M7350/bootable/bootloader/lk/lib/bio/mem.c
2024-09-09 08:52:07 +00:00

102 lines
2.9 KiB
C

/*
* 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.
*/
#include <debug.h>
#include <string.h>
#include <stdlib.h>
#include <lib/bio.h>
#define LOCAL_TRACE 0
#define BLOCKSIZE 512
typedef struct mem_bdev {
bdev_t dev; // base device
void *ptr;
} mem_bdev_t;
static ssize_t mem_bdev_read(bdev_t *bdev, void *buf, off_t offset, size_t len)
{
mem_bdev_t *mem = (mem_bdev_t *)bdev;
LTRACEF("bdev %s, buf %p, offset %lld, len %zu\n", bdev->name, buf, offset, len);
memcpy(buf, (uint8_t *)mem->ptr + offset, len);
return len;
}
static ssize_t mem_bdev_read_block(struct bdev *bdev, void *buf, bnum_t block, uint count)
{
mem_bdev_t *mem = (mem_bdev_t *)bdev;
LTRACEF("bdev %s, buf %p, block %u, count %u\n", bdev->name, buf, block, count);
memcpy(buf, (uint8_t *)mem->ptr + block * BLOCKSIZE, count * BLOCKSIZE);
return count * BLOCKSIZE;
}
static ssize_t mem_bdev_write(bdev_t *bdev, const void *buf, off_t offset, size_t len)
{
mem_bdev_t *mem = (mem_bdev_t *)bdev;
LTRACEF("bdev %s, buf %p, offset %lld, len %zu\n", bdev->name, buf, offset, len);
memcpy((uint8_t *)mem->ptr + offset, buf, len);
return len;
}
static ssize_t mem_bdev_write_block(struct bdev *bdev, const void *buf, bnum_t block, uint count)
{
mem_bdev_t *mem = (mem_bdev_t *)bdev;
LTRACEF("bdev %s, buf %p, block %u, count %u\n", bdev->name, buf, block, count);
memcpy((uint8_t *)mem->ptr + block * BLOCKSIZE, buf, count * BLOCKSIZE);
return count * BLOCKSIZE;
}
int create_membdev(const char *name, void *ptr, size_t len)
{
mem_bdev_t *mem = malloc(sizeof(mem_bdev_t));
/* set up the base device */
bio_initialize_bdev(&mem->dev, name, BLOCKSIZE, len / BLOCKSIZE);
/* our bits */
mem->ptr = ptr;
mem->dev.read = mem_bdev_read;
mem->dev.read_block = mem_bdev_read_block;
mem->dev.write = mem_bdev_write;
mem->dev.write_block = mem_bdev_write_block;
/* register it */
bio_register_device(&mem->dev);
return 0;
}