Commit Graph

30 Commits

Author SHA1 Message Date
Thomas Gleixner
caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
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 foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Will Deacon
33309ecda0 arm64: Fix minor issues with the dcache_by_line_op macro
The dcache_by_line_op macro suffers from a couple of small problems:

First, the GAS directives that are currently being used rely on
assembler behavior that is not documented, and probably not guaranteed
to produce the correct behavior going forward. As a result, we end up
with some undefined symbols in cache.o:

$ nm arch/arm64/mm/cache.o
         ...
         U civac
         ...
         U cvac
         U cvap
         U cvau

This is due to the fact that the comparisons used to select the
operation type in the dcache_by_line_op macro are comparing symbols
not strings, and even though it seems that GAS is doing the right
thing here (undefined symbols by the same name are equal to each
other), it seems unwise to rely on this.

Second, when patching in a DC CVAP instruction on CPUs that support it,
the fallback path consists of a DC CVAU instruction which may be
affected by CPU errata that require ARM64_WORKAROUND_CLEAN_CACHE.

Solve these issues by unrolling the various maintenance routines and
using the conditional directives that are documented as operating on
strings. To avoid the complexity of nested alternatives, we move the
DC CVAP patching to __clean_dcache_area_pop, falling back to a branch
to __clean_dcache_area_poc if DCPOP is not supported by the CPU.

Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10 15:03:51 +00:00
Will Deacon
3b8c9f1cdf arm64: IPI each CPU after invalidating the I-cache for kernel mappings
When invalidating the instruction cache for a kernel mapping via
flush_icache_range(), it is also necessary to flush the pipeline for
other CPUs so that instructions fetched into the pipeline before the
I-cache invalidation are discarded. For example, if module 'foo' is
unloaded and then module 'bar' is loaded into the same area of memory,
a CPU could end up executing instructions from 'foo' when branching into
'bar' if these instructions were fetched into the pipeline before 'foo'
was unloaded.

Whilst this is highly unlikely to occur in practice, particularly as
any exception acts as a context-synchronizing operation, following the
letter of the architecture requires us to execute an ISB on each CPU
in order for the new instruction stream to be visible.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 17:24:36 +01:00
Shanker Donthineni
6ae4b6e057 arm64: Add support for new control bits CTR_EL0.DIC and CTR_EL0.IDC
The DCache clean & ICache invalidation requirements for instructions
to be data coherence are discoverable through new fields in CTR_EL0.
The following two control bits DIC and IDC were defined for this
purpose. No need to perform point of unification cache maintenance
operations from software on systems where CPU caches are transparent.

This patch optimize the three functions __flush_cache_user_range(),
clean_dcache_area_pou() and invalidate_icache_range() if the hardware
reports CTR_EL0.IDC and/or CTR_EL0.IDC. Basically it skips the two
instructions 'DC CVAU' and 'IC IVAU', and the associated loop logic
in order to avoid the unnecessary overhead.

CTR_EL0.DIC: Instruction cache invalidation requirements for
 instruction to data coherence. The meaning of this bit[29].
  0: Instruction cache invalidation to the point of unification
     is required for instruction to data coherence.
  1: Instruction cache cleaning to the point of unification is
      not required for instruction to data coherence.

CTR_EL0.IDC: Data cache clean requirements for instruction to data
 coherence. The meaning of this bit[28].
  0: Data cache clean to the point of unification is required for
     instruction to data coherence, unless CLIDR_EL1.LoC == 0b000
     or (CLIDR_EL1.LoUIS == 0b000 && CLIDR_EL1.LoUU == 0b000).
  1: Data cache clean to the point of unification is not required
     for instruction to data coherence.

Co-authored-by: Philip Elcan <pelcan@codeaurora.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-09 13:57:57 +00:00
Christoffer Dall
0482b50546 arm64: mm: Add additional parameter to uaccess_ttbr0_disable
Add an extra temporary register parameter to uaccess_ttbr0_disable which
is about to be required for arm64 PAN support.

This patch doesn't introduce any functional change but ensures that the
kernel compiles once the KVM/ARM tree is merged with the arm64 tree by
ensuring a trivially mergable conflict with commit
6b88a32c7a
("arm64: kpti: Fix the interaction between ASID switching and software PAN").

Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-17 13:57:49 +01:00
Christoffer Dall
448fadc8a4 arm64: mm: Add additional parameter to uaccess_ttbr0_enable
Add an extra temporary register parameter to uaccess_ttbr0_enable which
is about to be required for arm64 PAN support.

This patch doesn't introduce any functional change but ensures that the
kernel compiles once the KVM/ARM tree is merged with the arm64 tree by
ensuring a trivially mergable conflict with commit
27a921e757
("arm64: mm: Fix and re-enable ARM64_SW_TTBR0_PAN").

Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-09 21:08:52 +01:00
Marc Zyngier
4fee947366 arm64: KVM: Add invalidate_icache_range helper
We currently tightly couple dcache clean with icache invalidation,
but KVM could do without the initial flush to PoU, as we've
already flushed things to PoC.

Let's introduce invalidate_icache_range which is limited to
invalidating the icache from the linear mapping (and thus
has none of the userspace fault handling complexity), and
wire it in KVM instead of flush_icache_range.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08 15:20:43 +01:00
Robin Murphy
d50e071fda arm64: Implement pmem API support
Add a clean-to-point-of-persistence cache maintenance helper, and wire
up the basic architectural support for the pmem driver based on it.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[catalin.marinas@arm.com: move arch_*_pmem() functions to arch/arm64/mm/flush.c]
[catalin.marinas@arm.com: change dmb(sy) to dmb(osh)]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-09 12:15:45 +01:00
Robin Murphy
d46befef4c arm64: Convert __inval_cache_range() to area-based
__inval_cache_range() is already the odd one out among our data cache
maintenance routines as the only remaining range-based one; as we're
going to want an invalidation routine to call from C code for the pmem
API, let's tweak the prototype and name to bring it in line with the
clean operations, and to make its relationship with __dma_inv_area()
neatly mirror that of __clean_dcache_area_poc() and __dma_clean_area().
The loop clearing the early page tables gets mildly massaged in the
process for the sake of consistency.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-09 11:00:23 +01:00
Al Viro
b4b8664d29 arm64: don't pull uaccess.h into *.S
Split asm-only parts of arm64 uaccess.h into a new header and use that
from *.S.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-26 13:05:17 -05:00
Linus Torvalds
7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Catalin Marinas
39bc88e5e3 arm64: Disable TTBR0_EL1 during normal kernel execution
When the TTBR0 PAN feature is enabled, the kernel entry points need to
disable access to TTBR0_EL1. The PAN status of the interrupted context
is stored as part of the saved pstate, reusing the PSR_PAN_BIT (22).
Restoring access to TTBR0_EL1 is done on exception return if returning
to user or returning to a context where PAN was disabled.

Context switching via switch_mm() must defer the update of TTBR0_EL1
until a return to user or an explicit uaccess_enable() call.

Special care needs to be taken for two cases where TTBR0_EL1 is set
outside the normal kernel context switch operation: EFI run-time
services (via efi_set_pgd) and CPU suspend (via cpu_(un)install_idmap).
Code has been added to avoid deferred TTBR0_EL1 switching as in
switch_mm() and restore the reserved TTBR0_EL1 when uninstalling the
special TTBR0_EL1.

User cache maintenance (user_cache_maint_handler and
__flush_cache_user_range) needs the TTBR0_EL1 re-instated since the
operations are performed by user virtual address.

This patch also removes a stale comment on the switch_mm() function.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-21 18:48:54 +00:00
Kwangwoo Lee
d34fdb7081 arm64: mm: convert __dma_* routines to use start, size
__dma_* routines have been converted to use start and size instread of
start and end addresses. The patch was origianlly for adding
__clean_dcache_area_poc() which will be used in pmem driver to clean
dcache to the PoC(Point of Coherency) in arch_wb_cache_pmem().

The functionality of __clean_dcache_area_poc()  was equivalent to
__dma_clean_range(). The difference was __dma_clean_range() uses the end
address, but __clean_dcache_area_poc() uses the size to clean.

Thus, __clean_dcache_area_poc() has been revised with a fallthrough
function of __dma_clean_range() after the change that __dma_* routines
use start and size instead of using start and end.

As a consequence of using start and size, the name of __dma_* routines
has also been altered following the terminology below:
    area: takes a start and size
    range: takes a start and end

Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Kwangwoo Lee <kwangwoo.lee@sk.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-22 10:00:48 +01:00
Andre Przywara
290622efc7 arm64: fix "dc cvau" cache operation on errata-affected core
The ARM errata 819472, 826319, 827319 and 824069 for affected
Cortex-A53 cores demand to promote "dc cvau" instructions to
"dc civac" as well.
Attribute the usage of the instruction in __flush_cache_user_range
to also be covered by our alternative patching efforts.
For that we introduce an assembly macro which both deals with
alternatives while still tagging the instructions as USER.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:26:20 +01:00
Geoff Levand
7b7293ae3d arm64: Fold proc-macros.S into assembler.h
To allow the assembler macros defined in arch/arm64/mm/proc-macros.S to
be used outside the mm code move the contents of proc-macros.S to
asm/assembler.h.  Also, delete proc-macros.S, and fix up all references
to proc-macros.S.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
[rebased, included dcache_by_line_op]
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-28 12:05:45 +01:00
Ashok Kumar
0a28714c53 arm64: Use PoU cache instr for I/D coherency
In systems with three levels of cache(PoU at L1 and PoC at L3),
PoC cache flush instructions flushes L2 and L3 caches which could affect
performance.
For cache flushes for I and D coherency, PoU should suffice.
So changing all I and D coherency related cache flushes to PoU.

Introduced a new __clean_dcache_area_pou API for dcache flush till PoU
and provided a common macro for __flush_dcache_area and
__clean_dcache_area_pou.

Also, now in __sync_icache_dcache, icache invalidation for non-aliasing
VIPT icache is done only for that particular page instead of the earlier
__flush_icache_all.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ashok Kumar <ashoks@broadcom.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 11:07:13 +00:00
Ard Biesheuvel
207918461e arm64: use ENDPIPROC() to annotate position independent assembler routines
For more control over which functions are called with the MMU off or
with the UEFI 1:1 mapping active, annotate some assembler routines as
position independent. This is done by introducing ENDPIPROC(), which
replaces the ENDPROC() declaration of those routines.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-12 16:19:45 +01:00
Daniel Thompson
271d35eb77 arm64: mm: Adopt new alternative assembler macros
Convert the dynamic patching for ARM64_WORKAROUND_CLEAN_CACHE over to
the newly added alternative assembler macros.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27 11:08:40 +01:00
Marc Zyngier
8d883b23ae arm64: alternative: Merge alternative-asm.h into alternative.h
asm/alternative-asm.h and asm/alternative.h are extremely similar,
and really deserve to live in the same file (as this makes further
modufications a bit easier).

Fold the content of alternative-asm.h into alternative.h, and
update the few users.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-06-05 10:38:53 +01:00
Mark Rutland
68234df4ea arm64: kill flush_cache_all()
The documented semantics of flush_cache_all are not possible to provide
for arm64 (short of flushing the entire physical address space by VA),
and there are currently no users; KVM uses VA maintenance exclusively,
cpu_reset is never called, and the only two users outside of arch code
cannot be built for arm64.

While cpu_soft_reset and related functions (which call flush_cache_all)
were thought to be useful for kexec, their current implementations only
serve to mask bugs. For correctness kexec will need to perform
maintenance by VA anyway to account for system caches, line migration,
and other subtleties of the cache architecture. As the extent of this
cache maintenance will be kexec-specific, it should probably live in the
kexec code.

This patch removes flush_cache_all, and related unused components,
preventing further abuse.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Geoff Levand <geoff@infradead.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-05-19 15:27:42 +01:00
Vladimir Murzin
a2d25a5391 arm64: compat: align cacheflush syscall with arch/arm
Update handling of cacheflush syscall with changes made in arch/arm
counterpart:
 - return error to userspace when flushing syscall fails
 - split user cache-flushing into interruptible chunks
 - don't bother rounding to nearest vma

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
[will: changed internal return value from -EINTR to 0 to match arch/arm/]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-01 13:31:12 +00:00
Andre Przywara
301bcfac42 arm64: add Cortex-A53 cache errata workaround
The ARM errata 819472, 826319, 827319 and 824069 define the same
workaround for these hardware issues in certain Cortex-A53 parts.
Use the new alternatives framework and the CPU MIDR detection to
patch "cache clean" into "cache clean and invalidate" instructions if
an affected CPU is detected at runtime.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
[will: add __maybe_unused to squash gcc warning]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:21 +00:00
Will Deacon
dc60b777fc arm64: mm: use inner-shareable barriers for inner-shareable maintenance
In order to ensure ordering and completion of inner-shareable maintenance
instructions (cache and TLB) on AArch64, we can use the -ish suffix to
the dmb and dsb instructions respectively.

This patch updates our low-level cache and tlb maintenance routines to
use the inner-shareable barrier variants where appropriate.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-09 17:21:24 +01:00
Catalin Marinas
ebf81a938d arm64: Fix DMA range invalidation for cache line unaligned buffers
If the buffer needing cache invalidation for inbound DMA does start or
end on a cache line aligned address, we need to use the non-destructive
clean&invalidate operation. This issue was introduced by commit
7363590d2c (arm64: Implement coherent DMA API based on swiotlb).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Jon Medhurst (Tixy) <tixy@linaro.org>
2014-04-08 11:45:08 +01:00
Catalin Marinas
c218bca74e arm64: Relax the kernel cache requirements for boot
With system caches for the host OS or architected caches for guest OS we
cannot easily guarantee that there are no dirty or stale cache lines for
the areas of memory written by the kernel during boot with the MMU off
(therefore non-cacheable accesses).

This patch adds the necessary cache maintenance during boot and relaxes
the booting requirements.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-04-05 10:06:18 +01:00
Mark Rutland
bff705950e arm64: remove unnecessary cache flush at boot
Currently we flush the entire dcache at boot within __cpu_setup, but
this is unnecessary as the booting protocol demands that the dcache is
invalid and off upon entering the kernel. The presence of the cache
flush only serves to hide bugs in bootloaders, and is not safe in the
presence of SMP.

In an SMP boot scenario the CPUs enter coherency outside of the kernel,
and the primary CPU enables its caches before bringing up secondary
CPUs. Therefore if any secondary CPU has an entry in its cache (in
violation of the boot protocol), the primary CPU might snoop it even if
the secondary CPU's cache is disabled. The boot-time cache flush only
serves to hide a firmware bug, and slows down a cpu boot unnecessarily.

This patch removes the unnecessary boot-time cache flush.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: make __flush_dcache_all local only]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-03-04 01:07:22 +00:00
Catalin Marinas
7363590d2c arm64: Implement coherent DMA API based on swiotlb
This patch adds support for DMA API cache maintenance on SoCs without
hardware device cache coherency.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-27 17:16:59 +00:00
Jingoo Han
03324e6e6e arm64: mm: fix the function name in comment of __flush_dcache_area
Fix the function name of comment of __flush_dcache_area,
because __flush_dcache_area is the correct name. Also,
the missing variable 'size' is added to the comment.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-01-22 16:24:19 +00:00
Sukanto Ghosh
b4fed07968 arm64: mm: Fix operands of clz in __flush_dcache_all
The format of the lower 32-bits of the 64-bit operand to 'dc cisw' is
unchanged from ARMv7 architecture and the upper bits are RES0. This
implies that the 'way' field of the operand of 'dc cisw' occupies the
bit-positions [31 .. (32-A)]. Due to the use of 64-bit extended operands
to 'clz', the existing implementation of __flush_dcache_all is incorrectly
placing the 'way' field in the bit-positions [63 .. (64-A)].

Signed-off-by: Sukanto Ghosh <sghosh@apm.com>
Tested-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@vger.kernel.org
2013-05-14 15:44:50 +01:00
Catalin Marinas
f1a0c4aa09 arm64: Cache maintenance routines
The patch adds functionality required for cache maintenance. The AArch64
architecture mandates non-aliasing VIPT or PIPT D-cache and VIPT (may
have aliases) or ASID-tagged VIVT I-cache. Cache maintenance operations
are automatically broadcast in hardware between CPUs.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-09-17 13:42:00 +01:00