[merged mm-stable] mm-secretmem-convert-to-mmap_prepare-hook.patch removed from -mm tree

[merged mm-stable] mm-secretmem-convert-to-mmap_prepare-hook.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm: secretmem: convert to .mmap_prepare() hook
has been removed from the -mm tree.  Its filename was
     mm-secretmem-convert-to-mmap_prepare-hook.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Subject: mm: secretmem: convert to .mmap_prepare() hook
Date: Fri, 9 May 2025 13:13:35 +0100

Secretmem has a simple .mmap() hook which is easily converted to the new
.mmap_prepare() callback.

Importantly, it's a rare instance of an driver that manipulates a VMA
which is mergeable (that is, not a VM_SPECIAL mapping) while also
adjusting VMA flags which may adjust mergeability, meaning the retry merge
logic might impact whether or not the VMA is merged.

By using .mmap_prepare() there's no longer any need to retry the merge
later as we can simply set the correct flags from the start.

This change therefore allows us to remove the retry merge logic in a
subsequent commit.

Link: https://lkml.kernel.org/r/0f758474fa6a30197bdf25ba62f898a69d84eef3.1746792520.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/secretmem.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

--- a/mm/secretmem.c~mm-secretmem-convert-to-mmap_prepare-hook
+++ a/mm/secretmem.c
@@ -120,18 +120,18 @@ static int secretmem_release(struct inod
 	return 0;
 }
 
-static int secretmem_mmap(struct file *file, struct vm_area_struct *vma)
+static int secretmem_mmap_prepare(struct vm_area_desc *desc)
 {
-	unsigned long len = vma->vm_end - vma->vm_start;
+	const unsigned long len = desc->end - desc->start;
 
-	if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
+	if ((desc->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
 		return -EINVAL;
 
-	if (!mlock_future_ok(vma->vm_mm, vma->vm_flags | VM_LOCKED, len))
+	if (!mlock_future_ok(desc->mm, desc->vm_flags | VM_LOCKED, len))
 		return -EAGAIN;
 
-	vm_flags_set(vma, VM_LOCKED | VM_DONTDUMP);
-	vma->vm_ops = &secretmem_vm_ops;
+	desc->vm_flags |= VM_LOCKED | VM_DONTDUMP;
+	desc->vm_ops = &secretmem_vm_ops;
 
 	return 0;
 }
@@ -143,7 +143,7 @@ bool vma_is_secretmem(struct vm_area_str
 
 static const struct file_operations secretmem_fops = {
 	.release	= secretmem_release,
-	.mmap		= secretmem_mmap,
+	.mmap_prepare	= secretmem_mmap_prepare,
 };
 
 static int secretmem_migrate_folio(struct address_space *mapping,
_

Patches currently in -mm which might be from lorenzo.stoakes@oracle.com are

maintainers-update-page-allocator-section.patch
maintainers-add-mm-reclaim-section.patch