Linux的文件夹需要包含"."和".."才会被视为一个有效的目录
通过在新建的文件夹中创建"."和".."目录项修复这个BUG

Close #I3XMY6
Signed-off-by: NFar <yesiyuan2@huawei.com>

Signed-off-by: Njianjian <xingjian_liu@yeah.net>

1.remove redundant headfile in kernel, such as:
  compiler.h;debug.h;automount.h;inode.h;syslog.h;net.h;
2.split fs.h to file.h and driver.h
3.move vnode.h and path_cache.h to vfs/include
4.remove redundant interface and defines

close: #I3RTNR
Signed-off-by: Nmucor <mucorwang@gmail.com>

在init_cluster函数中，若未打开LOSCFG_FS_FAT_VIRTUAL_PARTITION会导致循环初始化
簇时，未调用sync_window函数，进而导致创建的文件夹未能正确置零。

Close #I3W1IW
Signed-off-by: NFar <yesiyuan2@huawei.com>

1 将fatfs_creat与fatfs_mkdir抽象成fatfs_creat_obj，通过参数type控制创建的对象类型；
2 新增fatfs_symlink与fatfs_readlink接口，其中：
   1) fatfs_symlink通过fatfs_creat_obj创建出符号链接文件，并为其申请新簇，将target内容写入簇的第一个sector；
   2) fatfs_readlink读出符号链接文件对应簇中第一个sector的内容

close #I3V8D1
Signed-off-by: Nchenjing <chenjing139@huawei.com>
Change-Id: I38dfaa28af156399817530923534d5b73b4c64af

1，VFS代码中不修改参数增加const修饰
2，fs_file_mapping.c: 增加安全函数的判空
3，path_cache.c: sizeof改为使用类型
4，fs_syscall.c: 对NULL解引用
5，VnodeLookup：冗余的判空，及不正确的判空

close: I3UMWD
Signed-off-by: yansira <yansira@hotmail.com>

fix typos length、there、necessary

close https://gitee.com/openharmony/kernel_liteos_a/issues/I3RSY0

FAT12/FAT16 partition has no FSINFO sector storing the free cluster number,
so scanning the FAT is necessary to get the free clusters nums.

Close #I3Q0VS

if fatfs_mkfs returns a error, format may return without drop the vnode mutex, which may cause deadlock

Close #I3OFAY

The errno of unrecognized fat filesystem changes from ENOENT to ENOTSUP.

Close #I3O8IF

When fatfs_lookup find a vnode from hashlist, the field parent of vnode should be updated,
because the old parent may be reclaimed.

Close #I3NNFA

Bug: #I3NEVN
Test:

Change-Id: I052d930d54e63179b17b77f02c107a015f3cfc3f

Bug: #I3J1IC
Test: io test 1000 time

1. Bcache block with high mem address is after lower mem address in RCU list when initing bcache.
2. Format will clear the bcache before writing the FAT.
3. The fatfs_readdir use the bcache writing block to reduce the chance of data switching out
4. Add performance analysing macron switch

Change-Id: I8fbc48418509d2e660d725d2c265266e931c26f8

Change-Id: Ic443742e125915f0e5332a338dedea5c40348928

Change-Id: I9c49073ad2bbd668102d20da8ff7a8d680890deb

Feature or Bugfix:Feature
Binary Source:Huawei
PrivateCode(Yes/No):Yes

Change-Id: I175d2648bc6f9078c34de2c0a5c93fda10b86c47
ChangeID:13306388

Change-Id: Ia6c1f6302407a707b3ec9b805f4c92d8a7970b86