extern void __fscache_uncache_page(struct fscache_cookie *, struct page *);
extern bool __fscache_check_page_write(struct fscache_cookie *, struct page *);
extern void __fscache_wait_on_page_write(struct fscache_cookie *, struct page *);
+extern bool __fscache_maybe_release_page(struct fscache_cookie *, struct page *,
+ gfp_t);
/**
* fscache_register_netfs - Register a filesystem as desiring caching services
__fscache_wait_on_page_write(cookie, page);
}
+/**
+ * fscache_maybe_release_page - Consider releasing a page, cancelling a store
+ * @cookie: The cookie representing the cache object
+ * @page: The netfs page that is being cached.
+ * @gfp: The gfp flags passed to releasepage()
+ *
+ * Consider releasing a page for the vmscan algorithm, on behalf of the netfs's
+ * releasepage() call. A storage request on the page may cancelled if it is
+ * not currently being processed.
+ *
+ * The function returns true if the page no longer has a storage request on it,
+ * and false if a storage request is left in place. If true is returned, the
+ * page will have been passed to fscache_uncache_page(). If false is returned
+ * the page cannot be freed yet.
+ */
+static inline
+bool fscache_maybe_release_page(struct fscache_cookie *cookie,
+ struct page *page,
+ gfp_t gfp)
+{
+ if (fscache_cookie_valid(cookie) && PageFsCache(page))
+ return __fscache_maybe_release_page(cookie, page, gfp);
+ return false;
+}
+
#endif /* _LINUX_FSCACHE_H */