[PATCH 04/18] Squashfs: convert SQUASHFS_LOOKUP_* 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/export.c           |  9 +++++----
 fs/squashfs/squashfs_fs.h      | 16 ----------------
 fs/squashfs/squashfs_helpers.h | 27 +++++++++++++++++++++++++++
 3 files changed, 32 insertions(+), 20 deletions(-)

diff --git a/fs/squashfs/export.c b/fs/squashfs/export.c
index 62972f0ff868..ad7cc882d789 100644
--- a/fs/squashfs/export.c
+++ b/fs/squashfs/export.c
@@ -31,6 +31,7 @@
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
 #include "squashfs_fs_i.h"
+#include "squashfs_helpers.h"
 #include "squashfs.h"
 
 /*
@@ -39,8 +40,8 @@
 static long long squashfs_inode_lookup(struct super_block *sb, int ino_num)
 {
 	struct squashfs_sb_info *msblk = sb->s_fs_info;
-	int blk = SQUASHFS_LOOKUP_BLOCK(ino_num - 1);
-	int offset = SQUASHFS_LOOKUP_BLOCK_OFFSET(ino_num - 1);
+	int blk = squashfs_lookup_block(ino_num - 1);
+	int offset = squashfs_lookup_block_offset(ino_num - 1);
 	u64 start;
 	__le64 ino;
 	int err;
@@ -115,8 +116,8 @@ static struct dentry *squashfs_get_parent(struct dentry *child)
 __le64 *squashfs_read_inode_lookup_table(struct super_block *sb,
 		u64 lookup_table_start, u64 next_table, unsigned int inodes)
 {
-	unsigned int length = SQUASHFS_LOOKUP_BLOCK_BYTES(inodes);
-	unsigned int indexes = SQUASHFS_LOOKUP_BLOCKS(inodes);
+	unsigned int length = squashfs_lookup_block_bytes(inodes);
+	unsigned int indexes = squashfs_lookup_blocks(inodes);
 	int n;
 	__le64 *table;
 	u64 start, end;
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
index 3dbd174b5f21..89b998f57a2b 100644
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -107,22 +107,6 @@ static inline int squashfs_block_size(__le32 raw)
 	return (size >> 25) ? -EIO : size;
 }
 
-/* inode lookup table defines */
-#define SQUASHFS_LOOKUP_BYTES(A)	((A) * sizeof(u64))
-
-#define SQUASHFS_LOOKUP_BLOCK(A)	(SQUASHFS_LOOKUP_BYTES(A) / \
-					SQUASHFS_METADATA_SIZE)
-
-#define SQUASHFS_LOOKUP_BLOCK_OFFSET(A)	(SQUASHFS_LOOKUP_BYTES(A) % \
-					SQUASHFS_METADATA_SIZE)
-
-#define SQUASHFS_LOOKUP_BLOCKS(A)	((SQUASHFS_LOOKUP_BYTES(A) + \
-					SQUASHFS_METADATA_SIZE - 1) / \
-					SQUASHFS_METADATA_SIZE)
-
-#define SQUASHFS_LOOKUP_BLOCK_BYTES(A)	(SQUASHFS_LOOKUP_BLOCKS(A) *\
-					sizeof(u64))
-
 /* uid/gid lookup table defines */
 #define SQUASHFS_ID_BYTES(A)		((A) * sizeof(unsigned int))
 
diff --git a/fs/squashfs/squashfs_helpers.h b/fs/squashfs/squashfs_helpers.h
index b99ca67c729a..aafc75a3a435 100644
--- a/fs/squashfs/squashfs_helpers.h
+++ b/fs/squashfs/squashfs_helpers.h
@@ -78,4 +78,31 @@ static inline s32 squashfs_fragment_index_bytes(u32 fragments)
 {
 	return squashfs_fragment_indexes(fragments) * sizeof(long long);
 }
+
+/* inode lookup table defines */
+static inline s64 squashfs_lookup_bytes(u32 inodes)
+{
+	return (s64) inodes * sizeof(s64);
+}
+
+static inline s32 squashfs_lookup_block(u32 inodes)
+{
+	return squashfs_lookup_bytes(inodes) / SQUASHFS_METADATA_SIZE;
+}
+
+static inline s16 squashfs_lookup_block_offset(u32 inodes)
+{
+	return squashfs_lookup_bytes(inodes) % SQUASHFS_METADATA_SIZE;
+}
+
+static inline s32 squashfs_lookup_blocks(u32 inodes)
+{
+	return (squashfs_lookup_bytes(inodes) + (SQUASHFS_METADATA_SIZE - 1)) /
+		SQUASHFS_METADATA_SIZE;
+}
+
+static inline s32 squashfs_lookup_block_bytes(u32 inodes)
+{
+	return squashfs_lookup_blocks(inodes) * sizeof(long long);
+}
 #endif
-- 
2.47.3