drm/exynos: fix race condition UAF in exynos_g2d_exec_ioctl

If it is async, runqueue_node is freed in g2d_runqueue_worker on another
worker thread. So in extreme cases, if g2d_runqueue_worker runs f

drm/exynos: fix race condition UAF in exynos_g2d_exec_ioctl

If it is async, runqueue_node is freed in g2d_runqueue_worker on another
worker thread. So in extreme cases, if g2d_runqueue_worker runs first, and
then executes the following if statement, there will be use-after-free.

Signed-off-by: Min Li <lm0963hack@gmail.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

show more ...

drm: exynos: Remove #ifdef guards for PM related functions

Use the DEFINE_RUNTIME_DEV_PM_OPS(), SYSTEM_SLEEP_PM_OPS(),
RUNTIME_PM_OPS() and pm_ptr() macros to handle the runtime and suspend
PM callb

drm: exynos: Remove #ifdef guards for PM related functions

Use the DEFINE_RUNTIME_DEV_PM_OPS(), SYSTEM_SLEEP_PM_OPS(),
RUNTIME_PM_OPS() and pm_ptr() macros to handle the runtime and suspend
PM callbacks.

These macros allow the suspend and resume functions to be automatically
dropped by the compiler when CONFIG_PM is disabled, without having
to use #ifdef guards.

This has the advantage of always compiling these functions in,
independently of any Kconfig option. Thanks to that, bugs and other
regressions are subsequently easier to catch.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Inki Dae <inki.dae@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221129191733.137897-10-paul@crapouillou.net

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drm/exynos: remove FOLL_FORCE usage

FOLL_FORCE is really only for ptrace access. As we unpin the pinned pages
using unpin_user_pages_dirty_lock(true), the assumption is that all these
pages are writ

drm/exynos: remove FOLL_FORCE usage

FOLL_FORCE is really only for ptrace access. As we unpin the pinned pages
using unpin_user_pages_dirty_lock(true), the assumption is that all these
pages are writable.

FOLL_FORCE in this case seems to be a legacy leftover. Let's just remove
it.

Link: https://lkml.kernel.org/r/20221116102659.70287-18-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: David Airlie <airlied@gmail.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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drm/exynos: Make use of the helper function devm_platform_ioremap_resource()

Use the devm_platform_ioremap_resource() helper instead of
calling platform_get_resource() and devm_ioremap_resource()
se

drm/exynos: Make use of the helper function devm_platform_ioremap_resource()

Use the devm_platform_ioremap_resource() helper instead of
calling platform_get_resource() and devm_ioremap_resource()
separately

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: Convert from atomic_t to refcount_t on g2d_cmdlist_userptr->refcount

refcount_t type and corresponding API can protect refcounters from
accidental underflow and overflow and further use-

drm/exynos: Convert from atomic_t to refcount_t on g2d_cmdlist_userptr->refcount

refcount_t type and corresponding API can protect refcounters from
accidental underflow and overflow and further use-after-free situations.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: g2d: fix missing unlock on error in g2d_runqueue_worker()

Add the missing unlock before return from function g2d_runqueue_worker()
in the error handling case.

Fixes: 445d3bed75de ("drm/

drm/exynos: g2d: fix missing unlock on error in g2d_runqueue_worker()

Add the missing unlock before return from function g2d_runqueue_worker()
in the error handling case.

Fixes: 445d3bed75de ("drm/exynos: use pm_runtime_resume_and_get()")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: use pm_runtime_resume_and_get()

Use pm_runtime_resume_and_get() instead of pm_runtime_get_sync()
to deal with usage counter. pm_runtime_get_sync() increases the
usage counter even when i

drm/exynos: use pm_runtime_resume_and_get()

Use pm_runtime_resume_and_get() instead of pm_runtime_get_sync()
to deal with usage counter. pm_runtime_get_sync() increases the
usage counter even when it failed, which makes callers to forget
to decrease the usage counter and resulted in reference leak.

pm_runtime_resume_and_get() function decreases the usage counter
when it failed internally so it can avoid the reference leak.

Changelog v1:
- Fix an build error reported by kernel test robot of Intel.

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Reported-by: kernel test robot <lkp@intel.com>

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drm/exynos: Use FOLL_LONGTERM for g2d cmdlists

The exynos g2d interface is very unusual, but it looks like the
userptr objects are persistent. Hence they need FOLL_LONGTERM.

Signed-off-by: Daniel V

drm/exynos: Use FOLL_LONGTERM for g2d cmdlists

The exynos g2d interface is very unusual, but it looks like the
userptr objects are persistent. Hence they need FOLL_LONGTERM.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-3-daniel.vetter@ffwll.ch

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drm/exynos: Stop using frame_vector helpers

All we need are a pages array, pin_user_pages_fast can give us that
directly. Plus this avoids the entire raw pfn side of get_vaddr_frames.

Note that pin

drm/exynos: Stop using frame_vector helpers

All we need are a pages array, pin_user_pages_fast can give us that
directly. Plus this avoids the entire raw pfn side of get_vaddr_frames.

Note that pin_user_pages_fast is a safe replacement despite the
seeming lack of checking for vma->vm_flasg & (VM_IO | VM_PFNMAP). Such
ptes are marked with pte_mkspecial (which pup_fast rejects in the
fastpath), and only architectures supporting that support the
pin_user_pages_fast fastpath.

Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-2-daniel.vetter@ffwll.ch

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drm: exynos: fix common struct sg_table related issues

The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
returns the number of the created entries in the DMA address space.
H

drm: exynos: fix common struct sg_table related issues

The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
returns the number of the created entries in the DMA address space.
However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and
dma_unmap_sg must be called with the original number of the entries
passed to the dma_map_sg().

struct sg_table is a common structure used for describing a non-contiguous
memory buffer, used commonly in the DRM and graphics subsystems. It
consists of a scatterlist with memory pages and DMA addresses (sgl entry),
as well as the number of scatterlist entries: CPU pages (orig_nents entry)
and DMA mapped pages (nents entry).

It turned out that it was a common mistake to misuse nents and orig_nents
entries, calling DMA-mapping functions with a wrong number of entries or
ignoring the number of mapped entries returned by the dma_map_sg()
function.

To avoid such issues, lets use a common dma-mapping wrappers operating
directly on the struct sg_table objects and use scatterlist page
iterators where possible. This, almost always, hides references to the
nents and orig_nents entries, making the code robust, easier to follow
and copy/paste safe.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by : Inki Dae <inki.dae@samsung.com>

show more ...

drm/exynos: Remove dev_err() on platform_get_irq() failure

platform_get_irq() will call dev_err() itself on failure,
so there is no need for the driver to also do this.
This is detected by coccinell

drm/exynos: Remove dev_err() on platform_get_irq() failure

platform_get_irq() will call dev_err() itself on failure,
so there is no need for the driver to also do this.
This is detected by coccinelle.

Signed-off-by: Tamseel Shams <m.shams@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

show more ...

drm/exynos: Fix cleanup of IOMMU related objects

Store the IOMMU mapping created by the device core of each Exynos DRM
sub-device and restore it when the Exynos DRM driver is unbound. This
fixes IOM

drm/exynos: Fix cleanup of IOMMU related objects

Store the IOMMU mapping created by the device core of each Exynos DRM
sub-device and restore it when the Exynos DRM driver is unbound. This
fixes IOMMU initialization failure for the second time when a deferred
probe is triggered from the bind() callback of master's compound DRM
driver. This also fixes the following issue found using kmemleak
detector:

unreferenced object 0xc2137640 (size 64):
comm "swapper/0", pid 1, jiffies 4294937900 (age 3127.400s)
hex dump (first 32 bytes):
50 a3 14 c2 80 a2 14 c2 01 00 00 00 20 00 00 00 P........... ...
00 10 00 00 00 80 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<3acd268d>] arch_setup_dma_ops+0x4c/0x104
[<9f7d2cce>] of_dma_configure+0x19c/0x3a4
[<ba07704b>] really_probe+0xb0/0x47c
[<4f510e4f>] driver_probe_device+0x78/0x1c4
[<7481a0cf>] device_driver_attach+0x58/0x60
[<0ff8f5c1>] __driver_attach+0xb8/0x158
[<86006144>] bus_for_each_dev+0x74/0xb4
[<10159dca>] bus_add_driver+0x1c0/0x200
[<8a265265>] driver_register+0x74/0x108
[<e0f3451a>] exynos_drm_init+0xb0/0x134
[<db3fc7ba>] do_one_initcall+0x90/0x458
[<6da35917>] kernel_init_freeable+0x188/0x200
[<db3f74d4>] kernel_init+0x8/0x110
[<1f3cddf9>] ret_from_fork+0x14/0x20
[<8cd12507>] 0x0
unreferenced object 0xc214a280 (size 128):
comm "swapper/0", pid 1, jiffies 4294937900 (age 3127.400s)
hex dump (first 32 bytes):
00 a0 ec ed 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<3acd268d>] arch_setup_dma_ops+0x4c/0x104
[<9f7d2cce>] of_dma_configure+0x19c/0x3a4
[<ba07704b>] really_probe+0xb0/0x47c
[<4f510e4f>] driver_probe_device+0x78/0x1c4
[<7481a0cf>] device_driver_attach+0x58/0x60
[<0ff8f5c1>] __driver_attach+0xb8/0x158
[<86006144>] bus_for_each_dev+0x74/0xb4
[<10159dca>] bus_add_driver+0x1c0/0x200
[<8a265265>] driver_register+0x74/0x108
[<e0f3451a>] exynos_drm_init+0xb0/0x134
[<db3fc7ba>] do_one_initcall+0x90/0x458
[<6da35917>] kernel_init_freeable+0x188/0x200
[<db3f74d4>] kernel_init+0x8/0x110
[<1f3cddf9>] ret_from_fork+0x14/0x20
[<8cd12507>] 0x0
unreferenced object 0xedeca000 (size 4096):
comm "swapper/0", pid 1, jiffies 4294937900 (age 3127.400s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<3acd268d>] arch_setup_dma_ops+0x4c/0x104
[<9f7d2cce>] of_dma_configure+0x19c/0x3a4
[<ba07704b>] really_probe+0xb0/0x47c
[<4f510e4f>] driver_probe_device+0x78/0x1c4
[<7481a0cf>] device_driver_attach+0x58/0x60
[<0ff8f5c1>] __driver_attach+0xb8/0x158
[<86006144>] bus_for_each_dev+0x74/0xb4
[<10159dca>] bus_add_driver+0x1c0/0x200
[<8a265265>] driver_register+0x74/0x108
[<e0f3451a>] exynos_drm_init+0xb0/0x134
[<db3fc7ba>] do_one_initcall+0x90/0x458
[<6da35917>] kernel_init_freeable+0x188/0x200
[<db3f74d4>] kernel_init+0x8/0x110
[<1f3cddf9>] ret_from_fork+0x14/0x20
[<8cd12507>] 0x0
unreferenced object 0xc214a300 (size 128):
comm "swapper/0", pid 1, jiffies 4294937900 (age 3127.400s)
hex dump (first 32 bytes):
00 a3 14 c2 00 a3 14 c2 00 40 18 c2 00 80 18 c2 .........@......
02 00 02 00 ad 4e ad de ff ff ff ff ff ff ff ff .....N..........
backtrace:
[<08cbd8bc>] iommu_domain_alloc+0x24/0x50
[<b835abee>] arm_iommu_create_mapping+0xe4/0x134
[<3acd268d>] arch_setup_dma_ops+0x4c/0x104
[<9f7d2cce>] of_dma_configure+0x19c/0x3a4
[<ba07704b>] really_probe+0xb0/0x47c
[<4f510e4f>] driver_probe_device+0x78/0x1c4
[<7481a0cf>] device_driver_attach+0x58/0x60
[<0ff8f5c1>] __driver_attach+0xb8/0x158
[<86006144>] bus_for_each_dev+0x74/0xb4
[<10159dca>] bus_add_driver+0x1c0/0x200
[<8a265265>] driver_register+0x74/0x108
[<e0f3451a>] exynos_drm_init+0xb0/0x134
[<db3fc7ba>] do_one_initcall+0x90/0x458
[<6da35917>] kernel_init_freeable+0x188/0x200
[<db3f74d4>] kernel_init+0x8/0x110
[<1f3cddf9>] ret_from_fork+0x14/0x20

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

show more ...

drm/exynos: remove redundant assignment to pointer 'node'

The pointer 'node' is being assigned with a value that is never
read and is re-assigned later. The assignment is redundant and
can be remove

drm/exynos: remove redundant assignment to pointer 'node'

The pointer 'node' is being assigned with a value that is never
read and is re-assigned later. The assignment is redundant and
can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Inki Dae <daeinki@gmail.com>

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drm/exynos: drop drmP.h usage

Drop use of the deprecated drmP.h file.
Replace with forwards / externals as appropriate.

While touching the list of include files divide
them up in blocks and sort th

drm/exynos: drop drmP.h usage

Drop use of the deprecated drmP.h file.
Replace with forwards / externals as appropriate.

While touching the list of include files divide
them up in blocks and sort them.

v3:
- fix build errors in exynos_drm_g2d.c (Inki Dae)
The exynos_drm_g2d.c file is not built in the
standard configurations and was therefore missed.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Fixed merge conflict.
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 423

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 423

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundationr

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 7 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190113.913773588@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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drm/exynos: use DRM_DEV_ERROR to print out error message

This patch just cleans up the use of error log macro, which changes
the log macro to DRM_DEV_ERROR.

Signed-off-by: Inki Dae <inki.dae@samsun

drm/exynos: use DRM_DEV_ERROR to print out error message

This patch just cleans up the use of error log macro, which changes
the log macro to DRM_DEV_ERROR.

Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: g2d: remove style error

Remove checkpatch error, "foo* bar" should be "foo *bar".

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drm/exynos/iommu: integrate IOMMU/DMA internal API

Exynos DRM drivers should work with and without IOMMU. Providing common
API generic to both scenarios should make code cleaner and allow further
co

drm/exynos/iommu: integrate IOMMU/DMA internal API

Exynos DRM drivers should work with and without IOMMU. Providing common
API generic to both scenarios should make code cleaner and allow further
code improvements.
The patch removes including of exynos_drm_iommu.h as the file contains
mostly IOMMU specific stuff, instead it exposes exynos_drm_*_dma functions
and puts them into exynos_drm_dma.c.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: simplify DMA mapping

Moving DMA mapping creation to drm_iommu_attach_device allows to avoid
looping through all components and maintaining DMA device flags.

v2: take care of configurati

drm/exynos: simplify DMA mapping

Moving DMA mapping creation to drm_iommu_attach_device allows to avoid
looping through all components and maintaining DMA device flags.

v2: take care of configurations without IOMMU

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: gem: Simplify access to exynos GEM objects

Replace all calls to exynos_drm_gem_get_{dma_addr,size}, by a simpler
function exynos_drm_gem_get(). This lets the caller to get access to
exyn

drm/exynos: gem: Simplify access to exynos GEM objects

Replace all calls to exynos_drm_gem_get_{dma_addr,size}, by a simpler
function exynos_drm_gem_get(). This lets the caller to get access to
exynos_drm_gem object and extract any information about GEM object
without searching object tree for getting each parameter.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: g2d: Convert to driver component API

Exynos G2D driver is the last client of the custom Exynos 'sub-driver'
framework. In the current state it doesn't really resolve any of the
issues it

drm/exynos: g2d: Convert to driver component API

Exynos G2D driver is the last client of the custom Exynos 'sub-driver'
framework. In the current state it doesn't really resolve any of the
issues it has been designed for, as Exynos DRM is already built only
as a single kernel module. Remove the custom 'sub-driver' framework and
simply use generic component framework also in G2D driver.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: g2d: Delete an error message for a failed memory allocation in two functions

Omit an extra message for a memory allocation failure in these functions.

This issue was detected by using t

drm/exynos: g2d: Delete an error message for a failed memory allocation in two functions

Omit an extra message for a memory allocation failure in these functions.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: g2d: use monotonic timestamps

The exynos DRM driver uses real-time 'struct timeval' values
for exporting its timestamps to user space. This has multiple
problems:

1. signed seconds over

drm/exynos: g2d: use monotonic timestamps

The exynos DRM driver uses real-time 'struct timeval' values
for exporting its timestamps to user space. This has multiple
problems:

1. signed seconds overflow in y2038
2. the 'struct timeval' definition is deprecated in the kernel
3. time may jump or go backwards after a 'settimeofday()' syscall
4. other DRM timestamps are in CLOCK_MONOTONIC domain, so they
can't be compared
5. exporting microseconds requires a division by 1000, which may
be slow on some architectures.

The code existed in two places before, but the IPP portion was
removed in 8ded59413ccc ("drm/exynos: ipp: Remove Exynos DRM
IPP subsystem"), so we no longer need to worry about it.

Ideally timestamps should just use 64-bit nanoseconds instead, but
of course we can't change that now. Instead, this tries to address
the first four points above by using monotonic 'timespec' values.

According to Tobias Jakobi, user space doesn't care about the
timestamp at the moment, so we can change the format. Even if
there is something looking at them, it will work just fine with
monotonic times as long as the application only looks at the
relative values between two events.

Link: https://patchwork.kernel.org/patch/10038593/
Cc: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: g2d: change platform driver name to 'exynos-drm-g2d'

The current name is 's5p-g2d', which is identical with the driver
name of the old V4L2 driver in media/platform.
This is probably due

drm/exynos: g2d: change platform driver name to 'exynos-drm-g2d'

The current name is 's5p-g2d', which is identical with the driver
name of the old V4L2 driver in media/platform.
This is probably due to the DRM driver being based on the V4L2
driver when it was initially created. Still the clashing of driver
names is confusing, so rename it to something in line with the
other DRM subdrivers.

Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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drm/exynos: g2d: prevent integer overflow in

The size computations done in the ioctl function use an integer.
If userspace submits a request with req->cmd_nr or req->cmd_buf_nr
set to INT_MAX, the i

drm/exynos: g2d: prevent integer overflow in

The size computations done in the ioctl function use an integer.
If userspace submits a request with req->cmd_nr or req->cmd_buf_nr
set to INT_MAX, the integer computations overflow later, leading
to potential (kernel) memory corruption.

Prevent this issue by enforcing a limit on the number of submitted
commands, so that we have enough headroom later for the size
computations.

Note that this change has no impact on the currently available
users in userspace, like e.g. libdrm/exynos.

While at it, also make a comment about the size computation more
detailed.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

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