We are seeing a bug when booting w/ iommu=pt with current upstream
(bisect blames 19943b0e "intel-iommu:
Unify hardware and software passthrough support).

The issue is specific to this loop during identity map initialization
of each device:

domain_context_mapping_one(si_domain, ..., CONTEXT_TT_PASS_THROUGH)
...
		/* Skip top levels of page tables for
		* iommu which has less agaw than default.
		*/
		for (agaw = domain->agaw; agaw != iommu->agaw; agaw--) {
			pgd = phys_to_virt(dma_pte_addr(pgd));
			if (!dma_pte_present(pgd)) {      <------ failing here
				spin_unlock_irqrestore(&iommu->lock, flags);
			return -ENOMEM;
		}

This box has 2 iommu's in it.  The catchall iommu has MGAW == 48, and
SAGAW == 4.  The other iommu has MGAW == 39, SAGAW == 2.

The device that's failing the above pgd test is the only device connected
to the non-catchall iommu, which has a smaller address width than the
domain default.  This test is not necessary since the context is in PT
mode and the ASR is ignored.

Thanks to Don Dutile for discovering and debugging this one.

Cc: stable@kernel.org
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The hotplug notifier will call find_domain() to see if the device in
question has been assigned an IOMMU domain. However, this should never
be called for devices with a "dummy" domain, such as graphics devices
when intel_iommu=igfx_off is set and the corresponding IOMMU isn't even
initialised. If you do that, it'll oops as it dereferences the (-1)
pointer.

The notifier function should check iommu_no_mapping() for the
device before doing anything else.

Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Some HP BIOSes report an RMRR region (a region which needs a 1:1 mapping
in the IOMMU for a given device) which has an end address lower than its
start address. Detect that and warn, rather than triggering the
BUG() in dma_pte_clear_range().

Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The BIOS errors where an IOMMU is reported either at zero or a bogus
address are causing problems even when the IOMMU is disabled -- because
interrupt remapping uses the same hardware. Ensure that the checks get
applied for the interrupt remapping initialisation too.

Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Many BIOSes will lie to us about the existence of an IOMMU, and claim
that there is one at an address which actually returns all 0xFF.

We need to detect this early, so that we know we don't have a viable
IOMMU and can set up swiotlb before it's too late.

Cc: stable@kernel.org
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Merge the BIOS workarounds from 2.6.32, and the swiotlb fallback on failure.

Merge branch 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (63 commits)
  x86, Calgary IOMMU quirk: Find nearest matching Calgary while walking up the PCI tree
  x86/amd-iommu: Remove amd_iommu_pd_table
  x86/amd-iommu: Move reset_iommu_command_buffer out of locked code
  x86/amd-iommu: Cleanup DTE flushing code
  x86/amd-iommu: Introduce iommu_flush_device() function
  x86/amd-iommu: Cleanup attach/detach_device code
  x86/amd-iommu: Keep devices per domain in a list
  x86/amd-iommu: Add device bind reference counting
  x86/amd-iommu: Use dev->arch->iommu to store iommu related information
  x86/amd-iommu: Remove support for domain sharing
  x86/amd-iommu: Rearrange dma_ops related functions
  x86/amd-iommu: Move some pte allocation functions in the right section
  x86/amd-iommu: Remove iommu parameter from dma_ops_domain_alloc
  x86/amd-iommu: Use get_device_id and check_device where appropriate
  x86/amd-iommu: Move find_protection_domain to helper functions
  x86/amd-iommu: Simplify get_device_resources()
  x86/amd-iommu: Let domain_for_device handle aliases
  x86/amd-iommu: Remove iommu specific handling from dma_ops path
  x86/amd-iommu: Remove iommu parameter from __(un)map_single
  x86/amd-iommu: Make alloc_new_range aware of multiple IOMMUs
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw: (31 commits)
  GFS2: Fix glock refcount issues
  writeback: remove unused nonblocking and congestion checks (gfs2)
  GFS2: drop rindex glock to refresh rindex list
  GFS2: Tag all metadata with jid
  GFS2: Locking order fix in gfs2_check_blk_state
  GFS2: Remove dirent_first() function
  GFS2: Display nobarrier option in /proc/mounts
  GFS2: add barrier/nobarrier mount options
  GFS2: remove division from new statfs code
  GFS2: Improve statfs and quota usability
  GFS2: Use dquot_send_warning()
  VFS: Export dquot_send_warning
  GFS2: Add set_xquota support
  GFS2: Add get_xquota support
  GFS2: Clean up gfs2_adjust_quota() and do_glock()
  GFS2: Remove constant argument from qd_get()
  GFS2: Remove constant argument from qdsb_get()
  GFS2: Add proper error reporting to quota sync via sysfs
  GFS2: Add get_xstate quota function
  GFS2: Remove obsolete code in quota.c
  ...

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (30 commits)
  TOMOYO: Add recursive directory matching operator support.
  remove CONFIG_SECURITY_FILE_CAPABILITIES compile option
  SELinux: print denials for buggy kernel with unknown perms
  Silence the existing API for capability version compatibility check.
  LSM: Move security_path_chmod()/security_path_chown() to after mutex_lock().
  SELinux: header generation may hit infinite loop
  selinux: Fix warnings
  security: report the module name to security_module_request
  Config option to set a default LSM
  sysctl: require CAP_SYS_RAWIO to set mmap_min_addr
  tpm: autoload tpm_tis based on system PnP IDs
  tpm_tis: TPM_STS_DATA_EXPECT workaround
  define convenient securebits masks for prctl users (v2)
  tpm: fix header for modular build
  tomoyo: improve hash bucket dispersion
  tpm add default function definitions
  LSM: imbed ima calls in the security hooks
  SELinux: add .gitignore files for dynamic classes
  security: remove root_plug
  SELinux: fix locking issue introduced with c6d3aaa4
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6: (50 commits)
  pcmcia: rework the irq_req_t typedef
  pcmcia: remove deprecated handle_to_dev() macro
  pcmcia: pcmcia_request_window() doesn't need a pointer to a pointer
  pcmcia: remove unused "window_t" typedef
  pcmcia: move some window-related code to pcmcia_ioctl.c
  pcmcia: Change window_handle_t logic to unsigned long
  pcmcia: Pass struct pcmcia_socket to pcmcia_get_mem_page()
  pcmcia: Pass struct pcmcia_device to pcmcia_map_mem_page()
  pcmcia: Pass struct pcmcia_device to pcmcia_release_window()
  drivers/pcmcia: remove unnecessary kzalloc
  pcmcia: correct handling for Zoomed Video registers in topic.h
  pcmcia: fix printk formats
  pcmcia: autoload module pcmcia
  pcmcia/staging: update comedi drivers
  PCMCIA: stop duplicating pci_irq in soc_pcmcia_socket
  PCMCIA: ss: allow PCI IRQs > 255
  PCMCIA: soc_common: remove 'dev' member from soc_pcmcia_socket
  PCMCIA: soc_common: constify soc_pcmcia_socket ops member
  PCMCIA: sa1111: remove duplicated initializers
  PCMCIA: sa1111: wrap soc_pcmcia_socket to contain sa1111 specific data
  ...

Use the new unreachable() macro instead of for(;;);
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use the new unreachable() macro instead of for(;;);
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: Heiko Carstens <heiko.carstens@de.ibm.com>
CC: linux390@de.ibm.com
CC: linux-s390@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use the new unreachable() macro instead of while(1);
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
CC: linux-mips@linux-mips.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use the new unreachable() macro instead of for(;;);.  When
allyesconfig is built with a GCC-4.5 snapshot on i686 the size of the
text segment is reduced by 3987 bytes (from 6827019 to 6823032).
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: x86@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Starting with version 4.5, GCC has a new built-in function
__builtin_unreachable() that can be used in places like the kernel's
BUG() where inline assembly is used to transfer control flow.  This
eliminated the need for an endless loop in these places.

The patch adds a new macro 'unreachable()' that will expand to either
__builtin_unreachable() or an endless loop depending on the compiler
version.

Change from v1: Simplify unreachable() for non-GCC 4.5 case.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This patch fixes some ref counting issues. Firstly by moving
the point at which we drop the ref count after a dlm lock
operation has completed we ensure that we never call
gfs2_glock_hold() on a lock with a zero ref count.

Secondly, by using atomic_dec_and_lock() in gfs2_glock_put()
we ensure that at no time will a glock with zero ref count
appear on the lru_list. That means that we can remove the
check for this in our shrinker (which was racy).
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

No one is calling wb_writeback and write_cache_pages with
wbc.nonblocking=1 any more. And lumpy pageout will want to do
nonblocking writeback without the congestion wait.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

When a gfs2 filesystem is grown, it needs to rebuild the rindex list to be able
to use the new space.  gfs2 does this when the rindex is marked not uptodate,
which happens when the rindex glock is dropped.  However, on a single node
setup, there is never any reason to drop the rindex glock, so gfs2 never
invalidates the the rindex. This patch makes gfs2 automatically drop the
rindex glock after filesystem grows, so it can refresh the rindex list.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

There are two spare field in the header common to all GFS2
metadata. One is just the right size to fit a journal id
in it, and this patch updates the journal code so that each
time a metadata block is modified, we tag it with the journal
id of the node which is performing the modification.

The reason for this is that it should make it much easier to
debug issues which arise if we can tell which node was the
last to modify a particular metadata block.

Since the field is updated before the block is written into
the journal, each journal should only contain metadata which
is tagged with its own journal id. The one exception to this
is the journal header block, which might have a different node's
id in it, if that journal was recovered by another node in the
cluster.

Thus each journal will contain a record of which nodes recovered
it, via the journal header.

The other field in the metadata header could potentially be
used to hold information about what kind of operation was
performed, but for the time being we just zero it on each
transaction so that if we use it for that in future, we'll
know that the information (where it exists) is reliable.

I did consider using the other field to hold the journal
sequence number, however since in GFS2's journaling we write
the modified data into the journal and not the original
data, this gives no information as to what action caused the
modification, so I think we can probably come up with a better
use for those 64 bits in the future.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

In some cases we already have the rindex lock when
we enter this function.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This function only had one caller left, and that caller only
called it for leaf blocks, hence one branch of the "if" was
never taken. In addition the call to get_left had already
verified the metadata type, so the function can be reduced
to a single line of code in its caller.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Since the default is barriers on, this only displays the
nobarrier option when that is active.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Currently gfs2 issues barrier unconditionally.  There are various reasons
to disable them, be that just for testing or for stupid devices flushing
large battert backed caches.  Add a nobarrier option that matches xfs and
btrfs for this.  Also add a symmetric barrier option to turn it back on
at remount time.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

It's not necessary to do any 64bit division for the statfs sync code, so
remove it.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2 now has three new mount options, statfs_quantum, quota_quantum and
statfs_percent.  statfs_quantum and quota_quantum simply allow you to
set the tunables of the same name.  Setting setting statfs_quantum to 0
will also turn on the statfs_slow tunable.  statfs_percent accepts an
integer between 0 and 100.  Numbers between 1 and 100 will cause GFS2 to
do any early sync when the local number of blocks free changes by at
least statfs_percent from the totoal number of blocks free.  Setting
statfs_percent to 0 disables this.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This adds support to GFS2 to send quota warnings via netlink.
Also it removes a stray \r which was left over from when the
code used to print warnings on the console.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Sending a message to userspace in a generic format to warn
of events (e.g. quota exceeded) in the quota subsystem is
a generically useful feature. This patch makes some minor
changes to the send_message function from dquot.c renaming
it quota_send_message, moving it to quota.c and exporting it
for use by filesystems which do not use the dquot code.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This patch adds the ability to set GFS2 quota limit and
warning levels via the XFS quota API.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This adds support for viewing the current GFS2 quota settings
via the XFS quota API. The setting of quotas will be addressed
in a later patch. Fields which are not supported here are left
set to zero.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>

Both of these functions contained confusing and in one case
duplicate code. This patch adds a new check in do_glock()
so that we report -ENOENT if we are asked to sync a quota
entry which doesn't exist. Due to the previous patch this is
now reported correctly to userspace.

Also there are a few new comments, and I hope that the code
is easier to understand now.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This function was only ever called with the "create"
argument set to true, so we can remove it.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The "create" argument to qdsb_get() was only ever set to true,
so this patch removes that argument.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

For some reason, the errors were not making it to userspace.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This allows querying of the quota state via the XFS quota
API.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

There is no point in testing for GLF_DEMOTE here, we might as
well always release the glock at that point.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The plan is to add further operations to the gfs2_quotactl_ops
in future patches. The sync operation is easy, so we start with
that one.

We plan to use the XFS quota control functions because they more
closely match the GFS2 ones.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

These two functions are altered so that gfs2_quota_sync may
in future be called directly from the VFS. The GFS2 superblock
changes to a VFS super block and there is an addition of an int
argument which is currently ignored.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

GFS2 needs to call this from under a glock, so we need GFP_NOFS
and I suspect that other filesystems might require this too.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The other patches in this series have been building towards
being able to support cached ACLs like other filesystems. The
only real difference with GFS2 is that we have to invalidate
the cache when we drop a glock, but that is dealt with in earlier
patches.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

To prepare for support for caching of ACLs, this cleans up the GFS2
ACL support by pushing the xattr code back into xattr.c and changing
the acl_get function into one which only returns ACLs so that we
can drop the caching function into it shortly.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>