release/src-rt-6.x.4708/linux/linux-2.6.36/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/wait.h>
  49 #include <linux/sched.h>
  50 #include <linux/list.h>
  51 #include <linux/slab.h>
  52 #include <linux/dma-mapping.h>
  53 #include <linux/mutex.h>
  54 #include <linux/mempool.h>
  55 #include <linux/uio.h>
  56
  57 #include <linux/socket.h>
  58 #include <linux/in.h>
  59 #include <linux/in6.h>
  60
  61 #include <rdma/ib_verbs.h>
  62 #include <rdma/ib_fmr_pool.h>
  63 #include <rdma/rdma_cm.h>
  64
  65 #define DRV_NAME        "iser"
  66 #define PFX             DRV_NAME ": "
  67 #define DRV_VER         "0.1"
  68 #define DRV_DATE        "May 7th, 2006"
  69
  70 #define iser_dbg(fmt, arg...)                           \
  71         do {                                            \
  72                 if (iser_debug_level > 1)               \
  73                         printk(KERN_DEBUG PFX "%s:" fmt,\
  74                                 __func__ , ## arg);     \
  75         } while (0)
  76
  77 #define iser_warn(fmt, arg...)                          \
  78         do {                                            \
  79                 if (iser_debug_level > 0)               \
  80                         printk(KERN_DEBUG PFX "%s:" fmt,\
  81                                 __func__ , ## arg);     \
  82         } while (0)
  83
  84 #define iser_err(fmt, arg...)                           \
  85         do {                                            \
  86                 printk(KERN_ERR PFX "%s:" fmt,          \
  87                        __func__ , ## arg);              \
  88         } while (0)
  89
  90 #define SHIFT_4K        12
  91 #define SIZE_4K (1UL << SHIFT_4K)
  92 #define MASK_4K (~(SIZE_4K-1))
  93
  94                                         /* support upto 512KB in one RDMA */
  95 #define ISCSI_ISER_SG_TABLESIZE         (0x80000 >> SHIFT_4K)
  96 #define ISER_DEF_CMD_PER_LUN            128
  97
  98 /* QP settings */
  99 /* Maximal bounds on received asynchronous PDUs */
 100 #define ISER_MAX_RX_MISC_PDUS           4 /* NOOP_IN(2) , ASYNC_EVENT(2)   */
 101
 102 #define ISER_MAX_TX_MISC_PDUS           6 /* NOOP_OUT(2), TEXT(1),         *
 103                                            * SCSI_TMFUNC(2), LOGOUT(1) */
 104
 105 #define ISER_QP_MAX_RECV_DTOS           (ISCSI_DEF_XMIT_CMDS_MAX)
 106
 107 #define ISER_MIN_POSTED_RX              (ISCSI_DEF_XMIT_CMDS_MAX >> 2)
 108
 109 /* the max TX (send) WR supported by the iSER QP is defined by                 *
 110  * max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect   *
 111  * to have at max for SCSI command. The tx posting & completion handling code  *
 112  * supports -EAGAIN scheme where tx is suspended till the QP has room for more *
 113  * send WR. D=8 comes from 64K/8K                                              */
 114
 115 #define ISER_INFLIGHT_DATAOUTS          8
 116
 117 #define ISER_QP_MAX_REQ_DTOS            (ISCSI_DEF_XMIT_CMDS_MAX *    \
 118                                         (1 + ISER_INFLIGHT_DATAOUTS) + \
 119                                         ISER_MAX_TX_MISC_PDUS        + \
 120                                         ISER_MAX_RX_MISC_PDUS)
 121
 122 #define ISER_VER                        0x10
 123 #define ISER_WSV                        0x08
 124 #define ISER_RSV                        0x04
 125
 126 struct iser_hdr {
 127         u8      flags;
 128         u8      rsvd[3];
 129         __be32  write_stag; /* write rkey */
 130         __be64  write_va;
 131         __be32  read_stag;  /* read rkey */
 132         __be64  read_va;
 133 } __attribute__((packed));
 134
 135 /* Constant PDU lengths calculations */
 136 #define ISER_HEADERS_LEN  (sizeof(struct iser_hdr) + sizeof(struct iscsi_hdr))
 137
 138 #define ISER_RECV_DATA_SEG_LEN  128
 139 #define ISER_RX_PAYLOAD_SIZE    (ISER_HEADERS_LEN + ISER_RECV_DATA_SEG_LEN)
 140 #define ISER_RX_LOGIN_SIZE      (ISER_HEADERS_LEN + ISCSI_DEF_MAX_RECV_SEG_LEN)
 141
 142 /* Length of an object name string */
 143 #define ISER_OBJECT_NAME_SIZE               64
 144
 145 enum iser_ib_conn_state {
 146         ISER_CONN_INIT,            /* descriptor allocd, no conn          */
 147         ISER_CONN_PENDING,         /* in the process of being established */
 148         ISER_CONN_UP,              /* up and running                      */
 149         ISER_CONN_TERMINATING,     /* in the process of being terminated  */
 150         ISER_CONN_DOWN,            /* shut down                           */
 151         ISER_CONN_STATES_NUM
 152 };
 153
 154 enum iser_task_status {
 155         ISER_TASK_STATUS_INIT = 0,
 156         ISER_TASK_STATUS_STARTED,
 157         ISER_TASK_STATUS_COMPLETED
 158 };
 159
 160 enum iser_data_dir {
 161         ISER_DIR_IN = 0,           /* to initiator */
 162         ISER_DIR_OUT,              /* from initiator */
 163         ISER_DIRS_NUM
 164 };
 165
 166 struct iser_data_buf {
 167         void               *buf;      /* pointer to the sg list               */
 168         unsigned int       size;      /* num entries of this sg               */
 169         unsigned long      data_len;  /* total data len                       */
 170         unsigned int       dma_nents; /* returned by dma_map_sg               */
 171         char               *copy_buf; /* allocated copy buf for SGs unaligned *
 172                                        * for rdma which are copied            */
 173         struct scatterlist sg_single; /* SG-ified clone of a non SG SC or     *
 174                                        * unaligned SG                         */
 175   };
 176
 177 /* fwd declarations */
 178 struct iser_device;
 179 struct iscsi_iser_conn;
 180 struct iscsi_iser_task;
 181 struct iscsi_endpoint;
 182
 183 struct iser_mem_reg {
 184         u32  lkey;
 185         u32  rkey;
 186         u64  va;
 187         u64  len;
 188         void *mem_h;
 189         int  is_fmr;
 190 };
 191
 192 struct iser_regd_buf {
 193         struct iser_mem_reg     reg;        /* memory registration info        */
 194         void                    *virt_addr;
 195         struct iser_device      *device;    /* device->device for dma_unmap    */
 196         enum dma_data_direction direction;  /* direction for dma_unmap         */
 197         unsigned int            data_size;
 198 };
 199
 200 enum iser_desc_type {
 201         ISCSI_TX_CONTROL ,
 202         ISCSI_TX_SCSI_COMMAND,
 203         ISCSI_TX_DATAOUT
 204 };
 205
 206 struct iser_tx_desc {
 207         struct iser_hdr              iser_header;
 208         struct iscsi_hdr             iscsi_header;
 209         enum   iser_desc_type        type;
 210         u64                          dma_addr;
 211         /* sg[0] points to iser/iscsi headers, sg[1] optionally points to either
 212         of immediate data, unsolicited data-out or control (login,text) */
 213         struct ib_sge                tx_sg[2];
 214         int                          num_sge;
 215 };
 216
 217 #define ISER_RX_PAD_SIZE        (256 - (ISER_RX_PAYLOAD_SIZE + \
 218                                         sizeof(u64) + sizeof(struct ib_sge)))
 219 struct iser_rx_desc {
 220         struct iser_hdr              iser_header;
 221         struct iscsi_hdr             iscsi_header;
 222         char                         data[ISER_RECV_DATA_SEG_LEN];
 223         u64                          dma_addr;
 224         struct ib_sge                rx_sg;
 225         char                         pad[ISER_RX_PAD_SIZE];
 226 } __attribute__((packed));
 227
 228 struct iser_device {
 229         struct ib_device             *ib_device;
 230         struct ib_pd                 *pd;
 231         struct ib_cq                 *rx_cq;
 232         struct ib_cq                 *tx_cq;
 233         struct ib_mr                 *mr;
 234         struct tasklet_struct        cq_tasklet;
 235         struct ib_event_handler      event_handler;
 236         struct list_head             ig_list; /* entry in ig devices list */
 237         int                          refcount;
 238 };
 239
 240 struct iser_conn {
 241         struct iscsi_iser_conn       *iser_conn; /* iser conn for upcalls  */
 242         struct iscsi_endpoint        *ep;
 243         enum iser_ib_conn_state      state;         /* rdma connection state   */
 244         atomic_t                     refcount;
 245         spinlock_t                   lock;          /* used for state changes  */
 246         struct iser_device           *device;       /* device context          */
 247         struct rdma_cm_id            *cma_id;       /* CMA ID                  */
 248         struct ib_qp                 *qp;           /* QP                      */
 249         struct ib_fmr_pool           *fmr_pool;     /* pool of IB FMRs         */
 250         wait_queue_head_t            wait;          /* waitq for conn/disconn  */
 251         int                          post_recv_buf_count; /* posted rx count  */
 252         atomic_t                     post_send_buf_count; /* posted tx count   */
 253         char                         name[ISER_OBJECT_NAME_SIZE];
 254         struct iser_page_vec         *page_vec;     /* represents SG to fmr maps*
 255                                                      * maps serialized as tx is*/
 256         struct list_head             conn_list;       /* entry in ig conn list */
 257
 258         char                         *login_buf;
 259         u64                          login_dma;
 260         unsigned int                 rx_desc_head;
 261         struct iser_rx_desc          *rx_descs;
 262         struct ib_recv_wr            rx_wr[ISER_MIN_POSTED_RX];
 263 };
 264
 265 struct iscsi_iser_conn {
 266         struct iscsi_conn            *iscsi_conn;/* ptr to iscsi conn */
 267         struct iser_conn             *ib_conn;   /* iSER IB conn      */
 268 };
 269
 270 struct iscsi_iser_task {
 271         struct iser_tx_desc          desc;
 272         struct iscsi_iser_conn       *iser_conn;
 273         enum iser_task_status        status;
 274         int                          command_sent;  /* set if command  sent  */
 275         int                          dir[ISER_DIRS_NUM];      /* set if dir use*/
 276         struct iser_regd_buf         rdma_regd[ISER_DIRS_NUM];/* regd rdma buf */
 277         struct iser_data_buf         data[ISER_DIRS_NUM];     /* orig. data des*/
 278         struct iser_data_buf         data_copy[ISER_DIRS_NUM];/* contig. copy  */
 279         int                          headers_initialized;
 280 };
 281
 282 struct iser_page_vec {
 283         u64 *pages;
 284         int length;
 285         int offset;
 286         int data_size;
 287 };
 288
 289 struct iser_global {
 290         struct mutex      device_list_mutex;/*                   */
 291         struct list_head  device_list;       /* all iSER devices */
 292         struct mutex      connlist_mutex;
 293         struct list_head  connlist;             /* all iSER IB connections */
 294
 295         struct kmem_cache *desc_cache;
 296 };
 297
 298 extern struct iser_global ig;
 299 extern int iser_debug_level;
 300
 301 /* allocate connection resources needed for rdma functionality */
 302 int iser_conn_set_full_featured_mode(struct iscsi_conn *conn);
 303
 304 int iser_send_control(struct iscsi_conn *conn,
 305                       struct iscsi_task *task);
 306
 307 int iser_send_command(struct iscsi_conn *conn,
 308                       struct iscsi_task *task);
 309
 310 int iser_send_data_out(struct iscsi_conn *conn,
 311                        struct iscsi_task *task,
 312                        struct iscsi_data *hdr);
 313
 314 void iscsi_iser_recv(struct iscsi_conn *conn,
 315                      struct iscsi_hdr       *hdr,
 316                      char                   *rx_data,
 317                      int                    rx_data_len);
 318
 319 void iser_conn_init(struct iser_conn *ib_conn);
 320
 321 void iser_conn_get(struct iser_conn *ib_conn);
 322
 323 int iser_conn_put(struct iser_conn *ib_conn, int destroy_cma_id_allowed);
 324
 325 void iser_conn_terminate(struct iser_conn *ib_conn);
 326
 327 void iser_rcv_completion(struct iser_rx_desc *desc,
 328                          unsigned long    dto_xfer_len,
 329                         struct iser_conn *ib_conn);
 330
 331 void iser_snd_completion(struct iser_tx_desc *desc, struct iser_conn *ib_conn);
 332
 333 void iser_task_rdma_init(struct iscsi_iser_task *task);
 334
 335 void iser_task_rdma_finalize(struct iscsi_iser_task *task);
 336
 337 void iser_free_rx_descriptors(struct iser_conn *ib_conn);
 338
 339 void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_task *task,
 340                                      enum iser_data_dir         cmd_dir);
 341
 342 int  iser_reg_rdma_mem(struct iscsi_iser_task *task,
 343                        enum   iser_data_dir        cmd_dir);
 344
 345 int  iser_connect(struct iser_conn   *ib_conn,
 346                   struct sockaddr_in *src_addr,
 347                   struct sockaddr_in *dst_addr,
 348                   int                non_blocking);
 349
 350 int  iser_reg_page_vec(struct iser_conn     *ib_conn,
 351                        struct iser_page_vec *page_vec,
 352                        struct iser_mem_reg  *mem_reg);
 353
 354 void iser_unreg_mem(struct iser_mem_reg *mem_reg);
 355
 356 int  iser_post_recvl(struct iser_conn *ib_conn);
 357 int  iser_post_recvm(struct iser_conn *ib_conn, int count);
 358 int  iser_post_send(struct iser_conn *ib_conn, struct iser_tx_desc *tx_desc);
 359
 360 int iser_dma_map_task_data(struct iscsi_iser_task *iser_task,
 361                             struct iser_data_buf       *data,
 362                             enum   iser_data_dir       iser_dir,
 363                             enum   dma_data_direction  dma_dir);
 364
 365 void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task);
 366 int  iser_initialize_task_headers(struct iscsi_task *task,
 367                         struct iser_tx_desc *tx_desc);
 368 #endif