1
2
3
4
5
6
7#include "log.h"
8#include "main.h"
9
10#include <linux/compiler.h>
11#include <linux/debugfs.h>
12#include <linux/errno.h>
13#include <linux/eventpoll.h>
14#include <linux/export.h>
15#include <linux/fcntl.h>
16#include <linux/fs.h>
17#include <linux/gfp.h>
18#include <linux/jiffies.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/poll.h>
22#include <linux/sched.h>
23#include <linux/slab.h>
24#include <linux/spinlock.h>
25#include <linux/stddef.h>
26#include <linux/types.h>
27#include <linux/uaccess.h>
28#include <linux/wait.h>
29#include <stdarg.h>
30
31#include "debugfs.h"
32#include "trace.h"
33
34#ifdef CONFIG_BATMAN_ADV_DEBUGFS
35
36#define BATADV_LOG_BUFF_MASK (batadv_log_buff_len - 1)
37
38static const int batadv_log_buff_len = BATADV_LOG_BUF_LEN;
39
40static char *batadv_log_char_addr(struct batadv_priv_debug_log *debug_log,
41 size_t idx)
42{
43 return &debug_log->log_buff[idx & BATADV_LOG_BUFF_MASK];
44}
45
46static void batadv_emit_log_char(struct batadv_priv_debug_log *debug_log,
47 char c)
48{
49 char *char_addr;
50
51 char_addr = batadv_log_char_addr(debug_log, debug_log->log_end);
52 *char_addr = c;
53 debug_log->log_end++;
54
55 if (debug_log->log_end - debug_log->log_start > batadv_log_buff_len)
56 debug_log->log_start = debug_log->log_end - batadv_log_buff_len;
57}
58
59__printf(2, 3)
60static int batadv_fdebug_log(struct batadv_priv_debug_log *debug_log,
61 const char *fmt, ...)
62{
63 va_list args;
64 static char debug_log_buf[256];
65 char *p;
66
67 if (!debug_log)
68 return 0;
69
70 spin_lock_bh(&debug_log->lock);
71 va_start(args, fmt);
72 vscnprintf(debug_log_buf, sizeof(debug_log_buf), fmt, args);
73 va_end(args);
74
75 for (p = debug_log_buf; *p != 0; p++)
76 batadv_emit_log_char(debug_log, *p);
77
78 spin_unlock_bh(&debug_log->lock);
79
80 wake_up(&debug_log->queue_wait);
81
82 return 0;
83}
84
85static int batadv_log_open(struct inode *inode, struct file *file)
86{
87 if (!try_module_get(THIS_MODULE))
88 return -EBUSY;
89
90 batadv_debugfs_deprecated(file,
91 "Use tracepoint batadv:batadv_dbg instead\n");
92
93 stream_open(inode, file);
94 file->private_data = inode->i_private;
95 return 0;
96}
97
98static int batadv_log_release(struct inode *inode, struct file *file)
99{
100 module_put(THIS_MODULE);
101 return 0;
102}
103
104static bool batadv_log_empty(struct batadv_priv_debug_log *debug_log)
105{
106 return !(debug_log->log_start - debug_log->log_end);
107}
108
109static ssize_t batadv_log_read(struct file *file, char __user *buf,
110 size_t count, loff_t *ppos)
111{
112 struct batadv_priv *bat_priv = file->private_data;
113 struct batadv_priv_debug_log *debug_log = bat_priv->debug_log;
114 int error, i = 0;
115 char *char_addr;
116 char c;
117
118 if ((file->f_flags & O_NONBLOCK) && batadv_log_empty(debug_log))
119 return -EAGAIN;
120
121 if (!buf)
122 return -EINVAL;
123
124 if (count == 0)
125 return 0;
126
127 if (!access_ok(buf, count))
128 return -EFAULT;
129
130 error = wait_event_interruptible(debug_log->queue_wait,
131 (!batadv_log_empty(debug_log)));
132
133 if (error)
134 return error;
135
136 spin_lock_bh(&debug_log->lock);
137
138 while ((!error) && (i < count) &&
139 (debug_log->log_start != debug_log->log_end)) {
140 char_addr = batadv_log_char_addr(debug_log,
141 debug_log->log_start);
142 c = *char_addr;
143
144 debug_log->log_start++;
145
146 spin_unlock_bh(&debug_log->lock);
147
148 error = __put_user(c, buf);
149
150 spin_lock_bh(&debug_log->lock);
151
152 buf++;
153 i++;
154 }
155
156 spin_unlock_bh(&debug_log->lock);
157
158 if (!error)
159 return i;
160
161 return error;
162}
163
164static __poll_t batadv_log_poll(struct file *file, poll_table *wait)
165{
166 struct batadv_priv *bat_priv = file->private_data;
167 struct batadv_priv_debug_log *debug_log = bat_priv->debug_log;
168
169 poll_wait(file, &debug_log->queue_wait, wait);
170
171 if (!batadv_log_empty(debug_log))
172 return EPOLLIN | EPOLLRDNORM;
173
174 return 0;
175}
176
177static const struct file_operations batadv_log_fops = {
178 .open = batadv_log_open,
179 .release = batadv_log_release,
180 .read = batadv_log_read,
181 .poll = batadv_log_poll,
182 .llseek = no_llseek,
183 .owner = THIS_MODULE,
184};
185
186
187
188
189
190
191
192int batadv_debug_log_setup(struct batadv_priv *bat_priv)
193{
194 bat_priv->debug_log = kzalloc(sizeof(*bat_priv->debug_log), GFP_ATOMIC);
195 if (!bat_priv->debug_log)
196 return -ENOMEM;
197
198 spin_lock_init(&bat_priv->debug_log->lock);
199 init_waitqueue_head(&bat_priv->debug_log->queue_wait);
200
201 debugfs_create_file("log", 0400, bat_priv->debug_dir, bat_priv,
202 &batadv_log_fops);
203 return 0;
204}
205
206
207
208
209
210void batadv_debug_log_cleanup(struct batadv_priv *bat_priv)
211{
212 kfree(bat_priv->debug_log);
213 bat_priv->debug_log = NULL;
214}
215
216#endif
217
218
219
220
221
222
223
224
225int batadv_debug_log(struct batadv_priv *bat_priv, const char *fmt, ...)
226{
227 struct va_format vaf;
228 va_list args;
229
230 va_start(args, fmt);
231
232 vaf.fmt = fmt;
233 vaf.va = &args;
234
235#ifdef CONFIG_BATMAN_ADV_DEBUGFS
236 batadv_fdebug_log(bat_priv->debug_log, "[%10u] %pV",
237 jiffies_to_msecs(jiffies), &vaf);
238#endif
239
240 trace_batadv_dbg(bat_priv, &vaf);
241
242 va_end(args);
243
244 return 0;
245}
246