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 * 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/*
  17 * Flush timeout is a multiplier over the standard device timeout which is
  18 * user modifiable via sysfs but initially set to SD_TIMEOUT
  19 */
  20#define SD_FLUSH_TIMEOUT_MULTIPLIER     2
  21#define SD_WRITE_SAME_TIMEOUT   (120 * HZ)
  22
  23/*
  24 * Number of allowed retries
  25 */
  26#define SD_MAX_RETRIES          5
  27#define SD_PASSTHROUGH_RETRIES  1
  28#define SD_MAX_MEDIUM_TIMEOUTS  2
  29
  30/*
  31 * Size of the initial data buffer for mode and read capacity data
  32 */
  33#define SD_BUF_SIZE             512
  34
  35/*
  36 * Number of sectors at the end of the device to avoid multi-sector
  37 * accesses to in the case of last_sector_bug
  38 */
  39#define SD_LAST_BUGGY_SECTORS   8
  40
  41enum {
  42        SD_EXT_CDB_SIZE = 32,   /* Extended CDB size */
  43        SD_MEMPOOL_SIZE = 2,    /* CDB pool size */
  44};
  45
  46enum {
  47        SD_DEF_XFER_BLOCKS = 0xffff,
  48        SD_MAX_XFER_BLOCKS = 0xffffffff,
  49        SD_MAX_WS10_BLOCKS = 0xffff,
  50        SD_MAX_WS16_BLOCKS = 0x7fffff,
  51};
  52
  53enum {
  54        SD_LBP_FULL = 0,        /* Full logical block provisioning */
  55        SD_LBP_UNMAP,           /* Use UNMAP command */
  56        SD_LBP_WS16,            /* Use WRITE SAME(16) with UNMAP bit */
  57        SD_LBP_WS10,            /* Use WRITE SAME(10) with UNMAP bit */
  58        SD_LBP_ZERO,            /* Use WRITE SAME(10) with zero payload */
  59        SD_LBP_DISABLE,         /* Discard disabled due to failed cmd */
  60};
  61
  62struct scsi_disk {
  63        struct scsi_driver *driver;     /* always &sd_template */
  64        struct scsi_device *device;
  65        struct device   dev;
  66        struct gendisk  *disk;
  67        atomic_t        openers;
  68        sector_t        capacity;       /* size in logical blocks */
  69        u32             max_xfer_blocks;
  70        u32             opt_xfer_blocks;
  71        u32             max_ws_blocks;
  72        u32             max_unmap_blocks;
  73        u32             unmap_granularity;
  74        u32             unmap_alignment;
  75        u32             index;
  76        unsigned int    physical_block_size;
  77        unsigned int    max_medium_access_timeouts;
  78        unsigned int    medium_access_timed_out;
  79        u8              media_present;
  80        u8              write_prot;
  81        u8              protection_type;/* Data Integrity Field */
  82        u8              provisioning_mode;
  83        unsigned        ATO : 1;        /* state of disk ATO bit */
  84        unsigned        cache_override : 1; /* temp override of WCE,RCD */
  85        unsigned        WCE : 1;        /* state of disk WCE bit */
  86        unsigned        RCD : 1;        /* state of disk RCD bit, unused */
  87        unsigned        DPOFUA : 1;     /* state of disk DPOFUA bit */
  88        unsigned        first_scan : 1;
  89        unsigned        lbpme : 1;
  90        unsigned        lbprz : 1;
  91        unsigned        lbpu : 1;
  92        unsigned        lbpws : 1;
  93        unsigned        lbpws10 : 1;
  94        unsigned        lbpvpd : 1;
  95        unsigned        ws10 : 1;
  96        unsigned        ws16 : 1;
  97};
  98#define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
  99
 100static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
 101{
 102        return container_of(disk->private_data, struct scsi_disk, driver);
 103}
 104
 105#define sd_printk(prefix, sdsk, fmt, a...)                              \
 106        (sdsk)->disk ?                                                  \
 107              sdev_prefix_printk(prefix, (sdsk)->device,                \
 108                                 (sdsk)->disk->disk_name, fmt, ##a) :   \
 109              sdev_printk(prefix, (sdsk)->device, fmt, ##a)
 110
 111#define sd_first_printk(prefix, sdsk, fmt, a...)                        \
 112        do {                                                            \
 113                if ((sdkp)->first_scan)                                 \
 114                        sd_printk(prefix, sdsk, fmt, ##a);              \
 115        } while (0)
 116
 117static inline int scsi_medium_access_command(struct scsi_cmnd *scmd)
 118{
 119        switch (scmd->cmnd[0]) {
 120        case READ_6:
 121        case READ_10:
 122        case READ_12:
 123        case READ_16:
 124        case SYNCHRONIZE_CACHE:
 125        case VERIFY:
 126        case VERIFY_12:
 127        case VERIFY_16:
 128        case WRITE_6:
 129        case WRITE_10:
 130        case WRITE_12:
 131        case WRITE_16:
 132        case WRITE_SAME:
 133        case WRITE_SAME_16:
 134        case UNMAP:
 135                return 1;
 136        case VARIABLE_LENGTH_CMD:
 137                switch (scmd->cmnd[9]) {
 138                case READ_32:
 139                case VERIFY_32:
 140                case WRITE_32:
 141                case WRITE_SAME_32:
 142                        return 1;
 143                }
 144        }
 145
 146        return 0;
 147}
 148
 149static inline sector_t logical_to_sectors(struct scsi_device *sdev, sector_t blocks)
 150{
 151        return blocks << (ilog2(sdev->sector_size) - 9);
 152}
 153
 154static inline unsigned int logical_to_bytes(struct scsi_device *sdev, sector_t blocks)
 155{
 156        return blocks * sdev->sector_size;
 157}
 158
 159/*
 160 * Look up the DIX operation based on whether the command is read or
 161 * write and whether dix and dif are enabled.
 162 */
 163static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
 164{
 165        /* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
 166        const unsigned int ops[] = {    /* wrt dix dif */
 167                SCSI_PROT_NORMAL,       /*  0   0   0  */
 168                SCSI_PROT_READ_STRIP,   /*  0   0   1  */
 169                SCSI_PROT_READ_INSERT,  /*  0   1   0  */
 170                SCSI_PROT_READ_PASS,    /*  0   1   1  */
 171                SCSI_PROT_NORMAL,       /*  1   0   0  */
 172                SCSI_PROT_WRITE_INSERT, /*  1   0   1  */
 173                SCSI_PROT_WRITE_STRIP,  /*  1   1   0  */
 174                SCSI_PROT_WRITE_PASS,   /*  1   1   1  */
 175        };
 176
 177        return ops[write << 2 | dix << 1 | dif];
 178}
 179
 180/*
 181 * Returns a mask of the protection flags that are valid for a given DIX
 182 * operation.
 183 */
 184static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
 185{
 186        const unsigned int flag_mask[] = {
 187                [SCSI_PROT_NORMAL]              = 0,
 188
 189                [SCSI_PROT_READ_STRIP]          = SCSI_PROT_TRANSFER_PI |
 190                                                  SCSI_PROT_GUARD_CHECK |
 191                                                  SCSI_PROT_REF_CHECK |
 192                                                  SCSI_PROT_REF_INCREMENT,
 193
 194                [SCSI_PROT_READ_INSERT]         = SCSI_PROT_REF_INCREMENT |
 195                                                  SCSI_PROT_IP_CHECKSUM,
 196
 197                [SCSI_PROT_READ_PASS]           = SCSI_PROT_TRANSFER_PI |
 198                                                  SCSI_PROT_GUARD_CHECK |
 199                                                  SCSI_PROT_REF_CHECK |
 200                                                  SCSI_PROT_REF_INCREMENT |
 201                                                  SCSI_PROT_IP_CHECKSUM,
 202
 203                [SCSI_PROT_WRITE_INSERT]        = SCSI_PROT_TRANSFER_PI |
 204                                                  SCSI_PROT_REF_INCREMENT,
 205
 206                [SCSI_PROT_WRITE_STRIP]         = SCSI_PROT_GUARD_CHECK |
 207                                                  SCSI_PROT_REF_CHECK |
 208                                                  SCSI_PROT_REF_INCREMENT |
 209                                                  SCSI_PROT_IP_CHECKSUM,
 210
 211                [SCSI_PROT_WRITE_PASS]          = SCSI_PROT_TRANSFER_PI |
 212                                                  SCSI_PROT_GUARD_CHECK |
 213                                                  SCSI_PROT_REF_CHECK |
 214                                                  SCSI_PROT_REF_INCREMENT |
 215                                                  SCSI_PROT_IP_CHECKSUM,
 216        };
 217
 218        return flag_mask[prot_op];
 219}
 220
 221#ifdef CONFIG_BLK_DEV_INTEGRITY
 222
 223extern void sd_dif_config_host(struct scsi_disk *);
 224extern void sd_dif_prepare(struct scsi_cmnd *scmd);
 225extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
 226
 227#else /* CONFIG_BLK_DEV_INTEGRITY */
 228
 229static inline void sd_dif_config_host(struct scsi_disk *disk)
 230{
 231}
 232static inline int sd_dif_prepare(struct scsi_cmnd *scmd)
 233{
 234        return 0;
 235}
 236static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
 237{
 238}
 239
 240#endif /* CONFIG_BLK_DEV_INTEGRITY */
 241
 242#endif /* _SCSI_DISK_H */
 243