xref: /openbmc/linux/drivers/scsi/st.h (revision e868d61272caa648214046a096e5a6bfc068dc8c)
1 
2 #ifndef _ST_H
3 #define _ST_H
4 
5 #include <linux/completion.h>
6 #include <linux/kref.h>
7 #include <scsi/scsi_cmnd.h>
8 
9 /* Descriptor for analyzed sense data */
10 struct st_cmdstatus {
11 	int midlevel_result;
12 	struct scsi_sense_hdr sense_hdr;
13 	int have_sense;
14 	u64 uremainder64;
15 	u8 flags;
16 	u8 remainder_valid;
17 	u8 fixed_format;
18 	u8 deferred;
19 };
20 
21 struct scsi_tape;
22 
23 /* scsi tape command */
24 struct st_request {
25 	unsigned char cmd[MAX_COMMAND_SIZE];
26 	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
27 	int result;
28 	struct scsi_tape *stp;
29 	struct completion *waiting;
30 };
31 
32 /* The tape buffer descriptor. */
33 struct st_buffer {
34 	unsigned char dma;	/* DMA-able buffer */
35 	unsigned char do_dio;   /* direct i/o set up? */
36 	int buffer_size;
37 	int buffer_blocks;
38 	int buffer_bytes;
39 	int read_pointer;
40 	int writing;
41 	int syscall_result;
42 	struct st_request *last_SRpnt;
43 	struct st_cmdstatus cmdstat;
44 	unsigned char *b_data;
45 	unsigned short use_sg;	/* zero or max number of s/g segments for this adapter */
46 	unsigned short sg_segs;		/* number of segments in s/g list */
47 	unsigned short orig_frp_segs;	/* number of segments allocated at first try */
48 	unsigned short frp_segs;	/* number of buffer segments */
49 	unsigned int frp_sg_current;	/* driver buffer length currently in s/g list */
50 	struct st_buf_fragment *frp;	/* the allocated buffer fragment list */
51 	struct scatterlist sg[1];	/* MUST BE last item */
52 };
53 
54 /* The tape buffer fragment descriptor */
55 struct st_buf_fragment {
56 	struct page *page;
57 	unsigned int length;
58 };
59 
60 /* The tape mode definition */
61 struct st_modedef {
62 	unsigned char defined;
63 	unsigned char sysv;	/* SYS V semantics? */
64 	unsigned char do_async_writes;
65 	unsigned char do_buffer_writes;
66 	unsigned char do_read_ahead;
67 	unsigned char defaults_for_writes;
68 	unsigned char default_compression;	/* 0 = don't touch, etc */
69 	short default_density;	/* Forced density, -1 = no value */
70 	int default_blksize;	/* Forced blocksize, -1 = no value */
71 	struct cdev *cdevs[2];  /* Auto-rewind and non-rewind devices */
72 };
73 
74 /* Number of modes can be changed by changing ST_NBR_MODE_BITS. The maximum
75    number of modes is 16 (ST_NBR_MODE_BITS 4) */
76 #define ST_NBR_MODE_BITS 2
77 #define ST_NBR_MODES (1 << ST_NBR_MODE_BITS)
78 #define ST_MODE_SHIFT (7 - ST_NBR_MODE_BITS)
79 #define ST_MODE_MASK ((ST_NBR_MODES - 1) << ST_MODE_SHIFT)
80 
81 #define ST_MAX_TAPES 128
82 #define ST_MAX_TAPE_ENTRIES  (ST_MAX_TAPES << (ST_NBR_MODE_BITS + 1))
83 
84 /* The status related to each partition */
85 struct st_partstat {
86 	unsigned char rw;
87 	unsigned char eof;
88 	unsigned char at_sm;
89 	unsigned char last_block_valid;
90 	u32 last_block_visited;
91 	int drv_block;		/* The block where the drive head is */
92 	int drv_file;
93 };
94 
95 #define ST_NBR_PARTITIONS 4
96 
97 /* The tape drive descriptor */
98 struct scsi_tape {
99 	struct scsi_driver *driver;
100 	struct scsi_device *device;
101 	struct semaphore lock;	/* For serialization */
102 	struct completion wait;	/* For SCSI commands */
103 	struct st_buffer *buffer;
104 
105 	/* Drive characteristics */
106 	unsigned char omit_blklims;
107 	unsigned char do_auto_lock;
108 	unsigned char can_bsr;
109 	unsigned char can_partitions;
110 	unsigned char two_fm;
111 	unsigned char fast_mteom;
112 	unsigned char immediate;
113 	unsigned char restr_dma;
114 	unsigned char scsi2_logical;
115 	unsigned char default_drvbuffer;	/* 0xff = don't touch, value 3 bits */
116 	unsigned char cln_mode;			/* 0 = none, otherwise sense byte nbr */
117 	unsigned char cln_sense_value;
118 	unsigned char cln_sense_mask;
119 	unsigned char use_pf;			/* Set Page Format bit in all mode selects? */
120 	unsigned char try_dio;			/* try direct i/o in general? */
121 	unsigned char try_dio_now;		/* try direct i/o before next close? */
122 	unsigned char c_algo;			/* compression algorithm */
123 	unsigned char pos_unknown;			/* after reset position unknown */
124 	int tape_type;
125 	int long_timeout;	/* timeout for commands known to take long time */
126 
127 	unsigned long max_pfn;	/* the maximum page number reachable by the HBA */
128 
129 	/* Mode characteristics */
130 	struct st_modedef modes[ST_NBR_MODES];
131 	int current_mode;
132 
133 	/* Status variables */
134 	int partition;
135 	int new_partition;
136 	int nbr_partitions;	/* zero until partition support enabled */
137 	struct st_partstat ps[ST_NBR_PARTITIONS];
138 	unsigned char dirty;
139 	unsigned char ready;
140 	unsigned char write_prot;
141 	unsigned char drv_write_prot;
142 	unsigned char in_use;
143 	unsigned char blksize_changed;
144 	unsigned char density_changed;
145 	unsigned char compression_changed;
146 	unsigned char drv_buffer;
147 	unsigned char density;
148 	unsigned char door_locked;
149 	unsigned char autorew_dev;   /* auto-rewind device */
150 	unsigned char rew_at_close;  /* rewind necessary at close */
151 	unsigned char inited;
152 	unsigned char cleaning_req;  /* cleaning requested? */
153 	int block_size;
154 	int min_block;
155 	int max_block;
156 	int recover_count;     /* From tape opening */
157 	int recover_reg;       /* From last status call */
158 
159 #if DEBUG
160 	unsigned char write_pending;
161 	int nbr_finished;
162 	int nbr_waits;
163 	int nbr_requests;
164 	int nbr_dio;
165 	int nbr_pages;
166 	int nbr_combinable;
167 	unsigned char last_cmnd[6];
168 	unsigned char last_sense[16];
169 #endif
170 	struct gendisk *disk;
171 	struct kref     kref;
172 };
173 
174 /* Bit masks for use_pf */
175 #define USE_PF      1
176 #define PF_TESTED   2
177 
178 /* Values of eof */
179 #define	ST_NOEOF	0
180 #define ST_FM_HIT       1
181 #define ST_FM           2
182 #define ST_EOM_OK       3
183 #define ST_EOM_ERROR	4
184 #define	ST_EOD_1        5
185 #define ST_EOD_2        6
186 #define ST_EOD		7
187 /* EOD hit while reading => ST_EOD_1 => return zero => ST_EOD_2 =>
188    return zero => ST_EOD, return ENOSPC */
189 /* When writing: ST_EOM_OK == early warning found, write OK
190 		 ST_EOD_1  == allow trying new write after early warning
191 		 ST_EOM_ERROR == early warning found, not able to write all */
192 
193 /* Values of rw */
194 #define	ST_IDLE		0
195 #define	ST_READING	1
196 #define	ST_WRITING	2
197 
198 /* Values of ready state */
199 #define ST_READY	0
200 #define ST_NOT_READY	1
201 #define ST_NO_TAPE	2
202 
203 /* Values for door lock state */
204 #define ST_UNLOCKED	0
205 #define ST_LOCKED_EXPLICIT 1
206 #define ST_LOCKED_AUTO  2
207 #define ST_LOCK_FAILS   3
208 
209 /* Positioning SCSI-commands for Tandberg, etc. drives */
210 #define	QFA_REQUEST_BLOCK	0x02
211 #define	QFA_SEEK_BLOCK		0x0c
212 
213 /* Setting the binary options */
214 #define ST_DONT_TOUCH  0
215 #define ST_NO          1
216 #define ST_YES         2
217 
218 #define EXTENDED_SENSE_START  18
219 
220 /* Masks for some conditions in the sense data */
221 #define SENSE_FMK   0x80
222 #define SENSE_EOM   0x40
223 #define SENSE_ILI   0x20
224 
225 #endif
226