[PATCH v9 0/4] Consolidate IO memcpy functions

From: Julian Vetter
Date: Thu Oct 10 2024 - 08:37:12 EST


Thank you for your remarks Arnd and Christoph. You're right the patches
got a bit out of hand. I have now guarded the prototypes as well with
'#ifndef' and I have dropped the other unnecessary patches for now.

Thank you Niklas for testing the changes on s390! I have dropped the
according patch for now. But I will send it to the s390 mailinglist as a
separate patch.

Thank you Takashi for ack'ing the patch 14. I will send this one as well
as a separate patch to the UM mailinglist.

Signed-off-by: Julian Vetter <jvetter@xxxxxxxxxxxxx>
---
Changes for v9:
- Moved functions into a new file iomem_copy.c which is built
unconditionally
- Guard prototypes with '#ifndef memcpy_fromio', etc.
- Dropped patches 5 to 14 for now. I will send some of the changes in
separate patches or patchsets to the appropriate mailinglists
- Added proper reviewed-by and acked-by to arm64 and csky patches

Changes for v8:
- Dropped the arch/um patch that adds dummy implementations for IO
memcpy functions
- Added 3 new patches that fix the dependency problem for UM (added
dependencies on HAS_IOMEM || INDIRECT_IOMEM)
- Added new patch for s390 to internally call the zpci_memcpy functions
and not the generic ones from libs/iomap_copy.c
- Addressed reviewer comments and replaced 2 or 3 shifts by
'qc *= ~0UL / 0xff;'
- Addressed reviewer comments on pasrisc (masking the int value)
- Addressed reviewer comments on alpha (masking the int value)

Changes for v7:
- Added dummy implementations for memcpy_{to,from}io and memset_io on um
architecture so drivers that use these functions build for um
- Replaced all accesses and checks by long type
- Added function prototypes as extern to asm-generic/io.h
- Removed '__' from the 3 new function names
- Some archs implement their own version of these IO functions with
slightly different prototypes. So, I added 3 new patches to align
prototypes with new ones in iomap_copy.c + io.h

Changes for v6:
- Added include of linux/align.h to fix build on arm arch
- Replaced compile-time check by ifdef for the CONFIG_64BIT otherwise we
get a warning for the 'qc << 32' for archs with 32bit int types
- Suffixed arch commits by arch name

Changes for v5:
- Added functions to iomap_copy.c as proposed by Arndt
- Removed again the new io_copy.c and related objects
- Removed GENERIC_IO_COPY symbol and instead rely on the existing
HAS_IOMEM symbol
- Added prototypes of __memcpy_{to,from}io and __memset_io functions to
asm-generic/io.h

Changes for v4:
- Replaced memcpy/memset in asm-generic/io.h by the new
__memcpy_{to,from}io and __memset_io, so individual architectures can
use it instead of using their own implementation.

Changes for v3:
- Replaced again 'if(IS_ENABLED(CONFIG_64BIT))' by '#ifdef CONFIG_64BIT'
because on 32bit architectures (e.g., csky), __raw_{read,write}q are
not defined. So, it leads to compilation errors

Changes for v2:
- Renamed io.c -> io_copy.c
- Updated flag to 'GENERIC_IO_COPY'
- Replaced pointer dereferences by 'put_unaligned()'/'get_unaligned()'
- Replaced '#ifdef CONFIG_64BIT' by 'if(IS_ENABLED(CONFIG_64BIT))'
- Removed '__raw_{read,write}_native' and replaced by
'if(IS_ENABLED(CONFIG_64BIT))' -> '__raw_write{l,q}'
---
Julian Vetter (4):
Consolidate IO memcpy/memset into iomem_copy.c
arm64: Use generic IO memcpy/memset
csky: Use generic IO memcpy/memset
loongarch: Use generic IO memcpy/memset

arch/arm64/include/asm/io.h | 11 ---
arch/arm64/kernel/io.c | 87 ---------------------
arch/csky/include/asm/io.h | 11 ---
arch/csky/kernel/Makefile | 2 +-
arch/csky/kernel/io.c | 91 ----------------------
arch/loongarch/include/asm/io.h | 10 ---
arch/loongarch/kernel/Makefile | 2 +-
arch/loongarch/kernel/io.c | 94 ----------------------
include/asm-generic/io.h | 62 +++------------
lib/Makefile | 2 +-
lib/iomem_copy.c | 134 ++++++++++++++++++++++++++++++++
11 files changed, 147 insertions(+), 359 deletions(-)
delete mode 100644 arch/csky/kernel/io.c
delete mode 100644 arch/loongarch/kernel/io.c
create mode 100644 lib/iomem_copy.c

--
2.34.1