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linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, fuse-devel@lists.linux.dev Subject: Re: [PATCH v3 09/40] docs: filesystems: update mmap_prepare docs for discontig kernel pgs Message-ID: References: <20260917-b4-mmap-prepare-vma-flag-sanify-v3-0-4583d8a23bca@kernel.org> <20260917-b4-mmap-prepare-vma-flag-sanify-v3-9-4583d8a23bca@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: D0F544000F X-Rspam-User: X-Rspamd-Server: rspam07 X-Stat-Signature: 3tnde4b4smt5uprfg3rz4wb7b5umipy8 X-HE-Tag: 1790680918-927616 X-HE-Meta: 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OUyjFityG5LzmCrQ8887eJb5VUCM+Th12GPRbggSLRVSiKW2u3CKM2uUG0VfYzw1wAUA7TSbrf4BnF3aY2rjXnaaQRrbw5OIfkXTl3IoX+Xxs0CIGdviTX7mzLbPqWggLHqoc+C/Iq7UIq9c0E94YWvZmRFcb3ScNkGxTNUqPyOneFcYfFplrS+abSSrqSumLEBCt1ElTe1DF1S2/izaUSzETss1cVPQxMpV+gC2VpcbFlrI/z/sPEekhR43ysqgn2Q4B4Zht32D4PhwYAy7FqrTBlQdVULS1mS5J2mLB1hGruxOuMthN1El2J1eRusR8d6Jjg3l+9+99Z3Umb/lR8 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Sep 25, 2026 at 05:01:51PM -0400, Zi Yan wrote: > On Thu Sep 17, 2026 at 12:22 PM EDT, Lorenzo Stoakes (ARM) wrote: > > Documentation/filesystems/mmap_prepare.rst | 81 ++++++++++++++++++++++++++++++ > > +* ``discontig_kernel_map_page()`` - Maps a single page, correctly handling > > + compound pages (if the compound page is bigger than the remaining pages in the > > + VMA, then only those pages that fit will be mapped). For a compound page, the > > + head page must be passed. > > +* ``discontig_kernel_map_page_range()`` - Map an array of pages of a specified > > + size. Note that if the number of pages specified exceeds the VMA size then an > > + error will arise. > > Why do mapping a compound page and a page range have different behaviors > on the bound? Either both do partial mappings or give errors when a > given input cannot be mapped as a whole in the VMA. Ack, yeah similar to Suren's point on patch 8, will clamp for both. -- Cheers, Lorenzo