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>

Replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32)

Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Replace all DMA_64BIT_MASK macro with DMA_BIT_MASK(64)

Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This issue was pointed out by Linus.

In dma_pte_clear_range() in intel-iommu.c

start = PAGE_ALIGN(start);
end &= PAGE_MASK;
npages = (end - start) / VTD_PAGE_SIZE;

In partial page case, start could be bigger than end and npages will be
negative.

Currently the issue doesn't show up as a real bug in because start and 
end have been aligned to page boundary already by all callers. So the 
issue has been hidden. But it is dangerous programming practice.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

It's possible for a device in the drhd->devices[] array to be NULL if
it wasn't found at boot time, which means we have to check for that
case.
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>

When the DMAR table identifies that a PCI-PCI bridge belongs to a given
IOMMU, that means that the bridge and all devices behind it should be
associated with the IOMMU. Not just the bridge itself.

This fixes the device_to_iommu() function accordingly.

(It's broken if you have the same PCI bus numbers in multiple domains,
but this function was always broken in that way; I'll be dealing with
that later).
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

interrupt remapping must be enabled before enabling x2apic, but
interrupt remapping doesn't depend on x2apic, it can be used
separately. Enable interrupt remapping in init_dmars even x2apic
is not supported.

[dwmw2: Update Kconfig accordingly, fix build with INTR_REMAP && !X2APIC]
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch implements the suspend and resume feature for Intel IOMMU
DMAR. It hooks to kernel suspend and resume interface. When suspend happens, it
saves necessary hardware registers. When resume happens, it restores the
registers and restarts IOMMU by enabling translation, setting up root entry, and
re-enabling queued invalidation.
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>

The problem is in dma_pte_clear_range and dma_pte_free_pagetable. When
intel_unmap_single and intel_unmap_sg call them, the end address may be
zero if the 'start_addr + size' rounds up. So no PTE gets cleared. The
uncleared PTE fires the BUG_ON when it's used again to create new mappings.

After I modified dma_pte_clear_range a bit, the BUG_ON is gone.

Tested both 32 and 32 PAE modes on Intel X58 and Q35 platforms.
Signed-off-by: NYu Zhao <yu.zhao@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

If we fix a few highmem-related thinkos and a couple of printk format
warnings, the Intel IOMMU driver works fine in a 32-bit kernel.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

When assign a device behind conventional PCI bridge or PCIe to
PCI/PCI-x bridge to a domain, it must assign its bridge and may
also need to assign secondary interface to the same domain.

Dependent assignment is already there, but dependent
deassignment is missed when detach device from virtual machine.
This results in conventional PCI device assignment failure after
it has been assigned once. This patch addes dependent
deassignment, and fixes the issue.
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The user can request to enable snooping control through VT-d page table.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This iommu_op can tell if domain have a specific capability, like snooping
control for Intel IOMMU, which can be used by other components of kernel to
adjust the behaviour.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Snooping control enabled IOMMU to guarantee DMA cache coherency and thus reduce
software effort (VMM) in maintaining effective memory type.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

According to kerneljanitors todo list all printk calls (beginning
a new line) should have an according KERN_* constant.
Those are the missing pieces here for the pci subsystem.
Signed-off-by: NFrank Seidel <frank@f-seidel.de>
Reviewed-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

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: 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>

This is the cause of the DMA faults and disk corruption that people have
been seeing. Some chipsets neglect to report the RWBF "capability" --
the flag which says that we need to flush the chipset write-buffer when
changing the DMA page tables, to ensure that the change is visible to
the IOMMU.

Override that bit on the affected chipsets, and everything is happy
again.

Thanks to Chris and Bhavesh and others for helping to debug.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Tested-by: NChris Wright <chrisw@sous-sol.org>
Reviewed-by: NBhavesh Davda <bhavesh@vmware.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is the cause of the DMA faults and disk corruption that people have
been seeing. Some chipsets neglect to report the RWBF "capability" --
the flag which says that we need to flush the chipset write-buffer when
changing the DMA page tables, to ensure that the change is visible to
the IOMMU.

Override that bit on the affected chipsets, and everything is happy
again.

Thanks to Chris and Bhavesh and others for helping to debug.

Should resolve:

  https://bugzilla.redhat.com/show_bug.cgi?id=479996
  http://bugzilla.kernel.org/show_bug.cgi?id=12578Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Tested-and-acked-by: NChris Wright <chrisw@sous-sol.org>
Reviewed-by: NBhavesh Davda <bhavesh@vmware.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Due to recurring issues with DMAR support on certain platforms.
There's a number of filesystem corruption incidents reported:

  https://bugzilla.redhat.com/show_bug.cgi?id=479996
  http://bugzilla.kernel.org/show_bug.cgi?id=12578

Provide a Kconfig option to change whether it is enabled by
default.

If disabled, it can still be reenabled by passing intel_iommu=on to the
kernel. Keep the .config option off by default.
Signed-off-by: NKyle McMartin <kyle@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-By: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The dma ops unification enables X86 and IA64 to share intel_dma_ops so
we can make dma mapping functions static. This also remove unused
intel_map_single().
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

dma_mapping_error is used to see if dma_map_single and dma_map_page
succeed. IA64 VT-d dma_mapping_error always says that dma_map_single
is successful even though it could fail. Note that X86 VT-d works
properly in this regard.

This patch fixes IA64 VT-d dma_mapping_error by adding VT-d's own
dma_mapping_error() that works for both X86_64 and IA64. VT-d uses
zero as an error dma address so VT-d's dma_mapping_error returns 1 if
a passed dma address is zero (as x86's VT-d dma_mapping_error does
now).
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With some broken BIOSs when VT-d is enabled, the data structures are
filled incorrectly. This can cause a NULL pointer dereference in very
early boot.
Signed-off-by: NDirk Hohndel <hohndel@linux.intel.com>
Acked-by: NYu Zhao <yu.zhao@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This converts X86 and IA64 to use include/linux/dma-mapping.h.

It's a bit large but pretty boring. The major change for X86 is
converting 'int dir' to 'enum dma_data_direction dir' in DMA mapping
operations. The major changes for IA64 is using map_page and
unmap_page instead of map_single and unmap_single.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch converts dma_map_single and dma_unmap_single to use
map_page and unmap_page respectively and removes unnecessary
map_single and unmap_single in struct dma_mapping_ops.

This leaves intel-iommu's dma_map_single and dma_unmap_single since
IA64 uses them. They will be removed after the unification.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This is a preparation of struct dma_mapping_ops unification. We use
map_page and unmap_page instead of map_single and unmap_single.

This uses a temporary workaround, ifdef X86_64 to avoid IA64
build. The workaround will be removed after the unification. Well,
changing x86's struct dma_mapping_ops could break IA64. It's just
wrong. It's one of problems that this patchset fixes.

We will remove map_single and unmap_single hooks in the last patch in
this patchset.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NMike Day <ncmike@ncultra.org>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

When domain is related to multiple iommus, need to check if the minimum agaw is sufficient for the mapped memory
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

These APIs are used by KVM to use VT-d
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

vm_domid won't be set in context, find available domain id for a device from its iommu.

For a virtual machine domain, a default agaw will be set, and skip top levels of page tables for iommu which has less agaw than default.
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

virtual machine domain is different from native DMA-API domain, implement separate allocation and free functions for virtual machine domain.
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Because virtual machine domain may have multiple devices from different iommus, it cannot use __iommu_flush_cache.

In some common low level functions, use domain_flush_cache instead of __iommu_flush_cache. On the other hand, in some functions, iommu can is specified or domain cannot be got, still use __iommu_flush_cache
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>