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charset="UTF-8" X-Rspamd-Queue-Id: B618A1C0006 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: 4cpj1oumqtqn3tggni955sgxyw7etam5 X-HE-Tag: 1674045566-87955 X-HE-Meta: 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 5U+8uXkc LvTbW/yN934LveUMz67x1Sz0gtwCOTOHcz+DkFxknpJfiXtq1KJh0aVcCBWl1TimhhLlfqyZOLXLLdbOOabUB96Wx1yKamgPc2uarzcqx3wSXVVCivWOZP+Skqi0hr4TdMIox 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, Jan 18, 2023 at 7:41 PM Christoph Hellwig wrote: > > Instead of returning NULL for all errors, distinguish between: > > - no entry found and not asked to allocated (-ENOENT) > - failed to allocate memory (-ENOMEM) > - would block (-EAGAIN) > > so that callers don't have to guess the error based on the passed > in flags. > > Also pass through the error through the direct callers: > filemap_get_folio, filemap_lock_folio filemap_grab_folio > and filemap_get_incore_folio. As for the comments describing the return values of these callers, isn't it necessary to rewrite the value from NULL in case of errors ? Regards, Ryusuke Konishi