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 #ifndef __ISCSI_ISER_H__
  41 #define __ISCSI_ISER_H__
  42
  43 #include <linux/types.h>
  44 #include <linux/net.h>
  45 #include <scsi/libiscsi.h>
  46 #include <scsi/scsi_transport_iscsi.h>
  47
  48 #include <linux/interrupt.h>
  49 #include <linux/wait.h>
  50 #include <linux/sched.h>
  51 #include <linux/list.h>
  52 #include <linux/slab.h>
  53 #include <linux/dma-mapping.h>
  54 #include <linux/mutex.h>
  55 #include <linux/mempool.h>
  56 #include <linux/uio.h>
  57
  58 #include <linux/socket.h>
  59 #include <linux/in.h>
  60 #include <linux/in6.h>
  61
  62 #include <rdma/ib_verbs.h>
  63 #include <rdma/ib_fmr_pool.h>
  64 #include <rdma/rdma_cm.h>
  65
  66 #define DRV_NAME        "iser"
  67 #define PFX             DRV_NAME ": "
  68 #define DRV_VER         "0.1"
  69 #define DRV_DATE        "May 7th, 2006"
  70
  71 #define iser_dbg(fmt, arg...)                           \
  72         do {                                            \
  73                 if (iser_debug_level > 1)               \
  74                         printk(KERN_DEBUG PFX "%s:" fmt,\
  75                                 __func__ , ## arg);     \
  76         } while (0)
  77
  78 #define iser_warn(fmt, arg...)                          \
  79         do {                                            \
  80                 if (iser_debug_level > 0)               \
  81                         printk(KERN_DEBUG PFX "%s:" fmt,\
  82                                 __func__ , ## arg);     \
  83         } while (0)
  84
  85 #define iser_err(fmt, arg...)                           \
  86         do {                                            \
  87                 printk(KERN_ERR PFX "%s:" fmt,          \
  88                        __func__ , ## arg);              \
  89         } while (0)
  90
  91 #define SHIFT_4K        12
  92 #define SIZE_4K (1ULL << SHIFT_4K)
  93 #define MASK_4K (~(SIZE_4K-1))
  94
  95                                         /* support up to 512KB in one RDMA */
  96 #define ISCSI_ISER_SG_TABLESIZE         (0x80000 >> SHIFT_4K)
  97 #define ISER_DEF_CMD_PER_LUN            128
  98
  99 /* QP settings */
 100 /* Maximal bounds on received asynchronous PDUs */
 101 #define ISER_MAX_RX_MISC_PDUS           4 /* NOOP_IN(2) , ASYNC_EVENT(2)   */
 102
 103 #define ISER_MAX_TX_MISC_PDUS           6 /* NOOP_OUT(2), TEXT(1),         *
 104                                            * SCSI_TMFUNC(2), LOGOUT(1) */
 105
 106 #define ISER_QP_MAX_RECV_DTOS           (ISCSI_DEF_XMIT_CMDS_MAX)
 107
 108 #define ISER_MIN_POSTED_RX              (ISCSI_DEF_XMIT_CMDS_MAX >> 2)
 109
 110 /* the max TX (send) WR supported by the iSER QP is defined by                 *
 111  * max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect   *
 112  * to have at max for SCSI command. The tx posting & completion handling code  *
 113  * supports -EAGAIN scheme where tx is suspended till the QP has room for more *
 114  * send WR. D=8 comes from 64K/8K                                              */
 115
 116 #define ISER_INFLIGHT_DATAOUTS          8
 117
 118 #define ISER_QP_MAX_REQ_DTOS            (ISCSI_DEF_XMIT_CMDS_MAX *    \
 119                                         (1 + ISER_INFLIGHT_DATAOUTS) + \
 120                                         ISER_MAX_TX_MISC_PDUS        + \
 121                                         ISER_MAX_RX_MISC_PDUS)
 122
 123 #define ISER_VER                        0x10
 124 #define ISER_WSV                        0x08
 125 #define ISER_RSV                        0x04
 126
 127 struct iser_hdr {
 128         u8      flags;
 129         u8      rsvd[3];
 130         __be32  write_stag; /* write rkey */
 131         __be64  write_va;
 132         __be32  read_stag;  /* read rkey */
 133         __be64  read_va;
 134 } __attribute__((packed));
 135
 136 /* Constant PDU lengths calculations */
 137 #define ISER_HEADERS_LEN  (sizeof(struct iser_hdr) + sizeof(struct iscsi_hdr))
 138
 139 #define ISER_RECV_DATA_SEG_LEN  128
 140 #define ISER_RX_PAYLOAD_SIZE    (ISER_HEADERS_LEN + ISER_RECV_DATA_SEG_LEN)
 141 #define ISER_RX_LOGIN_SIZE      (ISER_HEADERS_LEN + ISCSI_DEF_MAX_RECV_SEG_LEN)
 142
 143 /* Length of an object name string */
 144 #define ISER_OBJECT_NAME_SIZE               64
 145
 146 enum iser_ib_conn_state {
 147         ISER_CONN_INIT,            /* descriptor allocd, no conn          */
 148         ISER_CONN_PENDING,         /* in the process of being established */
 149         ISER_CONN_UP,              /* up and running                      */
 150         ISER_CONN_TERMINATING,     /* in the process of being terminated  */
 151         ISER_CONN_DOWN,            /* shut down                           */
 152         ISER_CONN_STATES_NUM
 153 };
 154
 155 enum iser_task_status {
 156         ISER_TASK_STATUS_INIT = 0,
 157         ISER_TASK_STATUS_STARTED,
 158         ISER_TASK_STATUS_COMPLETED
 159 };
 160
 161 enum iser_data_dir {
 162         ISER_DIR_IN = 0,           /* to initiator */
 163         ISER_DIR_OUT,              /* from initiator */
 164         ISER_DIRS_NUM
 165 };
 166
 167 struct iser_data_buf {
 168         void               *buf;      /* pointer to the sg list               */
 169         unsigned int       size;      /* num entries of this sg               */
 170         unsigned long      data_len;  /* total data len                       */
 171         unsigned int       dma_nents; /* returned by dma_map_sg               */
 172         char               *copy_buf; /* allocated copy buf for SGs unaligned *
 173                                        * for rdma which are copied            */
 174         struct scatterlist sg_single; /* SG-ified clone of a non SG SC or     *
 175                                        * unaligned SG                         */
 176   };
 177
 178 /* fwd declarations */
 179 struct iser_device;
 180 struct iscsi_iser_conn;
 181 struct iscsi_iser_task;
 182 struct iscsi_endpoint;
 183
 184 struct iser_mem_reg {
 185         u32  lkey;
 186         u32  rkey;
 187         u64  va;
 188         u64  len;
 189         void *mem_h;
 190         int  is_fmr;
 191 };
 192
 193 struct iser_regd_buf {
 194         struct iser_mem_reg     reg;        /* memory registration info        */
 195         void                    *virt_addr;
 196         struct iser_device      *device;    /* device->device for dma_unmap    */
 197         enum dma_data_direction direction;  /* direction for dma_unmap         */
 198         unsigned int            data_size;
 199 };
 200
 201 enum iser_desc_type {
 202         ISCSI_TX_CONTROL ,
 203         ISCSI_TX_SCSI_COMMAND,
 204         ISCSI_TX_DATAOUT
 205 };
 206
 207 struct iser_tx_desc {
 208         struct iser_hdr              iser_header;
 209         struct iscsi_hdr             iscsi_header;
 210         enum   iser_desc_type        type;
 211         u64                          dma_addr;
 212         /* sg[0] points to iser/iscsi headers, sg[1] optionally points to either
 213         of immediate data, unsolicited data-out or control (login,text) */
 214         struct ib_sge                tx_sg[2];
 215         int                          num_sge;
 216 };
 217
 218 #define ISER_RX_PAD_SIZE        (256 - (ISER_RX_PAYLOAD_SIZE + \
 219                                         sizeof(u64) + sizeof(struct ib_sge)))
 220 struct iser_rx_desc {
 221         struct iser_hdr              iser_header;
 222         struct iscsi_hdr             iscsi_header;
 223         char                         data[ISER_RECV_DATA_SEG_LEN];
 224         u64                          dma_addr;
 225         struct ib_sge                rx_sg;
 226         char                         pad[ISER_RX_PAD_SIZE];
 227 } __attribute__((packed));
 228
 229 struct iser_device {
 230         struct ib_device             *ib_device;
 231         struct ib_pd                 *pd;
 232         struct ib_cq                 *rx_cq;
 233         struct ib_cq                 *tx_cq;
 234         struct ib_mr                 *mr;
 235         struct tasklet_struct        cq_tasklet;
 236         struct ib_event_handler      event_handler;
 237         struct list_head             ig_list; /* entry in ig devices list */
 238         int                          refcount;
 239 };
 240
 241 struct iser_conn {
 242         struct iscsi_iser_conn       *iser_conn; /* iser conn for upcalls  */
 243         struct iscsi_endpoint        *ep;
 244         enum iser_ib_conn_state      state;         /* rdma connection state   */
 245         atomic_t                     refcount;
 246         spinlock_t                   lock;          /* used for state changes  */
 247         struct iser_device           *device;       /* device context          */
 248         struct rdma_cm_id            *cma_id;       /* CMA ID                  */
 249         struct ib_qp                 *qp;           /* QP                      */
 250         struct ib_fmr_pool           *fmr_pool;     /* pool of IB FMRs         */
 251         wait_queue_head_t            wait;          /* waitq for conn/disconn  */
 252         int                          post_recv_buf_count; /* posted rx count  */
 253         atomic_t                     post_send_buf_count; /* posted tx count   */
 254         char                         name[ISER_OBJECT_NAME_SIZE];
 255         struct iser_page_vec         *page_vec;     /* represents SG to fmr maps*
 256                                                      * maps serialized as tx is*/
 257         struct list_head             conn_list;       /* entry in ig conn list */
 258
 259         char                         *login_buf;
 260         u64                          login_dma;
 261         unsigned int                 rx_desc_head;
 262         struct iser_rx_desc          *rx_descs;
 263         struct ib_recv_wr            rx_wr[ISER_MIN_POSTED_RX];
 264 };
 265
 266 struct iscsi_iser_conn {
 267         struct iscsi_conn            *iscsi_conn;/* ptr to iscsi conn */
 268         struct iser_conn             *ib_conn;   /* iSER IB conn      */
 269 };
 270
 271 struct iscsi_iser_task {
 272         struct iser_tx_desc          desc;
 273         struct iscsi_iser_conn       *iser_conn;
 274         enum iser_task_status        status;
 275         int                          command_sent;  /* set if command  sent  */
 276         int                          dir[ISER_DIRS_NUM];      /* set if dir use*/
 277         struct iser_regd_buf         rdma_regd[ISER_DIRS_NUM];/* regd rdma buf */
 278         struct iser_data_buf         data[ISER_DIRS_NUM];     /* orig. data des*/
 279         struct iser_data_buf         data_copy[ISER_DIRS_NUM];/* contig. copy  */
 280         int                          headers_initialized;
 281 };
 282
 283 struct iser_page_vec {
 284         u64 *pages;
 285         int length;
 286         int offset;
 287         int data_size;
 288 };
 289
 290 struct iser_global {
 291         struct mutex      device_list_mutex;/*                   */
 292         struct list_head  device_list;       /* all iSER devices */
 293         struct mutex      connlist_mutex;
 294         struct list_head  connlist;             /* all iSER IB connections */
 295
 296         struct kmem_cache *desc_cache;
 297 };
 298
 299 extern struct iser_global ig;
 300 extern int iser_debug_level;
 301
 302 /* allocate connection resources needed for rdma functionality */
 303 int iser_conn_set_full_featured_mode(struct iscsi_conn *conn);
 304
 305 int iser_send_control(struct iscsi_conn *conn,
 306                       struct iscsi_task *task);
 307
 308 int iser_send_command(struct iscsi_conn *conn,
 309                       struct iscsi_task *task);
 310
 311 int iser_send_data_out(struct iscsi_conn *conn,
 312                        struct iscsi_task *task,
 313                        struct iscsi_data *hdr);
 314
 315 void iscsi_iser_recv(struct iscsi_conn *conn,
 316                      struct iscsi_hdr       *hdr,
 317                      char                   *rx_data,
 318                      int                    rx_data_len);
 319
 320 void iser_conn_init(struct iser_conn *ib_conn);
 321
 322 void iser_conn_get(struct iser_conn *ib_conn);
 323
 324 int iser_conn_put(struct iser_conn *ib_conn, int destroy_cma_id_allowed);
 325
 326 void iser_conn_terminate(struct iser_conn *ib_conn);
 327
 328 void iser_rcv_completion(struct iser_rx_desc *desc,
 329                          unsigned long    dto_xfer_len,
 330                         struct iser_conn *ib_conn);
 331
 332 void iser_snd_completion(struct iser_tx_desc *desc, struct iser_conn *ib_conn);
 333
 334 void iser_task_rdma_init(struct iscsi_iser_task *task);
 335
 336 void iser_task_rdma_finalize(struct iscsi_iser_task *task);
 337
 338 void iser_free_rx_descriptors(struct iser_conn *ib_conn);
 339
 340 void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_task *task,
 341                                      enum iser_data_dir         cmd_dir);
 342
 343 int  iser_reg_rdma_mem(struct iscsi_iser_task *task,
 344                        enum   iser_data_dir        cmd_dir);
 345
 346 int  iser_connect(struct iser_conn   *ib_conn,
 347                   struct sockaddr_in *src_addr,
 348                   struct sockaddr_in *dst_addr,
 349                   int                non_blocking);
 350
 351 int  iser_reg_page_vec(struct iser_conn     *ib_conn,
 352                        struct iser_page_vec *page_vec,
 353                        struct iser_mem_reg  *mem_reg);
 354
 355 void iser_unreg_mem(struct iser_mem_reg *mem_reg);
 356
 357 int  iser_post_recvl(struct iser_conn *ib_conn);
 358 int  iser_post_recvm(struct iser_conn *ib_conn, int count);
 359 int  iser_post_send(struct iser_conn *ib_conn, struct iser_tx_desc *tx_desc);
 360
 361 int iser_dma_map_task_data(struct iscsi_iser_task *iser_task,
 362                             struct iser_data_buf       *data,
 363                             enum   iser_data_dir       iser_dir,
 364                             enum   dma_data_direction  dma_dir);
 365
 366 void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task);
 367 int  iser_initialize_task_headers(struct iscsi_task *task,
 368                         struct iser_tx_desc *tx_desc);
 369 #endif