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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Stat-Signature: 9ofru9wwegdpbmejra5n8eceypuktxnk X-Rspamd-Server: rspam09 X-Rspam-User: X-Rspamd-Queue-Id: 125EC40019 X-HE-Tag: 1773756693-388799 X-HE-Meta: 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 MaB8p1Fm 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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= 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 5856d35be385..869d79c8daa4 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= @@ -2793,8 +2784,18 @@ 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=