kmsg - kmsg_dump() use iterator to receive log buffer content
Provide an iterator to receive the log buffer content, and convert all
kmsg_dump() users to it.
The structured data in the kmsg buffer now contains binary data, which
should no longer be copied verbatim to the kmsg_dump() users.
The iterator should provide reliable access to the buffer data, and also
supports proper log line-aware chunking of data while iterating.
Signed-off-by: Kay Sievers <kay@vrfy.org>
Tested-by: Tony Luck <tony.luck@intel.com>
Reported-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Tested-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
index 35f7237..af4eb5a 100644
--- a/include/linux/kmsg_dump.h
+++ b/include/linux/kmsg_dump.h
@@ -21,6 +21,7 @@
* is passed to the kernel.
*/
enum kmsg_dump_reason {
+ KMSG_DUMP_UNDEF,
KMSG_DUMP_PANIC,
KMSG_DUMP_OOPS,
KMSG_DUMP_EMERG,
@@ -31,23 +32,37 @@
/**
* struct kmsg_dumper - kernel crash message dumper structure
- * @dump: The callback which gets called on crashes. The buffer is passed
- * as two sections, where s1 (length l1) contains the older
- * messages and s2 (length l2) contains the newer.
* @list: Entry in the dumper list (private)
+ * @dump: Call into dumping code which will retrieve the data with
+ * through the record iterator
+ * @max_reason: filter for highest reason number that should be dumped
* @registered: Flag that specifies if this is already registered
*/
struct kmsg_dumper {
- void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason,
- const char *s1, unsigned long l1,
- const char *s2, unsigned long l2);
struct list_head list;
- int registered;
+ void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
+ enum kmsg_dump_reason max_reason;
+ bool active;
+ bool registered;
+
+ /* private state of the kmsg iterator */
+ u32 cur_idx;
+ u32 next_idx;
+ u64 cur_seq;
+ u64 next_seq;
};
#ifdef CONFIG_PRINTK
void kmsg_dump(enum kmsg_dump_reason reason);
+bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+ char *line, size_t size, size_t *len);
+
+bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
+ char *buf, size_t size, size_t *len);
+
+void kmsg_dump_rewind(struct kmsg_dumper *dumper);
+
int kmsg_dump_register(struct kmsg_dumper *dumper);
int kmsg_dump_unregister(struct kmsg_dumper *dumper);
@@ -56,6 +71,22 @@
{
}
+bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+ const char *line, size_t size, size_t *len)
+{
+ return false;
+}
+
+bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
+ char *buf, size_t size, size_t *len)
+{
+ return false;
+}
+
+void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+{
+}
+
static inline int kmsg_dump_register(struct kmsg_dumper *dumper)
{
return -EINVAL;