[PATCH v6 10/17] vfs: make vfs_create break delegations on parent directory
From: Jeff Layton <jlayton@kernel.org>
Date: 2025-11-11 14:13:38
Also in:
linux-api, linux-cifs, linux-fsdevel, linux-nfs, linux-unionfs, linux-xfs, lkml, netfs
Subsystem:
ecrypt file system, filesystems (vfs and infrastructure), kernel nfsd, sunrpc, and lockd servers, kernel smb3 server (ksmbd), overlay filesystem, the rest · Maintainers:
Tyler Hicks, Alexander Viro, Christian Brauner, Chuck Lever, Jeff Layton, Namjae Jeon, Steve French, Miklos Szeredi, Amir Goldstein, Linus Torvalds
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: Jan Kara <jack@suse.cz> Reviewed-by: NeilBrown <neil@brown.name> Signed-off-by: Jeff Layton <jlayton@kernel.org> --- fs/ecryptfs/inode.c | 2 +- fs/namei.c | 15 +++++++++++++-- fs/nfsd/nfs3proc.c | 2 +- fs/nfsd/vfs.c | 2 +- fs/open.c | 2 +- fs/overlayfs/overlayfs.h | 2 +- fs/smb/server/vfs.c | 2 +- include/linux/fs.h | 3 ++- 8 files changed, 21 insertions(+), 9 deletions(-)
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index d109e3763a88150bfe64cd2d5564dc9802ef3386..3341f00dd08753c8feab184dd82b8bfa63d3724a 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c@@ -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);
diff --git a/fs/namei.c b/fs/namei.c
index 9586c6aba6eae05a9fc3c103b8501d98767bef53..b20f053374a578d36fb764e0df80fb7db9230dbe 100644
--- a/fs/namei.c
+++ b/fs/namei.c@@ -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;
diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c
index 30ea7ffa2affdb9a959b0fd15a630de056d6dc3c..2cb972b5ed994d69995146aeeac8651c1c04fa46 100644
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c@@ -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;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 464fd54675f3b16fce9ae5f05ad22e0e6b363eb3..de5f46f8c6d3ab24fabddeed9bd59adbe7a486df 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c@@ -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;
diff --git a/fs/open.c b/fs/open.c
index e440f58e3ce81e137aabdf00510d839342a19219..92cf2e11781b0efd16fe0b751286ce943ea6b4e2 100644
--- a/fs/open.c
+++ b/fs/open.c@@ -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);
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 2bdc434941ebc70f6d4f57cca4f68125112a7bc4..e30441cc9c63ff8b6c055db80be7974501d0023b 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h@@ -235,7 +235,7 @@ static inline int ovl_do_create(struct ovl_fs *ofs, struct inode *dir, struct dentry *dentry, umode_t mode) { - int err = vfs_create(ovl_upper_mnt_idmap(ofs), dentry, mode); + int err = vfs_create(ovl_upper_mnt_idmap(ofs), dentry, mode, NULL); pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err); return err;
diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c
index 83ece2de4b23bf9209137e7ca414a72439b5cc2e..3747851b61c8bad4c00e49866c380c32e9f53a4b 100644
--- a/fs/smb/server/vfs.c
+++ b/fs/smb/server/vfs.c@@ -188,7 +188,7 @@ int ksmbd_vfs_create(struct ksmbd_work *work, const char *name, umode_t mode) } mode |= S_IFREG; - err = vfs_create(mnt_idmap(path.mnt), dentry, mode); + err = vfs_create(mnt_idmap(path.mnt), dentry, mode, NULL); if (!err) { ksmbd_vfs_inherit_owner(work, d_inode(path.dentry), d_inode(dentry));
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 21876ef1fec90181b9878372c7c7e710773aae9f..83b05aec4e10c846d3168018fb62284e45ceb1a8 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h@@ -2111,7 +2111,8 @@ bool inode_owner_or_capable(struct mnt_idmap *idmap, /* * VFS helper functions.. */ -int vfs_create(struct mnt_idmap *, struct dentry *, umode_t); +int vfs_create(struct mnt_idmap *, struct dentry *, umode_t, + struct delegated_inode *); struct dentry *vfs_mkdir(struct mnt_idmap *, struct inode *, struct dentry *, umode_t, struct delegated_inode *); int vfs_mknod(struct mnt_idmap *, struct inode *, struct dentry *,
--
2.51.1