ext4: Introduce ext4_lblk_t

This patch adds a new data type ext4_lblk_t to represent
the logical file blocks.

This is the preparatory patch to support large files in ext4
The follow up patch with convert the ext4_inode i_blocks to
represent the number of blocks in file system block size. This
changes makes it possible to have a block number 2**32 -1 which
will result in overflow if the block number is represented by
signed long. This patch convert all the block number to type
ext4_lblk_t which is typedef to __u32

Also remove dead code ext4_ext_walk_space

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>

1 files changed, 19 insertions, 10 deletions

diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h
index fb31c1aba98..5e2da0974d1 100644
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -935,11 +935,14 @@ extern unsigned long ext4_count_free (struct buffer_head *, unsigned);
 /* inode.c */
 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
                 struct buffer_head *bh, ext4_fsblk_t blocknr);
-struct buffer_head * ext4_getblk (handle_t *, struct inode *, long, int, int *);
-struct buffer_head * ext4_bread (handle_t *, struct inode *, int, int, int *);
+struct buffer_head *ext4_getblk(handle_t *, struct inode *,
+                                                ext4_lblk_t, int, int *);
+struct buffer_head *ext4_bread(handle_t *, struct inode *,
+                                                ext4_lblk_t, int, int *);
 int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
-        sector_t iblock, unsigned long maxblocks, struct buffer_head *bh_result,
-        int create, int extend_disksize);
+                                ext4_lblk_t iblock, unsigned long maxblocks,
+                                struct buffer_head *bh_result,
+                                int create, int extend_disksize);
 
 extern void ext4_read_inode (struct inode *);
 extern int  ext4_write_inode (struct inode *, int);
@@ -1068,7 +1071,7 @@ extern const struct inode_operations ext4_fast_symlink_inode_operations;
 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
-                        ext4_fsblk_t iblock,
+                        ext4_lblk_t iblock,
                         unsigned long max_blocks, struct buffer_head *bh_result,
                         int create, int extend_disksize);
 extern void ext4_ext_truncate(struct inode *, struct page *);
@@ -1081,11 +1084,17 @@ ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
                         unsigned long max_blocks, struct buffer_head *bh,
                         int create, int extend_disksize)
 {
-        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
-                return ext4_ext_get_blocks(handle, inode, block, max_blocks,
-                                        bh, create, extend_disksize);
-        return ext4_get_blocks_handle(handle, inode, block, max_blocks, bh,
-                                        create, extend_disksize);
+        int retval;
+        if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
+                retval = ext4_ext_get_blocks(handle, inode,
+                                                (ext4_lblk_t)block, max_blocks,
+                                                bh, create, extend_disksize);
+        } else {
+                retval = ext4_get_blocks_handle(handle, inode,
+                                                (ext4_lblk_t)block, max_blocks,
+                                                bh, create, extend_disksize);
+        }
+        return retval;
 }