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Diffstat (limited to 'man/man5/proc_pid_mountinfo.5')
| -rw-r--r-- | man/man5/proc_pid_mountinfo.5 | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/man/man5/proc_pid_mountinfo.5 b/man/man5/proc_pid_mountinfo.5 new file mode 100644 index 0000000..c43e0e6 --- /dev/null +++ b/man/man5/proc_pid_mountinfo.5 @@ -0,0 +1,124 @@ +.\" Copyright (C) 1994, 1995, Daniel Quinlan <quinlan@yggdrasil.com> +.\" Copyright (C) 2002-2008, 2017, Michael Kerrisk <mtk.manpages@gmail.com> +.\" Copyright (C) 2023, Alejandro Colomar <alx@kernel.org> +.\" +.\" SPDX-License-Identifier: GPL-3.0-or-later +.\" +.TH proc_pid_mountinfo 5 2024-05-02 "Linux man-pages (unreleased)" +.SH NAME +/proc/pid/mountinfo \- mount information +.SH DESCRIPTION +.TP +.IR /proc/ pid /mountinfo " (since Linux 2.6.26)" +.\" This info adapted from Documentation/filesystems/proc.txt +.\" commit 2d4d4864ac08caff5c204a752bd004eed4f08760 +This file contains information about mounts +in the process's mount namespace (see +.BR mount_namespaces (7)). +It supplies various information +(e.g., propagation state, root of mount for bind mounts, +identifier for each mount and its parent) that is missing from the (older) +.IR /proc/ pid /mounts +file, and fixes various other problems with that file +(e.g., nonextensibility, +failure to distinguish per-mount versus per-superblock options). +.IP +The file contains lines of the form: +.IP +.EX +36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 \- ext3 /dev/root rw,errors=continue +(1)(2)(3) (4) (5) (6) (7) (8) (9) (10) (11) +.EE +.IP +The numbers in parentheses are labels for the descriptions below: +.RS 7 +.TP 5 +(1) +mount ID: a unique ID for the mount (may be reused after +.BR umount (2)). +.TP +(2) +parent ID: the ID of the parent mount +(or of self for the root of this mount namespace's mount tree). +.IP +If a new mount is stacked on top of a previous existing mount +(so that it hides the existing mount) at pathname P, +then the parent of the new mount is the previous mount at that location. +Thus, when looking at all the mounts stacked at a particular location, +the top-most mount is the one that is not the parent +of any other mount at the same location. +(Note, however, that this top-most mount will be accessible only if +the longest path subprefix of P that is a mount point +is not itself hidden by a stacked mount.) +.IP +If the parent mount lies outside the process's root directory (see +.BR chroot (2)), +the ID shown here won't have a corresponding record in +.I mountinfo +whose mount ID (field 1) matches this parent mount ID +(because mounts that lie outside the process's root directory +are not shown in +.IR mountinfo ). +As a special case of this point, +the process's root mount may have a parent mount +(for the initramfs filesystem) that lies +.\" Miklos Szeredi, Nov 2017: The hidden one is the initramfs, I believe +.\" mtk: In the initial mount namespace, this hidden ID has the value 0 +outside the process's root directory, +and an entry for that mount will not appear in +.IR mountinfo . +.TP +(3) +major:minor: the value of +.I st_dev +for files on this filesystem (see +.BR stat (2)). +.TP +(4) +root: the pathname of the directory in the filesystem +which forms the root of this mount. +.TP +(5) +mount point: the pathname of the mount point relative +to the process's root directory. +.TP +(6) +mount options: per-mount options (see +.BR mount (2)). +.TP +(7) +optional fields: zero or more fields of the form "tag[:value]"; see below. +.TP +(8) +separator: the end of the optional fields is marked by a single hyphen. +.TP +(9) +filesystem type: the filesystem type in the form "type[.subtype]". +.TP +(10) +mount source: filesystem-specific information or "none". +.TP +(11) +super options: per-superblock options (see +.BR mount (2)). +.RE +.IP +Currently, the possible optional fields are +.IR shared , +.IR master , +.IR propagate_from , +and +.IR unbindable . +See +.BR mount_namespaces (7) +for a description of these fields. +Parsers should ignore all unrecognized optional fields. +.IP +For more information on mount propagation see +.I Documentation/filesystems/sharedsubtree.rst +(or +.I Documentation/filesystems/sharedsubtree.txt +before Linux 5.8) +in the Linux kernel source tree. +.SH SEE ALSO +.BR proc (5) |