Commit b4962091 authored by zhangyi (F)'s avatar zhangyi (F) Committed by Jan Kara
Browse files

ext2: propagate errors up to ext2_find_entry()'s callers 

The same to commit <36de9286> (ext4: propagate errors up to
ext4_find_entry()'s callers') in ext4, also return error instead of NULL
pointer in case of some error happens in ext2_find_entry() (e.g. -ENOMEM
or -EIO). This could avoid a negative dentry cache entry installed even
it failed to read directory block due to IO error.

Link: https://lore.kernel.org/r/20200608034043.10451-1-yi.zhang@huawei.com


Signed-off-by: default avatarzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent 1fcbcf06

fs/ext2/dir.c

+26 −27
Original line number Diff line number Diff line
@@ -348,7 +348,6 @@ struct ext2_dir_entry_2 *ext2_find_entry (struct inode *dir, 
	struct page *page = NULL;

	struct ext2_inode_info *ei = EXT2_I(dir);

	ext2_dirent * de;

	int dir_has_error = 0;



	if (npages == 0)

		goto out;
@@ -362,8 +361,10 @@ struct ext2_dir_entry_2 *ext2_find_entry (struct inode *dir, 
	n = start;

	do {

		char *kaddr;

		page = ext2_get_page(dir, n, dir_has_error);

		if (!IS_ERR(page)) {

		page = ext2_get_page(dir, n, 0);

		if (IS_ERR(page))

			return ERR_CAST(page);



		kaddr = page_address(page);

		de = (ext2_dirent *) kaddr;

		kaddr += ext2_last_byte(dir, n) - reclen;
@@ -379,8 +380,6 @@ struct ext2_dir_entry_2 *ext2_find_entry (struct inode *dir, 
			de = ext2_next_entry(de);

		}

		ext2_put_page(page);

		} else

			dir_has_error = 1;



		if (++n >= npages)

			n = 0;
@@ -414,18 +413,18 @@ struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p) 
	return de;

}



ino_t ext2_inode_by_name(struct inode *dir, const struct qstr *child)

int ext2_inode_by_name(struct inode *dir, const struct qstr *child, ino_t *ino)

{

	ino_t res = 0;

	struct ext2_dir_entry_2 *de;

	struct page *page;

	

	de = ext2_find_entry(dir, child, &page);

	if (de) {

		res = le32_to_cpu(de->inode);

	if (IS_ERR_OR_NULL(de))

		return PTR_ERR(de);



	*ino = le32_to_cpu(de->inode);

	ext2_put_page(page);

	}

	return res;

	return 0;

}



static int ext2_prepare_chunk(struct page *page, loff_t pos, unsigned len)

fs/ext2/ext2.h

+2 −1
Original line number Diff line number Diff line
@@ -738,7 +738,8 @@ extern void ext2_rsv_window_add(struct super_block *sb, struct ext2_reserve_wind 


/* dir.c */

extern int ext2_add_link (struct dentry *, struct inode *);

extern ino_t ext2_inode_by_name(struct inode *, const struct qstr *);

extern int ext2_inode_by_name(struct inode *dir,

			      const struct qstr *child, ino_t *ino);

extern int ext2_make_empty(struct inode *, struct inode *);

extern struct ext2_dir_entry_2 * ext2_find_entry (struct inode *,const struct qstr *, struct page **);

extern int ext2_delete_entry (struct ext2_dir_entry_2 *, struct page *);

fs/ext2/namei.c

+26 −6
Original line number Diff line number Diff line
@@ -56,12 +56,15 @@ static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode) 
static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)

{

	struct inode * inode;

	ino_t ino;

	ino_t ino = 0;

	int res;

	

	if (dentry->d_name.len > EXT2_NAME_LEN)

		return ERR_PTR(-ENAMETOOLONG);



	ino = ext2_inode_by_name(dir, &dentry->d_name);

	res = ext2_inode_by_name(dir, &dentry->d_name, &ino);

	if (res)

		return ERR_PTR(res);

	inode = NULL;

	if (ino) {

		inode = ext2_iget(dir->i_sb, ino);
@@ -78,7 +81,12 @@ static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, uns 
struct dentry *ext2_get_parent(struct dentry *child)

{

	struct qstr dotdot = QSTR_INIT("..", 2);

	unsigned long ino = ext2_inode_by_name(d_inode(child), &dotdot);

	ino_t ino = 0;

	int res;



	res = ext2_inode_by_name(d_inode(child), &dotdot, &ino);

	if (res)

		return ERR_PTR(res);

	if (!ino)

		return ERR_PTR(-ENOENT);

	return d_obtain_alias(ext2_iget(child->d_sb, ino));
@@ -275,6 +283,10 @@ static int ext2_unlink(struct inode * dir, struct dentry *dentry) 
		goto out;



	de = ext2_find_entry(dir, &dentry->d_name, &page);

	if (IS_ERR(de)) {

		err = PTR_ERR(de);

		goto out;

	}

	if (!de) {

		err = -ENOENT;

		goto out;
@@ -331,6 +343,10 @@ static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, 
		goto out;



	old_de = ext2_find_entry(old_dir, &old_dentry->d_name, &old_page);

	if (IS_ERR(old_de)) {

		err = PTR_ERR(old_de);

		goto out;

	}

	if (!old_de) {

		err = -ENOENT;

		goto out;
@@ -353,6 +369,10 @@ static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, 


		err = -ENOENT;

		new_de = ext2_find_entry(new_dir, &new_dentry->d_name, &new_page);

		if (IS_ERR(new_de)) {

			err = PTR_ERR(new_de);

			goto out_dir;

		}

		if (!new_de)

			goto out_dir;

		ext2_set_link(new_dir, new_de, new_page, old_inode, 1);