The flush queue is the equivalent to defered-flushing in the
Intel VT-d driver. This patch sets up the data structures
needed for this.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This parameter is not required anymore because the
iova-allocations are always aligned to its size.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

There are other remains in the code from the old allocatore.
Remove them all.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Remove the old address allocation code and make use of the
generic IOVA allocator that is also used by other dma-ops
implementations.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Use the iommu-api map/unmap functions instead. This will be
required anyway when IOVA code is used for address
allocation.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Make this function ready to be used in the DMA-API path.
Reorder parameters a bit while at it.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

It is used to reserve the dm-regions in the iova-tree.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Put the MSI-range, the HT-range and the MMIO ranges of PCI
devices into that range, so that these addresses are not
allocated for DMA.

Copy this address list into every created dma_ops_domain.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Use it later for allocating the IO virtual addresses.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Include the generic IOVA code to make use of it in the AMD
IOMMU driver too.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This new call-back will be used by the iommu driver to do
reserve the given dm_region in its iova space before the
mapping is created.

The call-back is temporary until the dma-ops implementation
is part of the common iommu code.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The default domain for a device might also be
identity-mapped. In this case the kernel would crash when
unity mappings are defined for the device. Fix that by
making sure the domain is a dma_ops domain.

Fixes: 0bb6e243 ('iommu/amd: Support IOMMU_DOMAIN_DMA type allocation')
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

alloc_workqueue replaces deprecated create_workqueue().

A dedicated workqueue has been used since the workitem (viz
&fault->work), is involved in IO page-fault handling.
WQ_MEM_RECLAIM has been set to guarantee forward progress under memory
pressure, which is a requirement here.
Since there are only a fixed number of work items, explicit concurrency
limit is unnecessary.
Signed-off-by: NBhaktipriya Shridhar <bhaktipriya96@gmail.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

AMD has more drivers will use ACPI to platform bus driver later,
all those devices need iommu support, for example: eMMC driver.

For latest AMD eMMC controller, it will utilize sdhci-acpi.c driver,
which will rely on platform bus to match device and driver, where we
will set 'dev' of struct platform_device as map_sg parameter passing
to iommu driver for DMA request, so the iommu-ops are needed on the
platform bus.
Signed-off-by: NWan Zongshun <Vincent.Wan@amd.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
       unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> # For nvmem part
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now that we can accurately reflect the context format we choose for each
domain, do that instead of imposing the global lowest-common-denominator
restriction and potentially ending up with nothing. We currently have a
strict 1:1 correspondence between domains and context banks, so we don't
need to entertain the possibility of multiple formats _within_ a domain.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
[rm: split from original patch, added SMMUv3]
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The statistics are not really used for anything and should
be replaced by generic and per-device statistic counters.
Remove the code for now.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Now that we know exactly which page sizes our caller wants to use in the
given domain, we can restrict higher-order allocation attempts to just
those sizes, if any, and avoid wasting any time or effort on other sizes
which offer no benefit. In the same vein, this also lets us accommodate
a minimum order greater than 0 for special cases.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Tested-by: NYong Wu <yong.wu@mediatek.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Many IOMMUs support multiple page table formats, meaning that any given
domain may only support a subset of the hardware page sizes presented in
iommu_ops->pgsize_bitmap. There are also certain use-cases where the
creator of a domain may want to control which page sizes are used, for
example to force the use of hugepage mappings to reduce pagetable walk
depth.

To this end, add a per-domain pgsize_bitmap to represent the subset of
page sizes actually in use, to make it possible for domains with
different requirements to coexist.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
[rm: hijacked and rebased original patch with new commit message]
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

As a set of driver-provided callbacks and static data, there is no
compelling reason for struct iommu_ops to be mutable in core code, so
enforce const-ness throughout.
Acked-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Stop wasting IOVA space by over-aligning scatterlist segments for a
theoretical worst-case segment boundary mask, and instead take the real
limits into account to merge consecutive segments wherever appropriate,
so our callers can benefit from getting back nicely simplified lists.

This also represents the last piece of functionality wanted by users of
the current arch/arm implementation, thus brings us a small step closer
to converting that over to the common code.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

According MMU-500r2 TRM, section 3.7.1 Auxiliary Control registers,
You can modify ACTLR only when the ACR.CACHE_LOCK bit is 0.

So before clearing ARM_MMU500_ACTLR_CPRE of each context bank,
need clear CACHE_LOCK bit of ACR register first.

Since CACHE_LOCK bit is only present in MMU-500r2 onwards,
need to check the major number of IDR7.
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NPeng Fan <van.freenix@gmail.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

The 64KB Translation Granule Supplement to the SMMUv1 architecture
allows an SMMUv1 implementation to support 64KB pages for stage 2
translations, using a constrained VMSAv8 descriptor format limited
to 40-bit addresses. Now that we can freely mix and match context
formats, we can actually handle having 4KB pages via an AArch32
context but 64KB pages via an AArch64 context, so plumb it in.

It is assumed that any implementations will have hardware capabilities
matching the format constraints, thus obviating the need for excessive
sanity-checking; this is the case for MMU-401, the only ARM Ltd.
implementation.

CC: Eric Auger <eric.auger@linaro.org>
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

The way the driver currently forces an AArch32 or AArch64 context format
based on the kernel config and SMMU architecture version is suboptimal,
in that it makes it very hard to support oddball mix-and-match cases
like the SMMUv1 64KB supplement, or situations where the reduced table
depth of an AArch32 short descriptor context may be desirable under an
AArch64 kernel. It also only happens to work on current implementations
which do support all the relevant formats.

Introduce an explicit notion of context format, so we can manage that
independently and get rid of the inflexible #ifdeffery.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

With {read,write}q_relaxed now able to fall back to the common
nonatomic-hi-lo helper, make use of that so that we don't have to
open-code our own. In the process, also convert the other remaining
split accesses, and repurpose the custom accessor to smooth out the
couple of troublesome instances where we really want to avoid
nonatomic writes (and a 64-bit access is unnecessary in the 32-bit
context formats we would use on a 32-bit CPU).

This paves the way for getting rid of some of the assumptions currently
baked into the driver which make it really awkward to use 32-bit context
formats with SMMUv2 under a 64-bit kernel.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

MMU-500 erratum #841119 is tickled by a particular set of circumstances
interacting with the next-page prefetcher. Since said prefetcher is
quite dumb and actually detrimental to performance in some cases (by
causing unwanted TLB evictions for non-sequential access patterns), we
lose very little by turning it off, and what we gain is a guarantee that
the erratum is never hit.

As a bonus, the same workaround will also prevent erratum #826419 once
v7 short descriptor support is implemented.

CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

With a framework for implementation-specific funtionality in place, the
currently-FDT-dependent ThunderX workaround gets to be the first user.
Acked-by: NTirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

As the inevitable reality of implementation-specific errata workarounds
begin to accrue alongside our integration quirk handling, it's about
time the driver had a decent way of keeping track. Extend the per-SMMU
data so we can identify specific implementations in an efficient and
firmware-agnostic manner.
Acked-by: NTirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Due to erratum #27704, the CN88xx SMMUv2 implementation supports only
shared ASID and VMID numberspaces.

This patch ensures that ASID and VMIDs are unique across all SMMU
instances on affected Cavium systems.
Signed-off-by: NTirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
Signed-off-by: NAkula Geethasowjanya <Geethasowjanya.Akula@caviumnetworks.com>
[will: commit message, comments and formatting]
Signed-off-by: NWill Deacon <will.deacon@arm.com>

This patch adds support for 16-bit VMIDs on implementations of SMMUv2
that support it.
Signed-off-by: NTirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
[will: commit messsage and comments]
Signed-off-by: NWill Deacon <will.deacon@arm.com>

They will be needed there later.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Use the better 'var < 0' check.

Fixes: 7aba6cb9 ('iommu/amd: Make call-sites of get_device_id aware of its return value')
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Until we get fully plumbed into of_iommu_configure, our default
IOMMU_DOMAIN_DMA domains just bypass translation. Since we achieve that
by leaving the stream table entries set to bypass instead of pointing at
a translation context, the context bank we allocate for the domain is
completely wasted. Context banks are typically a rather limited
resource, so don't hog ones we don't need.
Reported-by: NEric Auger <eric.auger@linaro.org>
Tested-by: NEric Auger <eric.auger@linaro.org>
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Commit cbf8277e ("iommu/arm-smmu: Treat IOMMU_DOMAIN_DMA as bypass
for now") ignores requests to attach a device to the default domain
since, without IOMMU-basked DMA ops available everywhere, the default
domain will just lead to unexpected transaction faults being reported.

Unfortunately, the way this was implemented on SMMUv2 causes a
regression with VFIO PCI device passthrough under KVM on AMD Seattle.
On this system, the host controller device is associated with both a
pci_dev *and* a platform_device, and can therefore end up with duplicate
SMR entries, resulting in a stream-match conflict at runtime.

This patch amends the original fix so that attaching to IOMMU_DOMAIN_DMA
is rejected even before configuring the SMRs. This restores the old
behaviour for now, but we'll need to look at handing host controllers
specially when we come to supporting the default domain fully.
Reported-by: NEric Auger <eric.auger@linaro.org>
Tested-by: NEric Auger <eric.auger@linaro.org>
Tested-by: NYang Shi <yang.shi@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Commit 9257b4a2 ('iommu/iova: introduce per-cpu caching to iova allocation')
introduced per-CPU IOVA caches to massively improve scalability. Use them.
Signed-off-by: NOmer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased, cleaned up and reworded the commit message]
Signed-off-by: NAdam Morrison <mad@cs.technion.ac.il>
Reviewed-by: NShaohua Li <shli@fb.com>
Reviewed-by: NBen Serebrin <serebrin@google.com>
[dwmw2: split out VT-d part into a separate patch]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

IOVA allocation has two problems that impede high-throughput I/O.
First, it can do a linear search over the allocated IOVA ranges.
Second, the rbtree spinlock that serializes IOVA allocations becomes
contended.

Address these problems by creating an API for caching allocated IOVA
ranges, so that the IOVA allocator isn't accessed frequently.  This
patch adds a per-CPU cache, from which CPUs can alloc/free IOVAs
without taking the rbtree spinlock.  The per-CPU caches are backed by
a global cache, to avoid invoking the (linear-time) IOVA allocator
without needing to make the per-CPU cache size excessive.  This design
is based on magazines, as described in "Magazines and Vmem: Extending
the Slab Allocator to Many CPUs and Arbitrary Resources" (currently
available at https://www.usenix.org/legacy/event/usenix01/bonwick.html)

Adding caching on top of the existing rbtree allocator maintains the
property that IOVAs are densely packed in the IO virtual address space,
which is important for keeping IOMMU page table usage low.

To keep the cache size reasonable, we bound the IOVA space a CPU can
cache by 32 MiB (we cache a bounded number of IOVA ranges, and only
ranges of size <= 128 KiB).  The shared global cache is bounded at
4 MiB of IOVA space.
Signed-off-by: NOmer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased, cleaned up and reworded the commit message]
Signed-off-by: NAdam Morrison <mad@cs.technion.ac.il>
Reviewed-by: NShaohua Li <shli@fb.com>
Reviewed-by: NBen Serebrin <serebrin@google.com>
[dwmw2: split out VT-d part into a separate patch]
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Make intel-iommu map/unmap/invalidate work with IOVA pfns instead of
pointers to "struct iova". This avoids using the iova struct from the IOVA
red-black tree and the resulting explicit find_iova() on unmap.

This patch will allow us to cache IOVAs in the next patch, in order to
avoid rbtree operations for the majority of map/unmap operations.

Note: In eliminating the find_iova() operation, we have also eliminated
the sanity check previously done in the unmap flow. Arguably, this was
overhead that is better avoided in production code, but it could be
brought back as a debug option for driver development.
Signed-off-by: NOmer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased, fixed to not break iova api, and reworded
 the commit message]
Signed-off-by: NAdam Morrison <mad@cs.technion.ac.il>
Reviewed-by: NShaohua Li <shli@fb.com>
Reviewed-by: NBen Serebrin <serebrin@google.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch avoids taking the device_domain_lock in iommu_flush_dev_iotlb()
for domains with no dev iotlb devices.
Signed-off-by: NOmer Peleg <omer@cs.technion.ac.il>
[gvdl@google.com: fixed locking issues]
Signed-off-by: NGodfrey van der Linden <gvdl@google.com>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: NAdam Morrison <mad@cs.technion.ac.il>
Reviewed-by: NShaohua Li <shli@fb.com>
Reviewed-by: NBen Serebrin <serebrin@google.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Current unmap implementation unmaps the entire area covered by the IOVA
range, which is a power-of-2 aligned region. The corresponding map,
however, only maps those pages originally mapped by the user. This
discrepancy can lead to unmapping of already unmapped entries, which is
unneeded work.

With this patch, only mapped pages are unmapped. This is also a baseline
for a map/unmap implementation based on IOVAs and not iova structures,
which will allow caching.
Signed-off-by: NOmer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: NAdam Morrison <mad@cs.technion.ac.il>
Reviewed-by: NShaohua Li <shli@fb.com>
Reviewed-by: NBen Serebrin <serebrin@google.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Change flush_unmaps() to correctly pass iommu_flush_iotlb_psi()
dma addresses.  (x86_64 mm and dma have the same size for pages
at the moment, but this usage improves consistency.)
Signed-off-by: NOmer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: NAdam Morrison <mad@cs.technion.ac.il>
Reviewed-by: NShaohua Li <shli@fb.com>
Reviewed-by: NBen Serebrin <serebrin@google.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>