Changes in algos.c

19c000ba93d609e15e95fed76a9e3b8055833098 - raid6: use kmalloc() in raid6_select_algo()

Thu, 28 May 2026 11:53:01 +0200

raid6: use kmalloc() in raid6_select_algo()raid6_select_algo() allocates 8 pages for buffer that is usedas a scratch area for selection of the best algorithm.This buffer can be allocated with kmalloc() as there's nothing specialabout it to go directly to the page allocator.kmalloc() provides a better API than ancient __get_free_pages().kmalloc() does not require ugly casts and kfree() does not need to know thesize of the freed object.There is no performance difference because kmalloc() redirects allocationsof such size to the page allocator.Replace __get_free_pages() call with kmalloc().Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@redhat.comLink: https://lore.kernel.org/20260528-lib-v4-2-4e3ad1277279@kernel.orgSigned-off-by: Mike Rapoport (Microsoft) Reviewed-by: Christoph Hellwig Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Li Nan Cc: Song Liu Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

30bf04bd13a58cd9b877589569aa0abd06f04e52 - raid6: update top of file comments

Mon, 18 May 2026 07:17:56 +0200

raid6: update top of file commentsDrop the pointless mention of the file name, and use standard formattingfor the top of file comments.Link: https://lore.kernel.org/20260518051804.462141-14-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

dd83de0341da9979d6e584cd10e44361a183c938 - raid6: use static_call for raid6_recov_2data and raid6_recov_datap

Mon, 18 May 2026 07:17:55 +0200

raid6: use static_call for raid6_recov_2data and raid6_recov_datapAvoid expensive indirect calls for the recovery routines as well.Link: https://lore.kernel.org/20260518051804.462141-13-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

10f4b8e2a16452a7ead747c91a27ba3fabfe948d - raid6: use static_call for gen_syndrom and xor_syndrom

Mon, 18 May 2026 07:17:54 +0200

raid6: use static_call for gen_syndrom and xor_syndromAvoid indirect calls for P/Q parity generation.Link: https://lore.kernel.org/20260518051804.462141-12-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

adfcf6e89bc1322c4a6cc37ad32e411cf0500622 - raid6: rework registration of optimized algorithms

Mon, 18 May 2026 07:17:53 +0200

raid6: rework registration of optimized algorithmsReplace the static array of algorithms with a call to an architecturehelper to register algorithms. This serves two purposes: it avoid havingto register all algorithms in a single central place, and it removes theneed for the priority field by just registering the algorithms that thearchitecture considers suitable for the currently running CPUs.[hch@lst.de: register avx512 after avx2] Link: https://lore.kernel.org/20260527074539.2292913-3-hch@lst.deLink: https://lore.kernel.org/20260518051804.462141-11-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

769d603fc44f896e7f61de7f0cdb8b78d46bc8c8 - raid6: hide internals

Mon, 18 May 2026 07:17:52 +0200

raid6: hide internalsSplit out two new headers from the public pq.h: - lib/raid/raid6/algos.h contains the algorithm lists private to lib/raid/raid6 - include/linux/raid/pq_tables.h contains the tables also used by async_tx providers.The public include/linux/pq.h is now limited to the public interface forthe consumers of the RAID6 PQ API.[hch@lst.de: remove duplicate ccflags-y line] Link: https://lore.kernel.org/20260527074539.2292913-2-hch@lst.deLink: https://lore.kernel.org/20260518051804.462141-10-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

2790045a62eb52a5052eed06ddcc10b03b007a39 - raid6: warn when using less than four devices

Mon, 18 May 2026 07:17:51 +0200

raid6: warn when using less than four devicesQuoting H. Peter Anvin who came up with the RAID6 P/Q algorithm, and whowrote the initial implementation, then still part of the md driver: The RAID-6 code has *never* supported only 3 units, and if it ever worked for *any* of the implementations it was purely by accident. Speaking as the original author I should know; this was deliberate as in some cases the degenerate case (3) would have required extra trays in the code to no user benefit.While md never allowed less than 4 devices, btrfs does. This new warningwill trigger for such file systems, but given how it already causes havocthat is a good thing. If btrfs wants to fix third, it should switch totransparently use three-way mirroring underneath, which will work as P andQ are copies of the single data device by the definition of the Linux RAID6 P/Q algorithm.Link: https://lore.kernel.org/20260518051804.462141-9-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

35472bc6f31b64e58d1fe560340aa4f1684b8d6d - raid6: improve the public interface

Mon, 18 May 2026 07:17:50 +0200

raid6: improve the public interfaceStop directly calling into function pointers from users of the RAID6 PQAPI, and provide exported functions with proper documentation and APIguarantees asserts where applicable instead.Link: https://lore.kernel.org/20260518051804.462141-8-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c

3626738bc7147d52cb49f3994a9846aa2d34810a - raid6: move to lib/raid/

Mon, 18 May 2026 07:17:46 +0200

raid6: move to lib/raid/Move the raid6 code to live in lib/raid/ with the XOR code, and change theinternal organization so that each architecture has a subdirectory similarto the CRC, crypto and XOR libraries, and fix up the Makefile to onlybuild files actually needed.Also move the kunit test case from the history test/ subdirectory totests/ and use the normal naming scheme for it.Link: https://lore.kernel.org/20260518051804.462141-4-hch@lst.deSigned-off-by: Christoph Hellwig Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel # kunit only on arm64Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Li Nan Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Song Liu Cc: Sven Schnelle Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux/lib/raid/raid6/algos.c