DragonOS/kernel/filesystem/fat32/fat32.c

#include "fat32.h"
#include <common/kprint.h>
#include <driver/disk/ahci/ahci.h>
#include <filesystem/MBR.h>
#include <process/spinlock.h>
#include <mm/slab.h>

struct vfs_super_block_operations_t fat32_sb_ops;
struct vfs_dir_entry_operations_t fat32_dEntry_ops;
struct vfs_file_operations_t fat32_file_ops;
struct vfs_inode_operations_t fat32_inode_ops;

/**
 * @brief 注册指定磁盘上的指定分区的fat32文件系统
 *
 * @param ahci_ctrl_num ahci控制器编号
 * @param ahci_port_num ahci控制器端口编号
 * @param part_num 磁盘分区编号
 *
 * @return struct vfs_super_block_t * 文件系统的超级块
 */
struct vfs_superblock_t *fat32_register_partition(uint8_t ahci_ctrl_num, uint8_t ahci_port_num, uint8_t part_num)
{

    struct MBR_disk_partition_table_t *DPT = MBR_read_partition_table(ahci_ctrl_num, ahci_port_num);

    //	for(i = 0 ;i < 512 ; i++)
    //		color_printk(PURPLE,WHITE,"%02x",buf[i]);
    printk_color(ORANGE, BLACK, "DPTE[0] start_LBA:%#018lx\ttype:%#018lx\n", DPT->DPTE[part_num].starting_LBA, DPT->DPTE[part_num].type);
    uint8_t buf[512] = {0};

    // 读取文件系统的boot扇区
    ahci_operation.transfer(ATA_CMD_READ_DMA_EXT, DPT->DPTE[part_num].starting_LBA, 1, (uint64_t)&buf, ahci_ctrl_num, ahci_port_num);

    // 挂载文件系统到vfs
    return vfs_mount_fs("FAT32", (void *)(&DPT->DPTE[part_num]), VFS_DPT_MBR, buf, ahci_ctrl_num, ahci_port_num, part_num);
}

/**
 * @brief 读取指定簇的FAT表项
 *
 * @param fsbi fat32超级块私有信息结构体
 * @param cluster 指定簇
 * @return uint32_t 下一个簇的簇号
 */
uint32_t fat32_read_FAT_entry(fat32_sb_info_t *fsbi, uint32_t cluster)
{
    // 计算每个扇区内含有的FAT表项数
    // FAT每项4bytes
    uint32_t fat_ent_per_sec = (fsbi->bootsector.BPB_BytesPerSec >> 2); // 该值应为2的n次幂
    uint32_t buf[256];
    memset(buf, 0, fsbi->bootsector.BPB_BytesPerSec);

    // 读取一个sector的数据，
    ahci_operation.transfer(ATA_CMD_READ_DMA_EXT, fsbi->FAT1_base_sector + (cluster / fat_ent_per_sec), 1,
                            (uint64_t)&buf, fsbi->ahci_ctrl_num, fsbi->ahci_port_num);

    // 返回下一个fat表项的值（也就是下一个cluster）
    return buf[cluster & (fat_ent_per_sec - 1)] & 0x0fffffff;
    ;
}

/**
 * @brief 写入指定簇的FAT表项
 *
 * @param fsbi fat32超级块私有信息结构体
 * @param cluster 指定簇
 * @param value 要写入该fat表项的值
 * @return uint32_t errcode
 */
uint32_t fat32_write_FAT_entry(fat32_sb_info_t *fsbi, uint32_t cluster, uint32_t value)
{
    // 计算每个扇区内含有的FAT表项数
    // FAT每项4bytes
    uint32_t fat_ent_per_sec = (fsbi->bootsector.BPB_BytesPerSec >> 2); // 该值应为2的n次幂
    uint32_t buf[256];
    memset(buf, 0, fsbi->bootsector.BPB_BytesPerSec);

    ahci_operation.transfer(ATA_CMD_READ_DMA_EXT, fsbi->FAT1_base_sector + (cluster / fat_ent_per_sec), 1,
                            (uint64_t)&buf, fsbi->ahci_ctrl_num, fsbi->ahci_port_num);

    buf[cluster & (fat_ent_per_sec - 1)] = (buf[cluster & (fat_ent_per_sec - 1)] & 0xf0000000) | (value & 0x0fffffff);
    // 向FAT1和FAT2写入数据
    ahci_operation.transfer(ATA_CMD_WRITE_DMA_EXT, fsbi->FAT1_base_sector + (cluster / fat_ent_per_sec), 1,
                            (uint64_t)&buf, fsbi->ahci_ctrl_num, fsbi->ahci_port_num);
    ahci_operation.transfer(ATA_CMD_WRITE_DMA_EXT, fsbi->FAT2_base_sector + (cluster / fat_ent_per_sec), 1,
                            (uint64_t)&buf, fsbi->ahci_ctrl_num, fsbi->ahci_port_num);

    return 0;
}

/**
 * @brief 在父目录中寻找指定的目录项
 *
 * @param parent_inode 父目录项的inode
 * @param dest_inode 搜索目标目录项的inode
 * @return struct vfs_dir_entry_t* 目标目录项
 */
struct vfs_dir_entry_t *fat32_lookup(struct vfs_index_node_t *parent_inode, struct vfs_dir_entry_t *dest_dentry)
{
    int errcode = 0;

    struct fat32_inode_info_t *finode = (struct fat32_inode_info_t *)parent_inode->private_inode_info;
    fat32_sb_info_t *fsbi = (fat32_sb_info_t *)parent_inode->sb->private_sb_info;

    uint8_t *buf = kmalloc(fsbi->bytes_per_clus, 0);
    memset(buf, 0, fsbi->bytes_per_clus);

    // 计算父目录项的起始簇号
    uint32_t cluster = finode->first_clus;

    struct fat32_Directory_t *tmp_dEntry = NULL;

    while (true)
    {

        // 计算父目录项的起始LBA扇区号
        uint64_t sector = fsbi->first_data_sector + (cluster - 2) * fsbi->sec_per_clus;
        // kdebug("fat32_part_info[part_id].bootsector.BPB_SecPerClus=%d",fat32_part_info[part_id].bootsector.BPB_SecPerClus);
        // kdebug("sector=%d",sector);

        // 读取父目录项的起始簇数据
        ahci_operation.transfer(ATA_CMD_READ_DMA_EXT, sector, fsbi->sec_per_clus, (uint64_t)buf, fsbi->ahci_ctrl_num, fsbi->ahci_port_num);
        // ahci_operation.transfer(ATA_CMD_READ_DMA_EXT, sector, fat32_part_info[part_id].bootsector.BPB_SecPerClus, (uint64_t)buf, fat32_part_info[part_id].ahci_ctrl_num, fat32_part_info[part_id].ahci_port_num);

        tmp_dEntry = (struct fat32_Directory_t *)buf;

        // 查找短目录项
        for (int i = 0; i < fsbi->bytes_per_clus; i += 32, ++tmp_dEntry)
        {
            // 跳过长目录项
            if (tmp_dEntry->DIR_Attr == ATTR_LONG_NAME)
                continue;

            // 跳过无效页表项、空闲页表项
            if (tmp_dEntry->DIR_Name[0] == 0xe5 || tmp_dEntry->DIR_Name[0] == 0x00 || tmp_dEntry->DIR_Name[0] == 0x05)
                continue;

            // 找到长目录项，位于短目录项之前
            struct fat32_LongDirectory_t *tmp_ldEntry = (struct fat32_LongDirectory_t *)tmp_dEntry - 1;

            int js = 0;
            // 遍历每个长目录项
            while (tmp_ldEntry->LDIR_Attr == ATTR_LONG_NAME && tmp_ldEntry->LDIR_Ord != 0xe5)
            {
                // 比较name1
                for (int x = 0; x < 5; ++x)
                {
                    if (js > dest_dentry->name_length && tmp_ldEntry->LDIR_Name1[x] == 0xffff)
                        continue;
                    else if (js > dest_dentry->name_length || tmp_ldEntry->LDIR_Name1[x] != (uint16_t)(dest_dentry->name[js++])) // 文件名不匹配，检索下一个短目录项
                        goto continue_cmp_fail;
                }

                // 比较name2
                for (int x = 0; x < 6; ++x)
                {
                    if (js > dest_dentry->name_length && tmp_ldEntry->LDIR_Name2[x] == 0xffff)
                        continue;
                    else if (js > dest_dentry->name_length || tmp_ldEntry->LDIR_Name2[x] != (uint16_t)(dest_dentry->name[js++])) // 文件名不匹配，检索下一个短目录项
                        goto continue_cmp_fail;
                }

                // 比较name3
                for (int x = 0; x < 2; ++x)
                {
                    if (js > dest_dentry->name_length && tmp_ldEntry->LDIR_Name3[x] == 0xffff)
                        continue;
                    else if (js > dest_dentry->name_length || tmp_ldEntry->LDIR_Name3[x] != (uint16_t)(dest_dentry->name[js++])) // 文件名不匹配，检索下一个短目录项
                        goto continue_cmp_fail;
                }

                if (js >= dest_dentry->name_length) // 找到需要的目录项，返回
                {
                    goto find_lookup_success;
                }

                --tmp_ldEntry; // 检索下一个长目录项
            }

            // 不存在长目录项，匹配短目录项的基础名
            js = 0;
            for (int x = 0; x < 8; ++x)
            {
                switch (tmp_dEntry->DIR_Name[x])
                {
                case ' ':
                    if (!(tmp_dEntry->DIR_Attr & ATTR_DIRECTORY)) // 不是文件夹（是文件）
                    {
                        if (dest_dentry->name[js] == '.')
                            continue;
                        else if (tmp_dEntry->DIR_Name[x] == dest_dentry->name[js])
                        {
                            ++js;
                            break;
                        }
                        else
                            goto continue_cmp_fail;
                    }
                    else // 是文件夹
                    {
                        if (js < dest_dentry->name_length && tmp_dEntry->DIR_Name[x] == dest_dentry->name[js]) // 当前位正确匹配
                        {
                            ++js;
                            break; // 进行下一位的匹配
                        }
                        else if (js == dest_dentry->name_length)
                            continue;
                        else
                            goto continue_cmp_fail;
                    }
                    break;

                // 当前位是字母
                case 'A' ... 'Z':
                case 'a' ... 'z':
                    if (tmp_dEntry->DIR_NTRes & LOWERCASE_BASE) // 为兼容windows系统，检测DIR_NTRes字段
                    {
                        if (js < dest_dentry->name_length && (tmp_dEntry->DIR_Name[x] + 32 == dest_dentry->name[js]))
                        {
                            ++js;
                            break;
                        }
                        else
                            goto continue_cmp_fail;
                    }
                    else
                    {
                        if (js < dest_dentry->name_length && tmp_dEntry->DIR_Name[x] == dest_dentry->name[js])
                        {
                            ++js;
                            break;
                        }
                        else
                            goto continue_cmp_fail;
                    }
                    break;
                case '0' ... '9':
                    if (js < dest_dentry->name_length && tmp_dEntry->DIR_Name[x] == dest_dentry->name[js])
                    {
                        ++js;
                        break;
                    }
                    else
                        goto continue_cmp_fail;

                    break;
                default:
                    ++js;
                    break;
                }
            }

            // 若短目录项为文件，则匹配扩展名
            if (!(tmp_dEntry->DIR_Attr & ATTR_DIRECTORY))
            {
                ++js;
                for (int x = 8; x < 11; ++x)
                {
                    switch (tmp_dEntry->DIR_Name[x])
                    {
                        // 当前位是字母
                    case 'A' ... 'Z':
                    case 'a' ... 'z':
                        if (tmp_dEntry->DIR_NTRes & LOWERCASE_EXT) // 为兼容windows系统，检测DIR_NTRes字段
                        {
                            if ((tmp_dEntry->DIR_Name[x] + 32 == dest_dentry->name[js]))
                            {
                                ++js;
                                break;
                            }
                            else
                                goto continue_cmp_fail;
                        }
                        else
                        {
                            if (tmp_dEntry->DIR_Name[x] == dest_dentry->name[js])
                            {
                                ++js;
                                break;
                            }
                            else
                                goto continue_cmp_fail;
                        }
                        break;
                    case '0' ... '9':
                    case ' ':
                        if (tmp_dEntry->DIR_Name[x] == dest_dentry->name[js])
                        {
                            ++js;
                            break;
                        }
                        else
                            goto continue_cmp_fail;

                        break;

                    default:
                        goto continue_cmp_fail;
                        break;
                    }
                }
            }
            goto find_lookup_success;
        continue_cmp_fail:;
        }

        // 当前簇没有发现目标文件名，寻找下一个簇
        cluster = fat32_read_FAT_entry(fsbi, cluster);

        if (cluster >= 0x0ffffff7) // 寻找完父目录的所有簇，都没有找到目标文件名
        {
            kfree(buf);
            return NULL;
        }
    }
find_lookup_success:; // 找到目标dentry
    struct vfs_index_node_t *p = (struct vfs_index_node_t *)kmalloc(sizeof(struct vfs_index_node_t), 0);
    memset(p, 0, sizeof(struct vfs_index_node_t));

    p->file_size = tmp_dEntry->DIR_FileSize;
    // 计算文件占用的扇区数, 由于最小存储单位是簇，因此需要按照簇的大小来对齐扇区
    p->blocks = (p->file_size + fsbi->bytes_per_clus - 1) / fsbi->bytes_per_sec;
    p->attribute = (tmp_dEntry->DIR_Attr & ATTR_DIRECTORY) ? VFS_ATTR_DIR : VFS_ATTR_FILE;
    p->sb = parent_inode->sb;
    p->file_ops = &fat32_file_ops;
    p->inode_ops = &fat32_inode_ops;

    // 为inode的与文件系统相关的信息结构体分配空间
    p->private_inode_info = (void *)kmalloc(sizeof(fat32_inode_info_t), 0);
    memset(p->private_inode_info, 0, sizeof(fat32_inode_info_t));
    finode = (fat32_inode_info_t *)p->private_inode_info;

    finode->first_clus = ((tmp_dEntry->DIR_FstClusHI << 16) | tmp_dEntry->DIR_FstClusLO) & 0x0fffffff;
    finode->dEntry_location_clus = cluster;
    finode->dEntry_location_clus_offset = tmp_dEntry - (struct fat32_Directory_t *)buf; //计算dentry的偏移量
    finode->create_date = tmp_dEntry->DIR_CrtDate;
    finode->create_time = tmp_dEntry->DIR_CrtTime;
    finode->write_date = tmp_dEntry->DIR_WrtDate;
    finode->write_time = tmp_dEntry->DIR_WrtTime;

    dest_dentry->dir_inode = p;
    kfree(buf);
    return dest_dentry;
}

/**
 * @brief 按照路径查找文件
 *
 * @param part_id fat32分区id
 * @param path
 * @param flags 1：返回父目录项， 0：返回结果目录项
 * @return struct vfs_dir_entry_t* 目录项
 */
struct vfs_dir_entry_t *fat32_path_walk(char *path, uint64_t flags)
{

    struct vfs_dir_entry_t *parent = vfs_root_sb->root;
    // 去除路径前的斜杠
    while (*path == '/')
        ++path;

    if ((!*path) || (*path == '\0'))
        return parent;

    struct vfs_dir_entry_t *dentry;

    while (true)
    {
        // 提取出下一级待搜索的目录名或文件名，并保存在dEntry_name中
        char *tmp_path = path;
        while ((*path && *path != '\0') && (*path != '/'))
            ++path;
        int tmp_path_len = path - tmp_path;

        dentry = (struct vfs_dir_entry_t *)kmalloc(sizeof(struct vfs_dir_entry_t), 0);
        memset(dentry, 0, sizeof(struct vfs_dir_entry_t));
        // 为目录项的名称分配内存
        dentry->name = (char *)kmalloc(tmp_path_len + 1, 0);
        // 貌似这里不需要memset，因为空间会被覆盖
        // memset(dentry->name, 0, tmp_path_len+1);

        memcpy(dentry->name, tmp_path, tmp_path_len);
        dentry->name[tmp_path_len] = '\0';
        dentry->name_length = tmp_path_len;

        if (parent->dir_inode->inode_ops->lookup(parent->dir_inode, dentry) == NULL)
        {
            // 搜索失败
            kerror("cannot find the file/dir : %s", dentry->name);
            kfree(dentry->name);
            kfree(dentry);
            return NULL;
        }
        // 找到子目录项
        // 初始化子目录项的entry
        list_init(&dentry->child_node_list);
        list_init(&dentry->subdirs_list);
        dentry->parent = parent;

        while (*path == '/')
            ++path;

        if ((!*path) || (*path == '\0')) //  已经到达末尾
        {
            if (flags & 1) // 返回父目录
            {
                return parent;
            }

            return dentry;
        }

        parent = dentry;
    }
}

/**
 * @brief 创建fat32文件系统的超级块
 *
 * @param DPTE 磁盘分区表entry
 * @param DPT_type 磁盘分区表类型
 * @param buf fat32文件系统的引导扇区
 * @return struct vfs_superblock_t* 创建好的超级块
 */
struct vfs_superblock_t *fat32_read_superblock(void *DPTE, uint8_t DPT_type, void *buf, int8_t ahci_ctrl_num, int8_t ahci_port_num, int8_t part_num)
{
    if (DPT_type != VFS_DPT_MBR) // 暂时只支持MBR分区表
    {
        kerror("fat32_read_superblock(): Unsupported DPT!");
        return NULL;
    }

    // 分配超级块的空间
    struct vfs_superblock_t *sb_ptr = (struct vfs_superblock_t *)kmalloc(sizeof(struct vfs_superblock_t), 0);
    memset(sb_ptr, 0, sizeof(struct vfs_superblock_t));

    sb_ptr->sb_ops = &fat32_sb_ops;
    sb_ptr->private_sb_info = kmalloc(sizeof(fat32_sb_info_t), 0);
    memset(sb_ptr->private_sb_info, 0, sizeof(fat32_sb_info_t));

    struct fat32_BootSector_t *fbs = (struct fat32_BootSector_t *)buf;

    fat32_sb_info_t *fsbi = (fat32_sb_info_t *)(sb_ptr->private_sb_info);

    // MBR分区表entry
    struct MBR_disk_partition_table_entry_t *MBR_DPTE = (struct MBR_disk_partition_table_entry_t *)DPTE;
    fsbi->ahci_ctrl_num = ahci_ctrl_num;
    fsbi->ahci_port_num = ahci_port_num;
    fsbi->part_num = part_num;

    fsbi->starting_sector = MBR_DPTE->starting_LBA;
    fsbi->sector_count = MBR_DPTE->total_sectors;
    fsbi->sec_per_clus = fbs->BPB_SecPerClus;
    fsbi->bytes_per_clus = fbs->BPB_SecPerClus * fbs->BPB_BytesPerSec;
    fsbi->bytes_per_sec = fbs->BPB_BytesPerSec;
    fsbi->first_data_sector = MBR_DPTE->starting_LBA + fbs->BPB_RsvdSecCnt + fbs->BPB_FATSz32 * fbs->BPB_NumFATs;
    fsbi->FAT1_base_sector = MBR_DPTE->starting_LBA + fbs->BPB_RsvdSecCnt;
    fsbi->FAT2_base_sector = fsbi->FAT1_base_sector + fbs->BPB_FATSz32;
    fsbi->sec_per_FAT = fbs->BPB_FATSz32;
    fsbi->NumFATs = fbs->BPB_NumFATs;
    fsbi->fsinfo_sector_addr_infat = fbs->BPB_FSInfo;
    fsbi->bootsector_bak_sector_addr_infat = fbs->BPB_BkBootSec;

    printk_color(ORANGE, BLACK, "FAT32 Boot Sector\n\tBPB_FSInfo:%#018lx\n\tBPB_BkBootSec:%#018lx\n\tBPB_TotSec32:%#018lx\n", fbs->BPB_FSInfo, fbs->BPB_BkBootSec, fbs->BPB_TotSec32);

    // fsinfo扇区的信息
    memset(&fsbi->fsinfo, 0, sizeof(struct fat32_FSInfo_t));
    ahci_operation.transfer(ATA_CMD_READ_DMA_EXT, MBR_DPTE->starting_LBA + fbs->BPB_FSInfo, 1, (uint64_t)&fsbi->fsinfo, ahci_ctrl_num, ahci_port_num);
    printk_color(BLUE, BLACK, "FAT32 FSInfo\n\tFSI_LeadSig:%#018lx\n\tFSI_StrucSig:%#018lx\n\tFSI_Free_Count:%#018lx\n", fsbi->fsinfo.FSI_LeadSig, fsbi->fsinfo.FSI_StrucSig, fsbi->fsinfo.FSI_Free_Count);

    // 初始化超级块的dir entry
    sb_ptr->root = (struct vfs_dir_entry_t *)kmalloc(sizeof(struct vfs_dir_entry_t), 0);
    memset(sb_ptr->root, 0, sizeof(struct vfs_dir_entry_t));

    list_init(&sb_ptr->root->child_node_list);
    list_init(&sb_ptr->root->subdirs_list);

    sb_ptr->root->parent = sb_ptr->root;
    sb_ptr->root->dir_ops = &fat32_dEntry_ops;
    // 分配2个字节的name
    sb_ptr->root->name = (char *)(kmalloc(2, 0));
    sb_ptr->root->name[0] = '/';
    sb_ptr->root->name_length = 1;

    // 为root目录项分配index node
    sb_ptr->root->dir_inode = (struct vfs_index_node_t *)kmalloc(sizeof(struct vfs_index_node_t), 0);
    memset(sb_ptr->root->dir_inode, 0, sizeof(struct vfs_index_node_t));
    sb_ptr->root->dir_inode->inode_ops = &fat32_inode_ops;
    sb_ptr->root->dir_inode->file_ops = &fat32_file_ops;
    sb_ptr->root->dir_inode->file_size = 0;
    // 计算文件占用的扇区数, 由于最小存储单位是簇，因此需要按照簇的大小来对齐扇区
    sb_ptr->root->dir_inode->blocks = (sb_ptr->root->dir_inode->file_size + fsbi->bytes_per_clus - 1) / fsbi->bytes_per_sec;
    sb_ptr->root->dir_inode->attribute = VFS_ATTR_DIR;
    sb_ptr->root->dir_inode->sb = sb_ptr; // 反向绑定对应的超级块

    // 初始化inode信息
    sb_ptr->root->dir_inode->private_inode_info = kmalloc(sizeof(struct fat32_inode_info_t), 0);
    memset(sb_ptr->root->dir_inode->private_inode_info, 0, sizeof(struct fat32_inode_info_t));
    struct fat32_inode_info_t *finode = (struct fat32_inode_info_t *)sb_ptr->root->dir_inode->private_inode_info;

    finode->first_clus = fbs->BPB_RootClus;
    finode->dEntry_location_clus = 0;
    finode->dEntry_location_clus_offset = 0;
    finode->create_time = 0;
    finode->create_date = 0;
    finode->write_date = 0;
    finode->write_time;

    return sb_ptr;
}

/**
 * @brief todo: 写入superblock
 *
 * @param sb
 */
void fat32_write_superblock(struct vfs_superblock_t *sb)
{
}

/**
 * @brief 释放superblock的内存空间
 *
 * @param sb 要被释放的superblock
 */
void fat32_put_superblock(struct vfs_superblock_t *sb)
{
    kfree(sb->private_sb_info);
    kfree(sb->root->dir_inode->private_inode_info);
    kfree(sb->root->dir_inode);
    kfree(sb->root);
    kfree(sb);
}

/**
 * @brief 写入inode到硬盘上
 *
 * @param inode
 */
void fat32_write_inode(struct vfs_index_node_t *inode)
{
    fat32_inode_info_t *finode = inode->private_inode_info;

    if (finode->dEntry_location_clus == 0)
    {
        kerror("FAT32 error: Attempt to write the root inode");
        return;
    }

    fat32_sb_info_t *fsbi = (fat32_sb_info_t *)inode->sb->private_sb_info;

    // 计算目标inode对应数据区的LBA地址
    uint64_t fLBA = fsbi->first_data_sector + (finode->dEntry_location_clus - 2) * fsbi->sec_per_clus;

    uint8_t *buf = (uint8_t *)kmalloc(fsbi->bytes_per_clus, 0);
    memset(buf, 0, sizeof(fsbi->bytes_per_clus));
    ahci_operation.transfer(ATA_CMD_READ_DMA_EXT, fLBA, fsbi->sec_per_clus, (uint64_t)buf, fsbi->ahci_ctrl_num, fsbi->ahci_port_num);

    // 计算目标dEntry所在的位置
    struct fat32_Directory_t *fdEntry = (struct fat32_Directory_t *)((uint64_t)buf + finode->dEntry_location_clus_offset);

    // 写入fat32文件系统的dir_entry
    fdEntry->DIR_FileSize = inode->file_size;
    fdEntry->DIR_FstClusLO = finode->first_clus & 0xffff;
    fdEntry->DIR_FstClusHI = (finode->first_clus >> 16) | (fdEntry->DIR_FstClusHI & 0xf000);

    // 将dir entry写回磁盘
    ahci_operation.transfer(ATA_CMD_WRITE_DMA_EXT, fLBA, fsbi->sec_per_clus, (uint64_t)buf, fsbi->ahci_ctrl_num, fsbi->ahci_port_num);

    kfree(buf);
}

struct vfs_super_block_operations_t fat32_sb_ops =
    {
        .write_superblock = fat32_write_superblock,
        .put_superblock = fat32_put_superblock,
        .write_inode = fat32_write_inode,
};

// todo: compare
long fat32_compare(struct vfs_dir_entry_t *parent_dEntry, char *source_filename, char *dest_filename)
{
}
// todo: hash
long fat32_hash(struct vfs_dir_entry_t *dEntry, char *filename)
{
}
// todo: release
long fat32_release(struct vfs_dir_entry_t *dEntry)
{
}
// todo: iput
long fat32_iput(struct vfs_dir_entry_t *dEntry, struct vfs_index_node_t *inode)
{
}

/**
 * @brief fat32文件系统对于dEntry的操作
 *
 */
struct vfs_dir_entry_operations_t fat32_dEntry_ops =
    {
        .compare = fat32_compare,
        .hash = fat32_hash,
        .release = fat32_release,
        .iput = fat32_iput,
};

// todo: open
long fat32_open(struct vfs_index_node_t *inode, struct vfs_file_t *file_ptr)
{
}

// todo: close
long fat32_close(struct vfs_index_node_t *inode, struct vfs_file_t *file_ptr)
{
}

// todo: read
long fat32_read(struct vfs_file_t *file_ptr, char *buf, uint64_t buf_size, long *position)
{
}
// todo: write
long fat32_write(struct vfs_file_t *file_ptr, char *buf, uint64_t buf_size, long *position)
{
}
// todo: lseek
long fat32_lseek(struct vfs_file_t *file_ptr, long offset, long origin)
{
}
// todo: ioctl
long fat32_ioctl(struct vfs_index_node_t *inode, struct vfs_file_t *file_ptr, uint64_t cmd, uint64_t arg)
{
}

/**
 * @brief fat32文件系统，关于文件的操作
 *
 */
struct vfs_file_operations_t fat32_file_ops =
    {
        .open = fat32_open,
        .close = fat32_close,
        .read = fat32_read,
        .write = fat32_write,
        .lseek = fat32_lseek,
        .ioctl = fat32_ioctl,
};

// todo: create
long fat32_create(struct vfs_index_node_t *inode, struct vfs_dir_entry_t *dentry, int mode)
{
}

// todo: mkdir
int64_t fat32_mkdir(struct vfs_index_node_t *inode, struct vfs_dir_entry_t *dEntry, int mode)
{
}

// todo: rmdir
int64_t fat32_rmdir(struct vfs_index_node_t *inode, struct vfs_dir_entry_t *dEntry)
{
}

// todo: rename
int64_t fat32_rename(struct vfs_index_node_t *old_inode, struct vfs_dir_entry_t *old_dEntry, struct vfs_index_node_t *new_inode, struct vfs_dir_entry_t *new_dEntry)
{
}

// todo: getAttr
int64_t fat32_getAttr(struct vfs_dir_entry_t *dEntry, uint64_t *attr)
{
}

// todo: setAttr
int64_t fat32_setAttr(struct vfs_dir_entry_t *dEntry, uint64_t *attr)
{
}

struct vfs_inode_operations_t fat32_inode_ops =
    {
        .create = fat32_create,
        .mkdir = fat32_mkdir,
        .rmdir = fat32_rmdir,
        .lookup = fat32_lookup,
        .rename = fat32_rename,
        .getAttr = fat32_getAttr,
        .setAttr = fat32_setAttr,

};

struct vfs_filesystem_type_t fat32_fs_type = 
{
    .name = "FAT32",
    .fs_flags = 0,
    .read_superblock = fat32_read_superblock,
    .next = NULL,
};
void fat32_init()
{

   // kinfo("Initializing FAT32...");

    // 在VFS中注册fat32文件系统
    vfs_register_filesystem(&fat32_fs_type);

    // 挂载根文件系统
    vfs_root_sb = fat32_register_partition(0, 0, 0);
}