cifs: read pages from FS-Cache

Read pages from a FS-Cache data storage object into a CIFS inode.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 39 insertions, 1 deletions

diff --git a/fs/cifs/fscache.h b/fs/cifs/fscache.h
index 1a00d70bca9..79164c66797 100644
--- a/fs/cifs/fscache.h
+++ b/fs/cifs/fscache.h
@@ -32,7 +32,6 @@ extern const struct fscache_cookie_def cifs_fscache_server_index_def;
 extern const struct fscache_cookie_def cifs_fscache_super_index_def;
 extern const struct fscache_cookie_def cifs_fscache_inode_object_def;
 
-
 extern int cifs_fscache_register(void);
 extern void cifs_fscache_unregister(void);
 
@@ -50,6 +49,11 @@ extern void cifs_fscache_reset_inode_cookie(struct inode *);
 
 extern void __cifs_fscache_invalidate_page(struct page *, struct inode *);
 extern int cifs_fscache_release_page(struct page *page, gfp_t gfp);
+extern int __cifs_readpage_from_fscache(struct inode *, struct page *);
+extern int __cifs_readpages_from_fscache(struct inode *,
+					 struct address_space *,
+					 struct list_head *,
+					 unsigned *);
 
 extern void __cifs_readpage_to_fscache(struct inode *, struct page *);
 
@@ -60,6 +64,26 @@ static inline void cifs_fscache_invalidate_page(struct page *page,
 		__cifs_fscache_invalidate_page(page, inode);
 }
 
+static inline int cifs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
+{
+	if (CIFS_I(inode)->fscache)
+		return __cifs_readpage_from_fscache(inode, page);
+
+	return -ENOBUFS;
+}
+
+static inline int cifs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	if (CIFS_I(inode)->fscache)
+		return __cifs_readpages_from_fscache(inode, mapping, pages,
+						     nr_pages);
+	return -ENOBUFS;
+}
+
 static inline void cifs_readpage_to_fscache(struct inode *inode,
 					    struct page *page)
 {
@@ -90,6 +114,20 @@ static inline void cifs_fscache_release_page(struct page *page, gfp_t gfp)
 
 static inline int cifs_fscache_invalidate_page(struct page *page,
 			struct inode *) {}
+static inline int
+cifs_readpage_from_fscache(struct inode *inode, struct page *page)
+{
+	return -ENOBUFS;
+}
+
+static inline int cifs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	return -ENOBUFS;
+}
+
 static inline void cifs_readpage_to_fscache(struct inode *inode,
 			struct page *page) {}