[PATCH v2] fs-fat: Less function calls in fat_fill_super() after error detection

SF Markus Elfring
2014-11-29T06:45:10Z

From: Markus Elfring <elfring@users.sourceforge.net>
Date: Sat, 29 Nov 2014 07:37:34 +0100

The iput() function was called in an inefficient way by the implementation
of the fat_fill_super() function in case of an allocation failure.
The corresponding source code was improved by deletion of two unnecessary
null pointer checks and a few adjustments for jump labels.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
fs/fat/inode.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 756aead..a39afe8 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -1716,20 +1716,20 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,

fsinfo_inode = new_inode(sb);
if (!fsinfo_inode)
- goto out_fail;
+ goto fsinfo_inode_failure;
fsinfo_inode->i_ino = MSDOS_FSINFO_INO;
sbi->fsinfo_inode = fsinfo_inode;
insert_inode_hash(fsinfo_inode);

root_inode = new_inode(sb);
if (!root_inode)
- goto out_fail;
+ goto failure_exit;
root_inode->i_ino = MSDOS_ROOT_INO;
root_inode->i_version = 1;
error = fat_read_root(root_inode);
if (error < 0) {
iput(root_inode);
- goto out_fail;
+ goto failure_exit;
}
error = -ENOMEM;
insert_inode_hash(root_inode);
@@ -1737,7 +1737,7 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
sb->s_root = d_make_root(root_inode);
if (!sb->s_root) {
fat_msg(sb, KERN_ERR, "get root inode failed");
- goto out_fail;
+ goto failure_exit;
}

if (sbi->options.discard) {
@@ -1756,11 +1756,13 @@ out_invalid:
if (!silent)
fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem");

+failure_exit:
+ iput(fsinfo_inode);
+
+fsinfo_inode_failure:
+ iput(fat_inode);
+
out_fail:
- if (fsinfo_inode)
- iput(fsinfo_inode);
- if (fat_inode)
- iput(fat_inode);
unload_nls(sbi->nls_io);
unload_nls(sbi->nls_disk);
if (sbi->options.iocharset != fat_default_iocharset)
--
2.1.3