Tracepoints that are defined take up around 5K each, even if they are not
used. If they are defined and not used, then they waste memory for unused
code. Soon unused tracepoints will cause warnings.
Remove the unused tracepoints of the cdnsp subsystem. They are:
cdnsp_defered_event
cdnsp_ep0_halted
cdnsp_free_priv_device
cdnsp_handle_cmd_flush_ep
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20250829015650.224063821@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tracepoints that are defined take up around 5K each, even if they are not
used. If they are defined and not used, then they waste memory for unused
code. Soon unused tracepoints will cause warnings.
Remove the unused tracepoints of the cdns3 subsystem. They are:
cdns3_mapped_request
cdns3_map_request
cdns3_stream_transfer_split
cdns3_stream_transfer_split_next_part
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20250829015650.053498355@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tracepoints that are defined take up around 5K each, even if they are not
used. If they are defined and not used, then they waste memory for unused
code. Soon unused tracepoints will cause warnings.
Remove the unused tracepoints of the cdns2 subsystem. They are:
cdns2_ep0_enqueue
cdns2_ep0_set_config
cdns2_ep_queue
cdns2_iso_out_ep_disable
cdns2_lpm
cdns2_mapped_request
cdns2_map_request
cdns2_may_wakeup
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20250829015649.885512884@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the usb251xb assumes i2c control. But from HW point of
view, the hub supports usage case without any i2c, we only want the
gpio controls.
Refactor the code so that register writes for configuration are only
performed if the device has a i2c_client provided and also register as
a platform driver. This allows the driver to be used to manage GPIO
based control of the device.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Link: https://lore.kernel.org/r/20250825234509.1041-4-jszhang@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the modern PM macros for the suspend and resume functions to be
automatically dropped by the compiler when CONFIG_PM or
CONFIG_PM_SLEEP are disabled, without having to use __maybe_unused.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Richard Leitner <richard.leitner@linux.dev>
Link: https://lore.kernel.org/r/20250825234509.1041-3-jszhang@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the usb251xb assumes i2c control, but from HW point of
view, the hub supports usage case without any i2c control, I.E we
only want the gpio controls, for example the following dt node:
usb-hub {
compatible = "microchip,usb2512b";
reset-gpios = <&porta 8 GPIO_ACTIVE_LOW>;
};
Modify the dt-binding of usb2512b to support this usage case, and add
the usage example to the examples section.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250825234509.1041-2-jszhang@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Samsung S3C24xx family of SoCs was removed the Linux kernel in the
commit 61b7f8920b ("ARM: s3c: remove all s3c24xx support"), in January
2023. There are no in-kernel users of remaining S3C24xx compatibles.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250831122222.50332-4-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Samsung S3C24xx family of SoCs was removed the Linux kernel in the
commit 61b7f8920b ("ARM: s3c: remove all s3c24xx support"), in January
2023. There are no in-kernel users of remaining S3C24xx compatibles.
The driver (named s3c2410) is still being used via platform code for
S3C64xx platforms.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20250831122222.50332-3-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Set the hid req->zero flag of ep0/in_ep to true by default,
then the UDC drivers can transfer a zero length packet at
the end if the hid transfer with size divisible to EPs max
packet size according to the USB 2.0 spec.
Signed-off-by: William Wu <william.wu@rock-chips.com>
Link: https://lore.kernel.org/r/1756204087-26111-1-git-send-email-william.wu@rock-chips.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Once the use_os_string flag is set to true for some functions
(e.g. adb/mtp) which need to response the OS string, and then
if we re-bind the ConfigFS gadget to use the other functions
(e.g. hid) which should not to response the OS string, however,
because the use_os_string flag is still true, so the usb gadget
response the OS string descriptor incorrectly, this can cause
the USB device to be unrecognizable on the Windows system.
An example of this as follows:
echo 1 > os_desc/use
ln -s functions/ffs.adb configs/b.1/function0
start adbd
echo "<udc device>" > UDC #succeed
stop adbd
rm configs/b.1/function0
echo 0 > os_desc/use
ln -s functions/hid.gs0 configs/b.1/function0
echo "<udc device>" > UDC #fail to connect on Windows
This patch sets the use_os_string flag to false at bind if
the functions not support OS Descriptors.
Signed-off-by: William Wu <william.wu@rock-chips.com>
Fixes: 87213d388e ("usb: gadget: configfs: OS String support")
Link: https://lore.kernel.org/r/1755833769-25434-1-git-send-email-william.wu@rock-chips.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vbus IRQ is optional, so no error message should be printed if it is
not available.
Signed-off-by: Matthias Schiffer <matthias.schiffer@tq-group.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/20250825124901.2190539-1-alexander.stein@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert the legacy TXT binding for the TWL6030 USB module
to the modern YAML DT schema format. This adds formal validation
and improves documentation using a conditional schema.
The legacy twlxxxx-usb.txt file is no longer needed and is removed.
Signed-off-by: Jihed Chaibi <jihed.chaibi.dev@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250824112338.64953-3-jihed.chaibi.dev@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert the legacy TXT binding for the TWL4030 USB module
to the modern YAML DT schema format. This adds formal validation
and improves documentation using a conditional schema.
Remove the twl4030 section from the obsolete .txt binding file
Signed-off-by: Jihed Chaibi <jihed.chaibi.dev@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250824112338.64953-2-jihed.chaibi.dev@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds device tree bindings for the IXP4xx USB Device
Controller (UDC).
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250820-ixp4xx-udc-bindings-v1-1-640f29140164@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use dwc3_mode_string as the single source of truth for mode-to-string
conversion.
Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20250822092411.173519-2-khtsai@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes to the port capability can be indirectly observed by tracing
register writes to DWC3_GCTL. However, this requires interpreting the
raw value, which is neither intuitive nor precise for debugging.
Monitoring these mode changes is essential for resolving issues related
to USB role switching and enumeration.
Introduce a dedicated trace event to provide a human-readable log when
the port capability is configured.
Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20250822092411.173519-1-khtsai@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the twl6030_usb_probe(), the variable ret is declared as
a u32 type. However, since ret may receive -ENODEV when accepting
the return value of omap_usb2_set_comparator().Therefore, its type
should be changed to int.
Fixes: 0e98de67ba ("usb: otg: make twl6030_usb as a comparator driver to omap_usb2")
Signed-off-by: Xichao Zhao <zhao.xichao@vivo.com>
Link: https://lore.kernel.org/r/20250822092224.30645-1-zhao.xichao@vivo.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Simplify the calculation of 'residue' in rts51x_bulk_transport() and
avoid unnecessarily reassigning 'residue' to itself.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Link: https://lore.kernel.org/r/20250828162623.4840-3-thorsten.blum@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use min_t() to improve usblp_read() and avoid calculating
'avail - usblp->readcount' twice. Use min_t(ssize_t,,) instead of min()
to avoid a signedness error.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Link: https://lore.kernel.org/r/20250829173713.56222-1-thorsten.blum@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xive-specific data is stored in handler_data. This creates a mess, as xive
has to rely on child interrupt controller drivers to clean up this data, as
was done by 9a014f4568 ("powerpc/pseries/pci: Add a msi_free() handler to
clear XIVE data").
Instead, store xive-specific data in chip_data and untangle the child
drivers.
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/83968073022a4cc211dcbd0faccd20ec05e58c3e.1754903590.git.namcao@linutronix.de
Devices with power.no_pm set are not expected to need any power
management at all, so modify device_set_pm_not_required() to set
power.no_callbacks for them too in case runtime PM will be enabled
for any of them (which in principle may be done for convenience if
such a device participates in a dependency chain).
Since device_set_pm_not_required() must be called before device_add()
or it would not have any effect, it can update power.no_callbacks
without locking, unlike pm_runtime_no_callbacks() that can be called
after registering the target device.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable <stable@kernel.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/1950054.tdWV9SEqCh@rafael.j.wysocki
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since faux devices are not supposed to be involved in any kind of
power management, set the no_pm flag for all of them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable <stable@kernel.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/6206518.lOV4Wx5bFT@rafael.j.wysocki
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove hard-coded strings by using the str_write_read() helper function
and silence the following Coccinelle/coccicheck warning reported by
string_choices.cocci:
opportunity for str_write_read(write)
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250819165829.714344-2-thorsten.blum@linux.dev
Alice Ryhl <aliceryhl@google.com> says:
This series adds support for the `struct iov_iter` type. This type
represents an IO buffer for reading or writing, and can be configured
for either direction of communication.
In Rust, we define separate types for reading and writing. This will
ensure that you cannot mix them up and e.g. call copy_from_iter in a
read_iter syscall.
To use the new abstractions, miscdevices are given new methods read_iter
and write_iter that can be used to implement the read/write syscalls on
a miscdevice. The miscdevice sample is updated to provide read/write
operations.
Intended for Greg's miscdevice tree.
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-0-6ce4819c2977@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A userland application can now operate on the char device with read() in
order to consume a locally held buffer. Memory for the buffer is to be
provisioned and the buffer populated in its subsequently provided
write() counterpart.
Signed-off-by: Lee Jones <lee@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-5-6ce4819c2977@google.com
These will be used for the read_iter() and write_iter() callbacks, which
are now the preferred back-ends for when a user operates on a char device
with read() and write() respectively.
Co-developed-by: Lee Jones <lee@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-4-6ce4819c2977@google.com
This adds a very simple Kiocb struct that lets you access the inner
file's private data and the file position. For now, nothing else is
supported.
Cc: Christian Brauner <brauner@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-3-6ce4819c2977@google.com
This adds abstractions for the iov_iter type in the case where
data_source is ITER_DEST. This will make Rust implementations of
fops->read_iter possible.
This series only has support for using existing IO vectors created by C
code. Additional abstractions will be needed to support the creation of
IO vectors in Rust code.
These abstractions make the assumption that `struct iov_iter` does not
have internal self-references, which implies that it is valid to move it
between different local variables.
This patch adds an IovIterDest struct that is very similar to the
IovIterSource from the previous patch. However, as the methods on the
two structs have very little overlap (just getting the length and
advance/revert), I do not think it is worth it to try and deduplicate
this logic.
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-2-6ce4819c2977@google.com
This adds abstractions for the iov_iter type in the case where
data_source is ITER_SOURCE. This will make Rust implementations of
fops->write_iter possible.
This series only has support for using existing IO vectors created by C
code. Additional abstractions will be needed to support the creation of
IO vectors in Rust code.
These abstractions make the assumption that `struct iov_iter` does not
have internal self-references, which implies that it is valid to move it
between different local variables.
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250822-iov-iter-v5-1-6ce4819c2977@google.com
Now that we have pci::Device::unbind() we can unregister the sysmem
flush page with a direct access the I/O resource, i.e. without RCU read
side critical section.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://lore.kernel.org/r/20250901150207.63094-1-dakr@kernel.org
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Remove legacy-of-mm-gpiochip.h header file. The above mentioned
file provides an OF API that's deprecated. There is no agnostic
alternatives to it and we have to open code the logic which was
hidden behind of_mm_gpiochip_add_data(). Note, most of the GPIO
drivers are using their own labeling schemas and resource retrieval
that only a few may gain of the code deduplication, so whenever
alternative is appear we can move drivers again to use that one.
[text copied from commit 34064c8267 ("powerpc/8xx:
Drop legacy-of-mm-gpiochip.h header")]
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/9652736ef05b94d9113ea5ce7899734ef82343d1.1755520794.git.christophe.leroy@csgroup.eu
Remove legacy-of-mm-gpiochip.h header file. The above mentioned
file provides an OF API that's deprecated. There is no agnostic
alternatives to it and we have to open code the logic which was
hidden behind of_mm_gpiochip_add_data(). Note, most of the GPIO
drivers are using their own labeling schemas and resource retrieval
that only a few may gain of the code deduplication, so whenever
alternative is appear we can move drivers again to use that one.
As a side effect this change fixes a potential memory leak on
an error path, if of_mm_gpiochip_add_data() fails.
[Text copied from commit 34064c8267 ("powerpc/8xx: Drop
legacy-of-mm-gpiochip.h header")]
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/2f8f16eac72b9ec202b6e593939b44308891a661.1755519343.git.christophe.leroy@csgroup.eu
Remove legacy-of-mm-gpiochip.h header file. The above mentioned
file provides an OF API that's deprecated. There is no agnostic
alternatives to it and we have to open code the logic which was
hidden behind of_mm_gpiochip_add_data(). Note, most of the GPIO
drivers are using their own labeling schemas and resource retrieval
that only a few may gain of the code deduplication, so whenever
alternative is appear we can move drivers again to use that one.
As a side effect this change fixes a potential memory leak on
an error path, if of_mm_gpiochip_add_data() fails.
[text copied from commit 34064c8267 ("powerpc/8xx:
Drop legacy-of-mm-gpiochip.h header")]
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/2662f24c539db393f11b27f0feae2dc14bb2f08f.1755518891.git.christophe.leroy@csgroup.eu
SPRN_M_TWB contains the address of task PGD minus an offset which
compensates the offset required when accessing the kernel PGDIR.
However, since commit ac9f97ff8b ("powerpc/8xx: Inconditionally use
task PGDIR in DTLB misses") and commit 33c527522f ("powerpc/8xx:
Inconditionally use task PGDIR in ITLB misses") kernel PGDIR is not
used anymore in hot paths.
Remove this offset which was added by
commit fde5a9057f ("powerpc/8xx: Optimise access to swapper_pg_dir")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[maddy: Fixed checkpatch.pl warning for "pathes"]
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/9710d960b512996e64beebfd368cfeaadb28b3ba.1755509047.git.christophe.leroy@csgroup.eu
powerpc supports BPF atomic operations using a loop around
Load-And-Reserve(LDARX/LWARX) and Store-Conditional(STDCX/STWCX)
instructions gated by sync instructions to enforce full ordering.
To implement arena_atomics, arena vm start address is added to the
dst_reg to be used for both the LDARX/LWARX and STDCX/STWCX instructions.
Further, an exception table entry is added for LDARX/LWARX
instruction to land after the loop on fault. At the end of sequence,
dst_reg is restored by subtracting arena vm start address.
bpf_jit_supports_insn() is introduced to selectively enable instruction
support as in other architectures like x86 and arm64.
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Saket Kumar Bhaskar <skb99@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250904100835.1100423-5-skb99@linux.ibm.com
The existing code for emitting bpf atomic instruction sequences for
atomic operations such as XCHG, CMPXCHG, ADD, AND, OR, and XOR has been
refactored into a reusable function, bpf_jit_emit_ppc_atomic_op().
It also computes the jump offset and tracks the instruction index for jited
LDARX/LWARX to be used in case it causes a fault.
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Saket Kumar Bhaskar <skb99@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250904100835.1100423-4-skb99@linux.ibm.com
LLVM generates bpf_addr_space_cast instruction while translating
pointers between native (zero) address space and
__attribute__((address_space(N))). The addr_space=0 is reserved as
bpf_arena address space.
rY = addr_space_cast(rX, 0, 1) is processed by the verifier and
converted to normal 32-bit move: wX = wY.
rY = addr_space_cast(rX, 1, 0) : used to convert a bpf arena pointer to
a pointer in the userspace vma. This has to be converted by the JIT.
PPC_RAW_RLDICL_DOT, a variant of PPC_RAW_RLDICL is introduced to set
condition register as well.
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Saket Kumar Bhaskar <skb99@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250904100835.1100423-3-skb99@linux.ibm.com
Add support for [LDX | STX | ST], PROBE_MEM32, [B | H | W | DW]
instructions. They are similar to PROBE_MEM instructions with the
following differences:
- PROBE_MEM32 supports store.
- PROBE_MEM32 relies on the verifier to clear upper 32-bit of the
src/dst register
- PROBE_MEM32 adds 64-bit kern_vm_start address (which is stored in _R26
in the prologue). Due to bpf_arena constructions such _R26 + reg +
off16 access is guaranteed to be within arena virtual range, so no
address check at run-time.
- PROBE_MEM32 allows STX and ST. If they fault the store is a nop. When
LDX faults the destination register is zeroed.
To support these on powerpc, we do tmp1 = _R26 + src/dst reg and then use
tmp1 as the new src/dst register. This allows us to reuse most of the
code for normal [LDX | STX | ST].
Additionally, bpf_jit_emit_probe_mem_store() is introduced to emit
instructions for storing memory values depending on the size (byte,
halfword, word, doubleword).
Stack layout is adjusted to introduce a new NVR (_R26) and to make
BPF_PPC_STACKFRAME quadword aligned (local_tmp_var is increased by
8 bytes).
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Saket Kumar Bhaskar <skb99@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250904100835.1100423-2-skb99@linux.ibm.com
Redundant data is used to enhance data fault tolerance, and the storage
method for redundant data vary depending on the RAID levels. And it's
important to maintain the consistency of redundant data.
Bitmap is used to record which data blocks have been synchronized and which
ones need to be resynchronized or recovered. Each bit in the bitmap
represents a segment of data in the array. When a bit is set, it indicates
that the multiple redundant copies of that data segment may not be
consistent. Data synchronization can be performed based on the bitmap after
power failure or readding a disk. If there is no bitmap, a full disk
synchronization is required.
Due to known performance issues with md-bitmap and the unreasonable
implementations:
- self-managed IO submitting like filemap_write_page();
- global spin_lock
I have decided not to continue optimizing based on the current bitmap
implementation, this new bitmap is invented without locking from IO fast
path and can be used with fast disks.
For designs and details, see the comments in drivers/md-llbitmap.c.
Link: https://lore.kernel.org/linux-raid/20250829080426.1441678-12-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Li Nan <linan122@huawei.com>
daemon_work() will be called by daemon thread, on the one hand, daemon
thread doesn't have strict wake-up time; on the other hand, too much
work are put to daemon thread, like handle sync IO, handle failed
or specail normal IO, handle recovery, and so on. Hence daemon thread
may be too busy to clear dirty bits in time.
Make bitmap_ops->daemon_work() optional and following patches will use
separate async work to clear dirty bits for the new bitmap.
Link: https://lore.kernel.org/linux-raid/20250829080426.1441678-11-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Li Nan <linan122@huawei.com>
