linux-stable.git/drivers/iommu/intel/debugfs.c, branch linux-6.9.y

iommu/vt-d: Remove unused vcmd interfaces

2023-12-19T13:32:28+00:00

Commit 99b5726b4423 ("iommu: Remove ioasid infrastructure") has removed
ioasid allocation interfaces from the iommu subsystem. As a result, these
vcmd interfaces have become obsolete. Remove them to avoid dead code.

Signed-off-by: Lu Baolu 
Link: https://lore.kernel.org/r/20231116015048.29675-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel

iommu/vt-d: debugfs: Support dumping a specified page table

2023-10-16T07:34:52+00:00

The original debugfs only dumps all page tables without pasid. With
pasid supported, the page table with pasid also needs to be dumped.

This patch supports dumping a specified page table in legacy mode or
scalable mode with or without a specified pasid.

For legacy mode, according to bus number and DEVFN, traverse the root
table and context table to get the pointer of page table in the
context table entry, then dump the specified page table.

For scalable mode, according to bus number, DEVFN and pasid, traverse
the root table, context table, pasid directory and pasid table to get
the pointer of page table in the pasid table entry, then dump the
specified page table..

Examples are as follows:
1) Dump the page table of device "0000:00:1f.0" that only supports
   legacy mode.
   $ sudo cat
   /sys/kernel/debug/iommu/intel/0000:00:1f.0/domain_translation_struct

2) Dump the page table of device "0000:00:0a.0" with PASID "1" that
   supports scalable mode.
   $ sudo cat
   /sys/kernel/debug/iommu/intel/0000:00:0a.0/1/domain_translation_struct

Suggested-by: Kevin Tian 
Signed-off-by: Jingqi Liu 
Link: https://lore.kernel.org/r/20231013135811.73953-4-Jingqi.liu@intel.com
Signed-off-by: Lu Baolu 
Signed-off-by: Joerg Roedel

iommu/vt-d: debugfs: Create/remove debugfs file per {device, pasid}

2023-10-16T07:34:51+00:00

Add a debugfs directory per pair of {device, pasid} if the mappings of
its page table are created and destroyed by the iommu_map/unmap()
interfaces. i.e. /sys/kernel/debug/iommu/intel//.
Create a debugfs file in the directory for users to dump the page
table corresponding to {device, pasid}. e.g.
/sys/kernel/debug/iommu/intel/0000:00:02.0/1/domain_translation_struct.
For the default domain without pasid, it creates a debugfs file in the
debugfs device directory for users to dump its page table. e.g.
/sys/kernel/debug/iommu/intel/0000:00:02.0/domain_translation_struct.

When setting a domain to a PASID of device, create a debugfs file in
the pasid debugfs directory for users to dump the page table of the
specified pasid. Remove the debugfs device directory of the device
when releasing a device. e.g.
/sys/kernel/debug/iommu/intel/0000:00:01.0

Signed-off-by: Jingqi Liu 
Link: https://lore.kernel.org/r/20231013135811.73953-3-Jingqi.liu@intel.com
Signed-off-by: Lu Baolu 
Signed-off-by: Joerg Roedel

iommu/vt-d: debugfs: Dump entry pointing to huge page

2023-10-16T07:34:51+00:00

For the page table entry pointing to a huge page, the data below the
level of the huge page is meaningless and does not need to be dumped.

Signed-off-by: Jingqi Liu 
Link: https://lore.kernel.org/r/20231013135811.73953-2-Jingqi.liu@intel.com
Signed-off-by: Lu Baolu 
Signed-off-by: Joerg Roedel

iommu/vt-d: Replace spin_lock_irqsave() with spin_lock()

2022-07-15T08:21:36+00:00

The iommu->lock is used to protect changes in root/context/pasid tables
and domain ID allocation. There's no use case to change these resources
in any interrupt context. Therefore, it is unnecessary to disable the
interrupts when the spinlock is held. The same thing happens on the
device_domain_lock side, which protects the device domain attachment
information. This replaces spin_lock/unlock_irqsave/irqrestore() calls
with the normal spin_lock/unlock().

Signed-off-by: Lu Baolu 
Reviewed-by: Kevin Tian 
Link: https://lore.kernel.org/r/20220706025524.2904370-6-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel

iommu/vt-d: debugfs: Remove device_domain_lock usage

2022-07-15T08:21:33+00:00

The domain_translation_struct debugfs node is used to dump the DMAR page
tables for the PCI devices. It potentially races with setting domains to
devices. The existing code uses the global spinlock device_domain_lock to
avoid the races.

This removes the use of device_domain_lock outside of iommu.c by replacing
it with the group mutex lock. Using the group mutex lock is cleaner and
more compatible to following cleanups.

Signed-off-by: Lu Baolu 
Reviewed-by: Kevin Tian 
Link: https://lore.kernel.org/r/20220706025524.2904370-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel

iommu/vt-d: Move include/linux/intel-iommu.h under iommu

2022-07-15T08:21:31+00:00

This header file is private to the Intel IOMMU driver. Move it to the
driver folder.

Signed-off-by: Lu Baolu 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Jason Gunthorpe 
Reviewed-by: Steve Wahl 
Link: https://lore.kernel.org/r/20220514014322.2927339-8-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel

iommu/vt-d: Remove DEFER_DEVICE_DOMAIN_INFO

2022-03-04T15:46:30+00:00

Allocate and set the per-device iommu private data during iommu device
probe. This makes the per-device iommu private data always available
during iommu_probe_device() and iommu_release_device(). With this changed,
the dummy DEFER_DEVICE_DOMAIN_INFO pointer could be removed. The wrappers
for getting the private data and domain are also cleaned.

Signed-off-by: Lu Baolu 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/20220214025704.3184654-1-baolu.lu@linux.intel.com
Link: https://lore.kernel.org/r/20220301020159.633356-6-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel

iommu/vt-d: Remove aux-domain related callbacks

2022-02-28T12:25:48+00:00

The aux-domain related callbacks are not called in the tree. Remove them
to avoid dead code.

Signed-off-by: Lu Baolu 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/20220216025249.3459465-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel

iommu/vt-d: Expose latency monitor data through debugfs

2021-06-10T07:06:13+00:00

A debugfs interface /sys/kernel/debug/iommu/intel/dmar_perf_latency is
created to control and show counts of execution time ranges for various
types per DMAR. The interface may help debug any potential performance
issue.

By default, the interface is disabled.

Possible write value of /sys/kernel/debug/iommu/intel/dmar_perf_latency
  0 - disable sampling all latency data
  1 - enable sampling IOTLB invalidation latency data
  2 - enable sampling devTLB invalidation latency data
  3 - enable sampling intr entry cache invalidation latency data
  4 - enable sampling prq handling latency data

Read /sys/kernel/debug/iommu/intel/dmar_perf_latency gives a snapshot
of sampling result of all enabled monitors.

Signed-off-by: Fenghua Yu 
Signed-off-by: Lu Baolu 
Link: https://lore.kernel.org/r/20210520031531.712333-1-baolu.lu@linux.intel.com
Link: https://lore.kernel.org/r/20210610020115.1637656-15-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel