xref: /openbmc/linux/drivers/scsi/sd.h (revision 82ced6fd)
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  * This is limited by the naming scheme enforced in sd_probe,
13  * add another character to it if you really need more disks.
14  */
15 #define SD_MAX_DISKS	(((26 * 26) + 26 + 1) * 26)
16 
17 /*
18  * Time out in seconds for disks and Magneto-opticals (which are slower).
19  */
20 #define SD_TIMEOUT		(30 * HZ)
21 #define SD_MOD_TIMEOUT		(75 * HZ)
22 
23 /*
24  * Number of allowed retries
25  */
26 #define SD_MAX_RETRIES		5
27 #define SD_PASSTHROUGH_RETRIES	1
28 
29 /*
30  * Size of the initial data buffer for mode and read capacity data
31  */
32 #define SD_BUF_SIZE		512
33 
34 /*
35  * Number of sectors at the end of the device to avoid multi-sector
36  * accesses to in the case of last_sector_bug
37  */
38 #define SD_LAST_BUGGY_SECTORS	8
39 
40 struct scsi_disk {
41 	struct scsi_driver *driver;	/* always &sd_template */
42 	struct scsi_device *device;
43 	struct device	dev;
44 	struct gendisk	*disk;
45 	unsigned int	openers;	/* protected by BKL for now, yuck */
46 	sector_t	capacity;	/* size in 512-byte sectors */
47 	u32		index;
48 	u8		media_present;
49 	u8		write_prot;
50 	u8		protection_type;/* Data Integrity Field */
51 	unsigned	previous_state : 1;
52 	unsigned	ATO : 1;	/* state of disk ATO bit */
53 	unsigned	WCE : 1;	/* state of disk WCE bit */
54 	unsigned	RCD : 1;	/* state of disk RCD bit, unused */
55 	unsigned	DPOFUA : 1;	/* state of disk DPOFUA bit */
56 	unsigned	first_scan : 1;
57 };
58 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
59 
60 static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
61 {
62 	return container_of(disk->private_data, struct scsi_disk, driver);
63 }
64 
65 #define sd_printk(prefix, sdsk, fmt, a...)				\
66         (sdsk)->disk ?							\
67 	sdev_printk(prefix, (sdsk)->device, "[%s] " fmt,		\
68 		    (sdsk)->disk->disk_name, ##a) :			\
69 	sdev_printk(prefix, (sdsk)->device, fmt, ##a)
70 
71 /*
72  * A DIF-capable target device can be formatted with different
73  * protection schemes.  Currently 0 through 3 are defined:
74  *
75  * Type 0 is regular (unprotected) I/O
76  *
77  * Type 1 defines the contents of the guard and reference tags
78  *
79  * Type 2 defines the contents of the guard and reference tags and
80  * uses 32-byte commands to seed the latter
81  *
82  * Type 3 defines the contents of the guard tag only
83  */
84 
85 enum sd_dif_target_protection_types {
86 	SD_DIF_TYPE0_PROTECTION = 0x0,
87 	SD_DIF_TYPE1_PROTECTION = 0x1,
88 	SD_DIF_TYPE2_PROTECTION = 0x2,
89 	SD_DIF_TYPE3_PROTECTION = 0x3,
90 };
91 
92 /*
93  * Data Integrity Field tuple.
94  */
95 struct sd_dif_tuple {
96        __be16 guard_tag;	/* Checksum */
97        __be16 app_tag;		/* Opaque storage */
98        __be32 ref_tag;		/* Target LBA or indirect LBA */
99 };
100 
101 #ifdef CONFIG_BLK_DEV_INTEGRITY
102 
103 extern void sd_dif_op(struct scsi_cmnd *, unsigned int, unsigned int, unsigned int);
104 extern void sd_dif_config_host(struct scsi_disk *);
105 extern int sd_dif_prepare(struct request *rq, sector_t, unsigned int);
106 extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
107 
108 #else /* CONFIG_BLK_DEV_INTEGRITY */
109 
110 static inline void sd_dif_op(struct scsi_cmnd *cmd, unsigned int a, unsigned int b, unsigned int c)
111 {
112 }
113 static inline void sd_dif_config_host(struct scsi_disk *disk)
114 {
115 }
116 static inline int sd_dif_prepare(struct request *rq, sector_t s, unsigned int a)
117 {
118 	return 0;
119 }
120 static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
121 {
122 }
123 
124 #endif /* CONFIG_BLK_DEV_INTEGRITY */
125 
126 #endif /* _SCSI_DISK_H */
127