ext4: use IS_ERR instead of IS_ERR_OR_NULL and set inode null when IS_ERR

1: ext4_iget/ext4_find_extent never returns NULL, use IS_ERR
instead of IS_ERR_OR_NULL to fix this.

2: ext4_fc_replay_inode should set the inode to NULL when IS_ERR.
and go to call iput properly.

Fixes: 8016e29 ("ext4: fast commit recovery path")
Signed-off-by: Yi Li <yili@winhong.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201230033827.3996064-1-yili@winhong.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

Author: cybertan

fs/ext4/fast_commit.c

@@ -1318,14 +1318,14 @@ static int ext4_fc_replay_unlink(struct super_block *sb, struct ext4_fc_tl *tl)
 	entry.len = darg.dname_len;
 	inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
 
-	if (IS_ERR_OR_NULL(inode)) {
+	if (IS_ERR(inode)) {
 		jbd_debug(1, "Inode %d not found", darg.ino);
 		return 0;
 	}
 
 	old_parent = ext4_iget(sb, darg.parent_ino,
 				EXT4_IGET_NORMAL);
-	if (IS_ERR_OR_NULL(old_parent)) {
+	if (IS_ERR(old_parent)) {
 		jbd_debug(1, "Dir with inode  %d not found", darg.parent_ino);
 		iput(inode);
 		return 0;
@@ -1410,7 +1410,7 @@ static int ext4_fc_replay_link(struct super_block *sb, struct ext4_fc_tl *tl)
 			darg.parent_ino, darg.dname_len);
 
 	inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
-	if (IS_ERR_OR_NULL(inode)) {
+	if (IS_ERR(inode)) {
 		jbd_debug(1, "Inode not found.");
 		return 0;
 	}
@@ -1466,10 +1466,11 @@ static int ext4_fc_replay_inode(struct super_block *sb, struct ext4_fc_tl *tl)
 	trace_ext4_fc_replay(sb, tag, ino, 0, 0);
 
 	inode = ext4_iget(sb, ino, EXT4_IGET_NORMAL);
-	if (!IS_ERR_OR_NULL(inode)) {
+	if (!IS_ERR(inode)) {
 		ext4_ext_clear_bb(inode);
 		iput(inode);
 	}
+	inode = NULL;
 
 	ext4_fc_record_modified_inode(sb, ino);
 
@@ -1512,7 +1513,7 @@ static int ext4_fc_replay_inode(struct super_block *sb, struct ext4_fc_tl *tl)
 
 	/* Given that we just wrote the inode on disk, this SHOULD succeed. */
 	inode = ext4_iget(sb, ino, EXT4_IGET_NORMAL);
-	if (IS_ERR_OR_NULL(inode)) {
+	if (IS_ERR(inode)) {
 		jbd_debug(1, "Inode not found.");
 		return -EFSCORRUPTED;
 	}
@@ -1564,7 +1565,7 @@ static int ext4_fc_replay_create(struct super_block *sb, struct ext4_fc_tl *tl)
 		goto out;
 
 	inode = ext4_iget(sb, darg.ino, EXT4_IGET_NORMAL);
-	if (IS_ERR_OR_NULL(inode)) {
+	if (IS_ERR(inode)) {
 		jbd_debug(1, "inode %d not found.", darg.ino);
 		inode = NULL;
 		ret = -EINVAL;
@@ -1577,7 +1578,7 @@ static int ext4_fc_replay_create(struct super_block *sb, struct ext4_fc_tl *tl)
 		 * dot and dot dot dirents are setup properly.
 		 */
 		dir = ext4_iget(sb, darg.parent_ino, EXT4_IGET_NORMAL);
-		if (IS_ERR_OR_NULL(dir)) {
+		if (IS_ERR(dir)) {
 			jbd_debug(1, "Dir %d not found.", darg.ino);
 			goto out;
 		}
@@ -1653,7 +1654,7 @@ static int ext4_fc_replay_add_range(struct super_block *sb,
 
 	inode = ext4_iget(sb, le32_to_cpu(fc_add_ex->fc_ino),
 				EXT4_IGET_NORMAL);
-	if (IS_ERR_OR_NULL(inode)) {
+	if (IS_ERR(inode)) {
 		jbd_debug(1, "Inode not found.");
 		return 0;
 	}
@@ -1777,7 +1778,7 @@ ext4_fc_replay_del_range(struct super_block *sb, struct ext4_fc_tl *tl)
 		le32_to_cpu(lrange->fc_ino), cur, remaining);
 
 	inode = ext4_iget(sb, le32_to_cpu(lrange->fc_ino), EXT4_IGET_NORMAL);
-	if (IS_ERR_OR_NULL(inode)) {
+	if (IS_ERR(inode)) {
 		jbd_debug(1, "Inode %d not found", le32_to_cpu(lrange->fc_ino));
 		return 0;
 	}
@@ -1832,7 +1833,7 @@ static void ext4_fc_set_bitmaps_and_counters(struct super_block *sb)
 	for (i = 0; i < state->fc_modified_inodes_used; i++) {
 		inode = ext4_iget(sb, state->fc_modified_inodes[i],
 			EXT4_IGET_NORMAL);
-		if (IS_ERR_OR_NULL(inode)) {
+		if (IS_ERR(inode)) {
 			jbd_debug(1, "Inode %d not found.",
 				state->fc_modified_inodes[i]);
 			continue;
@@ -1849,7 +1850,7 @@ static void ext4_fc_set_bitmaps_and_counters(struct super_block *sb)
 
 			if (ret > 0) {
 				path = ext4_find_extent(inode, map.m_lblk, NULL, 0);
-				if (!IS_ERR_OR_NULL(path)) {
+				if (!IS_ERR(path)) {
 					for (j = 0; j < path->p_depth; j++)
 						ext4_mb_mark_bb(inode->i_sb,
 							path[j].p_block, 1, 1);