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 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
 100 static 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
 117 static 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
 149 static inline sector_t logical_to_sectors(struct scsi_device *sdev, sector_t blocks)
 150 {
 151         return blocks << (ilog2(sdev->sector_size) - 9);
 152 }
 153
 154 static inline unsigned int logical_to_bytes(struct scsi_device *sdev, sector_t blocks)
 155 {
 156         return blocks * sdev->sector_size;
 157 }
 158
 159 /*
 160  * A DIF-capable target device can be formatted with different
 161  * protection schemes.  Currently 0 through 3 are defined:
 162  *
 163  * Type 0 is regular (unprotected) I/O
 164  *
 165  * Type 1 defines the contents of the guard and reference tags
 166  *
 167  * Type 2 defines the contents of the guard and reference tags and
 168  * uses 32-byte commands to seed the latter
 169  *
 170  * Type 3 defines the contents of the guard tag only
 171  */
 172
 173 enum sd_dif_target_protection_types {
 174         SD_DIF_TYPE0_PROTECTION = 0x0,
 175         SD_DIF_TYPE1_PROTECTION = 0x1,
 176         SD_DIF_TYPE2_PROTECTION = 0x2,
 177         SD_DIF_TYPE3_PROTECTION = 0x3,
 178 };
 179
 180 /*
 181  * Look up the DIX operation based on whether the command is read or
 182  * write and whether dix and dif are enabled.
 183  */
 184 static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
 185 {
 186         /* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
 187         const unsigned int ops[] = {    /* wrt dix dif */
 188                 SCSI_PROT_NORMAL,       /*  0   0   0  */
 189                 SCSI_PROT_READ_STRIP,   /*  0   0   1  */
 190                 SCSI_PROT_READ_INSERT,  /*  0   1   0  */
 191                 SCSI_PROT_READ_PASS,    /*  0   1   1  */
 192                 SCSI_PROT_NORMAL,       /*  1   0   0  */
 193                 SCSI_PROT_WRITE_INSERT, /*  1   0   1  */
 194                 SCSI_PROT_WRITE_STRIP,  /*  1   1   0  */
 195                 SCSI_PROT_WRITE_PASS,   /*  1   1   1  */
 196         };
 197
 198         return ops[write << 2 | dix << 1 | dif];
 199 }
 200
 201 /*
 202  * Returns a mask of the protection flags that are valid for a given DIX
 203  * operation.
 204  */
 205 static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
 206 {
 207         const unsigned int flag_mask[] = {
 208                 [SCSI_PROT_NORMAL]              = 0,
 209
 210                 [SCSI_PROT_READ_STRIP]          = SCSI_PROT_TRANSFER_PI |
 211                                                   SCSI_PROT_GUARD_CHECK |
 212                                                   SCSI_PROT_REF_CHECK |
 213                                                   SCSI_PROT_REF_INCREMENT,
 214
 215                 [SCSI_PROT_READ_INSERT]         = SCSI_PROT_REF_INCREMENT |
 216                                                   SCSI_PROT_IP_CHECKSUM,
 217
 218                 [SCSI_PROT_READ_PASS]           = SCSI_PROT_TRANSFER_PI |
 219                                                   SCSI_PROT_GUARD_CHECK |
 220                                                   SCSI_PROT_REF_CHECK |
 221                                                   SCSI_PROT_REF_INCREMENT |
 222                                                   SCSI_PROT_IP_CHECKSUM,
 223
 224                 [SCSI_PROT_WRITE_INSERT]        = SCSI_PROT_TRANSFER_PI |
 225                                                   SCSI_PROT_REF_INCREMENT,
 226
 227                 [SCSI_PROT_WRITE_STRIP]         = SCSI_PROT_GUARD_CHECK |
 228                                                   SCSI_PROT_REF_CHECK |
 229                                                   SCSI_PROT_REF_INCREMENT |
 230                                                   SCSI_PROT_IP_CHECKSUM,
 231
 232                 [SCSI_PROT_WRITE_PASS]          = SCSI_PROT_TRANSFER_PI |
 233                                                   SCSI_PROT_GUARD_CHECK |
 234                                                   SCSI_PROT_REF_CHECK |
 235                                                   SCSI_PROT_REF_INCREMENT |
 236                                                   SCSI_PROT_IP_CHECKSUM,
 237         };
 238
 239         return flag_mask[prot_op];
 240 }
 241
 242 /*
 243  * Data Integrity Field tuple.
 244  */
 245 struct sd_dif_tuple {
 246        __be16 guard_tag;        /* Checksum */
 247        __be16 app_tag;          /* Opaque storage */
 248        __be32 ref_tag;          /* Target LBA or indirect LBA */
 249 };
 250
 251 #ifdef CONFIG_BLK_DEV_INTEGRITY
 252
 253 extern void sd_dif_config_host(struct scsi_disk *);
 254 extern void sd_dif_prepare(struct scsi_cmnd *scmd);
 255 extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
 256
 257 #else /* CONFIG_BLK_DEV_INTEGRITY */
 258
 259 static inline void sd_dif_config_host(struct scsi_disk *disk)
 260 {
 261 }
 262 static inline int sd_dif_prepare(struct scsi_cmnd *scmd)
 263 {
 264         return 0;
 265 }
 266 static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
 267 {
 268 }
 269
 270 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 271
 272 #endif /* _SCSI_DISK_H */