fuse: move page alloc

fuse_req_pages_alloc() is moved to file.c, since its internal use by the
device code will eventually be removed.

Rename to fuse_pages_alloc() to signify that it's not only usable for
fuse_req page array.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

fs/fuse/dev.c

@@ -54,18 +54,6 @@ static void fuse_request_init(struct fuse_req *req, struct page **pages,
 	__set_bit(FR_PENDING, &req->flags);
 }
 
-static struct page **fuse_req_pages_alloc(unsigned int npages, gfp_t flags,
-					  struct fuse_page_desc **desc)
-{
-	struct page **pages;
-
-	pages = kzalloc(npages * (sizeof(struct page *) +
-				  sizeof(struct fuse_page_desc)), flags);
-	*desc = (void *) pages + npages * sizeof(struct page *);
-
-	return pages;
-}
-
 static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
 {
 	struct fuse_req *req = kmem_cache_zalloc(fuse_req_cachep, flags);
@@ -75,8 +63,7 @@ static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
 
 		WARN_ON(npages > FUSE_MAX_MAX_PAGES);
 		if (npages > FUSE_REQ_INLINE_PAGES) {
-			pages = fuse_req_pages_alloc(npages, flags,
-						     &page_descs);
+			pages = fuse_pages_alloc(npages, flags, &page_descs);
 			if (!pages) {
 				kmem_cache_free(fuse_req_cachep, req);
 				return NULL;
@@ -120,7 +107,7 @@ bool fuse_req_realloc_pages(struct fuse_conn *fc, struct fuse_req *req,
 				    fc->max_pages);
 	WARN_ON(npages <= req->max_pages);
 
-	pages = fuse_req_pages_alloc(npages, flags, &page_descs);
+	pages = fuse_pages_alloc(npages, flags, &page_descs);
 	if (!pages)
 		return false;
 

fs/fuse/file.c

@@ -19,6 +19,18 @@
 #include <linux/falloc.h>
 #include <linux/uio.h>
 
+struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
+			       struct fuse_page_desc **desc)
+{
+	struct page **pages;
+
+	pages = kzalloc(npages * (sizeof(struct page *) +
+				  sizeof(struct fuse_page_desc)), flags);
+	*desc = (void *) (pages + npages);
+
+	return pages;
+}
+
 static int fuse_send_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
 			  int opcode, struct fuse_open_out *outargp)
 {

fs/fuse/fuse_i.h

@@ -909,6 +909,8 @@ struct fuse_req *fuse_request_alloc(unsigned npages);
 
 struct fuse_req *fuse_request_alloc_nofs(unsigned npages);
 
+struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
+			       struct fuse_page_desc **desc);
 bool fuse_req_realloc_pages(struct fuse_conn *fc, struct fuse_req *req,
 			    gfp_t flags);