Atomic pool should always be allocated from DMA zone if such zone is
available in the system to avoid issues caused by limited dma mask of
any of the devices used for making an atomic allocation.
Reported-by: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Stable <stable@vger.kernel.org> [v3.6+]
The ARM ARM requires branch predictor maintenance if, for a given ASID,
the instructions at a specific virtual address appear to change.
From the kernel's point of view, that means:
- Changing the kernel's view of memory (e.g. switching to the
identity map)
- ASID rollover (since ASIDs will be re-allocated to new tasks)
This patch adds explicit branch predictor maintenance when either of the
two conditions above are met.
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>
mm->context.id is updated under asid_lock when a new ASID is allocated
to an mm_struct. However, it is also read without the lock when a task
is being scheduled and checking whether or not the current ASID
generation is up-to-date.
If two threads of the same process are being scheduled in parallel and
the bottom bits of the generation in their mm->context.id match the
current generation (that is, the mm_struct has not been used for ~2^24
rollovers) then the non-atomic, lockless access to mm->context.id may
yield the incorrect ASID.
This patch fixes this issue by making mm->context.id and atomic64_t,
ensuring that the generation is always read consistently. For code that
only requires access to the ASID bits (e.g. TLB flushing by mm), then
the value is accessed directly, which GCC converts to an ldrb.
Cc: <stable@vger.kernel.org> # 3.8
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>
If a thread triggers an ASID rollover, other threads of the same process
must be made to wait until the mm->context.id for the shared mm_struct
has been updated to new generation and associated book-keeping (e.g.
TLB invalidation) has ben performed.
However, there is a *tiny* window where both mm->context.id and the
relevant active_asids entry are updated to the new generation, but the
TLB flush has not been performed, which could allow another thread to
return to userspace with a dirty TLB, potentially leading to data
corruption. In reality this will never occur because one CPU would need
to perform a context-switch in the time it takes another to do a couple
of atomic test/set operations but we should plug the race anyway.
This patch moves the active_asids update until after the potential TLB
flush on context-switch.
Cc: <stable@vger.kernel.org> # 3.8
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>
Fix missing use of the asid macro when getting the ASID from the mm->context.id field.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Paolo Pisati reports that IPv6 triggers this warning:
BUG: scheduling while atomic: swapper/0/0/0x40000100
Modules linked in:
[<c001b1c4>] (unwind_backtrace+0x0/0xf0) from [<c0503c5c>] (__schedule_bug+0x48/0x5c)
[<c0503c5c>] (__schedule_bug+0x48/0x5c) from [<c0508608>] (__schedule+0x700/0x740)
[<c0508608>] (__schedule+0x700/0x740) from [<c007007c>] (__cond_resched+0x24/0x34)
[<c007007c>] (__cond_resched+0x24/0x34) from [<c05086dc>] (_cond_resched+0x3c/0x44)
[<c05086dc>] (_cond_resched+0x3c/0x44) from [<c0021f6c>] (do_alignment+0x178/0x78c)
[<c0021f6c>] (do_alignment+0x178/0x78c) from [<c00083e0>] (do_DataAbort+0x34/0x98)
[<c00083e0>] (do_DataAbort+0x34/0x98) from [<c0509a60>] (__dabt_svc+0x40/0x60)
Exception stack(0xc0763d70 to 0xc0763db8)
3d60: e97e805e e97e806e 2c000000 11000000
3d80: ea86bb00 0000002c 00000011 e97e807e c076d2a8 e97e805e e97e806e 0000002c
3da0: 3d000000 c0763dbc c04b98fc c02a8490 00000113 ffffffff
[<c0509a60>] (__dabt_svc+0x40/0x60) from [<c02a8490>] (__csum_ipv6_magic+0x8/0xc8)
Fix this by using probe_kernel_address() stead of __get_user().
Cc: <stable@vger.kernel.org>
Reported-by: Paolo Pisati <p.pisati@gmail.com>
Tested-by: Paolo Pisati <p.pisati@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch removes page_address() usage in IOMMU-aware dma-mapping
implementation and replaced it with direct use of the cpu virtual address
provided by the caller. page_address() returned incorrect address for
pages remapped in atomic pool, what caused memory leak.
Reported-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Hiroshi Doyu <hdoyu@nvidia.com>
Alignment order for a dma iommu buffer is set by buffer size. For
large buffer, it is a waste of iommu address space. So configurable
parameter to limit maximum alignment order can reduce the waste.
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Kyungmin.park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
IOMMU can provide access to any memory page, so there is no point in
limiting the allocated pages only to lowmem, once other parts of
dma-mapping subsystem correctly supports himem pages.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
This patch adds missing pieces to correctly support memory pages served
from CMA regions placed in high memory zones. Please note that the default
global CMA area is still put into lowmem and is limited by optional
architecture specific DMA zone. One can however put device specific CMA
regions in high memory zone to reduce lowmem usage.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
This patch adds EXPORT_SYMBOL_GPL calls to the three arm iommu
functions - arm_iommu_create_mapping, arm_iommu_free_mapping
and arm_iommu_attach_device. These three functions are arm specific
wrapper functions for creating/freeing/using an iommu mapping and
they are called by various drivers. If any of these drivers need
to be built as dynamic modules, these functions need to be exported.
Changelog v2: using EXPORT_SYMBOL_GPL as suggested by Marek.
Signed-off-by: Prathyush K <prathyush.k@samsung.com>
[m.szyprowski: extended with recently introduced
EXPORT_SYMBOL_GPL(arm_iommu_detach_device)]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
struct dma_map_ops iommu_ops doesn't have ->set_dma_mask, which causes
crash when dma_set_mask() is called from some driver.
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
The mmid macro is meant to be used to get the mm->context.id data
from the mm structure, but it seems to have been missed in a cuple
of files.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since the new ASID code in b5466f8728
("ARM: mm: remove IPI broadcasting on ASID rollover") was changed to
use 64bit operations it has broken the BE operation due to an issue
with the MM code accessing sub-fields of mm->context.id.
When running in BE mode we see the values in mm->context.id are stored
with the highest value first, so the LDR in the arch/arm/mm/proc-macros.S
reads the wrong part of this field. To resolve this, change the LDR in
the mmid macro to load from +4.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
869486d5f51 (ARM: 7646/1: mm: use static_vm for managing static mapped
areas) introduced new warnings:
arch/arm/mm/mmu.c: In function 'pci_reserve_io':
arch/arm/mm/mmu.c:888:16: warning: unused variable 'addr'
arch/arm/mm/mmu.c:887:20: warning: unused variable 'vm'
because it failed to delete the two local variables it no longer used.
Fix this.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
A static mapped area is ARM-specific, so it is better not to use
generic vmalloc data structure, that is, vmlist and vmlist_lock
for managing static mapped area. And it causes some needless overhead and
reducing this overhead is better idea.
Now, we have newly introduced static_vm infrastructure.
With it, we don't need to iterate all mapped areas. Instead, we just
iterate static mapped areas. It helps to reduce an overhead of finding
matched area. And architecture dependency on vmalloc layer is removed,
so it will help to maintainability for vmalloc layer.
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In current implementation, we used ARM-specific flag, that is,
VM_ARM_STATIC_MAPPING, for distinguishing ARM specific static mapped area.
The purpose of static mapped area is to re-use static mapped area when
entire physical address range of the ioremap request can be covered
by this area.
This implementation causes needless overhead for some cases.
For example, assume that there is only one static mapped area and
vmlist has 300 areas. Every time we call ioremap, we check 300 areas for
deciding whether it is matched or not. Moreover, even if there is
no static mapped area and vmlist has 300 areas, every time we call
ioremap, we check 300 areas in now.
If we construct a extra list for static mapped area, we can eliminate
above mentioned overhead.
With a extra list, if there is one static mapped area,
we just check only one area and proceed next operation quickly.
In fact, it is not a critical problem, because ioremap is not frequently
used. But reducing overhead is better idea.
Another reason for doing this work is for removing architecture dependency
on vmalloc layer. I think that vmlist and vmlist_lock is internal data
structure for vmalloc layer. Some codes for debugging and stat inevitably
use vmlist and vmlist_lock. But it is preferable that they are used
as least as possible in outside of vmalloc.c
Now, I introduce an ARM-specific infrastructure for static mapped area. In
the following patch, we will use this and resolve above mentioned problem.
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now, there is no user for vmregion.
So remove it.
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
mach-socfpga is another platform that needs to use
v7_invalidate_l1 to bringup additional cores. There was a comment that
the ideal place for v7_invalidate_l1 should be in arm/mm/cache-v7.S
Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Pavel Machek <pavel@denx.de>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Pavel Machek <pavel@denx.de>
Tested-by: Stephen Warren <swarren@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Olof Johansson <olof@lixom.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Magnus Damm <magnus.damm@gmail.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Realview fails to boot with this warning:
BUG: spinlock lockup suspected on CPU#0, init/1
lock: 0xcf8bde10, .magic: dead4ead, .owner: init/1, .owner_cpu: 0
Backtrace:
[<c00185d8>] (dump_backtrace+0x0/0x10c) from [<c03294e8>] (dump_stack+0x18/0x1c) r6:cf8bde10 r5:cf83d1c0 r4:cf8bde10 r3:cf83d1c0
[<c03294d0>] (dump_stack+0x0/0x1c) from [<c018926c>] (spin_dump+0x84/0x98)
[<c01891e8>] (spin_dump+0x0/0x98) from [<c0189460>] (do_raw_spin_lock+0x100/0x198)
[<c0189360>] (do_raw_spin_lock+0x0/0x198) from [<c032cbac>] (_raw_spin_lock+0x3c/0x44)
[<c032cb70>] (_raw_spin_lock+0x0/0x44) from [<c01c9224>] (pl011_console_write+0xe8/0x11c)
[<c01c913c>] (pl011_console_write+0x0/0x11c) from [<c002aea8>] (call_console_drivers.clone.7+0xdc/0x104)
[<c002adcc>] (call_console_drivers.clone.7+0x0/0x104) from [<c002b320>] (console_unlock+0x2e8/0x454)
[<c002b038>] (console_unlock+0x0/0x454) from [<c002b8b4>] (vprintk_emit+0x2d8/0x594)
[<c002b5dc>] (vprintk_emit+0x0/0x594) from [<c0329718>] (printk+0x3c/0x44)
[<c03296dc>] (printk+0x0/0x44) from [<c002929c>] (warn_slowpath_common+0x28/0x6c)
[<c0029274>] (warn_slowpath_common+0x0/0x6c) from [<c0029304>] (warn_slowpath_null+0x24/0x2c)
[<c00292e0>] (warn_slowpath_null+0x0/0x2c) from [<c0070ab0>] (lockdep_trace_alloc+0xd8/0xf0)
[<c00709d8>] (lockdep_trace_alloc+0x0/0xf0) from [<c00c0850>] (kmem_cache_alloc+0x24/0x11c)
[<c00c082c>] (kmem_cache_alloc+0x0/0x11c) from [<c00bb044>] (__get_vm_area_node.clone.24+0x7c/0x16c)
[<c00bafc8>] (__get_vm_area_node.clone.24+0x0/0x16c) from [<c00bb7b8>] (get_vm_area_caller+0x48/0x54)
[<c00bb770>] (get_vm_area_caller+0x0/0x54) from [<c0020064>] (__alloc_remap_buffer.clone.15+0x38/0xb8)
[<c002002c>] (__alloc_remap_buffer.clone.15+0x0/0xb8) from [<c0020244>] (__dma_alloc+0x160/0x2c8)
[<c00200e4>] (__dma_alloc+0x0/0x2c8) from [<c00204d8>] (arm_dma_alloc+0x88/0xa0)[<c0020450>] (arm_dma_alloc+0x0/0xa0) from [<c00beb00>] (dma_pool_alloc+0xcc/0x1a8)
[<c00bea34>] (dma_pool_alloc+0x0/0x1a8) from [<c01a9d14>] (pl08x_fill_llis_for_desc+0x28/0x568)
[<c01a9cec>] (pl08x_fill_llis_for_desc+0x0/0x568) from [<c01aab8c>] (pl08x_prep_slave_sg+0x258/0x3b0)
[<c01aa934>] (pl08x_prep_slave_sg+0x0/0x3b0) from [<c01c9f74>] (pl011_dma_tx_refill+0x140/0x288)
[<c01c9e34>] (pl011_dma_tx_refill+0x0/0x288) from [<c01ca748>] (pl011_start_tx+0xe4/0x120)
[<c01ca664>] (pl011_start_tx+0x0/0x120) from [<c01c54a4>] (__uart_start+0x48/0x4c)
[<c01c545c>] (__uart_start+0x0/0x4c) from [<c01c632c>] (uart_start+0x2c/0x3c)
[<c01c6300>] (uart_start+0x0/0x3c) from [<c01c795c>] (uart_write+0xcc/0xf4)
[<c01c7890>] (uart_write+0x0/0xf4) from [<c01b0384>] (n_tty_write+0x1c0/0x3e4)
[<c01b01c4>] (n_tty_write+0x0/0x3e4) from [<c01acfe8>] (tty_write+0x144/0x240)
[<c01acea4>] (tty_write+0x0/0x240) from [<c01ad17c>] (redirected_tty_write+0x98/0xac)
[<c01ad0e4>] (redirected_tty_write+0x0/0xac) from [<c00c371c>] (vfs_write+0xbc/0x150)
[<c00c3660>] (vfs_write+0x0/0x150) from [<c00c39c0>] (sys_write+0x4c/0x78)
[<c00c3974>] (sys_write+0x0/0x78) from [<c0014460>] (ret_fast_syscall+0x0/0x3c)
This happens because the DMA allocation code is not respecting atomic
allocations correctly.
GFP flags should not be tested for GFP_ATOMIC to determine if an
atomic allocation is being requested. GFP_ATOMIC is not a flag but
a value. The GFP bitmask flags are all prefixed with __GFP_.
The rest of the kernel tests for __GFP_WAIT not being set to indicate
an atomic allocation. We need to do the same.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add a method (hyp_idmap_setup) to populate a hyp pgd with an
identity mapping of the code contained in the .hyp.idmap.text
section.
Offer a method to drop this identity mapping through
hyp_idmap_teardown.
Make all the above depend on CONFIG_ARM_VIRT_EXT and CONFIG_ARM_LPAE.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
KVM uses the stage-2 page tables and the Hyp page table format,
so we define the fields and page protection flags needed by KVM.
The nomenclature is this:
- page_hyp: PL2 code/data mappings
- page_hyp_device: PL2 device mappings (vgic access)
- page_s2: Stage-2 code/data page mappings
- page_s2_device: Stage-2 device mappings (vgic access)
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Christoffer Dall <c.dall@virtualopensystems.com>
Commit 8fb54284ba {ARM: mm: Add strongly ordered descriptor support}
added XN flag at section level but missed it at PTE level.
Fix it by adding the L_PTE_XN to MT_MEMORY_SO PTE descriptor.
Reported-by: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Subhash Jadavani reported this partial backtrace:
Now consider this call stack from MMC block driver (this is on the ARMv7
based board):
[<c001b50c>] (v7_dma_inv_range+0x30/0x48) from [<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c)
[<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c) from [<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c)
[<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c) from [<c0017ff8>] (dma_map_sg+0x3c/0x114)
This is caused by incrementing the struct page pointer, and running off
the end of the sparsemem page array. Fix this by incrementing by pfn
instead, and convert the pfn to a struct page.
Cc: <stable@vger.kernel.org>
Suggested-by: James Bottomley <JBottomley@Parallels.com>
Tested-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM_VIRT_EXT is a property of CPU_V7, but does not adversely affect
other CPUs that can be built into the same kernel image (i.e. ARMv6+).
This patch defaults ARM_VIRT_EXT to y if CPU_V7, allowing hypervisors
such as KVM to make better use of the option and being able to rely
on hyp-mode boot support.
Signed-off-by: Will Deacon <will.deacon@arm.com>
The use of writel instead of writel_relaxed lead to deadlock in some
situation (SMP on Armada 370 for instance). The use of writel_relaxed
as it was done in the rest of this driver fixes this bug.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes a bug for Aurora L2 cache controller when the
write-through mode is enable. For the clean operation even if we don't
have to flush the lines we still need to invalidate them.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If CONFIG_ARCH_MULTIPLATFORM & CONFIG_ARCH_MVEBU are both enabled,
__v7_pj4b_setup is added between __v7_ca9mp_setup and __v7_setup.
But there's no jump instruction added. If the chip is Cortex A5/A9,
it goes through __v7_pj4b_setup also. It results in system hang.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In order to support secure and non-secure platforms in multi-platform
kernels, errata work-arounds that access secure only registers need to
be disabled. Make all the errata options that fit in this category
depend on !CONFIG_ARCH_MULTIPLATFORM.
This will effectively remove the errata options as platforms are
converted over to multi-platform.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
PL310 errata work-arounds using .set_debug function are only needed on
r3p0 and earlier, so check the rev and only set .set_debug on older revs.
Avoiding debug register accesses fixes aborts on non-secure platforms
like highbank. It is assumed that non-secure platforms needing these
work-arounds have already implemented .set_debug with secure monitor
calls.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
flush_cache_louis flushes the D-side caches to the point of unification
inner-shareable. On uniprocessor CPUs, this is defined as zero and
therefore no flushing will take place. Rather than invent a new interface
for UP systems, instead use our SMP_ON_UP patching code to read the
LoUU from the CLIDR instead.
Cc: <stable@vger.kernel.org>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Update the arm arch_get_unmapped_area[_topdown] functions to make use of
vm_unmapped_area() instead of implementing a brute force search.
[akpm@linux-foundation.org: remove now-unused COLOUR_ALIGN_DOWN()]
Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds support for DMA_ATTR_FORCE_CONTIGUOUS attribute for
dma_alloc_attrs() in IOMMU-aware implementation. For allocating physically
contiguous buffers Contiguous Memory Allocator is used.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
The kvm_seq value has nothing to do what so ever with this other KVM.
Given that KVM support on ARM is imminent, it's best to rename kvm_seq
into something else to clearly identify what it is about i.e. a sequence
number for vmalloc section mappings.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Expose another DMA operations function: arm_dma_set_mask. This
function will be added to a custom DMA ops for Armada 370/XP.
Depending of its configuration Armada 370/XP can be set as a "nearly"
coherent architecture. In this case the DMA ops is made of:
- specific functions for this architecture
- already exposed arm DMA related functions
- the arm_dma_set_mask which was not exposed yet.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
PJ4B is an implementation of the ARMv7 (such as the Cortex A9 for
example) released by Marvell. This CPU is currently found in
Armada 370 and Armada XP SoCs. This patch provides a support for the
specific initialization of this CPU.
Signed-off-by: Yehuda Yitschak <yehuday@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Flushing the cache is needed for the hardware to see the idmap table
and therefore can be done at init time. On ARMv7 it is not necessary to
flush L2 so flush_cache_louis() is used here instead.
There is no point flushing the cache in setup_mm_for_reboot() as the
caller should, and already is, taking care of this. If switching the
memory map requires a cache flush, then cpu_switch_mm() already includes
that operation.
What is not done by cpu_switch_mm() on ASID capable CPUs is TLB flushing
as the whole point of the ASID is to tag the TLBs and avoid flushing them
on a context switch. Since we don't have a clean ASID for the identity
mapping, we need to flush the TLB explicitly in that case. Otherwise
this is already performed by cpu_switch_mm().
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
PROT_NONE mappings apply the page protection attributes defined by _P000
which translate to PAGE_NONE for ARM. These attributes specify an XN,
RDONLY pte that is inaccessible to userspace. However, on kernels
configured without support for domains, such a pte *is* accessible to
the kernel and can be read via get_user, allowing tasks to read
PROT_NONE pages via syscalls such as read/write over a pipe.
This patch introduces a new software pte flag, L_PTE_NONE, that is set
to identify faulting, present entries.
Signed-off-by: Will Deacon <will.deacon@arm.com>
For long-descriptor translation table formats, the ARMv7 architecture
defines the last two bits of the second- and third-level descriptors to
be:
x0b - Invalid
01b - Block (second-level), Reserved (third-level)
11b - Table (second-level), Page (third-level)
This allows us to define L_PTE_PRESENT as (3 << 0) and use this value to
create ptes directly. However, when determining whether a given pte
value is present in the low-level page table accessors, we only need to
check the least significant bit of the descriptor, allowing us to write
faulting, present entries which are required for PROT_NONE mappings.
This patch introduces L_PTE_VALID, which can be used to test whether a
pte should fault, and updates the low-level page table accessors
accordingly.
Signed-off-by: Will Deacon <will.deacon@arm.com>
The simplified access permissions model is not used for the classic MMU
translation regime, so ensure that it is turned off in the sctlr prior
to turning on address translation for ARMv7.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
When updating the page protection map after calculating the user_pgprot
value, the base protection map is temporarily stored in an unsigned long
type, causing truncation of the protection bits when LPAE is enabled.
This effectively means that calls to mprotect() will corrupt the upper
page attributes, clearing the XN bit unconditionally.
This patch uses pteval_t to store the intermediate protection values,
preserving the upper bits for 64-bit descriptors.
Cc: stable@vger.kernel.org
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Aurora Cache Controller was designed to be compatible with the ARM L2
Cache Controller. It comes with some difference or improvement such
as:
- no cache id part number available through hardware (need to get it
by the DT).
- always write through mode available.
- two flavors of the controller outer cache and system cache (meaning
maintenance operations on L1 are broadcasted to the L2 and L2
performs the same operation).
- in outer cache mode, the cache maintenance operations are improved and
can be done on a range inside a page and are not limited to a cache
line.
Tested-and-Reviewed-by: Lior Amsalem <alior@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Yehuda Yitschak <yehuday@marvell.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When using DEBUG_LL, the UART's (or other HW's) registers are mapped
into early page tables based on the results of assembly macro addruart.
Later, when the page tables are replaced, the same virtual address must
remain valid. Historically, this has been ensured by using defines from
<mach/iomap.h> in both the implementation of addruart, and the machine's
.map_io() function. However, with the move to single zImage, we wish to
remove <mach/iomap.h>. To enable this, the macro addruart may be used
when constructing the late page tables too; addruart is exposed as a
C function debug_ll_addr(), and used to set up the required mapping in
debug_ll_io_init(), which may called on an opt-in basis from a machine's
.map_io() function.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
[swarren: Mask map.virtual with PAGE_MASK. Checked for NULL results from
debug_ll_addr (e.g. when selected UART isn't valid). Fixed compile when
either !CONFIG_DEBUG_LL or CONFIG_DEBUG_SEMIHOSTING.]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
When allocating a new ASID, we must take care not to re-assign a
reserved ASID-value to a new mm. This requires us to check each
candidate ASID against those currently reserved by other cores before
assigning a new ASID to the current mm.
This patch improves the ASID allocation algorithm by using a
bitmap-based approach. Rather than iterating over the reserved ASID
array for each candidate ASID, we simply find the first zero bit,
ensuring that those indices corresponding to reserved ASIDs are set
when flushing during a rollover event.
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
When scheduling a new mm, we take a spinlock so that we can:
1. Safely allocate a new ASID, if required
2. Update our active_asids field without worrying about parallel
updates to reserved_asids
3. Ensure that we flush our local TLB, if required
However, this has the nasty affect of serialising context-switch across
all CPUs in the system. The usual (fast) case is where the next mm has
a valid ASID for the current generation. In such a scenario, we can
avoid taking the lock and instead use atomic64_xchg to update the
active_asids variable for the current CPU. If a rollover occurs on
another CPU (which would take the lock), when copying the active_asids
into the reserved_asids another atomic64_xchg is used to replace each
active_asids with 0. The fast path can then detect this case and fall
back to spinning on the lock.
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
ASIDs are allocated to MMU contexts based on a rolling counter. This
means that after 255 allocations we must invalidate all existing ASIDs
via an expensive IPI mechanism to synchronise all of the online CPUs and
ensure that all tasks execute with an ASID from the new generation.
This patch changes the rollover behaviour so that we rely instead on the
hardware broadcasting of the TLB invalidation to avoid the IPI calls.
This works by keeping track of the active ASID on each core, which is
then reserved in the case of a rollover so that currently scheduled
tasks can continue to run. For cores without hardware TLB broadcasting,
we keep track of pending flushes in a cpumask, so cores can flush their
local TLB before scheduling a new mm.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The variables here are really not used uninitialized.
arch/arm/mm/alignment.c: In function 'do_alignment':
arch/arm/mm/alignment.c:327:15: warning: 'offset.un' may be used uninitialized in this function [-Wmaybe-uninitialized]
arch/arm/mm/alignment.c:748:21: note: 'offset.un' was declared here
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes the /dev/mem driver to use phys_addr_t for physical
addresses. This is required on PAE systems, especially those that run
entirely out of >4G physical memory space.
Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Marek Szyprowski