1 | /* |
2 | * linux/drivers/scsi/esas2r/esas2r_log.c |
3 | * For use with ATTO ExpressSAS R6xx SAS/SATA RAID controllers |
4 | * |
5 | * Copyright (c) 2001-2013 ATTO Technology, Inc. |
6 | * (mailto:linuxdrivers@attotech.com) |
7 | * |
8 | * This program is free software; you can redistribute it and/or |
9 | * modify it under the terms of the GNU General Public License |
10 | * as published by the Free Software Foundation; either version 2 |
11 | * of the License, or (at your option) any later version. |
12 | * |
13 | * This program is distributed in the hope that it will be useful, |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
16 | * GNU General Public License for more details. |
17 | * |
18 | * NO WARRANTY |
19 | * THE PROGRAM IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR |
20 | * CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT |
21 | * LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT, |
22 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Each Recipient is |
23 | * solely responsible for determining the appropriateness of using and |
24 | * distributing the Program and assumes all risks associated with its |
25 | * exercise of rights under this Agreement, including but not limited to |
26 | * the risks and costs of program errors, damage to or loss of data, |
27 | * programs or equipment, and unavailability or interruption of operations. |
28 | * |
29 | * DISCLAIMER OF LIABILITY |
30 | * NEITHER RECIPIENT NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY |
31 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
32 | * DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND |
33 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR |
34 | * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE |
35 | * USE OR DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED |
36 | * HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES |
37 | * |
38 | * You should have received a copy of the GNU General Public License |
39 | * along with this program; if not, write to the Free Software |
40 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, |
41 | * USA. |
42 | */ |
43 | |
44 | #include "esas2r.h" |
45 | |
46 | /* |
47 | * this module within the driver is tasked with providing logging functionality. |
48 | * the event_log_level module parameter controls the level of messages that are |
49 | * written to the system log. the default level of messages that are written |
50 | * are critical and warning messages. if other types of messages are desired, |
51 | * one simply needs to load the module with the correct value for the |
52 | * event_log_level module parameter. for example: |
53 | * |
54 | * insmod <module> event_log_level=1 |
55 | * |
56 | * will load the module and only critical events will be written by this module |
57 | * to the system log. if critical, warning, and information-level messages are |
58 | * desired, the correct value for the event_log_level module parameter |
59 | * would be as follows: |
60 | * |
61 | * insmod <module> event_log_level=3 |
62 | */ |
63 | |
64 | #define EVENT_LOG_BUFF_SIZE 1024 |
65 | |
66 | static long event_log_level = ESAS2R_LOG_DFLT; |
67 | |
68 | module_param(event_log_level, long, S_IRUGO | S_IRUSR); |
69 | MODULE_PARM_DESC(event_log_level, |
70 | "Specifies the level of events to report to the system log. Critical and warning level events are logged by default." ); |
71 | |
72 | /* A shared buffer to use for formatting messages. */ |
73 | static char event_buffer[EVENT_LOG_BUFF_SIZE]; |
74 | |
75 | /* A lock to protect the shared buffer used for formatting messages. */ |
76 | static DEFINE_SPINLOCK(event_buffer_lock); |
77 | |
78 | /* |
79 | * translates an esas2r-defined logging event level to a kernel logging level. |
80 | * |
81 | * @param [in] level the esas2r-defined logging event level to translate |
82 | * |
83 | * @return the corresponding kernel logging level. |
84 | */ |
85 | static const char *translate_esas2r_event_level_to_kernel(const long level) |
86 | { |
87 | switch (level) { |
88 | case ESAS2R_LOG_CRIT: |
89 | return KERN_CRIT; |
90 | |
91 | case ESAS2R_LOG_WARN: |
92 | return KERN_WARNING; |
93 | |
94 | case ESAS2R_LOG_INFO: |
95 | return KERN_INFO; |
96 | |
97 | case ESAS2R_LOG_DEBG: |
98 | case ESAS2R_LOG_TRCE: |
99 | default: |
100 | return KERN_DEBUG; |
101 | } |
102 | } |
103 | |
104 | #pragma GCC diagnostic push |
105 | #ifndef __clang__ |
106 | #pragma GCC diagnostic ignored "-Wsuggest-attribute=format" |
107 | #endif |
108 | |
109 | /* |
110 | * the master logging function. this function will format the message as |
111 | * outlined by the formatting string, the input device information and the |
112 | * substitution arguments and output the resulting string to the system log. |
113 | * |
114 | * @param [in] level the event log level of the message |
115 | * @param [in] dev the device information |
116 | * @param [in] format the formatting string for the message |
117 | * @param [in] args the substition arguments to the formatting string |
118 | * |
119 | * @return 0 on success, or -1 if an error occurred. |
120 | */ |
121 | static int esas2r_log_master(const long level, |
122 | const struct device *dev, |
123 | const char *format, |
124 | va_list args) |
125 | { |
126 | if (level <= event_log_level) { |
127 | unsigned long flags = 0; |
128 | int retval = 0; |
129 | char *buffer = event_buffer; |
130 | size_t buflen = EVENT_LOG_BUFF_SIZE; |
131 | const char *fmt_nodev = "%s%s: " ; |
132 | const char *fmt_dev = "%s%s [%s, %s, %s]" ; |
133 | const char *slevel = |
134 | translate_esas2r_event_level_to_kernel(level); |
135 | |
136 | spin_lock_irqsave(&event_buffer_lock, flags); |
137 | |
138 | memset(buffer, 0, buflen); |
139 | |
140 | /* |
141 | * format the level onto the beginning of the string and do |
142 | * some pointer arithmetic to move the pointer to the point |
143 | * where the actual message can be inserted. |
144 | */ |
145 | |
146 | if (dev == NULL) { |
147 | snprintf(buf: buffer, size: buflen, fmt: fmt_nodev, slevel, |
148 | ESAS2R_DRVR_NAME); |
149 | } else { |
150 | snprintf(buf: buffer, size: buflen, fmt: fmt_dev, slevel, |
151 | ESAS2R_DRVR_NAME, |
152 | (dev->driver ? dev->driver->name : "unknown" ), |
153 | (dev->bus ? dev->bus->name : "unknown" ), |
154 | dev_name(dev)); |
155 | } |
156 | |
157 | buffer += strlen(event_buffer); |
158 | buflen -= strlen(event_buffer); |
159 | |
160 | retval = vsnprintf(buf: buffer, size: buflen, fmt: format, args); |
161 | if (retval < 0) { |
162 | spin_unlock_irqrestore(lock: &event_buffer_lock, flags); |
163 | return -1; |
164 | } |
165 | |
166 | /* |
167 | * Put a line break at the end of the formatted string so that |
168 | * we don't wind up with run-on messages. |
169 | */ |
170 | printk("%s\n" , event_buffer); |
171 | |
172 | spin_unlock_irqrestore(lock: &event_buffer_lock, flags); |
173 | } |
174 | |
175 | return 0; |
176 | } |
177 | |
178 | #pragma GCC diagnostic pop |
179 | |
180 | /* |
181 | * formats and logs a message to the system log. |
182 | * |
183 | * @param [in] level the event level of the message |
184 | * @param [in] format the formating string for the message |
185 | * @param [in] ... the substitution arguments to the formatting string |
186 | * |
187 | * @return 0 on success, or -1 if an error occurred. |
188 | */ |
189 | int esas2r_log(const long level, const char *format, ...) |
190 | { |
191 | int retval = 0; |
192 | va_list args; |
193 | |
194 | va_start(args, format); |
195 | |
196 | retval = esas2r_log_master(level, NULL, format, args); |
197 | |
198 | va_end(args); |
199 | |
200 | return retval; |
201 | } |
202 | |
203 | /* |
204 | * formats and logs a message to the system log. this message will include |
205 | * device information. |
206 | * |
207 | * @param [in] level the event level of the message |
208 | * @param [in] dev the device information |
209 | * @param [in] format the formatting string for the message |
210 | * @param [in] ... the substitution arguments to the formatting string |
211 | * |
212 | * @return 0 on success, or -1 if an error occurred. |
213 | */ |
214 | int esas2r_log_dev(const long level, |
215 | const struct device *dev, |
216 | const char *format, |
217 | ...) |
218 | { |
219 | int retval = 0; |
220 | va_list args; |
221 | |
222 | va_start(args, format); |
223 | |
224 | retval = esas2r_log_master(level, dev, format, args); |
225 | |
226 | va_end(args); |
227 | |
228 | return retval; |
229 | } |
230 | |
231 | /* |
232 | * formats and logs a message to the system log. this message will include |
233 | * device information. |
234 | * |
235 | * @param [in] level the event level of the message |
236 | * @param [in] buf |
237 | * @param [in] len |
238 | * |
239 | * @return 0 on success, or -1 if an error occurred. |
240 | */ |
241 | int esas2r_log_hexdump(const long level, |
242 | const void *buf, |
243 | size_t len) |
244 | { |
245 | if (level <= event_log_level) { |
246 | print_hex_dump(level: translate_esas2r_event_level_to_kernel(level), |
247 | prefix_str: "" , prefix_type: DUMP_PREFIX_OFFSET, rowsize: 16, groupsize: 1, buf, |
248 | len, ascii: true); |
249 | } |
250 | |
251 | return 1; |
252 | } |
253 | |