When a scrub completes or is cancelled, statistics are updated for
reporting in a later btrfs scrub status command and for resuming the
scrub. Most statistics (such as bytes scrubbed) are additive so scrub
adds the statistics from the current run to the saved statistics.
However, the last_physical statistic is not additive. The value from the
current run should replace the saved value. The current code incorrectly
adds the last_physical from the current run to the previous saved value.
This bug causes the resume point to be incorrectly recorded, so large
areas of the disk are skipped when the scrub resumes. As an example,
assume a disk had 1000000 bytes and scrub was cancelled and resumed each
time 10% (100000 bytes) had been scrubbed.
Run | Start byte | bytes scrubbed | kernel last_physical | saved last_physical
1 | 0 | 100000 | 100000 | 100000
2 | 100000 | 100000 | 200000 | 300000
3 | 300000 | 100000 | 400000 | 700000
4 | 700000 | 100000 | 800000 | 1500000
5 | 1500000 | 0 | immediately completes| completed
In this example, only 40% of the disk is actually scrubbed.
This patch changes the saved/displayed last_physical to track the last
reported value from the kernel.
Signed-off-by: Graham R. Cobb <g.btrfs@cobb.uk.net>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds a global --format option to request extended output formats
from each command.
We currently only support text mode. Command help reports what
output formats are available for each command. Global help reports
what valid formats are.
If an invalid format is requested, an error is reported and lists the
valid formats.
Each command sets a bitmask that describes which formats it is capable
of outputting. If a globally valid format is requested of a command
that doesn't support it, an error is reported and command usage dumped.
Commands don't need to specify that they support text output. All
commands are required to output text.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
[ use global config instead of passing cmd_context ]
Signed-off-by: David Sterba <dsterba@suse.com>
For options that do not have the long description, the empty string is
required to mark where the options start. Some commands were missing
that.
Signed-off-by: David Sterba <dsterba@suse.com>
This is first instance of commands files moving to a separate directory,
that will be cmds/, thus the files can drop the prefix. We can further
split files into specific parts of a given command. The quota file was
selected as the smallest.
Signed-off-by: David Sterba <dsterba@suse.com>
