drivers/infiniband/ulp/srpt/ib_srpt.h

   1 /*
   2  * Copyright (c) 2006 - 2009 Mellanox Technology Inc.  All rights reserved.
   3  * Copyright (C) 2009 - 2010 Bart Van Assche <bvanassche@acm.org>.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  *
  33  */
  34
  35 #ifndef IB_SRPT_H
  36 #define IB_SRPT_H
  37
  38 #include <linux/types.h>
  39 #include <linux/list.h>
  40 #include <linux/wait.h>
  41
  42 #include <rdma/ib_verbs.h>
  43 #include <rdma/ib_sa.h>
  44 #include <rdma/ib_cm.h>
  45 #include <rdma/rdma_cm.h>
  46 #include <rdma/rw.h>
  47
  48 #include <scsi/srp.h>
  49
  50 #include "ib_dm_mad.h"
  51
  52 /*
  53  * The prefix the ServiceName field must start with in the device management
  54  * ServiceEntries attribute pair. See also the SRP specification.
  55  */
  56 #define SRP_SERVICE_NAME_PREFIX         "SRP.T10:"
  57
  58 struct srpt_nexus;
  59
  60 enum {
  61         /*
  62          * SRP IOControllerProfile attributes for SRP target ports that have
  63          * not been defined in <scsi/srp.h>. Source: section B.7, table B.7
  64          * in the SRP specification.
  65          */
  66         SRP_PROTOCOL = 0x0108,
  67         SRP_PROTOCOL_VERSION = 0x0001,
  68         SRP_IO_SUBCLASS = 0x609e,
  69         SRP_SEND_TO_IOC = 0x01,
  70         SRP_SEND_FROM_IOC = 0x02,
  71         SRP_RDMA_READ_FROM_IOC = 0x08,
  72         SRP_RDMA_WRITE_FROM_IOC = 0x20,
  73
  74         /*
  75          * srp_login_cmd.req_flags bitmasks. See also table 9 in the SRP
  76          * specification.
  77          */
  78         SRP_MTCH_ACTION = 0x03, /* MULTI-CHANNEL ACTION */
  79         SRP_LOSOLNT = 0x10, /* logout solicited notification */
  80         SRP_CRSOLNT = 0x20, /* credit request solicited notification */
  81         SRP_AESOLNT = 0x40, /* asynchronous event solicited notification */
  82
  83         /*
  84          * srp_cmd.sol_nt / srp_tsk_mgmt.sol_not bitmasks. See also tables
  85          * 18 and 20 in the SRP specification.
  86          */
  87         SRP_SCSOLNT = 0x02, /* SCSOLNT = successful solicited notification */
  88         SRP_UCSOLNT = 0x04, /* UCSOLNT = unsuccessful solicited notification */
  89
  90         /*
  91          * srp_rsp.sol_not / srp_t_logout.sol_not bitmasks. See also tables
  92          * 16 and 22 in the SRP specification.
  93          */
  94         SRP_SOLNT = 0x01, /* SOLNT = solicited notification */
  95
  96         /* See also table 24 in the SRP specification. */
  97         SRP_TSK_MGMT_SUCCESS = 0x00,
  98         SRP_TSK_MGMT_FUNC_NOT_SUPP = 0x04,
  99         SRP_TSK_MGMT_FAILED = 0x05,
 100
 101         /* See also table 21 in the SRP specification. */
 102         SRP_CMD_SIMPLE_Q = 0x0,
 103         SRP_CMD_HEAD_OF_Q = 0x1,
 104         SRP_CMD_ORDERED_Q = 0x2,
 105         SRP_CMD_ACA = 0x4,
 106
 107         SRP_LOGIN_RSP_MULTICHAN_NO_CHAN = 0x0,
 108         SRP_LOGIN_RSP_MULTICHAN_TERMINATED = 0x1,
 109         SRP_LOGIN_RSP_MULTICHAN_MAINTAINED = 0x2,
 110
 111         SRPT_DEF_SG_TABLESIZE = 128,
 112         /*
 113          * An experimentally determined value that avoids that QP creation
 114          * fails due to "swiotlb buffer is full" on systems using the swiotlb.
 115          */
 116         SRPT_MAX_SG_PER_WQE = 16,
 117
 118         MIN_SRPT_SQ_SIZE = 16,
 119         DEF_SRPT_SQ_SIZE = 4096,
 120         MAX_SRPT_RQ_SIZE = 128,
 121         MIN_SRPT_SRQ_SIZE = 4,
 122         DEFAULT_SRPT_SRQ_SIZE = 4095,
 123         MAX_SRPT_SRQ_SIZE = 65535,
 124         MAX_SRPT_RDMA_SIZE = 1U << 24,
 125         MAX_SRPT_RSP_SIZE = 1024,
 126
 127         MIN_MAX_REQ_SIZE = 996,
 128         DEFAULT_MAX_REQ_SIZE
 129                 = sizeof(struct srp_cmd)/*48*/
 130                 + sizeof(struct srp_indirect_buf)/*20*/
 131                 + 128 * sizeof(struct srp_direct_buf)/*16*/,
 132
 133         MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4,
 134         DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */
 135
 136         DEFAULT_MAX_RDMA_SIZE = 65536,
 137 };
 138
 139 /**
 140  * enum srpt_command_state - SCSI command state managed by SRPT
 141  * @SRPT_STATE_NEW:           New command arrived and is being processed.
 142  * @SRPT_STATE_NEED_DATA:     Processing a write or bidir command and waiting
 143  *                            for data arrival.
 144  * @SRPT_STATE_DATA_IN:       Data for the write or bidir command arrived and is
 145  *                            being processed.
 146  * @SRPT_STATE_CMD_RSP_SENT:  SRP_RSP for SRP_CMD has been sent.
 147  * @SRPT_STATE_MGMT:          Processing a SCSI task management command.
 148  * @SRPT_STATE_MGMT_RSP_SENT: SRP_RSP for SRP_TSK_MGMT has been sent.
 149  * @SRPT_STATE_DONE:          Command processing finished successfully, command
 150  *                            processing has been aborted or command processing
 151  *                            failed.
 152  */
 153 enum srpt_command_state {
 154         SRPT_STATE_NEW           = 0,
 155         SRPT_STATE_NEED_DATA     = 1,
 156         SRPT_STATE_DATA_IN       = 2,
 157         SRPT_STATE_CMD_RSP_SENT  = 3,
 158         SRPT_STATE_MGMT          = 4,
 159         SRPT_STATE_MGMT_RSP_SENT = 5,
 160         SRPT_STATE_DONE          = 6,
 161 };
 162
 163 /**
 164  * struct srpt_ioctx - shared SRPT I/O context information
 165  * @cqe:   Completion queue element.
 166  * @buf:   Pointer to the buffer.
 167  * @dma:   DMA address of the buffer.
 168  * @index: Index of the I/O context in its ioctx_ring array.
 169  */
 170 struct srpt_ioctx {
 171         struct ib_cqe           cqe;
 172         void                    *buf;
 173         dma_addr_t              dma;
 174         uint32_t                index;
 175 };
 176
 177 /**
 178  * struct srpt_recv_ioctx - SRPT receive I/O context
 179  * @ioctx:     See above.
 180  * @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list.
 181  */
 182 struct srpt_recv_ioctx {
 183         struct srpt_ioctx       ioctx;
 184         struct list_head        wait_list;
 185 };
 186
 187 struct srpt_rw_ctx {
 188         struct rdma_rw_ctx      rw;
 189         struct scatterlist      *sg;
 190         unsigned int            nents;
 191 };
 192
 193 /**
 194  * struct srpt_send_ioctx - SRPT send I/O context
 195  * @ioctx:       See above.
 196  * @ch:          Channel pointer.
 197  * @s_rw_ctx:    @rw_ctxs points here if only a single rw_ctx is needed.
 198  * @rw_ctxs:     RDMA read/write contexts.
 199  * @rdma_cqe:    RDMA completion queue element.
 200  * @free_list:   Node in srpt_rdma_ch.free_list.
 201  * @state:       I/O context state.
 202  * @cmd:         Target core command data structure.
 203  * @sense_data:  SCSI sense data.
 204  * @n_rdma:      Number of work requests needed to transfer this ioctx.
 205  * @n_rw_ctx:    Size of rw_ctxs array.
 206  * @queue_status_only: Send a SCSI status back to the initiator but no data.
 207  * @sense_data:  Sense data to be sent to the initiator.
 208  */
 209 struct srpt_send_ioctx {
 210         struct srpt_ioctx       ioctx;
 211         struct srpt_rdma_ch     *ch;
 212
 213         struct srpt_rw_ctx      s_rw_ctx;
 214         struct srpt_rw_ctx      *rw_ctxs;
 215
 216         struct ib_cqe           rdma_cqe;
 217         struct list_head        free_list;
 218         enum srpt_command_state state;
 219         struct se_cmd           cmd;
 220         u8                      n_rdma;
 221         u8                      n_rw_ctx;
 222         bool                    queue_status_only;
 223         u8                      sense_data[TRANSPORT_SENSE_BUFFER];
 224 };
 225
 226 /**
 227  * enum rdma_ch_state - SRP channel state
 228  * @CH_CONNECTING:    QP is in RTR state; waiting for RTU.
 229  * @CH_LIVE:          QP is in RTS state.
 230  * @CH_DISCONNECTING: DREQ has been sent and waiting for DREP or DREQ has
 231  *                    been received.
 232  * @CH_DRAINING:      DREP has been received or waiting for DREP timed out
 233  *                    and last work request has been queued.
 234  * @CH_DISCONNECTED:  Last completion has been received.
 235  */
 236 enum rdma_ch_state {
 237         CH_CONNECTING,
 238         CH_LIVE,
 239         CH_DISCONNECTING,
 240         CH_DRAINING,
 241         CH_DISCONNECTED,
 242 };
 243
 244 /**
 245  * struct srpt_rdma_ch - RDMA channel
 246  * @nexus:         I_T nexus this channel is associated with.
 247  * @qp:            IB queue pair used for communicating over this channel.
 248  * @cm_id:         IB CM ID associated with the channel.
 249  * @cq:            IB completion queue for this channel.
 250  * @zw_cqe:        Zero-length write CQE.
 251  * @rcu:           RCU head.
 252  * @kref:          kref for this channel.
 253  * @rq_size:       IB receive queue size.
 254  * @max_rsp_size:  Maximum size of an RSP response message in bytes.
 255  * @sq_wr_avail:   number of work requests available in the send queue.
 256  * @sport:         pointer to the information of the HCA port used by this
 257  *                 channel.
 258  * @max_ti_iu_len: maximum target-to-initiator information unit length.
 259  * @req_lim:       request limit: maximum number of requests that may be sent
 260  *                 by the initiator without having received a response.
 261  * @req_lim_delta: Number of credits not yet sent back to the initiator.
 262  * @spinlock:      Protects free_list and state.
 263  * @free_list:     Head of list with free send I/O contexts.
 264  * @state:         channel state. See also enum rdma_ch_state.
 265  * @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel.
 266  * @processing_wait_list: Whether or not cmd_wait_list is being processed.
 267  * @ioctx_ring:    Send ring.
 268  * @ioctx_recv_ring: Receive I/O context ring.
 269  * @list:          Node in srpt_nexus.ch_list.
 270  * @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This
 271  *                 list contains struct srpt_ioctx elements and is protected
 272  *                 against concurrent modification by the cm_id spinlock.
 273  * @pkey:          P_Key of the IB partition for this SRP channel.
 274  * @sess:          Session information associated with this SRP channel.
 275  * @sess_name:     Session name.
 276  * @release_work:  Allows scheduling of srpt_release_channel().
 277  */
 278 struct srpt_rdma_ch {
 279         struct srpt_nexus       *nexus;
 280         struct ib_qp            *qp;
 281         union {
 282                 struct {
 283                         struct ib_cm_id         *cm_id;
 284                 } ib_cm;
 285                 struct {
 286                         struct rdma_cm_id       *cm_id;
 287                 } rdma_cm;
 288         };
 289         struct ib_cq            *cq;
 290         struct ib_cqe           zw_cqe;
 291         struct rcu_head         rcu;
 292         struct kref             kref;
 293         int                     rq_size;
 294         u32                     max_rsp_size;
 295         atomic_t                sq_wr_avail;
 296         struct srpt_port        *sport;
 297         int                     max_ti_iu_len;
 298         atomic_t                req_lim;
 299         atomic_t                req_lim_delta;
 300         spinlock_t              spinlock;
 301         struct list_head        free_list;
 302         enum rdma_ch_state      state;
 303         struct srpt_send_ioctx  **ioctx_ring;
 304         struct srpt_recv_ioctx  **ioctx_recv_ring;
 305         struct list_head        list;
 306         struct list_head        cmd_wait_list;
 307         uint16_t                pkey;
 308         bool                    using_rdma_cm;
 309         bool                    processing_wait_list;
 310         struct se_session       *sess;
 311         u8                      sess_name[40];
 312         struct work_struct      release_work;
 313 };
 314
 315 /**
 316  * struct srpt_nexus - I_T nexus
 317  * @rcu:       RCU head for this data structure.
 318  * @entry:     srpt_port.nexus_list list node.
 319  * @ch_list:   struct srpt_rdma_ch list. Protected by srpt_port.mutex.
 320  * @i_port_id: 128-bit initiator port identifier copied from SRP_LOGIN_REQ.
 321  * @t_port_id: 128-bit target port identifier copied from SRP_LOGIN_REQ.
 322  */
 323 struct srpt_nexus {
 324         struct rcu_head         rcu;
 325         struct list_head        entry;
 326         struct list_head        ch_list;
 327         u8                      i_port_id[16];
 328         u8                      t_port_id[16];
 329 };
 330
 331 /**
 332  * struct srpt_port_attib - attributes for SRPT port
 333  * @srp_max_rdma_size: Maximum size of SRP RDMA transfers for new connections.
 334  * @srp_max_rsp_size: Maximum size of SRP response messages in bytes.
 335  * @srp_sq_size: Shared receive queue (SRQ) size.
 336  * @use_srq: Whether or not to use SRQ.
 337  */
 338 struct srpt_port_attrib {
 339         u32                     srp_max_rdma_size;
 340         u32                     srp_max_rsp_size;
 341         u32                     srp_sq_size;
 342         bool                    use_srq;
 343 };
 344
 345 /**
 346  * struct srpt_port - information associated by SRPT with a single IB port
 347  * @sdev:      backpointer to the HCA information.
 348  * @mad_agent: per-port management datagram processing information.
 349  * @enabled:   Whether or not this target port is enabled.
 350  * @port_guid: ASCII representation of Port GUID
 351  * @port_gid:  ASCII representation of Port GID
 352  * @port:      one-based port number.
 353  * @sm_lid:    cached value of the port's sm_lid.
 354  * @lid:       cached value of the port's lid.
 355  * @gid:       cached value of the port's gid.
 356  * @port_acl_lock spinlock for port_acl_list:
 357  * @work:      work structure for refreshing the aforementioned cached values.
 358  * @port_guid_tpg: TPG associated with target port GUID.
 359  * @port_guid_wwn: WWN associated with target port GUID.
 360  * @port_gid_tpg:  TPG associated with target port GID.
 361  * @port_gid_wwn:  WWN associated with target port GID.
 362  * @port_attrib:   Port attributes that can be accessed through configfs.
 363  * @ch_releaseQ:   Enables waiting for removal from nexus_list.
 364  * @mutex:         Protects nexus_list.
 365  * @nexus_list:    Nexus list. See also srpt_nexus.entry.
 366  */
 367 struct srpt_port {
 368         struct srpt_device      *sdev;
 369         struct ib_mad_agent     *mad_agent;
 370         bool                    enabled;
 371         u8                      port_guid[24];
 372         u8                      port_gid[64];
 373         u8                      port;
 374         u32                     sm_lid;
 375         u32                     lid;
 376         union ib_gid            gid;
 377         struct work_struct      work;
 378         struct se_portal_group  port_guid_tpg;
 379         struct se_wwn           port_guid_wwn;
 380         struct se_portal_group  port_gid_tpg;
 381         struct se_wwn           port_gid_wwn;
 382         struct srpt_port_attrib port_attrib;
 383         wait_queue_head_t       ch_releaseQ;
 384         struct mutex            mutex;
 385         struct list_head        nexus_list;
 386 };
 387
 388 /**
 389  * struct srpt_device - information associated by SRPT with a single HCA
 390  * @device:        Backpointer to the struct ib_device managed by the IB core.
 391  * @pd:            IB protection domain.
 392  * @lkey:          L_Key (local key) with write access to all local memory.
 393  * @srq:           Per-HCA SRQ (shared receive queue).
 394  * @cm_id:         Connection identifier.
 395  * @srq_size:      SRQ size.
 396  * @sdev_mutex:    Serializes use_srq changes.
 397  * @use_srq:       Whether or not to use SRQ.
 398  * @ioctx_ring:    Per-HCA SRQ.
 399  * @event_handler: Per-HCA asynchronous IB event handler.
 400  * @list:          Node in srpt_dev_list.
 401  * @port:          Information about the ports owned by this HCA.
 402  */
 403 struct srpt_device {
 404         struct ib_device        *device;
 405         struct ib_pd            *pd;
 406         u32                     lkey;
 407         struct ib_srq           *srq;
 408         struct ib_cm_id         *cm_id;
 409         int                     srq_size;
 410         struct mutex            sdev_mutex;
 411         bool                    use_srq;
 412         struct srpt_recv_ioctx  **ioctx_ring;
 413         struct ib_event_handler event_handler;
 414         struct list_head        list;
 415         struct srpt_port        port[];
 416 };
 417
 418 #endif                          /* IB_SRPT_H */