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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 15:05:40 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 15:05:40 -0700 |
commit | a5e6b135bdff649e4330f98e2e80dbb1984f7e77 (patch) | |
tree | 475bfb1163c59d1370fd77415255afba768f9520 /kernel/printk.c | |
parent | 971f115a50afbe409825c9f3399d5a3b9aca4381 (diff) | |
parent | 9d90c8d9cde929cbc575098e825d7c29d9f45054 (diff) | |
download | kernel_goldelico_gta04-a5e6b135bdff649e4330f98e2e80dbb1984f7e77.zip kernel_goldelico_gta04-a5e6b135bdff649e4330f98e2e80dbb1984f7e77.tar.gz kernel_goldelico_gta04-a5e6b135bdff649e4330f98e2e80dbb1984f7e77.tar.bz2 |
Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (50 commits)
printk: do not mangle valid userspace syslog prefixes
efivars: Add Documentation
efivars: Expose efivars functionality to external drivers.
efivars: Parameterize operations.
efivars: Split out variable registration
efivars: parameterize efivars
efivars: Make efivars bin_attributes dynamic
efivars: move efivars globals into struct efivars
drivers:misc: ti-st: fix debugging code
kref: Fix typo in kref documentation
UIO: add PRUSS UIO driver support
Fix spelling mistakes in Documentation/zh_CN/SubmittingPatches
firmware: Fix unaligned memory accesses in dmi-sysfs
firmware: Add documentation for /sys/firmware/dmi
firmware: Expose DMI type 15 System Event Log
firmware: Break out system_event_log in dmi-sysfs
firmware: Basic dmi-sysfs support
firmware: Add DMI entry types to the headers
Driver core: convert platform_{get,set}_drvdata to static inline functions
Translate linux-2.6/Documentation/magic-number.txt into Chinese
...
Diffstat (limited to 'kernel/printk.c')
-rw-r--r-- | kernel/printk.c | 138 |
1 files changed, 104 insertions, 34 deletions
diff --git a/kernel/printk.c b/kernel/printk.c index 3623152..33284ad 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -515,6 +515,71 @@ static void _call_console_drivers(unsigned start, } /* + * Parse the syslog header <[0-9]*>. The decimal value represents 32bit, the + * lower 3 bit are the log level, the rest are the log facility. In case + * userspace passes usual userspace syslog messages to /dev/kmsg or + * /dev/ttyprintk, the log prefix might contain the facility. Printk needs + * to extract the correct log level for in-kernel processing, and not mangle + * the original value. + * + * If a prefix is found, the length of the prefix is returned. If 'level' is + * passed, it will be filled in with the log level without a possible facility + * value. If 'special' is passed, the special printk prefix chars are accepted + * and returned. If no valid header is found, 0 is returned and the passed + * variables are not touched. + */ +static size_t log_prefix(const char *p, unsigned int *level, char *special) +{ + unsigned int lev = 0; + char sp = '\0'; + size_t len; + + if (p[0] != '<' || !p[1]) + return 0; + if (p[2] == '>') { + /* usual single digit level number or special char */ + switch (p[1]) { + case '0' ... '7': + lev = p[1] - '0'; + break; + case 'c': /* KERN_CONT */ + case 'd': /* KERN_DEFAULT */ + sp = p[1]; + break; + default: + return 0; + } + len = 3; + } else { + /* multi digit including the level and facility number */ + char *endp = NULL; + + if (p[1] < '0' && p[1] > '9') + return 0; + + lev = (simple_strtoul(&p[1], &endp, 10) & 7); + if (endp == NULL || endp[0] != '>') + return 0; + len = (endp + 1) - p; + } + + /* do not accept special char if not asked for */ + if (sp && !special) + return 0; + + if (special) { + *special = sp; + /* return special char, do not touch level */ + if (sp) + return len; + } + + if (level) + *level = lev; + return len; +} + +/* * Call the console drivers, asking them to write out * log_buf[start] to log_buf[end - 1]. * The console_lock must be held. @@ -529,13 +594,9 @@ static void call_console_drivers(unsigned start, unsigned end) cur_index = start; start_print = start; while (cur_index != end) { - if (msg_level < 0 && ((end - cur_index) > 2) && - LOG_BUF(cur_index + 0) == '<' && - LOG_BUF(cur_index + 1) >= '0' && - LOG_BUF(cur_index + 1) <= '7' && - LOG_BUF(cur_index + 2) == '>') { - msg_level = LOG_BUF(cur_index + 1) - '0'; - cur_index += 3; + if (msg_level < 0 && ((end - cur_index) > 2)) { + /* strip log prefix */ + cur_index += log_prefix(&LOG_BUF(cur_index), &msg_level, NULL); start_print = cur_index; } while (cur_index != end) { @@ -733,6 +794,8 @@ asmlinkage int vprintk(const char *fmt, va_list args) unsigned long flags; int this_cpu; char *p; + size_t plen; + char special; boot_delay_msec(); printk_delay(); @@ -773,45 +836,52 @@ asmlinkage int vprintk(const char *fmt, va_list args) printed_len += vscnprintf(printk_buf + printed_len, sizeof(printk_buf) - printed_len, fmt, args); - p = printk_buf; - /* Do we have a loglevel in the string? */ - if (p[0] == '<') { - unsigned char c = p[1]; - if (c && p[2] == '>') { - switch (c) { - case '0' ... '7': /* loglevel */ - current_log_level = c - '0'; - /* Fallthrough - make sure we're on a new line */ - case 'd': /* KERN_DEFAULT */ - if (!new_text_line) { - emit_log_char('\n'); - new_text_line = 1; - } - /* Fallthrough - skip the loglevel */ - case 'c': /* KERN_CONT */ - p += 3; - break; + /* Read log level and handle special printk prefix */ + plen = log_prefix(p, ¤t_log_level, &special); + if (plen) { + p += plen; + + switch (special) { + case 'c': /* Strip <c> KERN_CONT, continue line */ + plen = 0; + break; + case 'd': /* Strip <d> KERN_DEFAULT, start new line */ + plen = 0; + default: + if (!new_text_line) { + emit_log_char('\n'); + new_text_line = 1; } } } /* - * Copy the output into log_buf. If the caller didn't provide - * appropriate log level tags, we insert them here + * Copy the output into log_buf. If the caller didn't provide + * the appropriate log prefix, we insert them here */ - for ( ; *p; p++) { + for (; *p; p++) { if (new_text_line) { - /* Always output the token */ - emit_log_char('<'); - emit_log_char(current_log_level + '0'); - emit_log_char('>'); - printed_len += 3; new_text_line = 0; + if (plen) { + /* Copy original log prefix */ + int i; + + for (i = 0; i < plen; i++) + emit_log_char(printk_buf[i]); + printed_len += plen; + } else { + /* Add log prefix */ + emit_log_char('<'); + emit_log_char(current_log_level + '0'); + emit_log_char('>'); + printed_len += 3; + } + if (printk_time) { - /* Follow the token with the time */ + /* Add the current time stamp */ char tbuf[50], *tp; unsigned tlen; unsigned long long t; |