teach logfc() to handle prefices, give it saner calling conventions

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2019-12-20 22:10:36 -05:00
parent fbc2d1686d
commit 9f09f649ca
2 changed files with 27 additions and 52 deletions

View File

@ -388,64 +388,33 @@ EXPORT_SYMBOL(vfs_dup_fs_context);
* @fc: The filesystem context to log to.
* @fmt: The format of the buffer.
*/
void logfc(struct fs_context *fc, const char *fmt, ...)
void logfc(struct fc_log *log, const char *prefix, char level, const char *fmt, ...)
{
static const char store_failure[] = "OOM: Can't store error string";
struct fc_log *log = fc ? fc->log : NULL;
const char *p;
va_list va;
char *q;
u8 freeable;
struct va_format vaf = {.fmt = fmt, .va = &va};
va_start(va, fmt);
if (!strchr(fmt, '%')) {
p = fmt;
goto unformatted_string;
}
if (strcmp(fmt, "%s") == 0) {
p = va_arg(va, const char *);
goto unformatted_string;
}
q = kvasprintf(GFP_KERNEL, fmt, va);
copied_string:
if (!q)
goto store_failure;
freeable = 1;
goto store_string;
unformatted_string:
if ((unsigned long)p >= (unsigned long)__start_rodata &&
(unsigned long)p < (unsigned long)__end_rodata)
goto const_string;
if (log && within_module_core((unsigned long)p, log->owner))
goto const_string;
q = kstrdup(p, GFP_KERNEL);
goto copied_string;
store_failure:
p = store_failure;
const_string:
q = (char *)p;
freeable = 0;
store_string:
if (!log) {
switch (fmt[0]) {
switch (level) {
case 'w':
printk(KERN_WARNING "%s\n", q + 2);
printk(KERN_WARNING "%s%s%pV\n", prefix ? prefix : "",
prefix ? ": " : "", &vaf);
break;
case 'e':
printk(KERN_ERR "%s\n", q + 2);
printk(KERN_ERR "%s%s%pV\n", prefix ? prefix : "",
prefix ? ": " : "", &vaf);
break;
default:
printk(KERN_NOTICE "%s\n", q + 2);
printk(KERN_NOTICE "%s%s%pV\n", prefix ? prefix : "",
prefix ? ": " : "", &vaf);
break;
}
if (freeable)
kfree(q);
} else {
unsigned int logsize = ARRAY_SIZE(log->buffer);
u8 index;
char *q = kasprintf(GFP_KERNEL, "%c %s%s%pV\n", level,
prefix ? prefix : "",
prefix ? ": " : "", &vaf);
index = log->head & (logsize - 1);
BUILD_BUG_ON(sizeof(log->head) != sizeof(u8) ||
@ -457,9 +426,11 @@ void logfc(struct fs_context *fc, const char *fmt, ...)
log->tail++;
}
log->buffer[index] = q;
log->need_free &= ~(1 << index);
log->need_free |= freeable << index;
log->buffer[index] = q ? q : "OOM: Can't store error string";
if (q)
log->need_free |= 1 << index;
else
log->need_free &= ~(1 << index);
log->head++;
}
va_end(va);

View File

@ -181,9 +181,13 @@ struct fc_log {
char *buffer[8];
};
extern __attribute__((format(printf, 2, 3)))
void logfc(struct fs_context *fc, const char *fmt, ...);
extern __attribute__((format(printf, 4, 5)))
void logfc(struct fc_log *log, const char *prefix, char level, const char *fmt, ...);
#define __logfc(fc, l, fmt, ...) ({ \
struct fs_context *__fc = (fc); \
logfc(__fc ? __fc->log : NULL, NULL, \
l, fmt, ## __VA_ARGS__);})
/**
* infof - Store supplementary informational message
* @fc: The context in which to log the informational message
@ -192,7 +196,7 @@ void logfc(struct fs_context *fc, const char *fmt, ...);
* Store the supplementary informational message for the process if the process
* has enabled the facility.
*/
#define infof(fc, fmt, ...) ({ logfc(fc, "i "fmt, ## __VA_ARGS__); })
#define infof(fc, fmt, ...) __logfc(fc, 'i', fmt, ## __VA_ARGS__)
/**
* warnf - Store supplementary warning message
@ -202,7 +206,7 @@ void logfc(struct fs_context *fc, const char *fmt, ...);
* Store the supplementary warning message for the process if the process has
* enabled the facility.
*/
#define warnf(fc, fmt, ...) ({ logfc(fc, "w "fmt, ## __VA_ARGS__); })
#define warnf(fc, fmt, ...) __logfc(fc, 'w', fmt, ## __VA_ARGS__)
/**
* errorf - Store supplementary error message
@ -212,7 +216,7 @@ void logfc(struct fs_context *fc, const char *fmt, ...);
* Store the supplementary error message for the process if the process has
* enabled the facility.
*/
#define errorf(fc, fmt, ...) ({ logfc(fc, "e "fmt, ## __VA_ARGS__); })
#define errorf(fc, fmt, ...) __logfc(fc, 'e', fmt, ## __VA_ARGS__)
/**
* invalf - Store supplementary invalid argument error message
@ -222,6 +226,6 @@ void logfc(struct fs_context *fc, const char *fmt, ...);
* Store the supplementary error message for the process if the process has
* enabled the facility and return -EINVAL.
*/
#define invalf(fc, fmt, ...) ({ errorf(fc, fmt, ## __VA_ARGS__); -EINVAL; })
#define invalf(fc, fmt, ...) (errorf(fc, fmt, ## __VA_ARGS__), -EINVAL)
#endif /* _LINUX_FS_CONTEXT_H */