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Howlett" , Jens Axboe , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Simona Vetter , Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , Christian Schoenebeck , David Sterba , David Howells , Marc Dionne , Alexander Viro , Christian Brauner , Jan Kara , Benjamin LaHaise , Miklos Szeredi , Amir Goldstein , Kent Overstreet , "Tigran A . Aivazian" , Kees Cook , Chris Mason , Josef Bacik , Xiubo Li , Ilya Dryomov , Jan Harkes , coda@cs.cmu.edu, Tyler Hicks , Gao Xiang , Chao Yu , Yue Hu , Jeffle Xu , Sandeep Dhavale , Hongbo Li , Namjae Jeon , Sungjong Seo , Yuezhang Mo , Theodore Ts'o , Andreas Dilger , Jaegeuk Kim , OGAWA Hirofumi , Viacheslav Dubeyko , John Paul Adrian Glaubitz , Yangtao Li , Richard Weinberger , Anton Ivanov , Johannes Berg , Mikulas Patocka , David Woodhouse , Dave Kleikamp , Trond Myklebust , Anna Schumaker , Ryusuke Konishi , Konstantin Komarov , Mark Fasheh , Joel Becker , Joseph Qi , Bob Copeland , Mike Marshall , Martin Brandenburg , Steve French , Paulo Alcantara , Ronnie Sahlberg , Shyam Prasad N , Tom Talpey , Bharath SM , Zhihao Cheng , Hans de Goede , Carlos Maiolino , Damien Le Moal , Naohiro Aota , Johannes Thumshirn , Dan Williams , Matthew Wilcox , Vlastimil Babka , Jann Horn , Pedro Falcato , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, v9fs@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-afs@lists.infradead.org, linux-aio@kvack.org, linux-unionfs@vger.kernel.org, linux-bcachefs@vger.kernel.org, linux-mm@kvack.org, linux-btrfs@vger.kernel.org, ceph-devel@vger.kernel.org, codalist@coda.cs.cmu.edu, ecryptfs@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-um@lists.infradead.org, linux-mtd@lists.infradead.org, jfs-discussion@lists.sourceforge.net, linux-nfs@vger.kernel.org, linux-nilfs@vger.kernel.org, ntfs3@lists.linux.dev, ocfs2-devel@lists.linux.dev, linux-karma-devel@lists.sourceforge.net, devel@lists.orangefs.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-xfs@vger.kernel.org, nvdimm@lists.linux.dev Subject: Re: [PATCH 00/10] convert the majority of file systems to mmap_prepare Message-ID: <20250801140057.GA245321@nvidia.com> References: Content-Type: text/plain; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?hMUddmTaRFMyCibocSP07+b0aOshRc7yYilKjp3lsq0fykw1laPZVO6k8zQu?= =?us-ascii?Q?c6t/gQfz8hbRNl3OHgEVXTh32pju69RvBLfR/qMDE0DivO8pTX5X7M243szv?= =?us-ascii?Q?0NX2W5X/NLHxpjI+ZkGVzA7SZduy+etTGDP3xE6ua5wWeu+g77ZjhPeEzv26?= =?us-ascii?Q?kQFe4bE6+CvCoqJLQHD3oyJa8rehLE24QnSt7J0HBLMt5mPo1OBmjDDTCg0w?= =?us-ascii?Q?T6YdCT756jetHbwwgYLoXGSnhNFAzU2qm1984hD6V5QfrrcGslkzkJ3fMBeZ?= =?us-ascii?Q?xOcXsrU/nuTAaxFPNGBjdhf1WQudbMkcmPDaWC3ov5qyVs7Wjptm2ZYfmnuE?= =?us-ascii?Q?GKpX7oAgaYMuOFV06PtuEYAINGsHroz6JxdOIZazEJ3NkuCQ5HCbb6qGAc+7?= =?us-ascii?Q?/uf5h+9dQcQ9LgWmStq0ZOqSfbC66S7+g4kT4mB9to/7SbjNeJdyme1lvija?= =?us-ascii?Q?IgJkuqhN74NBWBtH2dCZjAyR+ibySxUqXSf7jjffduu6uC97QZMY79G0nLvJ?= =?us-ascii?Q?/9JSPvqALPQrTOQY280DSA4XlV7rdtyPZNba7C9QZdkESSeZG8Pja9id+7BA?= =?us-ascii?Q?Hcm/Dqv4LcQM9S6A0Wx2tmQquVq4RSHcdPWLG4g8SvHynI53t5DvhxDM1Dd7?= =?us-ascii?Q?ziMu1MlBcgHjR/ArqiZfEdJYKNZZQIHF/dNn+0HXTnIxzCv+lIGVFz+HEGGE?= =?us-ascii?Q?gE4MGIrWBgVCO9GnPbSKFgxoXYzFJXCWOEFTVdI9wsJWrUSL+55NZqOv8Yn9?= =?us-ascii?Q?Dyn9V3+KSehwlKmt81uRf8X8bl71FlFTrAjxHY8SlJlKU0q+as5O1+nXYCif?= =?us-ascii?Q?ur4XydwYsZKJERViPy/hFYmva9zEQKu+owU4iQdJFCP5Ahw9SkV755TRvqHL?= =?us-ascii?Q?tmPpgWqZ45OpKHKnBKvnu4/ekzZugcjBBGDG+FXdyMeYfq4ordTBRf4LyO2e?= =?us-ascii?Q?0VnHgbTldQC/kdsZPQqN87yWhVJW6Ei6i27GJpUEcWRYE0ljaD40ctSR9QBs?= =?us-ascii?Q?n9Xdz6+Vdxsu/2LAOmH6PdxKh2kqRLP3o1tsYrluCFbt9NA/SlFmx1BYissW?= =?us-ascii?Q?fXrpphbLTATE/uRP09J7KXaBe6pH4ufBCY+nfLAoQGgpDXBG2hlxggI6yNZp?= =?us-ascii?Q?Moq/vpGehxuvG+z0XG/PjSgLuxkEXBiOIZwmwxVXqsajiqOuLqdmnsb+exlT?= =?us-ascii?Q?PmaQAv29yNUwOEnZlED2TnXqfcx0vFFCdLa027ivFdhSE1eIkpuLhmOs9CXC?= =?us-ascii?Q?TjjNWyCrqdiHR8/T1acCOyVxTpbLy4vwb4f56AGhSm6m+2KS9lACn39Uimyr?= =?us-ascii?Q?yP1MTkLn++HgbpLiGTKEXUi51EJlBawoxDu7teFGwVfNLFHe0bT4JWFrZJNl?= =?us-ascii?Q?tjz8Jz8dq/c04L7OxdP861fohdGcGPbgtZBU482FGgLgNP4lBc8B5T6QBt8H?= =?us-ascii?Q?EOov+HdqOKkWJlRMoqygvOsVRT0bEqDREWvDW/h1MigOEOsYvdZiT5vgpn5N?= =?us-ascii?Q?VIkDg9ZL8vHugqvs+2TLSY55LkvuTz7VPC56Dz9VRoXMKTX4nH4mFWESQ/Av?= =?us-ascii?Q?bPYSEl/ftfkJeJxkVwM=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0a3ddb5a-3da4-46ed-7081-08ddd103d741 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Aug 2025 14:00:58.5324 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: v98ANgD/PTWLentAZ3Ru4Pk6xjLTn0ZKxMq/ka65h6zomjl8gbh+qcAlIi24SW3A X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW3PR12MB4428 On Mon, Jun 16, 2025 at 08:33:19PM +0100, Lorenzo Stoakes wrote: > The intent is to gradually deprecate f_op->mmap, and in that vein this > series coverts the majority of file systems to using f_op->mmap_prepare. I saw this on lwn and just wanted to give a little bit of thought on this topic.. It looks to me like we need some more infrastructure to convert anything that uses remap_pfn/etc in the mmap() callback I would like to suggest we add a vma->prepopulate() callback which is where the remap_pfn should go. Once the VMA is finalized and fully operational the vma_ops have the opportunity to prepopulate any PTEs. This could then actually be locked properly so it is safe with concurrent unmap_mapping_range() (current mmap callback is not safe) Jason