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      1 /* Copyright (C) 1997, 1998, 1999, 2000  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, write to the Free
     16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
     17    02111-1307 USA.  */
     18 
     19 /*
     20    History:
     21     Started: Aug 9 by Lawrence Foard (entropy (at) world.std.com), to allow user
     22      process control of SCSI devices.
     23     Development Sponsored by Killy Corp. NY NY
     24 */
     25 
     26 #ifndef _SCSI_SG_H
     27 #define _SCSI_SG_H	1
     28 
     29 #include <features.h>
     30 
     31 
     32 /* New interface introduced in the 3.x SG drivers follows */
     33 
     34 /* Same structure as used by readv() Linux system call. It defines one
     35    scatter-gather element. */
     36 typedef struct sg_iovec
     37 {
     38   void * iov_base;            /* Starting address  */
     39   size_t iov_len;             /* Length in bytes  */
     40 } sg_iovec_t;
     41 
     42 
     43 typedef struct sg_io_hdr
     44 {
     45   int interface_id;           /* [i] 'S' for SCSI generic (required) */
     46   int dxfer_direction;        /* [i] data transfer direction  */
     47   unsigned char cmd_len;      /* [i] SCSI command length ( <= 16 bytes) */
     48   unsigned char mx_sb_len;    /* [i] max length to write to sbp */
     49   unsigned short int iovec_count; /* [i] 0 implies no scatter gather */
     50   unsigned int dxfer_len;     /* [i] byte count of data transfer */
     51   void * dxferp;              /* [i], [*io] points to data transfer memory
     52 				 or scatter gather list */
     53   unsigned char * cmdp;       /* [i], [*i] points to command to perform */
     54   unsigned char * sbp;        /* [i], [*o] points to sense_buffer memory */
     55   unsigned int timeout;       /* [i] MAX_UINT->no timeout (unit: millisec) */
     56   unsigned int flags;         /* [i] 0 -> default, see SG_FLAG... */
     57   int pack_id;                /* [i->o] unused internally (normally) */
     58   void * usr_ptr;             /* [i->o] unused internally */
     59   unsigned char status;       /* [o] scsi status */
     60   unsigned char masked_status;/* [o] shifted, masked scsi status */
     61   unsigned char msg_status;   /* [o] messaging level data (optional) */
     62   unsigned char sb_len_wr;    /* [o] byte count actually written to sbp */
     63   unsigned short int host_status; /* [o] errors from host adapter */
     64   unsigned short int driver_status;/* [o] errors from software driver */
     65   int resid;                  /* [o] dxfer_len - actual_transferred */
     66   unsigned int duration;      /* [o] time taken by cmd (unit: millisec) */
     67   unsigned int info;          /* [o] auxiliary information */
     68 } sg_io_hdr_t;
     69 
     70 
     71 /* Use negative values to flag difference from original sg_header structure.  */
     72 #define SG_DXFER_NONE -1        /* e.g. a SCSI Test Unit Ready command */
     73 #define SG_DXFER_TO_DEV -2      /* e.g. a SCSI WRITE command */
     74 #define SG_DXFER_FROM_DEV -3    /* e.g. a SCSI READ command */
     75 #define SG_DXFER_TO_FROM_DEV -4 /* treated like SG_DXFER_FROM_DEV with the
     76 				   additional property than during indirect
     77 				   IO the user buffer is copied into the
     78 				   kernel buffers before the transfer */
     79 
     80 
     81 /* following flag values can be "or"-ed together */
     82 #define SG_FLAG_DIRECT_IO 1     /* default is indirect IO */
     83 #define SG_FLAG_LUN_INHIBIT 2   /* default is to put device's lun into */
     84 				/* the 2nd byte of SCSI command */
     85 #define SG_FLAG_NO_DXFER 0x10000 /* no transfer of kernel buffers to/from */
     86 				/* user space (debug indirect IO) */
     87 
     88 /* The following 'info' values are "or"-ed together.  */
     89 #define SG_INFO_OK_MASK	0x1
     90 #define SG_INFO_OK	0x0	/* no sense, host nor driver "noise" */
     91 #define SG_INFO_CHECK	0x1     /* something abnormal happened */
     92 
     93 #define SG_INFO_DIRECT_IO_MASK	0x6
     94 #define SG_INFO_INDIRECT_IO 	0x0	/* data xfer via kernel buffers (or no xfer) */
     95 #define SG_INFO_DIRECT_IO 	0x2	/* direct IO requested and performed */
     96 #define SG_INFO_MIXED_IO 	0x4	/* part direct, part indirect IO */
     97 
     98 
     99 /* Request information about a specific SG device, used by
    100    SG_GET_SCSI_ID ioctl ().  */
    101 struct sg_scsi_id {
    102   /* Host number as in "scsi<n>" where 'n' is one of 0, 1, 2 etc.  */
    103   int host_no;
    104   int channel;
    105   /* SCSI id of target device.  */
    106   int scsi_id;
    107   int lun;
    108   /* TYPE_... defined in <scsi/scsi.h>.  */
    109   int scsi_type;
    110   /* Host (adapter) maximum commands per lun.  */
    111   short int h_cmd_per_lun;
    112   /* Device (or adapter) maximum queue length.  */
    113   short int d_queue_depth;
    114   /* Unused, set to 0 for now.  */
    115   int unused[2];
    116 };
    117 
    118 /* Used by SG_GET_REQUEST_TABLE ioctl().  */
    119 typedef struct sg_req_info {
    120     char req_state;     /* 0 -> not used, 1 -> written, 2 -> ready to read */
    121     char orphan;        /* 0 -> normal request, 1 -> from interruped SG_IO */
    122     char sg_io_owned;   /* 0 -> complete with read(), 1 -> owned by SG_IO */
    123     char problem;       /* 0 -> no problem detected, 1 -> error to report */
    124     int pack_id;        /* pack_id associated with request */
    125     void * usr_ptr;     /* user provided pointer (in new interface) */
    126     unsigned int duration; /* millisecs elapsed since written (req_state==1)
    127 			      or request duration (req_state==2) */
    128     int unused;
    129 } sg_req_info_t;
    130 
    131 
    132 /* IOCTLs: Those ioctls that are relevant to the SG 3.x drivers follow.
    133  [Those that only apply to the SG 2.x drivers are at the end of the file.]
    134  (_GET_s yield result via 'int *' 3rd argument unless otherwise indicated) */
    135 
    136 #define SG_EMULATED_HOST 0x2203 /* true for emulated host adapter (ATAPI) */
    137 
    138 /* Used to configure SCSI command transformation layer for ATAPI devices */
    139 /* Only supported by the ide-scsi driver */
    140 #define SG_SET_TRANSFORM 0x2204 /* N.B. 3rd arg is not pointer but value: */
    141 		      /* 3rd arg = 0 to disable transform, 1 to enable it */
    142 #define SG_GET_TRANSFORM 0x2205
    143 
    144 #define SG_SET_RESERVED_SIZE 0x2275  /* request a new reserved buffer size */
    145 #define SG_GET_RESERVED_SIZE 0x2272  /* actual size of reserved buffer */
    146 
    147 /* The following ioctl has a 'sg_scsi_id_t *' object as its 3rd argument. */
    148 #define SG_GET_SCSI_ID 0x2276   /* Yields fd's bus, chan, dev, lun + type */
    149 /* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN */
    150 
    151 /* Override host setting and always DMA using low memory ( <16MB on i386) */
    152 #define SG_SET_FORCE_LOW_DMA 0x2279  /* 0-> use adapter setting, 1-> force */
    153 #define SG_GET_LOW_DMA 0x227a   /* 0-> use all ram for dma; 1-> low dma ram */
    154 
    155 /* When SG_SET_FORCE_PACK_ID set to 1, pack_id is input to read() which
    156    tries to fetch a packet with a matching pack_id, waits, or returns EAGAIN.
    157    If pack_id is -1 then read oldest waiting. When ...FORCE_PACK_ID set to 0
    158    then pack_id ignored by read() and oldest readable fetched. */
    159 #define SG_SET_FORCE_PACK_ID 0x227b
    160 #define SG_GET_PACK_ID 0x227c /* Yields oldest readable pack_id (or -1) */
    161 
    162 #define SG_GET_NUM_WAITING 0x227d /* Number of commands awaiting read() */
    163 
    164 /* Yields max scatter gather tablesize allowed by current host adapter */
    165 #define SG_GET_SG_TABLESIZE 0x227F  /* 0 implies can't do scatter gather */
    166 
    167 #define SG_GET_VERSION_NUM 0x2282 /* Example: version 2.1.34 yields 20134 */
    168 
    169 /* Returns -EBUSY if occupied. 3rd argument pointer to int (see next) */
    170 #define SG_SCSI_RESET 0x2284
    171 /* Associated values that can be given to SG_SCSI_RESET follow */
    172 #define SG_SCSI_RESET_NOTHING	0
    173 #define SG_SCSI_RESET_DEVICE	1
    174 #define SG_SCSI_RESET_BUS	2
    175 #define SG_SCSI_RESET_HOST	3
    176 
    177 /* synchronous SCSI command ioctl, (only in version 3 interface) */
    178 #define SG_IO 0x2285   /* similar effect as write() followed by read() */
    179 
    180 #define SG_GET_REQUEST_TABLE 0x2286   /* yields table of active requests */
    181 
    182 /* How to treat EINTR during SG_IO ioctl(), only in SG 3.x series */
    183 #define SG_SET_KEEP_ORPHAN 0x2287 /* 1 -> hold for read(), 0 -> drop (def) */
    184 #define SG_GET_KEEP_ORPHAN 0x2288
    185 
    186 
    187 #define SG_SCATTER_SZ (8 * 4096)  /* PAGE_SIZE not available to user */
    188 /* Largest size (in bytes) a single scatter-gather list element can have.
    189    The value must be a power of 2 and <= (PAGE_SIZE * 32) [131072 bytes on
    190    i386]. The minimum value is PAGE_SIZE. If scatter-gather not supported
    191    by adapter then this value is the largest data block that can be
    192    read/written by a single scsi command. The user can find the value of
    193    PAGE_SIZE by calling getpagesize() defined in unistd.h . */
    194 
    195 #define SG_DEFAULT_RETRIES 1
    196 
    197 /* Defaults, commented if they differ from original sg driver */
    198 #define SG_DEF_FORCE_LOW_DMA 0  /* was 1 -> memory below 16MB on i386 */
    199 #define SG_DEF_FORCE_PACK_ID 0
    200 #define SG_DEF_KEEP_ORPHAN 0
    201 #define SG_DEF_RESERVED_SIZE SG_SCATTER_SZ /* load time option */
    202 
    203 /* maximum outstanding requests, write() yields EDOM if exceeded */
    204 #define SG_MAX_QUEUE 16
    205 
    206 #define SG_BIG_BUFF SG_DEF_RESERVED_SIZE    /* for backward compatibility */
    207 
    208 /* Alternate style type names, "..._t" variants preferred */
    209 typedef struct sg_io_hdr Sg_io_hdr;
    210 typedef struct sg_io_vec Sg_io_vec;
    211 typedef struct sg_scsi_id Sg_scsi_id;
    212 typedef struct sg_req_info Sg_req_info;
    213 
    214 
    215 /* vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv */
    216 /*   The older SG interface based on the 'sg_header' structure follows.   */
    217 /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    218 
    219 #define SG_MAX_SENSE 16   /* this only applies to the sg_header interface */
    220 
    221 struct sg_header
    222  {
    223    /* Length of incoming packet (including header).  */
    224    int pack_len;
    225    /* Maximal length of expected reply.  */
    226    int reply_len;
    227    /* Id number of packet.  */
    228    int pack_id;
    229    /* 0==ok, otherwise error number.  */
    230    int result;
    231    /* Force 12 byte command length for group 6 & 7 commands.  */
    232    unsigned int twelve_byte:1;
    233    /* SCSI status from target.  */
    234    unsigned int target_status:5;
    235    /* Host status (see "DID" codes).  */
    236    unsigned int host_status:8;
    237    /* Driver status+suggestion.  */
    238    unsigned int driver_status:8;
    239    /* Unused.  */
    240    unsigned int other_flags:10;
    241    /* Output in 3 cases:
    242       when target_status is CHECK_CONDITION or
    243       when target_status is COMMAND_TERMINATED or
    244       when (driver_status & DRIVER_SENSE) is true.  */
    245    unsigned char sense_buffer[SG_MAX_SENSE];
    246  };
    247 
    248 
    249 /* IOCTLs: The following are not required (or ignored) when the sg_io_hdr_t
    250 	   interface is used. They are kept for backward compatibility with
    251 	   the original and version 2 drivers. */
    252 
    253 #define SG_SET_TIMEOUT		0x2201	/* Set timeout; *(int *)arg==timeout.  */
    254 #define SG_GET_TIMEOUT		0x2202	/* Get timeout; return timeout.  */
    255 
    256 /* Get/set command queuing state per fd (default is SG_DEF_COMMAND_Q). */
    257 #define SG_GET_COMMAND_Q	0x2270	/* Yields 0 (queuing off) or 1 (on).  */
    258 #define SG_SET_COMMAND_Q 	0x2271	/* Change queuing state with 0 or 1.  */
    259 
    260 /* Turn on error sense trace (1..8), dump this device to log/console (9)
    261    or dump all sg device states ( >9 ) to log/console.  */
    262 #define SG_SET_DEBUG		0x227e	/* 0 -> turn off debug */
    263 
    264 #define SG_NEXT_CMD_LEN		0x2283	/* Override SCSI command length with given
    265 					   number on the next write() on this file
    266 					   descriptor.  */
    267 
    268 /* Defaults, commented if they differ from original sg driver */
    269 #define SG_DEFAULT_TIMEOUT (60*HZ) /* HZ == 'jiffies in 1 second' */
    270 #define SG_DEF_COMMAND_Q 0     /* command queuing is always on when
    271 				  the new interface is used */
    272 #define SG_DEF_UNDERRUN_FLAG 0
    273 
    274 
    275 #endif	/* scsi/sg.h */
    276