Make it possible to unmount a filesystem on a loop device if it is
specified by associated backing file. It does not attempt to unmount
anything if there are more than one loop device associated with the
given file.
Umount looks for associated loopdevice(s) only if umount is called
with the regular file as an argument.
Before:
mount -o loop -t ext2 img mnt
umount -v img
> Could not find /home/puzel/upstream/util-linux/img in mtab
> umount: img: not mounted
After:
mount -o loop -t ext2 img mnt
umount -v img
> img is associated with /dev/loop0, trying to unmount it
> /dev/loop0 has been unmounted
[kzak@redhat.com: - fix memory leak in lomount.c]
Addresses: https://bugzilla.novell.com/show_bug.cgi?id=666161
Signed-off-by: Petr Uzel <petr.uzel@suse.cz>
Signed-off-by: Karel Zak <kzak@redhat.com>
On systems without /etc/mtab (or everywhere if kernel >= 2.6.37)
we use loop autoclear flag and then the backing file name is not
stored in /etc/mtab. mount(8) uses sysfs to get the filename (or
LOOP_GET_STATU* ioctls on old kernels).
Signed-off-by: Karel Zak <kzak@redhat.com>
The basic loopdev attributes are available in sysfs since kernel
2.6.37. This patch uses the backing_file attribute from sysfs for very
long filenames (the LOOP_GET_STATUS ioctl uses only 64 bytes for the
filename).
old version:
# losetup -a
/dev/loop0: [0804]:12865322 (/home/images/filesystems/this_is_really_really_long_directory_*)
new version:
# losetup -a
/dev/loop0: [0804]:12865322 (/home/images/filesystems/this_is_really_really_long_directory_name/ext2.img)
Signed-off-by: Karel Zak <kzak@redhat.com>
This patch replaces a few functions used throughout the source:
* Renames getnum (from schedutils) to strtol_or_err
* Moves strtosize (from lib/strtosize.c)
* Moves xstrncpy (from include/xstrncpy.h)
* Adds strnlen, strnchr and strndup if not available (remove it from libmount utils)
A few Makefile.am files were modified to compile accordingly along with trivial renaming
in schedutils source code.
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
realloc(NULL, size) behaves the same as malloc(size) so there is no need
to distinguish between the two.
[kzak@redhat.com: - better handle realloc() errors]
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Karel Zak <kzak@redhat.com>
The loop_scandir() expects all the files in /dev/loop/ to be actual
devices and not symlinks to devices. However, udev by default sets up
symlinks in /dev/loop/ thereby breaking the fallback scan logic when
looking for devices more than the default number of 8.
Simple way to reproduce is:
- <detach all devices>
- cd /dev/loop
- rm -f [2-7]
- losetup 0 autogen.sh
- mv 1 8
- for n in {1..7} ; do ln -s 0 $n ; done
- losetup -f
<error but should have found /dev/loop/8>
[kay.sievers@vrfy.org:
just a note, udev does not do that by default. It is
devfs-nonsense, which the "default" never did.]
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Reported-by: Mario Bachmann <grafgrimm77@gmx.de>
Based on
fix-hang-on-stale-nfs.diff
from SUSE src.rpm package.
It seems better to more precisely check for ENXIO rather than assume
that all LOOP_GET_STATUS errors mean that the device is not used.
Addresses-Novell-Bugzilla: #449646
Signed-off-by: Karel Zak <kzak@redhat.com>
This patch allows to detach more devices by "losetup -d",
for example:
# losetup -a
/dev/loop0: [0804]:9955739 (/home/images/ary0.img)
/dev/loop1: [0804]:9955740 (/home/images/ary1.img)
/dev/loop2: [0804]:9955745 (/home/images/ary2.img)
# losetup -d /dev/loop0 /dev/loop1 /dev/loop2
Signed-off-by: Karel Zak <kzak@redhat.com>
Currently mounting/losetup an image fails if it is accessable readonly.
There are no problems if it is a file on a local filesystem.
It seems only to happen if it is a NFS mounted image, which is
read-write in permission but with root_squash option.
set_loop checks only for EROFS to retry open with readonly mode,
but in this case we get EACCES.
Signed-off-by: Matthias Koenig <mkoenig@suse.de>
The latest kernel supports partitioned loop devices (kernel commit
476a4813cfddf7cf159956cc0e2d3c830c1507e3). Unfortunately, this change
makes minor numbers useless, because mirror number does not match with
loop device name (loop<N>).
We have to follow loop device names only.
Signed-off-by: Karel Zak <kzak@redhat.com>
This patch replaces scandir-based implementation with readdir(). The
readdir(3) is less expensive and more portable (to non-glibc environment).
The patch also replaces sysfs-based solution with simpler /proc/partitions
parsing. The /proc/partitions includes all used loop devices on all systems
(include 2.4). This solution seems faster than scandir(/sys/block/) too.
Summary, the losetup (with this patch) uses three methods to found a
loop device:
a) parse /proc/partitions to found already used loop devices (for
loserup -a)
b) stat(2) for all loop[0-7] devices (default number of loop devices).
This is classic method from util-linux <= 2.13. This method is good
enough for standard Linux machines with default number of loop
devices.
c) scan all /dev or /dev/loop/ for loop devices. This is useful for
crazy people who need more than 8 loop devices.
Signed-off-by: Karel Zak <kzak@redhat.com>
The new loop auto-destruct feature detaches automatically loop devices
when no longer used. This means they are detached with the umount()
call. But when we call umount with -d, del_loop() is called and fails
because the ioctl() returns ENXIO. We have to check for autoclear
loop devices rather than blindly call del_loop().
Reported-by: Matthias Koenig <mkoenig@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
As it has already changed since the previous release, take the opportunity
to cut it into two more manageable chunks for translators.
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>
Signed-off-by: Karel Zak <kzak@redhat.com>
[kzak@redhat.com: split the original patch to small patches]
Signed-off-by: Shachar Shemesh <shachar@debian.org>
Signed-off-by: Karel Zak <kzak@redhat.com>
This allows a flag to be set on loop devices so that when they are closed
for the last time, they'll self-destruct.
The kernel part has been submitted to lkml by David Woodhouse.
Signed-off-by: Bernardo Innocenti <bernie@codewiz.org>
Signed-off-by: Karel Zak <kzak@redhat.com>
Old implementation:
- supports 256 loop devices only
- doesn't support gaps in list of loop devices
(e.g. loop0, loop1, loop3 -- loop3 is invisible)
Kernel 2.6.21 removes artificial maximum 256 loop device. Now the maximum
of loop devices could be really huge (depends on limit of MINOR
numbers). It means we need a better way how work with loop devices
than blindly call stat(2) for all 0-1048575 devices.
This patch uses three methods:
a) scan /sys/block/loopN (used for losetup -a only). This method is
probably the fastest way how found used loop device on machine with
huge number of devices in /dev.
b) classic way, stat(2) for all loop[0-7] devices (default number of
loop devices). This cheap method is sufficient for 99% of all machines.
c) scan all /dev/loopN or /dev/loop/N
Signed-off-by: Karel Zak <kzak@redhat.com>
The kernel loop_info64 definition uses __u{8,32,64} types,
but userspace uses unsigned {long long,int,char} types.
This patch turns into exactly defined standard uint{8,32,64}_t types.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Karel Zak <kzak@redhat.com>
The mount syscall prevents mounting the same device twice
to the same mountpoint. When loop mounting a file, for each
file a new loop device gets allocated, which prevents the detection
of loop mounting the same file to the same mountpoint twice.
The patch adds a check to prevent double mounts, if the same loopfile
is going to be mounted with the same offset to the same mountpoint.
Co-Author: Matthias Koenig <mkoenig@suse.de>
Signed-off-by: Matthias Koenig <mkoenig@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
When setting up a loop device, canonicalize the loop file
name. This simplifies a later identification of loop file names
when querying the loop devices.
Co-Author: Matthias Koenig <mkoenig@suse.de>
Signed-off-by: Matthias Koenig <mkoenig@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
Karel Zak
Petr Uzel
Davidlohr Bueso
Andreas Schwab
Tobias Klauser
Mike Frysinger
Matthias Koenig
Pedro Ribeiro
Benno Schulenberg
Shachar Shemesh
Bernardo Innocenti
Samuel Thibault