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#include <stdint.h>
#include <mlibc/stdlib.h>
#include <kernel/fs/ata_pio.h>
#include <kernel/fs/marfs/marfs.h>
uint8_t marfs_init(struct ATA_INTERFACE *_iface) {
iface = _iface;
uint16_t identifydata[256 * 2];
uint8_t ret = ATA_identify(iface, identifydata);
maxLBA = (identifydata[61] << 16) + identifydata[60];
return ret;
}
uint32_t marfs_get_max_lba(void) { return maxLBA; }
uint8_t marfs_write_mbr(uint8_t *mbr) {
return ATA_write28(iface, 0, mbr);
}
struct marfs_SUPERBLOCK *marfs_read_superblock() {
struct marfs_SUPERBLOCK *p = (struct marfs_SUPERBLOCK *) ATA_read28(iface, 1);
sb_cache = *p;
return p;
}
uint8_t marfs_writeSB(struct marfs_SUPERBLOCK *sb) {
sb_cache = *sb;
return ATA_write28(iface, 1, (uint8_t *) sb);
}
uint32_t marfs_get_free_lba_block(void) {
uint32_t offset = 2 + sb_cache.s_first_chunk;
uint8_t *p = 0;
for (uint32_t i = 0; i < sb_cache.n_chunks; i++) {
p = ATA_read28(iface, offset);
if (!(*p & 0x80)) break;
kfree(p);
offset += 512;
}
offset++;
for (uint16_t i = 1; i < 512; i++) {
if (!p[i]) break;
offset++;
}
kfree(p);
ATA_clear28(iface, offset);
return offset;
}
static uint8_t marfs_mark_block(uint32_t lba_sector, uint8_t mode) {
lba_sector -= 2;
lba_sector -= sb_cache.s_first_chunk;
uint16_t block_in_chunk = lba_sector % 512;
lba_sector /= 512;
lba_sector = 2 + sb_cache.s_first_chunk + (512 * lba_sector);
uint8_t *p = ATA_read28(iface, lba_sector);
p[block_in_chunk] = mode;
if (mode == 0) {
p[0] = 0;
} else {
uint8_t full_chunk = 1;
for (uint16_t i = 1; i < 512; i++) {
if (!p[i]) {
full_chunk = 0;
break;
}
}
p[0] = full_chunk;
}
uint8_t ret = ATA_write28(iface, lba_sector, p);
kfree(p);
return ret;
}
uint8_t marfs_mark_block_as_free(uint32_t lba_sector) { return marfs_mark_block(lba_sector, 0); }
uint8_t marfs_mark_block_as_used(uint32_t lba_sector) { return marfs_mark_block(lba_sector, 1); }
uint32_t marfs_get_free_lba_inode(void) {
uint32_t offset;
for (offset = 2; offset < 2 + sb_cache.n_inodes; offset++) {
struct marfs_INODE *inode = (struct marfs_INODE *) ATA_read28(iface, offset);
uint8_t used = inode->isUsed;
kfree(inode);
if (!used) break;
}
return offset;
}
void marfs_mark_inode_as_free(uint32_t lba_sector) {
struct marfs_INODE *inode = (struct marfs_INODE *) ATA_read28(iface, lba_sector);
inode->isUsed = 0;
ATA_write28(iface, lba_sector, (uint8_t *) inode);
kfree(inode);
}
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