This patch cleans up the inode creation code path in GFS2. After the
Orlov allocator was merged, a number of potential improvements are
now possible, and this is a first set of these.

The quota handling is now updated so that it matches the point in
the code where the allocation takes place. This means that the one
exception in gfs2_alloc_blocks relating to quota is now no longer
required, and we can use the generic code everywhere.

In addition the call to figure out whether we need to allocate any
extra blocks in order to add a directory entry is moved higher up
gfs2_create_inode. This means that if it returns an error, we
can deal with that at a stage where it is easier to handle that case.
The returned status cannot change during the function since we hold
an exclusive lock on the directory.

Two calls to gfs2_rindex_update have been changed to one, again at
the top of gfs2_create_inode to simplify error handling.

The time stamps are also now initialised earlier in the creation
process, this is gradually moving towards being able to remove the
call to gfs2_refresh_inode in gfs2_inode_create once we have all the
fields covered.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When reading dinodes from the disk convert uids and gids
into kuids and kgids to store in vfs data structures.

When writing to dinodes to the disk convert kuids and kgids
in the in memory structures into plain uids and gids.

For now all on disk data structures are assumed to be
stored in the initial user namespace.

Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Where kuid_t values are compared use uid_eq and where kgid_t values
are compared use gid_eq.  This is unfortunately necessary because
of the type safety that keeps someone from accidentally mixing
kuids and kgids with other types.

Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Split NO_QUOTA_CHANGE into NO_UID_QUTOA_CHANGE and NO_GID_QUTOA_CHANGE
so the constants may be well typed.

Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

There is little common content in gfs2_trans_add_bh() between the data
and meta classes by the time that the functions which it calls are
taken into account. The intent here is to split this into two
separate functions. Stage one is to introduce gfs2_trans_add_data()
and gfs2_trans_add_meta() and update the callers accordingly.

Later patches will then pull in the content of gfs2_trans_add_bh()
and its dependent functions in order to clean up the code in this
area.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch fixes a cluster coherency problem that occurs when one
node creates a file, does several writes, then a different node
tries to write to the same file. When the inode's glock is demoted,
the inode wasn't synced to the media properly because the gl_object
wasn't set. Later, the flush daemon noticed the uncommitted data
and tried to flush it, only to discover the glock was no longer locked
properly in exclusive mode. That caused an assert withdraw.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch adds a return code check after attempting to allocate
a new inode during dinode creation.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Since we now have a dirty_inode that takes care of manipulating the
inode buffer and writing from the inode to the buffer, we can
eliminate some unnecessary buffer manipulations in gfs2_unlink_inode
that are now redundant.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Just like ext3, this works on the root directory and any directory
with the +T flag set. Also, just like ext3, any subdirectory created
in one of the just mentioned cases will be allocated to a random
resource group (GFS2 equivalent of a block group).

If you are creating a set of directories, each of which will contain a
job running on a different node, then by setting +T on the parent
directory before creating the subdirectories, each will land up in a
different resource group, and thus resource group contention between
nodes will be kept to a minimum.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Rather than using the parent directory's allocation context, this
patch allocated the new inode earlier in the process and then uses
it to contain all the information required. As a result, we can now
use the new inode's own allocation context to allocate it rather
than having to use the parent directory's context. This give us a
lot more flexibility in where the inode is placed on disk.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

With the recently added block reservation code, an additional function
was added to search for free blocks. This had a restriction of only being
able to search for aligned extents of free blocks. As a result the
allocation patterns when reserving blocks were suboptimal when the
existing allocation of blocks for an inode was not aligned to the same
boundary.

This patch resolves that problem by adding the ability for gfs2_rbm_find
to search for extents of a particular minimum size. We can then use
gfs2_rbm_find for both looking for reservations, and also looking for
free blocks on an individual basis when we actually come to do the
allocation later on. As a result we only need a single set of code
to deal with both situations.

The function gfs2_rbm_from_block() is moved up rgrp.c so that it
occurs before all of its callers.

Many thanks are due to Bob for helping track down the final issue in
this patch. That fix to the rb_tree traversal and to not share
block reservations from a dirctory to its children is included here.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Signed-off-by: NBob Peterson <rpeterso@redhat.com>

The rs_requested field is left over from the original allocation
code, however this should have been a parameter passed to the
various functions from gfs2_inplace_reserve() and not a member of the
reservation structure as the value is not required after the
initial allocation.

This also helps simplify the code since we no longer need to set
the rs_requested to zero. Also the gfs2_inplace_release()
function can also be simplified since the reservation structure
will always be defined when it is called, and the only remaining
task is to unlock the rgrp if required. It can also now be
called unconditionally too, resulting in a further simplification.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

These entry points were missed in the original patch to allocate
this data structure.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch reduces GFS2 file fragmentation by pre-reserving blocks. The
resulting improved on disk layout greatly speeds up operations in cases
which would have resulted in interlaced allocation of blocks previously.
A typical example of this is 10 parallel dd processes, each writing to a
file in a common dirctory.

The implementation uses an rbtree of reservations attached to each
resource group (and each inode).
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This patch moves the ancillary quota data structures into the
block reservations structure. This saves GFS2 some time and
effort in allocating and deallocating the qadata structure.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch lengthens the lifespan of the reservations structure for
inodes. Before, they were allocated and deallocated for every write
operation. With this patch, they are allocated when the first write
occurs, and deallocated when the last process closes the file.
It's more efficient to do it this way because it saves GFS2 a lot of
unnecessary allocates and frees. It also gives us more flexibility
for the future: (1) we can now fold the qadata structure back into
the structure and save those alloc/frees, (2) we can use this for
multi-block reservations.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch removes the call from gfs2_blk2rgrd to function
gfs2_rindex_update and replaces it with individual calls.
The former way turned out to be too problematic.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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

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

In GFS2 FITRIM will work at resource group granularity. There is a flag
for each resource group which keeps track of which resource groups have
been trimmed. This flag is reset whenever a deallocation occurs in the
resource group, and set whenever a successful FITRIM of that resource
group has taken place. This helps to reduce repeated discard requests
for the same block ranges, again improving performance.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This makes mount take slightly longer, but at the same time, the first
write to the filesystem will be faster too. It also means that if there
is a problem in the resource index, then we can refuse to mount rather
than having to try and report that when the first write occurs.

In addition, to avoid recursive locking, we hvae to take account of
instances when the rindex glock may already be held when we are
trying to update the rbtree of resource groups.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch fixes a problem whereby you were unable to delete
files until other file system operations were done (such as
statfs, touch, writes, etc.) that caused the rindex to be
read in.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Since the nlink count will be 0, we need to use set_nlink rather
than inc_nlink in order to avoid triggering the inc_nlink warning
which was added recently.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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

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

vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Quiets the sparse noise:

warning: symbol 'gfs2_initxattrs' was not declared. Should it be static?
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Clean up gfs2_alloc_blocks so that it takes the full extent length
rather than just the number of non-inode blocks as an argument. That
will only make a difference in the inode allocation case for now.

Also, this fixes the extent length handling around gfs2_alloc_extent() so
that multi block allocations will work again.

The rd_last_alloc block is set to the final block in the allocated
extent (as per the update to i_goal, but referenced to a different
start point).

This also removes the dinode argument to rgblk_search() which is no
longer used.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch separates the code pertaining to allocations into two
parts: quota-related information and block reservations.
This patch also moves all the block reservation structure allocations to
function gfs2_inplace_reserve to simplify the code, and moves
the frees to function gfs2_inplace_release.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch is a revision of the one I previously posted.
I tried to integrate all the suggestions Steve gave.
The purpose of the patch is to change function gfs2_alloc_block
(allocate either a dinode block or an extent of data blocks)
to a more generic gfs2_alloc_blocks function that can
allocate both a dinode _and_ an extent of data blocks in the
same call. This will ultimately help us create a multi-block
reservation scheme to reduce file fragmentation.

This patch moves more toward a generic multi-block allocator that
takes a pointer to the number of data blocks to allocate, plus whether
or not to allocate a dinode. In theory, it could be called to allocate
(1) a single dinode block, (2) a group of one or more data blocks, or
(3) a dinode plus several data blocks.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

GFS2 functions gfs2_alloc_block and gfs2_alloc_di do basically
the same things, with a few exceptions. This patch combines
the two functions into a slightly more generic gfs2_alloc_block.
Having one centralized block allocation function will reduce
code redundancy and make it easier to implement multi-block
reservations to reduce file fragmentation in the future.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

A potentially uninitialised variable, some unreachable code,
and the main part of this, fixing the error path in the
unlink function.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This means that after the initial allocation for any inode, the
last used resource group is cached in the inode for future use.
This drastically reduces the number of lookups of resource
groups in the common case, and this the contention on that
data structure.

The allocation algorithm is the same as previously, except that we
always check to see if the goal block is within the cached rgrp
first before going to the rbtree to look one up.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Since we have ruled out supporting online filesystem shrink,
it is possible to make the resource group list append only
during the life of a super block. This gives several benefits:

Firstly, we only need to read new rindex elements as they are added
rather than needing to reread the whole rindex file each time one
element is added.

Secondly, the rindex glock can be held for much shorter periods of
time, and is completely removed from the fast path for allocations.
The lock is taken in shared mode only when updating the resource
groups when the first allocation occurs, and after a grow has
taken place.

Thirdly, this results in a reduction in code size, and everything
gets a lot simpler to understand in this area.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

If we pass through knowledge of whether the creation is intended to be
exclusive or not, then we can deal with that in gfs2_create_inode
and remove one set of locking. Also this removes the loop in
gfs2_create and simplifies the code a bit.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

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: NSteven Whitehouse <swhiteho@redhat.com>

If we have got far enough through the inode allocation code
path that an inode has already been allocated, then we must
call iput to dispose of it, if an error occurs during a
later part of the process. This will always be the final iput
since there will be no other references to the inode.

Unlike when the inode has been unlinked, its block state will
be GFS2_BLKST_INODE rather than GFS2_BLKST_UNLINKED so we need
to skip the test in ->evict_inode() for this one case in order
to ensure that it will be deallocated correctly. This patch adds
a new flag in order to ensure that this will happen correctly.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Replace the ->check_acl method with a ->get_acl method that simply reads an
ACL from disk after having a cache miss.  This means we can replace the ACL
checking boilerplate code with a single implementation in namei.c.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>