libceph, ceph: change ceph_calc_file_object_mapping() signature

- make it void
- xlen (object extent length) out parameter should be u32 because only
  a single stripe unit is mapped at a time
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>

fs/ceph/addr.c

@@ -945,19 +945,15 @@ static int ceph_writepages_start(struct address_space *mapping,
 			if (locked_pages == 0) {
 				u64 objnum;
 				u64 objoff;
+				u32 xlen;
 
 				/* prepare async write request */
 				offset = (u64)page_offset(page);
-				len = wsize;
-
-				rc = ceph_calc_file_object_mapping(&ci->i_layout,
-								offset, len,
-								&objnum, &objoff,
-								&len);
-				if (rc < 0) {
-					unlock_page(page);
-					break;
-				}
+				ceph_calc_file_object_mapping(&ci->i_layout,
+							      offset, wsize,
+							      &objnum, &objoff,
+							      &xlen);
+				len = xlen;
 
 				num_ops = 1;
 				strip_unit_end = page->index +

fs/ceph/ioctl.c

@@ -185,7 +185,7 @@ static long ceph_ioctl_get_dataloc(struct file *file, void __user *arg)
 		&ceph_sb_to_client(inode->i_sb)->client->osdc;
 	struct ceph_object_locator oloc;
 	CEPH_DEFINE_OID_ONSTACK(oid);
-	u64 len = 1, olen;
+	u32 xlen;
 	u64 tmp;
 	struct ceph_pg pgid;
 	int r;
@@ -195,13 +195,8 @@ static long ceph_ioctl_get_dataloc(struct file *file, void __user *arg)
 		return -EFAULT;
 
 	down_read(&osdc->lock);
-	r = ceph_calc_file_object_mapping(&ci->i_layout, dl.file_offset, len,
-					  &dl.object_no, &dl.object_offset,
-					  &olen);
-	if (r < 0) {
-		up_read(&osdc->lock);
-		return -EIO;
-	}
+	ceph_calc_file_object_mapping(&ci->i_layout, dl.file_offset, 1,
+				      &dl.object_no, &dl.object_offset, &xlen);
 	dl.file_offset -= dl.object_offset;
 	dl.object_size = ci->i_layout.object_size;
 	dl.block_size = ci->i_layout.stripe_unit;

include/linux/ceph/osdmap.h

@@ -280,10 +280,9 @@ bool ceph_osds_changed(const struct ceph_osds *old_acting,
 		       const struct ceph_osds *new_acting,
 		       bool any_change);
 
-/* calculate mapping of a file extent to an object */
-extern int ceph_calc_file_object_mapping(struct ceph_file_layout *layout,
-					 u64 off, u64 len,
-					 u64 *bno, u64 *oxoff, u64 *oxlen);
+void ceph_calc_file_object_mapping(struct ceph_file_layout *l,
+				   u64 off, u64 len,
+				   u64 *objno, u64 *objoff, u32 *xlen);
 
 int __ceph_object_locator_to_pg(struct ceph_pg_pool_info *pi,
 				const struct ceph_object_id *oid,

net/ceph/osd_client.c

@@ -103,13 +103,12 @@ static int calc_layout(struct ceph_file_layout *layout, u64 off, u64 *plen,
 			u64 *objnum, u64 *objoff, u64 *objlen)
 {
 	u64 orig_len = *plen;
-	int r;
+	u32 xlen;
 
 	/* object extent? */
-	r = ceph_calc_file_object_mapping(layout, off, orig_len, objnum,
-					  objoff, objlen);
-	if (r < 0)
-		return r;
+	ceph_calc_file_object_mapping(layout, off, orig_len, objnum,
+					  objoff, &xlen);
+	*objlen = xlen;
 	if (*objlen < orig_len) {
 		*plen = *objlen;
 		dout(" skipping last %llu, final file extent %llu~%llu\n",
@@ -117,7 +116,6 @@ static int calc_layout(struct ceph_file_layout *layout, u64 off, u64 *plen,
 	}
 
 	dout("calc_layout objnum=%llx %llu~%llu\n", *objnum, *objoff, *objlen);
-
 	return 0;
 }
 

net/ceph/osdmap.c

@@ -2153,9 +2153,9 @@ bool ceph_osds_changed(const struct ceph_osds *old_acting,
  * objno     |      0      |      1      |      2      |      3      |      4
  * objsetno  |                    0                    |                    1
  */
-int ceph_calc_file_object_mapping(struct ceph_file_layout *l,
+void ceph_calc_file_object_mapping(struct ceph_file_layout *l,
 				   u64 off, u64 len,
-				   u64 *objno, u64 *objoff, u64 *xlen)
+				   u64 *objno, u64 *objoff, u32 *xlen)
 {
 	u32 stripes_per_object = l->object_size / l->stripe_unit;
 	u64 blockno;	/* which su in the file (i.e. globally) */
@@ -2173,8 +2173,6 @@ int ceph_calc_file_object_mapping(struct ceph_file_layout *l,
 	*objno = objsetno * l->stripe_count + stripepos;
 	*objoff = objsetpos * l->stripe_unit + blockoff;
 	*xlen = min_t(u64, len, l->stripe_unit - blockoff);
-
-	return 0;
 }
 EXPORT_SYMBOL(ceph_calc_file_object_mapping);