drivers/scsi/sd.h

   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 */