Unverified Commit c826229c authored by Jeff Layton's avatar Jeff Layton Committed by Christian Brauner
Browse files

vfs: make vfs_create break delegations on parent directory 



In order to add directory delegation support, we need to break
delegations on the parent whenever there is going to be a change in the
directory.

Add a delegated_inode parameter to vfs_create. Most callers are
converted to pass in NULL, but do_mknodat() is changed to wait for a
delegation break if there is one.

Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarNeilBrown <neil@brown.name>
Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20251111-dir-deleg-ro-v6-10-52f3feebb2f2@kernel.org


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 85bbffca

fs/ecryptfs/inode.c

+1 −1
Original line number Diff line number Diff line
@@ -188,7 +188,7 @@ ecryptfs_do_create(struct inode *directory_inode, 


	rc = lock_parent(ecryptfs_dentry, &lower_dentry, &lower_dir);

	if (!rc)

		rc = vfs_create(&nop_mnt_idmap, lower_dentry, mode);

		rc = vfs_create(&nop_mnt_idmap, lower_dentry, mode, NULL);

	if (rc) {

		printk(KERN_ERR "%s: Failure to create dentry in lower fs; "

		       "rc = [%d]\n", __func__, rc);

fs/namei.c

+13 −2
Original line number Diff line number Diff line
@@ -3463,6 +3463,7 @@ static inline umode_t vfs_prepare_mode(struct mnt_idmap *idmap, 
 * @idmap:	idmap of the mount the inode was found from

 * @dentry:	dentry of the child file

 * @mode:	mode of the child file

 * @di:		returns parent inode, if the inode is delegated.

 *

 * Create a new file.

 *
@@ -3472,7 +3473,8 @@ static inline umode_t vfs_prepare_mode(struct mnt_idmap *idmap, 
 * On non-idmapped mounts or if permission checking is to be performed on the

 * raw inode simply pass @nop_mnt_idmap.

 */

int vfs_create(struct mnt_idmap *idmap, struct dentry *dentry, umode_t mode)

int vfs_create(struct mnt_idmap *idmap, struct dentry *dentry, umode_t mode,

	       struct delegated_inode *di)

{

	struct inode *dir = d_inode(dentry->d_parent);

	int error;
@@ -3486,6 +3488,9 @@ int vfs_create(struct mnt_idmap *idmap, struct dentry *dentry, umode_t mode) 


	mode = vfs_prepare_mode(idmap, dir, mode, S_IALLUGO, S_IFREG);

	error = security_inode_create(dir, dentry, mode);

	if (error)

		return error;

	error = try_break_deleg(dir, di);

	if (error)

		return error;

	error = dir->i_op->create(idmap, dir, dentry, mode, true);
@@ -4358,6 +4363,7 @@ static int may_mknod(umode_t mode) 
static int do_mknodat(int dfd, struct filename *name, umode_t mode,

		unsigned int dev)

{

	struct delegated_inode di = { };

	struct mnt_idmap *idmap;

	struct dentry *dentry;

	struct path path;
@@ -4381,7 +4387,7 @@ static int do_mknodat(int dfd, struct filename *name, umode_t mode, 
	idmap = mnt_idmap(path.mnt);

	switch (mode & S_IFMT) {

		case 0: case S_IFREG:

			error = vfs_create(idmap, dentry, mode);

			error = vfs_create(idmap, dentry, mode, &di);

			if (!error)

				security_path_post_mknod(idmap, dentry);

			break;
@@ -4396,6 +4402,11 @@ static int do_mknodat(int dfd, struct filename *name, umode_t mode, 
	}

out2:

	end_creating_path(&path, dentry);

	if (is_delegated(&di)) {

		error = break_deleg_wait(&di);

		if (!error)

			goto retry;

	}

	if (retry_estale(error, lookup_flags)) {

		lookup_flags |= LOOKUP_REVAL;

		goto retry;

fs/nfsd/nfs3proc.c

+1 −1
Original line number Diff line number Diff line
@@ -344,7 +344,7 @@ nfsd3_create_file(struct svc_rqst *rqstp, struct svc_fh *fhp, 
	status = fh_fill_pre_attrs(fhp);

	if (status != nfs_ok)

		goto out;

	host_err = vfs_create(&nop_mnt_idmap, child, iap->ia_mode);

	host_err = vfs_create(&nop_mnt_idmap, child, iap->ia_mode, NULL);

	if (host_err < 0) {

		status = nfserrno(host_err);

		goto out;

fs/nfsd/vfs.c

+1 −1
Original line number Diff line number Diff line
@@ -1552,7 +1552,7 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp, 
	err = 0;

	switch (type) {

	case S_IFREG:

		host_err = vfs_create(&nop_mnt_idmap, dchild, iap->ia_mode);

		host_err = vfs_create(&nop_mnt_idmap, dchild, iap->ia_mode, NULL);

		if (!host_err)

			nfsd_check_ignore_resizing(iap);

		break;

fs/open.c

+1 −1
Original line number Diff line number Diff line
@@ -1171,7 +1171,7 @@ struct file *dentry_create(const struct path *path, int flags, umode_t mode, 
	if (IS_ERR(f))

		return f;



	error = vfs_create(mnt_idmap(path->mnt), path->dentry, mode);

	error = vfs_create(mnt_idmap(path->mnt), path->dentry, mode, NULL);

	if (!error)

		error = vfs_open(path, f);