1/*
2 * Copyright(c) 2017 Intel Corporation.
3 *
4 * This file is provided under a dual BSD/GPLv2 license.  When using or
5 * redistributing this file, you may do so under either license.
6 *
7 * GPL LICENSE SUMMARY
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of version 2 of the GNU General Public License as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * BSD LICENSE
19 *
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
22 * are met:
23 *
24 *  - Redistributions of source code must retain the above copyright
25 *    notice, this list of conditions and the following disclaimer.
26 *  - Redistributions in binary form must reproduce the above copyright
27 *    notice, this list of conditions and the following disclaimer in
28 *    the documentation and/or other materials provided with the
29 *    distribution.
30 *  - Neither the name of Intel Corporation nor the names of its
31 *    contributors may be used to endorse or promote products derived
32 *    from this software without specific prior written permission.
33 *
34 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45 *
46 */
47
48/*
49 * This file contains OPA VNIC encapsulation/decapsulation function.
50 */
51
52#include <linux/if_ether.h>
53#include <linux/if_vlan.h>
54
55#include "opa_vnic_internal.h"
56
57/* OPA 16B Header fields */
58#define OPA_16B_LID_MASK        0xFFFFFull
59#define OPA_16B_SLID_HIGH_SHFT  8
60#define OPA_16B_SLID_MASK       0xF00ull
61#define OPA_16B_DLID_MASK       0xF000ull
62#define OPA_16B_DLID_HIGH_SHFT  12
63#define OPA_16B_LEN_SHFT        20
64#define OPA_16B_SC_SHFT         20
65#define OPA_16B_RC_SHFT         25
66#define OPA_16B_PKEY_SHFT       16
67
68#define OPA_VNIC_L4_HDR_SHFT    16
69
70/* L2+L4 hdr len is 20 bytes (5 quad words) */
71#define OPA_VNIC_HDR_QW_LEN   5
72
73static inline void opa_vnic_make_header(u8 *hdr, u32 slid, u32 dlid, u16 len,
74					u16 pkey, u16 entropy, u8 sc, u8 rc,
75					u8 l4_type, u16 l4_hdr)
76{
77	/* h[1]: LT=1, 16B L2=10 */
78	u32 h[OPA_VNIC_HDR_QW_LEN] = {0, 0xc0000000, 0, 0, 0};
79
80	h[2] = l4_type;
81	h[3] = entropy;
82	h[4] = l4_hdr << OPA_VNIC_L4_HDR_SHFT;
83
84	/* Extract and set 4 upper bits and 20 lower bits of the lids */
85	h[0] |= (slid & OPA_16B_LID_MASK);
86	h[2] |= ((slid >> (20 - OPA_16B_SLID_HIGH_SHFT)) & OPA_16B_SLID_MASK);
87
88	h[1] |= (dlid & OPA_16B_LID_MASK);
89	h[2] |= ((dlid >> (20 - OPA_16B_DLID_HIGH_SHFT)) & OPA_16B_DLID_MASK);
90
91	h[0] |= (len << OPA_16B_LEN_SHFT);
92	h[1] |= (rc << OPA_16B_RC_SHFT);
93	h[1] |= (sc << OPA_16B_SC_SHFT);
94	h[2] |= ((u32)pkey << OPA_16B_PKEY_SHFT);
95
96	memcpy(hdr, h, OPA_VNIC_HDR_LEN);
97}
98
99/*
100 * Using a simple hash table for mac table implementation with the last octet
101 * of mac address as a key.
102 */
103static void opa_vnic_free_mac_tbl(struct hlist_head *mactbl)
104{
105	struct opa_vnic_mac_tbl_node *node;
106	struct hlist_node *tmp;
107	int bkt;
108
109	if (!mactbl)
110		return;
111
112	vnic_hash_for_each_safe(mactbl, bkt, tmp, node, hlist) {
113		hash_del(&node->hlist);
114		kfree(node);
115	}
116	kfree(mactbl);
117}
118
119static struct hlist_head *opa_vnic_alloc_mac_tbl(void)
120{
121	u32 size = sizeof(struct hlist_head) * OPA_VNIC_MAC_TBL_SIZE;
122	struct hlist_head *mactbl;
123
124	mactbl = kzalloc(size, GFP_KERNEL);
125	if (!mactbl)
126		return ERR_PTR(-ENOMEM);
127
128	vnic_hash_init(mactbl);
129	return mactbl;
130}
131
132/* opa_vnic_release_mac_tbl - empty and free the mac table */
133void opa_vnic_release_mac_tbl(struct opa_vnic_adapter *adapter)
134{
135	struct hlist_head *mactbl;
136
137	mutex_lock(&adapter->mactbl_lock);
138	mactbl = rcu_access_pointer(adapter->mactbl);
139	rcu_assign_pointer(adapter->mactbl, NULL);
140	synchronize_rcu();
141	opa_vnic_free_mac_tbl(mactbl);
142	adapter->info.vport.mac_tbl_digest = 0;
143	mutex_unlock(&adapter->mactbl_lock);
144}
145
146/*
147 * opa_vnic_query_mac_tbl - query the mac table for a section
148 *
149 * This function implements query of specific function of the mac table.
150 * The function also expects the requested range to be valid.
151 */
152void opa_vnic_query_mac_tbl(struct opa_vnic_adapter *adapter,
153			    struct opa_veswport_mactable *tbl)
154{
155	struct opa_vnic_mac_tbl_node *node;
156	struct hlist_head *mactbl;
157	int bkt;
158	u16 loffset, lnum_entries;
159
160	rcu_read_lock();
161	mactbl = rcu_dereference(adapter->mactbl);
162	if (!mactbl)
163		goto get_mac_done;
164
165	loffset = be16_to_cpu(tbl->offset);
166	lnum_entries = be16_to_cpu(tbl->num_entries);
167
168	vnic_hash_for_each(mactbl, bkt, node, hlist) {
169		struct __opa_vnic_mactable_entry *nentry = &node->entry;
170		struct opa_veswport_mactable_entry *entry;
171
172		if ((node->index < loffset) ||
173		    (node->index >= (loffset + lnum_entries)))
174			continue;
175
176		/* populate entry in the tbl corresponding to the index */
177		entry = &tbl->tbl_entries[node->index - loffset];
178		memcpy(entry->mac_addr, nentry->mac_addr,
179		       ARRAY_SIZE(entry->mac_addr));
180		memcpy(entry->mac_addr_mask, nentry->mac_addr_mask,
181		       ARRAY_SIZE(entry->mac_addr_mask));
182		entry->dlid_sd = cpu_to_be32(nentry->dlid_sd);
183	}
184	tbl->mac_tbl_digest = cpu_to_be32(adapter->info.vport.mac_tbl_digest);
185get_mac_done:
186	rcu_read_unlock();
187}
188
189/*
190 * opa_vnic_update_mac_tbl - update mac table section
191 *
192 * This function updates the specified section of the mac table.
193 * The procedure includes following steps.
194 *  - Allocate a new mac (hash) table.
195 *  - Add the specified entries to the new table.
196 *    (except the ones that are requested to be deleted).
197 *  - Add all the other entries from the old mac table.
198 *  - If there is a failure, free the new table and return.
199 *  - Switch to the new table.
200 *  - Free the old table and return.
201 *
202 * The function also expects the requested range to be valid.
203 */
204int opa_vnic_update_mac_tbl(struct opa_vnic_adapter *adapter,
205			    struct opa_veswport_mactable *tbl)
206{
207	struct opa_vnic_mac_tbl_node *node, *new_node;
208	struct hlist_head *new_mactbl, *old_mactbl;
209	int i, bkt, rc = 0;
210	u8 key;
211	u16 loffset, lnum_entries;
212
213	mutex_lock(&adapter->mactbl_lock);
214	/* allocate new mac table */
215	new_mactbl = opa_vnic_alloc_mac_tbl();
216	if (IS_ERR(new_mactbl)) {
217		mutex_unlock(&adapter->mactbl_lock);
218		return PTR_ERR(new_mactbl);
219	}
220
221	loffset = be16_to_cpu(tbl->offset);
222	lnum_entries = be16_to_cpu(tbl->num_entries);
223
224	/* add updated entries to the new mac table */
225	for (i = 0; i < lnum_entries; i++) {
226		struct __opa_vnic_mactable_entry *nentry;
227		struct opa_veswport_mactable_entry *entry =
228							&tbl->tbl_entries[i];
229		u8 *mac_addr = entry->mac_addr;
230		u8 empty_mac[ETH_ALEN] = { 0 };
231
232		v_dbg("new mac entry %4d: %02x:%02x:%02x:%02x:%02x:%02x %x\n",
233		      loffset + i, mac_addr[0], mac_addr[1], mac_addr[2],
234		      mac_addr[3], mac_addr[4], mac_addr[5],
235		      entry->dlid_sd);
236
237		/* if the entry is being removed, do not add it */
238		if (!memcmp(mac_addr, empty_mac, ARRAY_SIZE(empty_mac)))
239			continue;
240
241		node = kzalloc(sizeof(*node), GFP_KERNEL);
242		if (!node) {
243			rc = -ENOMEM;
244			goto updt_done;
245		}
246
247		node->index = loffset + i;
248		nentry = &node->entry;
249		memcpy(nentry->mac_addr, entry->mac_addr,
250		       ARRAY_SIZE(nentry->mac_addr));
251		memcpy(nentry->mac_addr_mask, entry->mac_addr_mask,
252		       ARRAY_SIZE(nentry->mac_addr_mask));
253		nentry->dlid_sd = be32_to_cpu(entry->dlid_sd);
254		key = node->entry.mac_addr[OPA_VNIC_MAC_HASH_IDX];
255		vnic_hash_add(new_mactbl, &node->hlist, key);
256	}
257
258	/* add other entries from current mac table to new mac table */
259	old_mactbl = rcu_access_pointer(adapter->mactbl);
260	if (!old_mactbl)
261		goto switch_tbl;
262
263	vnic_hash_for_each(old_mactbl, bkt, node, hlist) {
264		if ((node->index >= loffset) &&
265		    (node->index < (loffset + lnum_entries)))
266			continue;
267
268		new_node = kzalloc(sizeof(*new_node), GFP_KERNEL);
269		if (!new_node) {
270			rc = -ENOMEM;
271			goto updt_done;
272		}
273
274		new_node->index = node->index;
275		memcpy(&new_node->entry, &node->entry, sizeof(node->entry));
276		key = new_node->entry.mac_addr[OPA_VNIC_MAC_HASH_IDX];
277		vnic_hash_add(new_mactbl, &new_node->hlist, key);
278	}
279
280switch_tbl:
281	/* switch to new table */
282	rcu_assign_pointer(adapter->mactbl, new_mactbl);
283	synchronize_rcu();
284
285	adapter->info.vport.mac_tbl_digest = be32_to_cpu(tbl->mac_tbl_digest);
286updt_done:
287	/* upon failure, free the new table; otherwise, free the old table */
288	if (rc)
289		opa_vnic_free_mac_tbl(new_mactbl);
290	else
291		opa_vnic_free_mac_tbl(old_mactbl);
292
293	mutex_unlock(&adapter->mactbl_lock);
294	return rc;
295}
296
297/* opa_vnic_chk_mac_tbl - check mac table for dlid */
298static uint32_t opa_vnic_chk_mac_tbl(struct opa_vnic_adapter *adapter,
299				     struct ethhdr *mac_hdr)
300{
301	struct opa_vnic_mac_tbl_node *node;
302	struct hlist_head *mactbl;
303	u32 dlid = 0;
304	u8 key;
305
306	rcu_read_lock();
307	mactbl = rcu_dereference(adapter->mactbl);
308	if (unlikely(!mactbl))
309		goto chk_done;
310
311	key = mac_hdr->h_dest[OPA_VNIC_MAC_HASH_IDX];
312	vnic_hash_for_each_possible(mactbl, node, hlist, key) {
313		struct __opa_vnic_mactable_entry *entry = &node->entry;
314
315		/* if related to source mac, skip */
316		if (unlikely(OPA_VNIC_DLID_SD_IS_SRC_MAC(entry->dlid_sd)))
317			continue;
318
319		if (!memcmp(node->entry.mac_addr, mac_hdr->h_dest,
320			    ARRAY_SIZE(node->entry.mac_addr))) {
321			/* mac address found */
322			dlid = OPA_VNIC_DLID_SD_GET_DLID(node->entry.dlid_sd);
323			break;
324		}
325	}
326
327chk_done:
328	rcu_read_unlock();
329	return dlid;
330}
331
332/* opa_vnic_get_dlid - find and return the DLID */
333static uint32_t opa_vnic_get_dlid(struct opa_vnic_adapter *adapter,
334				  struct sk_buff *skb, u8 def_port)
335{
336	struct __opa_veswport_info *info = &adapter->info;
337	struct ethhdr *mac_hdr = (struct ethhdr *)skb_mac_header(skb);
338	u32 dlid;
339
340	dlid = opa_vnic_chk_mac_tbl(adapter, mac_hdr);
341	if (dlid)
342		return dlid;
343
344	if (is_multicast_ether_addr(mac_hdr->h_dest)) {
345		dlid = info->vesw.u_mcast_dlid;
346	} else {
347		if (is_local_ether_addr(mac_hdr->h_dest)) {
348			dlid = ((uint32_t)mac_hdr->h_dest[5] << 16) |
349				((uint32_t)mac_hdr->h_dest[4] << 8)  |
350				mac_hdr->h_dest[3];
351			if (unlikely(!dlid))
352				v_warn("Null dlid in MAC address\n");
353		} else if (def_port != OPA_VNIC_INVALID_PORT) {
354			if (def_port < OPA_VESW_MAX_NUM_DEF_PORT)
355				dlid = info->vesw.u_ucast_dlid[def_port];
356		}
357	}
358
359	return dlid;
360}
361
362/* opa_vnic_get_sc - return the service class */
363static u8 opa_vnic_get_sc(struct __opa_veswport_info *info,
364			  struct sk_buff *skb)
365{
366	struct ethhdr *mac_hdr = (struct ethhdr *)skb_mac_header(skb);
367	u16 vlan_tci;
368	u8 sc;
369
370	if (!__vlan_get_tag(skb, &vlan_tci)) {
371		u8 pcp = OPA_VNIC_VLAN_PCP(vlan_tci);
372
373		if (is_multicast_ether_addr(mac_hdr->h_dest))
374			sc = info->vport.pcp_to_sc_mc[pcp];
375		else
376			sc = info->vport.pcp_to_sc_uc[pcp];
377	} else {
378		if (is_multicast_ether_addr(mac_hdr->h_dest))
379			sc = info->vport.non_vlan_sc_mc;
380		else
381			sc = info->vport.non_vlan_sc_uc;
382	}
383
384	return sc;
385}
386
387u8 opa_vnic_get_vl(struct opa_vnic_adapter *adapter, struct sk_buff *skb)
388{
389	struct ethhdr *mac_hdr = (struct ethhdr *)skb_mac_header(skb);
390	struct __opa_veswport_info *info = &adapter->info;
391	u8 vl;
392
393	if (skb_vlan_tag_present(skb)) {
394		u8 pcp = skb_vlan_tag_get(skb) >> VLAN_PRIO_SHIFT;
395
396		if (is_multicast_ether_addr(mac_hdr->h_dest))
397			vl = info->vport.pcp_to_vl_mc[pcp];
398		else
399			vl = info->vport.pcp_to_vl_uc[pcp];
400	} else {
401		if (is_multicast_ether_addr(mac_hdr->h_dest))
402			vl = info->vport.non_vlan_vl_mc;
403		else
404			vl = info->vport.non_vlan_vl_uc;
405	}
406
407	return vl;
408}
409
410/* opa_vnic_get_rc - return the routing control */
411static u8 opa_vnic_get_rc(struct __opa_veswport_info *info,
412			  struct sk_buff *skb)
413{
414	u8 proto, rout_ctrl;
415
416	switch (vlan_get_protocol(skb)) {
417	case htons(ETH_P_IPV6):
418		proto = ipv6_hdr(skb)->nexthdr;
419		if (proto == IPPROTO_TCP)
420			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
421							  IPV6_TCP);
422		else if (proto == IPPROTO_UDP)
423			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
424							  IPV6_UDP);
425		else
426			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, IPV6);
427		break;
428	case htons(ETH_P_IP):
429		proto = ip_hdr(skb)->protocol;
430		if (proto == IPPROTO_TCP)
431			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
432							  IPV4_TCP);
433		else if (proto == IPPROTO_UDP)
434			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc,
435							  IPV4_UDP);
436		else
437			rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, IPV4);
438		break;
439	default:
440		rout_ctrl = OPA_VNIC_ENCAP_RC_EXT(info->vesw.rc, DEFAULT);
441	}
442
443	return rout_ctrl;
444}
445
446/* opa_vnic_calc_entropy - calculate the packet entropy */
447u8 opa_vnic_calc_entropy(struct sk_buff *skb)
448{
449	u32 hash = skb_get_hash(skb);
450
451	/* store XOR of all bytes in lower 8 bits */
452	hash ^= hash >> 8;
453	hash ^= hash >> 16;
454
455	/* return lower 8 bits as entropy */
456	return (u8)(hash & 0xFF);
457}
458
459/* opa_vnic_get_def_port - get default port based on entropy */
460static inline u8 opa_vnic_get_def_port(struct opa_vnic_adapter *adapter,
461				       u8 entropy)
462{
463	u8 flow_id;
464
465	/* Add the upper and lower 4-bits of entropy to get the flow id */
466	flow_id = ((entropy & 0xf) + (entropy >> 4));
467	return adapter->flow_tbl[flow_id & (OPA_VNIC_FLOW_TBL_SIZE - 1)];
468}
469
470/* Calculate packet length including OPA header, crc and padding */
471static inline int opa_vnic_wire_length(struct sk_buff *skb)
472{
473	u32 pad_len;
474
475	/* padding for 8 bytes size alignment */
476	pad_len = -(skb->len + OPA_VNIC_ICRC_TAIL_LEN) & 0x7;
477	pad_len += OPA_VNIC_ICRC_TAIL_LEN;
478
479	return (skb->len + pad_len) >> 3;
480}
481
482/* opa_vnic_encap_skb - encapsulate skb packet with OPA header and meta data */
483void opa_vnic_encap_skb(struct opa_vnic_adapter *adapter, struct sk_buff *skb)
484{
485	struct __opa_veswport_info *info = &adapter->info;
486	struct opa_vnic_skb_mdata *mdata;
487	u8 def_port, sc, rc, entropy, *hdr;
488	u16 len, l4_hdr;
489	u32 dlid;
490
491	hdr = skb_push(skb, OPA_VNIC_HDR_LEN);
492
493	entropy = opa_vnic_calc_entropy(skb);
494	def_port = opa_vnic_get_def_port(adapter, entropy);
495	len = opa_vnic_wire_length(skb);
496	dlid = opa_vnic_get_dlid(adapter, skb, def_port);
497	sc = opa_vnic_get_sc(info, skb);
498	rc = opa_vnic_get_rc(info, skb);
499	l4_hdr = info->vesw.vesw_id;
500
501	mdata = skb_push(skb, sizeof(*mdata));
502	mdata->vl = opa_vnic_get_vl(adapter, skb);
503	mdata->entropy = entropy;
504	mdata->flags = 0;
505	if (unlikely(!dlid)) {
506		mdata->flags = OPA_VNIC_SKB_MDATA_ENCAP_ERR;
507		return;
508	}
509
510	opa_vnic_make_header(hdr, info->vport.encap_slid, dlid, len,
511			     info->vesw.pkey, entropy, sc, rc,
512			     OPA_VNIC_L4_ETHR, l4_hdr);
513}
514