+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL4(
+ int, readlinkat, int, dirfd, const char*, pathname, char*, buf, size_t, size)
+{
+ int errno;
+ struct v_fd* fd_s;
+ if ((errno = vfs_getfd(dirfd, &fd_s))) {
+ goto done;
+ }
+
+ pathname = pathname ? pathname : "";
+
+ struct v_dnode* dnode;
+ if (!(errno = vfs_walk(
+ fd_s->file->dnode, pathname, &dnode, NULL, VFS_WALK_NOFOLLOW))) {
+ errno = vfs_readlink(fd_s->file->dnode, buf, size);
+ }
+
+ if (errno >= 0) {
+ return errno;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+/*
+ NOTE
+ When we perform operation that could affect the layout of
+ directory (i.e., rename, mkdir, rmdir). We must lock the parent dir
+ whenever possible. This will blocking any ongoing path walking to reach
+ it hence avoid any partial state.
+*/
+
+__DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk_proc(pathname, &dnode, NULL, 0))) {
+ return DO_STATUS(errno);
+ }
+
+ lock_dnode(dnode);
+
+ if ((errno = vfs_check_writable(dnode))) {
+ goto done;
+ }
+
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+
+ if (dnode->ref_count > 1 || dnode->inode->open_count) {
+ errno = EBUSY;
+ goto done;
+ }
+
+ if (!llist_empty(&dnode->children)) {
+ errno = ENOTEMPTY;
+ goto done;
+ }
+
+ struct v_dnode* parent = dnode->parent;
+
+ if (!parent) {
+ errno = EINVAL;
+ goto done;
+ }
+
+ lock_dnode(parent);
+ lock_inode(parent->inode);
+
+ if (!(dnode->inode->itype & F_MFILE)) {
+ errno = parent->inode->ops->rmdir(parent->inode, dnode);
+ if (!errno) {
+ vfs_dcache_remove(dnode);
+ }
+ } else {
+ errno = ENOTDIR;
+ }
+
+ unlock_inode(parent->inode);
+ unlock_dnode(parent);
+
+done:
+ unlock_dnode(dnode);
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, mkdir, const char*, path)
+{
+ int errno = 0;
+ struct v_dnode *parent, *dir;
+ char name_value[VFS_NAME_MAXLEN];
+ struct hstr name = HHSTR(name_value, 0, 0);
+
+ if ((errno = vfs_walk_proc(path, &parent, &name, VFS_WALK_PARENT))) {
+ goto done;
+ }
+
+ if (!(errno = vfs_walk(parent, name_value, &dir, NULL, 0))) {
+ errno = EEXIST;
+ goto done;
+ }
+
+ if ((errno = vfs_check_writable(parent))) {
+ goto done;
+ }
+
+ if (!(dir = vfs_d_alloc(parent, &name))) {
+ errno = ENOMEM;
+ goto done;
+ }
+
+ lock_dnode(parent);
+ lock_inode(parent->inode);
+
+ if ((parent->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = ENOTSUP;
+ } else if (!parent->inode->ops->mkdir) {
+ errno = ENOTSUP;
+ } else if ((parent->inode->itype & F_FILE)) {
+ errno = ENOTDIR;
+ } else if (!(errno = parent->inode->ops->mkdir(parent->inode, dir))) {
+ vfs_dcache_add(parent, dir);
+ goto cleanup;
+ }
+
+ vfs_d_free(dir);
+
+cleanup:
+ unlock_inode(parent->inode);
+ unlock_dnode(parent);
+done:
+ return DO_STATUS(errno);
+}
+
+int
+__vfs_do_unlink(struct v_dnode* dnode)
+{
+ int errno;
+ struct v_inode* inode = dnode->inode;
+
+ if (dnode->ref_count > 1) {
+ return EBUSY;
+ }
+
+ if ((errno = vfs_check_writable(dnode))) {
+ return errno;
+ }
+
+ lock_inode(inode);
+
+ if (inode->open_count) {
+ errno = EBUSY;
+ } else if ((inode->itype & F_MFILE)) {
+ errno = inode->ops->unlink(inode);
+ if (!errno) {
+ vfs_d_free(dnode);
+ }
+ } else {
+ errno = EISDIR;
+ }
+
+ unlock_inode(inode);
+
+ return errno;
+}
+
+__DEFINE_LXSYSCALL1(int, unlink, const char*, pathname)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk_proc(pathname, &dnode, NULL, 0))) {
+ goto done;
+ }
+
+ errno = __vfs_do_unlink(dnode);
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(int, unlinkat, int, fd, const char*, pathname)
+{
+ int errno;
+ struct v_fd* fd_s;
+ if ((errno = vfs_getfd(fd, &fd_s))) {
+ goto done;
+ }
+
+ struct v_dnode* dnode;
+ if (!(errno = vfs_walk(fd_s->file->dnode, pathname, &dnode, NULL, 0))) {
+ errno = __vfs_do_unlink(dnode);
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(int, link, const char*, oldpath, const char*, newpath)
+{
+ int errno;
+ struct v_dnode *dentry, *to_link, *name_dentry, *name_file;
+
+ errno = __vfs_try_locate_file(oldpath, &dentry, &to_link, 0);
+ if (!errno) {
+ errno = __vfs_try_locate_file(
+ newpath, &name_dentry, &name_file, FLOCATE_CREATE_ONLY);
+ if (!errno) {
+ errno = vfs_link(to_link, name_file);
+ }
+ }
+ return DO_STATUS(errno);