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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Queue-Id: 2C16DC000A X-Stat-Signature: kf79uup9y39hgokw7yemimssz8aaycny X-Rspamd-Server: rspam06 X-HE-Tag: 1775834326-698692 X-HE-Meta: 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 9uO2dGmE 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Nikita Kalyazin =0A= =0A= Move the check for pinning closer to where the result is used.=0A= No functional changes.=0A= =0A= Acked-by: David Hildenbrand (Arm) =0A= Signed-off-by: Nikita Kalyazin =0A= ---=0A= mm/gup.c | 23 ++++++++++++-----------=0A= 1 file changed, 12 insertions(+), 11 deletions(-)=0A= =0A= diff --git a/mm/gup.c b/mm/gup.c=0A= index e8367564d636..41eb64783e03 100644=0A= --- a/mm/gup.c=0A= +++ b/mm/gup.c=0A= @@ -2737,18 +2737,9 @@ EXPORT_SYMBOL(get_user_pages_unlocked);=0A= */=0A= static bool gup_fast_folio_allowed(struct folio *folio, unsigned int flags= )=0A= {=0A= - bool reject_file_backed =3D false;=0A= struct address_space *mapping;=0A= unsigned long mapping_flags;=0A= =0A= - /*=0A= - * If we aren't pinning then no problematic write can occur. A long term= =0A= - * pin is the most egregious case so this is the one we disallow.=0A= - */=0A= - if ((flags & (FOLL_PIN | FOLL_LONGTERM | FOLL_WRITE)) =3D=3D=0A= - (FOLL_PIN | FOLL_LONGTERM | FOLL_WRITE))=0A= - reject_file_backed =3D true;=0A= -=0A= /* We hold a folio reference, so we can safely access folio fields. */=0A= if (WARN_ON_ONCE(folio_test_slab(folio)))=0A= return false;=0A= @@ -2797,8 +2788,18 @@ static bool gup_fast_folio_allowed(struct folio *fol= io, unsigned int flags)=0A= */=0A= if (secretmem_mapping(mapping))=0A= return false;=0A= - /* The only remaining allowed file system is shmem. */=0A= - return !reject_file_backed || shmem_mapping(mapping);=0A= +=0A= + /*=0A= + * If we aren't pinning then no problematic write can occur. A writable= =0A= + * long term pin is the most egregious case, so this is the one we=0A= + * allow only for ...=0A= + */=0A= + if ((flags & (FOLL_PIN | FOLL_LONGTERM | FOLL_WRITE)) !=3D=0A= + (FOLL_PIN | FOLL_LONGTERM | FOLL_WRITE))=0A= + return true;=0A= +=0A= + /* ... hugetlb (which we allowed above already) and shared memory. */=0A= + return shmem_mapping(mapping);=0A= }=0A= =0A= #ifdef CONFIG_ARCH_HAS_PTE_SPECIAL=0A= -- =0A= 2.50.1=0A= =0A=