[PATCH v4 2/7] erofs: some macros are much more readable as a function

Gao Xiang gaoxiang25 at huawei.com
Fri Aug 30 13:38:32 AEST 2019


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 at infradead.org>
Signed-off-by: Gao Xiang <gaoxiang25 at huawei.com>
---
v4: a type fix in commit message.
v3: change as Joe suggested,
 https://lore.kernel.org/r/5b2ecf5cec1a6aa3834e9af41886a7fcb18ae86a.camel@perches.com/

 fs/erofs/erofs_fs.h | 24 ++++++++++++++++--------
 fs/erofs/inode.c    |  4 ++--
 fs/erofs/xattr.c    |  2 +-
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h
index 2447ad4d0920..0782ba9da623 100644
--- a/fs/erofs/erofs_fs.h
+++ b/fs/erofs/erofs_fs.h
@@ -168,16 +168,24 @@ 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 d_icount)
+{
+	struct erofs_xattr_ibody_header *ibh;
+	unsigned int icount = le16_to_cpu(d_icount);
+
+	if (!icount)
+		return 0;
+
+	return struct_size(ibh, h_shared_xattrs, 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 {
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 80f4fe919ee7..cf31554075c9 100644
--- a/fs/erofs/inode.c
+++ b/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) ||
diff --git a/fs/erofs/xattr.c b/fs/erofs/xattr.c
index a8286998a079..7ef8d4bb45cd 100644
--- a/fs/erofs/xattr.c
+++ b/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 (unlikely(*tlimit < entry_sz)) {
-- 
2.17.1



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