diff options
Diffstat (limited to 'kernel/drivers/infiniband/ulp/srpt/ib_srpt.c')
| -rw-r--r-- | kernel/drivers/infiniband/ulp/srpt/ib_srpt.c | 4022 |
1 files changed, 4022 insertions, 0 deletions
diff --git a/kernel/drivers/infiniband/ulp/srpt/ib_srpt.c b/kernel/drivers/infiniband/ulp/srpt/ib_srpt.c new file mode 100644 index 000000000..9b84b4c0a --- /dev/null +++ b/kernel/drivers/infiniband/ulp/srpt/ib_srpt.c @@ -0,0 +1,4022 @@ +/* + * 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 <scsi/scsi_tcq.h> +#include <target/configfs_macros.h> +#include <target/target_core_base.h> +#include <target/target_core_fabric_configfs.h> +#include <target/target_core_fabric.h> +#include <target/target_core_configfs.h> +#include "ib_srpt.h" + +/* Name of this kernel module. */ +#define DRV_NAME "ib_srpt" +#define DRV_VERSION "2.0.0" +#define DRV_RELDATE "2011-02-14" + +#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("InfiniBand SCSI RDMA Protocol target " + "v" DRV_VERSION " (" DRV_RELDATE ")"); +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, struct kernel_param *kp) +{ + return sprintf(buffer, "0x%016llx", *(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; +static const struct target_core_fabric_ops srpt_template; +static void srpt_release_channel(struct srpt_rdma_ch *ch); +static int srpt_queue_status(struct se_cmd *cmd); + +/** + * opposite_dma_dir() - Swap DMA_TO_DEVICE and DMA_FROM_DEVICE. + */ +static inline +enum dma_data_direction opposite_dma_dir(enum dma_data_direction dir) +{ + switch (dir) { + case DMA_TO_DEVICE: return DMA_FROM_DEVICE; + case DMA_FROM_DEVICE: return DMA_TO_DEVICE; + default: return dir; + } +} + +/** + * srpt_sdev_name() - Return the name associated with the HCA. + * + * Examples are ib0, ib1, ... + */ +static inline const char *srpt_sdev_name(struct srpt_device *sdev) +{ + return sdev->device->name; +} + +static enum rdma_ch_state srpt_get_ch_state(struct srpt_rdma_ch *ch) +{ + unsigned long flags; + enum rdma_ch_state state; + + spin_lock_irqsave(&ch->spinlock, flags); + state = ch->state; + spin_unlock_irqrestore(&ch->spinlock, flags); + return state; +} + +static enum rdma_ch_state +srpt_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state new_state) +{ + unsigned long flags; + enum rdma_ch_state prev; + + spin_lock_irqsave(&ch->spinlock, flags); + prev = ch->state; + ch->state = new_state; + spin_unlock_irqrestore(&ch->spinlock, flags); + return prev; +} + +/** + * srpt_test_and_set_ch_state() - Test and set the channel state. + * + * Returns true if and only if the channel state has been set to the new state. + */ +static bool +srpt_test_and_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state old, + enum rdma_ch_state new) +{ + unsigned long flags; + enum rdma_ch_state prev; + + spin_lock_irqsave(&ch->spinlock, flags); + prev = ch->state; + if (prev == old) + ch->state = new; + spin_unlock_irqrestore(&ch->spinlock, flags); + return prev == old; +} + +/** + * srpt_event_handler() - Asynchronous IB event callback function. + * + * 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; + struct srpt_port *sport; + + sdev = ib_get_client_data(event->device, &srpt_client); + if (!sdev || sdev->device != event->device) + return; + + pr_debug("ASYNC event= %d on device= %s\n", event->event, + srpt_sdev_name(sdev)); + + switch (event->event) { + case IB_EVENT_PORT_ERR: + if (event->element.port_num <= sdev->device->phys_port_cnt) { + sport = &sdev->port[event->element.port_num - 1]; + sport->lid = 0; + sport->sm_lid = 0; + } + 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. */ + if (event->element.port_num <= sdev->device->phys_port_cnt) { + sport = &sdev->port[event->element.port_num - 1]; + if (!sport->lid && !sport->sm_lid) + schedule_work(&sport->work); + } + break; + default: + pr_err("received unrecognized IB event %d\n", + event->event); + break; + } +} + +/** + * srpt_srq_event() - SRQ event callback function. + */ +static void srpt_srq_event(struct ib_event *event, void *ctx) +{ + pr_info("SRQ event %d\n", event->event); +} + +/** + * srpt_qp_event() - QP event callback function. + */ +static void srpt_qp_event(struct ib_event *event, struct srpt_rdma_ch *ch) +{ + pr_debug("QP event %d on cm_id=%p sess_name=%s state=%d\n", + event->event, ch->cm_id, ch->sess_name, srpt_get_ch_state(ch)); + + switch (event->event) { + case IB_EVENT_COMM_EST: + ib_cm_notify(ch->cm_id, event->event); + break; + case IB_EVENT_QP_LAST_WQE_REACHED: + if (srpt_test_and_set_ch_state(ch, CH_DRAINING, + CH_RELEASING)) + srpt_release_channel(ch); + else + pr_debug("%s: state %d - ignored LAST_WQE.\n", + ch->sess_name, srpt_get_ch_state(ch)); + break; + default: + pr_err("received unrecognized IB QP event %d\n", event->event); + break; + } +} + +/** + * srpt_set_ioc() - Helper function for initializing an IOUnitInfo structure. + * + * @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. + * + * 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; + cif->resp_time_value = 20; + + mad->mad_hdr.status = 0; +} + +/** + * srpt_get_iou() - Write IOUnitInfo to a management datagram. + * + * 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 = __constant_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. + * + * 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; + + iocp = (struct ib_dm_ioc_profile *)mad->data; + + if (!slot || slot > 16) { + mad->mad_hdr.status + = __constant_cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD); + return; + } + + if (slot > 2) { + mad->mad_hdr.status + = __constant_cpu_to_be16(DM_MAD_STATUS_NO_IOC); + return; + } + + 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->dev_attr.vendor_id); + iocp->device_id = cpu_to_be32(sdev->dev_attr.vendor_part_id); + iocp->device_version = cpu_to_be16(sdev->dev_attr.hw_ver); + iocp->subsys_vendor_id = cpu_to_be32(sdev->dev_attr.vendor_id); + iocp->subsys_device_id = 0x0; + iocp->io_class = __constant_cpu_to_be16(SRP_REV16A_IB_IO_CLASS); + iocp->io_subclass = __constant_cpu_to_be16(SRP_IO_SUBCLASS); + iocp->protocol = __constant_cpu_to_be16(SRP_PROTOCOL); + iocp->protocol_version = __constant_cpu_to_be16(SRP_PROTOCOL_VERSION); + iocp->send_queue_depth = cpu_to_be16(sdev->srq_size); + 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. + * + * 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 + = __constant_cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD); + return; + } + + if (slot > 2 || lo > hi || hi > 1) { + mad->mad_hdr.status + = __constant_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: source 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 = + __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR); + break; + } +} + +/** + * srpt_mad_send_handler() - Post MAD-send callback function. + */ +static void srpt_mad_send_handler(struct ib_mad_agent *mad_agent, + struct ib_mad_send_wc *mad_wc) +{ + ib_destroy_ah(mad_wc->send_buf->ah); + ib_free_send_mad(mad_wc->send_buf); +} + +/** + * srpt_mad_recv_handler() - MAD reception callback function. + */ +static void srpt_mad_recv_handler(struct ib_mad_agent *mad_agent, + 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); + 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 = + __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR); + break; + default: + dm_mad->mad_hdr.status = + __constant_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: + ib_destroy_ah(ah); +err: + ib_free_recv_mad(mad_wc); +} + +/** + * srpt_refresh_port() - Configure a 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_reg_req reg_req; + struct ib_port_modify port_modify; + struct ib_port_attr port_attr; + int ret; + + 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) + goto err_mod_port; + + ret = ib_query_port(sport->sdev->device, sport->port, &port_attr); + if (ret) + goto err_query_port; + + sport->sm_lid = port_attr.sm_lid; + sport->lid = port_attr.lid; + + ret = ib_query_gid(sport->sdev->device, sport->port, 0, &sport->gid); + if (ret) + goto err_query_port; + + 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); + + sport->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(sport->mad_agent)) { + ret = PTR_ERR(sport->mad_agent); + sport->mad_agent = NULL; + goto err_query_port; + } + } + + return 0; + +err_query_port: + + port_modify.set_port_cap_mask = 0; + port_modify.clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP; + ib_modify_port(sport->sdev->device, sport->port, 0, &port_modify); + +err_mod_port: + + return ret; +} + +/** + * srpt_unregister_mad_agent() - Unregister MAD callback functions. + * + * 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) +{ + 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 <= sdev->device->phys_port_cnt; i++) { + sport = &sdev->port[i - 1]; + WARN_ON(sport->port != i); + if (ib_modify_port(sdev->device, i, 0, &port_modify) < 0) + pr_err("disabling MAD processing failed.\n"); + if (sport->mad_agent) { + ib_unregister_mad_agent(sport->mad_agent); + sport->mad_agent = NULL; + } + } +} + +/** + * srpt_alloc_ioctx() - Allocate an SRPT I/O context structure. + */ +static struct srpt_ioctx *srpt_alloc_ioctx(struct srpt_device *sdev, + int ioctx_size, int dma_size, + enum dma_data_direction dir) +{ + struct srpt_ioctx *ioctx; + + ioctx = kmalloc(ioctx_size, GFP_KERNEL); + if (!ioctx) + goto err; + + ioctx->buf = kmalloc(dma_size, GFP_KERNEL); + if (!ioctx->buf) + goto err_free_ioctx; + + ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf, dma_size, dir); + if (ib_dma_mapping_error(sdev->device, ioctx->dma)) + goto err_free_buf; + + return ioctx; + +err_free_buf: + kfree(ioctx->buf); +err_free_ioctx: + kfree(ioctx); +err: + return NULL; +} + +/** + * srpt_free_ioctx() - Free an SRPT I/O context structure. + */ +static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx, + int dma_size, enum dma_data_direction dir) +{ + if (!ioctx) + return; + + ib_dma_unmap_single(sdev->device, ioctx->dma, dma_size, dir); + kfree(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. + * @dma_size: DMA buffer size. + * @dir: DMA data direction. + */ +static struct srpt_ioctx **srpt_alloc_ioctx_ring(struct srpt_device *sdev, + int ring_size, int ioctx_size, + int dma_size, 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 = kmalloc(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, dma_size, dir); + if (!ring[i]) + goto err; + ring[i]->index = i; + } + goto out; + +err: + while (--i >= 0) + srpt_free_ioctx(sdev, ring[i], dma_size, dir); + kfree(ring); + ring = NULL; +out: + return ring; +} + +/** + * srpt_free_ioctx_ring() - Free the ring of SRPT I/O context structures. + */ +static void srpt_free_ioctx_ring(struct srpt_ioctx **ioctx_ring, + struct srpt_device *sdev, int ring_size, + int dma_size, enum dma_data_direction dir) +{ + int i; + + for (i = 0; i < ring_size; ++i) + srpt_free_ioctx(sdev, ioctx_ring[i], dma_size, dir); + kfree(ioctx_ring); +} + +/** + * srpt_get_cmd_state() - Get the state of a SCSI command. + */ +static enum srpt_command_state srpt_get_cmd_state(struct srpt_send_ioctx *ioctx) +{ + enum srpt_command_state state; + unsigned long flags; + + BUG_ON(!ioctx); + + spin_lock_irqsave(&ioctx->spinlock, flags); + state = ioctx->state; + spin_unlock_irqrestore(&ioctx->spinlock, flags); + return state; +} + +/** + * srpt_set_cmd_state() - Set the state of a SCSI command. + * + * 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; + unsigned long flags; + + BUG_ON(!ioctx); + + spin_lock_irqsave(&ioctx->spinlock, flags); + previous = ioctx->state; + if (previous != SRPT_STATE_DONE) + ioctx->state = new; + spin_unlock_irqrestore(&ioctx->spinlock, flags); + + return previous; +} + +/** + * srpt_test_and_set_cmd_state() - Test and set the state of a command. + * + * 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; + unsigned long flags; + + WARN_ON(!ioctx); + WARN_ON(old == SRPT_STATE_DONE); + WARN_ON(new == SRPT_STATE_NEW); + + spin_lock_irqsave(&ioctx->spinlock, flags); + previous = ioctx->state; + if (previous == old) + ioctx->state = new; + spin_unlock_irqrestore(&ioctx->spinlock, flags); + return previous == old; +} + +/** + * srpt_post_recv() - Post an IB receive request. + */ +static int srpt_post_recv(struct srpt_device *sdev, + struct srpt_recv_ioctx *ioctx) +{ + struct ib_sge list; + struct ib_recv_wr wr, *bad_wr; + + BUG_ON(!sdev); + wr.wr_id = encode_wr_id(SRPT_RECV, ioctx->ioctx.index); + + list.addr = ioctx->ioctx.dma; + list.length = srp_max_req_size; + list.lkey = sdev->mr->lkey; + + wr.next = NULL; + wr.sg_list = &list; + wr.num_sge = 1; + + return ib_post_srq_recv(sdev->srq, &wr, &bad_wr); +} + +/** + * srpt_post_send() - Post an IB send request. + * + * Returns zero upon success and a non-zero value upon failure. + */ +static int srpt_post_send(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx, int len) +{ + struct ib_sge list; + struct ib_send_wr wr, *bad_wr; + struct srpt_device *sdev = ch->sport->sdev; + int ret; + + atomic_inc(&ch->req_lim); + + ret = -ENOMEM; + if (unlikely(atomic_dec_return(&ch->sq_wr_avail) < 0)) { + pr_warn("IB send queue full (needed 1)\n"); + goto out; + } + + ib_dma_sync_single_for_device(sdev->device, ioctx->ioctx.dma, len, + DMA_TO_DEVICE); + + list.addr = ioctx->ioctx.dma; + list.length = len; + list.lkey = sdev->mr->lkey; + + wr.next = NULL; + wr.wr_id = encode_wr_id(SRPT_SEND, ioctx->ioctx.index); + wr.sg_list = &list; + wr.num_sge = 1; + wr.opcode = IB_WR_SEND; + wr.send_flags = IB_SEND_SIGNALED; + + ret = ib_post_send(ch->qp, &wr, &bad_wr); + +out: + if (ret < 0) { + atomic_inc(&ch->sq_wr_avail); + atomic_dec(&ch->req_lim); + } + return ret; +} + +/** + * srpt_get_desc_tbl() - Parse the data descriptors of an SRP_CMD request. + * @ioctx: Pointer to the I/O context associated with the request. + * @srp_cmd: Pointer to the SRP_CMD request data. + * @dir: Pointer to the variable to which the transfer direction will be + * written. + * @data_len: Pointer to the variable to which the total data length of all + * descriptors in the SRP_CMD request will be written. + * + * 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_send_ioctx *ioctx, + struct srp_cmd *srp_cmd, + enum dma_data_direction *dir, u64 *data_len) +{ + struct srp_indirect_buf *idb; + struct srp_direct_buf *db; + unsigned add_cdb_offset; + int ret; + + /* + * 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)); + + BUG_ON(!dir); + BUG_ON(!data_len); + + ret = 0; + *data_len = 0; + + /* + * 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. + */ + *dir = DMA_NONE; + 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; + + /* + * 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". + */ + add_cdb_offset = srp_cmd->add_cdb_len & ~3; + if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_DIRECT) || + ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_DIRECT)) { + ioctx->n_rbuf = 1; + ioctx->rbufs = &ioctx->single_rbuf; + + db = (struct srp_direct_buf *)(srp_cmd->add_data + + add_cdb_offset); + memcpy(ioctx->rbufs, db, sizeof *db); + *data_len = be32_to_cpu(db->len); + } else if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_INDIRECT) || + ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_INDIRECT)) { + idb = (struct srp_indirect_buf *)(srp_cmd->add_data + + add_cdb_offset); + + ioctx->n_rbuf = be32_to_cpu(idb->table_desc.len) / sizeof *db; + + if (ioctx->n_rbuf > + (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(*db)); + ioctx->n_rbuf = 0; + ret = -EINVAL; + goto out; + } + + if (ioctx->n_rbuf == 1) + ioctx->rbufs = &ioctx->single_rbuf; + else { + ioctx->rbufs = + kmalloc(ioctx->n_rbuf * sizeof *db, GFP_ATOMIC); + if (!ioctx->rbufs) { + ioctx->n_rbuf = 0; + ret = -ENOMEM; + goto out; + } + } + + db = idb->desc_list; + memcpy(ioctx->rbufs, db, ioctx->n_rbuf * sizeof *db); + *data_len = be32_to_cpu(idb->len); + } +out: + return ret; +} + +/** + * srpt_init_ch_qp() - Initialize queue pair attributes. + * + * 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; + + attr = kzalloc(sizeof *attr, GFP_KERNEL); + if (!attr) + return -ENOMEM; + + attr->qp_state = IB_QPS_INIT; + attr->qp_access_flags = IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_READ | + IB_ACCESS_REMOTE_WRITE; + attr->port_num = ch->sport->port; + attr->pkey_index = 0; + + 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; + + qp_attr.qp_state = IB_QPS_RTR; + ret = ib_cm_init_qp_attr(ch->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->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'. + */ +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_unmap_sg_to_ib_sge() - Unmap an IB SGE list. + */ +static void srpt_unmap_sg_to_ib_sge(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx) +{ + struct scatterlist *sg; + enum dma_data_direction dir; + + BUG_ON(!ch); + BUG_ON(!ioctx); + BUG_ON(ioctx->n_rdma && !ioctx->rdma_ius); + + while (ioctx->n_rdma) + kfree(ioctx->rdma_ius[--ioctx->n_rdma].sge); + + kfree(ioctx->rdma_ius); + ioctx->rdma_ius = NULL; + + if (ioctx->mapped_sg_count) { + sg = ioctx->sg; + WARN_ON(!sg); + dir = ioctx->cmd.data_direction; + BUG_ON(dir == DMA_NONE); + ib_dma_unmap_sg(ch->sport->sdev->device, sg, ioctx->sg_cnt, + opposite_dma_dir(dir)); + ioctx->mapped_sg_count = 0; + } +} + +/** + * srpt_map_sg_to_ib_sge() - Map an SG list to an IB SGE list. + */ +static int srpt_map_sg_to_ib_sge(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx) +{ + struct ib_device *dev = ch->sport->sdev->device; + struct se_cmd *cmd; + struct scatterlist *sg, *sg_orig; + int sg_cnt; + enum dma_data_direction dir; + struct rdma_iu *riu; + struct srp_direct_buf *db; + dma_addr_t dma_addr; + struct ib_sge *sge; + u64 raddr; + u32 rsize; + u32 tsize; + u32 dma_len; + int count, nrdma; + int i, j, k; + + BUG_ON(!ch); + BUG_ON(!ioctx); + cmd = &ioctx->cmd; + dir = cmd->data_direction; + BUG_ON(dir == DMA_NONE); + + ioctx->sg = sg = sg_orig = cmd->t_data_sg; + ioctx->sg_cnt = sg_cnt = cmd->t_data_nents; + + count = ib_dma_map_sg(ch->sport->sdev->device, sg, sg_cnt, + opposite_dma_dir(dir)); + if (unlikely(!count)) + return -EAGAIN; + + ioctx->mapped_sg_count = count; + + if (ioctx->rdma_ius && ioctx->n_rdma_ius) + nrdma = ioctx->n_rdma_ius; + else { + nrdma = (count + SRPT_DEF_SG_PER_WQE - 1) / SRPT_DEF_SG_PER_WQE + + ioctx->n_rbuf; + + ioctx->rdma_ius = kzalloc(nrdma * sizeof *riu, GFP_KERNEL); + if (!ioctx->rdma_ius) + goto free_mem; + + ioctx->n_rdma_ius = nrdma; + } + + db = ioctx->rbufs; + tsize = cmd->data_length; + dma_len = ib_sg_dma_len(dev, &sg[0]); + riu = ioctx->rdma_ius; + + /* + * For each remote desc - calculate the #ib_sge. + * If #ib_sge < SRPT_DEF_SG_PER_WQE per rdma operation then + * each remote desc rdma_iu is required a rdma wr; + * else + * we need to allocate extra rdma_iu to carry extra #ib_sge in + * another rdma wr + */ + for (i = 0, j = 0; + j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) { + rsize = be32_to_cpu(db->len); + raddr = be64_to_cpu(db->va); + riu->raddr = raddr; + riu->rkey = be32_to_cpu(db->key); + riu->sge_cnt = 0; + + /* calculate how many sge required for this remote_buf */ + while (rsize > 0 && tsize > 0) { + + if (rsize >= dma_len) { + tsize -= dma_len; + rsize -= dma_len; + raddr += dma_len; + + if (tsize > 0) { + ++j; + if (j < count) { + sg = sg_next(sg); + dma_len = ib_sg_dma_len( + dev, sg); + } + } + } else { + tsize -= rsize; + dma_len -= rsize; + rsize = 0; + } + + ++riu->sge_cnt; + + if (rsize > 0 && riu->sge_cnt == SRPT_DEF_SG_PER_WQE) { + ++ioctx->n_rdma; + riu->sge = + kmalloc(riu->sge_cnt * sizeof *riu->sge, + GFP_KERNEL); + if (!riu->sge) + goto free_mem; + + ++riu; + riu->sge_cnt = 0; + riu->raddr = raddr; + riu->rkey = be32_to_cpu(db->key); + } + } + + ++ioctx->n_rdma; + riu->sge = kmalloc(riu->sge_cnt * sizeof *riu->sge, + GFP_KERNEL); + if (!riu->sge) + goto free_mem; + } + + db = ioctx->rbufs; + tsize = cmd->data_length; + riu = ioctx->rdma_ius; + sg = sg_orig; + dma_len = ib_sg_dma_len(dev, &sg[0]); + dma_addr = ib_sg_dma_address(dev, &sg[0]); + + /* this second loop is really mapped sg_addres to rdma_iu->ib_sge */ + for (i = 0, j = 0; + j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) { + rsize = be32_to_cpu(db->len); + sge = riu->sge; + k = 0; + + while (rsize > 0 && tsize > 0) { + sge->addr = dma_addr; + sge->lkey = ch->sport->sdev->mr->lkey; + + if (rsize >= dma_len) { + sge->length = + (tsize < dma_len) ? tsize : dma_len; + tsize -= dma_len; + rsize -= dma_len; + + if (tsize > 0) { + ++j; + if (j < count) { + sg = sg_next(sg); + dma_len = ib_sg_dma_len( + dev, sg); + dma_addr = ib_sg_dma_address( + dev, sg); + } + } + } else { + sge->length = (tsize < rsize) ? tsize : rsize; + tsize -= rsize; + dma_len -= rsize; + dma_addr += rsize; + rsize = 0; + } + + ++k; + if (k == riu->sge_cnt && rsize > 0 && tsize > 0) { + ++riu; + sge = riu->sge; + k = 0; + } else if (rsize > 0 && tsize > 0) + ++sge; + } + } + + return 0; + +free_mem: + srpt_unmap_sg_to_ib_sge(ch, ioctx); + + return -ENOMEM; +} + +/** + * srpt_get_send_ioctx() - Obtain an I/O context for sending to the initiator. + */ +static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch) +{ + struct srpt_send_ioctx *ioctx; + unsigned long flags; + + BUG_ON(!ch); + + ioctx = NULL; + spin_lock_irqsave(&ch->spinlock, flags); + if (!list_empty(&ch->free_list)) { + ioctx = list_first_entry(&ch->free_list, + struct srpt_send_ioctx, free_list); + list_del(&ioctx->free_list); + } + spin_unlock_irqrestore(&ch->spinlock, flags); + + if (!ioctx) + return ioctx; + + BUG_ON(ioctx->ch != ch); + spin_lock_init(&ioctx->spinlock); + ioctx->state = SRPT_STATE_NEW; + ioctx->n_rbuf = 0; + ioctx->rbufs = NULL; + ioctx->n_rdma = 0; + ioctx->n_rdma_ius = 0; + ioctx->rdma_ius = NULL; + ioctx->mapped_sg_count = 0; + init_completion(&ioctx->tx_done); + 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)); + + return ioctx; +} + +/** + * srpt_abort_cmd() - Abort a SCSI command. + * @ioctx: I/O context associated with the SCSI command. + * @context: Preferred execution context. + */ +static int srpt_abort_cmd(struct srpt_send_ioctx *ioctx) +{ + enum srpt_command_state state; + unsigned long flags; + + 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. Changing + * the state of the command from SRPT_STATE_NEED_DATA to + * SRPT_STATE_DATA_IN ensures that srpt_xmit_response() will call this + * function a second time. + */ + + spin_lock_irqsave(&ioctx->spinlock, flags); + state = ioctx->state; + switch (state) { + case SRPT_STATE_NEED_DATA: + ioctx->state = SRPT_STATE_DATA_IN; + break; + case SRPT_STATE_DATA_IN: + case SRPT_STATE_CMD_RSP_SENT: + case SRPT_STATE_MGMT_RSP_SENT: + ioctx->state = SRPT_STATE_DONE; + break; + default: + break; + } + spin_unlock_irqrestore(&ioctx->spinlock, flags); + + if (state == SRPT_STATE_DONE) { + struct srpt_rdma_ch *ch = ioctx->ch; + + BUG_ON(ch->sess == NULL); + + target_put_sess_cmd(ch->sess, &ioctx->cmd); + goto out; + } + + pr_debug("Aborting cmd with state %d and tag %lld\n", state, + ioctx->tag); + + switch (state) { + case SRPT_STATE_NEW: + case SRPT_STATE_DATA_IN: + case SRPT_STATE_MGMT: + /* + * Do nothing - defer abort processing until + * srpt_queue_response() is invoked. + */ + WARN_ON(!transport_check_aborted_status(&ioctx->cmd, false)); + break; + case SRPT_STATE_NEED_DATA: + /* DMA_TO_DEVICE (write) - RDMA read error. */ + + /* XXX(hch): this is a horrible layering violation.. */ + spin_lock_irqsave(&ioctx->cmd.t_state_lock, flags); + ioctx->cmd.transport_state &= ~CMD_T_ACTIVE; + spin_unlock_irqrestore(&ioctx->cmd.t_state_lock, flags); + break; + case SRPT_STATE_CMD_RSP_SENT: + /* + * SRP_RSP sending failed or the SRP_RSP send completion has + * not been received in time. + */ + srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx); + target_put_sess_cmd(ioctx->ch->sess, &ioctx->cmd); + break; + case SRPT_STATE_MGMT_RSP_SENT: + srpt_set_cmd_state(ioctx, SRPT_STATE_DONE); + target_put_sess_cmd(ioctx->ch->sess, &ioctx->cmd); + break; + default: + WARN(1, "Unexpected command state (%d)", state); + break; + } + +out: + return state; +} + +/** + * srpt_handle_send_err_comp() - Process an IB_WC_SEND error completion. + */ +static void srpt_handle_send_err_comp(struct srpt_rdma_ch *ch, u64 wr_id) +{ + struct srpt_send_ioctx *ioctx; + enum srpt_command_state state; + struct se_cmd *cmd; + u32 index; + + atomic_inc(&ch->sq_wr_avail); + + index = idx_from_wr_id(wr_id); + ioctx = ch->ioctx_ring[index]; + state = srpt_get_cmd_state(ioctx); + cmd = &ioctx->cmd; + + WARN_ON(state != SRPT_STATE_CMD_RSP_SENT + && state != SRPT_STATE_MGMT_RSP_SENT + && state != SRPT_STATE_NEED_DATA + && state != SRPT_STATE_DONE); + + /* If SRP_RSP sending failed, undo the ch->req_lim change. */ + if (state == SRPT_STATE_CMD_RSP_SENT + || state == SRPT_STATE_MGMT_RSP_SENT) + atomic_dec(&ch->req_lim); + + srpt_abort_cmd(ioctx); +} + +/** + * srpt_handle_send_comp() - Process an IB send completion notification. + */ +static void srpt_handle_send_comp(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx) +{ + enum srpt_command_state state; + + atomic_inc(&ch->sq_wr_avail); + + state = srpt_set_cmd_state(ioctx, SRPT_STATE_DONE); + + if (WARN_ON(state != SRPT_STATE_CMD_RSP_SENT + && state != SRPT_STATE_MGMT_RSP_SENT + && state != SRPT_STATE_DONE)) + pr_debug("state = %d\n", state); + + if (state != SRPT_STATE_DONE) { + srpt_unmap_sg_to_ib_sge(ch, ioctx); + 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_handle_rdma_comp() - Process an IB RDMA completion notification. + * + * 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_handle_rdma_comp(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx, + enum srpt_opcode opcode) +{ + WARN_ON(ioctx->n_rdma <= 0); + atomic_add(ioctx->n_rdma, &ch->sq_wr_avail); + + if (opcode == SRPT_RDMA_READ_LAST) { + 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__, srpt_get_cmd_state(ioctx)); + } else if (opcode == SRPT_RDMA_ABORT) { + ioctx->rdma_aborted = true; + } else { + WARN(true, "unexpected opcode %d\n", opcode); + } +} + +/** + * srpt_handle_rdma_err_comp() - Process an IB RDMA error completion. + */ +static void srpt_handle_rdma_err_comp(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx, + enum srpt_opcode opcode) +{ + struct se_cmd *cmd; + enum srpt_command_state state; + + cmd = &ioctx->cmd; + state = srpt_get_cmd_state(ioctx); + switch (opcode) { + case SRPT_RDMA_READ_LAST: + if (ioctx->n_rdma <= 0) { + pr_err("Received invalid RDMA read" + " error completion with idx %d\n", + ioctx->ioctx.index); + break; + } + atomic_add(ioctx->n_rdma, &ch->sq_wr_avail); + if (state == SRPT_STATE_NEED_DATA) + srpt_abort_cmd(ioctx); + else + pr_err("%s[%d]: wrong state = %d\n", + __func__, __LINE__, state); + break; + case SRPT_RDMA_WRITE_LAST: + break; + default: + pr_err("%s[%d]: opcode = %u\n", __func__, __LINE__, opcode); + break; + } +} + +/** + * srpt_build_cmd_rsp() - Build an 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 srp_rsp *srp_rsp; + const u8 *sense_data; + int sense_data_len, max_sense_len; + + /* + * 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 = + __constant_cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0)); + srp_rsp->tag = tag; + srp_rsp->status = status; + + 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 = __constant_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; +} + +#define NO_SUCH_LUN ((uint64_t)-1LL) + +/* + * SCSI LUN addressing method. See also SAM-2 and the section about + * eight byte LUNs. + */ +enum scsi_lun_addr_method { + SCSI_LUN_ADDR_METHOD_PERIPHERAL = 0, + SCSI_LUN_ADDR_METHOD_FLAT = 1, + SCSI_LUN_ADDR_METHOD_LUN = 2, + SCSI_LUN_ADDR_METHOD_EXTENDED_LUN = 3, +}; + +/* + * srpt_unpack_lun() - Convert from network LUN to linear LUN. + * + * Convert an 2-byte, 4-byte, 6-byte or 8-byte LUN structure in network byte + * order (big endian) to a linear LUN. Supports three LUN addressing methods: + * peripheral, flat and logical unit. See also SAM-2, section 4.9.4 (page 40). + */ +static uint64_t srpt_unpack_lun(const uint8_t *lun, int len) +{ + uint64_t res = NO_SUCH_LUN; + int addressing_method; + + if (unlikely(len < 2)) { + pr_err("Illegal LUN length %d, expected 2 bytes or more\n", + len); + goto out; + } + + switch (len) { + case 8: + if ((*((__be64 *)lun) & + __constant_cpu_to_be64(0x0000FFFFFFFFFFFFLL)) != 0) + goto out_err; + break; + case 4: + if (*((__be16 *)&lun[2]) != 0) + goto out_err; + break; + case 6: + if (*((__be32 *)&lun[2]) != 0) + goto out_err; + break; + case 2: + break; + default: + goto out_err; + } + + addressing_method = (*lun) >> 6; /* highest two bits of byte 0 */ + switch (addressing_method) { + case SCSI_LUN_ADDR_METHOD_PERIPHERAL: + case SCSI_LUN_ADDR_METHOD_FLAT: + case SCSI_LUN_ADDR_METHOD_LUN: + res = *(lun + 1) | (((*lun) & 0x3f) << 8); + break; + + case SCSI_LUN_ADDR_METHOD_EXTENDED_LUN: + default: + pr_err("Unimplemented LUN addressing method %u\n", + addressing_method); + break; + } + +out: + return res; + +out_err: + pr_err("Support for multi-level LUNs has not yet been implemented\n"); + goto out; +} + +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->ch->sess, &ioctx->cmd); +} + +/** + * srpt_handle_cmd() - Process SRP_CMD. + */ +static int 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; + uint64_t unpacked_lun; + u64 data_len; + enum dma_data_direction dir; + sense_reason_t ret; + int rc; + + BUG_ON(!send_ioctx); + + srp_cmd = recv_ioctx->ioctx.buf; + cmd = &send_ioctx->cmd; + send_ioctx->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; + } + + if (srpt_get_desc_tbl(send_ioctx, srp_cmd, &dir, &data_len)) { + pr_err("0x%llx: parsing SRP descriptor table failed.\n", + srp_cmd->tag); + ret = TCM_INVALID_CDB_FIELD; + goto send_sense; + } + + unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_cmd->lun, + sizeof(srp_cmd->lun)); + rc = target_submit_cmd(cmd, ch->sess, srp_cmd->cdb, + &send_ioctx->sense_data[0], unpacked_lun, data_len, + TCM_SIMPLE_TAG, dir, TARGET_SCF_ACK_KREF); + if (rc != 0) { + ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + goto send_sense; + } + return 0; + +send_sense: + transport_send_check_condition_and_sense(cmd, ret, 0); + return -1; +} + +/** + * srpt_rx_mgmt_fn_tag() - Process a task management function by tag. + * @ch: RDMA channel of the task management request. + * @fn: Task management function to perform. + * @req_tag: Tag of the SRP task management request. + * @mgmt_ioctx: I/O context of the task management request. + * + * Returns zero if the target core will process the task management + * request asynchronously. + * + * Note: It is assumed that the initiator serializes tag-based task management + * requests. + */ +static int srpt_rx_mgmt_fn_tag(struct srpt_send_ioctx *ioctx, u64 tag) +{ + struct srpt_device *sdev; + struct srpt_rdma_ch *ch; + struct srpt_send_ioctx *target; + int ret, i; + + ret = -EINVAL; + ch = ioctx->ch; + BUG_ON(!ch); + BUG_ON(!ch->sport); + sdev = ch->sport->sdev; + BUG_ON(!sdev); + spin_lock_irq(&sdev->spinlock); + for (i = 0; i < ch->rq_size; ++i) { + target = ch->ioctx_ring[i]; + if (target->cmd.se_lun == ioctx->cmd.se_lun && + target->tag == tag && + srpt_get_cmd_state(target) != SRPT_STATE_DONE) { + ret = 0; + /* now let the target core abort &target->cmd; */ + break; + } + } + spin_unlock_irq(&sdev->spinlock); + return ret; +} + +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 an SRP_TSK_MGMT information unit. + * + * 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; + uint64_t unpacked_lun; + uint32_t tag = 0; + int tcm_tmr; + int rc; + + BUG_ON(!send_ioctx); + + srp_tsk = recv_ioctx->ioctx.buf; + cmd = &send_ioctx->cmd; + + pr_debug("recv tsk_mgmt fn %d for task_tag %lld and cmd tag %lld" + " cm_id %p sess %p\n", srp_tsk->tsk_mgmt_func, + srp_tsk->task_tag, srp_tsk->tag, ch->cm_id, ch->sess); + + srpt_set_cmd_state(send_ioctx, SRPT_STATE_MGMT); + send_ioctx->tag = srp_tsk->tag; + tcm_tmr = srp_tmr_to_tcm(srp_tsk->tsk_mgmt_func); + if (tcm_tmr < 0) { + send_ioctx->cmd.se_tmr_req->response = + TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED; + goto fail; + } + unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_tsk->lun, + sizeof(srp_tsk->lun)); + + if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK) { + rc = srpt_rx_mgmt_fn_tag(send_ioctx, srp_tsk->task_tag); + if (rc < 0) { + send_ioctx->cmd.se_tmr_req->response = + TMR_TASK_DOES_NOT_EXIST; + goto fail; + } + tag = srp_tsk->task_tag; + } + rc = target_submit_tmr(&send_ioctx->cmd, sess, NULL, unpacked_lun, + srp_tsk, tcm_tmr, GFP_KERNEL, tag, + TARGET_SCF_ACK_KREF); + if (rc != 0) { + send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED; + goto fail; + } + return; +fail: + transport_send_check_condition_and_sense(cmd, 0, 0); // XXX: +} + +/** + * srpt_handle_new_iu() - Process a newly received information unit. + * @ch: RDMA channel through which the information unit has been received. + * @ioctx: SRPT I/O context associated with the information unit. + */ +static void srpt_handle_new_iu(struct srpt_rdma_ch *ch, + struct srpt_recv_ioctx *recv_ioctx, + struct srpt_send_ioctx *send_ioctx) +{ + struct srp_cmd *srp_cmd; + enum rdma_ch_state ch_state; + + BUG_ON(!ch); + BUG_ON(!recv_ioctx); + + ib_dma_sync_single_for_cpu(ch->sport->sdev->device, + recv_ioctx->ioctx.dma, srp_max_req_size, + DMA_FROM_DEVICE); + + ch_state = srpt_get_ch_state(ch); + if (unlikely(ch_state == CH_CONNECTING)) { + list_add_tail(&recv_ioctx->wait_list, &ch->cmd_wait_list); + goto out; + } + + if (unlikely(ch_state != CH_LIVE)) + goto out; + + srp_cmd = recv_ioctx->ioctx.buf; + if (srp_cmd->opcode == SRP_CMD || srp_cmd->opcode == SRP_TSK_MGMT) { + if (!send_ioctx) + send_ioctx = srpt_get_send_ioctx(ch); + if (unlikely(!send_ioctx)) { + list_add_tail(&recv_ioctx->wait_list, + &ch->cmd_wait_list); + goto out; + } + } + + switch (srp_cmd->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", + srp_cmd->opcode); + break; + } + + srpt_post_recv(ch->sport->sdev, recv_ioctx); +out: + return; +} + +static void srpt_process_rcv_completion(struct ib_cq *cq, + struct srpt_rdma_ch *ch, + struct ib_wc *wc) +{ + struct srpt_device *sdev = ch->sport->sdev; + struct srpt_recv_ioctx *ioctx; + u32 index; + + index = idx_from_wr_id(wc->wr_id); + 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 = sdev->ioctx_ring[index]; + srpt_handle_new_iu(ch, ioctx, NULL); + } else { + pr_info("receiving failed for idx %u with status %d\n", + index, wc->status); + } +} + +/** + * srpt_process_send_completion() - Process an IB send 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_process_send_completion(struct ib_cq *cq, + struct srpt_rdma_ch *ch, + struct ib_wc *wc) +{ + struct srpt_send_ioctx *send_ioctx; + uint32_t index; + enum srpt_opcode opcode; + + index = idx_from_wr_id(wc->wr_id); + opcode = opcode_from_wr_id(wc->wr_id); + send_ioctx = ch->ioctx_ring[index]; + if (wc->status == IB_WC_SUCCESS) { + if (opcode == SRPT_SEND) + srpt_handle_send_comp(ch, send_ioctx); + else { + WARN_ON(opcode != SRPT_RDMA_ABORT && + wc->opcode != IB_WC_RDMA_READ); + srpt_handle_rdma_comp(ch, send_ioctx, opcode); + } + } else { + if (opcode == SRPT_SEND) { + pr_info("sending response for idx %u failed" + " with status %d\n", index, wc->status); + srpt_handle_send_err_comp(ch, wc->wr_id); + } else if (opcode != SRPT_RDMA_MID) { + pr_info("RDMA t %d for idx %u failed with" + " status %d\n", opcode, index, wc->status); + srpt_handle_rdma_err_comp(ch, send_ioctx, opcode); + } + } + + while (unlikely(opcode == SRPT_SEND + && !list_empty(&ch->cmd_wait_list) + && srpt_get_ch_state(ch) == CH_LIVE + && (send_ioctx = srpt_get_send_ioctx(ch)) != NULL)) { + struct srpt_recv_ioctx *recv_ioctx; + + recv_ioctx = list_first_entry(&ch->cmd_wait_list, + struct srpt_recv_ioctx, + wait_list); + list_del(&recv_ioctx->wait_list); + srpt_handle_new_iu(ch, recv_ioctx, send_ioctx); + } +} + +static void srpt_process_completion(struct ib_cq *cq, struct srpt_rdma_ch *ch) +{ + struct ib_wc *const wc = ch->wc; + int i, n; + + WARN_ON(cq != ch->cq); + + ib_req_notify_cq(cq, IB_CQ_NEXT_COMP); + while ((n = ib_poll_cq(cq, ARRAY_SIZE(ch->wc), wc)) > 0) { + for (i = 0; i < n; i++) { + if (opcode_from_wr_id(wc[i].wr_id) == SRPT_RECV) + srpt_process_rcv_completion(cq, ch, &wc[i]); + else + srpt_process_send_completion(cq, ch, &wc[i]); + } + } +} + +/** + * srpt_completion() - IB completion queue callback function. + * + * Notes: + * - It is guaranteed that a completion handler will never be invoked + * concurrently on two different CPUs for the same completion queue. See also + * Documentation/infiniband/core_locking.txt and the implementation of + * handle_edge_irq() in kernel/irq/chip.c. + * - When threaded IRQs are enabled, completion handlers are invoked in thread + * context instead of interrupt context. + */ +static void srpt_completion(struct ib_cq *cq, void *ctx) +{ + struct srpt_rdma_ch *ch = ctx; + + wake_up_interruptible(&ch->wait_queue); +} + +static int srpt_compl_thread(void *arg) +{ + struct srpt_rdma_ch *ch; + + /* Hibernation / freezing of the SRPT kernel thread is not supported. */ + current->flags |= PF_NOFREEZE; + + ch = arg; + BUG_ON(!ch); + pr_info("Session %s: kernel thread %s (PID %d) started\n", + ch->sess_name, ch->thread->comm, current->pid); + while (!kthread_should_stop()) { + wait_event_interruptible(ch->wait_queue, + (srpt_process_completion(ch->cq, ch), + kthread_should_stop())); + } + pr_info("Session %s: kernel thread %s (PID %d) stopped\n", + ch->sess_name, ch->thread->comm, current->pid); + return 0; +} + +/** + * srpt_create_ch_ib() - Create receive and send completion queues. + */ +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; + u32 srp_sq_size = sport->port_attrib.srp_sq_size; + int 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_create_cq(sdev->device, srpt_completion, NULL, ch, + ch->rq_size + srp_sq_size, 0); + if (IS_ERR(ch->cq)) { + ret = PTR_ERR(ch->cq); + pr_err("failed to create CQ cqe= %d ret= %d\n", + ch->rq_size + srp_sq_size, ret); + goto out; + } + + 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->srq = sdev->srq; + qp_init->sq_sig_type = IB_SIGNAL_REQ_WR; + qp_init->qp_type = IB_QPT_RC; + qp_init->cap.max_send_wr = srp_sq_size; + qp_init->cap.max_send_sge = SRPT_DEF_SG_PER_WQE; + + ch->qp = ib_create_qp(sdev->pd, qp_init); + if (IS_ERR(ch->qp)) { + ret = PTR_ERR(ch->qp); + if (ret == -ENOMEM) { + srp_sq_size /= 2; + if (srp_sq_size >= MIN_SRPT_SQ_SIZE) { + ib_destroy_cq(ch->cq); + goto retry; + } + } + pr_err("failed to create_qp ret= %d\n", 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 cm_id= %p\n", + __func__, ch->cq->cqe, qp_init->cap.max_send_sge, + qp_init->cap.max_send_wr, ch->cm_id); + + ret = srpt_init_ch_qp(ch, ch->qp); + if (ret) + goto err_destroy_qp; + + init_waitqueue_head(&ch->wait_queue); + + pr_debug("creating thread for session %s\n", ch->sess_name); + + ch->thread = kthread_run(srpt_compl_thread, ch, "ib_srpt_compl"); + if (IS_ERR(ch->thread)) { + pr_err("failed to create kernel thread %ld\n", + PTR_ERR(ch->thread)); + ch->thread = NULL; + goto err_destroy_qp; + } + +out: + kfree(qp_init); + return ret; + +err_destroy_qp: + ib_destroy_qp(ch->qp); +err_destroy_cq: + ib_destroy_cq(ch->cq); + goto out; +} + +static void srpt_destroy_ch_ib(struct srpt_rdma_ch *ch) +{ + if (ch->thread) + kthread_stop(ch->thread); + + ib_destroy_qp(ch->qp); + ib_destroy_cq(ch->cq); +} + +/** + * __srpt_close_ch() - Close an RDMA channel by setting the QP error state. + * + * Reset the QP and make sure all resources associated with the channel will + * be deallocated at an appropriate time. + * + * Note: The caller must hold ch->sport->sdev->spinlock. + */ +static void __srpt_close_ch(struct srpt_rdma_ch *ch) +{ + struct srpt_device *sdev; + enum rdma_ch_state prev_state; + unsigned long flags; + + sdev = ch->sport->sdev; + + spin_lock_irqsave(&ch->spinlock, flags); + prev_state = ch->state; + switch (prev_state) { + case CH_CONNECTING: + case CH_LIVE: + ch->state = CH_DISCONNECTING; + break; + default: + break; + } + spin_unlock_irqrestore(&ch->spinlock, flags); + + switch (prev_state) { + case CH_CONNECTING: + ib_send_cm_rej(ch->cm_id, IB_CM_REJ_NO_RESOURCES, NULL, 0, + NULL, 0); + /* fall through */ + case CH_LIVE: + if (ib_send_cm_dreq(ch->cm_id, NULL, 0) < 0) + pr_err("sending CM DREQ failed.\n"); + break; + case CH_DISCONNECTING: + break; + case CH_DRAINING: + case CH_RELEASING: + break; + } +} + +/** + * srpt_close_ch() - Close an RDMA channel. + */ +static void srpt_close_ch(struct srpt_rdma_ch *ch) +{ + struct srpt_device *sdev; + + sdev = ch->sport->sdev; + spin_lock_irq(&sdev->spinlock); + __srpt_close_ch(ch); + spin_unlock_irq(&sdev->spinlock); +} + +/** + * srpt_shutdown_session() - Whether or not a session may be shut down. + */ +static int srpt_shutdown_session(struct se_session *se_sess) +{ + struct srpt_rdma_ch *ch = se_sess->fabric_sess_ptr; + unsigned long flags; + + spin_lock_irqsave(&ch->spinlock, flags); + if (ch->in_shutdown) { + spin_unlock_irqrestore(&ch->spinlock, flags); + return true; + } + + ch->in_shutdown = true; + target_sess_cmd_list_set_waiting(se_sess); + spin_unlock_irqrestore(&ch->spinlock, flags); + + return true; +} + +/** + * srpt_drain_channel() - Drain a channel by resetting the IB queue pair. + * @cm_id: Pointer to the CM ID of the channel to be drained. + * + * Note: Must be called from inside srpt_cm_handler to avoid a race between + * accessing sdev->spinlock and the call to kfree(sdev) in srpt_remove_one() + * (the caller of srpt_cm_handler holds the cm_id spinlock; srpt_remove_one() + * waits until all target sessions for the associated IB device have been + * unregistered and target session registration involves a call to + * ib_destroy_cm_id(), which locks the cm_id spinlock and hence waits until + * this function has finished). + */ +static void srpt_drain_channel(struct ib_cm_id *cm_id) +{ + struct srpt_device *sdev; + struct srpt_rdma_ch *ch; + int ret; + bool do_reset = false; + + WARN_ON_ONCE(irqs_disabled()); + + sdev = cm_id->context; + BUG_ON(!sdev); + spin_lock_irq(&sdev->spinlock); + list_for_each_entry(ch, &sdev->rch_list, list) { + if (ch->cm_id == cm_id) { + do_reset = srpt_test_and_set_ch_state(ch, + CH_CONNECTING, CH_DRAINING) || + srpt_test_and_set_ch_state(ch, + CH_LIVE, CH_DRAINING) || + srpt_test_and_set_ch_state(ch, + CH_DISCONNECTING, CH_DRAINING); + break; + } + } + spin_unlock_irq(&sdev->spinlock); + + if (do_reset) { + if (ch->sess) + srpt_shutdown_session(ch->sess); + + ret = srpt_ch_qp_err(ch); + if (ret < 0) + pr_err("Setting queue pair in error state" + " failed: %d\n", ret); + } +} + +/** + * srpt_find_channel() - Look up an RDMA channel. + * @cm_id: Pointer to the CM ID of the channel to be looked up. + * + * Return NULL if no matching RDMA channel has been found. + */ +static struct srpt_rdma_ch *srpt_find_channel(struct srpt_device *sdev, + struct ib_cm_id *cm_id) +{ + struct srpt_rdma_ch *ch; + bool found; + + WARN_ON_ONCE(irqs_disabled()); + BUG_ON(!sdev); + + found = false; + spin_lock_irq(&sdev->spinlock); + list_for_each_entry(ch, &sdev->rch_list, list) { + if (ch->cm_id == cm_id) { + found = true; + break; + } + } + spin_unlock_irq(&sdev->spinlock); + + return found ? ch : NULL; +} + +/** + * srpt_release_channel() - Release channel resources. + * + * Schedules the actual release because: + * - Calling the ib_destroy_cm_id() call from inside an IB CM callback would + * trigger a deadlock. + * - It is not safe to call TCM transport_* functions from interrupt context. + */ +static void srpt_release_channel(struct srpt_rdma_ch *ch) +{ + schedule_work(&ch->release_work); +} + +static void srpt_release_channel_work(struct work_struct *w) +{ + struct srpt_rdma_ch *ch; + struct srpt_device *sdev; + struct se_session *se_sess; + + ch = container_of(w, struct srpt_rdma_ch, release_work); + pr_debug("ch = %p; ch->sess = %p; release_done = %p\n", ch, ch->sess, + ch->release_done); + + sdev = ch->sport->sdev; + BUG_ON(!sdev); + + se_sess = ch->sess; + BUG_ON(!se_sess); + + target_wait_for_sess_cmds(se_sess); + + transport_deregister_session_configfs(se_sess); + transport_deregister_session(se_sess); + ch->sess = NULL; + + ib_destroy_cm_id(ch->cm_id); + + srpt_destroy_ch_ib(ch); + + srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring, + ch->sport->sdev, ch->rq_size, + ch->rsp_size, DMA_TO_DEVICE); + + spin_lock_irq(&sdev->spinlock); + list_del(&ch->list); + spin_unlock_irq(&sdev->spinlock); + + if (ch->release_done) + complete(ch->release_done); + + wake_up(&sdev->ch_releaseQ); + + kfree(ch); +} + +static struct srpt_node_acl *__srpt_lookup_acl(struct srpt_port *sport, + u8 i_port_id[16]) +{ + struct srpt_node_acl *nacl; + + list_for_each_entry(nacl, &sport->port_acl_list, list) + if (memcmp(nacl->i_port_id, i_port_id, + sizeof(nacl->i_port_id)) == 0) + return nacl; + + return NULL; +} + +static struct srpt_node_acl *srpt_lookup_acl(struct srpt_port *sport, + u8 i_port_id[16]) +{ + struct srpt_node_acl *nacl; + + spin_lock_irq(&sport->port_acl_lock); + nacl = __srpt_lookup_acl(sport, i_port_id); + spin_unlock_irq(&sport->port_acl_lock); + + return nacl; +} + +/** + * srpt_cm_req_recv() - Process the event IB_CM_REQ_RECEIVED. + * + * Ownership of the cm_id is transferred to the target session if this + * functions returns zero. Otherwise the caller remains the owner of cm_id. + */ +static int srpt_cm_req_recv(struct ib_cm_id *cm_id, + struct ib_cm_req_event_param *param, + void *private_data) +{ + struct srpt_device *sdev = cm_id->context; + struct srpt_port *sport = &sdev->port[param->port - 1]; + struct srp_login_req *req; + struct srp_login_rsp *rsp; + struct srp_login_rej *rej; + struct ib_cm_rep_param *rep_param; + struct srpt_rdma_ch *ch, *tmp_ch; + struct srpt_node_acl *nacl; + u32 it_iu_len; + int i; + int ret = 0; + + WARN_ON_ONCE(irqs_disabled()); + + if (WARN_ON(!sdev || !private_data)) + return -EINVAL; + + req = (struct srp_login_req *)private_data; + + it_iu_len = be32_to_cpu(req->req_it_iu_len); + + pr_info("Received SRP_LOGIN_REQ with i_port_id 0x%llx:0x%llx," + " t_port_id 0x%llx:0x%llx and it_iu_len %d on port %d" + " (guid=0x%llx:0x%llx)\n", + be64_to_cpu(*(__be64 *)&req->initiator_port_id[0]), + be64_to_cpu(*(__be64 *)&req->initiator_port_id[8]), + be64_to_cpu(*(__be64 *)&req->target_port_id[0]), + be64_to_cpu(*(__be64 *)&req->target_port_id[8]), + it_iu_len, + param->port, + be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[0]), + be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[8])); + + 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) { + ret = -ENOMEM; + goto out; + } + + if (it_iu_len > srp_max_req_size || it_iu_len < 64) { + rej->reason = __constant_cpu_to_be32( + SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE); + ret = -EINVAL; + 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 = __constant_cpu_to_be32( + SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + ret = -EINVAL; + pr_err("rejected SRP_LOGIN_REQ because the target port" + " has not yet been enabled\n"); + goto reject; + } + + if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) { + rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_NO_CHAN; + + spin_lock_irq(&sdev->spinlock); + + list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list) { + if (!memcmp(ch->i_port_id, req->initiator_port_id, 16) + && !memcmp(ch->t_port_id, req->target_port_id, 16) + && param->port == ch->sport->port + && param->listen_id == ch->sport->sdev->cm_id + && ch->cm_id) { + enum rdma_ch_state ch_state; + + ch_state = srpt_get_ch_state(ch); + if (ch_state != CH_CONNECTING + && ch_state != CH_LIVE) + continue; + + /* found an existing channel */ + pr_debug("Found existing channel %s" + " cm_id= %p state= %d\n", + ch->sess_name, ch->cm_id, ch_state); + + __srpt_close_ch(ch); + + rsp->rsp_flags = + SRP_LOGIN_RSP_MULTICHAN_TERMINATED; + } + } + + spin_unlock_irq(&sdev->spinlock); + + } else + rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED; + + 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 = __constant_cpu_to_be32( + SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL); + ret = -ENOMEM; + pr_err("rejected SRP_LOGIN_REQ because it" + " has an invalid target port identifier.\n"); + goto reject; + } + + ch = kzalloc(sizeof *ch, GFP_KERNEL); + if (!ch) { + rej->reason = __constant_cpu_to_be32( + SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_err("rejected SRP_LOGIN_REQ because no memory.\n"); + ret = -ENOMEM; + goto reject; + } + + INIT_WORK(&ch->release_work, srpt_release_channel_work); + memcpy(ch->i_port_id, req->initiator_port_id, 16); + memcpy(ch->t_port_id, req->target_port_id, 16); + ch->sport = &sdev->port[param->port - 1]; + ch->cm_id = cm_id; + /* + * Avoid QUEUE_FULL conditions by limiting the number of buffers used + * for the SRP protocol to the command queue size. + */ + ch->rq_size = SRPT_RQ_SIZE; + spin_lock_init(&ch->spinlock); + ch->state = CH_CONNECTING; + INIT_LIST_HEAD(&ch->cmd_wait_list); + ch->rsp_size = ch->sport->port_attrib.srp_max_rsp_size; + + ch->ioctx_ring = (struct srpt_send_ioctx **) + srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size, + sizeof(*ch->ioctx_ring[0]), + ch->rsp_size, DMA_TO_DEVICE); + if (!ch->ioctx_ring) + goto free_ch; + + INIT_LIST_HEAD(&ch->free_list); + for (i = 0; i < ch->rq_size; i++) { + ch->ioctx_ring[i]->ch = ch; + list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list); + } + + ret = srpt_create_ch_ib(ch); + if (ret) { + rej->reason = __constant_cpu_to_be32( + SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_err("rejected SRP_LOGIN_REQ because creating" + " a new RDMA channel failed.\n"); + goto free_ring; + } + + ret = srpt_ch_qp_rtr(ch, ch->qp); + if (ret) { + rej->reason = __constant_cpu_to_be32( + SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_err("rejected SRP_LOGIN_REQ because enabling" + " RTR failed (error code = %d)\n", ret); + goto destroy_ib; + } + /* + * Use the initator port identifier as the session name. + */ + snprintf(ch->sess_name, sizeof(ch->sess_name), "0x%016llx%016llx", + be64_to_cpu(*(__be64 *)ch->i_port_id), + be64_to_cpu(*(__be64 *)(ch->i_port_id + 8))); + + pr_debug("registering session %s\n", ch->sess_name); + + nacl = srpt_lookup_acl(sport, ch->i_port_id); + if (!nacl) { + pr_info("Rejected login because no ACL has been" + " configured yet for initiator %s.\n", ch->sess_name); + rej->reason = __constant_cpu_to_be32( + SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED); + goto destroy_ib; + } + + ch->sess = transport_init_session(TARGET_PROT_NORMAL); + if (IS_ERR(ch->sess)) { + rej->reason = __constant_cpu_to_be32( + SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES); + pr_debug("Failed to create session\n"); + goto deregister_session; + } + ch->sess->se_node_acl = &nacl->nacl; + transport_register_session(&sport->port_tpg_1, &nacl->nacl, ch->sess, ch); + + pr_debug("Establish connection sess=%p name=%s cm_id=%p\n", ch->sess, + ch->sess_name, ch->cm_id); + + /* create srp_login_response */ + rsp->opcode = SRP_LOGIN_RSP; + rsp->tag = req->tag; + rsp->max_it_iu_len = req->req_it_iu_len; + rsp->max_ti_iu_len = req->req_it_iu_len; + ch->max_ti_iu_len = it_iu_len; + rsp->buf_fmt = __constant_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 */ + rep_param->qp_num = ch->qp->qp_num; + rep_param->private_data = (void *)rsp; + rep_param->private_data_len = sizeof *rsp; + rep_param->rnr_retry_count = 7; + rep_param->flow_control = 1; + rep_param->failover_accepted = 0; + rep_param->srq = 1; + rep_param->responder_resources = 4; + rep_param->initiator_depth = 4; + + ret = ib_send_cm_rep(cm_id, rep_param); + if (ret) { + pr_err("sending SRP_LOGIN_REQ response failed" + " (error code = %d)\n", ret); + goto release_channel; + } + + spin_lock_irq(&sdev->spinlock); + list_add_tail(&ch->list, &sdev->rch_list); + spin_unlock_irq(&sdev->spinlock); + + goto out; + +release_channel: + srpt_set_ch_state(ch, CH_RELEASING); + transport_deregister_session_configfs(ch->sess); + +deregister_session: + transport_deregister_session(ch->sess); + ch->sess = NULL; + +destroy_ib: + srpt_destroy_ch_ib(ch); + +free_ring: + srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring, + ch->sport->sdev, ch->rq_size, + ch->rsp_size, DMA_TO_DEVICE); +free_ch: + kfree(ch); + +reject: + rej->opcode = SRP_LOGIN_REJ; + rej->tag = req->tag; + rej->buf_fmt = __constant_cpu_to_be16(SRP_BUF_FORMAT_DIRECT + | SRP_BUF_FORMAT_INDIRECT); + + ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED, NULL, 0, + (void *)rej, sizeof *rej); + +out: + kfree(rep_param); + kfree(rsp); + kfree(rej); + + return ret; +} + +static void srpt_cm_rej_recv(struct ib_cm_id *cm_id) +{ + pr_info("Received IB REJ for cm_id %p.\n", cm_id); + srpt_drain_channel(cm_id); +} + +/** + * srpt_cm_rtu_recv() - Process an IB_CM_RTU_RECEIVED or USER_ESTABLISHED event. + * + * An IB_CM_RTU_RECEIVED message indicates that the connection is established + * and that the recipient may begin transmitting (RTU = ready to use). + */ +static void srpt_cm_rtu_recv(struct ib_cm_id *cm_id) +{ + struct srpt_rdma_ch *ch; + int ret; + + ch = srpt_find_channel(cm_id->context, cm_id); + BUG_ON(!ch); + + if (srpt_test_and_set_ch_state(ch, CH_CONNECTING, CH_LIVE)) { + struct srpt_recv_ioctx *ioctx, *ioctx_tmp; + + ret = srpt_ch_qp_rts(ch, ch->qp); + + list_for_each_entry_safe(ioctx, ioctx_tmp, &ch->cmd_wait_list, + wait_list) { + list_del(&ioctx->wait_list); + srpt_handle_new_iu(ch, ioctx, NULL); + } + if (ret) + srpt_close_ch(ch); + } +} + +static void srpt_cm_timewait_exit(struct ib_cm_id *cm_id) +{ + pr_info("Received IB TimeWait exit for cm_id %p.\n", cm_id); + srpt_drain_channel(cm_id); +} + +static void srpt_cm_rep_error(struct ib_cm_id *cm_id) +{ + pr_info("Received IB REP error for cm_id %p.\n", cm_id); + srpt_drain_channel(cm_id); +} + +/** + * srpt_cm_dreq_recv() - Process reception of a DREQ message. + */ +static void srpt_cm_dreq_recv(struct ib_cm_id *cm_id) +{ + struct srpt_rdma_ch *ch; + unsigned long flags; + bool send_drep = false; + + ch = srpt_find_channel(cm_id->context, cm_id); + BUG_ON(!ch); + + pr_debug("cm_id= %p ch->state= %d\n", cm_id, srpt_get_ch_state(ch)); + + spin_lock_irqsave(&ch->spinlock, flags); + switch (ch->state) { + case CH_CONNECTING: + case CH_LIVE: + send_drep = true; + ch->state = CH_DISCONNECTING; + break; + case CH_DISCONNECTING: + case CH_DRAINING: + case CH_RELEASING: + WARN(true, "unexpected channel state %d\n", ch->state); + break; + } + spin_unlock_irqrestore(&ch->spinlock, flags); + + if (send_drep) { + if (ib_send_cm_drep(ch->cm_id, NULL, 0) < 0) + pr_err("Sending IB DREP failed.\n"); + pr_info("Received DREQ and sent DREP for session %s.\n", + ch->sess_name); + } +} + +/** + * srpt_cm_drep_recv() - Process reception of a DREP message. + */ +static void srpt_cm_drep_recv(struct ib_cm_id *cm_id) +{ + pr_info("Received InfiniBand DREP message for cm_id %p.\n", cm_id); + srpt_drain_channel(cm_id); +} + +/** + * srpt_cm_handler() - IB connection manager callback function. + * + * 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, struct ib_cm_event *event) +{ + int ret; + + ret = 0; + switch (event->event) { + case IB_CM_REQ_RECEIVED: + ret = srpt_cm_req_recv(cm_id, &event->param.req_rcvd, + event->private_data); + break; + case IB_CM_REJ_RECEIVED: + srpt_cm_rej_recv(cm_id); + break; + case IB_CM_RTU_RECEIVED: + case IB_CM_USER_ESTABLISHED: + srpt_cm_rtu_recv(cm_id); + break; + case IB_CM_DREQ_RECEIVED: + srpt_cm_dreq_recv(cm_id); + break; + case IB_CM_DREP_RECEIVED: + srpt_cm_drep_recv(cm_id); + break; + case IB_CM_TIMEWAIT_EXIT: + srpt_cm_timewait_exit(cm_id); + break; + case IB_CM_REP_ERROR: + srpt_cm_rep_error(cm_id); + break; + case IB_CM_DREQ_ERROR: + pr_info("Received IB DREQ ERROR event.\n"); + break; + case IB_CM_MRA_RECEIVED: + pr_info("Received IB MRA event\n"); + break; + default: + pr_err("received unrecognized IB CM event %d\n", event->event); + break; + } + + return ret; +} + +/** + * srpt_perform_rdmas() - Perform IB RDMA. + * + * Returns zero upon success or a negative number upon failure. + */ +static int srpt_perform_rdmas(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx) +{ + struct ib_send_wr wr; + struct ib_send_wr *bad_wr; + struct rdma_iu *riu; + int i; + int ret; + int sq_wr_avail; + enum dma_data_direction dir; + const int n_rdma = ioctx->n_rdma; + + dir = ioctx->cmd.data_direction; + if (dir == DMA_TO_DEVICE) { + /* write */ + ret = -ENOMEM; + sq_wr_avail = atomic_sub_return(n_rdma, &ch->sq_wr_avail); + if (sq_wr_avail < 0) { + pr_warn("IB send queue full (needed %d)\n", + n_rdma); + goto out; + } + } + + ioctx->rdma_aborted = false; + ret = 0; + riu = ioctx->rdma_ius; + memset(&wr, 0, sizeof wr); + + for (i = 0; i < n_rdma; ++i, ++riu) { + if (dir == DMA_FROM_DEVICE) { + wr.opcode = IB_WR_RDMA_WRITE; + wr.wr_id = encode_wr_id(i == n_rdma - 1 ? + SRPT_RDMA_WRITE_LAST : + SRPT_RDMA_MID, + ioctx->ioctx.index); + } else { + wr.opcode = IB_WR_RDMA_READ; + wr.wr_id = encode_wr_id(i == n_rdma - 1 ? + SRPT_RDMA_READ_LAST : + SRPT_RDMA_MID, + ioctx->ioctx.index); + } + wr.next = NULL; + wr.wr.rdma.remote_addr = riu->raddr; + wr.wr.rdma.rkey = riu->rkey; + wr.num_sge = riu->sge_cnt; + wr.sg_list = riu->sge; + + /* only get completion event for the last rdma write */ + if (i == (n_rdma - 1) && dir == DMA_TO_DEVICE) + wr.send_flags = IB_SEND_SIGNALED; + + ret = ib_post_send(ch->qp, &wr, &bad_wr); + if (ret) + break; + } + + if (ret) + pr_err("%s[%d]: ib_post_send() returned %d for %d/%d\n", + __func__, __LINE__, ret, i, n_rdma); + if (ret && i > 0) { + wr.num_sge = 0; + wr.wr_id = encode_wr_id(SRPT_RDMA_ABORT, ioctx->ioctx.index); + wr.send_flags = IB_SEND_SIGNALED; + while (ch->state == CH_LIVE && + ib_post_send(ch->qp, &wr, &bad_wr) != 0) { + pr_info("Trying to abort failed RDMA transfer [%d]\n", + ioctx->ioctx.index); + msleep(1000); + } + while (ch->state != CH_RELEASING && !ioctx->rdma_aborted) { + pr_info("Waiting until RDMA abort finished [%d]\n", + ioctx->ioctx.index); + msleep(1000); + } + } +out: + if (unlikely(dir == DMA_TO_DEVICE && ret < 0)) + atomic_add(n_rdma, &ch->sq_wr_avail); + return ret; +} + +/** + * srpt_xfer_data() - Start data transfer from initiator to target. + */ +static int srpt_xfer_data(struct srpt_rdma_ch *ch, + struct srpt_send_ioctx *ioctx) +{ + int ret; + + ret = srpt_map_sg_to_ib_sge(ch, ioctx); + if (ret) { + pr_err("%s[%d] ret=%d\n", __func__, __LINE__, ret); + goto out; + } + + ret = srpt_perform_rdmas(ch, ioctx); + if (ret) { + if (ret == -EAGAIN || ret == -ENOMEM) + pr_info("%s[%d] queue full -- ret=%d\n", + __func__, __LINE__, ret); + else + pr_err("%s[%d] fatal error -- ret=%d\n", + __func__, __LINE__, ret); + goto out_unmap; + } + +out: + return ret; +out_unmap: + srpt_unmap_sg_to_ib_sge(ch, ioctx); + goto out; +} + +static int srpt_write_pending_status(struct se_cmd *se_cmd) +{ + struct srpt_send_ioctx *ioctx; + + ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd); + return srpt_get_cmd_state(ioctx) == SRPT_STATE_NEED_DATA; +} + +/* + * srpt_write_pending() - Start data transfer from initiator to target (write). + */ +static int srpt_write_pending(struct se_cmd *se_cmd) +{ + struct srpt_rdma_ch *ch; + struct srpt_send_ioctx *ioctx; + enum srpt_command_state new_state; + enum rdma_ch_state ch_state; + int ret; + + ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd); + + new_state = srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA); + WARN_ON(new_state == SRPT_STATE_DONE); + + ch = ioctx->ch; + BUG_ON(!ch); + + ch_state = srpt_get_ch_state(ch); + switch (ch_state) { + case CH_CONNECTING: + WARN(true, "unexpected channel state %d\n", ch_state); + ret = -EINVAL; + goto out; + case CH_LIVE: + break; + case CH_DISCONNECTING: + case CH_DRAINING: + case CH_RELEASING: + pr_debug("cmd with tag %lld: channel disconnecting\n", + ioctx->tag); + srpt_set_cmd_state(ioctx, SRPT_STATE_DATA_IN); + ret = -EINVAL; + goto out; + } + ret = srpt_xfer_data(ch, ioctx); + +out: + 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() - Transmits the response to a SCSI 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_rdma_ch *ch; + struct srpt_send_ioctx *ioctx; + enum srpt_command_state state; + unsigned long flags; + int ret; + enum dma_data_direction dir; + int resp_len; + u8 srp_tm_status; + + ioctx = container_of(cmd, struct srpt_send_ioctx, cmd); + ch = ioctx->ch; + BUG_ON(!ch); + + spin_lock_irqsave(&ioctx->spinlock, flags); + 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; + } + spin_unlock_irqrestore(&ioctx->spinlock, flags); + + if (unlikely(transport_check_aborted_status(&ioctx->cmd, false) + || WARN_ON_ONCE(state == SRPT_STATE_CMD_RSP_SENT))) { + atomic_inc(&ch->req_lim_delta); + srpt_abort_cmd(ioctx); + return; + } + + dir = ioctx->cmd.data_direction; + + /* For read commands, transfer the data to the initiator. */ + if (dir == DMA_FROM_DEVICE && ioctx->cmd.data_length && + !ioctx->queue_status_only) { + ret = srpt_xfer_data(ch, ioctx); + if (ret) { + pr_err("xfer_data failed for tag %llu\n", + ioctx->tag); + return; + } + } + + if (state != SRPT_STATE_MGMT) + resp_len = srpt_build_cmd_rsp(ch, ioctx, ioctx->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->tag); + } + ret = srpt_post_send(ch, ioctx, resp_len); + if (ret) { + pr_err("sending cmd response failed for tag %llu\n", + ioctx->tag); + srpt_unmap_sg_to_ib_sge(ch, ioctx); + srpt_set_cmd_state(ioctx, SRPT_STATE_DONE); + target_put_sess_cmd(ioctx->ch->sess, &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); +} + +static void srpt_aborted_task(struct se_cmd *cmd) +{ + struct srpt_send_ioctx *ioctx = container_of(cmd, + struct srpt_send_ioctx, cmd); + + srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx); +} + +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); +} + +static int srpt_ch_list_empty(struct srpt_device *sdev) +{ + int res; + + spin_lock_irq(&sdev->spinlock); + res = list_empty(&sdev->rch_list); + spin_unlock_irq(&sdev->spinlock); + + return res; +} + +/** + * srpt_release_sdev() - Free the channel resources associated with a target. + */ +static int srpt_release_sdev(struct srpt_device *sdev) +{ + struct srpt_rdma_ch *ch, *tmp_ch; + int res; + + WARN_ON_ONCE(irqs_disabled()); + + BUG_ON(!sdev); + + spin_lock_irq(&sdev->spinlock); + list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list) + __srpt_close_ch(ch); + spin_unlock_irq(&sdev->spinlock); + + res = wait_event_interruptible(sdev->ch_releaseQ, + srpt_ch_list_empty(sdev)); + if (res) + pr_err("%s: interrupted.\n", __func__); + + return 0; +} + +static struct srpt_port *__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->port_guid, name)) + return sport; + } + } + + return NULL; +} + +static struct srpt_port *srpt_lookup_port(const char *name) +{ + struct srpt_port *sport; + + spin_lock(&srpt_dev_lock); + sport = __srpt_lookup_port(name); + spin_unlock(&srpt_dev_lock); + + return sport; +} + +/** + * srpt_add_one() - Infiniband device addition callback function. + */ +static void srpt_add_one(struct ib_device *device) +{ + struct srpt_device *sdev; + struct srpt_port *sport; + struct ib_srq_init_attr srq_attr; + int i; + + pr_debug("device = %p, device->dma_ops = %p\n", device, + device->dma_ops); + + sdev = kzalloc(sizeof *sdev, GFP_KERNEL); + if (!sdev) + goto err; + + sdev->device = device; + INIT_LIST_HEAD(&sdev->rch_list); + init_waitqueue_head(&sdev->ch_releaseQ); + spin_lock_init(&sdev->spinlock); + + if (ib_query_device(device, &sdev->dev_attr)) + goto free_dev; + + sdev->pd = ib_alloc_pd(device); + if (IS_ERR(sdev->pd)) + goto free_dev; + + sdev->mr = ib_get_dma_mr(sdev->pd, IB_ACCESS_LOCAL_WRITE); + if (IS_ERR(sdev->mr)) + goto err_pd; + + sdev->srq_size = min(srpt_srq_size, sdev->dev_attr.max_srq_wr); + + srq_attr.event_handler = srpt_srq_event; + srq_attr.srq_context = (void *)sdev; + srq_attr.attr.max_wr = sdev->srq_size; + srq_attr.attr.max_sge = 1; + srq_attr.attr.srq_limit = 0; + srq_attr.srq_type = IB_SRQT_BASIC; + + sdev->srq = ib_create_srq(sdev->pd, &srq_attr); + if (IS_ERR(sdev->srq)) + goto err_mr; + + pr_debug("%s: create SRQ #wr= %d max_allow=%d dev= %s\n", + __func__, sdev->srq_size, sdev->dev_attr.max_srq_wr, + device->name); + + if (!srpt_service_guid) + srpt_service_guid = be64_to_cpu(device->node_guid); + + sdev->cm_id = ib_create_cm_id(device, srpt_cm_handler, sdev); + if (IS_ERR(sdev->cm_id)) + goto err_srq; + + /* 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 + */ + if (ib_cm_listen(sdev->cm_id, cpu_to_be64(srpt_service_guid), 0, NULL)) + goto err_cm; + + INIT_IB_EVENT_HANDLER(&sdev->event_handler, sdev->device, + srpt_event_handler); + if (ib_register_event_handler(&sdev->event_handler)) + goto err_cm; + + sdev->ioctx_ring = (struct srpt_recv_ioctx **) + srpt_alloc_ioctx_ring(sdev, sdev->srq_size, + sizeof(*sdev->ioctx_ring[0]), + srp_max_req_size, DMA_FROM_DEVICE); + if (!sdev->ioctx_ring) + goto err_event; + + for (i = 0; i < sdev->srq_size; ++i) + srpt_post_recv(sdev, sdev->ioctx_ring[i]); + + WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port)); + + for (i = 1; i <= sdev->device->phys_port_cnt; i++) { + sport = &sdev->port[i - 1]; + 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; + INIT_WORK(&sport->work, srpt_refresh_port_work); + INIT_LIST_HEAD(&sport->port_acl_list); + spin_lock_init(&sport->port_acl_lock); + + if (srpt_refresh_port(sport)) { + pr_err("MAD registration failed for %s-%d.\n", + srpt_sdev_name(sdev), i); + goto err_ring; + } + snprintf(sport->port_guid, sizeof(sport->port_guid), + "0x%016llx%016llx", + be64_to_cpu(sport->gid.global.subnet_prefix), + be64_to_cpu(sport->gid.global.interface_id)); + } + + spin_lock(&srpt_dev_lock); + list_add_tail(&sdev->list, &srpt_dev_list); + spin_unlock(&srpt_dev_lock); + +out: + ib_set_client_data(device, &srpt_client, sdev); + pr_debug("added %s.\n", device->name); + return; + +err_ring: + srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev, + sdev->srq_size, srp_max_req_size, + DMA_FROM_DEVICE); +err_event: + ib_unregister_event_handler(&sdev->event_handler); +err_cm: + ib_destroy_cm_id(sdev->cm_id); +err_srq: + ib_destroy_srq(sdev->srq); +err_mr: + ib_dereg_mr(sdev->mr); +err_pd: + ib_dealloc_pd(sdev->pd); +free_dev: + kfree(sdev); +err: + sdev = NULL; + pr_info("%s(%s) failed.\n", __func__, device->name); + goto out; +} + +/** + * srpt_remove_one() - InfiniBand device removal callback function. + */ +static void srpt_remove_one(struct ib_device *device) +{ + struct srpt_device *sdev; + int i; + + sdev = ib_get_client_data(device, &srpt_client); + if (!sdev) { + pr_info("%s(%s): nothing to do.\n", __func__, device->name); + return; + } + + srpt_unregister_mad_agent(sdev); + + 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); + + ib_destroy_cm_id(sdev->cm_id); + + /* + * 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); + srpt_release_sdev(sdev); + + ib_destroy_srq(sdev->srq); + ib_dereg_mr(sdev->mr); + ib_dealloc_pd(sdev->pd); + + srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev, + sdev->srq_size, srp_max_req_size, DMA_FROM_DEVICE); + sdev->ioctx_ring = NULL; + kfree(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 char *srpt_get_fabric_name(void) +{ + return "srpt"; +} + +static u8 srpt_get_fabric_proto_ident(struct se_portal_group *se_tpg) +{ + return SCSI_TRANSPORTID_PROTOCOLID_SRP; +} + +static char *srpt_get_fabric_wwn(struct se_portal_group *tpg) +{ + struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1); + + return sport->port_guid; +} + +static u16 srpt_get_tag(struct se_portal_group *tpg) +{ + return 1; +} + +static u32 srpt_get_default_depth(struct se_portal_group *se_tpg) +{ + return 1; +} + +static u32 srpt_get_pr_transport_id(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl, + struct t10_pr_registration *pr_reg, + int *format_code, unsigned char *buf) +{ + struct srpt_node_acl *nacl; + struct spc_rdma_transport_id *tr_id; + + nacl = container_of(se_nacl, struct srpt_node_acl, nacl); + tr_id = (void *)buf; + tr_id->protocol_identifier = SCSI_TRANSPORTID_PROTOCOLID_SRP; + memcpy(tr_id->i_port_id, nacl->i_port_id, sizeof(tr_id->i_port_id)); + return sizeof(*tr_id); +} + +static u32 srpt_get_pr_transport_id_len(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl, + struct t10_pr_registration *pr_reg, + int *format_code) +{ + *format_code = 0; + return sizeof(struct spc_rdma_transport_id); +} + +static char *srpt_parse_pr_out_transport_id(struct se_portal_group *se_tpg, + const char *buf, u32 *out_tid_len, + char **port_nexus_ptr) +{ + struct spc_rdma_transport_id *tr_id; + + *port_nexus_ptr = NULL; + *out_tid_len = sizeof(struct spc_rdma_transport_id); + tr_id = (void *)buf; + return (char *)tr_id->i_port_id; +} + +static struct se_node_acl *srpt_alloc_fabric_acl(struct se_portal_group *se_tpg) +{ + struct srpt_node_acl *nacl; + + nacl = kzalloc(sizeof(struct srpt_node_acl), GFP_KERNEL); + if (!nacl) { + pr_err("Unable to allocate struct srpt_node_acl\n"); + return NULL; + } + + return &nacl->nacl; +} + +static void srpt_release_fabric_acl(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl) +{ + struct srpt_node_acl *nacl; + + nacl = container_of(se_nacl, struct srpt_node_acl, nacl); + kfree(nacl); +} + +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; + unsigned long flags; + + WARN_ON(ioctx->state != SRPT_STATE_DONE); + WARN_ON(ioctx->mapped_sg_count != 0); + + if (ioctx->n_rbuf > 1) { + kfree(ioctx->rbufs); + ioctx->rbufs = NULL; + ioctx->n_rbuf = 0; + } + + spin_lock_irqsave(&ch->spinlock, flags); + list_add(&ioctx->free_list, &ch->free_list); + spin_unlock_irqrestore(&ch->spinlock, flags); +} + +/** + * srpt_close_session() - Forcibly close a 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) +{ + DECLARE_COMPLETION_ONSTACK(release_done); + struct srpt_rdma_ch *ch; + struct srpt_device *sdev; + unsigned long res; + + ch = se_sess->fabric_sess_ptr; + WARN_ON(ch->sess != se_sess); + + pr_debug("ch %p state %d\n", ch, srpt_get_ch_state(ch)); + + sdev = ch->sport->sdev; + spin_lock_irq(&sdev->spinlock); + BUG_ON(ch->release_done); + ch->release_done = &release_done; + __srpt_close_ch(ch); + spin_unlock_irq(&sdev->spinlock); + + res = wait_for_completion_timeout(&release_done, 60 * HZ); + WARN_ON(res == 0); +} + +/** + * srpt_sess_get_index() - Return the value of scsiAttIntrPortIndex (SCSI-MIB). + * + * 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) +{ +} + +static u32 srpt_get_task_tag(struct se_cmd *se_cmd) +{ + struct srpt_send_ioctx *ioctx; + + ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd); + return ioctx->tag; +} + +/* 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 srpt_get_cmd_state(ioctx); +} + +/** + * 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, rc; + + 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); + rc = hex2bin(i_port_id + leading_zero_bytes, p, count); + if (rc < 0) + pr_debug("hex2bin failed for srpt_parse_i_port_id: %d\n", rc); + ret = 0; +out: + return ret; +} + +/* + * configfs callback function invoked for + * mkdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id + */ +static struct se_node_acl *srpt_make_nodeacl(struct se_portal_group *tpg, + struct config_group *group, + const char *name) +{ + struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1); + struct se_node_acl *se_nacl, *se_nacl_new; + struct srpt_node_acl *nacl; + int ret = 0; + u32 nexus_depth = 1; + u8 i_port_id[16]; + + if (srpt_parse_i_port_id(i_port_id, name) < 0) { + pr_err("invalid initiator port ID %s\n", name); + ret = -EINVAL; + goto err; + } + + se_nacl_new = srpt_alloc_fabric_acl(tpg); + if (!se_nacl_new) { + ret = -ENOMEM; + goto err; + } + /* + * nacl_new may be released by core_tpg_add_initiator_node_acl() + * when converting a node ACL from demo mode to explict + */ + se_nacl = core_tpg_add_initiator_node_acl(tpg, se_nacl_new, name, + nexus_depth); + if (IS_ERR(se_nacl)) { + ret = PTR_ERR(se_nacl); + goto err; + } + /* Locate our struct srpt_node_acl and set sdev and i_port_id. */ + nacl = container_of(se_nacl, struct srpt_node_acl, nacl); + memcpy(&nacl->i_port_id[0], &i_port_id[0], 16); + nacl->sport = sport; + + spin_lock_irq(&sport->port_acl_lock); + list_add_tail(&nacl->list, &sport->port_acl_list); + spin_unlock_irq(&sport->port_acl_lock); + + return se_nacl; +err: + return ERR_PTR(ret); +} + +/* + * configfs callback function invoked for + * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id + */ +static void srpt_drop_nodeacl(struct se_node_acl *se_nacl) +{ + struct srpt_node_acl *nacl; + struct srpt_device *sdev; + struct srpt_port *sport; + + nacl = container_of(se_nacl, struct srpt_node_acl, nacl); + sport = nacl->sport; + sdev = sport->sdev; + spin_lock_irq(&sport->port_acl_lock); + list_del(&nacl->list); + spin_unlock_irq(&sport->port_acl_lock); + core_tpg_del_initiator_node_acl(&sport->port_tpg_1, se_nacl, 1); + srpt_release_fabric_acl(NULL, se_nacl); +} + +static ssize_t srpt_tpg_attrib_show_srp_max_rdma_size( + struct se_portal_group *se_tpg, + char *page) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + + return sprintf(page, "%u\n", sport->port_attrib.srp_max_rdma_size); +} + +static ssize_t srpt_tpg_attrib_store_srp_max_rdma_size( + struct se_portal_group *se_tpg, + const char *page, + size_t count) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + 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; +} + +TF_TPG_ATTRIB_ATTR(srpt, srp_max_rdma_size, S_IRUGO | S_IWUSR); + +static ssize_t srpt_tpg_attrib_show_srp_max_rsp_size( + struct se_portal_group *se_tpg, + char *page) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + + return sprintf(page, "%u\n", sport->port_attrib.srp_max_rsp_size); +} + +static ssize_t srpt_tpg_attrib_store_srp_max_rsp_size( + struct se_portal_group *se_tpg, + const char *page, + size_t count) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + 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; +} + +TF_TPG_ATTRIB_ATTR(srpt, srp_max_rsp_size, S_IRUGO | S_IWUSR); + +static ssize_t srpt_tpg_attrib_show_srp_sq_size( + struct se_portal_group *se_tpg, + char *page) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + + return sprintf(page, "%u\n", sport->port_attrib.srp_sq_size); +} + +static ssize_t srpt_tpg_attrib_store_srp_sq_size( + struct se_portal_group *se_tpg, + const char *page, + size_t count) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + 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; +} + +TF_TPG_ATTRIB_ATTR(srpt, srp_sq_size, S_IRUGO | S_IWUSR); + +static struct configfs_attribute *srpt_tpg_attrib_attrs[] = { + &srpt_tpg_attrib_srp_max_rdma_size.attr, + &srpt_tpg_attrib_srp_max_rsp_size.attr, + &srpt_tpg_attrib_srp_sq_size.attr, + NULL, +}; + +static ssize_t srpt_tpg_show_enable( + struct se_portal_group *se_tpg, + char *page) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + + return snprintf(page, PAGE_SIZE, "%d\n", (sport->enabled) ? 1: 0); +} + +static ssize_t srpt_tpg_store_enable( + struct se_portal_group *se_tpg, + const char *page, + size_t count) +{ + struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1); + 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; + } + if (tmp == 1) + sport->enabled = true; + else + sport->enabled = false; + + return count; +} + +TF_TPG_BASE_ATTR(srpt, enable, S_IRUGO | S_IWUSR); + +static struct configfs_attribute *srpt_tpg_attrs[] = { + &srpt_tpg_enable.attr, + NULL, +}; + +/** + * configfs callback invoked for + * mkdir /sys/kernel/config/target/$driver/$port/$tpg + */ +static struct se_portal_group *srpt_make_tpg(struct se_wwn *wwn, + struct config_group *group, + const char *name) +{ + struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn); + int res; + + /* Initialize sport->port_wwn and sport->port_tpg_1 */ + res = core_tpg_register(&srpt_template, &sport->port_wwn, + &sport->port_tpg_1, sport, TRANSPORT_TPG_TYPE_NORMAL); + if (res) + return ERR_PTR(res); + + return &sport->port_tpg_1; +} + +/** + * configfs callback invoked for + * rmdir /sys/kernel/config/target/$driver/$port/$tpg + */ +static void srpt_drop_tpg(struct se_portal_group *tpg) +{ + struct srpt_port *sport = container_of(tpg, + struct srpt_port, port_tpg_1); + + sport->enabled = false; + core_tpg_deregister(&sport->port_tpg_1); +} + +/** + * configfs callback invoked for + * mkdir /sys/kernel/config/target/$driver/$port + */ +static struct se_wwn *srpt_make_tport(struct target_fabric_configfs *tf, + struct config_group *group, + const char *name) +{ + struct srpt_port *sport; + int ret; + + sport = srpt_lookup_port(name); + pr_debug("make_tport(%s)\n", name); + ret = -EINVAL; + if (!sport) + goto err; + + return &sport->port_wwn; + +err: + return ERR_PTR(ret); +} + +/** + * configfs callback invoked for + * rmdir /sys/kernel/config/target/$driver/$port + */ +static void srpt_drop_tport(struct se_wwn *wwn) +{ + struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn); + + pr_debug("drop_tport(%s\n", config_item_name(&sport->port_wwn.wwn_group.cg_item)); +} + +static ssize_t srpt_wwn_show_attr_version(struct target_fabric_configfs *tf, + char *buf) +{ + return scnprintf(buf, PAGE_SIZE, "%s\n", DRV_VERSION); +} + +TF_WWN_ATTR_RO(srpt, version); + +static struct configfs_attribute *srpt_wwn_attrs[] = { + &srpt_wwn_version.attr, + NULL, +}; + +static const struct target_core_fabric_ops srpt_template = { + .module = THIS_MODULE, + .name = "srpt", + .get_fabric_name = srpt_get_fabric_name, + .get_fabric_proto_ident = srpt_get_fabric_proto_ident, + .tpg_get_wwn = srpt_get_fabric_wwn, + .tpg_get_tag = srpt_get_tag, + .tpg_get_default_depth = srpt_get_default_depth, + .tpg_get_pr_transport_id = srpt_get_pr_transport_id, + .tpg_get_pr_transport_id_len = srpt_get_pr_transport_id_len, + .tpg_parse_pr_out_transport_id = srpt_parse_pr_out_transport_id, + .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_alloc_fabric_acl = srpt_alloc_fabric_acl, + .tpg_release_fabric_acl = srpt_release_fabric_acl, + .tpg_get_inst_index = srpt_tpg_get_inst_index, + .release_cmd = srpt_release_cmd, + .check_stop_free = srpt_check_stop_free, + .shutdown_session = srpt_shutdown_session, + .close_session = srpt_close_session, + .sess_get_index = srpt_sess_get_index, + .sess_get_initiator_sid = NULL, + .write_pending = srpt_write_pending, + .write_pending_status = srpt_write_pending_status, + .set_default_node_attributes = srpt_set_default_node_attrs, + .get_task_tag = srpt_get_task_tag, + .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_post_link = NULL, + .fabric_pre_unlink = NULL, + .fabric_make_np = NULL, + .fabric_drop_np = NULL, + .fabric_make_nodeacl = srpt_make_nodeacl, + .fabric_drop_nodeacl = srpt_drop_nodeacl, + + .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) +{ + ib_unregister_client(&srpt_client); + target_unregister_template(&srpt_template); +} + +module_init(srpt_init_module); +module_exit(srpt_cleanup_module); |