[PATCH 06/12] man: document the new allocation group geometry ioctl

From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: sandeen@sandeen.net, darrick.wong@oracle.com
Cc: linux-xfs@vger.kernel.org
Subject: [PATCH 06/12] man: document the new allocation group geometry ioctl
Date: Tue, 20 Aug 2019 13:31:48 -0700	[thread overview]
Message-ID: <156633310832.1215978.10494838202211430225.stgit@magnolia> (raw)
In-Reply-To: <156633307176.1215978.17394956977918540525.stgit@magnolia>

From: Darrick J. Wong <darrick.wong@oracle.com>

Document the new ioctl to describe an allocation group's geometry.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 man/man2/ioctl_xfs_ag_geometry.2 |   74 ++++++++++++++++++++++++++++++++++++++
 man/man3/xfsctl.3                |    6 +++
 2 files changed, 80 insertions(+)
 create mode 100644 man/man2/ioctl_xfs_ag_geometry.2

diff --git a/man/man2/ioctl_xfs_ag_geometry.2 b/man/man2/ioctl_xfs_ag_geometry.2
new file mode 100644
index 00000000..5dfe0d08
--- /dev/null
+++ b/man/man2/ioctl_xfs_ag_geometry.2
@@ -0,0 +1,74 @@
+.\" Copyright (c) 2019, Oracle.  All rights reserved.
+.\"
+.\" %%%LICENSE_START(GPLv2+_DOC_FULL)
+.\" SPDX-License-Identifier: GPL-2.0+
+.\" %%%LICENSE_END
+.TH IOCTL-XFS-AG-GEOMETRY 2 2019-04-11 "XFS"
+.SH NAME
+ioctl_xfs_ag_geometry \- query XFS allocation group geometry information
+.SH SYNOPSIS
+.br
+.B #include <xfs/xfs_fs.h>
+.PP
+.BI "int ioctl(int " fd ", XFS_IOC_AG_GEOMETRY, struct xfs_ag_geometry *" arg );
+.SH DESCRIPTION
+This XFS ioctl retrieves the geometry information for a given allocation group.
+The geometry information is conveyed in a structure of the following form:
+.PP
+.in +4n
+.nf
+struct xfs_ag_geometry {
+	uint32_t  ag_number;
+	uint32_t  ag_length;
+	uint32_t  ag_freeblks;
+	uint32_t  ag_icount;
+	uint32_t  ag_ifree;
+	uint32_t  ag_sick;
+	uint32_t  ag_checked;
+	uint32_t  ag_reserved32;
+	uint64_t  ag_reserved[12];
+};
+.fi
+.in
+.TP
+.I ag_number
+The number of allocation group that the caller wishes to learn about.
+.TP
+.I ag_length
+Length of the allocation group, in units of filesystem blocks.
+.TP
+.I ag_freeblks
+Number of free blocks in the allocation group, in units of filesystem blocks.
+.TP
+.I ag_icount
+Number of inode records allocated in this allocation group.
+.TP
+.I ag_ifree
+Number of unused inode records (of the space allocated) in this allocation
+group.
+.TP
+.IR ag_reserved " and " ag_reserved32
+Will be set to zero.
+.SH RETURN VALUE
+On error, \-1 is returned, and
+.I errno
+is set to indicate the error.
+.PP
+.SH ERRORS
+Error codes can be one of, but are not limited to, the following:
+.TP
+.B EFSBADCRC
+Metadata checksum validation failed while performing the query.
+.TP
+.B EFSCORRUPTED
+Metadata corruption was encountered while performing the query.
+.TP
+.B EINVAL
+The specified allocation group number is not valid for this filesystem.
+.TP
+.B EIO
+An I/O error was encountered while performing the query.
+.SH CONFORMING TO
+This API is specific to XFS filesystem on the Linux kernel.
+.SH SEE ALSO
+.BR ioctl (2)
diff --git a/man/man3/xfsctl.3 b/man/man3/xfsctl.3
index 7e6588b8..dfebd12d 100644
--- a/man/man3/xfsctl.3
+++ b/man/man3/xfsctl.3
@@ -336,6 +336,12 @@ See
 .BR ioctl_xfs_fsop_geometry (2)
 for more information.
 
+.TP
+.B XFS_IOC_AG_GEOMETRY
+See
+.BR ioctl_xfs_ag_geometry (2)
+for more information.
+
 .TP
 .BR XFS_IOC_FSBULKSTAT " or " XFS_IOC_FSBULKSTAT_SINGLE
 See

