Commit Graph

37 Commits

Author SHA1 Message Date
Benjamin Marzinski
3e11e53041 GFS2: ignore unlock failures after withdraw
After gfs2 has withdrawn the filesystem, it may still have many locks not
in the unlocked state.  If it is using lock_dlm, it will failed trying
the unlocks since it has already unmounted the lock manager. Instead, it
should set the SDF_SKIP_DLM_UNLOCK flag on withdraw, to signal that
it can skip the lock_manager on unlocks, and failback to lock_nolock
style unlocking.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-03-24 08:28:48 -04:00
Bob Peterson
a097dc7e24 GFS2: Make rgrp reservations part of the gfs2_inode structure
Before this patch, multi-block reservation structures were allocated
from a special slab. This patch folds the structure into the gfs2_inode
structure. The disadvantage is that the gfs2_inode needs more memory,
even when a file is opened read-only. The advantages are: (a) we don't
need the special slab and the extra time it takes to allocate and
deallocate from it. (b) we no longer need to worry that the structure
exists for things like quota management. (c) This also allows us to
remove the calls to get_write_access and put_write_access since we
know the structure will exist.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-12-14 12:16:38 -06:00
Bob Peterson
b54e9a0b92 GFS2: Extract quota data from reservations structure (revert 5407e24)
This patch basically reverts the majority of patch 5407e24.
That patch eliminated the gfs2_qadata structure in favor of just
using the reservations structure. The problem with doing that is that
it increases the size of the reservations structure. That is not an
issue until it comes time to fold the reservations structure into the
inode in memory so we know it's always there. By separating out the
quota structure again, we aren't punishing the non-quota users by
making all the inodes bigger, requiring more slab space. This patch
creates a new slab area to allocate the quota stuff so it's managed
a little more sanely.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-11-24 08:38:44 -06:00
Joe Perches
cb94eb066e GFS2: Convert gfs2_lm_withdraw to use fs_err
vprintk use is not prefixed by a KERN_<LEVEL>,
so emit these messages at KERN_ERR level.

Using %pV can save some code and allow fs_err to
be used, so do it.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-03-07 09:39:18 +00:00
Joe Perches
8382e26b2c GFS2: Use fs_<level> more often
Convert a couple of uses of pr_<level> to fs_<level>
Add and use fs_emerg.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-03-07 09:32:31 +00:00
Joe Perches
d77d1b58aa GFS2: Use pr_<level> more consistently
Add pr_fmt, remove embedded "GFS2: " prefixes.
This now consistently emits lower case "gfs2: " for each message.

Other miscellanea around these changes:

o Add missing newlines
o Coalesce formats
o Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-03-07 09:30:51 +00:00
Fabian Frederick
fc554ed3d8 GFS2: global conversion to pr_foo()
-All printk(KERN_foo converted to pr_foo().
-Messages updated to fit in 80 columns.
-fs_macros converted as well.
-fs_printk removed.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-03-06 17:34:06 +00:00
Steven Whitehouse
26e43a15d4 GFS2: Move gfs2_icbit_munge into quota.c
This function is only called twice, and both callers are
quota related, so lets move this function into quota.c and
make it static.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2013-10-02 14:47:02 +01:00
Steven Whitehouse
fd95e81cb1 GFS2: Reinstate withdraw ack system
This patch reinstates the ack system which withdraw should be using. It
appears to have been accidentally forgotten when the lock module was
merged into GFS2, due to two different sysfs files having the same name.

Reported-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2013-02-13 12:21:40 +00:00
Steven Whitehouse
e8c92ed769 GFS2: Clean up log write code path
Prior to this patch, we have two ways of sending i/o to the log.
One of those is used when we need to allocate both the data
to be written itself and also a buffer head to submit it. This
is done via sb_getblk and friends. This is used mostly for writing
log headers.

The other method is used when writing blocks which have some
in-place counterpart. This is the case for all the metadata
blocks which are journalled, and when journaled data is in use,
for unescaped journalled data blocks.

This patch replaces both of those two methods, and about half
a dozen separate i/o submission points with a single i/o
submission function. We also go direct to bio rather than
using buffer heads, since this allows us to build i/o
requests of the maximum size for the block device in
question. It also reduces the memory required for flushing
the log, which can be very useful in low memory situations.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-04-24 16:44:34 +01:00
Bob Peterson
36f5580be1 GFS2: Use slab for block reservation memory
This patch changes block reservations so it uses slab storage.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-04-24 16:44:29 +01:00
Steven Whitehouse
75ca61c101 GFS2: Remove a __GFP_NOFAIL allocation
In order to ensure that we've got enough buffer heads for flushing
the journal, the orignal code used __GFP_NOFAIL when performing
this allocation. Here we dispense with that in favour of using a
mempool. This should improve efficiency in low memory conditions
since flushing the journal is a good way to get memory back, we
don't want to be spinning, waiting on memory allocations. The
buffers which are allocated via this mempool are fairly short lived,
so that we'll recycle them pretty quickly.

Although there are other memory allocations which occur during the
journal flush process, this is the one which can potentially require
the most memory, so the most important one to fix.

The amount of memory reserved is a fixed amount, and we should not need
to scale it when there are a greater number of filesystems in use.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-08 12:10:23 +00:00
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Steven Whitehouse
009d851837 GFS2: Metadata address space clean up
Since the start of GFS2, an "extra" inode has been used to store
the metadata belonging to each inode. The only reason for using
this inode was to have an extra address space, the other fields
were unused. This means that the memory usage was rather inefficient.

The reason for keeping each inode's metadata in a separate address
space is that when glocks are requested on remote nodes, we need to
be able to efficiently locate the data and metadata which relating
to that glock (inode) in order to sync or sync and invalidate it
(depending on the remotely requested lock mode).

This patch adds a new type of glock, which has in addition to
its normal fields, has an address space. This applies to all
inode and rgrp glocks (but to no other glock types which remain
as before). As a result, we no longer need to have the second
inode.

This results in three major improvements:
 1. A saving of approx 25% of memory used in caching inodes
 2. A removal of the circular dependency between inodes and glocks
 3. No confusion between "normal" and "metadata" inodes in super.c

Although the first of these is the more immediately apparent, the
second is just as important as it now enables a number of clean
ups at umount time. Those will be the subject of future patches.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2010-03-01 14:07:37 +00:00
Bob Peterson
d34843d0c4 GFS2: Add "-o errors=panic|withdraw" mount options
This patch adds "-o errors=panic" and "-o errors=withdraw" to the
gfs2 mount options.  The "errors=withdraw" option is today's
current behaviour, meaning to withdraw from the file system if a
non-serious gfs2 error occurs.  The new "errors=panic" option
tells gfs2 to force a kernel panic if a non-serious gfs2 file
system error occurs.  This may be useful, for example, where
fabric-level fencing is used that has no way to reboot (such as
fence_scsi).

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-08-24 10:44:18 +01:00
Steven Whitehouse
f057f6cdf6 GFS2: Merge lock_dlm module into GFS2
This is the big patch that I've been working on for some time
now. There are many reasons for wanting to make this change
such as:
 o Reducing overhead by eliminating duplicated fields between structures
 o Simplifcation of the code (reduces the code size by a fair bit)
 o The locking interface is now the DLM interface itself as proposed
   some time ago.
 o Fewer lookups of glocks when processing replies from the DLM
 o Fewer memory allocations/deallocations for each glock
 o Scope to do further optimisations in the future (but this patch is
   more than big enough for now!)

Please note that (a) this patch relates to the lock_dlm module and
not the DLM itself, that is still a separate module; and (b) that
we retain the ability to build GFS2 as a standalone single node
filesystem with out requiring the DLM.

This patch needs a lot of testing, hence my keeping it I restarted
my -git tree after the last merge window. That way, this has the maximum
exposure before its merged. This is (modulo a few minor bug fixes) the
same patch that I've been posting on and off the the last three months
and its passed a number of different tests so far.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-03-24 11:21:14 +00:00
Steven Whitehouse
37b2c8377c GFS2: Clean up & move gfs2_quotad
This patch is a clean up of gfs2_quotad prior to giving it an
extra job to do in addition to the current portfolio of updating
the quota and statfs information from time to time.

As a result it has been moved into quota.c allowing one of the
functions it calls to be made static. Also the clean up allows
the two existing functions to have separate timeouts and also
to coexist with its future role of dealing with the "truncate in
progress" inode flag.

The (pointless) setting of gfs2_quotad_secs is removed since we
arrange to only wake up quotad when one of the two timers expires.

In addition the struct gfs2_quota_data is moved into a slab cache,
mainly for easier debugging. It should also be possible to use
a shrinker in the future, rather than the current scheme of scanning
the quota data entries from time to time.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:05 +00:00
Steven Whitehouse
da755fdb41 [GFS2] Remove lm.[ch] and distribute content
The functions in lm.c were just wrappers which were mostly
only used in one other file. By moving the functions to
the files where they are being used, they can be marked
static and also this will usually result in them being inlined
since they are often only used from one point in the code.

A couple of really trivial functions have been inlined by hand
into the function which called them as it makes the code clearer
to do that.

We also gain from one fewer function call in the glock lock and
unlock paths.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-03-31 10:40:26 +01:00
Bob Peterson
6bdd9be628 [GFS2] Allocate gfs2_rgrpd from slab memory
This patch moves the gfs2_rgrpd structure to its own slab
memory.  This makes it easier to control and monitor, and
yields less memory fragmentation.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-03-31 10:40:07 +01:00
Steven Whitehouse
bb8d8a6f54 [GFS2] Fix sign problem in quota/statfs and cleanup _host structures
This patch fixes some sign issues which were accidentally introduced
into the quota & statfs code during the endianess annotation process.
Also included is a general clean up which moves all of the _host
structures out of gfs2_ondisk.h (where they should not have been to
start with) and into the places where they are actually used (often only
one place). Also those _host structures which are not required any more
are removed entirely (which is the eventual plan for all of them).

The conversion routines from ondisk.c are also moved into the places
where they are actually used, which for almost every one, was just one
single place, so all those are now static functions. This also cleans up
the end of gfs2_ondisk.h which no longer needs the #ifdef __KERNEL__.

The net result is a reduction of about 100 lines of code, many functions
now marked static plus the bug fixes as mentioned above. For good
measure I ran the code through sparse after making these changes to
check that there are no warnings generated.

This fixes Red Hat bz #239686

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-07-09 08:23:10 +01:00
Steven Whitehouse
dbb7cae2a3 [GFS2] Clean up inode number handling
This patch cleans up the inode number handling code. The main difference
is that instead of looking up the inodes using a struct gfs2_inum_host
we now use just the no_addr member of this structure. The tests relating
to no_formal_ino can then be done by the calling code. This has
advantages in that we want to do different things in different code
paths if the no_formal_ino doesn't match. In the NFS patch we want to
return -ESTALE, but in the ->lookup() path, its a bug in the fs if the
no_formal_ino doesn't match and thus we can withdraw in this case.

In order to later fix bz #201012, we need to be able to look up an inode
without knowing no_formal_ino, as the only information that is known to
us is the on-disk location of the inode in question.

This patch will also help us to fix bz #236099 at a later date by
cleaning up a lot of the code in that area.

There are no user visible changes as a result of this patch and there
are no changes to the on-disk format either.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-07-09 08:22:24 +01:00
Tim Schmielau
cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00
Christoph Lameter
e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
Fabio Massimo Di Nitto
7d308590ae [GFS2] Export lm_interface to kernel headers
lm_interface.h has a few out of the tree clients such as GFS1
and userland tools.

Right now, these clients keeps a copy of the file in their build tree
that can go out of sync.

Move lm_interface.h to include/linux, export it to userland and
clean up fs/gfs2 to use the new location.

Signed-off-by: Fabio M. Di Nitto <fabbione@ubuntu.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-19 08:45:18 -04:00
Steven Whitehouse
cd915493fc [GFS2] Change all types to uX style
This makes all fixed size types have consistent names.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-04 12:49:07 -04:00
Steven Whitehouse
e9fc2aa091 [GFS2] Update copyright, tidy up incore.h
As per comments from Jan Engelhardt <jengelh@linux01.gwdg.de> this
updates the copyright message to say "version" in full rather than
"v.2". Also incore.h has been updated to remove forward structure
declarations which are not required.

The gfs2_quota_lvb structure has now had endianess annotations added
to it. Also quota.c has been updated so that we now store the
lvb data locally in endian independant format to avoid needing
a structure in host endianess too. As a result the endianess
conversions are done as required at various points and thus the
conversion routines in lvb.[ch] are no longer required. I've
moved the one remaining constant in lvb.h thats used into lm.h
and removed the unused lvb.[ch].

I have not changed the HIF_ constants. That is left to a later patch
which I hope will unify the gh_flags and gh_iflags fields of the
struct gfs2_holder.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-01 11:05:15 -04:00
Steven Whitehouse
feaa7bba02 [GFS2] Fix unlinked file handling
This patch fixes the way we have been dealing with unlinked,
but still open files. It removes all limits (other than memory
for inodes, as per every other filesystem) on numbers of these
which we can support on GFS2. It also means that (like other
fs) its the responsibility of the last process to close the file
to deallocate the storage, rather than the person who did the
unlinking. Note that with GFS2, those two events might take place
on different nodes.

Also there are a number of other changes:

 o We use the Linux inode subsystem as it was intended to be
used, wrt allocating GFS2 inodes
 o The Linux inode cache is now the point which we use for
local enforcement of only holding one copy of the inode in
core at once (previous to this we used the glock layer).
 o We no longer use the unlinked "special" file. We just ignore it
completely. This makes unlinking more efficient.
 o We now use the 4th block allocation state. The previously unused
state is used to track unlinked but still open inodes.
 o gfs2_inoded is no longer needed
 o Several fields are now no longer needed (and removed) from the in
core struct gfs2_inode
 o Several fields are no longer needed (and removed) from the in core
superblock

There are a number of future possible optimisations and clean ups
which have been made possible by this patch.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-06-14 15:32:57 -04:00
Steven Whitehouse
382066da25 [GFS2] Casts for printing 64bit numbers
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-24 10:22:09 -04:00
Steven Whitehouse
3a8a9a1034 [GFS2] Update copyright date to 2006
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-18 15:09:15 -04:00
Steven Whitehouse
bd8968010a [GFS2] Remove semaphore.h from C files
We no longer use semaphores, everything has been converted to
mutex or rwsem, so we don't need to include this header any more.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-18 14:54:58 -04:00
Steven Whitehouse
1e09ae544e [GFS2] Move BUG() back into the header file
In order to make the file and line number reporting work
correctly, this has been moved back into the header file.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-21 15:52:46 -04:00
Steven Whitehouse
1dde2dbfc7 [GFS2] Add back missing BUG()
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-21 15:39:02 -04:00
Steven Whitehouse
71b86f562b [GFS2] Further updates to dir and logging code
This reduces the size of the directory code by about 3k and gets
readdir() to use the functions which were introduced in the previous
directory code update.

Two memory allocations are merged into one. Eliminates zeroing of some
buffers which were never used before they were initialised by
other data.

There is still scope for further improvement in the directory code.

On the logging side, a hand created mutex has been replaced by a
standard Linux mutex in the log allocation code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-03-28 14:14:04 -05:00
Steven Whitehouse
5c676f6d35 [GFS2] Macros removal in gfs2.h
As suggested by Pekka Enberg <penberg@cs.helsinki.fi>.

The DIV_RU macro is renamed DIV_ROUND_UP and and moved to kernel.h
The other macros are gone from gfs2.h as (although not requested
by Pekka Enberg) are a number of included header file which are now
included individually. The inode number comparison function is
now an inline function.

The DT2IF and IF2DT may be addressed in a future patch.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-27 17:23:27 -05:00
Steven Whitehouse
18ec7d5c3f [GFS2] Make journaled data files identical to normal files on disk
This is a very large patch, with a few still to be resolved issues
so you might want to check out the previous head of the tree since
this is known to be unstable. Fixes for the various bugs will be
forthcoming shortly.

This patch removes the special data format which has been used
up till now for journaled data files. Directories still retain the
old format so that they will remain on disk compatible with earlier
releases. As a result you can now do the following with journaled
data files:

 1) mmap them
 2) export them over NFS
 3) convert to/from normal files whenever you want to (the zero length
    restriction is gone)

In addition the level at which GFS' locking is done has changed for all
files (since they all now use the page cache) such that the locking is
done at the page cache level rather than the level of the fs operations.
This should mean that things like loopback mounts and other things which
touch the page cache directly should now work.

Current known issues:

 1. There is a lock mode inversion problem related to the resource
    group hold function which needs to be resolved.
 2. Any significant amount of I/O causes an oops with an offset of hex 320
    (NULL pointer dereference) which appears to be related to a journaled data
    buffer appearing on a list where it shouldn't be.
 3. Direct I/O writes are disabled for the time being (will reappear later)
 4. There is probably a deadlock between the page lock and GFS' locks under
    certain combinations of mmap and fs operation I/O.
 5. Issue relating to ref counting on internally used inodes causes a hang
    on umount (discovered before this patch, and not fixed by it)
 6. One part of the directory metadata is different from GFS1 and will need
    to be resolved before next release.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-08 11:50:51 +00:00
Steven Whitehouse
666a2c534c [GFS2] Remove unused code from various files
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-18 10:29:04 +00:00
David Teigland
b3b94faa5f [GFS2] The core of GFS2
This patch contains all the core files for GFS2.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-16 16:50:04 +00:00