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See http://www.infradead.org/rpr.html X-Stat-Signature: y37ge6uih4nm8e43yi3ui4izgngiixkw X-Rspamd-Queue-Id: 81BD6100009 X-Rspamd-Server: rspam02 X-Rspam-User: X-HE-Tag: 1714112560-845742 X-HE-Meta: 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 jOmnwGb9 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 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: On Thu, Apr 25, 2024 at 01:37:42PM +0200, Pankaj Raghav (Samsung) wrote: > From: Pankaj Raghav > > iomap_dio_zero() will pad a fs block with zeroes if the direct IO size > < fs block size. iomap_dio_zero() has an implicit assumption that fs block > size < page_size. This is true for most filesystems at the moment. > > If the block size > page size, this will send the contents of the page > next to zero page(as len > PAGE_SIZE) to the underlying block device, > causing FS corruption. > > iomap is a generic infrastructure and it should not make any assumptions > about the fs block size and the page size of the system. So what happened to the plan to making huge_zero_page a folio and have it available for non-hugetlb setups? Not only would this be cleaner and more efficient, but it would actually work for the case where you'd have to zero more than 1MB on a 4k PAGE_SIZE system, which doesn't seem impossible with 2MB folios.