- | drivers/infiniband/ulp/srpt/ib_srpt.h | 469 |
5 files changed, 4607 insertions, 0 deletions
diff --git a/drivers/infiniband/ulp/srpt/Kconfig b/drivers/infiniband/ulp/srpt/Kconfig new file mode 100644 index 000000000..4b5d9b792 --- /dev/null +++ b/drivers/infiniband/ulp/srpt/Kconfig @@ -0,0 +1,13 @@ +# SPDX-License-Identifier: GPL-2.0-only +config INFINIBAND_SRPT + tristate "InfiniBand SCSI RDMA Protocol target support" + depends on INFINIBAND && INFINIBAND_ADDR_TRANS && TARGET_CORE + help + + Support for the SCSI RDMA Protocol (SRP) Target driver. The + SRP protocol is a protocol that allows an initiator to access + a block storage device on another host (target) over a network + that supports the RDMA protocol. Currently the RDMA protocol is + supported by InfiniBand and by iWarp network hardware. More + information about the SRP protocol can be found on the website + of the INCITS T10 technical committee (http://www.t10.org/). diff --git a/drivers/infiniband/ulp/srpt/Makefile b/drivers/infiniband/ulp/srpt/Makefile new file mode 100644 index 000000000..2d137928a --- /dev/null +++ b/drivers/infiniband/ulp/srpt/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_INFINIBAND_SRPT) += ib_srpt.o diff --git a/drivers/infiniband/ulp/srpt/ib_dm_mad.h b/drivers/infiniband/ulp/srpt/ib_dm_mad.h new file mode 100644 index 000000000..fb1de1f6f --- /dev/null +++ b/drivers/infiniband/ulp/srpt/ib_dm_mad.h @@ -0,0 +1,139 @@ +/* + * Copyright (c) 2006 - 2009 Mellanox Technology Inc. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ + +#ifndef IB_DM_MAD_H +#define IB_DM_MAD_H + +#include <linux/types.h> + +#include <rdma/ib_mad.h> + +enum { + /* + * See also section 13.4.7 Status Field, table 115 MAD Common Status + * Field Bit Values and also section 16.3.1.1 Status Field in the + * InfiniBand Architecture Specification. + */ + DM_MAD_STATUS_UNSUP_METHOD = 0x0008, + DM_MAD_STATUS_UNSUP_METHOD_ATTR = 0x000c, + DM_MAD_STATUS_INVALID_FIELD = 0x001c, + DM_MAD_STATUS_NO_IOC = 0x0100, + + /* + * See also the Device Management chapter, section 16.3.3 Attributes, + * table 279 Device Management Attributes in the InfiniBand + * Architecture Specification. + */ + DM_ATTR_CLASS_PORT_INFO = 0x01, + DM_ATTR_IOU_INFO = 0x10, + DM_ATTR_IOC_PROFILE = 0x11, + DM_ATTR_SVC_ENTRIES = 0x12 +}; + +struct ib_dm_hdr { + u8 reserved[28]; +}; + +/* + * Structure of management datagram sent by the SRP target implementation. + * Contains a management datagram header, reliable multi-packet transaction + * protocol (RMPP) header and ib_dm_hdr. Notes: + * - The SRP target implementation does not use RMPP or ib_dm_hdr when sending + * management datagrams. + * - The header size must be exactly 64 bytes (IB_MGMT_DEVICE_HDR), since this + * is the header size that is passed to ib_create_send_mad() in ib_srpt.c. + * - The maximum supported size for a management datagram when not using RMPP + * is 256 bytes -- 64 bytes header and 192 (IB_MGMT_DEVICE_DATA) bytes data. + */ +struct ib_dm_mad { + struct ib_mad_hdr mad_hdr; + struct ib_rmpp_hdr rmpp_hdr; + struct ib_dm_hdr dm_hdr; + u8 data[IB_MGMT_DEVICE_DATA]; +}; + +/* + * IOUnitInfo as defined in section 16.3.3.3 IOUnitInfo of the InfiniBand + * Architecture Specification. + */ +struct ib_dm_iou_info { + __be16 change_id; + u8 max_controllers; + u8 op_rom; + u8 controller_list[128]; +}; + +/* + * IOControllerprofile as defined in section 16.3.3.4 IOControllerProfile of + * the InfiniBand Architecture Specification. + */ +struct ib_dm_ioc_profile { + __be64 guid; + __be32 vendor_id; + __be32 device_id; + __be16 device_version; + __be16 reserved1; + __be32 subsys_vendor_id; + __be32 subsys_device_id; + __be16 io_class; + __be16 io_subclass; + __be16 protocol; + __be16 protocol_version; + __be16 service_conn; + __be16 initiators_supported; + __be16 send_queue_depth; + u8 reserved2; + u8 rdma_read_depth; + __be32 send_size; + __be32 rdma_size; + u8 op_cap_mask; + u8 svc_cap_mask; + u8 num_svc_entries; + u8 reserved3[9]; + u8 id_string[64]; +}; + +struct ib_dm_svc_entry { + u8 name[40]; + __be64 id; +}; + +/* + * See also section 16.3.3.5 ServiceEntries in the InfiniBand Architecture + * Specification. See also section B.7, table B.8 in the T10 SRP r16a document. + */ +struct ib_dm_svc_entries { + struct ib_dm_svc_entry service_entries[4]; +}; + +#endif diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c new file mode 100644 index 000000000..983f59c87 --- /dev/null +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c @@ -0,0 +1,3984 @@ +/* + * Copyright (c) 2006 - 2009 Mellanox Technology Inc. All rights reserved. + * Copyright (C) 2008 - 2011 Bart Van Assche <bvanassche@acm.org>. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/ctype.h> +#include <linux/kthread.h> +#include <linux/string.h> +#include <linux/delay.h> +#include <linux/atomic.h> +#include <linux/inet.h> +#include <rdma/ib_cache.h> +#include <scsi/scsi_proto.h> +#include <scsi/scsi_tcq.h> +#include <target/target_core_base.h> +#include <target/target_core_fabric.h> +#include "ib_srpt.h" + +/* Name of this kernel module. */ +#define DRV_NAME "ib_srpt" + +#define SRPT_ID_STRING "Linux SRP target" + +#undef pr_fmt +#define pr_fmt(fmt) DRV_NAME " " fmt + +MODULE_AUTHOR("Vu Pham and Bart Van Assche"); +MODULE_DESCRIPTION("SCSI RDMA Protocol target driver"); +MODULE_LICENSE("Dual BSD/GPL"); + +/* + * Global Variables + */ + +static u64 srpt_service_guid; +static DEFINE_SPINLOCK(srpt_dev_lock); /* Protects srpt_dev_list. */ +static LIST_HEAD(srpt_dev_list); /* List of srpt_device structures. */ + +static unsigned srp_max_req_size = DEFAULT_MAX_REQ_SIZE; +module_param(srp_max_req_size, int, 0444); +MODULE_PARM_DESC(srp_max_req_size, + "Maximum size of SRP request messages in bytes."); + +static int srpt_srq_size = DEFAULT_SRPT_SRQ_SIZE; +module_param(srpt_srq_size, int, 0444); +MODULE_PARM_DESC(srpt_srq_size, + "Shared receive queue (SRQ) size."); + +static int srpt_get_u64_x(char *buffer, const struct kernel_param *kp) +{ + return sprintf(buffer, "0x%016llx\n", *(u64 *)kp->arg); +} +module_param_call(srpt_service_guid, NULL, srpt_get_u64_x, &srpt_service_guid, + 0444); +MODULE_PARM_DESC(srpt_service_guid, + "Using this value for ioc_guid, id_ext, and cm_listen_id instead of using the node_guid of the first HCA."); + +static struct ib_client srpt_client; +/* Protects both rdma_cm_port and rdma_cm_id. */ +static DEFINE_MUTEX(rdma_cm_mutex); +/* Port number RDMA/CM will bind to. */ +static u16 rdma_cm_port; +static struct rdma_cm_id *rdma_cm_id; +static void srpt_release_cmd(struct se_cmd *se_cmd); +static void srpt_free_ch(struct kref *kref); +static int srpt_queue_status(struct se_cmd *cmd); +static void srpt_recv_done(struct ib_cq *cq, struct ib_wc *wc); +static void srpt_send_done(struct ib_cq *cq, struct ib_wc *wc); +static void srpt_process_wait_list(struct srpt_rdma_ch *ch); + +/* + * The only allowed channel state changes are those that change the channel + * state into a state with a higher numerical value. Hence the new > prev test. + */ +static bool srpt_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state new) +{ + unsigned long flags; + enum rdma_ch_state prev; + bool changed = false; + + spin_lock_irqsave(&ch->spinlock, flags); + prev = ch->state; + if (new > prev) { + ch->state = new; + changed = true; + } + spin_unlock_irqrestore(&ch->spinlock, flags); + + return changed; +} + +/** + * srpt_event_handler - asynchronous IB event callback function + * @handler: IB event handler registered by ib_register_event_handler(). + * @event: Description of the event that occurred. + * + * Callback function called by the InfiniBand core when an asynchronous IB + * event occurs. This callback may occur in interrupt context. See also + * section 11.5.2, Set Asynchronous Event Handler in the InfiniBand + * Architecture Specification. + */ +static void srpt_event_handler(struct ib_event_handler *handler, + struct ib_event *event) +{ + struct srpt_device *sdev = + container_of(handler, struct srpt_device, event_handler); + struct srpt_port *sport; + u8 port_num; + + pr_debug("ASYNC event= %d on device= %s\n", event->event, + dev_name(&sdev->device->dev)); + + switch (event->event) { + case IB_EVENT_PORT_ERR: + port_num = event->element.port_num - 1; + if (port_num < sdev->device->phys_port_cnt) { + sport = &sdev->port[port_num]; + sport->lid = 0; + sport->sm_lid = 0; + } else { + WARN(true, "event %d: port_num %d out of range 1..%d\n", + event->event, port_num + 1, + sdev->device->phys_port_cnt); + } + break; + case IB_EVENT_PORT_ACTIVE: + case IB_EVENT_LID_CHANGE: + case IB_EVENT_PKEY_CHANGE: + case IB_EVENT_SM_CHANGE: + case IB_EVENT_CLIENT_REREGISTER: + case IB_EVENT_GID_CHANGE: + /* Refresh port data asynchronously. */ + port_num = event->element.port_num - 1; + if (port_num < sdev->device->phys_port_cnt) { + sport = &sdev->port[port_num]; + if (!sport->lid && !sport->sm_lid) + schedule_work(&sport->work); + } else { + WARN(true, "event %d: port_num %d out of range 1..%d\n", + event->event, port_num + 1, + sdev->device->phys_port_cnt); + } + break; + default: + pr_err("received unrecognized IB event %d\n", event->event); + break; + } +} + +/** + * srpt_srq_event - SRQ event callback function + * @event: Description of the event that occurred. + * @ctx: Context pointer specified at SRQ creation time. + */ +static void srpt_srq_event(struct ib_event *event, void *ctx) +{ + pr_debug("SRQ event %d\n", event->event); +} + +static const char *get_ch_state_name(enum rdma_ch_state s) +{ + switch (s) { + case CH_CONNECTING: + return "connecting"; + case CH_LIVE: + return "live"; + case CH_DISCONNECTING: + return "disconnecting"; + case CH_DRAINING: + return "draining"; + case CH_DISCONNECTED: + return "disconnected"; + } + return "???"; +} + +/** + * srpt_qp_event - QP event callback function + * @event: Description of the event that occurred. + * @ch: SRPT RDMA channel. + */ +static void srpt_qp_event(struct ib_event *event, struct srpt_rdma_ch *ch) +{ + pr_debug("QP event %d on ch=%p sess_name=%s-%d state=%s\n", + event->event, ch, ch->sess_name, ch->qp->qp_num, + get_ch_state_name(ch->state)); + + switch (event->event) { + case IB_EVENT_COMM_EST: + if (ch->using_rdma_cm) + rdma_notify(ch->rdma_cm.cm_id, event->event); + else + ib_cm_notify(ch->ib_cm.cm_id, event->event); + break; + case IB_EVENT_QP_LAST_WQE_REACHED: + pr_debug("%s-%d, state %s: received Last WQE event.\n", + ch->sess_name, ch->qp->qp_num, + get_ch_state_name(ch->state)); + break; + default: + pr_err("received unrecognized IB QP event %d\n", event->event); + break; + } +} + +/** + * srpt_set_ioc - initialize a IOUnitInfo structure + * @c_list: controller list. + * @slot: one-based slot number. + * @value: four-bit value. + * + * Copies the lowest four bits of value in element slot of the array of four + * bit elements called c_list (controller list). The index slot is one-based. + */ +static void srpt_set_ioc(u8 *c_list, u32 slot, u8 value) +{ + u16 id; + u8 tmp; + + id = (slot - 1) / 2; + if (slot & 0x1) { + tmp = c_list[id] & 0xf; + c_list[id] = (value << 4) | tmp; + } else { + tmp = c_list[id] & 0xf0; + c_list[id] = (value & 0xf) | tmp; + } +} + +/** + * srpt_get_class_port_info - copy ClassPortInfo to a management datagram + * @mad: Datagram that will be sent as response to DM_ATTR_CLASS_PORT_INFO. + * + * See also section 16.3.3.1 ClassPortInfo in the InfiniBand Architecture + * Specification. + */ +static void srpt_get_class_port_info(struct ib_dm_mad *mad) +{ + struct ib_class_port_info *cif; + + cif = (struct ib_class_port_info *)mad->data; + memset(cif, 0, sizeof(*cif)); + cif->base_version = 1; + cif->class_version = 1; + + ib_set_cpi_resp_time(cif, 20); + mad->mad_hdr.status = 0; +} + +/** + * srpt_get_iou - write IOUnitInfo to a management datagram + * @mad: Datagram that will be sent as response to DM_ATTR_IOU_INFO. + * + * See also section 16.3.3.3 IOUnitInfo in the InfiniBand Architecture + * Specification. See also section B.7, table B.6 in the SRP r16a document. + */ +static void srpt_get_iou(struct ib_dm_mad *mad) +{ + struct ib_dm_iou_info *ioui; + u8 slot; + int i; + + ioui = (struct ib_dm_iou_info *)mad->data; + ioui->change_id = cpu_to_be16(1); + ioui->max_controllers = 16; + + /* set present for slot 1 and empty for the rest */ + srpt_set_ioc(ioui->controller_list, 1, 1); + for (i = 1, slot = 2; i < 16; i++, slot++) + srpt_set_ioc(ioui->controller_list, slot, 0); + + mad->mad_hdr.status = 0; +} + +/** + * srpt_get_ioc - write IOControllerprofile to a management datagram + * @sport: HCA port through which the MAD has been received. + * @slot: Slot number specified in DM_ATTR_IOC_PROFILE query. + * @mad: Datagram that will be sent as response to DM_ATTR_IOC_PROFILE. + * + * See also section 16.3.3.4 IOControllerProfile in the InfiniBand + * Architecture Specification. See also section B.7, table B.7 in the SRP + * r16a document. + */ +static void srpt_get_ioc(struct srpt_port *sport, u32 slot, + struct ib_dm_mad *mad) +{ + struct srpt_device *sdev = sport->sdev; + struct ib_dm_ioc_profile *iocp; + int send_queue_depth; + + iocp = (struct ib_dm_ioc_profile *)mad->data; + + if (!slot || slot > 16) { + mad->mad_hdr.status + = cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD); + return; + } + + if (slot > 2) { + mad->mad_hdr.status + = cpu_to_be16(DM_MAD_STATUS_NO_IOC); + return; + } + + if (sdev->use_srq) + send_queue_depth = sdev->srq_size; + else + send_queue_depth = min(MAX_SRPT_RQ_SIZE, + sdev->device->attrs.max_qp_wr); + + memset(iocp, 0, sizeof(*iocp)); + strcpy(iocp->id_string, SRPT_ID_STRING); + iocp->guid = cpu_to_be64(srpt_service_guid); + iocp->vendor_id = cpu_to_be32(sdev->device->attrs.vendor_id); + iocp->device_id = cpu_to_be32(sdev->device->attrs.vendor_part_id); + iocp->device_version = cpu_to_be16(sdev->device->attrs.hw_ver); + iocp->subsys_vendor_id = cpu_to_be32(sdev->device->attrs.vendor_id); + iocp->subsys_device_id = 0x0; + iocp->io_class = cpu_to_be16(SRP_REV16A_IB_IO_CLASS); + iocp->io_subclass = cpu_to_be16(SRP_IO_SUBCLASS); + iocp->protocol = cpu_to_be16(SRP_PROTOCOL); + iocp->protocol_version = cpu_to_be16(SRP_PROTOCOL_VERSION); + iocp->send_queue_depth = cpu_to_be16(send_queue_depth); + iocp->rdma_read_depth = 4; + iocp->send_size = cpu_to_be32(srp_max_req_size); + iocp->rdma_size = cpu_to_be32(min(sport->port_attrib.srp_max_rdma_size, + 1U << 24)); + iocp->num_svc_entries = 1; + iocp->op_cap_mask = SRP_SEND_TO_IOC | SRP_SEND_FROM_IOC | + SRP_RDMA_READ_FROM_IOC | SRP_RDMA_WRITE_FROM_IOC; + + mad->mad_hdr.status = 0; +} + +/** + * srpt_get_svc_entries - write ServiceEntries to a management datagram + * @ioc_guid: I/O controller GUID to use in reply. + * @slot: I/O controller number. + * @hi: End of the range of service entries to be specified in the reply. + * @lo: Start of the range of service entries to be specified in the reply.. + * @mad: Datagram that will be sent as response to DM_ATTR_SVC_ENTRIES. + * + * See also section 16.3.3.5 ServiceEntries in the InfiniBand Architecture + * Specification. See also section B.7, table B.8 in the SRP r16a document. + */ +static void srpt_get_svc_entries(u64 ioc_guid, + u16 slot, u8 hi, u8 lo, struct ib_dm_mad *mad) +{ + struct ib_dm_svc_entries *svc_entries; + + WARN_ON(!ioc_guid); + + if (!slot || slot > 16) { + mad->mad_hdr.status + = cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD); + return; + } + + if (slot > 2 || lo > hi || hi > 1) { + mad->mad_hdr.status + = cpu_to_be16(DM_MAD_STATUS_NO_IOC); + return; + } + + svc_entries = (struct ib_dm_svc_entries *)mad->data; + memset(svc_entries, 0, sizeof(*svc_entries)); + svc_entries->service_entries[0].id = cpu_to_be64(ioc_guid); + snprintf(svc_entries->service_entries[0].name, + sizeof(svc_entries->service_entries[0].name), + "%s%016llx", + SRP_SERVICE_NAME_PREFIX, + ioc_guid); + + mad->mad_hdr.status = 0; +} + +/** + * srpt_mgmt_method_get - process a received management datagram + * @sp: HCA port through which the MAD has been received. + * @rq_mad: received MAD. + * @rsp_mad: response MAD. + */ +static void srpt_mgmt_method_get(struct srpt_port *sp, struct ib_mad *rq_mad, + struct ib_dm_mad *rsp_mad) +{ + u16 attr_id; + u32 slot; + u8 hi, lo; + + attr_id = be16_to_cpu(rq_mad->mad_hdr.attr_id); + switch (attr_id) { + case DM_ATTR_CLASS_PORT_INFO: + srpt_get_class_port_info(rsp_mad); + break; + case DM_ATTR_IOU_INFO: + srpt_get_iou(rsp_mad); + break; + case DM_ATTR_IOC_PROFILE: + slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod); + srpt_get_ioc(sp, slot, rsp_mad); + break; + case DM_ATTR_SVC_ENTRIES: + slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod); + hi = (u8) ((slot >> 8) & 0xff); + lo = (u8) (slot & 0xff); + slot = (u16) ((slot >> 16) & 0xffff); + srpt_get_svc_entries(srpt_service_guid, + slot, hi, lo, rsp_mad); + break; + default: + rsp_mad->mad_hdr.status = + cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR); + break; + } +} + +/** + * srpt_mad_send_handler - MAD send completion callback + * @mad_agent: Return value of ib_register_mad_agent(). + * @mad_wc: Work completion reporting that the MAD has been sent. + */ +static void srpt_mad_send_handler(struct ib_mad_agent *mad_agent, + struct ib_mad_send_wc *mad_wc) +{ + rdma_destroy_ah(mad_wc->send_buf->ah, RDMA_DESTROY_AH_SLEEPABLE); + ib_free_send_mad(mad_wc->send_buf); +} + +/** + * srpt_mad_recv_handler - MAD reception callback function + * @mad_agent: Return value of ib_register_mad_agent(). + * @send_buf: Not used. + * @mad_wc: Work completion reporting that a MAD has been received. + */ +static void srpt_mad_recv_handler(struct ib_mad_agent *mad_agent, + struct ib_mad_send_buf *send_buf, + struct ib_mad_recv_wc *mad_wc) +{ + struct srpt_port *sport = (struct srpt_port *)mad_agent->context; + struct ib_ah *ah; + struct ib_mad_send_buf *rsp; + struct ib_dm_mad *dm_mad; + + if (!mad_wc || !mad_wc->recv_buf.mad) + return; + + ah = ib_create_ah_from_wc(mad_agent->qp->pd, mad_wc->wc, + mad_wc->recv_buf.grh, mad_agent->port_num); + if (IS_ERR(ah)) + goto err; + + BUILD_BUG_ON(offsetof(struct ib_dm_mad, data) != IB_MGMT_DEVICE_HDR); + + rsp = ib_create_send_mad(mad_agent, mad_wc->wc->src_qp, + mad_wc->wc->pkey_index, 0, + IB_MGMT_DEVICE_HDR, IB_MGMT_DEVICE_DATA, + GFP_KERNEL, + IB_MGMT_BASE_VERSION); + if (IS_ERR(rsp)) + goto err_rsp; + + rsp->ah = ah; + + dm_mad = rsp->mad; + memcpy(dm_mad, mad_wc->recv_buf.mad, sizeof(*dm_mad)); + dm_mad->mad_hdr.method = IB_MGMT_METHOD_GET_RESP; + dm_mad->mad_hdr.status = 0; + + switch (mad_wc->recv_buf.mad->mad_hdr.method) { + case IB_MGMT_METHOD_GET: + srpt_mgmt_method_get(sport, mad_wc->recv_buf.mad, dm_mad); + break; + case IB_MGMT_METHOD_SET: + dm_mad->mad_hdr.status = + cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR); + break; + default: + dm_mad->mad_hdr.status = + cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD); + break; + } + + if (!ib_post_send_mad(rsp, NULL)) { + ib_free_recv_mad(mad_wc); + /* will destroy_ah & free_send_mad in send completion */ + return; + } + + ib_free_send_mad(rsp); + +err_rsp: + rdma_destroy_ah(ah, RDMA_DESTROY_AH_SLEEPABLE); +err: + ib_free_recv_mad(mad_wc); +} + +static int srpt_format_guid(char *buf, unsigned int size, const __be64 *guid) +{ + const __be16 *g = (const __be16 *)guid; + + return snprintf(buf, size, "%04x:%04x:%04x:%04x", + be16_to_cpu(g[0]), be16_to_cpu(g[1]), + be16_to_cpu(g[2]), be16_to_cpu(g[3])); +} + +/** + * srpt_refresh_port - configure a HCA port + * @sport: SRPT HCA port. + * + * Enable InfiniBand management datagram processing, update the cached sm_lid, + * lid and gid values, and register a callback function for processing MADs + * on the specified port. + * + * Note: It is safe to call this function more than once for the same port. + */ +static int srpt_refresh_port(struct srpt_port *sport) +{ + struct ib_mad_agent *mad_agent; + struct ib_mad_reg_req reg_req; + struct ib_port_modify port_modify; + struct ib_port_attr port_attr; + int ret; + + ret = ib_query_port(sport->sdev->device, sport->port, &port_attr); + if (ret) + return ret; + + sport->sm_lid = port_attr.sm_lid; + sport->lid = port_attr.lid; + + ret = rdma_query_gid(sport->sdev->device, sport->port, 0, &sport->gid); + if (ret) + return ret; + + srpt_format_guid(sport->guid_name, ARRAY_SIZE(sport->guid_name), + &sport->gid.global.interface_id); + snprintf(sport->gid_name, ARRAY_SIZE(sport->gid_name), + "0x%016llx%016llx", + be64_to_cpu(sport->gid.global.subnet_prefix), + be64_to_cpu(sport->gid.global.interface_id)); + + if (rdma_protocol_iwarp(sport->sdev->device, sport->port)) + return 0; + + memset(&port_modify, 0, sizeof(port_modify)); + port_modify.set_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP; + port_modify.clr_port_cap_mask = 0; + + ret = ib_modify_port(sport->sdev->device, sport->port, 0, &port_modify); + if (ret) { + pr_warn("%s-%d: enabling device management failed (%d). Note: this is expected if SR-IOV is enabled.\n", + dev_name(&sport->sdev->device->dev), sport->port, ret); + return 0; + } + + if (!sport->mad_agent) { + memset(®_req, 0, sizeof(reg_req)); + reg_req.mgmt_class = IB_MGMT_CLASS_DEVICE_MGMT; + reg_req.mgmt_class_version = IB_MGMT_BASE_VERSION; + set_bit(IB_MGMT_METHOD_GET, reg_req.method_mask); + set_bit(IB_MGMT_METHOD_SET, reg_req.method_mask); + + mad_agent = ib_register_mad_agent(sport->sdev->device, + sport->port, + IB_QPT_GSI, + ®_req, 0, + srpt_mad_send_handler, + srpt_mad_recv_handler, + sport, 0); + if (IS_ERR(mad_agent)) { + pr_err("%s-%d: MAD agent registration failed (%ld). Note: this is expected if SR-IOV is enabled.\n", + dev_name(&sport->sdev->device->dev), sport->port, + PTR_ERR(mad_agent)); + sport->mad_agent = NULL; + memset(&port_modify, 0, sizeof(port_modify)); + port_modify.clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP; + ib_modify_port(sport->sdev->device, sport->port, 0, + &port_modify); + return 0; + } + + sport->mad_agent = mad_agent; + } + + return 0; +} + +/** + * srpt_unregister_mad_agent - unregister MAD callback functions + * @sdev: SRPT HCA pointer. + * @port_cnt: number of ports with registered MAD + * + * Note: It is safe to call this function more than once for the same device. + */ +static void srpt_unregister_mad_agent(struct srpt_device *sdev, int port_cnt) +{ + struct ib_port_modify port_modify = { + .clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP, + }; + struct srpt_port *sport; + int i; + + for (i = 1; i <= port_cnt; i++) { + sport = &sdev->port[i - 1]; + WARN_ON(sport->port != i); + if (sport->mad_agent) { + ib_modify_port(sdev->device, i, 0, &port_modify); + ib_unregister_mad_agent(sport->mad_agent); + sport->mad_agent = NULL; + } + } +} + +/** + * srpt_alloc_ioctx - allocate a SRPT I/O context structure + * @sdev: SRPT HCA pointer. + * @ioctx_size: I/O context size. + * @buf_cache: I/O buffer cache. + * @dir: DMA data direction. + */ +static struct srpt_ioctx *srpt_alloc_ioctx(struct srpt_device *sdev, + int ioctx_size, + struct kmem_cache *buf_cache, + enum dma_data_direction dir) +{ + struct srpt_ioctx *ioctx; + + ioctx = kzalloc(ioctx_size, GFP_KERNEL); + if (!ioctx) + goto err; + + ioctx->buf = kmem_cache_alloc(buf_cache, GFP_KERNEL); + if (!ioctx->buf) + goto err_free_ioctx; + + ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf, + kmem_cache_size(buf_cache), dir); + if (ib_dma_mapping_error(sdev->device, ioctx->dma)) + goto err_free_buf; + + return ioctx; + +err_free_buf: + kmem_cache_free(buf_cache, ioctx->buf); +err_free_ioctx: + kfree(ioctx); +err: + return NULL; +} + +/** + * srpt_free_ioctx - free a SRPT I/O context structure + * @sdev: SRPT HCA pointer. + * @ioctx: I/O context pointer. + * @buf_cache: I/O buffer cache. + * @dir: DMA data direction. + */ +static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx, + struct kmem_cache *buf_cache, + enum dma_data_direction dir) +{ + if (!ioctx) + return; + + ib_dma_unmap_single(sdev->device, ioctx->dma, + kmem_cache_size(buf_cache), dir); + kmem_cache_free(buf_cache, ioctx->buf); + kfree(ioctx); +} + +/** + * srpt_alloc_ioctx_ring - allocate a ring of SRPT I/O context structures + * @sdev: Device to allocate the I/O context ring for. + * @ring_size: Number of elements in the I/O context ring. + * @ioctx_size: I/O context size. + * @buf_cache: I/O buffer cache. + * @alignment_offset: Offset in each ring buffer at which the SRP information + * unit starts. + * @dir: DMA data direction. + */ +static struct srpt_ioctx **srpt_alloc_ioctx_ring(struct srpt_device *sdev, + int ring_size, int ioctx_size, + struct kmem_cache *buf_cache, + int alignment_offset, + enum dma_data_direction dir) +{ + struct srpt_ioctx **ring; + int i; + + WARN_ON(ioctx_size != sizeof(struct srpt_recv_ioctx) && + ioctx_size != sizeof(struct srpt_send_ioctx)); + + ring = kvmalloc_array(ring_size, sizeof(ring[0]), GFP_KERNEL); + if (!ring) + goto out; + for (i = 0; i < ring_size; ++i) { + ring[i] = srpt_alloc_ioctx(sdev, ioctx_size, buf_cache, dir); + if (!ring[i]) + goto err; + ring[i]->index = i; + ring[i]->offset = alignment_offset; + } + goto out; + +err: + while (--i >= 0) + srpt_free_ioctx(sdev, ring[i], buf_cache, dir); + kvfree(ring); + ring = NULL; +out: + return ring; +} + +/** + * srpt_free_ioctx_ring - free the ring of SRPT I/O context structures + * @ioctx_ring: I/O context ring to be freed. + * @sdev: SRPT HCA pointer. + * @ring_size: Number of ring elements. + * @buf_cache: I/O buffer cache. + * @dir: DMA data direction. + */ +static void srpt_free_ioctx_ring(struct srpt_ioctx **ioctx_ring, + struct srpt_device *sdev, int ring_size, + struct kmem_cache *buf_cache, + enum dma_data_direction dir) +{ + int i; + + if (!ioctx_ring) + return; + + for (i = 0; i < ring_size; ++i) + srpt_free_ioctx(sdev, ioctx_ring[i], buf_cache, dir); + kvfree(ioctx_ring); +} + +/** + * srpt_set_cmd_state - set the state of a SCSI command + * @ioctx: Send I/O context. + * @new: New I/O context state. + * + * Does not modify the state of aborted commands. Returns the previous command + * state. + */ +static enum srpt_command_state srpt_set_cmd_state(struct srpt_send_ioctx *ioctx, + enum srpt_command_state new) +{ + enum srpt_command_state previous; + + previous = ioctx->state; + if (previous != SRPT_STATE_DONE) + ioctx->state = new; + + return previous; +} + +/** + * srpt_test_and_set_cmd_state - test and set the state of a command + * @ioctx: Send I/O context. + * @old: Current I/O context state. + * @new: New I/O context state. + * + * Returns true if and only if the previous command state was equal to 'old'. + */ +static bool srpt_test_and_set_cmd_state(struct srpt_send_ioctx *ioctx, + enum srpt_command_state old, + enum srpt_command_state new) +{ + enum srpt_command_state previous; + + WARN_ON(!ioctx); + WARN_ON(old == SRPT_STATE_DONE); + WARN_ON(new == SRPT_STATE_NEW); + + previous = ioctx->state; + if (previous == old) + ioctx->state = new; + + return previous == old; +} + +/** + * srpt_post_recv - post an IB receive request + * @sdev: SRPT HCA pointer. + * @ch: SRPT RDMA channel. + * @ioctx: Receive I/O context pointer. + */ +static int srpt_post_recv(struct srpt_device *sdev, struct srpt_rdma_ch *ch, + struct srpt_recv_ioctx *ioctx) +{ + struct ib_sge list; + struct ib_recv_wr wr; + + BUG_ON(!sdev); + list.addr = ioctx->ioctx.dma + ioctx->ioctx.offset; + list.length = srp_max_req_size; + list.lkey = sdev->lkey; + + ioctx->ioctx.cqe.done = srpt_recv_done; + wr.wr_cqe = &ioctx->ioctx.cqe; + wr.next = NULL; + wr.sg_list = &list; + wr.num_sge = 1; + + if (sdev->use_srq) + return ib_post_srq_recv(sdev->srq, &wr, NULL); + else + return ib_post_recv(ch->qp, &wr, NULL); +} + +/** + * srpt_zerolength_write - perform a zero-length RDMA write + * @ch: SRPT RDMA channel. + * + * A quote from the InfiniBand specification: C9-88: For an HCA responder + * using Reliable Connection service, for each zero-length RDMA READ or WRITE + * request, the R_Key shall not be validated, even if the request includes + * Immediate data. + */ +static int srpt_zerolength_write(struct srpt_rdma_ch *ch) +{ + struct ib_rdma_wr wr = { + .wr = { + .next = NULL, + { .wr_cqe = &ch->zw_cqe, }, + .opcode = IB_WR_RDMA_WRITE, + .send_flags = IB_SEND_SIGNALED, + } + }; + + pr_debug("%s-%d: queued zerolength write\n", ch->sess_name, + ch->qp->qp_num); + + return ib_post_send(ch->qp, &wr.wr, NULL); +} + +static void srpt_zerolength_write_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct srpt_rdma_ch *ch = wc->qp->qp_context; + + pr_debug("%s-%d wc->status %d\n", ch->sess_name, ch->qp->qp_num, + wc->status); + + if (wc->status == IB_WC_SUCCESS) { + srpt_process_wait_list(ch); + } else { + if (srpt_set_ch_state(ch, CH_DISCONNECTED)) + schedule_work(&ch->release_work); + else + pr_debug("%s-%d: already disconnected.\n", + ch->sess_name, ch->qp->qp_num); + } +} + +static int srpt_alloc_rw_ctxs(struct srpt_send_ioctx *ioctx, + struct srp_direct_buf *db, int nbufs, struct scatterlist **sg, + unsigned *sg_cnt) +{ + enum dma_data_direction dir = target_reverse_dma_direction(&ioctx->cmd); + struct srpt_rdma_ch *ch = ioctx->ch; + struct scatterlist *prev = NULL; + unsigned prev_nents; + int ret, i; + + if (nbufs == 1) { + ioctx->rw_ctxs = &ioctx->s_rw_ctx; + } else { + ioctx->rw_ctxs = kmalloc_array(nbufs, sizeof(*ioctx->rw_ctxs), + GFP_KERNEL); + if (!ioctx->rw_ctxs) + return -ENOMEM; + } + + for (i = ioctx->n_rw_ctx; i < nbufs; i++, db++) { + struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i]; + u64 remote_addr = be64_to_cpu(db->va); + u32 size = be32_to_cpu(db->len); + u32 rkey = be32_to_cpu(db->key); + + ret = target_alloc_sgl(&ctx->sg, &ctx->nents, size, false, + i < nbufs - 1); + if (ret) + goto unwind; + + ret = rdma_rw_ctx_init(&ctx->rw, ch->qp, ch->sport->port, + ctx->sg, ctx->nents, 0, remote_addr, rkey, dir); + if (ret < 0) { + target_free_sgl(ctx->sg, ctx->nents); + goto unwind; + } + + ioctx->n_rdma += ret; + ioctx->n_rw_ctx++; + + if (prev) { + sg_unmark_end(&prev[prev_nents - 1]); + sg_chain(prev, prev_nents + 1, ctx->sg); + } else { + *sg = ctx->sg; + } + + prev = ctx->sg; + prev_nents = ctx->nents; + + *sg_cnt += ctx->nents; + } + + return 0; + +unwind: + while (--i >= 0) { + struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i]; + + rdma_rw_ctx_destroy(&ctx->rw, ch->qp, ch->sport->port, + ctx->sg, ctx->nents, dir); + target_free_sgl(ctx->sg, ctx->nents); + } + if (ioctx->rw_ctxs != &ioctx->s_rw_ctx) + kfree(ioctx->rw_ctxs); + return ret; +} + +static void srpt_free_rw_ctxs(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx) +{ + enum dma_data_direction dir = target_reverse_dma_direction(&ioctx->cmd); + int i; + + for (i = 0; i < ioctx->n_rw_ctx; i++) { + struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i]; + + rdma_rw_ctx_destroy(&ctx->rw, ch->qp, ch->sport->port, + ctx->sg, ctx->nents, dir); + target_free_sgl(ctx->sg, ctx->nents); + } + + if (ioctx->rw_ctxs != &ioctx->s_rw_ctx) + kfree(ioctx->rw_ctxs); +} + +static inline void *srpt_get_desc_buf(struct srp_cmd *srp_cmd) +{ + /* + * The pointer computations below will only be compiled correctly + * if srp_cmd::add_data is declared as s8*, u8*, s8[] or u8[], so check + * whether srp_cmd::add_data has been declared as a byte pointer. + */ + BUILD_BUG_ON(!__same_type(srp_cmd->add_data[0], (s8)0) && + !__same_type(srp_cmd->add_data[0], (u8)0)); + + /* + * According to the SRP spec, the lower two bits of the 'ADDITIONAL + * CDB LENGTH' field are reserved and the size in bytes of this field + * is four times the value specified in bits 3..7. Hence the "& ~3". + */ + return srp_cmd->add_data + (srp_cmd->add_cdb_len & ~3); +} + +/** + * srpt_get_desc_tbl - parse the data descriptors of a SRP_CMD request + * @recv_ioctx: I/O context associated with the received command @srp_cmd. + * @ioctx: I/O context that will be used for responding to the initiator. + * @srp_cmd: Pointer to the SRP_CMD request data. + * @dir: Pointer to the variable to which the transfer direction will be + * written. + * @sg: [out] scatterlist for the parsed SRP_CMD. + * @sg_cnt: [out] length of @sg. + * @data_len: Pointer to the variable to which the total data length of all + * descriptors in the SRP_CMD request will be written. + * @imm_data_offset: [in] Offset in SRP_CMD requests at which immediate data + * starts. + * + * This function initializes ioctx->nrbuf and ioctx->r_bufs. + * + * Returns -EINVAL when the SRP_CMD request contains inconsistent descriptors; + * -ENOMEM when memory allocation fails and zero upon success. + */ +static int srpt_get_desc_tbl(struct srpt_recv_ioctx *recv_ioctx, + struct srpt_send_ioctx *ioctx, + struct srp_cmd *srp_cmd, enum dma_data_direction *dir, + struct scatterlist **sg, unsigned int *sg_cnt, u64 *data_len, + u16 imm_data_offset) +{ + BUG_ON(!dir); + BUG_ON(!data_len); + + /* + * The lower four bits of the buffer format field contain the DATA-IN + * buffer descriptor format, and the highest four bits contain the + * DATA-OUT buffer descriptor format. + */ + if (srp_cmd->buf_fmt & 0xf) + /* DATA-IN: transfer data from target to initiator (read). */ + *dir = DMA_FROM_DEVICE; + else if (srp_cmd->buf_fmt >> 4) + /* DATA-OUT: transfer data from initiator to target (write). */ + *dir = DMA_TO_DEVICE; + else + *dir = DMA_NONE; + + /* initialize data_direction early as srpt_alloc_rw_ctxs needs it */ + ioctx->cmd.data_direction = *dir; + + if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_DIRECT) || + ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_DIRECT)) { + struct srp_direct_buf *db = srpt_get_desc_buf(srp_cmd); + + *data_len = be32_to_cpu(db->len); + return srpt_alloc_rw_ctxs(ioctx, db, 1, sg, sg_cnt); + } else if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_INDIRECT) || + ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_INDIRECT)) { + struct srp_indirect_buf *idb = srpt_get_desc_buf(srp_cmd); + int nbufs = be32_to_cpu(idb->table_desc.len) / + sizeof(struct srp_direct_buf); + + if (nbufs > + (srp_cmd->data_out_desc_cnt + srp_cmd->data_in_desc_cnt)) { + pr_err("received unsupported SRP_CMD request type (%u out + %u in != %u / %zu)\n", + srp_cmd->data_out_desc_cnt, + srp_cmd->data_in_desc_cnt, + be32_to_cpu(idb->table_desc.len), + sizeof(struct srp_direct_buf)); + return -EINVAL; + } + + *data_len = be32_to_cpu(idb->len); + return srpt_alloc_rw_ctxs(ioctx, idb->desc_list, nbufs, + sg, sg_cnt); + } else if ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_IMM) { + struct srp_imm_buf *imm_buf = srpt_get_desc_buf(srp_cmd); + void *data = (void *)srp_cmd + imm_data_offset; + uint32_t len = be32_to_cpu(imm_buf->len); + uint32_t req_size = imm_data_offset + len; + + if (req_size > srp_max_req_size) { + pr_err("Immediate data (length %d + %d) exceeds request size %d\n", + imm_data_offset, len, srp_max_req_size); + return -EINVAL; + } + if (recv_ioctx->byte_len < req_size) { + pr_err("Received too few data - %d < %d\n", + recv_ioctx->byte_len, req_size); + return -EIO; + } + /* + * The immediate data buffer descriptor must occur before the + * immediate data itself. + */ + if ((void *)(imm_buf + 1) > (void *)data) { + pr_err("Received invalid write request\n"); + return -EINVAL; + } + *data_len = len; + ioctx->recv_ioctx = recv_ioctx; + if ((uintptr_t)data & 511) { + pr_warn_once("Internal error - the receive buffers are not aligned properly.\n"); + return -EINVAL; + } + sg_init_one(&ioctx->imm_sg, data, len); + *sg = &ioctx->imm_sg; + *sg_cnt = 1; + return 0; + } else { + *data_len = 0; + return 0; + } +} + +/** + * srpt_init_ch_qp - initialize queue pair attributes + * @ch: SRPT RDMA channel. + * @qp: Queue pair pointer. + * + * Initialized the attributes of queue pair 'qp' by allowing local write, + * remote read and remote write. Also transitions 'qp' to state IB_QPS_INIT. + */ +static int srpt_init_ch_qp(struct srpt_rdma_ch *ch, struct ib_qp *qp) +{ + struct ib_qp_attr *attr; + int ret; + + WARN_ON_ONCE(ch->using_rdma_cm); + + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) + return -ENOMEM; + + attr->qp_state = IB_QPS_INIT; + attr->qp_access_flags = IB_ACCESS_LOCAL_WRITE; + attr->port_num = ch->sport->port; + + ret = ib_find_cached_pkey(ch->sport->sdev->device, ch->sport->port, + ch->pkey, &attr->pkey_index); + if (ret < 0) + pr_err("Translating pkey %#x failed (%d) - using index 0\n", + ch->pkey, ret); + + ret = ib_modify_qp(qp, attr, + IB_QP_STATE | IB_QP_ACCESS_FLAGS | IB_QP_PORT | + IB_QP_PKEY_INDEX); + + kfree(attr); + return ret; +} + +/** + * srpt_ch_qp_rtr - change the state of a channel to 'ready to receive' (RTR) + * @ch: channel of the queue pair. + * @qp: queue pair to change the state of. + * + * Returns zero upon success and a negative value upon failure. + * + * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system. + * If this structure ever becomes larger, it might be necessary to allocate + * it dynamically instead of on the stack. + */ +static int srpt_ch_qp_rtr(struct srpt_rdma_ch *ch, struct ib_qp *qp) +{ + struct ib_qp_attr qp_attr; + int attr_mask; + int ret; + + WARN_ON_ONCE(ch->using_rdma_cm); + + qp_attr.qp_state = IB_QPS_RTR; + ret = ib_cm_init_qp_attr(ch->ib_cm.cm_id, &qp_attr, &attr_mask); + if (ret) + goto out; + + qp_attr.max_dest_rd_atomic = 4; + + ret = ib_modify_qp(qp, &qp_attr, attr_mask); + +out: + return ret; +} + +/** + * srpt_ch_qp_rts - change the state of a channel to 'ready to send' (RTS) + * @ch: channel of the queue pair. + * @qp: queue pair to change the state of. + * + * Returns zero upon success and a negative value upon failure. + * + * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system. + * If this structure ever becomes larger, it might be necessary to allocate + * it dynamically instead of on the stack. + */ +static int srpt_ch_qp_rts(struct srpt_rdma_ch *ch, struct ib_qp *qp) +{ + struct ib_qp_attr qp_attr; + int attr_mask; + int ret; + + qp_attr.qp_state = IB_QPS_RTS; + ret = ib_cm_init_qp_attr(ch->ib_cm.cm_id, &qp_attr, &attr_mask); + if (ret) + goto out; + + qp_attr.max_rd_atomic = 4; + + ret = ib_modify_qp(qp, &qp_attr, attr_mask); + +out: + return ret; +} + +/** + * srpt_ch_qp_err - set the channel queue pair state to 'error' + * @ch: SRPT RDMA channel. + */ +static int srpt_ch_qp_err(struct srpt_rdma_ch *ch) +{ + struct ib_qp_attr qp_attr; + + qp_attr.qp_state = IB_QPS_ERR; + return ib_modify_qp(ch->qp, &qp_attr, IB_QP_STATE); +} + +/** + * srpt_get_send_ioctx - obtain an I/O context for sending to the initiator + * @ch: SRPT RDMA channel. + */ +static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch) +{ + struct srpt_send_ioctx *ioctx; + int tag, cpu; + + BUG_ON(!ch); + + tag = sbitmap_queue_get(&ch->sess->sess_tag_pool, &cpu); + if (tag < 0) + return NULL; + + ioctx = ch->ioctx_ring[tag]; + BUG_ON(ioctx->ch != ch); + ioctx->state = SRPT_STATE_NEW; + WARN_ON_ONCE(ioctx->recv_ioctx); + ioctx->n_rdma = 0; + ioctx->n_rw_ctx = 0; + ioctx->queue_status_only = false; + /* + * transport_init_se_cmd() does not initialize all fields, so do it + * here. + */ + memset(&ioctx->cmd, 0, sizeof(ioctx->cmd)); + memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data)); + ioctx->cmd.map_tag = tag; + ioctx->cmd.map_cpu = cpu; + + return ioctx; +} + +/** + * srpt_abort_cmd - abort a SCSI command + * @ioctx: I/O context associated with the SCSI command. + */ +static int srpt_abort_cmd(struct srpt_send_ioctx *ioctx) +{ + enum srpt_command_state state; + + BUG_ON(!ioctx); + + /* + * If the command is in a state where the target core is waiting for + * the ib_srpt driver, change the state to the next state. + */ + + state = ioctx->state; + switch (state) { + case SRPT_STATE_NEED_DATA: + ioctx->state = SRPT_STATE_DATA_IN; + break; + case SRPT_STATE_CMD_RSP_SENT: + case SRPT_STATE_MGMT_RSP_SENT: + ioctx->state = SRPT_STATE_DONE; + break; + default: + WARN_ONCE(true, "%s: unexpected I/O context state %d\n", + __func__, state); + break; + } + + pr_debug("Aborting cmd with state %d -> %d and tag %lld\n", state, + ioctx->state, ioctx->cmd.tag); + + switch (state) { + case SRPT_STATE_NEW: + case SRPT_STATE_DATA_IN: + case SRPT_STATE_MGMT: + case SRPT_STATE_DONE: + /* + * Do nothing - defer abort processing until + * srpt_queue_response() is invoked. + */ + break; + case SRPT_STATE_NEED_DATA: + pr_debug("tag %#llx: RDMA read error\n", ioctx->cmd.tag); + transport_generic_request_failure(&ioctx->cmd, + TCM_CHECK_CONDITION_ABORT_CMD); + break; + case SRPT_STATE_CMD_RSP_SENT: + /* + * SRP_RSP sending failed or the SRP_RSP send completion has + * not been received in time. + */ + transport_generic_free_cmd(&ioctx->cmd, 0); + break; + case SRPT_STATE_MGMT_RSP_SENT: + transport_generic_free_cmd(&ioctx->cmd, 0); + break; + default: + WARN(1, "Unexpected command state (%d)", state); + break; + } + + return state; +} + +/** + * srpt_rdma_read_done - RDMA read completion callback + * @cq: Completion queue. + * @wc: Work completion. + * + * XXX: what is now target_execute_cmd used to be asynchronous, and unmapping + * the data that has been transferred via IB RDMA had to be postponed until the + * check_stop_free() callback. None of this is necessary anymore and needs to + * be cleaned up. + */ +static void srpt_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct srpt_rdma_ch *ch = wc->qp->qp_context; + struct srpt_send_ioctx *ioctx = + container_of(wc->wr_cqe, struct srpt_send_ioctx, rdma_cqe); + + WARN_ON(ioctx->n_rdma <= 0); + atomic_add(ioctx->n_rdma, &ch->sq_wr_avail); + ioctx->n_rdma = 0; + + if (unlikely(wc->status != IB_WC_SUCCESS)) { + pr_info("RDMA_READ for ioctx 0x%p failed with status %d\n", + ioctx, wc->status); + srpt_abort_cmd(ioctx); + return; + } + + if (srpt_test_and_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA, + SRPT_STATE_DATA_IN)) + target_execute_cmd(&ioctx->cmd); + else + pr_err("%s[%d]: wrong state = %d\n", __func__, + __LINE__, ioctx->state); +} + +/** + * srpt_build_cmd_rsp - build a SRP_RSP response + * @ch: RDMA channel through which the request has been received. + * @ioctx: I/O context associated with the SRP_CMD request. The response will + * be built in the buffer ioctx->buf points at and hence this function will + * overwrite the request data. + * @tag: tag of the request for which this response is being generated. + * @status: value for the STATUS field of the SRP_RSP information unit. + * + * Returns the size in bytes of the SRP_RSP response. + * + * An SRP_RSP response contains a SCSI status or service response. See also + * section 6.9 in the SRP r16a document for the format of an SRP_RSP + * response. See also SPC-2 for more information about sense data. + */ +static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx, u64 tag, + int status) +{ + struct se_cmd *cmd = &ioctx->cmd; + struct srp_rsp *srp_rsp; + const u8 *sense_data; + int sense_data_len, max_sense_len; + u32 resid = cmd->residual_count; + + /* + * The lowest bit of all SAM-3 status codes is zero (see also + * paragraph 5.3 in SAM-3). + */ + WARN_ON(status & 1); + + srp_rsp = ioctx->ioctx.buf; + BUG_ON(!srp_rsp); + + sense_data = ioctx->sense_data; + sense_data_len = ioctx->cmd.scsi_sense_length; + WARN_ON(sense_data_len > sizeof(ioctx->sense_data)); + + memset(srp_rsp, 0, sizeof(*srp_rsp)); + srp_rsp->opcode = SRP_RSP; + srp_rsp->req_lim_delta = + cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0)); + srp_rsp->tag = tag; + srp_rsp->status = status; + + if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) { + if (cmd->data_direction == DMA_TO_DEVICE) { + /* residual data from an underflow write */ + srp_rsp->flags = SRP_RSP_FLAG_DOUNDER; + srp_rsp->data_out_res_cnt = cpu_to_be32(resid); + } else if (cmd->data_direction == DMA_FROM_DEVICE) { + /* residual data from an underflow read */ + srp_rsp->flags = SRP_RSP_FLAG_DIUNDER; + srp_rsp->data_in_res_cnt = cpu_to_be32(resid); + } + } else if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) { + if (cmd->data_direction == DMA_TO_DEVICE) { + /* residual data from an overflow write */ + srp_rsp->flags = SRP_RSP_FLAG_DOOVER; + srp_rsp->data_out_res_cnt = cpu_to_be32(resid); + } else if (cmd->data_direction == DMA_FROM_DEVICE) { + /* residual data from an overflow read */ + srp_rsp->flags = SRP_RSP_FLAG_DIOVER; + srp_rsp->data_in_res_cnt = cpu_to_be32(resid); + } + } + + if (sense_data_len) { + BUILD_BUG_ON(MIN_MAX_RSP_SIZE <= sizeof(*srp_rsp)); + max_sense_len = ch->max_ti_iu_len - sizeof(*srp_rsp); + if (sense_data_len > max_sense_len) { + pr_warn("truncated sense data from %d to %d bytes\n", + sense_data_len, max_sense_len); + sense_data_len = max_sense_len; + } + + srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID; + srp_rsp->sense_data_len = cpu_to_be32(sense_data_len); + memcpy(srp_rsp + 1, sense_data, sense_data_len); + } + + return sizeof(*srp_rsp) + sense_data_len; +} + +/** + * srpt_build_tskmgmt_rsp - build a task management response + * @ch: RDMA channel through which the request has been received. + * @ioctx: I/O context in which the SRP_RSP response will be built. + * @rsp_code: RSP_CODE that will be stored in the response. + * @tag: Tag of the request for which this response is being generated. + * + * Returns the size in bytes of the SRP_RSP response. + * + * An SRP_RSP response contains a SCSI status or service response. See also + * section 6.9 in the SRP r16a document for the format of an SRP_RSP + * response. + */ +static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx, + u8 rsp_code, u64 tag) +{ + struct srp_rsp *srp_rsp; + int resp_data_len; + int resp_len; + + resp_data_len = 4; + resp_len = sizeof(*srp_rsp) + resp_data_len; + + srp_rsp = ioctx->ioctx.buf; + BUG_ON(!srp_rsp); + memset(srp_rsp, 0, sizeof(*srp_rsp)); + + srp_rsp->opcode = SRP_RSP; + srp_rsp->req_lim_delta = + cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0)); + srp_rsp->tag = tag; + + srp_rsp->flags |= SRP_RSP_FLAG_RSPVALID; + srp_rsp->resp_data_len = cpu_to_be32(resp_data_len); + srp_rsp->data[3] = rsp_code; + + return resp_len; +} + +static int srpt_check_stop_free(struct se_cmd *cmd) +{ + struct srpt_send_ioctx *ioctx = container_of(cmd, + struct srpt_send_ioctx, cmd); + + return target_put_sess_cmd(&ioctx->cmd); +} + +/** + * srpt_handle_cmd - process a SRP_CMD information unit + * @ch: SRPT RDMA channel. + * @recv_ioctx: Receive I/O context. + * @send_ioctx: Send I/O context. + */ +static void srpt_handle_cmd(struct srpt_rdma_ch *ch, + struct srpt_recv_ioctx *recv_ioctx, + struct srpt_send_ioctx *send_ioctx) +{ + struct se_cmd *cmd; + struct srp_cmd *srp_cmd; + struct scatterlist *sg = NULL; + unsigned sg_cnt = 0; + u64 data_len; + enum dma_data_direction dir; + int rc; + + BUG_ON(!send_ioctx); + + srp_cmd = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset; + cmd = &send_ioctx->cmd; + cmd->tag = srp_cmd->tag; + + switch (srp_cmd->task_attr) { + case SRP_CMD_SIMPLE_Q: + cmd->sam_task_attr = TCM_SIMPLE_TAG; + break; + case SRP_CMD_ORDERED_Q: + default: + cmd->sam_task_attr = TCM_ORDERED_TAG; + break; + case SRP_CMD_HEAD_OF_Q: + cmd->sam_task_attr = TCM_HEAD_TAG; + break; + case SRP_CMD_ACA: + cmd->sam_task_attr = TCM_ACA_TAG; + break; + } + + rc = srpt_get_desc_tbl(recv_ioctx, send_ioctx, srp_cmd, &dir, + &sg, &sg_cnt, &data_len, ch->imm_data_offset); + if (rc) { + if (rc != -EAGAIN) { + pr_err("0x%llx: parsing SRP descriptor table failed.\n", + srp_cmd->tag); + } + goto busy; + } + + rc = target_submit_cmd_map_sgls(cmd, ch->sess, srp_cmd->cdb, + &send_ioctx->sense_data[0], + scsilun_to_int(&srp_cmd->lun), data_len, + TCM_SIMPLE_TAG, dir, TARGET_SCF_ACK_KREF, + sg, sg_cnt, NULL, 0, NULL, 0); + if (rc != 0) { + pr_debug("target_submit_cmd() returned %d for tag %#llx\n", rc, + srp_cmd->tag); + goto busy; + } + return; + +busy: + target_send_busy(cmd); +} + +static int srp_tmr_to_tcm(int fn) +{ + switch (fn) { + case SRP_TSK_ABORT_TASK: + return TMR_ABORT_TASK; + case SRP_TSK_ABORT_TASK_SET: + return TMR_ABORT_TASK_SET; + case SRP_TSK_CLEAR_TASK_SET: + return TMR_CLEAR_TASK_SET; + case SRP_TSK_LUN_RESET: + return TMR_LUN_RESET; + case SRP_TSK_CLEAR_ACA: + return TMR_CLEAR_ACA; + default: + return -1; + } +} + +/** + * srpt_handle_tsk_mgmt - process a SRP_TSK_MGMT information unit + * @ch: SRPT RDMA channel. + * @recv_ioctx: Receive I/O context. + * @send_ioctx: Send I/O context. + * + * Returns 0 if and only if the request will be processed by the target core. + * + * For more information about SRP_TSK_MGMT information units, see also section + * 6.7 in the SRP r16a document. + */ +static void srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch, + struct srpt_recv_ioctx *recv_ioctx, + struct srpt_send_ioctx *send_ioctx) +{ + struct srp_tsk_mgmt *srp_tsk; + struct se_cmd *cmd; + struct se_session *sess = ch->sess; + int tcm_tmr; + int rc; + + BUG_ON(!send_ioctx); + + srp_tsk = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset; + cmd = &send_ioctx->cmd; + + pr_debug("recv tsk_mgmt fn %d for task_tag %lld and cmd tag %lld ch %p sess %p\n", + srp_tsk->tsk_mgmt_func, srp_tsk->task_tag, srp_tsk->tag, ch, + ch->sess); + + srpt_set_cmd_state(send_ioctx, SRPT_STATE_MGMT); + send_ioctx->cmd.tag = srp_tsk->tag; + tcm_tmr = srp_tmr_to_tcm(srp_tsk->tsk_mgmt_func); + rc = target_submit_tmr(&send_ioctx->cmd, sess, NULL, + scsilun_to_int(&srp_tsk->lun), srp_tsk, tcm_tmr, + GFP_KERNEL, srp_tsk->task_tag, + TARGET_SCF_ACK_KREF); + if (rc != 0) { + send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED; + cmd->se_tfo->queue_tm_rsp(cmd); + } + return; +} + +/** + * srpt_handle_new_iu - process a newly received information unit + * @ch: RDMA channel through which the information unit has been received. + * @recv_ioctx: Receive I/O context associated with the information unit. + */ +static bool +srpt_handle_new_iu(struct srpt_rdma_ch *ch, struct srpt_recv_ioctx *recv_ioctx) +{ + struct srpt_send_ioctx *send_ioctx = NULL; + struct srp_cmd *srp_cmd; + bool res = false; + u8 opcode; + + BUG_ON(!ch); + BUG_ON(!recv_ioctx); + + if (unlikely(ch->state == CH_CONNECTING)) + goto push; + + ib_dma_sync_single_for_cpu(ch->sport->sdev->device, + recv_ioctx->ioctx.dma, + recv_ioctx->ioctx.offset + srp_max_req_size, + DMA_FROM_DEVICE); + + srp_cmd = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset; + opcode = srp_cmd->opcode; + if (opcode == SRP_CMD || opcode == SRP_TSK_MGMT) { + send_ioctx = srpt_get_send_ioctx(ch); + if (unlikely(!send_ioctx)) + goto push; + } + + if (!list_empty(&recv_ioctx->wait_list)) { + WARN_ON_ONCE(!ch->processing_wait_list); + list_del_init(&recv_ioctx->wait_list); + } + + switch (opcode) { + case SRP_CMD: + srpt_handle_cmd(ch, recv_ioctx, send_ioctx); + break; + case SRP_TSK_MGMT: + srpt_handle_tsk_mgmt(ch, recv_ioctx, send_ioctx); + break; + case SRP_I_LOGOUT: + pr_err("Not yet implemented: SRP_I_LOGOUT\n"); + break; + case SRP_CRED_RSP: + pr_debug("received SRP_CRED_RSP\n"); + break; + case SRP_AER_RSP: + pr_debug("received SRP_AER_RSP\n"); + break; + case SRP_RSP: + pr_err("Received SRP_RSP\n"); + break; + default: + pr_err("received IU with unknown opcode 0x%x\n", opcode); + break; + } + + if (!send_ioctx || !send_ioctx->recv_ioctx) + srpt_post_recv(ch->sport->sdev, ch, recv_ioctx); + res = true; + +out: + return res; + +push: + if (list_empty(&recv_ioctx->wait_list)) { + WARN_ON_ONCE(ch->processing_wait_list); + list_add_tail(&recv_ioctx->wait_list, &ch->cmd_wait_list); + } + goto out; +} + +static void srpt_recv_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct srpt_rdma_ch *ch = wc->qp->qp_context; + struct srpt_recv_ioctx *ioctx = + container_of(wc->wr_cqe, struct srpt_recv_ioctx, ioctx.cqe); + + if (wc->status == IB_WC_SUCCESS) { + int req_lim; + + req_lim = atomic_dec_return(&ch->req_lim); + if (unlikely(req_lim < 0)) + pr_err("req_lim = %d < 0\n", req_lim); + ioctx->byte_len = wc->byte_len; + srpt_handle_new_iu(ch, ioctx); + } else { + pr_info_ratelimited("receiving failed for ioctx %p with status %d\n", + ioctx, wc->status); + } +} + +/* + * This function must be called from the context in which RDMA completions are + * processed because it accesses the wait list without protection against + * access from other threads. + */ +static void srpt_process_wait_list(struct srpt_rdma_ch *ch) +{ + struct srpt_recv_ioctx *recv_ioctx, *tmp; + + WARN_ON_ONCE(ch->state == CH_CONNECTING); + + if (list_empty(&ch->cmd_wait_list)) + return; + + WARN_ON_ONCE(ch->processing_wait_list); + ch->processing_wait_list = true; + list_for_each_entry_safe(recv_ioctx, tmp, &ch->cmd_wait_list, + wait_list) { + if (!srpt_handle_new_iu(ch, recv_ioctx)) + break; + } + ch->processing_wait_list = false; +} + +/** + * srpt_send_done - send completion callback + * @cq: Completion queue. + * @wc: Work completion. + * + * Note: Although this has not yet been observed during tests, at least in + * theory it is possible that the srpt_get_send_ioctx() call invoked by + * srpt_handle_new_iu() fails. This is possible because the req_lim_delta + * value in each response is set to one, and it is possible that this response + * makes the initiator send a new request before the send completion for that + * response has been processed. This could e.g. happen if the call to + * srpt_put_send_iotcx() is delayed because of a higher priority interrupt or + * if IB retransmission causes generation of the send completion to be + * delayed. Incoming information units for which srpt_get_send_ioctx() fails + * are queued on cmd_wait_list. The code below processes these delayed + * requests one at a time. + */ +static void srpt_send_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct srpt_rdma_ch *ch = wc->qp->qp_context; + struct srpt_send_ioctx *ioctx = + container_of(wc->wr_cqe, struct srpt_send_ioctx, ioctx.cqe); + enum srpt_command_state state; + + state = srpt_set_cmd_state(ioctx, SRPT_STATE_DONE); + + WARN_ON(state != SRPT_STATE_CMD_RSP_SENT && + state != SRPT_STATE_MGMT_RSP_SENT); + + atomic_add(1 + ioctx->n_rdma, &ch->sq_wr_avail); + + if (wc->status != IB_WC_SUCCESS) + pr_info("sending response for ioctx 0x%p failed with status %d\n", + ioctx, wc->status); + + if (state != SRPT_STATE_DONE) { + transport_generic_free_cmd(&ioctx->cmd, 0); + } else { + pr_err("IB completion has been received too late for wr_id = %u.\n", + ioctx->ioctx.index); + } + + srpt_process_wait_list(ch); +} + +/** + * srpt_create_ch_ib - create receive and send completion queues + * @ch: SRPT RDMA channel. + */ +static int srpt_create_ch_ib(struct srpt_rdma_ch *ch) +{ + struct ib_qp_init_attr *qp_init; + struct srpt_port *sport = ch->sport; + struct srpt_device *sdev = sport->sdev; + const struct ib_device_attr *attrs = &sdev->device->attrs; + int sq_size = sport->port_attrib.srp_sq_size; + int i, ret; + + WARN_ON(ch->rq_size < 1); + + ret = -ENOMEM; + qp_init = kzalloc(sizeof(*qp_init), GFP_KERNEL); + if (!qp_init) + goto out; + +retry: + ch->cq = ib_cq_pool_get(sdev->device, ch->rq_size + sq_size, -1, + IB_POLL_WORKQUEUE); + if (IS_ERR(ch->cq)) { + ret = PTR_ERR(ch->cq); + pr_err("failed to create CQ cqe= %d ret= %d\n", + ch->rq_size + sq_size, ret); + goto out; + } + ch->cq_size = ch->rq_size + sq_size; + + qp_init->qp_context = (void *)ch; + qp_init->event_handler + = (void(*)(struct ib_event *, void*))srpt_qp_event; + qp_init->send_cq = ch->cq; + qp_init->recv_cq = ch->cq; + qp_init->sq_sig_type = IB_SIGNAL_REQ_WR; + qp_init->qp_type = IB_QPT_RC; + /* + * We divide up our send queue size into half SEND WRs to send the + * completions, and half R/W contexts to actually do the RDMA + * READ/WRITE transfers. Note that we need to allocate CQ slots for + * both both, as RDMA contexts will also post completions for the + * RDMA READ case. + */ + qp_init->cap.max_send_wr = min(sq_size / 2, attrs->max_qp_wr); + qp_init->cap.max_rdma_ctxs = sq_size / 2; + qp_init->cap.max_send_sge = attrs->max_send_sge; + qp_init->cap.max_recv_sge = 1; + qp_init->port_num = ch->sport->port; + if (sdev->use_srq) + qp_init->srq = sdev->srq; + else + qp_init->cap.max_recv_wr = ch->rq_size; + + if (ch->using_rdma_cm) { + ret = rdma_create_qp(ch->rdma_cm.cm_id, sdev->pd, qp_init); + ch->qp = ch->rdma_cm.cm_id->qp; + } else { + ch->qp = ib_create_qp(sdev->pd, qp_init); + if (!IS_ERR(ch->qp)) { + ret = srpt_init_ch_qp(ch, ch->qp); + if (ret) + ib_destroy_qp(ch->qp); + } else { + ret = PTR_ERR(ch->qp); + } + } + if (ret) { + bool retry = sq_size > MIN_SRPT_SQ_SIZE; + + if (retry) { + pr_debug("failed to create queue pair with sq_size = %d (%d) - retrying\n", + sq_size, ret); + ib_cq_pool_put(ch->cq, ch->cq_size); + sq_size = max(sq_size / 2, MIN_SRPT_SQ_SIZE); + goto retry; + } else { + pr_err("failed to create queue pair with sq_size = %d (%d)\n", + sq_size, ret); + goto err_destroy_cq; + } + } + + atomic_set(&ch->sq_wr_avail, qp_init->cap.max_send_wr); + + pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d ch= %p\n", + __func__, ch->cq->cqe, qp_init->cap.max_send_sge, + qp_init->cap.max_send_wr, ch); + + if (!sdev->use_srq) + for (i = 0; i < ch->rq_size; i++) + srpt_post_recv(sdev, ch, ch->ioctx_recv_ring[i]); + +out: + kfree(qp_init); + return ret; + +err_destroy_cq: + ch->qp = NULL; + ib_cq_pool_put(ch->cq, ch->cq_size); + goto out; +} + +static void srpt_destroy_ch_ib(struct srpt_rdma_ch *ch) +{ + ib_destroy_qp(ch->qp); + ib_cq_pool_put(ch->cq, ch->cq_size); +} + +/** + * srpt_close_ch - close a RDMA channel + * @ch: SRPT RDMA channel. + * + * Make sure all resources associated with the channel will be deallocated at + * an appropriate time. + * + * Returns true if and only if the channel state has been modified into + * CH_DRAINING. + */ +static bool srpt_close_ch(struct srpt_rdma_ch *ch) +{ + int ret; + + if (!srpt_set_ch_state(ch, CH_DRAINING)) { + pr_debug("%s: already closed\n", ch->sess_name); + return false; + } + + kref_get(&ch->kref); + + ret = srpt_ch_qp_err(ch); + if (ret < 0) + pr_err("%s-%d: changing queue pair into error state failed: %d\n", + ch->sess_name, ch->qp->qp_num, ret); + + ret = srpt_zerolength_write(ch); + if (ret < 0) { + pr_err("%s-%d: queuing zero-length write failed: %d\n", + ch->sess_name, ch->qp->qp_num, ret); + if (srpt_set_ch_state(ch, CH_DISCONNECTED)) + schedule_work(&ch->release_work); + else + WARN_ON_ONCE(true); + } + + kref_put(&ch->kref, srpt_free_ch); + + return true; +} + +/* + * Change the channel state into CH_DISCONNECTING. If a channel has not yet + * reached the connected state, close it. If a channel is in the connected + * state, send a DREQ. If a DREQ has been received, send a DREP. Note: it is + * the responsibility of the caller to ensure that this function is not + * invoked concurrently with the code that accepts a connection. This means + * that this function must either be invoked from inside a CM callback + * function or that it must be invoked with the srpt_port.mutex held. + */ +static int srpt_disconnect_ch(struct srpt_rdma_ch *ch) +{ + int ret; + + if (!srpt_set_ch_state(ch, CH_DISCONNECTING)) + return -ENOTCONN; + + if (ch->using_rdma_cm) { + ret = rdma_disconnect(ch->rdma_cm.cm_id); + } else { + ret = ib_send_cm_dreq(ch->ib_cm.cm_id, NULL, 0); + if (ret < 0) + ret = ib_send_cm_drep(ch->ib_cm.cm_id, NULL, 0); + } + + if (ret < 0 && srpt_close_ch(ch)) + ret = 0; + + return ret; +} + +/* Send DREQ and wait for DREP. */ +static void srpt_disconnect_ch_sync(struct srpt_rdma_ch *ch) +{ + DECLARE_COMPLETION_ONSTACK(closed); + struct srpt_port *sport = ch->sport; + + pr_debug("ch %s-%d state %d\n", ch->sess_name, ch->qp->qp_num, + ch->state); + + ch->closed = &closed; + + mutex_lock(&sport->mutex); + srpt_disconnect_ch(ch); + mutex_unlock(&sport->mutex); + + while (wait_for_completion_timeout(&closed, 5 * HZ) == 0) + pr_info("%s(%s-%d state %d): still waiting ...\n", __func__, + ch->sess_name, ch->qp->qp_num, ch->state); + +} + +static void __srpt_close_all_ch(struct srpt_port *sport) +{ + struct srpt_nexus *nexus; + struct srpt_rdma_ch *ch; + + lockdep_assert_held(&sport->mutex); + + list_for_each_entry(nexus, &sport->nexus_list, entry) { + list_for_each_entry(ch, &nexus->ch_list, list) { + if (srpt_disconnect_ch(ch) >= 0) + pr_info("Closing channel %s-%d because target %s_%d has been disabled\n", + ch->sess_name, ch->qp->qp_num, + dev_name(&sport->sdev->device->dev), + sport->port); + srpt_close_ch(ch); + } + } +} + +/* + * Look up (i_port_id, t_port_id) in sport->nexus_list. Create an entry if + * it does not yet exist. + */ +static struct srpt_nexus *srpt_get_nexus(struct srpt_port *sport, + const u8 i_port_id[16], + const u8 t_port_id[16]) +{ + struct srpt_nexus *nexus = NULL, *tmp_nexus = NULL, *n; + + for (;;) { + mutex_lock(&sport->mutex); + list_for_each_entry(n, &sport->nexus_list, entry) { + if (memcmp(n->i_port_id, i_port_id, 16) == 0 && + memcmp(n->t_port_id, t_port_id, 16) == 0) { + nexus = n; + break; + } + } + if (!nexus && tmp_nexus) { + list_add_tail_rcu(&tmp_nexus->entry, + &sport->nexus_list); + swap(nexus, tmp_nexus); + } + mutex_unlock(&sport->mutex); + + if (nexus) + break; + tmp_nexus = kzalloc(sizeof(*nexus), GFP_KERNEL); + if (!tmp_nexus) { + nexus = ERR_PTR(-ENOMEM); + break; + } + INIT_LIST_HEAD(&tmp_nexus->ch_list); + memcpy(tmp_nexus->i_port_id, i_port_id, 16); + memcpy(tmp_nexus->t_port_id, t_port_id, 16); + } + + kfree(tmp_nexus); + + return nexus; +} + +static void srpt_set_enabled(struct srpt_port *sport, bool enabled) + __must_hold(&sport->mutex) +{ + lockdep_assert_held(&sport->mutex); + + if (sport->enabled == enabled) + return; + sport->enabled = enabled; + if (!enabled) + __srpt_close_all_ch(sport); +} + +static void srpt_drop_sport_ref(struct srpt_port *sport) +{ + if (atomic_dec_return(&sport->refcount) == 0 && sport->freed_channels) + complete(sport->freed_channels); +} + +static void srpt_free_ch(struct kref *kref) +{ + struct srpt_rdma_ch *ch = container_of(kref, struct srpt_rdma_ch, kref); + + srpt_drop_sport_ref(ch->sport); + kfree_rcu(ch, rcu); +} + +/* + * Shut down the SCSI target session, tell the connection manager to + * disconnect the associated RDMA channel, transition the QP to the error + * state and remove the channel from the channel list. This function is + * typically called from inside srpt_zerolength_write_done(). Concurrent + * srpt_zerolength_write() calls from inside srpt_close_ch() are possible + * as long as the channel is on sport->nexus_list. + */ +static void srpt_release_channel_work(struct work_struct *w) +{ + struct srpt_rdma_ch *ch; + struct srpt_device *sdev; + struct srpt_port *sport; + struct se_session *se_sess; + + ch = container_of(w, struct srpt_rdma_ch, release_work); + pr_debug("%s-%d\n", ch->sess_name, ch->qp->qp_num); + + sdev = ch->sport->sdev; + BUG_ON(!sdev); + + se_sess = ch->sess; + BUG_ON(!se_sess); + + target_sess_cmd_list_set_waiting(se_sess); + target_wait_for_sess_cmds(se_sess); + + target_remove_session(se_sess); + ch->sess = NULL; + + if (ch->using_rdma_cm) + rdma_destroy_id(ch->rdma_cm.cm_id); + else + ib_destroy_cm_id(ch->ib_cm.cm_id); + + sport = ch->sport; + mutex_lock(&sport->mutex); + list_del_rcu(&ch->list); + mutex_unlock(&sport->mutex); + + if (ch->closed) + complete(ch->closed); + + srpt_destroy_ch_ib(ch); + + srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring, + ch->sport->sdev, ch->rq_size, + ch->rsp_buf_cache, DMA_TO_DEVICE); + + kmem_cache_destroy(ch->rsp_buf_cache); + + srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_recv_ring, + sdev, ch->rq_size, + ch->req_buf_cache, DMA_FROM_DEVICE); + + kmem_cache_destroy(ch->req_buf_cache); + + kref_put(&ch->kref, srpt_free_ch); +} + +/** + * srpt_cm_req_recv - process the event IB_CM_REQ_RECEIVED + * @sdev: HCA through which the login request was received. + * @ib_cm_id: IB/CM connection identifier in case of IB/CM. + * @rdma_cm_id: RDMA/CM connection identifier in case of RDMA/CM. + * @port_num: Port through which the REQ message was received. + * @pkey: P_Key of the incoming connection. + * @req: SRP login request. + * @src_addr: GID (IB/CM) or IP address (RDMA/CM) of the port that submitted + * the login request. + * + * Ownership of the cm_id is transferred to the target session if this + * function returns zero. Otherwise the caller remains the owner of cm_id. + */ +static int srpt_cm_req_recv(struct srpt_device *const sdev, + struct ib_cm_id *ib_cm_id, + struct rdma_cm_id *rdma_cm_id, + u8 port_num, __be16 pkey, + const struct srp_login_req *req, + const char *src_addr) +{ + struct srpt_port *sport = &sdev->port[port_num - 1]; + struct srpt_nexus *nexus; + struct srp_login_rsp *rsp = NULL; + struct srp_login_rej *rej = NULL; + union { + struct rdma_conn_param rdma_cm; + struct ib_cm_rep_param ib_cm; + } *rep_param = NULL; + struct srpt_rdma_ch *ch = NULL; + char i_port_id[36]; + u32 it_iu_len; + int i, tag_num, tag_size, ret; + struct srpt_tpg *stpg; + + WARN_ON_ONCE(irqs_disabled()); + + it_iu_len = be32_to_cpu(req->req_it_iu_len); + + 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", + req->initiator_port_id, req->target_port_id, it_iu_len, + port_num, &sport->gid, be16_to_cpu(pkey)); + + nexus = srpt_get_nexus(sport, req->initiator_port_id, + req->target_port_id); + if (IS_ERR(nexus)) { + ret = PTR_ERR(nexus); + goto out; + } + + ret = -ENOMEM; + rsp = kzalloc(sizeof(*rsp), GFP_KERNEL); + rej = kzalloc(sizeof(*rej), GFP_KERNEL); + rep_param = kzalloc(sizeof(*rep_param), GFP_KERNEL); + if (!rsp || !rej || !rep_param) + goto out; + + ret = -EINVAL; + if (it_iu_len > srp_max_req_size || it_iu_len < 64) { + rej->reason = cpu_to_be32( + SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE); + pr_err("rejected SRP_LOGIN_REQ because its length (%d bytes) is out of range (%d .. %d)\n", + it_iu_len, 64, srp_max_req_size); + goto reject; + } + + if (!sport->enabled) { + rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_info("rejected SRP_LOGIN_REQ because target port %s_%d has not yet been enabled\n", + dev_name(&sport->sdev->device->dev), port_num); + goto reject; + } + + if (*(__be64 *)req->target_port_id != cpu_to_be64(srpt_service_guid) + || *(__be64 *)(req->target_port_id + 8) != + cpu_to_be64(srpt_service_guid)) { + rej->reason = cpu_to_be32( + SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL); + pr_err("rejected SRP_LOGIN_REQ because it has an invalid target port identifier.\n"); + goto reject; + } + + ret = -ENOMEM; + ch = kzalloc(sizeof(*ch), GFP_KERNEL); + if (!ch) { + rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_err("rejected SRP_LOGIN_REQ because out of memory.\n"); + goto reject; + } + + kref_init(&ch->kref); + ch->pkey = be16_to_cpu(pkey); + ch->nexus = nexus; + ch->zw_cqe.done = srpt_zerolength_write_done; + INIT_WORK(&ch->release_work, srpt_release_channel_work); + ch->sport = sport; + if (ib_cm_id) { + ch->ib_cm.cm_id = ib_cm_id; + ib_cm_id->context = ch; + } else { + ch->using_rdma_cm = true; + ch->rdma_cm.cm_id = rdma_cm_id; + rdma_cm_id->context = ch; + } + /* + * ch->rq_size should be at least as large as the initiator queue + * depth to avoid that the initiator driver has to report QUEUE_FULL + * to the SCSI mid-layer. + */ + ch->rq_size = min(MAX_SRPT_RQ_SIZE, sdev->device->attrs.max_qp_wr); + spin_lock_init(&ch->spinlock); + ch->state = CH_CONNECTING; + INIT_LIST_HEAD(&ch->cmd_wait_list); + ch->max_rsp_size = ch->sport->port_attrib.srp_max_rsp_size; + + ch->rsp_buf_cache = kmem_cache_create("srpt-rsp-buf", ch->max_rsp_size, + 512, 0, NULL); + if (!ch->rsp_buf_cache) + goto free_ch; + + ch->ioctx_ring = (struct srpt_send_ioctx **) + srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size, + sizeof(*ch->ioctx_ring[0]), + ch->rsp_buf_cache, 0, DMA_TO_DEVICE); + if (!ch->ioctx_ring) { + pr_err("rejected SRP_LOGIN_REQ because creating a new QP SQ ring failed.\n"); + rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + goto free_rsp_cache; + } + + for (i = 0; i < ch->rq_size; i++) + ch->ioctx_ring[i]->ch = ch; + if (!sdev->use_srq) { + u16 imm_data_offset = req->req_flags & SRP_IMMED_REQUESTED ? + be16_to_cpu(req->imm_data_offset) : 0; + u16 alignment_offset; + u32 req_sz; + + if (req->req_flags & SRP_IMMED_REQUESTED) + pr_debug("imm_data_offset = %d\n", + be16_to_cpu(req->imm_data_offset)); + if (imm_data_offset >= sizeof(struct srp_cmd)) { + ch->imm_data_offset = imm_data_offset; + rsp->rsp_flags |= SRP_LOGIN_RSP_IMMED_SUPP; + } else { + ch->imm_data_offset = 0; + } + alignment_offset = round_up(imm_data_offset, 512) - + imm_data_offset; + req_sz = alignment_offset + imm_data_offset + srp_max_req_size; + ch->req_buf_cache = kmem_cache_create("srpt-req-buf", req_sz, + 512, 0, NULL); + if (!ch->req_buf_cache) + goto free_rsp_ring; + + ch->ioctx_recv_ring = (struct srpt_recv_ioctx **) + srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size, + sizeof(*ch->ioctx_recv_ring[0]), + ch->req_buf_cache, + alignment_offset, + DMA_FROM_DEVICE); + if (!ch->ioctx_recv_ring) { + pr_err("rejected SRP_LOGIN_REQ because creating a new QP RQ ring failed.\n"); + rej->reason = + cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + goto free_recv_cache; + } + for (i = 0; i < ch->rq_size; i++) + INIT_LIST_HEAD(&ch->ioctx_recv_ring[i]->wait_list); + } + + ret = srpt_create_ch_ib(ch); + if (ret) { + rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_err("rejected SRP_LOGIN_REQ because creating a new RDMA channel failed.\n"); + goto free_recv_ring; + } + + strlcpy(ch->sess_name, src_addr, sizeof(ch->sess_name)); + snprintf(i_port_id, sizeof(i_port_id), "0x%016llx%016llx", + be64_to_cpu(*(__be64 *)nexus->i_port_id), + be64_to_cpu(*(__be64 *)(nexus->i_port_id + 8))); + + pr_debug("registering src addr %s or i_port_id %s\n", ch->sess_name, + i_port_id); + + tag_num = ch->rq_size; + tag_size = 1; /* ib_srpt does not use se_sess->sess_cmd_map */ + + if (sport->guid_id) { + mutex_lock(&sport->guid_id->mutex); + list_for_each_entry(stpg, &sport->guid_id->tpg_list, entry) { + if (!IS_ERR_OR_NULL(ch->sess)) + break; + ch->sess = target_setup_session(&stpg->tpg, tag_num, + tag_size, TARGET_PROT_NORMAL, + ch->sess_name, ch, NULL); + } + mutex_unlock(&sport->guid_id->mutex); + } + + if (sport->gid_id) { + mutex_lock(&sport->gid_id->mutex); + list_for_each_entry(stpg, &sport->gid_id->tpg_list, entry) { + if (!IS_ERR_OR_NULL(ch->sess)) + break; + ch->sess = target_setup_session(&stpg->tpg, tag_num, + tag_size, TARGET_PROT_NORMAL, i_port_id, + ch, NULL); + if (!IS_ERR_OR_NULL(ch->sess)) + break; + /* Retry without leading "0x" */ + ch->sess = target_setup_session(&stpg->tpg, tag_num, + tag_size, TARGET_PROT_NORMAL, + i_port_id + 2, ch, NULL); + } + mutex_unlock(&sport->gid_id->mutex); + } + + if (IS_ERR_OR_NULL(ch->sess)) { + WARN_ON_ONCE(ch->sess == NULL); + ret = PTR_ERR(ch->sess); + ch->sess = NULL; + pr_info("Rejected login for initiator %s: ret = %d.\n", + ch->sess_name, ret); + rej->reason = cpu_to_be32(ret == -ENOMEM ? + SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES : + SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED); + goto destroy_ib; + } + + /* + * Once a session has been created destruction of srpt_rdma_ch objects + * will decrement sport->refcount. Hence increment sport->refcount now. + */ + atomic_inc(&sport->refcount); + + mutex_lock(&sport->mutex); + + if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) { + struct srpt_rdma_ch *ch2; + + list_for_each_entry(ch2, &nexus->ch_list, list) { + if (srpt_disconnect_ch(ch2) < 0) + continue; + pr_info("Relogin - closed existing channel %s\n", + ch2->sess_name); + rsp->rsp_flags |= SRP_LOGIN_RSP_MULTICHAN_TERMINATED; + } + } else { + rsp->rsp_flags |= SRP_LOGIN_RSP_MULTICHAN_MAINTAINED; + } + + list_add_tail_rcu(&ch->list, &nexus->ch_list); + + if (!sport->enabled) { + rej->reason = cpu_to_be32( + SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_info("rejected SRP_LOGIN_REQ because target %s_%d is not enabled\n", + dev_name(&sdev->device->dev), port_num); + mutex_unlock(&sport->mutex); + ret = -EINVAL; + goto reject; + } + + mutex_unlock(&sport->mutex); + + ret = ch->using_rdma_cm ? 0 : srpt_ch_qp_rtr(ch, ch->qp); + if (ret) { + rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_err("rejected SRP_LOGIN_REQ because enabling RTR failed (error code = %d)\n", + ret); + goto reject; + } + + pr_debug("Establish connection sess=%p name=%s ch=%p\n", ch->sess, + ch->sess_name, ch); + + /* create srp_login_response */ + rsp->opcode = SRP_LOGIN_RSP; + rsp->tag = req->tag; + rsp->max_it_iu_len = cpu_to_be32(srp_max_req_size); + rsp->max_ti_iu_len = req->req_it_iu_len; + ch->max_ti_iu_len = it_iu_len; + rsp->buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT | + SRP_BUF_FORMAT_INDIRECT); + rsp->req_lim_delta = cpu_to_be32(ch->rq_size); + atomic_set(&ch->req_lim, ch->rq_size); + atomic_set(&ch->req_lim_delta, 0); + + /* create cm reply */ + if (ch->using_rdma_cm) { + rep_param->rdma_cm.private_data = (void *)rsp; + rep_param->rdma_cm.private_data_len = sizeof(*rsp); + rep_param->rdma_cm.rnr_retry_count = 7; + rep_param->rdma_cm.flow_control = 1; + rep_param->rdma_cm.responder_resources = 4; + rep_param->rdma_cm.initiator_depth = 4; + } else { + rep_param->ib_cm.qp_num = ch->qp->qp_num; + rep_param->ib_cm.private_data = (void *)rsp; + rep_param->ib_cm.private_data_len = sizeof(*rsp); + rep_param->ib_cm.rnr_retry_count = 7; + rep_param->ib_cm.flow_control = 1; + rep_param->ib_cm.failover_accepted = 0; + rep_param->ib_cm.srq = 1; + rep_param->ib_cm.responder_resources = 4; + rep_param->ib_cm.initiator_depth = 4; + } + + /* + * Hold the sport mutex while accepting a connection to avoid that + * srpt_disconnect_ch() is invoked concurrently with this code. + */ + mutex_lock(&sport->mutex); + if (sport->enabled && ch->state == CH_CONNECTING) { + if (ch->using_rdma_cm) + ret = rdma_accept(rdma_cm_id, &rep_param->rdma_cm); + else + ret = ib_send_cm_rep(ib_cm_id, &rep_param->ib_cm); + } else { + ret = -EINVAL; + } + mutex_unlock(&sport->mutex); + + switch (ret) { + case 0: + break; + case -EINVAL: + goto reject; + default: + rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_err("sending SRP_LOGIN_REQ response failed (error code = %d)\n", + ret); + goto reject; + } + + goto out; + +destroy_ib: + srpt_destroy_ch_ib(ch); + +free_recv_ring: + srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_recv_ring, + ch->sport->sdev, ch->rq_size, + ch->req_buf_cache, DMA_FROM_DEVICE); + +free_recv_cache: + kmem_cache_destroy(ch->req_buf_cache); + +free_rsp_ring: + srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring, + ch->sport->sdev, ch->rq_size, + ch->rsp_buf_cache, DMA_TO_DEVICE); + +free_rsp_cache: + kmem_cache_destroy(ch->rsp_buf_cache); + +free_ch: + if (rdma_cm_id) + rdma_cm_id->context = NULL; + else + ib_cm_id->context = NULL; + kfree(ch); + ch = NULL; + + WARN_ON_ONCE(ret == 0); + +reject: + pr_info("Rejecting login with reason %#x\n", be32_to_cpu(rej->reason)); + rej->opcode = SRP_LOGIN_REJ; + rej->tag = req->tag; + rej->buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT | + SRP_BUF_FORMAT_INDIRECT); + + if (rdma_cm_id) + rdma_reject(rdma_cm_id, rej, sizeof(*rej), + IB_CM_REJ_CONSUMER_DEFINED); + else + ib_send_cm_rej(ib_cm_id, IB_CM_REJ_CONSUMER_DEFINED, NULL, 0, + rej, sizeof(*rej)); + + if (ch && ch->sess) { + srpt_close_ch(ch); + /* + * Tell the caller not to free cm_id since + * srpt_release_channel_work() will do that. + */ + ret = 0; + } + +out: + kfree(rep_param); + kfree(rsp); + kfree(rej); + + return ret; +} + +static int srpt_ib_cm_req_recv(struct ib_cm_id *cm_id, + const struct ib_cm_req_event_param *param, + void *private_data) +{ + char sguid[40]; + + srpt_format_guid(sguid, sizeof(sguid), + ¶m->primary_path->dgid.global.interface_id); + + return srpt_cm_req_recv(cm_id->context, cm_id, NULL, param->port, + param->primary_path->pkey, + private_data, sguid); +} + +static int srpt_rdma_cm_req_recv(struct rdma_cm_id *cm_id, + struct rdma_cm_event *event) +{ + struct srpt_device *sdev; + struct srp_login_req req; + const struct srp_login_req_rdma *req_rdma; + struct sa_path_rec *path_rec = cm_id->route.path_rec; + char src_addr[40]; + + sdev = ib_get_client_data(cm_id->device, &srpt_client); + if (!sdev) + return -ECONNREFUSED; + + if (event->param.conn.private_data_len < sizeof(*req_rdma)) + return -EINVAL; + + /* Transform srp_login_req_rdma into srp_login_req. */ + req_rdma = event->param.conn.private_data; + memset(&req, 0, sizeof(req)); + req.opcode = req_rdma->opcode; + req.tag = req_rdma->tag; + req.req_it_iu_len = req_rdma->req_it_iu_len; + req.req_buf_fmt = req_rdma->req_buf_fmt; + req.req_flags = req_rdma->req_flags; + memcpy(req.initiator_port_id, req_rdma->initiator_port_id, 16); + memcpy(req.target_port_id, req_rdma->target_port_id, 16); + req.imm_data_offset = req_rdma->imm_data_offset; + + snprintf(src_addr, sizeof(src_addr), "%pIS", + &cm_id->route.addr.src_addr); + + return srpt_cm_req_recv(sdev, NULL, cm_id, cm_id->port_num, + path_rec ? path_rec->pkey : 0, &req, src_addr); +} + +static void srpt_cm_rej_recv(struct srpt_rdma_ch *ch, + enum ib_cm_rej_reason reason, + const u8 *private_data, + u8 private_data_len) +{ + char *priv = NULL; + int i; + + if (private_data_len && (priv = kmalloc(private_data_len * 3 + 1, + GFP_KERNEL))) { + for (i = 0; i < private_data_len; i++) + sprintf(priv + 3 * i, " %02x", private_data[i]); + } + pr_info("Received CM REJ for ch %s-%d; reason %d%s%s.\n", + ch->sess_name, ch->qp->qp_num, reason, private_data_len ? + "; private data" : "", priv ? priv : " (?)"); + kfree(priv); +} + +/** + * srpt_cm_rtu_recv - process an IB_CM_RTU_RECEIVED or USER_ESTABLISHED event + * @ch: SRPT RDMA channel. + * + * An RTU (ready to use) message indicates that the connection has been + * established and that the recipient may begin transmitting. + */ +static void srpt_cm_rtu_recv(struct srpt_rdma_ch *ch) +{ + int ret; + + ret = ch->using_rdma_cm ? 0 : srpt_ch_qp_rts(ch, ch->qp); + if (ret < 0) { + pr_err("%s-%d: QP transition to RTS failed\n", ch->sess_name, + ch->qp->qp_num); + srpt_close_ch(ch); + return; + } + + /* + * Note: calling srpt_close_ch() if the transition to the LIVE state + * fails is not necessary since that means that that function has + * already been invoked from another thread. + */ + if (!srpt_set_ch_state(ch, CH_LIVE)) { + pr_err("%s-%d: channel transition to LIVE state failed\n", + ch->sess_name, ch->qp->qp_num); + return; + } + + /* Trigger wait list processing. */ + ret = srpt_zerolength_write(ch); + WARN_ONCE(ret < 0, "%d\n", ret); +} + +/** + * srpt_cm_handler - IB connection manager callback function + * @cm_id: IB/CM connection identifier. + * @event: IB/CM event. + * + * A non-zero return value will cause the caller destroy the CM ID. + * + * Note: srpt_cm_handler() must only return a non-zero value when transferring + * ownership of the cm_id to a channel by srpt_cm_req_recv() failed. Returning + * a non-zero value in any other case will trigger a race with the + * ib_destroy_cm_id() call in srpt_release_channel(). + */ +static int srpt_cm_handler(struct ib_cm_id *cm_id, + const struct ib_cm_event *event) +{ + struct srpt_rdma_ch *ch = cm_id->context; + int ret; + + ret = 0; + switch (event->event) { + case IB_CM_REQ_RECEIVED: + ret = srpt_ib_cm_req_recv(cm_id, &event->param.req_rcvd, + event->private_data); + break; + case IB_CM_REJ_RECEIVED: + srpt_cm_rej_recv(ch, event->param.rej_rcvd.reason, + event->private_data, + IB_CM_REJ_PRIVATE_DATA_SIZE); + break; + case IB_CM_RTU_RECEIVED: + case IB_CM_USER_ESTABLISHED: + srpt_cm_rtu_recv(ch); + break; + case IB_CM_DREQ_RECEIVED: + srpt_disconnect_ch(ch); + break; + case IB_CM_DREP_RECEIVED: + pr_info("Received CM DREP message for ch %s-%d.\n", + ch->sess_name, ch->qp->qp_num); + srpt_close_ch(ch); + break; + case IB_CM_TIMEWAIT_EXIT: + pr_info("Received CM TimeWait exit for ch %s-%d.\n", + ch->sess_name, ch->qp->qp_num); + srpt_close_ch(ch); + break; + case IB_CM_REP_ERROR: + pr_info("Received CM REP error for ch %s-%d.\n", ch->sess_name, + ch->qp->qp_num); + break; + case IB_CM_DREQ_ERROR: + pr_info("Received CM DREQ ERROR event.\n"); + break; + case IB_CM_MRA_RECEIVED: + pr_info("Received CM MRA event\n"); + break; + default: + pr_err("received unrecognized CM event %d\n", event->event); + break; + } + + return ret; +} + +static int srpt_rdma_cm_handler(struct rdma_cm_id *cm_id, + struct rdma_cm_event *event) +{ + struct srpt_rdma_ch *ch = cm_id->context; + int ret = 0; + + switch (event->event) { + case RDMA_CM_EVENT_CONNECT_REQUEST: + ret = srpt_rdma_cm_req_recv(cm_id, event); + break; + case RDMA_CM_EVENT_REJECTED: + srpt_cm_rej_recv(ch, event->status, + event->param.conn.private_data, + event->param.conn.private_data_len); + break; + case RDMA_CM_EVENT_ESTABLISHED: + srpt_cm_rtu_recv(ch); + break; + case RDMA_CM_EVENT_DISCONNECTED: + if (ch->state < CH_DISCONNECTING) + srpt_disconnect_ch(ch); + else + srpt_close_ch(ch); + break; + case RDMA_CM_EVENT_TIMEWAIT_EXIT: + srpt_close_ch(ch); + break; + case RDMA_CM_EVENT_UNREACHABLE: + pr_info("Received CM REP error for ch %s-%d.\n", ch->sess_name, + ch->qp->qp_num); + break; + case RDMA_CM_EVENT_DEVICE_REMOVAL: + case RDMA_CM_EVENT_ADDR_CHANGE: + break; + default: + pr_err("received unrecognized RDMA CM event %d\n", + event->event); + break; + } + + return ret; +} + +/* + * srpt_write_pending - Start data transfer from initiator to target (write). + */ +static int srpt_write_pending(struct se_cmd *se_cmd) +{ + struct srpt_send_ioctx *ioctx = + container_of(se_cmd, struct srpt_send_ioctx, cmd); + struct srpt_rdma_ch *ch = ioctx->ch; + struct ib_send_wr *first_wr = NULL; + struct ib_cqe *cqe = &ioctx->rdma_cqe; + enum srpt_command_state new_state; + int ret, i; + + if (ioctx->recv_ioctx) { + srpt_set_cmd_state(ioctx, SRPT_STATE_DATA_IN); + target_execute_cmd(&ioctx->cmd); + return 0; + } + + new_state = srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA); + WARN_ON(new_state == SRPT_STATE_DONE); + + if (atomic_sub_return(ioctx->n_rdma, &ch->sq_wr_avail) < 0) { + pr_warn("%s: IB send queue full (needed %d)\n", + __func__, ioctx->n_rdma); + ret = -ENOMEM; + goto out_undo; + } + + cqe->done = srpt_rdma_read_done; + for (i = ioctx->n_rw_ctx - 1; i >= 0; i--) { + struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i]; + + first_wr = rdma_rw_ctx_wrs(&ctx->rw, ch->qp, ch->sport->port, + cqe, first_wr); + cqe = NULL; + } + + ret = ib_post_send(ch->qp, first_wr, NULL); + if (ret) { + pr_err("%s: ib_post_send() returned %d for %d (avail: %d)\n", + __func__, ret, ioctx->n_rdma, + atomic_read(&ch->sq_wr_avail)); + goto out_undo; + } + + return 0; +out_undo: + atomic_add(ioctx->n_rdma, &ch->sq_wr_avail); + return ret; +} + +static u8 tcm_to_srp_tsk_mgmt_status(const int tcm_mgmt_status) +{ + switch (tcm_mgmt_status) { + case TMR_FUNCTION_COMPLETE: + return SRP_TSK_MGMT_SUCCESS; + case TMR_FUNCTION_REJECTED: + return SRP_TSK_MGMT_FUNC_NOT_SUPP; + } + return SRP_TSK_MGMT_FAILED; +} + +/** + * srpt_queue_response - transmit the response to a SCSI command + * @cmd: SCSI target command. + * + * Callback function called by the TCM core. Must not block since it can be + * invoked on the context of the IB completion handler. + */ +static void srpt_queue_response(struct se_cmd *cmd) +{ + struct srpt_send_ioctx *ioctx = + container_of(cmd, struct srpt_send_ioctx, cmd); + struct srpt_rdma_ch *ch = ioctx->ch; + struct srpt_device *sdev = ch->sport->sdev; + struct ib_send_wr send_wr, *first_wr = &send_wr; + struct ib_sge sge; + enum srpt_command_state state; + int resp_len, ret, i; + u8 srp_tm_status; + + state = ioctx->state; + switch (state) { + case SRPT_STATE_NEW: + case SRPT_STATE_DATA_IN: + ioctx->state = SRPT_STATE_CMD_RSP_SENT; + break; + case SRPT_STATE_MGMT: + ioctx->state = SRPT_STATE_MGMT_RSP_SENT; + break; + default: + WARN(true, "ch %p; cmd %d: unexpected command state %d\n", + ch, ioctx->ioctx.index, ioctx->state); + break; + } + + if (WARN_ON_ONCE(state == SRPT_STATE_CMD_RSP_SENT)) + return; + + /* For read commands, transfer the data to the initiator. */ + if (ioctx->cmd.data_direction == DMA_FROM_DEVICE && + ioctx->cmd.data_length && + !ioctx->queue_status_only) { + for (i = ioctx->n_rw_ctx - 1; i >= 0; i--) { + struct srpt_rw_ctx *ctx = &ioctx->rw_ctxs[i]; + + first_wr = rdma_rw_ctx_wrs(&ctx->rw, ch->qp, + ch->sport->port, NULL, first_wr); + } + } + + if (state != SRPT_STATE_MGMT) + resp_len = srpt_build_cmd_rsp(ch, ioctx, ioctx->cmd.tag, + cmd->scsi_status); + else { + srp_tm_status + = tcm_to_srp_tsk_mgmt_status(cmd->se_tmr_req->response); + resp_len = srpt_build_tskmgmt_rsp(ch, ioctx, srp_tm_status, + ioctx->cmd.tag); + } + + atomic_inc(&ch->req_lim); + + if (unlikely(atomic_sub_return(1 + ioctx->n_rdma, + &ch->sq_wr_avail) < 0)) { + pr_warn("%s: IB send queue full (needed %d)\n", + __func__, ioctx->n_rdma); + ret = -ENOMEM; + goto out; + } + + ib_dma_sync_single_for_device(sdev->device, ioctx->ioctx.dma, resp_len, + DMA_TO_DEVICE); + + sge.addr = ioctx->ioctx.dma; + sge.length = resp_len; + sge.lkey = sdev->lkey; + + ioctx->ioctx.cqe.done = srpt_send_done; + send_wr.next = NULL; + send_wr.wr_cqe = &ioctx->ioctx.cqe; + send_wr.sg_list = &sge; + send_wr.num_sge = 1; + send_wr.opcode = IB_WR_SEND; + send_wr.send_flags = IB_SEND_SIGNALED; + + ret = ib_post_send(ch->qp, first_wr, NULL); + if (ret < 0) { + pr_err("%s: sending cmd response failed for tag %llu (%d)\n", + __func__, ioctx->cmd.tag, ret); + goto out; + } + + return; + +out: + atomic_add(1 + ioctx->n_rdma, &ch->sq_wr_avail); + atomic_dec(&ch->req_lim); + srpt_set_cmd_state(ioctx, SRPT_STATE_DONE); + target_put_sess_cmd(&ioctx->cmd); +} + +static int srpt_queue_data_in(struct se_cmd *cmd) +{ + srpt_queue_response(cmd); + return 0; +} + +static void srpt_queue_tm_rsp(struct se_cmd *cmd) +{ + srpt_queue_response(cmd); +} + +/* + * This function is called for aborted commands if no response is sent to the + * initiator. Make sure that the credits freed by aborting a command are + * returned to the initiator the next time a response is sent by incrementing + * ch->req_lim_delta. + */ +static void srpt_aborted_task(struct se_cmd *cmd) +{ + struct srpt_send_ioctx *ioctx = container_of(cmd, + struct srpt_send_ioctx, cmd); + struct srpt_rdma_ch *ch = ioctx->ch; + + atomic_inc(&ch->req_lim_delta); +} + +static int srpt_queue_status(struct se_cmd *cmd) +{ + struct srpt_send_ioctx *ioctx; + + ioctx = container_of(cmd, struct srpt_send_ioctx, cmd); + BUG_ON(ioctx->sense_data != cmd->sense_buffer); + if (cmd->se_cmd_flags & + (SCF_TRANSPORT_TASK_SENSE | SCF_EMULATED_TASK_SENSE)) + WARN_ON(cmd->scsi_status != SAM_STAT_CHECK_CONDITION); + ioctx->queue_status_only = true; + srpt_queue_response(cmd); + return 0; +} + +static void srpt_refresh_port_work(struct work_struct *work) +{ + struct srpt_port *sport = container_of(work, struct srpt_port, work); + + srpt_refresh_port(sport); +} + +/** + * srpt_release_sport - disable login and wait for associated channels + * @sport: SRPT HCA port. + */ +static int srpt_release_sport(struct srpt_port *sport) +{ + DECLARE_COMPLETION_ONSTACK(c); + struct srpt_nexus *nexus, *next_n; + struct srpt_rdma_ch *ch; + + WARN_ON_ONCE(irqs_disabled()); + + sport->freed_channels = &c; + + mutex_lock(&sport->mutex); + srpt_set_enabled(sport, false); + mutex_unlock(&sport->mutex); + + while (atomic_read(&sport->refcount) > 0 && + wait_for_completion_timeout(&c, 5 * HZ) <= 0) { + pr_info("%s_%d: waiting for unregistration of %d sessions ...\n", + dev_name(&sport->sdev->device->dev), sport->port, + atomic_read(&sport->refcount)); + rcu_read_lock(); + list_for_each_entry(nexus, &sport->nexus_list, entry) { + list_for_each_entry(ch, &nexus->ch_list, list) { + pr_info("%s-%d: state %s\n", + ch->sess_name, ch->qp->qp_num, + get_ch_state_name(ch->state)); + } + } + rcu_read_unlock(); + } + + mutex_lock(&sport->mutex); + list_for_each_entry_safe(nexus, next_n, &sport->nexus_list, entry) { + list_del(&nexus->entry); + kfree_rcu(nexus, rcu); + } + mutex_unlock(&sport->mutex); + + return 0; +} + +struct port_and_port_id { + struct srpt_port *sport; + struct srpt_port_id **port_id; +}; + +static struct port_and_port_id __srpt_lookup_port(const char *name) +{ + struct ib_device *dev; + struct srpt_device *sdev; + struct srpt_port *sport; + int i; + + list_for_each_entry(sdev, &srpt_dev_list, list) { + dev = sdev->device; + if (!dev) + continue; + + for (i = 0; i < dev->phys_port_cnt; i++) { + sport = &sdev->port[i]; + + if (strcmp(sport->guid_name, name) == 0) { + kref_get(&sdev->refcnt); + return (struct port_and_port_id){ + sport, &sport->guid_id}; + } + if (strcmp(sport->gid_name, name) == 0) { + kref_get(&sdev->refcnt); + return (struct port_and_port_id){ + sport, &sport->gid_id}; + } + } + } + + return (struct port_and_port_id){}; +} + +/** + * srpt_lookup_port() - Look up an RDMA port by name + * @name: ASCII port name + * + * Increments the RDMA port reference count if an RDMA port pointer is returned. + * The caller must drop that reference count by calling srpt_port_put_ref(). + */ +static struct port_and_port_id srpt_lookup_port(const char *name) +{ + struct port_and_port_id papi; + + spin_lock(&srpt_dev_lock); + papi = __srpt_lookup_port(name); + spin_unlock(&srpt_dev_lock); + + return papi; +} + +static void srpt_free_srq(struct srpt_device *sdev) +{ + if (!sdev->srq) + return; + + ib_destroy_srq(sdev->srq); + srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev, + sdev->srq_size, sdev->req_buf_cache, + DMA_FROM_DEVICE); + kmem_cache_destroy(sdev->req_buf_cache); + sdev->srq = NULL; +} + +static int srpt_alloc_srq(struct srpt_device *sdev) +{ + struct ib_srq_init_attr srq_attr = { + .event_handler = srpt_srq_event, + .srq_context = (void *)sdev, + .attr.max_wr = sdev->srq_size, + .attr.max_sge = 1, + .srq_type = IB_SRQT_BASIC, + }; + struct ib_device *device = sdev->device; + struct ib_srq *srq; + int i; + + WARN_ON_ONCE(sdev->srq); + srq = ib_create_srq(sdev->pd, &srq_attr); + if (IS_ERR(srq)) { + pr_debug("ib_create_srq() failed: %ld\n", PTR_ERR(srq)); + return PTR_ERR(srq); + } + + pr_debug("create SRQ #wr= %d max_allow=%d dev= %s\n", sdev->srq_size, + sdev->device->attrs.max_srq_wr, dev_name(&device->dev)); + + sdev->req_buf_cache = kmem_cache_create("srpt-srq-req-buf", + srp_max_req_size, 0, 0, NULL); + if (!sdev->req_buf_cache) + goto free_srq; + + sdev->ioctx_ring = (struct srpt_recv_ioctx **) + srpt_alloc_ioctx_ring(sdev, sdev->srq_size, + sizeof(*sdev->ioctx_ring[0]), + sdev->req_buf_cache, 0, DMA_FROM_DEVICE); + if (!sdev->ioctx_ring) + goto free_cache; + + sdev->use_srq = true; + sdev->srq = srq; + + for (i = 0; i < sdev->srq_size; ++i) { + INIT_LIST_HEAD(&sdev->ioctx_ring[i]->wait_list); + srpt_post_recv(sdev, NULL, sdev->ioctx_ring[i]); + } + + return 0; + +free_cache: + kmem_cache_destroy(sdev->req_buf_cache); + +free_srq: + ib_destroy_srq(srq); + return -ENOMEM; +} + +static int srpt_use_srq(struct srpt_device *sdev, bool use_srq) +{ + struct ib_device *device = sdev->device; + int ret = 0; + + if (!use_srq) { + srpt_free_srq(sdev); + sdev->use_srq = false; + } else if (use_srq && !sdev->srq) { + ret = srpt_alloc_srq(sdev); + } + pr_debug("%s(%s): use_srq = %d; ret = %d\n", __func__, + dev_name(&device->dev), sdev->use_srq, ret); + return ret; +} + +static void srpt_free_sdev(struct kref *refcnt) +{ + struct srpt_device *sdev = container_of(refcnt, typeof(*sdev), refcnt); + + kfree(sdev); +} + +static void srpt_sdev_put(struct srpt_device *sdev) +{ + kref_put(&sdev->refcnt, srpt_free_sdev); +} + +/** + * srpt_add_one - InfiniBand device addition callback function + * @device: Describes a HCA. + */ +static int srpt_add_one(struct ib_device *device) +{ + struct srpt_device *sdev; + struct srpt_port *sport; + int i, ret; + + pr_debug("device = %p\n", device); + + sdev = kzalloc(struct_size(sdev, port, device->phys_port_cnt), + GFP_KERNEL); + if (!sdev) + return -ENOMEM; + + kref_init(&sdev->refcnt); + sdev->device = device; + mutex_init(&sdev->sdev_mutex); + + sdev->pd = ib_alloc_pd(device, 0); + if (IS_ERR(sdev->pd)) { + ret = PTR_ERR(sdev->pd); + goto free_dev; + } + + sdev->lkey = sdev->pd->local_dma_lkey; + + sdev->srq_size = min(srpt_srq_size, sdev->device->attrs.max_srq_wr); + + srpt_use_srq(sdev, sdev->port[0].port_attrib.use_srq); + + if (!srpt_service_guid) + srpt_service_guid = be64_to_cpu(device->node_guid); + + if (rdma_port_get_link_layer(device, 1) == IB_LINK_LAYER_INFINIBAND) + sdev->cm_id = ib_create_cm_id(device, srpt_cm_handler, sdev); + if (IS_ERR(sdev->cm_id)) { + pr_info("ib_create_cm_id() failed: %ld\n", + PTR_ERR(sdev->cm_id)); + ret = PTR_ERR(sdev->cm_id); + sdev->cm_id = NULL; + if (!rdma_cm_id) + goto err_ring; + } + + /* print out target login information */ + pr_debug("Target login info: id_ext=%016llx,ioc_guid=%016llx,pkey=ffff,service_id=%016llx\n", + srpt_service_guid, srpt_service_guid, srpt_service_guid); + + /* + * We do not have a consistent service_id (ie. also id_ext of target_id) + * to identify this target. We currently use the guid of the first HCA + * in the system as service_id; therefore, the target_id will change + * if this HCA is gone bad and replaced by different HCA + */ + ret = sdev->cm_id ? + ib_cm_listen(sdev->cm_id, cpu_to_be64(srpt_service_guid), 0) : + 0; + if (ret < 0) { + pr_err("ib_cm_listen() failed: %d (cm_id state = %d)\n", ret, + sdev->cm_id->state); + goto err_cm; + } + + INIT_IB_EVENT_HANDLER(&sdev->event_handler, sdev->device, + srpt_event_handler); + ib_register_event_handler(&sdev->event_handler); + + for (i = 1; i <= sdev->device->phys_port_cnt; i++) { + sport = &sdev->port[i - 1]; + INIT_LIST_HEAD(&sport->nexus_list); + mutex_init(&sport->mutex); + sport->sdev = sdev; + sport->port = i; + sport->port_attrib.srp_max_rdma_size = DEFAULT_MAX_RDMA_SIZE; + sport->port_attrib.srp_max_rsp_size = DEFAULT_MAX_RSP_SIZE; + sport->port_attrib.srp_sq_size = DEF_SRPT_SQ_SIZE; + sport->port_attrib.use_srq = false; + INIT_WORK(&sport->work, srpt_refresh_port_work); + + ret = srpt_refresh_port(sport); + if (ret) { + pr_err("MAD registration failed for %s-%d.\n", + dev_name(&sdev->device->dev), i); + i--; + goto err_port; + } + } + + spin_lock(&srpt_dev_lock); + list_add_tail(&sdev->list, &srpt_dev_list); + spin_unlock(&srpt_dev_lock); + + ib_set_client_data(device, &srpt_client, sdev); + pr_debug("added %s.\n", dev_name(&device->dev)); + return 0; + +err_port: + srpt_unregister_mad_agent(sdev, i); + ib_unregister_event_handler(&sdev->event_handler); +err_cm: + if (sdev->cm_id) + ib_destroy_cm_id(sdev->cm_id); +err_ring: + srpt_free_srq(sdev); + ib_dealloc_pd(sdev->pd); +free_dev: + srpt_sdev_put(sdev); + pr_info("%s(%s) failed.\n", __func__, dev_name(&device->dev)); + return ret; +} + +/** + * srpt_remove_one - InfiniBand device removal callback function + * @device: Describes a HCA. + * @client_data: The value passed as the third argument to ib_set_client_data(). + */ +static void srpt_remove_one(struct ib_device *device, void *client_data) +{ + struct srpt_device *sdev = client_data; + int i; + + srpt_unregister_mad_agent(sdev, sdev->device->phys_port_cnt); + + ib_unregister_event_handler(&sdev->event_handler); + + /* Cancel any work queued by the just unregistered IB event handler. */ + for (i = 0; i < sdev->device->phys_port_cnt; i++) + cancel_work_sync(&sdev->port[i].work); + + if (sdev->cm_id) + ib_destroy_cm_id(sdev->cm_id); + + ib_set_client_data(device, &srpt_client, NULL); + + /* + * Unregistering a target must happen after destroying sdev->cm_id + * such that no new SRP_LOGIN_REQ information units can arrive while + * destroying the target. + */ + spin_lock(&srpt_dev_lock); + list_del(&sdev->list); + spin_unlock(&srpt_dev_lock); + + for (i = 0; i < sdev->device->phys_port_cnt; i++) + srpt_release_sport(&sdev->port[i]); + + srpt_free_srq(sdev); + + ib_dealloc_pd(sdev->pd); + + srpt_sdev_put(sdev); +} + +static struct ib_client srpt_client = { + .name = DRV_NAME, + .add = srpt_add_one, + .remove = srpt_remove_one +}; + +static int srpt_check_true(struct se_portal_group *se_tpg) +{ + return 1; +} + +static int srpt_check_false(struct se_portal_group *se_tpg) +{ + return 0; +} + +static struct srpt_port *srpt_tpg_to_sport(struct se_portal_group *tpg) +{ + return tpg->se_tpg_wwn->priv; +} + +static struct srpt_port_id *srpt_wwn_to_sport_id(struct se_wwn *wwn) +{ + struct srpt_port *sport = wwn->priv; + + if (sport->guid_id && &sport->guid_id->wwn == wwn) + return sport->guid_id; + if (sport->gid_id && &sport->gid_id->wwn == wwn) + return sport->gid_id; + WARN_ON_ONCE(true); + return NULL; +} + +static char *srpt_get_fabric_wwn(struct se_portal_group *tpg) +{ + struct srpt_tpg *stpg = container_of(tpg, typeof(*stpg), tpg); + + return stpg->sport_id->name; +} + +static u16 srpt_get_tag(struct se_portal_group *tpg) +{ + return 1; +} + +static u32 srpt_tpg_get_inst_index(struct se_portal_group *se_tpg) +{ + return 1; +} + +static void srpt_release_cmd(struct se_cmd *se_cmd) +{ + struct srpt_send_ioctx *ioctx = container_of(se_cmd, + struct srpt_send_ioctx, cmd); + struct srpt_rdma_ch *ch = ioctx->ch; + struct srpt_recv_ioctx *recv_ioctx = ioctx->recv_ioctx; + + WARN_ON_ONCE(ioctx->state != SRPT_STATE_DONE && + !(ioctx->cmd.transport_state & CMD_T_ABORTED)); + + if (recv_ioctx) { + WARN_ON_ONCE(!list_empty(&recv_ioctx->wait_list)); + ioctx->recv_ioctx = NULL; + srpt_post_recv(ch->sport->sdev, ch, recv_ioctx); + } + + if (ioctx->n_rw_ctx) { + srpt_free_rw_ctxs(ch, ioctx); + ioctx->n_rw_ctx = 0; + } + + target_free_tag(se_cmd->se_sess, se_cmd); +} + +/** + * srpt_close_session - forcibly close a session + * @se_sess: SCSI target session. + * + * Callback function invoked by the TCM core to clean up sessions associated + * with a node ACL when the user invokes + * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id + */ +static void srpt_close_session(struct se_session *se_sess) +{ + struct srpt_rdma_ch *ch = se_sess->fabric_sess_ptr; + + srpt_disconnect_ch_sync(ch); +} + +/** + * srpt_sess_get_index - return the value of scsiAttIntrPortIndex (SCSI-MIB) + * @se_sess: SCSI target session. + * + * A quote from RFC 4455 (SCSI-MIB) about this MIB object: + * This object represents an arbitrary integer used to uniquely identify a + * particular attached remote initiator port to a particular SCSI target port + * within a particular SCSI target device within a particular SCSI instance. + */ +static u32 srpt_sess_get_index(struct se_session *se_sess) +{ + return 0; +} + +static void srpt_set_default_node_attrs(struct se_node_acl *nacl) +{ +} + +/* Note: only used from inside debug printk's by the TCM core. */ +static int srpt_get_tcm_cmd_state(struct se_cmd *se_cmd) +{ + struct srpt_send_ioctx *ioctx; + + ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd); + return ioctx->state; +} + +static int srpt_parse_guid(u64 *guid, const char *name) +{ + u16 w[4]; + int ret = -EINVAL; + + if (sscanf(name, "%hx:%hx:%hx:%hx", &w[0], &w[1], &w[2], &w[3]) != 4) + goto out; + *guid = get_unaligned_be64(w); + ret = 0; +out: + return ret; +} + +/** + * srpt_parse_i_port_id - parse an initiator port ID + * @name: ASCII representation of a 128-bit initiator port ID. + * @i_port_id: Binary 128-bit port ID. + */ +static int srpt_parse_i_port_id(u8 i_port_id[16], const char *name) +{ + const char *p; + unsigned len, count, leading_zero_bytes; + int ret; + + p = name; + if (strncasecmp(p, "0x", 2) == 0) + p += 2; + ret = -EINVAL; + len = strlen(p); + if (len % 2) + goto out; + count = min(len / 2, 16U); + leading_zero_bytes = 16 - count; + memset(i_port_id, 0, leading_zero_bytes); + ret = hex2bin(i_port_id + leading_zero_bytes, p, count); + +out: + return ret; +} + +/* + * configfs callback function invoked for mkdir + * /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id + * + * i_port_id must be an initiator port GUID, GID or IP address. See also the + * target_alloc_session() calls in this driver. Examples of valid initiator + * port IDs: + * 0x0000000000000000505400fffe4a0b7b + * 0000000000000000505400fffe4a0b7b + * 5054:00ff:fe4a:0b7b + * 192.168.122.76 + */ +static int srpt_init_nodeacl(struct se_node_acl *se_nacl, const char *name) +{ + struct sockaddr_storage sa; + u64 guid; + u8 i_port_id[16]; + int ret; + + ret = srpt_parse_guid(&guid, name); + if (ret < 0) + ret = srpt_parse_i_port_id(i_port_id, name); + if (ret < 0) + ret = inet_pton_with_scope(&init_net, AF_UNSPEC, name, NULL, + &sa); + if (ret < 0) + pr_err("invalid initiator port ID %s\n", name); + return ret; +} + +static ssize_t srpt_tpg_attrib_srp_max_rdma_size_show(struct config_item *item, + char *page) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + + return sprintf(page, "%u\n", sport->port_attrib.srp_max_rdma_size); +} + +static ssize_t srpt_tpg_attrib_srp_max_rdma_size_store(struct config_item *item, + const char *page, size_t count) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + unsigned long val; + int ret; + + ret = kstrtoul(page, 0, &val); + if (ret < 0) { + pr_err("kstrtoul() failed with ret: %d\n", ret); + return -EINVAL; + } + if (val > MAX_SRPT_RDMA_SIZE) { + pr_err("val: %lu exceeds MAX_SRPT_RDMA_SIZE: %d\n", val, + MAX_SRPT_RDMA_SIZE); + return -EINVAL; + } + if (val < DEFAULT_MAX_RDMA_SIZE) { + pr_err("val: %lu smaller than DEFAULT_MAX_RDMA_SIZE: %d\n", + val, DEFAULT_MAX_RDMA_SIZE); + return -EINVAL; + } + sport->port_attrib.srp_max_rdma_size = val; + + return count; +} + +static ssize_t srpt_tpg_attrib_srp_max_rsp_size_show(struct config_item *item, + char *page) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + + return sprintf(page, "%u\n", sport->port_attrib.srp_max_rsp_size); +} + +static ssize_t srpt_tpg_attrib_srp_max_rsp_size_store(struct config_item *item, + const char *page, size_t count) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + unsigned long val; + int ret; + + ret = kstrtoul(page, 0, &val); + if (ret < 0) { + pr_err("kstrtoul() failed with ret: %d\n", ret); + return -EINVAL; + } + if (val > MAX_SRPT_RSP_SIZE) { + pr_err("val: %lu exceeds MAX_SRPT_RSP_SIZE: %d\n", val, + MAX_SRPT_RSP_SIZE); + return -EINVAL; + } + if (val < MIN_MAX_RSP_SIZE) { + pr_err("val: %lu smaller than MIN_MAX_RSP_SIZE: %d\n", val, + MIN_MAX_RSP_SIZE); + return -EINVAL; + } + sport->port_attrib.srp_max_rsp_size = val; + + return count; +} + +static ssize_t srpt_tpg_attrib_srp_sq_size_show(struct config_item *item, + char *page) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + + return sprintf(page, "%u\n", sport->port_attrib.srp_sq_size); +} + +static ssize_t srpt_tpg_attrib_srp_sq_size_store(struct config_item *item, + const char *page, size_t count) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + unsigned long val; + int ret; + + ret = kstrtoul(page, 0, &val); + if (ret < 0) { + pr_err("kstrtoul() failed with ret: %d\n", ret); + return -EINVAL; + } + if (val > MAX_SRPT_SRQ_SIZE) { + pr_err("val: %lu exceeds MAX_SRPT_SRQ_SIZE: %d\n", val, + MAX_SRPT_SRQ_SIZE); + return -EINVAL; + } + if (val < MIN_SRPT_SRQ_SIZE) { + pr_err("val: %lu smaller than MIN_SRPT_SRQ_SIZE: %d\n", val, + MIN_SRPT_SRQ_SIZE); + return -EINVAL; + } + sport->port_attrib.srp_sq_size = val; + + return count; +} + +static ssize_t srpt_tpg_attrib_use_srq_show(struct config_item *item, + char *page) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + + return sprintf(page, "%d\n", sport->port_attrib.use_srq); +} + +static ssize_t srpt_tpg_attrib_use_srq_store(struct config_item *item, + const char *page, size_t count) +{ + struct se_portal_group *se_tpg = attrib_to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + struct srpt_device *sdev = sport->sdev; + unsigned long val; + bool enabled; + int ret; + + ret = kstrtoul(page, 0, &val); + if (ret < 0) + return ret; + if (val != !!val) + return -EINVAL; + + ret = mutex_lock_interruptible(&sdev->sdev_mutex); + if (ret < 0) + return ret; + ret = mutex_lock_interruptible(&sport->mutex); + if (ret < 0) + goto unlock_sdev; + enabled = sport->enabled; + /* Log out all initiator systems before changing 'use_srq'. */ + srpt_set_enabled(sport, false); + sport->port_attrib.use_srq = val; + srpt_use_srq(sdev, sport->port_attrib.use_srq); + srpt_set_enabled(sport, enabled); + ret = count; + mutex_unlock(&sport->mutex); +unlock_sdev: + mutex_unlock(&sdev->sdev_mutex); + + return ret; +} + +CONFIGFS_ATTR(srpt_tpg_attrib_, srp_max_rdma_size); +CONFIGFS_ATTR(srpt_tpg_attrib_, srp_max_rsp_size); +CONFIGFS_ATTR(srpt_tpg_attrib_, srp_sq_size); +CONFIGFS_ATTR(srpt_tpg_attrib_, use_srq); + +static struct configfs_attribute *srpt_tpg_attrib_attrs[] = { + &srpt_tpg_attrib_attr_srp_max_rdma_size, + &srpt_tpg_attrib_attr_srp_max_rsp_size, + &srpt_tpg_attrib_attr_srp_sq_size, + &srpt_tpg_attrib_attr_use_srq, + NULL, +}; + +static struct rdma_cm_id *srpt_create_rdma_id(struct sockaddr *listen_addr) +{ + struct rdma_cm_id *rdma_cm_id; + int ret; + + rdma_cm_id = rdma_create_id(&init_net, srpt_rdma_cm_handler, + NULL, RDMA_PS_TCP, IB_QPT_RC); + if (IS_ERR(rdma_cm_id)) { + pr_err("RDMA/CM ID creation failed: %ld\n", + PTR_ERR(rdma_cm_id)); + goto out; + } + + ret = rdma_bind_addr(rdma_cm_id, listen_addr); + if (ret) { + char addr_str[64]; + + snprintf(addr_str, sizeof(addr_str), "%pISp", listen_addr); + pr_err("Binding RDMA/CM ID to address %s failed: %d\n", + addr_str, ret); + rdma_destroy_id(rdma_cm_id); + rdma_cm_id = ERR_PTR(ret); + goto out; + } + + ret = rdma_listen(rdma_cm_id, 128); + if (ret) { + pr_err("rdma_listen() failed: %d\n", ret); + rdma_destroy_id(rdma_cm_id); + rdma_cm_id = ERR_PTR(ret); + } + +out: + return rdma_cm_id; +} + +static ssize_t srpt_rdma_cm_port_show(struct config_item *item, char *page) +{ + return sprintf(page, "%d\n", rdma_cm_port); +} + +static ssize_t srpt_rdma_cm_port_store(struct config_item *item, + const char *page, size_t count) +{ + struct sockaddr_in addr4 = { .sin_family = AF_INET }; + struct sockaddr_in6 addr6 = { .sin6_family = AF_INET6 }; + struct rdma_cm_id *new_id = NULL; + u16 val; + int ret; + + ret = kstrtou16(page, 0, &val); + if (ret < 0) + return ret; + ret = count; + if (rdma_cm_port == val) + goto out; + + if (val) { + addr6.sin6_port = cpu_to_be16(val); + new_id = srpt_create_rdma_id((struct sockaddr *)&addr6); + if (IS_ERR(new_id)) { + addr4.sin_port = cpu_to_be16(val); + new_id = srpt_create_rdma_id((struct sockaddr *)&addr4); + if (IS_ERR(new_id)) { + ret = PTR_ERR(new_id); + goto out; + } + } + } + + mutex_lock(&rdma_cm_mutex); + rdma_cm_port = val; + swap(rdma_cm_id, new_id); + mutex_unlock(&rdma_cm_mutex); + + if (new_id) + rdma_destroy_id(new_id); + ret = count; +out: + return ret; +} + +CONFIGFS_ATTR(srpt_, rdma_cm_port); + +static struct configfs_attribute *srpt_da_attrs[] = { + &srpt_attr_rdma_cm_port, + NULL, +}; + +static ssize_t srpt_tpg_enable_show(struct config_item *item, char *page) +{ + struct se_portal_group *se_tpg = to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + + return snprintf(page, PAGE_SIZE, "%d\n", sport->enabled); +} + +static ssize_t srpt_tpg_enable_store(struct config_item *item, + const char *page, size_t count) +{ + struct se_portal_group *se_tpg = to_tpg(item); + struct srpt_port *sport = srpt_tpg_to_sport(se_tpg); + unsigned long tmp; + int ret; + + ret = kstrtoul(page, 0, &tmp); + if (ret < 0) { + pr_err("Unable to extract srpt_tpg_store_enable\n"); + return -EINVAL; + } + + if ((tmp != 0) && (tmp != 1)) { + pr_err("Illegal value for srpt_tpg_store_enable: %lu\n", tmp); + return -EINVAL; + } + + mutex_lock(&sport->mutex); + srpt_set_enabled(sport, tmp); + mutex_unlock(&sport->mutex); + + return count; +} + +CONFIGFS_ATTR(srpt_tpg_, enable); + +static struct configfs_attribute *srpt_tpg_attrs[] = { + &srpt_tpg_attr_enable, + NULL, +}; + +/** + * srpt_make_tpg - configfs callback invoked for mkdir /sys/kernel/config/target/$driver/$port/$tpg + * @wwn: Corresponds to $driver/$port. + * @name: $tpg. + */ +static struct se_portal_group *srpt_make_tpg(struct se_wwn *wwn, + const char *name) +{ + struct srpt_port_id *sport_id = srpt_wwn_to_sport_id(wwn); + struct srpt_tpg *stpg; + int res = -ENOMEM; + + stpg = kzalloc(sizeof(*stpg), GFP_KERNEL); + if (!stpg) + return ERR_PTR(res); + stpg->sport_id = sport_id; + res = core_tpg_register(wwn, &stpg->tpg, SCSI_PROTOCOL_SRP); + if (res) { + kfree(stpg); + return ERR_PTR(res); + } + + mutex_lock(&sport_id->mutex); + list_add_tail(&stpg->entry, &sport_id->tpg_list); + mutex_unlock(&sport_id->mutex); + + return &stpg->tpg; +} + +/** + * srpt_drop_tpg - configfs callback invoked for rmdir /sys/kernel/config/target/$driver/$port/$tpg + * @tpg: Target portal group to deregister. + */ +static void srpt_drop_tpg(struct se_portal_group *tpg) +{ + struct srpt_tpg *stpg = container_of(tpg, typeof(*stpg), tpg); + struct srpt_port_id *sport_id = stpg->sport_id; + struct srpt_port *sport = srpt_tpg_to_sport(tpg); + + mutex_lock(&sport_id->mutex); + list_del(&stpg->entry); + mutex_unlock(&sport_id->mutex); + + sport->enabled = false; + core_tpg_deregister(tpg); + kfree(stpg); +} + +/** + * srpt_make_tport - configfs callback invoked for mkdir /sys/kernel/config/target/$driver/$port + * @tf: Not used. + * @group: Not used. + * @name: $port. + */ +static struct se_wwn *srpt_make_tport(struct target_fabric_configfs *tf, + struct config_group *group, + const char *name) +{ + struct port_and_port_id papi = srpt_lookup_port(name); + struct srpt_port *sport = papi.sport; + struct srpt_port_id *port_id; + + if (!papi.port_id) + return ERR_PTR(-EINVAL); + if (*papi.port_id) { + /* Attempt to create a directory that already exists. */ + WARN_ON_ONCE(true); + return &(*papi.port_id)->wwn; + } + port_id = kzalloc(sizeof(*port_id), GFP_KERNEL); + if (!port_id) { + srpt_sdev_put(sport->sdev); + return ERR_PTR(-ENOMEM); + } + mutex_init(&port_id->mutex); + INIT_LIST_HEAD(&port_id->tpg_list); + port_id->wwn.priv = sport; + memcpy(port_id->name, port_id == sport->guid_id ? sport->guid_name : + sport->gid_name, ARRAY_SIZE(port_id->name)); + + *papi.port_id = port_id; + + return &port_id->wwn; +} + +/** + * srpt_drop_tport - configfs callback invoked for rmdir /sys/kernel/config/target/$driver/$port + * @wwn: $port. + */ +static void srpt_drop_tport(struct se_wwn *wwn) +{ + struct srpt_port_id *port_id = container_of(wwn, typeof(*port_id), wwn); + struct srpt_port *sport = wwn->priv; + + if (sport->guid_id == port_id) + sport->guid_id = NULL; + else if (sport->gid_id == port_id) + sport->gid_id = NULL; + else + WARN_ON_ONCE(true); + + srpt_sdev_put(sport->sdev); + kfree(port_id); +} + +static ssize_t srpt_wwn_version_show(struct config_item *item, char *buf) +{ + return scnprintf(buf, PAGE_SIZE, "\n"); +} + +CONFIGFS_ATTR_RO(srpt_wwn_, version); + +static struct configfs_attribute *srpt_wwn_attrs[] = { + &srpt_wwn_attr_version, + NULL, +}; + +static const struct target_core_fabric_ops srpt_template = { + .module = THIS_MODULE, + .fabric_name = "srpt", + .tpg_get_wwn = srpt_get_fabric_wwn, + .tpg_get_tag = srpt_get_tag, + .tpg_check_demo_mode = srpt_check_false, + .tpg_check_demo_mode_cache = srpt_check_true, + .tpg_check_demo_mode_write_protect = srpt_check_true, + .tpg_check_prod_mode_write_protect = srpt_check_false, + .tpg_get_inst_index = srpt_tpg_get_inst_index, + .release_cmd = srpt_release_cmd, + .check_stop_free = srpt_check_stop_free, + .close_session = srpt_close_session, + .sess_get_index = srpt_sess_get_index, + .sess_get_initiator_sid = NULL, + .write_pending = srpt_write_pending, + .set_default_node_attributes = srpt_set_default_node_attrs, + .get_cmd_state = srpt_get_tcm_cmd_state, + .queue_data_in = srpt_queue_data_in, + .queue_status = srpt_queue_status, + .queue_tm_rsp = srpt_queue_tm_rsp, + .aborted_task = srpt_aborted_task, + /* + * Setup function pointers for generic logic in + * target_core_fabric_configfs.c + */ + .fabric_make_wwn = srpt_make_tport, + .fabric_drop_wwn = srpt_drop_tport, + .fabric_make_tpg = srpt_make_tpg, + .fabric_drop_tpg = srpt_drop_tpg, + .fabric_init_nodeacl = srpt_init_nodeacl, + + .tfc_discovery_attrs = srpt_da_attrs, + .tfc_wwn_attrs = srpt_wwn_attrs, + .tfc_tpg_base_attrs = srpt_tpg_attrs, + .tfc_tpg_attrib_attrs = srpt_tpg_attrib_attrs, +}; + +/** + * srpt_init_module - kernel module initialization + * + * Note: Since ib_register_client() registers callback functions, and since at + * least one of these callback functions (srpt_add_one()) calls target core + * functions, this driver must be registered with the target core before + * ib_register_client() is called. + */ +static int __init srpt_init_module(void) +{ + int ret; + + ret = -EINVAL; + if (srp_max_req_size < MIN_MAX_REQ_SIZE) { + pr_err("invalid value %d for kernel module parameter srp_max_req_size -- must be at least %d.\n", + srp_max_req_size, MIN_MAX_REQ_SIZE); + goto out; + } + + if (srpt_srq_size < MIN_SRPT_SRQ_SIZE + || srpt_srq_size > MAX_SRPT_SRQ_SIZE) { + pr_err("invalid value %d for kernel module parameter srpt_srq_size -- must be in the range [%d..%d].\n", + srpt_srq_size, MIN_SRPT_SRQ_SIZE, MAX_SRPT_SRQ_SIZE); + goto out; + } + + ret = target_register_template(&srpt_template); + if (ret) + goto out; + + ret = ib_register_client(&srpt_client); + if (ret) { + pr_err("couldn't register IB client\n"); + goto out_unregister_target; + } + + return 0; + +out_unregister_target: + target_unregister_template(&srpt_template); +out: + return ret; +} + +static void __exit srpt_cleanup_module(void) +{ + if (rdma_cm_id) + rdma_destroy_id(rdma_cm_id); + ib_unregister_client(&srpt_client); + target_unregister_template(&srpt_template); +} + +module_init(srpt_init_module); +module_exit(srpt_cleanup_module); diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.h b/drivers/infiniband/ulp/srpt/ib_srpt.h new file mode 100644 index 000000000..2bf381ecd --- /dev/null +++ b/drivers/infiniband/ulp/srpt/ib_srpt.h @@ -0,0 +1,469 @@ +/* + * Copyright (c) 2006 - 2009 Mellanox Technology Inc. All rights reserved. + * Copyright (C) 2009 - 2010 Bart Van Assche <bvanassche@acm.org>. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ + +#ifndef IB_SRPT_H +#define IB_SRPT_H + +#include <linux/types.h> +#include <linux/list.h> +#include <linux/wait.h> + +#include <rdma/ib_verbs.h> +#include <rdma/ib_sa.h> +#include <rdma/ib_cm.h> +#include <rdma/rdma_cm.h> +#include <rdma/rw.h> + +#include <scsi/srp.h> + +#include "ib_dm_mad.h" + +/* + * The prefix the ServiceName field must start with in the device management + * ServiceEntries attribute pair. See also the SRP specification. + */ +#define SRP_SERVICE_NAME_PREFIX "SRP.T10:" + +struct srpt_nexus; + +enum { + /* + * SRP IOControllerProfile attributes for SRP target ports that have + * not been defined in <scsi/srp.h>. Source: section B.7, table B.7 + * in the SRP specification. + */ + SRP_PROTOCOL = 0x0108, + SRP_PROTOCOL_VERSION = 0x0001, + SRP_IO_SUBCLASS = 0x609e, + SRP_SEND_TO_IOC = 0x01, + SRP_SEND_FROM_IOC = 0x02, + SRP_RDMA_READ_FROM_IOC = 0x08, + SRP_RDMA_WRITE_FROM_IOC = 0x20, + + /* + * srp_login_cmd.req_flags bitmasks. See also table 9 in the SRP + * specification. + */ + SRP_MTCH_ACTION = 0x03, /* MULTI-CHANNEL ACTION */ + SRP_LOSOLNT = 0x10, /* logout solicited notification */ + SRP_CRSOLNT = 0x20, /* credit request solicited notification */ + SRP_AESOLNT = 0x40, /* asynchronous event solicited notification */ + + /* + * srp_cmd.sol_nt / srp_tsk_mgmt.sol_not bitmasks. See also tables + * 18 and 20 in the SRP specification. + */ + SRP_SCSOLNT = 0x02, /* SCSOLNT = successful solicited notification */ + SRP_UCSOLNT = 0x04, /* UCSOLNT = unsuccessful solicited notification */ + + /* + * srp_rsp.sol_not / srp_t_logout.sol_not bitmasks. See also tables + * 16 and 22 in the SRP specification. + */ + SRP_SOLNT = 0x01, /* SOLNT = solicited notification */ + + /* See also table 24 in the SRP specification. */ + SRP_TSK_MGMT_SUCCESS = 0x00, + SRP_TSK_MGMT_FUNC_NOT_SUPP = 0x04, + SRP_TSK_MGMT_FAILED = 0x05, + + /* See also table 21 in the SRP specification. */ + SRP_CMD_SIMPLE_Q = 0x0, + SRP_CMD_HEAD_OF_Q = 0x1, + SRP_CMD_ORDERED_Q = 0x2, + SRP_CMD_ACA = 0x4, + + SRPT_DEF_SG_TABLESIZE = 128, + + MIN_SRPT_SQ_SIZE = 16, + DEF_SRPT_SQ_SIZE = 4096, + MAX_SRPT_RQ_SIZE = 128, + MIN_SRPT_SRQ_SIZE = 4, + DEFAULT_SRPT_SRQ_SIZE = 4095, + MAX_SRPT_SRQ_SIZE = 65535, + MAX_SRPT_RDMA_SIZE = 1U << 24, + MAX_SRPT_RSP_SIZE = 1024, + + SRP_MAX_ADD_CDB_LEN = 16, + SRP_MAX_IMM_DATA_OFFSET = 80, + SRP_MAX_IMM_DATA = 8 * 1024, + MIN_MAX_REQ_SIZE = 996, + DEFAULT_MAX_REQ_SIZE_1 = sizeof(struct srp_cmd)/*48*/ + + SRP_MAX_ADD_CDB_LEN + + sizeof(struct srp_indirect_buf)/*20*/ + + 128 * sizeof(struct srp_direct_buf)/*16*/, + DEFAULT_MAX_REQ_SIZE_2 = SRP_MAX_IMM_DATA_OFFSET + + sizeof(struct srp_imm_buf) + SRP_MAX_IMM_DATA, + DEFAULT_MAX_REQ_SIZE = DEFAULT_MAX_REQ_SIZE_1 > DEFAULT_MAX_REQ_SIZE_2 ? + DEFAULT_MAX_REQ_SIZE_1 : DEFAULT_MAX_REQ_SIZE_2, + + MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4, + DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */ + + DEFAULT_MAX_RDMA_SIZE = 65536, +}; + +/** + * enum srpt_command_state - SCSI command state managed by SRPT + * @SRPT_STATE_NEW: New command arrived and is being processed. + * @SRPT_STATE_NEED_DATA: Processing a write or bidir command and waiting + * for data arrival. + * @SRPT_STATE_DATA_IN: Data for the write or bidir command arrived and is + * being processed. + * @SRPT_STATE_CMD_RSP_SENT: SRP_RSP for SRP_CMD has been sent. + * @SRPT_STATE_MGMT: Processing a SCSI task management command. + * @SRPT_STATE_MGMT_RSP_SENT: SRP_RSP for SRP_TSK_MGMT has been sent. + * @SRPT_STATE_DONE: Command processing finished successfully, command + * processing has been aborted or command processing + * failed. + */ +enum srpt_command_state { + SRPT_STATE_NEW = 0, + SRPT_STATE_NEED_DATA = 1, + SRPT_STATE_DATA_IN = 2, + SRPT_STATE_CMD_RSP_SENT = 3, + SRPT_STATE_MGMT = 4, + SRPT_STATE_MGMT_RSP_SENT = 5, + SRPT_STATE_DONE = 6, +}; + +/** + * struct srpt_ioctx - shared SRPT I/O context information + * @cqe: Completion queue element. + * @buf: Pointer to the buffer. + * @dma: DMA address of the buffer. + * @offset: Offset of the first byte in @buf and @dma that is actually used. + * @index: Index of the I/O context in its ioctx_ring array. + */ +struct srpt_ioctx { + struct ib_cqe cqe; + void *buf; + dma_addr_t dma; + uint32_t offset; + uint32_t index; +}; + +/** + * struct srpt_recv_ioctx - SRPT receive I/O context + * @ioctx: See above. + * @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list. + * @byte_len: Number of bytes in @ioctx.buf. + */ +struct srpt_recv_ioctx { + struct srpt_ioctx ioctx; + struct list_head wait_list; + int byte_len; +}; + +struct srpt_rw_ctx { + struct rdma_rw_ctx rw; + struct scatterlist *sg; + unsigned int nents; +}; + +/** + * struct srpt_send_ioctx - SRPT send I/O context + * @ioctx: See above. + * @ch: Channel pointer. + * @recv_ioctx: Receive I/O context associated with this send I/O context. + * Only used for processing immediate data. + * @s_rw_ctx: @rw_ctxs points here if only a single rw_ctx is needed. + * @rw_ctxs: RDMA read/write contexts. + * @imm_sg: Scatterlist for immediate data. + * @rdma_cqe: RDMA completion queue element. + * @state: I/O context state. + * @cmd: Target core command data structure. + * @sense_data: SCSI sense data. + * @n_rdma: Number of work requests needed to transfer this ioctx. + * @n_rw_ctx: Size of rw_ctxs array. + * @queue_status_only: Send a SCSI status back to the initiator but no data. + * @sense_data: Sense data to be sent to the initiator. + */ +struct srpt_send_ioctx { + struct srpt_ioctx ioctx; + struct srpt_rdma_ch *ch; + struct srpt_recv_ioctx *recv_ioctx; + + struct srpt_rw_ctx s_rw_ctx; + struct srpt_rw_ctx *rw_ctxs; + + struct scatterlist imm_sg; + + struct ib_cqe rdma_cqe; + enum srpt_command_state state; + struct se_cmd cmd; + u8 n_rdma; + u8 n_rw_ctx; + bool queue_status_only; + u8 sense_data[TRANSPORT_SENSE_BUFFER]; +}; + +/** + * enum rdma_ch_state - SRP channel state + * @CH_CONNECTING: QP is in RTR state; waiting for RTU. + * @CH_LIVE: QP is in RTS state. + * @CH_DISCONNECTING: DREQ has been sent and waiting for DREP or DREQ has + * been received. + * @CH_DRAINING: DREP has been received or waiting for DREP timed out + * and last work request has been queued. + * @CH_DISCONNECTED: Last completion has been received. + */ +enum rdma_ch_state { + CH_CONNECTING, + CH_LIVE, + CH_DISCONNECTING, + CH_DRAINING, + CH_DISCONNECTED, +}; + +/** + * struct srpt_rdma_ch - RDMA channel + * @nexus: I_T nexus this channel is associated with. + * @qp: IB queue pair used for communicating over this channel. + * @ib_cm: See below. + * @ib_cm.cm_id: IB CM ID associated with the channel. + * @rdma_cm: See below. + * @rdma_cm.cm_id: RDMA CM ID associated with the channel. + * @cq: IB completion queue for this channel. + * @cq_size: Number of CQEs in @cq. + * @zw_cqe: Zero-length write CQE. + * @rcu: RCU head. + * @kref: kref for this channel. + * @closed: Completion object that will be signaled as soon as a new + * channel object with the same identity can be created. + * @rq_size: IB receive queue size. + * @max_rsp_size: Maximum size of an RSP response message in bytes. + * @sq_wr_avail: number of work requests available in the send queue. + * @sport: pointer to the information of the HCA port used by this + * channel. + * @max_ti_iu_len: maximum target-to-initiator information unit length. + * @req_lim: request limit: maximum number of requests that may be sent + * by the initiator without having received a response. + * @req_lim_delta: Number of credits not yet sent back to the initiator. + * @imm_data_offset: Offset from start of SRP_CMD for immediate data. + * @spinlock: Protects free_list and state. + * @state: channel state. See also enum rdma_ch_state. + * @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel. + * @processing_wait_list: Whether or not cmd_wait_list is being processed. + * @rsp_buf_cache: kmem_cache for @ioctx_ring. + * @ioctx_ring: Send ring. + * @req_buf_cache: kmem_cache for @ioctx_recv_ring. + * @ioctx_recv_ring: Receive I/O context ring. + * @list: Node in srpt_nexus.ch_list. + * @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This + * list contains struct srpt_ioctx elements and is protected + * against concurrent modification by the cm_id spinlock. + * @pkey: P_Key of the IB partition for this SRP channel. + * @sess: Session information associated with this SRP channel. + * @sess_name: Session name. + * @release_work: Allows scheduling of srpt_release_channel(). + */ +struct srpt_rdma_ch { + struct srpt_nexus *nexus; + struct ib_qp *qp; + union { + struct { + struct ib_cm_id *cm_id; + } ib_cm; + struct { + struct rdma_cm_id *cm_id; + } rdma_cm; + }; + struct ib_cq *cq; + u32 cq_size; + struct ib_cqe zw_cqe; + struct rcu_head rcu; + struct kref kref; + struct completion *closed; + int rq_size; + u32 max_rsp_size; + atomic_t sq_wr_avail; + struct srpt_port *sport; + int max_ti_iu_len; + atomic_t req_lim; + atomic_t req_lim_delta; + u16 imm_data_offset; + spinlock_t spinlock; + enum rdma_ch_state state; + struct kmem_cache *rsp_buf_cache; + struct srpt_send_ioctx **ioctx_ring; + struct kmem_cache *req_buf_cache; + struct srpt_recv_ioctx **ioctx_recv_ring; + struct list_head list; + struct list_head cmd_wait_list; + uint16_t pkey; + bool using_rdma_cm; + bool processing_wait_list; + struct se_session *sess; + u8 sess_name[40]; + struct work_struct release_work; +}; + +/** + * struct srpt_nexus - I_T nexus + * @rcu: RCU head for this data structure. + * @entry: srpt_port.nexus_list list node. + * @ch_list: struct srpt_rdma_ch list. Protected by srpt_port.mutex. + * @i_port_id: 128-bit initiator port identifier copied from SRP_LOGIN_REQ. + * @t_port_id: 128-bit target port identifier copied from SRP_LOGIN_REQ. + */ +struct srpt_nexus { + struct rcu_head rcu; + struct list_head entry; + struct list_head ch_list; + u8 i_port_id[16]; + u8 t_port_id[16]; +}; + +/** + * struct srpt_port_attib - attributes for SRPT port + * @srp_max_rdma_size: Maximum size of SRP RDMA transfers for new connections. + * @srp_max_rsp_size: Maximum size of SRP response messages in bytes. + * @srp_sq_size: Shared receive queue (SRQ) size. + * @use_srq: Whether or not to use SRQ. + */ +struct srpt_port_attrib { + u32 srp_max_rdma_size; + u32 srp_max_rsp_size; + u32 srp_sq_size; + bool use_srq; +}; + +/** + * struct srpt_tpg - information about a single "target portal group" + * @entry: Entry in @sport_id->tpg_list. + * @sport_id: Port name this TPG is associated with. + * @tpg: LIO TPG data structure. + * + * Zero or more target portal groups are associated with each port name + * (srpt_port_id). With each TPG an ACL list is associated. + */ +struct srpt_tpg { + struct list_head entry; + struct srpt_port_id *sport_id; + struct se_portal_group tpg; +}; + +/** + * struct srpt_port_id - LIO RDMA port information + * @mutex: Protects @tpg_list changes. + * @tpg_list: TPGs associated with the RDMA port name. + * @wwn: WWN associated with the RDMA port name. + * @name: ASCII representation of the port name. + * + * Multiple sysfs directories can be associated with a single RDMA port. This + * data structure represents a single (port, name) pair. + */ +struct srpt_port_id { + struct mutex mutex; + struct list_head tpg_list; + struct se_wwn wwn; + char name[64]; +}; + +/** + * struct srpt_port - SRPT RDMA port information + * @sdev: backpointer to the HCA information. + * @mad_agent: per-port management datagram processing information. + * @enabled: Whether or not this target port is enabled. + * @port: one-based port number. + * @sm_lid: cached value of the port's sm_lid. + * @lid: cached value of the port's lid. + * @gid: cached value of the port's gid. + * @work: work structure for refreshing the aforementioned cached values. + * @guid_name: port name in GUID format. + * @guid_id: LIO target port information for the port name in GUID format. + * @gid_name: port name in GID format. + * @gid_id: LIO target port information for the port name in GID format. + * @port_attrib: Port attributes that can be accessed through configfs. + * @refcount: Number of objects associated with this port. + * @freed_channels: Completion that will be signaled once @refcount becomes 0. + * @mutex: Protects nexus_list. + * @nexus_list: Nexus list. See also srpt_nexus.entry. + */ +struct srpt_port { + struct srpt_device *sdev; + struct ib_mad_agent *mad_agent; + bool enabled; + u8 port; + u32 sm_lid; + u32 lid; + union ib_gid gid; + struct work_struct work; + char guid_name[64]; + struct srpt_port_id *guid_id; + char gid_name[64]; + struct srpt_port_id *gid_id; + struct srpt_port_attrib port_attrib; + atomic_t refcount; + struct completion *freed_channels; + struct mutex mutex; + struct list_head nexus_list; +}; + +/** + * struct srpt_device - information associated by SRPT with a single HCA + * @refcnt: Reference count for this device. + * @device: Backpointer to the struct ib_device managed by the IB core. + * @pd: IB protection domain. + * @lkey: L_Key (local key) with write access to all local memory. + * @srq: Per-HCA SRQ (shared receive queue). + * @cm_id: Connection identifier. + * @srq_size: SRQ size. + * @sdev_mutex: Serializes use_srq changes. + * @use_srq: Whether or not to use SRQ. + * @req_buf_cache: kmem_cache for @ioctx_ring buffers. + * @ioctx_ring: Per-HCA SRQ. + * @event_handler: Per-HCA asynchronous IB event handler. + * @list: Node in srpt_dev_list. + * @port: Information about the ports owned by this HCA. + */ +struct srpt_device { + struct kref refcnt; + struct ib_device *device; + struct ib_pd *pd; + u32 lkey; + struct ib_srq *srq; + struct ib_cm_id *cm_id; + int srq_size; + struct mutex sdev_mutex; + bool use_srq; + struct kmem_cache *req_buf_cache; + struct srpt_recv_ioctx **ioctx_ring; + struct ib_event_handler event_handler; + struct list_head list; + struct srpt_port port[]; +}; + +#endif /* IB_SRPT_H */ |