src/bsp/lk/lib/bio/include/lib/bio.h

/*
 * Copyright (c) 2009 Travis Geiselbrecht
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#pragma once

#include <assert.h>
#include <sys/types.h>
#include <list.h>

__BEGIN_CDECLS;

#define BIO_FLAGS_NONE                (0 << 0)
#define BIO_FLAG_CACHE_ALIGNED_READS  (1 << 0)
#define BIO_FLAG_CACHE_ALIGNED_WRITES (1 << 1)

typedef uint32_t bnum_t;

typedef struct bio_erase_geometry_info {
    off_t  start;  // start of the region in bytes.
    off_t  size;
    size_t erase_size;
    size_t erase_shift;
} bio_erase_geometry_info_t;

typedef struct bdev {
    struct list_node node;
    volatile int ref;

    /* info about the block device */
    char *name;
    off_t total_size;

    size_t block_size;
    size_t block_shift;
    bnum_t block_count;
    char *unique_uuid;
    char *label;
    bool is_gpt;

    size_t geometry_count;
    const bio_erase_geometry_info_t* geometry;

    uint8_t erase_byte;

    uint32_t flags;

    /* function pointers */
    ssize_t (*read)(struct bdev *, void *buf, off_t offset, size_t len);
    ssize_t (*read_block)(struct bdev *, void *buf, bnum_t block, uint count);
    ssize_t (*write)(struct bdev *, const void *buf, off_t offset, size_t len);
    ssize_t (*write_block)(struct bdev *, const void *buf, bnum_t block, uint count);
    ssize_t (*erase)(struct bdev *, off_t offset, size_t len);
    int (*ioctl)(struct bdev *, int request, void *argp);
    void (*close)(struct bdev *);
} bdev_t;

/* user api */
bdev_t *bio_open(const char *name);
bdev_t *bio_open_by_label(const char *label);
void bio_close(bdev_t *dev);
ssize_t bio_read(bdev_t *dev, void *buf, off_t offset, size_t len);
ssize_t bio_read_block(bdev_t *dev, void *buf, bnum_t block, uint count);
ssize_t bio_write(bdev_t *dev, const void *buf, off_t offset, size_t len);
ssize_t bio_write_block(bdev_t *dev, const void *buf, bnum_t block, uint count);
ssize_t bio_erase(bdev_t *dev, off_t offset, size_t len);
int bio_ioctl(bdev_t *dev, int request, void *argp);

/* register a block device */
void bio_register_device(bdev_t *dev);
void bio_unregister_device(bdev_t *dev);

/* used during bdev construction */
void bio_initialize_bdev(bdev_t* dev,
                         const char* name,
                         size_t block_size,
                         bnum_t block_count,
                         size_t geometry_count,
                         const bio_erase_geometry_info_t* geometry,
                         const uint32_t flags);

/* debug stuff */
void bio_dump_devices(void);

/* subdevice support */
status_t bio_publish_subdevice(const char *parent_dev,
                               const char *subdev,
                               bnum_t startblock,
                               bnum_t block_count);

/* memory based block device */
int create_membdev(const char *name, void *ptr, size_t len);
void *destroy_membdev(const char *name);

/* helper routine to trim an offset + len to the device */
size_t bio_trim_range(const bdev_t *dev, off_t offset, size_t len);

/* helper routine to trim to a block range in the device */
uint bio_trim_block_range(const bdev_t *dev, bnum_t block, uint count);

/* utility routine */
static inline bool bio_does_overlap(uint64_t start1, uint64_t len1,
                                    uint64_t start2, uint64_t len2)
{
    uint64_t end1 = start1 + len1;
    uint64_t end2 = start2 + len2;

    DEBUG_ASSERT(end1 >= start1);
    DEBUG_ASSERT(end2 >= start2);

    return (((start1 >= start2) && (start1 < end2)) ||
            ((start2 >= start1) && (start2 < end1)));
}

static inline bool bio_contains_range(uint64_t container_start, uint64_t container_len,
                                      uint64_t contained_start, uint64_t contained_len)
{
    uint64_t container_end = container_start + container_len;
    uint64_t contained_end = contained_start + contained_len;

    DEBUG_ASSERT(container_end >= container_start);
    DEBUG_ASSERT(contained_end >= contained_start);

    return ((container_start <= contained_start) &&
            (container_end   >= contained_end));
}

/* generic bio ioctls */
enum bio_ioctl_num {
    BIO_IOCTL_NULL = 0,
    BIO_IOCTL_GET_MEM_MAP,  /* if supported, request a pointer to the memory map of the device */
    BIO_IOCTL_PUT_MEM_MAP,  /* if needed, return the pointer (to 'close' the map) */
    BIO_IOCTL_GET_MAP_ADDR, /* if supported, request a pointer to the memory map without putting the device into linear mode */
    BIO_IOCTL_CUSTOM_START = 0x100, /* for custom to add new enum */
};

__END_CDECLS;