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 962a0444dc84a6fd548ebf04bf2ed285d3c49da2..282a51b07c5769e89a2064e12dfad53650183614 100644 (file)
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -262,6 +262,9 @@ struct ext4_io_submit {
                                 (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 ef288558b8692ef60a6cf6aa91d5f11fd3513726..c930a0110fb4f6ecc19819d1728879277b9e8843 100644 (file)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4961,13 +4961,8 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 
        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 @@ int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
        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 261ac3734c580a9b555f0e8f5e24fe56ce7ec047..34acda78ce25ee8ee097c148b2c061d682f56a1a 100644 (file)
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -144,8 +144,7 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                        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);