1/*
2 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses.  You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 *     Redistribution and use in source and binary forms, with or
11 *     without modification, are permitted provided that the following
12 *     conditions are met:
13 *
14 *      - Redistributions of source code must retain the above
15 *        copyright notice, this list of conditions and the following
16 *        disclaimer.
17 *
18 *      - Redistributions in binary form must reproduce the above
19 *        copyright notice, this list of conditions and the following
20 *        disclaimer in the documentation and/or other materials
21 *        provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33#include <linux/string.h>
34#include <linux/gfp.h>
35
36#include "mthca_dev.h"
37#include "mthca_cmd.h"
38
39struct mthca_mgm {
40	__be32 next_gid_index;
41	u32    reserved[3];
42	u8     gid[16];
43	__be32 qp[MTHCA_QP_PER_MGM];
44};
45
46static const u8 zero_gid[16];	/* automatically initialized to 0 */
47
48/*
49 * Caller must hold MCG table semaphore.  gid and mgm parameters must
50 * be properly aligned for command interface.
51 *
52 *  Returns 0 unless a firmware command error occurs.
53 *
54 * If GID is found in MGM or MGM is empty, *index = *hash, *prev = -1
55 * and *mgm holds MGM entry.
56 *
57 * if GID is found in AMGM, *index = index in AMGM, *prev = index of
58 * previous entry in hash chain and *mgm holds AMGM entry.
59 *
60 * If no AMGM exists for given gid, *index = -1, *prev = index of last
61 * entry in hash chain and *mgm holds end of hash chain.
62 */
63static int find_mgm(struct mthca_dev *dev,
64		    u8 *gid, struct mthca_mailbox *mgm_mailbox,
65		    u16 *hash, int *prev, int *index)
66{
67	struct mthca_mailbox *mailbox;
68	struct mthca_mgm *mgm = mgm_mailbox->buf;
69	u8 *mgid;
70	int err;
71
72	mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
73	if (IS_ERR(mailbox))
74		return -ENOMEM;
75	mgid = mailbox->buf;
76
77	memcpy(mgid, gid, 16);
78
79	err = mthca_MGID_HASH(dev, mailbox, hash);
80	if (err) {
81		mthca_err(dev, "MGID_HASH failed (%d)\n", err);
82		goto out;
83	}
84
85	if (0)
86		mthca_dbg(dev, "Hash for %pI6 is %04x\n", gid, *hash);
87
88	*index = *hash;
89	*prev  = -1;
90
91	do {
92		err = mthca_READ_MGM(dev, *index, mgm_mailbox);
93		if (err) {
94			mthca_err(dev, "READ_MGM failed (%d)\n", err);
95			goto out;
96		}
97
98		if (!memcmp(mgm->gid, zero_gid, 16)) {
99			if (*index != *hash) {
100				mthca_err(dev, "Found zero MGID in AMGM.\n");
101				err = -EINVAL;
102			}
103			goto out;
104		}
105
106		if (!memcmp(mgm->gid, gid, 16))
107			goto out;
108
109		*prev = *index;
110		*index = be32_to_cpu(mgm->next_gid_index) >> 6;
111	} while (*index);
112
113	*index = -1;
114
115 out:
116	mthca_free_mailbox(dev, mailbox);
117	return err;
118}
119
120int mthca_multicast_attach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
121{
122	struct mthca_dev *dev = to_mdev(ibqp->device);
123	struct mthca_mailbox *mailbox;
124	struct mthca_mgm *mgm;
125	u16 hash;
126	int index, prev;
127	int link = 0;
128	int i;
129	int err;
130
131	mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
132	if (IS_ERR(mailbox))
133		return PTR_ERR(mailbox);
134	mgm = mailbox->buf;
135
136	mutex_lock(&dev->mcg_table.mutex);
137
138	err = find_mgm(dev, gid->raw, mailbox, &hash, &prev, &index);
139	if (err)
140		goto out;
141
142	if (index != -1) {
143		if (!memcmp(mgm->gid, zero_gid, 16))
144			memcpy(mgm->gid, gid->raw, 16);
145	} else {
146		link = 1;
147
148		index = mthca_alloc(&dev->mcg_table.alloc);
149		if (index == -1) {
150			mthca_err(dev, "No AMGM entries left\n");
151			err = -ENOMEM;
152			goto out;
153		}
154
155		err = mthca_READ_MGM(dev, index, mailbox);
156		if (err) {
157			mthca_err(dev, "READ_MGM failed (%d)\n", err);
158			goto out;
159		}
160		memset(mgm, 0, sizeof *mgm);
161		memcpy(mgm->gid, gid->raw, 16);
162	}
163
164	for (i = 0; i < MTHCA_QP_PER_MGM; ++i)
165		if (mgm->qp[i] == cpu_to_be32(ibqp->qp_num | (1 << 31))) {
166			mthca_dbg(dev, "QP %06x already a member of MGM\n",
167				  ibqp->qp_num);
168			err = 0;
169			goto out;
170		} else if (!(mgm->qp[i] & cpu_to_be32(1 << 31))) {
171			mgm->qp[i] = cpu_to_be32(ibqp->qp_num | (1 << 31));
172			break;
173		}
174
175	if (i == MTHCA_QP_PER_MGM) {
176		mthca_err(dev, "MGM at index %x is full.\n", index);
177		err = -ENOMEM;
178		goto out;
179	}
180
181	err = mthca_WRITE_MGM(dev, index, mailbox);
182	if (err) {
183		mthca_err(dev, "WRITE_MGM failed %d\n", err);
184		err = -EINVAL;
185		goto out;
186	}
187
188	if (!link)
189		goto out;
190
191	err = mthca_READ_MGM(dev, prev, mailbox);
192	if (err) {
193		mthca_err(dev, "READ_MGM failed %d\n", err);
194		goto out;
195	}
196
197	mgm->next_gid_index = cpu_to_be32(index << 6);
198
199	err = mthca_WRITE_MGM(dev, prev, mailbox);
200	if (err)
201		mthca_err(dev, "WRITE_MGM returned %d\n", err);
202
203 out:
204	if (err && link && index != -1) {
205		BUG_ON(index < dev->limits.num_mgms);
206		mthca_free(&dev->mcg_table.alloc, index);
207	}
208	mutex_unlock(&dev->mcg_table.mutex);
209
210	mthca_free_mailbox(dev, mailbox);
211	return err;
212}
213
214int mthca_multicast_detach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
215{
216	struct mthca_dev *dev = to_mdev(ibqp->device);
217	struct mthca_mailbox *mailbox;
218	struct mthca_mgm *mgm;
219	u16 hash;
220	int prev, index;
221	int i, loc;
222	int err;
223
224	mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
225	if (IS_ERR(mailbox))
226		return PTR_ERR(mailbox);
227	mgm = mailbox->buf;
228
229	mutex_lock(&dev->mcg_table.mutex);
230
231	err = find_mgm(dev, gid->raw, mailbox, &hash, &prev, &index);
232	if (err)
233		goto out;
234
235	if (index == -1) {
236		mthca_err(dev, "MGID %pI6 not found\n", gid->raw);
237		err = -EINVAL;
238		goto out;
239	}
240
241	for (loc = -1, i = 0; i < MTHCA_QP_PER_MGM; ++i) {
242		if (mgm->qp[i] == cpu_to_be32(ibqp->qp_num | (1 << 31)))
243			loc = i;
244		if (!(mgm->qp[i] & cpu_to_be32(1 << 31)))
245			break;
246	}
247
248	if (loc == -1) {
249		mthca_err(dev, "QP %06x not found in MGM\n", ibqp->qp_num);
250		err = -EINVAL;
251		goto out;
252	}
253
254	mgm->qp[loc]   = mgm->qp[i - 1];
255	mgm->qp[i - 1] = 0;
256
257	err = mthca_WRITE_MGM(dev, index, mailbox);
258	if (err) {
259		mthca_err(dev, "WRITE_MGM returned %d\n", err);
260		goto out;
261	}
262
263	if (i != 1)
264		goto out;
265
266	if (prev == -1) {
267		/* Remove entry from MGM */
268		int amgm_index_to_free = be32_to_cpu(mgm->next_gid_index) >> 6;
269		if (amgm_index_to_free) {
270			err = mthca_READ_MGM(dev, amgm_index_to_free,
271					     mailbox);
272			if (err) {
273				mthca_err(dev, "READ_MGM returned %d\n", err);
274				goto out;
275			}
276		} else
277			memset(mgm->gid, 0, 16);
278
279		err = mthca_WRITE_MGM(dev, index, mailbox);
280		if (err) {
281			mthca_err(dev, "WRITE_MGM returned %d\n", err);
282			goto out;
283		}
284		if (amgm_index_to_free) {
285			BUG_ON(amgm_index_to_free < dev->limits.num_mgms);
286			mthca_free(&dev->mcg_table.alloc, amgm_index_to_free);
287		}
288	} else {
289		/* Remove entry from AMGM */
290		int curr_next_index = be32_to_cpu(mgm->next_gid_index) >> 6;
291		err = mthca_READ_MGM(dev, prev, mailbox);
292		if (err) {
293			mthca_err(dev, "READ_MGM returned %d\n", err);
294			goto out;
295		}
296
297		mgm->next_gid_index = cpu_to_be32(curr_next_index << 6);
298
299		err = mthca_WRITE_MGM(dev, prev, mailbox);
300		if (err) {
301			mthca_err(dev, "WRITE_MGM returned %d\n", err);
302			goto out;
303		}
304		BUG_ON(index < dev->limits.num_mgms);
305		mthca_free(&dev->mcg_table.alloc, index);
306	}
307
308 out:
309	mutex_unlock(&dev->mcg_table.mutex);
310
311	mthca_free_mailbox(dev, mailbox);
312	return err;
313}
314
315int mthca_init_mcg_table(struct mthca_dev *dev)
316{
317	int err;
318	int table_size = dev->limits.num_mgms + dev->limits.num_amgms;
319
320	err = mthca_alloc_init(&dev->mcg_table.alloc,
321			       table_size,
322			       table_size - 1,
323			       dev->limits.num_mgms);
324	if (err)
325		return err;
326
327	mutex_init(&dev->mcg_table.mutex);
328
329	return 0;
330}
331
332void mthca_cleanup_mcg_table(struct mthca_dev *dev)
333{
334	mthca_alloc_cleanup(&dev->mcg_table.alloc);
335}
336