drivers/infiniband/ulp/iser/iscsi_iser.h

   1 /*
   2  * iSER transport for the Open iSCSI Initiator & iSER transport internals
   3  *
   4  * Copyright (C) 2004 Dmitry Yusupov
   5  * Copyright (C) 2004 Alex Aizman
   6  * Copyright (C) 2005 Mike Christie
   7  * based on code maintained by open-iscsi@googlegroups.com
   8  *
   9  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
  10  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
  11  *
  12  * This software is available to you under a choice of one of two
  13  * licenses.  You may choose to be licensed under the terms of the GNU
  14  * General Public License (GPL) Version 2, available from the file
  15  * COPYING in the main directory of this source tree, or the
  16  * OpenIB.org BSD license below:
  17  *
  18  *     Redistribution and use in source and binary forms, with or
  19  *     without modification, are permitted provided that the following
  20  *     conditions are met:
  21  *
  22  *      - Redistributions of source code must retain the above
  23  *        copyright notice, this list of conditions and the following
  24  *        disclaimer.
  25  *
  26  *      - Redistributions in binary form must reproduce the above
  27  *        copyright notice, this list of conditions and the following
  28  *        disclaimer in the documentation and/or other materials
  29  *        provided with the distribution.
  30  *
  31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  32  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  34  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  35  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  36  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  37  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  38  * SOFTWARE.
  39  *
  40  * $Id: iscsi_iser.h 7051 2006-05-10 12:29:11Z ogerlitz $
  41  */
  42 #ifndef __ISCSI_ISER_H__
  43 #define __ISCSI_ISER_H__
  44
  45 #include <linux/types.h>
  46 #include <linux/net.h>
  47 #include <scsi/libiscsi.h>
  48 #include <scsi/scsi_transport_iscsi.h>
  49
  50 #include <linux/wait.h>
  51 #include <linux/sched.h>
  52 #include <linux/list.h>
  53 #include <linux/slab.h>
  54 #include <linux/dma-mapping.h>
  55 #include <linux/mutex.h>
  56 #include <linux/mempool.h>
  57 #include <linux/uio.h>
  58
  59 #include <linux/socket.h>
  60 #include <linux/in.h>
  61 #include <linux/in6.h>
  62
  63 #include <rdma/ib_verbs.h>
  64 #include <rdma/ib_fmr_pool.h>
  65 #include <rdma/rdma_cm.h>
  66
  67 #define DRV_NAME        "iser"
  68 #define PFX             DRV_NAME ": "
  69 #define DRV_VER         "0.1"
  70 #define DRV_DATE        "May 7th, 2006"
  71
  72 #define iser_dbg(fmt, arg...)                           \
  73         do {                                            \
  74                 if (iser_debug_level > 0)               \
  75                         printk(KERN_DEBUG PFX "%s:" fmt,\
  76                                 __func__ , ## arg);     \
  77         } while (0)
  78
  79 #define iser_err(fmt, arg...)                           \
  80         do {                                            \
  81                 printk(KERN_ERR PFX "%s:" fmt,          \
  82                        __func__ , ## arg);              \
  83         } while (0)
  84
  85 #define SHIFT_4K        12
  86 #define SIZE_4K (1UL << SHIFT_4K)
  87 #define MASK_4K (~(SIZE_4K-1))
  88
  89                                         /* support upto 512KB in one RDMA */
  90 #define ISCSI_ISER_SG_TABLESIZE         (0x80000 >> SHIFT_4K)
  91 #define ISCSI_ISER_MAX_LUN              256
  92 #define ISCSI_ISER_MAX_CMD_LEN          16
  93
  94 /* QP settings */
  95 /* Maximal bounds on received asynchronous PDUs */
  96 #define ISER_MAX_RX_MISC_PDUS           4 /* NOOP_IN(2) , ASYNC_EVENT(2)   */
  97
  98 #define ISER_MAX_TX_MISC_PDUS           6 /* NOOP_OUT(2), TEXT(1),         *
  99                                            * SCSI_TMFUNC(2), LOGOUT(1) */
 100
 101 #define ISER_QP_MAX_RECV_DTOS           (ISCSI_DEF_XMIT_CMDS_MAX + \
 102                                         ISER_MAX_RX_MISC_PDUS    +  \
 103                                         ISER_MAX_TX_MISC_PDUS)
 104
 105 /* the max TX (send) WR supported by the iSER QP is defined by                 *
 106  * max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect   *
 107  * to have at max for SCSI command. The tx posting & completion handling code  *
 108  * supports -EAGAIN scheme where tx is suspended till the QP has room for more *
 109  * send WR. D=8 comes from 64K/8K                                              */
 110
 111 #define ISER_INFLIGHT_DATAOUTS          8
 112
 113 #define ISER_QP_MAX_REQ_DTOS            (ISCSI_DEF_XMIT_CMDS_MAX *    \
 114                                         (1 + ISER_INFLIGHT_DATAOUTS) + \
 115                                         ISER_MAX_TX_MISC_PDUS        + \
 116                                         ISER_MAX_RX_MISC_PDUS)
 117
 118 #define ISER_VER                        0x10
 119 #define ISER_WSV                        0x08
 120 #define ISER_RSV                        0x04
 121
 122 struct iser_hdr {
 123         u8      flags;
 124         u8      rsvd[3];
 125         __be32  write_stag; /* write rkey */
 126         __be64  write_va;
 127         __be32  read_stag;  /* read rkey */
 128         __be64  read_va;
 129 } __attribute__((packed));
 130
 131
 132 /* Length of an object name string */
 133 #define ISER_OBJECT_NAME_SIZE               64
 134
 135 enum iser_ib_conn_state {
 136         ISER_CONN_INIT,            /* descriptor allocd, no conn          */
 137         ISER_CONN_PENDING,         /* in the process of being established */
 138         ISER_CONN_UP,              /* up and running                      */
 139         ISER_CONN_TERMINATING,     /* in the process of being terminated  */
 140         ISER_CONN_DOWN,            /* shut down                           */
 141         ISER_CONN_STATES_NUM
 142 };
 143
 144 enum iser_task_status {
 145         ISER_TASK_STATUS_INIT = 0,
 146         ISER_TASK_STATUS_STARTED,
 147         ISER_TASK_STATUS_COMPLETED
 148 };
 149
 150 enum iser_data_dir {
 151         ISER_DIR_IN = 0,           /* to initiator */
 152         ISER_DIR_OUT,              /* from initiator */
 153         ISER_DIRS_NUM
 154 };
 155
 156 struct iser_data_buf {
 157         void               *buf;      /* pointer to the sg list               */
 158         unsigned int       size;      /* num entries of this sg               */
 159         unsigned long      data_len;  /* total data len                       */
 160         unsigned int       dma_nents; /* returned by dma_map_sg               */
 161         char               *copy_buf; /* allocated copy buf for SGs unaligned *
 162                                        * for rdma which are copied            */
 163         struct scatterlist sg_single; /* SG-ified clone of a non SG SC or     *
 164                                        * unaligned SG                         */
 165   };
 166
 167 /* fwd declarations */
 168 struct iser_device;
 169 struct iscsi_iser_conn;
 170 struct iscsi_iser_cmd_task;
 171
 172 struct iser_mem_reg {
 173         u32  lkey;
 174         u32  rkey;
 175         u64  va;
 176         u64  len;
 177         void *mem_h;
 178         int  is_fmr;
 179 };
 180
 181 struct iser_regd_buf {
 182         struct iser_mem_reg     reg;        /* memory registration info        */
 183         void                    *virt_addr;
 184         struct iser_device      *device;    /* device->device for dma_unmap    */
 185         u64                     dma_addr;   /* if non zero, addr for dma_unmap */
 186         enum dma_data_direction direction;  /* direction for dma_unmap         */
 187         unsigned int            data_size;
 188         atomic_t                ref_count;  /* refcount, freed when dec to 0   */
 189 };
 190
 191 #define MAX_REGD_BUF_VECTOR_LEN 2
 192
 193 struct iser_dto {
 194         struct iscsi_iser_cmd_task *ctask;
 195         struct iser_conn *ib_conn;
 196         int                        notify_enable;
 197
 198         /* vector of registered buffers */
 199         unsigned int               regd_vector_len;
 200         struct iser_regd_buf       *regd[MAX_REGD_BUF_VECTOR_LEN];
 201
 202         /* offset into the registered buffer may be specified */
 203         unsigned int               offset[MAX_REGD_BUF_VECTOR_LEN];
 204
 205         /* a smaller size may be specified, if 0, then full size is used */
 206         unsigned int               used_sz[MAX_REGD_BUF_VECTOR_LEN];
 207 };
 208
 209 enum iser_desc_type {
 210         ISCSI_RX,
 211         ISCSI_TX_CONTROL ,
 212         ISCSI_TX_SCSI_COMMAND,
 213         ISCSI_TX_DATAOUT
 214 };
 215
 216 struct iser_desc {
 217         struct iser_hdr              iser_header;
 218         struct iscsi_hdr             iscsi_header;
 219         struct iser_regd_buf         hdr_regd_buf;
 220         void                         *data;         /* used by RX & TX_CONTROL */
 221         struct iser_regd_buf         data_regd_buf; /* used by RX & TX_CONTROL */
 222         enum   iser_desc_type        type;
 223         struct iser_dto              dto;
 224 };
 225
 226 struct iser_device {
 227         struct ib_device             *ib_device;
 228         struct ib_pd                 *pd;
 229         struct ib_cq                 *cq;
 230         struct ib_mr                 *mr;
 231         struct tasklet_struct        cq_tasklet;
 232         struct list_head             ig_list; /* entry in ig devices list */
 233         int                          refcount;
 234 };
 235
 236 struct iser_conn {
 237         struct iscsi_iser_conn       *iser_conn; /* iser conn for upcalls  */
 238         enum iser_ib_conn_state      state;         /* rdma connection state   */
 239         spinlock_t                   lock;          /* used for state changes  */
 240         struct iser_device           *device;       /* device context          */
 241         struct rdma_cm_id            *cma_id;       /* CMA ID                  */
 242         struct ib_qp                 *qp;           /* QP                      */
 243         struct ib_fmr_pool           *fmr_pool;     /* pool of IB FMRs         */
 244         int                          disc_evt_flag; /* disconn event delivered */
 245         wait_queue_head_t            wait;          /* waitq for conn/disconn  */
 246         atomic_t                     post_recv_buf_count; /* posted rx count   */
 247         atomic_t                     post_send_buf_count; /* posted tx count   */
 248         char                         name[ISER_OBJECT_NAME_SIZE];
 249         struct iser_page_vec         *page_vec;     /* represents SG to fmr maps*
 250                                                      * maps serialized as tx is*/
 251         struct list_head             conn_list;       /* entry in ig conn list */
 252 };
 253
 254 struct iscsi_iser_conn {
 255         struct iscsi_conn            *iscsi_conn;/* ptr to iscsi conn */
 256         struct iser_conn             *ib_conn;   /* iSER IB conn      */
 257
 258         rwlock_t                     lock;
 259 };
 260
 261 struct iscsi_iser_cmd_task {
 262         struct iser_desc             desc;
 263         struct iscsi_iser_conn       *iser_conn;
 264         enum iser_task_status        status;
 265         int                          command_sent;  /* set if command  sent  */
 266         int                          dir[ISER_DIRS_NUM];      /* set if dir use*/
 267         struct iser_regd_buf         rdma_regd[ISER_DIRS_NUM];/* regd rdma buf */
 268         struct iser_data_buf         data[ISER_DIRS_NUM];     /* orig. data des*/
 269         struct iser_data_buf         data_copy[ISER_DIRS_NUM];/* contig. copy  */
 270 };
 271
 272 struct iser_page_vec {
 273         u64 *pages;
 274         int length;
 275         int offset;
 276         int data_size;
 277 };
 278
 279 struct iser_global {
 280         struct mutex      device_list_mutex;/*                   */
 281         struct list_head  device_list;       /* all iSER devices */
 282         struct mutex      connlist_mutex;
 283         struct list_head  connlist;             /* all iSER IB connections */
 284
 285         struct kmem_cache *desc_cache;
 286 };
 287
 288 extern struct iser_global ig;
 289 extern int iser_debug_level;
 290
 291 /* allocate connection resources needed for rdma functionality */
 292 int iser_conn_set_full_featured_mode(struct iscsi_conn *conn);
 293
 294 int iser_send_control(struct iscsi_conn      *conn,
 295                       struct iscsi_mgmt_task *mtask);
 296
 297 int iser_send_command(struct iscsi_conn      *conn,
 298                       struct iscsi_cmd_task  *ctask);
 299
 300 int iser_send_data_out(struct iscsi_conn     *conn,
 301                        struct iscsi_cmd_task *ctask,
 302                        struct iscsi_data          *hdr);
 303
 304 void iscsi_iser_recv(struct iscsi_conn *conn,
 305                      struct iscsi_hdr       *hdr,
 306                      char                   *rx_data,
 307                      int                    rx_data_len);
 308
 309 int  iser_conn_init(struct iser_conn **ib_conn);
 310
 311 void iser_conn_terminate(struct iser_conn *ib_conn);
 312
 313 void iser_rcv_completion(struct iser_desc *desc,
 314                          unsigned long    dto_xfer_len);
 315
 316 void iser_snd_completion(struct iser_desc *desc);
 317
 318 void iser_ctask_rdma_init(struct iscsi_iser_cmd_task     *ctask);
 319
 320 void iser_ctask_rdma_finalize(struct iscsi_iser_cmd_task *ctask);
 321
 322 void iser_dto_buffs_release(struct iser_dto *dto);
 323
 324 int  iser_regd_buff_release(struct iser_regd_buf *regd_buf);
 325
 326 void iser_reg_single(struct iser_device      *device,
 327                      struct iser_regd_buf    *regd_buf,
 328                      enum dma_data_direction direction);
 329
 330 void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_cmd_task *ctask,
 331                                      enum iser_data_dir         cmd_dir);
 332
 333 int  iser_reg_rdma_mem(struct iscsi_iser_cmd_task *ctask,
 334                        enum   iser_data_dir        cmd_dir);
 335
 336 int  iser_connect(struct iser_conn   *ib_conn,
 337                   struct sockaddr_in *src_addr,
 338                   struct sockaddr_in *dst_addr,
 339                   int                non_blocking);
 340
 341 int  iser_reg_page_vec(struct iser_conn     *ib_conn,
 342                        struct iser_page_vec *page_vec,
 343                        struct iser_mem_reg  *mem_reg);
 344
 345 void iser_unreg_mem(struct iser_mem_reg *mem_reg);
 346
 347 int  iser_post_recv(struct iser_desc *rx_desc);
 348 int  iser_post_send(struct iser_desc *tx_desc);
 349
 350 int iser_conn_state_comp(struct iser_conn *ib_conn,
 351                          enum iser_ib_conn_state comp);
 352
 353 int iser_dma_map_task_data(struct iscsi_iser_cmd_task *iser_ctask,
 354                             struct iser_data_buf       *data,
 355                             enum   iser_data_dir       iser_dir,
 356                             enum   dma_data_direction  dma_dir);
 357
 358 void iser_dma_unmap_task_data(struct iscsi_iser_cmd_task *iser_ctask);
 359 #endif