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   xfs_io    ( 8 )

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FILESYSTEM COMMANDS

bulkstat [ -a agno ] [ -d ] [ -e endino ] [ -n batchsize ] [ -s startino ] [ -v version"] Display raw stat information about a bunch of inodes in an XFS filesystem. Options are as follows: -a agno Display only results from the given allocation group. If not specified, all results returned will be displayed. -d Print debugging information about call results. -e endino Stop displaying records when this inode number is reached. Defaults to stopping when the system call stops returning results. -n batchsize Retrieve at most this many records per call. Defaults to 4,096. -s startino Display inode allocation records starting with this inode. Defaults to the first inode in the filesystem. If the given inode is not allocated, results will begin with the next allocated inode in the filesystem. -v version Use a particular version of the kernel interface. Currently supported versions are 1 and 5.

bulkstat_single [ -d ] [ -v version ] [ inum... | special... ] Display raw stat information about individual inodes in an XFS filesystem. The -d and -v options are the same as the bulkstat command. Arguments must be inode numbers or any of the special values: root Display information about the root directory inode.

freeze Suspend all write I/O requests to the filesystem of the current file. Only available in expert mode and requires privileges.

thaw Undo the effects of a filesystem freeze operation. Only available in expert mode and requires privileges.

inject [ tag ] Inject errors into a filesystem to observe filesystem behavior at specific points under adverse conditions. Without the tag argument, displays the list of error tags available. Only available in expert mode and requires privileges.

resblks [ blocks ] Get and/or set count of reserved filesystem blocks using the XFS_IOC_GET_RESBLKS or XFS_IOC_SET_RESBLKS system calls. Note -- this can be useful for exercising out of space behavior. Only available in expert mode and requires privileges.

shutdown [ -f ] Force the filesystem to shut down, preventing any further IO. XFS and other filesystems implement this functionality, although implementation details may differ slightly. Only available in expert mode and requires privileges.

By default, the filesystem will not attempt to flush completed transactions to disk before shutting down the filesystem. This simulates a disk failure or crash. -f Force the filesystem to flush all completed transactions to disk before shutting down, matching XFS behavior when critical corruption is encountered.

statfs [ -c ] [ -g ] [ -s ] Report selected statistics on the filesystem where the current file resides. The default behavior is to enable all three reporting options: -c Display XFS_IOC_FSCOUNTERS summary counter data. -g Display XFS_IOC_FSGEOMETRY filesystem geometry data. -s Display statfs(2) data.

inode [ [ -n ] number ] [ -v ] The inode command queries physical information about an inode. With no arguments, it will return 1 or 0, indicating whether or not any inode numbers greater than 32 bits are currently in use in the filesystem. If given an inode number as an argument, the command will return the same inode number if it is in use, or 0 if not. With -n number , the next used inode number after this number will be returned, or zero if the supplied inode number is the highest one in use. With -v the command will also report the number of bits (32 or 64) used by the inode number printed in the result; if no inode number was specified on the command line, the maximum possible inode number in the system will be printed along with its size.

inumbers [ -a agno ] [ -d ] [ -e endino ] [ -n batchsize ] [ -s startino ] [ -v version ] Prints allocation information about groups of inodes in an XFS filesystem. Callers can use this information to figure out which inodes are allocated. Options are as follows: -a agno Display only results from the given allocation group. If not specified, all results returned will be displayed. -d Print debugging information about call results. -e endino Stop displaying records when this inode number is reached. Defaults to stopping when the system call stops returning results. -n batchsize Retrieve at most this many records per call. Defaults to 4,096. -s startino Display inode allocation records starting with this inode. Defaults to the first inode in the filesystem. If the given inode is not allocated, results will begin with the next allocated inode in the filesystem. -v version Use a particular version of the kernel interface. Currently supported versions are 1 and 5.

scrub type [ agnumber | ino gen ] Scrub internal XFS filesystem metadata. The type parameter specifies which type of metadata to scrub. For AG metadata, one AG number must be specified. For file metadata, the scrub is applied to the open file unless the inode number and generation number are specified.

repair type [ agnumber | ino gen ] Repair internal XFS filesystem metadata. The type parameter specifies which type of metadata to repair. For AG metadata, one AG number must be specified. For file metadata, the repair is applied to the open file unless the inode number and generation number are specified.

label [ -c | -s label ] On filesystems that support online label manipulation, get, set, or clear the filesystem label. With no options, print the current filesystem label. The -c option clears the filesystem label by setting it to the null string. The -s label option sets the filesystem label to label. If the label is longer than the filesystem will accept, xfs_io will print an error message. XFS filesystem labels can be at most 12 characters long.

fsmap [ -d | -l | -r ] [ -m | -v ] [ -n nx ] [ start ] [ end ] Prints the mapping of disk blocks used by the filesystem hosting the current file. The map lists each extent used by files, allocation group metadata, journalling logs, and static filesystem metadata, as well as any regions that are unused. Each line of the listings takes the following form:

extent: major:minor [startblock..endblock]: owner startoffset..endoffset length

Static filesystem metadata, allocation group metadata, btrees, journalling logs, and free space are marked by replacing the startoffset..endoffset with the appropriate marker. All blocks, offsets, and lengths are specified in units of 512-byte blocks, no matter what the filesystem's block size is. The optional start and end arguments can be used to constrain the output to a particular range of disk blocks. If these two options are specified, exactly one of -d, -l, or -r must also be set. -d Display only extents from the data device. This option only applies for XFS filesystems. -l Display only extents from the external log device. This option only applies to XFS filesystems. -r Display only extents from the realtime device. This option only applies to XFS filesystems. -m Display results in a machine readable format (CSV). This option is not compatible with the -v flag. The columns of the output are: extent number, device major, device minor, physical start, physical end, owner, offset start, offset end, length. The start, end, and length numbers are provided in units of 512b. The owner field is a special string that takes the form:

inode_%lld_data for inode data. inode_%lld_data_bmbt for inode data extent maps. inode_%lld_attr for inode extended attribute data. inode_%lld_attr_bmbt for inode extended attribute extent maps. special_%u:%u for other filesystem metadata.

-n num_extents If this option is given, fsmap obtains the extent list of the file in groups of num_extents extents. In the absence of -n, fsmap queries the system for extents in groups of 131,072 records.

-v Shows verbose information. When this flag is specified, additional AG specific information is appended to each line in the following form:

agno (startagblock..endagblock) nblocks flags

A second -v option will print out the flags legend. This option is not compatible with the -m flag.