1/*
2 * scsi_logging.c
3 *
4 * Copyright (C) 2014 SUSE Linux Products GmbH
5 * Copyright (C) 2014 Hannes Reinecke <hare@suse.de>
6 *
7 * This file is released under the GPLv2
8 */
9
10#include <linux/kernel.h>
11#include <linux/atomic.h>
12
13#include <scsi/scsi.h>
14#include <scsi/scsi_cmnd.h>
15#include <scsi/scsi_device.h>
16#include <scsi/scsi_eh.h>
17#include <scsi/scsi_dbg.h>
18
19#define SCSI_LOG_SPOOLSIZE 4096
20
21#if (SCSI_LOG_SPOOLSIZE / SCSI_LOG_BUFSIZE) > BITS_PER_LONG
22#warning SCSI logging bitmask too large
23#endif
24
25struct scsi_log_buf {
26	char buffer[SCSI_LOG_SPOOLSIZE];
27	unsigned long map;
28};
29
30static DEFINE_PER_CPU(struct scsi_log_buf, scsi_format_log);
31
32static char *scsi_log_reserve_buffer(size_t *len)
33{
34	struct scsi_log_buf *buf;
35	unsigned long map_bits = sizeof(buf->buffer) / SCSI_LOG_BUFSIZE;
36	unsigned long idx = 0;
37
38	preempt_disable();
39	buf = this_cpu_ptr(&scsi_format_log);
40	idx = find_first_zero_bit(&buf->map, map_bits);
41	if (likely(idx < map_bits)) {
42		while (test_and_set_bit(idx, &buf->map)) {
43			idx = find_next_zero_bit(&buf->map, map_bits, idx);
44			if (idx >= map_bits)
45				break;
46		}
47	}
48	if (WARN_ON(idx >= map_bits)) {
49		preempt_enable();
50		return NULL;
51	}
52	*len = SCSI_LOG_BUFSIZE;
53	return buf->buffer + idx * SCSI_LOG_BUFSIZE;
54}
55
56static void scsi_log_release_buffer(char *bufptr)
57{
58	struct scsi_log_buf *buf;
59	unsigned long idx;
60	int ret;
61
62	buf = this_cpu_ptr(&scsi_format_log);
63	if (bufptr >= buf->buffer &&
64	    bufptr < buf->buffer + SCSI_LOG_SPOOLSIZE) {
65		idx = (bufptr - buf->buffer) / SCSI_LOG_BUFSIZE;
66		ret = test_and_clear_bit(idx, &buf->map);
67		WARN_ON(!ret);
68	}
69	preempt_enable();
70}
71
72static inline const char *scmd_name(const struct scsi_cmnd *scmd)
73{
74	return scmd->request->rq_disk ?
75		scmd->request->rq_disk->disk_name : NULL;
76}
77
78static size_t sdev_format_header(char *logbuf, size_t logbuf_len,
79				 const char *name, int tag)
80{
81	size_t off = 0;
82
83	if (name)
84		off += scnprintf(logbuf + off, logbuf_len - off,
85				 "[%s] ", name);
86
87	if (WARN_ON(off >= logbuf_len))
88		return off;
89
90	if (tag >= 0)
91		off += scnprintf(logbuf + off, logbuf_len - off,
92				 "tag#%d ", tag);
93	return off;
94}
95
96void sdev_prefix_printk(const char *level, const struct scsi_device *sdev,
97			const char *name, const char *fmt, ...)
98{
99	va_list args;
100	char *logbuf;
101	size_t off = 0, logbuf_len;
102
103	if (!sdev)
104		return;
105
106	logbuf = scsi_log_reserve_buffer(&logbuf_len);
107	if (!logbuf)
108		return;
109
110	if (name)
111		off += scnprintf(logbuf + off, logbuf_len - off,
112				 "[%s] ", name);
113	if (!WARN_ON(off >= logbuf_len)) {
114		va_start(args, fmt);
115		off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
116		va_end(args);
117	}
118	dev_printk(level, &sdev->sdev_gendev, "%s", logbuf);
119	scsi_log_release_buffer(logbuf);
120}
121EXPORT_SYMBOL(sdev_prefix_printk);
122
123void scmd_printk(const char *level, const struct scsi_cmnd *scmd,
124		const char *fmt, ...)
125{
126	va_list args;
127	char *logbuf;
128	size_t off = 0, logbuf_len;
129
130	if (!scmd || !scmd->cmnd)
131		return;
132
133	logbuf = scsi_log_reserve_buffer(&logbuf_len);
134	if (!logbuf)
135		return;
136	off = sdev_format_header(logbuf, logbuf_len, scmd_name(scmd),
137				 scmd->request->tag);
138	if (off < logbuf_len) {
139		va_start(args, fmt);
140		off += vscnprintf(logbuf + off, logbuf_len - off, fmt, args);
141		va_end(args);
142	}
143	dev_printk(level, &scmd->device->sdev_gendev, "%s", logbuf);
144	scsi_log_release_buffer(logbuf);
145}
146EXPORT_SYMBOL(scmd_printk);
147
148static size_t scsi_format_opcode_name(char *buffer, size_t buf_len,
149				      const unsigned char *cdbp)
150{
151	int sa, cdb0;
152	const char *cdb_name = NULL, *sa_name = NULL;
153	size_t off;
154
155	cdb0 = cdbp[0];
156	if (cdb0 == VARIABLE_LENGTH_CMD) {
157		int len = scsi_varlen_cdb_length(cdbp);
158
159		if (len < 10) {
160			off = scnprintf(buffer, buf_len,
161					"short variable length command, len=%d",
162					len);
163			return off;
164		}
165		sa = (cdbp[8] << 8) + cdbp[9];
166	} else
167		sa = cdbp[1] & 0x1f;
168
169	if (!scsi_opcode_sa_name(cdb0, sa, &cdb_name, &sa_name)) {
170		if (cdb_name)
171			off = scnprintf(buffer, buf_len, "%s", cdb_name);
172		else {
173			off = scnprintf(buffer, buf_len, "opcode=0x%x", cdb0);
174			if (WARN_ON(off >= buf_len))
175				return off;
176			if (cdb0 >= VENDOR_SPECIFIC_CDB)
177				off += scnprintf(buffer + off, buf_len - off,
178						 " (vendor)");
179			else if (cdb0 >= 0x60 && cdb0 < 0x7e)
180				off += scnprintf(buffer + off, buf_len - off,
181						 " (reserved)");
182		}
183	} else {
184		if (sa_name)
185			off = scnprintf(buffer, buf_len, "%s", sa_name);
186		else if (cdb_name)
187			off = scnprintf(buffer, buf_len, "%s, sa=0x%x",
188					cdb_name, sa);
189		else
190			off = scnprintf(buffer, buf_len,
191					"opcode=0x%x, sa=0x%x", cdb0, sa);
192	}
193	WARN_ON(off >= buf_len);
194	return off;
195}
196
197size_t __scsi_format_command(char *logbuf, size_t logbuf_len,
198			     const unsigned char *cdb, size_t cdb_len)
199{
200	int len, k;
201	size_t off;
202
203	off = scsi_format_opcode_name(logbuf, logbuf_len, cdb);
204	if (off >= logbuf_len)
205		return off;
206	len = scsi_command_size(cdb);
207	if (cdb_len < len)
208		len = cdb_len;
209	/* print out all bytes in cdb */
210	for (k = 0; k < len; ++k) {
211		if (off > logbuf_len - 3)
212			break;
213		off += scnprintf(logbuf + off, logbuf_len - off,
214				 " %02x", cdb[k]);
215	}
216	return off;
217}
218EXPORT_SYMBOL(__scsi_format_command);
219
220void scsi_print_command(struct scsi_cmnd *cmd)
221{
222	int k;
223	char *logbuf;
224	size_t off, logbuf_len;
225
226	if (!cmd->cmnd)
227		return;
228
229	logbuf = scsi_log_reserve_buffer(&logbuf_len);
230	if (!logbuf)
231		return;
232
233	off = sdev_format_header(logbuf, logbuf_len,
234				 scmd_name(cmd), cmd->request->tag);
235	if (off >= logbuf_len)
236		goto out_printk;
237	off += scnprintf(logbuf + off, logbuf_len - off, "CDB: ");
238	if (WARN_ON(off >= logbuf_len))
239		goto out_printk;
240
241	off += scsi_format_opcode_name(logbuf + off, logbuf_len - off,
242				       cmd->cmnd);
243	if (off >= logbuf_len)
244		goto out_printk;
245
246	/* print out all bytes in cdb */
247	if (cmd->cmd_len > 16) {
248		/* Print opcode in one line and use separate lines for CDB */
249		off += scnprintf(logbuf + off, logbuf_len - off, "\n");
250		dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s", logbuf);
251		scsi_log_release_buffer(logbuf);
252		for (k = 0; k < cmd->cmd_len; k += 16) {
253			size_t linelen = min(cmd->cmd_len - k, 16);
254
255			logbuf = scsi_log_reserve_buffer(&logbuf_len);
256			if (!logbuf)
257				break;
258			off = sdev_format_header(logbuf, logbuf_len,
259						 scmd_name(cmd),
260						 cmd->request->tag);
261			if (!WARN_ON(off > logbuf_len - 58)) {
262				off += scnprintf(logbuf + off, logbuf_len - off,
263						 "CDB[%02x]: ", k);
264				hex_dump_to_buffer(&cmd->cmnd[k], linelen,
265						   16, 1, logbuf + off,
266						   logbuf_len - off, false);
267			}
268			dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s",
269				   logbuf);
270			scsi_log_release_buffer(logbuf);
271		}
272		return;
273	}
274	if (!WARN_ON(off > logbuf_len - 49)) {
275		off += scnprintf(logbuf + off, logbuf_len - off, " ");
276		hex_dump_to_buffer(cmd->cmnd, cmd->cmd_len, 16, 1,
277				   logbuf + off, logbuf_len - off,
278				   false);
279	}
280out_printk:
281	dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s", logbuf);
282	scsi_log_release_buffer(logbuf);
283}
284EXPORT_SYMBOL(scsi_print_command);
285
286static size_t
287scsi_format_extd_sense(char *buffer, size_t buf_len,
288		       unsigned char asc, unsigned char ascq)
289{
290	size_t off = 0;
291	const char *extd_sense_fmt = NULL;
292	const char *extd_sense_str = scsi_extd_sense_format(asc, ascq,
293							    &extd_sense_fmt);
294
295	if (extd_sense_str) {
296		off = scnprintf(buffer, buf_len, "Add. Sense: %s",
297				extd_sense_str);
298		if (extd_sense_fmt)
299			off += scnprintf(buffer + off, buf_len - off,
300					 "(%s%x)", extd_sense_fmt, ascq);
301	} else {
302		if (asc >= 0x80)
303			off = scnprintf(buffer, buf_len, "<<vendor>>");
304		off += scnprintf(buffer + off, buf_len - off,
305				 "ASC=0x%x ", asc);
306		if (ascq >= 0x80)
307			off += scnprintf(buffer + off, buf_len - off,
308					 "<<vendor>>");
309		off += scnprintf(buffer + off, buf_len - off,
310				 "ASCQ=0x%x ", ascq);
311	}
312	return off;
313}
314
315static size_t
316scsi_format_sense_hdr(char *buffer, size_t buf_len,
317		      const struct scsi_sense_hdr *sshdr)
318{
319	const char *sense_txt;
320	size_t off;
321
322	off = scnprintf(buffer, buf_len, "Sense Key : ");
323	sense_txt = scsi_sense_key_string(sshdr->sense_key);
324	if (sense_txt)
325		off += scnprintf(buffer + off, buf_len - off,
326				 "%s ", sense_txt);
327	else
328		off += scnprintf(buffer + off, buf_len - off,
329				 "0x%x ", sshdr->sense_key);
330	off += scnprintf(buffer + off, buf_len - off,
331		scsi_sense_is_deferred(sshdr) ? "[deferred] " : "[current] ");
332
333	if (sshdr->response_code >= 0x72)
334		off += scnprintf(buffer + off, buf_len - off, "[descriptor] ");
335	return off;
336}
337
338static void
339scsi_log_dump_sense(const struct scsi_device *sdev, const char *name, int tag,
340		    const unsigned char *sense_buffer, int sense_len)
341{
342	char *logbuf;
343	size_t logbuf_len;
344	int i;
345
346	logbuf = scsi_log_reserve_buffer(&logbuf_len);
347	if (!logbuf)
348		return;
349
350	for (i = 0; i < sense_len; i += 16) {
351		int len = min(sense_len - i, 16);
352		size_t off;
353
354		off = sdev_format_header(logbuf, logbuf_len,
355					 name, tag);
356		hex_dump_to_buffer(&sense_buffer[i], len, 16, 1,
357				   logbuf + off, logbuf_len - off,
358				   false);
359		dev_printk(KERN_INFO, &sdev->sdev_gendev, "%s", logbuf);
360	}
361	scsi_log_release_buffer(logbuf);
362}
363
364static void
365scsi_log_print_sense_hdr(const struct scsi_device *sdev, const char *name,
366			 int tag, const struct scsi_sense_hdr *sshdr)
367{
368	char *logbuf;
369	size_t off, logbuf_len;
370
371	logbuf = scsi_log_reserve_buffer(&logbuf_len);
372	if (!logbuf)
373		return;
374	off = sdev_format_header(logbuf, logbuf_len, name, tag);
375	off += scsi_format_sense_hdr(logbuf + off, logbuf_len - off, sshdr);
376	dev_printk(KERN_INFO, &sdev->sdev_gendev, "%s", logbuf);
377	scsi_log_release_buffer(logbuf);
378
379	logbuf = scsi_log_reserve_buffer(&logbuf_len);
380	if (!logbuf)
381		return;
382	off = sdev_format_header(logbuf, logbuf_len, name, tag);
383	off += scsi_format_extd_sense(logbuf + off, logbuf_len - off,
384				      sshdr->asc, sshdr->ascq);
385	dev_printk(KERN_INFO, &sdev->sdev_gendev, "%s", logbuf);
386	scsi_log_release_buffer(logbuf);
387}
388
389static void
390scsi_log_print_sense(const struct scsi_device *sdev, const char *name, int tag,
391		     const unsigned char *sense_buffer, int sense_len)
392{
393	struct scsi_sense_hdr sshdr;
394
395	if (scsi_normalize_sense(sense_buffer, sense_len, &sshdr))
396		scsi_log_print_sense_hdr(sdev, name, tag, &sshdr);
397	else
398		scsi_log_dump_sense(sdev, name, tag, sense_buffer, sense_len);
399}
400
401/*
402 * Print normalized SCSI sense header with a prefix.
403 */
404void
405scsi_print_sense_hdr(const struct scsi_device *sdev, const char *name,
406		     const struct scsi_sense_hdr *sshdr)
407{
408	scsi_log_print_sense_hdr(sdev, name, -1, sshdr);
409}
410EXPORT_SYMBOL(scsi_print_sense_hdr);
411
412/* Normalize and print sense buffer with name prefix */
413void __scsi_print_sense(const struct scsi_device *sdev, const char *name,
414			const unsigned char *sense_buffer, int sense_len)
415{
416	scsi_log_print_sense(sdev, name, -1, sense_buffer, sense_len);
417}
418EXPORT_SYMBOL(__scsi_print_sense);
419
420/* Normalize and print sense buffer in SCSI command */
421void scsi_print_sense(const struct scsi_cmnd *cmd)
422{
423	scsi_log_print_sense(cmd->device, scmd_name(cmd), cmd->request->tag,
424			     cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
425}
426EXPORT_SYMBOL(scsi_print_sense);
427
428void scsi_print_result(const struct scsi_cmnd *cmd, const char *msg,
429		       int disposition)
430{
431	char *logbuf;
432	size_t off, logbuf_len;
433	const char *mlret_string = scsi_mlreturn_string(disposition);
434	const char *hb_string = scsi_hostbyte_string(cmd->result);
435	const char *db_string = scsi_driverbyte_string(cmd->result);
436
437	logbuf = scsi_log_reserve_buffer(&logbuf_len);
438	if (!logbuf)
439		return;
440
441	off = sdev_format_header(logbuf, logbuf_len,
442				 scmd_name(cmd), cmd->request->tag);
443
444	if (off >= logbuf_len)
445		goto out_printk;
446
447	if (msg) {
448		off += scnprintf(logbuf + off, logbuf_len - off,
449				 "%s: ", msg);
450		if (WARN_ON(off >= logbuf_len))
451			goto out_printk;
452	}
453	if (mlret_string)
454		off += scnprintf(logbuf + off, logbuf_len - off,
455				 "%s ", mlret_string);
456	else
457		off += scnprintf(logbuf + off, logbuf_len - off,
458				 "UNKNOWN(0x%02x) ", disposition);
459	if (WARN_ON(off >= logbuf_len))
460		goto out_printk;
461
462	off += scnprintf(logbuf + off, logbuf_len - off, "Result: ");
463	if (WARN_ON(off >= logbuf_len))
464		goto out_printk;
465
466	if (hb_string)
467		off += scnprintf(logbuf + off, logbuf_len - off,
468				 "hostbyte=%s ", hb_string);
469	else
470		off += scnprintf(logbuf + off, logbuf_len - off,
471				 "hostbyte=0x%02x ", host_byte(cmd->result));
472	if (WARN_ON(off >= logbuf_len))
473		goto out_printk;
474
475	if (db_string)
476		off += scnprintf(logbuf + off, logbuf_len - off,
477				 "driverbyte=%s", db_string);
478	else
479		off += scnprintf(logbuf + off, logbuf_len - off,
480				 "driverbyte=0x%02x", driver_byte(cmd->result));
481out_printk:
482	dev_printk(KERN_INFO, &cmd->device->sdev_gendev, "%s", logbuf);
483	scsi_log_release_buffer(logbuf);
484}
485EXPORT_SYMBOL(scsi_print_result);
486