libceph: a few more osd data cleanups

These are very small changes that make use osd_data local pointers
as shorthands for structures being operated on.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

fs/ceph/addr.c

@@ -236,6 +236,7 @@ static int ceph_readpage(struct file *filp, struct page *page)
 static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
 {
 	struct inode *inode = req->r_inode;
+	struct ceph_osd_data *osd_data;
 	int rc = req->r_result;
 	int bytes = le32_to_cpu(msg->hdr.data_len);
 	int num_pages;
@@ -244,11 +245,12 @@ static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
 	dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes);
 
 	/* unlock all pages, zeroing any data we didn't read */
-	BUG_ON(req->r_data_in.type != CEPH_OSD_DATA_TYPE_PAGES);
-	num_pages = calc_pages_for((u64)req->r_data_in.alignment,
-					(u64)req->r_data_in.length);
+	osd_data = &req->r_data_in;
+	BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+	num_pages = calc_pages_for((u64)osd_data->alignment,
+					(u64)osd_data->length);
 	for (i = 0; i < num_pages; i++) {
-		struct page *page = req->r_data_in.pages[i];
+		struct page *page = osd_data->pages[i];
 
 		if (bytes < (int)PAGE_CACHE_SIZE) {
 			/* zero (remainder of) page */
@@ -263,7 +265,7 @@ static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
 		page_cache_release(page);
 		bytes -= PAGE_CACHE_SIZE;
 	}
-	kfree(req->r_data_in.pages);
+	kfree(osd_data->pages);
 }
 
 static void ceph_unlock_page_vector(struct page **pages, int num_pages)
@@ -557,6 +559,7 @@ static void writepages_finish(struct ceph_osd_request *req,
 {
 	struct inode *inode = req->r_inode;
 	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_osd_data *osd_data;
 	unsigned wrote;
 	struct page *page;
 	int num_pages;
@@ -569,9 +572,10 @@ static void writepages_finish(struct ceph_osd_request *req,
 	long writeback_stat;
 	unsigned issued = ceph_caps_issued(ci);
 
-	BUG_ON(req->r_data_out.type != CEPH_OSD_DATA_TYPE_PAGES);
-	num_pages = calc_pages_for((u64)req->r_data_out.alignment,
-					(u64)req->r_data_out.length);
+	osd_data = &req->r_data_out;
+	BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+	num_pages = calc_pages_for((u64)osd_data->alignment,
+					(u64)osd_data->length);
 	if (rc >= 0) {
 		/*
 		 * Assume we wrote the pages we originally sent.  The
@@ -589,7 +593,7 @@ static void writepages_finish(struct ceph_osd_request *req,
 
 	/* clean all pages */
 	for (i = 0; i < num_pages; i++) {
-		page = req->r_data_out.pages[i];
+		page = osd_data->pages[i];
 		BUG_ON(!page);
 		WARN_ON(!PageUptodate(page));
 
@@ -620,12 +624,12 @@ static void writepages_finish(struct ceph_osd_request *req,
 	dout("%p wrote+cleaned %d pages\n", inode, wrote);
 	ceph_put_wrbuffer_cap_refs(ci, num_pages, snapc);
 
-	ceph_release_pages(req->r_data_out.pages, num_pages);
-	if (req->r_data_out.pages_from_pool)
-		mempool_free(req->r_data_out.pages,
+	ceph_release_pages(osd_data->pages, num_pages);
+	if (osd_data->pages_from_pool)
+		mempool_free(osd_data->pages,
 			     ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool);
 	else
-		kfree(req->r_data_out.pages);
+		kfree(osd_data->pages);
 	ceph_osdc_put_request(req);
 }