ext4: miscellaneous error checks and coding cleanups for mballoc

ext4_mb_seq_history_open(): check if sbi->s_mb_history is NULL

ext4_mb_history_init(): replace kmalloc and memset with kzalloc

ext4_mb_init_backend(): remove memset since kzalloc is used

ext4_mb_init(): the return value of ext4_mb_init_backend is int,
	but i is unsigned, replace it with a new int variable.

Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index b64600be2066faced9b8a8a50b750e02152f08f4..6d69dd92aadb6d46bb60b7c96a5ec3996a3e950f 100644 (file)
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1985,6 +1985,8 @@ static int ext4_mb_seq_history_open(struct inode *inode, struct file *file)
        int rc;
        int size;
 
+       if (unlikely(sbi->s_mb_history == NULL))
+               return -ENOMEM;
        s = kmalloc(sizeof(*s), GFP_KERNEL);
        if (s == NULL)
                return -ENOMEM;
@@ -2187,9 +2189,7 @@ static void ext4_mb_history_init(struct super_block *sb)
        sbi->s_mb_history_cur = 0;
        spin_lock_init(&sbi->s_mb_history_lock);
        i = sbi->s_mb_history_max * sizeof(struct ext4_mb_history);
-       sbi->s_mb_history = kmalloc(i, GFP_KERNEL);
-       if (likely(sbi->s_mb_history != NULL))
-               memset(sbi->s_mb_history, 0, i);
+       sbi->s_mb_history = kzalloc(i, GFP_KERNEL);
        /* if we can't allocate history, then we simple won't use it */
 }
 
@@ -2303,7 +2303,6 @@ static int ext4_mb_init_backend(struct super_block *sb)
                        i++;
                        goto err_freebuddy;
                }
-               memset(meta_group_info[j], 0, len);
                set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT,
                        &(meta_group_info[j]->bb_state));
 
@@ -2358,6 +2357,7 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
        unsigned i;
        unsigned offset;
        unsigned max;
+       int ret;
 
        if (!test_opt(sb, MBALLOC))
                return 0;
@@ -2392,12 +2392,12 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
        } while (i <= sb->s_blocksize_bits + 1);
 
        /* init file for buddy data */
-       i = ext4_mb_init_backend(sb);
-       if (i) {
+       ret = ext4_mb_init_backend(sb);
+       if (ret != 0) {
                clear_opt(sbi->s_mount_opt, MBALLOC);
                kfree(sbi->s_mb_offsets);
                kfree(sbi->s_mb_maxs);
-               return i;
+               return ret;
        }
 
        spin_lock_init(&sbi->s_md_lock);