* do not ignore all empty devices, we need more smart solution
* ignore only loop devices without backing file, for example:
# touch img
# losetup -f img
losetup: img: Warning: file is smaller than 512 bytes; the loop device may be useless or invisible for system tools.
- old version display nothing
- new version:
# lsblk /dev/loop0
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
loop0 7:0 0 0B 0 loop
Addresses: https://github.com/karelzak/util-linux/issues/1118
Signed-off-by: Karel Zak <kzak@redhat.com>
The partition scanner in kernel depends on blocksize. We need to set
the blocksize before we call LOOP_SET_STATUS64 (this ioctl triggers
the scanner).
This patch extends the internal API to save blocksize into loopdev
context to be usable later for loopcxt_setup_device().
Signed-off-by: Karel Zak <kzak@redhat.com>
Now the internal API uses loopcxt_set_...() to set context variables
as well as to call ioctls. This patch introduces loopcxt_ioctl_...()
to makes things more obvious to readers.
Signed-off-by: Karel Zak <kzak@redhat.com>
Kernel since 4.14 supports setting of logical block size[1]. It allows to
create loop devices that report logical block size different from 512.
Add support for this feature to losetup.
References:
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/block/loop.c?id=89e4fdecb51cf5535867026274bc97de9480ade5
[kzak@redhat.com: - fix loopcxt_get_blocksize()
- remove lo_blocksize from loop_info64]
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Karel Zak <kzak@redhat.com>
Implement stand-alone loopcxt_set_status(). It allows manipulation with some
loop device parameters even if it is initialized.
Its function is limited by the kernel implementation, and only a small subset of
changes is allowed.
For more see linux/drivers/block/loop.c:loop_set_status()
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
Fully safe checks of loop device need to check sizelimit. To prevent need of two
nearly equal functions, introduce sizelimit parameter to several internal
functions:
loopdev_is_used()
loopdev_find_by_backing_file()
loopcxt_is_used()
loopcxt_find_by_backing_file()
If sizelimit is zero, fall back to the old behavior (ignoring of sizelimit).
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
From v4.4, linux kernel starts to support direct I/O and
AIO to backing file for loop driver, so allow losetup to
enable the feature by using LOOP_SET_DIRECT_IO ioctl cmd.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
On system with /dev/lop-control the udevd creates /dev/loopN nodes.
It seems better to wait a moment after unsuccessful open(/dev/loopN)
and try it to open again.
The problem is pretty visible on systems where udevd also modifies
permission for loopN devices, then open() fails with EACCES when
losetup executed by non-root user (but user who is in "disk" group).
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1045432
Signed-off-by: Karel Zak <kzak@redhat.com>
Now we use LOOP_CTL_GET_FREE ioctl to ask for free device, for example
losetup -f foo.img
Unfortunately, losetup(8) allows to ask for specified device
losetup /dev/loop100 foo.img
and in this case we assume that the device already exists in the
system. This is incorrect, we should be able to use loop-control
LOOP_CTL_ADD ioctl to ask for the specified device.
Signed-off-by: Karel Zak <kzak@redhat.com>
I recently tried to mount an hfsplus file system from an image file with
a partition table by using the loop offset and sizelimit options to specify
the location of the file system.
hfsplus stores some metadata at a set offset from the end of the partition,
so it's sensitive to the device size reported by the kernel.
It worked with this:
But failed with this:
/dev/loop0: [0089]:2 (<imagefile>), offset 32768, sizelimit 102400000
/dev/loop1: [0089]:2 (<imagefile>), offset 32768, sizelimit 102400000
/proc/partitions shows the correct number of blocks to match the sizelimit.
But if I set a breakpoint in mount before the mount syscall, I could see:
102400000
102432768
The kernel loop driver will set the gendisk capacity of the device at
LOOP_SET_STATUS64 but won't sync it to the block device until one of two
conditions are met: All open file descriptors referring to the device are
closed (and it will sync when re-opened) or if the LOOP_SET_CAPACITY ioctl
is called to sync it. Since mount opens the device and passes it directly
to the mount syscall after LOOP_SET_STATUS64 without closing and reopening
it, the sizelimit argument is effectively ignroed. The capacity needs to
be synced immediately for it to work as expected.
This patch adds the LOOP_SET_CAPACITY call to loopctx_setup_device since
the device isn't yet released to the user, so it's safe to sync the capacity
immediately.
[kzak@redhat.com: - port to the current git HEAD,
- use uint64_t]
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
kernel cryptoloop is deprecated since ages and support for cryptoloop
in util-linux is incomplete/broken.
- no password hashing
- last 8 bit of key are always set to zero
- no binary keys possible (stops reading key at \n and \0)
In the past some Distros added the above features with patches. So
remove cryptoloop support from util-linux completely to make sure
people won't try using it.
Signed-off-by: Ludwig Nussel <ludwig.nussel@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
# ll ~/xxx2
-rw-r--r-- 1 root root 500 Jun 12 14:30 /root/xxx2
old version:
# losetup -a
new version:
# losetup -a
/dev/loop0: [2052]:535312 (/root/xxx2)
The new version scans /sys/block/loopN, kernel >= 2.6.37 is required
otherwise fallback to the original not-so-smart /proc/partitions scan.
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=730266
Signed-off-by: Karel Zak <kzak@redhat.com>
- improve loop_info usage (don't call ioctl more than once)
- add functions to get devno and inode of the backing file
- add function for compare any file with backing file by devno + inode
or by filename
Signed-off-by: Karel Zak <kzak@redhat.com>
Karel Zak
Sinan Kaya
Stanislav Brabec
Ming Lei
Lauri Nurmi
Jeff Mahoney
Ludwig Nussel
Dave Reisner