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sd.h
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1 #ifndef _SCSI_DISK_H
2 #define _SCSI_DISK_H
3 
4 /*
5  * More than enough for everybody ;) The huge number of majors
6  * is a leftover from 16bit dev_t days, we don't really need that
7  * much numberspace.
8  */
9 #define SD_MAJORS 16
10 
11 /*
12  * Time out in seconds for disks and Magneto-opticals (which are slower).
13  */
14 #define SD_TIMEOUT (30 * HZ)
15 #define SD_MOD_TIMEOUT (75 * HZ)
16 #define SD_FLUSH_TIMEOUT (60 * HZ)
17 #define SD_WRITE_SAME_TIMEOUT (120 * HZ)
18 
19 /*
20  * Number of allowed retries
21  */
22 #define SD_MAX_RETRIES 5
23 #define SD_PASSTHROUGH_RETRIES 1
24 #define SD_MAX_MEDIUM_TIMEOUTS 2
25 
26 /*
27  * Size of the initial data buffer for mode and read capacity data
28  */
29 #define SD_BUF_SIZE 512
30 
31 /*
32  * Number of sectors at the end of the device to avoid multi-sector
33  * accesses to in the case of last_sector_bug
34  */
35 #define SD_LAST_BUGGY_SECTORS 8
36 
37 enum {
38  SD_EXT_CDB_SIZE = 32, /* Extended CDB size */
39  SD_MEMPOOL_SIZE = 2, /* CDB pool size */
40 };
41 
42 enum {
43  SD_MAX_WS10_BLOCKS = 0xffff,
44  SD_MAX_WS16_BLOCKS = 0x7fffff,
45 };
46 
47 enum {
48  SD_LBP_FULL = 0, /* Full logical block provisioning */
49  SD_LBP_UNMAP, /* Use UNMAP command */
50  SD_LBP_WS16, /* Use WRITE SAME(16) with UNMAP bit */
51  SD_LBP_WS10, /* Use WRITE SAME(10) with UNMAP bit */
52  SD_LBP_ZERO, /* Use WRITE SAME(10) with zero payload */
53  SD_LBP_DISABLE, /* Discard disabled due to failed cmd */
54 };
55 
56 struct scsi_disk {
57  struct scsi_driver *driver; /* always &sd_template */
58  struct scsi_device *device;
59  struct device dev;
60  struct gendisk *disk;
61  atomic_t openers;
62  sector_t capacity; /* size in 512-byte sectors */
63  u32 max_ws_blocks;
64  u32 max_unmap_blocks;
65  u32 unmap_granularity;
66  u32 unmap_alignment;
67  u32 index;
68  unsigned int physical_block_size;
69  unsigned int max_medium_access_timeouts;
70  unsigned int medium_access_timed_out;
71  u8 media_present;
72  u8 write_prot;
73  u8 protection_type;/* Data Integrity Field */
74  u8 provisioning_mode;
75  unsigned ATO : 1; /* state of disk ATO bit */
76  unsigned WCE : 1; /* state of disk WCE bit */
77  unsigned RCD : 1; /* state of disk RCD bit, unused */
78  unsigned DPOFUA : 1; /* state of disk DPOFUA bit */
79  unsigned first_scan : 1;
80  unsigned lbpme : 1;
81  unsigned lbprz : 1;
82  unsigned lbpu : 1;
83  unsigned lbpws : 1;
84  unsigned lbpws10 : 1;
85  unsigned lbpvpd : 1;
86  unsigned ws16 : 1;
87 };
88 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
89 
90 static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
91 {
92  return container_of(disk->private_data, struct scsi_disk, driver);
93 }
94 
95 #define sd_printk(prefix, sdsk, fmt, a...) \
96  (sdsk)->disk ? \
97  sdev_printk(prefix, (sdsk)->device, "[%s] " fmt, \
98  (sdsk)->disk->disk_name, ##a) : \
99  sdev_printk(prefix, (sdsk)->device, fmt, ##a)
100 
101 static inline int scsi_medium_access_command(struct scsi_cmnd *scmd)
102 {
103  switch (scmd->cmnd[0]) {
104  case READ_6:
105  case READ_10:
106  case READ_12:
107  case READ_16:
108  case SYNCHRONIZE_CACHE:
109  case VERIFY:
110  case VERIFY_12:
111  case VERIFY_16:
112  case WRITE_6:
113  case WRITE_10:
114  case WRITE_12:
115  case WRITE_16:
116  case WRITE_SAME:
117  case WRITE_SAME_16:
118  case UNMAP:
119  return 1;
120  case VARIABLE_LENGTH_CMD:
121  switch (scmd->cmnd[9]) {
122  case READ_32:
123  case VERIFY_32:
124  case WRITE_32:
125  case WRITE_SAME_32:
126  return 1;
127  }
128  }
129 
130  return 0;
131 }
132 
133 /*
134  * A DIF-capable target device can be formatted with different
135  * protection schemes. Currently 0 through 3 are defined:
136  *
137  * Type 0 is regular (unprotected) I/O
138  *
139  * Type 1 defines the contents of the guard and reference tags
140  *
141  * Type 2 defines the contents of the guard and reference tags and
142  * uses 32-byte commands to seed the latter
143  *
144  * Type 3 defines the contents of the guard tag only
145  */
146 
147 enum sd_dif_target_protection_types {
148  SD_DIF_TYPE0_PROTECTION = 0x0,
149  SD_DIF_TYPE1_PROTECTION = 0x1,
150  SD_DIF_TYPE2_PROTECTION = 0x2,
151  SD_DIF_TYPE3_PROTECTION = 0x3,
152 };
153 
154 /*
155  * Data Integrity Field tuple.
156  */
157 struct sd_dif_tuple {
158  __be16 guard_tag; /* Checksum */
159  __be16 app_tag; /* Opaque storage */
160  __be32 ref_tag; /* Target LBA or indirect LBA */
161 };
162 
163 #ifdef CONFIG_BLK_DEV_INTEGRITY
164 
165 extern void sd_dif_config_host(struct scsi_disk *);
166 extern void sd_dif_prepare(struct request *rq, sector_t, unsigned int);
167 extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
168 
169 #else /* CONFIG_BLK_DEV_INTEGRITY */
170 
171 static inline void sd_dif_config_host(struct scsi_disk *disk)
172 {
173 }
174 static inline int sd_dif_prepare(struct request *rq, sector_t s, unsigned int a)
175 {
176  return 0;
177 }
178 static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
179 {
180 }
181 
182 #endif /* CONFIG_BLK_DEV_INTEGRITY */
183 
184 #endif /* _SCSI_DISK_H */
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