Yet another reason why trusting this stuff to the BIOS was a bad idea.
The HP DC7900 BIOS reports an iommu at an address which just returns all
ones, when VT-d is disabled in the BIOS.

Fix up the missing iounmap in the error paths while we're at it.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Support device IOTLB invalidation to flush the translation cached
in the Endpoint.
Signed-off-by: NYu Zhao <yu.zhao@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Parse the Root Port ATS Capability Reporting Structure in the DMA
Remapping Reporting Structure ACPI table.
Signed-off-by: NYu Zhao <yu.zhao@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

dmar_set_interrupt feigns success when arch_setup_dmar_msi
fails, return error value.
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

As we just did for context cache flushing, clean up the logic around
whether we need to flush the iotlb or just the write-buffer, depending
on caching mode.

Fix the same bug in qi_flush_iotlb() that qi_flush_context() had -- it
isn't supposed to be returning an error; it's supposed to be returning a
flag which triggers a write-buffer flush.

Remove some superfluous conditional write-buffer flushes which could
never have happened because they weren't for non-present-to-present
mapping changes anyway.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

It really doesn't make a lot of sense to have some of the logic to
handle caching vs. non-caching mode duplicated in qi_flush_context() and
__iommu_flush_context(), while the return value indicates whether the
caller should take other action which depends on the same thing.

Especially since qi_flush_context() thought it was returning something
entirely different anyway.

This patch makes qi_flush_context() and __iommu_flush_context() both
return void, removes the 'non_present_entry_flush' argument and makes
the only call site which _set_ that argument to 1 do the right thing.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The patch adds kernel parameter intel_iommu=pt to set up pass through
mode in context mapping entry. This disables DMAR in linux kernel; but
KVM still runs on VT-d and interrupt remapping still works.

In this mode, kernel uses swiotlb for DMA API functions but other VT-d
functionalities are enabled for KVM. KVM always uses multi level
translation page table in VT-d. By default, pass though mode is disabled
in kernel.

This is useful when people don't want to enable VT-d DMAR in kernel but
still want to use KVM and interrupt remapping for reasons like DMAR
performance concern or debug purpose.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Acked-by: NWeidong Han <weidong@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

If the BIOS does something obviously stupid, like claiming that the
registers for the IOMMU are at physical address zero, then print a nasty
message and abort, rather than trying to set up the IOMMU and then later
panicking.

It's becoming more and more obvious that trusting this stuff to the BIOS
was a mistake.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

We were comparing {bus,devfn} and assuming that a match meant it was the
same device. It doesn't -- the same {bus,devfn} can exist in
multiple PCI domains. Include domain number in device identification
(and call it 'segment' in most places, because there's already a lot of
references to 'domain' which means something else, and this code is
infected with ACPI thinking already).
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch supports queued invalidation suspend/resume.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Impact: invalid use of GFP_KERNEL in interrupt context

Queued invalidation and interrupt-remapping will get initialized with
interrupts disabled (while enabling interrupt-remapping). So use
GFP_ATOMIC instead of GFP_KERNEL for memory alloacations.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Impact: cleanup/sanitization

Start from a sane state while enabling dma and interrupt-remapping, by
clearing the previous recorded faults and disabling previously
enabled queued invalidation and interrupt-remapping.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Impact: new interfaces (not yet used)

Routines for disabling queued invalidation and interrupt remapping.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Impact: interface augmentation (not yet used)

Enable fault handling flow for intr-remapping aswell. Fault handling
code now shared by both dma-remapping and intr-remapping.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Impact: code movement

Move page fault handling code to dmar.c
This will be shared both by DMA-remapping and Intr-remapping code.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

I have a SuperMicro C2SBX motherboard with BIOS revision 1.0b.  With vt-d
enabled in the BIOS, Linux gets into an endless loop printing
"DMAR:Unknown DMAR structure type" when booting.  Here is the DMAR ACPI
table:

DMAR @ 0x7fe86dec
  0000: 44 4d 41 52 98 00 00 00 01 6f 49 6e 74 65 6c 20  DMAR.....oIntel
  0010: 4f 45 4d 44 4d 41 52 20 00 00 04 06 4c 4f 48 52  OEMDMAR ....LOHR
  0020: 01 00 00 00 23 00 00 00 00 00 00 00 00 00 00 00  ....#...........
  0030: 01 00 58 00 00 00 00 00 00 a0 e8 7f 00 00 00 00  ..X.............
  0040: ff ff ef 7f 00 00 00 00 01 08 00 00 00 00 1d 00  ................
  0050: 01 08 00 00 00 00 1d 01 01 08 00 00 00 00 1d 02  ................
  0060: 01 08 00 00 00 00 1d 07 01 08 00 00 00 00 1a 00  ................
  0070: 01 08 00 00 00 00 1a 01 01 08 00 00 00 00 1a 02  ................
  0080: 01 08 00 00 00 00 1a 07 01 08 00 00 00 00 1a 07  ................
  0090: c0 00 68 00 04 10 66 60                          ..h...f`

Here are the messages printed by the kernel:

DMAR:Host address width 36
DMAR:RMRR base: 0x000000007fe8a000 end: 0x000000007fefffff
DMAR:Unknown DMAR structure type
DMAR:Unknown DMAR structure type
DMAR:Unknown DMAR structure type
...

Although I not very familiar with ACPI, to me it looks like struct
acpi_dmar_header::length == 0x0058 is incorrect, causing
parse_dmar_table() to look at an invalid offset on the next loop.  This
offset happens to have struct acpi_dmar_header::length == 0x0000, which
prevents the loop from ever terminating.  This patch checks for this
condition and bails out instead of looping forever.
Signed-off-by: NTony Battersby <tonyb@cybernetics.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Pawel reported:
------------[ cut here ]------------
WARNING: at arch/x86/mm/ioremap.c:616 check_early_ioremap_leak+0x52/0x67()
Hardware name:
Debug warning: early ioremap leak of 1 areas detected.
Modules linked in:
Pid: 1, comm: swapper Not tainted 2.6.29-rc4-tip #2
...
Reported-by: NPawel Dziekonski <dzieko@gmail.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When hardware detects any error with a descriptor from the invalidation
queue, it stops fetching new descriptors from the queue until software
clears the Invalidation Queue Error bit in the Fault Status register.
Following fix handles the IQE so the kernel won't be trapped in an
infinite loop.
Signed-off-by: NYu Zhao <yu.zhao@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This fix should be safe since iommu->agaw is only used in intel-iommu.c.
And this file is only compiled with DMAR=y.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

"SAGAW" capability may be different across iommus. Use a default agaw, but if default agaw is not supported in some iommus, choose a less supported agaw.
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

On platforms with multiple PCI segments, any of the segments can have a DRHD
with INCLUDE_PCI_ALL flag. So need to check the DRHD's segment number against
the PCI device's when searching its DRHD.
Signed-off-by: NYu Zhao <yu.zhao@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

This was introduced by commit 1886e8a9
("x64, x2apic/intr-remap: code re-structuring, to be used by both DMA
and Interrupt remapping"). It was causing bogus results to be returned
from dmar_parse_dev() when the first unit with the INCLUDE_ALL flag was
processed.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The current Intel IOMMU code assumes that both host page size and Intel
IOMMU page size are 4KiB. The first patch supports variable page size.
This provides support for IA64 which has multiple page sizes.

This patch also adds some other code hooks for IA64 platform including
DMAR_OPERATION_TIMEOUT definition.

[dwmw2: some cleanup]
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Now that we have DMA-remapping support for queued invalidation, we
can enable both DMA-remapping and interrupt-remapping at the same time.
Signed-off-by: NYouquan Song <youquan.song@intel.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Implement context cache invalidate and IOTLB invalidation using
queued invalidation interface. This interface will be used by
DMA remapping, when queued invalidation is supported.
Signed-off-by: NYouquan Song <youquan.song@intel.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Next patch in the series will use queued invalidation interface
qi_submit_sync() for DMA-remapping aswell, which can be called from interrupt
context.

So use spin_lock_irqsave() instead of spin_lock() in qi_submit_sync().
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NYouquan Song <youquan.song@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

It is possible that,
instead of PCI endpoint/sub-hierarchy structures, only IO-APIC/HPET
devices may be reported under device scope structures. Fix the devices_cnt
error check, which cares about only PCI structures and removes the
dma-remapping unit structure (dmaru) when the devices_cnt is zero
and include_all flag is not set.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In dmar_dev_scope_init(), functions called under for_each_drhd_unit()/
for_each_rmrr_units() can delete the list entry under some error conditions.

So we should use list_for_each_entry_safe() for safe traversal.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

initialize the return value in dmar_parse_dev()
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Very early detection of the DMAR tables will setup fixmap mapping. For
parsing these tables later (while enabling dma and/or interrupt remapping),
early fixmap mapping shouldn't be used. Fix it by calling table detection
routines again, which will call generic apci_get_table() for setting up
the correct mapping.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch extends the VT-d driver to support KVM

[Ben: fixed memory pinning]
[avi: move dma_remapping.h as well]
Signed-off-by: NKay, Allen M <allen.m.kay@intel.com>
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NBen-Ami Yassour <benami@il.ibm.com>
Signed-off-by: NAmit Shah <amit.shah@qumranet.com>
Acked-by: NMark Gross <mgross@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

RMRRs do not necessarily have to be present on all VT-d capable platforms.
The printk is just informational and does not need to be followed by an error
return.
Signed-off-by: NYong Y Wang <yong.y.wang@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: mark gross <mgross@linux.intel.com>
Cc: Keshavamurthy, Anil S <anil.s.keshavamurthy@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Interrupt-remapping enables queued invalidation. And once queued invalidation
is enabled, IOTLB invalidation also needs to use the queued invalidation
mechanism and the register based IOTLB invalidation doesn't work.

For now, Support for IOTLB invalidation using queued invalidation is
missing. Meanwhile, disable DMA-remapping, if Interrupt-remapping
support is detected.

For the meanwhile, if someone wants to really enable DMA-remapping, they
can use nox2apic, which will disable interrupt-remapping and as such
doesn't enable queued invalidation.

And given that none of the release platforms support intr-remapping yet,
we should be ok for this temporary hack.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Interrupt remapping (part of Intel Virtualization Tech for directed I/O)
infrastructure.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Queued invalidation (part of Intel Virtualization Technology for
Directed I/O architecture) infrastructure.

This will be used for invalidating the interrupt entry cache in the
case of Interrupt-remapping and IOTLB invalidation in the case
of DMA-remapping.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Parse the vt-d device scope structures to find the mapping between IO-APICs
and the interrupt remapping hardware units.

This will be used later for enabling Interrupt-remapping for IOAPIC devices.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Presence of RMRR structures is not compulsory for enabling DMA-remapping.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NYong Y Wang <yong.y.wang@intel.com>
Cc: Yong Y Wang <yong.y.wang@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

DMA remapping specific code covered with CONFIG_DMAR in
the generic code which will also be used later for enabling Interrupt-remapping.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Allocate the iommu during the parse of DMA remapping hardware
definition structures. And also, introduce routines for device
scope initialization which will be explicitly called during
dma-remapping initialization.

These will be used for enabling interrupt remapping separately from the
existing DMA-remapping enabling sequence.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>