drivers/net/mlx4/mcg.c

   1 /*
   2  * Copyright (c) 2006, 2007 Cisco Systems, Inc.  All rights reserved.
   3  * Copyright (c) 2007, 2008 Mellanox Technologies. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/string.h>
  35 #include <linux/slab.h>
  36
  37 #include <linux/mlx4/cmd.h>
  38
  39 #include "mlx4.h"
  40
  41 #define MGM_QPN_MASK       0x00FFFFFF
  42 #define MGM_BLCK_LB_BIT    30
  43
  44 struct mlx4_mgm {
  45         __be32                  next_gid_index;
  46         __be32                  members_count;
  47         u32                     reserved[2];
  48         u8                      gid[16];
  49         __be32                  qp[MLX4_QP_PER_MGM];
  50 };
  51
  52 static const u8 zero_gid[16];   /* automatically initialized to 0 */
  53
  54 static int mlx4_READ_MCG(struct mlx4_dev *dev, int index,
  55                          struct mlx4_cmd_mailbox *mailbox)
  56 {
  57         return mlx4_cmd_box(dev, 0, mailbox->dma, index, 0, MLX4_CMD_READ_MCG,
  58                             MLX4_CMD_TIME_CLASS_A);
  59 }
  60
  61 static int mlx4_WRITE_MCG(struct mlx4_dev *dev, int index,
  62                           struct mlx4_cmd_mailbox *mailbox)
  63 {
  64         return mlx4_cmd(dev, mailbox->dma, index, 0, MLX4_CMD_WRITE_MCG,
  65                         MLX4_CMD_TIME_CLASS_A);
  66 }
  67
  68 static int mlx4_MGID_HASH(struct mlx4_dev *dev, struct mlx4_cmd_mailbox *mailbox,
  69                           u16 *hash)
  70 {
  71         u64 imm;
  72         int err;
  73
  74         err = mlx4_cmd_imm(dev, mailbox->dma, &imm, 0, 0, MLX4_CMD_MGID_HASH,
  75                            MLX4_CMD_TIME_CLASS_A);
  76
  77         if (!err)
  78                 *hash = imm;
  79
  80         return err;
  81 }
  82
  83 /*
  84  * Caller must hold MCG table semaphore.  gid and mgm parameters must
  85  * be properly aligned for command interface.
  86  *
  87  *  Returns 0 unless a firmware command error occurs.
  88  *
  89  * If GID is found in MGM or MGM is empty, *index = *hash, *prev = -1
  90  * and *mgm holds MGM entry.
  91  *
  92  * if GID is found in AMGM, *index = index in AMGM, *prev = index of
  93  * previous entry in hash chain and *mgm holds AMGM entry.
  94  *
  95  * If no AMGM exists for given gid, *index = -1, *prev = index of last
  96  * entry in hash chain and *mgm holds end of hash chain.
  97  */
  98 static int find_mgm(struct mlx4_dev *dev,
  99                     u8 *gid, struct mlx4_cmd_mailbox *mgm_mailbox,
 100                     u16 *hash, int *prev, int *index)
 101 {
 102         struct mlx4_cmd_mailbox *mailbox;
 103         struct mlx4_mgm *mgm = mgm_mailbox->buf;
 104         u8 *mgid;
 105         int err;
 106
 107         mailbox = mlx4_alloc_cmd_mailbox(dev);
 108         if (IS_ERR(mailbox))
 109                 return -ENOMEM;
 110         mgid = mailbox->buf;
 111
 112         memcpy(mgid, gid, 16);
 113
 114         err = mlx4_MGID_HASH(dev, mailbox, hash);
 115         mlx4_free_cmd_mailbox(dev, mailbox);
 116         if (err)
 117                 return err;
 118
 119         if (0)
 120                 mlx4_dbg(dev, "Hash for %pI6 is %04x\n", gid, *hash);
 121
 122         *index = *hash;
 123         *prev  = -1;
 124
 125         do {
 126                 err = mlx4_READ_MCG(dev, *index, mgm_mailbox);
 127                 if (err)
 128                         return err;
 129
 130                 if (!memcmp(mgm->gid, zero_gid, 16)) {
 131                         if (*index != *hash) {
 132                                 mlx4_err(dev, "Found zero MGID in AMGM.\n");
 133                                 err = -EINVAL;
 134                         }
 135                         return err;
 136                 }
 137
 138                 if (!memcmp(mgm->gid, gid, 16))
 139                         return err;
 140
 141                 *prev = *index;
 142                 *index = be32_to_cpu(mgm->next_gid_index) >> 6;
 143         } while (*index);
 144
 145         *index = -1;
 146         return err;
 147 }
 148
 149 int mlx4_multicast_attach(struct mlx4_dev *dev, struct mlx4_qp *qp, u8 gid[16],
 150                           int block_mcast_loopback)
 151 {
 152         struct mlx4_priv *priv = mlx4_priv(dev);
 153         struct mlx4_cmd_mailbox *mailbox;
 154         struct mlx4_mgm *mgm;
 155         u32 members_count;
 156         u16 hash;
 157         int index, prev;
 158         int link = 0;
 159         int i;
 160         int err;
 161
 162         mailbox = mlx4_alloc_cmd_mailbox(dev);
 163         if (IS_ERR(mailbox))
 164                 return PTR_ERR(mailbox);
 165         mgm = mailbox->buf;
 166
 167         mutex_lock(&priv->mcg_table.mutex);
 168
 169         err = find_mgm(dev, gid, mailbox, &hash, &prev, &index);
 170         if (err)
 171                 goto out;
 172
 173         if (index != -1) {
 174                 if (!memcmp(mgm->gid, zero_gid, 16))
 175                         memcpy(mgm->gid, gid, 16);
 176         } else {
 177                 link = 1;
 178
 179                 index = mlx4_bitmap_alloc(&priv->mcg_table.bitmap);
 180                 if (index == -1) {
 181                         mlx4_err(dev, "No AMGM entries left\n");
 182                         err = -ENOMEM;
 183                         goto out;
 184                 }
 185                 index += dev->caps.num_mgms;
 186
 187                 memset(mgm, 0, sizeof *mgm);
 188                 memcpy(mgm->gid, gid, 16);
 189         }
 190
 191         members_count = be32_to_cpu(mgm->members_count);
 192         if (members_count == MLX4_QP_PER_MGM) {
 193                 mlx4_err(dev, "MGM at index %x is full.\n", index);
 194                 err = -ENOMEM;
 195                 goto out;
 196         }
 197
 198         for (i = 0; i < members_count; ++i)
 199                 if ((be32_to_cpu(mgm->qp[i]) & MGM_QPN_MASK) == qp->qpn) {
 200                         mlx4_dbg(dev, "QP %06x already a member of MGM\n", qp->qpn);
 201                         err = 0;
 202                         goto out;
 203                 }
 204
 205         if (block_mcast_loopback)
 206                 mgm->qp[members_count++] = cpu_to_be32((qp->qpn & MGM_QPN_MASK) |
 207                                                        (1U << MGM_BLCK_LB_BIT));
 208         else
 209                 mgm->qp[members_count++] = cpu_to_be32(qp->qpn & MGM_QPN_MASK);
 210
 211         mgm->members_count       = cpu_to_be32(members_count);
 212
 213         err = mlx4_WRITE_MCG(dev, index, mailbox);
 214         if (err)
 215                 goto out;
 216
 217         if (!link)
 218                 goto out;
 219
 220         err = mlx4_READ_MCG(dev, prev, mailbox);
 221         if (err)
 222                 goto out;
 223
 224         mgm->next_gid_index = cpu_to_be32(index << 6);
 225
 226         err = mlx4_WRITE_MCG(dev, prev, mailbox);
 227         if (err)
 228                 goto out;
 229
 230 out:
 231         if (err && link && index != -1) {
 232                 if (index < dev->caps.num_mgms)
 233                         mlx4_warn(dev, "Got AMGM index %d < %d",
 234                                   index, dev->caps.num_mgms);
 235                 else
 236                         mlx4_bitmap_free(&priv->mcg_table.bitmap,
 237                                          index - dev->caps.num_mgms);
 238         }
 239         mutex_unlock(&priv->mcg_table.mutex);
 240
 241         mlx4_free_cmd_mailbox(dev, mailbox);
 242         return err;
 243 }
 244 EXPORT_SYMBOL_GPL(mlx4_multicast_attach);
 245
 246 int mlx4_multicast_detach(struct mlx4_dev *dev, struct mlx4_qp *qp, u8 gid[16])
 247 {
 248         struct mlx4_priv *priv = mlx4_priv(dev);
 249         struct mlx4_cmd_mailbox *mailbox;
 250         struct mlx4_mgm *mgm;
 251         u32 members_count;
 252         u16 hash;
 253         int prev, index;
 254         int i, loc;
 255         int err;
 256
 257         mailbox = mlx4_alloc_cmd_mailbox(dev);
 258         if (IS_ERR(mailbox))
 259                 return PTR_ERR(mailbox);
 260         mgm = mailbox->buf;
 261
 262         mutex_lock(&priv->mcg_table.mutex);
 263
 264         err = find_mgm(dev, gid, mailbox, &hash, &prev, &index);
 265         if (err)
 266                 goto out;
 267
 268         if (index == -1) {
 269                 mlx4_err(dev, "MGID %pI6 not found\n", gid);
 270                 err = -EINVAL;
 271                 goto out;
 272         }
 273
 274         members_count = be32_to_cpu(mgm->members_count);
 275         for (loc = -1, i = 0; i < members_count; ++i)
 276                 if ((be32_to_cpu(mgm->qp[i]) & MGM_QPN_MASK) == qp->qpn)
 277                         loc = i;
 278
 279         if (loc == -1) {
 280                 mlx4_err(dev, "QP %06x not found in MGM\n", qp->qpn);
 281                 err = -EINVAL;
 282                 goto out;
 283         }
 284
 285
 286         mgm->members_count = cpu_to_be32(--members_count);
 287         mgm->qp[loc]       = mgm->qp[i - 1];
 288         mgm->qp[i - 1]     = 0;
 289
 290         if (i != 1) {
 291                 err = mlx4_WRITE_MCG(dev, index, mailbox);
 292                 goto out;
 293         }
 294
 295         if (prev == -1) {
 296                 /* Remove entry from MGM */
 297                 int amgm_index = be32_to_cpu(mgm->next_gid_index) >> 6;
 298                 if (amgm_index) {
 299                         err = mlx4_READ_MCG(dev, amgm_index, mailbox);
 300                         if (err)
 301                                 goto out;
 302                 } else
 303                         memset(mgm->gid, 0, 16);
 304
 305                 err = mlx4_WRITE_MCG(dev, index, mailbox);
 306                 if (err)
 307                         goto out;
 308
 309                 if (amgm_index) {
 310                         if (amgm_index < dev->caps.num_mgms)
 311                                 mlx4_warn(dev, "MGM entry %d had AMGM index %d < %d",
 312                                           index, amgm_index, dev->caps.num_mgms);
 313                         else
 314                                 mlx4_bitmap_free(&priv->mcg_table.bitmap,
 315                                                  amgm_index - dev->caps.num_mgms);
 316                 }
 317         } else {
 318                 /* Remove entry from AMGM */
 319                 int cur_next_index = be32_to_cpu(mgm->next_gid_index) >> 6;
 320                 err = mlx4_READ_MCG(dev, prev, mailbox);
 321                 if (err)
 322                         goto out;
 323
 324                 mgm->next_gid_index = cpu_to_be32(cur_next_index << 6);
 325
 326                 err = mlx4_WRITE_MCG(dev, prev, mailbox);
 327                 if (err)
 328                         goto out;
 329
 330                 if (index < dev->caps.num_mgms)
 331                         mlx4_warn(dev, "entry %d had next AMGM index %d < %d",
 332                                   prev, index, dev->caps.num_mgms);
 333                 else
 334                         mlx4_bitmap_free(&priv->mcg_table.bitmap,
 335                                          index - dev->caps.num_mgms);
 336         }
 337
 338 out:
 339         mutex_unlock(&priv->mcg_table.mutex);
 340
 341         mlx4_free_cmd_mailbox(dev, mailbox);
 342         return err;
 343 }
 344 EXPORT_SYMBOL_GPL(mlx4_multicast_detach);
 345
 346 int mlx4_init_mcg_table(struct mlx4_dev *dev)
 347 {
 348         struct mlx4_priv *priv = mlx4_priv(dev);
 349         int err;
 350
 351         err = mlx4_bitmap_init(&priv->mcg_table.bitmap, dev->caps.num_amgms,
 352                                dev->caps.num_amgms - 1, 0, 0);
 353         if (err)
 354                 return err;
 355
 356         mutex_init(&priv->mcg_table.mutex);
 357
 358         return 0;
 359 }
 360
 361 void mlx4_cleanup_mcg_table(struct mlx4_dev *dev)
 362 {
 363         mlx4_bitmap_cleanup(&mlx4_priv(dev)->mcg_table.bitmap);
 364 }