LXR linux/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
  40enum {
  41        SD_EXT_CDB_SIZE = 32,   /* Extended CDB size */
  42        SD_MEMPOOL_SIZE = 2,    /* CDB pool size */
  43};
  44
  45struct scsi_disk {
  46        struct scsi_driver *driver;     /* always &sd_template */
  47        struct scsi_device *device;
  48        struct device   dev;
  49        struct gendisk  *disk;
  50        unsigned int    openers;        /* protected by BKL for now, yuck */
  51        sector_t        capacity;       /* size in 512-byte sectors */
  52        u32             index;
  53        unsigned short  hw_sector_size;
  54        u8              media_present;
  55        u8              write_prot;
  56        u8              protection_type;/* Data Integrity Field */
  57        unsigned        previous_state : 1;
  58        unsigned        ATO : 1;        /* state of disk ATO bit */
  59        unsigned        WCE : 1;        /* state of disk WCE bit */
  60        unsigned        RCD : 1;        /* state of disk RCD bit, unused */
  61        unsigned        DPOFUA : 1;     /* state of disk DPOFUA bit */
  62        unsigned        first_scan : 1;
  63};
  64#define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
  65
  66static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
  67{
  68        return container_of(disk->private_data, struct scsi_disk, driver);
  69}
  70
  71#define sd_printk(prefix, sdsk, fmt, a...)                              \
  72        (sdsk)->disk ?                                                  \
  73        sdev_printk(prefix, (sdsk)->device, "[%s] " fmt,                \
  74                    (sdsk)->disk->disk_name, ##a) :                     \
  75        sdev_printk(prefix, (sdsk)->device, fmt, ##a)
  76
  77/*
  78 * A DIF-capable target device can be formatted with different
  79 * protection schemes.  Currently 0 through 3 are defined:
  80 *
  81 * Type 0 is regular (unprotected) I/O
  82 *
  83 * Type 1 defines the contents of the guard and reference tags
  84 *
  85 * Type 2 defines the contents of the guard and reference tags and
  86 * uses 32-byte commands to seed the latter
  87 *
  88 * Type 3 defines the contents of the guard tag only
  89 */
  90
  91enum sd_dif_target_protection_types {
  92        SD_DIF_TYPE0_PROTECTION = 0x0,
  93        SD_DIF_TYPE1_PROTECTION = 0x1,
  94        SD_DIF_TYPE2_PROTECTION = 0x2,
  95        SD_DIF_TYPE3_PROTECTION = 0x3,
  96};
  97
  98/*
  99 * Data Integrity Field tuple.
 100 */
 101struct sd_dif_tuple {
 102       __be16 guard_tag;        /* Checksum */
 103       __be16 app_tag;          /* Opaque storage */
 104       __be32 ref_tag;          /* Target LBA or indirect LBA */
 105};
 106
 107#ifdef CONFIG_BLK_DEV_INTEGRITY
 108
 109extern void sd_dif_config_host(struct scsi_disk *);
 110extern int sd_dif_prepare(struct request *rq, sector_t, unsigned int);
 111extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
 112
 113#else /* CONFIG_BLK_DEV_INTEGRITY */
 114
 115static inline void sd_dif_config_host(struct scsi_disk *disk)
 116{
 117}
 118static inline int sd_dif_prepare(struct request *rq, sector_t s, unsigned int a)
 119{
 120        return 0;
 121}
 122static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
 123{
 124}
 125
 126#endif /* CONFIG_BLK_DEV_INTEGRITY */
 127
 128#endif /* _SCSI_DISK_H */
 129