linux.git/lib/raid/raid6, branch v7.2-rc1

raid6: use kmalloc() in raid6_select_algo()

2026-06-04T21:49:28+00:00

raid6_select_algo() allocates 8 pages for buffer that is used
as a scratch area for selection of the best algorithm.

This buffer can be allocated with kmalloc() as there's nothing special
about 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 the
size of the freed object.

There is no performance difference because kmalloc() redirects allocations
of 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.com
Link: https://lore.kernel.org/20260528-lib-v4-2-4e3ad1277279@kernel.org
Signed-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

raid6_kunit: randomize buffer alignment

2026-05-29T04:24:56+00:00

Add code to add random alignment to the buffers to test the case where
they are not page aligned, and to move the buffers to the end of the
allocation so that they are next to the vmalloc guard page.

This does not include the recovery buffers as the recovery requires page
alignment.

Link: https://lore.kernel.org/20260518051804.462141-19-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6_kunit: randomize parameters and increase limits

2026-05-29T04:24:56+00:00

The current test has double-quadratic behavior in the selection for the
updated ("XORed") disks, and in the selection of updated pointers, which
makes scaling it to more tests difficult.  At the same time it only ever
tests with the maximum number of disks, which leaves a coverage hole for
smaller ones.

Fix this by randomizing the total number, failed disks and regions to
update, and increasing the upper number of tests disks.

Link: https://lore.kernel.org/20260518051804.462141-18-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6_kunit: cleanup dataptr handling

2026-05-29T04:24:56+00:00

Move the global dataptr array into test_recover() as all sites that fill
data or parity can use test_buffers directly, and this localized the
override for the failed slots to the recovery testing routine.

Link: https://lore.kernel.org/20260518051804.462141-17-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6_kunit: dynamically allocate data buffers using vmalloc

2026-05-29T04:24:56+00:00

Use vmalloc for the data buffers instead of using static .data
allocations.  This provides for better out of bounds checking and avoids
wasting kernel memory after the test has run.  vmalloc is used instead of
kmalloc to provide for better out of bounds access checking as in other
kunit tests.

Link: https://lore.kernel.org/20260518051804.462141-16-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6_kunit: use KUNIT_CASE_PARAM

2026-05-29T04:24:55+00:00

The raid6 test combines various generation and recovery algorithms.  Use
KUNIT_CASE_PARAM and provide a generator that iterates over the possible
combinations instead of looping inside a single test instance.

Link: https://lore.kernel.org/20260518051804.462141-15-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6: update top of file comments

2026-05-29T04:24:55+00:00

Drop the pointless mention of the file name, and use standard formatting
for the top of file comments.

Link: https://lore.kernel.org/20260518051804.462141-14-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6: use static_call for raid6_recov_2data and raid6_recov_datap

2026-05-29T04:24:55+00:00

Avoid expensive indirect calls for the recovery routines as well.

Link: https://lore.kernel.org/20260518051804.462141-13-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6: use static_call for gen_syndrom and xor_syndrom

2026-05-29T04:24:55+00:00

Avoid indirect calls for P/Q parity generation.

Link: https://lore.kernel.org/20260518051804.462141-12-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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

raid6: rework registration of optimized algorithms

2026-05-29T04:24:54+00:00

Replace the static array of algorithms with a call to an architecture
helper to register algorithms.  This serves two purposes: it avoid having
to register all algorithms in a single central place, and it removes the
need for the priority field by just registering the algorithms that the
architecture considers suitable for the currently running CPUs.

[hch@lst.de: register avx512 after avx2]
  Link: https://lore.kernel.org/20260527074539.2292913-3-hch@lst.de
Link: https://lore.kernel.org/20260518051804.462141-11-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # kunit only on arm64
Cc: 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