[PATCH v2 05/22] Squashfs: convert SQUASHFS_ID_* to inline functions

[Phillip Lougher <phillip@squashfs.org.uk>]

Convert old fashioned #define macros into inline functions.  This has
the following improvements:

1. Inline functions are typed, which makes the width and sigedness of
   input and outputs explicit, which reduces errors.

2. The inline functions enable more sanity checking to be added in
   later commits.

3. Inline functions are easier to read than #define macros, which
   improves code comprehension.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
 fs/squashfs/id.c               |  9 +++++----
 fs/squashfs/squashfs_fs.h      | 15 ---------------
 fs/squashfs/squashfs_helpers.h | 27 +++++++++++++++++++++++++++
 3 files changed, 32 insertions(+), 19 deletions(-)

diff --git a/fs/squashfs/id.c b/fs/squashfs/id.c
index ea5387679723..5630f5ec159a 100644
--- a/fs/squashfs/id.c
+++ b/fs/squashfs/id.c
@@ -24,6 +24,7 @@
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
+#include "squashfs_helpers.h"
 #include "squashfs.h"
 
 /*
@@ -33,8 +34,8 @@ int squashfs_get_id(struct super_block *sb, unsigned int index,
 					unsigned int *id)
 {
 	struct squashfs_sb_info *msblk = sb->s_fs_info;
-	int block = SQUASHFS_ID_BLOCK(index);
-	int offset = SQUASHFS_ID_BLOCK_OFFSET(index);
+	int block = squashfs_id_block(index);
+	int offset = squashfs_id_block_offset(index);
 	u64 start_block;
 	__le32 disk_id;
 	int err;
@@ -60,8 +61,8 @@ int squashfs_get_id(struct super_block *sb, unsigned int index,
 __le64 *squashfs_read_id_index_table(struct super_block *sb,
 		u64 id_table_start, u64 next_table, unsigned short no_ids)
 {
-	unsigned int length = SQUASHFS_ID_BLOCK_BYTES(no_ids);
-	unsigned int indexes = SQUASHFS_ID_BLOCKS(no_ids);
+	unsigned int length = squashfs_id_block_bytes(no_ids);
+	unsigned int indexes = squashfs_id_blocks(no_ids);
 	int n;
 	__le64 *table;
 	u64 start, end;
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
index 89b998f57a2b..25dd89a2c6ad 100644
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -107,21 +107,6 @@ static inline int squashfs_block_size(__le32 raw)
 	return (size >> 25) ? -EIO : size;
 }
 
-/* uid/gid lookup table defines */
-#define SQUASHFS_ID_BYTES(A)		((A) * sizeof(unsigned int))
-
-#define SQUASHFS_ID_BLOCK(A)		(SQUASHFS_ID_BYTES(A) / \
-					SQUASHFS_METADATA_SIZE)
-
-#define SQUASHFS_ID_BLOCK_OFFSET(A)	(SQUASHFS_ID_BYTES(A) % \
-					SQUASHFS_METADATA_SIZE)
-
-#define SQUASHFS_ID_BLOCKS(A)		((SQUASHFS_ID_BYTES(A) + \
-					SQUASHFS_METADATA_SIZE - 1) / \
-					SQUASHFS_METADATA_SIZE)
-
-#define SQUASHFS_ID_BLOCK_BYTES(A)	(SQUASHFS_ID_BLOCKS(A) *\
-					sizeof(u64))
 /* xattr id lookup table defines */
 #define SQUASHFS_XATTR_BYTES(A)		(((u64) (A)) * sizeof(struct squashfs_xattr_id))
 
diff --git a/fs/squashfs/squashfs_helpers.h b/fs/squashfs/squashfs_helpers.h
index aafc75a3a435..b9c517a50642 100644
--- a/fs/squashfs/squashfs_helpers.h
+++ b/fs/squashfs/squashfs_helpers.h
@@ -105,4 +105,31 @@ static inline s32 squashfs_lookup_block_bytes(u32 inodes)
 {
 	return squashfs_lookup_blocks(inodes) * sizeof(long long);
 }
+
+/* uid lookup table defines */
+static inline s32 squashfs_id_bytes(u16 ids)
+{
+	return (s32) ids * sizeof(unsigned int);
+}
+
+static inline s32 squashfs_id_block(u16 ids)
+{
+	return squashfs_id_bytes(ids) / SQUASHFS_METADATA_SIZE;
+}
+
+static inline s16 squashfs_id_block_offset(u16 ids)
+{
+	return squashfs_id_bytes(ids) % SQUASHFS_METADATA_SIZE;
+}
+
+static inline s8 squashfs_id_blocks(u16 ids)
+{
+	return (squashfs_id_bytes(ids) + (SQUASHFS_METADATA_SIZE - 1)) /
+		SQUASHFS_METADATA_SIZE;
+}
+
+static inline s16 squashfs_id_block_bytes(u16 ids)
+{
+	return squashfs_id_blocks(ids) * sizeof(long long);
+}
 #endif
-- 
2.47.3