Bradley Grove | 26780d9 | 2013-08-23 10:35:45 -0400 | [diff] [blame] | 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 | /** |
| 105 | * the master logging function. this function will format the message as |
| 106 | * outlined by the formatting string, the input device information and the |
| 107 | * substitution arguments and output the resulting string to the system log. |
| 108 | * |
| 109 | * @param [in] level the event log level of the message |
| 110 | * @param [in] dev the device information |
| 111 | * @param [in] format the formatting string for the message |
| 112 | * @param [in] args the substition arguments to the formatting string |
| 113 | * |
| 114 | * @return 0 on success, or -1 if an error occurred. |
| 115 | */ |
| 116 | static int esas2r_log_master(const long level, |
| 117 | const struct device *dev, |
| 118 | const char *format, |
| 119 | va_list args) |
| 120 | { |
| 121 | if (level <= event_log_level) { |
| 122 | unsigned long flags = 0; |
| 123 | int retval = 0; |
| 124 | char *buffer = event_buffer; |
| 125 | size_t buflen = EVENT_LOG_BUFF_SIZE; |
| 126 | const char *fmt_nodev = "%s%s: "; |
| 127 | const char *fmt_dev = "%s%s [%s, %s, %s]"; |
| 128 | const char *slevel = |
| 129 | translate_esas2r_event_level_to_kernel(level); |
| 130 | |
| 131 | spin_lock_irqsave(&event_buffer_lock, flags); |
| 132 | |
| 133 | if (buffer == NULL) { |
| 134 | spin_unlock_irqrestore(&event_buffer_lock, flags); |
| 135 | return -1; |
| 136 | } |
| 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(buffer, buflen, fmt_nodev, slevel, |
| 148 | ESAS2R_DRVR_NAME); |
| 149 | } else { |
| 150 | snprintf(buffer, buflen, 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(buffer, buflen, format, args); |
| 161 | if (retval < 0) { |
| 162 | spin_unlock_irqrestore(&event_buffer_lock, flags); |
| 163 | return -1; |
| 164 | } |
| 165 | |
| 166 | /* |
| 167 | * Put a line break at the end of the formatted string so that |
Kees Cook | b9c2446 | 2013-12-18 10:00:54 -0800 | [diff] [blame] | 168 | * we don't wind up with run-on messages. |
Bradley Grove | 26780d9 | 2013-08-23 10:35:45 -0400 | [diff] [blame] | 169 | */ |
Kees Cook | b9c2446 | 2013-12-18 10:00:54 -0800 | [diff] [blame] | 170 | printk("%s\n", event_buffer); |
Bradley Grove | 26780d9 | 2013-08-23 10:35:45 -0400 | [diff] [blame] | 171 | |
| 172 | spin_unlock_irqrestore(&event_buffer_lock, flags); |
| 173 | } |
| 174 | |
| 175 | return 0; |
| 176 | } |
| 177 | |
| 178 | /** |
| 179 | * formats and logs a message to the system log. |
| 180 | * |
| 181 | * @param [in] level the event level of the message |
| 182 | * @param [in] format the formating string for the message |
| 183 | * @param [in] ... the substitution arguments to the formatting string |
| 184 | * |
| 185 | * @return 0 on success, or -1 if an error occurred. |
| 186 | */ |
| 187 | int esas2r_log(const long level, const char *format, ...) |
| 188 | { |
| 189 | int retval = 0; |
| 190 | va_list args; |
| 191 | |
| 192 | va_start(args, format); |
| 193 | |
| 194 | retval = esas2r_log_master(level, NULL, format, args); |
| 195 | |
| 196 | va_end(args); |
| 197 | |
| 198 | return retval; |
| 199 | } |
| 200 | |
| 201 | /** |
| 202 | * formats and logs a message to the system log. this message will include |
| 203 | * device information. |
| 204 | * |
| 205 | * @param [in] level the event level of the message |
| 206 | * @param [in] dev the device information |
| 207 | * @param [in] format the formatting string for the message |
| 208 | * @param [in] ... the substitution arguments to the formatting string |
| 209 | * |
| 210 | * @return 0 on success, or -1 if an error occurred. |
| 211 | */ |
| 212 | int esas2r_log_dev(const long level, |
| 213 | const struct device *dev, |
| 214 | const char *format, |
| 215 | ...) |
| 216 | { |
| 217 | int retval = 0; |
| 218 | va_list args; |
| 219 | |
| 220 | va_start(args, format); |
| 221 | |
| 222 | retval = esas2r_log_master(level, dev, format, args); |
| 223 | |
| 224 | va_end(args); |
| 225 | |
| 226 | return retval; |
| 227 | } |
| 228 | |
| 229 | /** |
| 230 | * formats and logs a message to the system log. this message will include |
| 231 | * device information. |
| 232 | * |
| 233 | * @param [in] level the event level of the message |
| 234 | * @param [in] buf |
| 235 | * @param [in] len |
| 236 | * |
| 237 | * @return 0 on success, or -1 if an error occurred. |
| 238 | */ |
| 239 | int esas2r_log_hexdump(const long level, |
| 240 | const void *buf, |
| 241 | size_t len) |
| 242 | { |
| 243 | if (level <= event_log_level) { |
| 244 | print_hex_dump(translate_esas2r_event_level_to_kernel(level), |
| 245 | "", DUMP_PREFIX_OFFSET, 16, 1, buf, |
| 246 | len, true); |
| 247 | } |
| 248 | |
| 249 | return 1; |
| 250 | } |