mm: constify arch_pick_mmap_layout() for improved const-correctness

This function only reads from the rlimit pointer (but writes to the
mm_struct pointer which is kept without `const`).

All callees are already const-ified or (internal functions) are being
constified by this patch.

Link: https://lkml.kernel.org/r/20250901205021.3573313-9-max.kellermann@ionos.com
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christian Zankel <chris@zankel.net>
Cc: David Rientjes <rientjes@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Bottomley <james.bottomley@HansenPartnership.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jocelyn Falempe <jfalempe@redhat.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Nysal Jan K.A" <nysal@linux.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russel King <linux@armlinux.org.uk>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Thomas Huth <thuth@redhat.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/mm/util.c b/mm/util.c
index 391f6e7daf83..732a2dfcaec7 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -431,7 +431,7 @@ static int mmap_is_legacy(const struct rlimit *rlim_stack)
 #define MIN_GAP		(SZ_128M)
 #define MAX_GAP		(STACK_TOP / 6 * 5)
 
-static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack)
+static unsigned long mmap_base(const unsigned long rnd, const struct rlimit *rlim_stack)
 {
 #ifdef CONFIG_STACK_GROWSUP
 	/*
@@ -462,7 +462,7 @@ static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack)
 #endif
 }
 
-void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
+void arch_pick_mmap_layout(struct mm_struct *mm, const struct rlimit *rlim_stack)
 {
 	unsigned long random_factor = 0UL;
 
@@ -478,7 +478,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 	}
 }
 #elif defined(CONFIG_MMU) && !defined(HAVE_ARCH_PICK_MMAP_LAYOUT)
-void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
+void arch_pick_mmap_layout(struct mm_struct *mm, const struct rlimit *rlim_stack)
 {
 	mm->mmap_base = TASK_UNMAPPED_BASE;
 	mm_flags_clear(MMF_TOPDOWN, mm);