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         struct ib_mr           *global_mr;
  94         u64                     mr_page_mask;
  95         int                     mr_page_size;
  96         int                     mr_max_size;
  97         int                     max_pages_per_mr;
  98         bool                    has_fmr;
  99         bool                    has_fr;
 100         bool                    use_fmr;
 101         bool                    use_fast_reg;
 102 };
 103
 104 struct srp_host {
 105         struct srp_device      *srp_dev;
 106         u8                      port;
 107         struct device           dev;
 108         struct list_head        target_list;
 109         spinlock_t              target_lock;
 110         struct completion       released;
 111         struct list_head        list;
 112         struct mutex            add_target_mutex;
 113 };
 114
 115 struct srp_request {
 116         struct scsi_cmnd       *scmnd;
 117         struct srp_iu          *cmd;
 118         union {
 119                 struct ib_pool_fmr **fmr_list;
 120                 struct srp_fr_desc **fr_list;
 121         };
 122         u64                    *map_page;
 123         struct srp_direct_buf  *indirect_desc;
 124         dma_addr_t              indirect_dma_addr;
 125         short                   nmdesc;
 126         struct ib_cqe           reg_cqe;
 127 };
 128
 129 /**
 130  * struct srp_rdma_ch
 131  * @comp_vector: Completion vector used by this RDMA channel.
 132  */
 133 struct srp_rdma_ch {
 134         /* These are RW in the hot path, and commonly used together */
 135         struct list_head        free_tx;
 136         spinlock_t              lock;
 137         s32                     req_lim;
 138
 139         /* These are read-only in the hot path */
 140         struct srp_target_port *target ____cacheline_aligned_in_smp;
 141         struct ib_cq           *send_cq;
 142         struct ib_cq           *recv_cq;
 143         struct ib_qp           *qp;
 144         union {
 145                 struct ib_fmr_pool     *fmr_pool;
 146                 struct srp_fr_pool     *fr_pool;
 147         };
 148
 149         /* Everything above this point is used in the hot path of
 150          * command processing. Try to keep them packed into cachelines.
 151          */
 152
 153         struct completion       done;
 154         int                     status;
 155
 156         struct ib_sa_path_rec   path;
 157         struct ib_sa_query     *path_query;
 158         int                     path_query_id;
 159
 160         struct ib_cm_id        *cm_id;
 161         struct srp_iu         **tx_ring;
 162         struct srp_iu         **rx_ring;
 163         struct srp_request     *req_ring;
 164         int                     max_ti_iu_len;
 165         int                     comp_vector;
 166
 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_mr            *global_mr;
 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                     queue_size;
 206         int                     req_ring_size;
 207         int                     comp_vector;
 208         int                     tl_retry_count;
 209
 210         union ib_gid            orig_dgid;
 211         __be16                  pkey;
 212
 213         u32                     rq_tmo_jiffies;
 214
 215         int                     zero_req_lim;
 216
 217         struct work_struct      tl_err_work;
 218         struct work_struct      remove_work;
 219
 220         struct list_head        list;
 221         bool                    qp_in_error;
 222 };
 223
 224 struct srp_iu {
 225         struct list_head        list;
 226         u64                     dma;
 227         void                   *buf;
 228         size_t                  size;
 229         enum dma_data_direction direction;
 230         struct ib_cqe           cqe;
 231 };
 232
 233 /**
 234  * struct srp_fr_desc - fast registration work request arguments
 235  * @entry: Entry in srp_fr_pool.free_list.
 236  * @mr:    Memory region.
 237  * @frpl:  Fast registration page list.
 238  */
 239 struct srp_fr_desc {
 240         struct list_head                entry;
 241         struct ib_mr                    *mr;
 242 };
 243
 244 /**
 245  * struct srp_fr_pool - pool of fast registration descriptors
 246  *
 247  * An entry is available for allocation if and only if it occurs in @free_list.
 248  *
 249  * @size:      Number of descriptors in this pool.
 250  * @max_page_list_len: Maximum fast registration work request page list length.
 251  * @lock:      Protects free_list.
 252  * @free_list: List of free descriptors.
 253  * @desc:      Fast registration descriptor pool.
 254  */
 255 struct srp_fr_pool {
 256         int                     size;
 257         int                     max_page_list_len;
 258         spinlock_t              lock;
 259         struct list_head        free_list;
 260         struct srp_fr_desc      desc[0];
 261 };
 262
 263 /**
 264  * struct srp_map_state - per-request DMA memory mapping state
 265  * @desc:           Pointer to the element of the SRP buffer descriptor array
 266  *                  that is being filled in.
 267  * @pages:          Array with DMA addresses of pages being considered for
 268  *                  memory registration.
 269  * @base_dma_addr:  DMA address of the first page that has not yet been mapped.
 270  * @dma_len:        Number of bytes that will be registered with the next
 271  *                  FMR or FR memory registration call.
 272  * @total_len:      Total number of bytes in the sg-list being mapped.
 273  * @npages:         Number of page addresses in the pages[] array.
 274  * @nmdesc:         Number of FMR or FR memory descriptors used for mapping.
 275  * @ndesc:          Number of SRP buffer descriptors that have been filled in.
 276  */
 277 struct srp_map_state {
 278         union {
 279                 struct {
 280                         struct ib_pool_fmr **next;
 281                         struct ib_pool_fmr **end;
 282                 } fmr;
 283                 struct {
 284                         struct srp_fr_desc **next;
 285                         struct srp_fr_desc **end;
 286                 } fr;
 287                 struct {
 288                         void               **next;
 289                         void               **end;
 290                 } gen;
 291         };
 292         struct srp_direct_buf  *desc;
 293         union {
 294                 u64                     *pages;
 295                 struct scatterlist      *sg;
 296         };
 297         dma_addr_t              base_dma_addr;
 298         u32                     dma_len;
 299         u32                     total_len;
 300         unsigned int            npages;
 301         unsigned int            nmdesc;
 302         unsigned int            ndesc;
 303 };
 304
 305 #endif /* IB_SRP_H */