xref: /openbmc/linux/include/scsi/sg.h (revision e65e175b)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _SCSI_GENERIC_H
3 #define _SCSI_GENERIC_H
4 
5 #include <linux/compiler.h>
6 
7 /*
8  * History:
9  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com), to allow user
10  *   process control of SCSI devices.
11  *  Development Sponsored by Killy Corp. NY NY
12  *
13  * Original driver (sg.h):
14  *       Copyright (C) 1992 Lawrence Foard
15  * Version 2 and 3 extensions to driver:
16  *	Copyright (C) 1998 - 2014 Douglas Gilbert
17  *
18  *  Version: 3.5.36 (20140603)
19  *  This version is for 2.6 and 3 series kernels.
20  *
21  * Documentation
22  * =============
23  * A web site for the SG device driver can be found at:
24  *	http://sg.danny.cz/sg  [alternatively check the MAINTAINERS file]
25  * The documentation for the sg version 3 driver can be found at:
26  *	http://sg.danny.cz/sg/p/sg_v3_ho.html
27  * Also see: <kernel_source>/Documentation/scsi/scsi-generic.rst
28  *
29  * For utility and test programs see: http://sg.danny.cz/sg/sg3_utils.html
30  */
31 
32 
33 typedef struct sg_iovec /* same structure as used by readv() Linux system */
34 {                       /* call. It defines one scatter-gather element. */
35     void __user *iov_base;      /* Starting address  */
36     size_t iov_len;             /* Length in bytes  */
37 } sg_iovec_t;
38 
39 
40 typedef struct sg_io_hdr
41 {
42     int interface_id;           /* [i] 'S' for SCSI generic (required) */
43     int dxfer_direction;        /* [i] data transfer direction  */
44     unsigned char cmd_len;      /* [i] SCSI command length */
45     unsigned char mx_sb_len;    /* [i] max length to write to sbp */
46     unsigned short iovec_count; /* [i] 0 implies no scatter gather */
47     unsigned int dxfer_len;     /* [i] byte count of data transfer */
48     void __user *dxferp;	/* [i], [*io] points to data transfer memory
49 					      or scatter gather list */
50     unsigned char __user *cmdp; /* [i], [*i] points to command to perform */
51     void __user *sbp;		/* [i], [*o] points to sense_buffer memory */
52     unsigned int timeout;       /* [i] MAX_UINT->no timeout (unit: millisec) */
53     unsigned int flags;         /* [i] 0 -> default, see SG_FLAG... */
54     int pack_id;                /* [i->o] unused internally (normally) */
55     void __user * usr_ptr;      /* [i->o] unused internally */
56     unsigned char status;       /* [o] scsi status */
57     unsigned char masked_status;/* [o] shifted, masked scsi status */
58     unsigned char msg_status;   /* [o] messaging level data (optional) */
59     unsigned char sb_len_wr;    /* [o] byte count actually written to sbp */
60     unsigned short host_status; /* [o] errors from host adapter */
61     unsigned short driver_status;/* [o] errors from software driver */
62     int resid;                  /* [o] dxfer_len - actual_transferred */
63     unsigned int duration;      /* [o] time taken by cmd (unit: millisec) */
64     unsigned int info;          /* [o] auxiliary information */
65 } sg_io_hdr_t;  /* 64 bytes long (on i386) */
66 
67 #if defined(__KERNEL__)
68 #include <linux/compat.h>
69 
70 struct compat_sg_io_hdr {
71 	compat_int_t interface_id;	/* [i] 'S' for SCSI generic (required) */
72 	compat_int_t dxfer_direction;	/* [i] data transfer direction  */
73 	unsigned char cmd_len;		/* [i] SCSI command length ( <= 16 bytes) */
74 	unsigned char mx_sb_len;	/* [i] max length to write to sbp */
75 	unsigned short iovec_count;	/* [i] 0 implies no scatter gather */
76 	compat_uint_t dxfer_len;	/* [i] byte count of data transfer */
77 	compat_uint_t dxferp;		/* [i], [*io] points to data transfer memory
78 						or scatter gather list */
79 	compat_uptr_t cmdp;		/* [i], [*i] points to command to perform */
80 	compat_uptr_t sbp;		/* [i], [*o] points to sense_buffer memory */
81 	compat_uint_t timeout;		/* [i] MAX_UINT->no timeout (unit: millisec) */
82 	compat_uint_t flags;		/* [i] 0 -> default, see SG_FLAG... */
83 	compat_int_t pack_id;		/* [i->o] unused internally (normally) */
84 	compat_uptr_t usr_ptr;		/* [i->o] unused internally */
85 	unsigned char status;		/* [o] scsi status */
86 	unsigned char masked_status;	/* [o] shifted, masked scsi status */
87 	unsigned char msg_status;	/* [o] messaging level data (optional) */
88 	unsigned char sb_len_wr;	/* [o] byte count actually written to sbp */
89 	unsigned short host_status;	/* [o] errors from host adapter */
90 	unsigned short driver_status;	/* [o] errors from software driver */
91 	compat_int_t resid;		/* [o] dxfer_len - actual_transferred */
92 	compat_uint_t duration;		/* [o] time taken by cmd (unit: millisec) */
93 	compat_uint_t info;		/* [o] auxiliary information */
94 };
95 #endif
96 
97 #define SG_INTERFACE_ID_ORIG 'S'
98 
99 /* Use negative values to flag difference from original sg_header structure */
100 #define SG_DXFER_NONE (-1)      /* e.g. a SCSI Test Unit Ready command */
101 #define SG_DXFER_TO_DEV (-2)    /* e.g. a SCSI WRITE command */
102 #define SG_DXFER_FROM_DEV (-3)  /* e.g. a SCSI READ command */
103 #define SG_DXFER_TO_FROM_DEV (-4) /* treated like SG_DXFER_FROM_DEV with the
104 				   additional property than during indirect
105 				   IO the user buffer is copied into the
106 				   kernel buffers before the transfer */
107 #define SG_DXFER_UNKNOWN (-5)   /* Unknown data direction */
108 
109 /* following flag values can be "or"-ed together */
110 #define SG_FLAG_DIRECT_IO 1     /* default is indirect IO */
111 #define SG_FLAG_UNUSED_LUN_INHIBIT 2   /* default is overwrite lun in SCSI */
112 				/* command block (when <= SCSI_2) */
113 #define SG_FLAG_MMAP_IO 4       /* request memory mapped IO */
114 #define SG_FLAG_NO_DXFER 0x10000 /* no transfer of kernel buffers to/from */
115 				/* user space (debug indirect IO) */
116 /* defaults:: for sg driver: Q_AT_HEAD; for block layer: Q_AT_TAIL */
117 #define SG_FLAG_Q_AT_TAIL 0x10
118 #define SG_FLAG_Q_AT_HEAD 0x20
119 
120 /* following 'info' values are "or"-ed together */
121 #define SG_INFO_OK_MASK 0x1
122 #define SG_INFO_OK 0x0          /* no sense, host nor driver "noise" */
123 #define SG_INFO_CHECK 0x1       /* something abnormal happened */
124 
125 #define SG_INFO_DIRECT_IO_MASK 0x6
126 #define SG_INFO_INDIRECT_IO 0x0 /* data xfer via kernel buffers (or no xfer) */
127 #define SG_INFO_DIRECT_IO 0x2   /* direct IO requested and performed */
128 #define SG_INFO_MIXED_IO 0x4    /* part direct, part indirect IO */
129 
130 /*
131  * Obsolete DRIVER_SENSE driver byte
132  *
133  * Originally the SCSI midlayer would set the DRIVER_SENSE driver byte when
134  * a sense code was generated and a sense buffer was allocated.
135  * However, as nowadays every scsi command has a sense code allocated this
136  * distinction became moot as one could check the sense buffer directly.
137  * Consequently this byte is not set anymore from the midlayer, but SG will
138  * keep setting this byte to be compatible with previous releases.
139  */
140 #define DRIVER_SENSE 0x08
141 /* Obsolete driver_byte() declaration */
142 #define driver_byte(result) (((result) >> 24) & 0xff)
143 
144 /*
145  *  Original linux SCSI Status codes. They are shifted 1 bit right
146  *  from those found in the SCSI standards.
147  */
148 
149 #define GOOD                 0x00
150 #define CHECK_CONDITION      0x01
151 #define CONDITION_GOOD       0x02
152 #define BUSY                 0x04
153 #define INTERMEDIATE_GOOD    0x08
154 #define INTERMEDIATE_C_GOOD  0x0a
155 #define RESERVATION_CONFLICT 0x0c
156 #define COMMAND_TERMINATED   0x11
157 #define QUEUE_FULL           0x14
158 #define ACA_ACTIVE           0x18
159 #define TASK_ABORTED         0x20
160 
161 /* Obsolete status_byte() declaration */
162 #define sg_status_byte(result) (((result) >> 1) & 0x7f)
163 
164 typedef struct sg_scsi_id { /* used by SG_GET_SCSI_ID ioctl() */
165     int host_no;        /* as in "scsi<n>" where 'n' is one of 0, 1, 2 etc */
166     int channel;
167     int scsi_id;        /* scsi id of target device */
168     int lun;
169     int scsi_type;      /* TYPE_... defined in scsi/scsi.h */
170     short h_cmd_per_lun;/* host (adapter) maximum commands per lun */
171     short d_queue_depth;/* device (or adapter) maximum queue length */
172     int unused[2];      /* probably find a good use, set 0 for now */
173 } sg_scsi_id_t; /* 32 bytes long on i386 */
174 
175 typedef struct sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
176     char req_state;     /* 0 -> not used, 1 -> written, 2 -> ready to read */
177     char orphan;        /* 0 -> normal request, 1 -> from interrupted SG_IO */
178     char sg_io_owned;   /* 0 -> complete with read(), 1 -> owned by SG_IO */
179     char problem;       /* 0 -> no problem detected, 1 -> error to report */
180     int pack_id;        /* pack_id associated with request */
181     void __user *usr_ptr;     /* user provided pointer (in new interface) */
182     unsigned int duration; /* millisecs elapsed since written (req_state==1)
183 			      or request duration (req_state==2) */
184     int unused;
185 } sg_req_info_t; /* 20 bytes long on i386 */
186 
187 
188 /* IOCTLs: Those ioctls that are relevant to the SG 3.x drivers follow.
189  [Those that only apply to the SG 2.x drivers are at the end of the file.]
190  (_GET_s yield result via 'int *' 3rd argument unless otherwise indicated) */
191 
192 #define SG_EMULATED_HOST 0x2203 /* true for emulated host adapter (ATAPI) */
193 
194 /* Used to configure SCSI command transformation layer for ATAPI devices */
195 /* Only supported by the ide-scsi driver */
196 #define SG_SET_TRANSFORM 0x2204 /* N.B. 3rd arg is not pointer but value: */
197 		      /* 3rd arg = 0 to disable transform, 1 to enable it */
198 #define SG_GET_TRANSFORM 0x2205
199 
200 #define SG_SET_RESERVED_SIZE 0x2275  /* request a new reserved buffer size */
201 #define SG_GET_RESERVED_SIZE 0x2272  /* actual size of reserved buffer */
202 
203 /* The following ioctl has a 'sg_scsi_id_t *' object as its 3rd argument. */
204 #define SG_GET_SCSI_ID 0x2276   /* Yields fd's bus, chan, dev, lun + type */
205 /* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN */
206 
207 /* Override host setting and always DMA using low memory ( <16MB on i386) */
208 #define SG_SET_FORCE_LOW_DMA 0x2279  /* 0-> use adapter setting, 1-> force */
209 #define SG_GET_LOW_DMA 0x227a   /* 0-> use all ram for dma; 1-> low dma ram */
210 
211 /* When SG_SET_FORCE_PACK_ID set to 1, pack_id is input to read() which
212    tries to fetch a packet with a matching pack_id, waits, or returns EAGAIN.
213    If pack_id is -1 then read oldest waiting. When ...FORCE_PACK_ID set to 0
214    then pack_id ignored by read() and oldest readable fetched. */
215 #define SG_SET_FORCE_PACK_ID 0x227b
216 #define SG_GET_PACK_ID 0x227c /* Yields oldest readable pack_id (or -1) */
217 
218 #define SG_GET_NUM_WAITING 0x227d /* Number of commands awaiting read() */
219 
220 /* Yields max scatter gather tablesize allowed by current host adapter */
221 #define SG_GET_SG_TABLESIZE 0x227F  /* 0 implies can't do scatter gather */
222 
223 #define SG_GET_VERSION_NUM 0x2282 /* Example: version 2.1.34 yields 20134 */
224 
225 /* Returns -EBUSY if occupied. 3rd argument pointer to int (see next) */
226 #define SG_SCSI_RESET 0x2284
227 /* Associated values that can be given to SG_SCSI_RESET follow.
228  * SG_SCSI_RESET_NO_ESCALATE may be OR-ed to the _DEVICE, _TARGET, _BUS
229  * or _HOST reset value so only that action is attempted. */
230 #define		SG_SCSI_RESET_NOTHING	0
231 #define		SG_SCSI_RESET_DEVICE	1
232 #define		SG_SCSI_RESET_BUS	2
233 #define		SG_SCSI_RESET_HOST	3
234 #define		SG_SCSI_RESET_TARGET	4
235 #define		SG_SCSI_RESET_NO_ESCALATE	0x100
236 
237 /* synchronous SCSI command ioctl, (only in version 3 interface) */
238 #define SG_IO 0x2285   /* similar effect as write() followed by read() */
239 
240 #define SG_GET_REQUEST_TABLE 0x2286   /* yields table of active requests */
241 
242 /* How to treat EINTR during SG_IO ioctl(), only in SG 3.x series */
243 #define SG_SET_KEEP_ORPHAN 0x2287 /* 1 -> hold for read(), 0 -> drop (def) */
244 #define SG_GET_KEEP_ORPHAN 0x2288
245 
246 /* yields scsi midlevel's access_count for this SCSI device */
247 #define SG_GET_ACCESS_COUNT 0x2289
248 
249 
250 #define SG_SCATTER_SZ (8 * 4096)
251 /* Largest size (in bytes) a single scatter-gather list element can have.
252    The value used by the driver is 'max(SG_SCATTER_SZ, PAGE_SIZE)'.
253    This value should be a power of 2 (and may be rounded up internally).
254    If scatter-gather is not supported by adapter then this value is the
255    largest data block that can be read/written by a single scsi command. */
256 
257 #define SG_DEFAULT_RETRIES 0
258 
259 /* Defaults, commented if they differ from original sg driver */
260 #define SG_DEF_FORCE_PACK_ID 0
261 #define SG_DEF_KEEP_ORPHAN 0
262 #define SG_DEF_RESERVED_SIZE SG_SCATTER_SZ /* load time option */
263 
264 /* maximum outstanding requests, write() yields EDOM if exceeded */
265 #define SG_MAX_QUEUE 16
266 
267 #define SG_BIG_BUFF SG_DEF_RESERVED_SIZE    /* for backward compatibility */
268 
269 /* Alternate style type names, "..._t" variants preferred */
270 typedef struct sg_io_hdr Sg_io_hdr;
271 typedef struct sg_io_vec Sg_io_vec;
272 typedef struct sg_scsi_id Sg_scsi_id;
273 typedef struct sg_req_info Sg_req_info;
274 
275 
276 /* vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv */
277 /*   The older SG interface based on the 'sg_header' structure follows.   */
278 /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
279 
280 #define SG_MAX_SENSE 16   /* this only applies to the sg_header interface */
281 
282 struct sg_header
283 {
284     int pack_len;    /* [o] reply_len (ie useless), ignored as input */
285     int reply_len;   /* [i] max length of expected reply (inc. sg_header) */
286     int pack_id;     /* [io] id number of packet (use ints >= 0) */
287     int result;      /* [o] 0==ok, else (+ve) Unix errno (best ignored) */
288     unsigned int twelve_byte:1;
289 	/* [i] Force 12 byte command length for group 6 & 7 commands  */
290     unsigned int target_status:5;   /* [o] scsi status from target */
291     unsigned int host_status:8;     /* [o] host status (see "DID" codes) */
292     unsigned int driver_status:8;   /* [o] driver status+suggestion */
293     unsigned int other_flags:10;    /* unused */
294     unsigned char sense_buffer[SG_MAX_SENSE]; /* [o] Output in 3 cases:
295 	   when target_status is CHECK_CONDITION or
296 	   when target_status is COMMAND_TERMINATED or
297 	   when (driver_status & DRIVER_SENSE) is true. */
298 };      /* This structure is 36 bytes long on i386 */
299 
300 
301 /* IOCTLs: The following are not required (or ignored) when the sg_io_hdr_t
302 	   interface is used. They are kept for backward compatibility with
303 	   the original and version 2 drivers. */
304 
305 #define SG_SET_TIMEOUT 0x2201  /* unit: jiffies (10ms on i386) */
306 #define SG_GET_TIMEOUT 0x2202  /* yield timeout as _return_ value */
307 
308 /* Get/set command queuing state per fd (default is SG_DEF_COMMAND_Q.
309    Each time a sg_io_hdr_t object is seen on this file descriptor, this
310    command queuing flag is set on (overriding the previous setting). */
311 #define SG_GET_COMMAND_Q 0x2270   /* Yields 0 (queuing off) or 1 (on) */
312 #define SG_SET_COMMAND_Q 0x2271   /* Change queuing state with 0 or 1 */
313 
314 /* Turn on/off error sense trace (1 and 0 respectively, default is off).
315    Try using: "# cat /proc/scsi/sg/debug" instead in the v3 driver */
316 #define SG_SET_DEBUG 0x227e    /* 0 -> turn off debug */
317 
318 #define SG_NEXT_CMD_LEN 0x2283  /* override SCSI command length with given
319 		   number on the next write() on this file descriptor */
320 
321 
322 /* Defaults, commented if they differ from original sg driver */
323 #ifdef __KERNEL__
324 #define SG_DEFAULT_TIMEOUT_USER	(60*USER_HZ) /* HZ == 'jiffies in 1 second' */
325 #else
326 #define SG_DEFAULT_TIMEOUT	(60*HZ)	     /* HZ == 'jiffies in 1 second' */
327 #endif
328 
329 #define SG_DEF_COMMAND_Q 0     /* command queuing is always on when
330 				  the new interface is used */
331 #define SG_DEF_UNDERRUN_FLAG 0
332 
333 #endif
334