ext4: create EXT4_MAX_BLOCKS() macro
Create a macro to calculate length + offset -> maximum blocks
This adds more readability.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 962a044..282a51b 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -262,6 +262,9 @@
(s)->s_first_ino)
#endif
#define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits)))
+#define EXT4_MAX_BLOCKS(size, offset, blkbits) \
+ ((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
+ blkbits))
/* Translate a block number to a cluster number */
#define EXT4_B2C(sbi, blk) ((blk) >> (sbi)->s_cluster_bits)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index ef28855..c930a01 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4961,13 +4961,8 @@
trace_ext4_fallocate_enter(inode, offset, len, mode);
lblk = offset >> blkbits;
- /*
- * We can't just convert len to max_blocks because
- * If blocksize = 4096 offset = 3072 and len = 2048
- */
- max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
- - lblk;
+ max_blocks = EXT4_MAX_BLOCKS(len, offset, blkbits);
flags = EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT;
if (mode & FALLOC_FL_KEEP_SIZE)
flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
@@ -5030,12 +5025,8 @@
unsigned int credits, blkbits = inode->i_blkbits;
map.m_lblk = offset >> blkbits;
- /*
- * We can't just convert len to max_blocks because
- * If blocksize = 4096 offset = 3072 and len = 2048
- */
- max_blocks = ((EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) -
- map.m_lblk);
+ max_blocks = EXT4_MAX_BLOCKS(len, offset, blkbits);
+
/*
* This is somewhat ugly but the idea is clear: When transaction is
* reserved, everything goes into it. Otherwise we rather start several
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 261ac37..34acda7 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -144,8 +144,7 @@
int err, len;
map.m_lblk = pos >> blkbits;
- map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
- - map.m_lblk;
+ map.m_len = EXT4_MAX_BLOCKS(length, pos, blkbits);
len = map.m_len;
err = ext4_map_blocks(NULL, inode, &map, 0);