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diff --git a/upstream/archlinux/man8/btrfs-check.8 b/upstream/archlinux/man8/btrfs-check.8 new file mode 100644 index 00000000..59d0a764 --- /dev/null +++ b/upstream/archlinux/man8/btrfs-check.8 @@ -0,0 +1,230 @@ +.\" Man page generated from reStructuredText. +. +. +.nr rst2man-indent-level 0 +. +.de1 rstReportMargin +\\$1 \\n[an-margin] +level \\n[rst2man-indent-level] +level margin: \\n[rst2man-indent\\n[rst2man-indent-level]] +- +\\n[rst2man-indent0] +\\n[rst2man-indent1] +\\n[rst2man-indent2] +.. +.de1 INDENT +.\" .rstReportMargin pre: +. RS \\$1 +. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin] +. nr rst2man-indent-level +1 +.\" .rstReportMargin post: +.. +.de UNINDENT +. RE +.\" indent \\n[an-margin] +.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]] +.nr rst2man-indent-level -1 +.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]] +.in \\n[rst2man-indent\\n[rst2man-indent-level]]u +.. +.TH "BTRFS-CHECK" "8" "Feb 14, 2024" "6.7.1" "BTRFS" +.SH NAME +btrfs-check \- check or repair a btrfs filesystem +.SH SYNOPSIS +.sp +\fBbtrfs check\fP [options] <device> +.SH DESCRIPTION +.sp +The filesystem checker is used to verify structural integrity of a filesystem +and attempt to repair it if requested. It is recommended to unmount the +filesystem prior to running the check, but it is possible to start checking a +mounted filesystem (see \fI\%\-\-force\fP). +.sp +By default, \fBbtrfs check\fP will not modify the device but you can reaffirm that +by the option \fI\-\-readonly\fP\&. +.sp +\fBbtrfsck\fP is an alias of \fBbtrfs check\fP command and is now deprecated. +.sp +\fBWARNING:\fP +.INDENT 0.0 +.INDENT 3.5 +Do not use \fI\-\-repair\fP unless you are advised to do so by a developer +or an experienced user, and then only after having accepted that no \fIfsck\fP +successfully repair all types of filesystem corruption. E.g. some other software +or hardware bugs can fatally damage a volume. +.UNINDENT +.UNINDENT +.sp +The structural integrity check verifies if internal filesystem objects or +data structures satisfy the constraints, point to the right objects or are +correctly connected together. +.sp +There are several cross checks that can detect wrong reference counts of shared +extents, backreferences, missing extents of inodes, directory and inode +connectivity etc. +.sp +The amount of memory required can be high, depending on the size of the +filesystem, similarly the run time. Check the modes that can also affect that. +.SH SAFE OR ADVISORY OPTIONS +.INDENT 0.0 +.TP +.B \-b|\-\-backup +use the first valid set of backup roots stored in the superblock +.sp +This can be combined with \fI\-\-super\fP if some of the superblocks are damaged. +.UNINDENT +.INDENT 0.0 +.TP +.B \-\-check\-data\-csum +verify checksums of data blocks +.sp +This expects that the filesystem is otherwise OK, and is basically an offline +\fIscrub\fP that does not repair data from spare copies. +.TP +.BI \-\-chunk\-root \ <bytenr> +use the given offset \fIbytenr\fP for the chunk tree root +.UNINDENT +.INDENT 0.0 +.TP +.B \-E|\-\-subvol\-extents <subvolid> +show extent state for the given subvolume +.UNINDENT +.INDENT 0.0 +.TP +.BI \-\-mode \ <MODE> +select mode of operation regarding memory and IO +.sp +The \fIMODE\fP can be one of: +.INDENT 7.0 +.TP +.B original +The metadata are read into memory and verified, thus the requirements are high +on large filesystems and can even lead to out\-of\-memory conditions. The +possible workaround is to export the block device over network to a machine +with enough memory. +.TP +.B lowmem +This mode is supposed to address the high memory consumption at the cost of +increased IO when it needs to re\-read blocks. This may increase run time. +.UNINDENT +.UNINDENT +.INDENT 0.0 +.TP +.B \-p|\-\-progress +indicate progress at various checking phases +.TP +.B \-Q|\-\-qgroup\-report +verify qgroup accounting and compare against filesystem accounting +.TP +.B \-r|\-\-tree\-root <bytenr> +use the given offset \(aqbytenr\(aq for the tree root +.UNINDENT +.INDENT 0.0 +.TP +.B \-\-readonly +(default) +run in read\-only mode, this option exists to calm potential panic when users +are going to run the checker +.UNINDENT +.INDENT 0.0 +.TP +.B \-s|\-\-super <N> +use Nth superblock copy, valid values are 0, 1 or 2 if the +respective superblock offset is within the device size +.sp +This can be used to use a different starting point if some of the primary +superblock is damaged. +.TP +.B \-\-clear\-space\-cache v1|v2 +completely remove the free space cache of the given version +.sp +See also the \fIclear_cache\fP mount option. +.sp +\fBWARNING:\fP +.INDENT 7.0 +.INDENT 3.5 +This option is deprecated, please use \fIbtrfs rescue clear\-space\-cache\fP +instead, this option would be removed in the future eventually. +.UNINDENT +.UNINDENT +.UNINDENT +.SH DANGEROUS OPTIONS +.INDENT 0.0 +.TP +.B \-\-repair +enable the repair mode and attempt to fix problems where possible +.sp +\fBNOTE:\fP +.INDENT 7.0 +.INDENT 3.5 +There\(aqs a warning and 10 second delay when this option is run without +\fI\-\-force\fP to give users a chance to think twice before running repair, the +warnings in documentation have shown to be insufficient. +.UNINDENT +.UNINDENT +.TP +.B \-\-init\-csum\-tree +create a new checksum tree and recalculate checksums in all files +.sp +\fBWARNING:\fP +.INDENT 7.0 +.INDENT 3.5 +Do not blindly use this option to fix checksum mismatch problems. +.UNINDENT +.UNINDENT +.TP +.B \-\-init\-extent\-tree +build the extent tree from scratch +.sp +\fBWARNING:\fP +.INDENT 7.0 +.INDENT 3.5 +Do not use unless you know what you\(aqre doing. +.UNINDENT +.UNINDENT +.UNINDENT +.INDENT 0.0 +.TP +.B \-\-force +allow work on a mounted filesystem and skip mount checks. Note that +this should work fine on a quiescent or read\-only mounted filesystem +but may crash if the device is changed externally, e.g. by the kernel +module. +.sp +\fBNOTE:\fP +.INDENT 7.0 +.INDENT 3.5 +It is possible to run with \-\-repair but on a mounted filesystem +that will most likely lead to a corruption unless the filesystem +is in a quiescent state which may not be possible to guarantee. +.UNINDENT +.UNINDENT +.sp +This option also skips the delay and warning in the repair mode (see +\fI\-\-repair\fP). +.UNINDENT +.SH DEPRECATED OR MOVED OPTIONS +.INDENT 0.0 +.TP +.B \-\-clear\-ino\-cache +(removed: 6.7) +.sp +remove leftover items pertaining to the deprecated \fIinode cache\fP feature, +please use \fI\%btrfs rescue clear\-ino\-cache\fP +instead +.UNINDENT +.SH EXIT STATUS +.sp +\fBbtrfs check\fP returns a zero exit status if it succeeds. Non zero is +returned in case of failure. +.SH AVAILABILITY +.sp +\fBbtrfs\fP is part of btrfs\-progs. Please refer to the documentation at +\fI\%https://btrfs.readthedocs.io\fP\&. +.SH SEE ALSO +.sp +\fI\%mkfs.btrfs(8)\fP, +\fI\%btrfs\-scrub(8)\fP, +\fI\%btrfs\-rescue(8)\fP +.\" Generated by docutils manpage writer. +. |