ioctl_xfs_fsinumbers(2) — Linux manual page



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

       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.

              Metadata checksum validation failed while performing the

              Metadata corruption was encountered while performing the

       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


COLOPHON         top

       This page is part of the xfsprogs (utilities for XFS filesystems)
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       ⟨⟩ on
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XFS                              2019-06-17          IOCTL-XFS-FSINUMBERS(2)

Pages that refer to this page: xfsctl(3)