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gerrit-public.fairphone.software / kernel / msm-4.19 / 2088ca66f5e986c06dc1deb4e2f004218b652300 / . / drivers / infiniband / ulp / srp / ib_srp.c
blob: 890322637e2ee0f512fe248fea80ccf6bb524d3e [file] [log] [blame]
/*
* Copyright (c) 2005 Cisco Systems. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#define pr_fmt(fmt) PFX fmt
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/string.h>
#include <linux/parser.h>
#include <linux/random.h>
#include <linux/jiffies.h>
#include <linux/atomic.h>
#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_tcq.h>
#include <scsi/srp.h>
#include <scsi/scsi_transport_srp.h>
#include "ib_srp.h"
#define DRV_NAME "ib_srp"
#define PFX DRV_NAME ": "
#define DRV_VERSION "1.0"
#define DRV_RELDATE "July 1, 2013"
MODULE_AUTHOR("Roland Dreier");
MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
"v" DRV_VERSION " (" DRV_RELDATE ")");
MODULE_LICENSE("Dual BSD/GPL");
static unsigned int srp_sg_tablesize;
static unsigned int cmd_sg_entries;
static unsigned int indirect_sg_entries;
static bool allow_ext_sg;
static int topspin_workarounds = 1;
module_param(srp_sg_tablesize, uint, 0444);
MODULE_PARM_DESC(srp_sg_tablesize, "Deprecated name for cmd_sg_entries");
module_param(cmd_sg_entries, uint, 0444);
MODULE_PARM_DESC(cmd_sg_entries,
"Default number of gather/scatter entries in the SRP command (default is 12, max 255)");
module_param(indirect_sg_entries, uint, 0444);
MODULE_PARM_DESC(indirect_sg_entries,
"Default max number of gather/scatter entries (default is 12, max is " __stringify(SCSI_MAX_SG_CHAIN_SEGMENTS) ")");
module_param(allow_ext_sg, bool, 0444);
MODULE_PARM_DESC(allow_ext_sg,
"Default behavior when there are more than cmd_sg_entries S/G entries after mapping; fails the request when false (default false)");
module_param(topspin_workarounds, int, 0444);
MODULE_PARM_DESC(topspin_workarounds,
"Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
static struct kernel_param_ops srp_tmo_ops;
static int srp_reconnect_delay = 10;
module_param_cb(reconnect_delay, &srp_tmo_ops, &srp_reconnect_delay,
S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(reconnect_delay, "Time between successive reconnect attempts");
static int srp_fast_io_fail_tmo = 15;
module_param_cb(fast_io_fail_tmo, &srp_tmo_ops, &srp_fast_io_fail_tmo,
S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(fast_io_fail_tmo,
"Number of seconds between the observation of a transport"
" layer error and failing all I/O. \"off\" means that this"
" functionality is disabled.");
static int srp_dev_loss_tmo = 600;
module_param_cb(dev_loss_tmo, &srp_tmo_ops, &srp_dev_loss_tmo,
S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dev_loss_tmo,
"Maximum number of seconds that the SRP transport should"
" insulate transport layer errors. After this time has been"
" exceeded the SCSI host is removed. Should be"
" between 1 and " __stringify(SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
" if fast_io_fail_tmo has not been set. \"off\" means that"
" this functionality is disabled.");
static void srp_add_one(struct ib_device *device);
static void srp_remove_one(struct ib_device *device);
static void srp_recv_completion(struct ib_cq *cq, void *target_ptr);
static void srp_send_completion(struct ib_cq *cq, void *target_ptr);
static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
static struct scsi_transport_template *ib_srp_transport_template;
static struct ib_client srp_client = {
.name = "srp",
.add = srp_add_one,
.remove = srp_remove_one
};
static struct ib_sa_client srp_sa_client;
static int srp_tmo_get(char *buffer, const struct kernel_param *kp)
{
int tmo = *(int *)kp->arg;
if (tmo >= 0)
return sprintf(buffer, "%d", tmo);
else
return sprintf(buffer, "off");
}
static int srp_tmo_set(const char *val, const struct kernel_param *kp)
{
int tmo, res;
if (strncmp(val, "off", 3) != 0) {
res = kstrtoint(val, 0, &tmo);
if (res)
goto out;
} else {
tmo = -1;
}
if (kp->arg == &srp_reconnect_delay)
res = srp_tmo_valid(tmo, srp_fast_io_fail_tmo,
srp_dev_loss_tmo);
else if (kp->arg == &srp_fast_io_fail_tmo)
res = srp_tmo_valid(srp_reconnect_delay, tmo, srp_dev_loss_tmo);
else
res = srp_tmo_valid(srp_reconnect_delay, srp_fast_io_fail_tmo,
tmo);
if (res)
goto out;
*(int *)kp->arg = tmo;
out:
return res;
}
static struct kernel_param_ops srp_tmo_ops = {
.get = srp_tmo_get,
.set = srp_tmo_set,
};
static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
{
return (struct srp_target_port *) host->hostdata;
}
static const char *srp_target_info(struct Scsi_Host *host)
{
return host_to_target(host)->target_name;
}
static int srp_target_is_topspin(struct srp_target_port *target)
{
static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
static const u8 cisco_oui[3] = { 0x00, 0x1b, 0x0d };
return topspin_workarounds &&
(!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
!memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
}
static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
gfp_t gfp_mask,
enum dma_data_direction direction)
{
struct srp_iu *iu;
iu = kmalloc(sizeof *iu, gfp_mask);
if (!iu)
goto out;
iu->buf = kzalloc(size, gfp_mask);
if (!iu->buf)
goto out_free_iu;
iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
direction);
if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
goto out_free_buf;
iu->size = size;
iu->direction = direction;
return iu;
out_free_buf:
kfree(iu->buf);
out_free_iu:
kfree(iu);
out:
return NULL;
}
static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
{
if (!iu)
return;
ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
iu->direction);
kfree(iu->buf);
kfree(iu);
}
static void srp_qp_event(struct ib_event *event, void *context)
{
pr_debug("QP event %d\n", event->event);
}
static int srp_init_qp(struct srp_target_port *target,
struct ib_qp *qp)
{
struct ib_qp_attr *attr;
int ret;
attr = kmalloc(sizeof *attr, GFP_KERNEL);
if (!attr)
return -ENOMEM;
ret = ib_find_pkey(target->srp_host->srp_dev->dev,
target->srp_host->port,
be16_to_cpu(target->path.pkey),
&attr->pkey_index);
if (ret)
goto out;
attr->qp_state = IB_QPS_INIT;
attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
IB_ACCESS_REMOTE_WRITE);
attr->port_num = target->srp_host->port;
ret = ib_modify_qp(qp, attr,
IB_QP_STATE |
IB_QP_PKEY_INDEX |
IB_QP_ACCESS_FLAGS |
IB_QP_PORT);
out:
kfree(attr);
return ret;
}
static int srp_new_cm_id(struct srp_target_port *target)
{
struct ib_cm_id *new_cm_id;
new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
srp_cm_handler, target);
if (IS_ERR(new_cm_id))
return PTR_ERR(new_cm_id);
if (target->cm_id)
ib_destroy_cm_id(target->cm_id);
target->cm_id = new_cm_id;
return 0;
}
static int srp_create_target_ib(struct srp_target_port *target)
{
struct ib_qp_init_attr *init_attr;
struct ib_cq *recv_cq, *send_cq;
struct ib_qp *qp;
int ret;
init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
if (!init_attr)
return -ENOMEM;
recv_cq = ib_create_cq(target->srp_host->srp_dev->dev,
srp_recv_completion, NULL, target,
target->queue_size, target->comp_vector);
if (IS_ERR(recv_cq)) {
ret = PTR_ERR(recv_cq);
goto err;
}
send_cq = ib_create_cq(target->srp_host->srp_dev->dev,
srp_send_completion, NULL, target,
target->queue_size, target->comp_vector);
if (IS_ERR(send_cq)) {
ret = PTR_ERR(send_cq);
goto err_recv_cq;
}
ib_req_notify_cq(recv_cq, IB_CQ_NEXT_COMP);
init_attr->event_handler = srp_qp_event;
init_attr->cap.max_send_wr = target->queue_size;
init_attr->cap.max_recv_wr = target->queue_size;
init_attr->cap.max_recv_sge = 1;
init_attr->cap.max_send_sge = 1;
init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
init_attr->qp_type = IB_QPT_RC;
init_attr->send_cq = send_cq;
init_attr->recv_cq = recv_cq;
qp = ib_create_qp(target->srp_host->srp_dev->pd, init_attr);
if (IS_ERR(qp)) {
ret = PTR_ERR(qp);
goto err_send_cq;
}
ret = srp_init_qp(target, qp);
if (ret)
goto err_qp;
if (target->qp)
ib_destroy_qp(target->qp);
if (target->recv_cq)
ib_destroy_cq(target->recv_cq);
if (target->send_cq)
ib_destroy_cq(target->send_cq);
target->qp = qp;
target->recv_cq = recv_cq;
target->send_cq = send_cq;
kfree(init_attr);
return 0;
err_qp:
ib_destroy_qp(qp);
err_send_cq:
ib_destroy_cq(send_cq);
err_recv_cq:
ib_destroy_cq(recv_cq);
err:
kfree(init_attr);
return ret;
}
/*
* Note: this function may be called without srp_alloc_iu_bufs() having been
* invoked. Hence the target->[rt]x_ring checks.
*/
static void srp_free_target_ib(struct srp_target_port *target)
{
int i;
ib_destroy_qp(target->qp);
ib_destroy_cq(target->send_cq);
ib_destroy_cq(target->recv_cq);
target->qp = NULL;
target->send_cq = target->recv_cq = NULL;
if (target->rx_ring) {
for (i = 0; i < target->queue_size; ++i)
srp_free_iu(target->srp_host, target->rx_ring[i]);
kfree(target->rx_ring);
target->rx_ring = NULL;
}
if (target->tx_ring) {
for (i = 0; i < target->queue_size; ++i)
srp_free_iu(target->srp_host, target->tx_ring[i]);
kfree(target->tx_ring);
target->tx_ring = NULL;
}
}
static void srp_path_rec_completion(int status,
struct ib_sa_path_rec *pathrec,
void *target_ptr)
{
struct srp_target_port *target = target_ptr;
target->status = status;
if (status)
shost_printk(KERN_ERR, target->scsi_host,
PFX "Got failed path rec status %d\n", status);
else
target->path = *pathrec;
complete(&target->done);
}
static int srp_lookup_path(struct srp_target_port *target)
{
target->path.numb_path = 1;
init_completion(&target->done);
target->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
target->srp_host->srp_dev->dev,
target->srp_host->port,
&target->path,
IB_SA_PATH_REC_SERVICE_ID |
IB_SA_PATH_REC_DGID |
IB_SA_PATH_REC_SGID |
IB_SA_PATH_REC_NUMB_PATH |
IB_SA_PATH_REC_PKEY,
SRP_PATH_REC_TIMEOUT_MS,
GFP_KERNEL,
srp_path_rec_completion,
target, &target->path_query);
if (target->path_query_id < 0)
return target->path_query_id;
wait_for_completion(&target->done);
if (target->status < 0)
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Path record query failed\n");
return target->status;
}
static int srp_send_req(struct srp_target_port *target)
{
struct {
struct ib_cm_req_param param;
struct srp_login_req priv;
} *req = NULL;
int status;
req = kzalloc(sizeof *req, GFP_KERNEL);
if (!req)
return -ENOMEM;
req->param.primary_path = &target->path;
req->param.alternate_path = NULL;
req->param.service_id = target->service_id;
req->param.qp_num = target->qp->qp_num;
req->param.qp_type = target->qp->qp_type;
req->param.private_data = &req->priv;
req->param.private_data_len = sizeof req->priv;
req->param.flow_control = 1;
get_random_bytes(&req->param.starting_psn, 4);
req->param.starting_psn &= 0xffffff;
/*
* Pick some arbitrary defaults here; we could make these
* module parameters if anyone cared about setting them.
*/
req->param.responder_resources = 4;
req->param.remote_cm_response_timeout = 20;
req->param.local_cm_response_timeout = 20;
req->param.retry_count = target->tl_retry_count;
req->param.rnr_retry_count = 7;
req->param.max_cm_retries = 15;
req->priv.opcode = SRP_LOGIN_REQ;
req->priv.tag = 0;
req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
req->priv.req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
SRP_BUF_FORMAT_INDIRECT);
/*
* In the published SRP specification (draft rev. 16a), the
* port identifier format is 8 bytes of ID extension followed
* by 8 bytes of GUID. Older drafts put the two halves in the
* opposite order, so that the GUID comes first.
*
* Targets conforming to these obsolete drafts can be
* recognized by the I/O Class they report.
*/
if (target->io_class == SRP_REV10_IB_IO_CLASS) {
memcpy(req->priv.initiator_port_id,
&target->path.sgid.global.interface_id, 8);
memcpy(req->priv.initiator_port_id + 8,
&target->initiator_ext, 8);
memcpy(req->priv.target_port_id, &target->ioc_guid, 8);
memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
} else {
memcpy(req->priv.initiator_port_id,
&target->initiator_ext, 8);
memcpy(req->priv.initiator_port_id + 8,
&target->path.sgid.global.interface_id, 8);
memcpy(req->priv.target_port_id, &target->id_ext, 8);
memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
}
/*
* Topspin/Cisco SRP targets will reject our login unless we
* zero out the first 8 bytes of our initiator port ID and set
* the second 8 bytes to the local node GUID.
*/
if (srp_target_is_topspin(target)) {
shost_printk(KERN_DEBUG, target->scsi_host,
PFX "Topspin/Cisco initiator port ID workaround "
"activated for target GUID %016llx\n",
(unsigned long long) be64_to_cpu(target->ioc_guid));
memset(req->priv.initiator_port_id, 0, 8);
memcpy(req->priv.initiator_port_id + 8,
&target->srp_host->srp_dev->dev->node_guid, 8);
}
status = ib_send_cm_req(target->cm_id, &req->param);
kfree(req);
return status;
}
static bool srp_queue_remove_work(struct srp_target_port *target)
{
bool changed = false;
spin_lock_irq(&target->lock);
if (target->state != SRP_TARGET_REMOVED) {
target->state = SRP_TARGET_REMOVED;
changed = true;
}
spin_unlock_irq(&target->lock);
if (changed)
queue_work(system_long_wq, &target->remove_work);
return changed;
}
static bool srp_change_conn_state(struct srp_target_port *target,
bool connected)
{
bool changed = false;
spin_lock_irq(&target->lock);
if (target->connected != connected) {
target->connected = connected;
changed = true;
}
spin_unlock_irq(&target->lock);
return changed;
}
static void srp_disconnect_target(struct srp_target_port *target)
{
if (srp_change_conn_state(target, false)) {
/* XXX should send SRP_I_LOGOUT request */
if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
shost_printk(KERN_DEBUG, target->scsi_host,
PFX "Sending CM DREQ failed\n");
}
}
}
static void srp_free_req_data(struct srp_target_port *target)
{
struct ib_device *ibdev = target->srp_host->srp_dev->dev;
struct srp_request *req;
int i;
if (!target->req_ring)
return;
for (i = 0; i < target->req_ring_size; ++i) {
req = &target->req_ring[i];
kfree(req->fmr_list);
kfree(req->map_page);
if (req->indirect_dma_addr) {
ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
target->indirect_size,
DMA_TO_DEVICE);
}
kfree(req->indirect_desc);
}
kfree(target->req_ring);
target->req_ring = NULL;
}
static int srp_alloc_req_data(struct srp_target_port *target)
{
struct srp_device *srp_dev = target->srp_host->srp_dev;
struct ib_device *ibdev = srp_dev->dev;
struct srp_request *req;
dma_addr_t dma_addr;
int i, ret = -ENOMEM;
INIT_LIST_HEAD(&target->free_reqs);
target->req_ring = kzalloc(target->req_ring_size *
sizeof(*target->req_ring), GFP_KERNEL);
if (!target->req_ring)
goto out;
for (i = 0; i < target->req_ring_size; ++i) {
req = &target->req_ring[i];
req->fmr_list = kmalloc(target->cmd_sg_cnt * sizeof(void *),
GFP_KERNEL);
req->map_page = kmalloc(SRP_FMR_SIZE * sizeof(void *),
GFP_KERNEL);
req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
if (!req->fmr_list || !req->map_page || !req->indirect_desc)
goto out;
dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
target->indirect_size,
DMA_TO_DEVICE);
if (ib_dma_mapping_error(ibdev, dma_addr))
goto out;
req->indirect_dma_addr = dma_addr;
req->index = i;
list_add_tail(&req->list, &target->free_reqs);
}
ret = 0;
out:
return ret;
}
/**
* srp_del_scsi_host_attr() - Remove attributes defined in the host template.
* @shost: SCSI host whose attributes to remove from sysfs.
*
* Note: Any attributes defined in the host template and that did not exist
* before invocation of this function will be ignored.
*/
static void srp_del_scsi_host_attr(struct Scsi_Host *shost)
{
struct device_attribute **attr;
for (attr = shost->hostt->shost_attrs; attr && *attr; ++attr)
device_remove_file(&shost->shost_dev, *attr);
}
static void srp_remove_target(struct srp_target_port *target)
{
WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
srp_del_scsi_host_attr(target->scsi_host);
srp_rport_get(target->rport);
srp_remove_host(target->scsi_host);
scsi_remove_host(target->scsi_host);
srp_stop_rport_timers(target->rport);
srp_disconnect_target(target);
ib_destroy_cm_id(target->cm_id);
srp_free_target_ib(target);
cancel_work_sync(&target->tl_err_work);
srp_rport_put(target->rport);
srp_free_req_data(target);
spin_lock(&target->srp_host->target_lock);
list_del(&target->list);
spin_unlock(&target->srp_host->target_lock);
scsi_host_put(target->scsi_host);
}
static void srp_remove_work(struct work_struct *work)
{
struct srp_target_port *target =
container_of(work, struct srp_target_port, remove_work);
WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
srp_remove_target(target);
}
static void srp_rport_delete(struct srp_rport *rport)
{
struct srp_target_port *target = rport->lld_data;
srp_queue_remove_work(target);
}
static int srp_connect_target(struct srp_target_port *target)
{
int retries = 3;
int ret;
WARN_ON_ONCE(target->connected);
target->qp_in_error = false;
ret = srp_lookup_path(target);
if (ret)
return ret;
while (1) {
init_completion(&target->done);
ret = srp_send_req(target);
if (ret)
return ret;
wait_for_completion(&target->done);
/*
* The CM event handling code will set status to
* SRP_PORT_REDIRECT if we get a port redirect REJ
* back, or SRP_DLID_REDIRECT if we get a lid/qp
* redirect REJ back.
*/
switch (target->status) {
case 0:
srp_change_conn_state(target, true);
return 0;
case SRP_PORT_REDIRECT:
ret = srp_lookup_path(target);
if (ret)
return ret;
break;
case SRP_DLID_REDIRECT:
break;
case SRP_STALE_CONN:
/* Our current CM id was stale, and is now in timewait.
* Try to reconnect with a new one.
*/
if (!retries-- || srp_new_cm_id(target)) {
shost_printk(KERN_ERR, target->scsi_host, PFX
"giving up on stale connection\n");
target->status = -ECONNRESET;
return target->status;
}
shost_printk(KERN_ERR, target->scsi_host, PFX
"retrying stale connection\n");
break;
default:
return target->status;
}
}
}
static void srp_unmap_data(struct scsi_cmnd *scmnd,
struct srp_target_port *target,
struct srp_request *req)
{
struct ib_device *ibdev = target->srp_host->srp_dev->dev;
struct ib_pool_fmr **pfmr;
if (!scsi_sglist(scmnd) ||
(scmnd->sc_data_direction != DMA_TO_DEVICE &&
scmnd->sc_data_direction != DMA_FROM_DEVICE))
return;
pfmr = req->fmr_list;
while (req->nfmr--)
ib_fmr_pool_unmap(*pfmr++);
ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
scmnd->sc_data_direction);
}
/**
* srp_claim_req - Take ownership of the scmnd associated with a request.
* @target: SRP target port.
* @req: SRP request.
* @scmnd: If NULL, take ownership of @req->scmnd. If not NULL, only take
* ownership of @req->scmnd if it equals @scmnd.
*
* Return value:
* Either NULL or a pointer to the SCSI command the caller became owner of.
*/
static struct scsi_cmnd *srp_claim_req(struct srp_target_port *target,
struct srp_request *req,
struct scsi_cmnd *scmnd)
{
unsigned long flags;
spin_lock_irqsave(&target->lock, flags);
if (!scmnd) {
scmnd = req->scmnd;
req->scmnd = NULL;
} else if (req->scmnd == scmnd) {
req->scmnd = NULL;
} else {
scmnd = NULL;
}
spin_unlock_irqrestore(&target->lock, flags);
return scmnd;
}
/**
* srp_free_req() - Unmap data and add request to the free request list.
*/
static void srp_free_req(struct srp_target_port *target,
struct srp_request *req, struct scsi_cmnd *scmnd,
s32 req_lim_delta)
{
unsigned long flags;
srp_unmap_data(scmnd, target, req);
spin_lock_irqsave(&target->lock, flags);
target->req_lim += req_lim_delta;
list_add_tail(&req->list, &target->free_reqs);
spin_unlock_irqrestore(&target->lock, flags);
}
static void srp_finish_req(struct srp_target_port *target,
struct srp_request *req, int result)
{
struct scsi_cmnd *scmnd = srp_claim_req(target, req, NULL);
if (scmnd) {
srp_free_req(target, req, scmnd, 0);
scmnd->result = result;
scmnd->scsi_done(scmnd);
}
}
static void srp_terminate_io(struct srp_rport *rport)
{
struct srp_target_port *target = rport->lld_data;
int i;
for (i = 0; i < target->req_ring_size; ++i) {
struct srp_request *req = &target->req_ring[i];
srp_finish_req(target, req, DID_TRANSPORT_FAILFAST << 16);
}
}
/*
* It is up to the caller to ensure that srp_rport_reconnect() calls are
* serialized and that no concurrent srp_queuecommand(), srp_abort(),
* srp_reset_device() or srp_reset_host() calls will occur while this function
* is in progress. One way to realize that is not to call this function
* directly but to call srp_reconnect_rport() instead since that last function
* serializes calls of this function via rport->mutex and also blocks
* srp_queuecommand() calls before invoking this function.
*/
static int srp_rport_reconnect(struct srp_rport *rport)
{
struct srp_target_port *target = rport->lld_data;
int i, ret;
srp_disconnect_target(target);
/*
* Now get a new local CM ID so that we avoid confusing the target in
* case things are really fouled up. Doing so also ensures that all CM
* callbacks will have finished before a new QP is allocated.
*/
ret = srp_new_cm_id(target);
/*
* Whether or not creating a new CM ID succeeded, create a new
* QP. This guarantees that all completion callback function
* invocations have finished before request resetting starts.
*/
if (ret == 0)
ret = srp_create_target_ib(target);
else
srp_create_target_ib(target);
for (i = 0; i < target->req_ring_size; ++i) {
struct srp_request *req = &target->req_ring[i];
srp_finish_req(target, req, DID_RESET << 16);
}
INIT_LIST_HEAD(&target->free_tx);
for (i = 0; i < target->queue_size; ++i)
list_add(&target->tx_ring[i]->list, &target->free_tx);
if (ret == 0)
ret = srp_connect_target(target);
if (ret == 0)
shost_printk(KERN_INFO, target->scsi_host,
PFX "reconnect succeeded\n");
return ret;
}
static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
unsigned int dma_len, u32 rkey)
{
struct srp_direct_buf *desc = state->desc;
desc->va = cpu_to_be64(dma_addr);
desc->key = cpu_to_be32(rkey);
desc->len = cpu_to_be32(dma_len);
state->total_len += dma_len;
state->desc++;
state->ndesc++;
}
static int srp_map_finish_fmr(struct srp_map_state *state,
struct srp_target_port *target)
{
struct srp_device *dev = target->srp_host->srp_dev;
struct ib_pool_fmr *fmr;
u64 io_addr = 0;
if (!state->npages)
return 0;
if (state->npages == 1) {
srp_map_desc(state, state->base_dma_addr, state->fmr_len,
target->rkey);
state->npages = state->fmr_len = 0;
return 0;
}
fmr = ib_fmr_pool_map_phys(dev->fmr_pool, state->pages,
state->npages, io_addr);
if (IS_ERR(fmr))
return PTR_ERR(fmr);
*state->next_fmr++ = fmr;
state->nfmr++;
srp_map_desc(state, 0, state->fmr_len, fmr->fmr->rkey);
state->npages = state->fmr_len = 0;
return 0;
}
static void srp_map_update_start(struct srp_map_state *state,
struct scatterlist *sg, int sg_index,
dma_addr_t dma_addr)
{
state->unmapped_sg = sg;
state->unmapped_index = sg_index;
state->unmapped_addr = dma_addr;
}
static int srp_map_sg_entry(struct srp_map_state *state,
struct srp_target_port *target,
struct scatterlist *sg, int sg_index,
int use_fmr)
{
struct srp_device *dev = target->srp_host->srp_dev;
struct ib_device *ibdev = dev->dev;
dma_addr_t dma_addr = ib_sg_dma_address(ibdev, sg);
unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
unsigned int len;
int ret;
if (!dma_len)
return 0;
if (use_fmr == SRP_MAP_NO_FMR) {
/* Once we're in direct map mode for a request, we don't
* go back to FMR mode, so no need to update anything
* other than the descriptor.
*/
srp_map_desc(state, dma_addr, dma_len, target->rkey);
return 0;
}
/* If we start at an offset into the FMR page, don't merge into
* the current FMR. Finish it out, and use the kernel's MR for this
* sg entry. This is to avoid potential bugs on some SRP targets
* that were never quite defined, but went away when the initiator
* avoided using FMR on such page fragments.
*/
if (dma_addr & ~dev->fmr_page_mask || dma_len > dev->fmr_max_size) {
ret = srp_map_finish_fmr(state, target);
if (ret)
return ret;
srp_map_desc(state, dma_addr, dma_len, target->rkey);
srp_map_update_start(state, NULL, 0, 0);
return 0;
}
/* If this is the first sg to go into the FMR, save our position.
* We need to know the first unmapped entry, its index, and the
* first unmapped address within that entry to be able to restart
* mapping after an error.
*/
if (!state->unmapped_sg)
srp_map_update_start(state, sg, sg_index, dma_addr);
while (dma_len) {
if (state->npages == SRP_FMR_SIZE) {
ret = srp_map_finish_fmr(state, target);
if (ret)
return ret;
srp_map_update_start(state, sg, sg_index, dma_addr);
}
len = min_t(unsigned int, dma_len, dev->fmr_page_size);
if (!state->npages)
state->base_dma_addr = dma_addr;
state->pages[state->npages++] = dma_addr;
state->fmr_len += len;
dma_addr += len;
dma_len -= len;
}
/* If the last entry of the FMR wasn't a full page, then we need to
* close it out and start a new one -- we can only merge at page
* boundries.
*/
ret = 0;
if (len != dev->fmr_page_size) {
ret = srp_map_finish_fmr(state, target);
if (!ret)
srp_map_update_start(state, NULL, 0, 0);
}
return ret;
}
static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
struct srp_request *req)
{
struct scatterlist *scat, *sg;
struct srp_cmd *cmd = req->cmd->buf;
int i, len, nents, count, use_fmr;
struct srp_device *dev;
struct ib_device *ibdev;
struct srp_map_state state;
struct srp_indirect_buf *indirect_hdr;
u32 table_len;
u8 fmt;
if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
return sizeof (struct srp_cmd);
if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
scmnd->sc_data_direction != DMA_TO_DEVICE) {
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Unhandled data direction %d\n",
scmnd->sc_data_direction);
return -EINVAL;
}
nents = scsi_sg_count(scmnd);
scat = scsi_sglist(scmnd);
dev = target->srp_host->srp_dev;
ibdev = dev->dev;
count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
if (unlikely(count == 0))
return -EIO;
fmt = SRP_DATA_DESC_DIRECT;
len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
if (count == 1) {
/*
* The midlayer only generated a single gather/scatter
* entry, or DMA mapping coalesced everything to a
* single entry. So a direct descriptor along with
* the DMA MR suffices.
*/
struct srp_direct_buf *buf = (void *) cmd->add_data;
buf->va = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
buf->key = cpu_to_be32(target->rkey);
buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
req->nfmr = 0;
goto map_complete;
}
/* We have more than one scatter/gather entry, so build our indirect
* descriptor table, trying to merge as many entries with FMR as we
* can.
*/
indirect_hdr = (void *) cmd->add_data;
ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
target->indirect_size, DMA_TO_DEVICE);
memset(&state, 0, sizeof(state));
state.desc = req->indirect_desc;
state.pages = req->map_page;
state.next_fmr = req->fmr_list;
use_fmr = dev->fmr_pool ? SRP_MAP_ALLOW_FMR : SRP_MAP_NO_FMR;
for_each_sg(scat, sg, count, i) {
if (srp_map_sg_entry(&state, target, sg, i, use_fmr)) {
/* FMR mapping failed, so backtrack to the first
* unmapped entry and continue on without using FMR.
*/
dma_addr_t dma_addr;
unsigned int dma_len;
backtrack:
sg = state.unmapped_sg;
i = state.unmapped_index;
dma_addr = ib_sg_dma_address(ibdev, sg);
dma_len = ib_sg_dma_len(ibdev, sg);
dma_len -= (state.unmapped_addr - dma_addr);
dma_addr = state.unmapped_addr;
use_fmr = SRP_MAP_NO_FMR;
srp_map_desc(&state, dma_addr, dma_len, target->rkey);
}
}
if (use_fmr == SRP_MAP_ALLOW_FMR && srp_map_finish_fmr(&state, target))
goto backtrack;
/* We've mapped the request, now pull as much of the indirect
* descriptor table as we can into the command buffer. If this
* target is not using an external indirect table, we are
* guaranteed to fit into the command, as the SCSI layer won't
* give us more S/G entries than we allow.
*/
req->nfmr = state.nfmr;
if (state.ndesc == 1) {
/* FMR mapping was able to collapse this to one entry,
* so use a direct descriptor.
*/
struct srp_direct_buf *buf = (void *) cmd->add_data;
*buf = req->indirect_desc[0];
goto map_complete;
}
if (unlikely(target->cmd_sg_cnt < state.ndesc &&
!target->allow_ext_sg)) {
shost_printk(KERN_ERR, target->scsi_host,
"Could not fit S/G list into SRP_CMD\n");
return -EIO;
}
count = min(state.ndesc, target->cmd_sg_cnt);
table_len = state.ndesc * sizeof (struct srp_direct_buf);
fmt = SRP_DATA_DESC_INDIRECT;
len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
len += count * sizeof (struct srp_direct_buf);
memcpy(indirect_hdr->desc_list, req->indirect_desc,
count * sizeof (struct srp_direct_buf));
indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
indirect_hdr->table_desc.key = cpu_to_be32(target->rkey);
indirect_hdr->table_desc.len = cpu_to_be32(table_len);
indirect_hdr->len = cpu_to_be32(state.total_len);
if (scmnd->sc_data_direction == DMA_TO_DEVICE)
cmd->data_out_desc_cnt = count;
else
cmd->data_in_desc_cnt = count;
ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
DMA_TO_DEVICE);
map_complete:
if (scmnd->sc_data_direction == DMA_TO_DEVICE)
cmd->buf_fmt = fmt << 4;
else
cmd->buf_fmt = fmt;
return len;
}
/*
* Return an IU and possible credit to the free pool
*/
static void srp_put_tx_iu(struct srp_target_port *target, struct srp_iu *iu,
enum srp_iu_type iu_type)
{
unsigned long flags;
spin_lock_irqsave(&target->lock, flags);
list_add(&iu->list, &target->free_tx);
if (iu_type != SRP_IU_RSP)
++target->req_lim;
spin_unlock_irqrestore(&target->lock, flags);
}
/*
* Must be called with target->lock held to protect req_lim and free_tx.
* If IU is not sent, it must be returned using srp_put_tx_iu().
*
* Note:
* An upper limit for the number of allocated information units for each
* request type is:
* - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
* more than Scsi_Host.can_queue requests.
* - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
* - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
* one unanswered SRP request to an initiator.
*/
static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
enum srp_iu_type iu_type)
{
s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
struct srp_iu *iu;
srp_send_completion(target->send_cq, target);
if (list_empty(&target->free_tx))
return NULL;
/* Initiator responses to target requests do not consume credits */
if (iu_type != SRP_IU_RSP) {
if (target->req_lim <= rsv) {
++target->zero_req_lim;
return NULL;
}
--target->req_lim;
}
iu = list_first_entry(&target->free_tx, struct srp_iu, list);
list_del(&iu->list);
return iu;
}
static int srp_post_send(struct srp_target_port *target,
struct srp_iu *iu, int len)
{
struct ib_sge list;
struct ib_send_wr wr, *bad_wr;
list.addr = iu->dma;
list.length = len;
list.lkey = target->lkey;
wr.next = NULL;
wr.wr_id = (uintptr_t) iu;
wr.sg_list = &list;
wr.num_sge = 1;
wr.opcode = IB_WR_SEND;
wr.send_flags = IB_SEND_SIGNALED;
return ib_post_send(target->qp, &wr, &bad_wr);
}
static int srp_post_recv(struct srp_target_port *target, struct srp_iu *iu)
{
struct ib_recv_wr wr, *bad_wr;
struct ib_sge list;
list.addr = iu->dma;
list.length = iu->size;
list.lkey = target->lkey;
wr.next = NULL;
wr.wr_id = (uintptr_t) iu;
wr.sg_list = &list;
wr.num_sge = 1;
return ib_post_recv(target->qp, &wr, &bad_wr);
}
static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
{
struct srp_request *req;
struct scsi_cmnd *scmnd;
unsigned long flags;
if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
spin_lock_irqsave(&target->lock, flags);
target->req_lim += be32_to_cpu(rsp->req_lim_delta);
spin_unlock_irqrestore(&target->lock, flags);
target->tsk_mgmt_status = -1;
if (be32_to_cpu(rsp->resp_data_len) >= 4)
target->tsk_mgmt_status = rsp->data[3];
complete(&target->tsk_mgmt_done);
} else {
req = &target->req_ring[rsp->tag];
scmnd = srp_claim_req(target, req, NULL);
if (!scmnd) {
shost_printk(KERN_ERR, target->scsi_host,
"Null scmnd for RSP w/tag %016llx\n",
(unsigned long long) rsp->tag);
spin_lock_irqsave(&target->lock, flags);
target->req_lim += be32_to_cpu(rsp->req_lim_delta);
spin_unlock_irqrestore(&target->lock, flags);
return;
}
scmnd->result = rsp->status;
if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
memcpy(scmnd->sense_buffer, rsp->data +
be32_to_cpu(rsp->resp_data_len),
min_t(int, be32_to_cpu(rsp->sense_data_len),
SCSI_SENSE_BUFFERSIZE));
}
if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
srp_free_req(target, req, scmnd,
be32_to_cpu(rsp->req_lim_delta));
scmnd->host_scribble = NULL;
scmnd->scsi_done(scmnd);
}
}
static int srp_response_common(struct srp_target_port *target, s32 req_delta,
void *rsp, int len)
{
struct ib_device *dev = target->srp_host->srp_dev->dev;
unsigned long flags;
struct srp_iu *iu;
int err;
spin_lock_irqsave(&target->lock, flags);
target->req_lim += req_delta;
iu = __srp_get_tx_iu(target, SRP_IU_RSP);
spin_unlock_irqrestore(&target->lock, flags);
if (!iu) {
shost_printk(KERN_ERR, target->scsi_host, PFX
"no IU available to send response\n");
return 1;
}
ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
memcpy(iu->buf, rsp, len);
ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);
err = srp_post_send(target, iu, len);
if (err) {
shost_printk(KERN_ERR, target->scsi_host, PFX
"unable to post response: %d\n", err);
srp_put_tx_iu(target, iu, SRP_IU_RSP);
}
return err;
}
static void srp_process_cred_req(struct srp_target_port *target,
struct srp_cred_req *req)
{
struct srp_cred_rsp rsp = {
.opcode = SRP_CRED_RSP,
.tag = req->tag,
};
s32 delta = be32_to_cpu(req->req_lim_delta);
if (srp_response_common(target, delta, &rsp, sizeof rsp))
shost_printk(KERN_ERR, target->scsi_host, PFX
"problems processing SRP_CRED_REQ\n");
}
static void srp_process_aer_req(struct srp_target_port *target,
struct srp_aer_req *req)
{
struct srp_aer_rsp rsp = {
.opcode = SRP_AER_RSP,
.tag = req->tag,
};
s32 delta = be32_to_cpu(req->req_lim_delta);
shost_printk(KERN_ERR, target->scsi_host, PFX
"ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));
if (srp_response_common(target, delta, &rsp, sizeof rsp))
shost_printk(KERN_ERR, target->scsi_host, PFX
"problems processing SRP_AER_REQ\n");
}
static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
{
struct ib_device *dev = target->srp_host->srp_dev->dev;
struct srp_iu *iu = (struct srp_iu *) (uintptr_t) wc->wr_id;
int res;
u8 opcode;
ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
DMA_FROM_DEVICE);
opcode = *(u8 *) iu->buf;
if (0) {
shost_printk(KERN_ERR, target->scsi_host,
PFX "recv completion, opcode 0x%02x\n", opcode);
print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
iu->buf, wc->byte_len, true);
}
switch (opcode) {
case SRP_RSP:
srp_process_rsp(target, iu->buf);
break;
case SRP_CRED_REQ:
srp_process_cred_req(target, iu->buf);
break;
case SRP_AER_REQ:
srp_process_aer_req(target, iu->buf);
break;
case SRP_T_LOGOUT:
/* XXX Handle target logout */
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Got target logout request\n");
break;
default:
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Unhandled SRP opcode 0x%02x\n", opcode);
break;
}
ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
DMA_FROM_DEVICE);
res = srp_post_recv(target, iu);
if (res != 0)
shost_printk(KERN_ERR, target->scsi_host,
PFX "Recv failed with error code %d\n", res);
}
/**
* srp_tl_err_work() - handle a transport layer error
*
* Note: This function may get invoked before the rport has been created,
* hence the target->rport test.
*/
static void srp_tl_err_work(struct work_struct *work)
{
struct srp_target_port *target;
target = container_of(work, struct srp_target_port, tl_err_work);
if (target->rport)
srp_start_tl_fail_timers(target->rport);
}
static void srp_handle_qp_err(enum ib_wc_status wc_status, bool send_err,
struct srp_target_port *target)
{
if (target->connected && !target->qp_in_error) {
shost_printk(KERN_ERR, target->scsi_host,
PFX "failed %s status %d\n",
send_err ? "send" : "receive",
wc_status);
queue_work(system_long_wq, &target->tl_err_work);
}
target->qp_in_error = true;
}
static void srp_recv_completion(struct ib_cq *cq, void *target_ptr)
{
struct srp_target_port *target = target_ptr;
struct ib_wc wc;
ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
while (ib_poll_cq(cq, 1, &wc) > 0) {
if (likely(wc.status == IB_WC_SUCCESS)) {
srp_handle_recv(target, &wc);
} else {
srp_handle_qp_err(wc.status, false, target);
}
}
}
static void srp_send_completion(struct ib_cq *cq, void *target_ptr)
{
struct srp_target_port *target = target_ptr;
struct ib_wc wc;
struct srp_iu *iu;
while (ib_poll_cq(cq, 1, &wc) > 0) {
if (likely(wc.status == IB_WC_SUCCESS)) {
iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
list_add(&iu->list, &target->free_tx);
} else {
srp_handle_qp_err(wc.status, true, target);
}
}
}
static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
{
struct srp_target_port *target = host_to_target(shost);
struct srp_rport *rport = target->rport;
struct srp_request *req;
struct srp_iu *iu;
struct srp_cmd *cmd;
struct ib_device *dev;
unsigned long flags;
int len, result;
const bool in_scsi_eh = !in_interrupt() && current == shost->ehandler;
/*
* The SCSI EH thread is the only context from which srp_queuecommand()
* can get invoked for blocked devices (SDEV_BLOCK /
* SDEV_CREATED_BLOCK). Avoid racing with srp_reconnect_rport() by
* locking the rport mutex if invoked from inside the SCSI EH.
*/
if (in_scsi_eh)
mutex_lock(&rport->mutex);
result = srp_chkready(target->rport);
if (unlikely(result)) {
scmnd->result = result;
scmnd->scsi_done(scmnd);
goto unlock_rport;
}
spin_lock_irqsave(&target->lock, flags);
iu = __srp_get_tx_iu(target, SRP_IU_CMD);
if (!iu)
goto err_unlock;
req = list_first_entry(&target->free_reqs, struct srp_request, list);
list_del(&req->list);
spin_unlock_irqrestore(&target->lock, flags);
dev = target->srp_host->srp_dev->dev;
ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
DMA_TO_DEVICE);
scmnd->result = 0;
scmnd->host_scribble = (void *) req;
cmd = iu->buf;
memset(cmd, 0, sizeof *cmd);
cmd->opcode = SRP_CMD;
cmd->lun = cpu_to_be64((u64) scmnd->device->lun << 48);
cmd->tag = req->index;
memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
req->scmnd = scmnd;
req->cmd = iu;
len = srp_map_data(scmnd, target, req);
if (len < 0) {
shost_printk(KERN_ERR, target->scsi_host,
PFX "Failed to map data\n");
goto err_iu;
}
ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
DMA_TO_DEVICE);
if (srp_post_send(target, iu, len)) {
shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
goto err_unmap;
}
unlock_rport:
if (in_scsi_eh)
mutex_unlock(&rport->mutex);
return 0;
err_unmap:
srp_unmap_data(scmnd, target, req);
err_iu:
srp_put_tx_iu(target, iu, SRP_IU_CMD);
spin_lock_irqsave(&target->lock, flags);
list_add(&req->list, &target->free_reqs);
err_unlock:
spin_unlock_irqrestore(&target->lock, flags);
if (in_scsi_eh)
mutex_unlock(&rport->mutex);
return SCSI_MLQUEUE_HOST_BUSY;
}
/*
* Note: the resources allocated in this function are freed in
* srp_free_target_ib().
*/
static int srp_alloc_iu_bufs(struct srp_target_port *target)
{
int i;
target->rx_ring = kzalloc(target->queue_size * sizeof(*target->rx_ring),
GFP_KERNEL);
if (!target->rx_ring)
goto err_no_ring;
target->tx_ring = kzalloc(target->queue_size * sizeof(*target->tx_ring),
GFP_KERNEL);
if (!target->tx_ring)
goto err_no_ring;
for (i = 0; i < target->queue_size; ++i) {
target->rx_ring[i] = srp_alloc_iu(target->srp_host,
target->max_ti_iu_len,
GFP_KERNEL, DMA_FROM_DEVICE);
if (!target->rx_ring[i])
goto err;
}
for (i = 0; i < target->queue_size; ++i) {
target->tx_ring[i] = srp_alloc_iu(target->srp_host,
target->max_iu_len,
GFP_KERNEL, DMA_TO_DEVICE);
if (!target->tx_ring[i])
goto err;
list_add(&target->tx_ring[i]->list, &target->free_tx);
}
return 0;
err:
for (i = 0; i < target->queue_size; ++i) {
srp_free_iu(target->srp_host, target->rx_ring[i]);
srp_free_iu(target->srp_host, target->tx_ring[i]);
}
err_no_ring:
kfree(target->tx_ring);
target->tx_ring = NULL;
kfree(target->rx_ring);
target->rx_ring = NULL;
return -ENOMEM;
}
static uint32_t srp_compute_rq_tmo(struct ib_qp_attr *qp_attr, int attr_mask)
{
uint64_t T_tr_ns, max_compl_time_ms;
uint32_t rq_tmo_jiffies;
/*
* According to section 11.2.4.2 in the IBTA spec (Modify Queue Pair,
* table 91), both the QP timeout and the retry count have to be set
* for RC QP's during the RTR to RTS transition.
*/
WARN_ON_ONCE((attr_mask & (IB_QP_TIMEOUT | IB_QP_RETRY_CNT)) !=
(IB_QP_TIMEOUT | IB_QP_RETRY_CNT));
/*
* Set target->rq_tmo_jiffies to one second more than the largest time
* it can take before an error completion is generated. See also
* C9-140..142 in the IBTA spec for more information about how to
* convert the QP Local ACK Timeout value to nanoseconds.
*/
T_tr_ns = 4096 * (1ULL << qp_attr->timeout);
max_compl_time_ms = qp_attr->retry_cnt * 4 * T_tr_ns;
do_div(max_compl_time_ms, NSEC_PER_MSEC);
rq_tmo_jiffies = msecs_to_jiffies(max_compl_time_ms + 1000);
return rq_tmo_jiffies;
}
static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
struct srp_login_rsp *lrsp,
struct srp_target_port *target)
{
struct ib_qp_attr *qp_attr = NULL;
int attr_mask = 0;
int ret;
int i;
if (lrsp->opcode == SRP_LOGIN_RSP) {
target->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
target->req_lim = be32_to_cpu(lrsp->req_lim_delta);
/*
* Reserve credits for task management so we don't
* bounce requests back to the SCSI mid-layer.
*/
target->scsi_host->can_queue
= min(target->req_lim - SRP_TSK_MGMT_SQ_SIZE,
target->scsi_host->can_queue);
target->scsi_host->cmd_per_lun
= min_t(int, target->scsi_host->can_queue,
target->scsi_host->cmd_per_lun);
} else {
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
ret = -ECONNRESET;
goto error;
}
if (!target->rx_ring) {
ret = srp_alloc_iu_bufs(target);
if (ret)
goto error;
}
ret = -ENOMEM;
qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
if (!qp_attr)
goto error;
qp_attr->qp_state = IB_QPS_RTR;
ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
if (ret)
goto error_free;
ret = ib_modify_qp(target->qp, qp_attr, attr_mask);
if (ret)
goto error_free;
for (i = 0; i < target->queue_size; i++) {
struct srp_iu *iu = target->rx_ring[i];
ret = srp_post_recv(target, iu);
if (ret)
goto error_free;
}
qp_attr->qp_state = IB_QPS_RTS;
ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
if (ret)
goto error_free;
target->rq_tmo_jiffies = srp_compute_rq_tmo(qp_attr, attr_mask);
ret = ib_modify_qp(target->qp, qp_attr, attr_mask);
if (ret)
goto error_free;
ret = ib_send_cm_rtu(cm_id, NULL, 0);
error_free:
kfree(qp_attr);
error:
target->status = ret;
}
static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
struct ib_cm_event *event,
struct srp_target_port *target)
{
struct Scsi_Host *shost = target->scsi_host;
struct ib_class_port_info *cpi;
int opcode;
switch (event->param.rej_rcvd.reason) {
case IB_CM_REJ_PORT_CM_REDIRECT:
cpi = event->param.rej_rcvd.ari;
target->path.dlid = cpi->redirect_lid;
target->path.pkey = cpi->redirect_pkey;
cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
target->status = target->path.dlid ?
SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
break;
case IB_CM_REJ_PORT_REDIRECT:
if (srp_target_is_topspin(target)) {
/*
* Topspin/Cisco SRP gateways incorrectly send
* reject reason code 25 when they mean 24
* (port redirect).
*/
memcpy(target->path.dgid.raw,
event->param.rej_rcvd.ari, 16);
shost_printk(KERN_DEBUG, shost,
PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
(unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
(unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
target->status = SRP_PORT_REDIRECT;
} else {
shost_printk(KERN_WARNING, shost,
" REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
target->status = -ECONNRESET;
}
break;
case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
shost_printk(KERN_WARNING, shost,
" REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
target->status = -ECONNRESET;
break;
case IB_CM_REJ_CONSUMER_DEFINED:
opcode = *(u8 *) event->private_data;
if (opcode == SRP_LOGIN_REJ) {
struct srp_login_rej *rej = event->private_data;
u32 reason = be32_to_cpu(rej->reason);
if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
shost_printk(KERN_WARNING, shost,
PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
else
shost_printk(KERN_WARNING, shost,
PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
} else
shost_printk(KERN_WARNING, shost,
" REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
" opcode 0x%02x\n", opcode);
target->status = -ECONNRESET;
break;
case IB_CM_REJ_STALE_CONN:
shost_printk(KERN_WARNING, shost, " REJ reason: stale connection\n");
target->status = SRP_STALE_CONN;
break;
default:
shost_printk(KERN_WARNING, shost, " REJ reason 0x%x\n",
event->param.rej_rcvd.reason);
target->status = -ECONNRESET;
}
}
static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
{
struct srp_target_port *target = cm_id->context;
int comp = 0;
switch (event->event) {
case IB_CM_REQ_ERROR:
shost_printk(KERN_DEBUG, target->scsi_host,
PFX "Sending CM REQ failed\n");
comp = 1;
target->status = -ECONNRESET;
break;
case IB_CM_REP_RECEIVED:
comp = 1;
srp_cm_rep_handler(cm_id, event->private_data, target);
break;
case IB_CM_REJ_RECEIVED:
shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
comp = 1;
srp_cm_rej_handler(cm_id, event, target);
break;
case IB_CM_DREQ_RECEIVED:
shost_printk(KERN_WARNING, target->scsi_host,
PFX "DREQ received - connection closed\n");
srp_change_conn_state(target, false);
if (ib_send_cm_drep(cm_id, NULL, 0))
shost_printk(KERN_ERR, target->scsi_host,
PFX "Sending CM DREP failed\n");
queue_work(system_long_wq, &target->tl_err_work);
break;
case IB_CM_TIMEWAIT_EXIT:
shost_printk(KERN_ERR, target->scsi_host,
PFX "connection closed\n");
target->status = 0;
break;
case IB_CM_MRA_RECEIVED:
case IB_CM_DREQ_ERROR:
case IB_CM_DREP_RECEIVED:
break;
default:
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Unhandled CM event %d\n", event->event);
break;
}
if (comp)
complete(&target->done);
return 0;
}
/**
* srp_change_queue_type - changing device queue tag type
* @sdev: scsi device struct
* @tag_type: requested tag type
*
* Returns queue tag type.
*/
static int
srp_change_queue_type(struct scsi_device *sdev, int tag_type)
{
if (sdev->tagged_supported) {
scsi_set_tag_type(sdev, tag_type);
if (tag_type)
scsi_activate_tcq(sdev, sdev->queue_depth);
else
scsi_deactivate_tcq(sdev, sdev->queue_depth);
} else
tag_type = 0;
return tag_type;
}
/**
* srp_change_queue_depth - setting device queue depth
* @sdev: scsi device struct
* @qdepth: requested queue depth
* @reason: SCSI_QDEPTH_DEFAULT/SCSI_QDEPTH_QFULL/SCSI_QDEPTH_RAMP_UP
* (see include/scsi/scsi_host.h for definition)
*
* Returns queue depth.
*/
static int
srp_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
{
struct Scsi_Host *shost = sdev->host;
int max_depth;
if (reason == SCSI_QDEPTH_DEFAULT || reason == SCSI_QDEPTH_RAMP_UP) {
max_depth = shost->can_queue;
if (!sdev->tagged_supported)
max_depth = 1;
if (qdepth > max_depth)
qdepth = max_depth;
scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
} else if (reason == SCSI_QDEPTH_QFULL)
scsi_track_queue_full(sdev, qdepth);
else
return -EOPNOTSUPP;
return sdev->queue_depth;
}
static int srp_send_tsk_mgmt(struct srp_target_port *target,
u64 req_tag, unsigned int lun, u8 func)
{
struct srp_rport *rport = target->rport;
struct ib_device *dev = target->srp_host->srp_dev->dev;
struct srp_iu *iu;
struct srp_tsk_mgmt *tsk_mgmt;
if (!target->connected || target->qp_in_error)
return -1;
init_completion(&target->tsk_mgmt_done);
/*
* Lock the rport mutex to avoid that srp_create_target_ib() is
* invoked while a task management function is being sent.
*/
mutex_lock(&rport->mutex);
spin_lock_irq(&target->lock);
iu = __srp_get_tx_iu(target, SRP_IU_TSK_MGMT);
spin_unlock_irq(&target->lock);
if (!iu) {
mutex_unlock(&rport->mutex);
return -1;
}
ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
DMA_TO_DEVICE);
tsk_mgmt = iu->buf;
memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
tsk_mgmt->opcode = SRP_TSK_MGMT;
tsk_mgmt->lun = cpu_to_be64((u64) lun << 48);
tsk_mgmt->tag = req_tag | SRP_TAG_TSK_MGMT;
tsk_mgmt->tsk_mgmt_func = func;
tsk_mgmt->task_tag = req_tag;
ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
DMA_TO_DEVICE);
if (srp_post_send(target, iu, sizeof *tsk_mgmt)) {
srp_put_tx_iu(target, iu, SRP_IU_TSK_MGMT);
mutex_unlock(&rport->mutex);
return -1;
}
mutex_unlock(&rport->mutex);
if (!wait_for_completion_timeout(&target->tsk_mgmt_done,
msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
return -1;
return 0;
}
static int srp_abort(struct scsi_cmnd *scmnd)
{
struct srp_target_port *target = host_to_target(scmnd->device->host);
struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
int ret;
shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
if (!req || !srp_claim_req(target, req, scmnd))
return SUCCESS;
if (srp_send_tsk_mgmt(target, req->index, scmnd->device->lun,
SRP_TSK_ABORT_TASK) == 0)
ret = SUCCESS;
else if (target->rport->state == SRP_RPORT_LOST)
ret = FAST_IO_FAIL;
else
ret = FAILED;
srp_free_req(target, req, scmnd, 0);
scmnd->result = DID_ABORT << 16;
scmnd->scsi_done(scmnd);
return ret;
}
static int srp_reset_device(struct scsi_cmnd *scmnd)
{
struct srp_target_port *target = host_to_target(scmnd->device->host);
int i;
shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
if (srp_send_tsk_mgmt(target, SRP_TAG_NO_REQ, scmnd->device->lun,
SRP_TSK_LUN_RESET))
return FAILED;
if (target->tsk_mgmt_status)
return FAILED;
for (i = 0; i < target->req_ring_size; ++i) {
struct srp_request *req = &target->req_ring[i];
if (req->scmnd && req->scmnd->device == scmnd->device)
srp_finish_req(target, req, DID_RESET << 16);
}
return SUCCESS;
}
static int srp_reset_host(struct scsi_cmnd *scmnd)
{
struct srp_target_port *target = host_to_target(scmnd->device->host);
shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
}
static int srp_slave_configure(struct scsi_device *sdev)
{
struct Scsi_Host *shost = sdev->host;
struct srp_target_port *target = host_to_target(shost);
struct request_queue *q = sdev->request_queue;
unsigned long timeout;
if (sdev->type == TYPE_DISK) {
timeout = max_t(unsigned, 30 * HZ, target->rq_tmo_jiffies);
blk_queue_rq_timeout(q, timeout);
}
return 0;
}
static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "0x%016llx\n",
(unsigned long long) be64_to_cpu(target->id_ext));
}
static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "0x%016llx\n",
(unsigned long long) be64_to_cpu(target->ioc_guid));
}
static ssize_t show_service_id(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "0x%016llx\n",
(unsigned long long) be64_to_cpu(target->service_id));
}
static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
}
static ssize_t show_sgid(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%pI6\n", target->path.sgid.raw);
}
static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%pI6\n", target->path.dgid.raw);
}
static ssize_t show_orig_dgid(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%pI6\n", target->orig_dgid);
}
static ssize_t show_req_lim(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%d\n", target->req_lim);
}
static ssize_t show_zero_req_lim(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%d\n", target->zero_req_lim);
}
static ssize_t show_local_ib_port(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%d\n", target->srp_host->port);
}
static ssize_t show_local_ib_device(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
}
static ssize_t show_comp_vector(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%d\n", target->comp_vector);
}
static ssize_t show_tl_retry_count(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%d\n", target->tl_retry_count);
}
static ssize_t show_cmd_sg_entries(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%u\n", target->cmd_sg_cnt);
}
static ssize_t show_allow_ext_sg(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct srp_target_port *target = host_to_target(class_to_shost(dev));
return sprintf(buf, "%s\n", target->allow_ext_sg ? "true" : "false");
}
static DEVICE_ATTR(id_ext, S_IRUGO, show_id_ext, NULL);
static DEVICE_ATTR(ioc_guid, S_IRUGO, show_ioc_guid, NULL);
static DEVICE_ATTR(service_id, S_IRUGO, show_service_id, NULL);
static DEVICE_ATTR(pkey, S_IRUGO, show_pkey, NULL);
static DEVICE_ATTR(sgid, S_IRUGO, show_sgid, NULL);
static DEVICE_ATTR(dgid, S_IRUGO, show_dgid, NULL);
static DEVICE_ATTR(orig_dgid, S_IRUGO, show_orig_dgid, NULL);
static DEVICE_ATTR(req_lim, S_IRUGO, show_req_lim, NULL);
static DEVICE_ATTR(zero_req_lim, S_IRUGO, show_zero_req_lim, NULL);
static DEVICE_ATTR(local_ib_port, S_IRUGO, show_local_ib_port, NULL);
static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
static DEVICE_ATTR(comp_vector, S_IRUGO, show_comp_vector, NULL);
static DEVICE_ATTR(tl_retry_count, S_IRUGO, show_tl_retry_count, NULL);
static DEVICE_ATTR(cmd_sg_entries, S_IRUGO, show_cmd_sg_entries, NULL);
static DEVICE_ATTR(allow_ext_sg, S_IRUGO, show_allow_ext_sg, NULL);
static struct device_attribute *srp_host_attrs[] = {
&dev_attr_id_ext,
&dev_attr_ioc_guid,
&dev_attr_service_id,
&dev_attr_pkey,
&dev_attr_sgid,
&dev_attr_dgid,
&dev_attr_orig_dgid,
&dev_attr_req_lim,
&dev_attr_zero_req_lim,
&dev_attr_local_ib_port,
&dev_attr_local_ib_device,
&dev_attr_comp_vector,
&dev_attr_tl_retry_count,
&dev_attr_cmd_sg_entries,
&dev_attr_allow_ext_sg,
NULL
};
static struct scsi_host_template srp_template = {
.module = THIS_MODULE,
.name = "InfiniBand SRP initiator",
.proc_name = DRV_NAME,
.slave_configure = srp_slave_configure,
.info = srp_target_info,
.queuecommand = srp_queuecommand,
.change_queue_depth = srp_change_queue_depth,
.change_queue_type = srp_change_queue_type,
.eh_abort_handler = srp_abort,
.eh_device_reset_handler = srp_reset_device,
.eh_host_reset_handler = srp_reset_host,
.skip_settle_delay = true,
.sg_tablesize = SRP_DEF_SG_TABLESIZE,
.can_queue = SRP_DEFAULT_CMD_SQ_SIZE,
.this_id = -1,
.cmd_per_lun = SRP_DEFAULT_CMD_SQ_SIZE,
.use_clustering = ENABLE_CLUSTERING,
.shost_attrs = srp_host_attrs
};
static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
{
struct srp_rport_identifiers ids;
struct srp_rport *rport;
sprintf(target->target_name, "SRP.T10:%016llX",
(unsigned long long) be64_to_cpu(target->id_ext));
if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
return -ENODEV;
memcpy(ids.port_id, &target->id_ext, 8);
memcpy(ids.port_id + 8, &target->ioc_guid, 8);
ids.roles = SRP_RPORT_ROLE_TARGET;
rport = srp_rport_add(target->scsi_host, &ids);
if (IS_ERR(rport)) {
scsi_remove_host(target->scsi_host);
return PTR_ERR(rport);
}
rport->lld_data = target;
target->rport = rport;
spin_lock(&host->target_lock);
list_add_tail(&target->list, &host->target_list);
spin_unlock(&host->target_lock);
target->state = SRP_TARGET_LIVE;
scsi_scan_target(&target->scsi_host->shost_gendev,
0, target->scsi_id, SCAN_WILD_CARD, 0);
return 0;
}
static void srp_release_dev(struct device *dev)
{
struct srp_host *host =
container_of(dev, struct srp_host, dev);
complete(&host->released);
}
static struct class srp_class = {
.name = "infiniband_srp",
.dev_release = srp_release_dev
};
/**
* srp_conn_unique() - check whether the connection to a target is unique
*/
static bool srp_conn_unique(struct srp_host *host,
struct srp_target_port *target)
{
struct srp_target_port *t;
bool ret = false;
if (target->state == SRP_TARGET_REMOVED)
goto out;
ret = true;
spin_lock(&host->target_lock);
list_for_each_entry(t, &host->target_list, list) {
if (t != target &&
target->id_ext == t->id_ext &&
target->ioc_guid == t->ioc_guid &&
target->initiator_ext == t->initiator_ext) {
ret = false;
break;
}
}
spin_unlock(&host->target_lock);
out:
return ret;
}
/*
* Target ports are added by writing
*
* id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
* pkey=<P_Key>,service_id=<service ID>
*
* to the add_target sysfs attribute.
*/
enum {
SRP_OPT_ERR = 0,
SRP_OPT_ID_EXT = 1 << 0,
SRP_OPT_IOC_GUID = 1 << 1,
SRP_OPT_DGID = 1 << 2,
SRP_OPT_PKEY = 1 << 3,
SRP_OPT_SERVICE_ID = 1 << 4,
SRP_OPT_MAX_SECT = 1 << 5,
SRP_OPT_MAX_CMD_PER_LUN = 1 << 6,
SRP_OPT_IO_CLASS = 1 << 7,
SRP_OPT_INITIATOR_EXT = 1 << 8,
SRP_OPT_CMD_SG_ENTRIES = 1 << 9,
SRP_OPT_ALLOW_EXT_SG = 1 << 10,
SRP_OPT_SG_TABLESIZE = 1 << 11,
SRP_OPT_COMP_VECTOR = 1 << 12,
SRP_OPT_TL_RETRY_COUNT = 1 << 13,
SRP_OPT_QUEUE_SIZE = 1 << 14,
SRP_OPT_ALL = (SRP_OPT_ID_EXT |
SRP_OPT_IOC_GUID |
SRP_OPT_DGID |
SRP_OPT_PKEY |
SRP_OPT_SERVICE_ID),
};
static const match_table_t srp_opt_tokens = {
{ SRP_OPT_ID_EXT, "id_ext=%s" },
{ SRP_OPT_IOC_GUID, "ioc_guid=%s" },
{ SRP_OPT_DGID, "dgid=%s" },
{ SRP_OPT_PKEY, "pkey=%x" },
{ SRP_OPT_SERVICE_ID, "service_id=%s" },
{ SRP_OPT_MAX_SECT, "max_sect=%d" },
{ SRP_OPT_MAX_CMD_PER_LUN, "max_cmd_per_lun=%d" },
{ SRP_OPT_IO_CLASS, "io_class=%x" },
{ SRP_OPT_INITIATOR_EXT, "initiator_ext=%s" },
{ SRP_OPT_CMD_SG_ENTRIES, "cmd_sg_entries=%u" },
{ SRP_OPT_ALLOW_EXT_SG, "allow_ext_sg=%u" },
{ SRP_OPT_SG_TABLESIZE, "sg_tablesize=%u" },
{ SRP_OPT_COMP_VECTOR, "comp_vector=%u" },
{ SRP_OPT_TL_RETRY_COUNT, "tl_retry_count=%u" },
{ SRP_OPT_QUEUE_SIZE, "queue_size=%d" },
{ SRP_OPT_ERR, NULL }
};
static int srp_parse_options(const char *buf, struct srp_target_port *target)
{
char *options, *sep_opt;
char *p;
char dgid[3];
substring_t args[MAX_OPT_ARGS];
int opt_mask = 0;
int token;
int ret = -EINVAL;
int i;
options = kstrdup(buf, GFP_KERNEL);
if (!options)
return -ENOMEM;
sep_opt = options;
while ((p = strsep(&sep_opt, ",")) != NULL) {
if (!*p)
continue;
token = match_token(p, srp_opt_tokens, args);
opt_mask |= token;
switch (token) {
case SRP_OPT_ID_EXT:
p = match_strdup(args);
if (!p) {
ret = -ENOMEM;
goto out;
}
target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
kfree(p);
break;
case SRP_OPT_IOC_GUID:
p = match_strdup(args);
if (!p) {
ret = -ENOMEM;
goto out;
}
target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
kfree(p);
break;
case SRP_OPT_DGID:
p = match_strdup(args);
if (!p) {
ret = -ENOMEM;
goto out;
}
if (strlen(p) != 32) {
pr_warn("bad dest GID parameter '%s'\n", p);
kfree(p);
goto out;
}
for (i = 0; i < 16; ++i) {
strlcpy(dgid, p + i * 2, 3);
target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
}
kfree(p);
memcpy(target->orig_dgid, target->path.dgid.raw, 16);
break;
case SRP_OPT_PKEY:
if (match_hex(args, &token)) {
pr_warn("bad P_Key parameter '%s'\n", p);
goto out;
}
target->path.pkey = cpu_to_be16(token);
break;
case SRP_OPT_SERVICE_ID:
p = match_strdup(args);
if (!p) {
ret = -ENOMEM;
goto out;
}
target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
target->path.service_id = target->service_id;
kfree(p);
break;
case SRP_OPT_MAX_SECT:
if (match_int(args, &token)) {
pr_warn("bad max sect parameter '%s'\n", p);
goto out;
}
target->scsi_host->max_sectors = token;
break;
case SRP_OPT_QUEUE_SIZE:
if (match_int(args, &token) || token < 1) {
pr_warn("bad queue_size parameter '%s'\n", p);
goto out;
}
target->scsi_host->can_queue = token;
target->queue_size = token + SRP_RSP_SQ_SIZE +
SRP_TSK_MGMT_SQ_SIZE;
if (!(opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
target->scsi_host->cmd_per_lun = token;
break;
case SRP_OPT_MAX_CMD_PER_LUN:
if (match_int(args, &token) || token < 1) {
pr_warn("bad max cmd_per_lun parameter '%s'\n",
p);
goto out;
}
target->scsi_host->cmd_per_lun = token;
break;
case SRP_OPT_IO_CLASS:
if (match_hex(args, &token)) {
pr_warn("bad IO class parameter '%s'\n", p);
goto out;
}
if (token != SRP_REV10_IB_IO_CLASS &&
token != SRP_REV16A_IB_IO_CLASS) {
pr_warn("unknown IO class parameter value %x specified (use %x or %x).\n",
token, SRP_REV10_IB_IO_CLASS,
SRP_REV16A_IB_IO_CLASS);
goto out;
}
target->io_class = token;
break;
case SRP_OPT_INITIATOR_EXT:
p = match_strdup(args);
if (!p) {
ret = -ENOMEM;
goto out;
}
target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
kfree(p);
break;
case SRP_OPT_CMD_SG_ENTRIES:
if (match_int(args, &token) || token < 1 || token > 255) {
pr_warn("bad max cmd_sg_entries parameter '%s'\n",
p);
goto out;
}
target->cmd_sg_cnt = token;
break;
case SRP_OPT_ALLOW_EXT_SG:
if (match_int(args, &token)) {
pr_warn("bad allow_ext_sg parameter '%s'\n", p);
goto out;
}
target->allow_ext_sg = !!token;
break;
case SRP_OPT_SG_TABLESIZE:
if (match_int(args, &token) || token < 1 ||
token > SCSI_MAX_SG_CHAIN_SEGMENTS) {
pr_warn("bad max sg_tablesize parameter '%s'\n",
p);
goto out;
}
target->sg_tablesize = token;
break;
case SRP_OPT_COMP_VECTOR:
if (match_int(args, &token) || token < 0) {
pr_warn("bad comp_vector parameter '%s'\n", p);
goto out;
}
target->comp_vector = token;
break;
case SRP_OPT_TL_RETRY_COUNT:
if (match_int(args, &token) || token < 2 || token > 7) {
pr_warn("bad tl_retry_count parameter '%s' (must be a number between 2 and 7)\n",
p);
goto out;
}
target->tl_retry_count = token;
break;
default:
pr_warn("unknown parameter or missing value '%s' in target creation request\n",
p);
goto out;
}
}
if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
ret = 0;
else
for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
!(srp_opt_tokens[i].token & opt_mask))
pr_warn("target creation request is missing parameter '%s'\n",
srp_opt_tokens[i].pattern);
if (target->scsi_host->cmd_per_lun > target->scsi_host->can_queue
&& (opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
pr_warn("cmd_per_lun = %d > queue_size = %d\n",
target->scsi_host->cmd_per_lun,
target->scsi_host->can_queue);
out:
kfree(options);
return ret;
}
static ssize_t srp_create_target(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct srp_host *host =
container_of(dev, struct srp_host, dev);
struct Scsi_Host *target_host;
struct srp_target_port *target;
struct ib_device *ibdev = host->srp_dev->dev;
int ret;
target_host = scsi_host_alloc(&srp_template,
sizeof (struct srp_target_port));
if (!target_host)
return -ENOMEM;
target_host->transportt = ib_srp_transport_template;
target_host->max_channel = 0;
target_host->max_id = 1;
target_host->max_lun = SRP_MAX_LUN;
target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
target = host_to_target(target_host);
target->io_class = SRP_REV16A_IB_IO_CLASS;
target->scsi_host = target_host;
target->srp_host = host;
target->lkey = host->srp_dev->mr->lkey;
target->rkey = host->srp_dev->mr->rkey;
target->cmd_sg_cnt = cmd_sg_entries;
target->sg_tablesize = indirect_sg_entries ? : cmd_sg_entries;
target->allow_ext_sg = allow_ext_sg;
target->tl_retry_count = 7;
target->queue_size = SRP_DEFAULT_QUEUE_SIZE;
ret = srp_parse_options(buf, target);
if (ret)
goto err;
target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;
if (!srp_conn_unique(target->srp_host, target)) {
shost_printk(KERN_INFO, target->scsi_host,
PFX "Already connected to target port with id_ext=%016llx;ioc_guid=%016llx;initiator_ext=%016llx\n",
be64_to_cpu(target->id_ext),
be64_to_cpu(target->ioc_guid),
be64_to_cpu(target->initiator_ext));
ret = -EEXIST;
goto err;
}
if (!host->srp_dev->fmr_pool && !target->allow_ext_sg &&
target->cmd_sg_cnt < target->sg_tablesize) {
pr_warn("No FMR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
target->sg_tablesize = target->cmd_sg_cnt;
}
target_host->sg_tablesize = target->sg_tablesize;
target->indirect_size = target->sg_tablesize *
sizeof (struct srp_direct_buf);
target->max_iu_len = sizeof (struct srp_cmd) +
sizeof (struct srp_indirect_buf) +
target->cmd_sg_cnt * sizeof (struct srp_direct_buf);
INIT_WORK(&target->tl_err_work, srp_tl_err_work);
INIT_WORK(&target->remove_work, srp_remove_work);
spin_lock_init(&target->lock);
INIT_LIST_HEAD(&target->free_tx);
ret = srp_alloc_req_data(target);
if (ret)
goto err_free_mem;
ret = ib_query_gid(ibdev, host->port, 0, &target->path.sgid);
if (ret)
goto err_free_mem;
shost_printk(KERN_DEBUG, target->scsi_host, PFX
"new target: id_ext %016llx ioc_guid %016llx pkey %04x "
"service_id %016llx dgid %pI6\n",
(unsigned long long) be64_to_cpu(target->id_ext),
(unsigned long long) be64_to_cpu(target->ioc_guid),
be16_to_cpu(target->path.pkey),
(unsigned long long) be64_to_cpu(target->service_id),
target->path.dgid.raw);
ret = srp_create_target_ib(target);
if (ret)
goto err_free_mem;
ret = srp_new_cm_id(target);
if (ret)
goto err_free_ib;
ret = srp_connect_target(target);
if (ret) {
shost_printk(KERN_ERR, target->scsi_host,
PFX "Connection failed\n");
goto err_cm_id;
}
ret = srp_add_target(host, target);
if (ret)
goto err_disconnect;
return count;
err_disconnect:
srp_disconnect_target(target);
err_cm_id:
ib_destroy_cm_id(target->cm_id);
err_free_ib:
srp_free_target_ib(target);
err_free_mem:
srp_free_req_data(target);
err:
scsi_host_put(target_host);
return ret;
}
static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct srp_host *host = container_of(dev, struct srp_host, dev);
return sprintf(buf, "%s\n", host->srp_dev->dev->name);
}
static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
static ssize_t show_port(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct srp_host *host = container_of(dev, struct srp_host, dev);
return sprintf(buf, "%d\n", host->port);
}
static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
{
struct srp_host *host;
host = kzalloc(sizeof *host, GFP_KERNEL);
if (!host)
return NULL;
INIT_LIST_HEAD(&host->target_list);
spin_lock_init(&host->target_lock);
init_completion(&host->released);
host->srp_dev = device;
host->port = port;
host->dev.class = &srp_class;
host->dev.parent = device->dev->dma_device;
dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
if (device_register(&host->dev))
goto free_host;
if (device_create_file(&host->dev, &dev_attr_add_target))
goto err_class;
if (device_create_file(&host->dev, &dev_attr_ibdev))
goto err_class;
if (device_create_file(&host->dev, &dev_attr_port))
goto err_class;
return host;
err_class:
device_unregister(&host->dev);
free_host:
kfree(host);
return NULL;
}
static void srp_add_one(struct ib_device *device)
{
struct srp_device *srp_dev;
struct ib_device_attr *dev_attr;
struct ib_fmr_pool_param fmr_param;
struct srp_host *host;
int max_pages_per_fmr, fmr_page_shift, s, e, p;
dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
if (!dev_attr)
return;
if (ib_query_device(device, dev_attr)) {
pr_warn("Query device failed for %s\n", device->name);
goto free_attr;
}
srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
if (!srp_dev)
goto free_attr;
/*
* Use the smallest page size supported by the HCA, down to a
* minimum of 4096 bytes. We're unlikely to build large sglists
* out of smaller entries.
*/
fmr_page_shift = max(12, ffs(dev_attr->page_size_cap) - 1);
srp_dev->fmr_page_size = 1 << fmr_page_shift;
srp_dev->fmr_page_mask = ~((u64) srp_dev->fmr_page_size - 1);
srp_dev->fmr_max_size = srp_dev->fmr_page_size * SRP_FMR_SIZE;
INIT_LIST_HEAD(&srp_dev->dev_list);
srp_dev->dev = device;
srp_dev->pd = ib_alloc_pd(device);
if (IS_ERR(srp_dev->pd))
goto free_dev;
srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
IB_ACCESS_LOCAL_WRITE |
IB_ACCESS_REMOTE_READ |
IB_ACCESS_REMOTE_WRITE);
if (IS_ERR(srp_dev->mr))
goto err_pd;
for (max_pages_per_fmr = SRP_FMR_SIZE;
max_pages_per_fmr >= SRP_FMR_MIN_SIZE;
max_pages_per_fmr /= 2, srp_dev->fmr_max_size /= 2) {
memset(&fmr_param, 0, sizeof fmr_param);
fmr_param.pool_size = SRP_FMR_POOL_SIZE;
fmr_param.dirty_watermark = SRP_FMR_DIRTY_SIZE;
fmr_param.cache = 1;
fmr_param.max_pages_per_fmr = max_pages_per_fmr;
fmr_param.page_shift = fmr_page_shift;
fmr_param.access = (IB_ACCESS_LOCAL_WRITE |
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_REMOTE_READ);
srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
if (!IS_ERR(srp_dev->fmr_pool))
break;
}
if (IS_ERR(srp_dev->fmr_pool))
srp_dev->fmr_pool = NULL;
if (device->node_type == RDMA_NODE_IB_SWITCH) {
s = 0;
e = 0;
} else {
s = 1;
e = device->phys_port_cnt;
}
for (p = s; p <= e; ++p) {
host = srp_add_port(srp_dev, p);
if (host)
list_add_tail(&host->list, &srp_dev->dev_list);
}
ib_set_client_data(device, &srp_client, srp_dev);
goto free_attr;
err_pd:
ib_dealloc_pd(srp_dev->pd);
free_dev:
kfree(srp_dev);
free_attr:
kfree(dev_attr);
}
static void srp_remove_one(struct ib_device *device)
{
struct srp_device *srp_dev;
struct srp_host *host, *tmp_host;
struct srp_target_port *target;
srp_dev = ib_get_client_data(device, &srp_client);
if (!srp_dev)
return;
list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
device_unregister(&host->dev);
/*
* Wait for the sysfs entry to go away, so that no new
* target ports can be created.
*/
wait_for_completion(&host->released);
/*
* Remove all target ports.
*/
spin_lock(&host->target_lock);
list_for_each_entry(target, &host->target_list, list)
srp_queue_remove_work(target);
spin_unlock(&host->target_lock);
/*
* Wait for target port removal tasks.
*/
flush_workqueue(system_long_wq);
kfree(host);
}
if (srp_dev->fmr_pool)
ib_destroy_fmr_pool(srp_dev->fmr_pool);
ib_dereg_mr(srp_dev->mr);
ib_dealloc_pd(srp_dev->pd);
kfree(srp_dev);
}
static struct srp_function_template ib_srp_transport_functions = {
.has_rport_state = true,
.reset_timer_if_blocked = true,
.reconnect_delay = &srp_reconnect_delay,
.fast_io_fail_tmo = &srp_fast_io_fail_tmo,
.dev_loss_tmo = &srp_dev_loss_tmo,
.reconnect = srp_rport_reconnect,
.rport_delete = srp_rport_delete,
.terminate_rport_io = srp_terminate_io,
};
static int __init srp_init_module(void)
{
int ret;
BUILD_BUG_ON(FIELD_SIZEOF(struct ib_wc, wr_id) < sizeof(void *));
if (srp_sg_tablesize) {
pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
if (!cmd_sg_entries)
cmd_sg_entries = srp_sg_tablesize;
}
if (!cmd_sg_entries)
cmd_sg_entries = SRP_DEF_SG_TABLESIZE;
if (cmd_sg_entries > 255) {
pr_warn("Clamping cmd_sg_entries to 255\n");
cmd_sg_entries = 255;
}
if (!indirect_sg_entries)
indirect_sg_entries = cmd_sg_entries;
else if (indirect_sg_entries < cmd_sg_entries) {
pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
cmd_sg_entries);
indirect_sg_entries = cmd_sg_entries;
}
ib_srp_transport_template =
srp_attach_transport(&ib_srp_transport_functions);
if (!ib_srp_transport_template)
return -ENOMEM;
ret = class_register(&srp_class);
if (ret) {
pr_err("couldn't register class infiniband_srp\n");
srp_release_transport(ib_srp_transport_template);
return ret;
}
ib_sa_register_client(&srp_sa_client);
ret = ib_register_client(&srp_client);
if (ret) {
pr_err("couldn't register IB client\n");
srp_release_transport(ib_srp_transport_template);
ib_sa_unregister_client(&srp_sa_client);
class_unregister(&srp_class);
return ret;
}
return 0;
}
static void __exit srp_cleanup_module(void)
{
ib_unregister_client(&srp_client);
ib_sa_unregister_client(&srp_sa_client);
class_unregister(&srp_class);
srp_release_transport(ib_srp_transport_template);
}
module_init(srp_init_module);
module_exit(srp_cleanup_module);