Commit Graph

18 Commits

Author SHA1 Message Date
Sage Weil
ce769a2904 Btrfs: use __u64 types in ioctl.h
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-16 14:24:27 -04:00
Josef Bacik
1406e4327b Btrfs: add a "df" ioctl for btrfs
df is a very loaded question in btrfs.  This gives us a way to get the per-space
usage information so we can tell exactly what is in use where.  This will help
us figure out ENOSPC problems, and help users better understand where their disk
space is going.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15 11:00:14 -04:00
Chris Mason
1e701a3292 Btrfs: add new defrag-range ioctl.
The btrfs defrag ioctl was limited to doing the entire file.  This
commit adds a new interface that can defrag a specific range inside
the file.

It can also force compression on the file, allowing you to selectively
compress individual files after they were created, even when mount -o
compress isn't turned on.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15 11:00:10 -04:00
Josef Bacik
6ef5ed0d38 Btrfs: add ioctl and incompat flag to set the default mount subvol
This patch needs to go along with my previous patch.  This lets us set the
default dir item's location to whatever root we want to use as our default
mounting subvol.  With this we don't have to use mount -o subvol=<tree id>
anymore to mount a different subvol, we can just set the new one and it will
just magically work.  I've done some moderate testing with this, mostly just
switching the default mount around, mounting subvols and the default mount at
the same time and such, everything seems to work.  Thanks,

Older kernels would generally be able to still mount the filesystem with the
default subvolume set, but it would result in a different volume being mounted,
which could be an even more unpleasant suprise for users.  So if you set your
default subvolume, you can't go back to older kernels.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15 11:00:08 -04:00
Chris Mason
ac8e9819d7 Btrfs: add search and inode lookup ioctls
The search ioctl is a generic tool for doing btree searches from
userland applications.  The first user of the search ioctl is a
subvolume listing feature, but we'll also use it to find new
files in a subvolume.

The search ioctl allows you to specify min and max keys to search for,
along with min and max transid.  It returns the items along with a
header that includes the item key.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15 10:55:10 -04:00
Yan, Zheng
76dda93c6a Btrfs: add snapshot/subvolume destroy ioctl
This patch adds snapshot/subvolume destroy ioctl.  A subvolume that isn't being
used and doesn't contains links to other subvolumes can be destroyed.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 16:00:26 -04:00
Chris Mason
c071fcfdb6 Btrfs: fix ioctl arg size (userland incompatible change!)
The structure used to send device in btrfs ioctl calls was not
properly aligned, and so 32 bit ioctls would not work properly on
64 bit kernels.

We could fix this with compat ioctls, but we're just one byte away
and it doesn't make sense at this stage to carry about the compat ioctls
forever at this stage in the project.

This patch brings the ioctl arg up to an evenly aligned 4k.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-01-16 11:59:08 -05:00
Chris Mason
3de4586c52 Btrfs: Allow subvolumes and snapshots anywhere in the directory tree
Before, all snapshots and subvolumes lived in a single flat directory.  This
was awkward and confusing because the single flat directory was only writable
with the ioctls.

This commit changes the ioctls to create subvols and snapshots at any
point in the directory tree.  This requires making separate ioctls for
snapshot and subvol creation instead of a combining them into one.

The subvol ioctl does:

btrfsctl -S subvol_name parent_dir

After the ioctl is done subvol_name lives inside parent_dir.

The snapshot ioctl does:

btrfsctl -s path_for_snapshot root_to_snapshot

path_for_snapshot can be an absolute or relative path.  btrfsctl breaks it up
into directory and basename components.

root_to_snapshot can be any file or directory in the FS.  The snapshot
is taken of the entire root where that file lives.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-11-17 21:02:50 -05:00
Sage Weil
c5c9cd4d1b Btrfs: allow clone of an arbitrary file range
This patch adds an additional CLONE_RANGE ioctl to clone an arbitrary 
(block-aligned) file range to another file.  The original CLONE ioctl 
becomes a special case of cloning the entire file range.  The logic is a 
bit more complex now since ranges may be cloned to different offsets, and 
because we may only be cloning the beginning or end of a particular extent 
or checksum item.

An additional sanity check ensures the source and destination files aren't 
the same (which would previously deadlock), although eventually this could 
be extended to allow the duplication of file data at a different offset 
within the same file.

Any extents within the destination range in the target file are dropped.

We currently do not cope with the case where a compressed inline extent 
needs to be split.  This will probably require decompressing the extent 
into a temporary address_space, and inserting just the cloned portion as a 
new compressed inline extent.  For now, just return -EINVAL in this case.  
Note that this never comes up in the more common case of cloning an entire 
file.
    
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-11-12 14:32:25 -05:00
Sage Weil
6bf13c0cc8 Btrfs: transaction ioctls
These ioctls let a user application hold a transaction open while it
performs a series of operations.  A final ioctl does a sync on the fs
(closing the current transaction).  This is the main requirement for
Ceph's OSD to be able to keep the data it's storing in a btrfs volume
consistent, and AFAICS it works just fine.  The application would do
something like

	fd = ::open("some/file", O_RDONLY);
	::ioctl(fd, BTRFS_IOC_TRANS_START);
	/* do a bunch of stuff */
	::ioctl(fd, BTRFS_IOC_TRANS_END);
or just
	::close(fd);

And to ensure it commits to disk,

	::ioctl(fd, BTRFS_IOC_SYNC);

When a transaction is held open, the trans_handle is attached to the
struct file (via private_data) so that it will get cleaned up if the
process dies unexpectedly.  A held transaction is also ended on fsync() to
avoid a deadlock.

A misbehaving application could also deliberately hold a transaction open,
effectively locking up the FS, so it may make sense to restrict something
like this to root or something.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:03 -04:00
Sage Weil
f2eb0a241f Btrfs: Clone file data ioctl
Add a new ioctl to clone file data

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:02 -04:00
Chris Mason
788f20eb5a Btrfs: Add new ioctl to add devices
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:02 -04:00
Chris Mason
8a4b83cc8b Btrfs: Add support for device scanning and detection ioctls
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:01 -04:00
Chris Mason
edbd8d4efe Btrfs: Support for online FS resize (grow and shrink)
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:03:58 -04:00
Chris Mason
6702ed490c Btrfs: Add run time btree defrag, and an ioctl to force btree defrag
This adds two types of btree defrag, a run time form that tries to
defrag recently allocated blocks in the btree when they are still in ram,
and an ioctl that forces defrag of all btree blocks.

File data blocks are not defragged yet, but this can make a huge difference
in sequential btree reads.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-08-07 16:15:09 -04:00
Chris Mason
6cbd557078 Btrfs: add GPLv2
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-06-12 09:07:21 -04:00
Chris Mason
8352d8a473 Btrfs: add disk ioctl, mostly working
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-12 10:43:05 -04:00
Chris Mason
c5739bba52 Btrfs: snapshot progress
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2007-04-10 09:27:04 -04:00