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
  41 enum {
  42         SD_EXT_CDB_SIZE = 32,   /* Extended CDB size */
  43         SD_MEMPOOL_SIZE = 2,    /* CDB pool size */
  44 };
  45
  46 enum {
  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
  53 enum {
  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
  62 struct 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 512-byte sectors */
  69         u32             max_xfer_blocks;
  70         u32             max_ws_blocks;
  71         u32             max_unmap_blocks;
  72         u32             unmap_granularity;
  73         u32             unmap_alignment;
  74         u32             index;
  75         unsigned int    physical_block_size;
  76         unsigned int    max_medium_access_timeouts;
  77         unsigned int    medium_access_timed_out;
  78         u8              media_present;
  79         u8              write_prot;
  80         u8              protection_type;/* Data Integrity Field */
  81         u8              provisioning_mode;
  82         unsigned        ATO : 1;        /* state of disk ATO bit */
  83         unsigned        cache_override : 1; /* temp override of WCE,RCD */
  84         unsigned        WCE : 1;        /* state of disk WCE bit */
  85         unsigned        RCD : 1;        /* state of disk RCD bit, unused */
  86         unsigned        DPOFUA : 1;     /* state of disk DPOFUA bit */
  87         unsigned        first_scan : 1;
  88         unsigned        lbpme : 1;
  89         unsigned        lbprz : 1;
  90         unsigned        lbpu : 1;
  91         unsigned        lbpws : 1;
  92         unsigned        lbpws10 : 1;
  93         unsigned        lbpvpd : 1;
  94         unsigned        ws10 : 1;
  95         unsigned        ws16 : 1;
  96 };
  97 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
  98
  99 static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
 100 {
 101         return container_of(disk->private_data, struct scsi_disk, driver);
 102 }
 103
 104 #define sd_printk(prefix, sdsk, fmt, a...)                              \
 105         (sdsk)->disk ?                                                  \
 106               sdev_prefix_printk(prefix, (sdsk)->device,                \
 107                                  (sdsk)->disk->disk_name, fmt, ##a) :   \
 108               sdev_printk(prefix, (sdsk)->device, fmt, ##a)
 109
 110 #define sd_first_printk(prefix, sdsk, fmt, a...)                        \
 111         do {                                                            \
 112                 if ((sdkp)->first_scan)                                 \
 113                         sd_printk(prefix, sdsk, fmt, ##a);              \
 114         } while (0)
 115
 116 static inline int scsi_medium_access_command(struct scsi_cmnd *scmd)
 117 {
 118         switch (scmd->cmnd[0]) {
 119         case READ_6:
 120         case READ_10:
 121         case READ_12:
 122         case READ_16:
 123         case SYNCHRONIZE_CACHE:
 124         case VERIFY:
 125         case VERIFY_12:
 126         case VERIFY_16:
 127         case WRITE_6:
 128         case WRITE_10:
 129         case WRITE_12:
 130         case WRITE_16:
 131         case WRITE_SAME:
 132         case WRITE_SAME_16:
 133         case UNMAP:
 134                 return 1;
 135         case VARIABLE_LENGTH_CMD:
 136                 switch (scmd->cmnd[9]) {
 137                 case READ_32:
 138                 case VERIFY_32:
 139                 case WRITE_32:
 140                 case WRITE_SAME_32:
 141                         return 1;
 142                 }
 143         }
 144
 145         return 0;
 146 }
 147
 148 /*
 149  * A DIF-capable target device can be formatted with different
 150  * protection schemes.  Currently 0 through 3 are defined:
 151  *
 152  * Type 0 is regular (unprotected) I/O
 153  *
 154  * Type 1 defines the contents of the guard and reference tags
 155  *
 156  * Type 2 defines the contents of the guard and reference tags and
 157  * uses 32-byte commands to seed the latter
 158  *
 159  * Type 3 defines the contents of the guard tag only
 160  */
 161
 162 enum sd_dif_target_protection_types {
 163         SD_DIF_TYPE0_PROTECTION = 0x0,
 164         SD_DIF_TYPE1_PROTECTION = 0x1,
 165         SD_DIF_TYPE2_PROTECTION = 0x2,
 166         SD_DIF_TYPE3_PROTECTION = 0x3,
 167 };
 168
 169 /*
 170  * Look up the DIX operation based on whether the command is read or
 171  * write and whether dix and dif are enabled.
 172  */
 173 static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
 174 {
 175         /* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
 176         const unsigned int ops[] = {    /* wrt dix dif */
 177                 SCSI_PROT_NORMAL,       /*  0   0   0  */
 178                 SCSI_PROT_READ_STRIP,   /*  0   0   1  */
 179                 SCSI_PROT_READ_INSERT,  /*  0   1   0  */
 180                 SCSI_PROT_READ_PASS,    /*  0   1   1  */
 181                 SCSI_PROT_NORMAL,       /*  1   0   0  */
 182                 SCSI_PROT_WRITE_INSERT, /*  1   0   1  */
 183                 SCSI_PROT_WRITE_STRIP,  /*  1   1   0  */
 184                 SCSI_PROT_WRITE_PASS,   /*  1   1   1  */
 185         };
 186
 187         return ops[write << 2 | dix << 1 | dif];
 188 }
 189
 190 /*
 191  * Returns a mask of the protection flags that are valid for a given DIX
 192  * operation.
 193  */
 194 static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
 195 {
 196         const unsigned int flag_mask[] = {
 197                 [SCSI_PROT_NORMAL]              = 0,
 198
 199                 [SCSI_PROT_READ_STRIP]          = SCSI_PROT_TRANSFER_PI |
 200                                                   SCSI_PROT_GUARD_CHECK |
 201                                                   SCSI_PROT_REF_CHECK |
 202                                                   SCSI_PROT_REF_INCREMENT,
 203
 204                 [SCSI_PROT_READ_INSERT]         = SCSI_PROT_REF_INCREMENT |
 205                                                   SCSI_PROT_IP_CHECKSUM,
 206
 207                 [SCSI_PROT_READ_PASS]           = SCSI_PROT_TRANSFER_PI |
 208                                                   SCSI_PROT_GUARD_CHECK |
 209                                                   SCSI_PROT_REF_CHECK |
 210                                                   SCSI_PROT_REF_INCREMENT |
 211                                                   SCSI_PROT_IP_CHECKSUM,
 212
 213                 [SCSI_PROT_WRITE_INSERT]        = SCSI_PROT_TRANSFER_PI |
 214                                                   SCSI_PROT_REF_INCREMENT,
 215
 216                 [SCSI_PROT_WRITE_STRIP]         = SCSI_PROT_GUARD_CHECK |
 217                                                   SCSI_PROT_REF_CHECK |
 218                                                   SCSI_PROT_REF_INCREMENT |
 219                                                   SCSI_PROT_IP_CHECKSUM,
 220
 221                 [SCSI_PROT_WRITE_PASS]          = SCSI_PROT_TRANSFER_PI |
 222                                                   SCSI_PROT_GUARD_CHECK |
 223                                                   SCSI_PROT_REF_CHECK |
 224                                                   SCSI_PROT_REF_INCREMENT |
 225                                                   SCSI_PROT_IP_CHECKSUM,
 226         };
 227
 228         return flag_mask[prot_op];
 229 }
 230
 231 /*
 232  * Data Integrity Field tuple.
 233  */
 234 struct sd_dif_tuple {
 235        __be16 guard_tag;        /* Checksum */
 236        __be16 app_tag;          /* Opaque storage */
 237        __be32 ref_tag;          /* Target LBA or indirect LBA */
 238 };
 239
 240 #ifdef CONFIG_BLK_DEV_INTEGRITY
 241
 242 extern void sd_dif_config_host(struct scsi_disk *);
 243 extern void sd_dif_prepare(struct scsi_cmnd *scmd);
 244 extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
 245
 246 #else /* CONFIG_BLK_DEV_INTEGRITY */
 247
 248 static inline void sd_dif_config_host(struct scsi_disk *disk)
 249 {
 250 }
 251 static inline int sd_dif_prepare(struct scsi_cmnd *scmd)
 252 {
 253         return 0;
 254 }
 255 static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
 256 {
 257 }
 258
 259 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 260
 261 #endif /* _SCSI_DISK_H */