[deliverable/linux.git] / drivers / net / mlx4 / mcg.c

/*
 * Copyright (c) 2006, 2007 Cisco Systems, Inc.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/init.h>
#include <linux/string.h>
#include <linux/slab.h>

#include <linux/mlx4/cmd.h>

#include "mlx4.h"

struct mlx4_mgm {
	__be32			next_gid_index;
	__be32			members_count;
	u32			reserved[2];
	u8			gid[16];
	__be32			qp[MLX4_QP_PER_MGM];
};

static const u8 zero_gid[16];	/* automatically initialized to 0 */

static int mlx4_READ_MCG(struct mlx4_dev *dev, int index,
			 struct mlx4_cmd_mailbox *mailbox)
{
	return mlx4_cmd_box(dev, 0, mailbox->dma, index, 0, MLX4_CMD_READ_MCG,
			    MLX4_CMD_TIME_CLASS_A);
}

static int mlx4_WRITE_MCG(struct mlx4_dev *dev, int index,
			  struct mlx4_cmd_mailbox *mailbox)
{
	return mlx4_cmd(dev, mailbox->dma, index, 0, MLX4_CMD_WRITE_MCG,
			MLX4_CMD_TIME_CLASS_A);
}

static int mlx4_MGID_HASH(struct mlx4_dev *dev, struct mlx4_cmd_mailbox *mailbox,
			  u16 *hash)
{
	u64 imm;
	int err;

	err = mlx4_cmd_imm(dev, mailbox->dma, &imm, 0, 0, MLX4_CMD_MGID_HASH,
			   MLX4_CMD_TIME_CLASS_A);

	if (!err)
		*hash = imm;

	return err;
}

/*
 * Caller must hold MCG table semaphore.  gid and mgm parameters must
 * be properly aligned for command interface.
 *
 *  Returns 0 unless a firmware command error occurs.
 *
 * If GID is found in MGM or MGM is empty, *index = *hash, *prev = -1
 * and *mgm holds MGM entry.
 *
 * if GID is found in AMGM, *index = index in AMGM, *prev = index of
 * previous entry in hash chain and *mgm holds AMGM entry.
 *
 * If no AMGM exists for given gid, *index = -1, *prev = index of last
 * entry in hash chain and *mgm holds end of hash chain.
 */
static int find_mgm(struct mlx4_dev *dev,
		    u8 *gid, struct mlx4_cmd_mailbox *mgm_mailbox,
		    u16 *hash, int *prev, int *index)
{
	struct mlx4_cmd_mailbox *mailbox;
	struct mlx4_mgm *mgm = mgm_mailbox->buf;
	u8 *mgid;
	int err;

	mailbox = mlx4_alloc_cmd_mailbox(dev);
	if (IS_ERR(mailbox))
		return -ENOMEM;
	mgid = mailbox->buf;

	memcpy(mgid, gid, 16);

	err = mlx4_MGID_HASH(dev, mailbox, hash);
	mlx4_free_cmd_mailbox(dev, mailbox);
	if (err)
		return err;

	if (0)
		mlx4_dbg(dev, "Hash for %04x:%04x:%04x:%04x:"
			  "%04x:%04x:%04x:%04x is %04x\n",
			  be16_to_cpu(((__be16 *) gid)[0]),
			  be16_to_cpu(((__be16 *) gid)[1]),
			  be16_to_cpu(((__be16 *) gid)[2]),
			  be16_to_cpu(((__be16 *) gid)[3]),
			  be16_to_cpu(((__be16 *) gid)[4]),
			  be16_to_cpu(((__be16 *) gid)[5]),
			  be16_to_cpu(((__be16 *) gid)[6]),
			  be16_to_cpu(((__be16 *) gid)[7]),
			  *hash);

	*index = *hash;
	*prev  = -1;

	do {
		err = mlx4_READ_MCG(dev, *index, mgm_mailbox);
		if (err)
			return err;

		if (!memcmp(mgm->gid, zero_gid, 16)) {
			if (*index != *hash) {
				mlx4_err(dev, "Found zero MGID in AMGM.\n");
				err = -EINVAL;
			}
			return err;
		}

		if (!memcmp(mgm->gid, gid, 16))
			return err;

		*prev = *index;
		*index = be32_to_cpu(mgm->next_gid_index) >> 6;
	} while (*index);

	*index = -1;
	return err;
}

int mlx4_multicast_attach(struct mlx4_dev *dev, struct mlx4_qp *qp, u8 gid[16])
{
	struct mlx4_priv *priv = mlx4_priv(dev);
	struct mlx4_cmd_mailbox *mailbox;
	struct mlx4_mgm *mgm;
	u32 members_count;
	u16 hash;
	int index, prev;
	int link = 0;
	int i;
	int err;

	mailbox = mlx4_alloc_cmd_mailbox(dev);
	if (IS_ERR(mailbox))
		return PTR_ERR(mailbox);
	mgm = mailbox->buf;

	mutex_lock(&priv->mcg_table.mutex);

	err = find_mgm(dev, gid, mailbox, &hash, &prev, &index);
	if (err)
		goto out;

	if (index != -1) {
		if (!memcmp(mgm->gid, zero_gid, 16))
			memcpy(mgm->gid, gid, 16);
	} else {
		link = 1;

		index = mlx4_bitmap_alloc(&priv->mcg_table.bitmap);
		if (index == -1) {
			mlx4_err(dev, "No AMGM entries left\n");
			err = -ENOMEM;
			goto out;
		}
		index += dev->caps.num_mgms;

		memset(mgm, 0, sizeof *mgm);
		memcpy(mgm->gid, gid, 16);
	}

	members_count = be32_to_cpu(mgm->members_count);
	if (members_count == MLX4_QP_PER_MGM) {
		mlx4_err(dev, "MGM at index %x is full.\n", index);
		err = -ENOMEM;
		goto out;
	}

	for (i = 0; i < members_count; ++i)
		if (mgm->qp[i] == cpu_to_be32(qp->qpn)) {
			mlx4_dbg(dev, "QP %06x already a member of MGM\n", qp->qpn);
			err = 0;
			goto out;
		}

	mgm->qp[members_count++] = cpu_to_be32(qp->qpn);
	mgm->members_count       = cpu_to_be32(members_count);

	err = mlx4_WRITE_MCG(dev, index, mailbox);
	if (err)
		goto out;

	if (!link)
		goto out;

	err = mlx4_READ_MCG(dev, prev, mailbox);
	if (err)
		goto out;

	mgm->next_gid_index = cpu_to_be32(index << 6);

	err = mlx4_WRITE_MCG(dev, prev, mailbox);
	if (err)
		goto out;

out:
	if (err && link && index != -1) {
		if (index < dev->caps.num_mgms)
			mlx4_warn(dev, "Got AMGM index %d < %d",
				  index, dev->caps.num_mgms);
		else
			mlx4_bitmap_free(&priv->mcg_table.bitmap,
					 index - dev->caps.num_mgms);
	}
	mutex_unlock(&priv->mcg_table.mutex);

	mlx4_free_cmd_mailbox(dev, mailbox);
	return err;
}
EXPORT_SYMBOL_GPL(mlx4_multicast_attach);

int mlx4_multicast_detach(struct mlx4_dev *dev, struct mlx4_qp *qp, u8 gid[16])
{
	struct mlx4_priv *priv = mlx4_priv(dev);
	struct mlx4_cmd_mailbox *mailbox;
	struct mlx4_mgm *mgm;
	u32 members_count;
	u16 hash;
	int prev, index;
	int i, loc;
	int err;

	mailbox = mlx4_alloc_cmd_mailbox(dev);
	if (IS_ERR(mailbox))
		return PTR_ERR(mailbox);
	mgm = mailbox->buf;

	mutex_lock(&priv->mcg_table.mutex);

	err = find_mgm(dev, gid, mailbox, &hash, &prev, &index);
	if (err)
		goto out;

	if (index == -1) {
		mlx4_err(dev, "MGID %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
			  "not found\n",
			  be16_to_cpu(((__be16 *) gid)[0]),
			  be16_to_cpu(((__be16 *) gid)[1]),
			  be16_to_cpu(((__be16 *) gid)[2]),
			  be16_to_cpu(((__be16 *) gid)[3]),
			  be16_to_cpu(((__be16 *) gid)[4]),
			  be16_to_cpu(((__be16 *) gid)[5]),
			  be16_to_cpu(((__be16 *) gid)[6]),
			  be16_to_cpu(((__be16 *) gid)[7]));
		err = -EINVAL;
		goto out;
	}

	members_count = be32_to_cpu(mgm->members_count);
	for (loc = -1, i = 0; i < members_count; ++i)
		if (mgm->qp[i] == cpu_to_be32(qp->qpn))
			loc = i;

	if (loc == -1) {
		mlx4_err(dev, "QP %06x not found in MGM\n", qp->qpn);
		err = -EINVAL;
		goto out;
	}


	mgm->members_count = cpu_to_be32(--members_count);
	mgm->qp[loc]       = mgm->qp[i - 1];
	mgm->qp[i - 1]     = 0;

	if (i != 1) {
		err = mlx4_WRITE_MCG(dev, index, mailbox);
		goto out;
	}

	if (prev == -1) {
		/* Remove entry from MGM */
		int amgm_index = be32_to_cpu(mgm->next_gid_index) >> 6;
		if (amgm_index) {
			err = mlx4_READ_MCG(dev, amgm_index, mailbox);
			if (err)
				goto out;
		} else
			memset(mgm->gid, 0, 16);

		err = mlx4_WRITE_MCG(dev, index, mailbox);
		if (err)
			goto out;

		if (amgm_index) {
			if (amgm_index < dev->caps.num_mgms)
				mlx4_warn(dev, "MGM entry %d had AMGM index %d < %d",
					  index, amgm_index, dev->caps.num_mgms);
			else
				mlx4_bitmap_free(&priv->mcg_table.bitmap,
						 amgm_index - dev->caps.num_mgms);
		}
	} else {
		/* Remove entry from AMGM */
		int cur_next_index = be32_to_cpu(mgm->next_gid_index) >> 6;
		err = mlx4_READ_MCG(dev, prev, mailbox);
		if (err)
			goto out;

		mgm->next_gid_index = cpu_to_be32(cur_next_index << 6);

		err = mlx4_WRITE_MCG(dev, prev, mailbox);
		if (err)
			goto out;

		if (index < dev->caps.num_mgms)
			mlx4_warn(dev, "entry %d had next AMGM index %d < %d",
				  prev, index, dev->caps.num_mgms);
		else
			mlx4_bitmap_free(&priv->mcg_table.bitmap,
					 index - dev->caps.num_mgms);
	}

out:
	mutex_unlock(&priv->mcg_table.mutex);

	mlx4_free_cmd_mailbox(dev, mailbox);
	return err;
}
EXPORT_SYMBOL_GPL(mlx4_multicast_detach);

int mlx4_init_mcg_table(struct mlx4_dev *dev)
{
	struct mlx4_priv *priv = mlx4_priv(dev);
	int err;

	err = mlx4_bitmap_init(&priv->mcg_table.bitmap,
			       dev->caps.num_amgms, dev->caps.num_amgms - 1, 0);
	if (err)
		return err;

	mutex_init(&priv->mcg_table.mutex);

	return 0;
}

void mlx4_cleanup_mcg_table(struct mlx4_dev *dev)
{
	mlx4_bitmap_cleanup(&mlx4_priv(dev)->mcg_table.bitmap);
}
Commit	Line	Data
225c7b1f RD	1	/*
	2	* Copyright (c) 2006, 2007 Cisco Systems, Inc. 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/init.h>
	34	#include <linux/string.h>
	35	#include <linux/slab.h>
	36
	37	#include <linux/mlx4/cmd.h>
	38
	39	#include "mlx4.h"
	40
	41	struct mlx4_mgm {
	42	__be32 next_gid_index;
	43	__be32 members_count;
	44	u32 reserved[2];
	45	u8 gid[16];
	46	__be32 qp[MLX4_QP_PER_MGM];
	47	};
	48
	49	static const u8 zero_gid[16]; /* automatically initialized to 0 */
	50
	51	static int mlx4_READ_MCG(struct mlx4_dev *dev, int index,
	52	struct mlx4_cmd_mailbox *mailbox)
	53	{
	54	return mlx4_cmd_box(dev, 0, mailbox->dma, index, 0, MLX4_CMD_READ_MCG,
	55	MLX4_CMD_TIME_CLASS_A);
	56	}
	57
	58	static int mlx4_WRITE_MCG(struct mlx4_dev *dev, int index,
	59	struct mlx4_cmd_mailbox *mailbox)
	60	{
	61	return mlx4_cmd(dev, mailbox->dma, index, 0, MLX4_CMD_WRITE_MCG,
	62	MLX4_CMD_TIME_CLASS_A);
	63	}
	64
65	static int mlx4_MGID_HASH(struct mlx4_dev dev, struct mlx4_cmd_mailbox mailbox,
66	u16 *hash)
67	{
68	u64 imm;
69	int err;
70
71	err = mlx4_cmd_imm(dev, mailbox->dma, &imm, 0, 0, MLX4_CMD_MGID_HASH,
72	MLX4_CMD_TIME_CLASS_A);
73
74	if (!err)
75	*hash = imm;
76
77	return err;
78	}
79
80	/*
81	* Caller must hold MCG table semaphore. gid and mgm parameters must
82	* be properly aligned for command interface.
83	*
84	* Returns 0 unless a firmware command error occurs.
85	*
86	* If GID is found in MGM or MGM is empty, index = hash, *prev = -1
87	* and *mgm holds MGM entry.
88	*
89	* if GID is found in AMGM, index = index in AMGM, prev = index of
90	* previous entry in hash chain and *mgm holds AMGM entry.
91	*
92	* If no AMGM exists for given gid, index = -1, prev = index of last
93	* entry in hash chain and *mgm holds end of hash chain.
94	*/
95	static int find_mgm(struct mlx4_dev *dev,
96	u8 gid, struct mlx4_cmd_mailbox mgm_mailbox,
97	u16 hash, int prev, int *index)
98	{
99	struct mlx4_cmd_mailbox *mailbox;
100	struct mlx4_mgm *mgm = mgm_mailbox->buf;
101	u8 *mgid;
102	int err;
103
104	mailbox = mlx4_alloc_cmd_mailbox(dev);
105	if (IS_ERR(mailbox))
106	return -ENOMEM;
107	mgid = mailbox->buf;
108
109	memcpy(mgid, gid, 16);
110
111	err = mlx4_MGID_HASH(dev, mailbox, hash);
112	mlx4_free_cmd_mailbox(dev, mailbox);
113	if (err)
114	return err;
115
116	if (0)
117	mlx4_dbg(dev, "Hash for %04x:%04x:%04x:%04x:"
118	"%04x:%04x:%04x:%04x is %04x\n",
119	be16_to_cpu(((__be16 *) gid)[0]),
120	be16_to_cpu(((__be16 *) gid)[1]),
121	be16_to_cpu(((__be16 *) gid)[2]),
122	be16_to_cpu(((__be16 *) gid)[3]),
123	be16_to_cpu(((__be16 *) gid)[4]),
124	be16_to_cpu(((__be16 *) gid)[5]),
125	be16_to_cpu(((__be16 *) gid)[6]),
126	be16_to_cpu(((__be16 *) gid)[7]),
127	*hash);
128
129	index = hash;
130	*prev = -1;
131
132	do {
133	err = mlx4_READ_MCG(dev, *index, mgm_mailbox);
134	if (err)
135	return err;
136
137	if (!memcmp(mgm->gid, zero_gid, 16)) {
138	if (index != hash) {
139	mlx4_err(dev, "Found zero MGID in AMGM.\n");
140	err = -EINVAL;
141	}
142	return err;
143	}
144
145	if (!memcmp(mgm->gid, gid, 16))
146	return err;
147
148	prev = index;
149	*index = be32_to_cpu(mgm->next_gid_index) >> 6;
150	} while (*index);
151
152	*index = -1;
153	return err;
154	}
155
156	int mlx4_multicast_attach(struct mlx4_dev dev, struct mlx4_qp qp, u8 gid[16])
157	{
158	struct mlx4_priv *priv = mlx4_priv(dev);
159	struct mlx4_cmd_mailbox *mailbox;
160	struct mlx4_mgm *mgm;
161	u32 members_count;
162	u16 hash;
163	int index, prev;
164	int link = 0;
165	int i;
166	int err;
167
168	mailbox = mlx4_alloc_cmd_mailbox(dev);
169	if (IS_ERR(mailbox))
170	return PTR_ERR(mailbox);
171	mgm = mailbox->buf;
172
173	mutex_lock(&priv->mcg_table.mutex);
174
175	err = find_mgm(dev, gid, mailbox, &hash, &prev, &index);
176	if (err)
177	goto out;
178
179	if (index != -1) {
180	if (!memcmp(mgm->gid, zero_gid, 16))
181	memcpy(mgm->gid, gid, 16);
182	} else {
183	link = 1;
184
185	index = mlx4_bitmap_alloc(&priv->mcg_table.bitmap);
186	if (index == -1) {
187	mlx4_err(dev, "No AMGM entries left\n");
188	err = -ENOMEM;
189	goto out;
190	}
191	index += dev->caps.num_mgms;
192
225c7b1f RD	193	memset(mgm, 0, sizeof *mgm);
	194	memcpy(mgm->gid, gid, 16);
	195	}
	196
	197	members_count = be32_to_cpu(mgm->members_count);
	198	if (members_count == MLX4_QP_PER_MGM) {
	199	mlx4_err(dev, "MGM at index %x is full.\n", index);
	200	err = -ENOMEM;
	201	goto out;
	202	}
	203
	204	for (i = 0; i < members_count; ++i)
	205	if (mgm->qp[i] == cpu_to_be32(qp->qpn)) {
	206	mlx4_dbg(dev, "QP %06x already a member of MGM\n", qp->qpn);
	207	err = 0;
	208	goto out;
	209	}
	210
	211	mgm->qp[members_count++] = cpu_to_be32(qp->qpn);
	212	mgm->members_count = cpu_to_be32(members_count);
	213
	214	err = mlx4_WRITE_MCG(dev, index, mailbox);
	215	if (err)
	216	goto out;
	217
	218	if (!link)
	219	goto out;
	220
	221	err = mlx4_READ_MCG(dev, prev, mailbox);
	222	if (err)
	223	goto out;
	224
	225	mgm->next_gid_index = cpu_to_be32(index << 6);
	226
	227	err = mlx4_WRITE_MCG(dev, prev, mailbox);
	228	if (err)
	229	goto out;
	230
	231	out:
	232	if (err && link && index != -1) {
	233	if (index < dev->caps.num_mgms)
	234	mlx4_warn(dev, "Got AMGM index %d < %d",
	235	index, dev->caps.num_mgms);
	236	else
	237	mlx4_bitmap_free(&priv->mcg_table.bitmap,
	238	index - dev->caps.num_mgms);
	239	}
	240	mutex_unlock(&priv->mcg_table.mutex);
	241
	242	mlx4_free_cmd_mailbox(dev, mailbox);
	243	return err;
	244	}
	245	EXPORT_SYMBOL_GPL(mlx4_multicast_attach);
	246
	247	int mlx4_multicast_detach(struct mlx4_dev dev, struct mlx4_qp qp, u8 gid[16])
	248	{
	249	struct mlx4_priv *priv = mlx4_priv(dev);
	250	struct mlx4_cmd_mailbox *mailbox;
	251	struct mlx4_mgm *mgm;
	252	u32 members_count;
	253	u16 hash;
	254	int prev, index;
	255	int i, loc;
	256	int err;
257
258	mailbox = mlx4_alloc_cmd_mailbox(dev);
259	if (IS_ERR(mailbox))
260	return PTR_ERR(mailbox);
261	mgm = mailbox->buf;
262
263	mutex_lock(&priv->mcg_table.mutex);
264
265	err = find_mgm(dev, gid, mailbox, &hash, &prev, &index);
266	if (err)
267	goto out;
268
269	if (index == -1) {
270	mlx4_err(dev, "MGID %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
271	"not found\n",
272	be16_to_cpu(((__be16 *) gid)[0]),
273	be16_to_cpu(((__be16 *) gid)[1]),
274	be16_to_cpu(((__be16 *) gid)[2]),
275	be16_to_cpu(((__be16 *) gid)[3]),
276	be16_to_cpu(((__be16 *) gid)[4]),
277	be16_to_cpu(((__be16 *) gid)[5]),
278	be16_to_cpu(((__be16 *) gid)[6]),
279	be16_to_cpu(((__be16 *) gid)[7]));
280	err = -EINVAL;
281	goto out;
282	}
283
284	members_count = be32_to_cpu(mgm->members_count);
285	for (loc = -1, i = 0; i < members_count; ++i)
286	if (mgm->qp[i] == cpu_to_be32(qp->qpn))
287	loc = i;
288
289	if (loc == -1) {
290	mlx4_err(dev, "QP %06x not found in MGM\n", qp->qpn);
291	err = -EINVAL;
292	goto out;
293	}
294
295
296	mgm->members_count = cpu_to_be32(--members_count);
297	mgm->qp[loc] = mgm->qp[i - 1];
298	mgm->qp[i - 1] = 0;
299
4dc51b32 EC	300	if (i != 1) {
4dc51b32 EC	301	err = mlx4_WRITE_MCG(dev, index, mailbox);
225c7b1f	302	goto out;
4dc51b32	303	}
225c7b1f RD	304
	305	if (prev == -1) {
	306	/* Remove entry from MGM */
	307	int amgm_index = be32_to_cpu(mgm->next_gid_index) >> 6;
	308	if (amgm_index) {
	309	err = mlx4_READ_MCG(dev, amgm_index, mailbox);
	310	if (err)
	311	goto out;
	312	} else
	313	memset(mgm->gid, 0, 16);
	314
	315	err = mlx4_WRITE_MCG(dev, index, mailbox);
	316	if (err)
	317	goto out;
	318
	319	if (amgm_index) {
	320	if (amgm_index < dev->caps.num_mgms)
	321	mlx4_warn(dev, "MGM entry %d had AMGM index %d < %d",
	322	index, amgm_index, dev->caps.num_mgms);
	323	else
	324	mlx4_bitmap_free(&priv->mcg_table.bitmap,
	325	amgm_index - dev->caps.num_mgms);
	326	}
	327	} else {
	328	/* Remove entry from AMGM */
	329	int cur_next_index = be32_to_cpu(mgm->next_gid_index) >> 6;
	330	err = mlx4_READ_MCG(dev, prev, mailbox);
	331	if (err)
	332	goto out;
	333
	334	mgm->next_gid_index = cpu_to_be32(cur_next_index << 6);
	335
	336	err = mlx4_WRITE_MCG(dev, prev, mailbox);
	337	if (err)
	338	goto out;
	339
	340	if (index < dev->caps.num_mgms)
	341	mlx4_warn(dev, "entry %d had next AMGM index %d < %d",
	342	prev, index, dev->caps.num_mgms);
	343	else
	344	mlx4_bitmap_free(&priv->mcg_table.bitmap,
	345	index - dev->caps.num_mgms);
	346	}
	347
	348	out:
	349	mutex_unlock(&priv->mcg_table.mutex);
	350
	351	mlx4_free_cmd_mailbox(dev, mailbox);
	352	return err;
	353	}
	354	EXPORT_SYMBOL_GPL(mlx4_multicast_detach);
	355
3d73c288	356	int mlx4_init_mcg_table(struct mlx4_dev *dev)
225c7b1f RD	357	{
	358	struct mlx4_priv *priv = mlx4_priv(dev);
	359	int err;
	360
	361	err = mlx4_bitmap_init(&priv->mcg_table.bitmap,
	362	dev->caps.num_amgms, dev->caps.num_amgms - 1, 0);
	363	if (err)
	364	return err;
	365
	366	mutex_init(&priv->mcg_table.mutex);
	367
	368	return 0;
	369	}
	370
	371	void mlx4_cleanup_mcg_table(struct mlx4_dev *dev)
	372	{
	373	mlx4_bitmap_cleanup(&mlx4_priv(dev)->mcg_table.bitmap);
	374	}