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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Stat-Signature: eojy68wh58cd6pkr31uwthmkcghkeixx X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: CE7454000F X-HE-Tag: 1769446078-863850 X-HE-Meta: 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 2rah/k9L HN8DMVDa+mYmQQf+RT1YVjkYl8JVlcDtKJ0pZhvJPS98Vq0FyQMNWQGNJta5CZAWxfJ+F5CXMZm2elUB4oF2J/VPA2blkQThgh3a4NPblzNvaMFMbO4hiH7d8FHGfIOp89wg7DS6pJdAKiKg3UYQw0KsTCvbbkIgiWVGErRHcHHK6PtkbilUfULwbBddo7FuhkkYdmYtQMfKB1WyG0R+g1agncHhsHKI+AH4M1hjY+JKH9t1ENOncgajvPQnRgZR5uDwIY9hazbTj4mIg3PZDYf5NrLNPxnzlEF5U0hJtv9TkSN540p92CQ6Bj1NvahR3BqwluyXm7pX8vFc7gs8hiLoGY1SiQ2VU/KTyKXgjlNuOL/p4eGuls406B7BDODCcXV7/FzJ/ua4U07vPm+JX2FhCGbO8e/eK/+yFn+8kBWy+mod3DihmyUmacj7ZxD5vLU30p5PlZd4BoBVyT5EWF/D5dvVlH7C3pPCozyn6t+oZiQOOqPGBc3yY9vf3HunwDDzMxWF2q7lhqHqcZ7ymLOKlk2lolgV8Shyw5sx8DsEmbhjX7+dSxfTNylSzPNztU8rYez4Zpd6Bqt/l8FQQ1vb4MAPpk4CZ1XyS/9L/M/iJDovTtTWrzZUsXYGCnMVC+uyGkVHZ10cuGXGZUl3EzCarZ6fIgqAJl7gDaiL/YU68jEYX48EAX7PxHTBY/h70goXoZ0HoF86I3Le9oLae8nSdCF9Mj2DVoU5q873u3/lSXwwIX9f97GHcocQZ9PoAtF1tan0SYM9iW2k= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 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 | 19 ++++++++-----------=0A= 1 file changed, 8 insertions(+), 11 deletions(-)=0A= =0A= diff --git a/mm/gup.c b/mm/gup.c=0A= index 9cad53acbc99..e72dacce3e34 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 +2784,14 @@ 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 long term= =0A= + * pin is the most egregious case so this is the one we disallow.=0A= + * Also check the only remaining allowed file system - shmem.=0A= + */=0A= + return (flags & (FOLL_PIN | FOLL_LONGTERM | FOLL_WRITE)) !=3D=0A= + (FOLL_PIN | FOLL_LONGTERM | FOLL_WRITE) || shmem_mapping(mapping);=0A= }=0A= =0A= static void __maybe_unused gup_fast_undo_dev_pagemap(int *nr, int nr_start= ,=0A= -- =0A= 2.50.1=0A= =0A=