We want to address the case that we have printed the last useful
stats line already within the loop. Avoiding an additional line
"Discarded 0 bytes ..." at the end.
Note there is a behavior change now for the edge cases "-v -l 0" and
"-v -o blksize" where we don't print any stats line anymore. But actually
it's correct, we never make any BLKDISCARD syscall with zero range.
Perhaps we should return error in these cases to help people who always
want to parse stats output on success.
CC: Federico Simoncelli <fsimonce@redhat.com>
Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
We will see if this makes our "--step" tests reliable.
CC: Federico Simoncelli <fsimonce@redhat.com>
Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
The message "stat failed %s" seems to say that stat() failed to
do something, or failed to pass a test, but of course it means
that the statting of something failed. So say so. Also make
two very similar messages equal to this one.
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>
This adds a concise description of a tool to its usage text.
A first form of this patch was proposed by Steven Honeyman
(see http://www.spinics.net/lists/util-linux-ng/msg09994.html).
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>
If offset (range[0]) is greater than device size (blksize), the variable 'end'
will be greater than blksize, and range[1] (length) will be recalculated.
The underflow happens when subtracting range[0] (offset) from blksize, thus
range[1] will be the result of an underflow. The bug leads to unwanted behavior
from the program, where range[1] is likely to be a high number and then will
discard a considerable amount of blocks from the device. The fix consists of
exitting the program with an error message when the condition stated above is
true. Spotted while auditing the code.
Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Calling function "open(char const *, int, ...)" that uses "path" after
a check function. This can cause a time-of-check, time-of-use race
condition.
.. well, in blkdiscard context it's mostly cosmetic change.
Signed-off-by: Karel Zak <kzak@redhat.com>
blkdiscard is used to discard device sectors. This is useful for
solid-state drivers (SSDs) and thinly-provisioned storage. Unlike
fstrim this command is used directly on the block device.
blkkdiscard uses BLKDISCARD ioctl or BLKSECDISCARD ioctl for the secure
discard.
All data in the discarded region on the device will be lost!
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Karel Zak
Benno Schulenberg
Ruediger Meier
Sami Kerola
Federico Simoncelli
Raphael S. Carvalho
Theodore Ts'o
Lukas Czerner