inode_vxfs(F)

Synopsis

#include <sys/types.h> 
#include <sys/fs/vx_inode.h> 

Description

An inode entry has the following format:

i_mode

The mode and type of file.

i_nlink

The number of links to the file.

i_uid

The inode owner.

i_gid

The inode group.

i_size

The size in bytes of the file. Eight bytes have been allocated. Only four bytes are used in the current implementation.

i_atime

Time of last access, in timestruc_t format.

i_mtime

Time of last modification, in timestruc_t format.

i_ctime

Time of last inode change, in timestruc_t format.

i_aflags

These flags are used to control the allocation and extension of files.

VX_AF_IBAD

If this flag is set, the inode is invalid in some way. It should be cleared when fsck is run (see fsck_vxfs(ADM)).

VX_AF_NOEXTEND

If this flag is set, the file may not be extended once the current reservation is exceeded. The reservation may be increased by the VX_SETEXT ioctl, but the file will not be automatically extended.

VX_AF_NOGROW

If this flag is set, the file may not be extended once the current reservation is exceeded. It should be cleared on truncation or when setext(C) is run. This flag is usually set because an I/O error occurs while extending a file.

VX_AF_ALIGN

If this flag is set, the file must be allocated in extents of a fixed size and alignment. If an extent of i_fixextsize blocks aligned on an i_fixextsize boundary can't be found, then the allocation will fail. The alignment is relative to the beginning of the allocation unit.

i_orgtype

Mapping type. Indicates how the inode mapping area is to be interpreted. Currently there are two mapping types supported:

IORG_NONE

Mapping area is unused. IORG_NONE is used for files that have no associated data storage. Since there is no need for either extents or immediate data, the mapping area is unused. Block and character special files are an example of files that use the IORG_NONE organization type.

IORG_EXT4

Mapping area consists of an array of 32-bit extent block addresses and sizes.

IORG_IMMED

Mapping area itself is a data block. This mapping is referred to as Immediate Inode Data.

IORG_TYPED

Mapping area consists of type-extent structures.

i_eopflags

Extended inode operation flag area.

i_eopdata

Extended inode operation data area.

i_ftarea

This is a union. The contents are determined by file type.

For devices, the following field is supported:

i_rdev

The device number of a block or character special device.

For directories, the following field is supported:

i_dotdot

The parent directory inode inumber if the inode is a directory. This replaces the standard ``..'' entry in the first directory block. The vxfs file system does not have explicit ``.'' and ``..'' entries.

For regular files, the following fields are supported:

i_reserve

The number of data blocks reserved for exclusive use by the file (preallocation). A preallocation may be requested using ioctl. See vxfsio(HW).

i_fixextsize

Set when the inode has a fixed extent size. The default is to have a variable extent size allocation policy. A fixed extent size may be specified using ioctl. See vxfsio(HW).

For structural files, the following fields are supported:

i_matchino

(Version 2 layout and later only.) The inode number of the ``matching'' inode. For replicated files, this is the inode of the replica. For extent map reorganization files, this is the inode of the file being reorganized.

i_fsetindex

(Version 2 layout and later only.) The index of the fileset associated with this inode.

i_blocks

The number of blocks currently allocated to the file, including any blocks allocated for indirect address extents.

i_gen

The generation number. A serial number which is incremented whenever the inode is freed and reallocated. It is designed to provide a ``handle'' for stateless servers such as NFS.

i_vversion

A count of the number of times the inode metadata has been modified. This field is a 64-bit number.

ic_org

The mapping area. This field is a union based on the value of i_orgtype and the file system type.

For the vxfs IORG_IMMED organization type, the following structure is used:

i_immed

The immediate inode data area, NIMMED_N (currently 96) bytes in length (see fs_immedlen). Any directory or symbolic link which is <= 96 bytes in length will be stored directly in the inode.

For the vxfs IORG_EXT4 organization type, the following structure is used:

i_spare

Four bytes of padding, not used.

i_ies

Indirect extent size. This is the size in blocks of the indirect data extents in the file.

i_ie

Array of indirect address extents. There are NIADDR indirect address extents. The indirect address extents are 8192 bytes long. Each indirect address extent may contain up to 2048 extent addresses.

The first indirect address extent is used for single indirection. With single indirection, each entry in the indirect address extent indicates the starting block number of a data extent.

The second indirect address extent is a double indirect address extent. With double indirection, each entry in the indirect address extent indicates the starting block number of a single indirect address extent.

i_dext

An array of structures containing the direct extent addresses and sizes. Up to NDADDR_N direct extents are supported. Since a variable length extent allocation policy is used, each direct extent may have a different size. Each structure contains the following elements:

i_de Direct extent address.

i_des Direct extent size.

reserved

(Version 1 layout only.) Bytes 176 to the end of the inode are empty and reserved.

i_iattrino

(Version 2 layout and later only.) Indirect attribute inode. This identifies the inode in the attribute fileset that contains indirect attribute references.

The remaining bytes of the inode are reserved for extended attribute records, which are formatted as follows:

length

The exact length of the attribute record. If this is not a multiple of 4 bytes, the start of the next attribute record is found by rounding the length up to a 4 byte boundary.

format

The format of the data layout of the remainder of the attribute record. Each attribute consists of a class identifying the attribute's administrative domain; a subclass identifying the attribute within the administrative domain; and data. The valid record formats are:

ATTR_EXTIMMED

This record extends the immediate data area so that files larger than 96 bytes can be stored directly in the inode.

ATTR_IMMED

The attribute is stored directly in the inode. The fields in the rest of this record are:

class

The class of the attribute.

subclass

The subclass of the attribute.

data

The attribute data.

ATTR_DIRECT

When attributes are too large to store directly in the inode, each attribute is stored in its own file. This record lists each attribute along with the inode number corresponding to the file in which the attribute is stored. The number of entries in the list is determined by the length of the record. The fields in each entry are:

class

The class of the attribute.

subclass

The subclass of the attribute.

length

The length of the attribute data. This allows attribute operations to check the length of an attribute without reading the attribute inode.

inumber

The inode number of the file containing the attribute data. The inode is part of the attribute fileset.

References