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IOCT-XF-RTGROU-GEOMETRY

Section: System Calls (2)
Updated: 202-0-18
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NAME

ioctl_xfs_rtgroup_geometry - query XFS realtime group geometry information

SYNOPSIS

#include <xfs/xfs_fs.h>

int ioctl(int fd, XFS_IOC_RTGROUP_GEOMETRY, struct xfs_rtgroup_geometry *arg);

DESCRIPTION

This XFS ioctl retrieves the geometry information for a given realtime group. The geometry information is conveyed in a structure of the following form:

struct xfs_rtgroup_geometry {
        __u32  rg_number;
        __u32  rg_length;
        __u32  rg_sick;
        __u32  rg_checked;
        __u32  rg_flags;
        __u32  rg_reserved[27];
};

rg_number: The caller must set this field to the index of the realtime group that the caller wishes to learn about.
rg_length: The length of the realtime group is returned in this field, in units of filesystem blocks. rg_flags The caller can set this field to change the operational behavior of the ioctl. Currently no flags are defined, so this field must be zero.
rg_reserved and rg_pad: All reserved fields will be set to zero on return.

The fields rg_sick and rg_checked indicate the relative health of various realtime group metadata:

[bu]: If a given sick flag is set in rg_sick, then that piece of metadata has been observed to be damaged. The same bit will be set in rg_checked.
[bu]: If a given sick flag is set in rg_checked and is not set in rg_sick, then that piece of metadata has been checked and is not faulty.
[bu]: If a given sick flag is not set in rg_checked, then no conclusion can be made.

The following flags apply to these fields:

XFS_RTGROUP_GEOM_SICK_SUPER: Realtime group superblock.
XFS_RTGROUP_GEOM_SICK_BITMAP: Realtime bitmap for this group.
XFS_RTGROUP_GEOM_SICK_SUMMARY: Realtime summary for this group.
XFS_RTGROUP_GEOM_SICK_RTRMAPBT: Reverse mapping btree for this group.

RETURN VALUE

On error, -1 is returned, and errno is set to indicate the error.

ERRORS

Error codes can be one of, but are not limited to, the following:

EFSBADCRC: Metadata checksum validation failed while performing the query.
EFSCORRUPTED: Metadata corruption was encountered while performing the query.
EINVAL: The specified realtime group number is not valid for this filesystem.
EIO: An I/O error was encountered while performing the query.

CONFORMING TO

This API is specific to XFS filesystem on the Linux kernel.