Commit 3a85a5de authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe

nvme-loop: add a NVMe loopback host driver

This patch implements adds nvme-loop which allows to access local devices
exported as NVMe over Fabrics namespaces. This module can be useful for
easy evaluation, testing and also feature experimentation.

To createa nvme-loop device you need to configure the NVMe target to
export a loop port (see the nvmetcli documentaton for that) and then
connect to it using

	nvme connect-all -t loop

which requires the very latest nvme-cli version with Fabrics support.
Signed-off-by: default avatarJay Freyensee <james.p.freyensee@intel.com>
Signed-off-by: default avatarMing Lin <ming.l@ssi.samsung.com>
Signed-off-by: default avatarSagi Grimberg <sagi@grimberg.me>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarSteve Wise <swise@opengridcomputing.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent a07b4970
......@@ -13,4 +13,14 @@ config NVME_TARGET
To configure the NVMe target you probably want to use the nvmetcli
tool from http://git.infradead.org/users/hch/nvmetcli.git.
config NVME_TARGET_LOOP
tristate "NVMe loopback device support"
depends on BLK_DEV_NVME
select NVME_TARGET
select NVME_FABRICS
select SG_POOL
help
This enables the NVMe loopback device support, which can be useful
to test NVMe host and target side features.
If unsure, say N.
obj-$(CONFIG_NVME_TARGET) += nvmet.o
obj-$(CONFIG_NVME_TARGET_LOOP) += nvme-loop.o
nvmet-y += core.o configfs.o admin-cmd.o io-cmd.o fabrics-cmd.o \
discovery.o
nvme-loop-y += loop.o
/*
* NVMe over Fabrics loopback device.
* Copyright (c) 2015-2016 HGST, a Western Digital Company.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/scatterlist.h>
#include <linux/delay.h>
#include <linux/blk-mq.h>
#include <linux/nvme.h>
#include <linux/module.h>
#include <linux/parser.h>
#include <linux/t10-pi.h>
#include "nvmet.h"
#include "../host/nvme.h"
#include "../host/fabrics.h"
#define NVME_LOOP_AQ_DEPTH 256
#define NVME_LOOP_MAX_SEGMENTS 256
/*
* We handle AEN commands ourselves and don't even let the
* block layer know about them.
*/
#define NVME_LOOP_NR_AEN_COMMANDS 1
#define NVME_LOOP_AQ_BLKMQ_DEPTH \
(NVME_LOOP_AQ_DEPTH - NVME_LOOP_NR_AEN_COMMANDS)
struct nvme_loop_iod {
struct nvme_command cmd;
struct nvme_completion rsp;
struct nvmet_req req;
struct nvme_loop_queue *queue;
struct work_struct work;
struct sg_table sg_table;
struct scatterlist first_sgl[];
};
struct nvme_loop_ctrl {
spinlock_t lock;
struct nvme_loop_queue *queues;
u32 queue_count;
struct blk_mq_tag_set admin_tag_set;
struct list_head list;
u64 cap;
struct blk_mq_tag_set tag_set;
struct nvme_loop_iod async_event_iod;
struct nvme_ctrl ctrl;
struct nvmet_ctrl *target_ctrl;
struct work_struct delete_work;
struct work_struct reset_work;
};
static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl)
{
return container_of(ctrl, struct nvme_loop_ctrl, ctrl);
}
struct nvme_loop_queue {
struct nvmet_cq nvme_cq;
struct nvmet_sq nvme_sq;
struct nvme_loop_ctrl *ctrl;
};
static struct nvmet_port *nvmet_loop_port;
static LIST_HEAD(nvme_loop_ctrl_list);
static DEFINE_MUTEX(nvme_loop_ctrl_mutex);
static void nvme_loop_queue_response(struct nvmet_req *nvme_req);
static void nvme_loop_delete_ctrl(struct nvmet_ctrl *ctrl);
static struct nvmet_fabrics_ops nvme_loop_ops;
static inline int nvme_loop_queue_idx(struct nvme_loop_queue *queue)
{
return queue - queue->ctrl->queues;
}
static void nvme_loop_complete_rq(struct request *req)
{
struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req);
int error = 0;
nvme_cleanup_cmd(req);
sg_free_table_chained(&iod->sg_table, true);
if (unlikely(req->errors)) {
if (nvme_req_needs_retry(req, req->errors)) {
nvme_requeue_req(req);
return;
}
if (req->cmd_type == REQ_TYPE_DRV_PRIV)
error = req->errors;
else
error = nvme_error_status(req->errors);
}
blk_mq_end_request(req, error);
}
static void nvme_loop_queue_response(struct nvmet_req *nvme_req)
{
struct nvme_loop_iod *iod =
container_of(nvme_req, struct nvme_loop_iod, req);
struct nvme_completion *cqe = &iod->rsp;
/*
* AEN requests are special as they don't time out and can
* survive any kind of queue freeze and often don't respond to
* aborts. We don't even bother to allocate a struct request
* for them but rather special case them here.
*/
if (unlikely(nvme_loop_queue_idx(iod->queue) == 0 &&
cqe->command_id >= NVME_LOOP_AQ_BLKMQ_DEPTH)) {
nvme_complete_async_event(&iod->queue->ctrl->ctrl, cqe);
} else {
struct request *req = blk_mq_rq_from_pdu(iod);
if (req->cmd_type == REQ_TYPE_DRV_PRIV && req->special)
memcpy(req->special, cqe, sizeof(*cqe));
blk_mq_complete_request(req, le16_to_cpu(cqe->status) >> 1);
}
}
static void nvme_loop_execute_work(struct work_struct *work)
{
struct nvme_loop_iod *iod =
container_of(work, struct nvme_loop_iod, work);
iod->req.execute(&iod->req);
}
static enum blk_eh_timer_return
nvme_loop_timeout(struct request *rq, bool reserved)
{
struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(rq);
/* queue error recovery */
schedule_work(&iod->queue->ctrl->reset_work);
/* fail with DNR on admin cmd timeout */
rq->errors = NVME_SC_ABORT_REQ | NVME_SC_DNR;
return BLK_EH_HANDLED;
}
static int nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct nvme_ns *ns = hctx->queue->queuedata;
struct nvme_loop_queue *queue = hctx->driver_data;
struct request *req = bd->rq;
struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req);
int ret;
ret = nvme_setup_cmd(ns, req, &iod->cmd);
if (ret)
return ret;
iod->cmd.common.flags |= NVME_CMD_SGL_METABUF;
iod->req.port = nvmet_loop_port;
if (!nvmet_req_init(&iod->req, &queue->nvme_cq,
&queue->nvme_sq, &nvme_loop_ops)) {
nvme_cleanup_cmd(req);
blk_mq_start_request(req);
nvme_loop_queue_response(&iod->req);
return 0;
}
if (blk_rq_bytes(req)) {
iod->sg_table.sgl = iod->first_sgl;
ret = sg_alloc_table_chained(&iod->sg_table,
req->nr_phys_segments, iod->sg_table.sgl);
if (ret)
return BLK_MQ_RQ_QUEUE_BUSY;
iod->req.sg = iod->sg_table.sgl;
iod->req.sg_cnt = blk_rq_map_sg(req->q, req, iod->sg_table.sgl);
BUG_ON(iod->req.sg_cnt > req->nr_phys_segments);
}
iod->cmd.common.command_id = req->tag;
blk_mq_start_request(req);
schedule_work(&iod->work);
return 0;
}
static void nvme_loop_submit_async_event(struct nvme_ctrl *arg, int aer_idx)
{
struct nvme_loop_ctrl *ctrl = to_loop_ctrl(arg);
struct nvme_loop_queue *queue = &ctrl->queues[0];
struct nvme_loop_iod *iod = &ctrl->async_event_iod;
memset(&iod->cmd, 0, sizeof(iod->cmd));
iod->cmd.common.opcode = nvme_admin_async_event;
iod->cmd.common.command_id = NVME_LOOP_AQ_BLKMQ_DEPTH;
iod->cmd.common.flags |= NVME_CMD_SGL_METABUF;
if (!nvmet_req_init(&iod->req, &queue->nvme_cq, &queue->nvme_sq,
&nvme_loop_ops)) {
dev_err(ctrl->ctrl.device, "failed async event work\n");
return;
}
schedule_work(&iod->work);
}
static int nvme_loop_init_iod(struct nvme_loop_ctrl *ctrl,
struct nvme_loop_iod *iod, unsigned int queue_idx)
{
BUG_ON(queue_idx >= ctrl->queue_count);
iod->req.cmd = &iod->cmd;
iod->req.rsp = &iod->rsp;
iod->queue = &ctrl->queues[queue_idx];
INIT_WORK(&iod->work, nvme_loop_execute_work);
return 0;
}
static int nvme_loop_init_request(void *data, struct request *req,
unsigned int hctx_idx, unsigned int rq_idx,
unsigned int numa_node)
{
return nvme_loop_init_iod(data, blk_mq_rq_to_pdu(req), hctx_idx + 1);
}
static int nvme_loop_init_admin_request(void *data, struct request *req,
unsigned int hctx_idx, unsigned int rq_idx,
unsigned int numa_node)
{
return nvme_loop_init_iod(data, blk_mq_rq_to_pdu(req), 0);
}
static int nvme_loop_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
unsigned int hctx_idx)
{
struct nvme_loop_ctrl *ctrl = data;
struct nvme_loop_queue *queue = &ctrl->queues[hctx_idx + 1];
BUG_ON(hctx_idx >= ctrl->queue_count);
hctx->driver_data = queue;
return 0;
}
static int nvme_loop_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
unsigned int hctx_idx)
{
struct nvme_loop_ctrl *ctrl = data;
struct nvme_loop_queue *queue = &ctrl->queues[0];
BUG_ON(hctx_idx != 0);
hctx->driver_data = queue;
return 0;
}
static struct blk_mq_ops nvme_loop_mq_ops = {
.queue_rq = nvme_loop_queue_rq,
.complete = nvme_loop_complete_rq,
.map_queue = blk_mq_map_queue,
.init_request = nvme_loop_init_request,
.init_hctx = nvme_loop_init_hctx,
.timeout = nvme_loop_timeout,
};
static struct blk_mq_ops nvme_loop_admin_mq_ops = {
.queue_rq = nvme_loop_queue_rq,
.complete = nvme_loop_complete_rq,
.map_queue = blk_mq_map_queue,
.init_request = nvme_loop_init_admin_request,
.init_hctx = nvme_loop_init_admin_hctx,
.timeout = nvme_loop_timeout,
};
static void nvme_loop_destroy_admin_queue(struct nvme_loop_ctrl *ctrl)
{
blk_cleanup_queue(ctrl->ctrl.admin_q);
blk_mq_free_tag_set(&ctrl->admin_tag_set);
nvmet_sq_destroy(&ctrl->queues[0].nvme_sq);
}
static void nvme_loop_free_ctrl(struct nvme_ctrl *nctrl)
{
struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl);
if (list_empty(&ctrl->list))
goto free_ctrl;
mutex_lock(&nvme_loop_ctrl_mutex);
list_del(&ctrl->list);
mutex_unlock(&nvme_loop_ctrl_mutex);
if (nctrl->tagset) {
blk_cleanup_queue(ctrl->ctrl.connect_q);
blk_mq_free_tag_set(&ctrl->tag_set);
}
kfree(ctrl->queues);
nvmf_free_options(nctrl->opts);
free_ctrl:
kfree(ctrl);
}
static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl)
{
int error;
memset(&ctrl->admin_tag_set, 0, sizeof(ctrl->admin_tag_set));
ctrl->admin_tag_set.ops = &nvme_loop_admin_mq_ops;
ctrl->admin_tag_set.queue_depth = NVME_LOOP_AQ_BLKMQ_DEPTH;
ctrl->admin_tag_set.reserved_tags = 2; /* connect + keep-alive */
ctrl->admin_tag_set.numa_node = NUMA_NO_NODE;
ctrl->admin_tag_set.cmd_size = sizeof(struct nvme_loop_iod) +
SG_CHUNK_SIZE * sizeof(struct scatterlist);
ctrl->admin_tag_set.driver_data = ctrl;
ctrl->admin_tag_set.nr_hw_queues = 1;
ctrl->admin_tag_set.timeout = ADMIN_TIMEOUT;
ctrl->queues[0].ctrl = ctrl;
error = nvmet_sq_init(&ctrl->queues[0].nvme_sq);
if (error)
return error;
ctrl->queue_count = 1;
error = blk_mq_alloc_tag_set(&ctrl->admin_tag_set);
if (error)
goto out_free_sq;
ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set);
if (IS_ERR(ctrl->ctrl.admin_q)) {
error = PTR_ERR(ctrl->ctrl.admin_q);
goto out_free_tagset;
}
error = nvmf_connect_admin_queue(&ctrl->ctrl);
if (error)
goto out_cleanup_queue;
error = nvmf_reg_read64(&ctrl->ctrl, NVME_REG_CAP, &ctrl->cap);
if (error) {
dev_err(ctrl->ctrl.device,
"prop_get NVME_REG_CAP failed\n");
goto out_cleanup_queue;
}
ctrl->ctrl.sqsize =
min_t(int, NVME_CAP_MQES(ctrl->cap) + 1, ctrl->ctrl.sqsize);
error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap);
if (error)
goto out_cleanup_queue;
ctrl->ctrl.max_hw_sectors =
(NVME_LOOP_MAX_SEGMENTS - 1) << (PAGE_SHIFT - 9);
error = nvme_init_identify(&ctrl->ctrl);
if (error)
goto out_cleanup_queue;
nvme_start_keep_alive(&ctrl->ctrl);
return 0;
out_cleanup_queue:
blk_cleanup_queue(ctrl->ctrl.admin_q);
out_free_tagset:
blk_mq_free_tag_set(&ctrl->admin_tag_set);
out_free_sq:
nvmet_sq_destroy(&ctrl->queues[0].nvme_sq);
return error;
}
static void nvme_loop_shutdown_ctrl(struct nvme_loop_ctrl *ctrl)
{
int i;
nvme_stop_keep_alive(&ctrl->ctrl);
if (ctrl->queue_count > 1) {
nvme_stop_queues(&ctrl->ctrl);
blk_mq_tagset_busy_iter(&ctrl->tag_set,
nvme_cancel_request, &ctrl->ctrl);
for (i = 1; i < ctrl->queue_count; i++)
nvmet_sq_destroy(&ctrl->queues[i].nvme_sq);
}
if (ctrl->ctrl.state == NVME_CTRL_LIVE)
nvme_shutdown_ctrl(&ctrl->ctrl);
blk_mq_stop_hw_queues(ctrl->ctrl.admin_q);
blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
nvme_cancel_request, &ctrl->ctrl);
nvme_loop_destroy_admin_queue(ctrl);
}
static void nvme_loop_del_ctrl_work(struct work_struct *work)
{
struct nvme_loop_ctrl *ctrl = container_of(work,
struct nvme_loop_ctrl, delete_work);
nvme_remove_namespaces(&ctrl->ctrl);
nvme_loop_shutdown_ctrl(ctrl);
nvme_uninit_ctrl(&ctrl->ctrl);
nvme_put_ctrl(&ctrl->ctrl);
}
static int __nvme_loop_del_ctrl(struct nvme_loop_ctrl *ctrl)
{
if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING))
return -EBUSY;
if (!schedule_work(&ctrl->delete_work))
return -EBUSY;
return 0;
}
static int nvme_loop_del_ctrl(struct nvme_ctrl *nctrl)
{
struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl);
int ret;
ret = __nvme_loop_del_ctrl(ctrl);
if (ret)
return ret;
flush_work(&ctrl->delete_work);
return 0;
}
static void nvme_loop_delete_ctrl(struct nvmet_ctrl *nctrl)
{
struct nvme_loop_ctrl *ctrl;
mutex_lock(&nvme_loop_ctrl_mutex);
list_for_each_entry(ctrl, &nvme_loop_ctrl_list, list) {
if (ctrl->ctrl.cntlid == nctrl->cntlid)
__nvme_loop_del_ctrl(ctrl);
}
mutex_unlock(&nvme_loop_ctrl_mutex);
}
static void nvme_loop_reset_ctrl_work(struct work_struct *work)
{
struct nvme_loop_ctrl *ctrl = container_of(work,
struct nvme_loop_ctrl, reset_work);
bool changed;
int i, ret;
nvme_loop_shutdown_ctrl(ctrl);
ret = nvme_loop_configure_admin_queue(ctrl);
if (ret)
goto out_disable;
for (i = 1; i <= ctrl->ctrl.opts->nr_io_queues; i++) {
ctrl->queues[i].ctrl = ctrl;
ret = nvmet_sq_init(&ctrl->queues[i].nvme_sq);
if (ret)
goto out_free_queues;
ctrl->queue_count++;
}
for (i = 1; i <= ctrl->ctrl.opts->nr_io_queues; i++) {
ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
if (ret)
goto out_free_queues;
}
changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
WARN_ON_ONCE(!changed);
nvme_queue_scan(&ctrl->ctrl);
nvme_queue_async_events(&ctrl->ctrl);
nvme_start_queues(&ctrl->ctrl);
return;
out_free_queues:
for (i = 1; i < ctrl->queue_count; i++)
nvmet_sq_destroy(&ctrl->queues[i].nvme_sq);
nvme_loop_destroy_admin_queue(ctrl);
out_disable:
dev_warn(ctrl->ctrl.device, "Removing after reset failure\n");
nvme_remove_namespaces(&ctrl->ctrl);
nvme_uninit_ctrl(&ctrl->ctrl);
nvme_put_ctrl(&ctrl->ctrl);
}
static int nvme_loop_reset_ctrl(struct nvme_ctrl *nctrl)
{
struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl);
if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RESETTING))
return -EBUSY;
if (!schedule_work(&ctrl->reset_work))
return -EBUSY;
flush_work(&ctrl->reset_work);
return 0;
}
static const struct nvme_ctrl_ops nvme_loop_ctrl_ops = {
.name = "loop",
.module = THIS_MODULE,
.is_fabrics = true,
.reg_read32 = nvmf_reg_read32,
.reg_read64 = nvmf_reg_read64,
.reg_write32 = nvmf_reg_write32,
.reset_ctrl = nvme_loop_reset_ctrl,
.free_ctrl = nvme_loop_free_ctrl,
.submit_async_event = nvme_loop_submit_async_event,
.delete_ctrl = nvme_loop_del_ctrl,
.get_subsysnqn = nvmf_get_subsysnqn,
};
static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl)
{
struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
int ret, i;
ret = nvme_set_queue_count(&ctrl->ctrl, &opts->nr_io_queues);
if (ret || !opts->nr_io_queues)
return ret;
dev_info(ctrl->ctrl.device, "creating %d I/O queues.\n",
opts->nr_io_queues);
for (i = 1; i <= opts->nr_io_queues; i++) {
ctrl->queues[i].ctrl = ctrl;
ret = nvmet_sq_init(&ctrl->queues[i].nvme_sq);
if (ret)
goto out_destroy_queues;
ctrl->queue_count++;
}
memset(&ctrl->tag_set, 0, sizeof(ctrl->tag_set));
ctrl->tag_set.ops = &nvme_loop_mq_ops;
ctrl->tag_set.queue_depth = ctrl->ctrl.sqsize;
ctrl->tag_set.reserved_tags = 1; /* fabric connect */
ctrl->tag_set.numa_node = NUMA_NO_NODE;
ctrl->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
ctrl->tag_set.cmd_size = sizeof(struct nvme_loop_iod) +
SG_CHUNK_SIZE * sizeof(struct scatterlist);
ctrl->tag_set.driver_data = ctrl;
ctrl->tag_set.nr_hw_queues = ctrl->queue_count - 1;
ctrl->tag_set.timeout = NVME_IO_TIMEOUT;
ctrl->ctrl.tagset = &ctrl->tag_set;
ret = blk_mq_alloc_tag_set(&ctrl->tag_set);
if (ret)
goto out_destroy_queues;
ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set);
if (IS_ERR(ctrl->ctrl.connect_q)) {
ret = PTR_ERR(ctrl->ctrl.connect_q);
goto out_free_tagset;
}
for (i = 1; i <= opts->nr_io_queues; i++) {
ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
if (ret)
goto out_cleanup_connect_q;
}
return 0;
out_cleanup_connect_q:
blk_cleanup_queue(ctrl->ctrl.connect_q);
out_free_tagset:
blk_mq_free_tag_set(&ctrl->tag_set);
out_destroy_queues:
for (i = 1; i < ctrl->queue_count; i++)
nvmet_sq_destroy(&ctrl->queues[i].nvme_sq);
return ret;
}
static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
struct nvmf_ctrl_options *opts)
{
struct nvme_loop_ctrl *ctrl;
bool changed;
int ret;
ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
if (!ctrl)
return ERR_PTR(-ENOMEM);
ctrl->ctrl.opts = opts;
INIT_LIST_HEAD(&ctrl->list);
INIT_WORK(&ctrl->delete_work, nvme_loop_del_ctrl_work);
INIT_WORK(&ctrl->reset_work, nvme_loop_reset_ctrl_work);
ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops,
0 /* no quirks, we're perfect! */);
if (ret)
goto out_put_ctrl;
spin_lock_init(&ctrl->lock);
ret = -ENOMEM;
ctrl->ctrl.sqsize = opts->queue_size;
ctrl->ctrl.kato = opts->kato;
ctrl->queues = kcalloc(opts->nr_io_queues + 1, sizeof(*ctrl->queues),
GFP_KERNEL);
if (!ctrl->queues)
goto out_uninit_ctrl;
ret = nvme_loop_configure_admin_queue(ctrl);
if (ret)
goto out_free_queues;
if (opts->queue_size > ctrl->ctrl.maxcmd) {
/* warn if maxcmd is lower than queue_size */
dev_warn(ctrl->ctrl.device,
"queue_size %zu > ctrl maxcmd %u, clamping down\n",
opts->queue_size, ctrl->ctrl.maxcmd);
opts->queue_size = ctrl->ctrl.maxcmd;
}
if (opts->nr_io_queues) {
ret = nvme_loop_create_io_queues(ctrl);
if (ret)
goto out_remove_admin_queue;
}
nvme_loop_init_iod(ctrl, &ctrl->async_event_iod, 0);
dev_info(ctrl->ctrl.device,
"new ctrl: \"%s\"\n", ctrl->ctrl.opts->subsysnqn);
kref_get(&ctrl->ctrl.kref);
changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
WARN_ON_ONCE(!changed);
mutex_lock(&nvme_loop_ctrl_mutex);
list_add_tail(&ctrl->list, &nvme_loop_ctrl_list);
mutex_unlock(&nvme_loop_ctrl_mutex);
if (opts->nr_io_queues) {
nvme_queue_scan(&ctrl->ctrl);
nvme_queue_async_events(&ctrl->ctrl);
}
return &ctrl->ctrl;
out_remove_admin_queue:
nvme_loop_destroy_admin_queue(ctrl);
out_free_queues:
kfree(ctrl->queues);
out_uninit_ctrl:
nvme_uninit_ctrl(&ctrl->ctrl);
out_put_ctrl:
nvme_put_ctrl(&ctrl->ctrl);
if (ret > 0)
ret = -EIO;
return ERR_PTR(ret);
}
static int nvme_loop_add_port(struct nvmet_port *port)
{
/*
* XXX: disalow adding more than one port so
* there is no connection rejections when a
* a subsystem is assigned to a port for which
* loop doesn't have a pointer.
* This scenario would be possible if we allowed
* more than one port to be added and a subsystem
* was assigned to a port other than nvmet_loop_port.
*/
if (nvmet_loop_port)
return -EPERM;
nvmet_loop_port = port;
return 0;
}
static void nvme_loop_remove_port(struct nvmet_port *port)
{
if (port == nvmet_loop_port)
nvmet_loop_port = NULL;
}
static struct nvmet_fabrics_ops nvme_loop_ops = {
.owner = THIS_MODULE,
.type = NVMF_TRTYPE_LOOP,
.add_port = nvme_loop_add_port,
.remove_port = nvme_loop_remove_port,
.queue_response = nvme_loop_queue_response,
.delete_ctrl = nvme_loop_delete_ctrl,
};
static struct nvmf_transport_ops nvme_loop_transport = {
.name = "loop",
.create_ctrl = nvme_loop_create_ctrl,
};
static int __init nvme_loop_init_module(void)
{
int ret;
ret = nvmet_register_transport(&nvme_loop_ops);
if (ret)
return ret;
nvmf_register_transport(&nvme_loop_transport);
return 0;
}
static void __exit nvme_loop_cleanup_module(void)
{
struct nvme_loop_ctrl *ctrl, *next;
nvmf_unregister_transport(&nvme_loop_transport);
nvmet_unregister_transport(&nvme_loop_ops);
mutex_lock(&nvme_loop_ctrl_mutex);
list_for_each_entry_safe(ctrl, next, &nvme_loop_ctrl_list, list)
__nvme_loop_del_ctrl(ctrl);
mutex_unlock(&nvme_loop_ctrl_mutex);
flush_scheduled_work();
}
module_init(nvme_loop_init_module);
module_exit(nvme_loop_cleanup_module);
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("nvmet-transport-254"); /* 254 == NVMF_TRTYPE_LOOP */
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