btrfs provides a helpful demonstration of how to export
a global variable via debugfs; however, it is unique among
other debugfs files in that it is world-writable, which causes
some concern to people who are not familiar with its purpose.
Fix it so that it is only user-writable.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If the label setting ioctl races with sysfs label handler, we could get
mixed result in the output, part old part new. We should either get the
old or new label. The chances to hit this race are low.
Signed-off-by: David Sterba <dsterba@suse.com>
Add a sanity check for the fs_info as we will dereference it, similar to
what the 'store features' handler does.
Signed-off-by: David Sterba <dsterba@suse.com>
If the mount phase is not finished, we can't update the sysfs files.
Reported-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The files under /sys/fs/UUID/features get out of sync with the actual
incompat bits set for the filesystem if they change after mount. We're
going to sync them and need a helper to do that.
Signed-off-by: David Sterba <dsterba@suse.com>
The incompat bit representing the newly added free space tree feature is
missing. Right now it will be listed only among features supported by
the module, not per-fs.
Signed-off-by: David Sterba <dsterba@suse.com>
To support seed sysfs layout and represent seed fsid under
the sprout we need the facility to create fsid under the
specified parent.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
btrfs_kobj_add_device() does not need fs_info any more.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Just a helper function to clean up the sysfs fsid kobjects.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
This patch will provide a framework and help to create attributes
from the structure btrfs_fs_devices which are available even before
fs_info is created. So by moving the parent kobject super_kobj from
fs_info to btrfs_fs_devices, it will help to create attributes
from the btrfs_fs_devices as well.
Patches on top of this patch now will be able to create the
sys/fs/btrfs/fsid kobject and attributes from btrfs_fs_devices
when devices are scanned and registered to the kernel.
Just to note, this does not change any of the existing btrfs sysfs
external kobject names and its attributes and not even the life
cycle of them. Changes are internal only. And to ensure the same,
this path has been tested with various device operations and,
checking and comparing the sysfs kobjects and attributes with
sysfs kobject and attributes with out this patch, and they remain
same.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Separate device kobject and its attribute creation so that device
kobject can be created from the device discovery thread.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
As of now btrfs_attrs are provided using the default_attrs through
the kset. Separate them and create the default_attrs using the
sysfs_create_files instead. By doing this we will have the
flexibility that device discovery thread could create fsid
kobject.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
We need it in a seperate function so that it can be called from the
device discovery thread as well.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
As of now the order in which the kobjects are created
at btrfs_sysfs_add_one() is..
fsid
features
unknown features (dynamic features)
devices.
Since we would move fsid and device kobject to fs_devices
from fs_info structure, this patch will reorder in which
the kobjects are created as below.
fsid
devices
features
unknown features (dynamic features)
And hence the btrfs_sysfs_remove_one() will follow the same
in reverse order. and the device kobject destroy now can
be moved into the function __btrfs_sysfs_remove_one()
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Since the failure code in the btrfs_sysfs_add_one() can
call btrfs_sysfs_remove_one() even before device_dir_kobj
has been created we need to check if its null.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
The sysfs clean up self test like in the below code fails, since
fs_info->device_dir_kobject still points to its stale kobject.
Reseting this pointer will help to fix this.
open_ctree()
{
ret = btrfs_sysfs_add_one(fs_info);
::
+ btrfs_sysfs_remove_one(fs_info);
+ ret = btrfs_sysfs_add_one(fs_info);
+ if (ret) {
+ pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
+ goto fail_block_groups;
+ }
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Theoritically need to remove the device links attributes, but since its entire device
kobject was removed, so there wasn't any issue of about it. Just do it nicely.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
The following test case fails indicating that, thread tried to init an initialized object.
kernel: [232104.016513] kobject (ffff880006c1c980): tried to init an initialized object, something is seriously wrong.
btrfs_sysfs_remove_one() self test code:
open_tree()
{
::
ret = btrfs_sysfs_add_one(fs_info);
if (ret) {
pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
goto fail_block_groups;
}
+ btrfs_sysfs_remove_one(fs_info);
+ ret = btrfs_sysfs_add_one(fs_info);
+ if (ret) {
+ pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
+ goto fail_block_groups;
+ }
cleaning up the unregistered kobject fixes this.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
There are some op tables that can be easily made const, similarly the
sysfs feature and raid tables. This is motivated by PaX CONSTIFY plugin.
Signed-off-by: David Sterba <dsterba@suse.cz>
BTRFS_ATTR_RW could set the mode and be inline with BTRFS_ATTR
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
All that uses BTRFS_ATTR want mode to be set at 0444 so just do
it at the define. And few spacing alignments.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit 49c6f736f34f901117c20960ebd7d5e60f12fcac(
btrfs: dev replace should replace the sysfs entry) added the missing sysfs entry
in the process of device replace, but didn't take missing devices into account,
so now we have
BUG: unable to handle kernel NULL pointer dereference at 0000000000000088
IP: [<ffffffffa0268551>] btrfs_kobj_rm_device+0x21/0x40 [btrfs]
...
To reproduce it,
1. mkfs.btrfs -f disk1 disk2
2. mkfs.ext4 disk1
3. mount disk2 /mnt -odegraded
4. btrfs replace start -B 1 disk3 /mnt
--------------------------
This fixes the problem.
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Tested-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
we would need the device links to be created,
when device is added.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
when we delete the device from the mounted btrfs,
we would need its corresponding sysfs enty to
be removed as well.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
We are currently allocating space_info objects in an array when we
allocate space_info. When a user does something like:
# btrfs balance start -mconvert=raid1 -dconvert=raid1 /mnt
# btrfs balance start -mconvert=single -dconvert=single /mnt -f
# btrfs balance start -mconvert=raid1 -dconvert=raid1 /
We can end up with memory corruption since the kobject hasn't
been reinitialized properly and the name pointer was left set.
The rationale behind allocating them statically was to avoid
creating a separate kobject container that just contained the
raid type. It used the index in the array to determine the index.
Ultimately, though, this wastes more memory than it saves in all
but the most complex scenarios and introduces kobject lifetime
questions.
This patch allocates the kobjects dynamically instead. Note that
we also remove the kobject_get/put of the parent kobject since
kobject_add and kobject_del do that internally.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
I have an opinion that system logs /var/log/messages are
valuable info to investigate the real system issues at
the data center. People handling data center issues
do spend a lot time and efforts analyzing messages
files. Having usage error logged into /var/log/messages
is something we should avoid.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Similar to the FS_INFO updates, export the basic filesystem info through
sysfs: node size, sector size and clone alignment.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Help during debugging to export various interesting infromation and
tunables without the need of extra mount options or ioctls.
Usage:
* declare your variable in sysfs.h, and include where you need it
* define the variable in sysfs.c and make it visible via
debugfs_create_TYPE
Depends on CONFIG_DEBUG_FS.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
