ioctl_xfs_fsinumbers(2) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | SEE ALSO | COLOPHON

IOCTL-XFS-FSINUMBERS(2)    System Calls Manual   IOCTL-XFS-FSINUMBERS(2)

NAME         top

       ioctl_xfs_fsinumbers - extract a list of valid inode numbers from
       an XFS filesystem

SYNOPSIS         top

       #include <xfs/xfs_fs.h>

       int ioctl(int fd, XFS_IOC_FSINUMBERS, struct xfs_fsop_bulkreq
       *arg);

DESCRIPTION         top

       Queries inode allocation information from an XFS filesystem.  It
       is intended to be called iteratively to obtain the entire set of
       inodes.  These ioctls use struct xfs_fsop_bulkreq to set up a
       bulk transfer with the kernel:

           struct xfs_fsop_bulkreq {
                __u64   *lastip;
                __s32   count;
                void    *ubuffer;
                __s32   *ocount;
           };

       lastip points to a value that will receive the number of the
       "last inode."  This should be set to one less than the number of
       the first inode for which the caller wants information, or zero
       to start with the first inode in the filesystem.  After the call,
       this value will be set to the number of the last inode for which
       information is supplied.  This field will not be updated if
       ocount is NULL.

       count is the number of elements in the ubuffer array and
       therefore the number of inode groups for which to return
       allocation information.

       ocount points to a value that will receive the number of records
       returned.  An output value of zero means that there are no more
       inode groups left to enumerate.  If this value is NULL, then
       neither ocount nor lastip will be updated.

       ubuffer points to a memory buffer where inode group information
       will be copied.  This buffer must be an array of struct
       xfs_inogrp which is described below.  The array must have at
       least count elements.

           struct xfs_inogrp {
                __u64   xi_startino;
                __s32   xi_alloccount;
                __u64   xi_allocmask;
           }

       This structure describes inode usage information for a group of
       64 consecutive inode numbers.  The fields are as follows:

       xi_startino is the first inode number of this group.

       xi_alloccount is the number of bits that are set in xi_allocmask.
       This is the number of inodes allocated in this group.

       xi_allocmask is a bitmask of inodes that are allocated in this
       inode group.  The bitmask is 64 bits long, and the least
       significant bit corresponds to inode xi_startino.

RETURN VALUE         top

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

ERRORS         top

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

       EFAULT The kernel was not able to copy into the userspace buffer.

       EFSBADCRC
              Metadata checksum validation failed while performing the
              query.

       EFSCORRUPTED
              Metadata corruption was encountered while performing the
              query.

       EINVAL One of the arguments was not valid.

       EIO    An I/O error was encountered while performing the query.

       ENOMEM There was insufficient memory to perform the query.

CONFORMING TO         top

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

SEE ALSO         top

       ioctl(2)

COLOPHON         top

       This page is part of the xfsprogs (utilities for XFS filesystems)
       project.  Information about the project can be found at 
       ⟨http://xfs.org/⟩.  If you have a bug report for this manual page,
       send it to linux-xfs@vger.kernel.org.  This page was obtained
       from the project's upstream Git repository
       ⟨https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git⟩ on
       2021-08-27.  (At that time, the date of the most recent commit
       that was found in the repository was 2021-08-20.)  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to man-pages@man7.org

XFS                            2019-06-17        IOCTL-XFS-FSINUMBERS(2)

Pages that refer to this page: xfsctl(3)