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