JBD2/Ext4: Convert kmalloc to kzalloc in jbd2/ext4

Convert kmalloc to kzalloc() and get rid of the memset().

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index b10d68f..12c7d65 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -750,12 +750,11 @@
 		}
 	} else {
 		/* Allocate a buffer where we construct the new block. */
-		s->base = kmalloc(sb->s_blocksize, GFP_KERNEL);
+		s->base = kzalloc(sb->s_blocksize, GFP_KERNEL);
 		/* assert(header == s->base) */
 		error = -ENOMEM;
 		if (s->base == NULL)
 			goto cleanup;
-		memset(s->base, 0, sb->s_blocksize);
 		header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
 		header(s->base)->h_blocks = cpu_to_le32(1);
 		header(s->base)->h_refcount = cpu_to_le32(1);
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 0e329a3..f12c65b 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -654,10 +654,9 @@
 	journal_t *journal;
 	int err;
 
-	journal = kmalloc(sizeof(*journal), GFP_KERNEL);
+	journal = kzalloc(sizeof(*journal), GFP_KERNEL|__GFP_NOFAIL);
 	if (!journal)
 		goto fail;
-	memset(journal, 0, sizeof(*journal));
 
 	init_waitqueue_head(&journal->j_wait_transaction_locked);
 	init_waitqueue_head(&journal->j_wait_logspace);
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index a5fb70f..b1fcf2b 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -96,13 +96,12 @@
 
 alloc_transaction:
 	if (!journal->j_running_transaction) {
-		new_transaction = kmalloc(sizeof(*new_transaction),
+		new_transaction = kzalloc(sizeof(*new_transaction),
 						GFP_NOFS|__GFP_NOFAIL);
 		if (!new_transaction) {
 			ret = -ENOMEM;
 			goto out;
 		}
-		memset(new_transaction, 0, sizeof(*new_transaction));
 	}
 
 	jbd_debug(3, "New handle %p going live.\n", handle);