The original architecture of /sys/bus/dsa invented a scheme whereby
a single entry in the list of bus drivers, /sys/bus/drivers/dsa,
handled all device types and internally routed them to different
different drivers. Those internal drivers were invisible to
userspace.

With the idxd driver transitioned to a proper bus device-driver model,
the legacy behavior needs to be preserved due to it being exposed to
user space via sysfs. Create a compat driver to provide the legacy
behavior for /sys/bus/dsa/drivers/dsa. This should satisfy user
tool accel-config v3.2 or ealier where this behavior is expected.
If the distro has a newer accel-config then the legacy mode does
not need to be enabled.

When the compat driver binds the device (i.e. dsa0) to the dsa driver,
it will be bound to the new idxd_drv. The wq device (i.e. wq0.0) will
be bound to either the dmaengine_drv or the user_drv. The dsa_drv
becomes a routing mechansim for the new drivers. It will not support
additional external drivers that are implemented later.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

In preparation for dsa_drv compat support to be built-in, move the bus
code to its own compilation unit. A follow-on patch adds the compat
implementation. Recall that the compat implementation allows for the
deprecated / omnibus dsa_drv binding scheme rather than the idiomatic
organization of a full fledged bus driver per driver type.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

The original architecture of /sys/bus/dsa invented a scheme whereby a
single entry in the list of bus drivers, /sys/bus/drivers/dsa, handled
all device types and internally routed them to different drivers.
Those internal drivers were invisible to userspace. Now, as
/sys/bus/dsa wants to grow support for alternate drivers for a given
device, for example vfio-mdev instead of kernel-internal-dmaengine, a
proper bus device-driver model is needed. The first step in that process
is separating the existing omnibus/implicit "dsa" driver into proper
individual drivers registered on /sys/bus/dsa. Establish the
idxd_user_drv driver that controls the enabling and disabling of the
wq and also register and unregister a char device to allow user space
to mmap the descriptor submission portal.

The cdev related bits are moved to the cdev driver probe/remove and out of
the drv_enabe/disable_wq() calls. These bits are exclusive to the cdev
operation and not part of the generic enable/disable of the wq device.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

The original architecture of /sys/bus/dsa invented a scheme whereby a
single entry in the list of bus drivers, /sys/bus/drivers/dsa, handled
all device types and internally routed them to different drivers.
Those internal drivers were invisible to userspace. Now, as
/sys/bus/dsa wants to grow support for alternate drivers for a given
device, for example vfio-mdev instead of kernel-internal-dmaengine, a
proper bus device-driver model is needed. The first step in that process
is separating the existing omnibus/implicit "dsa" driver into proper
individual drivers registered on /sys/bus/dsa. Establish the
idxd_dmaengine_drv driver that controls the enabling and disabling of the
wq and also register and unregister the dma channel.

idxd_wq_alloc_resources() and idxd_wq_free_resources() also get moved to
the dmaengine driver. The resources (dma descriptors allocation and setup)
are only used by the dmaengine driver and should only happen when it loads.

The char dev driver (cdev) related bits are left in the __drv_enable_wq()
and __drv_disable_wq() calls to be moved when we split out the char dev
driver just like how the dmaengine driver is split out.

WQ autoload support is not expected currently. With the amount of
configuration needed for the device, the wq is always expected to
be enabled by a tool (or via sysfs) rather than auto enabled at driver
load.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

The original architecture of /sys/bus/dsa invented a scheme whereby a
single entry in the list of bus drivers, /sys/bus/drivers/dsa, handled
all device types and internally routed them to different drivers.
Those internal drivers were invisible to userspace. Now, as
/sys/bus/dsa wants to grow support for alternate drivers for a given
device, for example vfio-mdev instead of kernel-internal-dmaengine, a
proper bus device-driver model is needed. The first step in that process
is separating the existing omnibus/implicit "dsa" driver into proper
individual drivers registered on /sys/bus/dsa. Establish the idxd_drv
driver that control the enabling and disabling of the accelerator device.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Add an array of support device types to the idxd_device_driver
definition in order to enable simple matching of device type to a
given driver. The deprecated / omnibus dsa_drv driver specifies
IDXD_DEV_NONE as its only role is to service legacy userspace (old
accel-config) directed bind requests and route them to them the proper
driver. It need not attach to a device when the bus is autoprobed. The
accel-config tooling is being updated to drop its dependency on this
deprecated bind scheme.

Reviewed-by: Dan Willliams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Don't need a wrapper to register the driver. Just do it directly.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

… device.c

Move the code related to a ->remove() function for the idxd
'struct device' to device.c to prep for the idxd device
sub-driver in device.c.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Move the code related to a ->probe() function for the idxd
'struct device' to device.c to prep for the idxd device
sub-driver in device.c.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Current implementation have put all the code that should be in a driver
probe/remove in the bus probe/remove function. Add ->probe() and ->remove()
support for the dsa_drv and move all those code out of bus probe/remove.
The change does not split out the distinction between device sub-driver and
wq sub-driver. It only cleans up the bus calls. The split out will be
addressed in follow on patches.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Remove unused iax_bus_type prototype declaration. Should have been removed
when iax_bus_type was removed.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Remove ->shutdown() function for the dsa bus as it does not do anything and
is not necessary.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Move the wq_disable() function to device.c in preparation of setting up the
idxd internal sub-driver framework. No logic changes.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Move the wq_enable() function to device.c in preparation of setting up the
idxd internal sub-driver framework. No logic changes.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

The IDXD_DEV_CONF_READY state flag is no longer needed. The current
implementation uses this flag to stop the device from doing
configuration until the pci driver probe has completed. With the
driver architecture going towards multiple sub-driver attached to
the dsa_bus, this is no longer feasible. The sub-drivers will be
allowed to probe and return with failure when they are not ready
to complete the probe rather than using a state flag to gate the
probing.

There is no expectation that the devices auto-attach to a driver.
Userspace configuration is expected to setup the device before
enabling.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Add a 'struct idxd_dev' that wraps the 'struct device' for idxd conf_dev
that registers with the dsa bus. This is introduced in order to deal with
multiple different types of 'devices' that are registered on the dsa_bus
when the compat driver needs to route them to the correct driver to attach.
The bind() call now can determine the type of device and then do the
appropriate driver matching.

Reviewed-by Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Add name field in idxd_device_driver so we don't have to touch the
'struct device_driver' during declaration.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Add helper functions for dsa-driver registration similar to other
bus-types. In particular, do not require dsa-drivers to open-code the
bus, owner, and mod_name fields. Let registration and unregistration
operate on the 'struct idxd_device_driver' instead of the raw /
embedded 'struct device_driver'.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Now that UML has PCI support, this driver must depend also on
!UML since it pokes at X86_64 architecture internals that don't
exist on ARCH=um.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://lore.kernel.org/r/20210625103810.fe877ae0aef4.If240438e3f50ae226f3f755fc46ea498c6858393@changeid
Signed-off-by: Vinod Koul <vkoul@kernel.org>

IOPS increased when changing MSIX vector to per WQ from roundrobin.
Allows descriptor to be completed by the submitter improves caching
locality.

Suggested-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Link: https://lore.kernel.org/r/162456717326.1130457.15258077196523268356.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

When enqcmds() fails, exit path is missing a percpu_ref_put(). This can
cause failure on shutdown path when the driver is attempting to quiesce the
wq. Add missing percpu_ref_put() call on the error exit path.

Fixes: 93a40a6 ("dmaengine: idxd: add percpu_ref to descriptor submission path")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162456170168.1121236.7240941044089212312.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

The cached command status is only set when the write back status is
is passed in. Move the variable set outside of the check so it is
always set.

Fixes: 0d5c10b ("dmaengine: idxd: add work queue drain support")
Reported-by: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162274329740.1822314.3443875665504707588.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Add occupancy information to wq sysfs attribute. Attribute will show
wq occupancy data if "WQ Occupancy Support" field in WQCAP is 1. It
displays the number of entries currently in this WQ. This is provided
as an estimate and should not be relied on to determine whether there
is space in the WQ. The data is to provide information to user apps
for flow control.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162275745546.1857062.8765615879420582018.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

The previous state cleanup patch only performed wq state cleanups. This
does not go far enough as when device is disabled or reset, the state
for groups and engines must also be cleaned up. Add additional state
cleanup beyond wq cleanup. Tie those cleanups directly to device
disable and reset, and wq disable and reset.

Fixes: da32b28 ("dmaengine: idxd: cleanup workqueue config after disabling")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162285154108.2096632.5572805472362321307.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

The wrappers in include/linux/pci-dma-compat.h should go away.

Replace 'pci_set_dma_mask/pci_set_consistent_dma_mask' by an equivalent
and less verbose 'dma_set_mask_and_coherent()' call.

Even if the code may look different, it should have exactly the same
run-time behavior.
If pci_set_dma_mask(64) fails and pci_set_dma_mask(32) succeeds, then
pci_set_consistent_dma_mask(64) will also fail.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/70c8a3bc67e41c5fefb526ecd64c5174c1e2dc76.1625720835.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Intel Elkhart Lake PSE DMA implementation is integrated with crossbar IP
in order to serve more hardware than there are DMA request lines available.

Due to this, program xBAR hardware to make flexible support of PSE peripheral.

The Device-to-Device has not been tested and it's not supported by DMA Engine,
but it's left in the code for the sake of documenting hardware features.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210712113940.42753-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

I know nothing about zone_device pages and !device_private pages; but if
try_to_migrate_one() will do nothing for them, then it's better that
try_to_migrate() filter them first, than trawl through all their vmas.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://lore.kernel.org/lkml/1241d356-8ec9-f47b-a5ec-9b2bf66d242@google.com/
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In the unlikely race case that page_mlock_one() finds VM_LOCKED has been
cleared by the time it got page table lock, page_vma_mapped_walk_done()
must be called before returning, either explicitly, or by a final call
to page_vma_mapped_walk() - otherwise the page table remains locked.

Fixes: cd62734 ("mm/rmap: split try_to_munlock from try_to_unmap")
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Link: https://lore.kernel.org/lkml/20210711151446.GB4070@xsang-OptiPlex-9020/
Link: https://lore.kernel.org/lkml/f71f8523-cba7-3342-40a7-114abc5d1f51@google.com/
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The kernel recovers in due course from missing Mlocked pages: but there
was no point in calling page_mlock() (formerly known as
try_to_munlock()) on a THP, because nothing got done even when it was
found to be mapped in another VM_LOCKED vma.

It's true that we need to be careful: Mlocked accounting of pte-mapped
THPs is too difficult (so consistently avoided); but Mlocked accounting
of only-pmd-mapped THPs is supposed to work, even when multiple mappings
are mlocked and munlocked or munmapped.  Refine the tests.

There is already a VM_BUG_ON_PAGE(PageDoubleMap) in page_mlock(), so
page_mlock_one() does not even have to worry about that complication.

(I said the kernel recovers: but would page reclaim be likely to split
THP before rediscovering that it's VM_LOCKED? I've not followed that up)

Fixes: 9a73f61 ("thp, mlock: do not mlock PTE-mapped file huge pages")
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lore.kernel.org/lkml/cfa154c-d595-406-eb7d-eb9df730f944@google.com/
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Parallel developments in mm/rmap.c have left behind some out-of-date
comments: try_to_migrate_one() also accepts TTU_SYNC (already commented
in try_to_migrate() itself), and try_to_migrate() returns nothing at
all.

TTU_SPLIT_FREEZE has just been deleted, so reword the comment about it
in mm/huge_memory.c; and TTU_IGNORE_ACCESS was removed in 5.11, so
delete the "recently referenced" comment from try_to_unmap_one() (once
upon a time the comment was near the removed codeblock, but they drifted
apart).

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://lore.kernel.org/lkml/563ce5b2-7a44-5b4d-1dfd-59a0e65932a9@google.com/
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

…ux/kernel/git/tip/tip

Pull irq fixes from Ingo Molnar:
 "Two fixes:

   - Fix a MIPS IRQ handling RCU bug

   - Remove a DocBook annotation for a parameter that doesn't exist
     anymore"

* tag 'irq-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/mips: Fix RCU violation when using irqdomain lookup on interrupt entry
  genirq/irqdesc: Drop excess kernel-doc entry @lookup

…inux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar:
 "Three fixes:

   - Fix load tracking bug/inconsistency

   - Fix a sporadic CFS bandwidth constraints enforcement bug

   - Fix a uclamp utilization tracking bug for newly woken tasks"

* tag 'sched-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/uclamp: Ignore max aggregation if rq is idle
  sched/fair: Fix CFS bandwidth hrtimer expiry type
  sched/fair: Sync load_sum with load_avg after dequeue

…nux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar:
 "A fix and a hardware-enablement addition:

   - Robustify uncore_snbep's skx_iio_set_mapping()'s error cleanup

   - Add cstate event support for Intel ICELAKE_X and ICELAKE_D"

* tag 'perf-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Clean up error handling path of iio mapping
  perf/x86/cstate: Add ICELAKE_X and ICELAKE_D support

…/linux/kernel/git/tip/tip

Pull locking fixes from Ingo Molnar:

 - Fix a Sparc crash

 - Fix a number of objtool warnings

 - Fix /proc/lockdep output on certain configs

 - Restore a kprobes fail-safe

* tag 'locking-urgent-2021-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/atomic: sparc: Fix arch_cmpxchg64_local()
  kprobe/static_call: Restore missing static_call_text_reserved()
  static_call: Fix static_call_text_reserved() vs __init
  jump_label: Fix jump_label_text_reserved() vs __init
  locking/lockdep: Fix meaningless /proc/lockdep output of lock classes on !CONFIG_PROVE_LOCKING