erofs: some macros are much more readable as a function

As Christoph suggested [1], these macros are much
more readable as a function.

[1] https://lore.kernel.org/r/20190829095954.GB20598@infradead.org/Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190904020912.63925-4-gaoxiang25@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/erofs/erofs_fs.h

@@ -171,16 +171,22 @@ struct erofs_xattr_entry {
 	char   e_name[0];       /* attribute name */
 } __packed;
 
-#define ondisk_xattr_ibody_size(count)	({\
-	u32 __count = le16_to_cpu(count); \
-	((__count) == 0) ? 0 : \
-	sizeof(struct erofs_xattr_ibody_header) + \
-		sizeof(__u32) * ((__count) - 1); })
+static inline unsigned int erofs_xattr_ibody_size(__le16 i_xattr_icount)
+{
+	if (!i_xattr_icount)
+		return 0;
+
+	return sizeof(struct erofs_xattr_ibody_header) +
+		sizeof(__u32) * (le16_to_cpu(i_xattr_icount) - 1);
+}
 
 #define EROFS_XATTR_ALIGN(size) round_up(size, sizeof(struct erofs_xattr_entry))
-#define EROFS_XATTR_ENTRY_SIZE(entry) EROFS_XATTR_ALIGN( \
-	sizeof(struct erofs_xattr_entry) + \
-	(entry)->e_name_len + le16_to_cpu((entry)->e_value_size))
+
+static inline unsigned int erofs_xattr_entry_size(struct erofs_xattr_entry *e)
+{
+	return EROFS_XATTR_ALIGN(sizeof(struct erofs_xattr_entry) +
+				 e->e_name_len + le16_to_cpu(e->e_value_size));
+}
 
 /* available compression algorithm types */
 enum {

fs/erofs/inode.c

@@ -29,7 +29,7 @@ static int read_inode(struct inode *inode, void *data)
 		struct erofs_inode_v2 *v2 = data;
 
 		vi->inode_isize = sizeof(struct erofs_inode_v2);
-		vi->xattr_isize = ondisk_xattr_ibody_size(v2->i_xattr_icount);
+		vi->xattr_isize = erofs_xattr_ibody_size(v2->i_xattr_icount);
 
 		inode->i_mode = le16_to_cpu(v2->i_mode);
 		if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
@@ -62,7 +62,7 @@ static int read_inode(struct inode *inode, void *data)
 		struct erofs_sb_info *sbi = EROFS_SB(inode->i_sb);
 
 		vi->inode_isize = sizeof(struct erofs_inode_v1);
-		vi->xattr_isize = ondisk_xattr_ibody_size(v1->i_xattr_icount);
+		vi->xattr_isize = erofs_xattr_ibody_size(v1->i_xattr_icount);
 
 		inode->i_mode = le16_to_cpu(v1->i_mode);
 		if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||

fs/erofs/xattr.c

@@ -231,7 +231,7 @@ static int xattr_foreach(struct xattr_iter *it,
 	 */
 	entry = *(struct erofs_xattr_entry *)(it->kaddr + it->ofs);
 	if (tlimit) {
-		unsigned int entry_sz = EROFS_XATTR_ENTRY_SIZE(&entry);
+		unsigned int entry_sz = erofs_xattr_entry_size(&entry);
 
 		/* xattr on-disk corruption: xattr entry beyond xattr_isize */
 		if (*tlimit < entry_sz) {