Make use of the same atomic pool as DMA does, and skip a kernel page
mapping which can involve sleep'able operations at allocating a kernel
page table.
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Support atomic allocation in __iommu_get_pages().
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
[moved __atomic_get_pages() under #ifdef CONFIG_ARM_DMA_USE_IOMMU
to avoid unused fuction warning for no-IOMMU case]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Check the given range("start", "size") is included in "atomic_pool" or not.
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
struct page **pages is necessary to align with non atomic path in
__iommu_get_pages(). atomic_pool() has the intialized **pages instead
of just *page.
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Print a loud warning when system runs out of memory from atomic DMA
coherent pool to let users notice the potential problem.
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Some platforms might require to increase atomic coherent pool to make
sure that their device will be able to allocate all their buffers from
atomic context. This function can be also used to decrease atomic
coherent pool size if coherent allocations are not used for the given
sub-platform.
Suggested-by: Josh Coombs <josh.coombs@gmail.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Pull ARM fixes from Russell King:
"The largest thing in this set of changes is bringing back some of the
ARMv3 code to fix a compile problem noticed on RiscPC, which we still
support, even though we only support ARMv4 there.
(The reason is that the system bus doesn't support ARMv4 half-word
accesses, so we need the ARMv3 library code for this platform.)
The rest are all quite minor fixes."
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7490/1: Drop duplicate select for GENERIC_IRQ_PROBE
ARM: Bring back ARMv3 IO and user access code
ARM: 7489/1: errata: fix workaround for erratum #720789 on UP systems
ARM: 7488/1: mm: use 5 bits for swapfile type encoding
ARM: 7487/1: mm: avoid setting nG bit for user mappings that aren't present
ARM: 7486/1: sched_clock: update epoch_cyc on resume
ARM: 7484/1: Don't enable GENERIC_LOCKBREAK with ticket spinlocks
ARM: 7483/1: vfp: only advertise VFPv4 in hwcaps if CONFIG_VFPv3 is enabled
ARM: 7482/1: topology: fix section mismatch warning for init_cpu_topology
Commit 5a783cbc48 ("ARM: 7478/1: errata: extend workaround for erratum
#720789") added workarounds for erratum #720789 to the range TLB
invalidation functions with the observation that the erratum only
affects SMP platforms. However, when running an SMP_ON_UP kernel on a
uniprocessor platform we must take care to preserve the ASID as the
workaround is not required.
This patch ensures that we don't set the ASID to 0 when flushing the TLB
on such a system, preserving the original behaviour with the workaround
disabled.
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Swap entries are encoding in ptes such that !pte_present(pte) and
pte_file(pte). The remaining bits of the descriptor are used to identify
the swapfile and offset within it to the swap entry.
When writing such a pte for a user virtual address, set_pte_at
unconditionally sets the nG bit, which (in the case of LPAE) will
corrupt the swapfile offset and lead to a BUG:
[ 140.494067] swap_free: Unused swap offset entry 000763b4
[ 140.509989] BUG: Bad page map in process rs:main Q:Reg pte:0ec76800 pmd:8f92e003
This patch fixes the problem by only setting the nG bit for user
mappings that are actually present.
Cc: <stable@vger.kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The alignment mask is calculated incorrectly. Fixing the calculation
makes strange hangs/lockups disappear during the boot with Amstrad E3
and 3.6-rc1 kernel.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Fix dma_contiguous_remap() so that it continues through all the
regions, even after encountering one that is outside lowmem.
Without this change, if you have two CMA regions, the first outside
lowmem and the seocnd inside lowmem, only the second one will get
set up in the MMU. Data written to that region then doesn't get
automatically flushed from the cache into memory.
Signed-off-by: Chris Brand <cbrand@broadcom.com>
[extended patch subject with 'fix' word]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Pull ARM fixes from Russell King:
"This fixes various issues found during July"
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7479/1: mm: avoid NULL dereference when flushing gate_vma with VIVT caches
ARM: Fix undefined instruction exception handling
ARM: 7480/1: only call smp_send_stop() on SMP
ARM: 7478/1: errata: extend workaround for erratum #720789
ARM: 7477/1: vfp: Always save VFP state in vfp_pm_suspend on UP
ARM: 7476/1: vfp: only clear vfp state for current cpu in vfp_pm_suspend
ARM: 7468/1: ftrace: Trace function entry before updating index
ARM: 7467/1: mutex: use generic xchg-based implementation for ARMv6+
ARM: 7466/1: disable interrupt before spinning endlessly
ARM: 7465/1: Handle >4GB memory sizes in device tree and mem=size@start option
Commit cdf357f1 ("ARM: 6299/1: errata: TLBIASIDIS and TLBIMVAIS
operations can broadcast a faulty ASID") replaced by-ASID TLB flushing
operations with all-ASID variants to workaround A9 erratum #720789.
This patch extends the workaround to include the tlb_range operations,
which were overlooked by the original patch.
Cc: <stable@vger.kernel.org>
Tested-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull DMA-mapping updates from Marek Szyprowski:
"Those patches are continuation of my earlier work.
They contains extensions to DMA-mapping framework to remove limitation
of the current ARM implementation (like limited total size of DMA
coherent/write combine buffers), improve performance of buffer sharing
between devices (attributes to skip cpu cache operations or creation
of additional kernel mapping for some specific use cases) as well as
some unification of the common code for dma_mmap_attrs() and
dma_mmap_coherent() functions. All extensions have been implemented
and tested for ARM architecture."
* 'for-linus-for-3.6-rc1' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
ARM: dma-mapping: add support for DMA_ATTR_SKIP_CPU_SYNC attribute
common: DMA-mapping: add DMA_ATTR_SKIP_CPU_SYNC attribute
ARM: dma-mapping: add support for dma_get_sgtable()
common: dma-mapping: introduce dma_get_sgtable() function
ARM: dma-mapping: add support for DMA_ATTR_NO_KERNEL_MAPPING attribute
common: DMA-mapping: add DMA_ATTR_NO_KERNEL_MAPPING attribute
common: dma-mapping: add support for generic dma_mmap_* calls
ARM: dma-mapping: fix error path for memory allocation failure
ARM: dma-mapping: add more sanity checks in arm_dma_mmap()
ARM: dma-mapping: remove custom consistent dma region
mm: vmalloc: use const void * for caller argument
scatterlist: add sg_alloc_table_from_pages function
This patch adds support for DMA_ATTR_SKIP_CPU_SYNC attribute for
dma_(un)map_(single,page,sg) functions family. It lets dma mapping clients
to create a mapping for the buffer for the given device without performing
a CPU cache synchronization. CPU cache synchronization can be skipped for
the buffers which it is known that they are already in 'device' domain (CPU
caches have been already synchronized or there are only coherent mappings
for the buffer). For advanced users only, please use it with care.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
This patch adds support for dma_get_sgtable() function which is required
to let drivers to share the buffers allocated by DMA-mapping subsystem.
Generic implementation based on virt_to_page() is not suitable for ARM
dma-mapping subsystem.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
This patch adds support for DMA_ATTR_NO_KERNEL_MAPPING attribute for
IOMMU allocations, what let drivers to save precious kernel virtual
address space for large buffers that are intended to be accessed only
from userspace.
This patch is heavily based on initial work kindly provided by Abhinav
Kochhar <abhinav.k@samsung.com>.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
This patch fixes incorrect check in error path. When the allocation of
first page fails, the kernel ops appears due to accessing -1 element of
the pages array.
Reported-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Add some sanity checks and forbid mmaping of buffers into vma areas larger
than allocated dma buffer.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
This patch changes dma-mapping subsystem to use generic vmalloc areas
for all consistent dma allocations. This increases the total size limit
of the consistent allocations and removes platform hacks and a lot of
duplicated code.
Atomic allocations are served from special pool preallocated on boot,
because vmalloc areas cannot be reliably created in atomic context.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Pull CMA and DMA-mapping fixes from Marek Szyprowski:
"Another set of minor fixups for recently merged Contiguous Memory
Allocator and ARM DMA-mapping changes. Those patches fix mysterious
crashes on systems with CMA and Himem enabled as well as some corner
cases caused by typical off-by-one bug."
* 'fixes-for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
ARM: dma-mapping: modify condition check while freeing pages
mm: cma: fix condition check when setting global cma area
mm: cma: don't replace lowmem pages with highmem
WARNING: at mm/vmalloc.c:1471 __iommu_free_buffer+0xcc/0xd0()
Trying to vfree() nonexistent vm area (ef095000)
Modules linked in:
[<c0015a18>] (unwind_backtrace+0x0/0xfc) from [<c0025a94>] (warn_slowpath_common+0x54/0x64)
[<c0025a94>] (warn_slowpath_common+0x54/0x64) from [<c0025b38>] (warn_slowpath_fmt+0x30/0x40)
[<c0025b38>] (warn_slowpath_fmt+0x30/0x40) from [<c0016de0>] (__iommu_free_buffer+0xcc/0xd0)
[<c0016de0>] (__iommu_free_buffer+0xcc/0xd0) from [<c0229a5c>] (exynos_drm_free_buf+0xe4/0x138)
[<c0229a5c>] (exynos_drm_free_buf+0xe4/0x138) from [<c022b358>] (exynos_drm_gem_destroy+0x80/0xfc)
[<c022b358>] (exynos_drm_gem_destroy+0x80/0xfc) from [<c0211230>] (drm_gem_object_free+0x28/0x34)
[<c0211230>] (drm_gem_object_free+0x28/0x34) from [<c0211bd0>] (drm_gem_object_release_handle+0xcc/0xd8)
[<c0211bd0>] (drm_gem_object_release_handle+0xcc/0xd8) from [<c01abe10>] (idr_for_each+0x74/0xb8)
[<c01abe10>] (idr_for_each+0x74/0xb8) from [<c02114e4>] (drm_gem_release+0x1c/0x30)
[<c02114e4>] (drm_gem_release+0x1c/0x30) from [<c0210ae8>] (drm_release+0x608/0x694)
[<c0210ae8>] (drm_release+0x608/0x694) from [<c00b75a0>] (fput+0xb8/0x228)
[<c00b75a0>] (fput+0xb8/0x228) from [<c00b40c4>] (filp_close+0x64/0x84)
[<c00b40c4>] (filp_close+0x64/0x84) from [<c0029d54>] (put_files_struct+0xe8/0x104)
[<c0029d54>] (put_files_struct+0xe8/0x104) from [<c002b930>] (do_exit+0x608/0x774)
[<c002b930>] (do_exit+0x608/0x774) from [<c002bae4>] (do_group_exit+0x48/0xb4)
[<c002bae4>] (do_group_exit+0x48/0xb4) from [<c002bb60>] (sys_exit_group+0x10/0x18)
[<c002bb60>] (sys_exit_group+0x10/0x18) from [<c000ee80>] (ret_fast_syscall+0x0/0x30)
This patch modifies the condition while freeing to match the condition
used while allocation. This fixes the above warning which arises when
array size is equal to PAGE_SIZE where allocation is done using kzalloc
but free is done using vfree.
Signed-off-by: Prathyush K <prathyush.k@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
This patch introduces a new Kconfig option which, when enabled, causes
the kernel to write the PID of the current task into the PROCID field
of the CONTEXTIDR on context switch. This is useful when analysing
hardware trace, since writes to this register can be configured to emit
an event into the trace stream.
The thread notifier for writing the PID is deliberately kept separate
from the ASID-writing code so that we can support newer processors using
LPAE, where the ASID is stored in TTBR0. As such, the switch_mm code is
updated to perform a read-modify-write sequence to ensure that we don't
clobber the PID on CPUs using the classic 2-level page tables.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>