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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, Liam Howlett Subject: [PATCH v6 08/14] mm/huge_memory: remove folio split check for READ_ONLY_THP_FOR_FS Date: Sun, 17 May 2026 09:54:10 -0400 Message-ID: <20260517135416.1434539-9-ziy@nvidia.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260517135416.1434539-1-ziy@nvidia.com> References: <20260517135416.1434539-1-ziy@nvidia.com> Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: YQ1P288CA0016.CANP288.PROD.OUTLOOK.COM (2603:10b6:c01:9e::21) To DS7PR12MB9473.namprd12.prod.outlook.com (2603:10b6:8:252::5) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS7PR12MB9473:EE_|CY5PR12MB6322:EE_ X-MS-Office365-Filtering-Correlation-Id: 4a4b89c7-dc14-4d35-3983-08deb41be7fc X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|366016|1800799024|11063799003|18002099003|22082099003|56012099003; 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The check is no longer needed. Signed-off-by: Zi Yan Reviewed-by: Lance Yang Reviewed-by: Lorenzo Stoakes (Oracle) Reviewed-by: Baolin Wang Acked-by: David Hildenbrand (Arm) Cc: Al Viro Cc: Barry Song Cc: Chris Mason Cc: Christian Brauner Cc: David Sterba Cc: Dev Jain Cc: Jan Kara Cc: Liam Howlett Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport Cc: Nico Pache Cc: Ryan Roberts Cc: Shuah Khan Cc: Song Liu Cc: Suren Baghdasaryan Cc: Vlastimil Babka --- mm/huge_memory.c | 30 +++--------------------------- 1 file changed, 3 insertions(+), 27 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index ed49e5d40e8f8..d055f53be8502 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3846,33 +3846,9 @@ int folio_check_splittable(struct folio *folio, unsigned int new_order, if (!folio->mapping && !folio_test_anon(folio)) return -EBUSY; - if (folio_test_anon(folio)) { - /* order-1 is not supported for anonymous THP. */ - if (new_order == 1) - return -EINVAL; - } else if (split_type == SPLIT_TYPE_NON_UNIFORM || new_order) { - if (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && - !mapping_large_folio_support(folio->mapping)) { - /* - * We can always split a folio down to a single page - * (new_order == 0) uniformly. - * - * For any other scenario - * a) uniform split targeting a large folio - * (new_order > 0) - * b) any non-uniform split - * we must confirm that the file system supports large - * folios. - * - * Note that we might still have THPs in such - * mappings, which is created from khugepaged when - * CONFIG_READ_ONLY_THP_FOR_FS is enabled. But in that - * case, the mapping does not actually support large - * folios properly. - */ - return -EINVAL; - } - } + /* order-1 is not supported for anonymous THP. */ + if (folio_test_anon(folio) && new_order == 1) + return -EINVAL; /* * swapcache folio could only be split to order 0 -- 2.53.0