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_LIVE,
  77         SRP_TARGET_REMOVED,
  78 };
  79
  80 enum srp_iu_type {
  81         SRP_IU_CMD,
  82         SRP_IU_TSK_MGMT,
  83         SRP_IU_RSP,
  84 };
  85
  86 /*
  87  * @mr_page_mask: HCA memory registration page mask.
  88  * @mr_page_size: HCA memory registration page size.
  89  * @mr_max_size: Maximum size in bytes of a single FMR / FR registration
  90  *   request.
  91  */
  92 struct srp_device {
  93         struct list_head        dev_list;
  94         struct ib_device       *dev;
  95         struct ib_pd           *pd;
  96         struct ib_mr           *mr;
  97         u64                     mr_page_mask;
  98         int                     mr_page_size;
  99         int                     mr_max_size;
 100         int                     max_pages_per_mr;
 101         bool                    has_fmr;
 102         bool                    has_fr;
 103         bool                    use_fast_reg;
 104 };
 105
 106 struct srp_host {
 107         struct srp_device      *srp_dev;
 108         u8                      port;
 109         struct device           dev;
 110         struct list_head        target_list;
 111         spinlock_t              target_lock;
 112         struct completion       released;
 113         struct list_head        list;
 114         struct mutex            add_target_mutex;
 115 };
 116
 117 struct srp_request {
 118         struct list_head        list;
 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         short                   index;
 130 };
 131
 132 struct srp_target_port {
 133         /* These are RW in the hot path, and commonly used together */
 134         struct list_head        free_tx;
 135         struct list_head        free_reqs;
 136         spinlock_t              lock;
 137         s32                     req_lim;
 138
 139         /* These are read-only in the hot path */
 140         struct ib_cq           *send_cq ____cacheline_aligned_in_smp;
 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         u32                     lkey;
 148         u32                     rkey;
 149         enum srp_target_state   state;
 150         unsigned int            max_iu_len;
 151         unsigned int            cmd_sg_cnt;
 152         unsigned int            indirect_size;
 153         bool                    allow_ext_sg;
 154
 155         /* Everything above this point is used in the hot path of
 156          * command processing. Try to keep them packed into cachelines.
 157          */
 158
 159         __be64                  id_ext;
 160         __be64                  ioc_guid;
 161         __be64                  service_id;
 162         __be64                  initiator_ext;
 163         u16                     io_class;
 164         struct srp_host        *srp_host;
 165         struct Scsi_Host       *scsi_host;
 166         struct srp_rport       *rport;
 167         char                    target_name[32];
 168         unsigned int            scsi_id;
 169         unsigned int            sg_tablesize;
 170         int                     queue_size;
 171         int                     req_ring_size;
 172         int                     comp_vector;
 173         int                     tl_retry_count;
 174
 175         struct ib_sa_path_rec   path;
 176         __be16                  orig_dgid[8];
 177         struct ib_sa_query     *path_query;
 178         int                     path_query_id;
 179
 180         u32                     rq_tmo_jiffies;
 181         bool                    connected;
 182
 183         struct ib_cm_id        *cm_id;
 184
 185         int                     max_ti_iu_len;
 186
 187         int                     zero_req_lim;
 188
 189         struct srp_iu          **tx_ring;
 190         struct srp_iu          **rx_ring;
 191         struct srp_request      *req_ring;
 192
 193         struct work_struct      tl_err_work;
 194         struct work_struct      remove_work;
 195
 196         struct list_head        list;
 197         struct completion       done;
 198         int                     status;
 199         bool                    qp_in_error;
 200
 201         struct completion       tsk_mgmt_done;
 202         u8                      tsk_mgmt_status;
 203 };
 204
 205 struct srp_iu {
 206         struct list_head        list;
 207         u64                     dma;
 208         void                   *buf;
 209         size_t                  size;
 210         enum dma_data_direction direction;
 211 };
 212
 213 /**
 214  * struct srp_fr_desc - fast registration work request arguments
 215  * @entry: Entry in srp_fr_pool.free_list.
 216  * @mr:    Memory region.
 217  * @frpl:  Fast registration page list.
 218  */
 219 struct srp_fr_desc {
 220         struct list_head                entry;
 221         struct ib_mr                    *mr;
 222         struct ib_fast_reg_page_list    *frpl;
 223 };
 224
 225 /**
 226  * struct srp_fr_pool - pool of fast registration descriptors
 227  *
 228  * An entry is available for allocation if and only if it occurs in @free_list.
 229  *
 230  * @size:      Number of descriptors in this pool.
 231  * @max_page_list_len: Maximum fast registration work request page list length.
 232  * @lock:      Protects free_list.
 233  * @free_list: List of free descriptors.
 234  * @desc:      Fast registration descriptor pool.
 235  */
 236 struct srp_fr_pool {
 237         int                     size;
 238         int                     max_page_list_len;
 239         spinlock_t              lock;
 240         struct list_head        free_list;
 241         struct srp_fr_desc      desc[0];
 242 };
 243
 244 /**
 245  * struct srp_map_state - per-request DMA memory mapping state
 246  * @desc:           Pointer to the element of the SRP buffer descriptor array
 247  *                  that is being filled in.
 248  * @pages:          Array with DMA addresses of pages being considered for
 249  *                  memory registration.
 250  * @base_dma_addr:  DMA address of the first page that has not yet been mapped.
 251  * @dma_len:        Number of bytes that will be registered with the next
 252  *                  FMR or FR memory registration call.
 253  * @total_len:      Total number of bytes in the sg-list being mapped.
 254  * @npages:         Number of page addresses in the pages[] array.
 255  * @nmdesc:         Number of FMR or FR memory descriptors used for mapping.
 256  * @ndesc:          Number of SRP buffer descriptors that have been filled in.
 257  * @unmapped_sg:    First element of the sg-list that is mapped via FMR or FR.
 258  * @unmapped_index: Index of the first element mapped via FMR or FR.
 259  * @unmapped_addr:  DMA address of the first element mapped via FMR or FR.
 260  */
 261 struct srp_map_state {
 262         union {
 263                 struct ib_pool_fmr **next_fmr;
 264                 struct srp_fr_desc **next_fr;
 265         };
 266         struct srp_direct_buf  *desc;
 267         u64                    *pages;
 268         dma_addr_t              base_dma_addr;
 269         u32                     dma_len;
 270         u32                     total_len;
 271         unsigned int            npages;
 272         unsigned int            nmdesc;
 273         unsigned int            ndesc;
 274         struct scatterlist     *unmapped_sg;
 275         int                     unmapped_index;
 276         dma_addr_t              unmapped_addr;
 277 };
 278
 279 #endif /* IB_SRP_H */