1 // SPDX-License-Identifier: GPL-2.0
3 * linux/fs/sysv/namei.c
6 * Copyright (C) 1991, 1992 Linus Torvalds
9 * Copyright (C) 1993 Pascal Haible, Bruno Haible
12 * Copyright (C) 1993 Bruno Haible
13 * Copyright (C) 1997, 1998 Krzysztof G. Baranowski
16 #include <linux/pagemap.h>
19 static int add_nondir(struct dentry *dentry, struct inode *inode)
21 int err = sysv_add_link(dentry, inode);
23 d_instantiate(dentry, inode);
26 inode_dec_link_count(inode);
31 static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry, unsigned int flags)
33 struct inode * inode = NULL;
36 if (dentry->d_name.len > SYSV_NAMELEN)
37 return ERR_PTR(-ENAMETOOLONG);
38 ino = sysv_inode_by_name(dentry);
40 inode = sysv_iget(dir->i_sb, ino);
41 return d_splice_alias(inode, dentry);
44 static int sysv_mknod(struct inode * dir, struct dentry * dentry, umode_t mode, dev_t rdev)
49 if (!old_valid_dev(rdev))
52 inode = sysv_new_inode(dir, mode);
56 sysv_set_inode(inode, rdev);
57 mark_inode_dirty(inode);
58 err = add_nondir(dentry, inode);
63 static int sysv_create(struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
65 return sysv_mknod(dir, dentry, mode, 0);
68 static int sysv_symlink(struct inode * dir, struct dentry * dentry,
71 int err = -ENAMETOOLONG;
72 int l = strlen(symname)+1;
75 if (l > dir->i_sb->s_blocksize)
78 inode = sysv_new_inode(dir, S_IFLNK|0777);
83 sysv_set_inode(inode, 0);
84 err = page_symlink(inode, symname, l);
88 mark_inode_dirty(inode);
89 err = add_nondir(dentry, inode);
94 inode_dec_link_count(inode);
99 static int sysv_link(struct dentry * old_dentry, struct inode * dir,
100 struct dentry * dentry)
102 struct inode *inode = d_inode(old_dentry);
104 inode->i_ctime = current_time(inode);
105 inode_inc_link_count(inode);
108 return add_nondir(dentry, inode);
111 static int sysv_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
113 struct inode * inode;
116 inode_inc_link_count(dir);
118 inode = sysv_new_inode(dir, S_IFDIR|mode);
119 err = PTR_ERR(inode);
123 sysv_set_inode(inode, 0);
125 inode_inc_link_count(inode);
127 err = sysv_make_empty(inode, dir);
131 err = sysv_add_link(dentry, inode);
135 d_instantiate(dentry, inode);
140 inode_dec_link_count(inode);
141 inode_dec_link_count(inode);
144 inode_dec_link_count(dir);
148 static int sysv_unlink(struct inode * dir, struct dentry * dentry)
150 struct inode * inode = d_inode(dentry);
152 struct sysv_dir_entry * de;
155 de = sysv_find_entry(dentry, &page);
159 err = sysv_delete_entry (de, page);
163 inode->i_ctime = dir->i_ctime;
164 inode_dec_link_count(inode);
169 static int sysv_rmdir(struct inode * dir, struct dentry * dentry)
171 struct inode *inode = d_inode(dentry);
172 int err = -ENOTEMPTY;
174 if (sysv_empty_dir(inode)) {
175 err = sysv_unlink(dir, dentry);
178 inode_dec_link_count(inode);
179 inode_dec_link_count(dir);
186 * Anybody can rename anything with this: the permission checks are left to the
187 * higher-level routines.
189 static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
190 struct inode * new_dir, struct dentry * new_dentry,
193 struct inode * old_inode = d_inode(old_dentry);
194 struct inode * new_inode = d_inode(new_dentry);
195 struct page * dir_page = NULL;
196 struct sysv_dir_entry * dir_de = NULL;
197 struct page * old_page;
198 struct sysv_dir_entry * old_de;
201 if (flags & ~RENAME_NOREPLACE)
204 old_de = sysv_find_entry(old_dentry, &old_page);
208 if (S_ISDIR(old_inode->i_mode)) {
210 dir_de = sysv_dotdot(old_inode, &dir_page);
216 struct page * new_page;
217 struct sysv_dir_entry * new_de;
220 if (dir_de && !sysv_empty_dir(new_inode))
224 new_de = sysv_find_entry(new_dentry, &new_page);
227 sysv_set_link(new_de, new_page, old_inode);
228 new_inode->i_ctime = current_time(new_inode);
230 drop_nlink(new_inode);
231 inode_dec_link_count(new_inode);
233 err = sysv_add_link(new_dentry, old_inode);
237 inode_inc_link_count(new_dir);
240 sysv_delete_entry(old_de, old_page);
241 mark_inode_dirty(old_inode);
244 sysv_set_link(dir_de, dir_page, new_dir);
245 inode_dec_link_count(old_dir);
262 * directories can handle most operations...
264 const struct inode_operations sysv_dir_inode_operations = {
265 .create = sysv_create,
266 .lookup = sysv_lookup,
268 .unlink = sysv_unlink,
269 .symlink = sysv_symlink,
273 .rename = sysv_rename,
274 .getattr = sysv_getattr,