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: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Weidong Han <weidong@intel.com>
Signed-off-by: David 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: David 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: David 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: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. 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: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: new interfaces (not yet used)
Routines for disabling queued invalidation and interrupt remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. 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: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. 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: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: David 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: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: David 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: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg 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: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This merges branches irq/genirq, irq/sparseirq-v4, timers/hpet-percpu
and x86/uv.
The sparseirq branch is just preliminary groundwork: no sparse IRQs are
actually implemented by this tree anymore - just the new APIs are added
while keeping the old way intact as well (the new APIs map 1:1 to
irq_desc[]). The 'real' sparse IRQ support will then be a relatively
small patch ontop of this - with a v2.6.29 merge target.
* 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (178 commits)
genirq: improve include files
intr_remapping: fix typo
io_apic: make irq_mis_count available on 64-bit too
genirq: fix name space collisions of nr_irqs in arch/*
genirq: fix name space collision of nr_irqs in autoprobe.c
genirq: use iterators for irq_desc loops
proc: fixup irq iterator
genirq: add reverse iterator for irq_desc
x86: move ack_bad_irq() to irq.c
x86: unify show_interrupts() and proc helpers
x86: cleanup show_interrupts
genirq: cleanup the sparseirq modifications
genirq: remove artifacts from sparseirq removal
genirq: revert dynarray
genirq: remove irq_to_desc_alloc
genirq: remove sparse irq code
genirq: use inline function for irq_to_desc
genirq: consolidate nr_irqs and for_each_irq_desc()
x86: remove sparse irq from Kconfig
genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n
...
This was introduced by commit 1886e8a90a
("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: David 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: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: David 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: Youquan Song <youquan.song@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: David 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: Youquan Song <youquan.song@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: David 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: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: David 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: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo 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: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
initialize the return value in dmar_parse_dev()
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo 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: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo 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: Kay, Allen M <allen.m.kay@intel.com>
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Ben-Ami Yassour <benami@il.ibm.com>
Signed-off-by: Amit Shah <amit.shah@qumranet.com>
Acked-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
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: Suresh 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: Ingo 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: Suresh 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: Ingo 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: Suresh 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: Ingo Molnar <mingo@elte.hu>
Clean up the intel-iommu code related to deferred iommu flush logic. There is
no need to allocate all the iommu's as a sequential array.
This will be used later in the interrupt-remapping patch series to
allocate iommu much early and individually for each device remapping
hardware unit.
Signed-off-by: Suresh 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: Ingo Molnar <mingo@elte.hu>
code reorganization of the generic Intel vt-d parsing related routines and linux
iommu routines specific to Intel vt-d.
drivers/pci/dmar.c now contains the generic vt-d parsing related routines
drivers/pci/intel_iommu.c contains the iommu routines specific to vt-d
Signed-off-by: Suresh 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: Ingo Molnar <mingo@elte.hu>
The following is a clean up and correction of the copyright holding
entities for the files associated with the intel iommu code.
Signed-off-by: <mgross@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I would like to potentially move the sparc64 IOMMU code over to using
the nice new drivers/pci/iova.[ch] code for free area management..
In order to do that we have to detach the IOMMU page size assumptions
which only really need to exist in the intel-iommu.[ch] code.
This patch attempts to implement that.
[akpm@linux-foundation.org: build fix]
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add and changes a few sanity checks in dmar.c.
1. The haw field in ACPI DMAR table in VT-d spec doesn't describe the
range of haw. But since DMA page size is 4KB in DMA remapping, haw
should be at least 4KB. The current VT-d code in dmar.c returns failure
when haw==0. This sanity check is not accurate and execution can pass
when haw is less than one page size 4KB. This patch changes the haw
sanity check to validate if haw is less than 4KB.
2. Add dmar_rmrr_units verification.
3. Add parse_dmar_table() verification.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: mark gross <mgross@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch supports the upcomming Intel IOMMU hardware a.k.a. Intel(R)
Virtualization Technology for Directed I/O Architecture and the hardware spec
for the same can be found here
http://www.intel.com/technology/virtualization/index.htm
FAQ! (questions from akpm, answers from ak)
> So... what's all this code for?
>
> I assume that the intent here is to speed things up under Xen, etc?
Yes in some cases, but not this code. That would be the Xen version of this
code that could potentially assign whole devices to guests. I expect this to
be only useful in some special cases though because most hardware is not
virtualizable and you typically want an own instance for each guest.
Ok at some point KVM might implement this too; i likely would use this code
for this.
> Do we
> have any benchmark results to help us to decide whether a merge would be
> justified?
The main advantage for doing it in the normal kernel is not performance, but
more safety. Broken devices won't be able to corrupt memory by doing random
DMA.
Unfortunately that doesn't work for graphics yet, for that need user space
interfaces for the X server are needed.
There are some potential performance benefits too:
- When you have a device that cannot address the complete address range an
IOMMU can remap its memory instead of bounce buffering. Remapping is likely
cheaper than copying.
- The IOMMU can merge sg lists into a single virtual block. This could
potentially speed up SG IO when the device is slow walking SG lists. [I
long ago benchmarked 5% on some block benchmark with an old MPT Fusion; but
it probably depends a lot on the HBA]
And you get better driver debugging because unexpected memory accesses from
the devices will cause a trappable event.
>
> Does it slow anything down?
It adds more overhead to each IO so yes.
This patch:
Add support for early detection and parsing of DMAR's (DMA Remapping) reported
to OS via ACPI tables.
DMA remapping(DMAR) devices support enables independent address translations
for Direct Memory Access(DMA) from Devices. These DMA remapping devices are
reported via ACPI tables and includes pci device scope covered by these DMA
remapping device.
For detailed info on the specification of "Intel(R) Virtualization Technology
for Directed I/O Architecture" please see
http://www.intel.com/technology/virtualization/index.htm
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Greg KH <greg@kroah.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
