gfs2: No longer use 'extern' in function declarations

For non-static function declarations, external linkage is implied and
the 'extern' keyword isn't needed. Some static checkers complain about
the overuse of 'extern', so clean up all the function declarations.

In addition, remove 'extern' from the definition of
free_local_statfs_inodes(); it isn't needed there, either.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

gfs2: Rename gfs2_lookup_{ simple => meta }

Function gfs2_lookup_simple() is used for looking up inodes in the
metadata directory tree, so rename it to gfs2_lookup_meta() to closer
match its purpose. Clean the function up a little on the way.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

gfs2: Convert gfs2_internal_read to folios

Change gfs2_internal_read() to use folios. Convert sizes to size_t.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

gfs2: Stop using GFS2_BASIC_BLOCK and GFS2_BASIC_BLOCK_SHIFT

Header gfs2_ondisk.h defines GFS2_BASIC_BLOCK and GFS2_BASIC_BLOCK_SHIFT
in a misguided attempt to abstract away the fact that sectors on block
devices are 512 or (1 << 9) bytes in size. Stop using those definitions.

I would be inclinded to remove those definitions altogether, but the
gfs2 user-space tools are using them.

In addition, instead of GFS2_SB(inode)->sd_sb.sb_bsize_shift, simply use
inode->i_blkbits.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Andrew Price <anprice@redhat.com>

fs: port ->permission() to pass mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

fs: port ->fileattr_set() to pass mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

gfs2: Convert to release_folio

Use a folio throughout gfs2_release_folio().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

gfs2: Make gfs2_setattr_simple static

This function is only used in inode.c.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

gfs2: convert to fileattr

Use the fileattr API to let the VFS handle locking, permission checking and
conversion.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>

fs: make helpers idmap mount aware

Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

gfs2: Make inode operations static

The inode operations are not used outside inode.c.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

gfs2: Minor gfs2_lookup_by_inum cleanup

Use a zero no_formal_ino instead of a NULL pointer to indicate that any inode
generation number will qualify: a valid inode never has a zero no_formal_ino.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 398

Based on 1 normalized pattern(s):

this copyrighted material is made available to anyone wishing to use
modify copy or redistribute it subject to the terms and conditions
of the gnu general public license version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 44 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081038.653000175@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gfs2: Fix an incorrect gfs2_assert()

When updating the inode information after a change in allocation,
convert the change into the same units as the inode's i_blocks count
before comparing it in an assertion.

Also, change the comparison so that it is still possible to set i_blocks
to zero by adding -i_blocks, something that was previously only possible
because of the difference in units.

Signed-off-by: Tim Smith <tim.smith@citrix.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

gfs2: Clean up gfs2_is_{ordered,writeback}

The gfs2_is_ordered and gfs2_is_writeback checks are weird in that they
implicitly check for !gfs2_is_jdata. This makes understanding how to
use those functions correctly a challenge. Clean this up by making
gfs2_is_ordered and gfs2_is_writeback take a super block instead of an
inode and by removing the implicit !gfs2_is_jdata checks. Update the
callers accordingly.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

gfs2: Implement SEEK_HOLE / SEEK_DATA via iomap

So far, lseek on gfs2 did not report holes.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

GFS2: use BIT() macro

Replace 1 << value shift by more explicit BIT() macro

Also fixes two bare unsigned definitions:

WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
+ unsigned hsize = BIT(ip->i_depth);

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

gfs2: Get rid of gfs2_ilookup

Now that gfs2_lookup_by_inum only takes the inode glock for new inodes
(and not for cached inodes anymore), there no longer is a need to
optimize the cached-inode case in gfs2_get_dentry or delete_work_func,
and gfs2_ilookup can be removed.

In addition, gfs2_get_dentry wasn't checking the GFS2_DIF_SYSTEM flag in
i_diskflags in the gfs2_ilookup case (see gfs2_lookup_by_inum); this
inconsistency goes away as well.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

gfs2: Fix gfs2_lookup_by_inum lock inversion

The current gfs2_lookup_by_inum takes the glock of a presumed inode
identified by block number, verifies that the block is indeed an inode,
and then instantiates and reads the new inode via gfs2_inode_lookup.

However, instantiating a new inode may block on freeing a previous
instance of that inode (__wait_on_freeing_inode), and freeing an inode
requires to take the glock already held, leading to lock inversion and
deadlock.

Fix this by first instantiating the new inode, then verifying that the
block is an inode (if required), and then reading in the new inode, all
in gfs2_inode_lookup.

If the block we are looking for is not an inode, we discard the new
inode via iget_failed, which marks inodes as bad and unhashes them.
Other tasks waiting on that inode will get back a bad inode back from
ilookup or iget_locked; in that case, retry the lookup.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

GFS2: Eliminate parameter non_block on gfs2_inode_lookup

Now that we're not filtering out I_FREEING inodes from our lookups
anymore, we can eliminate the non_block parameter from the lookup
function.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2: Don't filter out I_FREEING inodes anymore

This patch basically reverts a very old patch from 2008,
7a9f53b3c1875bef22ad4588e818bc046ef183da, with the title
"Alternate gfs2_iget to avoid looking up inodes being freed".
The original patch was designed to avoid a deadlock caused by lock
ordering with try_rgrp_unlink. The patch forced the function to not
find inodes that were being removed by VFS. The problem is, that
made it impossible for nodes to delete their own unlinked dinodes
after a certain point in time, because the inode needed was not found
by this filtering process. There is no longer a need for the patch,
since function try_rgrp_unlink no longer locks the inode: All it does
is queue the glock onto the delete work_queue, so there should be no
more deadlock.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2: Add atomic_open support

I've restricted atomic_open to only operate on regular files, although
I still don't understand why atomic_open should not be possible also for
directories on GFS2. That can always be added in later though, if it
makes sense.

The ->atomic_open function can be passed negative dentries, which
in most cases means either ENOENT (->lookup) or a call to d_instantiate
(->create). In the GFS2 case though, we need to actually perform the
look up, since we do not know whether there has been a new inode created
on another node. The look up calls d_splice_alias which then tries to
rehash the dentry - so the solution here is to simply check for that
in d_splice_alias. The same issue is likely to affect any other cluster
filesystem implementing ->atomic_open

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields fieldses org>
Cc: Jeff Layton <jlayton@redhat.com>

GFS2: Remove unused argument from gfs2_internal_read

gfs2_internal_read accepts an unused ra_state argument, left over from
when we did readahead on the rindex. Since there are currently no plans
to add back this readahead, this patch removes the ra_state parameter
and updates the functions which call gfs2_internal_read accordingly.

Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2: make function gfs2_page_add_databufs static

This patch makes function gfs2_page_add_databufs static.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2: Use ->dirty_inode()

The aim of this patch is to use the newly enhanced ->dirty_inode()
super block operation to deal with atime updates, rather than
piggy backing that code into ->write_inode() as is currently
done.

The net result is a simplification of the code in various places
and a reduction of the number of gfs2_dinode_out() calls since
this is now implied by ->dirty_inode().

Some of the mark_inode_dirty() calls have been moved under glocks
in order to take advantage of then being able to avoid locking in
->dirty_inode() when we already have suitable locks.

One consequence is that generic_write_end() now correctly deals
with file size updates, so that we do not need a separate check
for that afterwards. This also, indirectly, means that fdatasync
should work correctly on GFS2 - the current code always syncs the
metadata whether it needs to or not.

Has survived testing with postmark (with and without atime) and
also fsx.

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

->permission() sanitizing: don't pass flags to ->permission()

not used by the instances anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

GFS2: Clean up symlink creation

This moves the symlink specific parts of inode creation
into the function where we initialise the rest of the
dinode. As a result we have one less place where we need
to look up the inode's buffer.

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

GFS2: Remove gfs2_dinode_print() function

This function was intended for debugging purposes, but it is not very
useful. If we want to know what is on disk then all we need is a
block number and gfs2_edit can give us much better information about
what is there. Otherwise, if we are interested in what is stored in
the in-core inode, it doesn't help us out there either.

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

GFS2: When adding a new dir entry, inc link count if it is a subdir

This adds an increment of the link count when we add a new directory
entry, if that entry is itself a directory. This means that we no
longer need separate code to perform this operation.

Now that both adding and removing directory entries automatically
update the parent directory's link count if required, that makes
the code shorter and simpler than before.

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

GFS2: Make writeback more responsive to system conditions

This patch adds writeback_control to writing back the AIL
list. This means that we can then take advantage of the
information we get in ->write_inode() in order to set off
some pre-emptive writeback.

In addition, the AIL code is cleaned up a bit to make it
a bit simpler to understand.

There is still more which can usefully be done in this area,
but this is a good start at least.

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

GFS2: Optimise glock lru and end of life inodes

The GLF_LRU flag introduced in the previous patch can be
used to check if a glock is on the lru list when a new
holder is queued and if so remove it, without having first
to get the lru_lock.

The main purpose of this patch however is to optimise the
glocks left over when an inode at end of life is being
evicted. Previously such glocks were left with the GLF_LFLUSH
flag set, so that when reclaimed, each one required a log flush.
This patch resets the GLF_LFLUSH flag when there is nothing
left to flush thus preventing later log flushes as glocks are
reused or demoted.

In order to do this, we need to keep track of the number of
revokes which are outstanding, and also to clear the GLF_LFLUSH
bit after a log commit when only revokes have been processed.

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

GFS2: filesystem hang caused by incorrect lock order

This patch fixes a deadlock in GFS2 where two processes are trying
to reclaim an unlinked dinode:
One holds the inode glock and calls gfs2_lookup_by_inum trying to look
up the inode, which it can't, due to I_FREEING. The other has set
I_FREEING from vfs and is at the beginning of gfs2_delete_inode
waiting for the glock, which is held by the first. The solution is to
add a new non_block parameter to the gfs2_iget function that causes it
to return -ENOENT if the inode is being freed.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2: Fix error path in gfs2_lookup_by_inum()

In the (impossible, except if there is fs corruption) error path
in gfs2_lookup_by_inum() if the call to gfs2_inode_refresh()
fails, it was leaving the function by calling iput() rather
than iget_failed(). This would cause future lookups of the same
inode to block forever.

This patch fixes the problem by moving the call to gfs2_inode_refresh()
into gfs2_inode_lookup() where iget_failed() is part of the error path
already. Also this cleans up some unreachable code and makes
gfs2_set_iop() static.

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

fs: provide rcu-walk aware permission i_ops

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

GFS2: Fix inode deallocation race

This area of the code has always been a bit delicate due to the
subtleties of lock ordering. The problem is that for "normal"
alloc/dealloc, we always grab the inode locks first and the rgrp lock
later.

In order to ensure no races in looking up the unlinked, but still
allocated inodes, we need to hold the rgrp lock when we do the lookup,
which means that we can't take the inode glock.

The solution is to borrow the technique already used by NFS to solve
what is essentially the same problem (given an inode number, look up
the inode carefully, checking that it really is in the expected
state).

We cannot do that directly from the allocation code (lock ordering
again) so we give the job to the pre-existing delete workqueue and
carry on with the allocation as normal.

If we find there is no space, we do a journal flush (required anyway
if space from a deallocation is to be released) which should block
against the pending deallocations, so we should always get the space
back.

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

GFS2: fallocate support

This patch adds support for fallocate to gfs2. Since the gfs2 does not support
uninitialized data blocks, it must write out zeros to all the blocks. However,
since it does not need to lock any pages to read from, gfs2 can write out the
zero blocks much more efficiently. On a moderately full filesystem, fallocate
works around 5 times faster on average. The fallocate call also allows gfs2 to
add blocks to the file without changing the filesize, which will make it
possible for gfs2 to preallocate space for the rindex file, so that gfs2 can
grow a completely full filesystem.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2: Remove i_disksize

With the update of the truncate code, ip->i_disksize and
inode->i_size are merely copies of each other. This means
we can remove ip->i_disksize and use inode->i_size exclusively
reducing the size of a GFS2 inode by 8 bytes.

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

GFS2: Rework reclaiming unlinked dinodes

The previous patch I wrote for reclaiming unlinked dinodes
had some shortcomings and did not prevent all hangs.
This version is much cleaner and more logical, and has
passed very difficult testing. Sorry for the churn.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2: glock livelock

This patch fixes a couple gfs2 problems with the reclaiming of
unlinked dinodes. First, there were a couple of livelocks where
everything would come to a halt waiting for a glock that was
seemingly held by a process that no longer existed. In fact, the
process did exist, it just had the wrong pid number in the holder
information. Second, there was a lock ordering problem between
inode locking and glock locking. Third, glock/inode contention
could sometimes cause inodes to be improperly marked invalid by
iget_failed.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>

GFS2: Move gfs2_unlink_ok into ops_inode.c

Another function which is only called from one ops_inode.c so
we move it and make it static.

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

GFS2: Move gfs2_readlinki into ops_inode.c

Move gfs2_readlinki into ops_inode.c and make it static

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

GFS2: Move gfs2_rmdiri into ops_inode.c

Move gfs2_rmdiri() into ops_inode.c and make it static.

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

GFS2: Clean up some file names

This patch renames the ops_*.c files which have no counterpart
without the ops_ prefix in order to shorten the name and make
it more readable. In addition, ops_address.h (which was very
small) is moved into inode.h and inode.h is cleaned up by
adding extern where required.

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

GFS2: cleanup file_operations mess

Remove the weird pointer to file_operations mess and replace it with
straight-forward defining of the lockinginstance names to the _nolock
variants.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

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>

GFS2: Banish struct gfs2_dinode_host

The final field in gfs2_dinode_host was the i_flags field. Thats
renamed to i_diskflags in order to avoid confusion with the existing
inode flags, and moved into the inode proper at a suitable location
to avoid creating a "hole".

At that point struct gfs2_dinode_host is no longer needed and as
promised (quite some time ago!) it can now be removed completely.

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

GFS2: Rationalise header files

Move the contents of some headers which contained very
little into more sensible places, and remove the original
header files. This should make it easier to find things.

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

GFS2: high time to take some time over atime

Until now, we've used the same scheme as GFS1 for atime. This has failed
since atime is a per vfsmnt flag, not a per fs flag and as such the
"noatime" flag was not getting passed down to the filesystems. This
patch removes all the "special casing" around atime updates and we
simply use the VFS's atime code.

The net result is that GFS2 will now support all the same atime related
mount options of any other filesystem on a per-vfsmnt basis. We do lose
the "lazy atime" updates, but we gain "relatime". We could add lazy
atime to the VFS at a later date, if there is a requirement for that
variant still - I suspect relatime will be enough.

Also we lose about 100 lines of code after this patch has been applied,
and I have a suspicion that it will speed things up a bit, even when
atime is "on". So it seems like a nice clean up as well.

From a user perspective, everything stays the same except the loss of
the per-fs atime quantum tweekable (ought to be per-vfsmnt at the very
least, and to be honest I don't think anybody ever used it) and that a
number of options which were ignored before now work correctly.

Please let me know if you've got any comments. I'm pushing this out
early so that you can all see what my plans are.

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

GFS2: Fix & clean up GFS2 rename

This patch fixes a locking issue in the rename code by ensuring that we hold
the per sb rename lock over both directory and "other" renames which involve
different parent directories.

At the same time, this moved the (only called from one place) function
gfs2_ok_to_move into the file that its called from, so we can mark it
static. This should make a code a bit easier to follow.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Peter Staubach <staubach@redhat.com>

[PATCH] don't pass nameidata to gfs2_lookupi()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

[GFS2] Remove unused declaration

The implementation of gfs2_inode_attr_in is removed.
So remove its declaration.

Signed-off-by: Li Xiaodong <lixd@cn.fujitsu.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] don't call permission()

GFS2 calls permission() to verify permissions after locks on the files
have been taken.

For this it's sufficient to call gfs2_permission() instead. This
results in the following changes:

- IS_RDONLY() check is not performed
- IS_IMMUTABLE() check is not performed
- devcgroup_inode_permission() is not called
- security_inode_permission() is not called

IS_RDONLY() should be unnecessary anyway, as the per-mount read-only
flag should provide protection against read-only remounts during
operations. do_gfs2_set_flags() has been fixed to perform
mnt_want_write()/mnt_drop_write() to protect against remounting
read-only.

IS_IMMUTABLE has been added to gfs2_permission()

Repeating the security checks seems to be pointless, as they don't
normally change, and if they do, it's independent of the filesystem
state.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] Eliminate (almost) duplicate field from gfs2_inode

The blocks counter is almost a duplicate of the i_blocks
field in the VFS inode. The only difference is that i_blocks
can be only 32bits long for 32bit arch without large single file
support. Since GFS2 doesn't handle the non-large single file
case (for 32 bit anyway) this adds a new config dependency on
64BIT || LSF. This has always been the case, however we've never
explicitly said so before.

Even if we do add support for the non-LSF case, we will still
not require this field to be duplicated since we will not be
able to access oversized files anyway.

So the net result of all this is that we shave 8 bytes from a gfs2_inode
and get our config deps correct.

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

[GFS2] Streamline indirect pointer tree height calculation

This patch improves the calculation of the tree height in order to reduce
the number of operations which are carried out on each call to gfs2_block_map.
In the common case, we now make a single comparison, rather than calculating
the required tree height from scratch each time. Also in the case that the
tree does need some extra height, we start from the current height rather from
zero when we work out what the new height ought to be.

In addition the di_height field is moved into the inode proper and reduced
in size to a u8 since the value must be between 0 and GFS2_MAX_META_HEIGHT (10).

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

[GFS2] Introduce gfs2_set_aops()

Just like ext3 we now have three sets of address space operations
to cover the cases of writeback, ordered and journalled data
writes. This means that the individual operations can now become
less complicated as we are able to remove some of the tests for
file data mode from the code.

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

[GFS2] Add gfs2_is_writeback()

This adds a function "gfs2_is_writeback()" along the lines of the
existing "gfs2_is_jdata()" in order to clean up the code and make
the various tests for the inode mode more obvious. It also fixes
the PageChecked() logic where we were resetting the flag too early
in the case of an error path.

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

[GFS2] Alternate gfs2_iget to avoid looking up inodes being freed

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: Benjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] Remove i_mode passing from NFS File Handle

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: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] Obtaining no_formal_ino from directory entry

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: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[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>

[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>

[GFS2] make gfs2_change_nlink_i() static

On Thu, Jan 11, 2007 at 10:26:27PM -0800, Andrew Morton wrote:
>...
> Changes since 2.6.20-rc3-mm1:
>...
> git-gfs2-nmw.patch
>...
> git trees
>...

This patch makes the needlessly globlal gfs2_change_nlink_i() static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] Fix gfs2_rename deadlock

Second round of gfs2_rename lock re-ordering to allow Anaconda adding
root partition on top of gfs2. Previous to this patch the recursive
lock detector in glock.c can be triggered due to attempting to lock
the rgrp twice. This fixes it by checking to see whether the rgrp
is already locked.

This fixes Red Hat bugzilla #221237

Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] Fix change nlink deadlock

Bugzilla 215088

Fix deadlock in gfs2_change_nlink() while installing RHEL5 into GFS2
partition. The gfs2_rename() apparently needs block allocation for the
new name (into the directory) where it requires rg locks. At the same
time, while updating the nlink count for the replaced file,
gfs2_change_nlink() tries to return the inode meta-data back to resource
group where it needs rg locks too. Our logic doesn't allow process to
acquire these locks recursively by the same process (RHEL installer)
that results a BUG call. This only happens within rename code path and
only if the destination file exists before the rename operation.

Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] Remove unused function from inode.c

The gfs2_glock_nq_m_atime function is unused in so far as its only
ever called with num_gh = 1, and this falls through to the
gfs2_glock_nq_atime function, so we might as well call that directly.

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

[GFS2] Remove gfs2_inode_attr_in

This function wasn't really doing the right thing. There was no need
to update the inode size at this point and the updating of the
i_blocks field has now been moved to the places where di_blocks is
updated. A result of this patch and some those preceeding it is that
unlocking a glock is now a much more efficient process, since there
is no longer any requirement to copy data from the gfs2 inode into
the vfs inode at this point.

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

[GFS2] Shrink gfs2_inode (6) - di_atime/di_mtime/di_ctime

Remove the di_[amc]time fields and use inode->i_[amc]time
fields instead. This saves 24 bytes from the gfs2_inode.

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

[GFS2] Shrink gfs2_inode (3) - di_mode

This removes the duplicate di_mode field in favour of using the
inode->i_mode field. This saves 4 bytes.

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

[GFS2] Shrink gfs2_inode (2) - di_major/di_minor

This removes the device numbers from this structure by using
inode->i_rdev instead. It also cleans up the code in gfs2_mknod.
It results in shrinking the gfs2_inode by 8 bytes.

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

[GFS2] split and annotate gfs2_inum

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

[GFS2/DLM] Fix trailing whitespace

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

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

[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>

[GFS2] Remove gfs2_repermission

gfs2_repermission is just a wrapper for permission, so remove it and
call permission directly where required.

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

[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>

[GFS2] Update copyright date to 2006

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

[GFS2] Reordering in deallocation to avoid recursive locking

Despite my earlier careful search, there was a recursive lock left
in the deallocation code. This removes it. It also should speed up
deallocation be reducing the number of locking operations which take
place by using two "try lock" operations on the two locks involved in
inode deallocation which allows us to grab the locks out of order
(compared with NFS which grabs the inode lock first and the iopen
lock later). It is ok for us to fail while doing this since if it
does fail it means that someone else is still using the inode and
thus it wouldn't be possible to deallocate anyway.

This fixes the bug reported to me by Rob Kenna.

Cc: Rob Kenna <rkenna@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

[GFS2] Fix bug in directory code and tidy up

Due to a typo, the dir leaf split operation was (for the first
split in a directory) writing the new hash vaules at the
wrong offset. This is now fixed.

Also some other tidy ups are included:

- We use GFS2's hash function for dentries (see ops_dentry.c) so that
we don't have to keep recalculating the hash values.
- A lot of common code is eliminated between the various directory
lookup routines.
- Better error checking on directory lookup (previously different
routines checked for different errors)
- The leaf split operation has a couple of redundant operations
removed from it, so it should be faster.

There is still further scope for further clean ups in the directory
code, and readdir in particular could do with slimming down a bit.

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

[GFS2] Tidy up mount code.

We no longer lookup ".gfs2_admin" in the root directory in order to
find it, but instead use the inode number given in the superblock.
Both the root directory and the admin directory are now looked up using
the same routine, so the redundant code is removed.

Also, there is no longer a reference to the root inode in the
GFS2 super block. When required this can be retreived via
sb->s_root->d_inode instead.

Assuming that we introduce a metadata filesystem type for GFS, then
this is a first step towards that goal.

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

[GFS2] 80 Column audit of GFS2

Requested by:
Prarit Bhargava <prarit@redhat.com>

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

[GFS2] Fix for root inode ref count bug

Umount is now working correctly again. The bug was due to
not getting an extra ref count when mounting the fs. We
should have bumped it by two (once for the internal pointer
to the root inode from the super block and once for the
inode hanging off the dcache entry for root).

Also this patch tidys up the code dealing with looking up
and creating inodes. We now pass Linux inodes (with gfs2_inodes
attached) rather than the other way around and this reduces code
duplication in various places.

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

[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>

[GFS2] Add gfs2_internal_read()

Add the new external read function. Its temporarily in jdata.c
even though the protoype is in ops_file.h - this will change
shortly. The current implementation will change to a page cache
one when that happens.

In order to effect the above changes, the various internal inodes
now have Linux inodes attached to them. We keep the references to
the Linux inodes, rather than the gfs2_inodes in the super block.

In order to get everything to work correctly I've had to reorder
the init sequence on mount (which I should probably have done
earlier when .gfs2_admin was made visible).

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

[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>