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Commit 00e4e6b3 authored by Chris Mason's avatar Chris Mason
Browse files

Get rid of BTRFS_I(inode)->index and use local vars instead 



rename and link don't always have a lock on the source inode, and
our use of a per-inode index variable was racy.  This changes things to
store the index in a local variable instead.

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 7d2b4daa

fs/btrfs/btrfs_inode.h

+0 −9
Original line number Diff line number Diff line
@@ -57,15 +57,6 @@ struct btrfs_inode { 
	 * number for new files that are created

	 */

	u64 index_cnt;



	/*

	 * index holds the directory index for this inode on creation, so

	 * add_link can do what its supposed to.  This isn't populated when the

	 * inode is read because there isn't really a reason to know this unless

	 * we are creating the directory index or deleting it, and deletion

	 * reads the index off of the inode reference at unlink time.

	 */

	u64 index;

};



static inline struct btrfs_inode *BTRFS_I(struct inode *inode)

fs/btrfs/inode.c

+34 −25
Original line number Diff line number Diff line
@@ -2153,7 +2153,8 @@ static int btrfs_set_inode_index_count(struct inode *inode) 
	return ret;

}



static int btrfs_set_inode_index(struct inode *dir, struct inode *inode)

static int btrfs_set_inode_index(struct inode *dir, struct inode *inode,

				 u64 *index)

{

	int ret = 0;
@@ -2163,7 +2164,7 @@ static int btrfs_set_inode_index(struct inode *dir, struct inode *inode) 
			return ret;

	}



	BTRFS_I(inode)->index = BTRFS_I(dir)->index_cnt;

	*index = BTRFS_I(dir)->index_cnt;

	BTRFS_I(dir)->index_cnt++;



	return ret;
@@ -2176,7 +2177,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, 
				     u64 ref_objectid,

				     u64 objectid,

				     struct btrfs_block_group_cache *group,

				     int mode)

				     int mode, u64 *index)

{

	struct inode *inode;

	struct btrfs_inode_item *inode_item;
@@ -2198,11 +2199,9 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, 
		return ERR_PTR(-ENOMEM);



	if (dir) {

		ret = btrfs_set_inode_index(dir, inode);

		ret = btrfs_set_inode_index(dir, inode, index);

		if (ret)

			return ERR_PTR(ret);

	} else {

		BTRFS_I(inode)->index = 0;

	}

	/*

	 * index_cnt is ignored for everything but a dir,
@@ -2268,7 +2267,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, 
	ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,

			     struct btrfs_inode_ref);

	btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);

	btrfs_set_inode_ref_index(path->nodes[0], ref, BTRFS_I(inode)->index);

	btrfs_set_inode_ref_index(path->nodes[0], ref, *index);

	ptr = (unsigned long)(ref + 1);

	write_extent_buffer(path->nodes[0], name, ptr, name_len);
@@ -2296,7 +2295,7 @@ static inline u8 btrfs_inode_type(struct inode *inode) 


static int btrfs_add_link(struct btrfs_trans_handle *trans,

			    struct dentry *dentry, struct inode *inode,

			    int add_backref)

			    int add_backref, u64 index)

{

	int ret;

	struct btrfs_key key;
@@ -2311,7 +2310,7 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans, 
				    dentry->d_name.name, dentry->d_name.len,

				    dentry->d_parent->d_inode->i_ino,

				    &key, btrfs_inode_type(inode),

				    BTRFS_I(inode)->index);

				    index);

	if (ret == 0) {

		if (add_backref) {

			ret = btrfs_insert_inode_ref(trans, root,
@@ -2319,7 +2318,7 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans, 
					     dentry->d_name.len,

					     inode->i_ino,

					     parent_inode->i_ino,

					     BTRFS_I(inode)->index);

					     index);

		}

		btrfs_i_size_write(parent_inode, parent_inode->i_size +

				   dentry->d_name.len * 2);
@@ -2332,9 +2331,9 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans, 


static int btrfs_add_nondir(struct btrfs_trans_handle *trans,

			    struct dentry *dentry, struct inode *inode,

			    int backref)

			    int backref, u64 index)

{

	int err = btrfs_add_link(trans, dentry, inode, backref);

	int err = btrfs_add_link(trans, dentry, inode, backref, index);

	if (!err) {

		d_instantiate(dentry, inode);

		return 0;
@@ -2354,6 +2353,7 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry, 
	int drop_inode = 0;

	u64 objectid;

	unsigned long nr = 0;

	u64 index = 0;



	if (!new_valid_dev(rdev))

		return -EINVAL;
@@ -2374,7 +2374,7 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry, 
	inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,

				dentry->d_name.len,

				dentry->d_parent->d_inode->i_ino, objectid,

				BTRFS_I(dir)->block_group, mode);

				BTRFS_I(dir)->block_group, mode, &index);

	err = PTR_ERR(inode);

	if (IS_ERR(inode))

		goto out_unlock;
@@ -2386,7 +2386,7 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry, 
	}



	btrfs_set_trans_block_group(trans, inode);

	err = btrfs_add_nondir(trans, dentry, inode, 0);

	err = btrfs_add_nondir(trans, dentry, inode, 0, index);

	if (err)

		drop_inode = 1;

	else {
@@ -2419,6 +2419,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, 
	int drop_inode = 0;

	unsigned long nr = 0;

	u64 objectid;

	u64 index = 0;



	err = btrfs_check_free_space(root, 1, 0);

	if (err)
@@ -2435,7 +2436,8 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, 
	inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,

				dentry->d_name.len,

				dentry->d_parent->d_inode->i_ino,

				objectid, BTRFS_I(dir)->block_group, mode);

				objectid, BTRFS_I(dir)->block_group, mode,

				&index);

	err = PTR_ERR(inode);

	if (IS_ERR(inode))

		goto out_unlock;
@@ -2447,7 +2449,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, 
	}



	btrfs_set_trans_block_group(trans, inode);

	err = btrfs_add_nondir(trans, dentry, inode, 0);

	err = btrfs_add_nondir(trans, dentry, inode, 0, index);

	if (err)

		drop_inode = 1;

	else {
@@ -2489,6 +2491,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir, 
	struct btrfs_trans_handle *trans;

	struct btrfs_root *root = BTRFS_I(dir)->root;

	struct inode *inode = old_dentry->d_inode;

	u64 index;

	unsigned long nr = 0;

	int err;

	int drop_inode = 0;
@@ -2504,7 +2507,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir, 
	err = btrfs_check_free_space(root, 1, 0);

	if (err)

		goto fail;

	err = btrfs_set_inode_index(dir, inode);

	err = btrfs_set_inode_index(dir, inode, &index);

	if (err)

		goto fail;
@@ -2513,7 +2516,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir, 
	btrfs_set_trans_block_group(trans, dir);

	atomic_inc(&inode->i_count);



	err = btrfs_add_nondir(trans, dentry, inode, 1);

	err = btrfs_add_nondir(trans, dentry, inode, 1, index);



	if (err)

		drop_inode = 1;
@@ -2544,6 +2547,7 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 
	int err = 0;

	int drop_on_err = 0;

	u64 objectid = 0;

	u64 index = 0;

	unsigned long nr = 1;



	err = btrfs_check_free_space(root, 1, 0);
@@ -2567,7 +2571,8 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 
	inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,

				dentry->d_name.len,

				dentry->d_parent->d_inode->i_ino, objectid,

				BTRFS_I(dir)->block_group, S_IFDIR | mode);

				BTRFS_I(dir)->block_group, S_IFDIR | mode,

				&index);

	if (IS_ERR(inode)) {

		err = PTR_ERR(inode);

		goto out_fail;
@@ -2588,7 +2593,7 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 
	if (err)

		goto out_fail;



	err = btrfs_add_link(trans, dentry, inode, 0);

	err = btrfs_add_link(trans, dentry, inode, 0, index);

	if (err)

		goto out_fail;
@@ -3203,9 +3208,10 @@ int btrfs_create_subvol_root(struct btrfs_root *new_root, 
		struct btrfs_block_group_cache *block_group)

{

	struct inode *inode;

	u64 index = 0;



	inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,

				new_dirid, block_group, S_IFDIR | 0700);

				new_dirid, block_group, S_IFDIR | 0700, &index);

	if (IS_ERR(inode))

		return PTR_ERR(inode);

	inode->i_op = &btrfs_dir_inode_operations;
@@ -3384,6 +3390,7 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry, 
	struct inode *new_inode = new_dentry->d_inode;

	struct inode *old_inode = old_dentry->d_inode;

	struct timespec ctime = CURRENT_TIME;

	u64 index = 0;

	int ret;



	if (S_ISDIR(old_inode->i_mode) && new_inode &&
@@ -3419,11 +3426,11 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry, 
				goto out_fail;

		}

	}

	ret = btrfs_set_inode_index(new_dir, old_inode);

	ret = btrfs_set_inode_index(new_dir, old_inode, &index);

	if (ret)

		goto out_fail;



	ret = btrfs_add_link(trans, new_dentry, old_inode, 1);

	ret = btrfs_add_link(trans, new_dentry, old_inode, 1, index);

	if (ret)

		goto out_fail;
@@ -3464,6 +3471,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 
	int err;

	int drop_inode = 0;

	u64 objectid;

	u64 index = 0 ;

	int name_len;

	int datasize;

	unsigned long ptr;
@@ -3491,7 +3499,8 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 
	inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,

				dentry->d_name.len,

				dentry->d_parent->d_inode->i_ino, objectid,

				BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);

				BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO,

				&index);

	err = PTR_ERR(inode);

	if (IS_ERR(inode))

		goto out_unlock;
@@ -3503,7 +3512,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 
	}



	btrfs_set_trans_block_group(trans, inode);

	err = btrfs_add_nondir(trans, dentry, inode, 0);

	err = btrfs_add_nondir(trans, dentry, inode, 0, index);

	if (err)

		drop_inode = 1;

	else {