driver core: Introduce device_iter_t for device iterating APIs

There are several for_each APIs which has parameter with type below:
int (*fn)(struct device *dev, void *data)
They iterate over variou

driver core: Introduce device_iter_t for device iterating APIs

There are several for_each APIs which has parameter with type below:
int (*fn)(struct device *dev, void *data)
They iterate over various device lists and call @fn() for each device
with caller provided data @*data, and they usually need to modify @*data.

Give the type an dedicated typedef with advantages shown below:
typedef int (*device_iter_t)(struct device *dev, void *data)

- Shorter API declarations and definitions
- Prevent further for_each APIs from using bad parameter type

So introduce device_iter_t and apply it to various existing APIs below:
bus_for_each_dev()
(class|driver)_for_each_device()
device_for_each_child(_reverse|_reverse_from)().

Reviewed-by: Jonathan Cameron <[email protected]>
Signed-off-by: Zijun Hu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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Revert "driver core: shut down devices asynchronously"

This reverts commit 8064952c65045f05ee2671fe437770e50c151776.

The series is being reverted before -rc1 as there are still reports of
lockups o

Revert "driver core: shut down devices asynchronously"

This reverts commit 8064952c65045f05ee2671fe437770e50c151776.

The series is being reverted before -rc1 as there are still reports of
lockups on shutdown, so it's not quite ready for "prime time."

Reported-by: Andrey Skvortsov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: Christoph Hellwig <[email protected]>
Cc: David Jeffery <[email protected]>
Cc: Keith Busch <[email protected]>
Cc: Laurence Oberman <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Sagi Grimberg <[email protected]>
Cc: Stuart Hayes <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: shut down devices asynchronously

Add code to allow asynchronous shutdown of devices, ensuring that each
device is shut down before its parents & suppliers.

Only devices with drivers th

driver core: shut down devices asynchronously

Add code to allow asynchronous shutdown of devices, ensuring that each
device is shut down before its parents & suppliers.

Only devices with drivers that have async_shutdown_enable enabled will be
shut down asynchronously.

This can dramatically reduce system shutdown/reboot time on systems that
have multiple devices that take many seconds to shut down (like certain
NVMe drives). On one system tested, the shutdown time went from 11 minutes
without this patch to 55 seconds with the patch.

Signed-off-by: Stuart Hayes <[email protected]>
Signed-off-by: David Jeffery <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Sagi Grimberg <[email protected]>
Reviewed-by: Keith Busch <[email protected]>
Tested-by: Keith Busch <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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drivers/base: Introduce device_match_t for device finding APIs

There are several drivers/base APIs for finding a specific device, and
they currently use the following good type for the @match parame

drivers/base: Introduce device_match_t for device finding APIs

There are several drivers/base APIs for finding a specific device, and
they currently use the following good type for the @match parameter:
int (*match)(struct device *dev, const void *data)

Since these operations do not modify the caller-provided @*data, this
type is worthy of a dedicated typedef:
typedef int (*device_match_t)(struct device *dev, const void *data)

Advantages of using device_match_t:
- Shorter API declarations and definitions
- Prevent further APIs from using a bad type for @match

So introduce device_match_t and apply it to the existing
(bus|class|driver|auxiliary)_find_device() APIs.

Signed-off-by: Zijun Hu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: make driver_find_device() take a const *

The function driver_find_device() does not modify the struct
device_driver structure directly, so it is safe to be marked as a
constant pointer

driver core: make driver_find_device() take a const *

The function driver_find_device() does not modify the struct
device_driver structure directly, so it is safe to be marked as a
constant pointer type. As that is fixed up, also change the function
signature on the inline functions that call this, which are:
driver_find_device_by_name()
driver_find_device_by_of_node()
driver_find_device_by_devt()
driver_find_next_device()
driver_find_device_by_acpi_dev()

Cc: "Rafael J. Wysocki" <[email protected]>
Link: https://lore.kernel.org/r/2024070849-broken-front-9eb5@gregkh
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: make driver_[create|remove]_file take a const *

The functions driver_create_file() and driver_remove_file() do not
modify the struct device_driver structure directly, so they are safe t

driver core: make driver_[create|remove]_file take a const *

The functions driver_create_file() and driver_remove_file() do not
modify the struct device_driver structure directly, so they are safe to
be marked as a constant pointer type.

Cc: "Rafael J. Wysocki" <[email protected]>
Link: https://lore.kernel.org/r/2024070844-volley-hatchling-c812@gregkh
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: return bool from driver_probe_done

bool is the most sensible return value for a yes/no return. Also
add __init as this funtion is only called from the early boot code.

Signed-off-by:

driver core: return bool from driver_probe_done

bool is the most sensible return value for a yes/no return. Also
add __init as this funtion is only called from the early boot code.

Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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driver core: driver.h: remove extern from function prototypes

The kernel coding style does not require 'extern' in function prototypes
in .h files, so remove them from include/linux/device/driver.h

driver core: driver.h: remove extern from function prototypes

The kernel coding style does not require 'extern' in function prototypes
in .h files, so remove them from include/linux/device/driver.h as they
are not needed.

Acked-by: Rafael J. Wysocki <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: make the bus_type in struct device_driver constant

The pointer to struct bus_type in struct device_driver should only be
pointing to something that can never change now that the driver

driver core: make the bus_type in struct device_driver constant

The pointer to struct bus_type in struct device_driver should only be
pointing to something that can never change now that the driver core has
fixed up the previously writable fields. So mark it as a constant
pointer to enforce this and move forward with the goal of moving
bus_type into read-only memory.

Cc: "Rafael J. Wysocki" <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: bus: constify driver_find()

The driver_find() function can now take a const * to bus_type, not just
a * so fix that up.

Cc: "Rafael J. Wysocki" <[email protected]>
Link: https://lore.k

driver core: bus: constify driver_find()

The driver_find() function can now take a const * to bus_type, not just
a * so fix that up.

Cc: "Rafael J. Wysocki" <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: Make driver_deferred_probe_timeout a static variable

It is not used outside of its compilation unit, so there's no need to
export this variable.

Signed-off-by: Javier Martinez Canillas

driver core: Make driver_deferred_probe_timeout a static variable

It is not used outside of its compilation unit, so there's no need to
export this variable.

Signed-off-by: Javier Martinez Canillas <[email protected]>
Reviewed-by: Andrew Halaney <[email protected]>
Acked-by: John Stultz <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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Revert "driver core: Delete driver_deferred_probe_check_state()"

This reverts commit 9cbffc7a59561be950ecc675d19a3d2b45202b2b.

There are a few more issues to fix that have been reported in the thre

Revert "driver core: Delete driver_deferred_probe_check_state()"

This reverts commit 9cbffc7a59561be950ecc675d19a3d2b45202b2b.

There are a few more issues to fix that have been reported in the thread
for the original series [1]. We'll need to fix those before this will work.
So, revert it for now.

[1] - https://lore.kernel.org/lkml/[email protected]/

Fixes: 9cbffc7a5956 ("driver core: Delete driver_deferred_probe_check_state()")
Tested-by: Tony Lindgren <[email protected]>
Tested-by: Peng Fan <[email protected]>
Tested-by: Douglas Anderson <[email protected]>
Tested-by: Alexander Stein <[email protected]>
Reviewed-by: Tony Lindgren <[email protected]>
Signed-off-by: Saravana Kannan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: Delete driver_deferred_probe_check_state()

The function is no longer used. So delete it.

Tested-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Saravana Kannan <saravan

driver core: Delete driver_deferred_probe_check_state()

The function is no longer used. So delete it.

Tested-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Saravana Kannan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: Add wait_for_init_devices_probe helper function

Some devices might need to be probed and bound successfully before the
kernel boot sequence can finish and move on to init/userspace. For

driver core: Add wait_for_init_devices_probe helper function

Some devices might need to be probed and bound successfully before the
kernel boot sequence can finish and move on to init/userspace. For
example, a network interface might need to be bound to be able to mount
a NFS rootfs.

With fw_devlink=on by default, some of these devices might be blocked
from probing because they are waiting on a optional supplier that
doesn't have a driver. While fw_devlink will eventually identify such
devices and unblock the probing automatically, it might be too late by
the time it unblocks the probing of devices. For example, the IP4
autoconfig might timeout before fw_devlink unblocks probing of the
network interface.

This function is available to temporarily try and probe all devices that
have a driver even if some of their suppliers haven't been added or
don't have drivers.

The drivers can then decide which of the suppliers are optional vs
mandatory and probe the device if possible. By the time this function
returns, all such "best effort" probes are guaranteed to be completed.
If a device successfully probes in this mode, we delete all fw_devlink
discovered dependencies of that device where the supplier hasn't yet
probed successfully because they have to be optional dependencies.

This also means that some devices that aren't needed for init and could
have waited for their optional supplier to probe (when the supplier's
module is loaded later on) would end up probing prematurely with limited
functionality. So call this function only when boot would fail without
it.

Tested-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Saravana Kannan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver: platform: Add helper for safer setting of driver_override

Several core drivers and buses expect that driver_override is a
dynamically allocated memory thus later they can kfree() it.

Howeve

driver: platform: Add helper for safer setting of driver_override

Several core drivers and buses expect that driver_override is a
dynamically allocated memory thus later they can kfree() it.

However such assumption is not documented, there were in the past and
there are already users setting it to a string literal. This leads to
kfree() of static memory during device release (e.g. in error paths or
during unbind):

kernel BUG at ../mm/slub.c:3960!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
...
(kfree) from [<c058da50>] (platform_device_release+0x88/0xb4)
(platform_device_release) from [<c0585be0>] (device_release+0x2c/0x90)
(device_release) from [<c0a69050>] (kobject_put+0xec/0x20c)
(kobject_put) from [<c0f2f120>] (exynos5_clk_probe+0x154/0x18c)
(exynos5_clk_probe) from [<c058de70>] (platform_drv_probe+0x6c/0xa4)
(platform_drv_probe) from [<c058b7ac>] (really_probe+0x280/0x414)
(really_probe) from [<c058baf4>] (driver_probe_device+0x78/0x1c4)
(driver_probe_device) from [<c0589854>] (bus_for_each_drv+0x74/0xb8)
(bus_for_each_drv) from [<c058b48c>] (__device_attach+0xd4/0x16c)
(__device_attach) from [<c058a638>] (bus_probe_device+0x88/0x90)
(bus_probe_device) from [<c05871fc>] (device_add+0x3dc/0x62c)
(device_add) from [<c075ff10>] (of_platform_device_create_pdata+0x94/0xbc)
(of_platform_device_create_pdata) from [<c07600ec>] (of_platform_bus_create+0x1a8/0x4fc)
(of_platform_bus_create) from [<c0760150>] (of_platform_bus_create+0x20c/0x4fc)
(of_platform_bus_create) from [<c07605f0>] (of_platform_populate+0x84/0x118)
(of_platform_populate) from [<c0f3c964>] (of_platform_default_populate_init+0xa0/0xb8)
(of_platform_default_populate_init) from [<c01031f8>] (do_one_initcall+0x8c/0x404)

Provide a helper which clearly documents the usage of driver_override.
This will allow later to reuse the helper and reduce the amount of
duplicated code.

Convert the platform driver to use a new helper and make the
driver_override field const char (it is not modified by the core).

Reviewed-by: Rafael J. Wysocki <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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treewide: Add missing includes masked by cgroup -> bpf dependency

cgroup.h (therefore swap.h, therefore half of the universe)
includes bpf.h which in turn includes module.h and slab.h.
Since we're a

treewide: Add missing includes masked by cgroup -> bpf dependency

cgroup.h (therefore swap.h, therefore half of the universe)
includes bpf.h which in turn includes module.h and slab.h.
Since we're about to get rid of that dependency we need
to clean things up.

v2: drop the cpu.h include from cacheinfo.h, it's not necessary
and it makes riscv sensitive to ordering of include files.

Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Acked-by: Krzysztof Wilczyński <[email protected]>
Acked-by: Peter Chen <[email protected]>
Acked-by: SeongJae Park <[email protected]>
Acked-by: Jani Nikula <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
Link: https://lore.kernel.org/all/[email protected]/ # v1
Link: https://lore.kernel.org/all/[email protected]/ # cacheinfo discussion
Link: https://lore.kernel.org/bpf/[email protected]

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device.h: Remove bogus "the" in kerneldoc

Remove the bogus word "the" from "...once the it is..." in the
documentation describing the "dev_groups" member of the device_driver
structure.

Signed-off-

device.h: Remove bogus "the" in kerneldoc

Remove the bogus word "the" from "...once the it is..." in the
documentation describing the "dev_groups" member of the device_driver
structure.

Signed-off-by: Geert Uytterhoeven <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: Rename deferred_probe_timeout and make it global

Since other subsystems (like regulator) have similar arbitrary
timeouts for how long they try to resolve driver dependencies,
rename def

driver core: Rename deferred_probe_timeout and make it global

Since other subsystems (like regulator) have similar arbitrary
timeouts for how long they try to resolve driver dependencies,
rename deferred_probe_timeout to driver_deferred_probe_timeout
and set it as global, so it can be shared.

Cc: [email protected]
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Linus Walleij <[email protected]>
Cc: Thierry Reding <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: Liam Girdwood <[email protected]>
Cc: Bjorn Andersson <[email protected]>
Cc: Saravana Kannan <[email protected]>
Cc: Todd Kjos <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Pavel Machek <[email protected]>
Cc: Ulf Hansson <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Rob Herring <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
Reviewed-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: John Stultz <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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driver core: Remove driver_deferred_probe_check_state_continue()

Now that driver_deferred_probe_check_state() works better, and
we've converted the only user of
driver_deferred_probe_check_state_con

driver core: Remove driver_deferred_probe_check_state_continue()

Now that driver_deferred_probe_check_state() works better, and
we've converted the only user of
driver_deferred_probe_check_state_continue() we can simply
remove it and simplify some of the logic.

Cc: [email protected]
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Linus Walleij <[email protected]>
Cc: Thierry Reding <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: Liam Girdwood <[email protected]>
Cc: Bjorn Andersson <[email protected]>
Cc: Saravana Kannan <[email protected]>
Cc: Todd Kjos <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Pavel Machek <[email protected]>
Cc: Ulf Hansson <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Rob Herring <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
Reviewed-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: John Stultz <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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device.h: move 'struct driver' stuff out to device/driver.h

device.h has everything and the kitchen sink when it comes to struct
device things, so split out the struct driver things things to a
sepa

device.h: move 'struct driver' stuff out to device/driver.h

device.h has everything and the kitchen sink when it comes to struct
device things, so split out the struct driver things things to a
separate .h file to make things easier to maintain and manage over time.

Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Suzuki K Poulose <[email protected]>
Cc: Saravana Kannan <[email protected]>
Cc: Heikki Krogerus <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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