As requested by Christoph, this patch cleans up GFS2's internal
read function so that it no longer uses the do_generic_mapping_read
function. This function is obsolete and GFS2 is the last user of it.

As a side effect the internal read code gets smaller and easier
to read and gfs2_readpage is split into two. One function has the locking
and the other function has the rest of the logic.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>

There is a possible deadlock between two processes on the same node, where one
process is deleting an inode, and another process is looking for allocated but
unused inodes to delete in order to create more space.

process A does an iput() on inode X, and it's i_count drops to 0. This causes
iput_final() to be called, which puts an inode into state I_FREEING at
generic_delete_inode(). There no point between when iput_final() is called, and
when I_FREEING is set where GFS2 could acquire any glocks. Once I_FREEING is
set, no other process on that node can successfully look up that inode until
the delete finishes.

process B locks the the resource group for the same inode in get_local_rgrp(),
which is called by gfs2_inplace_reserve_i()

process A tries to lock the resource group for the inode in
gfs2_dinode_dealloc(), but it's already locked by process B

process B waits in find_inode for the inode to have the I_FREEING state cleared.

Deadlock.

This patch solves the problem by adding an alternative to gfs2_iget(),
gfs2_iget_skip(), that simply skips any inodes that are in the I_FREEING
state.o The alternate test function is just like the original one, except that
it fails if the inode is being freed, and sets a skipped flag. The alternate
set function is just like the original, except that it fails if the skipped
flag is set. Only try_rgrp_unlink() calls gfs2_iget_skip() instead of
gfs2_iget().
Signed-off-by: NBenjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This is for bugzilla bug #248176: GFS2: invalid metadata block

Patches 1 thru 3 were accepted upstream, but there were problems
with 4 and 5.  Those issues have been resolved and now the recovery
tests are passing without errors.  This code has gone through
41 * 3 successful gfs2 recovery tests before it hit an
unrelated (openais) problem.

This is a complete rewrite of patch 4 for bug #248176.

Part of the problem was that inodes were being recycled
before their buffers were flushed to the journal logs.
Another problem was that the clone bitmaps were being
searched for deleted inodes to recycle, but only the
"real" bitmaps should be searched for that purpose.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This is patch three of five for bug #248176.

The try_rgrp_unlink code in rgrp.c had an infinite loop.  This was
caused because the bitmap function rgblk_search can return a block
less than the "goal" block, in which case it was looping.  The fix is
to make it always march forward as needed.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The following patch fixes a bug where 0 was being used as a return code
to indicate "nothing to do" when in fact 0 was a valid block location
which might be returned by the function.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch seems to fix the problem described in bugzilla bug 246114.
It was written by Steve Whitehouse with some tweaking by me.

The code was looping in the relatively new section of code designed to
search for and reuse unlinked inodes.  In cases where it was finding an
appropriate inode to reuse, it was looping around and finding the same
block over and over because a "<=" check should have been a "<" when
comparing the goal block to the last unlinked block found.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

GFS2 has been passing i_mode within NFS File Handle. Other than the
wrong assumption that there is always room for this extra 16 bit value,
the current gfs2_get_dentry doesn't really need the i_mode to work
correctly. Note that GFS2 NFS code does go thru the same lookup code
path as direct file access route (where the mode is obtained from name
lookup) but gfs2_get_dentry() is coded for different purpose. It is not
used during lookup time. It is part of the file access procedure call.
When the call is invoked, if on-disk inode is not in-memory, it has to
be read-in. This makes i_mode passing a useless overhead.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

GFS2 lookup code doesn't ask for inode shared glock. This implies during
in-memory inode creation for existing file, GFS2 will not disk-read in
the inode contents. This leaves no_formal_ino un-initialized during
lookup time. The un-initialized no_formal_ino is subsequently encoded
into file handle. Clients will get ESTALE error whenever it tries to
access these files.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Not sure how it slipped in, but we don't want it anyway.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Under certain circumstances its possible (though rather unlikely) that
inodes which were unlinked by one node while still open on another might
get "lost" in the sense that they don't get deallocated if the node
which held the inode open crashed before it was unlinked.

This patch adds the recovery code which allows automatic deallocation of
the inode if its found during block allocation (the sensible time to
look for such inodes since we are scanning the rgrp's bitmaps anyway at
this time, so it adds no overhead to do this).

Since the inode will have had its i_nlink set to zero, all we need to
trigger recovery is a lookup and an iput(), and the normal deallocation
code takes care of the rest.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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: NSteven Whitehouse <swhiteho@redhat.com>

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: NSteven Whitehouse <swhiteho@redhat.com>

This addendum patch 2 corrects three things:

1. It fixes a stupid mistake in the previous addendum that broke gfs2.
   Ref: https://www.redhat.com/archives/cluster-devel/2007-May/msg00162.html
2. It fixes a problem that Dave Teigland pointed out regarding the
   external declarations in ops_address.h being in the wrong place.
3. It recasts a couple more %llu printks to (unsigned long long)
   as requested by Steve Whitehouse.

I would have loved to put this all in one revised patch, but there was
a rush to get some patches for RHEL5.	Therefore, the previous patches
were applied to the git tree "as is" and therefore, I'm posting another
addendum.  Sorry.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

To avoid code redundancy, I separated out the operational "guts" into
a new function called read_rindex_entry.  Then I made two functions:
the closer-to-original gfs2_ri_update (without the special condition
checks) and gfs2_ri_update_special that's designed with that condition
in mind.  (I don't like the name, but if you have a suggestion, I'm
all ears).

Oh, and there's an added benefit:  we don't need all the ugly gotos
anymore.  ;)

This patch has been tested with gfs2_fsck_hellfire (which runs for
three and a half hours, btw).
Signed-off-By: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This is another revision of my gfs2 kernel patch that allows
gfs2_grow to function properly.

Steve Whitehouse expressed some concerns about the previous
patch and I restructured it based on his comments.
The previous patch was doing the statfs_change at file close time,
under its own transaction.  The current patch does the statfs_change
inside the gfs2_commit_write function, which keeps it under the
umbrella of the inode transaction.

I can't call ri_update to re-read the rindex file during the
transaction because the transaction may have outstanding unwritten
buffers attached to the rgrps that would be otherwise blown away.
So instead, I created a new function, gfs2_ri_total, that will
re-read the rindex file just to total the file system space
for the sake of the statfs_change.  The ri_update will happen
later, when gfs2 realizes the version number has changed, as it
happened before my patch.

Since the statfs_change is happening at write_commit time and there
may be multiple writes to the rindex file for one grow operation.
So one consequence of this restructuring is that instead of getting
one kernel message to indicate the change, you may see several.
For example, before when you did a gfs2_grow, you'd get a single
message like:

GFS2: File system extended by 247876 blocks (968MB)

Now you get something like:

GFS2: File system extended by 207896 blocks (812MB)
GFS2: File system extended by 39980 blocks (156MB)

This version has also been successfully run against the hours-long
"gfs2_fsck_hellfire" test that does several gfs2_grow and gfs2_fsck
while interjecting file system damage.  It does this repeatedly
under a variety Resource Group conditions.
Signed-off-By: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Ths following patch makes GFS2 use the rgrp flags properly. Although
there are also separate flags for both data and metadata as well, I've
not implemented these as there seems little use for them. On the
otherhand, the "noalloc" flag is generally useful for future changes we
might which to make, so this ensures that we interpret it correctly.

In addition I fixed the comment above the function which was incorrect.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This is a fix for bz #208514. When GFS2 frees up space, the freed blocks
aren't available for reuse until the resource group is successfully written
to the ondisk journal. So in rare cases, GFS2 operations will fail, saying
that the filesystem is out of space, when in reality, you are just waiting for
a log flush. For instance, on a 1Gig filesystem, if I continually write 10 Mb
to a file, and then truncate it, after a hundred interations, the write will
fail with -ENOSPC, even though the filesystem is just 1% full.

The attached patch calls a log flush in these cases.  I tested this patch
fairly heavily to check if there were any locking issues that I missed, and
it seems to work just fine. Also, this patch only does the log flush if
get_local_rgrp makes a complete loop of resource groups without skipping
any do to locking issues. The code would be slightly simpler if it just always
did the log flush after the first failed pass, and you could only ever have
to go through the loop twice, instead of up to three times. However, I guessed
that failing to find a rg simply do to locking issues would be common enough
to skip the log flush in that case, but I'm not certain that this is the right
way to go. Either way, I don't suppose this code will be hit all that often.
Signed-off-by: NBenjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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: NTim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove duplicate di_uid/di_gid fields in favour of using
inode->i_uid/inode->i_gid instead. This saves 8 bytes.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

As per Andrew Morton's request, removed trailing whitespace.

Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Fix a bug in the directory reading code, where we might have dereferenced
a NULL pointer in case of OOM. Updated the directory code to use the new
& improved version of gfs2_meta_ra() which now returns the first block
that was being read. Previously it was releasing it requiring following
code to grab the block again at each point it was called.

Also turned off readahead on directory lookups since we are reading a
hash table, and therefore reading the entries in order is very
unlikely. Readahead is still used for all other calls to the
directory reading function (e.g. when growing the hash table).

Removed the DIO_START constant. Everywhere this was used, it was
used to unconditionally start i/o aside from a couple of places, so
I've removed it and made the couple of exceptions to this rule into
separate functions.

Also hunted through the other DIO flags and removed them as arguments
from functions which were always called with the same combination of
arguments.

Updated gfs2_meta_indirect_buffer to be a bit more efficient and
hopefully also be a bit easier to read.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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: NFabio M. Di Nitto <fabbione@ubuntu.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

As per Jan Engelhardt's follow up emails, here are a few small
fixes which were missed earlier.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Change one constant plus remove a redundant !!.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This makes all fixed size types have consistent names.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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: NSteven Whitehouse <swhiteho@redhat.com>

Another case where list_del should be list_del_init.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Some allocations in rgrp.c should have been GFP_NOFS
rather than GFP_KERNEL.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This adds a generation number for the eventual use of NFS to the
ondisk inode. Its backward compatible with the current code since
it doesn't really matter what the generation number is to start with,
and indeed since its set to zero, due to it being taken from padding
in both the inode and rgrp header, it should be fine.

The eventual plan is to use this rather than no_formal_ino in the
NFS filehandles. At that point no_formal_ino will be unused.

At the same time we also add a releasepages call back to the
"normal" address space for gfs2 inodes. Also I've removed a
one-linrer function thats not required any more.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch makes the following needlessly global code static:
- eaops.c: struct gfs2_security_eaops
- rgrp.c: gfs2_free_uninit_di()
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

A few of my printks slipped through last time. Also fix a couple of
minor bugs.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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: NSteven Whitehouse <swhiteho@redhat.com>

Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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: NSteven Whitehouse <swhiteho@redhat.com>

The functions moved from bits.c can now be made static.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Since they are small and will be inlined by the complier,
it makes sense to merge the contents of bits.[ch] into
rgrp.c
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This adds readpages support (and also corrects a small bug in
the readpage error path at the same time). Hopefully this will
improve performance by allowing GFS to submit larger lumps of
I/O at a time.

In order to simplify the setting of BH_Boundary, it currently gets
set when we hit the end of a indirect pointer block. There is
always a boundary at this point with the current allocation code.
It doesn't get all the boundaries right though, so there is still
room for improvement in this.

See comments in fs/gfs2/ops_address.c for further information about
readpages with GFS2.

Signed-off-by: Steven Whitehouse

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: NSteven Whitehouse <swhiteho@redhat.com>