diff options
| author | David Howells <dhowells@redhat.com> | 2021-08-12 21:54:58 +0100 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2021-11-10 21:16:44 +0000 |
| commit | a19672f6b9718df247a9087a266150dbe833022e (patch) | |
| tree | 140dbfa75c026ddfa4e24d3fe897d34649dc31e7 /include/linux/pagemap.h | |
| parent | f89ce84bc33330607a782e47a8b19406ed109b15 (diff) | |
folio: Add a function to change the private data attached to a folio
Add a function, folio_change_private(), that will change the private data
attached to a folio, without the need to twiddle the private bit or the
refcount. It assumes that folio_add_private() has already been called on
the page.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Dominique Martinet <asmadeus@codewreck.org>
Tested-by: kafs-testing@auristor.com
Link: https://lore.kernel.org/r/162981149911.1901565.17776700811659843340.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163005743485.2472992.5100702469503007023.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163584180781.4023316.5037526301198034310.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/163649324326.309189.17817587229450840783.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/163657848531.834781.14269656212269187893.stgit@warthog.procyon.org.uk/ # v5
Diffstat (limited to 'include/linux/pagemap.h')
| -rw-r--r-- | include/linux/pagemap.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 6a30916b76e5..1f560aecd9b5 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -280,6 +280,25 @@ static inline void folio_attach_private(struct folio *folio, void *data) } /** + * folio_change_private - Change private data on a folio. + * @folio: Folio to change the data on. + * @data: Data to set on the folio. + * + * Change the private data attached to a folio and return the old + * data. The page must previously have had data attached and the data + * must be detached before the folio will be freed. + * + * Return: Data that was previously attached to the folio. + */ +static inline void *folio_change_private(struct folio *folio, void *data) +{ + void *old = folio_get_private(folio); + + folio->private = data; + return old; +} + +/** * folio_detach_private - Detach private data from a folio. * @folio: Folio to detach data from. * |