Disk

Disk 的协作图:

函数
INT32	los_disk_init (const CHAR *diskName, const struct block_operations *bops, VOID *priv, INT32 diskID, VOID *info)
	Disk driver initialization. 更多...
INT32	los_disk_deinit (INT32 diskID)
	Destroy a disk driver. 更多...
INT32	los_disk_read (INT32 drvID, VOID *buf, UINT64 sector, UINT32 count, BOOL useRead)
	Read data from disk driver. 更多...
INT32	los_disk_write (INT32 drvID, const VOID *buf, UINT64 sector, UINT32 count)
	Write data to a disk driver. 更多...
INT32	los_disk_ioctl (INT32 drvID, INT32 cmd, VOID *buf)
	Get information of disk driver. 更多...
INT32	los_disk_sync (INT32 drvID)
	Sync blib cache. 更多...
INT32	los_disk_set_bcache (INT32 drvID, UINT32 sectorPerBlock, UINT32 blockNum)
	Set blib cache for the disk driver. 更多...
INT32	los_part_read (INT32 pt, VOID *buf, UINT64 sector, UINT32 count, BOOL useRead)
	Read data from chosen partition. 更多...
INT32	los_part_write (INT32 pt, const VOID *buf, UINT64 sector, UINT32 count)
	Write data to chosen partition. 更多...
INT32	los_disk_cache_clear (INT32 drvID)
	Clear the bcache data 更多...
INT32	los_part_ioctl (INT32 pt, INT32 cmd, VOID *buf)
	Get information of chosen partition. 更多...
INT32	los_part_access (const CHAR *dev, mode_t mode)
	Decide the chosen partition is exist or not. 更多...
los_part *	los_part_find (struct Vnode *blkDriver)
	Find disk partition. 更多...
los_disk *	get_disk (INT32 id)
	Find disk driver. 更多...
los_part *	get_part (INT32 id)
	Find disk partition. 更多...
VOID	show_part (los_part *part)
	Print partition information. 更多...
INT32	add_mmc_partition (struct disk_divide_info *info, size_t sectorStart, size_t sectorCount)
	Add a new mmc partition. 更多...
INT32	los_alloc_diskid_byname (const CHAR *diskName)
	alloc a new UNUSED disk id. 更多...
INT32	los_get_diskid_byname (const CHAR *diskName)
	get the INUSED disk id. 更多...
VOID	OsSetUsbStatus (UINT32 diskId)
	Set usb mode. 更多...
VOID	OsClearUsbStatus (UINT32 diskId)
	Set usb mode. 更多...

详细描述

函数说明

add_mmc_partition()

INT32 add_mmc_partition	(	struct disk_divide_info *	info,
		size_t	sectorStart,
		size_t	sectorCount
	)

Add a new mmc partition.

Description:

Add a new mmc partition, users can set the start sector and size of the new partition.

注意

参数

info	[IN] Type #struct disk_divide_info * Disk driver information structure pointer.
sectorStart	[IN] Type size_t Start sector number of the new partition.
sectorCount	[IN] Type size_t Sector count of the new partition.

返回值

#0	Add partition success.
#-1	Add partition failed.

Dependency:

• disk.h

参见

None

Add a new mmc partition.

参数

info
sectorStart
sectorCount

返回

INT32

在文件 disk.c 第 1779 行定义.

{
    UINT32 index, i;
 
    if (info == NULL) {
        return VFS_ERROR;
    }
    //磁盘判断
    if ((info->part_count >= MAX_DIVIDE_PART_PER_DISK) || (sectorCount == 0)) {
        return VFS_ERROR;
    }
    //扇区判断
    if ((sectorCount > info->sector_count) || ((info->sector_count - sectorCount) < sectorStart)) {
        return VFS_ERROR;
    }
 
    index = info->part_count;
    for (i = 0; i < index; i++) {//验证目的是确保分区的顺序,扇区顺序从小到大排列
        if (sectorStart < (info->part[i].sector_start + info->part[i].sector_count)) {
            return VFS_ERROR;
        }
    }
 
    info->part[index].sector_start = sectorStart;//开始扇区
    info->part[index].sector_count = sectorCount;//扇区总数
    info->part[index].type = EMMC;//分区类型
    info->part_count++;//分区数量增加,鸿蒙分区数量上限默认是80个.
 
    return ENOERR;
}

这是这个函数的调用关系图:

get_disk()

los_disk * get_disk

(

INT32

id

)

Find disk driver.

Description:

By disk driver id number to find disk dirver.

注意

参数

id	[IN] Type INT32 disk id number,less than the value defined by SYS_MAX_DISK.

返回值

#NULL	Can't find chosen disk driver.
los_disk	* This is disk structure pointer of chosen disk driver.

Dependency:

• disk.h

参见

None

在文件 disk.c 第 263 行定义.

{
    if ((id >= 0) && (id < SYS_MAX_DISK)) {
        return &g_sysDisk[id];
    }
 
    return NULL;
}

这是这个函数的调用关系图:

get_part()

los_part * get_part

(

INT32

id

)

Find disk partition.

Description:

By driver partition id number to find disk partition.

注意

参数

id	[IN] Type INT32 partition id number,less than the value defined by SYS_MAX_PART.

返回值

#NULL	Can't find chosen disk partition.
los_part	* This is partition structure pointer of chosen disk partition.

Dependency:

• disk.h

参见

None

Find disk partition.

在文件 disk.c 第 272 行定义.

{
    if ((id >= 0) && (id < SYS_MAX_PART)) {
        return &g_sysPart[id];
    }
 
    return NULL;
}

这是这个函数的调用关系图:

los_alloc_diskid_byname()

INT32 los_alloc_diskid_byname

(

const CHAR *

diskName

)

alloc a new UNUSED disk id.

Description:

Get a free disk id for new device.

注意

• The parameter diskName must point a valid string, which end with the null byte ('\0')
• The total length of parameter diskName must be less than the value defined by DISK_NAME

参数

diskName

[IN] Type #const CHAR * device name.

返回值

INT32	available disk id
#-1	alloc disk id failed

Dependency:

• disk.h

参见

los_get_diskid_byname

alloc a new UNUSED disk id.

在文件 disk.c 第 134 行定义.

{
    INT32 diskID;
    los_disk *disk = NULL;
    UINT32 intSave;
    size_t nameLen;
 
    if (diskName == NULL) {
        PRINT_ERR("The parameter disk_name is NULL");
        return VFS_ERROR;
    }
 
    nameLen = strlen(diskName);
    if (nameLen > DISK_NAME) {
        PRINT_ERR("diskName is too long!\n");
        return VFS_ERROR;
    }
    spin_lock_irqsave(&g_diskSpinlock, intSave);//加锁
 
    for (diskID = 0; diskID < SYS_MAX_DISK; diskID++) {//磁盘池中分配一个磁盘描述符
        disk = get_disk(diskID);
        if ((disk != NULL) && (disk->disk_status == STAT_UNUSED)) {
            disk->disk_status = STAT_UNREADY;//初始状态,可理解为未格式化
            break;
        }
    }
 
    spin_unlock_irqrestore(&g_diskSpinlock, intSave);
 
    if ((disk == NULL) || (diskID == SYS_MAX_DISK)) {
        PRINT_ERR("los_alloc_diskid_byname failed %d!\n", diskID);
        return VFS_ERROR;
    }
 
    if (disk->disk_name != NULL) {//分配的磁盘如果有名称,可能之前用过,先释放内核内存
        LOS_MemFree(m_aucSysMem0, disk->disk_name);
        disk->disk_name = NULL;
    }
 
    disk->disk_name = LOS_MemAlloc(m_aucSysMem0, (nameLen + 1));
    if (disk->disk_name == NULL) {
        PRINT_ERR("los_alloc_diskid_byname alloc disk name failed\n");
        return VFS_ERROR;
    }
    //disk->disk_name 等于 参数 名称
    if (strncpy_s(disk->disk_name, (nameLen + 1), diskName, nameLen) != EOK) {
        PRINT_ERR("The strncpy_s failed.\n");
        LOS_MemFree(m_aucSysMem0, disk->disk_name);
        disk->disk_name = NULL;
        return VFS_ERROR;
    }
 
    disk->disk_name[nameLen] = '\0';
 
    return diskID;
}

函数调用图:

这是这个函数的调用关系图:

los_disk_cache_clear()

INT32 los_disk_cache_clear

(

INT32

drvID

)

Clear the bcache data

Description:

Flush the data and mark the block as unused.

注意

参数

drvID

[IN] Type INT32 disk id

返回值

#0	Write success.
#-1	Write failed.

Dependency:

• disk.h

参见

los_part_read

在文件 disk.c 第 1254 行定义.

{
    INT32 result = ENOERR;
#ifdef LOSCFG_FS_FAT_CACHE
    los_part *part = get_part(drvID);
    los_disk *disk = NULL;
 
    if (part == NULL) {
        return VFS_ERROR;
    }
    result = OsSdSync(part->disk_id);
    if (result != ENOERR) {
        PRINTK("[ERROR]disk_cache_clear SD sync failed!\n");
        return result;
    }
 
    disk = get_disk(part->disk_id);
    if (disk == NULL) {
        return VFS_ERROR;
    }
 
    DISK_LOCK(&disk->disk_mutex);
    result = BcacheClearCache(disk->bcache);
    DISK_UNLOCK(&disk->disk_mutex);
#endif
    return result;
}

函数调用图:

los_disk_deinit()

INT32 los_disk_deinit

(

INT32

diskID

)

Destroy a disk driver.

Description:

Destroy a disk driver, free the dependent resource.

注意

参数

diskID

[IN] Type INT32 disk driver id number, less than the value defined by SYS_MAX_DISK.

返回值

#0	Destroy success.
#-1	Destroy failed.

Dependency:

• disk.h

参见

los_disk_init

Destroy a disk driver.

在文件 disk.c 第 1544 行定义.

{
    int ret;
    los_disk *disk = get_disk(diskID);
    if (disk == NULL) {
        return -EINVAL;
    }
    ret = ForceUmountDev(disk->dev);
    PRINTK("warning: %s lost, force umount ret = %d\n", disk->disk_name, ret);
 
    DISK_LOCK(&disk->disk_mutex);
 
    if (disk->disk_status != STAT_INUSED) {
        DISK_UNLOCK(&disk->disk_mutex);
        return -EINVAL;
    }
 
    disk->disk_status = STAT_UNREADY;//未格式化状态
    DISK_UNLOCK(&disk->disk_mutex);
 
    return DiskDeinit(disk);
}

函数调用图:

这是这个函数的调用关系图:

los_disk_init()

INT32 los_disk_init	(	const CHAR *	diskName,
		const struct block_operations *	bops,
		VOID *	priv,
		INT32	diskID,
		VOID *	info
	)

Disk driver initialization.

Description:

Initializate a disk dirver, and set the block cache.

注意

• The parameter diskName must point a valid string, which end with the terminating null byte.
• The total length of parameter diskName must be less than the value defined by PATH_MAX.
• The parameter bops must pointed the right functions, otherwise the system will crash when the disk is being operated.
• The parameter info can be null or point to struct disk_divide_info. when info is null, the disk will be divided base the information of MBR, otherwise, the disk will be divided base the information of parameter info.

参数

diskName	[IN] Type #const CHAR * disk driver name.
bops	[IN] Type #const struct block_operations * block driver control structure.
priv	[IN] Type #VOID * private data of vnode.
diskID	[IN] Type INT32 disk id number, less than SYS_MAX_DISK.
info	[IN] Type #VOID * disk driver partition information.

返回值

#0	Initialization success.
#-1	Initialization failed.

Dependency:

• disk.h

参见

los_disk_deinit

Disk driver initialization.

在文件 disk.c 第 1481 行定义.

{
    struct geometry diskInfo;
    struct Vnode *blkDriver = NULL;
    los_disk *disk = get_disk(diskID);
    INT32 ret;
    //参数检查
    if ((diskName == NULL) || (disk == NULL) ||
        (disk->disk_status != STAT_UNREADY) || (strlen(diskName) > DISK_NAME)) {
        return VFS_ERROR;
    }
    //注册块设备驱动,设备驱动程序由设备提供
    if (register_blockdriver(diskName, bops, RWE_RW_RW, priv) != 0) {
        PRINT_ERR("disk_init : register %s fail!\n", diskName);
        return VFS_ERROR;
    }
 
    VnodeHold();
    ret = VnodeLookup(diskName, &blkDriver, 0);
    if (ret < 0) {
        VnodeDrop();
        ret = ENOENT;
        goto DISK_FIND_ERROR;
    }
    struct block_operations *bops2 = (struct block_operations *)((struct drv_data *)blkDriver->data)->ops;
    //块操作,块是文件系统层面的概念,块（Block）是文件系统存取数据的最小单位，一般大小是4KB
    if ((bops2 == NULL) || (bops2->geometry == NULL) || (bops2->geometry(blkDriver, &diskInfo) != 0)) {
        goto DISK_BLKDRIVER_ERROR;
    }
 
    if (diskInfo.geo_sectorsize < DISK_MAX_SECTOR_SIZE) {
        goto DISK_BLKDRIVER_ERROR;
    }
 
    ret = OsDiskInitSub(diskName, diskID, disk, &diskInfo, blkDriver);
    if (ret != ENOERR) {
        (VOID)DiskDeinit(disk);
        VnodeDrop();
        return VFS_ERROR;
    }
    VnodeDrop();
    if (DiskDivideAndPartitionRegister(info, disk) != ENOERR) {
        (VOID)DiskDeinit(disk);
        return VFS_ERROR;
    }
 
    disk->disk_status = STAT_INUSED;//磁盘状态变成使用中
    if (info != NULL) {//https://www.huaweicloud.com/articles/bcdefd0d9da5de83d513123ef3aabcf0.html
        disk->type = EMMC;//eMMC 是 embedded MultiMediaCard 的简称
    } else {
        disk->type = OTHERS;
    }
    return ENOERR;
 
DISK_BLKDRIVER_ERROR:
    PRINT_ERR("disk_init : register %s ok but get disk info fail!\n", diskName);
    VnodeDrop();
DISK_FIND_ERROR:
    (VOID)unregister_blockdriver(diskName);//注销块设备驱动
    return VFS_ERROR;
}

函数调用图:

这是这个函数的调用关系图:

los_disk_ioctl()

INT32 los_disk_ioctl	(	INT32	drvID,
		INT32	cmd,
		VOID *	buf
	)

Get information of disk driver.

Description:

Get information of disk driver.

注意

参数

drvID	[IN] Type INT32 disk driver id number, less than the value defined by SYS_MAX_DISK.
cmd	[IN] Type INT32 command to issu, currently support GET_SECTOR_COUNT, GET_SECTOR_SIZE, GET_BLOCK_SIZE, CTRL_SYNC.
buf	[OUT] Type #VOID * memory to storage the information, the size must enough for data type(UINT64) when cmd type is DISK_GET_SECTOR_COUNT, others is size_t.

返回值

#0	Get information success.
#-1	Get information failed.

Dependency:

• disk.h

参见

None

在文件 disk.c 第 1027 行定义.

{
    struct geometry info;
    los_disk *disk = get_disk(drvID);
    if (disk == NULL) {
        return VFS_ERROR;
    }
 
    DISK_LOCK(&disk->disk_mutex);
 
    if ((disk->dev == NULL) || (disk->disk_status != STAT_INUSED)) {
        goto ERROR_HANDLE;
    }
 
    if (cmd == DISK_CTRL_SYNC) {
        DISK_UNLOCK(&disk->disk_mutex);
        return ENOERR;
    }
 
    if (buf == NULL) {
        goto ERROR_HANDLE;
    }
 
    (VOID)memset_s(&info, sizeof(info), 0, sizeof(info));
 
    struct block_operations *bops = (struct block_operations *)((struct drv_data *)disk->dev->data)->ops;
    if ((bops == NULL) || (bops->geometry == NULL) ||
        (bops->geometry(disk->dev, &info) != 0)) {
        goto ERROR_HANDLE;
    }
 
    if (cmd == DISK_GET_SECTOR_COUNT) {
        *(UINT64 *)buf = info.geo_nsectors;
        if (info.geo_nsectors == 0) {
            goto ERROR_HANDLE;
        }
    } else if (cmd == DISK_GET_SECTOR_SIZE) {
        *(size_t *)buf = info.geo_sectorsize;
    } else if (cmd == DISK_GET_BLOCK_SIZE) { /* Get erase block size in unit of sectors (UINT32) */
        /* Block Num SDHC == 512, SD can be set to 512 or other */
        *(size_t *)buf = DISK_MAX_SECTOR_SIZE / info.geo_sectorsize;
    } else {
        goto ERROR_HANDLE;
    }
 
    DISK_UNLOCK(&disk->disk_mutex);
    return ENOERR;
 
ERROR_HANDLE:
    DISK_UNLOCK(&disk->disk_mutex);
    return VFS_ERROR;
}

函数调用图:

los_disk_read()

INT32 los_disk_read	(	INT32	drvID,
		VOID *	buf,
		UINT64	sector,
		UINT32	count,
		BOOL	useRead
	)

Read data from disk driver.

Description:

Read data from disk driver.

注意

• The sector size of the disk to be read should be acquired by los_part_ioctl before calling this function.
• The parameter buf must point to a valid memory and the buf size is count * sector_size.

参数

drvID	[IN] Type INT32 disk driver id number, less than the value defined by SYS_MAX_DISK.
buf	[OUT] Type #VOID * memory which used to store read data.
sector	[IN] Type UINT64 expected start sector number to read.
count	[IN] Type UINT32 expected sector count to read.
useRead	[IN] Type BOOL set FALSE to use the write block for optimization

返回值

#0	Read success.
#-1	Read failed.

Dependency:

• disk.h

参见

los_disk_write

Read data from disk driver.

在文件 disk.c 第 911 行定义.

{
#ifdef LOSCFG_FS_FAT_CACHE
    UINT32 len;
#endif
    INT32 result = VFS_ERROR;
    los_disk *disk = get_disk(drvID);
 
    if ((buf == NULL) || (count == 0)) { /* buff equal to NULL or count equal to 0 */
        return result;
    }
 
    if (disk == NULL) {
        return result;
    }
 
    DISK_LOCK(&disk->disk_mutex);
 
    if (disk->disk_status != STAT_INUSED) {
        goto ERROR_HANDLE;
    }
 
    if ((count > disk->sector_count) || ((disk->sector_count - count) < sector)) {
        goto ERROR_HANDLE;
    }
 
#ifdef LOSCFG_FS_FAT_CACHE
    if (disk->bcache != NULL) {
        if (((UINT64)(disk->bcache->sectorSize) * count) > UINT_MAX) {
            goto ERROR_HANDLE;
        }
        len = disk->bcache->sectorSize * count;
        /* useRead should be FALSE when reading large contiguous data *///读取大量连续数据时，useRead 应为 FALSE
        result = BlockCacheRead(disk->bcache, (UINT8 *)buf, &len, sector, useRead);//从缓存区里读
        if (result != ENOERR) {
            PRINT_ERR("los_disk_read read err = %d, sector = %llu, len = %u\n", result, sector, len);
        }
    } else {
        result = VFS_ERROR;
    }
#else
    if (disk->dev == NULL) {
        goto ERROR_HANDLE;
    }
    result = disk_read_directly(disk, buf, sector, count);
#endif
 
    if (result != ENOERR) {
        goto ERROR_HANDLE;
    }
 
    DISK_UNLOCK(&disk->disk_mutex);
    return ENOERR;
 
ERROR_HANDLE:
    DISK_UNLOCK(&disk->disk_mutex);
    return VFS_ERROR;
}

函数调用图:

这是这个函数的调用关系图:

los_disk_set_bcache()

INT32 los_disk_set_bcache	(	INT32	drvID,
		UINT32	sectorPerBlock,
		UINT32	blockNum
	)

Set blib cache for the disk driver.

Description:

Set blib cache for the disk driver, users can set the number of sectors of per block, and the number of blocks.

注意

参数

drvID	[IN] Type INT32 disk driver id number, less than the value defined by SYS_MAX_DISK.
sectorPerBlock	[IN] Type UINT32 sector number of per block, only can be 32 * (1, 2, ..., 8).
blockNum	[IN] Type UINT32 block number of cache.

返回值

#0	Set success.
INT32	Set failed.

Dependency:

• disk.h

参见

None

Set blib cache for the disk driver.

在文件 disk.c 第 1591 行定义.

{
#ifdef LOSCFG_FS_FAT_CACHE
 
    INT32 ret;
    UINT32 intSave;
    OsBcache *bc = NULL;
    los_disk *disk = get_disk(drvID);
    if ((disk == NULL) || (sectorPerBlock == 0)) {
        return EINVAL;
    }
 
    /*
     * Because we use UINT32 flag[BCACHE_BLOCK_FLAGS] in bcache for sectors bitmap tag, so it must
     * be less than 32 * BCACHE_BLOCK_FLAGS.
     */
    if (((sectorPerBlock % UNSIGNED_INTEGER_BITS) != 0) ||
        ((sectorPerBlock >> UNINT_LOG2_SHIFT) > BCACHE_BLOCK_FLAGS)) {
        return EINVAL;
    }
 
    DISK_LOCK(&disk->disk_mutex);
 
    if (disk->disk_status != STAT_INUSED) {
        goto ERROR_HANDLE;
    }
 
    if (disk->bcache != NULL) {
        ret = BlockCacheSync(disk->bcache);
        if (ret != ENOERR) {
            DISK_UNLOCK(&disk->disk_mutex);
            return ret;
        }
    }
 
    spin_lock_irqsave(&g_diskFatBlockSpinlock, intSave);
    DiskCacheDeinit(disk);
 
    g_uwFatBlockNums = blockNum;
    g_uwFatSectorsPerBlock = sectorPerBlock;
 
    bc = BlockCacheInit(disk->dev, disk->sector_size, sectorPerBlock, blockNum, disk->sector_count / sectorPerBlock);
    if ((bc == NULL) && (blockNum != 0)) {
        spin_unlock_irqrestore(&g_diskFatBlockSpinlock, intSave);
        DISK_UNLOCK(&disk->disk_mutex);
        return ENOMEM;
    }
 
    if (bc != NULL) {
        DiskCacheThreadInit((UINT32)drvID, bc);
    }
 
    disk->bcache = bc;
    spin_unlock_irqrestore(&g_diskFatBlockSpinlock, intSave);
    DISK_UNLOCK(&disk->disk_mutex);
    return ENOERR;
 
ERROR_HANDLE:
    DISK_UNLOCK(&disk->disk_mutex);
    return EINVAL;
#else
    return VFS_ERROR;
#endif
}

函数调用图:

los_disk_sync()

INT32 los_disk_sync

(

INT32

drvID

)

Sync blib cache.

Description:

Sync blib cache, write the valid data to disk driver.

注意

参数

drvID

[IN] Type INT32 disk driver id number, less than the value defined by SYS_MAX_DISK.

返回值

#0	Sync success.
INT32	Sync failed.

Dependency:

• disk.h

参见

None

Sync blib cache.

在文件 disk.c 第 1567 行定义.

{
    INT32 ret = ENOERR;
    los_disk *disk = get_disk(drvID);
    if (disk == NULL) {
        return EINVAL;
    }
 
    DISK_LOCK(&disk->disk_mutex);
    if (disk->disk_status != STAT_INUSED) {
        DISK_UNLOCK(&disk->disk_mutex);
        return EINVAL;
    }
 
#ifdef LOSCFG_FS_FAT_CACHE
        if (disk->bcache != NULL) {
            ret = BlockCacheSync(disk->bcache);
        }
#endif
 
    DISK_UNLOCK(&disk->disk_mutex);
    return ret;
}

函数调用图:

los_disk_write()

INT32 los_disk_write	(	INT32	drvID,
		const VOID *	buf,
		UINT64	sector,
		UINT32	count
	)

Write data to a disk driver.

Description:

Write data to a disk driver.

注意

• The sector size of the disk to be read should be acquired by los_part_ioctl before calling this function.
• The parameter buf must point to a valid memory and the buf size is count * sector_size.

参数

drvID	[IN] Type INT32 disk driver id number, less than the value defined by SYS_MAX_DISK.
buf	[IN] Type #const VOID * memory which used to storage write data.
sector	[IN] Type UINT64 expected start sector number to read.
count	[IN] Type UINT32 experted sector count of write.

返回值

#0	Write success.
#-1	Write failed.

Dependency:

• disk.h

参见

los_disk_read

Write data to a disk driver.

在文件 disk.c 第 970 行定义.

{
#ifdef LOSCFG_FS_FAT_CACHE
    UINT32 len;
#endif
    INT32 result = VFS_ERROR;
    los_disk *disk = get_disk(drvID);
    if (disk == NULL || disk->dev == NULL || disk->dev->data == NULL) {
        return result;
    }
 
    if ((buf == NULL) || (count == 0)) { /* buff equal to NULL or count equal to 0 */
        return result;
    }
 
    DISK_LOCK(&disk->disk_mutex);
 
    if (disk->disk_status != STAT_INUSED) {
        goto ERROR_HANDLE;
    }
 
    if ((count > disk->sector_count) || ((disk->sector_count - count) < sector)) {
        goto ERROR_HANDLE;
    }
 
#ifdef LOSCFG_FS_FAT_CACHE
    if (disk->bcache != NULL) {
        if (((UINT64)(disk->bcache->sectorSize) * count) > UINT_MAX) {
            goto ERROR_HANDLE;
        }
        len = disk->bcache->sectorSize * count;
        result = BlockCacheWrite(disk->bcache, (const UINT8 *)buf, &len, sector);//写入缓存,后续由缓存同步至磁盘
        if (result != ENOERR) {
            PRINT_ERR("los_disk_write write err = %d, sector = %llu, len = %u\n", result, sector, len);
        }
    } else {
        result = VFS_ERROR;
    }
#else
    if (disk->dev == NULL) {
        goto ERROR_HANDLE;
    }
    result = disk_write_directly(disk, buf, sector, count);
#endif
 
    if (result != ENOERR) {
        goto ERROR_HANDLE;
    }
 
    DISK_UNLOCK(&disk->disk_mutex);
    return ENOERR;
 
ERROR_HANDLE:
    DISK_UNLOCK(&disk->disk_mutex);
    return VFS_ERROR;
}

函数调用图:

这是这个函数的调用关系图:

los_get_diskid_byname()

INT32 los_get_diskid_byname

(

const CHAR *

diskName

)

get the INUSED disk id.

Description:

Get the corresponding INUSED disk id by diskName.

注意

• The parameter diskName must point a valid string, which end with the null byte ('\0')
• The total length of parameter diskName must be less than the value defined by DISK_NAME

参数

diskName

[IN] Type #const CHAR * device name.

返回值

INT32	available disk id
#-1	get disk id failed

Dependency:

• disk.h

参见

los_alloc_diskid_byname

get the INUSED disk id.

在文件 disk.c 第 191 行定义.

{
    INT32 diskID;
    los_disk *disk = NULL;
    size_t diskNameLen;
 
    if (diskName == NULL) {
        PRINT_ERR("The parameter diskName is NULL");
        return VFS_ERROR;
    }
 
    diskNameLen = strlen(diskName);
    if (diskNameLen > DISK_NAME) {
        PRINT_ERR("diskName is too long!\n");
        return VFS_ERROR;
    }
 
    for (diskID = 0; diskID < SYS_MAX_DISK; diskID++) {
        disk = get_disk(diskID);
        if ((disk != NULL) && (disk->disk_name != NULL) && (disk->disk_status == STAT_INUSED)) {
            if (strlen(disk->disk_name) != diskNameLen) {
                continue;
            }
            if (strcmp(diskName, disk->disk_name) == 0) {
                break;
            }
        }
    }
    if ((disk == NULL) || (diskID == SYS_MAX_DISK)) {
        PRINT_ERR("los_get_diskid_byname failed!\n");
        return VFS_ERROR;
    }
    return diskID;
}

函数调用图:

这是这个函数的调用关系图:

los_part_access()

INT32 los_part_access	(	const CHAR *	dev,
		mode_t	mode
	)

Decide the chosen partition is exist or not.

Description:

Decide the chosen partition is exist or not.

注意

• The parameter dev is a full path, which begin with '/' and end with '/0'.

参数

dev	[IN] Type #const CHAR * partition driver name.
mode	[IN] Type mode_t access modd.

返回值

#0	The chosen partition is exist.
#-1	The chosen partition is not exist.

Dependency:

• disk.h

参见

None

Decide the chosen partition is exist or not.

在文件 disk.c 第 1706 行定义.

{
    los_part *part = NULL;
    struct Vnode *node = NULL;
 
    VnodeHold();
    if (VnodeLookup(dev, &node, 0) < 0) {
        VnodeDrop();
        return VFS_ERROR;
    }
 
    part = los_part_find(node);//通过节点找到分区
    VnodeDrop();
    if (part == NULL) {
        return VFS_ERROR;
    }
 
    return ENOERR;
}

函数调用图:

los_part_find()

los_part * los_part_find

(

struct Vnode *

blkDriver

)

Find disk partition.

Description:

By driver partition vnode to find disk partition.

注意

参数

blkDriver

[IN] Type #struct Vnode * partition driver vnode.

返回值

#NULL	Can't find chosen disk partition.
los_part	* This is partition structure pointer of chosen disk partition.

Dependency:

• disk.h

参见

None

Find disk partition.

在文件 disk.c 第 1682 行定义.

{
    INT32 i;
    los_disk *disk = NULL;
    los_part *part = NULL;
 
    if (blkDriver == NULL) {
        return NULL;
    }
 
    for (i = 0; i < SYS_MAX_DISK; i++) {//遍历所有磁盘
        disk = get_disk(i);
        if (disk == NULL) {
            continue;
        }
        part = OsPartFind(disk, blkDriver);//从磁盘中通过节点找分区信息
        if (part != NULL) {
            return part;
        }
    }
 
    return NULL;
}

函数调用图:

这是这个函数的调用关系图:

los_part_ioctl()

INT32 los_part_ioctl	(	INT32	pt,
		INT32	cmd,
		VOID *	buf
	)

Get information of chosen partition.

Description:

By passed command to get information of chosen partition.

注意

参数

pt	[IN] Type INT32 partition number,less than the value defined by SYS_MAX_PART.
cmd	[IN] Type INT32 command to issu, currently support GET_SECTOR_COUNT, GET_SECTOR_SIZE, GET_BLOCK_SIZE, CTRL_SYNC.
buf	[OUT] Type #VOID * memory to store the information, the size must enough for data type (UINT64) when cmd type is DISK_GET_SECTOR_COUNT, others is size_t.

返回值

#0	Get information success.
#-1	Get information failed.

Dependency:

• disk.h

参见

None

在文件 disk.c 第 1193 行定义.

{
    struct geometry info;
    los_part *part = get_part(pt);
    los_disk *disk = NULL;
 
    if (part == NULL) {
        return VFS_ERROR;
    }
 
    disk = get_disk((INT32)part->disk_id);
    if (disk == NULL) {
        return VFS_ERROR;
    }
 
    DISK_LOCK(&disk->disk_mutex);
    if ((part->dev == NULL) || (disk->disk_status != STAT_INUSED)) {
        goto ERROR_HANDLE;
    }
 
    if (cmd == DISK_CTRL_SYNC) {
        DISK_UNLOCK(&disk->disk_mutex);
        return ENOERR;
    }
 
    if (buf == NULL) {
        goto ERROR_HANDLE;
    }
 
    (VOID)memset_s(&info, sizeof(info), 0, sizeof(info));
 
    struct block_operations *bops = (struct block_operations *)((struct drv_data *)part->dev->data)->ops;
    if ((bops == NULL) || (bops->geometry == NULL) ||
        (bops->geometry(part->dev, &info) != 0)) {
        goto ERROR_HANDLE;
    }
 
    if (cmd == DISK_GET_SECTOR_COUNT) {
        *(UINT64 *)buf = part->sector_count;
        if (*(UINT64 *)buf == 0) {
            goto ERROR_HANDLE;
        }
    } else if (cmd == DISK_GET_SECTOR_SIZE) {
        *(size_t *)buf = info.geo_sectorsize;
    } else if (cmd == DISK_GET_BLOCK_SIZE) { /* Get erase block size in unit of sectors (UINT32) */
        if ((bops->ioctl == NULL) ||
            (bops->ioctl(part->dev, GET_ERASE_BLOCK_SIZE, (UINTPTR)buf) != 0)) {
            goto ERROR_HANDLE;
        }
    } else {
        goto ERROR_HANDLE;
    }
 
    DISK_UNLOCK(&disk->disk_mutex);
    return ENOERR;
 
ERROR_HANDLE:
    DISK_UNLOCK(&disk->disk_mutex);
    return VFS_ERROR;
}

函数调用图:

los_part_read()

INT32 los_part_read	(	INT32	pt,
		VOID *	buf,
		UINT64	sector,
		UINT32	count,
		BOOL	useRead
	)

Read data from chosen partition.

Description:

Read data from chosen partition.

注意

• The sector size of the disk to be read should be acquired by los_part_ioctl before calling this function.
• The parameter buf must point to valid memory and the buf size is count * sector_size.

参数

pt	[IN] Type INT32 partition number, less than the value defined by SYS_MAX_PART.
buf	[OUT] Type #VOID * memory which used to store the data to be read.
sector	[IN] Type UINT64 start sector number of chosen partition.
count	[IN] Type UINT32 the expected sector count for reading.
useRead	[IN] Type BOOL FALSE when reading large contiguous data, TRUE for other situations

返回值

#0	Read success.
#-1	Read failed.

Dependency:

• disk.h

参见

los_part_read

Read data from chosen partition.

在文件 disk.c 第 1080 行定义.

{
    const los_part *part = get_part(pt);//先拿到分区信息
    los_disk *disk = NULL;
    INT32 ret;
 
    if (part == NULL) {
        return VFS_ERROR;
    }
 
    disk = get_disk((INT32)part->disk_id);//再拿到磁盘信息
    if (disk == NULL) {
        return VFS_ERROR;
    }
 
    DISK_LOCK(&disk->disk_mutex);//锁磁盘
    if ((part->dev == NULL) || (disk->disk_status != STAT_INUSED)) {
        goto ERROR_HANDLE;
    }
 
    if (count > part->sector_count) {//不能超过分区总扇区数量
        PRINT_ERR("los_part_read failed, invalid count, count = %u\n", count);
        goto ERROR_HANDLE;
    }
 
    /* Read from absolute sector. */
    if (part->type == EMMC) {//如果分区类型是磁盘介质
        if ((disk->sector_count - part->sector_start) > sector) {//从绝对扇区读取
            sector += part->sector_start;
        } else {
            PRINT_ERR("los_part_read failed, invalid sector, sector = %llu\n", sector);
            goto ERROR_HANDLE;
        }
    }
 
    if ((sector >= GetFirstPartStart(part)) &&  //扇区范围判断
        (((sector + count) > (part->sector_start + part->sector_count)) || (sector < part->sector_start))) {
        PRINT_ERR("los_part_read error, sector = %llu, count = %u, part->sector_start = %llu, "
                  "part->sector_count = %llu\n", sector, count, part->sector_start, part->sector_count);
        goto ERROR_HANDLE;
    }
    //读取大量连续数据时，useRead 应为 FALSE
    /* useRead should be FALSE when reading large contiguous data */
    ret = los_disk_read((INT32)part->disk_id, buf, sector, count, useRead);
    if (ret < 0) {
        goto ERROR_HANDLE;
    }
 
    DISK_UNLOCK(&disk->disk_mutex);
    return ENOERR;
 
ERROR_HANDLE:
    DISK_UNLOCK(&disk->disk_mutex);
    return VFS_ERROR;
}

函数调用图:

los_part_write()

INT32 los_part_write	(	INT32	pt,
		const VOID *	buf,
		UINT64	sector,
		UINT32	count
	)

Write data to chosen partition.

Description:

Write data to chosen partition.

注意

• The sector size of the disk to be write should be acquired by los_part_ioctl before calling this function.
• The parameter buf must point to valid memory and the buf size is count * sector_size.

参数

pt	[IN] Type INT32 partition number,less than the value defined by SYS_MAX_PART.
buf	[IN] Type #VOID * memory which used to storage the written data.
sector	[IN] Type UINT64 start sector number of chosen partition.
count	[IN] Type UINT32 the expected sector count for write.

返回值

#0	Write success.
#-1	Write failed.

Dependency:

• disk.h

参见

los_part_read

Write data to chosen partition.

在文件 disk.c 第 1136 行定义.

{
    const los_part *part = get_part(pt);
    los_disk *disk = NULL;
    INT32 ret;
 
    if (part == NULL) {
        return VFS_ERROR;
    }
 
    disk = get_disk((INT32)part->disk_id);
    if (disk == NULL) {
        return VFS_ERROR;
    }
 
    DISK_LOCK(&disk->disk_mutex);
    if ((part->dev == NULL) || (disk->disk_status != STAT_INUSED)) {
        goto ERROR_HANDLE;
    }
 
    if (count > part->sector_count) {
        PRINT_ERR("los_part_write failed, invalid count, count = %u\n", count);
        goto ERROR_HANDLE;
    }
 
    /* Write to absolute sector. */
    if (part->type == EMMC) {
        if ((disk->sector_count - part->sector_start) > sector) {
            sector += part->sector_start;
        } else {
            PRINT_ERR("los_part_write failed, invalid sector, sector = %llu\n", sector);
            goto ERROR_HANDLE;
        }
    }
 
    if ((sector >= GetFirstPartStart(part)) &&
        (((sector + count) > (part->sector_start + part->sector_count)) || (sector < part->sector_start))) {
        PRINT_ERR("los_part_write, sector = %llu, count = %u, part->sector_start = %llu, "
                  "part->sector_count = %llu\n", sector, count, part->sector_start, part->sector_count);
        goto ERROR_HANDLE;
    }
    //sector已变成磁盘绝对扇区
    ret = los_disk_write((INT32)part->disk_id, buf, sector, count);//直接写入磁盘,
    if (ret < 0) {
        goto ERROR_HANDLE;
    }
 
    DISK_UNLOCK(&disk->disk_mutex);
    return ENOERR;
 
ERROR_HANDLE:
    DISK_UNLOCK(&disk->disk_mutex);
    return VFS_ERROR;
}

函数调用图:

OsClearUsbStatus()

VOID OsClearUsbStatus

(

UINT32

diskId

)

Set usb mode.

Description:

Clear the corresponding bit of g_usbMode as usb host mode.

注意

• diskId should be [0,SYS_MAX_DISK)

参数

diskId

[IN] Type # unsigned int disk id.

Dependency:

• driver.h

参见

OsSetUsbStatus

在文件 disk.c 第 249 行定义.

{
    if (diskID < SYS_MAX_DISK) {
        g_usbMode &= ~((1u << diskID) & UINT_MAX);
    }
}

OsSetUsbStatus()

VOID OsSetUsbStatus

(

UINT32

diskId

)

Set usb mode.

Description:

Set the corresponding bit of g_usbMode as usb host mode.

注意

• diskId should be [0,SYS_MAX_DISK)

参数

diskId

[IN] Type # unsigned int disk id.

Dependency:

• driver.h

参见

OsClearUsbStatus

在文件 disk.c 第 242 行定义.

{
    if (diskID < SYS_MAX_DISK) {
        g_usbMode |= (1u << diskID) & UINT_MAX;
    }
}

show_part()

VOID show_part

(

los_part *

part

)

Print partition information.

Description:

Print partition information.

注意

参数

part	[IN] Type los_part * partition control structure pointer

Dependency:

• disk.h

参见

None

Print partition information.

在文件 disk.c 第 1810 行定义.

{
    if ((part == NULL) || (part->dev == NULL)) {
        PRINT_ERR("part is NULL\n");
        return;
    }
 
    PRINTK("\npart info :\n");
    PRINTK("disk id          : %u\n", part->disk_id);   //磁盘ID
    PRINTK("part_id in system: %u\n", part->part_id);   //在整个系统的分区ID
    PRINTK("part no in disk  : %u\n", part->part_no_disk);//在磁盘分区的ID
    PRINTK("part no in mbr   : %u\n", part->part_no_mbr);//主分区ID
    PRINTK("part filesystem  : %02X\n", part->filesystem_type);//文件系统(FAT | NTFS)
    PRINTK("part sec start   : %llu\n", part->sector_start);//开始扇区
    PRINTK("part sec count   : %llu\n", part->sector_count);//扇区大小
}

这是这个函数的调用关系图: