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Wed, 10 Dec 2025 12:24:11 -0800 (PST) X-Google-Smtp-Source: AGHT+IEp/TCjQkjo9IXEU5scwVWKecCDQSTmMb8hfAZZ6nq5cmvChNS/S1r8YuGRQNN9gNusvbUp7Q== X-Received: by 2002:a05:6214:768:b0:880:501f:5e8 with SMTP id 6a1803df08f44-88863a2ab3amr50896356d6.13.1765398250715; Wed, 10 Dec 2025 12:24:10 -0800 (PST) Received: from x1.local ([142.188.210.156]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-8886ef0d241sm5052596d6.42.2025.12.10.12.24.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Dec 2025 12:24:10 -0800 (PST) Date: Wed, 10 Dec 2025 15:24:08 -0500 From: Peter Xu To: Matthew Wilcox Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jason Gunthorpe , Nico Pache , Zi Yan , Alex Mastro , David Hildenbrand , Alex Williamson , Zhi Wang , David Laight , Yi Liu , Ankit Agrawal , Kevin Tian , Andrew Morton , David Hildenbrand , Jonathan Corbet , linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, "Liam R. Howlett" , Lorenzo Stoakes , Vlastimil Babka , Jann Horn , Pedro Falcato , Alexander Viro , Christian Brauner , Jan Kara , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Subject: Re: [PATCH v2 2/4] mm: Add file_operations.get_mapping_order() Message-ID: References: <20251204151003.171039-1-peterx@redhat.com> <20251204151003.171039-3-peterx@redhat.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Mon, Dec 08, 2025 at 09:21:58AM +0000, Matthew Wilcox wrote: > On Thu, Dec 04, 2025 at 10:19:44AM -0500, Peter Xu wrote: > > > Add one new file operation, get_mapping_order(). It can be used by file > > > backends to report mapping order hints. > > This seems like a terrible idea. I'll look at it after Plumbers. Sure, no rush, please feel free to go through discussion in v1 when it comes, that's where we landed to this API based on suggestions from Jason. I'm open to other suggestions. -- Peter Xu