1 // SPDX-License-Identifier: LGPL-2.1
15 #define COMMIT_MASK ((1 << 27) - 1)
27  * @timestamp		- timestamp of current event
28  * @lost_events		- # of lost events between this subbuffer and previous
29  * @flags		- special flags of the kbuffer
30  * @subbuffer		- pointer to the sub-buffer page
31  * @data		- pointer to the start of data on the sub-buffer page
32  * @index		- index from @data to the @curr event data
33  * @curr		- offset from @data to the start of current event
35  * @next		- offset from @data to the start of next event
36  * @size		- The size of data on @data
37  * @start		- The offset from @subbuffer where @data lives
39  * @read_4		- Function to read 4 raw bytes (may swap)
40  * @read_8		- Function to read 8 raw bytes (may swap)
41  * @read_long		- Function to read a long word (4 or 8 bytes with needed swap)
48 	void			*data;  member
52 	unsigned int		size;  member
61 static void *zmalloc(size_t size)  in zmalloc()  argument
63 	return calloc(1, size);  in zmalloc()
77 	return ((kbuf->flags & KBUFFER_FL_HOST_BIG_ENDIAN) + kbuf->flags) &  in do_swap()
83 	unsigned long long data = *(unsigned long long *)ptr;  in __read_8()  local
85 	return data;  in __read_8()
90 	unsigned long long data = *(unsigned long long *)ptr;  in __read_8_sw()  local
93 	swap = ((data & 0xffULL) << 56) |  in __read_8_sw()
94 		((data & (0xffULL << 8)) << 40) |  in __read_8_sw()
95 		((data & (0xffULL << 16)) << 24) |  in __read_8_sw()
96 		((data & (0xffULL << 24)) << 8) |  in __read_8_sw()
97 		((data & (0xffULL << 32)) >> 8) |  in __read_8_sw()
98 		((data & (0xffULL << 40)) >> 24) |  in __read_8_sw()
99 		((data & (0xffULL << 48)) >> 40) |  in __read_8_sw()
100 		((data & (0xffULL << 56)) >> 56);  in __read_8_sw()
107 	unsigned int data = *(unsigned int *)ptr;  in __read_4()  local
109 	return data;  in __read_4()
114 	unsigned int data = *(unsigned int *)ptr;  in __read_4_sw()  local
117 	swap = ((data & 0xffULL) << 24) |  in __read_4_sw()
118 		((data & (0xffULL << 8)) << 8) |  in __read_4_sw()
119 		((data & (0xffULL << 16)) >> 8) |  in __read_4_sw()
120 		((data & (0xffULL << 24)) >> 24);  in __read_4_sw()
127 	return kbuf->read_8(ptr);  in read_8()
132 	return kbuf->read_4(ptr);  in read_4()
137 	return kbuf->read_8(ptr);  in __read_long_8()
142 	return kbuf->read_4(ptr);  in __read_long_4()
147 	return kbuf->read_long(kbuf, ptr);  in read_long()
152 	return (unsigned long)ptr - (unsigned long)kbuf->data;  in calc_index()
158  * kbuffer_alloc - allocat a new kbuffer
159  * @size;	enum to denote size of word
165 kbuffer_alloc(enum kbuffer_long_size size, enum kbuffer_endian endian)  in kbuffer_alloc()  argument
170 	switch (size) {  in kbuffer_alloc()
194 	kbuf->flags = flags;  in kbuffer_alloc()
197 		kbuf->flags |= KBUFFER_FL_HOST_BIG_ENDIAN;  in kbuffer_alloc()
200 		kbuf->read_8 = __read_8_sw;  in kbuffer_alloc()
201 		kbuf->read_4 = __read_4_sw;  in kbuffer_alloc()
203 		kbuf->read_8 = __read_8;  in kbuffer_alloc()
204 		kbuf->read_4 = __read_4;  in kbuffer_alloc()
207 	if (kbuf->flags & KBUFFER_FL_LONG_8)  in kbuffer_alloc()
208 		kbuf->read_long = __read_long_8;  in kbuffer_alloc()
210 		kbuf->read_long = __read_long_4;  in kbuffer_alloc()
213 	kbuf->next_event = __next_event;  in kbuffer_alloc()
218 /** kbuffer_free - free an allocated kbuffer
231 	if (kbuf->flags & KBUFFER_FL_BIG_ENDIAN)  in type4host()
240 	if (kbuf->flags & KBUFFER_FL_BIG_ENDIAN)  in len4host()
249 	if (kbuf->flags & KBUFFER_FL_BIG_ENDIAN)  in type_len4host()
250 		return (type_len_ts >> 27) & ((1 << 5) - 1);  in type_len4host()
252 		return type_len_ts & ((1 << 5) - 1);  in type_len4host()
258 	if (kbuf->flags & KBUFFER_FL_BIG_ENDIAN)  in ts4host()
259 		return type_len_ts & ((1 << 27) - 1);  in ts4host()
283 	void *ptr = kbuf->data + kbuf->curr;  in old_update_pointers()
294 		kbuf->next = kbuf->size;  in old_update_pointers()
308 		kbuf->curr = kbuf->size;  in old_update_pointers()
309 		kbuf->next = kbuf->size;  in old_update_pointers()
310 		kbuf->index = kbuf->size;  in old_update_pointers()
311 		return -1;  in old_update_pointers()
317 			length -= 4;  in old_update_pointers()
323 	kbuf->timestamp += delta;  in old_update_pointers()
324 	kbuf->index = calc_index(kbuf, ptr);  in old_update_pointers()
325 	kbuf->next = kbuf->index + length;  in old_update_pointers()
335 		kbuf->curr = kbuf->next;  in __old_next_event()
336 		if (kbuf->next >= kbuf->size)  in __old_next_event()
337 			return -1;  in __old_next_event()
345 translate_data(struct kbuffer *kbuf, void *data, void **rptr,  in translate_data()  argument
352 	type_len_ts = read_4(kbuf, data);  in translate_data()
353 	data += 4;  in translate_data()
360 		*length = read_4(kbuf, data);  in translate_data()
365 		extend = read_4(kbuf, data);  in translate_data()
366 		data += 4;  in translate_data()
374 		*length = read_4(kbuf, data) - 4;  in translate_data()
376 		data += 4;  in translate_data()
383 	*rptr = data;  in translate_data()
393 	void *ptr = kbuf->data + kbuf->curr;  in update_pointers()
398 		kbuf->timestamp = delta;  in update_pointers()
400 		kbuf->timestamp += delta;  in update_pointers()
402 	kbuf->index = calc_index(kbuf, ptr);  in update_pointers()
403 	kbuf->next = kbuf->index + length;  in update_pointers()
409  * kbuffer_translate_data - read raw data to get a record
411  * @data:	The raw data to read
412  * @size:	Address to store the size of the event data.
414  * Returns a pointer to the event data. To determine the entire
415  * record size (record metadata + data) just add the difference between
416  * @data and the returned value to @size.
418 void *kbuffer_translate_data(int swap, void *data, unsigned int *size)  in kbuffer_translate_data()  argument
436 	type_len = translate_data(&kbuf, data, &ptr, &delta, &length);  in kbuffer_translate_data()
444 	*size = length;  in kbuffer_translate_data()
454 		kbuf->curr = kbuf->next;  in __next_event()
455 		if (kbuf->next >= kbuf->size)  in __next_event()
456 			return -1;  in __next_event()
467 	return kbuf->next_event(kbuf);  in next_event()
471  * kbuffer_next_event - increment the current pointer
479  * Returns the data of the next event if a new event exists on the subbuffer,
486 	if (!kbuf || !kbuf->subbuffer)  in kbuffer_next_event()
494 		*ts = kbuf->timestamp;  in kbuffer_next_event()
496 	return kbuf->data + kbuf->index;  in kbuffer_next_event()
500  * kbuffer_load_subbuffer - load a new subbuffer into the kbuffer
508  * Returns 0 on succes, -1 otherwise.
516 		return -1;  in kbuffer_load_subbuffer()
518 	kbuf->subbuffer = subbuffer;  in kbuffer_load_subbuffer()
520 	kbuf->timestamp = read_8(kbuf, ptr);  in kbuffer_load_subbuffer()
523 	kbuf->curr = 0;  in kbuffer_load_subbuffer()
525 	if (kbuf->flags & KBUFFER_FL_LONG_8)  in kbuffer_load_subbuffer()
526 		kbuf->start = 16;  in kbuffer_load_subbuffer()
528 		kbuf->start = 12;  in kbuffer_load_subbuffer()
530 	kbuf->data = subbuffer + kbuf->start;  in kbuffer_load_subbuffer()
533 	kbuf->size = (unsigned int)flags & COMMIT_MASK;  in kbuffer_load_subbuffer()
537 			ptr = kbuf->data + kbuf->size;  in kbuffer_load_subbuffer()
538 			kbuf->lost_events = read_long(kbuf, ptr);  in kbuffer_load_subbuffer()
540 			kbuf->lost_events = -1;  in kbuffer_load_subbuffer()
542 		kbuf->lost_events = 0;  in kbuffer_load_subbuffer()
544 	kbuf->index = 0;  in kbuffer_load_subbuffer()
545 	kbuf->next = 0;  in kbuffer_load_subbuffer()
553  * kbuffer_subbuf_timestamp - read the timestamp from a sub buffer
561 	return kbuf->read_8(subbuf);  in kbuffer_subbuf_timestamp()
565  * kbuffer_ptr_delta - read the delta field from a record
581  * kbuffer_read_event - read the next event in the kbuffer subbuffer
585  * Returns a pointer to the data part of the current event.
590 	if (!kbuf || !kbuf->subbuffer)  in kbuffer_read_event()
593 	if (kbuf->curr >= kbuf->size)  in kbuffer_read_event()
597 		*ts = kbuf->timestamp;  in kbuffer_read_event()
598 	return kbuf->data + kbuf->index;  in kbuffer_read_event()
602  * kbuffer_timestamp - Return the timestamp of the current event
609 	return kbuf->timestamp;  in kbuffer_timestamp()
613  * kbuffer_read_at_offset - read the event that is at offset
621  * Returns the data of the record that is at @offset. Note, @offset does
627  * data and timestamp, and kbuffer_next_event() will increment from
633 	void *data;  in kbuffer_read_at_offset()  local
635 	if (offset < kbuf->start)  in kbuffer_read_at_offset()
638 		offset -= kbuf->start;  in kbuffer_read_at_offset()
641 	kbuffer_load_subbuffer(kbuf, kbuf->subbuffer);  in kbuffer_read_at_offset()
642 	data = kbuffer_read_event(kbuf, ts);  in kbuffer_read_at_offset()
644 	while (kbuf->curr < offset) {  in kbuffer_read_at_offset()
645 		data = kbuffer_next_event(kbuf, ts);  in kbuffer_read_at_offset()
646 		if (!data)  in kbuffer_read_at_offset()
650 	return data;  in kbuffer_read_at_offset()
654  * kbuffer_subbuffer_size - the size of the loaded subbuffer
657  * Returns the size of the subbuffer. Note, this size is
663 	return kbuf->size;  in kbuffer_subbuffer_size()
667  * kbuffer_curr_index - Return the index of the record
670  * Returns the index from the start of the data part of
678 	return kbuf->curr;  in kbuffer_curr_index()
682  * kbuffer_curr_offset - Return the offset of the record
690 	return kbuf->curr + kbuf->start;  in kbuffer_curr_offset()
694  * kbuffer_event_size - return the size of the event data
697  * Returns the size of the event data (the payload not counting
698  * the meta data of the record) of the current event.
702 	return kbuf->next - kbuf->index;  in kbuffer_event_size()
706  * kbuffer_curr_size - return the size of the entire record
709  * Returns the size of the entire record (meta data and payload)
714 	return kbuf->next - kbuf->curr;  in kbuffer_curr_size()
718  * kbuffer_missed_events - return the # of missed events from last event.
729 	if (kbuf->curr)  in kbuffer_missed_events()
732 	return kbuf->lost_events;  in kbuffer_missed_events()
736  * kbuffer_set_old_forma - set the kbuffer to use the old format parsing
746 	kbuf->flags |= KBUFFER_FL_OLD_FORMAT;  in kbuffer_set_old_format()
748 	kbuf->next_event = __old_next_event;  in kbuffer_set_old_format()
752  * kbuffer_start_of_data - return offset of where data starts on subbuffer
755  * Returns the location on the subbuffer where the data starts.
759 	return kbuf->start;  in kbuffer_start_of_data()
763  * kbuffer_raw_get - get raw buffer info
769  * Expects to have info->next set to what it will read.
771  * @info->next will be updated to the next element.
773  * data and NULL will be returned if it is.
781 	unsigned int size;  in kbuffer_raw_get()  local
784 	void *ptr = info->next;  in kbuffer_raw_get()
789 	if (kbuf->flags & KBUFFER_FL_LONG_8)  in kbuffer_raw_get()
795 	size = (unsigned int)flags & COMMIT_MASK;  in kbuffer_raw_get()
797 	if (ptr < subbuf || ptr >= subbuf + start + size)  in kbuffer_raw_get()
802 	info->next = ptr + length;  in kbuffer_raw_get()
804 	info->type = type_len;  in kbuffer_raw_get()
805 	info->delta = delta;  in kbuffer_raw_get()
806 	info->length = length;  in kbuffer_raw_get()