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Miller" , Andreas Larsson , Arnd Bergmann , Greg Kroah-Hartman , Dan Williams , Vishal Verma , Dave Jiang , Nicolas Pitre , Muchun Song , Oscar Salvador , David Hildenbrand , Konstantin Komarov , Baoquan He , Vivek Goyal , Dave Young , Tony Luck , Reinette Chatre , Dave Martin , James Morse , Alexander Viro , Christian Brauner , Jan Kara , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Hugh Dickins , Baolin Wang , Uladzislau Rezki , Dmitry Vyukov , Andrey Konovalov , Jann Horn , Pedro Falcato , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-csky@vger.kernel.org, linux-mips@vger.kernel.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, linux-mm@kvack.org, ntfs3@lists.linux.dev, kexec@lists.infradead.org, kasan-dev@googlegroups.com, Jason Gunthorpe References: <1ceb56fec97f891df5070b24344bf2009aca6655.1757329751.git.lorenzo.stoakes@oracle.com> Content-Language: en-US From: Randy Dunlap In-Reply-To: <1ceb56fec97f891df5070b24344bf2009aca6655.1757329751.git.lorenzo.stoakes@oracle.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 49F4480003 X-Stat-Signature: 33dkydx6eogg157tidbf4b43se8sbjee X-HE-Tag: 1757373464-943304 X-HE-Meta: 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 P+LXTJlS Id8kBfy2UjzSYfIkR7bx69LaTNPWRGSBIC4u9e7NvTfLw9TizrhxM3zukILvAmONuTwtFNLIOw4KQTNsDi/rDB5lIs9u8XK80dimLTrilFJVelUD0nOTp/y3KhXYaL0SLLR50XkcaRlP7RLBZ+RkStblHIemBiDb4vKozDrhRLDcNOH0G5lELA2uzjFPrMCv+jtoTOJqjbePpFg2HdCknTaoIRCxJdATEHW7h68+GVpRuuUOVysJyxZtKxXKrgE9oBL4i+VCJXm1NETq2qfzB7/DeBlcRkpJ5hXe2uDlm0VmA0Z9ie2VLMUd9AA5/wA1V6OxvonKt9Hgz8LE= 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: Hi-- On 9/8/25 4:10 AM, Lorenzo Stoakes wrote: > We have introduced the mmap_complete() and mmap_abort() callbacks, which > work in conjunction with mmap_prepare(), so describe what they used for. > > We update both the VFS documentation and the porting guide. > > Signed-off-by: Lorenzo Stoakes > --- > Documentation/filesystems/porting.rst | 9 +++++++ > Documentation/filesystems/vfs.rst | 35 +++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+) > > diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst > index 486a91633474..172d36a13e13 100644 > --- a/Documentation/filesystems/vfs.rst > +++ b/Documentation/filesystems/vfs.rst > @@ -1236,6 +1240,37 @@ otherwise noted. > file-backed memory mapping, most notably establishing relevant > private state and VMA callbacks. > > +``mmap_complete`` > + If mmap_prepare is provided, will be invoked after the mapping is fully s/mmap_prepare/mmap_complete/ ?? > + established, with the mmap and VMA write locks held. > + > + It is useful for prepopulating VMAs before they may be accessed by > + users. > + > + The hook MUST NOT release either the VMA or mmap write locks. This is You could also do **bold** above: The hook **MUST NOT** release ... > + asserted by the mmap logic. > + > + If an error is returned by the hook, the VMA is unmapped and the > + mmap() operation fails with that error. > + > + It is not valid to specify this hook if mmap_prepare is not also > + specified, doing so will result in an error upon mapping. -- ~Randy