aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/unix/sysv/linux/scsi/sg.h
blob: 0e154446abd76fa27b7acbd3bb6abf125dcf951d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
/* Copyright (C) 1997, 1998, 1999, 2000  Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/*
   History:
    Started: Aug 9 by Lawrence Foard (entropy@world.std.com), to allow user
     process control of SCSI devices.
    Development Sponsored by Killy Corp. NY NY
*/

#ifndef _SCSI_SG_H
#define _SCSI_SG_H	1

#include <features.h>


/* New interface introduced in the 3.x SG drivers follows */

/* Same structure as used by readv() Linux system call. It defines one
   scatter-gather element. */
typedef struct sg_iovec
{
  void * iov_base;            /* Starting address  */
  size_t iov_len;             /* Length in bytes  */
} sg_iovec_t;


typedef struct sg_io_hdr
{
  int interface_id;           /* [i] 'S' for SCSI generic (required) */
  int dxfer_direction;        /* [i] data transfer direction  */
  unsigned char cmd_len;      /* [i] SCSI command length ( <= 16 bytes) */
  unsigned char mx_sb_len;    /* [i] max length to write to sbp */
  unsigned short int iovec_count; /* [i] 0 implies no scatter gather */
  unsigned int dxfer_len;     /* [i] byte count of data transfer */
  void * dxferp;              /* [i], [*io] points to data transfer memory
				 or scatter gather list */
  unsigned char * cmdp;       /* [i], [*i] points to command to perform */
  unsigned char * sbp;        /* [i], [*o] points to sense_buffer memory */
  unsigned int timeout;       /* [i] MAX_UINT->no timeout (unit: millisec) */
  unsigned int flags;         /* [i] 0 -> default, see SG_FLAG... */
  int pack_id;                /* [i->o] unused internally (normally) */
  void * usr_ptr;             /* [i->o] unused internally */
  unsigned char status;       /* [o] scsi status */
  unsigned char masked_status;/* [o] shifted, masked scsi status */
  unsigned char msg_status;   /* [o] messaging level data (optional) */
  unsigned char sb_len_wr;    /* [o] byte count actually written to sbp */
  unsigned short int host_status; /* [o] errors from host adapter */
  unsigned short int driver_status;/* [o] errors from software driver */
  int resid;                  /* [o] dxfer_len - actual_transferred */
  unsigned int duration;      /* [o] time taken by cmd (unit: millisec) */
  unsigned int info;          /* [o] auxiliary information */
} sg_io_hdr_t;


/* Use negative values to flag difference from original sg_header structure.  */
#define SG_DXFER_NONE -1        /* e.g. a SCSI Test Unit Ready command */
#define SG_DXFER_TO_DEV -2      /* e.g. a SCSI WRITE command */
#define SG_DXFER_FROM_DEV -3    /* e.g. a SCSI READ command */
#define SG_DXFER_TO_FROM_DEV -4 /* treated like SG_DXFER_FROM_DEV with the
				   additional property than during indirect
				   IO the user buffer is copied into the
				   kernel buffers before the transfer */


/* following flag values can be "or"-ed together */
#define SG_FLAG_DIRECT_IO 1     /* default is indirect IO */
#define SG_FLAG_LUN_INHIBIT 2   /* default is to put device's lun into */
				/* the 2nd byte of SCSI command */
#define SG_FLAG_NO_DXFER 0x10000 /* no transfer of kernel buffers to/from */
				/* user space (debug indirect IO) */

/* The following 'info' values are "or"-ed together.  */
#define SG_INFO_OK_MASK	0x1
#define SG_INFO_OK	0x0	/* no sense, host nor driver "noise" */
#define SG_INFO_CHECK	0x1     /* something abnormal happened */

#define SG_INFO_DIRECT_IO_MASK	0x6
#define SG_INFO_INDIRECT_IO 	0x0	/* data xfer via kernel buffers (or no xfer) */
#define SG_INFO_DIRECT_IO 	0x2	/* direct IO requested and performed */
#define SG_INFO_MIXED_IO 	0x4	/* part direct, part indirect IO */


/* Request information about a specific SG device, used by
   SG_GET_SCSI_ID ioctl ().  */
struct sg_scsi_id {
  /* Host number as in "scsi<n>" where 'n' is one of 0, 1, 2 etc.  */
  int host_no;
  int channel;
  /* SCSI id of target device.  */
  int scsi_id;
  int lun;
  /* TYPE_... defined in <scsi/scsi.h>.  */
  int scsi_type;
  /* Host (adapter) maximum commands per lun.  */
  short int h_cmd_per_lun;
  /* Device (or adapter) maximum queue length.  */
  short int d_queue_depth;
  /* Unused, set to 0 for now.  */
  int unused[2];
};

/* Used by SG_GET_REQUEST_TABLE ioctl().  */
typedef struct sg_req_info {
    char req_state;     /* 0 -> not used, 1 -> written, 2 -> ready to read */
    char orphan;        /* 0 -> normal request, 1 -> from interruped SG_IO */
    char sg_io_owned;   /* 0 -> complete with read(), 1 -> owned by SG_IO */
    char problem;       /* 0 -> no problem detected, 1 -> error to report */
    int pack_id;        /* pack_id associated with request */
    void * usr_ptr;     /* user provided pointer (in new interface) */
    unsigned int duration; /* millisecs elapsed since written (req_state==1)
			      or request duration (req_state==2) */
    int unused;
} sg_req_info_t;


/* IOCTLs: Those ioctls that are relevant to the SG 3.x drivers follow.
 [Those that only apply to the SG 2.x drivers are at the end of the file.]
 (_GET_s yield result via 'int *' 3rd argument unless otherwise indicated) */

#define SG_EMULATED_HOST 0x2203 /* true for emulated host adapter (ATAPI) */

/* Used to configure SCSI command transformation layer for ATAPI devices */
/* Only supported by the ide-scsi driver */
#define SG_SET_TRANSFORM 0x2204 /* N.B. 3rd arg is not pointer but value: */
		      /* 3rd arg = 0 to disable transform, 1 to enable it */
#define SG_GET_TRANSFORM 0x2205

#define SG_SET_RESERVED_SIZE 0x2275  /* request a new reserved buffer size */
#define SG_GET_RESERVED_SIZE 0x2272  /* actual size of reserved buffer */

/* The following ioctl has a 'sg_scsi_id_t *' object as its 3rd argument. */
#define SG_GET_SCSI_ID 0x2276   /* Yields fd's bus, chan, dev, lun + type */
/* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN */

/* Override host setting and always DMA using low memory ( <16MB on i386) */
#define SG_SET_FORCE_LOW_DMA 0x2279  /* 0-> use adapter setting, 1-> force */
#define SG_GET_LOW_DMA 0x227a   /* 0-> use all ram for dma; 1-> low dma ram */

/* When SG_SET_FORCE_PACK_ID set to 1, pack_id is input to read() which
   tries to fetch a packet with a matching pack_id, waits, or returns EAGAIN.
   If pack_id is -1 then read oldest waiting. When ...FORCE_PACK_ID set to 0
   then pack_id ignored by read() and oldest readable fetched. */
#define SG_SET_FORCE_PACK_ID 0x227b
#define SG_GET_PACK_ID 0x227c /* Yields oldest readable pack_id (or -1) */

#define SG_GET_NUM_WAITING 0x227d /* Number of commands awaiting read() */

/* Yields max scatter gather tablesize allowed by current host adapter */
#define SG_GET_SG_TABLESIZE 0x227F  /* 0 implies can't do scatter gather */

#define SG_GET_VERSION_NUM 0x2282 /* Example: version 2.1.34 yields 20134 */

/* Returns -EBUSY if occupied. 3rd argument pointer to int (see next) */
#define SG_SCSI_RESET 0x2284
/* Associated values that can be given to SG_SCSI_RESET follow */
#define SG_SCSI_RESET_NOTHING	0
#define SG_SCSI_RESET_DEVICE	1
#define SG_SCSI_RESET_BUS	2
#define SG_SCSI_RESET_HOST	3

/* synchronous SCSI command ioctl, (only in version 3 interface) */
#define SG_IO 0x2285   /* similar effect as write() followed by read() */

#define SG_GET_REQUEST_TABLE 0x2286   /* yields table of active requests */

/* How to treat EINTR during SG_IO ioctl(), only in SG 3.x series */
#define SG_SET_KEEP_ORPHAN 0x2287 /* 1 -> hold for read(), 0 -> drop (def) */
#define SG_GET_KEEP_ORPHAN 0x2288


#define SG_SCATTER_SZ (8 * 4096)  /* PAGE_SIZE not available to user */
/* Largest size (in bytes) a single scatter-gather list element can have.
   The value must be a power of 2 and <= (PAGE_SIZE * 32) [131072 bytes on
   i386]. The minimum value is PAGE_SIZE. If scatter-gather not supported
   by adapter then this value is the largest data block that can be
   read/written by a single scsi command. The user can find the value of
   PAGE_SIZE by calling getpagesize() defined in unistd.h . */

#define SG_DEFAULT_RETRIES 1

/* Defaults, commented if they differ from original sg driver */
#define SG_DEF_FORCE_LOW_DMA 0  /* was 1 -> memory below 16MB on i386 */
#define SG_DEF_FORCE_PACK_ID 0
#define SG_DEF_KEEP_ORPHAN 0
#define SG_DEF_RESERVED_SIZE SG_SCATTER_SZ /* load time option */

/* maximum outstanding requests, write() yields EDOM if exceeded */
#define SG_MAX_QUEUE 16

#define SG_BIG_BUFF SG_DEF_RESERVED_SIZE    /* for backward compatibility */

/* Alternate style type names, "..._t" variants preferred */
typedef struct sg_io_hdr Sg_io_hdr;
typedef struct sg_io_vec Sg_io_vec;
typedef struct sg_scsi_id Sg_scsi_id;
typedef struct sg_req_info Sg_req_info;


/* vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv */
/*   The older SG interface based on the 'sg_header' structure follows.   */
/* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */

#define SG_MAX_SENSE 16   /* this only applies to the sg_header interface */

struct sg_header
 {
   /* Length of incoming packet (including header).  */
   int pack_len;
   /* Maximal length of expected reply.  */
   int reply_len;
   /* Id number of packet.  */
   int pack_id;
   /* 0==ok, otherwise error number.  */
   int result;
   /* Force 12 byte command length for group 6 & 7 commands.  */
   unsigned int twelve_byte:1;
   /* SCSI status from target.  */
   unsigned int target_status:5;
   /* Host status (see "DID" codes).  */
   unsigned int host_status:8;
   /* Driver status+suggestion.  */
   unsigned int driver_status:8;
   /* Unused.  */
   unsigned int other_flags:10;
   /* Output in 3 cases:
      when target_status is CHECK_CONDITION or
      when target_status is COMMAND_TERMINATED or
      when (driver_status & DRIVER_SENSE) is true.  */
   unsigned char sense_buffer[SG_MAX_SENSE];
 };


/* IOCTLs: The following are not required (or ignored) when the sg_io_hdr_t
	   interface is used. They are kept for backward compatibility with
	   the original and version 2 drivers. */

#define SG_SET_TIMEOUT		0x2201	/* Set timeout; *(int *)arg==timeout.  */
#define SG_GET_TIMEOUT		0x2202	/* Get timeout; return timeout.  */

/* Get/set command queuing state per fd (default is SG_DEF_COMMAND_Q). */
#define SG_GET_COMMAND_Q	0x2270	/* Yields 0 (queuing off) or 1 (on).  */
#define SG_SET_COMMAND_Q 	0x2271	/* Change queuing state with 0 or 1.  */

/* Turn on error sense trace (1..8), dump this device to log/console (9)
   or dump all sg device states ( >9 ) to log/console.  */
#define SG_SET_DEBUG		0x227e	/* 0 -> turn off debug */

#define SG_NEXT_CMD_LEN		0x2283	/* Override SCSI command length with given
					   number on the next write() on this file
					   descriptor.  */

/* Defaults, commented if they differ from original sg driver */
#define SG_DEFAULT_TIMEOUT (60*HZ) /* HZ == 'jiffies in 1 second' */
#define SG_DEF_COMMAND_Q 0     /* command queuing is always on when
				  the new interface is used */
#define SG_DEF_UNDERRUN_FLAG 0


#endif	/* scsi/sg.h */