ext4: use ERR_PTR() abstraction for ext4_append()

Use ERR_PTR()/IS_ERR() abstraction instead of passing in a separate
pointer to an integer for the error code, as a code cleanup.

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

2 files changed, 33 insertions, 34 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index c4e9177f60c6..f4466c3650dc 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -707,6 +707,8 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
         /* ensure we send some value back into *errp */
         *errp = 0;
 
+        if (create && err == 0)
+                err = -ENOSPC;  /* should never happen */
         if (err < 0)
                 *errp = err;
         if (err <= 0)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 0e28c749e273..f58c053d13e0 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -51,34 +51,28 @@
 
 static struct buffer_head *ext4_append(handle_t *handle,
                                         struct inode *inode,
-                                        ext4_lblk_t *block, int *err)
+                                        ext4_lblk_t *block)
 {
         struct buffer_head *bh;
+        int err = 0;
 
         if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
                      ((inode->i_size >> 10) >=
-                      EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) {
-                *err = -ENOSPC;
-                return NULL;
-        }
+                      EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))
+                return ERR_PTR(-ENOSPC);
 
         *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
 
-        bh = ext4_bread(handle, inode, *block, 1, err);
-        if (bh) {
-                inode->i_size += inode->i_sb->s_blocksize;
-                EXT4_I(inode)->i_disksize = inode->i_size;
-                *err = ext4_journal_get_write_access(handle, bh);
-                if (*err) {
-                        brelse(bh);
-                        bh = NULL;
-                }
-        }
-        if (!bh && !(*err)) {
-                *err = -EIO;
-                ext4_error(inode->i_sb,
-                           "Directory hole detected on inode %lu\n",
-                           inode->i_ino);
+        bh = ext4_bread(handle, inode, *block, 1, &err);
+        if (!bh)
+                return ERR_PTR(err);
+        inode->i_size += inode->i_sb->s_blocksize;
+        EXT4_I(inode)->i_disksize = inode->i_size;
+        err = ext4_journal_get_write_access(handle, bh);
+        if (err) {
+                brelse(bh);
+                ext4_std_error(inode->i_sb, err);
+                return ERR_PTR(err);
         }
         return bh;
 }
@@ -1555,11 +1549,12 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
                 csum_size = sizeof(struct ext4_dir_entry_tail);
 
-        bh2 = ext4_append (handle, dir, &newblock, &err);
-        if (!(bh2)) {
+        bh2 = ext4_append(handle, dir, &newblock);
+        if (IS_ERR(bh2)) {
                 brelse(*bh);
                 *bh = NULL;
-                goto errout;
+                *error = PTR_ERR(bh2);
+                return NULL;
         }
 
         BUFFER_TRACE(*bh, "get_write_access");
@@ -1640,7 +1635,6 @@ journal_error:
         brelse(bh2);
         *bh = NULL;
         ext4_std_error(dir->i_sb, err);
-errout:
         *error = err;
         return NULL;
 }
@@ -1815,10 +1809,10 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
         len = ((char *) root) + (blocksize - csum_size) - (char *) de;
 
         /* Allocate new block for the 0th block's dirents */
-        bh2 = ext4_append(handle, dir, &block, &retval);
-        if (!(bh2)) {
+        bh2 = ext4_append(handle, dir, &block);
+        if (IS_ERR(bh2)) {
                 brelse(bh);
-                return retval;
+                return PTR_ERR(bh2);
         }
         ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
         data1 = bh2->b_data;
@@ -1950,9 +1944,9 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
                         return make_indexed_dir(handle, dentry, inode, bh);
                 brelse(bh);
         }
-        bh = ext4_append(handle, dir, &block, &retval);
-        if (!bh)
-                return retval;
+        bh = ext4_append(handle, dir, &block);
+        if (IS_ERR(bh))
+                return PTR_ERR(bh);
         de = (struct ext4_dir_entry_2 *) bh->b_data;
         de->inode = 0;
         de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
@@ -2023,9 +2017,11 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
                         err = -ENOSPC;
                         goto cleanup;
                 }
-                bh2 = ext4_append (handle, dir, &newblock, &err);
-                if (!(bh2))
+                bh2 = ext4_append(handle, dir, &newblock);
+                if (IS_ERR(bh2)) {
+                        err = PTR_ERR(bh2);
                         goto cleanup;
+                }
                 node2 = (struct dx_node *)(bh2->b_data);
                 entries2 = node2->entries;
                 memset(&node2->fake, 0, sizeof(struct fake_dirent));
@@ -2364,8 +2360,9 @@ static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
         }
 
         inode->i_size = 0;
-        if (!(dir_block = ext4_append(handle, inode, &block, &err)))
-                goto out;
+        dir_block = ext4_append(handle, inode, &block);
+        if (IS_ERR(dir_block))
+                return PTR_ERR(dir_block);
         BUFFER_TRACE(dir_block, "get_write_access");
         err = ext4_journal_get_write_access(handle, dir_block);
         if (err)