int bchlib_teardown(FAR void *handle)
{
FAR struct bchlib_s *bch = (FAR struct bchlib_s *)handle;
DEBUGASSERT(handle);
/* Check that there are not outstanding reference counts on the object */
if (bch->refs > 0)
{
return -EBUSY;
}
/* Flush any pending data to the block driver */
bchlib_flushsector(bch);
/* Close the block driver */
(void)close_blockdriver(bch->inode);
/* Free the BCH state structure */
if (bch->buffer)
{
kfree(bch->buffer);
}
sem_destroy(&bch->sem);
kfree(bch);
return OK;
}
static int bch_close(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct bchlib_s *bch;
int ret = OK;
DEBUGASSERT(inode && inode->i_private);
bch = (FAR struct bchlib_s *)inode->i_private;
/* Flush any dirty pages remaining in the cache */
bchlib_semtake(bch);
(void)bchlib_flushsector(bch);
/* Decrement the reference count (I don't use bchlib_decref() because I
* want the entire close operation to be atomic wrt other driver operations.
*/
if (bch->refs == 0)
{
ret = -EIO;
}
else
{
bch->refs--;
}
bchlib_semgive(bch);
return ret;
}
int bchlib_readsector(FAR struct bchlib_s *bch, size_t sector)
{
FAR struct inode *inode;
ssize_t ret = OK;
if (bch->sector != sector)
{
inode = bch->inode;
(void)bchlib_flushsector(bch);
bch->sector = (size_t)-1;
ret = inode->u.i_bops->read(inode, bch->buffer, sector, 1);
if (ret < 0)
{
fdbg("Read failed: %d\n");
}
bch->sector = sector;
#if defined(CONFIG_BCH_ENCRYPTION)
bch_cypher(bch, CYPHER_DECRYPT);
#endif
}
return (int)ret;
}
ssize_t bchlib_write(FAR void *handle, FAR const char *buffer, size_t offset, size_t len)
{
FAR struct bchlib_s *bch = (FAR struct bchlib_s *)handle;
size_t nsectors;
size_t sector;
uint16_t sectoffset;
size_t nbytes;
size_t byteswritten;
int ret;
/* Get rid of this special case right away */
if (len < 1)
{
return 0;
}
/* Convert the file position into a sector number and offset. */
sector = offset / bch->sectsize;
sectoffset = offset - sector * bch->sectsize;
if (sector >= bch->nsectors)
{
return -EFBIG;
}
/* Write the initial partial sector */
byteswritten = 0;
if (sectoffset > 0)
{
/* Read the full sector into the sector buffer */
bchlib_readsector(bch, sector);
/* Copy the tail end of the sector from the user buffer */
if (sectoffset + len > bch->sectsize)
{
nbytes = bch->sectsize - sectoffset;
}
else
{
nbytes = len;
}
memcpy(&bch->buffer[sectoffset], buffer, nbytes);
bch->dirty = true;
/* Adjust pointers and counts */
sector++;
if (sector >= bch->nsectors)
{
return nbytes;
}
byteswritten = nbytes;
buffer += nbytes;
len -= nbytes;
}
/* Then write all of the full sectors following the partial sector
* directly from the user buffer.
*/
if (len >= bch->sectsize )
{
nsectors = len / bch->sectsize;
if (sector + nsectors > bch->nsectors)
{
nsectors = bch->nsectors - sector;
}
/* Write the contiguous sectors */
ret = bch->inode->u.i_bops->write(bch->inode, (FAR uint8_t *)buffer,
sector, nsectors);
if (ret < 0)
{
fdbg("Write failed: %d\n", ret);
return ret;
}
/* Adjust pointers and counts */
sector += nsectors;
nbytes = nsectors * bch->sectsize;
byteswritten += nbytes;
if (sector >= bch->nsectors)
{
return byteswritten;
}
buffer += nbytes;
len -= nbytes;
}
/* Then write any partial final sector */
if (len > 0)
{
/* Read the sector into the sector buffer */
bchlib_readsector(bch, sector);
/* Copy the head end of the sector from the user buffer */
memcpy(bch->buffer, buffer, len);
bch->dirty = true;
/* Adjust counts */
byteswritten += len;
}
/* Finally, flush any cached writes to the device as well */
ret = bchlib_flushsector(bch);
if (ret < 0)
{
fdbg("Flush failed: %d\n", ret);
return ret;
}
return byteswritten;
}
