1 /* 2 * linux/fs/ufs/namei.c 3 * 4 * Migration to usage of "page cache" on May 2006 by 5 * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base. 6 * 7 * Copyright (C) 1998 8 * Daniel Pirkl <daniel.pirkl@email.cz> 9 * Charles University, Faculty of Mathematics and Physics 10 * 11 * from 12 * 13 * linux/fs/ext2/namei.c 14 * 15 * Copyright (C) 1992, 1993, 1994, 1995 16 * Remy Card (card@masi.ibp.fr) 17 * Laboratoire MASI - Institut Blaise Pascal 18 * Universite Pierre et Marie Curie (Paris VI) 19 * 20 * from 21 * 22 * linux/fs/minix/namei.c 23 * 24 * Copyright (C) 1991, 1992 Linus Torvalds 25 * 26 * Big-endian to little-endian byte-swapping/bitmaps by 27 * David S. Miller (davem@caip.rutgers.edu), 1995 28 */ 29 30 #include <linux/time.h> 31 #include <linux/fs.h> 32 33 #include "ufs_fs.h" 34 #include "ufs.h" 35 #include "util.h" 36 37 static inline int ufs_add_nondir(struct dentry *dentry, struct inode *inode) 38 { 39 int err = ufs_add_link(dentry, inode); 40 if (!err) { 41 d_instantiate(dentry, inode); 42 return 0; 43 } 44 inode_dec_link_count(inode); 45 iput(inode); 46 return err; 47 } 48 49 static struct dentry *ufs_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) 50 { 51 struct inode * inode = NULL; 52 ino_t ino; 53 54 if (dentry->d_name.len > UFS_MAXNAMLEN) 55 return ERR_PTR(-ENAMETOOLONG); 56 57 lock_ufs(dir->i_sb); 58 ino = ufs_inode_by_name(dir, &dentry->d_name); 59 if (ino) 60 inode = ufs_iget(dir->i_sb, ino); 61 unlock_ufs(dir->i_sb); 62 return d_splice_alias(inode, dentry); 63 } 64 65 /* 66 * By the time this is called, we already have created 67 * the directory cache entry for the new file, but it 68 * is so far negative - it has no inode. 69 * 70 * If the create succeeds, we fill in the inode information 71 * with d_instantiate(). 72 */ 73 static int ufs_create (struct inode * dir, struct dentry * dentry, umode_t mode, 74 struct nameidata *nd) 75 { 76 struct inode *inode; 77 int err; 78 79 UFSD("BEGIN\n"); 80 81 inode = ufs_new_inode(dir, mode); 82 err = PTR_ERR(inode); 83 84 if (!IS_ERR(inode)) { 85 inode->i_op = &ufs_file_inode_operations; 86 inode->i_fop = &ufs_file_operations; 87 inode->i_mapping->a_ops = &ufs_aops; 88 mark_inode_dirty(inode); 89 lock_ufs(dir->i_sb); 90 err = ufs_add_nondir(dentry, inode); 91 unlock_ufs(dir->i_sb); 92 } 93 UFSD("END: err=%d\n", err); 94 return err; 95 } 96 97 static int ufs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev) 98 { 99 struct inode *inode; 100 int err; 101 102 if (!old_valid_dev(rdev)) 103 return -EINVAL; 104 105 inode = ufs_new_inode(dir, mode); 106 err = PTR_ERR(inode); 107 if (!IS_ERR(inode)) { 108 init_special_inode(inode, mode, rdev); 109 ufs_set_inode_dev(inode->i_sb, UFS_I(inode), rdev); 110 mark_inode_dirty(inode); 111 lock_ufs(dir->i_sb); 112 err = ufs_add_nondir(dentry, inode); 113 unlock_ufs(dir->i_sb); 114 } 115 return err; 116 } 117 118 static int ufs_symlink (struct inode * dir, struct dentry * dentry, 119 const char * symname) 120 { 121 struct super_block * sb = dir->i_sb; 122 int err = -ENAMETOOLONG; 123 unsigned l = strlen(symname)+1; 124 struct inode * inode; 125 126 if (l > sb->s_blocksize) 127 goto out_notlocked; 128 129 lock_ufs(dir->i_sb); 130 inode = ufs_new_inode(dir, S_IFLNK | S_IRWXUGO); 131 err = PTR_ERR(inode); 132 if (IS_ERR(inode)) 133 goto out; 134 135 if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) { 136 /* slow symlink */ 137 inode->i_op = &ufs_symlink_inode_operations; 138 inode->i_mapping->a_ops = &ufs_aops; 139 err = page_symlink(inode, symname, l); 140 if (err) 141 goto out_fail; 142 } else { 143 /* fast symlink */ 144 inode->i_op = &ufs_fast_symlink_inode_operations; 145 memcpy(UFS_I(inode)->i_u1.i_symlink, symname, l); 146 inode->i_size = l-1; 147 } 148 mark_inode_dirty(inode); 149 150 err = ufs_add_nondir(dentry, inode); 151 out: 152 unlock_ufs(dir->i_sb); 153 out_notlocked: 154 return err; 155 156 out_fail: 157 inode_dec_link_count(inode); 158 iput(inode); 159 goto out; 160 } 161 162 static int ufs_link (struct dentry * old_dentry, struct inode * dir, 163 struct dentry *dentry) 164 { 165 struct inode *inode = old_dentry->d_inode; 166 int error; 167 168 lock_ufs(dir->i_sb); 169 170 inode->i_ctime = CURRENT_TIME_SEC; 171 inode_inc_link_count(inode); 172 ihold(inode); 173 174 error = ufs_add_nondir(dentry, inode); 175 unlock_ufs(dir->i_sb); 176 return error; 177 } 178 179 static int ufs_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode) 180 { 181 struct inode * inode; 182 int err; 183 184 lock_ufs(dir->i_sb); 185 inode_inc_link_count(dir); 186 187 inode = ufs_new_inode(dir, S_IFDIR|mode); 188 err = PTR_ERR(inode); 189 if (IS_ERR(inode)) 190 goto out_dir; 191 192 inode->i_op = &ufs_dir_inode_operations; 193 inode->i_fop = &ufs_dir_operations; 194 inode->i_mapping->a_ops = &ufs_aops; 195 196 inode_inc_link_count(inode); 197 198 err = ufs_make_empty(inode, dir); 199 if (err) 200 goto out_fail; 201 202 err = ufs_add_link(dentry, inode); 203 if (err) 204 goto out_fail; 205 unlock_ufs(dir->i_sb); 206 207 d_instantiate(dentry, inode); 208 out: 209 return err; 210 211 out_fail: 212 inode_dec_link_count(inode); 213 inode_dec_link_count(inode); 214 iput (inode); 215 out_dir: 216 inode_dec_link_count(dir); 217 unlock_ufs(dir->i_sb); 218 goto out; 219 } 220 221 static int ufs_unlink(struct inode *dir, struct dentry *dentry) 222 { 223 struct inode * inode = dentry->d_inode; 224 struct ufs_dir_entry *de; 225 struct page *page; 226 int err = -ENOENT; 227 228 de = ufs_find_entry(dir, &dentry->d_name, &page); 229 if (!de) 230 goto out; 231 232 err = ufs_delete_entry(dir, de, page); 233 if (err) 234 goto out; 235 236 inode->i_ctime = dir->i_ctime; 237 inode_dec_link_count(inode); 238 err = 0; 239 out: 240 return err; 241 } 242 243 static int ufs_rmdir (struct inode * dir, struct dentry *dentry) 244 { 245 struct inode * inode = dentry->d_inode; 246 int err= -ENOTEMPTY; 247 248 lock_ufs(dir->i_sb); 249 if (ufs_empty_dir (inode)) { 250 err = ufs_unlink(dir, dentry); 251 if (!err) { 252 inode->i_size = 0; 253 inode_dec_link_count(inode); 254 inode_dec_link_count(dir); 255 } 256 } 257 unlock_ufs(dir->i_sb); 258 return err; 259 } 260 261 static int ufs_rename(struct inode *old_dir, struct dentry *old_dentry, 262 struct inode *new_dir, struct dentry *new_dentry) 263 { 264 struct inode *old_inode = old_dentry->d_inode; 265 struct inode *new_inode = new_dentry->d_inode; 266 struct page *dir_page = NULL; 267 struct ufs_dir_entry * dir_de = NULL; 268 struct page *old_page; 269 struct ufs_dir_entry *old_de; 270 int err = -ENOENT; 271 272 old_de = ufs_find_entry(old_dir, &old_dentry->d_name, &old_page); 273 if (!old_de) 274 goto out; 275 276 if (S_ISDIR(old_inode->i_mode)) { 277 err = -EIO; 278 dir_de = ufs_dotdot(old_inode, &dir_page); 279 if (!dir_de) 280 goto out_old; 281 } 282 283 if (new_inode) { 284 struct page *new_page; 285 struct ufs_dir_entry *new_de; 286 287 err = -ENOTEMPTY; 288 if (dir_de && !ufs_empty_dir(new_inode)) 289 goto out_dir; 290 291 err = -ENOENT; 292 new_de = ufs_find_entry(new_dir, &new_dentry->d_name, &new_page); 293 if (!new_de) 294 goto out_dir; 295 ufs_set_link(new_dir, new_de, new_page, old_inode); 296 new_inode->i_ctime = CURRENT_TIME_SEC; 297 if (dir_de) 298 drop_nlink(new_inode); 299 inode_dec_link_count(new_inode); 300 } else { 301 err = ufs_add_link(new_dentry, old_inode); 302 if (err) 303 goto out_dir; 304 if (dir_de) 305 inode_inc_link_count(new_dir); 306 } 307 308 /* 309 * Like most other Unix systems, set the ctime for inodes on a 310 * rename. 311 */ 312 old_inode->i_ctime = CURRENT_TIME_SEC; 313 314 ufs_delete_entry(old_dir, old_de, old_page); 315 mark_inode_dirty(old_inode); 316 317 if (dir_de) { 318 ufs_set_link(old_inode, dir_de, dir_page, new_dir); 319 inode_dec_link_count(old_dir); 320 } 321 return 0; 322 323 324 out_dir: 325 if (dir_de) { 326 kunmap(dir_page); 327 page_cache_release(dir_page); 328 } 329 out_old: 330 kunmap(old_page); 331 page_cache_release(old_page); 332 out: 333 return err; 334 } 335 336 const struct inode_operations ufs_dir_inode_operations = { 337 .create = ufs_create, 338 .lookup = ufs_lookup, 339 .link = ufs_link, 340 .unlink = ufs_unlink, 341 .symlink = ufs_symlink, 342 .mkdir = ufs_mkdir, 343 .rmdir = ufs_rmdir, 344 .mknod = ufs_mknod, 345 .rename = ufs_rename, 346 }; 347