The new goldfish_pipe code used too much stack space in the
transfer_max_buffers() call. As the function is serialized with a lock,
let's make the buffer static to not use the stack for the large buffer.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Yurii Zubrytskyi <zyy@google.com>
Cc: Jin Qian <jinqian@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a driver code for a redesigned android pipe.
Currently it works for x86 and x64 emulators with the following
performance results:
ADB push to /dev/null,
Ubuntu,
400 MB file,
times are for (1 / 10 / 100) parallel adb commands
x86 adb push: (4.4s / 11.5s / 2m10s) -> (2.8s / 6s / 51s)
x64 adb push: (7s / 15s / (too long, 6m+) -> (2.7s / 6.2s / 52s)
ADB pull and push to /data/ have the same %% of speedup
More importantly, I don't see any signs of slowdowns when
run in parallel with Antutu benchmark, so it is definitely
making much better job at multithreading.
Signed-off-by: Yurii Zubrytskyi <zyy@google.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This interrupt handler is broken in several ways:
- It loops forever when the op code is not decodeable
- It never returns IRQ_HANDLED because the only way to exit the loop
returns IRQ_NONE unconditionally.
The whole concept of this is broken. Creating devices in an interrupt
handler is beyond any point of sanity.
Make it at least behave halfways sane so accidental users do not have to
deal with a hard to debug lockup.
Fixes: e809c22b8f ("goldfish: add the goldfish virtual bus")
Reported-by: Gabriel C <nix.or.die@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Moving from get_user_pages() to get_user_pages_unlocked() simplifies the code
and takes advantage of VM_FAULT_RETRY functionality when faulting in pages.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This removes the 'write' and 'force' from get_user_pages() and replaces
them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers
as use of this flag can result in surprising behaviour (and hence bugs)
within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit d4edcf0d56 ("mm/gup: Switch all callers of get_user_pages() to
not pass tsk/mm") switched get_user_pages() callers to the simpler model
where they no longer pass in the thread and mm pointer. But since then
we've merged changes to a few drivers that re-introduce use of the old
interface. Let's fix them up.
They continued to work fine (thanks to the truly disgusting macros
introduced in commit cde70140fe: "mm/gup: Overload get_user_pages()
functions"), but cause unnecessary build noise.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is the big staging driver pull request for 4.6-rc1.
Lots of little things here, over 1600 patches or so. Notible is all of
the good Lustre work happening, those developers have finally woken up
and are cleaning up their code greatly. The Outreachy intern
application process is also happening, which brought in another 400 or
so patches. Full details are in the very long shortlog.
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver updates from Greg KH:
"Here is the big staging driver pull request for 4.6-rc1.
Lots of little things here, over 1600 patches or so. Notable is all
of the good Lustre work happening, those developers have finally woken
up and are cleaning up their code greatly. The Outreachy intern
application process is also happening, which brought in another 400 or
so patches. Full details are in the very long shortlog.
All of these have been in linux-next with no reported issues"
* tag 'staging-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1673 commits)
staging: lustre: fix aligments in lnet selftest
staging: lustre: report minimum of two buffers for LNet selftest load test
staging: lustre: test for proper errno code in lstcon_rpc_trans_abort
staging: lustre: filter remaining extra spacing for lnet selftest
staging: lustre: remove extra spacing when setting variable for lnet selftest
staging: lustre: remove extra spacing of variable declartions for lnet selftest
staging: lustre: fix spacing issues checkpatch reported in lnet selftest
staging: lustre: remove returns in void function for lnet selftest
staging: lustre: fix bogus lst errors for lnet selftest
staging: netlogic: Replacing pr_err with dev_err after the call to devm_kzalloc
staging: mt29f_spinand: Replacing pr_info with dev_info after the call to devm_kzalloc
staging: android: ion: fix up file mode
staging: ion: debugfs invalid gfp mask
staging: rts5208: Replace pci_enable_device with pcim_enable_device
Staging: ieee80211: Place constant on right side of the test.
staging: speakup: Replace del_timer with del_timer_sync
staging: lowmemorykiller: fix 2 checks that checkpatch complained
staging: mt29f_spinand: Drop void pointer cast
staging: rdma: hfi1: file_ops: Replace ALIGN with PAGE_ALIGN
staging: rdma: hfi1: driver: Replace IS_ALIGNED with PAGE_ALIGNED
...
Add missing HAS_IOMEM dependency to fix the allyesconfig build error on
ARCH=um (for x86_64):
drivers/platform/goldfish/pdev_bus.c: In function ‘goldfish_pdev_bus_probe’:
drivers/platform/goldfish/pdev_bus.c:191:18: error: implicit declaration of function ‘ioremap’ [-Werror=implicit-function-declaration]
pdev_bus_base = ioremap(pdev_bus_addr, pdev_bus_len);
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This resolves the merge issues and confusions people were having with
the goldfish drivers due to changes for them showing up in two different
trees.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Coherent mapping guarantees that the device and CPU are in sync.
Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We recently messed up the error handling here. We can return with the
pipe->lock held or sometimes we unlock twice by mistake.
Fixes: 2f3be88237 ('goldfish_pipe: Pin pages to memory while copying and other cleanups')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add ACPI binding to the android pipe driver
Signed-off-by: Jason Hu <jia-cheng.hu@intel.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For reading and writing guest user space buffers, currently the kernel
sends the guest virtual address of the buffer to the pipe device. This
virtual address has to be first converted to a guest physical address.
Doing this translation on the QEMU side is inefficient and requires
additional handling when KVM is enabled, whose implementation would
either incur intrusive changes to QEMU's KVM support code or suffer
from poor performance, see commit 08c7228c50f8 ("x86-kvm: only sync
SREGS when doing address translation") of $AOSP/external/qemu for
details, and thus should be avoided if possible.
There is a TODO comment in hw/misc/android_pipe.c in the new Android
emulator source tree ($AOSP/external/qemu-android) which requests that
the translation be done on the kernel side and that physical addresses
be passed to the device instead of virtual ones. Once the QEMU-side
implementation is done, the kernel will need to support both the new
paddr-based pipe device and the old vaddr-based one (which will
continue to be used by the classic emulator). This patch achieves that
by leveraging the device version register available in the new device.
See https://android-review.googlesource.com/128280 for the QEMU-side
patch.
In addition, use the mmap semaphore (in read mode) to safeguard the
call to get_user_pages().
Signed-off-by: Yu Ning <yu.ning@intel.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On PIPE_ERROR_AGAIN, just stopping in the middle of a transfer and
returning the number of bytes actually handled is the right behavior.
Other errors should be returned on the next read() or write() call.
Continue logging those until we confirm nothing actually relies on the
existing (wrong) behavior of dropping errors on the floor.
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add bindings so we don't need to rely on goldfish virtual bus for
probing any more, which means we don't need ARM and MIPS goldfish
board code for instantiating the bus.
In the long term we would like to move towards replacing the Android
pipe with virtio-vsock that is currently under development.
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The existing code had a troubling TODO statement concerning the fact
that it just did a check if the page that the QEMU backend was going to
read from / write to was there before the call to the QEMU backend and
then relying on the fact that the page stayed around, even in a
preemptible SMP kernel. Obviously the page could go away or be
reassigned, and strange things may happen.
Further, writes were not tracked, so any use of COW or KSM-like
features would break completely. Probably that was never used by adbd
(the only current active user of the pipe), but could prove much more
dangerous for the GPU passthrough mechanism.
Instead, use get_user_pages() as the comment suggested and cleanup the
error path and add the set_page_dirt() call on a successful read
operation.
Also clarify the count used to return from successful read/write calls
and use Linux style commentary in various places of the file.
Note: The "just ignore error and return whatever we read so far" error
handling is really quite horrific. I cannot change it without a more
careful study of all user space ABIs reliance on this 'feature'.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It just makes it harder to figure out which commands are being used.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On new virtual devices, the goldfish virtual bus can be replaced with
autoprobing infrastructure like Device Tree. Refactor the goldfish
kernel configs to better accommodate this.
Move the goldfish platform into a menuconfig in the style of the chrome
platform, and separate the goldfish bus into its own config option.
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Jin Qian <jinqian@android.com>
[Corrected a tristate to bool]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'module-builtin_driver-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
Pull module_platform_driver replacement from Paul Gortmaker:
"Replace module_platform_driver with builtin_platform driver in non
modules.
We see an increasing number of non-modular drivers using
modular_driver() type register functions. There are several downsides
to letting this continue unchecked:
- The code can appear modular to a reader of the code, and they won't
know if the code really is modular without checking the Makefile
and Kconfig to see if compilation is governed by a bool or
tristate.
- Coders of drivers may be tempted to code up an __exit function that
is never used, just in order to satisfy the required three args of
the modular registration function.
- Non-modular code ends up including the <module.h> which increases
CPP overhead that they don't need.
- It hinders us from performing better separation of the module init
code and the generic init code.
So here we introduce similar macros for builtin drivers. Then we
convert builtin drivers (controlled by a bool Kconfig) by making the
following type of mapping:
module_platform_driver() ---> builtin_platform_driver()
module_platform_driver_probe() ---> builtin_platform_driver_probe().
The set of drivers that are converted here are just the ones that
showed up as relying on an implicit include of <module.h> during a
pending header cleanup. So we convert them here vs adding an include
of <module.h> to non-modular code to avoid compile fails. Additonal
conversions can be done asynchronously at any time.
Once again, an unused module_exit function that is removed here
appears in the diffstat as an outlier wrt all the other changes"
* tag 'module-builtin_driver-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
drivers/clk: convert sunxi/clk-mod0.c to use builtin_platform_driver
drivers/power: Convert non-modular syscon-reboot to use builtin_platform_driver
drivers/soc: Convert non-modular soc-realview to use builtin_platform_driver
drivers/soc: Convert non-modular tegra/pmc to use builtin_platform_driver
drivers/cpufreq: Convert non-modular s5pv210-cpufreq.c to use builtin_platform_driver
drivers/cpuidle: Convert non-modular drivers to use builtin_platform_driver
drivers/platform: Convert non-modular pdev_bus to use builtin_platform_driver
platform_device: better support builtin boilerplate avoidance
Here's the big, really big, staging tree patches for 4.2-rc1.
Loads of stuff in here, almost all just coding style fixes / churn, and
a few new drivers as well, one of which I just disabled from the build a
few minutes ago due to way too many build warnings.
Other than the one "disable this driver" patch, all of these have been
in linux-next for quite a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver updates from Greg KH:
"Here's the big, really big, staging tree patches for 4.2-rc1.
Loads of stuff in here, almost all just coding style fixes / churn,
and a few new drivers as well, one of which I just disabled from the
build a few minutes ago due to way too many build warnings.
Other than the one "disable this driver" patch, all of these have been
in linux-next for quite a while with no reported issues"
* tag 'staging-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1163 commits)
staging: wilc1000: disable driver due to build warnings
Staging: rts5208: fix CHANGE_LINK_STATE value
Staging: sm750fb: ddk750_swi2c.c: Insert spaces before parenthesis
Staging: sm750fb: ddk750_swi2c.c: Place braces on correct lines
Staging: sm750fb: ddk750_swi2c.c: Insert spaces around operators
Staging: sm750fb: ddk750_swi2c.c: Replace spaces with tabs
Staging: sm750fb: ddk750_swi2c.h: Shorten lines to under 80 characters
Staging: sm750fb: ddk750_swi2c.h: Replace spaces with tabs
Staging: sm750fb: modedb.h: Shorten lines to under 80 characters
Staging: sm750fb: modedb.h: Replace spaces with tabs
staging: comedi: addi_apci_3120: rename 'this_board' variables
staging: comedi: addi_apci_1516: rename 'this_board' variables
staging: comedi: ni_atmio: cleanup ni_getboardtype()
staging: comedi: vmk80xx: sanity check context used to get the boardinfo
staging: comedi: vmk80xx: rename 'boardinfo' variables
staging: comedi: dt3000: rename 'this_board' variables
staging: comedi: adv_pci_dio: rename 'this_board' variables
staging: comedi: cb_pcidas64: rename 'thisboard' variables
staging: comedi: cb_pcidas: rename 'thisboard' variables
staging: comedi: me4000: rename 'thisboard' variables
...
This driver is configured with a Kconfig option that is
declared as a bool. Hence it is not possible for the code
to be built as modular. However the code is currently using
the module_platform_driver() macro for driver registration.
While this currently works, we really don't want to be including
the module.h header in non-modular code, which we'll be forced
to do, pending some upcoming code relocation from init.h into
module.h. So we fix it now by using the non-modular equivalent.
And since we've already established that the code is non-modular,
we can completely drop any code relating to module_exit.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
As the first argument of gf_write64() was of type unsigned long, and as
some calls to gf_write64() were casting the first argument from void *
to u64 the compiler and/or sparse were printing warnings for casts of
wrong sizes when compiling for i386.
This patch changes the type of the first argument of gf_write64() to
const void *, and update calls to the function. This change fixed the
warnings and allowed to remove casts from 3 calls to gf_write64().
In addition gf_write64() was renamed to gf_write_ptr() as the name was
misleading because it only writes 32 bits on 32 bit systems.
gf_write_dma_addr() was added to handle dma_addr_t values which is
used at drivers/staging/goldfish/goldfish_audio.c.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/platform/goldfish/goldfish_pipe.c: In function 'goldfish_cmd_status':
drivers/platform/goldfish/goldfish_pipe.c:164:14: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
writel((u32)(u64)pipe, dev->base + PIPE_REG_CHANNEL);
^
drivers/platform/goldfish/goldfish_pipe.c: In function 'goldfish_cmd':
drivers/platform/goldfish/goldfish_pipe.c:180:14: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
writel((u32)(u64)pipe, dev->base + PIPE_REG_CHANNEL);
^
drivers/platform/goldfish/goldfish_pipe.c: In function 'goldfish_pipe_read_write':
drivers/platform/goldfish/goldfish_pipe.c:337:16: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
writel((u32)(u64)pipe, dev->base + PIPE_REG_CHANNEL);
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Jun Tian <jun.j.tian@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/platform/goldfish/pdev_bus.c: In function 'goldfish_new_pdev':
drivers/platform/goldfish/pdev_bus.c:136:14: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
writel((u32)(u64)name, pdev_bus_base + PDEV_BUS_GET_NAME);
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Jun Tian <jun.j.tian@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the 64bit helper method to scrub most of the ifdefs from the driver. The
pipe reading has a funny case we can't scrub completely.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patchs adds a new register to pass the upper 32bits for the
device name address when running in 64bit mode.
Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Jun Tian <jun.j.tian@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using multiple adb on 64 bit kernel to transfer data,
the goldfish pipe interrupt will crash the kernel.
Signed-off-by: Jun Tian <jun.j.tian@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Support 64-bit channel and address for the goldfish pipe driver.
Signed-off-by: Jun Tian <jun.j.tian@intel.com>
Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Brian Wood <brian.j.wood@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a bug fix that has been lurking in the Google tree but not pushed
upstream.
From: Octavian Purdila <octavian.purdila@intel.com>
The memory region is already reserved in goldfish_init() during
platform init.
Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Jun Tian <jun.j.tian@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Note a point in the pipe driver that wants future attention
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A QEMU pipe is a very fast communication channel between the
guest system and the emulator. Usage from the guest is simply
something like;
// connect to special device
fd = open("/dev/qemu_pipe", O_RDWR);
// tell which service we want to talk to (must be zero-terminated)
write(fd, "pipeName", strlen("pipeName")+1);
// do read()/write() through fd now
...
// close channel
close(fd);
Signed-off-by: David 'Digit' Turner <digit@android.com>
[Added support for parameter buffers for speed]
igned-off-by: Xin, Xiaohui <xiaohui.xin@intel.com>
Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com>
Signed-off-by: Nakajima, Jun <jun.nakajima@intel.com>
[Ported to 3.6]
Signed-off-by: Tom Keel <thomas.keel@intel.com>
[Ported to 3.7, moved to platform/goldfish]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This imports the current Google code and cleans it up slightly to use pr_ and
to properly request its resources.
Goldfish is an emulator used for Android development. It has a virtual bus where
the emulator passes platform device information to the guest which then creates
the appropriate devices.
This part of the emulation is not architecture specific so should not be hiding
in architecture trees as it does in the Google Android tree. The constants it
uses do depend on the platform and the platform creates the bus device which then
talks to the emulator to ascertain the actual devices present.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Xiaohui Xin <xiaohui.xin@intel.com>
Signed-off-by: Jun Nakajima <jun.nakajima@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
[Moved out of x86, cleaned up headers]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
