The AMD IOMMU XT mode enables interrupt remapping with 32-bit destination
APIC ID, which is required for x2APIC. The feature is available when
the XTSup bit is set in the IOMMU Extended Feature register
and/or the IVHD Type 10h IOMMU Feature Reporting field.

For more information, please see section "IOMMU x2APIC Support" of
the AMD I/O Virtualization Technology (IOMMU) Specification.

Cc: Joerg Roedel <jroedel@suse.de>
Signed-off-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Currently, the driver only supports lower 32-bit of IOMMU Control register.
However, newer AMD IOMMU specification has extended this register
to 64-bit. Therefore, replace the accessing API with the 64-bit version.

Cc: Joerg Roedel <jroedel@suse.de>
Signed-off-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Implement a skeleton framework for debugfs support in the AMD
IOMMU.  Add an AMD-specific Kconfig boolean that depends upon
general enablement of DebugFS in the IOMMU.
Signed-off-by: NGary R Hook <gary.hook@amd.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Several functions in this driver are called from atomic context,
and thus raw locks must be used in order to be safe on PREEMPT_RT.

This includes paths that must wait for command completion, which is
a potential PREEMPT_RT latency concern but not easily avoidable.
Signed-off-by: NScott Wood <swood@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

pci_get_bus_and_slot() is restrictive such that it assumes domain=0 as
where a PCI device is present. This restricts the device drivers to be
reused for other domain numbers.

Getting ready to remove pci_get_bus_and_slot() function in favor of
pci_get_domain_bus_and_slot().

Hard-code the domain number as 0 for the AMD IOMMU driver.
Signed-off-by: NSinan Kaya <okaya@codeaurora.org>
Signed-off-by: NBjorn Helgaas <helgaas@kernel.org>
Reviewed-by: NGary R Hook <gary.hook@amd.com>
Acked-by: NJoerg Roedel <jroedel@suse.de>

pr_err() messages should end with a new-line to avoid other messages
being concatenated. So replace '/n' with '\n'.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Fixes: 45a01c42 ('iommu/amd: Add function copy_dev_tables()')
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The variable amd_iommu_pre_enabled is used in non-init
code-paths, so remove the __initdata annotation.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Fixes: 3ac3e5ee ('iommu/amd: Copy old trans table from old kernel')
Acked-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This was reported by the kbuild bot. The condition in which
entry would be used uninitialized can not happen, because
when there is no iommu this function would never be called.
But its no fast-path, so fix the warning anyway.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Acked-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

It's ok to disable iommu early in normal kernel or in kdump kernel when
amd_iommu=off is specified. While we should not disable it in kdump kernel
when on-flight dma is still on-going.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

When iommu is pre_enabled in kdump kernel, if a device is set up with
guest translations (DTE.GV=1), then don't copy GCR3 table root pointer
but move the device over to an empty guest-cr3 table and handle the
faults in the PPR log (which answer them with INVALID). After all these
PPR faults are recoverable for the device and we should not allow the
device to change old-kernels data when we don't have to.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

AMD pointed out it's unsafe to update the device-table while iommu
is enabled. It turns out that device-table pointer update is split
up into two 32bit writes in the IOMMU hardware. So updating it while
the IOMMU is enabled could have some nasty side effects.

The safe way to work around this is to always allocate the device-table
below 4G, including the old device-table in normal kernel and the
device-table used for copying the content of the old device-table in kdump
kernel. Meanwhile we need check if the address of old device-table is
above 4G because it might has been touched accidentally in corrupted
1st kernel.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Firstly split the dev table entry copy into address translation part
and irq remapping part. Because these two parts could be enabled
independently.

Secondly do sanity check for address translation and irq remap of old
dev table entry separately.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Here several things need be done:
- If iommu is pre-enabled in a normal kernel, just disable it and print
  warning.

- If any one of IOMMUs is not pre-enabled in kdump kernel, just continue
  as it does in normal kernel.

- If failed to copy dev table of old kernel, continue to proceed as
  it does in normal kernel.

- Only if all IOMMUs are pre-enabled and copy dev table is done well, free
  the dev table allocated in early_amd_iommu_init() and make amd_iommu_dev_table
  point to the copied one.

- Disable and Re-enable event/cmd buffer,  install the copied DTE table
  to reg, and detect and enable guest vapic.

- Flush all caches
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Add function copy_dev_tables to copy the old DEV table entries of the panicked
kernel to the new allocated device table. Since all iommus share the same device
table the copy only need be done one time. Here add a new global old_dev_tbl_cpy
to point to the newly allocated device table which the content of old device
table will be copied to. Besides, we also need to:

  - Check whether all IOMMUs actually use the same device table with the same size

  - Verify that the size of the old device table is the expected size.

  - Reserve the old domain id occupied in 1st kernel to avoid touching the old
    io-page tables. Then on-flight DMA can continue looking it up.

And also define MACRO DEV_DOMID_MASK to replace magic number 0xffffULL, it can be
reused in copy_dev_tables().
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This reverts commit 54bd6357.

We still need the IO_PAGE_FAULT message to warn error after the
issue of on-flight dma in kdump kernel is fixed.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Move single iommu enabling codes into a wrapper function early_enable_iommu().
This can make later kdump change easier.

And also add iommu_disable_command_buffer and iommu_disable_event_buffer
for later usage.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Add functions to check whether translation is already enabled in IOMMU.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The register_syscore_ops() function takes a mutex and might
sleep. In the IOMMU initialization code it is invoked during
irq-remapping setup already, where irqs are disabled.

This causes a schedule-while-atomic bug:

 BUG: sleeping function called from invalid context at kernel/locking/mutex.c:747
 in_atomic(): 0, irqs_disabled(): 1, pid: 1, name: swapper/0
 no locks held by swapper/0/1.
 irq event stamp: 304
 hardirqs last  enabled at (303): [<ffffffff818a87b6>] _raw_spin_unlock_irqrestore+0x36/0x60
 hardirqs last disabled at (304): [<ffffffff8235d440>] enable_IR_x2apic+0x79/0x196
 softirqs last  enabled at (36): [<ffffffff818ae75f>] __do_softirq+0x35f/0x4ec
 softirqs last disabled at (31): [<ffffffff810c1955>] irq_exit+0x105/0x120
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-rc2.1.el7a.test.x86_64.debug #1
 Hardware name:          PowerEdge C6145 /040N24, BIOS 3.5.0 10/28/2014
 Call Trace:
  dump_stack+0x85/0xca
  ___might_sleep+0x22a/0x260
  __might_sleep+0x4a/0x80
  __mutex_lock+0x58/0x960
  ? iommu_completion_wait.part.17+0xb5/0x160
  ? register_syscore_ops+0x1d/0x70
  ? iommu_flush_all_caches+0x120/0x150
  mutex_lock_nested+0x1b/0x20
  register_syscore_ops+0x1d/0x70
  state_next+0x119/0x910
  iommu_go_to_state+0x29/0x30
  amd_iommu_enable+0x13/0x23

Fix it by moving the register_syscore_ops() call to the next
initialization step, which runs with irqs enabled.
Reported-by: NArtem Savkov <asavkov@redhat.com>
Tested-by: NArtem Savkov <asavkov@redhat.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Fixes: 2c0ae172 ('iommu/amd: Convert iommu initialization to state machine')
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The IOMMU is programmed with physical addresses for the various tables
and buffers that are used to communicate between the device and the
driver. When the driver allocates this memory it is encrypted. In order
for the IOMMU to access the memory as encrypted the encryption mask needs
to be included in these physical addresses during configuration.

The PTE entries created by the IOMMU should also include the encryption
mask so that when the device behind the IOMMU performs a DMA, the DMA
will be performed to encrypted memory.
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Acked-by: NJoerg Roedel <jroedel@suse.de>
Cc: <iommu@lists.linux-foundation.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/3053631ea25ba8b1601c351cb7c541c496f6d9bc.1500319216.git.thomas.lendacky@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This check needs to happens later now, when all previously
enabled IOMMUs have been disabled.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

After we made sure that all IOMMUs have been disabled we
need to make sure that all resources we allocated are
released again.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Avoid any tries to double-free these pointers.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Check if we are in an error state already before calling
into state_next().
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This will be used when during initialization we detect that
the iommu should be disabled.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The function will also be used to free iommu resources when
amd_iommu=off was specified on the kernel command line. So
rename the function to reflect that.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

When booting, make sure the IOMMUs are disabled. They could
be previously enabled if we boot into a kexec or kdump
kernel. So make sure they are off.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

When booting into a kdump kernel, suppress IO_PAGE_FAULTs by
default for all devices. But allow the faults again when a
domain is assigned to a device.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

As newer, higher speed devices are developed, perf data shows that the
amount of MMIO that is performed when submitting commands to the IOMMU
causes performance issues. Currently, the command submission path reads
the command buffer head and tail pointers and then writes the tail
pointer once the command is ready.

The tail pointer is only ever updated by the driver so it can be tracked
by the driver without having to read it from the hardware.

The head pointer is updated by the hardware, but can be read
opportunistically. Reading the head pointer only when it appears that
there might not be room in the command buffer and then re-checking the
available space reduces the number of times the head pointer has to be
read.
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Currently, amd_iommu_pc_get_set_reg_val() cannot support multiple
IOMMUs. Modify it to allow callers to specify an IOMMU. This is in
preparation for supporting multiple IOMMUs.
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/1487926102-13073-8-git-send-email-Suravee.Suthikulpanit@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently, amd_iommu_pc_get_max_[banks|counters]() use end-point device
ID to locate an IOMMU and check the reported max banks/counters. The
logic assumes that the IOMMU_BASE_DEVID belongs to the first IOMMU, and
uses it to acquire a reference to the first IOMMU, which does not work
on certain systems. Instead, modify the function to take an IOMMU index,
and use it to query the corresponding AMD IOMMU instance.

Currently, hardcode the IOMMU index to 0 since the current AMD IOMMU
perf implementation supports only a single IOMMU. A subsequent patch
will add support for multiple IOMMUs, and will use a proper IOMMU index.
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/1487926102-13073-7-git-send-email-Suravee.Suthikulpanit@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Introduce amd_iommu_get_num_iommus(), which returns the value of
amd_iommus_present. The function is used to replace direct access to the
variable, which is now declared as static.

This function will also be used by AMD IOMMU perf driver.
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/1487926102-13073-6-git-send-email-Suravee.Suthikulpanit@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Clean up coding style and fix a bug in the 64-bit register read logic
since it overwrites the upper 32-bit when reading the lower 32-bit.
Signed-off-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/1487926102-13073-5-git-send-email-Suravee.Suthikulpanit@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The link between the iommu sysfs-device and the struct
amd_iommu is no longer stored as driver-data. Update the
code to the new correct way of getting from device to
amd_iommu.
Reported-by: NDave Jones <davej@codemonkey.org.uk>
Fixes: 39ab9555 ('iommu: Add sysfs bindings for struct iommu_device')
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

There is currently support for iommu sysfs bindings, but
those need to be implemented in the IOMMU drivers. Add a
more generic version of this by adding a struct device to
struct iommu_device and use that for the sysfs bindings.

Also convert the AMD and Intel IOMMU driver to make use of
it.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This struct represents one hardware iommu in the iommu core
code. For now it only has the iommu-ops associated with it,
but that will be extended soon.

The register/unregister interface is also added, as well as
making use of it in the Intel and AMD IOMMU drivers.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Prevent early_amd_iommu_init() from leaking memory mapped via
acpi_get_table() if check_ivrs_checksum() returns an error.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This patch removes the users of the deprectated APIs:
 acpi_get_table_with_size()
 early_acpi_os_unmap_memory()
The following APIs should be used instead of:
 acpi_get_table()
 acpi_put_table()

The deprecated APIs are invented to be a replacement of acpi_get_table()
during the early stage so that the early mapped pointer will not be stored
in ACPICA core and thus the late stage acpi_get_table() won't return a
wrong pointer. The mapping size is returned just because it is required by
early_acpi_os_unmap_memory() to unmap the pointer during early stage.

But as the mapping size equals to the acpi_table_header.length
(see acpi_tb_init_table_descriptor() and acpi_tb_validate_table()), when
such a convenient result is returned, driver code will start to use it
instead of accessing acpi_table_header to obtain the length.

Thus this patch cleans up the drivers by replacing returned table size with
acpi_table_header.length, and should be a no-op.
Reported-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This will get rid of a lot false positives caused by kmemleak being
unaware of the irq_remap_table. Based on a suggestion from Catalin Marinas.
Signed-off-by: NLucas Stach <dev@lynxeye.de>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

It will be more readable and safer than the old setting.
Signed-off-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Introduce struct iommu_dev_data.use_vapic flag, which IOMMU driver
uses to determine if it should enable vAPIC support, by setting
the ga_mode bit in the device's interrupt remapping table entry.

Currently, it is enabled for all pass-through device if vAPIC mode
is enabled.
Signed-off-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>