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/init.h>
  35 #include <linux/string.h>
  36 #include <linux/slab.h>
  37
  38 #include <linux/mlx4/cmd.h>
  39
  40 #include "mlx4.h"
  41
  42 #define MGM_QPN_MASK       0x00FFFFFF
  43 #define MGM_BLCK_LB_BIT    30
  44
  45 struct mlx4_mgm {
  46         __be32                  next_gid_index;
  47         __be32                  members_count;
  48         u32                     reserved[2];
  49         u8                      gid[16];
  50         __be32                  qp[MLX4_QP_PER_MGM];
  51 };
  52
  53 static const u8 zero_gid[16];   /* automatically initialized to 0 */
  54
  55 static int mlx4_READ_MCG(struct mlx4_dev *dev, int index,
  56                          struct mlx4_cmd_mailbox *mailbox)
  57 {
  58         return mlx4_cmd_box(dev, 0, mailbox->dma, index, 0, MLX4_CMD_READ_MCG,
  59                             MLX4_CMD_TIME_CLASS_A);
  60 }
  61
  62 static int mlx4_WRITE_MCG(struct mlx4_dev *dev, int index,
  63                           struct mlx4_cmd_mailbox *mailbox)
  64 {
  65         return mlx4_cmd(dev, mailbox->dma, index, 0, MLX4_CMD_WRITE_MCG,
  66                         MLX4_CMD_TIME_CLASS_A);
  67 }
  68
  69 static int mlx4_MGID_HASH(struct mlx4_dev *dev, struct mlx4_cmd_mailbox *mailbox,
  70                           u16 *hash)
  71 {
  72         u64 imm;
  73         int err;
  74
  75         err = mlx4_cmd_imm(dev, mailbox->dma, &imm, 0, 0, MLX4_CMD_MGID_HASH,
  76                            MLX4_CMD_TIME_CLASS_A);
  77
  78         if (!err)
  79                 *hash = imm;
  80
  81         return err;
  82 }
  83
  84 /*
  85  * Caller must hold MCG table semaphore.  gid and mgm parameters must
  86  * be properly aligned for command interface.
  87  *
  88  *  Returns 0 unless a firmware command error occurs.
  89  *
  90  * If GID is found in MGM or MGM is empty, *index = *hash, *prev = -1
  91  * and *mgm holds MGM entry.
  92  *
  93  * if GID is found in AMGM, *index = index in AMGM, *prev = index of
  94  * previous entry in hash chain and *mgm holds AMGM entry.
  95  *
  96  * If no AMGM exists for given gid, *index = -1, *prev = index of last
  97  * entry in hash chain and *mgm holds end of hash chain.
  98  */
  99 static int find_mgm(struct mlx4_dev *dev,
 100                     u8 *gid, struct mlx4_cmd_mailbox *mgm_mailbox,
 101                     u16 *hash, int *prev, int *index)
 102 {
 103         struct mlx4_cmd_mailbox *mailbox;
 104         struct mlx4_mgm *mgm = mgm_mailbox->buf;
 105         u8 *mgid;
 106         int err;
 107
 108         mailbox = mlx4_alloc_cmd_mailbox(dev);
 109         if (IS_ERR(mailbox))
 110                 return -ENOMEM;
 111         mgid = mailbox->buf;
 112
 113         memcpy(mgid, gid, 16);
 114
 115         err = mlx4_MGID_HASH(dev, mailbox, hash);
 116         mlx4_free_cmd_mailbox(dev, mailbox);
 117         if (err)
 118                 return err;
 119
 120         if (0)
 121                 mlx4_dbg(dev, "Hash for %pI6 is %04x\n", gid, *hash);
 122
 123         *index = *hash;
 124         *prev  = -1;
 125
 126         do {
 127                 err = mlx4_READ_MCG(dev, *index, mgm_mailbox);
 128                 if (err)
 129                         return err;
 130
 131                 if (!memcmp(mgm->gid, zero_gid, 16)) {
 132                         if (*index != *hash) {
 133                                 mlx4_err(dev, "Found zero MGID in AMGM.\n");
 134                                 err = -EINVAL;
 135                         }
 136                         return err;
 137                 }
 138
 139                 if (!memcmp(mgm->gid, gid, 16))
 140                         return err;
 141
 142                 *prev = *index;
 143                 *index = be32_to_cpu(mgm->next_gid_index) >> 6;
 144         } while (*index);
 145
 146         *index = -1;
 147         return err;
 148 }
 149
 150 int mlx4_multicast_attach(struct mlx4_dev *dev, struct mlx4_qp *qp, u8 gid[16],
 151                           int block_mcast_loopback)
 152 {
 153         struct mlx4_priv *priv = mlx4_priv(dev);
 154         struct mlx4_cmd_mailbox *mailbox;
 155         struct mlx4_mgm *mgm;
 156         u32 members_count;
 157         u16 hash;
 158         int index, prev;
 159         int link = 0;
 160         int i;
 161         int err;
 162
 163         mailbox = mlx4_alloc_cmd_mailbox(dev);
 164         if (IS_ERR(mailbox))
 165                 return PTR_ERR(mailbox);
 166         mgm = mailbox->buf;
 167
 168         mutex_lock(&priv->mcg_table.mutex);
 169
 170         err = find_mgm(dev, gid, mailbox, &hash, &prev, &index);
 171         if (err)
 172                 goto out;
 173
 174         if (index != -1) {
 175                 if (!memcmp(mgm->gid, zero_gid, 16))
 176                         memcpy(mgm->gid, gid, 16);
 177         } else {
 178                 link = 1;
 179
 180                 index = mlx4_bitmap_alloc(&priv->mcg_table.bitmap);
 181                 if (index == -1) {
 182                         mlx4_err(dev, "No AMGM entries left\n");
 183                         err = -ENOMEM;
 184                         goto out;
 185                 }
 186                 index += dev->caps.num_mgms;
 187
 188                 memset(mgm, 0, sizeof *mgm);
 189                 memcpy(mgm->gid, gid, 16);
 190         }
 191
 192         members_count = be32_to_cpu(mgm->members_count);
 193         if (members_count == MLX4_QP_PER_MGM) {
 194                 mlx4_err(dev, "MGM at index %x is full.\n", index);
 195                 err = -ENOMEM;
 196                 goto out;
 197         }
 198
 199         for (i = 0; i < members_count; ++i)
 200                 if ((be32_to_cpu(mgm->qp[i]) & MGM_QPN_MASK) == qp->qpn) {
 201                         mlx4_dbg(dev, "QP %06x already a member of MGM\n", qp->qpn);
 202                         err = 0;
 203                         goto out;
 204                 }
 205
 206         if (block_mcast_loopback)
 207                 mgm->qp[members_count++] = cpu_to_be32((qp->qpn & MGM_QPN_MASK) |
 208                                                        (1U << MGM_BLCK_LB_BIT));
 209         else
 210                 mgm->qp[members_count++] = cpu_to_be32(qp->qpn & MGM_QPN_MASK);
 211
 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 %pI6 not found\n", gid);
 271                 err = -EINVAL;
 272                 goto out;
 273         }
 274
 275         members_count = be32_to_cpu(mgm->members_count);
 276         for (loc = -1, i = 0; i < members_count; ++i)
 277                 if ((be32_to_cpu(mgm->qp[i]) & MGM_QPN_MASK) == qp->qpn)
 278                         loc = i;
 279
 280         if (loc == -1) {
 281                 mlx4_err(dev, "QP %06x not found in MGM\n", qp->qpn);
 282                 err = -EINVAL;
 283                 goto out;
 284         }
 285
 286
 287         mgm->members_count = cpu_to_be32(--members_count);
 288         mgm->qp[loc]       = mgm->qp[i - 1];
 289         mgm->qp[i - 1]     = 0;
 290
 291         if (i != 1) {
 292                 err = mlx4_WRITE_MCG(dev, index, mailbox);
 293                 goto out;
 294         }
 295
 296         if (prev == -1) {
 297                 /* Remove entry from MGM */
 298                 int amgm_index = be32_to_cpu(mgm->next_gid_index) >> 6;
 299                 if (amgm_index) {
 300                         err = mlx4_READ_MCG(dev, amgm_index, mailbox);
 301                         if (err)
 302                                 goto out;
 303                 } else
 304                         memset(mgm->gid, 0, 16);
 305
 306                 err = mlx4_WRITE_MCG(dev, index, mailbox);
 307                 if (err)
 308                         goto out;
 309
 310                 if (amgm_index) {
 311                         if (amgm_index < dev->caps.num_mgms)
 312                                 mlx4_warn(dev, "MGM entry %d had AMGM index %d < %d",
 313                                           index, amgm_index, dev->caps.num_mgms);
 314                         else
 315                                 mlx4_bitmap_free(&priv->mcg_table.bitmap,
 316                                                  amgm_index - dev->caps.num_mgms);
 317                 }
 318         } else {
 319                 /* Remove entry from AMGM */
 320                 int cur_next_index = be32_to_cpu(mgm->next_gid_index) >> 6;
 321                 err = mlx4_READ_MCG(dev, prev, mailbox);
 322                 if (err)
 323                         goto out;
 324
 325                 mgm->next_gid_index = cpu_to_be32(cur_next_index << 6);
 326
 327                 err = mlx4_WRITE_MCG(dev, prev, mailbox);
 328                 if (err)
 329                         goto out;
 330
 331                 if (index < dev->caps.num_mgms)
 332                         mlx4_warn(dev, "entry %d had next AMGM index %d < %d",
 333                                   prev, index, dev->caps.num_mgms);
 334                 else
 335                         mlx4_bitmap_free(&priv->mcg_table.bitmap,
 336                                          index - dev->caps.num_mgms);
 337         }
 338
 339 out:
 340         mutex_unlock(&priv->mcg_table.mutex);
 341
 342         mlx4_free_cmd_mailbox(dev, mailbox);
 343         return err;
 344 }
 345 EXPORT_SYMBOL_GPL(mlx4_multicast_detach);
 346
 347 int mlx4_init_mcg_table(struct mlx4_dev *dev)
 348 {
 349         struct mlx4_priv *priv = mlx4_priv(dev);
 350         int err;
 351
 352         err = mlx4_bitmap_init(&priv->mcg_table.bitmap, dev->caps.num_amgms,
 353                                dev->caps.num_amgms - 1, 0, 0);
 354         if (err)
 355                 return err;
 356
 357         mutex_init(&priv->mcg_table.mutex);
 358
 359         return 0;
 360 }
 361
 362 void mlx4_cleanup_mcg_table(struct mlx4_dev *dev)
 363 {
 364         mlx4_bitmap_cleanup(&mlx4_priv(dev)->mcg_table.bitmap);
 365 }