drivers/infiniband/ulp/srp/ib_srp.h

   1 /*
   2  * Copyright (c) 2005 Cisco Systems.  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 #ifndef IB_SRP_H
  34 #define IB_SRP_H
  35
  36 #include <linux/types.h>
  37 #include <linux/list.h>
  38 #include <linux/mutex.h>
  39 #include <linux/scatterlist.h>
  40
  41 #include <scsi/scsi_host.h>
  42 #include <scsi/scsi_cmnd.h>
  43
  44 #include <rdma/ib_verbs.h>
  45 #include <rdma/ib_sa.h>
  46 #include <rdma/ib_cm.h>
  47 #include <rdma/ib_fmr_pool.h>
  48 #include <rdma/rdma_cm.h>
  49
  50 enum {
  51         SRP_PATH_REC_TIMEOUT_MS = 1000,
  52         SRP_ABORT_TIMEOUT_MS    = 5000,
  53
  54         SRP_PORT_REDIRECT       = 1,
  55         SRP_DLID_REDIRECT       = 2,
  56         SRP_STALE_CONN          = 3,
  57
  58         SRP_DEF_SG_TABLESIZE    = 12,
  59
  60         SRP_DEFAULT_QUEUE_SIZE  = 1 << 6,
  61         SRP_RSP_SQ_SIZE         = 1,
  62         SRP_TSK_MGMT_SQ_SIZE    = 1,
  63         SRP_DEFAULT_CMD_SQ_SIZE = SRP_DEFAULT_QUEUE_SIZE - SRP_RSP_SQ_SIZE -
  64                                   SRP_TSK_MGMT_SQ_SIZE,
  65
  66         SRP_TAG_NO_REQ          = ~0U,
  67         SRP_TAG_TSK_MGMT        = 1U << 31,
  68
  69         SRP_MAX_PAGES_PER_MR    = 512,
  70 };
  71
  72 enum srp_target_state {
  73         SRP_TARGET_SCANNING,
  74         SRP_TARGET_LIVE,
  75         SRP_TARGET_REMOVED,
  76 };
  77
  78 enum srp_iu_type {
  79         SRP_IU_CMD,
  80         SRP_IU_TSK_MGMT,
  81         SRP_IU_RSP,
  82 };
  83
  84 /*
  85  * @mr_page_mask: HCA memory registration page mask.
  86  * @mr_page_size: HCA memory registration page size.
  87  * @mr_max_size: Maximum size in bytes of a single FMR / FR registration
  88  *   request.
  89  */
  90 struct srp_device {
  91         struct list_head        dev_list;
  92         struct ib_device       *dev;
  93         struct ib_pd           *pd;
  94         u32                     global_rkey;
  95         u64                     mr_page_mask;
  96         int                     mr_page_size;
  97         int                     mr_max_size;
  98         int                     max_pages_per_mr;
  99         bool                    has_fmr;
 100         bool                    has_fr;
 101         bool                    use_fmr;
 102         bool                    use_fast_reg;
 103 };
 104
 105 struct srp_host {
 106         struct srp_device      *srp_dev;
 107         u8                      port;
 108         struct device           dev;
 109         struct list_head        target_list;
 110         spinlock_t              target_lock;
 111         struct completion       released;
 112         struct list_head        list;
 113         struct mutex            add_target_mutex;
 114 };
 115
 116 struct srp_request {
 117         struct scsi_cmnd       *scmnd;
 118         struct srp_iu          *cmd;
 119         union {
 120                 struct ib_pool_fmr **fmr_list;
 121                 struct srp_fr_desc **fr_list;
 122         };
 123         u64                    *map_page;
 124         struct srp_direct_buf  *indirect_desc;
 125         dma_addr_t              indirect_dma_addr;
 126         short                   nmdesc;
 127         struct ib_cqe           reg_cqe;
 128 };
 129
 130 /**
 131  * struct srp_rdma_ch
 132  * @comp_vector: Completion vector used by this RDMA channel.
 133  */
 134 struct srp_rdma_ch {
 135         /* These are RW in the hot path, and commonly used together */
 136         struct list_head        free_tx;
 137         spinlock_t              lock;
 138         s32                     req_lim;
 139
 140         /* These are read-only in the hot path */
 141         struct srp_target_port *target ____cacheline_aligned_in_smp;
 142         struct ib_cq           *send_cq;
 143         struct ib_cq           *recv_cq;
 144         struct ib_qp           *qp;
 145         union {
 146                 struct ib_fmr_pool     *fmr_pool;
 147                 struct srp_fr_pool     *fr_pool;
 148         };
 149
 150         /* Everything above this point is used in the hot path of
 151          * command processing. Try to keep them packed into cachelines.
 152          */
 153
 154         struct completion       done;
 155         int                     status;
 156
 157         union {
 158                 struct ib_cm {
 159                         struct sa_path_rec      path;
 160                         struct ib_sa_query      *path_query;
 161                         int                     path_query_id;
 162                         struct ib_cm_id         *cm_id;
 163                 } ib_cm;
 164                 struct rdma_cm {
 165                         struct rdma_cm_id       *cm_id;
 166                 } rdma_cm;
 167         };
 168
 169         struct srp_iu         **tx_ring;
 170         struct srp_iu         **rx_ring;
 171         struct srp_request     *req_ring;
 172         int                     max_ti_iu_len;
 173         int                     comp_vector;
 174
 175         u64                     tsk_mgmt_tag;
 176         struct completion       tsk_mgmt_done;
 177         u8                      tsk_mgmt_status;
 178         bool                    connected;
 179 };
 180
 181 /**
 182  * struct srp_target_port
 183  * @comp_vector: Completion vector used by the first RDMA channel created for
 184  *   this target port.
 185  */
 186 struct srp_target_port {
 187         /* read and written in the hot path */
 188         spinlock_t              lock;
 189
 190         /* read only in the hot path */
 191         u32                     global_rkey;
 192         struct srp_rdma_ch      *ch;
 193         struct net              *net;
 194         u32                     ch_count;
 195         u32                     lkey;
 196         enum srp_target_state   state;
 197         unsigned int            max_iu_len;
 198         unsigned int            cmd_sg_cnt;
 199         unsigned int            indirect_size;
 200         bool                    allow_ext_sg;
 201
 202         /* other member variables */
 203         union ib_gid            sgid;
 204         __be64                  id_ext;
 205         __be64                  ioc_guid;
 206         __be64                  initiator_ext;
 207         u16                     io_class;
 208         struct srp_host        *srp_host;
 209         struct Scsi_Host       *scsi_host;
 210         struct srp_rport       *rport;
 211         char                    target_name[32];
 212         unsigned int            scsi_id;
 213         unsigned int            sg_tablesize;
 214         unsigned int            target_can_queue;
 215         int                     mr_pool_size;
 216         int                     mr_per_cmd;
 217         int                     queue_size;
 218         int                     req_ring_size;
 219         int                     comp_vector;
 220         int                     tl_retry_count;
 221
 222         bool                    using_rdma_cm;
 223
 224         union {
 225                 struct {
 226                         __be64                  service_id;
 227                         union ib_gid            orig_dgid;
 228                         __be16                  pkey;
 229                 } ib_cm;
 230                 struct {
 231                         union {
 232                                 struct sockaddr_in      ip4;
 233                                 struct sockaddr_in6     ip6;
 234                                 struct sockaddr_storage ss;
 235                         } src;
 236                         union {
 237                                 struct sockaddr_in      ip4;
 238                                 struct sockaddr_in6     ip6;
 239                                 struct sockaddr_storage ss;
 240                         } dst;
 241                         bool src_specified;
 242                 } rdma_cm;
 243         };
 244
 245         u32                     rq_tmo_jiffies;
 246
 247         int                     zero_req_lim;
 248
 249         struct work_struct      tl_err_work;
 250         struct work_struct      remove_work;
 251
 252         struct list_head        list;
 253         bool                    qp_in_error;
 254 };
 255
 256 struct srp_iu {
 257         struct list_head        list;
 258         u64                     dma;
 259         void                   *buf;
 260         size_t                  size;
 261         enum dma_data_direction direction;
 262         struct ib_cqe           cqe;
 263 };
 264
 265 /**
 266  * struct srp_fr_desc - fast registration work request arguments
 267  * @entry: Entry in srp_fr_pool.free_list.
 268  * @mr:    Memory region.
 269  * @frpl:  Fast registration page list.
 270  */
 271 struct srp_fr_desc {
 272         struct list_head                entry;
 273         struct ib_mr                    *mr;
 274 };
 275
 276 /**
 277  * struct srp_fr_pool - pool of fast registration descriptors
 278  *
 279  * An entry is available for allocation if and only if it occurs in @free_list.
 280  *
 281  * @size:      Number of descriptors in this pool.
 282  * @max_page_list_len: Maximum fast registration work request page list length.
 283  * @lock:      Protects free_list.
 284  * @free_list: List of free descriptors.
 285  * @desc:      Fast registration descriptor pool.
 286  */
 287 struct srp_fr_pool {
 288         int                     size;
 289         int                     max_page_list_len;
 290         spinlock_t              lock;
 291         struct list_head        free_list;
 292         struct srp_fr_desc      desc[0];
 293 };
 294
 295 /**
 296  * struct srp_map_state - per-request DMA memory mapping state
 297  * @desc:           Pointer to the element of the SRP buffer descriptor array
 298  *                  that is being filled in.
 299  * @pages:          Array with DMA addresses of pages being considered for
 300  *                  memory registration.
 301  * @base_dma_addr:  DMA address of the first page that has not yet been mapped.
 302  * @dma_len:        Number of bytes that will be registered with the next
 303  *                  FMR or FR memory registration call.
 304  * @total_len:      Total number of bytes in the sg-list being mapped.
 305  * @npages:         Number of page addresses in the pages[] array.
 306  * @nmdesc:         Number of FMR or FR memory descriptors used for mapping.
 307  * @ndesc:          Number of SRP buffer descriptors that have been filled in.
 308  */
 309 struct srp_map_state {
 310         union {
 311                 struct {
 312                         struct ib_pool_fmr **next;
 313                         struct ib_pool_fmr **end;
 314                 } fmr;
 315                 struct {
 316                         struct srp_fr_desc **next;
 317                         struct srp_fr_desc **end;
 318                 } fr;
 319                 struct {
 320                         void               **next;
 321                         void               **end;
 322                 } gen;
 323         };
 324         struct srp_direct_buf  *desc;
 325         union {
 326                 u64                     *pages;
 327                 struct scatterlist      *sg;
 328         };
 329         dma_addr_t              base_dma_addr;
 330         u32                     dma_len;
 331         u32                     total_len;
 332         unsigned int            npages;
 333         unsigned int            nmdesc;
 334         unsigned int            ndesc;
 335 };
 336
 337 #endif /* IB_SRP_H */