sysdeps/unix/sysv/linux/scsi/sg.h

   1 /* Copyright (C) 1997-2014 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 /*
  19    History:
  20     Started: Aug 9 by Lawrence Foard (entropy@world.std.com), to allow user
  21      process control of SCSI devices.
  22     Development Sponsored by Killy Corp. NY NY
  23 */
  24
  25 #ifndef _SCSI_SG_H
  26 #define _SCSI_SG_H      1
  27
  28 #include <features.h>
  29 #define __need_size_t
  30 #include <stddef.h>
  31
  32
  33 /* New interface introduced in the 3.x SG drivers follows */
  34
  35 /* Same structure as used by readv() Linux system call. It defines one
  36    scatter-gather element. */
  37 typedef struct sg_iovec
  38 {
  39   void * iov_base;            /* Starting address  */
  40   size_t iov_len;             /* Length in bytes  */
  41 } sg_iovec_t;
  42
  43
  44 typedef struct sg_io_hdr
  45 {
  46   int interface_id;           /* [i] 'S' for SCSI generic (required) */
  47   int dxfer_direction;        /* [i] data transfer direction  */
  48   unsigned char cmd_len;      /* [i] SCSI command length ( <= 16 bytes) */
  49   unsigned char mx_sb_len;    /* [i] max length to write to sbp */
  50   unsigned short int iovec_count; /* [i] 0 implies no scatter gather */
  51   unsigned int dxfer_len;     /* [i] byte count of data transfer */
  52   void * dxferp;              /* [i], [*io] points to data transfer memory
  53                                  or scatter gather list */
  54   unsigned char * cmdp;       /* [i], [*i] points to command to perform */
  55   unsigned char * sbp;        /* [i], [*o] points to sense_buffer memory */
  56   unsigned int timeout;       /* [i] MAX_UINT->no timeout (unit: millisec) */
  57   unsigned int flags;         /* [i] 0 -> default, see SG_FLAG... */
  58   int pack_id;                /* [i->o] unused internally (normally) */
  59   void * usr_ptr;             /* [i->o] unused internally */
  60   unsigned char status;       /* [o] scsi status */
  61   unsigned char masked_status;/* [o] shifted, masked scsi status */
  62   unsigned char msg_status;   /* [o] messaging level data (optional) */
  63   unsigned char sb_len_wr;    /* [o] byte count actually written to sbp */
  64   unsigned short int host_status; /* [o] errors from host adapter */
  65   unsigned short int driver_status;/* [o] errors from software driver */
  66   int resid;                  /* [o] dxfer_len - actual_transferred */
  67   unsigned int duration;      /* [o] time taken by cmd (unit: millisec) */
  68   unsigned int info;          /* [o] auxiliary information */
  69 } sg_io_hdr_t;
  70
  71
  72 /* Use negative values to flag difference from original sg_header structure.  */
  73 #define SG_DXFER_NONE -1        /* e.g. a SCSI Test Unit Ready command */
  74 #define SG_DXFER_TO_DEV -2      /* e.g. a SCSI WRITE command */
  75 #define SG_DXFER_FROM_DEV -3    /* e.g. a SCSI READ command */
  76 #define SG_DXFER_TO_FROM_DEV -4 /* treated like SG_DXFER_FROM_DEV with the
  77                                    additional property than during indirect
  78                                    IO the user buffer is copied into the
  79                                    kernel buffers before the transfer */
  80
  81
  82 /* following flag values can be "or"-ed together */
  83 #define SG_FLAG_DIRECT_IO 1     /* default is indirect IO */
  84 #define SG_FLAG_LUN_INHIBIT 2   /* default is to put device's lun into */
  85                                 /* the 2nd byte of SCSI command */
  86 #define SG_FLAG_NO_DXFER 0x10000 /* no transfer of kernel buffers to/from */
  87                                 /* user space (debug indirect IO) */
  88
  89 /* The following 'info' values are "or"-ed together.  */
  90 #define SG_INFO_OK_MASK 0x1
  91 #define SG_INFO_OK      0x0     /* no sense, host nor driver "noise" */
  92 #define SG_INFO_CHECK   0x1     /* something abnormal happened */
  93
  94 #define SG_INFO_DIRECT_IO_MASK  0x6
  95 #define SG_INFO_INDIRECT_IO     0x0     /* data xfer via kernel buffers (or no xfer) */
  96 #define SG_INFO_DIRECT_IO       0x2     /* direct IO requested and performed */
  97 #define SG_INFO_MIXED_IO        0x4     /* part direct, part indirect IO */
  98
  99
 100 /* Request information about a specific SG device, used by
 101    SG_GET_SCSI_ID ioctl ().  */
 102 struct sg_scsi_id {
 103   /* Host number as in "scsi<n>" where 'n' is one of 0, 1, 2 etc.  */
 104   int host_no;
 105   int channel;
 106   /* SCSI id of target device.  */
 107   int scsi_id;
 108   int lun;
 109   /* TYPE_... defined in <scsi/scsi.h>.  */
 110   int scsi_type;
 111   /* Host (adapter) maximum commands per lun.  */
 112   short int h_cmd_per_lun;
 113   /* Device (or adapter) maximum queue length.  */
 114   short int d_queue_depth;
 115   /* Unused, set to 0 for now.  */
 116   int unused[2];
 117 };
 118
 119 /* Used by SG_GET_REQUEST_TABLE ioctl().  */
 120 typedef struct sg_req_info {
 121     char req_state;     /* 0 -> not used, 1 -> written, 2 -> ready to read */
 122     char orphan;        /* 0 -> normal request, 1 -> from interruped SG_IO */
 123     char sg_io_owned;   /* 0 -> complete with read(), 1 -> owned by SG_IO */
 124     char problem;       /* 0 -> no problem detected, 1 -> error to report */
 125     int pack_id;        /* pack_id associated with request */
 126     void * usr_ptr;     /* user provided pointer (in new interface) */
 127     unsigned int duration; /* millisecs elapsed since written (req_state==1)
 128                               or request duration (req_state==2) */
 129     int unused;
 130 } sg_req_info_t;
 131
 132
 133 /* IOCTLs: Those ioctls that are relevant to the SG 3.x drivers follow.
 134  [Those that only apply to the SG 2.x drivers are at the end of the file.]
 135  (_GET_s yield result via 'int *' 3rd argument unless otherwise indicated) */
 136
 137 #define SG_EMULATED_HOST 0x2203 /* true for emulated host adapter (ATAPI) */
 138
 139 /* Used to configure SCSI command transformation layer for ATAPI devices */
 140 /* Only supported by the ide-scsi driver */
 141 #define SG_SET_TRANSFORM 0x2204 /* N.B. 3rd arg is not pointer but value: */
 142                       /* 3rd arg = 0 to disable transform, 1 to enable it */
 143 #define SG_GET_TRANSFORM 0x2205
 144
 145 #define SG_SET_RESERVED_SIZE 0x2275  /* request a new reserved buffer size */
 146 #define SG_GET_RESERVED_SIZE 0x2272  /* actual size of reserved buffer */
 147
 148 /* The following ioctl has a 'sg_scsi_id_t *' object as its 3rd argument. */
 149 #define SG_GET_SCSI_ID 0x2276   /* Yields fd's bus, chan, dev, lun + type */
 150 /* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN */
 151
 152 /* Override host setting and always DMA using low memory ( <16MB on i386) */
 153 #define SG_SET_FORCE_LOW_DMA 0x2279  /* 0-> use adapter setting, 1-> force */
 154 #define SG_GET_LOW_DMA 0x227a   /* 0-> use all ram for dma; 1-> low dma ram */
 155
 156 /* When SG_SET_FORCE_PACK_ID set to 1, pack_id is input to read() which
 157    tries to fetch a packet with a matching pack_id, waits, or returns EAGAIN.
 158    If pack_id is -1 then read oldest waiting. When ...FORCE_PACK_ID set to 0
 159    then pack_id ignored by read() and oldest readable fetched. */
 160 #define SG_SET_FORCE_PACK_ID 0x227b
 161 #define SG_GET_PACK_ID 0x227c /* Yields oldest readable pack_id (or -1) */
 162
 163 #define SG_GET_NUM_WAITING 0x227d /* Number of commands awaiting read() */
 164
 165 /* Yields max scatter gather tablesize allowed by current host adapter */
 166 #define SG_GET_SG_TABLESIZE 0x227F  /* 0 implies can't do scatter gather */
 167
 168 #define SG_GET_VERSION_NUM 0x2282 /* Example: version 2.1.34 yields 20134 */
 169
 170 /* Returns -EBUSY if occupied. 3rd argument pointer to int (see next) */
 171 #define SG_SCSI_RESET 0x2284
 172 /* Associated values that can be given to SG_SCSI_RESET follow */
 173 #define SG_SCSI_RESET_NOTHING   0
 174 #define SG_SCSI_RESET_DEVICE    1
 175 #define SG_SCSI_RESET_BUS       2
 176 #define SG_SCSI_RESET_HOST      3
 177
 178 /* synchronous SCSI command ioctl, (only in version 3 interface) */
 179 #define SG_IO 0x2285   /* similar effect as write() followed by read() */
 180
 181 #define SG_GET_REQUEST_TABLE 0x2286   /* yields table of active requests */
 182
 183 /* How to treat EINTR during SG_IO ioctl(), only in SG 3.x series */
 184 #define SG_SET_KEEP_ORPHAN 0x2287 /* 1 -> hold for read(), 0 -> drop (def) */
 185 #define SG_GET_KEEP_ORPHAN 0x2288
 186
 187
 188 #define SG_SCATTER_SZ (8 * 4096)  /* PAGE_SIZE not available to user */
 189 /* Largest size (in bytes) a single scatter-gather list element can have.
 190    The value must be a power of 2 and <= (PAGE_SIZE * 32) [131072 bytes on
 191    i386]. The minimum value is PAGE_SIZE. If scatter-gather not supported
 192    by adapter then this value is the largest data block that can be
 193    read/written by a single scsi command. The user can find the value of
 194    PAGE_SIZE by calling getpagesize() defined in unistd.h . */
 195
 196 #define SG_DEFAULT_RETRIES 1
 197
 198 /* Defaults, commented if they differ from original sg driver */
 199 #define SG_DEF_FORCE_LOW_DMA 0  /* was 1 -> memory below 16MB on i386 */
 200 #define SG_DEF_FORCE_PACK_ID 0
 201 #define SG_DEF_KEEP_ORPHAN 0
 202 #define SG_DEF_RESERVED_SIZE SG_SCATTER_SZ /* load time option */
 203
 204 /* maximum outstanding requests, write() yields EDOM if exceeded */
 205 #define SG_MAX_QUEUE 16
 206
 207 #define SG_BIG_BUFF SG_DEF_RESERVED_SIZE    /* for backward compatibility */
 208
 209 /* Alternate style type names, "..._t" variants preferred */
 210 typedef struct sg_io_hdr Sg_io_hdr;
 211 typedef struct sg_io_vec Sg_io_vec;
 212 typedef struct sg_scsi_id Sg_scsi_id;
 213 typedef struct sg_req_info Sg_req_info;
 214
 215
 216 /* vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv */
 217 /*   The older SG interface based on the 'sg_header' structure follows.   */
 218 /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
 219
 220 #define SG_MAX_SENSE 16   /* this only applies to the sg_header interface */
 221
 222 struct sg_header
 223  {
 224    /* Length of incoming packet (including header).  */
 225    int pack_len;
 226    /* Maximal length of expected reply.  */
 227    int reply_len;
 228    /* Id number of packet.  */
 229    int pack_id;
 230    /* 0==ok, otherwise error number.  */
 231    int result;
 232    /* Force 12 byte command length for group 6 & 7 commands.  */
 233    unsigned int twelve_byte:1;
 234    /* SCSI status from target.  */
 235    unsigned int target_status:5;
 236    /* Host status (see "DID" codes).  */
 237    unsigned int host_status:8;
 238    /* Driver status+suggestion.  */
 239    unsigned int driver_status:8;
 240    /* Unused.  */
 241    unsigned int other_flags:10;
 242    /* Output in 3 cases:
 243       when target_status is CHECK_CONDITION or
 244       when target_status is COMMAND_TERMINATED or
 245       when (driver_status & DRIVER_SENSE) is true.  */
 246    unsigned char sense_buffer[SG_MAX_SENSE];
 247  };
 248
 249
 250 /* IOCTLs: The following are not required (or ignored) when the sg_io_hdr_t
 251            interface is used. They are kept for backward compatibility with
 252            the original and version 2 drivers. */
 253
 254 #define SG_SET_TIMEOUT          0x2201  /* Set timeout; *(int *)arg==timeout.  */
 255 #define SG_GET_TIMEOUT          0x2202  /* Get timeout; return timeout.  */
 256
 257 /* Get/set command queuing state per fd (default is SG_DEF_COMMAND_Q). */
 258 #define SG_GET_COMMAND_Q        0x2270  /* Yields 0 (queuing off) or 1 (on).  */
 259 #define SG_SET_COMMAND_Q        0x2271  /* Change queuing state with 0 or 1.  */
 260
 261 /* Turn on error sense trace (1..8), dump this device to log/console (9)
 262    or dump all sg device states ( >9 ) to log/console.  */
 263 #define SG_SET_DEBUG            0x227e  /* 0 -> turn off debug */
 264
 265 #define SG_NEXT_CMD_LEN         0x2283  /* Override SCSI command length with given
 266                                            number on the next write() on this file
 267                                            descriptor.  */
 268
 269 /* Defaults, commented if they differ from original sg driver */
 270 #define SG_DEFAULT_TIMEOUT (60*HZ) /* HZ == 'jiffies in 1 second' */
 271 #define SG_DEF_COMMAND_Q 0     /* command queuing is always on when
 272                                   the new interface is used */
 273 #define SG_DEF_UNDERRUN_FLAG 0
 274
 275
 276 #endif  /* scsi/sg.h */