| /* |
| * linux/fs/minix/namei.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| */ |
| |
| #include "minix.h" |
| |
| static int add_nondir(struct dentry *dentry, struct inode *inode) |
| { |
| int err = minix_add_link(dentry, inode); |
| if (!err) { |
| d_instantiate(dentry, inode); |
| return 0; |
| } |
| inode_dec_link_count(inode); |
| iput(inode); |
| return err; |
| } |
| |
| static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) |
| { |
| struct inode * inode = NULL; |
| ino_t ino; |
| |
| if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen) |
| return ERR_PTR(-ENAMETOOLONG); |
| |
| ino = minix_inode_by_name(dentry); |
| if (ino) { |
| inode = minix_iget(dir->i_sb, ino); |
| if (IS_ERR(inode)) |
| return ERR_CAST(inode); |
| } |
| d_add(dentry, inode); |
| return NULL; |
| } |
| |
| static int minix_mknod(struct inode * dir, struct dentry *dentry, int mode, dev_t rdev) |
| { |
| int error; |
| struct inode *inode; |
| |
| if (!old_valid_dev(rdev)) |
| return -EINVAL; |
| |
| inode = minix_new_inode(dir, mode, &error); |
| |
| if (inode) { |
| minix_set_inode(inode, rdev); |
| mark_inode_dirty(inode); |
| error = add_nondir(dentry, inode); |
| } |
| return error; |
| } |
| |
| static int minix_create(struct inode * dir, struct dentry *dentry, int mode, |
| struct nameidata *nd) |
| { |
| return minix_mknod(dir, dentry, mode, 0); |
| } |
| |
| static int minix_symlink(struct inode * dir, struct dentry *dentry, |
| const char * symname) |
| { |
| int err = -ENAMETOOLONG; |
| int i = strlen(symname)+1; |
| struct inode * inode; |
| |
| if (i > dir->i_sb->s_blocksize) |
| goto out; |
| |
| inode = minix_new_inode(dir, S_IFLNK | 0777, &err); |
| if (!inode) |
| goto out; |
| |
| minix_set_inode(inode, 0); |
| err = page_symlink(inode, symname, i); |
| if (err) |
| goto out_fail; |
| |
| err = add_nondir(dentry, inode); |
| out: |
| return err; |
| |
| out_fail: |
| inode_dec_link_count(inode); |
| iput(inode); |
| goto out; |
| } |
| |
| static int minix_link(struct dentry * old_dentry, struct inode * dir, |
| struct dentry *dentry) |
| { |
| struct inode *inode = old_dentry->d_inode; |
| |
| if (inode->i_nlink >= minix_sb(inode->i_sb)->s_link_max) |
| return -EMLINK; |
| |
| inode->i_ctime = CURRENT_TIME_SEC; |
| inode_inc_link_count(inode); |
| ihold(inode); |
| return add_nondir(dentry, inode); |
| } |
| |
| static int minix_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode) |
| { |
| struct inode * inode; |
| int err = -EMLINK; |
| |
| if (dir->i_nlink >= minix_sb(dir->i_sb)->s_link_max) |
| goto out; |
| |
| inode_inc_link_count(dir); |
| |
| inode = minix_new_inode(dir, S_IFDIR | mode, &err); |
| if (!inode) |
| goto out_dir; |
| |
| minix_set_inode(inode, 0); |
| |
| inode_inc_link_count(inode); |
| |
| err = minix_make_empty(inode, dir); |
| if (err) |
| goto out_fail; |
| |
| err = minix_add_link(dentry, inode); |
| if (err) |
| goto out_fail; |
| |
| d_instantiate(dentry, inode); |
| out: |
| return err; |
| |
| out_fail: |
| inode_dec_link_count(inode); |
| inode_dec_link_count(inode); |
| iput(inode); |
| out_dir: |
| inode_dec_link_count(dir); |
| goto out; |
| } |
| |
| static int minix_unlink(struct inode * dir, struct dentry *dentry) |
| { |
| int err = -ENOENT; |
| struct inode * inode = dentry->d_inode; |
| struct page * page; |
| struct minix_dir_entry * de; |
| |
| de = minix_find_entry(dentry, &page); |
| if (!de) |
| goto end_unlink; |
| |
| err = minix_delete_entry(de, page); |
| if (err) |
| goto end_unlink; |
| |
| inode->i_ctime = dir->i_ctime; |
| inode_dec_link_count(inode); |
| end_unlink: |
| return err; |
| } |
| |
| static int minix_rmdir(struct inode * dir, struct dentry *dentry) |
| { |
| struct inode * inode = dentry->d_inode; |
| int err = -ENOTEMPTY; |
| |
| if (minix_empty_dir(inode)) { |
| err = minix_unlink(dir, dentry); |
| if (!err) { |
| inode_dec_link_count(dir); |
| inode_dec_link_count(inode); |
| } |
| } |
| return err; |
| } |
| |
| static int minix_rename(struct inode * old_dir, struct dentry *old_dentry, |
| struct inode * new_dir, struct dentry *new_dentry) |
| { |
| struct minix_sb_info * info = minix_sb(old_dir->i_sb); |
| struct inode * old_inode = old_dentry->d_inode; |
| struct inode * new_inode = new_dentry->d_inode; |
| struct page * dir_page = NULL; |
| struct minix_dir_entry * dir_de = NULL; |
| struct page * old_page; |
| struct minix_dir_entry * old_de; |
| int err = -ENOENT; |
| |
| old_de = minix_find_entry(old_dentry, &old_page); |
| if (!old_de) |
| goto out; |
| |
| if (S_ISDIR(old_inode->i_mode)) { |
| err = -EIO; |
| dir_de = minix_dotdot(old_inode, &dir_page); |
| if (!dir_de) |
| goto out_old; |
| } |
| |
| if (new_inode) { |
| struct page * new_page; |
| struct minix_dir_entry * new_de; |
| |
| err = -ENOTEMPTY; |
| if (dir_de && !minix_empty_dir(new_inode)) |
| goto out_dir; |
| |
| err = -ENOENT; |
| new_de = minix_find_entry(new_dentry, &new_page); |
| if (!new_de) |
| goto out_dir; |
| minix_set_link(new_de, new_page, old_inode); |
| new_inode->i_ctime = CURRENT_TIME_SEC; |
| if (dir_de) |
| drop_nlink(new_inode); |
| inode_dec_link_count(new_inode); |
| } else { |
| if (dir_de) { |
| err = -EMLINK; |
| if (new_dir->i_nlink >= info->s_link_max) |
| goto out_dir; |
| } |
| err = minix_add_link(new_dentry, old_inode); |
| if (err) |
| goto out_dir; |
| if (dir_de) |
| inode_inc_link_count(new_dir); |
| } |
| |
| minix_delete_entry(old_de, old_page); |
| mark_inode_dirty(old_inode); |
| |
| if (dir_de) { |
| minix_set_link(dir_de, dir_page, new_dir); |
| inode_dec_link_count(old_dir); |
| } |
| return 0; |
| |
| out_dir: |
| if (dir_de) { |
| kunmap(dir_page); |
| page_cache_release(dir_page); |
| } |
| out_old: |
| kunmap(old_page); |
| page_cache_release(old_page); |
| out: |
| return err; |
| } |
| |
| /* |
| * directories can handle most operations... |
| */ |
| const struct inode_operations minix_dir_inode_operations = { |
| .create = minix_create, |
| .lookup = minix_lookup, |
| .link = minix_link, |
| .unlink = minix_unlink, |
| .symlink = minix_symlink, |
| .mkdir = minix_mkdir, |
| .rmdir = minix_rmdir, |
| .mknod = minix_mknod, |
| .rename = minix_rename, |
| .getattr = minix_getattr, |
| }; |