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[2003:dc:6f1d:f00:230:64ff:fe74:809]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-afefcbd8656sm597512566b.56.2025.08.31.02.39.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 31 Aug 2025 02:39:35 -0700 (PDT) From: Max Kellermann To: akpm@linux-foundation.org, david@redhat.com, axelrasmussen@google.com, yuanchu@google.com, willy@infradead.org, hughd@google.com, mhocko@suse.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, vishal.moola@gmail.com Cc: Max Kellermann Subject: [PATCH v2 00/12] mm: add `const` to lots of pointer parameters Date: Sun, 31 Aug 2025 11:39:06 +0200 Message-ID: <20250831093918.2815332-1-max.kellermann@ionos.com> X-Mailer: git-send-email 2.47.2 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit For improved const-correctness. This work was initially posted here: https://lore.kernel.org/lkml/20250827192233.447920-1-max.kellermann@ionos.com/ .. but got rejected by Lorenzo Stoakes: https://lore.kernel.org/lkml/d6bf808d-7d74-4e22-ac4b-a6d1f4892262@lucifer.local/ David Hildenbrand and Lorenzo Stoakes suggested splitting the patch into smaller chunks. My second attempt with one smaller patch was met with agreement: https://lore.kernel.org/lkml/20250828130311.772993-1-max.kellermann@ionos.com/ Now this is the rest of the initial patch in small pieces, plus some more. Establishing const-correctness in this low-level part of the kernel enables doing the same in higher-level parts, e.g. filesystems. Signed-off-by: Max Kellermann --- v1-> v2: - made several parameter values const (i.e. the pointer address, not just the pointed-to memory), as suggested by Andrew Morton and Yuanchu Xie - drop existing+obsolete "extern" keywords on lines modified by these patches (suggested by Vishal Moola) - add missing parameter names on lines modified by these patches (suggested by Vishal Moola) - more "const" pointers (e.g. the task_struct passed to process_shares_mm()) - add missing "const" to s390, fixing s390 build failure - moved the mmap_is_legacy() change in arch/s390/mm/mmap.c from 08/12 to 06/12 (suggested by Vishal Moola) Max Kellermann (12): mm/shmem: add `const` to lots of pointer parameters include/pagemap.h: add `const` to lots of pointer parameters include/mmzone.h: add `const` to lots of pointer parameters include/fs.h: add `const` to several pointer parameters mm/oom_kill: add `const` to pointer parameter mm/util: add `const` to several pointer parameters parisc/sys_parisc.c: add `const` to mmap_upper_limit() parameter arch, mm/util: add const to arch_pick_mmap_layout() parameter include/mm_types.h: add `const` to several pointer parameters include/mm_inline.h: add `const` to lots of pointer parameters include/mm.h: add `const` to lots of pointer parameters mm/highmem: add `const` to lots of pointer parameters arch/arm/include/asm/highmem.h | 6 +-- arch/parisc/include/asm/processor.h | 2 +- arch/parisc/kernel/sys_parisc.c | 2 +- arch/s390/mm/mmap.c | 7 ++-- arch/sparc/kernel/sys_sparc_64.c | 5 ++- arch/x86/mm/mmap.c | 7 ++-- arch/xtensa/include/asm/highmem.h | 2 +- include/linux/fs.h | 7 ++-- include/linux/highmem-internal.h | 38 ++++++++++--------- include/linux/highmem.h | 8 ++-- include/linux/mm.h | 48 +++++++++++------------ include/linux/mm_inline.h | 26 +++++++------ include/linux/mm_types.h | 4 +- include/linux/mmzone.h | 42 ++++++++++---------- include/linux/pagemap.h | 59 +++++++++++++++-------------- include/linux/sched/mm.h | 4 +- include/linux/shmem_fs.h | 4 +- mm/highmem.c | 10 ++--- mm/oom_kill.c | 3 +- mm/shmem.c | 6 +-- mm/util.c | 20 ++++++---- 21 files changed, 163 insertions(+), 147 deletions(-) -- 2.47.2