Two of the bug traps here could really be warnings. The others are
converted from BUG() to GLOCK_BUG_ON() since we'll most likely
need to know the glock state in order to debug any issues which
arise. As a result of this, __dump_glock has to be renamed and
is no longer static.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

In gfs2_trans_add_bh(), gfs2 was testing if a there was a bd attached to the
buffer without having the gfs2_log_lock held. It was then assuming it would
stay attached for the rest of the function. However, without either the log
lock being held of the buffer locked, __gfs2_ail_flush() could detach bd at any
time.  This patch moves the locking before the test.  If there isn't a bd
already attached, gfs2 can safely allocate one and attach it before locking.
There is no way that the newly allocated bd could be on the ail list,
and thus no way for __gfs2_ail_flush() to detach it.
Signed-off-by: NBenjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

file_accessed() was being called by gfs2_mmap() with a shared glock. If it
needed to update the atime, it was crashing because it dirtied the inode in
gfs2_dirty_inode() without holding an exclusive lock. gfs2_dirty_inode()
checked if the caller was already holding a glock, but it didn't make sure that
the glock was in the exclusive state. Now, instead of calling file_accessed()
while holding the shared lock in gfs2_mmap(), file_accessed() is called after
grabbing and releasing the glock to update the inode.  If file_accessed() needs
to update the atime, it will grab an exclusive lock in gfs2_dirty_inode().

gfs2_dirty_inode() now also checks to make sure that if the calling process has
already locked the glock, it has an exclusive lock.
Signed-off-by: NBenjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Currently implementation in gfs2 uses FITRIM arguments as it were in
file system blocks units which is wrong. The FITRIM arguments
(fstrim_range.start, fstrim_range.len and fstrim_range.minlen) are
actually in bytes.

Moreover, check for start argument beyond the end of file system, len
argument being smaller than file system block and minlen argument being
bigger than biggest resource group were missing.

This commit converts the code to convert FITRIM argument to file system
blocks and also adds appropriate checks mentioned above.

All the problems were recognised by xfstests 251 and 260.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When the fstrim_range argument is not provided by user in FITRIM ioctl
we should just return EFAULT and not promoting bad behaviour by filling
the structure in kernel. Let the user deal with it.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Cleans up two cases where variables were assigned values but then never
used again.
Signed-off-by: NAndrew Price <anprice@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Despite the return value from kmem_cache_zalloc() being checked, the
error wasn't being returned until after a possible null pointer
dereference. This patch returns the error immediately, allowing the
removal of the error variable.
Signed-off-by: NAndrew Price <anprice@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Check the return value of gfs2_rs_alloc(ip) and avoid a possible null
pointer dereference.
Signed-off-by: NAndrew Price <anprice@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
	u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
 [<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
 [<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
 [<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
 [<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.
Reported-by: NSasha Levin <levinsasha928@gmail.com>
Signed-off-by: NHugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Move actual pte filling for non-linear file mappings into the new special
vma operation: ->remap_pages().

Filesystems must implement this method to get non-linear mapping support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.

Now device drivers can implement this method and obtain nonlinear vma support.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>	#arch/tile
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If a dirty GFS2 inode was being deleted but was in use by another node, its
metadata was not getting written out before GFS2 checked for dirty buffers in
gfs2_ail_flush().  GFS2 was relying on inode_go_sync() to write out the
metadata when the other node tried to free the file, but it failed the error
check before it got that far. This patch writes out the metadata before calling
gfs2_ail_flush()
Signed-off-by: NBenjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

gfs2_ail_empty_gl() contains an "inline version" of gfs2_trans_begin(),
so it needs an explicit sb_start_intwrite() as well, to balance the
sb_end_intwrite() which will be called by gfs2_trans_end().

With this, xfstest 068 passes on lock_nolock local gfs2.
Without it, we reach a writer count of -1 and get stuck.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch fixes an infinite loop in gfs2_rbm_find that was introduced
by the previous patch. The problem occurred when the length was less
than 3 but the rbm block was byte-aligned, causing it to improperly
return a extent length of zero, which caused it to spin.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Tested-by: NBob Peterson <rpeterso@redhat.com>
Tested-by: NBarry Marson <bmarson@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>

GFS2 uses i_mutex on its system quota inode to synchronize writes to
quota file. Since this is an internal inode to GFS2 (not part of directory
hiearchy or visible by user) we are safe to define locking rules for it. So
let's just get it its own locking class to make it clear.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch stops multiple block allocations if a nonzero
return code is received from gfs2_rbm_from_block. Without
this patch, if enough pressure is put on the file system,
you get a kernel warning quickly followed by:
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffffa04f47e8>] gfs2_alloc_blocks+0x2c8/0x880 [gfs2]
With this patch, things run normally.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When rgd->rd_free_clone is less than rgd->rd_reserved, the
unclaimed_blocks() calculation would wrap and produce
incorrect results. This patch checks for this condition
when this function is called from gfs2_mblk_search()

In addition, the use of this particular function in other
places in the code has been dropped by means of a general
clean up of gfs2_inplace_reserve(). This function is now
much easier to follow.

Also the setting of the rgd->rd_last_alloc field is corrected.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch improves the tracing of block reservations by
removing some corner cases and also providing more useful
detail in the traces.

A new field is added to the reservation structure to contain
the inode number. This is used since in certain contexts it is
not possible to access the inode itself to obtain this information.
As a result we can then display the inode number for all tracepoints
and also in case we dump the resource group.

The "del" tracepoint operation has been removed. This could be called
with the reservation rgrp set to NULL. That resulted in not printing
the device number, and thus making the information largely useless
anyway. Also, the conditional on the rgrp being NULL can then be
removed from the tracepoint. After this change, all the block
reservation tracepoint calls will be called with the rgrp information.

The existing ins,clm and tdel calls to the block reservation tracepoint
are sufficient to track the entire life of the block reservation.

In gfs2_block_alloc() the error detection is updated to print out
the inode number of the problematic inode. This can then be compared
against the information in the glock dump,tracepoints, etc.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When we get to the stage of allocating blocks, we know that the
resource group in question must contain enough free blocks, otherwise
gfs2_inplace_reserve() would have failed. So if we are left with only
free blocks which are reserved, then we must use those. This can happen
if another node has sneeked in and use some blocks reserved on this
node, for example. Generally this will happen very rarely and only
when the resouce group is nearly full.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The ->show_options() function for GFS2 was not correctly displaying
the value when statfs slow in in use.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Reported-by: NMilos Jakubicek <xjakub@fi.muni.cz>

Use the rbm structure for gfs2_setbit() in order to simplify the
arguments to the function. We have to add a bool to control whether
the clone bitmap should be updated (if it exists) but otherwise it
is a more or less direct substitution.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Change the arguments to gfs2_testbit() so that it now just takes an
rbm specifying the position of the two bit entry to return.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Function gfs2_bitfit was checking for state > 3, but that's
impossible since it is only called from rgblk_search, which receives
only GFS2_BLKST_ constants.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Function add_to_queue was checking may_grant for the passed-in
holder for every iteration of its gh2 loop. Now it only checks it
once at the beginning to see if a try lock is futile.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Function gfs2_glock_dq_wait called two-line function wait_on_demote,
so they were combined.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Function gfs2_glock_wait only called function wait_on_holder and
returned its return code, so they were combined for readability.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Since function gfs2_glock_schedule_for_reclaim is only two
significant lines, we can eliminate it, simplifying the code
and making it more readable.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch changes function gfs2_direct_IO so that it uses a normal
call to gfs2_glock_dq rather than a call to a multiple-dq of one item.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch fixes a few small rbm related things. First, it fixes
a corner case where the rbm needs to switch bitmaps and wasn't
adjusting its buffer pointer. Second, there's a white space issue
fixed. Third, the logic in function gfs2_rbm_from_block was optimized
a bit. Lastly, a check for goal block overflows was added to function
gfs2_alloc_blocks.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

One corner case which the original patch failed to take into
account was when there is a reservation which ended such that
the following block was one beyond the end of the rgrp in
question. This extra test fixes that case.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Reported-by: NBob Peterson <rpeterso@redhat.com>
Tested-by: NBob Peterson <rpeterso@redhat.com>

gfs2 calls RB_EMPTY_NODE() to check if nodes are not on an rbtree.
The corresponding initialization function is RB_CLEAR_NODE().
rb_init_node() was never clearly defined and is going away.
Signed-off-by: NMichel Lespinasse <walken@google.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Replace open coded version with a call to gfs2_rbm_from_block()
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Use the new gfs2_rbm_from_block() function to replace an open
coded version of the same code.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This is part of a series of patches which are introducing the
gfs2_rbm structure throughout the block allocation code. The
main aim of this part is to create a search function which can
deal directly with struct gfs2_rbm. In this case it specifies
the initial position at which to start the search and also the
point at which the search terminates.

The net result of this is to clean up the search code and make
it rather more readable, and the various possible exceptions which
may occur during the search are partitioned into their own functions.

There are some bug fixes too. We should not be checking the reservations
while allocating extents - the time for that is when we are searching
for where to put the extent, not when we've already made that decision.

Also, rgblk_search had two uses, and in only one of those cases did
it make sense to check for reservations. This is fixed in the new
gfs2_rbm_find function, which has a cleaner interface.

The reservation checking has been improved by always checking for
contiguous reservations, and returning the first free block after
all contiguous reservations. This is done under the spin lock to
ensure consistancy of the tree.

The allocation of extents is now in all cases done by the existing
allocation code, and if there is an active reservation, that is updated
after the fact. Again this is done under the spin lock, since it entails
changing the lookup key for the reservation in question.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch introduces a new structure, gfs2_rbm, which is a
tuple of a resource group, a bitmap within the resource group
and an offset within that bitmap. This is designed to make
manipulating these sets of variables easier. There is also a
new helper function which converts this representation back
to a disk block address.

In addition, the rbtree nodes which are used for the reservations
were not being correctly initialised, which is now fixed. Also,
the tracing was not passing through the inode where it should
have been. That is mostly fixed aside from one corner case. This
needs to be revisited since there can also be a NULL rgrp in
some cases which results in the device being incorrect in the
trace.

This is intended to be the first step towards cleaning up some
of the allocation code, and some further bug fixes.
Signed-off-by: NSteven Whitehouse <swhiteho@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>

There were two functions in the xattr code which were nearly
identical, the only difference being that one was copy data into
the unstuffed xattrs and the other was copying data out from it.

This patch merges the two functions such that the code which deal
with iteration over the unstuffed xattrs is no longer duplicated.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Modify quota_send_warning to take struct kqid instead a type and
identifier pair.

When sending netlink broadcasts always convert uids and quota
identifiers into the intial user namespace.  There is as yet no way to
send a netlink broadcast message with different contents to receivers
in different namespaces, so for the time being just map all of the
identifiers into the initial user namespace which preserves the
current behavior.

Change the callers of quota_send_warning in gfs2, xfs and dquot
to generate a struct kqid to pass to quota send warning.  When
all of the user namespaces convesions are complete a struct kqid
values will be availbe without need for conversion, but a conversion
is needed now to avoid needing to convert everything at once.

Cc: Ben Myers <bpm@sgi.com>
Cc: Alex Elder <elder@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Update the quotactl user space interface to successfull compile with
user namespaces support enabled and to hand off quota identifiers to
lower layers of the kernel in struct kqid instead of type and qid
pairs.

The quota on function is not converted because while it takes a quota
type and an id.  The id is the on disk quota format to use, which
is something completely different.

The signature of two struct quotactl_ops methods were changed to take
struct kqid argumetns get_dqblk and set_dqblk.

The dquot, xfs, and ocfs2 implementations of get_dqblk and set_dqblk
are minimally changed so that the code continues to work with
the change in parameter type.

This is the first in a series of changes to always store quota
identifiers in the kernel in struct kqid and only use raw type and qid
values when interacting with on disk structures or userspace.  Always
using struct kqid internally makes it hard to miss places that need
conversion to or from the kernel internal values.

Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: Alex Elder <elder@kernel.org>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

 - Pass the user namespace the uid and gid values in the xattr are stored
   in into posix_acl_from_xattr.

 - Pass the user namespace kuid and kgid values should be converted into
   when storing uid and gid values in an xattr in posix_acl_to_xattr.

- Modify all callers of posix_acl_from_xattr and posix_acl_to_xattr to
  pass in &init_user_ns.

In the short term this change is not strictly needed but it makes the
code clearer.  In the longer term this change is necessary to be able to
mount filesystems outside of the initial user namespace that natively
store posix acls in the linux xattr format.

Cc: Theodore Tso <tytso@mit.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>