ceph: kill ceph_osdc_writepages() "nofail" parameter

There is only one caller of ceph_osdc_writepages(), and it always
passes the value true as its "nofail" argument.  Get rid of that
argument and replace its use in ceph_osdc_writepages() with the
constant value true.

This and a number of cleanup patches that follow resolve:
    http://tracker.ceph.com/issues/4126

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

fs/ceph/addr.c

@@ -493,7 +493,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 				   page_off, len,
 				   ci->i_truncate_seq, ci->i_truncate_size,
 				   &inode->i_mtime,
-				   &page, 1, 0, 0, true);
+				   &page, 1, 0, 0);
 	if (err < 0) {
 		dout("writepage setting page/mapping error %d %p\n", err, page);
 		SetPageError(page);

include/linux/ceph/osd_client.h

@@ -275,7 +275,7 @@ extern int ceph_osdc_writepages(struct ceph_osd_client *osdc,
 				u32 truncate_seq, u64 truncate_size,
 				struct timespec *mtime,
 				struct page **pages, int nr_pages,
-				int flags, int do_sync, bool nofail);
+				int flags, int do_sync);
 
 /* watch/notify events */
 extern int ceph_osdc_create_event(struct ceph_osd_client *osdc,

net/ceph/osd_client.c

@@ -1867,7 +1867,7 @@ int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
 			 u32 truncate_seq, u64 truncate_size,
 			 struct timespec *mtime,
 			 struct page **pages, int num_pages,
-			 int flags, int do_sync, bool nofail)
+			 int flags, int do_sync)
 {
 	struct ceph_osd_request *req;
 	int rc = 0;
@@ -1880,7 +1880,7 @@ int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
 					    CEPH_OSD_FLAG_WRITE,
 				    snapc, do_sync,
 				    truncate_seq, truncate_size, mtime,
-				    nofail, 1, page_align);
+				    true, 1, page_align);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
@@ -1889,7 +1889,7 @@ int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
 	dout("writepages %llu~%llu (%d pages)\n", off, len,
 	     req->r_num_pages);
 
-	rc = ceph_osdc_start_request(osdc, req, nofail);
+	rc = ceph_osdc_start_request(osdc, req, true);
 	if (!rc)
 		rc = ceph_osdc_wait_request(osdc, req);