include/blk.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * (C) Copyright 2000-2004
   4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   5  */
   6
   7 #ifndef BLK_H
   8 #define BLK_H
   9
  10 #include <efi.h>
  11
  12 #ifdef CONFIG_SYS_64BIT_LBA
  13 typedef uint64_t lbaint_t;
  14 #define LBAFlength "ll"
  15 #else
  16 typedef ulong lbaint_t;
  17 #define LBAFlength "l"
  18 #endif
  19 #define LBAF "%" LBAFlength "x"
  20 #define LBAFU "%" LBAFlength "u"
  21
  22 /* Interface types: */
  23 enum if_type {
  24         IF_TYPE_UNKNOWN = 0,
  25         IF_TYPE_IDE,
  26         IF_TYPE_SCSI,
  27         IF_TYPE_ATAPI,
  28         IF_TYPE_USB,
  29         IF_TYPE_DOC,
  30         IF_TYPE_MMC,
  31         IF_TYPE_SD,
  32         IF_TYPE_SATA,
  33         IF_TYPE_HOST,
  34         IF_TYPE_NVME,
  35         IF_TYPE_EFI,
  36         IF_TYPE_VIRTIO,
  37
  38         IF_TYPE_COUNT,                  /* Number of interface types */
  39 };
  40
  41 #define BLK_VEN_SIZE            40
  42 #define BLK_PRD_SIZE            20
  43 #define BLK_REV_SIZE            8
  44
  45 /*
  46  * Identifies the partition table type (ie. MBR vs GPT GUID) signature
  47  */
  48 enum sig_type {
  49         SIG_TYPE_NONE,
  50         SIG_TYPE_MBR,
  51         SIG_TYPE_GUID,
  52
  53         SIG_TYPE_COUNT                  /* Number of signature types */
  54 };
  55
  56 /*
  57  * With driver model (CONFIG_BLK) this is uclass platform data, accessible
  58  * with dev_get_uclass_platdata(dev)
  59  */
  60 struct blk_desc {
  61         /*
  62          * TODO: With driver model we should be able to use the parent
  63          * device's uclass instead.
  64          */
  65         enum if_type    if_type;        /* type of the interface */
  66         int             devnum;         /* device number */
  67         unsigned char   part_type;      /* partition type */
  68         unsigned char   target;         /* target SCSI ID */
  69         unsigned char   lun;            /* target LUN */
  70         unsigned char   hwpart;         /* HW partition, e.g. for eMMC */
  71         unsigned char   type;           /* device type */
  72         unsigned char   removable;      /* removable device */
  73 #ifdef CONFIG_LBA48
  74         /* device can use 48bit addr (ATA/ATAPI v7) */
  75         unsigned char   lba48;
  76 #endif
  77         lbaint_t        lba;            /* number of blocks */
  78         unsigned long   blksz;          /* block size */
  79         int             log2blksz;      /* for convenience: log2(blksz) */
  80         char            vendor[BLK_VEN_SIZE + 1]; /* device vendor string */
  81         char            product[BLK_PRD_SIZE + 1]; /* device product number */
  82         char            revision[BLK_REV_SIZE + 1]; /* firmware revision */
  83         enum sig_type   sig_type;       /* Partition table signature type */
  84         union {
  85                 uint32_t mbr_sig;       /* MBR integer signature */
  86                 efi_guid_t guid_sig;    /* GPT GUID Signature */
  87         };
  88 #if CONFIG_IS_ENABLED(BLK)
  89         /*
  90          * For now we have a few functions which take struct blk_desc as a
  91          * parameter. This field allows them to look up the associated
  92          * device. Once these functions are removed we can drop this field.
  93          */
  94         struct udevice *bdev;
  95 #else
  96         unsigned long   (*block_read)(struct blk_desc *block_dev,
  97                                       lbaint_t start,
  98                                       lbaint_t blkcnt,
  99                                       void *buffer);
 100         unsigned long   (*block_write)(struct blk_desc *block_dev,
 101                                        lbaint_t start,
 102                                        lbaint_t blkcnt,
 103                                        const void *buffer);
 104         unsigned long   (*block_erase)(struct blk_desc *block_dev,
 105                                        lbaint_t start,
 106                                        lbaint_t blkcnt);
 107         void            *priv;          /* driver private struct pointer */
 108 #endif
 109 };
 110
 111 #define BLOCK_CNT(size, blk_desc) (PAD_COUNT(size, blk_desc->blksz))
 112 #define PAD_TO_BLOCKSIZE(size, blk_desc) \
 113         (PAD_SIZE(size, blk_desc->blksz))
 114
 115 #if CONFIG_IS_ENABLED(BLOCK_CACHE)
 116 /**
 117  * blkcache_read() - attempt to read a set of blocks from cache
 118  *
 119  * @param iftype - IF_TYPE_x for type of device
 120  * @param dev - device index of particular type
 121  * @param start - starting block number
 122  * @param blkcnt - number of blocks to read
 123  * @param blksz - size in bytes of each block
 124  * @param buf - buffer to contain cached data
 125  *
 126  * @return - '1' if block returned from cache, '0' otherwise.
 127  */
 128 int blkcache_read(int iftype, int dev,
 129                   lbaint_t start, lbaint_t blkcnt,
 130                   unsigned long blksz, void *buffer);
 131
 132 /**
 133  * blkcache_fill() - make data read from a block device available
 134  * to the block cache
 135  *
 136  * @param iftype - IF_TYPE_x for type of device
 137  * @param dev - device index of particular type
 138  * @param start - starting block number
 139  * @param blkcnt - number of blocks available
 140  * @param blksz - size in bytes of each block
 141  * @param buf - buffer containing data to cache
 142  *
 143  */
 144 void blkcache_fill(int iftype, int dev,
 145                    lbaint_t start, lbaint_t blkcnt,
 146                    unsigned long blksz, void const *buffer);
 147
 148 /**
 149  * blkcache_invalidate() - discard the cache for a set of blocks
 150  * because of a write or device (re)initialization.
 151  *
 152  * @param iftype - IF_TYPE_x for type of device
 153  * @param dev - device index of particular type
 154  */
 155 void blkcache_invalidate(int iftype, int dev);
 156
 157 /**
 158  * blkcache_configure() - configure block cache
 159  *
 160  * @param blocks - maximum blocks per entry
 161  * @param entries - maximum entries in cache
 162  */
 163 void blkcache_configure(unsigned blocks, unsigned entries);
 164
 165 /*
 166  * statistics of the block cache
 167  */
 168 struct block_cache_stats {
 169         unsigned hits;
 170         unsigned misses;
 171         unsigned entries; /* current entry count */
 172         unsigned max_blocks_per_entry;
 173         unsigned max_entries;
 174 };
 175
 176 /**
 177  * get_blkcache_stats() - return statistics and reset
 178  *
 179  * @param stats - statistics are copied here
 180  */
 181 void blkcache_stats(struct block_cache_stats *stats);
 182
 183 #else
 184
 185 static inline int blkcache_read(int iftype, int dev,
 186                                 lbaint_t start, lbaint_t blkcnt,
 187                                 unsigned long blksz, void *buffer)
 188 {
 189         return 0;
 190 }
 191
 192 static inline void blkcache_fill(int iftype, int dev,
 193                                  lbaint_t start, lbaint_t blkcnt,
 194                                  unsigned long blksz, void const *buffer) {}
 195
 196 static inline void blkcache_invalidate(int iftype, int dev) {}
 197
 198 #endif
 199
 200 #if CONFIG_IS_ENABLED(BLK)
 201 struct udevice;
 202
 203 /* Operations on block devices */
 204 struct blk_ops {
 205         /**
 206          * read() - read from a block device
 207          *
 208          * @dev:        Device to read from
 209          * @start:      Start block number to read (0=first)
 210          * @blkcnt:     Number of blocks to read
 211          * @buffer:     Destination buffer for data read
 212          * @return number of blocks read, or -ve error number (see the
 213          * IS_ERR_VALUE() macro
 214          */
 215         unsigned long (*read)(struct udevice *dev, lbaint_t start,
 216                               lbaint_t blkcnt, void *buffer);
 217
 218         /**
 219          * write() - write to a block device
 220          *
 221          * @dev:        Device to write to
 222          * @start:      Start block number to write (0=first)
 223          * @blkcnt:     Number of blocks to write
 224          * @buffer:     Source buffer for data to write
 225          * @return number of blocks written, or -ve error number (see the
 226          * IS_ERR_VALUE() macro
 227          */
 228         unsigned long (*write)(struct udevice *dev, lbaint_t start,
 229                                lbaint_t blkcnt, const void *buffer);
 230
 231         /**
 232          * erase() - erase a section of a block device
 233          *
 234          * @dev:        Device to (partially) erase
 235          * @start:      Start block number to erase (0=first)
 236          * @blkcnt:     Number of blocks to erase
 237          * @return number of blocks erased, or -ve error number (see the
 238          * IS_ERR_VALUE() macro
 239          */
 240         unsigned long (*erase)(struct udevice *dev, lbaint_t start,
 241                                lbaint_t blkcnt);
 242
 243         /**
 244          * select_hwpart() - select a particular hardware partition
 245          *
 246          * Some devices (e.g. MMC) can support partitioning at the hardware
 247          * level. This is quite separate from the normal idea of
 248          * software-based partitions. MMC hardware partitions must be
 249          * explicitly selected. Once selected only the region of the device
 250          * covered by that partition is accessible.
 251          *
 252          * The MMC standard provides for two boot partitions (numbered 1 and 2),
 253          * rpmb (3), and up to 4 addition general-purpose partitions (4-7).
 254          *
 255          * @desc:       Block device to update
 256          * @hwpart:     Hardware partition number to select. 0 means the raw
 257          *              device, 1 is the first partition, 2 is the second, etc.
 258          * @return 0 if OK, -ve on error
 259          */
 260         int (*select_hwpart)(struct udevice *dev, int hwpart);
 261 };
 262
 263 #define blk_get_ops(dev)        ((struct blk_ops *)(dev)->driver->ops)
 264
 265 /*
 266  * These functions should take struct udevice instead of struct blk_desc,
 267  * but this is convenient for migration to driver model. Add a 'd' prefix
 268  * to the function operations, so that blk_read(), etc. can be reserved for
 269  * functions with the correct arguments.
 270  */
 271 unsigned long blk_dread(struct blk_desc *block_dev, lbaint_t start,
 272                         lbaint_t blkcnt, void *buffer);
 273 unsigned long blk_dwrite(struct blk_desc *block_dev, lbaint_t start,
 274                          lbaint_t blkcnt, const void *buffer);
 275 unsigned long blk_derase(struct blk_desc *block_dev, lbaint_t start,
 276                          lbaint_t blkcnt);
 277
 278 /**
 279  * blk_find_device() - Find a block device
 280  *
 281  * This function does not activate the device. The device will be returned
 282  * whether or not it is activated.
 283  *
 284  * @if_type:    Interface type (enum if_type_t)
 285  * @devnum:     Device number (specific to each interface type)
 286  * @devp:       the device, if found
 287  * @return 0 if found, -ENODEV if no device found, or other -ve error value
 288  */
 289 int blk_find_device(int if_type, int devnum, struct udevice **devp);
 290
 291 /**
 292  * blk_get_device() - Find and probe a block device ready for use
 293  *
 294  * @if_type:    Interface type (enum if_type_t)
 295  * @devnum:     Device number (specific to each interface type)
 296  * @devp:       the device, if found
 297  * @return 0 if found, -ENODEV if no device found, or other -ve error value
 298  */
 299 int blk_get_device(int if_type, int devnum, struct udevice **devp);
 300
 301 /**
 302  * blk_first_device() - Find the first device for a given interface
 303  *
 304  * The device is probed ready for use
 305  *
 306  * @devnum:     Device number (specific to each interface type)
 307  * @devp:       the device, if found
 308  * @return 0 if found, -ENODEV if no device, or other -ve error value
 309  */
 310 int blk_first_device(int if_type, struct udevice **devp);
 311
 312 /**
 313  * blk_next_device() - Find the next device for a given interface
 314  *
 315  * This can be called repeatedly after blk_first_device() to iterate through
 316  * all devices of the given interface type.
 317  *
 318  * The device is probed ready for use
 319  *
 320  * @devp:       On entry, the previous device returned. On exit, the next
 321  *              device, if found
 322  * @return 0 if found, -ENODEV if no device, or other -ve error value
 323  */
 324 int blk_next_device(struct udevice **devp);
 325
 326 /**
 327  * blk_create_device() - Create a new block device
 328  *
 329  * @parent:     Parent of the new device
 330  * @drv_name:   Driver name to use for the block device
 331  * @name:       Name for the device
 332  * @if_type:    Interface type (enum if_type_t)
 333  * @devnum:     Device number, specific to the interface type, or -1 to
 334  *              allocate the next available number
 335  * @blksz:      Block size of the device in bytes (typically 512)
 336  * @lba:        Total number of blocks of the device
 337  * @devp:       the new device (which has not been probed)
 338  */
 339 int blk_create_device(struct udevice *parent, const char *drv_name,
 340                       const char *name, int if_type, int devnum, int blksz,
 341                       lbaint_t lba, struct udevice **devp);
 342
 343 /**
 344  * blk_create_devicef() - Create a new named block device
 345  *
 346  * @parent:     Parent of the new device
 347  * @drv_name:   Driver name to use for the block device
 348  * @name:       Name for the device (parent name is prepended)
 349  * @if_type:    Interface type (enum if_type_t)
 350  * @devnum:     Device number, specific to the interface type, or -1 to
 351  *              allocate the next available number
 352  * @blksz:      Block size of the device in bytes (typically 512)
 353  * @lba:        Total number of blocks of the device
 354  * @devp:       the new device (which has not been probed)
 355  */
 356 int blk_create_devicef(struct udevice *parent, const char *drv_name,
 357                        const char *name, int if_type, int devnum, int blksz,
 358                        lbaint_t lba, struct udevice **devp);
 359
 360 /**
 361  * blk_unbind_all() - Unbind all device of the given interface type
 362  *
 363  * The devices are removed and then unbound.
 364  *
 365  * @if_type:    Interface type to unbind
 366  * @return 0 if OK, -ve on error
 367  */
 368 int blk_unbind_all(int if_type);
 369
 370 /**
 371  * blk_find_max_devnum() - find the maximum device number for an interface type
 372  *
 373  * Finds the last allocated device number for an interface type @if_type. The
 374  * next number is safe to use for a newly allocated device.
 375  *
 376  * @if_type:    Interface type to scan
 377  * @return maximum device number found, or -ENODEV if none, or other -ve on
 378  * error
 379  */
 380 int blk_find_max_devnum(enum if_type if_type);
 381
 382 /**
 383  * blk_next_free_devnum() - get the next device number for an interface type
 384  *
 385  * Finds the next number that is safe to use for a newly allocated device for
 386  * an interface type @if_type.
 387  *
 388  * @if_type:    Interface type to scan
 389  * @return next device number safe to use, or -ve on error
 390  */
 391 int blk_next_free_devnum(enum if_type if_type);
 392
 393 /**
 394  * blk_select_hwpart() - select a hardware partition
 395  *
 396  * Select a hardware partition if the device supports it (typically MMC does)
 397  *
 398  * @dev:        Device to update
 399  * @hwpart:     Partition number to select
 400  * @return 0 if OK, -ve on error
 401  */
 402 int blk_select_hwpart(struct udevice *dev, int hwpart);
 403
 404 /**
 405  * blk_get_from_parent() - obtain a block device by looking up its parent
 406  *
 407  * All devices with
 408  */
 409 int blk_get_from_parent(struct udevice *parent, struct udevice **devp);
 410
 411 /**
 412  * blk_get_by_device() - Get the block device descriptor for the given device
 413  * @dev:        Instance of a storage device
 414  *
 415  * Return: With block device descriptor on success , NULL if there is no such
 416  *         block device.
 417  */
 418 struct blk_desc *blk_get_by_device(struct udevice *dev);
 419
 420 #else
 421 #include <errno.h>
 422 /*
 423  * These functions should take struct udevice instead of struct blk_desc,
 424  * but this is convenient for migration to driver model. Add a 'd' prefix
 425  * to the function operations, so that blk_read(), etc. can be reserved for
 426  * functions with the correct arguments.
 427  */
 428 static inline ulong blk_dread(struct blk_desc *block_dev, lbaint_t start,
 429                               lbaint_t blkcnt, void *buffer)
 430 {
 431         ulong blks_read;
 432         if (blkcache_read(block_dev->if_type, block_dev->devnum,
 433                           start, blkcnt, block_dev->blksz, buffer))
 434                 return blkcnt;
 435
 436         /*
 437          * We could check if block_read is NULL and return -ENOSYS. But this
 438          * bloats the code slightly (cause some board to fail to build), and
 439          * it would be an error to try an operation that does not exist.
 440          */
 441         blks_read = block_dev->block_read(block_dev, start, blkcnt, buffer);
 442         if (blks_read == blkcnt)
 443                 blkcache_fill(block_dev->if_type, block_dev->devnum,
 444                               start, blkcnt, block_dev->blksz, buffer);
 445
 446         return blks_read;
 447 }
 448
 449 static inline ulong blk_dwrite(struct blk_desc *block_dev, lbaint_t start,
 450                                lbaint_t blkcnt, const void *buffer)
 451 {
 452         blkcache_invalidate(block_dev->if_type, block_dev->devnum);
 453         return block_dev->block_write(block_dev, start, blkcnt, buffer);
 454 }
 455
 456 static inline ulong blk_derase(struct blk_desc *block_dev, lbaint_t start,
 457                                lbaint_t blkcnt)
 458 {
 459         blkcache_invalidate(block_dev->if_type, block_dev->devnum);
 460         return block_dev->block_erase(block_dev, start, blkcnt);
 461 }
 462
 463 /**
 464  * struct blk_driver - Driver for block interface types
 465  *
 466  * This provides access to the block devices for each interface type. One
 467  * driver should be provided using U_BOOT_LEGACY_BLK() for each interface
 468  * type that is to be supported.
 469  *
 470  * @if_typename:        Interface type name
 471  * @if_type:            Interface type
 472  * @max_devs:           Maximum number of devices supported
 473  * @desc:               Pointer to list of devices for this interface type,
 474  *                      or NULL to use @get_dev() instead
 475  */
 476 struct blk_driver {
 477         const char *if_typename;
 478         enum if_type if_type;
 479         int max_devs;
 480         struct blk_desc *desc;
 481         /**
 482          * get_dev() - get a pointer to a block device given its number
 483          *
 484          * Each interface allocates its own devices and typically
 485          * struct blk_desc is contained with the interface's data structure.
 486          * There is no global numbering for block devices. This method allows
 487          * the device for an interface type to be obtained when @desc is NULL.
 488          *
 489          * @devnum:     Device number (0 for first device on that interface,
 490          *              1 for second, etc.
 491          * @descp:      Returns pointer to the block device on success
 492          * @return 0 if OK, -ve on error
 493          */
 494         int (*get_dev)(int devnum, struct blk_desc **descp);
 495
 496         /**
 497          * select_hwpart() - Select a hardware partition
 498          *
 499          * Some devices (e.g. MMC) can support partitioning at the hardware
 500          * level. This is quite separate from the normal idea of
 501          * software-based partitions. MMC hardware partitions must be
 502          * explicitly selected. Once selected only the region of the device
 503          * covered by that partition is accessible.
 504          *
 505          * The MMC standard provides for two boot partitions (numbered 1 and 2),
 506          * rpmb (3), and up to 4 addition general-purpose partitions (4-7).
 507          * Partition 0 is the main user-data partition.
 508          *
 509          * @desc:       Block device descriptor
 510          * @hwpart:     Hardware partition number to select. 0 means the main
 511          *              user-data partition, 1 is the first partition, 2 is
 512          *              the second, etc.
 513          * @return 0 if OK, other value for an error
 514          */
 515         int (*select_hwpart)(struct blk_desc *desc, int hwpart);
 516 };
 517
 518 /*
 519  * Declare a new U-Boot legacy block driver. New drivers should use driver
 520  * model (UCLASS_BLK).
 521  */
 522 #define U_BOOT_LEGACY_BLK(__name)                                       \
 523         ll_entry_declare(struct blk_driver, __name, blk_driver)
 524
 525 struct blk_driver *blk_driver_lookup_type(int if_type);
 526
 527 #endif /* !CONFIG_BLK */
 528
 529 /**
 530  * blk_get_devnum_by_typename() - Get a block device by type and number
 531  *
 532  * This looks through the available block devices of the given type, returning
 533  * the one with the given @devnum.
 534  *
 535  * @if_type:    Block device type
 536  * @devnum:     Device number
 537  * @return point to block device descriptor, or NULL if not found
 538  */
 539 struct blk_desc *blk_get_devnum_by_type(enum if_type if_type, int devnum);
 540
 541 /**
 542  * blk_get_devnum_by_type() - Get a block device by type name, and number
 543  *
 544  * This looks up the block device type based on @if_typename, then calls
 545  * blk_get_devnum_by_type().
 546  *
 547  * @if_typename:        Block device type name
 548  * @devnum:             Device number
 549  * @return point to block device descriptor, or NULL if not found
 550  */
 551 struct blk_desc *blk_get_devnum_by_typename(const char *if_typename,
 552                                             int devnum);
 553
 554 /**
 555  * blk_dselect_hwpart() - select a hardware partition
 556  *
 557  * This selects a hardware partition (such as is supported by MMC). The block
 558  * device size may change as this effectively points the block device to a
 559  * partition at the hardware level. See the select_hwpart() method above.
 560  *
 561  * @desc:       Block device descriptor for the device to select
 562  * @hwpart:     Partition number to select
 563  * @return 0 if OK, -ve on error
 564  */
 565 int blk_dselect_hwpart(struct blk_desc *desc, int hwpart);
 566
 567 /**
 568  * blk_list_part() - list the partitions for block devices of a given type
 569  *
 570  * This looks up the partition type for each block device of type @if_type,
 571  * then displays a list of partitions.
 572  *
 573  * @if_type:    Block device type
 574  * @return 0 if OK, -ENODEV if there is none of that type
 575  */
 576 int blk_list_part(enum if_type if_type);
 577
 578 /**
 579  * blk_list_devices() - list the block devices of a given type
 580  *
 581  * This lists each block device of the type @if_type, showing the capacity
 582  * as well as type-specific information.
 583  *
 584  * @if_type:    Block device type
 585  */
 586 void blk_list_devices(enum if_type if_type);
 587
 588 /**
 589  * blk_show_device() - show information about a given block device
 590  *
 591  * This shows the block device capacity as well as type-specific information.
 592  *
 593  * @if_type:    Block device type
 594  * @devnum:     Device number
 595  * @return 0 if OK, -ENODEV for invalid device number
 596  */
 597 int blk_show_device(enum if_type if_type, int devnum);
 598
 599 /**
 600  * blk_print_device_num() - show information about a given block device
 601  *
 602  * This is similar to blk_show_device() but returns an error if the block
 603  * device type is unknown.
 604  *
 605  * @if_type:    Block device type
 606  * @devnum:     Device number
 607  * @return 0 if OK, -ENODEV for invalid device number, -ENOENT if the block
 608  * device is not connected
 609  */
 610 int blk_print_device_num(enum if_type if_type, int devnum);
 611
 612 /**
 613  * blk_print_part_devnum() - print the partition information for a device
 614  *
 615  * @if_type:    Block device type
 616  * @devnum:     Device number
 617  * @return 0 if OK, -ENOENT if the block device is not connected, -ENOSYS if
 618  * the interface type is not supported, other -ve on other error
 619  */
 620 int blk_print_part_devnum(enum if_type if_type, int devnum);
 621
 622 /**
 623  * blk_read_devnum() - read blocks from a device
 624  *
 625  * @if_type:    Block device type
 626  * @devnum:     Device number
 627  * @blkcnt:     Number of blocks to read
 628  * @buffer:     Address to write data to
 629  * @return number of blocks read, or -ve error number on error
 630  */
 631 ulong blk_read_devnum(enum if_type if_type, int devnum, lbaint_t start,
 632                       lbaint_t blkcnt, void *buffer);
 633
 634 /**
 635  * blk_write_devnum() - write blocks to a device
 636  *
 637  * @if_type:    Block device type
 638  * @devnum:     Device number
 639  * @blkcnt:     Number of blocks to write
 640  * @buffer:     Address to read data from
 641  * @return number of blocks written, or -ve error number on error
 642  */
 643 ulong blk_write_devnum(enum if_type if_type, int devnum, lbaint_t start,
 644                        lbaint_t blkcnt, const void *buffer);
 645
 646 /**
 647  * blk_select_hwpart_devnum() - select a hardware partition
 648  *
 649  * This is similar to blk_dselect_hwpart() but it looks up the interface and
 650  * device number.
 651  *
 652  * @if_type:    Block device type
 653  * @devnum:     Device number
 654  * @hwpart:     Partition number to select
 655  * @return 0 if OK, -ve on error
 656  */
 657 int blk_select_hwpart_devnum(enum if_type if_type, int devnum, int hwpart);
 658
 659 /**
 660  * blk_get_if_type_name() - Get the name of an interface type
 661  *
 662  * @if_type: Interface type to check
 663  * @return name of interface, or NULL if none
 664  */
 665 const char *blk_get_if_type_name(enum if_type if_type);
 666
 667 /**
 668  * blk_common_cmd() - handle common commands with block devices
 669  *
 670  * @args: Number of arguments to the command (argv[0] is the command itself)
 671  * @argv: Command arguments
 672  * @if_type: Interface type
 673  * @cur_devnump: Current device number for this interface type
 674  * @return 0 if OK, CMD_RET_ERROR on error
 675  */
 676 int blk_common_cmd(int argc, char * const argv[], enum if_type if_type,
 677                    int *cur_devnump);
 678
 679 #endif