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charset=us-ascii Content-Disposition: inline In-Reply-To: <80D4F8CE-FCFF-44F9-8846-6098FAC76082@nvidia.com> X-Rspamd-Queue-Id: A532210000F X-Stat-Signature: 8wszeuntzrn1hxwnnfz4up9ppkd5f63i X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1759144139-422705 X-HE-Meta: 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 bo4/UPkn YIESX1mj3doVxXPbzhseH+bzQyVOjUuhj3cjU3XUdONyfVKgsEeWm9u5OIVigtPFEHrSgoOSGszMt/8aAxSxpZB5loNQFsTD2uBOqjEiNOI8riALa6AvuH4JGX9p05elaaqrnI7ujuAEnfia3lND0uRwXkuThgsX3wiPsv7iFR2EYUl2hmMlzeEtFCOKpBMgkyJd1m8DPP/t35amV4CgRHZtM1qHwWQCxTyvwDJ+UHhtRAaFGB1z61yEvPM1ltj9C84UiEiHlX43S63oDhRtx/nRwXWE/sF4LVFMieSZzcB8ujqaWksQjhArPY5KDP0Bp2VVd1gUQocMB3cqkUD1U559w3L8s4ef9tEl/jLBaiSShR5qyUmnRuqx2FGwpOEqDlW5rEWzlaRctx9/PnTCsZpgEMAItQQK6YgaCSWzaXWep7nhHKUune95IPepefw48RuFTSnIjeHDaBlPopmigq45rYnBXVOqTcL8KCDc6JGfKZ4Q= 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: > > I want to change all the split functions in huge_mm.h and provide > mapping_min_folio_order() to try_folio_split() in truncate_inode_partial_folio(). > > Something like below: > > 1. no split function will change the given order; > 2. __folio_split() will no longer give VM_WARN_ONCE when provided new_order > is smaller than mapping_min_folio_order(). > > In this way, for an LBS folio that cannot be split to order 0, split > functions will return -EINVAL to tell caller that the folio cannot > be split. The caller is supposed to handle the split failure. IIUC, we will remove warn on once but just return -EINVAL in __folio_split() function if new_order < min_order like this: ... min_order = mapping_min_folio_order(folio->mapping); if (new_order < min_order) { - VM_WARN_ONCE(1, "Cannot split mapped folio below min-order: %u", - min_order); ret = -EINVAL; goto out; } ... > > WDYT? > I think it should be fine as along as we return an error if someone is trying to split < min_order for file-backed folios. > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h > index f327d62fc985..e15c3ca07e33 100644 > --- a/include/linux/huge_mm.h > +++ b/include/linux/huge_mm.h > @@ -387,34 +387,16 @@ int folio_split(struct folio *folio, unsigned int new_order, struct page *page, > * Return: 0: split is successful, otherwise split failed. > */ > static inline int try_folio_split(struct folio *folio, struct page *page, > - struct list_head *list) > + struct list_head *list, unsigned int order) > { -- Pankaj