Ever since the eventfd type was introduced back in 2007 in commit
e1ad7468c7 ("signal/timer/event: eventfd core") the eventfd_signal()
function only ever passed 1 as a value for @n. There's no point in
keeping that additional argument.
Link: https://lore.kernel.org/r/20231122-vfs-eventfd-signal-v2-2-bd549b14ce0c@kernel.org
Acked-by: Xu Yilun <yilun.xu@intel.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com> # ocxl
Acked-by: Eric Farman <farman@linux.ibm.com> # s390
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Now that the driver core allows for struct class to be in read-only
memory, we should make all 'class' structures declared at build time
placing them into read-only memory, instead of having to be dynamically
allocated at runtime.
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Link: https://lore.kernel.org/r/2023102403-squirt-defraud-6c0c@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something. So just remove it and fix up all callers of the function in
the kernel tree at the same time.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the set of driver core and kernfs changes for 6.2-rc1.
The "big" change in here is the addition of a new macro,
container_of_const() that will preserve the "const-ness" of a pointer
passed into it.
The "problem" of the current container_of() macro is that if you pass in
a "const *", out of it can comes a non-const pointer unless you
specifically ask for it. For many usages, we want to preserve the
"const" attribute by using the same call. For a specific example, this
series changes the kobj_to_dev() macro to use it, allowing it to be used
no matter what the const value is. This prevents every subsystem from
having to declare 2 different individual macros (i.e.
kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
the const value at build time, which having 2 macros would not do
either.
The driver for all of this have been discussions with the Rust kernel
developers as to how to properly mark driver core, and kobject, objects
as being "non-mutable". The changes to the kobject and driver core in
this pull request are the result of that, as there are lots of paths
where kobjects and device pointers are not modified at all, so marking
them as "const" allows the compiler to enforce this.
So, a nice side affect of the Rust development effort has been already
to clean up the driver core code to be more obvious about object rules.
All of this has been bike-shedded in quite a lot of detail on lkml with
different names and implementations resulting in the tiny version we
have in here, much better than my original proposal. Lots of subsystem
maintainers have acked the changes as well.
Other than this change, included in here are smaller stuff like:
- kernfs fixes and updates to handle lock contention better
- vmlinux.lds.h fixes and updates
- sysfs and debugfs documentation updates
- device property updates
All of these have been in the linux-next tree for quite a while with no
problems, OTHER than some merge issues with other trees that should be
obvious when you hit them (block tree deletes a driver that this tree
modifies, iommufd tree modifies code that this tree also touches). If
there are merge problems with these trees, please let me know.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the set of driver core and kernfs changes for 6.2-rc1.
The "big" change in here is the addition of a new macro,
container_of_const() that will preserve the "const-ness" of a pointer
passed into it.
The "problem" of the current container_of() macro is that if you pass
in a "const *", out of it can comes a non-const pointer unless you
specifically ask for it. For many usages, we want to preserve the
"const" attribute by using the same call. For a specific example, this
series changes the kobj_to_dev() macro to use it, allowing it to be
used no matter what the const value is. This prevents every subsystem
from having to declare 2 different individual macros (i.e.
kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
the const value at build time, which having 2 macros would not do
either.
The driver for all of this have been discussions with the Rust kernel
developers as to how to properly mark driver core, and kobject,
objects as being "non-mutable". The changes to the kobject and driver
core in this pull request are the result of that, as there are lots of
paths where kobjects and device pointers are not modified at all, so
marking them as "const" allows the compiler to enforce this.
So, a nice side affect of the Rust development effort has been already
to clean up the driver core code to be more obvious about object
rules.
All of this has been bike-shedded in quite a lot of detail on lkml
with different names and implementations resulting in the tiny version
we have in here, much better than my original proposal. Lots of
subsystem maintainers have acked the changes as well.
Other than this change, included in here are smaller stuff like:
- kernfs fixes and updates to handle lock contention better
- vmlinux.lds.h fixes and updates
- sysfs and debugfs documentation updates
- device property updates
All of these have been in the linux-next tree for quite a while with
no problems"
* tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits)
device property: Fix documentation for fwnode_get_next_parent()
firmware_loader: fix up to_fw_sysfs() to preserve const
usb.h: take advantage of container_of_const()
device.h: move kobj_to_dev() to use container_of_const()
container_of: add container_of_const() that preserves const-ness of the pointer
driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion.
driver core: fix up missed scsi/cxlflash class.devnode() conversion.
driver core: fix up some missing class.devnode() conversions.
driver core: make struct class.devnode() take a const *
driver core: make struct class.dev_uevent() take a const *
cacheinfo: Remove of_node_put() for fw_token
device property: Add a blank line in Kconfig of tests
device property: Rename goto label to be more precise
device property: Move PROPERTY_ENTRY_BOOL() a bit down
device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*()
kernfs: fix all kernel-doc warnings and multiple typos
driver core: pass a const * into of_device_uevent()
kobject: kset_uevent_ops: make name() callback take a const *
kobject: kset_uevent_ops: make filter() callback take a const *
kobject: make kobject_namespace take a const *
...
In commit ff62b8e658 ("driver core: make struct class.devnode() take a
const *") the ->devnode callback changed the pointer to be const, but a
few instances of PowerPC drivers were not caught for some reason.
Fix this up by changing the pointers to be const.
Fixes: ff62b8e658 ("driver core: make struct class.devnode() take a const *")
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Frederic Barrat <fbarrat@linux.ibm.com>
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linuxppc-dev@lists.ozlabs.org
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20221128173539.3112234-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If device_register() returns error in ocxl_file_register_afu(),
the name allocated by dev_set_name() need be freed. As comment
of device_register() says, it should use put_device() to give
up the reference in the error path. So fix this by calling
put_device(), then the name can be freed in kobject_cleanup(),
and info is freed in info_release().
Fixes: 75ca758adb ("ocxl: Create a clear delineation between ocxl backend & frontend")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Link: https://lore.kernel.org/r/20221111145929.2429271-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
eventfd_ctx_put need to be called to put the refcount that gotten by
eventfd_ctx_fdget when ocxl_irq_set_handler fails.
Fixes: 0601466146 ("ocxl: move event_fd handling to frontend")
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Link: https://lore.kernel.org/r/20220824082600.36159-1-hbh25y@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
info_release() will be called in device_unregister() when info->dev's
reference count is 0. So there is no need to call ocxl_afu_put() and
kfree() again.
Fix this by adding free_minor() and return to err_unregister error path.
Fixes: 75ca758adb ("ocxl: Create a clear delineation between ocxl backend & frontend")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220418085758.38145-1-hbh25y@gmail.com
Return value from ocxl_context_attach() directly instead
of taking this in another redundant variable.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211215060438.441918-1-chi.minghao@zte.com.cn
mutex lock can be initialized automatically with DEFINE_MUTEX()
rather than explicitly calling mutex_init().
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201224132446.31286-1-zhengyongjun3@huawei.com
If an ocxl device is unbound through sysfs at the same time its AFU is
being opened by a user process, the open code may dereference freed
stuctures, which can lead to kernel oops messages. You'd have to hit a
tiny time window, but it's possible. It's fairly easy to test by
making the time window bigger artificially.
Fix it with a combination of 2 changes:
- when an AFU device is found in the IDR by looking for the device
minor number, we should hold a reference on the device until after
the context is allocated. A reference on the AFU structure is kept
when the context is allocated, so we can release the reference on
the device after the context allocation.
- with the fix above, there's still another even tinier window,
between the time the AFU device is found in the IDR and the
reference on the device is taken. We can fix this one by removing
the IDR entry earlier, when the device setup is removed, instead
of waiting for the 'release' device callback. With proper locking
around the IDR.
Fixes: 75ca758adb ("ocxl: Create a clear delineation between ocxl backend & frontend")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190624144148.32022-1-fbarrat@linux.ibm.com
In case of error, the function eventfd_ctx_fdget() returns ERR_PTR() and
never returns NULL. The NULL test in the return value check should be
replaced with IS_ERR().
This issue was detected by using the Coccinelle software.
Fixes: 0601466146 ("ocxl: move event_fd handling to frontend")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Event_fd is only used in the driver frontend, so it does not
need to exist in the backend code. Relocate it to the frontend
and provide an opaque mechanism for consumers instead.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The use of offsets is required only in the frontend, so alter
the IRQ API to only work with IRQ IDs in the backend.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Most OpenCAPI operations require a valid context, so
exposing these functions to external drivers is necessary.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The OCXL driver contains both frontend code for interacting with userspace,
as well as backend code for interacting with the hardware.
This patch separates the backend code from the frontend so that it can be
used by other device drivers that communicate via OpenCAPI.
Relocate dev, cdev & sysfs files to the frontend code to allow external
drivers to maintain their own devices.
Reference counting on the device in the backend is replaced with kref
counting.
Move file & sysfs layer initialisation from core.c (backend) to
pci.c (frontend).
Create an ocxl_function oriented interface for initing devices &
enumerating AFUs.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The term 'link' is ambiguous (especially when the struct is used for a
list), so rename it for clarity.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add the missing unlock before return from function
afu_ioctl_enable_p9_wait() in the error handling case.
Fixes: e948e06fc6 ("ocxl: Expose the thread_id needed for wait on POWER9")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In order for a userspace AFU driver to call the POWER9 specific
OCXL_IOCTL_ENABLE_P9_WAIT, it needs to verify that it can actually
make that call.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In order to successfully issue as_notify, an AFU needs to know the TID
to notify, which in turn means that this information should be
available in userspace so it can be communicated to the AFU.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Some required information is not exposed to userspace currently (eg. the
PASID), pass this information back, along with other information which
is currently communicated via sysfs, which saves some parsing effort in
userspace.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Fix some issues found by a static checker:
When allocating an AFU interrupt, if the driver cannot copy the output
parameters to userland, the errno value was not set to EFAULT
Remove a (now) useless cast.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
A larger batch of fixes than we'd like. Roughly 1/3 fixes for new code, 1/3
fixes for stable and 1/3 minor things.
There's four commits fixing bugs when using 16GB huge pages on hash, caused by
some of the preparatory changes for pkeys.
Two fixes for bugs in the enhanced IRQ soft masking for local_t, one of which
broke KVM in some circumstances.
Four fixes for Power9. The most bizarre being a bug where futexes stopped
working because a NULL pointer dereference didn't trap during early boot (it
aliased the kernel mapping). A fix for memory hotplug when using the Radix MMU,
and a fix for live migration of guests using the Radix MMU.
Two fixes for hotplug on pseries machines. One where we weren't correctly
updating NUMA info when CPUs are added and removed. And the other fixes
crashes/hangs seen when doing memory hot remove during boot, which is apparently
a thing people do.
Finally a handful of build fixes for obscure configs and other minor fixes.
Thanks to:
Alexey Kardashevskiy, Aneesh Kumar K.V, Balbir Singh, Colin Ian King, Daniel
Henrique Barboza, Florian Weimer, Guenter Roeck, Harish, Laurent Vivier,
Madhavan Srinivasan, Mauricio Faria de Oliveira, Nathan Fontenot, Nicholas
Piggin, Sam Bobroff.
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Merge tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"A larger batch of fixes than we'd like. Roughly 1/3 fixes for new
code, 1/3 fixes for stable and 1/3 minor things.
There's four commits fixing bugs when using 16GB huge pages on hash,
caused by some of the preparatory changes for pkeys.
Two fixes for bugs in the enhanced IRQ soft masking for local_t, one
of which broke KVM in some circumstances.
Four fixes for Power9. The most bizarre being a bug where futexes
stopped working because a NULL pointer dereference didn't trap during
early boot (it aliased the kernel mapping). A fix for memory hotplug
when using the Radix MMU, and a fix for live migration of guests using
the Radix MMU.
Two fixes for hotplug on pseries machines. One where we weren't
correctly updating NUMA info when CPUs are added and removed. And the
other fixes crashes/hangs seen when doing memory hot remove during
boot, which is apparently a thing people do.
Finally a handful of build fixes for obscure configs and other minor
fixes.
Thanks to: Alexey Kardashevskiy, Aneesh Kumar K.V, Balbir Singh, Colin
Ian King, Daniel Henrique Barboza, Florian Weimer, Guenter Roeck,
Harish, Laurent Vivier, Madhavan Srinivasan, Mauricio Faria de
Oliveira, Nathan Fontenot, Nicholas Piggin, Sam Bobroff"
* tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
selftests/powerpc: Fix to use ucontext_t instead of struct ucontext
powerpc/kdump: Fix powernv build break when KEXEC_CORE=n
powerpc/pseries: Fix build break for SPLPAR=n and CPU hotplug
powerpc/mm/hash64: Zero PGD pages on allocation
powerpc/mm/hash64: Store the slot information at the right offset for hugetlb
powerpc/mm/hash64: Allocate larger PMD table if hugetlb config is enabled
powerpc/mm: Fix crashes with 16G huge pages
powerpc/mm: Flush radix process translations when setting MMU type
powerpc/vas: Don't set uses_vas for kernel windows
powerpc/pseries: Enable RAS hotplug events later
powerpc/mm/radix: Split linear mapping on hot-unplug
powerpc/64s/radix: Boot-time NULL pointer protection using a guard-PID
ocxl: fix signed comparison with less than zero
powerpc/64s: Fix may_hard_irq_enable() for PMI soft masking
powerpc/64s: Fix MASKABLE_RELON_EXCEPTION_HV_OOL macro
powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:
for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done
with de-mangling cleanups yet to come.
NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.
The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently the comparison of used < 0 is always false because
uses is a size_t. Fix this by making used a ssize_t type.
Detected by Coccinelle:
drivers/misc/ocxl/file.c:320:6-10: WARNING: Unsigned expression
compared with zero: used < 0
Fixes: 5ef3166e8a ("ocxl: Driver code for 'generic' opencapi devices")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add user APIs through ioctl to allocate, free, and be notified of an
AFU interrupt.
For opencapi, an AFU can trigger an interrupt on the host by sending a
specific command targeting a 64-bit object handle. On POWER9, this is
implemented by mapping a special page in the address space of a
process and a write to that page will trigger an interrupt.
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add an ocxl driver to handle generic opencapi devices. Of course, it's
not meant to be the only opencapi driver, any device is free to
implement its own. But if a host application only needs basic services
like attaching to an opencapi adapter, have translation faults handled
or allocate AFU interrupts, it should suffice.
The AFU config space must follow the opencapi specification and use
the expected vendor/device ID to be seen by the generic driver.
The driver exposes the device AFUs as a char device in /dev/ocxl/
Note that the driver currently doesn't handle memory attached to the
opencapi device.
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
