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_MAX_LUN             = 512,
  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         LOCAL_INV_WR_ID_MASK    = 1,
  72         FAST_REG_WR_ID_MASK     = 2,
  73 };
  74
  75 enum srp_target_state {
  76         SRP_TARGET_SCANNING,
  77         SRP_TARGET_LIVE,
  78         SRP_TARGET_REMOVED,
  79 };
  80
  81 enum srp_iu_type {
  82         SRP_IU_CMD,
  83         SRP_IU_TSK_MGMT,
  84         SRP_IU_RSP,
  85 };
  86
  87 /*
  88  * @mr_page_mask: HCA memory registration page mask.
  89  * @mr_page_size: HCA memory registration page size.
  90  * @mr_max_size: Maximum size in bytes of a single FMR / FR registration
  91  *   request.
  92  */
  93 struct srp_device {
  94         struct list_head        dev_list;
  95         struct ib_device       *dev;
  96         struct ib_pd           *pd;
  97         struct ib_mr           *mr;
  98         u64                     mr_page_mask;
  99         int                     mr_page_size;
 100         int                     mr_max_size;
 101         int                     max_pages_per_mr;
 102         bool                    has_fmr;
 103         bool                    has_fr;
 104         bool                    use_fast_reg;
 105 };
 106
 107 struct srp_host {
 108         struct srp_device      *srp_dev;
 109         u8                      port;
 110         struct device           dev;
 111         struct list_head        target_list;
 112         spinlock_t              target_lock;
 113         struct completion       released;
 114         struct list_head        list;
 115         struct mutex            add_target_mutex;
 116 };
 117
 118 struct srp_request {
 119         struct scsi_cmnd       *scmnd;
 120         struct srp_iu          *cmd;
 121         union {
 122                 struct ib_pool_fmr **fmr_list;
 123                 struct srp_fr_desc **fr_list;
 124         };
 125         u64                    *map_page;
 126         struct srp_direct_buf  *indirect_desc;
 127         dma_addr_t              indirect_dma_addr;
 128         short                   nmdesc;
 129 };
 130
 131 /**
 132  * struct srp_rdma_ch
 133  * @comp_vector: Completion vector used by this RDMA channel.
 134  */
 135 struct srp_rdma_ch {
 136         /* These are RW in the hot path, and commonly used together */
 137         struct list_head        free_tx;
 138         spinlock_t              lock;
 139         s32                     req_lim;
 140
 141         /* These are read-only in the hot path */
 142         struct srp_target_port *target ____cacheline_aligned_in_smp;
 143         struct ib_cq           *send_cq;
 144         struct ib_cq           *recv_cq;
 145         struct ib_qp           *qp;
 146         union {
 147                 struct ib_fmr_pool     *fmr_pool;
 148                 struct srp_fr_pool     *fr_pool;
 149         };
 150
 151         /* Everything above this point is used in the hot path of
 152          * command processing. Try to keep them packed into cachelines.
 153          */
 154
 155         struct completion       done;
 156         int                     status;
 157
 158         struct ib_sa_path_rec   path;
 159         struct ib_sa_query     *path_query;
 160         int                     path_query_id;
 161
 162         struct ib_cm_id        *cm_id;
 163         struct srp_iu         **tx_ring;
 164         struct srp_iu         **rx_ring;
 165         struct srp_request     *req_ring;
 166         int                     max_ti_iu_len;
 167         int                     comp_vector;
 168
 169         struct completion       tsk_mgmt_done;
 170         u8                      tsk_mgmt_status;
 171 };
 172
 173 /**
 174  * struct srp_target_port
 175  * @comp_vector: Completion vector used by the first RDMA channel created for
 176  *   this target port.
 177  */
 178 struct srp_target_port {
 179         /* read and written in the hot path */
 180         spinlock_t              lock;
 181
 182         /* read only in the hot path */
 183         struct srp_rdma_ch      *ch;
 184         u32                     ch_count;
 185         u32                     lkey;
 186         u32                     rkey;
 187         enum srp_target_state   state;
 188         unsigned int            max_iu_len;
 189         unsigned int            cmd_sg_cnt;
 190         unsigned int            indirect_size;
 191         bool                    allow_ext_sg;
 192
 193         /* other member variables */
 194         union ib_gid            sgid;
 195         __be64                  id_ext;
 196         __be64                  ioc_guid;
 197         __be64                  service_id;
 198         __be64                  initiator_ext;
 199         u16                     io_class;
 200         struct srp_host        *srp_host;
 201         struct Scsi_Host       *scsi_host;
 202         struct srp_rport       *rport;
 203         char                    target_name[32];
 204         unsigned int            scsi_id;
 205         unsigned int            sg_tablesize;
 206         int                     queue_size;
 207         int                     req_ring_size;
 208         int                     comp_vector;
 209         int                     tl_retry_count;
 210
 211         union ib_gid            orig_dgid;
 212         __be16                  pkey;
 213
 214         u32                     rq_tmo_jiffies;
 215         bool                    connected;
 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 };
 233
 234 /**
 235  * struct srp_fr_desc - fast registration work request arguments
 236  * @entry: Entry in srp_fr_pool.free_list.
 237  * @mr:    Memory region.
 238  * @frpl:  Fast registration page list.
 239  */
 240 struct srp_fr_desc {
 241         struct list_head                entry;
 242         struct ib_mr                    *mr;
 243         struct ib_fast_reg_page_list    *frpl;
 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  * @unmapped_sg:    First element of the sg-list that is mapped via FMR or FR.
 279  * @unmapped_index: Index of the first element mapped via FMR or FR.
 280  * @unmapped_addr:  DMA address of the first element mapped via FMR or FR.
 281  */
 282 struct srp_map_state {
 283         union {
 284                 struct ib_pool_fmr **next_fmr;
 285                 struct srp_fr_desc **next_fr;
 286         };
 287         struct srp_direct_buf  *desc;
 288         u64                    *pages;
 289         dma_addr_t              base_dma_addr;
 290         u32                     dma_len;
 291         u32                     total_len;
 292         unsigned int            npages;
 293         unsigned int            nmdesc;
 294         unsigned int            ndesc;
 295         struct scatterlist     *unmapped_sg;
 296         int                     unmapped_index;
 297         dma_addr_t              unmapped_addr;
 298 };
 299
 300 #endif /* IB_SRP_H */