Commit 649fd414 authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Keith Busch
Browse files

nvmet: add debugfs support 



Add a debugfs hierarchy to display the configured subsystems
and the controllers attached to the subsystems.

Suggested-by: default avatarRedouane BOUFENGHOUR <redouane.boufenghour@shadow.tech>
Signed-off-by: default avatarHannes Reinecke <hare@kernel.org>
Reviewed-by: default avatarSagi Grimberg <sagi@grimberg.me>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: default avatarDaniel Wagner <dwagner@suse.de>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
parent d1237b32

drivers/nvme/target/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -17,6 +17,15 @@ 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_DEBUGFS

        bool "NVMe Target debugfs support"

	depends on NVME_TARGET

	help

	  This enables debugfs support to display the connected controllers

	  to each subsystem



	  If unsure, say N.



config NVME_TARGET_PASSTHRU

	bool "NVMe Target Passthrough support"

	depends on NVME_TARGET

drivers/nvme/target/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ obj-$(CONFIG_NVME_TARGET_TCP) += nvmet-tcp.o 


nvmet-y		+= core.o configfs.o admin-cmd.o fabrics-cmd.o \

			discovery.o io-cmd-file.o io-cmd-bdev.o

nvmet-$(CONFIG_NVME_TARGET_DEBUGFS)	+= debugfs.o

nvmet-$(CONFIG_NVME_TARGET_PASSTHRU)	+= passthru.o

nvmet-$(CONFIG_BLK_DEV_ZONED)		+= zns.o

nvmet-$(CONFIG_NVME_TARGET_AUTH)	+= fabrics-cmd-auth.o auth.o

drivers/nvme/target/core.c

+21 −1
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include "trace.h"



#include "nvmet.h"

#include "debugfs.h"



struct kmem_cache *nvmet_bvec_cache;

struct workqueue_struct *buffered_io_wq;
@@ -1478,6 +1479,7 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, 
	mutex_lock(&subsys->lock);

	list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);

	nvmet_setup_p2p_ns_map(ctrl, req);

	nvmet_debugfs_ctrl_setup(ctrl);

	mutex_unlock(&subsys->lock);



	*ctrlp = ctrl;
@@ -1512,6 +1514,8 @@ static void nvmet_ctrl_free(struct kref *ref) 


	nvmet_destroy_auth(ctrl);



	nvmet_debugfs_ctrl_free(ctrl);



	ida_free(&cntlid_ida, ctrl->cntlid);



	nvmet_async_events_free(ctrl);
@@ -1632,8 +1636,14 @@ struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn, 
	INIT_LIST_HEAD(&subsys->ctrls);

	INIT_LIST_HEAD(&subsys->hosts);



	ret = nvmet_debugfs_subsys_setup(subsys);

	if (ret)

		goto free_subsysnqn;



	return subsys;



free_subsysnqn:

	kfree(subsys->subsysnqn);

free_fr:

	kfree(subsys->firmware_rev);

free_mn:
@@ -1650,6 +1660,8 @@ static void nvmet_subsys_free(struct kref *ref) 


	WARN_ON_ONCE(!xa_empty(&subsys->namespaces));



	nvmet_debugfs_subsys_free(subsys);



	xa_destroy(&subsys->namespaces);

	nvmet_passthru_subsys_free(subsys);
@@ -1704,11 +1716,18 @@ static int __init nvmet_init(void) 
	if (error)

		goto out_free_nvmet_work_queue;



	error = nvmet_init_configfs();

	error = nvmet_init_debugfs();

	if (error)

		goto out_exit_discovery;



	error = nvmet_init_configfs();

	if (error)

		goto out_exit_debugfs;



	return 0;



out_exit_debugfs:

	nvmet_exit_debugfs();

out_exit_discovery:

	nvmet_exit_discovery();

out_free_nvmet_work_queue:
@@ -1725,6 +1744,7 @@ static int __init nvmet_init(void) 
static void __exit nvmet_exit(void)

{

	nvmet_exit_configfs();

	nvmet_exit_debugfs();

	nvmet_exit_discovery();

	ida_destroy(&cntlid_ida);

	destroy_workqueue(nvmet_wq);

drivers/nvme/target/debugfs.c

0 → 100644
+183 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * DebugFS interface for the NVMe target.

 * Copyright (c) 2022-2024 Shadow

 * Copyright (c) 2024 SUSE LLC

 */



#include <linux/debugfs.h>

#include <linux/fs.h>

#include <linux/init.h>

#include <linux/kernel.h>



#include "nvmet.h"

#include "debugfs.h"



struct dentry *nvmet_debugfs;



#define NVMET_DEBUGFS_ATTR(field) \

	static int field##_open(struct inode *inode, struct file *file) \

	{ return single_open(file, field##_show, inode->i_private); } \

	\

	static const struct file_operations field##_fops = { \

		.open = field##_open, \

		.read = seq_read, \

		.release = single_release, \

	}



#define NVMET_DEBUGFS_RW_ATTR(field) \

	static int field##_open(struct inode *inode, struct file *file) \

	{ return single_open(file, field##_show, inode->i_private); } \

	\

	static const struct file_operations field##_fops = { \

		.open = field##_open, \

		.read = seq_read, \

		.write = field##_write, \

		.release = single_release, \

	}



static int nvmet_ctrl_hostnqn_show(struct seq_file *m, void *p)

{

	struct nvmet_ctrl *ctrl = m->private;



	seq_puts(m, ctrl->hostnqn);

	return 0;

}

NVMET_DEBUGFS_ATTR(nvmet_ctrl_hostnqn);



static int nvmet_ctrl_kato_show(struct seq_file *m, void *p)

{

	struct nvmet_ctrl *ctrl = m->private;



	seq_printf(m, "%d\n", ctrl->kato);

	return 0;

}

NVMET_DEBUGFS_ATTR(nvmet_ctrl_kato);



static int nvmet_ctrl_port_show(struct seq_file *m, void *p)

{

	struct nvmet_ctrl *ctrl = m->private;



	seq_printf(m, "%d\n", le16_to_cpu(ctrl->port->disc_addr.portid));

	return 0;

}

NVMET_DEBUGFS_ATTR(nvmet_ctrl_port);



static const char *const csts_state_names[] = {

	[NVME_CSTS_RDY]		= "ready",

	[NVME_CSTS_CFS]		= "fatal",

	[NVME_CSTS_NSSRO]	= "reset",

	[NVME_CSTS_SHST_OCCUR]	= "shutdown",

	[NVME_CSTS_SHST_CMPLT]	= "completed",

	[NVME_CSTS_PP]		= "paused",

};



static int nvmet_ctrl_state_show(struct seq_file *m, void *p)

{

	struct nvmet_ctrl *ctrl = m->private;

	bool sep = false;

	int i;



	for (i = 0; i < 7; i++) {

		int state = BIT(i);



		if (!(ctrl->csts & state))

			continue;

		if (sep)

			seq_puts(m, "|");

		sep = true;

		if (csts_state_names[state])

			seq_puts(m, csts_state_names[state]);

		else

			seq_printf(m, "%d", state);

	}

	if (sep)

		seq_printf(m, "\n");

	return 0;

}



static ssize_t nvmet_ctrl_state_write(struct file *file, const char __user *buf,

				      size_t count, loff_t *ppos)

{

	struct seq_file *m = file->private_data;

	struct nvmet_ctrl *ctrl = m->private;

	char reset[16];



	if (count >= sizeof(reset))

		return -EINVAL;

	if (copy_from_user(reset, buf, count))

		return -EFAULT;

	if (!memcmp(reset, "fatal", 5))

		nvmet_ctrl_fatal_error(ctrl);

	else

		return -EINVAL;

	return count;

}

NVMET_DEBUGFS_RW_ATTR(nvmet_ctrl_state);



int nvmet_debugfs_ctrl_setup(struct nvmet_ctrl *ctrl)

{

	char name[32];

	struct dentry *parent = ctrl->subsys->debugfs_dir;

	int ret;



	if (!parent)

		return -ENODEV;

	snprintf(name, sizeof(name), "ctrl%d", ctrl->cntlid);

	ctrl->debugfs_dir = debugfs_create_dir(name, parent);

	if (IS_ERR(ctrl->debugfs_dir)) {

		ret = PTR_ERR(ctrl->debugfs_dir);

		ctrl->debugfs_dir = NULL;

		return ret;

	}

	debugfs_create_file("port", S_IRUSR, ctrl->debugfs_dir, ctrl,

			    &nvmet_ctrl_port_fops);

	debugfs_create_file("hostnqn", S_IRUSR, ctrl->debugfs_dir, ctrl,

			    &nvmet_ctrl_hostnqn_fops);

	debugfs_create_file("kato", S_IRUSR, ctrl->debugfs_dir, ctrl,

			    &nvmet_ctrl_kato_fops);

	debugfs_create_file("state", S_IRUSR | S_IWUSR, ctrl->debugfs_dir, ctrl,

			    &nvmet_ctrl_state_fops);

	return 0;

}



void nvmet_debugfs_ctrl_free(struct nvmet_ctrl *ctrl)

{

	debugfs_remove_recursive(ctrl->debugfs_dir);

}



int nvmet_debugfs_subsys_setup(struct nvmet_subsys *subsys)

{

	int ret = 0;



	subsys->debugfs_dir = debugfs_create_dir(subsys->subsysnqn,

						 nvmet_debugfs);

	if (IS_ERR(subsys->debugfs_dir)) {

		ret = PTR_ERR(subsys->debugfs_dir);

		subsys->debugfs_dir = NULL;

	}

	return ret;

}



void nvmet_debugfs_subsys_free(struct nvmet_subsys *subsys)

{

	debugfs_remove_recursive(subsys->debugfs_dir);

}



int __init nvmet_init_debugfs(void)

{

	struct dentry *parent;



	parent = debugfs_create_dir("nvmet", NULL);

	if (IS_ERR(parent)) {

		pr_warn("%s: failed to create debugfs directory\n", "nvmet");

		return PTR_ERR(parent);

	}

	nvmet_debugfs = parent;

	return 0;

}



void nvmet_exit_debugfs(void)

{

	debugfs_remove_recursive(nvmet_debugfs);

}

drivers/nvme/target/debugfs.h

0 → 100644
+42 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/*

 * DebugFS interface for the NVMe target.

 * Copyright (c) 2022-2024 Shadow

 * Copyright (c) 2024 SUSE LLC

 */

#ifndef NVMET_DEBUGFS_H

#define NVMET_DEBUGFS_H



#include <linux/types.h>



#ifdef CONFIG_NVME_TARGET_DEBUGFS

int nvmet_debugfs_subsys_setup(struct nvmet_subsys *subsys);

void nvmet_debugfs_subsys_free(struct nvmet_subsys *subsys);

int nvmet_debugfs_ctrl_setup(struct nvmet_ctrl *ctrl);

void nvmet_debugfs_ctrl_free(struct nvmet_ctrl *ctrl);



int __init nvmet_init_debugfs(void);

void nvmet_exit_debugfs(void);

#else

static inline int nvmet_debugfs_subsys_setup(struct nvmet_subsys *subsys)

{

	return 0;

}

static inline void nvmet_debugfs_subsys_free(struct nvmet_subsys *subsys){}



static inline int nvmet_debugfs_ctrl_setup(struct nvmet_ctrl *ctrl)

{

	return 0;

}

static inline void nvmet_debugfs_ctrl_free(struct nvmet_ctrl *ctrl) {}



static inline int __init nvmet_init_debugfs(void)

{

    return 0;

}



static inline void nvmet_exit_debugfs(void) {}



#endif



#endif /* NVMET_DEBUGFS_H */