ref: 809b27e9dcf7f7120b98b03b13ceb624302e8183
dir: /lwext4/ext4_blockdev.c/
/*
* Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup lwext4
* @{
*/
/**
* @file ext4_blockdev.c
* @brief Block device module.
*/
#include "ext4_config.h"
#include "ext4_blockdev.h"
#include "ext4_errno.h"
#include "ext4_debug.h"
#include <string.h>
#include <stdlib.h>
static void ext4_bdif_lock(struct ext4_blockdev *bdev)
{
if (!bdev->bdif->lock)
return;
int r = bdev->bdif->lock(bdev);
ext4_assert(r == EOK);
}
static void ext4_bdif_unlock(struct ext4_blockdev *bdev)
{
if (!bdev->bdif->unlock)
return;
int r = bdev->bdif->unlock(bdev);
ext4_assert(r == EOK);
}
static int ext4_bdif_bread(struct ext4_blockdev *bdev, void *buf,
uint64_t blk_id, uint32_t blk_cnt)
{
ext4_bdif_lock(bdev);
int r = bdev->bdif->bread(bdev, buf, blk_id, blk_cnt);
bdev->bdif->bread_ctr++;
ext4_bdif_unlock(bdev);
return r;
}
static int ext4_bdif_bwrite(struct ext4_blockdev *bdev, const void *buf,
uint64_t blk_id, uint32_t blk_cnt)
{
ext4_bdif_lock(bdev);
int r = bdev->bdif->bwrite(bdev, buf, blk_id, blk_cnt);
bdev->bdif->bwrite_ctr++;
ext4_bdif_unlock(bdev);
return r;
}
int ext4_block_init(struct ext4_blockdev *bdev)
{
int rc;
ext4_assert(bdev);
ext4_assert(bdev->bdif);
ext4_assert(bdev->bdif->open &&
bdev->bdif->close &&
bdev->bdif->bread &&
bdev->bdif->bwrite);
if (bdev->bdif->ph_refctr) {
bdev->bdif->ph_refctr++;
return EOK;
}
/*Low level block init*/
rc = bdev->bdif->open(bdev);
if (rc != EOK)
return rc;
bdev->bdif->ph_refctr = 1;
return EOK;
}
int ext4_block_bind_bcache(struct ext4_blockdev *bdev, struct ext4_bcache *bc)
{
ext4_assert(bdev && bc);
bdev->bc = bc;
bc->bdev = bdev;
return EOK;
}
void ext4_block_set_lb_size(struct ext4_blockdev *bdev, uint64_t lb_bsize)
{
/*Logical block size has to be multiply of physical */
ext4_assert(!(lb_bsize % bdev->bdif->ph_bsize));
bdev->lg_bsize = lb_bsize;
bdev->lg_bcnt = bdev->part_size / lb_bsize;
}
int ext4_block_fini(struct ext4_blockdev *bdev)
{
ext4_assert(bdev);
if (!bdev->bdif->ph_refctr)
return EOK;
bdev->bdif->ph_refctr--;
if (bdev->bdif->ph_refctr)
return EOK;
/*Low level block fini*/
return bdev->bdif->close(bdev);
}
int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf)
{
int r;
struct ext4_bcache *bc = bdev->bc;
if (ext4_bcache_test_flag(buf, BC_DIRTY) &&
ext4_bcache_test_flag(buf, BC_UPTODATE)) {
r = ext4_blocks_set_direct(bdev, buf->data, buf->lba, 1);
if (r) {
if (buf->end_write) {
bc->dont_shake = true;
buf->end_write(bc, buf, r, buf->end_write_arg);
bc->dont_shake = false;
}
return r;
}
ext4_bcache_remove_dirty_node(bc, buf);
ext4_bcache_clear_flag(buf, BC_DIRTY);
if (buf->end_write) {
bc->dont_shake = true;
buf->end_write(bc, buf, r, buf->end_write_arg);
bc->dont_shake = false;
}
}
return EOK;
}
int ext4_block_flush_lba(struct ext4_blockdev *bdev, uint64_t lba)
{
int r = EOK;
struct ext4_buf *buf;
struct ext4_block b;
buf = ext4_bcache_find_get(bdev->bc, &b, lba);
if (buf) {
r = ext4_block_flush_buf(bdev, buf);
ext4_bcache_free(bdev->bc, &b);
}
return r;
}
int ext4_block_cache_shake(struct ext4_blockdev *bdev)
{
int r = EOK;
struct ext4_buf *buf;
if (bdev->bc->dont_shake)
return EOK;
while (!RB_EMPTY(&bdev->bc->lru_root) &&
ext4_bcache_is_full(bdev->bc)) {
buf = ext4_buf_lowest_lru(bdev->bc);
ext4_assert(buf);
if (ext4_bcache_test_flag(buf, BC_DIRTY)) {
r = ext4_block_flush_buf(bdev, buf);
if (r != EOK)
break;
}
ext4_bcache_drop_buf(bdev->bc, buf);
}
return r;
}
int ext4_block_get_noread(struct ext4_blockdev *bdev, struct ext4_block *b,
uint64_t lba)
{
bool is_new;
int r;
ext4_assert(bdev && b);
if (!bdev->bdif->ph_refctr)
return EIO;
if (!(lba < bdev->lg_bcnt))
return ERANGE;
b->lb_id = lba;
/*If cache is full we have to (flush and) drop it anyway :(*/
r = ext4_block_cache_shake(bdev);
if (r != EOK)
return r;
r = ext4_bcache_alloc(bdev->bc, b, &is_new);
if (r != EOK)
return r;
if (!b->data)
return ENOMEM;
return EOK;
}
int ext4_block_get(struct ext4_blockdev *bdev, struct ext4_block *b,
uint64_t lba)
{
int r = ext4_block_get_noread(bdev, b, lba);
if (r != EOK)
return r;
if (ext4_bcache_test_flag(b->buf, BC_UPTODATE)) {
/* Data in the cache is up-to-date.
* Reading from physical device is not required */
return EOK;
}
r = ext4_blocks_get_direct(bdev, b->data, lba, 1);
if (r != EOK) {
ext4_bcache_free(bdev->bc, b);
b->lb_id = 0;
return r;
}
/* Mark buffer up-to-date, since
* fresh data is read from physical device just now. */
ext4_bcache_set_flag(b->buf, BC_UPTODATE);
return EOK;
}
int ext4_block_set(struct ext4_blockdev *bdev, struct ext4_block *b)
{
ext4_assert(bdev && b);
ext4_assert(b->buf);
if (!bdev->bdif->ph_refctr)
return EIO;
return ext4_bcache_free(bdev->bc, b);
}
int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
uint32_t cnt)
{
uint64_t pba;
uint32_t pb_cnt;
ext4_assert(bdev && buf);
pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
return ext4_bdif_bread(bdev, buf, pba, pb_cnt * cnt);
}
int ext4_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
uint64_t lba, uint32_t cnt)
{
uint64_t pba;
uint32_t pb_cnt;
ext4_assert(bdev && buf);
pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
return ext4_bdif_bwrite(bdev, buf, pba, pb_cnt * cnt);
}
int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
const void *buf, uint32_t len)
{
uint64_t block_idx;
uint32_t blen;
uint32_t unalg;
int r = EOK;
const uint8_t *p = (void *)buf;
ext4_assert(bdev && buf);
if (!bdev->bdif->ph_refctr)
return EIO;
if (off + len > bdev->part_size)
return EINVAL; /*Ups. Out of range operation*/
block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
/*OK lets deal with the first possible unaligned block*/
unalg = (off & (bdev->bdif->ph_bsize - 1));
if (unalg) {
uint32_t wlen = (bdev->bdif->ph_bsize - unalg) > len
? len
: (bdev->bdif->ph_bsize - unalg);
r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
if (r != EOK)
return r;
memcpy(bdev->bdif->ph_bbuf + unalg, p, wlen);
r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
if (r != EOK)
return r;
p += wlen;
len -= wlen;
block_idx++;
}
/*Aligned data*/
blen = len / bdev->bdif->ph_bsize;
r = ext4_bdif_bwrite(bdev, p, block_idx, blen);
if (r != EOK)
return r;
p += bdev->bdif->ph_bsize * blen;
len -= bdev->bdif->ph_bsize * blen;
block_idx += blen;
/*Rest of the data*/
if (len) {
r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
if (r != EOK)
return r;
memcpy(bdev->bdif->ph_bbuf, p, len);
r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
if (r != EOK)
return r;
}
return r;
}
int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
uint32_t len)
{
uint64_t block_idx;
uint32_t blen;
uint32_t unalg;
int r = EOK;
uint8_t *p = (void *)buf;
ext4_assert(bdev && buf);
if (!bdev->bdif->ph_refctr)
return EIO;
if (off + len > bdev->part_size)
return EINVAL; /*Ups. Out of range operation*/
block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
/*OK lets deal with the first possible unaligned block*/
unalg = (off & (bdev->bdif->ph_bsize - 1));
if (unalg) {
uint32_t rlen = (bdev->bdif->ph_bsize - unalg) > len
? len
: (bdev->bdif->ph_bsize - unalg);
r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
if (r != EOK)
return r;
memcpy(p, bdev->bdif->ph_bbuf + unalg, rlen);
p += rlen;
len -= rlen;
block_idx++;
}
/*Aligned data*/
blen = len / bdev->bdif->ph_bsize;
r = ext4_bdif_bread(bdev, p, block_idx, blen);
if (r != EOK)
return r;
p += bdev->bdif->ph_bsize * blen;
len -= bdev->bdif->ph_bsize * blen;
block_idx += blen;
/*Rest of the data*/
if (len) {
r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
if (r != EOK)
return r;
memcpy(p, bdev->bdif->ph_bbuf, len);
}
return r;
}
int ext4_block_cache_flush(struct ext4_blockdev *bdev)
{
while (!SLIST_EMPTY(&bdev->bc->dirty_list)) {
int r;
struct ext4_buf *buf = SLIST_FIRST(&bdev->bc->dirty_list);
ext4_assert(buf);
r = ext4_block_flush_buf(bdev, buf);
if (r != EOK)
return r;
}
return EOK;
}
int ext4_block_cache_write_back(struct ext4_blockdev *bdev, uint8_t on_off)
{
if (on_off)
bdev->cache_write_back++;
if (!on_off && bdev->cache_write_back)
bdev->cache_write_back--;
if (bdev->cache_write_back)
return EOK;
/*Flush data in all delayed cache blocks*/
return ext4_block_cache_flush(bdev);
}
/**
* @}
*/