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#ifndef _ST_H
#define _ST_H
#include <linux/completion.h>
#include <linux/mutex.h>
#include <linux/kref.h>
#include <scsi/scsi_cmnd.h>
/* Descriptor for analyzed sense data */
struct st_cmdstatus {
int midlevel_result;
struct scsi_sense_hdr sense_hdr;
int have_sense;
int residual;
u64 uremainder64;
u8 flags;
u8 remainder_valid;
u8 fixed_format;
u8 deferred;
};
struct scsi_tape;
/* scsi tape command */
struct st_request {
unsigned char cmd[MAX_COMMAND_SIZE];
unsigned char sense[SCSI_SENSE_BUFFERSIZE];
int result;
struct scsi_tape *stp;
struct completion *waiting;
struct bio *bio;
};
/* The tape buffer descriptor. */
struct st_buffer {
unsigned char dma; /* DMA-able buffer */
unsigned char cleared; /* internal buffer cleared after open? */
unsigned short do_dio; /* direct i/o set up? */
int buffer_size;
int buffer_blocks;
int buffer_bytes;
int read_pointer;
int writing;
int syscall_result;
struct st_request *last_SRpnt;
struct st_cmdstatus cmdstat;
struct page **reserved_pages;
int reserved_page_order;
struct page **mapped_pages;
struct rq_map_data map_data;
unsigned char *b_data;
unsigned short use_sg; /* zero or max number of s/g segments for this adapter */
unsigned short sg_segs; /* number of segments in s/g list */
unsigned short frp_segs; /* number of buffer segments */
};
/* The tape mode definition */
struct st_modedef {
unsigned char defined;
unsigned char sysv; /* SYS V semantics? */
unsigned char do_async_writes;
unsigned char do_buffer_writes;
unsigned char do_read_ahead;
unsigned char defaults_for_writes;
unsigned char default_compression; /* 0 = don't touch, etc */
short default_density; /* Forced density, -1 = no value */
int default_blksize; /* Forced blocksize, -1 = no value */
struct scsi_tape *tape;
struct device *devs[2]; /* Auto-rewind and non-rewind devices */
struct cdev *cdevs[2]; /* Auto-rewind and non-rewind devices */
};
/* Number of modes can be changed by changing ST_NBR_MODE_BITS. The maximum
number of modes is 16 (ST_NBR_MODE_BITS 4) */
#define ST_NBR_MODE_BITS 2
#define ST_NBR_MODES (1 << ST_NBR_MODE_BITS)
#define ST_MODE_SHIFT (7 - ST_NBR_MODE_BITS)
#define ST_MODE_MASK ((ST_NBR_MODES - 1) << ST_MODE_SHIFT)
#define ST_MAX_TAPES (1 << (20 - (ST_NBR_MODE_BITS + 1)))
#define ST_MAX_TAPE_ENTRIES (ST_MAX_TAPES << (ST_NBR_MODE_BITS + 1))
/* The status related to each partition */
struct st_partstat {
unsigned char rw;
unsigned char eof;
unsigned char at_sm;
unsigned char last_block_valid;
u32 last_block_visited;
int drv_block; /* The block where the drive head is */
int drv_file;
};
/* Tape statistics */
struct scsi_tape_stats {
atomic64_t read_byte_cnt; /* bytes read */
atomic64_t write_byte_cnt; /* bytes written */
atomic64_t in_flight; /* Number of I/Os in flight */
atomic64_t read_cnt; /* Count of read requests */
atomic64_t write_cnt; /* Count of write requests */
atomic64_t other_cnt; /* Count of other requests either
* implicit or from user space
* ioctl. */
atomic64_t resid_cnt; /* Count of resid_len > 0 */
atomic64_t tot_read_time; /* ktime spent completing reads */
atomic64_t tot_write_time; /* ktime spent completing writes */
atomic64_t tot_io_time; /* ktime spent doing any I/O */
ktime_t read_time; /* holds ktime request was queued */
ktime_t write_time; /* holds ktime request was queued */
ktime_t other_time; /* holds ktime request was queued */
atomic_t last_read_size; /* Number of bytes issued for last read */
atomic_t last_write_size; /* Number of bytes issued for last write */
};
#define ST_NBR_PARTITIONS 4
/* The tape drive descriptor */
struct scsi_tape {
struct scsi_driver *driver;
struct scsi_device *device;
struct mutex lock; /* For serialization */
struct completion wait; /* For SCSI commands */
struct st_buffer *buffer;
int index;
/* Drive characteristics */
unsigned char omit_blklims;
unsigned char do_auto_lock;
unsigned char can_bsr;
unsigned char can_partitions;
unsigned char two_fm;
unsigned char fast_mteom;
unsigned char immediate;
unsigned char restr_dma;
unsigned char scsi2_logical;
unsigned char default_drvbuffer; /* 0xff = don't touch, value 3 bits */
unsigned char cln_mode; /* 0 = none, otherwise sense byte nbr */
unsigned char cln_sense_value;
unsigned char cln_sense_mask;
unsigned char use_pf; /* Set Page Format bit in all mode selects? */
unsigned char try_dio; /* try direct i/o in general? */
unsigned char try_dio_now; /* try direct i/o before next close? */
unsigned char c_algo; /* compression algorithm */
unsigned char pos_unknown; /* after reset position unknown */
unsigned char sili; /* use SILI when reading in variable b mode */
unsigned char immediate_filemark; /* write filemark immediately */
int tape_type;
int long_timeout; /* timeout for commands known to take long time */
/* Mode characteristics */
struct st_modedef modes[ST_NBR_MODES];
int current_mode;
/* Status variables */
int partition;
int new_partition;
int nbr_partitions; /* zero until partition support enabled */
struct st_partstat ps[ST_NBR_PARTITIONS];
unsigned char dirty;
unsigned char ready;
unsigned char write_prot;
unsigned char drv_write_prot;
unsigned char in_use;
unsigned char blksize_changed;
unsigned char density_changed;
unsigned char compression_changed;
unsigned char drv_buffer;
unsigned char density;
unsigned char door_locked;
unsigned char autorew_dev; /* auto-rewind device */
unsigned char rew_at_close; /* rewind necessary at close */
unsigned char inited;
unsigned char cleaning_req; /* cleaning requested? */
int block_size;
int min_block;
int max_block;
int recover_count; /* From tape opening */
int recover_reg; /* From last status call */
#if DEBUG
unsigned char write_pending;
int nbr_finished;
int nbr_waits;
int nbr_requests;
int nbr_dio;
int nbr_pages;
unsigned char last_cmnd[6];
unsigned char last_sense[16];
#endif
struct gendisk *disk;
struct kref kref;
struct scsi_tape_stats *stats;
};
/* Bit masks for use_pf */
#define USE_PF 1
#define PF_TESTED 2
/* Values of eof */
#define ST_NOEOF 0
#define ST_FM_HIT 1
#define ST_FM 2
#define ST_EOM_OK 3
#define ST_EOM_ERROR 4
#define ST_EOD_1 5
#define ST_EOD_2 6
#define ST_EOD 7
/* EOD hit while reading => ST_EOD_1 => return zero => ST_EOD_2 =>
return zero => ST_EOD, return ENOSPC */
/* When writing: ST_EOM_OK == early warning found, write OK
ST_EOD_1 == allow trying new write after early warning
ST_EOM_ERROR == early warning found, not able to write all */
/* Values of rw */
#define ST_IDLE 0
#define ST_READING 1
#define ST_WRITING 2
/* Values of ready state */
#define ST_READY 0
#define ST_NOT_READY 1
#define ST_NO_TAPE 2
/* Values for door lock state */
#define ST_UNLOCKED 0
#define ST_LOCKED_EXPLICIT 1
#define ST_LOCKED_AUTO 2
#define ST_LOCK_FAILS 3
/* Positioning SCSI-commands for Tandberg, etc. drives */
#define QFA_REQUEST_BLOCK 0x02
#define QFA_SEEK_BLOCK 0x0c
/* Setting the binary options */
#define ST_DONT_TOUCH 0
#define ST_NO 1
#define ST_YES 2
#define EXTENDED_SENSE_START 18
/* Masks for some conditions in the sense data */
#define SENSE_FMK 0x80
#define SENSE_EOM 0x40
#define SENSE_ILI 0x20
#endif