This patch implements a fallback to the GART IOMMU if this
is possible and the AMD IOMMU initialization failed.
Otherwise the fallback would be nommu which is very
problematic on machines with more than 4GB of memory or
swiotlb which hurts io-performance.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

When request_mem_region fails the error path tries to
disable the IOMMUs. This accesses the mmio-region which was
not allocated leading to a kernel crash. This patch fixes
the issue.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch adds a command line option to tell the AMD IOMMU
driver to not initialize any IOMMU it finds.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

To catch future potential issues we can add a warning whenever we issue
a command before the command buffer is fully initialized.
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Hit another kdump problem as reported by Neil Horman.  When initializaing
the IOMMU, we attach devices to their domains before the IOMMU is
fully (re)initialized.  Attaching a device will issue some important
invalidations.  In the context of the newly kexec'd kdump kernel, the
IOMMU may have stale cached data from the original kernel.  Because we
do the attach too early, the invalidation commands are placed in the new
command buffer before the IOMMU is updated w/ that buffer.  This leaves
the stale entries in the kdump context and can renders device unusable.
Simply enable the IOMMU before we do the attach.

Cc: stable@kernel.org
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Since acpi_table_parse ignores the return values of the
parsing function this patch introduces a workaround and
reports these errors upstream via a global variable.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch moves the initialization of the iommu-api out of
the dma-ops initialization code. This ensures that the
iommu-api is initialized even with iommu=pt.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The assumption that acpi_table_parse passes the return value
of the hanlder function to the caller proved wrong
recently. The return value of the handler function is
totally ignored. This makes the initialization code for AMD
IOMMU buggy in a way that could cause a kernel panic on
initialization. This patch fixes the issue in the AMD IOMMU
driver.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The device change notifier is initialized in the dma_ops
initialization path. But this path is never executed for
iommu=pt. Move the notifier initialization to IOMMU hardware
init code to fix this.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The data structure changes to use dev->archdata.iommu field
broke the iommu=pt mode because in this case the
dev->archdata.iommu was left uninitialized. This moves the
inititalization of the devices into the main init function
and fixes the problem.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Commit ae21ee65 "PCI: acs p2p upsteram
forwarding enabling" doesn't actually enable ACS.

Add a function to pci core to allow an IOMMU to request that ACS
be enabled.  The existing mechanism of using iommu_found() in the pci
core to know when ACS should be enabled doesn't actually work due to
initialization order;  iommu has only been detected not initialized.

Have Intel and AMD IOMMUs request ACS, and Xen does as well during early
init of dom0.

Cc: Allen Kay <allen.m.kay@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The data that was stored in this table is now available in
dev->archdata.iommu. So this table is not longer necessary.
This patch removes the remaining uses of that variable and
removes it from the code.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch makes device isolation mandatory and removes
support for the amd_iommu=share option. This simplifies the
code in several places.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The non-present cache flag was IOMMU local until now which
doesn't make sense. Make this a global flag so we can remove
the lase user of 'struct iommu' in the map/unmap path.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch adds code to keep a global list of all protection
domains. This allows to simplify the resume code.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch adds an index field to struct amd_iommu which can
be used to lookup it up in an array. This index will be used
in struct protection_domain to keep track which protection
domain has devices behind which IOMMU.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch updates the copyright headers in the relevant AMD
IOMMU driver files to match the date of the latest changes.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch moves all function declarations which are only
used inside the driver code to a seperate header file.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This function may be called on the resume path and can not
be dropped after booting.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

If HW IOMMU initialization fails (Intel VT-d often does this,
typically due to BIOS bugs), we fall back to nommu. It doesn't
work for the majority since nowadays we have more than 4GB
memory so we must use swiotlb instead of nommu.

The problem is that it's too late to initialize swiotlb when HW
IOMMU initialization fails. We need to allocate swiotlb memory
earlier from bootmem allocator. Chris explained the issue in
detail:

  http://marc.info/?l=linux-kernel&m=125657444317079&w=2

The current x86 IOMMU initialization sequence is too complicated
and handling the above issue makes it more hacky.

This patch changes x86 IOMMU initialization sequence to handle
the above issue cleanly.

The new x86 IOMMU initialization sequence are:

1. we initialize the swiotlb (and setting swiotlb to 1) in the case
   of (max_pfn > MAX_DMA32_PFN && !no_iommu). dma_ops is set to
   swiotlb_dma_ops or nommu_dma_ops. if swiotlb usage is forced by
   the boot option, we finish here.

2. we call the detection functions of all the IOMMUs

3. the detection function sets x86_init.iommu.iommu_init to the
   IOMMU initialization function (so we can avoid calling the
   initialization functions of all the IOMMUs needlessly).

4. if the IOMMU initialization function doesn't need to swiotlb
   then sets swiotlb to zero (e.g. the initialization is
   sucessful).

5. if we find that swiotlb is set to zero, we free swiotlb
   resource.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: chrisw@sous-sol.org
Cc: dwmw2@infradead.org
Cc: joerg.roedel@amd.com
Cc: muli@il.ibm.com
LKML-Reference: <1257849980-22640-10-git-send-email-fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This changes amd_iommu_detect() to set amd_iommu_init to
iommu_init hook if amd_iommu_detect() finds the AMD IOMMU.

We can kill the code to check if we found the IOMMU in
amd_iommu_init() since amd_iommu_detect() sets amd_iommu_init()
only when it found the IOMMU.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: chrisw@sous-sol.org
Cc: dwmw2@infradead.org
Cc: joerg.roedel@amd.com
Cc: muli@il.ibm.com
LKML-Reference: <1257849980-22640-5-git-send-email-fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch cleans up pci_iommu_shutdown() a bit to use
x86_platform (similar to how IA64 initializes an IOMMU driver).

This adds iommu_shutdown() to x86_platform to avoid calling
every IOMMUs' shutdown functions in pci_iommu_shutdown() in
order. The IOMMU shutdown functions are platform specific (we
don't have multiple different IOMMU hardware) so the current way
is pointless.

An IOMMU driver sets x86_platform.iommu_shutdown to the shutdown
function if necessary.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: joerg.roedel@amd.com
LKML-Reference: <20091027163358F.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The function iommu_feature_disable is required on system
shutdown to disable the IOMMU but it is marked as __init.
This may result in a panic if the memory is reused. This
patch fixes this bug.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

There is an erratum for IOMMU hardware which documents
undefined behavior when forwarding SMI requests from
peripherals and the DTE of that peripheral has a sysmgt
value of 01b. This problem caused weird IO_PAGE_FAULTS in my
case.
This patch implements the suggested workaround for that
erratum into the AMD IOMMU driver.  The erratum is
documented with number 63.

Cc: stable@kernel.org
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch enables the passthrough mode for AMD IOMMU by
running the initialization function when iommu=pt is passed
on the kernel command line.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch factors parts of the command buffer
initialization code into a seperate function which can be
used to reset the command buffer later.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The 'IOMMU: ' prefix is not necessary because the
DUMP_printk macro already prints its own prefix.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch replaces the "AMD IOMMU" printk strings with the
official name for the hardware: "AMD-Vi".
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The setting of this variable got lost during the suspend/resume
implementation.  But keeping this variable zero causes a divide-by-zero
error in the interrupt handler. This patch fixes this.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

An alias entry in the ACPI table means that the device can send requests to the
IOMMU with both device ids, its own and the alias. This is not handled properly
in the ACPI init code. This patch fixes the issue.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Now that enable_iommus() will call iommu_disable() for each iommu,
the call to disable_iommus() during resume is redundant.  Also, the order
for an invalidation is to invalidate device table entries first, then
domain translations.
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

These registers may contain values from previous kernels. So reset them
to known values before enable the event buffer again.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

The IOMMU spec states that IOMMU behavior may be undefined when the
IOMMU registers are rewritten while command or event buffer is enabled.
Disable them in IOMMU disable path.
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

When the IOMMU stays enabled the BIOS may not be able to finish the
machine shutdown properly. So disable the hardware on shutdown.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This parameter is not longer necessary when aperture increases
dynamically.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch puts everything together and enables suspend/resume support
in the AMD IOMMU driver.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This patch makes sure that no function required for suspend/resume of
AMD IOMMU driver is thrown away after boot.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This function is required for suspend/resume support with AMD IOMMU
enabled.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Current hardware uses msi instead of msi-x so this code it not necessary
and can not be tested. The best thing is to drop this code.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>