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: AM:155

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. 3. 13 19FAT32.. 32NTFS 41UFS.. 47FFS.. 63VFS.. 69ext2, ext3, ext4.. 74HFS. 77Yaffs 85 90

(1)

(Operating System) .

(interface) . .

(2) (resource allocation). .

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(3)

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(2)

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Windows (98, NT, 2000, XP, Vista, 7, Server)FreeBSDLinux Distributions (Ubuntu, Fedora, Mandriva)Macintosh OS v 10.x (Leopard, Tiger)AndroidWindows Mobile CEHaikuSolarisIPhone OSCentOSOpenBSDUnix

. , , , , .

, .

/ . (1)

, , .

, , I-nodes, soft links, hard links. (2)

FAT (FAT12, FAT16, FAT32, exFAT)NTFSHFS HFS+HPFSUFS ext2, ext3, ext4 btrfsISO 9660ODS-5Veritas File SystemZFSUDF .

Pipes I nodes (Unix)

(Files)

, (attributes - properties). . , :

- (1)

(read only)

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(2)

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, . : , , ( ). , . (1)

. , .

. , ' .

. . . (2)

(3)

, . . , . (.. ), .

. .. , . , , . .

(Directories)

(Directories): file system. .

/ Directories(1)

/ Create: directory.

/ Delete: directory. directory .

/ Open: directory . open.

/ Close: .

/ Rename:

/ Directories(2)

Link: linking directories. directory . directories.

Unlink: link directory. unlink directory file system.

/ .

(1)

.

#x, , * .

,

.

(2)

(1)

,

.

.

.

(2)

(1)

.

.

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.

(2)

(1)

(2)

boot block superblock filesystem, blocks ... bitmap blocks. i-nodes, , . root directory file system tree .

FAT32 (File Allocation Table)

FAT32: File Allocation Table 32

Windows 95OSR2, FAT 32 bit 16 bit .

2 GB.FAT32 (1)

FAT32 65536 clusters clusters . cluster 512 Bytes volume 2 TB, cluster 4096 Bytes 16TB.

32 bit 28 FAT cluster, 4 .

FAT32 (2)

sector Master Boot Record (MBR). sector 512 Bytes , 512 Bytes sector 446 Bytes . 64 Bytes 4 16 Bytes. Partition Table. Bytes 0x55, 0xAA bytes MBR , . 4, .FAT32 1

FAT32 2

(partition) 16 bytes 5 byte, Type Code, , bytes 9 12 .

FAT32 Type Code 0x0B 0x0C.

sectors .

FAT32 3

FAT32 sector Volume ID.

LBA .

FAT (12, 16)

sector .

FAT32 4

FAT32 5

FieldMicrosoft's NameOffsetSizeValueBytes Per SectorBPB_BytsPerSec0x0B16 BitsAlways 512 BytesSectors Per ClusterBPB_SecPerClus0x0D8 Bits1,2,4,8,16,32,64,128Number of Reserved SectorsBPB_RsvdSecCnt0x0E16 BitsUsually 0x20Number of FATsBPB_NumFATs0x108 BitsAlways 2Sectors Per FATBPB_FATSz320x2432 BitsDepends on disk sizeRoot Directory First ClusterBPB_RootClus0x2C32 BitsUsually 0x00000002Signature(none)0x1FE16 BitsAlways 0xAA55

FAT32 . sector Volume ID, sectors. sectors (2) File Allocation Table (FAT), clusters .

FAT32 6

NTFS (New Technology File System)

NTFS: New Technology File System, 32 Bit . FAT , . , . Microsoft , .

NTFS (1)

Windows NT (NT, XP, Vista, 7, Server Editions) . Windows , .

NTFS (2)

:

NTFS .

.

cluster .

NTFS (1)

NTFS

RAID Volumes . rebuild .

UNICODE .

4 GB NTFS , flash drives 4 GB NTFS 4 GB.NTFS (2)

NTFS

, .

Server Active Directory (domain), .

(user quotas) .NTFS (3)

Unix File System (UFS)

Layers Unix

access

through

user mode

access through

kernel mode

Users

Shells

UNIX operating system (kernel)

Hardware

Unix

Computer hardware

The shell and other basic time-sharing utilities

The UNIX system kernel

Compilers

Spreadsheet calculators

Mail and message facilities

Editors

Interpreters

Database management systems

Word processors

Calendar systems

Inventory control systems

Formatters

Unix

Application

Users

Interface

(AUI)

Application

Programmers

Interface

(API)

Operating

System

Applications: Compilers, word processors, spreadsheets, ftp, telnet, Web browser, etc.

UNIX shell

Language libraries: C, C++, Java, Fortran, etc.

System call interface (entry points to kernel)

UNIX kernel:

File management

Interprocess communication (IPC)

Process management

CPU

scheduler

Primary and secondary storage management

Device drivers: Mouse driver, printer driver, CD-ROM driver, hard disk driver, etc.

Hardware: Wires, capacitors, resistors, transistors, Ics, mouse, display monitor, keyboard, CPU, RAM, hard disk, CD-ROM, printer, etc.

. : (source & ) :, ,

: , . .

:

char/block special:

Pipe : , .

Passwd Motd " "Mtab Utmp Termcap

/etc

consol UNIXnull E Lp mt# tty#

/dev

(directory, ) : . directory directories . "", "" "" , "" . - Directories

Unix (1)

i-node, . i-node 15 . 12 . , index, . , .

Unix (2)

I nodes (1)

H I node :

Field

Example

Owner of the file

fred

Group Id (group to which owner belongs)

staff

File Type

regular

Permissions (see notes below)

rwxr-xr-x

Last accessed

10 Dec 1991 12:00

Last Modified

21 Nov 1991 17:45

Last Inode Modification

21 Nov 1991 17:45

File size

10300 bytes

Number of links

3

Pointers to disk allocations

See below

I nodes (2)

Type: e.g., normal, directory, special

User-id and group-id of owner

Access permissions

Time of creation, last update and last access

Reference count (number of links to this inode)

Direct blocks

Indirect blocks

Double-indirect blocks

Triple-indirect blocks

Indirect blocks

File contents

Direct blocks

Direct blocks

I nodes (3)

INODE POINTERS

DATA

BLOCKS

INDEX BLOCKS

Direct 0

Direct 1

Direct 2

Direct 9

Single Indirect

Double Indirect

Triple Indirect

Volume (1) *Boot Block. .Super Block. .

Boot Block

Inode Block

Super Block

Data Blocks

Volume (2) *

I-node Block. i-node (information node) Data Block. Data Blocks. . , .

Inodes Files

Owner Group Type Permisn Time Address

Unix

read(3, &buffer, 1024)

User space

Boot block

Disk

Inode table Data blocks

Super-block Super-block

Top of free inode list

Top of free block list

Per-process

open file table

0

1 Kernel

2

3

In-memory copy

of super-block System open file table Active inode table

offset=1234

Metadata

Fast file system (ffs)

FFS(1)

FreeBSD Fast File System FFS, Unix, UFS. FreeBSD, .

FreeBSD , , .. USB , flash, . , - , Extended File System (EXT) LinuxR Z File System (ZFS) Sun.

FFS(2)

T (cylinder groups) .

i-nodes data blocks.

, i-nodes data blocks. .

blocks, superblocks : , , , (free list), . data blocks .

FFS(3)

data block (. data block data blocks - fragments).

data blocks , "" data blocks fragments frags.

data blocks , fragments .

fragment data block 1/8 . .

FFS(4)

T data blocks fragments data blocks / fragments .

,

(. data block 8 KBytes - fragment 1 KByte) .

FFS(5)

FFS (fast filesystem) FreeBSD single C ( 8-bit clean), . , 8-bit .

, FFS wide multibyte. patches FFS .

Linux VFS (Virtual File System)

Linux VFS

Linux ( mount) .

To Linux 4 slide.Page cachei-node cacheBuffer cacheDirectory cache

VFS (layer) I/O . (abstraction layer).

Linux VFS Context

(1)

VFSInode CacheDirectory CacheNTFSExt2CryptFSBuffer CacheDisk DriversUser space

(2)

ext2, ext3, ext4 (Extended File System)

Ext4 (1)

ext2, ext3, ext4: GNU/Linux Ubuntu ext4 .

Ext4 ( Extended File System) Ext3 .

ext4, ext3, , .

Ext4 (2)

64-bit .

Ext3 Ext2 .

Persistent Pre allocation.

Delayed allocation.

.

Hierarchical File System (HFS / HFS+)

HFS (1)

HFS Apple 1985, Apple Macintosh, Macintosh(MFS)

To HFS (Catalog File) (B trees) .

512 bytes.

HFS + HFS Plus Apple Inc HFS ( File System) , Mac OS.

HFS (1)

Sector: read/write driver . ( 512Bytes)

allocation block: allocate filesystem ( 4KB). allocation block allocation number .

Clumps: groups allocation blocks. allocation block clump fragmation.

Extent: allocation blocks fork(data resource). . allocation number block allocation blocks.

HFS (2)

Special files: filesystem folders, user files, attributes. files:

Catalog file (B-Tree): . catalog information files, folders. catalog file b-tree.

Attributes file (B-Tree): .

Extents overflow file (B-Tree): extents 8 catalog file.

HFS (3)

Allocation file (bitmap): allocation block used or free.

Startup file: MAC OS. Volume Header.

B-Trees: B-Trees catalog, extents overflow attributes. B+-Trees . data fork . B-tree nodes, records, data. B-Tree . .

HFS (1)

HFS :

0 1 , .

2 Master Directory Block (MDB). , , , , Bitmap .

HFS (2)

3 Volume Bitmap, .

MDB Alternate Master Directory Block (Alternate MDB) . Extents .

Extent Overflow File - , extents .

HFS (3)

(Catalog File) - . . File Thread Record File Record Directory Thread Record Directory Record. (CNID Catalog Node ID).

Yaffs (Yet Another File System)

YAFFS (1)

YAFFS NAND , Android (smart phones) .

Linux, ucLinux, Windows CE.

JFFSv1 JFFSv2 NAND .

YAFFS

(easily ported)

log (log structured file systems) (wear leveling techniques). NAND.

(fast mount).

RAM .

YAFFS

YAFFS1, YAFFS2

, .

512 bytes. 1 0 byte, .H 2KB, . / . RAM, 50%. MLC NAND TOSHIBA SANDISK.

(1)

http://en.wikipedia.org/wiki/NTFS

http://en.wikipedia.org/wiki/File_Allocation_Table

http://en.wikipedia.org/wiki/Hierarchical_File_System

http://www.cslab.ntua.gr/courses/os/files/2011-12/os-07-filesystems.pdf

http://docs.fedoraproject.org/el-GR/Fedora/9/html/Release_Notes/sn-FileSystems.html

http://en.wikipedia.org/wiki/Unix_File_System

http://static.usenix.org/event/usenix01/full_papers/kroeger/kroeger_html/node8.html

(2)

http://www.geeksforgeeks.org/archives/20091

http://igm.univ-mlv.fr/~dr/XPOSE/NTFSvsUFS/right.htm

http://www.yaffs.net/

http://en.wikipedia.org/wiki/YAFFS

http://wookware.org/talks/yaffscelf2007.pdf

www.google.com

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