Make use of fms extensions and add a struct ovl_renamedata which embedds the vfs struct and adds overlayfs specific data. Signed-off-by: Christian Brauner --- fs/overlayfs/dir.c | 272 ++++++++++++++++++++++++++++------------------------- 1 file changed, 144 insertions(+), 128 deletions(-) diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index 86b72bf87833..cd2b397d23a0 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -1090,103 +1090,37 @@ static int ovl_set_redirect(struct dentry *dentry, bool samedir) return err; } -static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir, - struct dentry *old, struct inode *newdir, - struct dentry *new, unsigned int flags) +struct ovl_renamedata { + struct renamedata; + struct dentry *opaquedir; + struct dentry *olddentry; + struct dentry *newdentry; + bool cleanup_whiteout; +}; + +static int do_ovl_rename(struct ovl_renamedata *ovlrd, struct list_head *list) { - int err; - struct dentry *old_upperdir; - struct dentry *new_upperdir; - struct dentry *olddentry = NULL; - struct dentry *newdentry = NULL; - struct dentry *trap, *de; - bool old_opaque; - bool new_opaque; - bool cleanup_whiteout = false; - bool update_nlink = false; + struct dentry *old = ovlrd->old_dentry; + struct dentry *new = ovlrd->new_dentry; + struct ovl_fs *ofs = OVL_FS(old->d_sb); + unsigned int flags = ovlrd->flags; + struct dentry *old_upperdir = ovl_dentry_upper(ovlrd->old_parent); + struct dentry *new_upperdir = ovl_dentry_upper(ovlrd->new_parent); + bool samedir = ovlrd->old_parent == ovlrd->new_parent; bool overwrite = !(flags & RENAME_EXCHANGE); bool is_dir = d_is_dir(old); bool new_is_dir = d_is_dir(new); - bool samedir = olddir == newdir; - struct dentry *opaquedir = NULL; - const struct cred *old_cred = NULL; - struct ovl_fs *ofs = OVL_FS(old->d_sb); - LIST_HEAD(list); - - err = -EINVAL; - if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE)) - goto out; - - flags &= ~RENAME_NOREPLACE; - - /* Don't copy up directory trees */ - err = -EXDEV; - if (!ovl_can_move(old)) - goto out; - if (!overwrite && !ovl_can_move(new)) - goto out; - - if (overwrite && new_is_dir && !ovl_pure_upper(new)) { - err = ovl_check_empty_dir(new, &list); - if (err) - goto out; - } - - if (overwrite) { - if (ovl_lower_positive(old)) { - if (!ovl_dentry_is_whiteout(new)) { - /* Whiteout source */ - flags |= RENAME_WHITEOUT; - } else { - /* Switch whiteouts */ - flags |= RENAME_EXCHANGE; - } - } else if (is_dir && ovl_dentry_is_whiteout(new)) { - flags |= RENAME_EXCHANGE; - cleanup_whiteout = true; - } - } - - err = ovl_copy_up(old); - if (err) - goto out; - - err = ovl_copy_up(new->d_parent); - if (err) - goto out; - if (!overwrite) { - err = ovl_copy_up(new); - if (err) - goto out; - } else if (d_inode(new)) { - err = ovl_nlink_start(new); - if (err) - goto out; - - update_nlink = true; - } - - if (!update_nlink) { - /* ovl_nlink_start() took ovl_want_write() */ - err = ovl_want_write(old); - if (err) - goto out; - } - - old_cred = ovl_override_creds(old->d_sb); + struct dentry *trap, *de; + bool old_opaque, new_opaque; + int err; - if (!list_empty(&list)) { - opaquedir = ovl_clear_empty(new, &list); - err = PTR_ERR(opaquedir); - if (IS_ERR(opaquedir)) { - opaquedir = NULL; - goto out_revert_creds; - } + if (!list_empty(list)) { + de = ovl_clear_empty(new, list); + if (IS_ERR(de)) + return PTR_ERR(de); + ovlrd->opaquedir = de; } - old_upperdir = ovl_dentry_upper(old->d_parent); - new_upperdir = ovl_dentry_upper(new->d_parent); - if (!samedir) { /* * When moving a merge dir or non-dir with copy up origin into @@ -1195,32 +1129,30 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir, * lookup the origin inodes of the entries to fill d_ino. */ if (ovl_type_origin(old)) { - err = ovl_set_impure(new->d_parent, new_upperdir); + err = ovl_set_impure(ovlrd->new_parent, new_upperdir); if (err) - goto out_revert_creds; + return err; } if (!overwrite && ovl_type_origin(new)) { - err = ovl_set_impure(old->d_parent, old_upperdir); + err = ovl_set_impure(ovlrd->old_parent, old_upperdir); if (err) - goto out_revert_creds; + return err; } } trap = lock_rename(new_upperdir, old_upperdir); - if (IS_ERR(trap)) { - err = PTR_ERR(trap); - goto out_revert_creds; - } + if (IS_ERR(trap)) + return PTR_ERR(trap); de = ovl_lookup_upper(ofs, old->d_name.name, old_upperdir, old->d_name.len); err = PTR_ERR(de); if (IS_ERR(de)) goto out_unlock; - olddentry = de; + ovlrd->olddentry = de; err = -ESTALE; - if (!ovl_matches_upper(old, olddentry)) + if (!ovl_matches_upper(old, ovlrd->olddentry)) goto out_unlock; de = ovl_lookup_upper(ofs, new->d_name.name, new_upperdir, @@ -1228,23 +1160,23 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir, err = PTR_ERR(de); if (IS_ERR(de)) goto out_unlock; - newdentry = de; + ovlrd->newdentry = de; old_opaque = ovl_dentry_is_opaque(old); new_opaque = ovl_dentry_is_opaque(new); err = -ESTALE; if (d_inode(new) && ovl_dentry_upper(new)) { - if (opaquedir) { - if (newdentry != opaquedir) + if (ovlrd->opaquedir) { + if (ovlrd->newdentry != ovlrd->opaquedir) goto out_unlock; } else { - if (!ovl_matches_upper(new, newdentry)) + if (!ovl_matches_upper(new, ovlrd->newdentry)) goto out_unlock; } } else { - if (!d_is_negative(newdentry)) { - if (!new_opaque || !ovl_upper_is_whiteout(ofs, newdentry)) + if (!d_is_negative(ovlrd->newdentry)) { + if (!new_opaque || !ovl_upper_is_whiteout(ofs, ovlrd->newdentry)) goto out_unlock; } else { if (flags & RENAME_EXCHANGE) @@ -1252,38 +1184,39 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir, } } - if (olddentry == trap) + if (ovlrd->olddentry == trap) goto out_unlock; - if (newdentry == trap) + if (ovlrd->newdentry == trap) goto out_unlock; - if (olddentry->d_inode == newdentry->d_inode) + if (ovlrd->olddentry->d_inode == ovlrd->newdentry->d_inode) goto out_unlock; err = 0; if (ovl_type_merge_or_lower(old)) err = ovl_set_redirect(old, samedir); - else if (is_dir && !old_opaque && ovl_type_merge(new->d_parent)) - err = ovl_set_opaque_xerr(old, olddentry, -EXDEV); + else if (is_dir && !old_opaque && ovl_type_merge(ovlrd->new_parent)) + err = ovl_set_opaque_xerr(old, ovlrd->olddentry, -EXDEV); if (err) goto out_unlock; if (!overwrite && ovl_type_merge_or_lower(new)) err = ovl_set_redirect(new, samedir); else if (!overwrite && new_is_dir && !new_opaque && - ovl_type_merge(old->d_parent)) - err = ovl_set_opaque_xerr(new, newdentry, -EXDEV); + ovl_type_merge(ovlrd->old_parent)) + err = ovl_set_opaque_xerr(new, ovlrd->newdentry, -EXDEV); if (err) goto out_unlock; - err = ovl_do_rename(ofs, old_upperdir, olddentry, - new_upperdir, newdentry, flags); + err = ovl_do_rename(ofs, old_upperdir, ovlrd->olddentry, + new_upperdir, ovlrd->newdentry, flags); +out_unlock: unlock_rename(new_upperdir, old_upperdir); if (err) - goto out_revert_creds; + return err; - if (cleanup_whiteout) - ovl_cleanup(ofs, old_upperdir, newdentry); + if (ovlrd->cleanup_whiteout) + ovl_cleanup(ofs, old_upperdir, ovlrd->newdentry); if (overwrite && d_inode(new)) { if (new_is_dir) @@ -1292,9 +1225,9 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir, ovl_drop_nlink(new); } - ovl_dir_modified(old->d_parent, ovl_type_origin(old) || + ovl_dir_modified(ovlrd->old_parent, ovl_type_origin(old) || (!overwrite && ovl_type_origin(new))); - ovl_dir_modified(new->d_parent, ovl_type_origin(old) || + ovl_dir_modified(ovlrd->new_parent, ovl_type_origin(old) || (d_inode(new) && ovl_type_origin(new))); /* copy ctime: */ @@ -1302,22 +1235,105 @@ static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir, if (d_inode(new) && ovl_dentry_upper(new)) ovl_copyattr(d_inode(new)); -out_revert_creds: + return err; +} + +static int ovl_rename(struct mnt_idmap *idmap, struct inode *olddir, + struct dentry *old, struct inode *newdir, + struct dentry *new, unsigned int flags) +{ + int err; + bool update_nlink = false; + bool overwrite = !(flags & RENAME_EXCHANGE); + bool is_dir = d_is_dir(old); + bool new_is_dir = d_is_dir(new); + const struct cred *old_cred = NULL; + struct ovl_renamedata ovlrd = { + .old_parent = old->d_parent, + .old_dentry = old, + .new_parent = new->d_parent, + .new_dentry = new, + .flags = flags, + .cleanup_whiteout = false, + }; + LIST_HEAD(list); + + err = -EINVAL; + if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE)) + goto out; + + flags &= ~RENAME_NOREPLACE; + + /* Don't copy up directory trees */ + err = -EXDEV; + if (!ovl_can_move(old)) + goto out; + if (!overwrite && !ovl_can_move(new)) + goto out; + + if (overwrite && new_is_dir && !ovl_pure_upper(new)) { + err = ovl_check_empty_dir(new, &list); + if (err) + goto out; + } + + if (overwrite) { + if (ovl_lower_positive(old)) { + if (!ovl_dentry_is_whiteout(new)) { + /* Whiteout source */ + ovlrd.flags |= RENAME_WHITEOUT; + } else { + /* Switch whiteouts */ + ovlrd.flags |= RENAME_EXCHANGE; + } + } else if (is_dir && ovl_dentry_is_whiteout(new)) { + ovlrd.flags |= RENAME_EXCHANGE; + ovlrd.cleanup_whiteout = true; + } + } + + err = ovl_copy_up(old); + if (err) + goto out; + + err = ovl_copy_up(new->d_parent); + if (err) + goto out; + if (!overwrite) { + err = ovl_copy_up(new); + if (err) + goto out; + } else if (d_inode(new)) { + err = ovl_nlink_start(new); + if (err) + goto out; + + update_nlink = true; + } + + if (!update_nlink) { + /* ovl_nlink_start() took ovl_want_write() */ + err = ovl_want_write(old); + if (err) + goto out; + } + + old_cred = ovl_override_creds(old->d_sb); + + err = do_ovl_rename(&ovlrd, &list); + ovl_revert_creds(old_cred); if (update_nlink) ovl_nlink_end(new); else ovl_drop_write(old); + + dput(ovlrd.newdentry); + dput(ovlrd.olddentry); + dput(ovlrd.opaquedir); out: - dput(newdentry); - dput(olddentry); - dput(opaquedir); ovl_cache_free(&list); return err; - -out_unlock: - unlock_rename(new_upperdir, old_upperdir); - goto out_revert_creds; } static int ovl_create_tmpfile(struct file *file, struct dentry *dentry, -- 2.47.3