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De Francesco" , Jonathan Corbet , Andrew Morton , "Mike Rapoport (IBM)" , Deming Wang , Ira Weiny , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Catalin Marinas , Mike Rapoport , Peter Collingbourne , Peter Zijlstra , Sebastian Andrzej Siewior , Thomas Gleixner , Vlastimil Babka , Will Deacon References: <20230701142041.9992-1-fmdefrancesco@gmail.com> <68a9b3aa-d064-ed6a-2bcd-9423eb4f595c@infradead.org> From: Randy Dunlap In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 3CE831C0004 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: ioatu1hreiijupwjdtu5mj8mcyrngrnp X-HE-Tag: 1688255961-196092 X-HE-Meta: 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 2SUajtI5 GYl3szJKlX1aeoMEAByFRfLOlAxm2dPNzpuzvPy14lqUoaIOypnzsgizhYLhdIWf11BgqaeWbXW+Iy+UaS3R7NSLDj5fOOje99nZFT9qUzF8LLQOT3frH8vlZtzcSz2/avQEntrrcU6jP8BW4ywNZTfLLHhb1LTqmi4OMRmdNxeWVkGcQ03/Q8ZtGGc3zlzMf6JAufkkQwRCekV8sRoDH1DbSk1P7lhiVL6RPolvMwzWYJNMolrvPkZz7zA== 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 7/1/23 16:54, Matthew Wilcox wrote: > On Sat, Jul 01, 2023 at 08:21:20AM -0700, Randy Dunlap wrote: >>> -* kmap_local_page(). This function is used to require short term mappings. >>> - It can be invoked from any context (including interrupts) but the mappings >>> - can only be used in the context which acquired them. >>> - >>> - This function should always be used, whereas kmap_atomic() and kmap() have >>> +* kmap_local_page(), kmap_local_folio() - These functions are used to require >> >> acquire ? > > "create" might be better? Yes, that's good. >>> + short term mappings. They can be invoked from any context (including >>> + interrupts) but the mappings can only be used in the context which acquired >>> + them. The only differences between them consist in the first taking a pointer >>> + to a struct page and the second taking a pointer to struct folio and the byte >>> + offset within the folio which identifies the page. >> >> -- >> ~Randy -- ~Randy