mm: hugetlb: Add huge page size param to huge_ptep_get_and_clear()

commit 02410ac72ac3707936c07ede66e94360d0d65319 upstream.

In order to fix a bug, arm64 needs to be told the size of the huge page

mm: hugetlb: Add huge page size param to huge_ptep_get_and_clear()

commit 02410ac72ac3707936c07ede66e94360d0d65319 upstream.

In order to fix a bug, arm64 needs to be told the size of the huge page
for which the huge_pte is being cleared in huge_ptep_get_and_clear().
Provide for this by adding an `unsigned long sz` parameter to the
function. This follows the same pattern as huge_pte_clear() and
set_huge_pte_at().

This commit makes the required interface modifications to the core mm as
well as all arches that implement this function (arm64, loongarch, mips,
parisc, powerpc, riscv, s390, sparc). The actual arm64 bug will be fixed
in a separate commit.

Cc: stable@vger.kernel.org
Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit")
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> # s390
Link: https://lore.kernel.org/r/20250226120656.2400136-2-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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s390/pageattr: Implement missing kernel_page_present()

[ Upstream commit 2835f8bf5530750c3381166005934f996a83ad05 ]

kernel_page_present() was intentionally not implemented when adding
ARCH_HAS_SET_

s390/pageattr: Implement missing kernel_page_present()

[ Upstream commit 2835f8bf5530750c3381166005934f996a83ad05 ]

kernel_page_present() was intentionally not implemented when adding
ARCH_HAS_SET_DIRECT_MAP support, since it was only used for suspend/resume
which is not supported anymore on s390.

A new bpf use case led to a compile error specific to s390. Even though
this specific use case went away implement kernel_page_present(), so that
the API is complete and potential future users won't run into this problem.

Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Closes: https://lore.kernel.org/all/045de961-ac69-40cc-b141-ab70ec9377ec@iogearbox.net
Fixes: 0490d6d7ba0a ("s390/mm: enable ARCH_HAS_SET_DIRECT_MAP")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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s390/mm: Add cond_resched() to cmm_alloc/free_pages()

[ Upstream commit 131b8db78558120f58c5dc745ea9655f6b854162 ]

Adding/removing large amount of pages at once to/from the CMM balloon
can result i

s390/mm: Add cond_resched() to cmm_alloc/free_pages()

[ Upstream commit 131b8db78558120f58c5dc745ea9655f6b854162 ]

Adding/removing large amount of pages at once to/from the CMM balloon
can result in rcu_sched stalls or workqueue lockups, because of busy
looping w/o cond_resched().

Prevent this by adding a cond_resched(). cmm_free_pages() holds a
spin_lock while looping, so it cannot be added directly to the existing
loop. Instead, introduce a wrapper function that operates on maximum 256
pages at once, and add it there.

Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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