xref: /linux/drivers/nvme/target/debugfs.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * DebugFS interface for the NVMe target.
4  * Copyright (c) 2022-2024 Shadow
5  * Copyright (c) 2024 SUSE LLC
6  */
7 
8 #include <linux/debugfs.h>
9 #include <linux/fs.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 
13 #include "nvmet.h"
14 #include "debugfs.h"
15 
16 static struct dentry *nvmet_debugfs;
17 
18 #define NVMET_DEBUGFS_ATTR(field) \
19 	static int field##_open(struct inode *inode, struct file *file) \
20 	{ return single_open(file, field##_show, inode->i_private); } \
21 	\
22 	static const struct file_operations field##_fops = { \
23 		.open = field##_open, \
24 		.read = seq_read, \
25 		.release = single_release, \
26 	}
27 
28 #define NVMET_DEBUGFS_RW_ATTR(field) \
29 	static int field##_open(struct inode *inode, struct file *file) \
30 	{ return single_open(file, field##_show, inode->i_private); } \
31 	\
32 	static const struct file_operations field##_fops = { \
33 		.open = field##_open, \
34 		.read = seq_read, \
35 		.write = field##_write, \
36 		.release = single_release, \
37 	}
38 
39 static int nvmet_ctrl_hostnqn_show(struct seq_file *m, void *p)
40 {
41 	struct nvmet_ctrl *ctrl = m->private;
42 
43 	seq_puts(m, ctrl->hostnqn);
44 	return 0;
45 }
46 NVMET_DEBUGFS_ATTR(nvmet_ctrl_hostnqn);
47 
48 static int nvmet_ctrl_kato_show(struct seq_file *m, void *p)
49 {
50 	struct nvmet_ctrl *ctrl = m->private;
51 
52 	seq_printf(m, "%d\n", ctrl->kato);
53 	return 0;
54 }
55 NVMET_DEBUGFS_ATTR(nvmet_ctrl_kato);
56 
57 static int nvmet_ctrl_port_show(struct seq_file *m, void *p)
58 {
59 	struct nvmet_ctrl *ctrl = m->private;
60 
61 	seq_printf(m, "%d\n", le16_to_cpu(ctrl->port->disc_addr.portid));
62 	return 0;
63 }
64 NVMET_DEBUGFS_ATTR(nvmet_ctrl_port);
65 
66 static const char *const csts_state_names[] = {
67 	[NVME_CSTS_RDY]		= "ready",
68 	[NVME_CSTS_CFS]		= "fatal",
69 	[NVME_CSTS_NSSRO]	= "reset",
70 	[NVME_CSTS_SHST_OCCUR]	= "shutdown",
71 	[NVME_CSTS_SHST_CMPLT]	= "completed",
72 	[NVME_CSTS_PP]		= "paused",
73 };
74 
75 static int nvmet_ctrl_state_show(struct seq_file *m, void *p)
76 {
77 	struct nvmet_ctrl *ctrl = m->private;
78 	bool sep = false;
79 	int i;
80 
81 	for (i = 0; i < 7; i++) {
82 		int state = BIT(i);
83 
84 		if (!(ctrl->csts & state))
85 			continue;
86 		if (sep)
87 			seq_puts(m, "|");
88 		sep = true;
89 		if (csts_state_names[state])
90 			seq_puts(m, csts_state_names[state]);
91 		else
92 			seq_printf(m, "%d", state);
93 	}
94 	if (sep)
95 		seq_printf(m, "\n");
96 	return 0;
97 }
98 
99 static ssize_t nvmet_ctrl_state_write(struct file *file, const char __user *buf,
100 				      size_t count, loff_t *ppos)
101 {
102 	struct seq_file *m = file->private_data;
103 	struct nvmet_ctrl *ctrl = m->private;
104 	char reset[16];
105 
106 	if (count >= sizeof(reset))
107 		return -EINVAL;
108 	if (copy_from_user(reset, buf, count))
109 		return -EFAULT;
110 	if (!memcmp(reset, "fatal", 5))
111 		nvmet_ctrl_fatal_error(ctrl);
112 	else
113 		return -EINVAL;
114 	return count;
115 }
116 NVMET_DEBUGFS_RW_ATTR(nvmet_ctrl_state);
117 
118 static int nvmet_ctrl_host_traddr_show(struct seq_file *m, void *p)
119 {
120 	struct nvmet_ctrl *ctrl = m->private;
121 	ssize_t size;
122 	char buf[NVMF_TRADDR_SIZE + 1];
123 
124 	size = nvmet_ctrl_host_traddr(ctrl, buf, NVMF_TRADDR_SIZE);
125 	if (size < 0) {
126 		buf[0] = '\0';
127 		size = 0;
128 	}
129 	buf[size] = '\0';
130 	seq_printf(m, "%s\n", buf);
131 	return 0;
132 }
133 NVMET_DEBUGFS_ATTR(nvmet_ctrl_host_traddr);
134 
135 int nvmet_debugfs_ctrl_setup(struct nvmet_ctrl *ctrl)
136 {
137 	char name[32];
138 	struct dentry *parent = ctrl->subsys->debugfs_dir;
139 	int ret;
140 
141 	if (!parent)
142 		return -ENODEV;
143 	snprintf(name, sizeof(name), "ctrl%d", ctrl->cntlid);
144 	ctrl->debugfs_dir = debugfs_create_dir(name, parent);
145 	if (IS_ERR(ctrl->debugfs_dir)) {
146 		ret = PTR_ERR(ctrl->debugfs_dir);
147 		ctrl->debugfs_dir = NULL;
148 		return ret;
149 	}
150 	debugfs_create_file("port", S_IRUSR, ctrl->debugfs_dir, ctrl,
151 			    &nvmet_ctrl_port_fops);
152 	debugfs_create_file("hostnqn", S_IRUSR, ctrl->debugfs_dir, ctrl,
153 			    &nvmet_ctrl_hostnqn_fops);
154 	debugfs_create_file("kato", S_IRUSR, ctrl->debugfs_dir, ctrl,
155 			    &nvmet_ctrl_kato_fops);
156 	debugfs_create_file("state", S_IRUSR | S_IWUSR, ctrl->debugfs_dir, ctrl,
157 			    &nvmet_ctrl_state_fops);
158 	debugfs_create_file("host_traddr", S_IRUSR, ctrl->debugfs_dir, ctrl,
159 			    &nvmet_ctrl_host_traddr_fops);
160 	return 0;
161 }
162 
163 void nvmet_debugfs_ctrl_free(struct nvmet_ctrl *ctrl)
164 {
165 	debugfs_remove_recursive(ctrl->debugfs_dir);
166 }
167 
168 int nvmet_debugfs_subsys_setup(struct nvmet_subsys *subsys)
169 {
170 	int ret = 0;
171 
172 	subsys->debugfs_dir = debugfs_create_dir(subsys->subsysnqn,
173 						 nvmet_debugfs);
174 	if (IS_ERR(subsys->debugfs_dir)) {
175 		ret = PTR_ERR(subsys->debugfs_dir);
176 		subsys->debugfs_dir = NULL;
177 	}
178 	return ret;
179 }
180 
181 void nvmet_debugfs_subsys_free(struct nvmet_subsys *subsys)
182 {
183 	debugfs_remove_recursive(subsys->debugfs_dir);
184 }
185 
186 int __init nvmet_init_debugfs(void)
187 {
188 	struct dentry *parent;
189 
190 	parent = debugfs_create_dir("nvmet", NULL);
191 	if (IS_ERR(parent)) {
192 		pr_warn("%s: failed to create debugfs directory\n", "nvmet");
193 		return PTR_ERR(parent);
194 	}
195 	nvmet_debugfs = parent;
196 	return 0;
197 }
198 
199 void nvmet_exit_debugfs(void)
200 {
201 	debugfs_remove_recursive(nvmet_debugfs);
202 }
203