From: Mike Rapoport <rppt@kernel.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>,
Axel Rasmussen <axelrasmussen@google.com>,
Baolin Wang <baolin.wang@linux.alibaba.com>,
David Hildenbrand <david@kernel.org>,
Hugh Dickins <hughd@google.com>,
James Houghton <jthoughton@google.com>,
"Liam R. Howlett" <Liam.Howlett@oracle.com>,
Lorenzo Stoakes <lorenzo.stoakes@oracle.com>,
"Matthew Wilcox (Oracle)" <willy@infradead.org>,
Michal Hocko <mhocko@suse.com>, Mike Rapoport <rppt@kernel.org>,
Muchun Song <muchun.song@linux.dev>,
Nikita Kalyazin <kalyazin@amazon.com>,
Oscar Salvador <osalvador@suse.de>,
Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>,
Sean Christopherson <seanjc@google.com>,
Shuah Khan <shuah@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Vlastimil Babka <vbabka@suse.cz>,
kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
linux-mm@kvack.org
Subject: [PATCH v2 06/15] userfaultfd: move vma_can_userfault out of line
Date: Fri, 6 Mar 2026 19:18:06 +0200 [thread overview]
Message-ID: <20260306171815.3160826-7-rppt@kernel.org> (raw)
In-Reply-To: <20260306171815.3160826-1-rppt@kernel.org>
From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
vma_can_userfault() has grown pretty big and it's not called on
performance critical path.
Move it out of line.
No functional changes.
Reviewed-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
include/linux/userfaultfd_k.h | 35 ++---------------------------------
mm/userfaultfd.c | 33 +++++++++++++++++++++++++++++++++
2 files changed, 35 insertions(+), 33 deletions(-)
diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h
index fd5f42765497..a49cf750e803 100644
--- a/include/linux/userfaultfd_k.h
+++ b/include/linux/userfaultfd_k.h
@@ -208,39 +208,8 @@ static inline bool userfaultfd_armed(struct vm_area_struct *vma)
return vma->vm_flags & __VM_UFFD_FLAGS;
}
-static inline bool vma_can_userfault(struct vm_area_struct *vma,
- vm_flags_t vm_flags,
- bool wp_async)
-{
- vm_flags &= __VM_UFFD_FLAGS;
-
- if (vma->vm_flags & VM_DROPPABLE)
- return false;
-
- if ((vm_flags & VM_UFFD_MINOR) &&
- (!is_vm_hugetlb_page(vma) && !vma_is_shmem(vma)))
- return false;
-
- /*
- * If wp async enabled, and WP is the only mode enabled, allow any
- * memory type.
- */
- if (wp_async && (vm_flags == VM_UFFD_WP))
- return true;
-
- /*
- * If user requested uffd-wp but not enabled pte markers for
- * uffd-wp, then shmem & hugetlbfs are not supported but only
- * anonymous.
- */
- if (!uffd_supports_wp_marker() && (vm_flags & VM_UFFD_WP) &&
- !vma_is_anonymous(vma))
- return false;
-
- /* By default, allow any of anon|shmem|hugetlb */
- return vma_is_anonymous(vma) || is_vm_hugetlb_page(vma) ||
- vma_is_shmem(vma);
-}
+bool vma_can_userfault(struct vm_area_struct *vma, vm_flags_t vm_flags,
+ bool wp_async);
static inline bool vma_has_uffd_without_event_remap(struct vm_area_struct *vma)
{
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 828f252c720c..c5fd1e5c67b3 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -2020,6 +2020,39 @@ ssize_t move_pages(struct userfaultfd_ctx *ctx, unsigned long dst_start,
return moved ? moved : err;
}
+bool vma_can_userfault(struct vm_area_struct *vma, vm_flags_t vm_flags,
+ bool wp_async)
+{
+ vm_flags &= __VM_UFFD_FLAGS;
+
+ if (vma->vm_flags & VM_DROPPABLE)
+ return false;
+
+ if ((vm_flags & VM_UFFD_MINOR) &&
+ (!is_vm_hugetlb_page(vma) && !vma_is_shmem(vma)))
+ return false;
+
+ /*
+ * If wp async enabled, and WP is the only mode enabled, allow any
+ * memory type.
+ */
+ if (wp_async && (vm_flags == VM_UFFD_WP))
+ return true;
+
+ /*
+ * If user requested uffd-wp but not enabled pte markers for
+ * uffd-wp, then shmem & hugetlbfs are not supported but only
+ * anonymous.
+ */
+ if (!uffd_supports_wp_marker() && (vm_flags & VM_UFFD_WP) &&
+ !vma_is_anonymous(vma))
+ return false;
+
+ /* By default, allow any of anon|shmem|hugetlb */
+ return vma_is_anonymous(vma) || is_vm_hugetlb_page(vma) ||
+ vma_is_shmem(vma);
+}
+
static void userfaultfd_set_vm_flags(struct vm_area_struct *vma,
vm_flags_t vm_flags)
{
--
2.51.0
next prev parent reply other threads:[~2026-03-06 17:19 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-06 17:18 [PATCH v2 00/15] mm, kvm: allow uffd support in guest_memfd Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 01/15] userfaultfd: introduce mfill_copy_folio_locked() helper Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 02/15] userfaultfd: introduce struct mfill_state Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 03/15] userfaultfd: introduce mfill_get_pmd() helper Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 04/15] userfaultfd: introduce mfill_get_vma() and mfill_put_vma() Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 05/15] userfaultfd: retry copying with locks dropped in mfill_atomic_pte_copy() Mike Rapoport
2026-03-06 17:18 ` Mike Rapoport [this message]
2026-03-06 17:18 ` [PATCH v2 07/15] userfaultfd: introduce vm_uffd_ops Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 08/15] shmem, userfaultfd: use a VMA callback to handle UFFDIO_CONTINUE Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 09/15] userfaultfd: introduce vm_uffd_ops->alloc_folio() Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 10/15] shmem, userfaultfd: implement shmem uffd operations using vm_uffd_ops Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 11/15] userfaultfd: mfill_atomic(): remove retry logic Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 12/15] mm: generalize handling of userfaults in __do_fault() Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 13/15] KVM: guest_memfd: implement userfaultfd operations Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 14/15] KVM: selftests: test userfaultfd minor for guest_memfd Mike Rapoport
2026-03-06 17:18 ` [PATCH v2 15/15] KVM: selftests: test userfaultfd missing " Mike Rapoport
2026-03-06 22:21 ` [PATCH v2 00/15] mm, kvm: allow uffd support in guest_memfd Andrew Morton
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260306171815.3160826-7-rppt@kernel.org \
--to=rppt@kernel.org \
--cc=Liam.Howlett@oracle.com \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=axelrasmussen@google.com \
--cc=baolin.wang@linux.alibaba.com \
--cc=david@kernel.org \
--cc=hughd@google.com \
--cc=jthoughton@google.com \
--cc=kalyazin@amazon.com \
--cc=kvm@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=lorenzo.stoakes@oracle.com \
--cc=mhocko@suse.com \
--cc=muchun.song@linux.dev \
--cc=osalvador@suse.de \
--cc=pbonzini@redhat.com \
--cc=peterx@redhat.com \
--cc=seanjc@google.com \
--cc=shuah@kernel.org \
--cc=surenb@google.com \
--cc=vbabka@suse.cz \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox