Edit File: sg.h
/* 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 Lesser General Public License as published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ /* 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 */