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2610bf1d0a0e396f0e6281f6c7d8c92d8fb1cfe2
scst/srpt/src/ib_srpt.c
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/*
* Copyright (c) 2006 - 2009 Mellanox Technology Inc. All rights reserved.
* Copyright (C) 2008 Vladislav Bolkhovitin <vst@vlnb.net>
* Copyright (C) 2008 - 2009 Bart Van Assche <bart.vanassche@gmail.com>
*
* 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/string.h>
#include <linux/kthread.h>
#include <linux/delay.h>
#include <asm/atomic.h>
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#endif
#include "ib_srpt.h"
#define LOG_PREFIX "ib_srpt" /* Prefix for SCST tracing macros. */
#include "scst_debug.h"
#define CONFIG_SCST_PROC
/* Name of this kernel module. */
#define DRV_NAME "ib_srpt"
#define DRV_VERSION "1.0.1"
#define DRV_RELDATE "July 10, 2008"
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
/* Flags to be used in SCST debug tracing statements. */
#define DEFAULT_SRPT_TRACE_FLAGS (TRACE_OUT_OF_MEM | TRACE_MINOR \
| TRACE_MGMT | TRACE_SPECIAL)
/* Name of the entry that will be created under /proc/scsi_tgt/ib_srpt. */
#define SRPT_PROC_TRACE_LEVEL_NAME "trace_level"
#endif
#define MELLANOX_SRPT_ID_STRING "SCST SRP target"
/* Similar to is_power_of_2(), but can be evaluated at compile time. */
#define IS_POWER_OF_2(n) ((n) != 0 && (((n) & ((n) - 1)) == 0))
MODULE_AUTHOR("Vu Pham");
MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol target "
"v" DRV_VERSION " (" DRV_RELDATE ")");
MODULE_LICENSE("Dual BSD/GPL");
struct srpt_thread {
/* Protects thread_ioctx_list. */
spinlock_t thread_lock;
/* I/O contexts to be processed by the kernel thread. */
struct list_head thread_ioctx_list;
/* SRPT kernel thread. */
struct task_struct *thread;
};
/*
* Global Variables
*/
static u64 srpt_service_guid;
/* List of srpt_device structures. */
static atomic_t srpt_device_count;
static int use_port_guid_in_session_name;
static int thread = 1;
static struct srpt_thread srpt_thread;
static DECLARE_WAIT_QUEUE_HEAD(ioctx_list_waitQ);
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
static unsigned long trace_flag = DEFAULT_SRPT_TRACE_FLAGS;
module_param(trace_flag, long, 0644);
MODULE_PARM_DESC(trace_flag,
"Trace flags for the ib_srpt kernel module.");
#endif
#if defined(CONFIG_SCST_DEBUG)
static unsigned long interrupt_processing_delay_in_us;
module_param(interrupt_processing_delay_in_us, long, 0744);
MODULE_PARM_DESC(interrupt_processing_delay_in_us,
"CQ completion handler interrupt delay in microseconds.");
static unsigned long thread_processing_delay_in_us;
module_param(thread_processing_delay_in_us, long, 0744);
MODULE_PARM_DESC(thread_processing_delay_in_us,
"SRP thread processing delay in microseconds.");
#endif
module_param(thread, int, 0444);
MODULE_PARM_DESC(thread,
"Executing ioctx in thread context. Default 0, i.e. soft IRQ, "
"where possible.");
static unsigned int srp_max_rdma_size = DEFAULT_MAX_RDMA_SIZE;
module_param(srp_max_rdma_size, int, 0744);
MODULE_PARM_DESC(thread,
"Maximum size of SRP RDMA transfers for new connections.");
static unsigned int srp_max_message_size = DEFAULT_MAX_MESSAGE_SIZE;
module_param(srp_max_message_size, int, 0444);
MODULE_PARM_DESC(thread,
"Maximum size of SRP control messages in bytes.");
module_param(use_port_guid_in_session_name, bool, 0444);
MODULE_PARM_DESC(use_port_guid_in_session_name,
"Use target port ID in the SCST session name such that"
" redundant paths between multiport systems can be masked.");
static void srpt_add_one(struct ib_device *device);
static void srpt_remove_one(struct ib_device *device);
static void srpt_unregister_mad_agent(struct srpt_device *sdev);
#ifdef CONFIG_SCST_PROC
static void srpt_unregister_procfs_entry(struct scst_tgt_template *tgt);
#endif /*CONFIG_SCST_PROC*/
static void srpt_unmap_sg_to_ib_sge(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx);
static void srpt_release_channel(struct scst_session *scst_sess);
static struct ib_client srpt_client = {
.name = DRV_NAME,
.add = srpt_add_one,
.remove = srpt_remove_one
};
/**
* Atomically test and set the channel state.
* @ch: RDMA channel.
* @old: channel state to compare with.
* @new: state to change the channel state to if the current state matches the
* argument 'old'.
*
* Returns the previous channel state.
*/
static enum rdma_ch_state
srpt_test_and_set_channel_state(struct srpt_rdma_ch *ch,
enum rdma_ch_state old,
enum rdma_ch_state new)
{
return atomic_cmpxchg(&ch->state, old, new);
}
/*
* 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;
TRACE_ENTRY();
sdev = ib_get_client_data(event->device, &srpt_client);
if (!sdev || sdev->device != event->device)
return;
TRACE_DBG("ASYNC event= %d on device= %s",
event->event, sdev->device->name);
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:
/*
* Refresh port data asynchronously. Note: it is safe to call
* schedule_work() even if &sport->work is already on the
* global workqueue because schedule_work() tests for the
* work_pending() condition before adding &sport->work to the
* global work queue.
*/
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:
PRINT_ERROR("received unrecognized IB event %d", event->event);
break;
}
TRACE_EXIT();
}
/*
* Callback function called by the InfiniBand core for SRQ (shared receive
* queue) events.
*/
static void srpt_srq_event(struct ib_event *event, void *ctx)
{
TRACE_ENTRY();
TRACE_DBG("SRQ event %d", event->event);
TRACE_EXIT();
}
/*
* Callback function called by the InfiniBand core for QP (queue pair) events.
*/
static void srpt_qp_event(struct ib_event *event, struct srpt_rdma_ch *ch)
{
TRACE_DBG("QP event %d on cm_id=%p sess_name=%s state=%d",
event->event, ch->cm_id, ch->sess_name,
atomic_read(&ch->state));
switch (event->event) {
case IB_EVENT_COMM_EST:
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20) || defined(BACKPORT_LINUX_WORKQUEUE_TO_2_6_19)
ib_cm_notify(ch->cm_id, event->event);
#else
/* Vanilla 2.6.19 kernel (or before) without OFED. */
PRINT_ERROR("%s", "how to perform ib_cm_notify() on a"
" vanilla 2.6.18 kernel ???");
#endif
break;
case IB_EVENT_QP_LAST_WQE_REACHED:
if (srpt_test_and_set_channel_state(ch, RDMA_CHANNEL_LIVE,
RDMA_CHANNEL_DISCONNECTING) == RDMA_CHANNEL_LIVE) {
PRINT_INFO("disconnected session %s.", ch->sess_name);
ib_send_cm_dreq(ch->cm_id, NULL, 0);
}
break;
default:
PRINT_ERROR("received unrecognized IB QP event %d",
event->event);
break;
}
}
/*
* Helper function for filling in an InfiniBand IOUnitInfo structure. 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.
*
* @pre 1 <= slot && 0 <= value && value < 16
*/
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;
}
}
/*
* Write InfiniBand ClassPortInfo to mad. 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;
}
/*
* Write IOUnitInfo to mad. See also section 16.3.3.3 IOUnitInfo in the
* InfiniBand Architecture Specification. See also section B.7,
* table B.6 in the T10 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 = 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;
}
/*
* Write IOControllerprofile to mad for I/O controller (sdev, slot). See also
* section 16.3.3.4 IOControllerProfile in the InfiniBand Architecture
* Specification. See also section B.7, table B.7 in the T10 SRP r16a
* document.
*/
static void srpt_get_ioc(struct srpt_device *sdev, u32 slot,
struct ib_dm_mad *mad)
{
struct ib_dm_ioc_profile *iocp;
iocp = (struct ib_dm_ioc_profile *)mad->data;
if (!slot || slot > 16) {
mad->mad_hdr.status = cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);
return;
}
if (slot > 2) {
mad->mad_hdr.status = cpu_to_be16(DM_MAD_STATUS_NO_IOC);
return;
}
memset(iocp, 0, sizeof *iocp);
strcpy(iocp->id_string, MELLANOX_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 = cpu_to_be16(SRP_REV16A_IB_IO_CLASS);
iocp->io_subclass = cpu_to_be16(SRP_IO_SUBCLASS);
iocp->protocol = cpu_to_be16(SRP_PROTOCOL);
iocp->protocol_version = cpu_to_be16(SRP_PROTOCOL_VERSION);
iocp->send_queue_depth = cpu_to_be16(SRPT_SRQ_SIZE);
iocp->rdma_read_depth = 4;
iocp->send_size = cpu_to_be32(srp_max_message_size);
iocp->rdma_size = cpu_to_be32(min(max(srp_max_rdma_size, 256U),
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;
}
/*
* Device management: write ServiceEntries to mad for the given slot. See also
* section 16.3.3.5 ServiceEntries in the InfiniBand Architecture
* Specification. See also section B.7, table B.8 in the T10 SRP r16a document.
*/
static void srpt_get_svc_entries(u64 ioc_guid,
u16 slot, u8 hi, u8 lo, struct ib_dm_mad *mad)
{
struct ib_dm_svc_entries *svc_entries;
WARN_ON(!ioc_guid);
if (!slot || slot > 16) {
mad->mad_hdr.status = cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);
return;
}
if (slot > 2 || lo > hi || hi > 1) {
mad->mad_hdr.status = cpu_to_be16(DM_MAD_STATUS_NO_IOC);
return;
}
svc_entries = (struct ib_dm_svc_entries *)mad->data;
memset(svc_entries, 0, sizeof *svc_entries);
svc_entries->service_entries[0].id = cpu_to_be64(ioc_guid);
snprintf(svc_entries->service_entries[0].name,
sizeof(svc_entries->service_entries[0].name),
"%s%016llx",
SRP_SERVICE_NAME_PREFIX,
(unsigned long long)ioc_guid);
mad->mad_hdr.status = 0;
}
/*
* Actual processing of a received MAD *rq_mad received through source port *sp
* (MAD = InfiniBand management datagram). The response to be sent back is
* written to *rsp_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->sdev, slot, rsp_mad);
break;
case DM_ATTR_SVC_ENTRIES:
slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod);
hi = (u8) ((slot >> 8) & 0xff);
lo = (u8) (slot & 0xff);
slot = (u16) ((slot >> 16) & 0xffff);
srpt_get_svc_entries(srpt_service_guid,
slot, hi, lo, rsp_mad);
break;
default:
rsp_mad->mad_hdr.status =
cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);
break;
}
}
/*
* Callback function that is called by the InfiniBand core after transmission of
* a MAD. (MAD = management datagram; AH = address handle.)
*/
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);
}
/*
* Callback function that is called by the InfiniBand core after reception of
* a MAD (management datagram).
*/
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 =
cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);
break;
default:
dm_mad->mad_hdr.status =
cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD);
break;
}
if (!ib_post_send_mad(rsp, NULL)) {
ib_free_recv_mad(mad_wc);
/* will destroy_ah & free_send_mad in send completion */
return;
}
ib_free_send_mad(rsp);
err_rsp:
ib_destroy_ah(ah);
err:
ib_free_recv_mad(mad_wc);
}
/*
* 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. 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;
TRACE_ENTRY();
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(&reg_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,
&reg_req, 0,
srpt_mad_send_handler,
srpt_mad_recv_handler,
sport);
if (IS_ERR(sport->mad_agent)) {
ret = PTR_ERR(sport->mad_agent);
sport->mad_agent = NULL;
goto err_query_port;
}
}
TRACE_EXIT_RES(0);
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:
TRACE_EXIT_RES(ret);
return ret;
}
/*
* Unregister the callback function for processing MADs and disable MAD
* processing for all ports of the specified device. 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)
PRINT_ERROR("%s", "disabling MAD processing failed.");
if (sport->mad_agent) {
ib_unregister_mad_agent(sport->mad_agent);
sport->mad_agent = NULL;
}
}
}
/**
* Allocate and initialize an SRPT I/O context structure.
*/
static struct srpt_ioctx *srpt_alloc_ioctx(struct srpt_device *sdev)
{
struct srpt_ioctx *ioctx;
ioctx = kmalloc(sizeof *ioctx, GFP_KERNEL);
if (!ioctx)
goto out;
ioctx->buf = kzalloc(srp_max_message_size, GFP_KERNEL);
if (!ioctx->buf)
goto out_free_ioctx;
ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf,
srp_max_message_size, DMA_BIDIRECTIONAL);
if (ib_dma_mapping_error(sdev->device, ioctx->dma))
goto out_free_buf;
return ioctx;
out_free_buf:
kfree(ioctx->buf);
out_free_ioctx:
kfree(ioctx);
out:
return NULL;
}
/*
* Deallocate an SRPT I/O context structure.
*/
static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx)
{
if (!ioctx)
return;
ib_dma_unmap_single(sdev->device, ioctx->dma,
srp_max_message_size, DMA_BIDIRECTIONAL);
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.
* @ioctx_ring: pointer to an array of I/O contexts.
* @ring_size: number of elements in the I/O context ring.
* @flags: flags to be set in the ring index.
*/
static int srpt_alloc_ioctx_ring(struct srpt_device *sdev,
struct srpt_ioctx **ioctx_ring,
int ring_size,
u32 flags)
{
int res;
int i;
TRACE_ENTRY();
res = -ENOMEM;
for (i = 0; i < ring_size; ++i) {
ioctx_ring[i] = srpt_alloc_ioctx(sdev);
if (!ioctx_ring[i])
goto err;
WARN_ON(i & flags);
ioctx_ring[i]->index = i | flags;
}
res = 0;
goto out;
err:
while (--i > 0) {
srpt_free_ioctx(sdev, ioctx_ring[i]);
ioctx_ring[i] = NULL;
}
out:
TRACE_EXIT_RES(res);
return res;
}
/* Free the ring of SRPT I/O context structures. */
static void srpt_free_ioctx_ring(struct srpt_device *sdev,
struct srpt_ioctx **ioctx_ring,
int ring_size)
{
int i;
for (i = 0; i < ring_size; ++i) {
srpt_free_ioctx(sdev, ioctx_ring[i]);
ioctx_ring[i] = NULL;
}
}
/**
* Set the state of a command.
* @new: New state to be set.
*
* Does not modify the state of aborted commands. Returns the previous command
* state.
*/
static enum srpt_command_state srpt_set_cmd_state(struct srpt_ioctx *ioctx,
enum srpt_command_state new)
{
enum srpt_command_state previous;
WARN_ON(!ioctx);
WARN_ON(new == SRPT_STATE_NEW);
do {
previous = atomic_read(&ioctx->state);
} while (previous != SRPT_STATE_ABORTED
&& atomic_cmpxchg(&ioctx->state, previous, new) != previous);
return previous;
}
/**
* Test and set the state of a command.
* @old: State to compare against.
* @new: New state to be set if the current state matches 'old'.
*
* Returns the previous command state.
*/
static enum srpt_command_state
srpt_test_and_set_cmd_state(struct srpt_ioctx *ioctx,
enum srpt_command_state old,
enum srpt_command_state new)
{
WARN_ON(!ioctx);
WARN_ON(old == SRPT_STATE_ABORTED);
WARN_ON(new == SRPT_STATE_NEW);
return atomic_cmpxchg(&ioctx->state, old, new);
}
/**
* Post a receive request on the work queue of InfiniBand device 'sdev'.
*/
static int srpt_post_recv(struct srpt_device *sdev, struct srpt_ioctx *ioctx)
{
struct ib_sge list;
struct ib_recv_wr wr, *bad_wr;
wr.wr_id = ioctx->index | SRPT_OP_RECV;
list.addr = ioctx->dma;
list.length = srp_max_message_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);
}
/**
* Post an IB send request.
* @ch: RDMA channel to post the send request on.
* @ioctx: I/O context of the send request.
* @len: length of the request to be sent in bytes.
*
* Returns zero upon success and a non-zero value upon failure.
*/
static int srpt_post_send(struct srpt_rdma_ch *ch, struct srpt_ioctx *ioctx,
int len)
{
struct ib_sge list;
struct ib_send_wr wr, *bad_wr;
struct srpt_device *sdev = ch->sport->sdev;
int ret;
ret = -ENOMEM;
if (atomic_dec_return(&ch->qp_wr_avail) < 0) {
PRINT_ERROR("%s[%d]: SRQ full", __func__, __LINE__);
goto out;
}
ib_dma_sync_single_for_device(sdev->device, ioctx->dma,
len, DMA_TO_DEVICE);
list.addr = ioctx->dma;
list.length = len;
list.lkey = sdev->mr->lkey;
wr.next = NULL;
wr.wr_id = 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->qp_wr_avail);
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_ioctx *ioctx, struct srp_cmd *srp_cmd,
scst_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.
*/
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 31)
BUILD_BUG_ON(!__same_type(srp_cmd->add_data[0], (s8)0)
&& !__same_type(srp_cmd->add_data[0], (u8)0));
#else
/* Note: the __same_type() macro has been introduced in kernel 2.6.31.*/
#endif
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 = SCST_DATA_NONE;
if (srp_cmd->buf_fmt & 0xf)
/* DATA-IN: transfer data from target to initiator. */
*dir = SCST_DATA_READ;
else if (srp_cmd->buf_fmt >> 4)
/* DATA-OUT: transfer data from initiator to target. */
*dir = SCST_DATA_WRITE;
/*
* 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)) {
PRINT_ERROR("received corrupt SRP_CMD request"
" (%u out + %u in != %u / %zu)",
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;
}
/*
* Modify the attributes of queue pair 'qp': allow local write, remote read,
* and remote write. Also transition '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;
}
/**
* 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;
}
/**
* 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;
}
/* Obtain an I/O context for sending a request to the initiator. */
static struct srpt_ioctx *srpt_get_req_ioctx(struct srpt_rdma_ch *ch)
{
int tail;
BUG_ON(!ch);
BUILD_BUG_ON(!IS_POWER_OF_2(REQ_IOCTX_COUNT));
tail = atomic_inc_return(&ch->req_ioctx_tail) - 1;
if (tail - atomic_read(&ch->req_ioctx_head) >= REQ_IOCTX_COUNT) {
atomic_dec(&ch->req_ioctx_tail);
return NULL;
}
return ch->req_ioctx_ring[tail & (REQ_IOCTX_COUNT - 1)];
}
/*
* Put back an I/O context that has been used for sending a request to the
* initiator.
*/
static void srpt_put_req_ioctx(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx)
{
int head;
BUG_ON(!ch);
BUILD_BUG_ON(!IS_POWER_OF_2(REQ_IOCTX_COUNT));
head = atomic_inc_return(&ch->req_ioctx_head);
}
/**
* srpt_req_lim_delta() - Compute by how much req_lim changed since the
* last time this function has been called. This value is necessary for
* filling in the REQUEST LIMIT DELTA field of an SRP_RSP response.
*
* Side Effect: Modifies ch->last_response_req_lim.
*/
static int srpt_req_lim_delta(struct srpt_rdma_ch *ch)
{
int req_lim;
int req_lim_delta;
req_lim = atomic_read(&ch->req_lim);
if (req_lim <= 1)
atomic_set(&ch->send_cred_req, 1);
req_lim_delta = req_lim - atomic_read(&ch->last_response_req_lim);
atomic_add(req_lim_delta, &ch->last_response_req_lim);
return req_lim_delta;
}
/* Send an SRP_CRED_REQ information unit to the initiator. */
static int srpt_send_cred_req(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx,
s32 req_lim_delta)
{
struct srp_cred_req *srp_cred_req;
BUG_ON(!ch);
srp_cred_req = ioctx->buf;
BUG_ON(!srp_cred_req);
memset(srp_cred_req, 0, sizeof(*srp_cred_req));
srp_cred_req->opcode = SRP_CRED_REQ;
srp_cred_req->sol_not = ch->crsolnt ? SRP_SOLNT : 0;
srp_cred_req->req_lim_delta = cpu_to_be32(req_lim_delta);
srp_cred_req->tag = cpu_to_be64(ch->cred_req_tag++);
return srpt_post_send(ch, ioctx, sizeof(*srp_cred_req));
}
static void srpt_alloc_and_send_cred_req(struct srpt_rdma_ch *ch)
{
s32 req_lim_delta;
req_lim_delta = srpt_req_lim_delta(ch);
if (req_lim_delta) {
struct srpt_ioctx *ioctx;
int res;
ioctx = srpt_get_req_ioctx(ch);
if (ioctx) {
res = srpt_send_cred_req(ch, ioctx,
req_lim_delta);
if (res == 0) {
PRINT_INFO("Sent SRP_CRED_REQ"
" with req_lim_delta"
" = %d and tag %lld",
req_lim_delta,
ch->cred_req_tag);
} else {
PRINT_ERROR("sending SRP_CRED_REQ"
" failed (res = %d)", res);
goto err;
}
} else {
PRINT_ERROR("%s",
"Sending SRP_CRED_REQ failed -- no I/O context"
" available ! Does the initiator have SRP_CRED_REQ"
" support ? This will sooner or later result in"
" an initiator lockup.");
goto err;
}
}
return;
err:
atomic_sub(req_lim_delta, &ch->last_response_req_lim);
return;
}
static void srpt_reset_ioctx(struct srpt_rdma_ch *ch, struct srpt_ioctx *ioctx)
{
srpt_unmap_sg_to_ib_sge(ch, ioctx);
if (ioctx->n_rbuf > 1) {
kfree(ioctx->rbufs);
ioctx->rbufs = NULL;
}
WARN_ON(!ch);
if (!ch)
return;
if (srpt_post_recv(ch->sport->sdev, ioctx))
PRINT_ERROR("%s", "SRQ post_recv failed - this is serious.");
/* we should queue it back to free_ioctx queue */
else {
int req_lim;
req_lim = atomic_inc_return(&ch->req_lim);
if (req_lim < 0 || req_lim > SRPT_RQ_SIZE)
PRINT_ERROR("internal error: req_lim = %d out of range"
"%d .. %d", req_lim, 0, SRPT_RQ_SIZE);
if (req_lim == SRPT_RQ_SIZE / 2
&& atomic_xchg(&ch->send_cred_req, 0))
srpt_alloc_and_send_cred_req(ch);
}
}
/**
* Abort a command.
*/
static void srpt_abort_scst_cmd(struct srpt_device *sdev,
struct scst_cmd *scmnd)
{
struct srpt_ioctx *ioctx;
scst_data_direction dir;
enum srpt_command_state previous_state;
TRACE_ENTRY();
ioctx = scst_cmd_get_tgt_priv(scmnd);
BUG_ON(!ioctx);
previous_state = srpt_set_cmd_state(ioctx, SRPT_STATE_ABORTED);
if (previous_state == SRPT_STATE_ABORTED)
goto out;
TRACE_DBG("Aborting cmd with state %d and tag %lld",
previous_state, scst_cmd_get_tag(scmnd));
dir = scst_cmd_get_data_direction(scmnd);
if (dir != SCST_DATA_NONE && scst_cmd_get_sg(scmnd))
ib_dma_unmap_sg(sdev->device,
scst_cmd_get_sg(scmnd),
scst_cmd_get_sg_cnt(scmnd),
scst_to_tgt_dma_dir(dir));
switch (previous_state) {
case SRPT_STATE_NEW:
scst_set_delivery_status(scmnd, SCST_CMD_DELIVERY_ABORTED);
break;
case SRPT_STATE_NEED_DATA:
WARN_ON(scst_cmd_get_data_direction(ioctx->scmnd)
== SCST_DATA_READ);
scst_rx_data(scmnd, SCST_RX_STATUS_ERROR,
scst_estimate_context());
break;
case SRPT_STATE_DATA_IN:
case SRPT_STATE_PROCESSED:
scst_set_delivery_status(scmnd, SCST_CMD_DELIVERY_ABORTED);
break;
default:
TRACE_DBG("Aborting cmd with state %d", previous_state);
WARN_ON("ERROR: unexpected command state");
}
scst_tgt_cmd_done(scmnd, scst_estimate_context());
out:
;
TRACE_EXIT();
}
static void srpt_handle_err_comp(struct srpt_rdma_ch *ch, struct ib_wc *wc)
{
struct srpt_ioctx *ioctx;
struct srpt_device *sdev = ch->sport->sdev;
if (wc->wr_id & SRPT_OP_RECV) {
ioctx = sdev->ioctx_ring[wc->wr_id & ~SRPT_OP_RECV];
PRINT_ERROR("%s", "This is serious - SRQ is in bad state.");
} else if (wc->wr_id & SRPT_OP_TXR) {
PRINT_ERROR("%s", "sending request failed");
ioctx = ch->req_ioctx_ring[wc->wr_id & ~SRPT_OP_TXR];
srpt_put_req_ioctx(ch, ioctx);
} else {
ioctx = sdev->ioctx_ring[wc->wr_id];
if (ioctx->scmnd)
srpt_abort_scst_cmd(sdev, ioctx->scmnd);
else
srpt_reset_ioctx(ch, ioctx);
}
}
/** Process an IB send completion notification. */
static void srpt_handle_send_comp(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx,
enum scst_exec_context context)
{
if (ioctx->scmnd) {
scst_data_direction dir =
scst_cmd_get_data_direction(ioctx->scmnd);
if (dir != SCST_DATA_NONE && scst_cmd_get_sg(ioctx->scmnd))
ib_dma_unmap_sg(ch->sport->sdev->device,
scst_cmd_get_sg(ioctx->scmnd),
scst_cmd_get_sg_cnt(ioctx->scmnd),
scst_to_tgt_dma_dir(dir));
scst_tgt_cmd_done(ioctx->scmnd, context);
} else
srpt_reset_ioctx(ch, ioctx);
}
/** Process an IB RDMA completion notification. */
static void srpt_handle_rdma_comp(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx)
{
if (!ioctx->scmnd) {
WARN_ON("ERROR: ioctx->scmnd == NULL");
srpt_reset_ioctx(ch, ioctx);
return;
}
/*
* If an RDMA completion notification has been received for a write
* command, tell SCST that processing can continue by calling
* scst_rx_data().
*/
if (srpt_test_and_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA,
SRPT_STATE_DATA_IN) == SRPT_STATE_NEED_DATA) {
WARN_ON(scst_cmd_get_data_direction(ioctx->scmnd)
== SCST_DATA_READ);
scst_rx_data(ioctx->scmnd, SCST_RX_STATUS_SUCCESS,
scst_estimate_context());
}
}
/**
* 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.
* @sense_data: pointer to sense data to be included in the response.
* @sense_data_len: length in bytes of the sense data.
*
* 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 T10 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_ioctx *ioctx, s32 req_lim_delta,
u64 tag, int status,
const u8 *sense_data, int sense_data_len)
{
struct srp_rsp *srp_rsp;
int 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->buf;
BUG_ON(!srp_rsp);
memset(srp_rsp, 0, sizeof *srp_rsp);
srp_rsp->opcode = SRP_RSP;
/*
* Copy the SCSOLNT or UCSOLNT bit from the request to the SOLNT bit
* of the response.
*/
srp_rsp->sol_not
= (ioctx->sol_not
& (status == SAM_STAT_GOOD ? SRP_SCSOLNT : SRP_UCSOLNT))
? SRP_SOLNT : 0;
srp_rsp->req_lim_delta = cpu_to_be32(req_lim_delta);
srp_rsp->tag = tag;
if (SCST_SENSE_VALID(sense_data)) {
BUILD_BUG_ON(MIN_MAX_MESSAGE_SIZE <= sizeof(*srp_rsp));
max_sense_len = ch->max_ti_iu_len - sizeof(*srp_rsp);
if (sense_data_len > max_sense_len) {
PRINT_WARNING("truncated sense data from %d to %d"
" bytes", sense_data_len,
max_sense_len);
sense_data_len = max_sense_len;
}
srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID;
srp_rsp->status = status;
srp_rsp->sense_data_len = cpu_to_be32(sense_data_len);
memcpy(srp_rsp + 1, sense_data, sense_data_len);
} else
sense_data_len = 0;
#if 0
printk(KERN_DEBUG "SRP response:\n");
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 1, srp_rsp,
sizeof(*srp_rsp) + sense_data_len, 1);
#endif
return sizeof(*srp_rsp) + sense_data_len;
}
/**
* Build a task management response, which is a specific SRP_RSP 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 T10 SRP r16a document for the format of an SRP_RSP
* response.
*/
static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx, s32 req_lim_delta,
u8 rsp_code, u64 tag)
{
struct srp_rsp *srp_rsp;
int resp_data_len;
int resp_len;
resp_data_len = (rsp_code == SRP_TSK_MGMT_SUCCESS) ? 0 : 4;
resp_len = sizeof(*srp_rsp) + resp_data_len;
srp_rsp = ioctx->buf;
memset(srp_rsp, 0, sizeof *srp_rsp);
srp_rsp->opcode = SRP_RSP;
/*
* Copy the SCSOLNT or UCSOLNT bit from the request to the SOLNT bit
* of the response.
*/
srp_rsp->sol_not
= (ioctx->sol_not
& (rsp_code == SRP_TSK_MGMT_SUCCESS
? SRP_SCSOLNT : SRP_UCSOLNT))
? SRP_SOLNT : 0;
srp_rsp->req_lim_delta = cpu_to_be32(req_lim_delta);
srp_rsp->tag = tag;
if (rsp_code != SRP_TSK_MGMT_SUCCESS) {
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;
}
/*
* Process SRP_CMD.
*/
static int srpt_handle_cmd(struct srpt_rdma_ch *ch, struct srpt_ioctx *ioctx)
{
struct scst_cmd *scmnd;
struct srp_cmd *srp_cmd;
scst_data_direction dir;
u64 data_len;
int ret;
srp_cmd = ioctx->buf;
scmnd = scst_rx_cmd(ch->scst_sess, (u8 *) &srp_cmd->lun,
sizeof srp_cmd->lun, srp_cmd->cdb, 16,
thread ? SCST_NON_ATOMIC : SCST_ATOMIC);
if (!scmnd)
goto err;
ioctx->scmnd = scmnd;
ret = srpt_get_desc_tbl(ioctx, srp_cmd, &dir, &data_len);
if (ret) {
scst_set_cmd_error(scmnd,
SCST_LOAD_SENSE(scst_sense_invalid_field_in_cdb));
goto err;
}
switch (srp_cmd->task_attr) {
case SRP_CMD_HEAD_OF_Q:
scmnd->queue_type = SCST_CMD_QUEUE_HEAD_OF_QUEUE;
break;
case SRP_CMD_ORDERED_Q:
scmnd->queue_type = SCST_CMD_QUEUE_ORDERED;
break;
case SRP_CMD_SIMPLE_Q:
scmnd->queue_type = SCST_CMD_QUEUE_SIMPLE;
break;
case SRP_CMD_ACA:
scmnd->queue_type = SCST_CMD_QUEUE_ACA;
break;
default:
scmnd->queue_type = SCST_CMD_QUEUE_ORDERED;
break;
}
scst_cmd_set_tag(scmnd, srp_cmd->tag);
scst_cmd_set_tgt_priv(scmnd, ioctx);
scst_cmd_set_expected(scmnd, dir, data_len);
scst_cmd_init_done(scmnd, scst_estimate_context());
return 0;
err:
return -1;
}
/*
* srpt_handle_tsk_mgmt() - Process an SRP_TSK_MGMT information unit.
*
* Returns SRP_TSK_MGMT_SUCCESS upon success.
*
* Each task management function is performed by calling one of the
* scst_rx_mgmt_fn*() functions. These functions will either report failure
* or process the task management function asynchronously. The function
* srpt_tsk_mgmt_done() will be called by the SCST core upon completion of the
* task management function. When srpt_handle_tsk_mgmt() reports failure
* (i.e. returns -1) a response will have been built in ioctx->buf. This
* information unit has to be sent back by the caller.
*
* For more information about SRP_TSK_MGMT information units, see also section
* 6.7 in the T10 SRP r16a document.
*/
static u8 srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx)
{
struct srp_tsk_mgmt *srp_tsk;
struct srpt_mgmt_ioctx *mgmt_ioctx;
int ret;
u8 srp_tsk_mgmt_status;
srp_tsk = ioctx->buf;
TRACE_DBG("recv_tsk_mgmt= %d for task_tag= %lld"
" using tag= %lld cm_id= %p sess= %p",
srp_tsk->tsk_mgmt_func,
(unsigned long long) srp_tsk->task_tag,
(unsigned long long) srp_tsk->tag,
ch->cm_id, ch->scst_sess);
srp_tsk_mgmt_status = SRP_TSK_MGMT_FAILED;
mgmt_ioctx = kmalloc(sizeof *mgmt_ioctx, GFP_ATOMIC);
if (!mgmt_ioctx)
goto err;
mgmt_ioctx->ioctx = ioctx;
mgmt_ioctx->ch = ch;
mgmt_ioctx->tag = srp_tsk->tag;
switch (srp_tsk->tsk_mgmt_func) {
case SRP_TSK_ABORT_TASK:
TRACE_DBG("%s", "Processing SRP_TSK_ABORT_TASK");
ret = scst_rx_mgmt_fn_tag(ch->scst_sess,
SCST_ABORT_TASK,
srp_tsk->task_tag,
thread ?
SCST_NON_ATOMIC : SCST_ATOMIC,
mgmt_ioctx);
break;
case SRP_TSK_ABORT_TASK_SET:
TRACE_DBG("%s", "Processing SRP_TSK_ABORT_TASK_SET");
ret = scst_rx_mgmt_fn_lun(ch->scst_sess,
SCST_ABORT_TASK_SET,
(u8 *) &srp_tsk->lun,
sizeof srp_tsk->lun,
thread ?
SCST_NON_ATOMIC : SCST_ATOMIC,
mgmt_ioctx);
break;
case SRP_TSK_CLEAR_TASK_SET:
TRACE_DBG("%s", "Processing SRP_TSK_CLEAR_TASK_SET");
ret = scst_rx_mgmt_fn_lun(ch->scst_sess,
SCST_CLEAR_TASK_SET,
(u8 *) &srp_tsk->lun,
sizeof srp_tsk->lun,
thread ?
SCST_NON_ATOMIC : SCST_ATOMIC,
mgmt_ioctx);
break;
case SRP_TSK_LUN_RESET:
TRACE_DBG("%s", "Processing SRP_TSK_LUN_RESET");
ret = scst_rx_mgmt_fn_lun(ch->scst_sess,
SCST_LUN_RESET,
(u8 *) &srp_tsk->lun,
sizeof srp_tsk->lun,
thread ?
SCST_NON_ATOMIC : SCST_ATOMIC,
mgmt_ioctx);
break;
case SRP_TSK_CLEAR_ACA:
TRACE_DBG("%s", "Processing SRP_TSK_CLEAR_ACA");
ret = scst_rx_mgmt_fn_lun(ch->scst_sess,
SCST_CLEAR_ACA,
(u8 *) &srp_tsk->lun,
sizeof srp_tsk->lun,
thread ?
SCST_NON_ATOMIC : SCST_ATOMIC,
mgmt_ioctx);
break;
default:
TRACE_DBG("%s", "Unsupported task management function.");
srp_tsk_mgmt_status = SRP_TSK_MGMT_FUNC_NOT_SUPP;
goto err;
}
if (ret) {
TRACE_DBG("Processing task management function failed"
" (ret = %d).", ret);
goto err;
}
return SRP_TSK_MGMT_SUCCESS;
err:
kfree(mgmt_ioctx);
return srp_tsk_mgmt_status;
}
/**
* 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_ioctx *ioctx)
{
struct srp_cmd *srp_cmd;
enum rdma_ch_state ch_state;
u8 srp_response_status;
u8 srp_tsk_mgmt_status;
int len;
/*
* A quote from SAM-3, paragraph 4.9.6: "Any command that is not
* relayed to a dependent logical unit shall be terminated with a
* CHECK CONDITION status. The sense key shall be set to ILLEGAL
* REQUEST and the additional sense code shall be set to INVALID
* COMMAND OPERATION CODE. If a task management function cannot be
* relayed to a dependent logical unit, a service response of SERVICE
* DELIVERY OR TARGET FAILURE shall be returned."
*/
srp_response_status = SAM_STAT_BUSY;
/* To keep the compiler happy. */
srp_tsk_mgmt_status = -1;
ch_state = atomic_read(&ch->state);
if (ch_state == RDMA_CHANNEL_CONNECTING) {
list_add_tail(&ioctx->wait_list, &ch->cmd_wait_list);
return;
} else if (ch_state == RDMA_CHANNEL_DISCONNECTING) {
srpt_reset_ioctx(ch, ioctx);
return;
}
WARN_ON(ch_state != RDMA_CHANNEL_LIVE);
ib_dma_sync_single_for_cpu(ch->sport->sdev->device,
ioctx->dma, srp_max_message_size,
DMA_FROM_DEVICE);
srp_cmd = ioctx->buf;
ioctx->n_rbuf = 0;
ioctx->rbufs = NULL;
ioctx->n_rdma = 0;
ioctx->n_rdma_ius = 0;
ioctx->rdma_ius = NULL;
ioctx->scmnd = NULL;
ioctx->ch = ch;
ioctx->sol_not = srp_cmd->sol_not;
atomic_set(&ioctx->state, SRPT_STATE_NEW);
switch (srp_cmd->opcode) {
case SRP_CMD:
if (srpt_handle_cmd(ch, ioctx) < 0) {
if (ioctx->scmnd)
srp_response_status =
scst_cmd_get_status(ioctx->scmnd);
goto err;
}
break;
case SRP_TSK_MGMT:
srp_tsk_mgmt_status = srpt_handle_tsk_mgmt(ch, ioctx);
if (srp_tsk_mgmt_status != SRP_TSK_MGMT_SUCCESS)
goto err;
break;
case SRP_CRED_RSP:
TRACE_DBG("%s", "received SRP_CRED_RSP");
srpt_reset_ioctx(ch, ioctx);
break;
case SRP_AER_RSP:
TRACE_DBG("%s", "received SRP_AER_RSP");
srpt_reset_ioctx(ch, ioctx);
break;
case SRP_I_LOGOUT:
default:
goto err;
}
return;
err:
ch_state = atomic_read(&ch->state);
if (ch_state != RDMA_CHANNEL_LIVE) {
/* Give up if another thread modified the channel state. */
PRINT_ERROR("%s: channel is in state %d", __func__, ch_state);
srpt_reset_ioctx(ch, ioctx);
} else {
s32 req_lim_delta;
req_lim_delta = srpt_req_lim_delta(ch) + 1;
if (srp_cmd->opcode == SRP_TSK_MGMT) {
len = srpt_build_tskmgmt_rsp(ch, ioctx, req_lim_delta,
srp_tsk_mgmt_status,
((struct srp_tsk_mgmt *)srp_cmd)->tag);
} else if (ioctx->scmnd)
len = srpt_build_cmd_rsp(ch, ioctx, req_lim_delta,
srp_cmd->tag, srp_response_status,
scst_cmd_get_sense_buffer(ioctx->scmnd),
scst_cmd_get_sense_buffer_len(ioctx->scmnd));
else {
len = srpt_build_cmd_rsp(ch, ioctx, srp_cmd->tag,
req_lim_delta,
srp_response_status,
NULL, 0);
}
if (srpt_post_send(ch, ioctx, len)) {
PRINT_ERROR("%s", "Sending SRP_RSP response failed.");
atomic_sub(req_lim_delta, &ch->last_response_req_lim);
srpt_reset_ioctx(ch, ioctx);
}
}
}
/*
* Returns true if the ioctx list is non-empty or if the ib_srpt kernel thread
* should stop.
* @pre thread != 0
*/
static inline int srpt_test_ioctx_list(void)
{
int res = (!list_empty(&srpt_thread.thread_ioctx_list) ||
unlikely(kthread_should_stop()));
return res;
}
/*
* Add 'ioctx' to the tail of the ioctx list and wake up the kernel thread.
*
* @pre thread != 0
*/
static inline void srpt_schedule_thread(struct srpt_ioctx *ioctx)
{
unsigned long flags;
spin_lock_irqsave(&srpt_thread.thread_lock, flags);
list_add_tail(&ioctx->comp_list, &srpt_thread.thread_ioctx_list);
spin_unlock_irqrestore(&srpt_thread.thread_lock, flags);
wake_up(&ioctx_list_waitQ);
}
/**
* InfiniBand completion queue callback function.
* @cq: completion queue.
* @ctx: completion queue context, which was passed as the fourth argument of
* the function ib_create_cq().
*/
static void srpt_completion(struct ib_cq *cq, void *ctx)
{
struct srpt_rdma_ch *ch = ctx;
struct srpt_device *sdev = ch->sport->sdev;
struct ib_wc wc;
struct srpt_ioctx *ioctx;
ib_req_notify_cq(ch->cq, IB_CQ_NEXT_COMP);
while (ib_poll_cq(ch->cq, 1, &wc) > 0) {
if (wc.status) {
PRINT_INFO("%s failed with status %d",
wc.wr_id & SRPT_OP_RECV
? "receiving"
: wc.wr_id & SRPT_OP_TXR
? "sending request"
: "sending response",
wc.status);
srpt_handle_err_comp(ch, &wc);
continue;
}
if (wc.wr_id & SRPT_OP_RECV) {
int req_lim;
req_lim = atomic_dec_return(&ch->req_lim);
if (req_lim < 0)
PRINT_ERROR("internal error: req_lim = %d < 0",
req_lim);
ioctx = sdev->ioctx_ring[wc.wr_id & ~SRPT_OP_RECV];
if (thread) {
ioctx->ch = ch;
ioctx->op = IB_WC_RECV;
srpt_schedule_thread(ioctx);
} else
srpt_handle_new_iu(ch, ioctx);
} else if (wc.wr_id & SRPT_OP_TXR) {
TRACE_DBG("received completion for request %llu",
wc.wr_id & ~SRPT_OP_TXR);
ioctx = ch->req_ioctx_ring[wc.wr_id & ~SRPT_OP_TXR];
srpt_put_req_ioctx(ch, ioctx);
} else {
ioctx = sdev->ioctx_ring[wc.wr_id];
if (wc.opcode == IB_WC_SEND)
atomic_inc(&ch->qp_wr_avail);
else {
WARN_ON(wc.opcode != IB_WC_RDMA_READ);
WARN_ON(ioctx->n_rdma <= 0);
atomic_add(ioctx->n_rdma,
&ch->qp_wr_avail);
}
if (thread) {
ioctx->ch = ch;
ioctx->op = wc.opcode;
srpt_schedule_thread(ioctx);
} else {
switch (wc.opcode) {
case IB_WC_SEND:
srpt_handle_send_comp(ch, ioctx,
scst_estimate_context());
break;
case IB_WC_RDMA_WRITE:
case IB_WC_RDMA_READ:
srpt_handle_rdma_comp(ch, ioctx);
break;
default:
PRINT_ERROR("received unrecognized"
" IB WC opcode %d",
wc.opcode);
break;
}
}
}
#if defined(CONFIG_SCST_DEBUG)
if (interrupt_processing_delay_in_us <= MAX_UDELAY_MS * 1000)
udelay(interrupt_processing_delay_in_us);
#endif
}
}
/*
* Create a completion queue on the specified device.
*/
static int srpt_create_ch_ib(struct srpt_rdma_ch *ch)
{
struct ib_qp_init_attr *qp_init;
struct srpt_device *sdev = ch->sport->sdev;
int cqe;
int ret;
qp_init = kzalloc(sizeof *qp_init, GFP_KERNEL);
if (!qp_init)
return -ENOMEM;
/* Create a completion queue (CQ). */
cqe = SRPT_RQ_SIZE + SRPT_SQ_SIZE - 1;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20) && ! defined(RHEL_RELEASE_CODE)
ch->cq = ib_create_cq(sdev->device, srpt_completion, NULL, ch, cqe);
#else
ch->cq = ib_create_cq(sdev->device, srpt_completion, NULL, ch, cqe, 0);
#endif
if (IS_ERR(ch->cq)) {
ret = PTR_ERR(ch->cq);
PRINT_ERROR("failed to create_cq cqe= %d ret= %d", cqe, ret);
goto out;
}
/* Request completion notification. */
ib_req_notify_cq(ch->cq, IB_CQ_NEXT_COMP);
/* Create a queue pair (QP). */
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 = SRPT_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);
ib_destroy_cq(ch->cq);
PRINT_ERROR("failed to create_qp ret= %d", ret);
goto out;
}
atomic_set(&ch->qp_wr_avail, qp_init->cap.max_send_wr);
TRACE_DBG("%s: max_cqe= %d max_sge= %d cm_id= %p",
__func__, ch->cq->cqe, qp_init->cap.max_send_sge,
ch->cm_id);
/* Modify the attributes and the state of queue pair ch->qp. */
ret = srpt_init_ch_qp(ch, ch->qp);
if (ret) {
ib_destroy_qp(ch->qp);
ib_destroy_cq(ch->cq);
goto out;
}
out:
kfree(qp_init);
return ret;
}
/**
* Release the channel corresponding to the specified cm_id.
*
* 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 SCST sessions for the associated
* IB device have been unregistered and SCST 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_release_channel_by_cmid(struct ib_cm_id *cm_id)
{
struct srpt_device *sdev;
struct srpt_rdma_ch *ch;
bool found;
TRACE_ENTRY();
sdev = cm_id->context;
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) {
list_del(&ch->list);
atomic_set(&ch->state, RDMA_CHANNEL_DISCONNECTING);
found = true;
break;
}
}
spin_unlock_irq(&sdev->spinlock);
if (found)
scst_unregister_session(ch->scst_sess, 0, srpt_release_channel);
TRACE_EXIT();
}
/**
* Look up the RDMA channel that corresponds to the specified cm_id.
*
* 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;
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_alloc_req_ring() - Allocate a ring of SRP I/O contexts and set
* the SRPT_OP_TXR flag in the index of each I/O context.
*/
static int srpt_alloc_req_ring(struct srpt_rdma_ch *ch)
{
int res;
BUG_ON(!ch);
BUG_ON(!ch->sport);
BUG_ON(!ch->sport->sdev);
atomic_set(&ch->req_ioctx_head, 0);
atomic_set(&ch->req_ioctx_tail, 0);
res = srpt_alloc_ioctx_ring(ch->sport->sdev, ch->req_ioctx_ring,
ARRAY_SIZE(ch->req_ioctx_ring),
SRPT_OP_TXR);
return res;
}
static void srpt_free_req_ring(struct srpt_rdma_ch *ch)
{
BUG_ON(!ch);
BUG_ON(!ch->sport);
BUG_ON(!ch->sport->sdev);
srpt_free_ioctx_ring(ch->sport->sdev, ch->req_ioctx_ring,
ARRAY_SIZE(ch->req_ioctx_ring));
}
/**
* Release all resources associated with an RDMA channel.
*
* Notes:
* - The caller must have removed the channel from the channel list before
* calling this function.
* - Must be called as a callback function via scst_unregister_session(). Never
* call this function directly because doing so would trigger several race
* conditions.
* - Do not access ch->sport or ch->sport->sdev in this function because the
* memory that was allocated for the sport and/or sdev data structures may
* already have been freed at the time this function is called.
*/
static void srpt_release_channel(struct scst_session *scst_sess)
{
struct srpt_rdma_ch *ch;
TRACE_ENTRY();
ch = scst_sess_get_tgt_priv(scst_sess);
BUG_ON(!ch);
WARN_ON(atomic_read(&ch->state) != RDMA_CHANNEL_DISCONNECTING);
TRACE_DBG("destroying cm_id %p", ch->cm_id);
BUG_ON(!ch->cm_id);
ib_destroy_cm_id(ch->cm_id);
ib_destroy_qp(ch->qp);
ib_destroy_cq(ch->cq);
srpt_free_req_ring(ch);
kfree(ch);
TRACE_EXIT();
}
/**
* Process the event IB_CM_REQ_RECEIVED.
*
* Ownership of the cm_id is transferred to the SCST 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 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;
u32 it_iu_len;
int ret = 0;
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
WARN_ON(!sdev || !private_data);
if (!sdev || !private_data)
return -EINVAL;
#else
if (WARN_ON(!sdev || !private_data))
return -EINVAL;
#endif
req = (struct srp_login_req *)private_data;
it_iu_len = be32_to_cpu(req->req_it_iu_len);
PRINT_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)",
(unsigned long long)be64_to_cpu(*(u64 *)&req->initiator_port_id[0]),
(unsigned long long)be64_to_cpu(*(u64 *)&req->initiator_port_id[8]),
(unsigned long long)be64_to_cpu(*(u64 *)&req->target_port_id[0]),
(unsigned long long)be64_to_cpu(*(u64 *)&req->target_port_id[8]),
it_iu_len,
param->port,
(unsigned long long)be64_to_cpu(*(u64 *)
&sdev->port[param->port - 1].gid.raw[0]),
(unsigned long long)be64_to_cpu(*(u64 *)
&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_message_size || it_iu_len < 64) {
rej->reason =
cpu_to_be32(SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE);
ret = -EINVAL;
PRINT_ERROR("rejected SRP_LOGIN_REQ because its"
" length (%d bytes) is out of range (%d .. %d)",
it_iu_len, 64, srp_max_message_size);
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 prev_state;
/* found an existing channel */
TRACE_DBG("Found existing channel name= %s"
" cm_id= %p state= %d",
ch->sess_name, ch->cm_id,
atomic_read(&ch->state));
prev_state = atomic_xchg(&ch->state,
RDMA_CHANNEL_DISCONNECTING);
if (prev_state == RDMA_CHANNEL_CONNECTING)
list_del(&ch->list);
spin_unlock_irq(&sdev->spinlock);
rsp->rsp_flags =
SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
if (prev_state == RDMA_CHANNEL_LIVE) {
ib_send_cm_dreq(ch->cm_id, NULL, 0);
PRINT_INFO("disconnected"
" session %s because a new"
" SRP_LOGIN_REQ has been received.",
ch->sess_name);
} else if (prev_state ==
RDMA_CHANNEL_CONNECTING) {
PRINT_ERROR("%s", "rejected"
" SRP_LOGIN_REQ because another login"
" request is being processed.");
ib_send_cm_rej(ch->cm_id,
IB_CM_REJ_NO_RESOURCES,
NULL, 0, NULL, 0);
scst_unregister_session(ch->scst_sess,
0,
srpt_release_channel);
}
spin_lock_irq(&sdev->spinlock);
}
}
spin_unlock_irq(&sdev->spinlock);
} else
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
if (((u64) (*(u64 *) req->target_port_id) !=
cpu_to_be64(srpt_service_guid)) ||
((u64) (*(u64 *) (req->target_port_id + 8)) !=
cpu_to_be64(srpt_service_guid))) {
rej->reason =
cpu_to_be32(SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL);
ret = -ENOMEM;
PRINT_ERROR("%s", "rejected SRP_LOGIN_REQ because it"
" has an invalid target port identifier.");
goto reject;
}
ch = kzalloc(sizeof *ch, GFP_KERNEL);
if (!ch) {
rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
PRINT_ERROR("%s",
"rejected SRP_LOGIN_REQ because out of memory.");
ret = -ENOMEM;
goto reject;
}
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->losolnt = req->req_flags & SRP_LOSOLNT ? 1 : 0;
ch->crsolnt = req->req_flags & SRP_CRSOLNT ? 1 : 0;
ch->aesolnt = req->req_flags & SRP_AESOLNT ? 1 : 0;
ch->cm_id = cm_id;
atomic_set(&ch->state, RDMA_CHANNEL_CONNECTING);
INIT_LIST_HEAD(&ch->cmd_wait_list);
ret = srpt_alloc_req_ring(ch);
if (ret) {
PRINT_ERROR("%s", "send ring allocation failed");
goto free_ch;
}
ret = srpt_create_ch_ib(ch);
if (ret) {
rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
PRINT_ERROR("%s", "rejected SRP_LOGIN_REQ because creating"
" a new RDMA channel failed.");
goto free_req_ring;
}
ret = srpt_ch_qp_rtr(ch, ch->qp);
if (ret) {
rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
PRINT_ERROR("rejected SRP_LOGIN_REQ because enabling"
" RTR failed (error code = %d)", ret);
goto destroy_ib;
}
if (use_port_guid_in_session_name) {
/*
* If the kernel module parameter use_port_guid_in_session_name
* has been specified, use a combination of the target port
* GUID and the initiator port ID as the session name. This
* was the original behavior of the SRP target implementation
* (i.e. before the SRPT was included in OFED 1.3).
*/
snprintf(ch->sess_name, sizeof(ch->sess_name),
"0x%016llx%016llx",
(unsigned long long)be64_to_cpu(*(u64 *)
&sdev->port[param->port - 1].gid.raw[8]),
(unsigned long long)be64_to_cpu(*(u64 *)
(ch->i_port_id + 8)));
} else {
/*
* Default behavior: use the initator port identifier as the
* session name.
*/
snprintf(ch->sess_name, sizeof(ch->sess_name),
"0x%016llx%016llx",
(unsigned long long)be64_to_cpu(*(u64 *)ch->i_port_id),
(unsigned long long)be64_to_cpu(*(u64 *)
(ch->i_port_id + 8)));
}
TRACE_DBG("registering session %s", ch->sess_name);
BUG_ON(!sdev->scst_tgt);
ch->scst_sess = scst_register_session(sdev->scst_tgt, 0, ch->sess_name,
NULL, NULL);
if (!ch->scst_sess) {
rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
TRACE_DBG("%s", "Failed to create scst sess");
goto destroy_ib;
}
TRACE_DBG("Establish connection sess=%p name=%s cm_id=%p",
ch->scst_sess, ch->sess_name, ch->cm_id);
scst_sess_set_tgt_priv(ch->scst_sess, ch);
/* 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 = req->req_it_iu_len;
rsp->buf_fmt =
cpu_to_be16(SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT);
rsp->req_lim_delta = cpu_to_be32(SRPT_RQ_SIZE);
atomic_set(&ch->req_lim, SRPT_RQ_SIZE);
atomic_set(&ch->last_response_req_lim, SRPT_RQ_SIZE);
atomic_set(&ch->send_cred_req, 0);
ch->cred_req_tag = 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) {
PRINT_ERROR("sending SRP_LOGIN_REQ response failed"
" (error code = %d)", 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:
atomic_set(&ch->state, RDMA_CHANNEL_DISCONNECTING);
scst_unregister_session(ch->scst_sess, 0, NULL);
ch->scst_sess = NULL;
destroy_ib:
ib_destroy_qp(ch->qp);
ib_destroy_cq(ch->cq);
free_req_ring:
srpt_free_req_ring(ch);
free_ch:
kfree(ch);
reject:
rej->opcode = SRP_LOGIN_REJ;
rej->tag = req->tag;
rej->buf_fmt =
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)
{
PRINT_INFO("Received InfiniBand REJ packet for cm_id %p.", cm_id);
srpt_release_channel_by_cmid(cm_id);
}
/**
* Process an IB_CM_RTU_RECEIVED or IB_CM_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);
WARN_ON(!ch);
if (!ch)
goto out;
if (srpt_test_and_set_channel_state(ch, RDMA_CHANNEL_CONNECTING,
RDMA_CHANNEL_LIVE) == RDMA_CHANNEL_CONNECTING) {
struct srpt_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);
}
if (ret && srpt_test_and_set_channel_state(ch,
RDMA_CHANNEL_LIVE,
RDMA_CHANNEL_DISCONNECTING) == RDMA_CHANNEL_LIVE) {
TRACE_DBG("cm_id=%p sess_name=%s state=%d",
cm_id, ch->sess_name,
atomic_read(&ch->state));
ib_send_cm_dreq(ch->cm_id, NULL, 0);
}
}
out:
;
}
static void srpt_cm_timewait_exit(struct ib_cm_id *cm_id)
{
PRINT_INFO("Received InfiniBand TimeWait exit for cm_id %p.", cm_id);
srpt_release_channel_by_cmid(cm_id);
}
static void srpt_cm_rep_error(struct ib_cm_id *cm_id)
{
PRINT_INFO("Received InfiniBand REP error for cm_id %p.", cm_id);
srpt_release_channel_by_cmid(cm_id);
}
static void srpt_cm_dreq_recv(struct ib_cm_id *cm_id)
{
struct srpt_rdma_ch *ch;
ch = srpt_find_channel(cm_id->context, cm_id);
WARN_ON(!ch);
if (!ch)
goto out;
TRACE_DBG("cm_id= %p ch->state= %d", cm_id, atomic_read(&ch->state));
switch (atomic_read(&ch->state)) {
case RDMA_CHANNEL_LIVE:
case RDMA_CHANNEL_CONNECTING:
ib_send_cm_drep(ch->cm_id, NULL, 0);
PRINT_INFO("Received DREQ and sent DREP for session %s.",
ch->sess_name);
break;
case RDMA_CHANNEL_DISCONNECTING:
default:
break;
}
out:
;
}
static void srpt_cm_drep_recv(struct ib_cm_id *cm_id)
{
PRINT_INFO("Received InfiniBand DREP message for cm_id %p.", cm_id);
srpt_release_channel_by_cmid(cm_id);
}
/**
* 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;
default:
PRINT_ERROR("received unrecognized IB CM event %d",
event->event);
break;
}
return ret;
}
static int srpt_map_sg_to_ib_sge(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx,
struct scst_cmd *scmnd)
{
struct scatterlist *scat;
scst_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;
scat = scst_cmd_get_sg(scmnd);
dir = scst_cmd_get_data_direction(scmnd);
WARN_ON(scat == NULL);
count = ib_dma_map_sg(ch->sport->sdev->device, scat,
scst_cmd_get_sg_cnt(scmnd),
scst_to_tgt_dma_dir(dir));
if (unlikely(!count))
return -EBUSY;
if (ioctx->rdma_ius && ioctx->n_rdma_ius)
nrdma = ioctx->n_rdma_ius;
else {
nrdma = count / SRPT_DEF_SG_PER_WQE + ioctx->n_rbuf;
ioctx->rdma_ius = kzalloc(nrdma * sizeof *riu,
scst_cmd_atomic(scmnd)
? GFP_ATOMIC : GFP_KERNEL);
if (!ioctx->rdma_ius) {
WARN_ON(scat == NULL);
ib_dma_unmap_sg(ch->sport->sdev->device,
scat, scst_cmd_get_sg_cnt(scmnd),
scst_to_tgt_dma_dir(dir));
return -ENOMEM;
}
ioctx->n_rdma_ius = nrdma;
}
db = ioctx->rbufs;
tsize = (dir == SCST_DATA_READ) ?
scst_cmd_get_resp_data_len(scmnd) : scst_cmd_get_bufflen(scmnd);
dma_len = sg_dma_len(&scat[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)
dma_len = sg_dma_len(&scat[j]);
}
} 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,
scst_cmd_atomic(scmnd)
? GFP_ATOMIC : 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,
scst_cmd_atomic(scmnd)
? GFP_ATOMIC : GFP_KERNEL);
if (!riu->sge)
goto free_mem;
}
db = ioctx->rbufs;
scat = scst_cmd_get_sg(scmnd);
tsize = (dir == SCST_DATA_READ) ?
scst_cmd_get_resp_data_len(scmnd) : scst_cmd_get_bufflen(scmnd);
riu = ioctx->rdma_ius;
dma_len = sg_dma_len(&scat[0]);
dma_addr = sg_dma_address(&scat[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) {
dma_len = sg_dma_len(&scat[j]);
dma_addr =
sg_dma_address(&scat[j]);
}
}
} 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) {
++riu;
sge = riu->sge;
k = 0;
} else if (rsize > 0)
++sge;
}
}
return 0;
free_mem:
srpt_unmap_sg_to_ib_sge(ch, ioctx);
return -ENOMEM;
}
static void srpt_unmap_sg_to_ib_sge(struct srpt_rdma_ch *ch,
struct srpt_ioctx *ioctx)
{
struct scst_cmd *scmnd;
struct scatterlist *scat;
scst_data_direction dir;
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;
scmnd = ioctx->scmnd;
if (scmnd) {
BUG_ON(ioctx != scst_cmd_get_tgt_priv(scmnd));
scat = scst_cmd_get_sg(scmnd);
if (scat) {
dir = scst_cmd_get_data_direction(scmnd);
ib_dma_unmap_sg(ch->sport->sdev->device,
scat, scst_cmd_get_sg_cnt(scmnd),
scst_to_tgt_dma_dir(dir));
}
}
}
static int srpt_perform_rdmas(struct srpt_rdma_ch *ch, struct srpt_ioctx *ioctx,
scst_data_direction dir)
{
struct ib_send_wr wr;
struct ib_send_wr *bad_wr;
struct rdma_iu *riu;
int i;
int ret;
int srq_wr_avail;
if (dir == SCST_DATA_WRITE) {
ret = -ENOMEM;
srq_wr_avail = atomic_sub_return(ioctx->n_rdma,
&ch->qp_wr_avail);
if (srq_wr_avail < 0) {
atomic_add(ioctx->n_rdma, &ch->qp_wr_avail);
PRINT_INFO("%s[%d]: SRQ full", __func__, __LINE__);
goto out;
}
}
ret = 0;
riu = ioctx->rdma_ius;
memset(&wr, 0, sizeof wr);
for (i = 0; i < ioctx->n_rdma; ++i, ++riu) {
wr.opcode = (dir == SCST_DATA_READ) ?
IB_WR_RDMA_WRITE : IB_WR_RDMA_READ;
wr.next = NULL;
wr.wr_id = ioctx->index;
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 wr */
if (i == (ioctx->n_rdma - 1) && dir == SCST_DATA_WRITE)
wr.send_flags = IB_SEND_SIGNALED;
ret = ib_post_send(ch->qp, &wr, &bad_wr);
if (ret)
goto out;
}
out:
return ret;
}
/*
* Start data transfer between initiator and target. Must not block.
*/
static int srpt_xfer_data(struct srpt_rdma_ch *ch, struct srpt_ioctx *ioctx,
struct scst_cmd *scmnd)
{
int ret;
ret = srpt_map_sg_to_ib_sge(ch, ioctx, scmnd);
if (ret) {
PRINT_ERROR("%s[%d] ret=%d", __func__, __LINE__, ret);
ret = SCST_TGT_RES_QUEUE_FULL;
goto out;
}
ret = srpt_perform_rdmas(ch, ioctx, scst_cmd_get_data_direction(scmnd));
if (ret) {
if (ret == -EAGAIN || ret == -ENOMEM) {
PRINT_INFO("%s[%d] queue full -- ret=%d",
__func__, __LINE__, ret);
ret = SCST_TGT_RES_QUEUE_FULL;
} else {
PRINT_ERROR("%s[%d] fatal error -- ret=%d",
__func__, __LINE__, ret);
ret = SCST_TGT_RES_FATAL_ERROR;
}
goto out_unmap;
}
ret = SCST_TGT_RES_SUCCESS;
out:
return ret;
out_unmap:
srpt_unmap_sg_to_ib_sge(ch, ioctx);
goto out;
}
/*
* Called by the SCST core to inform ib_srpt that data reception from the
* initiator should start (SCST_DATA_WRITE). Must not block.
*/
static int srpt_rdy_to_xfer(struct scst_cmd *scmnd)
{
struct srpt_rdma_ch *ch;
struct srpt_ioctx *ioctx;
enum rdma_ch_state ch_state;
int ret;
ioctx = scst_cmd_get_tgt_priv(scmnd);
BUG_ON(!ioctx);
WARN_ON(srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA)
== SRPT_STATE_ABORTED);
ch = ioctx->ch;
WARN_ON(ch != scst_sess_get_tgt_priv(scst_cmd_get_session(scmnd)));
BUG_ON(!ch);
ch_state = atomic_read(&ch->state);
if (ch_state == RDMA_CHANNEL_DISCONNECTING) {
TRACE_DBG("cmd with tag %lld: channel disconnecting",
scst_cmd_get_tag(scmnd));
ret = SCST_TGT_RES_FATAL_ERROR;
goto out;
} else if (ch_state == RDMA_CHANNEL_CONNECTING) {
ret = SCST_TGT_RES_QUEUE_FULL;
goto out;
}
ret = srpt_xfer_data(ch, ioctx, scmnd);
out:
return ret;
}
/**
* srpt_xmit_response() - SCST callback function that transmits the response
* to a SCSI command.
*
* Must not block.
*/
static int srpt_xmit_response(struct scst_cmd *scmnd)
{
struct srpt_rdma_ch *ch;
struct srpt_ioctx *ioctx;
s32 req_lim_delta;
int ret = SCST_TGT_RES_SUCCESS;
int dir;
int resp_len;
ioctx = scst_cmd_get_tgt_priv(scmnd);
BUG_ON(!ioctx);
ch = scst_sess_get_tgt_priv(scst_cmd_get_session(scmnd));
BUG_ON(!ch);
if (unlikely(scst_cmd_aborted(scmnd))) {
TRACE_DBG("cmd with tag %lld has been aborted",
scst_cmd_get_tag(scmnd));
srpt_abort_scst_cmd(ch->sport->sdev, scmnd);
ret = SCST_TGT_RES_SUCCESS;
goto out;
}
if (srpt_set_cmd_state(ioctx, SRPT_STATE_PROCESSED)
== SRPT_STATE_ABORTED) {
ret = SCST_TGT_RES_SUCCESS;
goto out;
}
dir = scst_cmd_get_data_direction(scmnd);
/* For read commands, transfer the data to the initiator. */
if (dir == SCST_DATA_READ && scst_cmd_get_resp_data_len(scmnd)) {
ret = srpt_xfer_data(ch, ioctx, scmnd);
if (ret != SCST_TGT_RES_SUCCESS) {
PRINT_ERROR("%s: tag= %lld xfer_data failed",
__func__,
(unsigned long long)
scst_cmd_get_tag(scmnd));
goto out;
}
}
scst_check_convert_sense(scmnd);
req_lim_delta = srpt_req_lim_delta(ch) + 1;
resp_len = srpt_build_cmd_rsp(ch, ioctx, req_lim_delta,
scst_cmd_get_tag(scmnd),
scst_cmd_get_status(scmnd),
scst_cmd_get_sense_buffer(scmnd),
scst_cmd_get_sense_buffer_len(scmnd));
if (srpt_post_send(ch, ioctx, resp_len)) {
PRINT_ERROR("%s[%d]: ch->state= %d tag= %lld",
__func__, __LINE__, atomic_read(&ch->state),
(unsigned long long)scst_cmd_get_tag(scmnd));
atomic_sub(req_lim_delta, &ch->last_response_req_lim);
ret = SCST_TGT_RES_FATAL_ERROR;
}
out:
return ret;
}
/**
* srpt_tsk_mgmt_done() - SCST callback function that sends back the response
* for a task management request.
*
* Must not block.
*/
static void srpt_tsk_mgmt_done(struct scst_mgmt_cmd *mcmnd)
{
struct srpt_rdma_ch *ch;
struct srpt_mgmt_ioctx *mgmt_ioctx;
struct srpt_ioctx *ioctx;
s32 req_lim_delta;
int rsp_len;
mgmt_ioctx = scst_mgmt_cmd_get_tgt_priv(mcmnd);
BUG_ON(!mgmt_ioctx);
ch = mgmt_ioctx->ch;
BUG_ON(!ch);
ioctx = mgmt_ioctx->ioctx;
BUG_ON(!ioctx);
TRACE_DBG("%s: tsk_mgmt_done for tag= %lld status=%d",
__func__, (unsigned long long)mgmt_ioctx->tag,
scst_mgmt_cmd_get_status(mcmnd));
if (srpt_set_cmd_state(ioctx, SRPT_STATE_PROCESSED)
== SRPT_STATE_ABORTED)
goto out;
req_lim_delta = srpt_req_lim_delta(ch) + 1;
rsp_len = srpt_build_tskmgmt_rsp(ch, ioctx, req_lim_delta,
(scst_mgmt_cmd_get_status(mcmnd) ==
SCST_MGMT_STATUS_SUCCESS) ?
SRP_TSK_MGMT_SUCCESS :
SRP_TSK_MGMT_FAILED,
mgmt_ioctx->tag);
if (srpt_post_send(ch, ioctx, rsp_len)) {
PRINT_ERROR("%s", "Sending SRP_RSP response failed.");
atomic_sub(req_lim_delta, &ch->last_response_req_lim);
}
scst_mgmt_cmd_set_tgt_priv(mcmnd, NULL);
kfree(mgmt_ioctx);
out:
;
}
/*
* Called by the SCST core to inform ib_srpt that the command 'scmnd' is about
* to be freed. May be called in IRQ context.
*/
static void srpt_on_free_cmd(struct scst_cmd *scmnd)
{
struct srpt_rdma_ch *ch;
struct srpt_ioctx *ioctx;
ioctx = scst_cmd_get_tgt_priv(scmnd);
BUG_ON(!ioctx);
ch = ioctx->ch;
BUG_ON(!ch);
scst_cmd_set_tgt_priv(scmnd, NULL);
srpt_set_cmd_state(ioctx, SRPT_STATE_ABORTED);
ioctx->scmnd = NULL;
ioctx->ch = NULL;
srpt_reset_ioctx(ch, ioctx);
}
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20) && ! defined(BACKPORT_LINUX_WORKQUEUE_TO_2_6_19)
/* A vanilla 2.6.19 or older kernel without backported OFED kernel headers. */
static void srpt_refresh_port_work(void *ctx)
#else
static void srpt_refresh_port_work(struct work_struct *work)
#endif
{
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20) && ! defined(BACKPORT_LINUX_WORKQUEUE_TO_2_6_19)
struct srpt_port *sport = (struct srpt_port *)ctx;
#else
struct srpt_port *sport = container_of(work, struct srpt_port, work);
#endif
srpt_refresh_port(sport);
}
/*
* Called by the SCST core to detect target adapters. Returns the number of
* detected target adapters.
*/
static int srpt_detect(struct scst_tgt_template *tp)
{
int device_count;
TRACE_ENTRY();
device_count = atomic_read(&srpt_device_count);
TRACE_EXIT_RES(device_count);
return device_count;
}
/*
* Callback function called by the SCST core from scst_unregister() to free up
* the resources associated with device scst_tgt.
*/
static int srpt_release(struct scst_tgt *scst_tgt)
{
struct srpt_device *sdev = scst_tgt_get_tgt_priv(scst_tgt);
struct srpt_rdma_ch *ch, *tmp_ch;
TRACE_ENTRY();
BUG_ON(!scst_tgt);
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
WARN_ON(!sdev);
if (!sdev)
return -ENODEV;
#else
if (WARN_ON(!sdev))
return -ENODEV;
#endif
#ifdef CONFIG_SCST_PROC
srpt_unregister_procfs_entry(scst_tgt->tgtt);
#endif /*CONFIG_SCST_PROC*/
spin_lock_irq(&sdev->spinlock);
list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list) {
list_del(&ch->list);
atomic_set(&ch->state, RDMA_CHANNEL_DISCONNECTING);
spin_unlock_irq(&sdev->spinlock);
scst_unregister_session(ch->scst_sess, true,
srpt_release_channel);
spin_lock_irq(&sdev->spinlock);
}
spin_unlock_irq(&sdev->spinlock);
scst_tgt_set_tgt_priv(scst_tgt, NULL);
TRACE_EXIT();
return 0;
}
/*
* Entry point for ib_srpt's kernel thread. This kernel thread is only created
* when the module parameter 'thread' is not zero (the default is zero).
* This thread processes the ioctx list srpt_thread.thread_ioctx_list.
*
* @pre thread != 0
*/
static int srpt_ioctx_thread(void *arg)
{
struct srpt_ioctx *ioctx;
/* Hibernation / freezing of the SRPT kernel thread is not supported. */
current->flags |= PF_NOFREEZE;
spin_lock_irq(&srpt_thread.thread_lock);
while (!kthread_should_stop()) {
wait_queue_t wait;
init_waitqueue_entry(&wait, current);
if (!srpt_test_ioctx_list()) {
add_wait_queue_exclusive(&ioctx_list_waitQ, &wait);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
if (srpt_test_ioctx_list())
break;
spin_unlock_irq(&srpt_thread.thread_lock);
schedule();
spin_lock_irq(&srpt_thread.thread_lock);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&ioctx_list_waitQ, &wait);
}
while (!list_empty(&srpt_thread.thread_ioctx_list)) {
ioctx = list_entry(srpt_thread.thread_ioctx_list.next,
struct srpt_ioctx, comp_list);
list_del(&ioctx->comp_list);
spin_unlock_irq(&srpt_thread.thread_lock);
switch (ioctx->op) {
case IB_WC_SEND:
srpt_handle_send_comp(ioctx->ch, ioctx,
SCST_CONTEXT_DIRECT);
break;
case IB_WC_RDMA_WRITE:
case IB_WC_RDMA_READ:
srpt_handle_rdma_comp(ioctx->ch, ioctx);
break;
case IB_WC_RECV:
srpt_handle_new_iu(ioctx->ch, ioctx);
break;
default:
PRINT_ERROR("received unrecognized WC opcode"
" %d", ioctx->op);
break;
}
#if defined(CONFIG_SCST_DEBUG)
if (thread_processing_delay_in_us
<= MAX_UDELAY_MS * 1000)
udelay(thread_processing_delay_in_us);
#endif
spin_lock_irq(&srpt_thread.thread_lock);
}
}
spin_unlock_irq(&srpt_thread.thread_lock);
return 0;
}
/* SCST target template for the SRP target implementation. */
static struct scst_tgt_template srpt_template = {
.name = DRV_NAME,
.sg_tablesize = SRPT_DEF_SG_TABLESIZE,
.xmit_response_atomic = 1,
.rdy_to_xfer_atomic = 1,
.detect = srpt_detect,
.release = srpt_release,
.xmit_response = srpt_xmit_response,
.rdy_to_xfer = srpt_rdy_to_xfer,
.on_free_cmd = srpt_on_free_cmd,
.task_mgmt_fn_done = srpt_tsk_mgmt_done
};
/*
* The callback function srpt_release_class_dev() is called whenever a
* device is removed from the /sys/class/infiniband_srpt device class.
* Although this function has been left empty, a release function has been
* defined such that upon module removal no complaint is logged about a
* missing release function.
*/
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
static void srpt_release_class_dev(struct class_device *class_dev)
#else
static void srpt_release_class_dev(struct device *dev)
#endif
{
}
#ifdef CONFIG_SCST_PROC
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
static int srpt_trace_level_show(struct seq_file *seq, void *v)
{
return scst_proc_log_entry_read(seq, trace_flag, NULL);
}
static ssize_t srpt_proc_trace_level_write(struct file *file,
const char __user *buf, size_t length, loff_t *off)
{
return scst_proc_log_entry_write(file, buf, length, &trace_flag,
DEFAULT_SRPT_TRACE_FLAGS, NULL);
}
static struct scst_proc_data srpt_log_proc_data = {
SCST_DEF_RW_SEQ_OP(srpt_proc_trace_level_write)
.show = srpt_trace_level_show,
};
#endif
#endif /* CONFIG_SCST_PROC */
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
static ssize_t show_login_info(struct class_device *class_dev, char *buf)
#else
static ssize_t show_login_info(struct device *dev,
struct device_attribute *attr, char *buf)
#endif
{
struct srpt_device *sdev =
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
container_of(class_dev, struct srpt_device, class_dev);
#else
container_of(dev, struct srpt_device, dev);
#endif
struct srpt_port *sport;
int i;
int len = 0;
for (i = 0; i < sdev->device->phys_port_cnt; i++) {
sport = &sdev->port[i];
len += sprintf(buf + len,
"tid_ext=%016llx,ioc_guid=%016llx,pkey=ffff,"
"dgid=%04x%04x%04x%04x%04x%04x%04x%04x,"
"service_id=%016llx\n",
(unsigned long long) srpt_service_guid,
(unsigned long long) srpt_service_guid,
be16_to_cpu(((__be16 *) sport->gid.raw)[0]),
be16_to_cpu(((__be16 *) sport->gid.raw)[1]),
be16_to_cpu(((__be16 *) sport->gid.raw)[2]),
be16_to_cpu(((__be16 *) sport->gid.raw)[3]),
be16_to_cpu(((__be16 *) sport->gid.raw)[4]),
be16_to_cpu(((__be16 *) sport->gid.raw)[5]),
be16_to_cpu(((__be16 *) sport->gid.raw)[6]),
be16_to_cpu(((__be16 *) sport->gid.raw)[7]),
(unsigned long long) srpt_service_guid);
}
return len;
}
static struct class_attribute srpt_class_attrs[] = {
__ATTR_NULL,
};
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
static struct class_device_attribute srpt_dev_attrs[] = {
#else
static struct device_attribute srpt_dev_attrs[] = {
#endif
__ATTR(login_info, S_IRUGO, show_login_info, NULL),
__ATTR_NULL,
};
static struct class srpt_class = {
.name = "infiniband_srpt",
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
.release = srpt_release_class_dev,
#else
.dev_release = srpt_release_class_dev,
#endif
.class_attrs = srpt_class_attrs,
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
.class_dev_attrs = srpt_dev_attrs,
#else
.dev_attrs = srpt_dev_attrs,
#endif
};
/*
* Callback function called by the InfiniBand core when either an InfiniBand
* device has been added or during the ib_register_client() call for each
* registered InfiniBand device.
*/
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;
TRACE_ENTRY();
TRACE_DBG("device = %p, device->dma_ops = %p", device, device->dma_ops);
sdev = kzalloc(sizeof *sdev, GFP_KERNEL);
if (!sdev)
return;
sdev->device = device;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
sdev->class_dev.class = &srpt_class;
sdev->class_dev.dev = device->dma_device;
snprintf(sdev->class_dev.class_id, BUS_ID_SIZE,
"srpt-%s", device->name);
#else
sdev->dev.class = &srpt_class;
sdev->dev.parent = device->dma_device;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 30)
snprintf(sdev->dev.bus_id, BUS_ID_SIZE, "srpt-%s", device->name);
#else
dev_set_name(&sdev->dev, "srpt-%s", device->name);
#endif
#endif
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
if (class_device_register(&sdev->class_dev))
goto free_dev;
#else
if (device_register(&sdev->dev))
goto free_dev;
#endif
if (ib_query_device(device, &sdev->dev_attr))
goto err_dev;
sdev->pd = ib_alloc_pd(device);
if (IS_ERR(sdev->pd))
goto err_dev;
sdev->mr = ib_get_dma_mr(sdev->pd, IB_ACCESS_LOCAL_WRITE);
if (IS_ERR(sdev->mr))
goto err_pd;
srq_attr.event_handler = srpt_srq_event;
srq_attr.srq_context = (void *)sdev;
srq_attr.attr.max_wr = min(SRPT_SRQ_SIZE, sdev->dev_attr.max_srq_wr);
srq_attr.attr.max_sge = 1;
srq_attr.attr.srq_limit = 0;
sdev->srq = ib_create_srq(sdev->pd, &srq_attr);
if (IS_ERR(sdev->srq))
goto err_mr;
TRACE_DBG("%s: create SRQ #wr= %d max_allow=%d dev= %s",
__func__, srq_attr.attr.max_wr,
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 */
TRACE_DBG("Target login info: id_ext=%016llx,"
"ioc_guid=%016llx,pkey=ffff,service_id=%016llx",
(unsigned long long) srpt_service_guid,
(unsigned long long) srpt_service_guid,
(unsigned long long) 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;
if (srpt_alloc_ioctx_ring(sdev, sdev->ioctx_ring,
ARRAY_SIZE(sdev->ioctx_ring), 0))
goto err_event;
INIT_LIST_HEAD(&sdev->rch_list);
spin_lock_init(&sdev->spinlock);
for (i = 0; i < SRPT_SRQ_SIZE; ++i)
srpt_post_recv(sdev, sdev->ioctx_ring[i]);
ib_set_client_data(device, &srpt_client, sdev);
sdev->scst_tgt = scst_register(&srpt_template, NULL);
if (!sdev->scst_tgt) {
PRINT_ERROR("SCST registration failed for %s.",
sdev->device->name);
goto err_ring;
}
scst_tgt_set_tgt_priv(sdev->scst_tgt, sdev);
WARN_ON(sdev->device->phys_port_cnt
> sizeof(sdev->port)/sizeof(sdev->port[0]));
for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
sport = &sdev->port[i - 1];
sport->sdev = sdev;
sport->port = i;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20) && ! defined(BACKPORT_LINUX_WORKQUEUE_TO_2_6_19)
/*
* A vanilla 2.6.19 or older kernel without backported OFED
* kernel headers.
*/
INIT_WORK(&sport->work, srpt_refresh_port_work, sport);
#else
INIT_WORK(&sport->work, srpt_refresh_port_work);
#endif
if (srpt_refresh_port(sport)) {
PRINT_ERROR("MAD registration failed for %s-%d.",
sdev->device->name, i);
goto err_refresh_port;
}
}
atomic_inc(&srpt_device_count);
TRACE_EXIT();
return;
err_refresh_port:
scst_unregister(sdev->scst_tgt);
err_ring:
ib_set_client_data(device, &srpt_client, NULL);
srpt_free_ioctx_ring(sdev, sdev->ioctx_ring,
ARRAY_SIZE(sdev->ioctx_ring));
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);
err_dev:
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
class_device_unregister(&sdev->class_dev);
#else
device_unregister(&sdev->dev);
#endif
free_dev:
kfree(sdev);
TRACE_EXIT();
}
/*
* Callback function called by the InfiniBand core when either an InfiniBand
* device has been removed or during the ib_unregister_client() call for each
* registered InfiniBand device.
*/
static void srpt_remove_one(struct ib_device *device)
{
int i;
struct srpt_device *sdev;
TRACE_ENTRY();
sdev = ib_get_client_data(device, &srpt_client);
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
WARN_ON(!sdev);
if (!sdev)
return;
#else
if (WARN_ON(!sdev))
return;
#endif
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++)
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 22)
cancel_work_sync(&sdev->port[i].work);
#else
/*
* cancel_work_sync() was introduced in kernel 2.6.22. Older
* kernels do not have a facility to cancel scheduled work, so
* wait until the scheduled work finished.
*/
flush_workqueue(&sdev->port[i].work);
#endif
ib_destroy_cm_id(sdev->cm_id);
ib_destroy_srq(sdev->srq);
ib_dereg_mr(sdev->mr);
ib_dealloc_pd(sdev->pd);
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26)
class_device_unregister(&sdev->class_dev);
#else
device_unregister(&sdev->dev);
#endif
/*
* Unregistering an SCST target must happen after destroying sdev->cm_id
* such that no new SRP_LOGIN_REQ information units can arrive while
* destroying the SCST target.
*/
scst_unregister(sdev->scst_tgt);
sdev->scst_tgt = NULL;
srpt_free_ioctx_ring(sdev, sdev->ioctx_ring,
ARRAY_SIZE(sdev->ioctx_ring));
kfree(sdev);
TRACE_EXIT();
}
#ifdef CONFIG_SCST_PROC
/**
* Create procfs entries for srpt. Currently the only procfs entry created
* by this function is the "trace_level" entry.
*/
static int srpt_register_procfs_entry(struct scst_tgt_template *tgt)
{
int res = 0;
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
struct proc_dir_entry *p, *root;
root = scst_proc_get_tgt_root(tgt);
WARN_ON(!root);
if (root) {
/*
* Fill in the scst_proc_data::data pointer, which is used in
* a printk(KERN_INFO ...) statement in
* scst_proc_log_entry_write() in scst_proc.c.
*/
srpt_log_proc_data.data = (char *)tgt->name;
p = scst_create_proc_entry(root, SRPT_PROC_TRACE_LEVEL_NAME,
&srpt_log_proc_data);
if (!p)
res = -ENOMEM;
} else
res = -ENOMEM;
#endif
return res;
}
static void srpt_unregister_procfs_entry(struct scst_tgt_template *tgt)
{
#if defined(CONFIG_SCST_DEBUG) || defined(CONFIG_SCST_TRACING)
struct proc_dir_entry *root;
root = scst_proc_get_tgt_root(tgt);
WARN_ON(!root);
if (root)
remove_proc_entry(SRPT_PROC_TRACE_LEVEL_NAME, root);
#endif
}
#endif /*CONFIG_SCST_PROC*/
/*
* Module initialization.
*
* Note: since ib_register_client() registers callback functions, and since at
* least one of these callback functions (srpt_add_one()) calls SCST functions,
* the SCST target template must be registered before ib_register_client() is
* called.
*/
static int __init srpt_init_module(void)
{
int ret;
ret = -EINVAL;
if (srp_max_message_size < MIN_MAX_MESSAGE_SIZE) {
PRINT_ERROR("invalid value %d for kernel module parameter"
" srp_max_message_size -- must be at least %d.",
srp_max_message_size,
MIN_MAX_MESSAGE_SIZE);
goto out;
}
ret = class_register(&srpt_class);
if (ret) {
PRINT_ERROR("%s", "couldn't register class ib_srpt");
goto out;
}
ret = scst_register_target_template(&srpt_template);
if (ret < 0) {
PRINT_ERROR("%s", "couldn't register with scst");
ret = -ENODEV;
goto out_unregister_class;
}
#ifdef CONFIG_SCST_PROC
ret = srpt_register_procfs_entry(&srpt_template);
if (ret) {
PRINT_ERROR("%s", "couldn't register procfs entry");
goto out_unregister_target;
}
#endif /*CONFIG_SCST_PROC*/
ret = ib_register_client(&srpt_client);
if (ret) {
PRINT_ERROR("%s", "couldn't register IB client");
goto out_unregister_target;
}
if (thread) {
spin_lock_init(&srpt_thread.thread_lock);
INIT_LIST_HEAD(&srpt_thread.thread_ioctx_list);
srpt_thread.thread = kthread_run(srpt_ioctx_thread,
NULL, "srpt_thread");
if (IS_ERR(srpt_thread.thread)) {
srpt_thread.thread = NULL;
thread = 0;
}
}
return 0;
out_unregister_target:
#ifdef CONFIG_SCST_PROC
/*
* Note: the procfs entry is unregistered in srpt_release(), which is
* called by scst_unregister_target_template().
*/
#endif /*CONFIG_SCST_PROC*/
scst_unregister_target_template(&srpt_template);
out_unregister_class:
class_unregister(&srpt_class);
out:
return ret;
}
static void __exit srpt_cleanup_module(void)
{
TRACE_ENTRY();
ib_unregister_client(&srpt_client);
scst_unregister_target_template(&srpt_template);
if (srpt_thread.thread)
kthread_stop(srpt_thread.thread);
class_unregister(&srpt_class);
TRACE_EXIT();
}
module_init(srpt_init_module);
module_exit(srpt_cleanup_module);
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