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Howlett" , Matthew Wilcox , Mike Kravetz , Mike Rapoport , Muchun Song , Nadav Amit , Peter Xu , Shuah Khan , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 8950540029 X-Stat-Signature: oya54skhmgkr3bs4ypopqmt55ztstcrp X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1677173523-398561 X-HE-Meta: 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 Fjc1yTI1 NthLN5RTj1GxsvD/zjSMfXlKldb3kbrWEiNMdUP/BOrhY2LYVyeRzz1I7X7KNvEmhIajY+/PYLAsSDcIWoFHdKV6MTx1hn9mjCvoFmdrUq5sQKxO+w/jGy6I88eSDK4ifPEnabuTl+OUXYbxt+AXUym92cN4mQMmWuiN67S3ZFhLQK41xe1rnqTiKN1mRShwAGcluC16VxkWRQEnsIIr7KKOE+hxzApC+01fHs/K9b8m0H3AGd2dBTHvV0dOWi5Dq6s3fYvW+vEqhKCcGV/KOVnornTViwY4iWkVZ+rTO1723Ljq0BuMpo09Ac423m3SFlSFGRHduBQCFUkpqqn70UeCvlit63i25HTmX 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: On Wed, Feb 22, 2023 at 4:58 PM Axel Rasmussen wrote: > > Many userfaultfd ioctl functions take both a 'mode' and a 'wp_copy' > argument. In future commits we plan to plumb the flags through to more > places, so we'd be proliferating the very long argument list even > further. > > Let's take the time to simplify the argument list. Combine the two > arguments into one - and generalize, so when we add more flags in the > future, it doesn't imply more function arguments. > > Since the modes (copy, zeropage, continue) are mutually exclusive, store > them as an integer value (0, 1, 2) in the low bits. Place combine-able > flag bits in the high bits. > > Signed-off-by: Axel Rasmussen Acked-by: James Houghton I don't see anything wrong with this patch. Thanks, Axel.