1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/* Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved */
3
4#include <linux/kernel.h>
5#include <linux/slab.h>
6#include <linux/list.h>
7#include <linux/errno.h>
8#include <linux/refcount.h>
9
10#include "item.h"
11#include "core_acl_flex_keys.h"
12
13/* For the purpose of the driver, define an internal storage scratchpad
14 * that will be used to store key/mask values. For each defined element type
15 * define an internal storage geometry.
16 *
17 * When adding new elements, MLXSW_AFK_ELEMENT_STORAGE_SIZE must be increased
18 * accordingly.
19 */
20static const struct mlxsw_afk_element_info mlxsw_afk_element_infos[] = {
21	MLXSW_AFK_ELEMENT_INFO_U32(SRC_SYS_PORT, 0x00, 16, 16),
22	MLXSW_AFK_ELEMENT_INFO_BUF(DMAC_32_47, 0x04, 2),
23	MLXSW_AFK_ELEMENT_INFO_BUF(DMAC_0_31, 0x06, 4),
24	MLXSW_AFK_ELEMENT_INFO_BUF(SMAC_32_47, 0x0A, 2),
25	MLXSW_AFK_ELEMENT_INFO_BUF(SMAC_0_31, 0x0C, 4),
26	MLXSW_AFK_ELEMENT_INFO_U32(ETHERTYPE, 0x00, 0, 16),
27	MLXSW_AFK_ELEMENT_INFO_U32(IP_PROTO, 0x10, 0, 8),
28	MLXSW_AFK_ELEMENT_INFO_U32(VID, 0x10, 8, 12),
29	MLXSW_AFK_ELEMENT_INFO_U32(PCP, 0x10, 20, 3),
30	MLXSW_AFK_ELEMENT_INFO_U32(TCP_FLAGS, 0x10, 23, 9),
31	MLXSW_AFK_ELEMENT_INFO_U32(DST_L4_PORT, 0x14, 0, 16),
32	MLXSW_AFK_ELEMENT_INFO_U32(SRC_L4_PORT, 0x14, 16, 16),
33	MLXSW_AFK_ELEMENT_INFO_U32(IP_TTL_, 0x18, 0, 8),
34	MLXSW_AFK_ELEMENT_INFO_U32(IP_ECN, 0x18, 9, 2),
35	MLXSW_AFK_ELEMENT_INFO_U32(IP_DSCP, 0x18, 11, 6),
36	MLXSW_AFK_ELEMENT_INFO_U32(VIRT_ROUTER, 0x18, 17, 12),
37	MLXSW_AFK_ELEMENT_INFO_BUF(SRC_IP_96_127, 0x20, 4),
38	MLXSW_AFK_ELEMENT_INFO_BUF(SRC_IP_64_95, 0x24, 4),
39	MLXSW_AFK_ELEMENT_INFO_BUF(SRC_IP_32_63, 0x28, 4),
40	MLXSW_AFK_ELEMENT_INFO_BUF(SRC_IP_0_31, 0x2C, 4),
41	MLXSW_AFK_ELEMENT_INFO_BUF(DST_IP_96_127, 0x30, 4),
42	MLXSW_AFK_ELEMENT_INFO_BUF(DST_IP_64_95, 0x34, 4),
43	MLXSW_AFK_ELEMENT_INFO_BUF(DST_IP_32_63, 0x38, 4),
44	MLXSW_AFK_ELEMENT_INFO_BUF(DST_IP_0_31, 0x3C, 4),
45	MLXSW_AFK_ELEMENT_INFO_U32(FDB_MISS, 0x40, 0, 1),
46	MLXSW_AFK_ELEMENT_INFO_U32(L4_PORT_RANGE, 0x40, 1, 16),
47	MLXSW_AFK_ELEMENT_INFO_U32(VIRT_ROUTER_0_3, 0x40, 17, 4),
48	MLXSW_AFK_ELEMENT_INFO_U32(VIRT_ROUTER_4_7, 0x40, 21, 4),
49	MLXSW_AFK_ELEMENT_INFO_U32(VIRT_ROUTER_MSB, 0x40, 25, 4),
50};
51
52struct mlxsw_afk {
53	struct list_head key_info_list;
54	unsigned int max_blocks;
55	const struct mlxsw_afk_ops *ops;
56	const struct mlxsw_afk_block *blocks;
57	unsigned int blocks_count;
58};
59
60static bool mlxsw_afk_blocks_check(struct mlxsw_afk *mlxsw_afk)
61{
62	int i;
63	int j;
64
65	for (i = 0; i < mlxsw_afk->blocks_count; i++) {
66		const struct mlxsw_afk_block *block = &mlxsw_afk->blocks[i];
67
68		for (j = 0; j < block->instances_count; j++) {
69			const struct mlxsw_afk_element_info *elinfo;
70			struct mlxsw_afk_element_inst *elinst;
71
72			elinst = &block->instances[j];
73			elinfo = &mlxsw_afk_element_infos[elinst->element];
74			if (elinst->type != elinfo->type ||
75			    (!elinst->avoid_size_check &&
76			     elinst->item.size.bits !=
77			     elinfo->item.size.bits))
78				return false;
79		}
80	}
81	return true;
82}
83
84struct mlxsw_afk *mlxsw_afk_create(unsigned int max_blocks,
85				   const struct mlxsw_afk_ops *ops)
86{
87	struct mlxsw_afk *mlxsw_afk;
88
89	mlxsw_afk = kzalloc(sizeof(*mlxsw_afk), GFP_KERNEL);
90	if (!mlxsw_afk)
91		return NULL;
92	INIT_LIST_HEAD(&mlxsw_afk->key_info_list);
93	mlxsw_afk->max_blocks = max_blocks;
94	mlxsw_afk->ops = ops;
95	mlxsw_afk->blocks = ops->blocks;
96	mlxsw_afk->blocks_count = ops->blocks_count;
97	WARN_ON(!mlxsw_afk_blocks_check(mlxsw_afk));
98	return mlxsw_afk;
99}
100EXPORT_SYMBOL(mlxsw_afk_create);
101
102void mlxsw_afk_destroy(struct mlxsw_afk *mlxsw_afk)
103{
104	WARN_ON(!list_empty(&mlxsw_afk->key_info_list));
105	kfree(mlxsw_afk);
106}
107EXPORT_SYMBOL(mlxsw_afk_destroy);
108
109struct mlxsw_afk_key_info {
110	struct list_head list;
111	refcount_t ref_count;
112	unsigned int blocks_count;
113	int element_to_block[MLXSW_AFK_ELEMENT_MAX]; /* index is element, value
114						      * is index inside "blocks"
115						      */
116	struct mlxsw_afk_element_usage elusage;
117	const struct mlxsw_afk_block *blocks[];
118};
119
120static bool
121mlxsw_afk_key_info_elements_eq(struct mlxsw_afk_key_info *key_info,
122			       struct mlxsw_afk_element_usage *elusage)
123{
124	return memcmp(&key_info->elusage, elusage, sizeof(*elusage)) == 0;
125}
126
127static struct mlxsw_afk_key_info *
128mlxsw_afk_key_info_find(struct mlxsw_afk *mlxsw_afk,
129			struct mlxsw_afk_element_usage *elusage)
130{
131	struct mlxsw_afk_key_info *key_info;
132
133	list_for_each_entry(key_info, &mlxsw_afk->key_info_list, list) {
134		if (mlxsw_afk_key_info_elements_eq(key_info, elusage))
135			return key_info;
136	}
137	return NULL;
138}
139
140struct mlxsw_afk_picker {
141	DECLARE_BITMAP(element, MLXSW_AFK_ELEMENT_MAX);
142	DECLARE_BITMAP(chosen_element, MLXSW_AFK_ELEMENT_MAX);
143	unsigned int total;
144};
145
146static void mlxsw_afk_picker_count_hits(struct mlxsw_afk *mlxsw_afk,
147					struct mlxsw_afk_picker *picker,
148					enum mlxsw_afk_element element)
149{
150	int i;
151	int j;
152
153	for (i = 0; i < mlxsw_afk->blocks_count; i++) {
154		const struct mlxsw_afk_block *block = &mlxsw_afk->blocks[i];
155
156		for (j = 0; j < block->instances_count; j++) {
157			struct mlxsw_afk_element_inst *elinst;
158
159			elinst = &block->instances[j];
160			if (elinst->element == element) {
161				__set_bit(element, picker[i].element);
162				picker[i].total++;
163			}
164		}
165	}
166}
167
168static void mlxsw_afk_picker_subtract_hits(struct mlxsw_afk *mlxsw_afk,
169					   struct mlxsw_afk_picker *picker,
170					   int block_index)
171{
172	DECLARE_BITMAP(hits_element, MLXSW_AFK_ELEMENT_MAX);
173	int i;
174	int j;
175
176	memcpy(&hits_element, &picker[block_index].element,
177	       sizeof(hits_element));
178
179	for (i = 0; i < mlxsw_afk->blocks_count; i++) {
180		for_each_set_bit(j, hits_element, MLXSW_AFK_ELEMENT_MAX) {
181			if (__test_and_clear_bit(j, picker[i].element))
182				picker[i].total--;
183		}
184	}
185}
186
187static int mlxsw_afk_picker_most_hits_get(struct mlxsw_afk *mlxsw_afk,
188					  struct mlxsw_afk_picker *picker)
189{
190	int most_index = -EINVAL; /* Should never happen to return this */
191	int most_hits = 0;
192	int i;
193
194	for (i = 0; i < mlxsw_afk->blocks_count; i++) {
195		if (picker[i].total > most_hits) {
196			most_hits = picker[i].total;
197			most_index = i;
198		}
199	}
200	return most_index;
201}
202
203static int mlxsw_afk_picker_key_info_add(struct mlxsw_afk *mlxsw_afk,
204					 struct mlxsw_afk_picker *picker,
205					 int block_index,
206					 struct mlxsw_afk_key_info *key_info)
207{
208	enum mlxsw_afk_element element;
209
210	if (key_info->blocks_count == mlxsw_afk->max_blocks)
211		return -EINVAL;
212
213	for_each_set_bit(element, picker[block_index].chosen_element,
214			 MLXSW_AFK_ELEMENT_MAX) {
215		key_info->element_to_block[element] = key_info->blocks_count;
216		mlxsw_afk_element_usage_add(&key_info->elusage, element);
217	}
218
219	key_info->blocks[key_info->blocks_count] =
220					&mlxsw_afk->blocks[block_index];
221	key_info->blocks_count++;
222	return 0;
223}
224
225static int mlxsw_afk_keys_fill(struct mlxsw_afk *mlxsw_afk,
226			       unsigned long *chosen_blocks_bm,
227			       struct mlxsw_afk_picker *picker,
228			       struct mlxsw_afk_key_info *key_info)
229{
230	int i, err;
231
232	/* First fill only key blocks with high_entropy. */
233	for_each_set_bit(i, chosen_blocks_bm, mlxsw_afk->blocks_count) {
234		if (!mlxsw_afk->blocks[i].high_entropy)
235			continue;
236
237		err = mlxsw_afk_picker_key_info_add(mlxsw_afk, picker, i,
238						    key_info);
239		if (err)
240			return err;
241		__clear_bit(i, chosen_blocks_bm);
242	}
243
244	/* Fill the rest of key blocks. */
245	for_each_set_bit(i, chosen_blocks_bm, mlxsw_afk->blocks_count) {
246		err = mlxsw_afk_picker_key_info_add(mlxsw_afk, picker, i,
247						    key_info);
248		if (err)
249			return err;
250	}
251
252	return 0;
253}
254
255static int mlxsw_afk_picker(struct mlxsw_afk *mlxsw_afk,
256			    struct mlxsw_afk_key_info *key_info,
257			    struct mlxsw_afk_element_usage *elusage)
258{
259	DECLARE_BITMAP(elusage_chosen, MLXSW_AFK_ELEMENT_MAX) = {0};
260	struct mlxsw_afk_picker *picker;
261	unsigned long *chosen_blocks_bm;
262	enum mlxsw_afk_element element;
263	int err;
264
265	picker = kcalloc(mlxsw_afk->blocks_count, sizeof(*picker), GFP_KERNEL);
266	if (!picker)
267		return -ENOMEM;
268
269	chosen_blocks_bm = bitmap_zalloc(mlxsw_afk->blocks_count, GFP_KERNEL);
270	if (!chosen_blocks_bm) {
271		err = -ENOMEM;
272		goto err_bitmap_alloc;
273	}
274
275	/* Since the same elements could be present in multiple blocks,
276	 * we must find out optimal block list in order to make the
277	 * block count as low as possible.
278	 *
279	 * First, we count hits. We go over all available blocks and count
280	 * how many of requested elements are covered by each.
281	 *
282	 * Then in loop, we find block with most hits and add it to
283	 * output key_info. Then we have to subtract this block hits so
284	 * the next iteration will find most suitable block for
285	 * the rest of requested elements.
286	 */
287
288	mlxsw_afk_element_usage_for_each(element, elusage)
289		mlxsw_afk_picker_count_hits(mlxsw_afk, picker, element);
290
291	do {
292		int block_index;
293
294		block_index = mlxsw_afk_picker_most_hits_get(mlxsw_afk, picker);
295		if (block_index < 0) {
296			err = block_index;
297			goto out;
298		}
299
300		__set_bit(block_index, chosen_blocks_bm);
301
302		bitmap_copy(picker[block_index].chosen_element,
303			    picker[block_index].element, MLXSW_AFK_ELEMENT_MAX);
304
305		bitmap_or(elusage_chosen, elusage_chosen,
306			  picker[block_index].chosen_element,
307			  MLXSW_AFK_ELEMENT_MAX);
308
309		mlxsw_afk_picker_subtract_hits(mlxsw_afk, picker, block_index);
310
311	} while (!bitmap_equal(elusage_chosen, elusage->usage,
312			       MLXSW_AFK_ELEMENT_MAX));
313
314	err = mlxsw_afk_keys_fill(mlxsw_afk, chosen_blocks_bm, picker,
315				  key_info);
316out:
317	bitmap_free(chosen_blocks_bm);
318err_bitmap_alloc:
319	kfree(picker);
320	return err;
321}
322
323static struct mlxsw_afk_key_info *
324mlxsw_afk_key_info_create(struct mlxsw_afk *mlxsw_afk,
325			  struct mlxsw_afk_element_usage *elusage)
326{
327	struct mlxsw_afk_key_info *key_info;
328	int err;
329
330	key_info = kzalloc(struct_size(key_info, blocks, mlxsw_afk->max_blocks),
331			   GFP_KERNEL);
332	if (!key_info)
333		return ERR_PTR(-ENOMEM);
334	err = mlxsw_afk_picker(mlxsw_afk, key_info, elusage);
335	if (err)
336		goto err_picker;
337	list_add(&key_info->list, &mlxsw_afk->key_info_list);
338	refcount_set(&key_info->ref_count, 1);
339	return key_info;
340
341err_picker:
342	kfree(key_info);
343	return ERR_PTR(err);
344}
345
346static void mlxsw_afk_key_info_destroy(struct mlxsw_afk_key_info *key_info)
347{
348	list_del(&key_info->list);
349	kfree(key_info);
350}
351
352struct mlxsw_afk_key_info *
353mlxsw_afk_key_info_get(struct mlxsw_afk *mlxsw_afk,
354		       struct mlxsw_afk_element_usage *elusage)
355{
356	struct mlxsw_afk_key_info *key_info;
357
358	key_info = mlxsw_afk_key_info_find(mlxsw_afk, elusage);
359	if (key_info) {
360		refcount_inc(&key_info->ref_count);
361		return key_info;
362	}
363	return mlxsw_afk_key_info_create(mlxsw_afk, elusage);
364}
365EXPORT_SYMBOL(mlxsw_afk_key_info_get);
366
367void mlxsw_afk_key_info_put(struct mlxsw_afk_key_info *key_info)
368{
369	if (!refcount_dec_and_test(&key_info->ref_count))
370		return;
371	mlxsw_afk_key_info_destroy(key_info);
372}
373EXPORT_SYMBOL(mlxsw_afk_key_info_put);
374
375bool mlxsw_afk_key_info_subset(struct mlxsw_afk_key_info *key_info,
376			       struct mlxsw_afk_element_usage *elusage)
377{
378	return mlxsw_afk_element_usage_subset(elusage, &key_info->elusage);
379}
380EXPORT_SYMBOL(mlxsw_afk_key_info_subset);
381
382static const struct mlxsw_afk_element_inst *
383mlxsw_afk_block_elinst_get(const struct mlxsw_afk_block *block,
384			   enum mlxsw_afk_element element)
385{
386	int i;
387
388	for (i = 0; i < block->instances_count; i++) {
389		struct mlxsw_afk_element_inst *elinst;
390
391		elinst = &block->instances[i];
392		if (elinst->element == element)
393			return elinst;
394	}
395	return NULL;
396}
397
398static const struct mlxsw_afk_element_inst *
399mlxsw_afk_key_info_elinst_get(struct mlxsw_afk_key_info *key_info,
400			      enum mlxsw_afk_element element,
401			      int *p_block_index)
402{
403	const struct mlxsw_afk_element_inst *elinst;
404	const struct mlxsw_afk_block *block;
405	int block_index;
406
407	if (WARN_ON(!test_bit(element, key_info->elusage.usage)))
408		return NULL;
409	block_index = key_info->element_to_block[element];
410	block = key_info->blocks[block_index];
411
412	elinst = mlxsw_afk_block_elinst_get(block, element);
413	if (WARN_ON(!elinst))
414		return NULL;
415
416	*p_block_index = block_index;
417	return elinst;
418}
419
420u16
421mlxsw_afk_key_info_block_encoding_get(const struct mlxsw_afk_key_info *key_info,
422				      int block_index)
423{
424	return key_info->blocks[block_index]->encoding;
425}
426EXPORT_SYMBOL(mlxsw_afk_key_info_block_encoding_get);
427
428unsigned int
429mlxsw_afk_key_info_blocks_count_get(const struct mlxsw_afk_key_info *key_info)
430{
431	return key_info->blocks_count;
432}
433EXPORT_SYMBOL(mlxsw_afk_key_info_blocks_count_get);
434
435void mlxsw_afk_values_add_u32(struct mlxsw_afk_element_values *values,
436			      enum mlxsw_afk_element element,
437			      u32 key_value, u32 mask_value)
438{
439	const struct mlxsw_afk_element_info *elinfo =
440				&mlxsw_afk_element_infos[element];
441	const struct mlxsw_item *storage_item = &elinfo->item;
442
443	if (!mask_value)
444		return;
445	if (WARN_ON(elinfo->type != MLXSW_AFK_ELEMENT_TYPE_U32))
446		return;
447	__mlxsw_item_set32(values->storage.key, storage_item, 0, key_value);
448	__mlxsw_item_set32(values->storage.mask, storage_item, 0, mask_value);
449	mlxsw_afk_element_usage_add(&values->elusage, element);
450}
451EXPORT_SYMBOL(mlxsw_afk_values_add_u32);
452
453void mlxsw_afk_values_add_buf(struct mlxsw_afk_element_values *values,
454			      enum mlxsw_afk_element element,
455			      const char *key_value, const char *mask_value,
456			      unsigned int len)
457{
458	const struct mlxsw_afk_element_info *elinfo =
459				&mlxsw_afk_element_infos[element];
460	const struct mlxsw_item *storage_item = &elinfo->item;
461
462	if (!memchr_inv(mask_value, 0, len)) /* If mask is zero */
463		return;
464	if (WARN_ON(elinfo->type != MLXSW_AFK_ELEMENT_TYPE_BUF) ||
465	    WARN_ON(elinfo->item.size.bytes != len))
466		return;
467	__mlxsw_item_memcpy_to(values->storage.key, key_value,
468			       storage_item, 0);
469	__mlxsw_item_memcpy_to(values->storage.mask, mask_value,
470			       storage_item, 0);
471	mlxsw_afk_element_usage_add(&values->elusage, element);
472}
473EXPORT_SYMBOL(mlxsw_afk_values_add_buf);
474
475static void mlxsw_sp_afk_encode_u32(const struct mlxsw_item *storage_item,
476				    const struct mlxsw_item *output_item,
477				    char *storage, char *output, int diff)
478{
479	u32 value;
480
481	value = __mlxsw_item_get32(storage, storage_item, 0);
482	__mlxsw_item_set32(output, output_item, 0, value + diff);
483}
484
485static void mlxsw_sp_afk_encode_buf(const struct mlxsw_item *storage_item,
486				    const struct mlxsw_item *output_item,
487				    char *storage, char *output)
488{
489	char *storage_data = __mlxsw_item_data(storage, storage_item, 0);
490	char *output_data = __mlxsw_item_data(output, output_item, 0);
491	size_t len = output_item->size.bytes;
492
493	memcpy(output_data, storage_data, len);
494}
495
496static void
497mlxsw_sp_afk_encode_one(const struct mlxsw_afk_element_inst *elinst,
498			char *output, char *storage, int u32_diff)
499{
500	const struct mlxsw_item *output_item = &elinst->item;
501	const struct mlxsw_afk_element_info *elinfo;
502	const struct mlxsw_item *storage_item;
503
504	elinfo = &mlxsw_afk_element_infos[elinst->element];
505	storage_item = &elinfo->item;
506	if (elinst->type == MLXSW_AFK_ELEMENT_TYPE_U32)
507		mlxsw_sp_afk_encode_u32(storage_item, output_item,
508					storage, output, u32_diff);
509	else if (elinst->type == MLXSW_AFK_ELEMENT_TYPE_BUF)
510		mlxsw_sp_afk_encode_buf(storage_item, output_item,
511					storage, output);
512}
513
514#define MLXSW_SP_AFK_KEY_BLOCK_MAX_SIZE 16
515
516void mlxsw_afk_encode(struct mlxsw_afk *mlxsw_afk,
517		      struct mlxsw_afk_key_info *key_info,
518		      struct mlxsw_afk_element_values *values,
519		      char *key, char *mask)
520{
521	unsigned int blocks_count =
522			mlxsw_afk_key_info_blocks_count_get(key_info);
523	char block_mask[MLXSW_SP_AFK_KEY_BLOCK_MAX_SIZE];
524	char block_key[MLXSW_SP_AFK_KEY_BLOCK_MAX_SIZE];
525	const struct mlxsw_afk_element_inst *elinst;
526	enum mlxsw_afk_element element;
527	int block_index, i;
528
529	for (i = 0; i < blocks_count; i++) {
530		memset(block_key, 0, MLXSW_SP_AFK_KEY_BLOCK_MAX_SIZE);
531		memset(block_mask, 0, MLXSW_SP_AFK_KEY_BLOCK_MAX_SIZE);
532
533		mlxsw_afk_element_usage_for_each(element, &values->elusage) {
534			elinst = mlxsw_afk_key_info_elinst_get(key_info,
535							       element,
536							       &block_index);
537			if (!elinst || block_index != i)
538				continue;
539
540			mlxsw_sp_afk_encode_one(elinst, block_key,
541						values->storage.key,
542						elinst->u32_key_diff);
543			mlxsw_sp_afk_encode_one(elinst, block_mask,
544						values->storage.mask, 0);
545		}
546
547		mlxsw_afk->ops->encode_block(key, i, block_key);
548		mlxsw_afk->ops->encode_block(mask, i, block_mask);
549	}
550}
551EXPORT_SYMBOL(mlxsw_afk_encode);
552
553void mlxsw_afk_clear(struct mlxsw_afk *mlxsw_afk, char *key,
554		     int block_start, int block_end)
555{
556	int i;
557
558	for (i = block_start; i <= block_end; i++)
559		mlxsw_afk->ops->clear_block(key, i);
560}
561EXPORT_SYMBOL(mlxsw_afk_clear);
562