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git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - net/tipc/dbg.c
2 * net/tipc/dbg.c: TIPC print buffer routines for debuggign
4 * Copyright (c) 2003-2005, Ericsson Research Canada
5 * Copyright (c) 2005, Wind River Systems
6 * Copyright (c) 2005-2006, Ericsson AB
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the names of the copyright holders nor the names of its
18 * contributors may be used to endorse or promote products derived from
19 * this software without specific prior written permission.
21 * Alternatively, this software may be distributed under the terms of the
22 * GNU General Public License ("GPL") version 2 as published by the Free
23 * Software Foundation.
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
26 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
42 #define MAX_STRING 512
44 static char print_string
[MAX_STRING
];
45 static spinlock_t print_lock
= SPIN_LOCK_UNLOCKED
;
47 static struct print_buf cons_buf
= { NULL
, 0, NULL
, NULL
};
48 struct print_buf
*CONS
= &cons_buf
;
50 static struct print_buf log_buf
= { NULL
, 0, NULL
, NULL
};
51 struct print_buf
*LOG
= &log_buf
;
54 #define FORMAT(PTR,LEN,FMT) \
58 LEN = vsprintf(PTR, FMT, args);\
64 * Locking policy when using print buffers.
66 * 1) Routines of the form printbuf_XXX() rely on the caller to prevent
67 * simultaneous use of the print buffer(s) being manipulated.
68 * 2) tipc_printf() uses 'print_lock' to prevent simultaneous use of
69 * 'print_string' and to protect its print buffer(s).
70 * 3) TEE() uses 'print_lock' to protect its print buffer(s).
71 * 4) Routines of the form log_XXX() uses 'print_lock' to protect LOG.
75 * printbuf_init - initialize print buffer to empty
78 void printbuf_init(struct print_buf
*pb
, char *raw
, u32 sz
)
80 if (!pb
|| !raw
|| (sz
< (MAX_STRING
+ 1)))
83 pb
->crs
= pb
->buf
= raw
;
91 * printbuf_reset - reinitialize print buffer to empty state
94 void printbuf_reset(struct print_buf
*pb
)
97 printbuf_init(pb
, pb
->buf
, pb
->size
);
101 * printbuf_empty - test if print buffer is in empty state
104 int printbuf_empty(struct print_buf
*pb
)
106 return (!pb
|| !pb
->buf
|| (pb
->crs
== pb
->buf
));
110 * printbuf_validate - check for print buffer overflow
112 * Verifies that a print buffer has captured all data written to it.
113 * If data has been lost, linearize buffer and prepend an error message
115 * Returns length of print buffer data string (including trailing NULL)
118 int printbuf_validate(struct print_buf
*pb
)
120 char *err
= " *** PRINT BUFFER WRAPPED AROUND ***\n";
127 if (pb
->buf
[pb
->size
- 1] == '\0') {
128 cp_buf
= kmalloc(pb
->size
, GFP_ATOMIC
);
130 printbuf_init(&cb
, cp_buf
, pb
->size
);
131 printbuf_move(&cb
, pb
);
132 printbuf_move(pb
, &cb
);
134 memcpy(pb
->buf
, err
, strlen(err
));
137 tipc_printf(pb
, err
);
140 return (pb
->crs
- pb
->buf
+ 1);
144 * printbuf_move - move print buffer contents to another print buffer
146 * Current contents of destination print buffer (if any) are discarded.
147 * Source print buffer becomes empty if a successful move occurs.
150 void printbuf_move(struct print_buf
*pb_to
, struct print_buf
*pb_from
)
154 /* Handle the cases where contents can't be moved */
156 if (!pb_to
|| !pb_to
->buf
)
159 if (!pb_from
|| !pb_from
->buf
) {
160 printbuf_reset(pb_to
);
164 if (pb_to
->size
< pb_from
->size
) {
165 printbuf_reset(pb_to
);
166 tipc_printf(pb_to
, "*** PRINT BUFFER OVERFLOW ***");
170 /* Copy data from char after cursor to end (if used) */
171 len
= pb_from
->buf
+ pb_from
->size
- pb_from
->crs
- 2;
172 if ((pb_from
->buf
[pb_from
->size
-1] == 0) && (len
> 0)) {
173 strcpy(pb_to
->buf
, pb_from
->crs
+ 1);
174 pb_to
->crs
= pb_to
->buf
+ len
;
176 pb_to
->crs
= pb_to
->buf
;
178 /* Copy data from start to cursor (always) */
179 len
= pb_from
->crs
- pb_from
->buf
;
180 strcpy(pb_to
->crs
, pb_from
->buf
);
183 printbuf_reset(pb_from
);
187 * tipc_printf - append formatted output to print buffer chain
190 void tipc_printf(struct print_buf
*pb
, const char *fmt
, ...)
195 struct print_buf
*pb_next
;
197 spin_lock_bh(&print_lock
);
198 FORMAT(print_string
, chars_to_add
, fmt
);
199 if (chars_to_add
>= MAX_STRING
)
200 strcpy(print_string
, "*** STRING TOO LONG ***");
204 printk(print_string
);
206 chars_left
= pb
->buf
+ pb
->size
- pb
->crs
- 1;
207 if (chars_to_add
<= chars_left
) {
208 strcpy(pb
->crs
, print_string
);
209 pb
->crs
+= chars_to_add
;
211 strcpy(pb
->buf
, print_string
+ chars_left
);
212 save_char
= print_string
[chars_left
];
213 print_string
[chars_left
] = 0;
214 strcpy(pb
->crs
, print_string
);
215 print_string
[chars_left
] = save_char
;
216 pb
->crs
= pb
->buf
+ chars_to_add
- chars_left
;
223 spin_unlock_bh(&print_lock
);
227 * TEE - perform next output operation on both print buffers
230 struct print_buf
*TEE(struct print_buf
*b0
, struct print_buf
*b1
)
232 struct print_buf
*pb
= b0
;
234 if (!b0
|| (b0
== b1
))
239 spin_lock_bh(&print_lock
);
241 if ((pb
->next
== b1
) || (pb
->next
== b0
))
242 pb
->next
= pb
->next
->next
;
247 spin_unlock_bh(&print_lock
);
252 * print_to_console - write string of bytes to console in multiple chunks
255 static void print_to_console(char *crs
, int len
)
260 int sz
= rest
< MAX_STRING
? rest
: MAX_STRING
;
264 printk((const char *)crs
);
272 * printbuf_dump - write print buffer contents to console
275 static void printbuf_dump(struct print_buf
*pb
)
279 /* Dump print buffer from char after cursor to end (if used) */
280 len
= pb
->buf
+ pb
->size
- pb
->crs
- 2;
281 if ((pb
->buf
[pb
->size
- 1] == 0) && (len
> 0))
282 print_to_console(pb
->crs
+ 1, len
);
284 /* Dump print buffer from start to cursor (always) */
285 len
= pb
->crs
- pb
->buf
;
286 print_to_console(pb
->buf
, len
);
290 * tipc_dump - dump non-console print buffer(s) to console
293 void tipc_dump(struct print_buf
*pb
, const char *fmt
, ...)
297 spin_lock_bh(&print_lock
);
298 FORMAT(CONS
->buf
, len
, fmt
);
301 for (; pb
; pb
= pb
->next
) {
304 printk("\n---- Start of dump,%s log ----\n\n",
305 (pb
== LOG
) ? "global" : "local");
308 printk("\n-------- End of dump --------\n");
310 spin_unlock_bh(&print_lock
);
314 * log_stop - free up TIPC log print buffer
319 spin_lock_bh(&print_lock
);
324 spin_unlock_bh(&print_lock
);
328 * log_reinit - set TIPC log print buffer to specified size
331 void log_reinit(int log_size
)
336 if (log_size
<= MAX_STRING
)
337 log_size
= MAX_STRING
+ 1;
338 spin_lock_bh(&print_lock
);
339 printbuf_init(LOG
, kmalloc(log_size
, GFP_ATOMIC
), log_size
);
340 spin_unlock_bh(&print_lock
);
345 * log_resize - reconfigure size of TIPC log buffer
348 struct sk_buff
*log_resize(const void *req_tlv_area
, int req_tlv_space
)
352 if (!TLV_CHECK(req_tlv_area
, req_tlv_space
, TIPC_TLV_UNSIGNED
))
353 return cfg_reply_error_string(TIPC_CFG_TLV_ERROR
);
355 value
= *(u32
*)TLV_DATA(req_tlv_area
);
356 value
= ntohl(value
);
357 if (value
!= delimit(value
, 0, 32768))
358 return cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
359 " (log size must be 0-32768)");
361 return cfg_reply_none();
365 * log_dump - capture TIPC log buffer contents in configuration message
368 struct sk_buff
*log_dump(void)
370 struct sk_buff
*reply
;
372 spin_lock_bh(&print_lock
);
374 reply
= cfg_reply_ultra_string("log not activated\n");
375 else if (printbuf_empty(LOG
))
376 reply
= cfg_reply_ultra_string("log is empty\n");
378 struct tlv_desc
*rep_tlv
;
382 str_len
= min(LOG
->size
, 32768u);
383 reply
= cfg_reply_alloc(TLV_SPACE(str_len
));
385 rep_tlv
= (struct tlv_desc
*)reply
->data
;
386 printbuf_init(&pb
, TLV_DATA(rep_tlv
), str_len
);
387 printbuf_move(&pb
, LOG
);
388 str_len
= strlen(TLV_DATA(rep_tlv
)) + 1;
389 skb_put(reply
, TLV_SPACE(str_len
));
390 TLV_SET(rep_tlv
, TIPC_TLV_ULTRA_STRING
, NULL
, str_len
);
393 spin_unlock_bh(&print_lock
);