udf: Provide function for calculating dir entry length

Provide function for calculating directory entry length and use to
reduce code duplication.
Signed-off-by: Jan Kara <jack@suse.cz>

fs/udf/directory.c

@@ -141,10 +141,7 @@ struct fileIdentDesc *udf_fileident_read(struct inode *dir, loff_t *nf_pos,
 			       fibh->ebh->b_data,
 			       sizeof(struct fileIdentDesc) + fibh->soffset);
 
-			fi_len = (sizeof(struct fileIdentDesc) +
-				  cfi->lengthFileIdent +
-				  le16_to_cpu(cfi->lengthOfImpUse) + 3) & ~3;
-
+			fi_len = udf_dir_entry_len(cfi);
 			*nf_pos += fi_len - (fibh->eoffset - fibh->soffset);
 			fibh->eoffset = fibh->soffset + fi_len;
 		} else {

fs/udf/namei.c

@@ -351,8 +351,6 @@ static struct fileIdentDesc *udf_add_entry(struct inode *dir,
 	loff_t f_pos;
 	loff_t size = udf_ext0_offset(dir) + dir->i_size;
 	int nfidlen;
-	uint8_t lfi;
-	uint16_t liu;
 	udf_pblk_t block;
 	struct kernel_lb_addr eloc;
 	uint32_t elen = 0;
@@ -383,7 +381,7 @@ static struct fileIdentDesc *udf_add_entry(struct inode *dir,
 		namelen = 0;
 	}
 
-	nfidlen = (sizeof(struct fileIdentDesc) + namelen + 3) & ~3;
+	nfidlen = ALIGN(sizeof(struct fileIdentDesc) + namelen, UDF_NAME_PAD);
 
 	f_pos = udf_ext0_offset(dir);
 
@@ -424,12 +422,8 @@ static struct fileIdentDesc *udf_add_entry(struct inode *dir,
 			goto out_err;
 		}
 
-		liu = le16_to_cpu(cfi->lengthOfImpUse);
-		lfi = cfi->lengthFileIdent;
-
 		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
-			if (((sizeof(struct fileIdentDesc) +
-					liu + lfi + 3) & ~3) == nfidlen) {
+			if (udf_dir_entry_len(cfi) == nfidlen) {
 				cfi->descTag.tagSerialNum = cpu_to_le16(1);
 				cfi->fileVersionNum = cpu_to_le16(1);
 				cfi->fileCharacteristics = 0;
@@ -1201,9 +1195,7 @@ static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
 
 	if (dir_fi) {
 		dir_fi->icb.extLocation = cpu_to_lelb(UDF_I(new_dir)->i_location);
-		udf_update_tag((char *)dir_fi,
-				(sizeof(struct fileIdentDesc) +
-				le16_to_cpu(dir_fi->lengthOfImpUse) + 3) & ~3);
+		udf_update_tag((char *)dir_fi, udf_dir_entry_len(dir_fi));
 		if (old_iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
 			mark_inode_dirty(old_inode);
 		else

fs/udf/udfdecl.h

@@ -132,6 +132,12 @@ struct inode *udf_find_metadata_inode_efe(struct super_block *sb,
 extern int udf_write_fi(struct inode *inode, struct fileIdentDesc *,
 			struct fileIdentDesc *, struct udf_fileident_bh *,
 			uint8_t *, uint8_t *);
+static inline unsigned int udf_dir_entry_len(struct fileIdentDesc *cfi)
+{
+	return ALIGN(sizeof(struct fileIdentDesc) +
+		le16_to_cpu(cfi->lengthOfImpUse) + cfi->lengthFileIdent,
+		UDF_NAME_PAD);
+}
 
 /* file.c */
 extern long udf_ioctl(struct file *, unsigned int, unsigned long);