ext4: refactor initialize_dirent_tail()

Move the calculation of the location of the dirent tail into
initialize_dirent_tail().  Also prefix the function with ext4_ to fix
kernel namepsace polution.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

3 files changed, 26 insertions, 41 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 5b86df7ec326..83128bdd7abb 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3147,8 +3147,8 @@ extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
                                  struct ext4_dir_entry_2 *de,
                                  int blocksize, int csum_size,
                                  unsigned int parent_ino, int dotdot_real_len);
-extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
-                                   unsigned int blocksize);
+extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
+                                        unsigned int blocksize);
 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
                                       struct buffer_head *bh);
 extern int ext4_ci_compare(const struct inode *parent,
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index f19dd5a08d0d..796137bb7dfa 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -1132,7 +1132,6 @@ static int ext4_finish_convert_inline_dir(handle_t *handle,
 {
         int err, csum_size = 0, header_size = 0;
         struct ext4_dir_entry_2 *de;
-        struct ext4_dir_entry_tail *t;
         void *target = dir_block->b_data;
 
         /*
@@ -1158,11 +1157,9 @@ static int ext4_finish_convert_inline_dir(handle_t *handle,
                         inline_size - EXT4_INLINE_DOTDOT_SIZE + header_size,
                         inode->i_sb->s_blocksize - csum_size);
 
-        if (csum_size) {
-                t = EXT4_DIRENT_TAIL(dir_block->b_data,
-                                     inode->i_sb->s_blocksize);
-                initialize_dirent_tail(t, inode->i_sb->s_blocksize);
-        }
+        if (csum_size)
+                ext4_initialize_dirent_tail(dir_block,
+                                            inode->i_sb->s_blocksize);
         set_buffer_uptodate(dir_block);
         err = ext4_handle_dirty_dirblock(handle, inode, dir_block);
         if (err)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 4f0bcbbcfe96..183ad614ae3d 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -293,9 +293,11 @@ static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
                              struct inode *dir, struct inode *inode);
 
 /* checksumming functions */
-void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
-                            unsigned int blocksize)
+void ext4_initialize_dirent_tail(struct buffer_head *bh,
+                                 unsigned int blocksize)
 {
+        struct ext4_dir_entry_tail *t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
+
         memset(t, 0, sizeof(struct ext4_dir_entry_tail));
         t->det_rec_len = ext4_rec_len_to_disk(
                         sizeof(struct ext4_dir_entry_tail), blocksize);
@@ -370,7 +372,7 @@ int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh)
         }
 
         if (t->det_checksum != ext4_dirblock_csum(inode, bh->b_data,
-                                                (char *)t - bh->b_data))
+                                                  (char *)t - bh->b_data))
                 return 0;
 
         return 1;
@@ -391,7 +393,7 @@ static void ext4_dirblock_csum_set(struct inode *inode,
         }
 
         t->det_checksum = ext4_dirblock_csum(inode, bh->b_data,
-                                           (char *)t - bh->b_data);
+                                             (char *)t - bh->b_data);
 }
 
 int ext4_handle_dirty_dirblock(handle_t *handle,
@@ -1813,7 +1815,6 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
         char *data1 = (*bh)->b_data, *data2;
         unsigned split, move, size;
         struct ext4_dir_entry_2 *de = NULL, *de2;
-        struct ext4_dir_entry_tail *t;
         int     csum_size = 0;
         int     err = 0, i;
 
@@ -1874,11 +1875,8 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
                                             (char *) de2,
                                             blocksize);
         if (csum_size) {
-                t = EXT4_DIRENT_TAIL(data2, blocksize);
-                initialize_dirent_tail(t, blocksize);
-
-                t = EXT4_DIRENT_TAIL(data1, blocksize);
-                initialize_dirent_tail(t, blocksize);
+                ext4_initialize_dirent_tail(*bh, blocksize);
+                ext4_initialize_dirent_tail(bh2, blocksize);
         }
 
         dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
@@ -2039,8 +2037,7 @@ static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
         struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
         struct dx_entry *entries;
         struct ext4_dir_entry_2 *de, *de2;
-        struct ext4_dir_entry_tail *t;
-        char            *data1, *top;
+        char            *data2, *top;
         unsigned        len;
         int             retval;
         unsigned        blocksize;
@@ -2080,21 +2077,18 @@ static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
                 return PTR_ERR(bh2);
         }
         ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
-        data1 = bh2->b_data;
+        data2 = bh2->b_data;
 
-        memcpy (data1, de, len);
-        de = (struct ext4_dir_entry_2 *) data1;
-        top = data1 + len;
+        memcpy(data2, de, len);
+        de = (struct ext4_dir_entry_2 *) data2;
+        top = data2 + len;
         while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
                 de = de2;
-        de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
-                                           (char *) de,
-                                           blocksize);
+        de->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
+                                           (char *) de, blocksize);
 
-        if (csum_size) {
-                t = EXT4_DIRENT_TAIL(data1, blocksize);
-                initialize_dirent_tail(t, blocksize);
-        }
+        if (csum_size)
+                ext4_initialize_dirent_tail(bh2, blocksize);
 
         /* Initialize the root; the dot dirents already exist */
         de = (struct ext4_dir_entry_2 *) (&root->dotdot);
@@ -2164,7 +2158,6 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
         struct inode *dir = d_inode(dentry->d_parent);
         struct buffer_head *bh = NULL;
         struct ext4_dir_entry_2 *de;
-        struct ext4_dir_entry_tail *t;
         struct super_block *sb;
         struct ext4_sb_info *sbi;
         struct ext4_filename fname;
@@ -2249,10 +2242,8 @@ add_to_new_block:
         de->inode = 0;
         de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
 
-        if (csum_size) {
-                t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
-                initialize_dirent_tail(t, blocksize);
-        }
+        if (csum_size)
+                ext4_initialize_dirent_tail(bh, blocksize);
 
         retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh);
 out:
@@ -2712,7 +2703,6 @@ static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
 {
         struct buffer_head *dir_block = NULL;
         struct ext4_dir_entry_2 *de;
-        struct ext4_dir_entry_tail *t;
         ext4_lblk_t block = 0;
         unsigned int blocksize = dir->i_sb->s_blocksize;
         int csum_size = 0;
@@ -2736,10 +2726,8 @@ static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
         de = (struct ext4_dir_entry_2 *)dir_block->b_data;
         ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
         set_nlink(inode, 2);
-        if (csum_size) {
-                t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
-                initialize_dirent_tail(t, blocksize);
-        }
+        if (csum_size)
+                ext4_initialize_dirent_tail(dir_block, blocksize);
 
         BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
         err = ext4_handle_dirty_dirblock(handle, inode, dir_block);