linux.git/include/linux/gfs2_ondisk.h, branch master

UAPI: (Scripted) Disintegrate include/linux

2012-10-13T09:46:48+00:00

Signed-off-by: David Howells 
Acked-by: Arnd Bergmann 
Acked-by: Thomas Gleixner 
Acked-by: Michael Kerrisk 
Acked-by: Paul E. McKenney 
Acked-by: Dave Jones

GFS2: Use lvbs for storing rgrp information with mount option

2012-06-08T10:50:01+00:00

Instead of reading in the resource groups when gfs2 is checking
for free space to allocate from, gfs2 can store the necessary infromation
in the resource group's lvb.  Also, instead of searching for unlinked
inodes in every resource group that's checked for free space, gfs2 can
store the number of unlinked but inodes in the lvb, and only check for
unlinked inodes if it will find some.

The first time a resource group is locked, the lvb must initialized.
Since this involves counting the unlinked inodes in the resource group,
this takes a little extra time.  But after that, if the resource group
is locked with GL_SKIP, the buffer head won't be read in unless it's
actually needed.

Enabling the resource groups lvbs is done via the rgrplvb mount option.  If
this option isn't set, the lvbs will still be set and updated, but they won't
be verfied or used by the filesystem.  To safely turn on this option, all of
the nodes mounting the filesystem must be running code with this patch, and
the filesystem must have been completely unmounted since they were updated.

Signed-off-by: Benjamin Marzinski 
Signed-off-by: Steven Whitehouse

GFS2: Add "top dir" flag support

2012-06-06T10:27:36+00:00

This patch adds support for the "top dir" flag. Currently this is unused
but a subsequent patch is planned which will add support for the
Orlov allocation policy when allocating subdirectories in a parent
with this flag set.

In order to ensure backward compatible behaviour, mkfs.gfs2 does
not currently tag the root directory with this flag, it must always be
set manually.

Signed-off-by: Steven Whitehouse

GFS2: FITRIM ioctl support

2012-02-28T17:10:21+00:00

The FITRIM ioctl provides an alternative way to send discard requests to
the underlying device. Using the discard mount option results in every
freed block generating a discard request to the block device. This can
be slow, since many block devices can only process discard requests of
larger sizes, and also such operations can be time consuming.

Rather than using the discard mount option, FITRIM allows a sweep of the
filesystem on an occasional basis, and also to optionally avoid sending
down discard requests for smaller regions.

In GFS2 FITRIM will work at resource group granularity. There is a flag
for each resource group which keeps track of which resource groups have
been trimmed. This flag is reset whenever a deallocation occurs in the
resource group, and set whenever a successful FITRIM of that resource
group has taken place. This helps to reduce repeated discard requests
for the same block ranges, again improving performance.

Signed-off-by: Steven Whitehouse

GFS2: dlm based recovery coordination

2012-01-11T09:23:05+00:00

This new method of managing recovery is an alternative to
the previous approach of using the userland gfs_controld.

- use dlm slot numbers to assign journal id's
- use dlm recovery callbacks to initiate journal recovery
- use a dlm lock to determine the first node to mount fs
- use a dlm lock to track journals that need recovery

Signed-off-by: David Teigland 
Signed-off-by: Steven Whitehouse

GFS2: Remove old, unused linked list code from quota

2010-03-01T14:08:10+00:00

This is the kernel portion of the patch-set for upstream gfs2,
to remove the quota-linked-list stuff and replace it with
fiemap-based traversal of the quota file.

The corresponding userland fixes have been pushed to
STABLE3 and master branches of cluster.git and gfs2-utils.git
respectively (Refer Red Hat bug #536902).

Signed-off-by: Abhi Das 
Signed-off-by: Steven Whitehouse

GFS2: Tag all metadata with jid

2009-12-03T11:58:47+00:00

There are two spare field in the header common to all GFS2
metadata. One is just the right size to fit a journal id
in it, and this patch updates the journal code so that each
time a metadata block is modified, we tag it with the journal
id of the node which is performing the modification.

The reason for this is that it should make it much easier to
debug issues which arise if we can tell which node was the
last to modify a particular metadata block.

Since the field is updated before the block is written into
the journal, each journal should only contain metadata which
is tagged with its own journal id. The one exception to this
is the journal header block, which might have a different node's
id in it, if that journal was recovered by another node in the
cluster.

Thus each journal will contain a record of which nodes recovered
it, via the journal header.

The other field in the metadata header could potentially be
used to hold information about what kind of operation was
performed, but for the time being we just zero it on each
transaction so that if we use it for that in future, we'll
know that the information (where it exists) is reliable.

I did consider using the other field to hold the journal
sequence number, however since in GFS2's journaling we write
the modified data into the journal and not the original
data, this gives no information as to what action caused the
modification, so I think we can probably come up with a better
use for those 64 bits in the future.

Signed-off-by: Steven Whitehouse

GFS2: Add explanation of extended attr on-disk format

2009-08-25T12:44:04+00:00

Some useful info regarding the on-disk representation of
GFS2 extended attributes.

Signed-off-by: Steven Whitehouse

headers_check fix: linux/gfs2_ondisk.h

2009-01-30T18:20:12+00:00

fix the following 'make headers_check' warning:

  usr/include/linux/gfs2_ondisk.h:109: found __[us]{8,16,32,64} type without #include 

Signed-off-by: Jaswinder Singh Rajput

GFS2: Add UUID to GFS2 sb

2008-09-22T06:29:31+00:00

This patch adds a UUID to the GFS2 sb structure. This field is not
actually referenced from kernel space at all, but is added for
completeness and due to the userland tools which get their on-disk
structure information from the gfs2_ondisk.h header file.

Since we have to be backwards compatible, we will assume that any GFS2
sb for which the UUID is all 0 does not have a UUID as such.

We should then be (after some userland changes) able to support the -U
mount option. This addresses Fedora bugzilla #242689

Signed-off-by: Steven Whitehouse