linux_dsm_epyc7002/drivers/nvme/target/loop.c

719 lines
18 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0
/*
* NVMe over Fabrics loopback device.
* Copyright (c) 2015-2016 HGST, a Western Digital Company.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/scatterlist.h>
#include <linux/blk-mq.h>
#include <linux/nvme.h>
#include <linux/module.h>
#include <linux/parser.h>
#include "nvmet.h"
#include "../host/nvme.h"
#include "../host/fabrics.h"
#define NVME_LOOP_MAX_SEGMENTS 256
struct nvme_loop_iod {
struct nvme_request nvme_req;
struct nvme_command cmd;
struct nvme_completion cqe;
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 {
struct nvme_loop_queue *queues;
struct blk_mq_tag_set admin_tag_set;
struct list_head list;
struct blk_mq_tag_set tag_set;
struct nvme_loop_iod async_event_iod;
struct nvme_ctrl ctrl;
struct nvmet_port *port;
};
static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl)
{
return container_of(ctrl, struct nvme_loop_ctrl, ctrl);
}
enum nvme_loop_queue_flags {
NVME_LOOP_Q_LIVE = 0,
};
struct nvme_loop_queue {
struct nvmet_cq nvme_cq;
struct nvmet_sq nvme_sq;
struct nvme_loop_ctrl *ctrl;
unsigned long flags;
};
static LIST_HEAD(nvme_loop_ports);
static DEFINE_MUTEX(nvme_loop_ports_mutex);
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 const 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);
sg_free_table_chained(&iod->sg_table, NVME_INLINE_SG_CNT);
nvme_complete_rq(req);
}
static struct blk_mq_tags *nvme_loop_tagset(struct nvme_loop_queue *queue)
{
u32 queue_idx = nvme_loop_queue_idx(queue);
if (queue_idx == 0)
return queue->ctrl->admin_tag_set.tags[queue_idx];
return queue->ctrl->tag_set.tags[queue_idx - 1];
}
static void nvme_loop_queue_response(struct nvmet_req *req)
{
struct nvme_loop_queue *queue =
container_of(req->sq, struct nvme_loop_queue, nvme_sq);
struct nvme_completion *cqe = req->cqe;
/*
* 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_is_aen_req(nvme_loop_queue_idx(queue),
cqe->command_id))) {
nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status,
&cqe->result);
} else {
struct request *rq;
rq = blk_mq_tag_to_rq(nvme_loop_tagset(queue), cqe->command_id);
if (!rq) {
dev_err(queue->ctrl->ctrl.device,
"tag 0x%x on queue %d not found\n",
cqe->command_id, nvme_loop_queue_idx(queue));
return;
}
if (!nvme_try_complete_req(rq, cqe->status, cqe->result))
nvme_loop_complete_rq(rq);
}
}
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 blk_status_t 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);
bool queue_ready = test_bit(NVME_LOOP_Q_LIVE, &queue->flags);
blk_status_t ret;
if (!nvmf_check_ready(&queue->ctrl->ctrl, req, queue_ready))
return nvmf_fail_nonready_command(&queue->ctrl->ctrl, req);
ret = nvme_setup_cmd(ns, req, &iod->cmd);
if (ret)
return ret;
blk_mq_start_request(req);
iod->cmd.common.flags |= NVME_CMD_SGL_METABUF;
iod->req.port = queue->ctrl->port;
if (!nvmet_req_init(&iod->req, &queue->nvme_cq,
&queue->nvme_sq, &nvme_loop_ops))
return BLK_STS_OK;
if (blk_rq_nr_phys_segments(req)) {
iod->sg_table.sgl = iod->first_sgl;
if (sg_alloc_table_chained(&iod->sg_table,
blk_rq_nr_phys_segments(req),
iod->sg_table.sgl, NVME_INLINE_SG_CNT)) {
nvme_cleanup_cmd(req);
return BLK_STS_RESOURCE;
}
iod->req.sg = iod->sg_table.sgl;
iod->req.sg_cnt = blk_rq_map_sg(req->q, req, iod->sg_table.sgl);
iod->req.transfer_len = blk_rq_payload_bytes(req);
}
schedule_work(&iod->work);
return BLK_STS_OK;
}
static void nvme_loop_submit_async_event(struct nvme_ctrl *arg)
{
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_AQ_BLK_MQ_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)
{
iod->req.cmd = &iod->cmd;
iod->req.cqe = &iod->cqe;
iod->queue = &ctrl->queues[queue_idx];
INIT_WORK(&iod->work, nvme_loop_execute_work);
return 0;
}
static int nvme_loop_init_request(struct blk_mq_tag_set *set,
struct request *req, unsigned int hctx_idx,
unsigned int numa_node)
{
struct nvme_loop_ctrl *ctrl = set->driver_data;
nvme_req(req)->ctrl = &ctrl->ctrl;
return nvme_loop_init_iod(ctrl, blk_mq_rq_to_pdu(req),
(set == &ctrl->tag_set) ? hctx_idx + 1 : 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->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 const struct blk_mq_ops nvme_loop_mq_ops = {
.queue_rq = nvme_loop_queue_rq,
.complete = nvme_loop_complete_rq,
.init_request = nvme_loop_init_request,
.init_hctx = nvme_loop_init_hctx,
};
static const struct blk_mq_ops nvme_loop_admin_mq_ops = {
.queue_rq = nvme_loop_queue_rq,
.complete = nvme_loop_complete_rq,
.init_request = nvme_loop_init_request,
.init_hctx = nvme_loop_init_admin_hctx,
};
static void nvme_loop_destroy_admin_queue(struct nvme_loop_ctrl *ctrl)
{
clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags);
nvmet_sq_destroy(&ctrl->queues[0].nvme_sq);
blk_cleanup_queue(ctrl->ctrl.admin_q);
blk_cleanup_queue(ctrl->ctrl.fabrics_q);
blk_mq_free_tag_set(&ctrl->admin_tag_set);
}
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 void nvme_loop_destroy_io_queues(struct nvme_loop_ctrl *ctrl)
{
int i;
for (i = 1; i < ctrl->ctrl.queue_count; i++) {
clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags);
nvmet_sq_destroy(&ctrl->queues[i].nvme_sq);
}
}
static int nvme_loop_init_io_queues(struct nvme_loop_ctrl *ctrl)
{
struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
unsigned int nr_io_queues;
int ret, i;
nr_io_queues = min(opts->nr_io_queues, num_online_cpus());
ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
if (ret || !nr_io_queues)
return ret;
dev_info(ctrl->ctrl.device, "creating %d I/O queues.\n", nr_io_queues);
for (i = 1; i <= 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->ctrl.queue_count++;
}
return 0;
out_destroy_queues:
nvme_loop_destroy_io_queues(ctrl);
return ret;
}
static int nvme_loop_connect_io_queues(struct nvme_loop_ctrl *ctrl)
{
int i, ret;
for (i = 1; i < ctrl->ctrl.queue_count; i++) {
ret = nvmf_connect_io_queue(&ctrl->ctrl, i, false);
if (ret)
return ret;
set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags);
}
return 0;
}
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_AQ_MQ_TAG_DEPTH;
ctrl->admin_tag_set.reserved_tags = 2; /* connect + keep-alive */
ctrl->admin_tag_set.numa_node = ctrl->ctrl.numa_node;
ctrl->admin_tag_set.cmd_size = sizeof(struct nvme_loop_iod) +
NVME_INLINE_SG_CNT * 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->admin_tag_set.flags = BLK_MQ_F_NO_SCHED;
ctrl->queues[0].ctrl = ctrl;
error = nvmet_sq_init(&ctrl->queues[0].nvme_sq);
if (error)
return error;
ctrl->ctrl.queue_count = 1;
error = blk_mq_alloc_tag_set(&ctrl->admin_tag_set);
if (error)
goto out_free_sq;
ctrl->ctrl.admin_tagset = &ctrl->admin_tag_set;
ctrl->ctrl.fabrics_q = blk_mq_init_queue(&ctrl->admin_tag_set);
if (IS_ERR(ctrl->ctrl.fabrics_q)) {
error = PTR_ERR(ctrl->ctrl.fabrics_q);
goto out_free_tagset;
}
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_cleanup_fabrics_q;
}
error = nvmf_connect_admin_queue(&ctrl->ctrl);
if (error)
goto out_cleanup_queue;
set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags);
error = nvme_enable_ctrl(&ctrl->ctrl);
if (error)
goto out_cleanup_queue;
ctrl->ctrl.max_hw_sectors =
(NVME_LOOP_MAX_SEGMENTS - 1) << (PAGE_SHIFT - 9);
blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
error = nvme_init_identify(&ctrl->ctrl);
if (error)
goto out_cleanup_queue;
return 0;
out_cleanup_queue:
blk_cleanup_queue(ctrl->ctrl.admin_q);
out_cleanup_fabrics_q:
blk_cleanup_queue(ctrl->ctrl.fabrics_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)
{
if (ctrl->ctrl.queue_count > 1) {
nvme_stop_queues(&ctrl->ctrl);
blk_mq_tagset_busy_iter(&ctrl->tag_set,
nvme_cancel_request, &ctrl->ctrl);
blk_mq_tagset_wait_completed_request(&ctrl->tag_set);
nvme_loop_destroy_io_queues(ctrl);
}
blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
if (ctrl->ctrl.state == NVME_CTRL_LIVE)
nvme_shutdown_ctrl(&ctrl->ctrl);
blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
nvme_cancel_request, &ctrl->ctrl);
blk_mq_tagset_wait_completed_request(&ctrl->admin_tag_set);
nvme_loop_destroy_admin_queue(ctrl);
}
static void nvme_loop_delete_ctrl_host(struct nvme_ctrl *ctrl)
{
nvme_loop_shutdown_ctrl(to_loop_ctrl(ctrl));
}
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_delete_ctrl(&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, ctrl.reset_work);
int ret;
nvme_stop_ctrl(&ctrl->ctrl);
nvme_loop_shutdown_ctrl(ctrl);
if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
/* state change failure should never happen */
WARN_ON_ONCE(1);
return;
}
ret = nvme_loop_configure_admin_queue(ctrl);
if (ret)
goto out_disable;
ret = nvme_loop_init_io_queues(ctrl);
if (ret)
goto out_destroy_admin;
ret = nvme_loop_connect_io_queues(ctrl);
if (ret)
goto out_destroy_io;
blk_mq_update_nr_hw_queues(&ctrl->tag_set,
ctrl->ctrl.queue_count - 1);
if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE))
WARN_ON_ONCE(1);
nvme_start_ctrl(&ctrl->ctrl);
return;
out_destroy_io:
nvme_loop_destroy_io_queues(ctrl);
out_destroy_admin:
nvme_loop_destroy_admin_queue(ctrl);
out_disable:
dev_warn(ctrl->ctrl.device, "Removing after reset failure\n");
nvme_uninit_ctrl(&ctrl->ctrl);
}
static const struct nvme_ctrl_ops nvme_loop_ctrl_ops = {
.name = "loop",
.module = THIS_MODULE,
.flags = NVME_F_FABRICS,
.reg_read32 = nvmf_reg_read32,
.reg_read64 = nvmf_reg_read64,
.reg_write32 = nvmf_reg_write32,
.free_ctrl = nvme_loop_free_ctrl,
.submit_async_event = nvme_loop_submit_async_event,
.delete_ctrl = nvme_loop_delete_ctrl_host,
.get_address = nvmf_get_address,
};
static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl)
{
int ret;
ret = nvme_loop_init_io_queues(ctrl);
if (ret)
return ret;
memset(&ctrl->tag_set, 0, sizeof(ctrl->tag_set));
ctrl->tag_set.ops = &nvme_loop_mq_ops;
ctrl->tag_set.queue_depth = ctrl->ctrl.opts->queue_size;
ctrl->tag_set.reserved_tags = 1; /* fabric connect */
ctrl->tag_set.numa_node = ctrl->ctrl.numa_node;
ctrl->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
ctrl->tag_set.cmd_size = sizeof(struct nvme_loop_iod) +
NVME_INLINE_SG_CNT * sizeof(struct scatterlist);
ctrl->tag_set.driver_data = ctrl;
ctrl->tag_set.nr_hw_queues = ctrl->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;
}
ret = nvme_loop_connect_io_queues(ctrl);
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:
nvme_loop_destroy_io_queues(ctrl);
return ret;
}
static struct nvmet_port *nvme_loop_find_port(struct nvme_ctrl *ctrl)
{
struct nvmet_port *p, *found = NULL;
mutex_lock(&nvme_loop_ports_mutex);
list_for_each_entry(p, &nvme_loop_ports, entry) {
/* if no transport address is specified use the first port */
if ((ctrl->opts->mask & NVMF_OPT_TRADDR) &&
strcmp(ctrl->opts->traddr, p->disc_addr.traddr))
continue;
found = p;
break;
}
mutex_unlock(&nvme_loop_ports_mutex);
return found;
}
static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
struct nvmf_ctrl_options *opts)
{
struct nvme_loop_ctrl *ctrl;
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->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;
if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
WARN_ON_ONCE(1);
ret = -ENOMEM;
ctrl->ctrl.sqsize = opts->queue_size - 1;
ctrl->ctrl.kato = opts->kato;
ctrl->port = nvme_loop_find_port(&ctrl->ctrl);
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);
if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE))
WARN_ON_ONCE(1);
mutex_lock(&nvme_loop_ctrl_mutex);
list_add_tail(&ctrl->list, &nvme_loop_ctrl_list);
mutex_unlock(&nvme_loop_ctrl_mutex);
nvme_start_ctrl(&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);
nvme_put_ctrl(&ctrl->ctrl);
out:
if (ret > 0)
ret = -EIO;
return ERR_PTR(ret);
}
static int nvme_loop_add_port(struct nvmet_port *port)
{
mutex_lock(&nvme_loop_ports_mutex);
list_add_tail(&port->entry, &nvme_loop_ports);
mutex_unlock(&nvme_loop_ports_mutex);
return 0;
}
static void nvme_loop_remove_port(struct nvmet_port *port)
{
mutex_lock(&nvme_loop_ports_mutex);
list_del_init(&port->entry);
mutex_unlock(&nvme_loop_ports_mutex);
/*
* Ensure any ctrls that are in the process of being
* deleted are in fact deleted before we return
* and free the port. This is to prevent active
* ctrls from using a port after it's freed.
*/
flush_workqueue(nvme_delete_wq);
}
static const 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",
.module = THIS_MODULE,
.create_ctrl = nvme_loop_create_ctrl,
.allowed_opts = NVMF_OPT_TRADDR,
};
static int __init nvme_loop_init_module(void)
{
int ret;
ret = nvmet_register_transport(&nvme_loop_ops);
if (ret)
return ret;
ret = nvmf_register_transport(&nvme_loop_transport);
if (ret)
nvmet_unregister_transport(&nvme_loop_ops);
return ret;
}
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_delete_ctrl(&ctrl->ctrl);
mutex_unlock(&nvme_loop_ctrl_mutex);
nvme: host delete_work and reset_work on separate workqueues We need to ensure that delete_work will be hosted on a different workqueue than all the works we flush or cancel from it. Otherwise we may hit a circular dependency warning [1]. Also, given that delete_work flushes reset_work, host reset_work on nvme_reset_wq and delete_work on nvme_delete_wq. In addition, fix the flushing in the individual drivers to flush nvme_delete_wq when draining queued deletes. [1]: [ 178.491942] ============================================= [ 178.492718] [ INFO: possible recursive locking detected ] [ 178.493495] 4.9.0-rc4-c844263313a8-lb #3 Tainted: G OE [ 178.494382] --------------------------------------------- [ 178.495160] kworker/5:1/135 is trying to acquire lock: [ 178.495894] ( [ 178.496120] "nvme-wq" [ 178.496471] ){++++.+} [ 178.496599] , at: [ 178.496921] [<ffffffffa70ac206>] flush_work+0x1a6/0x2d0 [ 178.497670] but task is already holding lock: [ 178.498499] ( [ 178.498724] "nvme-wq" [ 178.499074] ){++++.+} [ 178.499202] , at: [ 178.499520] [<ffffffffa70ad6c2>] process_one_work+0x162/0x6a0 [ 178.500343] other info that might help us debug this: [ 178.501269] Possible unsafe locking scenario: [ 178.502113] CPU0 [ 178.502472] ---- [ 178.502829] lock( [ 178.503115] "nvme-wq" [ 178.503467] ); [ 178.503716] lock( [ 178.504001] "nvme-wq" [ 178.504353] ); [ 178.504601] *** DEADLOCK *** [ 178.505441] May be due to missing lock nesting notation [ 178.506453] 2 locks held by kworker/5:1/135: [ 178.507068] #0: [ 178.507330] ( [ 178.507598] "nvme-wq" [ 178.507726] ){++++.+} [ 178.508079] , at: [ 178.508173] [<ffffffffa70ad6c2>] process_one_work+0x162/0x6a0 [ 178.509004] #1: [ 178.509265] ( [ 178.509532] (&ctrl->delete_work) [ 178.509795] ){+.+.+.} [ 178.510145] , at: [ 178.510239] [<ffffffffa70ad6c2>] process_one_work+0x162/0x6a0 [ 178.511070] stack backtrace: : [ 178.511693] CPU: 5 PID: 135 Comm: kworker/5:1 Tainted: G OE 4.9.0-rc4-c844263313a8-lb #3 [ 178.512974] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014 [ 178.514247] Workqueue: nvme-wq nvme_del_ctrl_work [nvme_tcp] [ 178.515071] ffffc2668175bae0 ffffffffa7450823 ffffffffa88abd80 ffffffffa88abd80 [ 178.516195] ffffc2668175bb98 ffffffffa70eb012 ffffffffa8d8d90d ffff9c472e9ea700 [ 178.517318] ffff9c472e9ea700 ffff9c4700000000 ffff9c4700007200 ab83be61bec0d50e [ 178.518443] Call Trace: [ 178.518807] [<ffffffffa7450823>] dump_stack+0x85/0xc2 [ 178.519542] [<ffffffffa70eb012>] __lock_acquire+0x17d2/0x18f0 [ 178.520377] [<ffffffffa75839a7>] ? serial8250_console_putchar+0x27/0x30 [ 178.521330] [<ffffffffa7583980>] ? wait_for_xmitr+0xa0/0xa0 [ 178.522174] [<ffffffffa70ac1eb>] ? flush_work+0x18b/0x2d0 [ 178.522975] [<ffffffffa70eb7cb>] lock_acquire+0x11b/0x220 [ 178.523753] [<ffffffffa70ac206>] ? flush_work+0x1a6/0x2d0 [ 178.524535] [<ffffffffa70ac229>] flush_work+0x1c9/0x2d0 [ 178.525291] [<ffffffffa70ac206>] ? flush_work+0x1a6/0x2d0 [ 178.526077] [<ffffffffa70a9cf0>] ? flush_workqueue_prep_pwqs+0x220/0x220 [ 178.527040] [<ffffffffa70ae7cf>] __cancel_work_timer+0x10f/0x1d0 [ 178.527907] [<ffffffffa70fecb9>] ? vprintk_default+0x29/0x40 [ 178.528726] [<ffffffffa71cb507>] ? printk+0x48/0x50 [ 178.529434] [<ffffffffa70ae8c3>] cancel_delayed_work_sync+0x13/0x20 [ 178.530381] [<ffffffffc042100b>] nvme_stop_ctrl+0x5b/0x70 [nvme_core] [ 178.531314] [<ffffffffc0403dcc>] nvme_del_ctrl_work+0x2c/0x50 [nvme_tcp] [ 178.532271] [<ffffffffa70ad741>] process_one_work+0x1e1/0x6a0 [ 178.533101] [<ffffffffa70ad6c2>] ? process_one_work+0x162/0x6a0 [ 178.533954] [<ffffffffa70adc4e>] worker_thread+0x4e/0x490 [ 178.534735] [<ffffffffa70adc00>] ? process_one_work+0x6a0/0x6a0 [ 178.535588] [<ffffffffa70adc00>] ? process_one_work+0x6a0/0x6a0 [ 178.536441] [<ffffffffa70b48cf>] kthread+0xff/0x120 [ 178.537149] [<ffffffffa70b47d0>] ? kthread_park+0x60/0x60 [ 178.538094] [<ffffffffa70b47d0>] ? kthread_park+0x60/0x60 [ 178.538900] [<ffffffffa78e332a>] ret_from_fork+0x2a/0x40 Signed-off-by: Roy Shterman <roys@lightbitslabs.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-14 17:39:02 +07:00
flush_workqueue(nvme_delete_wq);
}
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 */